In situ measurement of free radical formation during the thermal decomposition of grape seed oil using “spin trapping” and electron paramagnetic resonance spectroscopy

The generation of free radical intermediates as a result of the oxidative degradation of lipid molecules during the heating of grape seed oil has been established by a combination of “spin trapping” and electron paramagnetic resonance spectroscopy. The effects of temperature on the rates of formation and decomposition of the adduct with the spin trapN-t-butyl-α-phenylnitrone (PBN) have been investigated over the temperature range 105–180°C. The results show that PBN can be used for studies of free radical processes in oils in situ in the spectrometer cavity at temperatures up to 180°C.     

Elements that Influence the Implementation of Crisis Preparedness Measures by Meeting Planners

The purpose of this study was to analyse the adoption of crisis preparedness measures by meeting planners. The study sought to determine how the adoption of crisis preparedness measures relates to meeting planner characteristics and identify the elements that influence their adoption (or lack of adoption) of these measures. A survey of professional meeting planners identified significant differences in the frequency of use of some key core crisis preparedness measures. Additionally, 10 categories of elements influencing the adoption of or failure to adopt crisis preparedness measures were identified. The findings of this study should be of interest to meeting organizers and professionals who want to make their meetings more crisis prepared rather than crisis prone.     

Membrane processing of used frying oils

Studies were conducted with used frying oils in a flat membrane batch cell using five different types of polymeric membranes to decrease the soluble degradation products. During membrane processing, triglycerides permeated preferentially compared to the majority of the polar compounds including oxidation products, polymers, and color compounds. Two of the composite membranes, NTGS-AX and NTGS-2200, selectively rejected polar compounds and oxidation products to the extent of 25–48% and 24–44% respectively. The reduction in Lovibond color values (5R+Y) was in the range of 83–93%. The viscosity of the used frying oil was reduced to the extent of 22%. The composite membranes were effective in reducing the soluble impurities, as well as insoluble particulates, without causing any undesirable changes to the oil. The membrane process appears to improve the life of used frying oils and does not have the disadvantages associated with the active filtration systems, however, for commercial application the permeate flux needs to be improved considerably.     

Simulation of slip band evolution in duplex Ti–6Al–4V

Formation of slip bands plays an important role in deformation and fatigue processes of duplex Ti–6Al–4V. In this study, shear-enhanced crystal plasticity constitutive relations are proposed to account for the slip softening due to breakdown of the short-range order between titanium and aluminum atoms. A hybrid strategy is developed which allows the softening to occur in slip bands only within the primary α phase, with the degree of localization depending on the specific polycrystalline initial-boundary-value problem and the requirements for compatibility of each grain or phase with its neighbors. The proposed model is calibrated by performing finite-element (FE) simulations on an experimentally studied Ti–6Al–4V alloy. The slip behavior of a Ti–6Al–4V sample subjected to an in situ (scanning electron microscopy (SEM)) tensile test is investigated. A two-dimensional (2-D) FE with 3-D crystal plasticity relations is constructed to represent the microstructure of the Ti–6Al–4V sample. Due to the lack of access to fully 3-D microstructure, a generalized plane-strain condition is used in the FE model which assumes columnar grains that are free of net traction in the direction normal to the surface. The assumption of columnar grains significantly reduces the computational cost. The contours of effective plastic strain are compared with the surface SEM micrographs from experiments at various strain levels. It is shown that the proposed approach for modeling slip bands qualitatively captures experimentally observed slip band behavior.     

NMR SPECTROSCOPY IN THE CHARACTERIZATION OF EIGHT SELECTED ASPHALTS

ABSTRACT

Nuclear Magnetic Resonance (NMR) spectroscopy has been used to partially characterize eight selected asphalts. This report describes the initial efforts in this endeavor. Proton and carbon spectra have been collected and analyzed for percent aromatic content as well as aromatic substitution. DEFT results, chemical shifts and literature precedent have been used to assign the major resonances in the aliphatic region to chemical entities. Finally, using elemental analysis data, molecular weight data and NMR results, average structures for the eight asphalts have been derived     

Ultraviolet Protection Properties of Metal Salts Treated Cotton Fabrics

The aim of this study was to study the influence of metal salt treatment on UV protection property of cotton fabrics. CuCl₂, SbCl₃, TiO₂, Co₃O₄, SnO₂, Ni(NO₃)₂和AgNO₃ were used as metallic salts. Mentioned metallic salts were treated on cotton fabric, and the Ultraviolet Protection Factors (UPF) was examined. The morphology of fibers loaded with different metal salts was assessed by SEM. The treated cotton fabrics were then characterized by X-ray diffraction (XRD) and the crystallinity and crystals size for all samples were studied. Metal salt loaded fabrics showed better UV protection properties compared to untreated cotton fabrics. The results confirmed that metal salts have potential applications for producing ultra violet protective cotton fabric.     

Sustainable sludge management in developing countries.

Worldwide, unsanitary conditions are responsible for more than three million deaths annually. One of the reasons is the low level of sanitation in developing countries. Particularly, sludge from these regions has a high parasite concentration and low heavy metal content even though the available information is limited. Different issues needed to achieve a sustainable sludge management in developing nations are analysed. Based on this analysis some conclusions arise: sludge management plays an important role in sanitation programs by helping reduce health problems and associated risks; investments in sanitation should consider sludge management within the overall projects; the main restriction for reusing sludge is the high microbial concentration, which requires a science-based decision on the treatment process, while heavy metals are generally low; adequate sludge management needs the commitment of those sectors involved in the development and enforcement of the regulations as well as those that are directly related to its generation, treatment, reuse or disposal; current regulations have followed different approaches, based mainly on local conditions, but they favour sludge reuse to fight problems like soil degradation, reduced crop production, and the increased use of inorganic fertilizers. This paper summarises an overview of these issues.     

Food insecurity in canadian adults receiving diabetes care

Purpose: The prevalence of adult-level household food insecurity was examined among clients receiving outpatient diabetes health care services. Methods: Participants were adults diagnosed with diabetes mellitus, who attended individual counselling sessions at Calgary's main clinic from January to April 2010. Clinicians were trained to administer the Household Food Security Survey Module (HFSSM), and did so with clients' assent during their scheduled sessions. Results: The prevalence of adult-level household food insecurity among 314 respondents was 15.0% (95% confidence interval [CI], 11.2 to 19.4); 6.7% (95% CI, 4.2 to 10.0) of clinic attendees were categorized as severely food insecure. The comparable rates obtained in Alberta in 2007 using the same instrument (HFSSM) were 5.6% and 1.2%, respectively. Conclusions: Household food insecurity rates among individuals with diabetes in active care are higher than rates reported in Canadian population surveys. Severe food insecurity, indicating reduced food intake and disrupted eating patterns, may affect this population's ability to follow a pattern of healthy eating necessary for effective diabetes management. This study reinforces the importance of assessing clients' inability to access food because of financial constraints, and indicates that screening with a validated measure may facilitate identification of clients at risk.     

Finite Point Low Mach Number Algorithm for Unsteady Nonisothermal Flows Application to the Study of Reactive Flow Past a Thin Catalytic Wire

A numerical algorithm is presented for the solution of low Mach number unsteady nonisothermal flows at moderate Reynolds numbers (Re ～ 100) with variable transport properties. The low Mach number limit is approached by using a relaxation method of the pseudo-compressibility type that has proved to be numerically robust and accurate enough to be used in industrial applications. Time integration is explicit and space integration is based on a finite point approach. Solver validation includes a sensitivity analysis and a comparison with previously published results concerning the flow around heated cylinders at different Re and temperature loadings. Then, the solver is applied to calculate the flow of a reacting mixture past a thin catalytic wire, a problem of interest for power MEMS design (micro catalytic reactors), aiming to determine the chemical-to-thermal energy conversion rate at the catalytic wire.