Determination of pizzas quality and acceptability by physic-mechanical tests.

The growing need for developing more efficient and sustainable technologies for the processing of bakery products leads to the need for replacing the current subjective methodology by an instrumental method to evaluate the quality of these products. In this work, relevant physic characteristics that define the quality and acceptability of pizzas were identified, and instrumental methods were established to evaluate them. Cooking quality of the pizza base was established through rapid visco analysis and scanning electron microscopy. The physic attributes considered of the pizza base with and without toppings were final cooking temperature, specific volume, water content, color, and texture. Aiming to validate the applicability of the instrumental methods, we prepared well-accepted pizzas, using three different oven technologies, and carried out a sensory test with 60 non-trained panelists. We observed that the proposed method is sensitive enough to identify differences in the quality of pizzas produced by the oven technologies. However, those variations were not enough to be recognized by participants of the sensory panel. The values of pizza attributes obtained in this work could be used as a baseline of comparison for pizzas produced by new and more efficient cooking technologies. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at (10.1007/s13197-021-05148-8).

Wireless data transmission from inside electromagnetic fields.

This paper describes analytical and experimental work developed to evaluate the effects of the electromagnetic fields produced by high-voltage lines (400 kV) on wireless data transmission at the 900MHz band. In this work the source of the data transmission is located inside the electromagnetic field and the reception station is located at different distances from the power lines. Different atmospheric conditions are considered.

Real-world emissions of in-use off-road vehicles in Mexico.

Off-road vehicles used in construction and agricultural activities can contribute substantially to emissions of gaseous pollutants and can be a major source of submicrometer carbonaceous particles in many parts of the world. However, there have been relatively few efforts in quantifying the emission factors (EFs) and for estimating the potential emission reduction benefits using emission control technologies for these vehicles. This study characterized the black carbon (BC) component of particulate matter and NOx, CO, and CO2 EFs of selected diesel-powered off-road mobile sources in Mexico under real-world operating conditions using on-board portable emissions measurements systems (PEMS). The vehicles sampled included two backhoes, one tractor, a crane, an excavator, two front loaders, two bulldozers, an air compressor, and a power generator used in the construction and agricultural activities. For a selected number of these vehicles the emissions were further characterized with wall-flow diesel particle filters (DPFs) and partial-flow DPFs (p-DPFs) installed. Fuel-based EFs presented less variability than time-based emission rates, particularly for the BC. Average baseline EFs in working conditions for BC, NOx, and CO ranged from 0.04 to 5.7, from 12.6 to 81.8, and from 7.9 to 285.7 g/kg-fuel, respectively, and a high dependency by operation mode and by vehicle type was observed. Measurement-base frequency distributions of EFs by operation mode are proposed as an alternative method for characterizing the variability of off-road vehicles emissions under real-world conditions. Mass-based reductions for black carbon EFs were substantially large (above 99%) when DPFs were installed and the vehicles were idling, and the reductions were moderate (in the 20-60% range) for p-DPFs in working operating conditions. The observed high variability in measured EFs also indicates the need for detailed vehicle operation data for accurately estimating emissions from off-road vehicles in emissions inventories. IMPLICATIONS: Measurements of off-road vehicles used in construction and agricultural activities in Mexico using on-board portable emissions measurements systems (PEMS) showed that these vehicles can be major sources of black carbon and NOX. Emission factors varied significantly under real-world operating conditions, suggesting the need for detailed vehicle operation data for accurately estimating emissions inventories. Tests conducted in a selected number of sampled vehicles indicated that diesel particle filters (DPFs) are an effective technology for control of diesel particulate emissions and can provide potentially large emissions reduction in Mexico if widely implemented.