Shape memory behavior of Ti–Ta and its potential as a high-temperature shape memory alloy

In this study, the effect of Ta content on shape memory behavior of Ti–Ta alloys was investigated. The shape memory effect was confirmed in Ti–(30–40)Ta alloys. The martensitic transformation start temperature (M_s) decreased by 30 K per 1 at.% Ta. The amount of ω phase formed during aging decreased with increasing Ta. A stable high-temperature shape memory effect was confirmed for Ti–32Ta (M_s = 440 K) during thermal cycling between 173 and 513 K. On the other hand, the high-temperature shape memory effect of Ti–22Nb, which has a similar M_s to Ti–32Ta, exhibited poor stability due to the large amount of ω phase formed during thermal cycling. It is suggested that Ti–Ta is an attractive candidate for the development of novel high-temperature shape memory alloys.     

Approaching PM(2.5) and PM(2.5-10) source apportionment by mass balance analysis, principal component analysis and particle size distribution

A chemical characterization was carried out for PM(2.5) and PM(2.5-10) samples collected in a suburban area and the concentrations of 12 elements were determined in 8 size segregated fractions using a Berner Impactor. Two main objectives were proposed in this work: 1) to test for closure among chemical and gravimetric measurements of PM(2.5) and PM(2.5-10) and 2) evaluate the performance of Multilinear Regression Analysis (MLRA) and Mass Balance Analysis (MBA) in the determination of source contribution to Particulate Matter (PM) concentrations. The fraction unaccounted for by chemical analysis comprised on average 17% and 34% of gravimetric PM(2.5) and PM(2.5-10), respectively. The lack of closure in PM(2.5) and PM(2.5-10) mass (i.e., constituent concentrations not adding up to gravimetrically measured) could partly result from the presence of water associated with particles and errors in the estimation of unmeasured species. MLRA and MBA showed very similar results for the temporal variation of the source contributions. However, quantitatively important discrepancies could be observed, principally due to the lack of mass closure in PM(2.5) and PM(2.5-10). Both methods indicated that the major PM(2.5) aerosol mass contributors included secondary aerosol and vehicle exhaust. In the coarse fraction, marine and mineral aerosol contributions were predominant.     

Reaction Pathways in the Reduction of NO x Species by CO over Pt–Ba/Al2O3: Lean NO x Trap Catalytic Systems

The reduction by CO of NO _x species stored over Pt–Ba/Al₂O₃ Lean NO _x Trap systems is analysed in this work. The reaction mechanisms and pathways leading to N₂ formation both under dry and wet conditions are investigated by complementary transient dynamic experiments and FTIR analyses.     

Dominant Reaction Pathways in the Catalytic Partial Oxidation of CH4 on Rh

Reforming technologies are at the heart of converting fossil fuels and biofuels to syngas and hydrogen for novel energy applications and, among reforming technologies, catalytic partial oxidation is appealing for decentralized energy production due to the compactness of reactors. Yet, the mechanisms of these reactions are poorly understood. Here we combine fundamental surface chemistry and detailed reactor models to elucidate the pathways leading to syngas and propose strategies for optimizing the process.     

Assessment of air pollution sources in an industrial atmosphere using principal component and multilinear regression analysis

Aerosol samples collected in the industrial area of Estarreja, Portugal, were used to assess the source classes responsible for the particulate levels observed in the local atmosphere. Principal Component Analysis was applied separately to the concentrations of aerosol constituents and meteorological variables to obtain the number of Principal Components and to verify the influence of weather conditions on ambient air quality. The technique led to the conclusion that soil and transport emissions represent important aerosol sources even in this industrial environment. The quantitative contribution of each source class was calculated using Multilinear Regression Analysis; 37% of the aerosol mass had a soil origin, 8% was from sea spray, 18% resulted from transport emissions and 24% contained ammonium salts. Twelve percent of total suspended particle (TSP) mass could not be explained by any of the six Principal Components retained. Ammonium salts and two other minor Principal Components seem to result mainly from industrial emissions. More specific information about the contribution of each particular source was not possible with this technique.     

Functional Beverages: The Emerging Side of Functional Foods

In recent times, there has been growing recognition of the key role of foods and beverages in disease prevention and treatment. Thus, the production and consumption of functional foods has gained much importance as they provide a health benefit beyond the basic nutritional functions. At present, beverages are by far the most active functional food category because of convenience and possibility to meet consumer demands for container contents, size, shape, and appearance, as well as ease of distribution and storage for refrigerated and shelf‐stable products. Moreover, they are an excellent delivering means for nutrients and bioactive compounds including vitamins, minerals, antioxidants, ω‐3 fatty acids, plant extracts, and fiber, prebiotics, and probiotics. However, in most cases, specific concerns have been raised over their safety. This review reports on the scientific advances in the emerging area of functional beverages with a focus on commercially available products, as well as on the potential health benefits related to their consumption.     

Influence of Subtropical Region Strawberry Cultivars on Jelly Characteristics

At the end of the production period of strawberries grown in subtropical regions, postharvest durability is severely diminished due to rising temperatures which compromises the commercialization of fresh fruit. An ideal option would be to process strawberries in the form of preserves, jams, and jellies. Along this line it becomes extremely important to conduct a survey of which cultivars grown in subtropical regions are more suitable for processing in the form of jelly, as well as to understand what the consumer profile is for this product. The objective of this study was to evaluate the influence of different strawberry cultivars grown in subtropical regions of Brazil (Camarosa, Festival, San Andreas, Oso Grande, Camino Real, and Albion) on the physicochemical characteristics, rheological properties and sensory acceptance of the resulting jelly in order to identify cultivars with the greatest potential for industrial use. The strawberry cultivars presented different physicochemical characteristics which resulted in jellies with different physicochemical and rheological characteristics. In this study, however, we verified that all cultivars have potential to be processed in the form of jelly due to good acceptance of all formulations prepared. In general consumers prefer a lighter‐colored strawberry jelly, with a less intense red color, more acidic, and less consistent/firm.     

Influence of processing on the antioxidant capacity and bioactive compounds in jellies from different blackberry cultivars

The effect of thermal processing and the berry cultivar has been the subject of several studies, to serve as a basis for the least possible loss of bioactive compounds and antioxidant capacity. In Brazil, there are numerous blackberry cultivars under cultivation, and in this context, the aim of this work was to study how the bioactive compound contents and antioxidant capacity of blackberry jelly were influenced by the cultivars (Guarani, Brazos, Comanche, Tupy, Cherokee, Caingangue and Choctaw). Analysis was made of 7 fresh blackberry cultivars and 7 blackberry jelly formulations. Analysis of antioxidant activity, total phenolics, total anthocyanins and ascorbic acid was performed. It was verified that the contribution of the heat sensitive antioxidants compounds is considerable in all blackberry cultivars, and the degradation of these compounds was significantly different between the different blackberry cultivars. The Brazos and Caingangue cultivars stand out as undergoing the lowest losses in processing, resulting in jellies richer in bioactive compounds and higher antioxidant capacity.     

Improved loquat (Eriobotrya japonica Lindl.) cultivars: Variation of phenolics and antioxidative potential

Leaves and fruits (peel and flesh) of six improved cultivars (‘Mizuho’, ‘Néctar de Cristal’, ‘Mizauto’, ‘Mizumo’, ‘Centenária’ and ‘NE-3’) of loquat (Eriobotrya japonica Lindl.) were studied for their phenolic composition and antioxidant capacity. The analysis by HPLC-DAD-ESI-MS/MS allowed the identification of 18 compounds (8 hydroxycinnamic acid derivatives and 10 flavonoid glycosides). The quantification of the identified compounds revealed distinct profiles amongst the three analysed materials. Loquat leaves exhibited the lowest amounts of phenolics. 3- And 5-caffeoylquinic, and 5-feruloylquinic acids were the major compounds. Generally, ‘Mizauto’ cultivar presented the highest phenolic content. All loquat materials exhibited DDPH scavenging capacity, in a concentration-dependent manner, the leaves being the most active one. This effect seems to be related to the flavonoid content.     

The role of conching in chocolate flavor development: A review

Chocolate is an indulgent product whose consumption is mostly motivated by its alluring sensory properties. Among them, flavor stands as the key driver for consumer preference and purchase intention. Flavor is a complex multimodal perception whose discrimination depends mostly on the retronasal aromas associated with the presence of odor-active compounds in the matrix. The development of chocolate flavor relies on several factors, ranging from intrinsic properties of raw materials to formulation and processing conditions. As the last step of liquid chocolate manufacture, conching develops proper fluidity/texture and finetunes flavor, by means of intensive mixing and continuous heating of chocolate mass for several hours. Time and temperature are the main parameters determining the extent of conching effects upon flavor, despite factors such as ventilation, energy input onto chocolate mass, and configuration of conching machine being also relevant to some of the physicochemical mechanisms involved in flavor modification. Overall, conching impacts chocolate flavor by either changing the concentration of key odor-active compounds or modifying their distribution throughout the matrix, affecting their binding to other components and, ultimately, their rate of release during ingestion. The present review aims to gather evidence on the physicochemical transformations promoted by conching responsible for flavor enhancement and overall sensory quality of chocolates.