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This work investigated the functional changes in whey proteins obtained from goat milk subject to various temperature treatments. Ultra-high temperature instantaneous sterilization (UHTIS) caused less damage than the common low-temperature, whereas spray-drying treatment had the opposite effect. A total of 426 proteins were identified in UHTIS and control treatment groups, including 386 common proteins and 16 and 14 unique proteins. The UHTIS treatment upregulated 55 whey proteins while down-regulated 98. The UHTIS-treated whey proteins may upregulate three metabolic pathways but downregulate one. Overall, UHTIS only slightly impacted the composition and functions of whey proteins from goat milk compared to the common low-temperature treatments.

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Objective: The present work aimed to determine the impact of various cooking methods on sensory attributes, microbial safety, and physicochemical characteristics of ostrich meat to specify the best cooking method that guarantees the microbial safety of the meat as well as maintains nutritional values and is highly attractive to consumers. Materials and Methods: One hundred fresh leg muscles of ostriches were divided into five groups. Different cooking techniques were used for each group, as follows: roasting, boiling, grilling, frying, and microwaving. Each method was examined by evaluating the impact of various cooking methods on sensory attributes, proximate chemical analysis, protein and fat oxidation parameters, microbial load, changes in color, and the shear force of ostrich meat. Results: The oven-roasting and grilling methods are highly recommended and more appealing to consumers since they produce tenderer and juicier meat, cause less cooking loss (CL), and maintain the nutritive value of ostrich meat; however, they have the highest protein and fat oxidation rates. On the other hand, boiling and frying methods revealed good fat oxidation parameters, the highest CL, and preserved nutritional value, but unfortunately, they were not highly preferred by consumers. From a hygienic point of view, grilling and microwave cooking are the methods that ensure the microbiological safety of cooked ostrich meat, as they significantly reduce Enterobacteriaceae and psychrotrophic bacterial counts, among other cooking methods. Conclusion: The oven roasting and grilling methods were the most preferable thermal cooking techniques, as they achieved the highest acceptability to consumers and maintained the nutritive values of ostrich meat.

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PURPOSE: To evaluate the effects of 1 versus 2 glaze firings on the color and mechanical properties of an extrinsically characterized lithium disilicate ceramic after thermal cycling, brushing, or both. MATERIALS AND METHODS: Eighty specimens were divided into 2 groups: 1 glaze firing (GL1) and 2 glaze firings (GL2). Each group was subdivided into 4 groups (n = 10), according to the experimental conditions: thermal-cycling, brushing, thermal-cycling + brushing, and immersion in distilled water (control). Color variation, surface roughness, and Vickers microhardness were analyzed before each designated experiment and after the simulated periods of 2.5, 5, and 10 years. Three-way mixed ANOVA was used for all outcomes, followed by 1-way ANOVA, repeated measures 1-way ANOVA, Bonferroni post hoc test, and t-test to check for statistical differences (α = 0.05). RESULTS: Thermal cycling generated greater color changes in the GL1 group at 2.5 and 5 years (p < 0.001; p = 0.013). Brushing generated color changes in GL1 at 5 years (p = 0.003) and in GL2 at 10 years (p = 0.017). Regarding surface roughness, the GL1 group suffered alterations in thermal cycling + brushing at 5 years. In the control group, the GL1 group exhibited higher roughness values than GL2 (p < 0.05). Most of the groups experienced an increase in microhardness at 2.5 years (p < 0.05). In the GL1 group, thermal-cycling increased the microhardness at 5 years (p = 0.006); at 5 and 10 years, the GL1 group had a higher microhardness than the GL2 in thermal-cycling + brushing (p < 0.05). CONCLUSION: Ceramics with 1 glaze firing showed greater color, roughness, and microhardness changes compared to those submitted to 2 firings.

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The nucleation and growth processes of pure Fe/pure Al intermetallic compounds (IMCs) during heat treatment at 380 °C and 520 °C were observed through in situ scanning electron microscopy (SEM). The size of the IMCs were statistically analyzed using image analysis software. The types and distribution of IMCs were characterized using transmission electron microscopy (TEM) and electron backscattering diffraction (EBSD). The results showed that: at 380 °C, the primary phase of the Fe/Al composite intermetallic compounds was Fe4Al13, formed on the Fe side and habituated with Fe. The IMC was completely transformed from the initial Fe4Al13 to the most stable Fe2Al5, and the Fe2Al5 was the habitus with Fe during the process of holding at 380 °C for 15 min to 60 min. At 380 °C, the initial growth rate of the IMC was controlled by reaction, and the growth rate of the thickness and horizontal dimensions was basically the same as 0.02-0.17 µm/min. When the IMC layer thickness reached 4.5 µm, the growth rate of the thickness changed from reaction control to diffusion control and decreased to 0.007 µm/min. After heat treatment at 520 °C (≤20 min), the growth of IMC was still controlled by the reaction, the horizontal growth rate was 0.53 µm/min, the thickness growth rate was 0.23 µm/min, and the main phase of the IMC was the Fe2Al5 phase at 520 °C/20 min.

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A weldable Al-Mg-Zn-Sc alloy was produced using vacuum induction melting and an argon-protected casting method to achieve high strength and ductility, and the effects of heat treatment on the microstructure evolution and mechanical properties of Al-Mg-Zn-Sc alloys were comparatively investigated. The results reveal that fine equiaxed grains with an average grain size of 40 µm in an as-cast Al-Mg-Zn-Sc alloy change little after heat treatments, bringing about a grain-boundary strengthening of 46.1 MPa. The coarse T-Mg32(Al, Zn)49 phases at grain boundaries are completely dissolved into the matrix through solid-solution treatment, and T-Mg32(Al, Zn)49 with diameters ranging from 10 to 25 nm and Al3Sc with diameters ranging from 5 to 20 nm gradually precipitate during the artificial aging process. The Mg solid solubility is 4.67% in the as-cast Al-Mg-Zn-Sc alloy, and it increased to 5.33% after solid-solution treatment and dramatically decreased to 4.15% after post-aging treatment. The contributions of solid-solution strengthening to as-cast, post-solid-solution and post-aging Al-Mg-Zn-Sc alloys are 78.2 MPa, 85.4 MPa and 72.3 MPa, respectively. The precipitation strengthening of the post-aging alloy is 49.7 MPa, which is an increase of 21% in comparison to that of both as-cast and post-solid-solution alloys. The alloy achieves an optimal tensile strength of 355.3 MPa, yield strength of 175 MPa and elongation of 22% after undergoing solid-solution treatment.

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Heat treatment of sorghum kernels has the potential to improve their nutritional properties. The goal of this study was to assess the impact of dry heat treatment at two temperatures (121 and 140 °C) and grain fractionation, on the chemical and functional properties of red sorghum flour with three different particle sizes (small, medium, and large), for process optimization. The results showed that the treatment temperature had a positive effect on the water absorption capacity, as well as the fat, ash, moisture and carbohydrate content, whereas the opposite tendency was obtained for oil absorption capacity, swelling power, emulsion activity and protein and fiber content. Sorghum flour particle size had a positive impact on water absorption capacity, emulsion activity and protein, carbohydrate and fiber content, while oil absorption capacity, swelling power and fat, ash and moisture content were adversely affected. The optimization process showed that at the treatment temperature at 133 °C, an increase in fat, ash, fiber and carbohydrate content was experienced in the optimal fraction dimension of red sorghum grains. Moreover, the antioxidant performance showed that this fraction produced the best reducing capability when water was used as an extraction solvent. Starch digestibility revealed a 22.81% rise in resistant starch, while the thermal properties showed that gelatinization enthalpy was 1.90 times higher compared to the control sample. These findings may be helpful for researchers and the food industry in developing various functional foods or gluten-free bakery products.

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Tenebrio molitor, the first edible insect approved as a novel food in the EU, is a promising candidate for alternative protein sources, implementing circular and sustainable production systems. This study aims to determine the microbiological quality and physicochemical properties of mealworm powders obtained by four different processing pathways. Contents of dry matter, protein, fat, ash, water activity (aw) and a range of microbial counts were measured and analyzed by one-way ANOVA with Tukey's test. Results showed small differences in the proximate composition of the powder samples (protein 55.62-57.90% and fat 23.63-28.21% of dry matter, DM), except for the one that underwent a defatting step (protein 70.04% and fat 16.84%), p < 0.05. A level of water activity of less than 0.2 was reached for all pathways. Fresh mealworm samples had high total aerobic counts (8.4 log CFU/g) but were free of foodborne pathogens. Heat treatments applied during transformation were sufficient to kill vegetative cells (reduction of 2.8-5.1 log CFU/g) rather than bacterial endospores (reduction of 0.3-1.8 log CFU/g). Results were confirmed by predictive microbiology. This study validated the efficacy of a boiling step as critical control points (CCPs) of insect powder processing, providing primary data for the implementation of HACCP plans.

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OBJECTIVES: To evaluate the influence of different heat treatments and temperatures on the cyclic fatigue resistance of 2Shape instruments (Micro Mega, Besancon, France) with the same design. MATERIALS AND METHODS: A total of 80 2Shape TS1 (#25/.04) and 80 TS2 (#25/.06) files with different heat treatments (no heat-treated, NHT; C-Wire; T-Wire; CM-Wire) were tested at room (25° ± 1 °C) and body (37° ± 1 °C) temperatures in 16-mm stainless steel artificial canal with a curvature of 60° and 5 mm of radius. Files were tested in continuous rotation at 300 rpm using a customized device. Cyclic fatigue resistance was expressed in the number of cyclic to fracture (NCF). The phase transformation temperature of each file was determined by differential scanning calorimetry. Data were statistically analyzed using the two-way ANOVA and the Bonferroni post-hoc test with p < 0.05. RESULTS: All CM-Wire TS1 and TS2 files showed higher NCF than the other groups at both temperatures (p < 0.001). C-Wire TS2 showed higher resistance than NHT and T-Wire TS2 (p < 0.001), with no significant differences between the last two. Body temperature significantly decreased NCF of all tested files (p < 0.05) except for NHT and T-Wire TS1. CONCLUSIONS: Body temperature negatively affected the cyclic fatigue resistance of C-Wire and CM-Wire TS1 and of all TS2 files compared with room temperature. The CM-Wire instruments exhibited the highest cyclic fatigue resistance of all tested files. CLINICAL RELEVANCE: Heat-treated nickel-titanium files can differently perform according to environmental temperature and file dimensions. The CM-Wire 2Shape prototypes displayed the highest flexural resistance in all experimental conditions.

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Yak milk is highly nutritious in terms of abundant protein and fat, whereas little is known regarding the influence and mechanism of heat treatments on its gastric emptying and hydrolysis kinetics during digestion in the human gastrointestinal tract. In this study, a bionic human stomach-intestine system was employed to examine in vitro dynamic gastrointestinal digestion of fresh raw and heated yak milks. During gastric digestion, the formation of protein clots or aggregates was observed for all the milk samples. However, significantly more clots were found from autoclaved milk and raw milk, with a dry weight of 14.1 and 10.9 g from 200 g initial milk sample after 30 min digestion, respectively, compared to pasteurized (6.9 g) and microwaved (9.2 g) milks. For both raw and heated milks, the large-sized coalesced fat globules formed in the stomach were rapidly dissociated to small and uneven droplets upon digestion in the small intestinal conditions due to the highly efficient hydrolysis of milk fat globule membrane (MFGM) proteins and fat globules by pancreatic trypsin and lipase. Due to the formation of more dense-structured clots, a longer gastric emptying half-time was shown for the autoclaved (41.1 min) and raw (38.4 min) milks in comparison to that for the yak milks treated with microwave (34.2 min) and pasteurization (36.2 min). Consistently, the pasteurized milk (92.5 %) exhibited the highest protein digestibility at the end of digestion, followed by microwaved milk (87.8 %) ≈ autoclaved milk (86.1 %) > raw milk (80.8 %). The amount of free fatty acids (FFAs) released during digestion in general followed a similar order with that for proteolysis among the milk samples. This study highlights the crucial role of the formation of structured clots in the gastric emptying and hydrolysis of proteins and fat globules. This information will provide a mechanistic understanding of digestion kinetics of yak milk as impacted by heat treatments.

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The effect of carbon doping contents on the microstructure, hardness, and corrosion properties of heat-treated AISI steel grades of plain carbon steel was investigated in this study. Various microstructures including coarse ferrite-pearlite, fine ferrite-pearlite, martensite, and bainite were developed by different heat treatments i.e. annealing, normalizing, quenching, and austempering, respectively. The developed microstructures, micro-hardness, and corrosion properties were investigated by a light optical microscope, scanning electron microscope, electromechanical (Vickers Hardness tester), and electrochemical (Gamry Potentiostat) equipment, respectively. The highest corrosion rates were observed in bainitic microstructures (2.68-12.12 mpy), whereas the lowest were found in the fine ferritic-pearlitic microstructures (1.57-6.36 mpy). A direct correlation has been observed between carbon concentration and corrosion rate, i.e. carbon content resulted in an increase in corrosion rate (2.37 mpy for AISI 1020 to 9.67 mpy for AISI 1050 in annealed condition).

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In this research, a set of CuNiCrSiCoTi (H-0Nb), CuNiCrSiCoTiNb0.5 (H-0.5Nb) and CuNiCrSiCoTiNb1 (H-1Nb) high-entropy alloys (HEAs) were melted in a vacuum induction furnace. The effects of Nb additions on the microstructure, hardness, and wear behavior of these HEAs (compared with a CuBe commercial alloy) in the as-cast (AC) condition, and after solution (SHT) and aging (AT) heat treatments, were investigated using X-ray diffraction, optical microscopy, and electron microscopy. A ball-on-disc configuration tribometer was used to study wear behavior. XRD and SEM results showed that an increase in Nb additions and modification by heat treatment (HT) favored the formation of BCC and FCC crystal structures (CS), dendritic regions, and the precipitation of phases that promoted microstructure refinement during solidification. Increases in hardness of HEA systems were recorded after heat treatment and Nb additions. Maximum hardness values were recorded for the H-1Nb alloy with measured increases from 107.53 HRB (AC) to 112.98 HRB, and from 1104 HV to 1230 HV (aged for 60 min). However, the increase in hardness caused by Nb additions did not contribute to wear resistance response. This can be attributed to a high distribution of precipitated phases rich in high-hardness NiSiTi and CrSi. Finally, the H-0Nb alloy exhibited the best wear resistance behavior in the aged condition of 30 min, with a material loss of 0.92 mm3.

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The artificial aging heat treatments performed directly on as-built and solubilized AlSi7Mg0.6 and AlSi10Mg0.3 samples were characterized and discussed. The analysed bars and billets (height of 300 mm) were manufactured via the Laser Powder-Bed Fusion process on a build platform heated at 150 °C. Therefore, its influence on the as-built samples was studied in terms of mechanical performance variations between the bottom and top regions. Vickers microhardness measurements were performed to obtain aging profiles after direct aging (175-225 °C) and T6 heat treatments and to highlight better time and temperature parameters to optimize the mechanical properties of both alloys. SEM observations were used to characterize the microstructure before and after the heat treatments and its influence on the fracture mechanisms. Generally, the direct aging heat treatments show the same effects on both aluminium alloys, unlike the solubilization at 505 °C followed by artificial aging at 175 °C. The strengths vs. elongation values obtained after the direct aging treatments are better than those exhibited by T6 as highlighted by the quality index.

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The aim of this study was to explain the mechanical differences between EdgeTaper Platinum (ETP) and ProTaper Gold (PTG) determining the transition temperatures and the composition of the alloy of ETP, since no data are present in literature. A total of 130 instruments were selected: 65 ETP F2 and 65 PTG F2. 20 instruments per type were submitted to each mechanical tests. The cyclic fatigue and torsional tests were performed at a pre-set temperature of 35 °C ± 1 °C. During the cyclic fatigue test, Time to fracture, number of cycles to fracture (NCF) and the fragment length (FL) were recorded. During the static torsional, Torque to Fracture (TtF) and FL were recorded. The fracture surface of 5 randomly selected fragments from each test was examined through a Scanning Electron Microscopy (SEM) and an EDX analysis was performed. 20 instruments per type were submitted to a bending test The force generated (grams) to bend each was recorded. Recorded data of mechanical and metallurgical tests were statistically analyzed using a one-way analysis of variance (ANOVA) test with significance set to a 95% confidence level. ETP F2 showed a higher cyclic fatigue resistance and bending ability than PTG F2, with a statistically significant difference (p < 0.05). PTG showed a higher torsional resistance with a statistically significant difference (p < 0.05). DSC analysis of 5 samples for each instrument type pointed out that the austenite finish temperature of PTG was higher than the ETP, respectively of 49.99 ± 3.31 (°C) and 38.92 ± 1.75 (°C). EDX analysis confirmed the near-equiatomic composition of the Ni-Ti alloys, with a presence of a third component recognized as rubidium in the ETP samples. ETP showed higher flexibility in comparison with PTG, despite the latter is characterized by a more martensitic characterization. since its Af temperature is higher than the ETP.

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This work focuses on the effect of different heat treatments on the Ti-6Al-4V alloy processed by means of electron beam melting (EBM). Super ß-transus annealing was conducted at 1050 °C for 1 h on Ti-6Al-4V samples, considering two different cooling paths (furnace cooling and water quenching). This heat treatment induces microstructural recrystallization, thus reducing the anisotropy generated by the EBM process (columnar prior-ß grains). Subsequently, the annealed furnace-cooled and water-quenched samples were aged at 540 °C for 4 h. The results showed the influence of the aging treatment on the microstructure and the mechanical properties of the annealed EBM-produced Ti-6Al-4V. A comparison with the traditional processed heat-treated material was also conducted. In the furnace-cooled specimens consisting of lamellar α+ß, the aging treatment improved ductility and strength by inducing microstructural thickening of the α laths and reducing the ß fraction. The effect of the aging treatment was also more marked in the water-quenched samples, characterized by high tensile strengths but limited ductility due to the presence of martensite. In fact, the aging treatment was effective in the recovery of the ductility loss, maintaining high tensile strength properties due to the variation in the relative number of α/α' interfaces resulting from α' decomposition. This study, therefore, offers an in-depth investigation of the potential beneficial effects of the aging treatment on the microstructure and mechanical properties of the EBM-processed super ß-transus heat-treated Ti-6Al-4V alloy under different cooling conditions.

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Nowadays, to improve quality of life, to have a more comfortable life, in internal spaces we try to maintain conditions that are free from external environmental influences. Thus, existing as well as newly built houses have adequate interiors maintaining their temperature, warming, or cooling due to the environment compensation. One way to create this is to reduce the heat loss in buildings. An option to achieve this is the application of thermal insulations. Nowadays, the use of super insulation materials such as aerogel and vacuum insulation panels and other nano-structured insulations, such as graphite doped expanded polystyrene, is becoming increasingly justified. These are relatively new materials, and we know only a little about them. This paper presents research results based on temperature-induced investigations of nanostructured graphite expanded polystyrene, to reveal its thermal stability after long-term and short-term thermal annealing, simulating the ageing of the material. Firstly, with a differential scanning calorimeter, we will explore the thermal stability profile of the specimens. After this, the paper will present temperature-induced changes in both the thermal properties and the structure of the samples. We will also present changes in the thermal conductivity, modifications in the surface, and compressive property variation induced by thermal annealing. The samples were thermal annealed at 70 °C for 6 weeks, at 100 and 110 °C for 1 h. Besides the thermal conductivity measurements with Netzsch 446 heat flow meter equipment, we will present specific heat capacity measurement results executed with the same equipment. Moreover, sorption isotherms of the as-received and annealed samples were registered and completed with hydrophobic experiments, too. Furthermore, from the measurements, we showed that temperature should affect a significant change in the thermal conductivity of materials. Moreover, the changes in the graphite expanded polystyrene before and after thermal annealing were investigated by Scanning Electron Microscopy, as well as optical microscopy. The structural changes were further followed by an X-ray diffractometer and the IR absorption capability was tested, too.

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Laser powder bed fusion (L-PBF) is an additive manufacturing technology that is gaining increasing interest in aerospace, automotive and biomedical applications due to the possibility of processing lightweight alloys such as AlSi10Mg and Ti6Al4V. Both these alloys have microstructures and mechanical properties that are strictly related to the type of heat treatment applied after the L-PBF process. The present review aimed to summarize the state of the art in terms of the microstructural morphology and consequent mechanical performance of these materials after different heat treatments. While optimization of the post-process heat treatment is key to obtaining excellent mechanical properties, the first requirement is to manufacture high quality and fully dense samples. Therefore, effects induced by the L-PBF process parameters and build platform temperatures were also summarized. In addition, effects induced by stress relief, annealing, solution, artificial and direct aging, hot isostatic pressing, and mixed heat treatments were reviewed for AlSi10Mg and Ti6AlV samples, highlighting variations in microstructure and corrosion resistance and consequent fracture mechanisms.

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In this study, the effect of heating temperature on the structure of graphenic-based carbon (GC) has been successfully investigated. A series of GC materials was prepared from coconut shells by a green synthesis method. The process includes heating at four temperatures (T = 400, 600, 800 and 1000 °C) followed by an exfoliation process assisted by hydrochloric acid (HCl). These materials were characterized by wide- and small-angle x-ray scattering (WAXS and SAXS), Fourier-transform infrared spectroscopy (FTIR), x-ray photoemission spectroscopy (XPS) and transmission electron microscopy (TEM). The WAXS analysis shows Braggs peaks corresponding to the reduced graphene oxide (rGO)-like phase. Investigations by FTIR and XPS methods show the presence of carbon-oxygen functional groups such as C=C (carbon with sp 2 hybridization), C-C (carbon with sp 3 hybridization), and C=O bonds. The sp 2 bonds form a 2-dimensional (2D) network in hexagonal lattice, while carbon with sp 3 bonds tends to form a 3-dimensional (3D) tetrahedral structure. The BET analysis revealed meso- and micro-pore structures in GC. Heating process reduces the specific surface area and increases pore size of GC. Moreover, increasing the heating temperature induces a decrease in radius of gyration (R g) and an increase in the formation of 2D structures in GC. The fitting results of SAXS profiles, proved by TEM and XPS, yielded the structure of GC containing the mixture of 2D and 3D structures. Thus, it is suggested that the GC has a mesostructure.

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Furan formations were monitored in commercially refined sunflower, soybean and olive oils during heat treatments at 170, 180 and 190 °C for 0, 2, 4, 6 and 8 h. The lowest furan concentrations were detected in sunflower oil at all temperatures, while soybean oil generated the highest furan concentration at 190 °C at the end of 8th hour. Furan contents were higher in olive oil at 170 and 180 °C, which might be due to its high diglyceride content. Furan formation linearly increased with time. Zero-order kinetic equations were used to determine kinetic parameters. Temperature was found effective on the furan formation because increases in reaction rate constants were observed by increasing the temperature. Using Arrhenius equation, activation energies of sunflower, soybean and olive oils were calculated as 45.08, 100.24 and 22.41 J/mol, respectively.

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Astroloy is a Ni-based superalloy with high-volume fraction of γ', which gives high temperature properties but reduces its forgeability. Therefore, powder metallurgy manufacturing processes such as Near Net Shape HIPping are the most suitable manufacturing technology for Astroloy. However, NNSHIP has its own drawbacks, such as the formation of prior particle boundaries (PPBs), which usually tend to decrease material mechanical properties. The detrimental effect of PPBs can be reduced by optimizing the entire HIP processing route. Conventional HIP cycles have very low cooling rates, especially in big components from industry, and thus a series of post-heat treatments must be applied in order to achieve desirable microstructures and improve the mechanical properties. Standard heat treatments for Astroloy are long and tedious with several steps of solutioning, stabilization and precipitation. In this work, two main studies have been performed. First, the effect of the cooling rate after the solutioning treatment, which is driven by the materials' thermal mass, on the Astroloy microstructure and mechanical properties was studied. Experimental analyses and simulation techniques have been used in the present work and it has been found that higher cooling rates after solutioning increase the density of tertiary γ' precipitates by 85%, and their size decreases by 22%, which leads to an increase in hardness from 356 to 372 HB30. This hardness difference tends to reduce after subsequent standard heat treatment (HT) that homogenizes the microstructure. The second study shows the effect of different heat treatments on the microstructure and hardness of samples with two different thermal masses (can and cube). More than double the density of γ' precipitates was found in small cubes in comparison with cans with a higher thermal mass. Therefore, the hardness in cubes is between 4 and 20 HB 30 higher than in large cans, depending on the applied HT.

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BACKGROUND: Heat can be effective for bed bug elimination. However, in some cases bed bugs survive heat treatments. The objectives of this study were to determine the behavioral responses of bed bugs to rising harborage temperatures (23.0-49.0 °C) and identify which heat shock protein (HSP) genes are expressed after heat exposure. First, a custom-made copper arena and harborage were used to determine the escape behaviors of six bed bug populations. Next, HSP gene expression responses of select populations were determined after heat exposure using real time quantitative polymerase chain reaction (RT-qPCR). RESULTS: Analysis of the 25 min behavioral experiment data found that harborage top temperatures associated with 25%, 50% and 75% probabilities of bed bugs to flee the harborage did not differ significantly between populations. Also, the percentage of insects that escaped from heated areas and survived (4.0-12.0%) was not different between populations. However, when specific temperatures at which successful escapes occurred were statistically compared, the Poultry House population was found to flee the harborage at statistically higher temperatures (43.6 ± 0.5 °C) than others (40.5 ± 0.6-42.0 ± 0.7 °C). The RT-qPCR experiments revealed that the HSP70.1, HSP70.3, and Putative Small HSP genes were significantly up-regulated 15 min, 2, and 4 h post-heat exposure and decreased back to baseline levels by 24 h. CONCLUSIONS: This study shows that when harborage top temperatures approach 40.0-43.0 °C, bed bugs will disperse in search for cooler areas. This work implicates the HSP70.1, HSP70.3, and Putative Small HSP genes in heat induced stress recovery of bed bugs. © 2021 Society of Chemical Industry.

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