Microwave hybrid fast sintering of red clay ceramics

This work aimed to examine the performance of the hybrid sintering of clay ceramic in a microwave furnace, compared to the sintering process in a conventional furnace. The raw materials were subjected to X-ray fluorescence, loss on ignition (LOI), X-ray diffraction, particle size distribution, real specific mass, and thermogravimetric analyses. The red clay ceramic mass was prepared, extruded, pre-sintered in a conventional furnace at 600°C/60 min, and sintered at temperatures between 700 °C and 1100 °C. The sintering conventional (resistive oven) was carried out for 60 min with a heating rate of 10°C/min. In the microwave furnace, the sintering times were 5, 10, and 15 min, with a heating rate of 50°C/min, with a sintering chamber coated with silicon carbide (susceptor). The sintered specimens were characterized according to linear shrinkage, water absorption, apparent porosity, apparent specific mass, X-ray diffraction, Raman spectroscopy analysis, spectroscopy analysis in the ultraviolet and visible regions, microhardness, and scanning electron microscopy. The results showed that microwave sintering promoted an increase in the microhardness and apparent specific mass, and reduction in water absorption and apparent porosity values, due to greater densification in the microstructure. The best results occurred for specimens sintered at 1100°C.     

Development and characterization of dehydrated peanut–cowpea milk powder for use as a dairy milk substitute in chocolate manufacture

This study explored the feasibility of producing peanut–cowpea milk for use in vegetable milk chocolates. Development of the vegetable milk followed a 3 × 2 factorial design, with peanut–cowpea ratio (1:1, 1:2 and 1:3), and treatment with enzyme (i.e. enzyme hydrolyzed and non-hydrolyzed milk) as the factors. The milk was dehydrated and then milled using a hammer mill (mesh size 40). It was then used in recipes to produce chocolates and evaluated sensorially based on ranking for preference. Skimmed milk powder was used to produce the control chocolate. The ratio of cowpea to peanut affected the chemical and functional characteristics of the vegetable milk. Vegetable milk made from 1:2 ratios of peanuts:cowpea produced the most preferred chocolates. The successful application of this by industry will improve the utilization of the legume crops and enhance their market value.     

The common occurrence of furan fatty acids in plants

The observation that F-acids (1) occur in rat chow initiated a search for F-acids in human diet. We observed that the amount of F-acids with a pentyl side chain in α-position taken up with a one-day diet correlates well with the amount of excreted degradation products, the pentyl urofuran acids (2), (3) and (4). Therefore it can be concluded that F-acids with a pentyl side chain are not produced in the human body but are introduced through the diet. The origin of F-acids carrying an α-propyl side chain is less clear. The amount of propyl-urofuran acids (2) and (3) excreted in urine was found in one case out of three to be five times higher than the amount of F-acids carrying a propyl group in α-position taken up by the diet. Therefore, it can presently not be excluded that a portion of the propyl F-acids is produced by the body. F-acids found in human food are mainly introduced into the body by vegetables and fruits. F-acids were found also in birch leaves in considerable amounts, as well as in grasses, dandelion and clover leaves. Thus, we can conclude that F-acids are common constituents of plants.     

Psychometric qualities of the German version of the Posttraumatic Diagnostic Scale (PTDS).

In the present study, the psychometric properties of the German version of the Posttraumatic Diagnostic Scale (PTDS; A. Ehlers, R. Steil, H. Winter, & E. B. Foa, 1996) were evaluated in a sample of 143 trauma survivors. To investigate convergent and discriminant validity of this questionnaire, the authors assessed posttraumatic stress disorder (PTSD), anxiety, depression symptoms, and social phobia. Internal consistencies of the PTDS and its subscales as well as their association with related measures show that the German PTDS is a reliable and valid instrument for the assessment of posttraumatic stress symptoms. A 3-factor structure was found that is, however, not exactly in concordance with the Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; American Psychiatric Association, 2000) formulation (Reexperiencing, Avoidance, and Hyperarousal) but rather comprises a Reexperiencing/Avoidance factor; an Emotional Numbing/Hyperarousal factor; and a 3rd factor, consisting of Hypervigilance and an Exaggerated Startle Response. The findings are discussed with respect to their equivalency to the original PTDS, core symptoms of PTSD, and desirable future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychometric properties of the Posttraumatic Cognitions Inventory (PTCI) in a German sample of individuals with a history of trauma.

In this study, we examined the psychometric properties of the 33-item Posttraumatic Cognitions Inventory (Foa, Ehlers, Clark, Tolin, & Orsillo, 1999) in 213 individuals with accident-related trauma and 190 individuals with interpersonal trauma. Confirmatory factor analyses generally supported the scale's original three-factor structure—Negative Cognitions About Self (SELF), Negative Cognitions About World (WORLD), and Self-Blame (BLAME)—after four redundant items were excluded. However, in line with previous findings, results for BLAME remained inconclusive because the scale performed poorly with the individuals with accident-related trauma, whereas its fit with those with interpersonal trauma was acceptable. BLAME might possibly relate to trauma type. Our results indicate that the proposed 29-item version shows acceptable psychometric properties and that the role of BLAME should be further investigated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A new method for quantitative determination of BHA

A qualitative test developed by Laszlo has been adapted to the quantitative determination of BHA. The determination is based on measurement of the specific and sensitive color resulting from reaction of BHA with diazotized sulfanilic acid in alkaline solution. The red-purple color, which is stable for long periods, has an absorption maximum at 535 mμ. Beer’s law is obeyed, and a concentration range of 0.0001% to 0.01% BHA may be measured. The method requires careful adjustment of antioxidant-reagent ratios for rapid and maximum color development, The optimum ratios, the effect of alcohol, and interfering substances are diseussed. The method, as described, also provides for an accurate specific determination of BHA in fats and oils even when other antioxidants are present. Journal Pager No. 184, American Meat Institute Foundation. Presented at 50th Anniversary Meeting, American Oil Chemists’ Society, April 20–22, 1959, New Orleans, La. Chemist in the Division for Inspection of Animal Products (D.I.P.O.A.) of the Ministry of Agriculture (Rio de Janeiro, Brazil) and American Association of University Women Fellow at the American Meat Institute Foundation during 1958–59.     

NiAl2O4 catalysts prepared by combustion reaction using glycine as fuel

The aim of this work is to evaluate the influence of glycine fuel used in a stoichiometric proportion and with a 10% and 20% excess of this fuel in the preparation of NiAl₂O₄ catalyst by combustion reaction. The powders were characterized by XRD, textural analysis by the BET nitrogen adsorption method, particle size distribution, and FTIR. The results show the presence of NiAl₂O₄ as a major phase and traces of NiO and Ni in all the catalysts studied here. The crystallite sizes were 22 nm in the stoichiometric composition and 18 and 9 nm, respectively, in the composition containing 10% and 20% excess glycine. The powder obtained from all the compositions presented morphological characteristics with irregular plate-shaped agglomerates. The increase in excess glycine caused the particle size in the three compositions to decrease to 59, 54 and 38 nm and the agglomerate size to increase to 7, 8 and 12 μm, respectively.