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Abstract Poor reconstitution of food powders is a defect that hampers the development of novel dehydrated food products. In order to improve the quality of a powdered food during the development stages, a better understanding of how the powder behaves upon rehydration is vital. However, common methods to follow powder reconstitution, e.g. conductimetry, can yield uninterpretable results, especially if a powder does not completely wet, sink, disperse and dissolve. To circumvent this problem, a mapping approach was developed to describe the powder behavior depending on the combinations of variables. To construct such a map, powders are reconstituted using a transparent vessel, and an optical recording of each trial is utilized to describe if the process was ‘normal’, i.e. if wetting/sinking, dispersing, and dissolving of the particles occur readily and more or less sequentially, or if it was limited by poor powder sinking, by sedimentation, slow material dissolution, or lump formation. By mapping the behaviors at different combinations of temperatures and agitation speeds, various regimes of limiting reconstitution behavior can be identified. In the current study, rate-limiting regime maps of four types of maltodextrin (Glucidex DE21, IT21, DE6, and IT6) are constructed and compared in order to investigate the influence of molecular weight, particle size, water temperature, and agitation speed on the rehydration of a water-soluble amorphous food powder. Such a study would not have been possible using conventional techniques, as powder reconstitution is not always complete.

This study investigates human-building interaction in office spaces across multiple countries including Brazil, Italy, Poland, Switzerland, the United States, and Taiwan. We analyze social-psychological, contextual, and demographic factors to explain cross-country differences in adaptive thermal actions (i.e. cooling and heating behaviors) and conformity to the norms of sharing indoor environmental control features, an indicator of energy consumption. Specifically, personal adjustments such as putting on extra clothes are generally preferred over technological solutions such as adjusting thermostats in reaction to thermal discomfort. Social-psychological factors including attitudes, perceived behavioral control, injunctive norms, and perceived impact of indoor environmental quality on work productivity influence occupants’ intention to conform to the norms of sharing environmental control features. Lastly, accessibility to environmental control features, office type, gender, and age are also important factors. These findings demonstrate the roles of social-psychological and certain contextual factors in occupants’ interactions with building design as well as their behavior of sharing environmental control features, both of which significantly influence building energy consumption, and thus, broader decarbonization.

Pathogens represent a significant threat to human health leading to the emergence of strategies designed to help manage their negative impact. We examined how spiritual beliefs developed to explain and predict the devastating effects of pathogens and spread of infectious disease. Analysis of existing data in studies 1 and 2 suggests that moral vitalism (beliefs about spiritual forces of evil) is higher in geographical regions characterized by historical higher levels of pathogens. Furthermore, drawing on a sample of 3140 participants from 28 countries in study 3, we found that historical higher levels of pathogens were associated with stronger endorsement of moral vitalistic beliefs. Furthermore, endorsement of moral vitalistic beliefs statistically mediated the previously reported relationship between pathogen prevalence and conservative ideologies, suggesting these beliefs reinforce behavioural strategies which function to prevent infection. We conclude that moral vitalism may be adaptive: by emphasizing concerns over contagion, it provided an explanatory model that enabled human groups to reduce rates of contagious disease.

A key concern for the safe operation of polymer electrolyte water electrolysis (PEWE) cells is the high hydrogen gas crossover that can lead to explosive hydrogen-oxygen gas mixtures. The safety aspect is especially important with thin membranes, high differential pressures and low current densities. Pt particles incorporated into the membrane catalyze the recombination of H-2 and O-2 to water and lower the content of hydrogen in the oxygen product stream. So far, different approaches have been taken for Pt distribution over the membrane's cross-section to suppress the hydrogen gas crossover: interlayer distribution, border distribution and uniform distribution. This work reports that only border-distributed Pt and uniformly-distributed Pt allow PEWE operation over a satisfying current density range for an extrapolated cathodic pressure of 30 bar(a). Uniform Pt reduction allows a 50% larger operational range than Pt deposition at the border. Further, it is found that reduction of the Pt content in the membrane from 0.06 to 0.01 mg cm(-2) does not allow satisfactory gas crossover suppression. Journal of the Electrochemical Society, 168 (10) ISSN:0013-4651 ISSN:1945-7111

Aggregations of demand response resources can provide a variety of services to the power grid. To utilize them effectively, for both planning problems and real-time control, we must estimate their flexibility. However, flexibility estimates are uncertain because of issues such as model error and forecasting error. In this paper, we present a model of uncertain flexibility and describe the many causes of uncertainty. We conduct two case studies, one for electric vehicle aggregations and one for air conditioner aggregations, in order to show specific examples that illustrate the causes and magnitude of uncertainty. We find that uncertainty can be very large for small load aggregations, when models do not capture enough of the underlying dynamics, or when forecasts of other quantities, such as ambient conditions, are bad. Although the focus of the paper is on understanding uncertainty, we also briefly discuss how one might use knowledge of uncertainty distributions in planning problems to derive closer-to-optimal results.

Abstract The precipitation and separation performance of various binary type 1 salt–water mixtures was systematically studied for the first time in a continuously operated laboratory plant. The aim was to find a field of operation for the salt separator where salts can be separated with high efficiency. Experiments with aqueous solutions of the salts NaNO3, KNO3, Ca(NO3)2, K2CO3, KHCO3, (NH4)2CO3, K3PO4, K2HPO4, KH2PO4, NaCl, KCl, NH4Cl and (NH4)2SO4 were carried out at 30 ± 0.5 MPa varying the salt separator temperature from sub-critical to supercritical. For most of these salts separation efficiencies ranging from 80 to 97% were obtained. For the nitrates the separation efficiency increased in the order NaNO3

Abstract The Kramers Kronig (KK) relations are applied to locally resolved impedance data as obtained from a simple, analytic ‘down the channel’ impedance model of a polymer electrolyte fuel cell (PEFC) air cathode. It is shown that the transport and superposition of oxygen concentration oscillations in gas flow direction can lead to non-causal local cell impedance spectra, while the calculated local cell admittance always fulfills the KK relations. This is explained by the homogeneous distribution of the ac perturbation voltage over the electrode area due to the high electrical conductivity of the bipolar plates. Hence, the KK relations must be applied to the locally resolved admittance data of PEFCs to check if the measured spectra can be a physical response of the system.