Osmotic dehydration (OD) is one of the conventional methods to increase the shelf-life of vegetables and fruits. However, the operating conditions can adversely affect the organoleptic and nutritional quality of fresh products due to the high sugar uptake during processing and the loss of water-soluble constituents to the osmotic medium. The application of edible films has attracted interest due to their ability to reduce the entry of solutes and simultaneously increase the removal of water during OD treatments. Microwave (MW) is one of the most effective emerging technologies to accelerate dehydration processes in vegetable matrices. This aspect is particularly relevant in strawberries, given its high content in bioactive and nutritional compounds. Thus, the aim of this paper was to assess the influence of edible film application (alginate–lactate) in strawberry slabs during combined OD-microwaves dehydration processes. Samples of 1?cm thickness were treated with sucrose solution (60°Bx, 40?°C, 4?h) and then were dehydrated in a microwave oven (1.2?W/g). The application of alginate–lactate edible films resulted in similar weight and water losses but lower solids gain compared to uncoated samples during OD treatment. OD pre-treated MW-dried strawberry slabs with moisture contents up to 0.15?kg dry basis were obtained after 100?min of MW drying. Besides, the effective diffusional coefficient (De) was estimated for MW drying process, values ranged from 4.5 to 8.8 10?10 m2/s when shrinkage effect was considered, and from 1.1 to 2.3 10?9 m2/s for constant thickness assumption. 相似文献
Graphite exfoliation by shear‐induced dry and wet processes and especially mechanochemistry represent attractive routes to carbon nanofillers. Dry ball‐milling of graphite in a planetary mill under gas pressure is a scalable and environmentally benign one‐step process, which requires neither hazardous solvents nor tedious separate functionalization and purification steps. Gas type, pressure, and milling duration govern average particle size, shape, and functionalization. Ball‐milling under Ar yields hydroxylated spherical carbon particle agglomerates, whereas ball‐milling under CO2 affords functionalized nanoplatelets without encountering agglomeration problems and highly exothermic post‐milling reactions with air. The carboxylation of graphene nanoplatelets enhances their dispersibility in various media including polypropylene (PP) even in the absence of compatibilizers. Large amounts of carboxylated nanoplatelets are dispersed in PP without massive viscosity build‐up. Functionalized carbon nanoplatelet fillers enable tailoring of recyclable lightweight carbon/hydrocarbon composites exhibiting an improved balance of stiffness, strength, toughness, electrical, and thermal conductivity. 相似文献
The reaction of diorganyl disulfides or diselenides with PhICl2 in DMF at room temperature led to the in situ formation of the reactive organosulfenyl chloride (RSCl) or selenenyl chloride (ArSeCl), which reacted with enaminone compounds to afford a series of α‐thioenaminones or α‐selenylenaminones, respectively, including the bioactive inhibitor for Cdc25B and its analogue, via the intermolecular oxidative C(sp2)‐S/Se cross coupling reactions under metal‐free conditions.
A recent contribution to the ongoing debate concerning the concept of usability and its measures proposed that usability reached a dead end – i.e. a construct unable to provide stable results and to unify scientific knowledge. Extensive commentaries rejected the conclusion that researchers need to look for alternative constructs to measure the quality of interaction. Nevertheless, several practitioners involved in this international debate asked for a constructive way to move forward the usability practice. In fact, two key issues of the usability field were identified in this debate: (i) knowledge fragmentation in the scientific community, and (ii) the unstable relationship among the usability metrics. We recognise both the importance and impact of these key issues, although, in line with others, we may not agree with the conclusion that the usability is a dead end. Under the light of the international debate, this work discusses the strengths and weaknesses of usability construct and its application. Our discussion focuses on identifying alternative explanations to the issues and to suggest mitigation strategies, which may be considered the starting point to move forward the usability field. However, scientific community actions will be needed to implement these mitigation strategies and to harmonise the usability practice. 相似文献
The identity of the Carménère variety was lost in Chile and regarded as a Merlot grape. This grape disappeared in Bordeaux, France, the country of origin of the grape, because of the phylloxera plague. In the present paper, a study on the classification of Chilean Carménère and Merlot wine samples based on chemical parameters was carried out. A total of 64 samples were analysed, and 20 chemical parameters were determined. Forty‐five samples were labelled as “Carménère” and 19 samples as “Merlot” according to the wine label. The samples were preprocessed with sampling algorithms to double the number of Merlot samples to 38 and reduce the Carménère samples to 38. The dataset was analysed with the data mining techniques support vector machines and correlation‐based feature selection. The capability of classifying the samples with all 20 chemical parameters was 86.8% accurate, and when using only the variables a*, total anthocyanins, cyan‐3‐glu, malv‐3‐acetylglu, peon‐3‐acetylglu, and vitisin A, which were selected through correlation‐based feature selection, accuracy increased to 93.4%. Therefore, wine anthocyanins and the parameter a* of wine colour proved useful to discriminate the wines. 相似文献
In the processing industry, frequent faults call for assistance in diagnosis, and case‐based reasoning (CBR) can provide solutions applied by other operators in the past. This study investigated whether salient case ratings promote an uncritical acceptance of solutions. In 2 experiments, subjects diagnosed faults with a simulated CBR system, and ratings were presented in graphical or verbal format. In most trials, the case with the highest rating provided the correct solution, while in catch‐trials, it did not. Graphical ratings were hypothesized to speed up solutions but discourage cross‐checking and lead to errors in catch‐trials. These hypotheses were not confirmed, even though Experiment 2 maximized the incentive of relying on case ratings. While graphical ratings led subjects to start with the most highly rated case, they did not impair situation analysis and accuracy. The results suggest that during fault diagnosis people are not easily misled into overtrusting a CBR system. 相似文献
This article shows the role that fuzzy sets may play in the prospect of analysing qualitative data. To underline this role, a human-computer interaction (HCI) study is presented. The data coming from 20 experts concerns their judgment regarding 33 questions related to the use of HCI approaches in order to support interactive system development phases. Each response scale features three main modalities, that is Agree, Partially agree and Disagree. The dataset example is analysed using multiple correspondence analysis (MCA) with both crisp and fuzzy coding models where the intermediate modality, Partially agree, is removed and considered with ½ membership values to the two extreme modalities. A comparative analysis is performed and the discussion states the interest of fuzzy coding with several kinds of qualitative factors or measurement variables. With qualitative measurement variables (our example), the main drawback of fuzzy coding could be the information loss, which is counterbalanced by the possibility of having fewer modalities and therefore of simplifying the multivariate analysis. 相似文献
