A new classification approach for prediction of flyrock throw in surface mines

Bulletin of Engineering Geology and the Environment - A novel classification approach was proposed for prediction of flyrock throw distance based on the site measurements performed in a sandstone...     

Thermoelastic transition kinetics of a gamma irradiated CuZnAl shape memory alloy

Many types of shape memory alloys have been used in nuclear reactors and aerospace applications where they are exposed to high levels of various kinds of radiation. The effect of gamma irradiation on the transformation kinetics of thermoelastic transformations in a shape memory CuZnAl alloy was investigated by differential scanning calorimetry (DSC) with heating/cooling rates of 10, 20, 30 and 40 °C/min. Irradiation doses of 10, 20, 30 and 40 kGy were applied to the samples of the alloy. Changes in Gibbs free energies, entropies and elastic energies were calculated. Reverse transition temperatures A _s and A _f systematically decreased with increasing doses, although forward transition temperatures M _s and M _f underwent a minimum value at a dose of 20 kGy. Hysteresis in the transition temperatures changed as an inverse parabolic function of the irradiation dose. The activation energies of transformations were calculated by using Kissinger and Osawa methods.     

The influence of binder content on the water transport properties of waterborne acrylic paints

Diffusion coefficients and sorption isotherms of water in waterborne acrylic paint films and in the pure binder of the paints have been measured by gravimetric sorption. Solubility of water was found to enhance with the increased binder content in the paint films while the diffusivity of water decreased significantly. Sorption isotherms in the paint and pure copolymer films were correlated with the Flory Huggins theory and ENSIC model, respectively. Fickian diffusion was observed in both types of films and the kinetic data were best correlated with a numerical model which takes into account the concentration dependency of the diffusion coefficient and the dimensional change of the film due to sorption. It was concluded that the utilization of a simplified analytical solution may lead to significant errors in the estimation of diffusivities.     

Determination of Coal Rank by Fuzzy Logic: A Case Study of Coal from Central Anatolia,Turkey

Koyunagili coalfield in the Beypazari basin of the Central Anatolia was investigated and coal ranks were determined using fuzzy Mamdani model based on ASTM coal rank classification. This is a pilot study to investigate the applicability of the fuzzy model to determine the ranking of any coal seam. The Koyunagili coalfield, which is located at the southern part of the Beypazari basin, consists of the late Miocene coal seam within the tuffaceous rocks. The mineable coal seam is split by a 0.5–0.55 m thick clayey limestone into the upper (1.2–1.3 m thick) and lower (0.4 m thick) benches. A total of 28 profile coal samples from underground mines were collected. The samples have an average of 30.9% moisture (as-received), 23% ash yield, and 2.9% total sulphur and 4167 kcal/kg gross calorific value on an air-dried basis. Mean random reflectance values of huminite have an average of 0.34%, and show no differences across the coalfield. Coal ranking has been determined by the fuzzy Mamdani model. During processing, fixed carbon content (FCC), volatile matter values (VMV), calorific value (CV), and vitrinite/huminite reflectance (Ro %) parameters are inputs, and a total of 10 rules are used for the model. Modeling results are consistent with the previous studies.     

Influence of fat content and emulsifier type on the rheological properties of cake batter

The effects of fat content and emulsifier type on the rheological properties of cake batter have been investigated by using a parallel-plate rheometer. The apparent viscosity of cake batter with five different fat concentrations (0, 12.5, 25, 37.5, and 50%) and two types of emulsifier, namely Purawave and Lecigran, was studied as a function of the shear rate. In addition, the time dependency of different cake formulations was investigated. It was found that cake batter with different fat concentrations and emulsifier types exhibited shear thinning and time-independent behavior. Experimental data provided a good fit for the power law model. The increase in fat content and addition of emulsifier caused a decrease in the apparent viscosity. The flow behavior index was not found to be dependent on the composition of cake batter.     

Removal of copper(II) and cadmium(II) ions from aqueous solutions by biosorption onto pine cone

In this study, the removal of copper(II) and cadmium(II) ions from aqueous solutions by biosorption onto pine cone was studied. Variables that affect the biosorption process such as pH, biosorbent dosage, initial metal ion concentration, contact time and temperature of solution were optimized. Experimental data were fitted to Langmuir, Freundlich, Dubinin Radushkevich and Temkin isotherm models to investigate the equilibrium isotherms. Pseudo-first-order, pseudo-second-order and intraparticle diffusion kinetic models were used to determine the biosorption mechanism. The thermodynamics of biosorption were studied for predicting the nature of biosorption. Experimental results showed that pine cone could be evaluated as an alternative precursor for removal of heavy metal ions from aqueous solutions, due to its high biosorption capacity, availability, and low cost.     

Halogen lamp–microwave combination baking of cookies

The effects of halogen lamp–microwave combination baking on the quality of cookies in terms of texture, color and spread ratio were studied. In addition, gelatinization and pasting properties of cookies baked in different ovens were assessed by using a Rapid Visco Analyzer. The hardness values of the cookies increased with increasing baking time and/or halogen power. The microwave power also contributed to cookie hardness. The lightness values of the cookies decreased, while the a* and E values increased linearly during baking at different halogen lamp and microwave powers. The spread ratio of conventionally baked cookies was significantly lower than that of the other cookies. Halogen lamp power, microwave power and baking time were found to have a significant effect on the spread ratio of the cookies. The moisture contents of the cookies decreased during baking as the halogen lamp and/or the microwave power level increased. The best baking condition in a halogen lamp–microwave combination oven to produce cookies having similar quality parameters as conventionally baked ones was baking at 70% halogen lamp and 20% microwave power levels for 5.5 min. The baking time of these cookies is half of that required in conventional baking.     

Gluten contamination in manufactured gluten-free foods in Turkey

ABSTRACT

Gluten contamination in manufactured gluten-free foods (mGFFs) is a major health, well-being and economic issue worldwide for both mandatory and voluntary GFF-consumers. Although scarce, a number of surveys have shown that up to 21.5 % of mGFFs in circulation in the market are contaminated with gluten. However, at the present time there is no published work reporting gluten contamination in mGFFs produced in Turkey. In this paper miscellaneous mGFFs produced in Turkey were analysed for gluten concentration (G) to fill this knowledge gap, and to compare the situation in Turkey with worldwide efforts on this issue. A total of 200 mGFFs from 8 product categories (snack, pasta, bread, cookie, cracker, farina, traditional and others), and manufactured using 7 main ingredients (cereal mixture, buckwheat, corn, rice, locust bean, potato, and others) were analysed. A significant portion of mGFFs (17.5 %) were contaminated with gluten and therefore unacceptable as being GFF. The results point to buckwheat as the main cause of this contamination. If buckwheat is excluded, the ratio of unacceptable mGFFs dramatically decreases to 6.3 % and probably to 1.8 %, which are comparable figures to those reported for other countries. Almost all countries are subjected to the same regulations on GFFs, and the problem of gluten contamination could readily be solved to a great extent if pre-market measures are mandated. Enforcing mGFF-producers to screen their raw materials and final products to detect the presence of gluten, and preventing the release of contaminated mGFFs into the market would be a practical measure in favour of all stakeholders involved in GFF-consumption.     

Effectiveness of chitosan‐based coating in improving shelf‐life of eggs

Despite eggs having a natural packaging—shell—they are perishable and can lose their quality during storage. Chitosan‐based coatings were applied to shell eggs to examine potential effects on egg quality properties (weight loss, Haugh unit, yolk index) during 4 weeks of storage. Mineral amounts in yolks were also evaluated after 4 weeks of storage. Three chitosan‐based coatings produced with organic acids (acetic‐(C‐AA), lactic‐(C‐LA), and propionic (C‐PA)) were evaluated on shelf‐life enhancements of fresh egg quality. All chitosan‐coated eggs showed greater interior quality than the non‐coated eggs. The coatings significantly maintained weight loss compared to the control specimen (4.96%). Lower weight loss (3.45% for C‐PA, 3.53% for C‐LA) was observed in the coated eggs. Eggshell chitosan coat containing lactic and propionic acids maintained higher Haugh unit and yolk index than eggs coated with acetic acid. Uncoated (UC) eggs changed from grade ‘A’ to ‘B’ after 1 week of storage. Chitosan‐based coating containing lactic and propionic acids maintained eggs in grade ‘A’ for 4 weeks. Haugh unit showed that C‐LA and C‐PA effectively maintained eggs at grade ‘A’ quality for at least 3 weeks more than control and 1 week more than C‐AA. Results also indicated that the chitosan coating maintained mineral amounts at nutritional values (especially calcium, iron and magnesium concentration) in yolks after 4 weeks storage. Copyright © 2006 Society of Chemical Industry