Numerical investigation of the oxy-fuel combustion in large scale boilers adopting the ECO-Scrub technology

The present paper presents a three-dimensional numerical investigation of a pulverized-fuel, tangentially-fired utility boiler located at Florina/Greece under air, partial and full oxy-fuel conditions. Heat and mass transfer and major species concentration, such as CO₂, CO and O₂ are calculated; whilst the results for the reference air case scenario studied are in good agreement with the corresponding operational data measured in the plant, both for combustion calculations and NO_x emissions. Results for the partial and full oxy-fuel operation scenarios are in line with similar experimental and numerical investigations found in the recent literature. This numerical investigation of oxy-fuel conditions scenarios prior to their implementation under real scale conditions demonstrates the utmost of its importance, since significant results regarding the operation of a boiler in terms of lignite particle trajectories and burning rates are attained. Furthermore, NO_x calculations have been performed for all the examined case studies.     

Surface-Related States in Oxidized Silicon Nanocrystals Enhance Carrier Relaxation and Inhibit Auger Recombination

We have studied ultrafast carrier dynamics in oxidized silicon nanocrystals (NCs) and the role that surface-related states play in the various relaxation mechanisms over a broad range of photon excitation energy corresponding to energy levels below and above the direct bandgap of the formed NCs. Transient photoinduced absorption techniques have been employed to investigate the effects of surface-related states on the relaxation dynamics of photogenerated carriers in 2.8 nm oxidized silicon NCs. Independent of the excitation photon energy, non-degenerate measurements reveal several distinct relaxation regions corresponding to relaxation of photoexcited carriers from the initial excited states, the lowest indirect states and the surface-related states. Furthermore, degenerate and non-degenerate measurements at difference excitation fluences reveal a linear dependence of the maximum of the photoinduced absorption (PA) signal and an identical decay, suggesting that Auger recombination does not play a significant role in these nanostructures even for fluence generating up to 20 carriers/NC.     

Spatially resolved electronic and vibronic properties of single diamondoid molecules

Diamondoids are a unique form of carbon nanostructure best described as hydrogen-terminated diamond molecules. Their diamond-cage structures and tetrahedral sp3 hybrid bonding create new possibilities for tuning electronic bandgaps, optical properties, thermal transport and mechanical strength at the nanoscale. The recently discovered higher diamondoids have thus generated much excitement in regards to their potential versatility as nanoscale devices. Despite this excitement, however, very little is known about the properties of isolated diamondoids on metal surfaces, a very relevant system for molecular electronics. For example, it is unclear how the microscopic characteristics of molecular orbitals and local electron-vibrational coupling affect electron conduction, emission and energy transfer in the diamondoids. Here, we report the first single-molecule study of tetramantane diamondoids on Au(111) using scanning tunnelling microscopy and spectroscopy. We find that the diamondoid electronic structure and electron-vibrational coupling exhibit unique and unexpected spatial correlations characterized by pronounced nodal structure across the molecular surfaces. Ab initio pseudopotential density functional calculations reveal that much of the observed electronic and vibronic properties of diamondoids are determined by surface hydrogen terminations, a feature having important implications for designing future diamondoid-based molecular devices.     

ACBD3 Bioinformatic Analysis and Protein Expression in Breast Cancer Cells

ACBD3 overexpression has previously been found to correlate with worse prognosis for breast cancer patients and, as an incredibly diverse protein in both function and cellular localisation, ACBD3 may have a larger role in breast cancer than previously thought. This study further investigated ACBD3′s role in breast cancer. Bioinformatic databases were queried to characterise ACBD3 expression and mutation in breast cancer and to investigate how overexpression affects breast cancer patient outcomes. Immunohistochemistry was carried out to examine ACBD3 location within cells and tissue structures. ACBD3 was more highly expressed in breast cancer than in any other cancer or matched normal tissue, and expression over the median level resulted in reduced relapse-free, overall, and distant metastasis-free survival for breast cancer patients as a whole, with some differences observed between subtypes. IHC analysis found that ACBD3 levels varied based on hormone receptor status, indicating that ACBD3 could be a candidate biomarker for poor patient prognosis in breast cancer and may possibly be a biomarker for ER signal reprogramming of precancerous breast tissue.     

Molecular structure and charge distribution in organometallics of the 4f and 5f elements V: crystal and molecular structure of tetrakis(ν-cyclopentadienyl)-thorium(IV) and the temperature dependence of its electrical dipole moment

The crystal and molecular structure of Th(C₅H₅)₄, was investigated by single crystal X-ray diffraction. The compound crystallizes tetragonal with a = 868.3(1), C = 1064.4(3) pm with two molecules per unit cell. The average Th—Cp distance of 260.6 pm is in good agreement with the predicted distance of 258.8 pm, and is larger than the corresponding distance of the uranium compound (253.8 pm). The temperature dependence of the dipole moment of the title compound, of thorium tetramethylcyclopentadienide (Cp′,Th), and of the homologous uranium compound in benzene solution is discussed with respect to their molecular structure.     

Comparison of the antimicrobial and antioxidant activities of selected wheat varieties

Antibacterial and antioxidant activities of wheat seed ethyl acetate extracts for Jokyoung (JK), Dark northern spring (DNS), Keumkang (KK), Woori (WR), and Winter wheat (WW) were investigated. Antibacterial activities were evaluated in vitro against the common food and cosmetic industry contaminants Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus using well diffusion assays. WW had the highest inhibitory activity against all tested strains, with S. aureus being the most sensitive strain. The minimum inhibitory concentration (MIC) values of WW and WR against S. aureus were 0.50 and 1.25 mg/mL, respectively. The 2,6-dimethoxy-1,4- benzoquinone (DMBQ) content was measured using HPLC. The antibacterial activities of wheat seed extracts were correlated with the total phenolic contents (Pearson’s correlation coefficient=0.994), with the ABTS radical scavenging activity (0.978), and with the DMBQ content (0.968). WW and WR have potential for use as natural antimicrobials for prevention of food and cosmetics spoilage.     

Design structure matrix (DSM) method application to issue of modeling and analyzing the fault tree of a wind energy asset

The perpetual energy production of a wind farm could be accomplished (under proper weather conditions) if no failures occurred. But even the best possible design, manufacturing, and maintenance of a system cannot eliminate the failure possibility. In order to understand and minimize the system failures, the most crucial components of the wind turbines, which are prone to failures, should be identified. Moreover, it is essential to determine and classify the criticality of the system failures according to the impact of these failure events on wind turbine safety. The present study is processing the failure data from a wind farm and uses the Fault Tree Analysis as a baseline for applying the Design Structure Matrix technique to reveal the failure and risk interactions between wind turbine subsystems. Based on the analysis performed and by introducing new importance measures, the “readiness to fail” of a subsystem in conjunction with the “failure riskiness” can determine the “failure criticality.” The value of the failure criticality can define the frame within which interventions could be done. The arising interventions could be applied either to the whole system or could be focused in specified pairs of wind turbine subsystems. In conclusion, the method analyzed in the present research can be effectively applied by the wind turbine manufacturers and the wind farm operators as an operation framework, which can lead to a limited (as possible) design‐out maintenance cost, failures' minimization, and safety maximization for the whole wind turbine system.     

Inhibition of Staphylococcus aureus by Phenolic Phytochemicals of Selected Clonal Herbs Species of Lamiaceae Family and Likely Mode of Action through Proline Oxidation

Staphylococcus aureus, a Gram-positive organism, is responsible for numerous infections ranging in severity from skin and soft tissue infections to endocarditis and septic arthritis. Further, Staphylococcal food poisoning (SFP) caused by enterotoxigenic staphylococci is one of the main food-borne diseases. In this study, several single-seed origin clonal lines of herbs from Lamiaceae family were screened for antimicrobial applications against S. aureus. These clonal lines have consistent total phenolic content, phenolic profile and antioxidant activity as opposed to heterogenous phenolic profiles of typical herbal extracts. The clonal extracts of specific herb species were evaluated for anti- S. aureus activity. Water extracts of clonal lemon balm had the highest anti- S. aureus activity followed by clonal extracts of rosemary RoLA, sage, oregano, rosemary Ro-6, rosemary RoK-2 and chocolate mint. The anti- S. aureus activity of the water extracts correlated with gallic acid and caffeic acid content, which in pure form showed high anti- S. aureus activity. Based on the rationale that gallic acid and caffeic acid were likely proline analogs affecting proline oxidation, the countering effect of proline to overcome their anti- S. aureus activity was evaluated. Results indicated proline can overcome the inhibitory effects of gallic acid and caffeic acid. These results point to the likely role of phenolic oxidation via proline dehydrogenase, which could be an important target for inhibition by phenolic phytochemicals behaving as proline analog mimics. This mode of regulation by phenolics at the bacterial proline dehydrogenase in the plasma membrane may be an important antimicrobial defense in plants and has consequences for disruption of critical energy metabolism of invading bacterial pathogen. This rationale could be used to design new antimicrobial strategies against S. aureus and other relevant bacterial pathogens.     

Exploring barriers and opportunities in adopting crowdsourcing based new product development in manufacturing SMEs

Crowdsourcing is an innovative business practice of obtaining needed services, ideas, or content or even funds by soliciting contributions from a large group of people(the ‘Crowd'). The potential benefits of utilizing crowdsourcing in product design are well-documented, but little research exists on what are the barriers and opportunities in adopting crowdsourcing in new product development(NPD) of manufacturing SMEs. In order to answer the above questions, a Proof of Market study is carried out on crowdsourcing-based product design under an Innovate UK funded Smart project, which aims at identifying the needs, challenges and future development opportunities associated with adopting crowdsourcing strategies for NPD. The research findings from this study are reported here and can be used to guide future development of crowdsourcing-based collaborative design methods and tools and provide some practical references for industry to adopt this new and emerging collaborative design method in their business.