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This work describes a bibliometric analysis of recent articles addressing the applications of thermal processing in foods, as well as its effect on their physicochemical and rheological properties. The analysis involved utilizing the software tools VOSviewer and RStudio to map the knowledge domain. Initially, 665 articles from peer-reviewed journals were retrieved, but only 92 (13.8%) of them discussed thermal processing related to fruit applications and were published in indexed journals. However, this number was further narrowed down to 35 (5.3%) articles specifically focused on the target subject. A rigorous appraisal of these 35 articles allowed it to be classified according to its aim, kind of fruit used, thermal processing treatment, and its rheological, physicochemical, and other properties. The leading countries in the general area of food thermal processing research according to documents and citations were China, USA, Brazil, India and Spain. It is important to highlight that conventional thermal processing continues to be investigated for applications in fruits; on the other hand, it is expected that the use of unconventional or emerging technologies will bring significant advances to the food industry in the future. [ABSTRACT FROM AUTHOR]

Understanding and characterizing the relationship between soil and environmental temperatures is crucial for developing effective agricultural management strategies, promoting natural resource conservation, and developing sustainable production systems. Despite the direct impact of the thermal properties of Oxisols on global food production and sustainable agriculture, there is a dearth of research in this area. Therefore, this study aimed to monitor and analyze the thermal behavior of a Red Latosol (Oxisol) in Dracena-SP, Brazil, over two years (from 28 July 2020 to 27 July 2022). Using R software (version 4.3.0) and paired group comparisons, we organized the data into twelve-month sets to estimate monthly soil thermal diffusivity using amplitude, arctangent, and logarithm methods. Soil depth and thermal amplitude showed a temporal pattern characterized by inversely proportional magnitudes that followed an exponential behavior. The thermal amplitude of the Oxisol evaluated decreased with increasing depth, indicating soil thermal damping. In conclusion, the relationship between Oxisol and environmental temperature has significant implications for achieving sustainable agriculture and efficient water and plant resource management. [ABSTRACT FROM AUTHOR]

The search for cleaner production technologies and sustainable development tools has prompted increasing interest in the use of new, renewable raw materials for biorefineries and energy production. Thus, biodiesel production from the pulp oil (fruit oil) of Acrocomia totai Mart., a species of palm tree, is currently being investigated. However, the bioenergy potential of biomass from different parts of this species is still unknown, and may not be limited to oil from the pulp. Therefore, the aim of this work was to evaluate the leaves of A. totai as a secondary source of lipids and energy. Deciduous and fresh leaves were submitted to the Soxhlet and Bligh & Dyer extractions, and the presence of 1.0 to 5.8% of unsaturated fatty acids was observed by GC-FID analyses. The crude extract (CE) of the leaves was obtained by exhaustive extraction with methanol and then partitioned with different solvents. CE and its fractions were characterized by 1H nuclear magnetic resonance (NMR) spectroscopy, and the thermal properties were determined. The average specific heat of the grease fractions was 2.0 J g−1 K−1 and the calorific value of the polar and non-polar fractions varied from 15.7 to 34.1 MJ kg−1. For the whole leaves, the calorific value of the deciduous leaves was higher than that of the fresh leaves due to their lower water content, as determined by thermogravimetric-differential thermal analyses (TG-DTA) and infrared (IR) spectroscopy. The residual pies from the Soxhlet extractions of the deciduous and fresh leaves were characterized by TGA-DTA and scanning electron microscopy (SEM), revealing a lignocellulosic fibrous material with calorific values of 14.2 MJ kg−1 and 9.3 MJ kg−1, respectively, and an average specific heat of 1.6 J g−1 K−1. These thermal properties are comparable to those of sugarcane bagasse, a widely used type of biomass for industrial large-scale bioenergy production in Brazil. Therefore, these results indicated that it may be possible to harvest the deciduous leaves, a residue from the "macaúba" cultivation, for energy cogeneration in biodiesel refineries. [ABSTRACT FROM AUTHOR]

The present work aimed to determine the physicochemical and thermal properties of sugarcane Dry Cleaning System Residue(DCR) and Bagasse from milling A(BMA) and B(BMB), aiming the cogeneration system application. The DCR and BMB are obtained after the Dry Cleaning System, currently used during the mechanized harvesting implemented in Brazil. The DCR under treatment is obtained as chopped sugarcane Straw (CSS), which together with the BMA and BMB are brought to the boiler, without considering yet the alterations that can have on that system. Accordingly, CSS, BMA and BMB were undergone analysis to determine their particle size, ultimate, proximate and elemental ash composition, bulk density and Higher Heating Value (HHV). The results indicate that CSS, BMA and BMB have a higher ash content 11.19 wt%, 2.08 wt% and 1.06 wt%, and lower fixed carbon content 11.54 wt%, 10.29 wt% and 8.92 wt%, respectively, in relation to the bagasse. HHV for CSS was 6.67 MJ kg−1, 18.59 MJ.kg-1 for BMA and 18.43 MJ kg−1 for BMB, being close to the 18.89 MJ.kg-1 of the bagasse. This, enables the addition of DCR along with BMA and BMB in bagasse cogeneration plants, but it can cause a fouling and slagging effects due of the presence of ashes with high content of alkali minerals. • Characterization of sugarcane dry cleaning system residues for combustion, are showed. • Dry Cleaning System (DCS) can improve bagasse properties as a biomass for combustion. • Chopped Sugar Straw (CSS) combustion properties are impaired after DCS pretreatment. • Mechanical harvesting and DCS change sugarcane residues properties for cogeneration. [ABSTRACT FROM AUTHOR]

Brazil is a country with different biomes and the Cerrado is known for its rich resources and flora. Among the fruits in the Cerrado, we can highlight the tamarindeiro, whose fruit, tamarind, exhibit excellent nutritional quality. Tamarind is enough explored on the continent of origin (Africa), however surveys involving all utilities of the plant are still insignificant. So, the objective of the work was to characterize shells, pulp and tamarind seeds of the Cerrado, Goiás, as to physico-chemical, technological and thermal properties. The collected fruits obtained average proportions of 22,2 ± 1,1% shells, 44,0 ± 2,4% pulp and 14,4 ± 1,6% seeds, and approximately 20% fibers. It presented high carbohydrate content and low water activity for the three portions and lower values of ash, lipids and proteins. The shell and seed flours presented high content of total dietary fiber and fruit pulp presented acid pH (3,02 ± 0,01) and high titratable acidity (29,82 ± 0,24). The seed flour had a water absorption and solubility index greater than the shell flour, and lower oil absorption index. The tamarindo pulp presented 4 peaks in your thermogram, being the first relative to the gelatinization of starch, 2 and 3 peaks suggested the formation of carbohydrate-lipid complexes and protein denaturation and 4 peak the glass transition. Tamarind shell and seed flour showed similar behavior to pulp after 115 °C, with 2 endothermic peaks. Concluded that the integral tamarind fruit has specific physico-chemical, nutritional, thermal and technological characteristics and suitable for use in the food industry. [ABSTRACT FROM AUTHOR]

The application of cashew gum, in particular the one which is abundant in northeastern Brazil, remains limited to the foods and pharmaceutics industry. In attempting to obtain further potentialities of the cashew gum (CG), its electrical applicability needs to be explored. To this end, the CG is incorporated in blends based on PANI to make an innovative thin self-sustainable blend films (PACG) comprising PANI and CG. The blend films were fabricated by adding the CG in the synthesis process of the polyaniline, and they were prepared by the standard "casting" method. The film materials were blending in three different weight ratios (99:1), (95:5) and (80:20). We also fabricated the only PANI film. As PANI has its conductivity enhanced by doping process, the blends and PANI films were doped by using sulfuric acid at 0.05 and 0.1 mol L−1 concentrations. The characterization of the films was carried out by FTIR spectroscopy, thermal analyses and electrical measurements. The FTIR results exhibited the occurrence of a weak and secondary chemical interaction between PANI and CG. Once there was no appearance of new bands, the profile of the FTIR curves was maintained for the blends and no significant shifts were identified for the maximum frequency of bands. The thermal analysis measurements revealed alteration at the thermal stability temperature of blends due to the doping process and indicated that the thermal profile of the constituent materials (PANI and CG) was preserved in the blends. The electrical studies showed that the undoped blend films exhibited a low level of conductivity as the amount of gum increased. On the other hand, the doped films reached a high level of conductivity in comparison with PANI films and the more the amount of CG in the blend the more is its conductivity. For PACG with 20% of gum, σ increased by a factor of 106, whereas in PANI film, it increased by 104 at the 0.1 mol L−1 doped level. These results point to the possibility of using this sort of blend based on polyaniline and cashew gum as an innovative conductive polymer once it exhibits acceptable electrical, structural and thermal properties. [ABSTRACT FROM AUTHOR]

• We used models of heat transfer by conduction and convection to estimate soil thermal properties. • We used 1.5 years of experimental data on a natural pasture area in the Pampa biome in southern Brazil. • We consider the effects of soil heterogeneity and thermal convection due to the vertical movement of water in the soil, W. • Soil thermal diffusivity (k) showed an inverse seasonal variation with soil temperature. • Increasing values of W led to an increase in the variability of k with depth. Soil temperature, composition, and structure directly affect the heat transfer mechanisms in soil. Understanding the thermal behavior of soil is fundamental for describing the processes of mass and energy exchange in the soil-plant-atmosphere system. In addition, estimating thermal property values is necessary to determine the amount of heat transferred, stored, or transmitted by conduction and convection between the soil surface and deeper layers. This study used two soil heat transfer models (the conduction and conduction-convection methods) to estimate soil thermal properties. Soil data were collected in a natural pasture area in the Pampa biome in southern Brazil over 1.5 years. The results showed that soil thermal diffusivity (k) has an inverse seasonal variation with soil temperature (T s). The k and soil thermal conductivity (λ) values are higher as the soil depth and soil moisture (θ) increase, confirming the vertical variation of thermal properties. The liquid water flux density (W) represents the vertical movement of water in the soil and decreases in periods of higher T s. Increasing values of W led to an increase in the variability of k with depth. The conduction–convection method provides the best estimates for T s with R2 = 0.99 for deeper layers compared to the conduction method. However, we found that both models gave similar results for near-surface layers since, in this case, the conduction process was responsible for most of the heat transfer from the surface to the ground. The results obtained here allowed us to evaluate heat transfer at different depths and estimate thermal properties as a function of soil moisture in a natural pasture area in the Brazilian Pampa biome. Furthermore, the results can be integrated into global land surface models intended to represent the behavior of the energy exchange between soil, surface, and atmosphere. [ABSTRACT FROM AUTHOR]

In Brazil, studies to reuse construction and demolition waste are a special issue because a large amount of this material has been delivered to the public landfills and in illegal places. Some researchers have suggested reusing this material in building elements, such as bricks or blocks. It is possible to find a lot of researches in physical/ mechanical characterization, while little effort has been made to characterize recycled construction and demolition waste blocks (RCDW) for their thermal properties. The aim of this work was to characterize the RCDW thermal resistance and conductivity in order to provide subsidies for a building's thermal performance analysis. The hot-box method was adapted, together with measuring techniques with a heat-flow meter to determine the RCDW thermal properties. The results indicated that the RCDW block overall thermal resistance and thermal conductivity in the solid region was within the intervals of 0.33≤RT≤0.41m²KW-1 and 0.60≤λ≤0.78Wm-1K-1, respectively. The lower resistance and conductivity values are justified by the presence of aggregate with a lower density and lower thermal conductivity than the natural aggregate. [ABSTRACT FROM AUTHOR]

Starches isolated from six maize landraces from Brazil were investigated for their physicochemical, morphological, structural and thermal properties and compared to a commercial maize starch (COM). Similarities (chemical composition) and differences (structural characteristics) were observed. The crystallinity of starches ranged between 18.5 and 25.0%. The swelling power at 65°C ranged between 3.00 g/g Pires (PIR) and 4.82 g/g Mato Grosso (MT), whereas at 90°C varied between 18.8 g/g (PIR) and 23.9 g/g (MT), differing from COM, i.e., 14.6 g/g. The starch granule's morphology and size determined by SEM showed polyhedral and spherical shapes and a heterogeneous size distribution between 1.7 and 25 µm. The gelatinization process studied by DSC showed that transition temperatures ( T0, Tp, Tc) ranged between 61.0-65.9, 67.5-71.7, and 75.2-76.8°C, respectively, and enthalpies (Δ Hgel) between 11.4 and 13.3 (J/g). The retrogradation properties were analyzed after storage for 7, 14, and 40 days at 4°C; the retrogradation degree changed with the time and among the different starches, as well as the transition temperatures and enthalpies, which were lower than those observed for the gelatinization process. Other parameters like gelatinization and retrogradation temperature range ( Rgel, Rret) and PHI were analyzed. Rgel was faster for BR and slower for MT, while Rret was broader than the corresponding gelatinization and PHI was not significantly different among the studied starches, except for the BR (slightly higher value). [ABSTRACT FROM AUTHOR]

The wood is considered a natural composite of extreme complexity, mainly composed of cellulose, lignin, hemicellulose (polyposis), and extractives. Its composition encourages biological attacks from different species. In this context, several techniques have been studied and applied for disinfecting and decontaminating wood-made works of art and cultural heritage objects, which have been damaged by fungi, bacteria, and insects. Gamma radiation has been studied as an alternative to chemical methodologies for this purpose. By this way, the aim of this article is to illustrate the effect of gamma radiation on some physicochemical properties of Pinnus patula, Pinnus cunninghamia, Cedrella fissillis, and Ocotea porosa wood species. The irradiation has shown itself to be a fast and efficient process to eliminate infestations by both insects and microorganisms and no quarantine is required because of the no generation of toxic residues. On the other hand, this process does not protect the irradiated material from re-infestations or re-contamination. In this study, relatively high gamma radiation doses were applied up to 100 kGy so that radiation effects, which are cumulative, could be retrieved by means of thermal properties. The results have shown that gamma radiation, in the studied dose range, does not promote meaningful alterations on the evaluated properties, which allows that artifacts be irradiated multiple times, even if a re-infestation occurs. [ABSTRACT FROM AUTHOR]

Abstract: The main objective of this article is to investigate the influence of the thermal properties of the envelope on the thermal performance of occupied and naturally ventilated houses. A naturally ventilated house built in Southern Brazil was modelled and calibrated in the EnergyPlus computer programme. Based on this calibrated model, a reference model for computer simulations was defined, and variations in the materials of the envelope, occupation patterns and ventilation were carried out. Hourly air temperature and relative air humidity were the output data for the thermal zones of each model. By inputting such data in the Analysis Bio computer programme, the percentage of discomfort hours in the models was obtained. Correlations between the percentage of discomfort hours and the equivalent thermal transmittance, thermal capacity and thermal delay values of the components of the envelope were investigated. Such analysis made clear that there is an influence of the envelope on the thermal performance of the occupied and ventilated house, and that the number of discomfort hours is lower in the models with higher thermal capacity and thermal delay envelope values. It was also observed that thermal capacity was the thermal property with the best correlation to discomfort hours. [Copyright &y& Elsevier]

This study was undertaken over a 10-month period under environmental conditions within the state of Mato Grosso, Brazil, to evaluate the causes of variation in the technological and thermal properties of raw natural rubber (NR) from different clones of Hevea brasiliensis (GT 1, PR 255, FX 3864, and RRIM 600). These clones were chosen to represent good clones available in Brazil. The technological properties of raw NR were evaluated in terms of their dry rubber content (DRC), Wallace plasticity, plasticity retention index (PRI), and Mooney viscosity. The thermal performance was evaluated with the thermogravimetry (TG)/differential thermogravimetry (DTG) technique. There were significant variations ( p < 0.01 and p < 0.05) between clones and tappings for all technological properties, except for the percentage DRC among the clones. Of the clones studied, clone PR 255 presented the highest sensitivity to thermooxidation, as measured by its PRI value. The clone type and period of the year did not significantly influence the thermal behavior (TG/DTG under a nitrogen atmosphere) among the four clones evaluated. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Abstract: The objective of the present paper is to evaluate the thermal performance of diverse wood-based panels in small-scale test cells of 1m×1m×1m of internal volume. The thermal evaluations took place under the climatic conditions of Curitiba, Brazil (latitude 25.5°S, elevation 917m above sea level), which is characterized by a subtropical climate with high daily and annual amplitudes of the air temperature. The research comprised of the following steps: (1) heat flux measurements through each panel configuration; (2) indoor temperature measurements under summer and winter climatic conditions. Reference material for indoor temperature comparisons was a prototype made with ordinary ceramic bricks, plastered on both sides. Air temperature measurements were carried out with data-loggers, heat flux plates were attached to an exposed north facade of each test cell, while incoming solar radiation was measured with an experimental solarimeter. [Copyright &y& Elsevier]

Abstract: Values of some thermal properties and the crystalline phases of red ceramic samples from the Northern region of Rio de Janeiro state in Brazil are reported as a function of firing temperature (900, 950, 980, 1020, 1060 and 1100 °C). The open photoacoustic cell (OPC) technique and a continuous light illumination photothermal method were employed in order to obtain the thermophysical characteristics: thermal diffusivity (α) and specific heat capacity (ρc), respectively. Indirectly, using simple mathematical relations, the thermal conductivity (k) and the thermal effusivity (ε) were obtained. Crystalline phases were identified by X-ray diffraction (XRD). The intrinsic relationship between the structure and the thermal diffusivity was analysed. [Copyright &y& Elsevier]

For the purpose of evaluating the suitability of piassava fiber us reinforcement of polymer matrix (recycled polyethylene), we carried out extensive characterization of morphological, structural, thermal, and mechanical properties of two species of piassava fibers, namely Leopoldinia piassaba (Amazon, Brazil) and Attalea funifera (Bahia, Brazil). Scanning electron microscopy images revealed that each fiber is essentially a composite in which rigid cellulose microfibrils are embedded in a soft lignin and hemicellulose matrix. In addition, the tubular microfibrils are helically wound along the fiber axis forming ultimate hollow cells. An irregularly dimensioned mass, composed mainly of silica, appears on the surface of each fiber. The crystallinity of L. piassaba is found to be inferior to that of A. funifera. On the other hand, thermal analysis shows that both species start to decompose at approximately similar temperature (∼265°C), and that the moisture content in each is approximately 4 to 5%. The mechanical properties correlate well with the fiber diameter. Finally, the L. piassaba, as compared with A. funifera, is softer and more ductile. [ABSTRACT FROM AUTHOR]

The article offers news briefs as of December 2012. Scotland is planning to use renewable sources to meet half of its electricity demand by 2015. Silicon carbide (SiC) mixed signal devices have been successfully tested by Raytheon UK Ltd. at higher temperatures. One thousand and sixty aircrafts will be introduced in Brazil until 2031.