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The aim of the present study was to analyze differences in the emotional processing (valence, arousal, and dominance) of food-related information in patients with eating disorders (ED), patients with obesity, and healthy women. Moreover, the mediator role of negative affect and the moderating role of the diagnostic group (ED vs. non-ED) were analyzed. Method: The sample consisted of 94 women (39 with eating disorders, 19 with obesity, and 36 healthy participants). Measures: International Affective Picture System (IAPS) food picture exposure task; Self-Assessment Manikin Analog-Visual Scale (SAM) appraising Arousal, Valence, and Dominance; Eating Attitudes Test (EAT-26); Positive and Negative Affect Schedule (PANAS). Results: Patients with purging symptomatology rated food images as more unpleasant than healthy women. Patients with purging and restrictive eating symptomatology showed higher levels of arousal and less dominance over the emotions experienced, compared to patients with obesity and healthy women. The mediation analysis showed that negative affect mediated the relationship between eating symptomatology (EAT-26) and the Valence of food images, as well as the control over the emotions experienced when viewing food images (Dominance). For the moderation analysis participants were regrouped into two groups (ED patients vs. non-ED patients). The direct relationship between eating symptomatology and food image valence was moderated by the diagnostic group. However, the group did not moderate the direct relationship between the EAT-26 and dominance over experienced emotions, or the indirect effect on eating symptomatology through negative affect. These results show the relevance of negative affect in the emotional processing of food-related information, and they support an eating disorder-disordered eating dimensional perspective. [ABSTRACT FROM AUTHOR]

The article presents the discussion on relationship between the emotional state of HCW and environmental variables. Topics include leading to significant concern among HCW precipitating emotional responses of anxiety, depression, and acute stress; and finding significant differences between physicians and other health professionals in all clinical symptoms.

The kinetic behavior of the CuO–ZnO–ZrO 2 (CZZr) and CuO–ZnO–MnO (CZMn) metallic functions in the methanol synthesis step has been studied under suitable operating conditions for DME synthesis, and the values of methanol yield and selectivity have been compared with those corresponding to the conventional CuO–ZnO–Al 2 O 3 (CZA) metallic function. On the other hand, the performance (DME yield and selectivity) of SAPO-18 in the methanol dehydration step has also been compared with the conventional γ-Al 2 O 3 acid function. Based on the kinetic behavior of the bifunctional catalysts with different mass ratios between the metallic and acid functions, a 2/1 ratio has been determined to be suitable in the single-step synthesis of DME. Moreover, the performance of the catalysts in the synthesis of DME has been compared using different reaction conditions (temperature, pressure, CO 2 /CO and H 2 /CO x molar ratios in H 2 + CO + CO 2 feed). The results show the good behavior of the CZZr/S and CZMn/S catalysts for the valorization of CO 2 , since they provide higher DME yield and selectivity than a CZA/γ-Al 2 O 3 catalyst. Although the CZZr/S catalyst has a higher CO 2 sequestration capacity, the lower preparation cost of the CZMn/S catalyst means an incentive for its use. [ABSTRACT FROM AUTHOR]

Carbon-based adsorbents were prepared through the physical activation of sewage sludge with CO2. The effect of the acid treatment was investigated, either before or after the physical activation. The post-washing increases the porosity due to the removal of the inorganic fraction and the improvement in the accessibility of the carbon fraction. The post-washing is essential for high activation temperatures since the high reactivity of CO2leads to a high pore blockage. In fact, the material activated at 900°C has a very low surface area (43 m2/g), while after washing it reaches 654 m2/g. The effect of the acid treatment prior to the physical activation depends on temperature: at 600°C, it results in a huge pore development (mainly macropores), while at 900°C, the microporosity increases. The adsorption capacity is not directly related to the BET surface area. For both adsorbates, the uptake ability depends on the textural properties (it is favoured by mesoporosity for methylene blue (MB) and microporosity for phenol) and surface chemistry (favourable effect of oxygen- and nitrogen-containing functional groups for MB and unfavourable effect for phenol). [ABSTRACT FROM AUTHOR]

Bone is an inorganic template containing organic material inside which can be converted into hydroxyapatite-rich material by pyrolysis. Nowadays, there is a growing research interest in the use of hydroxyapatite, the chemical formula of which is Ca10( PO4)6( OH)2. In the present work, pork bone, an abundant biomass source and food waste, has been converted into structured porous hydroxyapatite by a three-step process including precharring under mild conditions, chemical activation, and thermal activation. The investigated activating agents were Na OH, KOH, K2 CO3, H2 SO4, and H3 PO4. A thorough investigation of the influence of different activating protocols on the chemical and textural properties of the produced material was carried out by nitrogen adsorption-desorption at 77 K, potentiometric titrations, Fourier transform infrared, and X-ray diffraction techniques. Chemical activation with Na OH, K2 CO3, and H2 SO4 increased the specific surface area up to 53%. H3 PO4 reduced both surface area and pore volume, and KOH showed little influence on the pore structure. The produced materials were evaluated by methylene blue adsorption tests and showed significant improvement as a result of chemical activation. As a main effect, acid treatment increased methylene blue adsorption kinetics, probably owing to an increase in micropororosity, whereas alkali activation enhanced the adsorption capacity of the resultant biochar. [ABSTRACT FROM AUTHOR]

Abstract: A kinetic model has been established for the transformation of (H2 +CO2) into dimethyl ether (DME) on a CuO–ZnO–Al2O3/γ-Al2O3 bifunctional catalyst with excess γ-Al2O3 acid function. The model considers the attenuation of methanol synthesis and the formation of paraffin byproducts due to CO2 and water in the reaction medium. Furthermore, the catalyst''s low deactivation (lower than for (H2 +CO) feed) is quantified by means of an equation that considers coke deposition on the metallic function due to the degradation of oxygenates (methanol and DME) in the reaction medium as the cause of deactivation. Deactivation attenuates as water and CO2 concentrations in the reaction medium are increased. The model fits the experimental results for the evolution with time on stream of both CO2 conversion and the yields of DME, methanol and paraffins in the range of operating conditions studied: 225–325°C; 20–40bar; H2/CO2 molar ratio in the feed, between 2/1 and 4/1; time on stream, up to 30h. The following operating conditions are suitable by striking a balance between activity at zero time on stream and deactivation: temperature, 275°C; pressure, 40bar; H2/CO2 molar ratio in the feed, 4/1. [Copyright &y& Elsevier]

Abstract: Co-feeding water with syngas in the direct synthesis of dimethyl ether has been studied in order to reduce the deactivation by coke deposition on the CuO–ZnO–Al2O3 metallic function in the CuO–ZnO–Al2O3/γ-Al2O3 bifunctional catalyst. The runs (synthesis of methanol and synthesis of DME) have been carried out in an isothermal fixed bed reactor under conditions avoiding catalyst deactivation due to the sintering of the metallic function (<325°C) and the deactivation of the acid function (with an excess of γ-Al2O3 in the catalyst). The results of long-term experiments evidence that water in the reaction medium attenuates coke deposition during the methanol synthesis step, which is the limiting one. Water is understood to partially inhibit the formation of coke precursor methoxy ions. Furthermore, the formation of paraffins is attenuated by co-feeding water. [Copyright &y& Elsevier]

Abstract: This paper deals with the regeneration of a CuO-ZnO-Al2O3/γ-Al2O3 catalyst used in the direct synthesis of dimethyl ether. When coke combustion (subsequent to aging treatment) is performed in a thermobalance, two coke fractions with different combustion kinetics are identified. One coke fraction, deposited on the metallic sites and whose combustion is activated by these sites, has a kinetic constant of combustion 7–26 times higher than that corresponding to the coke located at the Al2O3 support. Uninterrupted operation is feasible in reaction–regeneration cycles in a fixed bed reactor as long as the reaction and regeneration steps are carried out at 325°C, which are limiting conditions in order to avoid irreversible deactivation by sintering of the metallic function. The regeneration with O2 diluted with He (5% of O2) allows the complete combustion of coke. Under conditions of partial coke combustion it is observed that the removal of the fraction deposited on the metal makes it possible to recover the initial activity of the catalyst, which subsequently undergoes fast deactivation. [Copyright &y& Elsevier]

A kinetic model has been established for the deactivation of a CuO−ZnO−Al2O3/γ-Al2O3catalyst in the direct synthesis of dimethyl ether. The model allows calculating the effect of the operating conditions and the evolution of component concentration in the reaction medium (dimethyl ether, methanol, paraffins, H2, CO, CO2, and H2O) with time on stream. The results of the model fit the experimental results in a wide range of conditions: 225−350 °C; 10−40 bar; space time, 0.1−68.0 (g of catalyst) h (mol of reactants)−1; molar ratio (H2/CO) in the feed, 2−4; time on stream, 30 h. The model considers the cause of deactivation to be coke deposition on the metallic function and that this coke is formed by degradation of oxygenates (dimethyl ether and methanol). The effect of water in the reaction medium has been quantitatively considered in the kinetic model, whose drawback is the attenuation of the methanol synthesis rate and whose benefit is the attenuation of deactivation by coke deposition. The kinetic model is useful for predicting the influence of water in the feed with syngas as a strategy to attenuate deactivation, which is insignificant for a H2O/(H2+ CO) molar ratio of around 0.20, although it causes a slight decrease in initial catalyst activity. [ABSTRACT FROM AUTHOR]