Temperate Periods Research Articles

Review of Annemarie McAllister, Writing for Social Change in Temperance Periodicals: Conviction and Career

Review of Annemarie McAllister, Writing for Social Change in Temperance Periodicals: Conviction and Career

Microstructure evolution of V-containing low carbon ultra-fine bainitic steel during medium-temperature tempering and strengthening-toughening mechanism

In the present study, the microstructure evolution and the corresponding mechanical properties of V-containing low carbon ultra-fine bainitic steel during tempering were studied. The results show that during the initial stages of tempering, part of retained austenite in V-containing ultra-fine bainite steel transforms into bainite. The stability of the retained austenite improves when the tempering period is increased to 5 h. Simultaneously, nano-sized VC precipitates are precipitated in the microstructure. On the one hand, these phases can give full play to the transformation-induced plasticity (TRIP) effect by modulating the carbon content of the retained austenite. On the other hand, they can also reduce the lattice distortion in the matrix and combine it with the lower dislocation density, thereby improving the plasticity of the specimen. At the same time, the fine precipitated phase can also effectively improve the toughness of the cleavage crack region in the transition zone, preventing the micro-cracks from generating at the interface of the precipitated phase and then extending to the adjacent matrix to cause fracture, so that the uniform elongation, total elongation, impact toughness at room temperature and impact toughness at low temperature of the 5 h specimen are as high as 8.8 ± 0.2 %、16.2 ± 0.7 %、113 ± 4 J/cm2 and 76 ± 2 J/cm2, respectively. Furthermore, the primary contribution of the strengthening mechanism in the microstructure has shifted from fine grain strengthening and dislocation strengthening to precipitation strengthening, and part of the retained austenite undergoes a martensitic transformation during cooling, resulting in the highest yield strength of 1086 MPa for the 5 h specimen. The tensile strength is effectively maintained at 1402 MPa by increasing the tempering period, which has good tempering resistance, to achieve the comprehensive performance optimization of bainitic steel.

Effect of Infrared-Combined Hot Air Intermittent Drying of Jujube (Zizyphus jujuba Miller) Slices: Drying Characteristics, Quality, and Energy Consumption Dimensions

The objective of this research was to investigate the effect of infrared-combined hot air intermittent drying (IIRHAD) on energy consumption, drying characteristics, and the quality of jujube slices. The water content of jujube slices decreased from 0.267 g/g to 0.05 g/g during the experiment, and the infrared heating plate’s temperature was fixed at 70 °C while the hot air temperature was fixed at 50 °C. Nine different intermittent ratios were used to dry jujube slices, and the results showed that intermittent treatment had varying effects on drying characteristics, energy consumption, and quality. In comparison to infrared-combined hot air drying (IRHAD), the effective drying time of red jujube slices was reduced by 40 to 100 min, the energy consumption decreased by 11.91% to 34.34%, and there were also varying degrees of improvement in the quality indicators. It was discovered that excessively long or short active drying and tempering periods had a negative impact on the drying process. Therefore, these factors should be further broken down and improved in the future. This research holds great importance for the future advancement and widespread use of IIRHAD in fruit and vegetable materials.

Assessment of continuous and intermittent drying on antixidant activity of corn grains

Grain drying is essential for storage to preserve material quality. However, drying can affect the composition of agricultural material, as exposure to high temperatures for long periods can reduce the quality of the grain, in terms of antioxidant activity and germination power. The objective of this work was to assess the continuous and intermittent drying, in order to maximize the preservation of corn grains antioxidant potential. Experiments were conducted at 40, 55, and 70 °C with tempering periods of 5 and 10 minutes. Solvents used were methanol/water 70/30 (v/v), methanol/water 95/5 (v/v), ethanol/water 70/30 (v/v), and ethanol/water 95/5 (v/v) and extraction times of 1, 4, and 24 hours. Antioxidant activity analysis was carried by DPPH and ABTS radicals scavenging and the best results of antioxidant activity for in natura grains were obtained with methanol/water 70/30 (v/v) and 4 h. Intermittent drying of 5 and 10 minutes’ periods at 40 °C led to least reduction of antioxidant activity percentage compared to in natura corn results. This study demonstrated that intermittent drying conducted at low temperatures is an effective alternative to preserve bioactive compounds of corn.

Writing for Social Change in Temperance Periodicals: Conviction and Career by Annemarie McAllister (review)

Writing for Social Change in Temperance Periodicals: Conviction and Career by Annemarie McAllister (review)

Study on dislocation density, microstructure, and mechanical properties of P92 steel for different heat treatment conditions

AbstractThe impact of various heat treatment procedures on microstructure, dislocation density, hardness, tensile characteristics, and impact toughness of P92 steel was examined in the current experiment. The martensitic microstructure and average microhardness of 463 HV 0.2±8 HV 0.2 of the normalized steel were prevalent. A tempering procedure was carried out at 760 °C for a range of 2 hours to 6 hours. Additionally, an X‐ray diffraction examination was carried out, and the results were used to determine the dislocation density. The normalized sample was characterized by a high dislocation density. The dislocation density was decreased by tempering of normalized samples. With an increase in tempering time, the effect of the treatment coarsened the grains, precipitates, and decreased the area fraction of precipitates. After tempering, MX, M23C6, and M7C3 types precipitates were found to have precipitated, according to energy dispersive spectroscopy and x‐ray diffraction research. The ideal tempering period was determined to be 4 hours at a tempering temperature of 760 °C based on the microstructure and mechanical characteristics. Steel that was tempered at 760 °C for 4 hours had a yield strength of 472 MPa, an ultimate tensile strength of 668.02 MPa, and an elongation of 26.05 %, respectively.

Tempering time and air temperature relationships for real-scale paddy drying and their effects on the physical, physicochemical, and morphological qualities of polished rice

Tempering-drying time may affect the quality of polished rice. Hence, this study aims to evaluate the effect of drying-tempering time and air temperature relationships on the physical, physicochemical, and morphological qualities of polished rice. Herein, paddy with 20–24% (w.b.) moisture were subjected to drying and tempering with air temperatures of 75–115 °C, 115–130 °C, and 75–130 °C over 14 h to reduce their moisture content up to 12% (w.b.). With the increase in the paddy mass temperature to 49 °C, the whole grain yield and the percentages of protein, crude fiber, fat, and ash reduced; additionally, the morphology of starch and the composition of minerals were altered. The cumulative effects and prolonged time of the drying-tempering influenced the physical, physicochemical, and morphological qualities of the rice. In conclusion, paddy drying technologies with tempering periods should not be designed for temperatures not exceeding 75 °C and drying times not longer than 8 h for good system performance and rice quality.

Parsing prehistoric patterns: Prospects and limitations of a big radiocarbon dataset for understanding the impact of climate on Late Palaeolithic and Mesolithic populations in northwest Europe (16–7.5 ka calBP)

Hunter-gatherer populations in northwest Europe were variably affected by Late Glacial and Early Holocene climate fluctuations and their effects on sea level and the environment. We investigate the impact of these fluctuations with a dates-as-data approach to a large radiocarbon dataset. Radiocarbon dates are used as a proxy for past human activity, the intensity, nature and archaeological visibility of which will indirectly influence date density. The significance of changes is explored using Kernel Density Estimates and model tested Summed Probability Distributions. Whereas previous studies have focused on smaller highly curated datasets to minimise research and preservation biases, our more inclusive approach maximises sample size, which is essential for these methods to reliably reflect underlying patterns. To deal with biases, we test subsets of the dataset that are potentially affected by differences in formation processes.The summed radiocarbon dataset follows the general fluctuations of climate conditions, showing increased activity in temperate periods and decreased activity during cold phases. Our results indicate significant periods of interest where the data deviates positively or negatively from our models. Notably we observe the impact of the Younger Dryas, Preboreal Oscillation and the 8.2 ka event on the density of hunter-gatherer activity. Additionally we see peaks in activity in our dataset during the Early and Late Boreal. Permutation testing of different regions in the research area shows these patterns are geographically differentiated.Our exploration of biasing factors indicates that we should be careful to interpret the abovementioned patterns, as different sampling processes and national policies may lie at the basis of several patterns. Furthermore, calibration artefacts may also cause issues at key parts of the timeline. Dates-as-data approaches require an understanding of the archaeology, the timing of external events, the impact of the calibration curve and how biases inherent to the dataset and research area may have influenced the formation of patterns in the result.

On the Choice of the Most Suitable Period to Map Hill Lakes via Spectral Separability and Object-Based Image Analyses

Technological advances in Earth observation made images characterized by high spatial and temporal resolutions available, nevertheless bringing with them the radiometric heterogeneity of small geographical entities, often also changing in time. Among small geographical entities, hill lakes exhibit a widespread distribution, and their census is sometimes partial or shows unreliable data. High resolution and heterogeneity have boosted the development of geographic object-based image analysis algorithms. This research analyzes which is the most suitable period for acquiring satellite images to identify and delimitate hill lakes. This is achieved by analyzing the spectral separability of the surface reflectance of hill lakes from surrounding bare or vegetated soils and by implementing a semiautomatic procedure to enhance the segmentation phase of a GEOBIA algorithm. The proposed procedure was applied to high spatial resolution satellite images acquired in two different climate periods (arid and temperate), corresponding to dry and vegetative seasons. The segmentation parameters were tuned by minimizing an under- and oversegmentation metric on surfaces and perimeters of hill lakes selected as the reference. The separability of hill lakes from their surrounding was evaluated using Euclidean and divergence metrics both in the arid and temperate periods. The classification accuracy was evaluated by calculating the error matrix and normalized error matrix. Classes’ reflectances in the image acquired in the arid period show the highest average separability (3–4 higher than in the temperate one). The segmentation based on the reference areas performs more than that based on the reference perimeters (metric ≈ 20% lower). Both separability metrics and classification accuracies indicate that images acquired in the arid period are more suitable than temperate ones to map hill lakes.

A Middle Pleistocene Butchery Site at Great Yeldham, Essex, UK: Identifying Butchery Strategies and Implications for Mammalian Faunal History

This paper discusses the evidence relating to an assemblage of Pleistocene bones and teeth discovered in a brick pit at Great Yeldham, Essex, in the late nineteenth century. Surviving elements from this collection, which include a bison foot bone with cut-marks, are now in the British Geological Survey Museum, Keyworth. A re-examination of this collection suggests that humans were present at the site during a temperate period in the earlier part of the late Middle Pleistocene. The cut-marks suggest that the hind foot was detached and discarded as butchery waste at the death site. Finally, the paper discusses the implications of humanly modified bones for understanding aspects of early human behaviour and distribution in Britain, which have hitherto largely centred around the study of stone tools.

A New Empirical Model for Predicting Intermittent and Continuous Drying of “Neve” Melon (Cucumis melo sp.) Seeds

The objective of this work was to intermittently and continuously dry “Neve” melon seeds and study their behavior. The seeds were dried in a fixed-bed dryer at a temperature of 60 °C under the influence of air velocity of 1 m s−1, followed by the prediction of drying kinetics, including that of intermittent processes with its effective time (pseudo-continuous drying) and tempering time (intermittent drying). The dried seeds were crushed to produce flour. The flours were evaluated for physicochemical parameters. To describe drying kinetics (continuous and intermittent drying) of “Neve” melon seeds, empirical models were used, including a new model proposed in this article to describe intermittent drying when the period of intermittence is included in the process. An optimization software was developed (LS Optimizer) and used to determine parameters (and their uncertainties) of the intermittent drying. The parameters of empirical models, used to describe continuous and pseudo-continuous drying, were determined by LAB Fit Curve Fitting Software. The Page model was the one that best fitted in the prediction of the experimental data of continuous and pseudo-continuous drying kinetics of seeds. A new model proposed in this work, based on Page and Lewis equations, was able to predict the kinetics of intermittent drying processes including the tempering time. The flours showed moisture content below 6%, and intermittent drying preserved proteins and lipids more than continuous drying, especially with drying and tempering periods of 10 and 20 min, respectively.

Late-Glacial palaeotemperatures and palaeoprecipitations in the Aubrac Mountains (French Massif Central) reconstructed from multiproxy analyses (Coleoptera, chironomids and pollen)

New investigations performed with a multi-proxy approach provide a robust climate reconstruction for the Late-Glacial in the Massif Central, France. The temperature reconstruction from Coleoptera is obtained from the Mutual Climatic Range Method, or “MCR” method, based on the range of climates corresponding to the area occupied today by the species identified in fossil assemblages. The Weighthed Averaging Partial Least Squared (WA-PLS) method is used to produce mean July temperature estimates from Chironomid assemblages. Climate reconstruction from pollen data is performed using an assemblage approach, the Modern Analogue Technique. During the Late-Glacial the July temperature (Tmax) reconstructed from beetles (Coleoptera) was lower than the current Tmax of 18.9 °C. Summer conditions were close to the present at the beginning of the Oldest Dryas (17400–14600 cal. BP), and during most of the Allerød (13900–12800 cal. BP). During the Younger Dryas (12800–11700 cal. BP) Tmax estimates ranged from 12 to 13 °C, much lower than today. The Tmax increased at the onset of the Holocene (11700 cal. BP), reaching values close to the modern conditions from the beginning of the period. Tmax reconstructed from chironomids shows an initial warming around 15000 cal. BP, with a Tmax rise from 7 °C to 11 °C. A maximum (13.5 °C) was reached around 13800 cal. BP. A second optimum of 16 °C occurred after 10800 cal. BP. The Late-Glacial Interstadial (LGI) is marked by temperature decreases (from 13 to 12 to 10–9 °C) around 13200–12900 cal. BP. A second climate minimum was reached around 12600 cal. BP, during the Younger Dryas (Tmax about 10 °C). The end of the Younger Dryas seems to have been warmer, with a Tmax of about 13 °C, just before the early Holocene climate improvement. Pollen-inferred results showed that the Late-Glacial climate at Roustières was characterized by colder and drier winter and summer seasons than today, and by conditions close to the modern ones around 11700 cal. BP, at the onset of the Holocene. Climate conditions comparable to the modern ones were also evidenced at the end of the Allerød, with colder than today conditions evidenced from both Tmax and Tmin (January temperature). During the Oldest and Younger Dryas the coldest month showed a temperature of −13 °C, while summers appeared more moderate (warmest month around 16 °C). Cold conditions were also reconstructed during the Bølling, while temperatures comparable to present-day values were reached during the Allerød. A cold oscillation occurred around 13400 cal. BP. Particularly dry conditions were reconstructed during the Oldest Dryas (17000–15800 cal. BP). From 15800 to the end of the Younger Dryas, the precipitation oscillated around 750 mm, but increased during the Allerød and the Holocene periods. These climatic trends reconstructed by the three proxies allowed identifying the temperate periods (LGI and the Holocene) and the cold events (Younger Dryas) of the Late-Glacial period. However, difficulties due to different sampling resolutions emerged, and several discrepancies linked to the proxy or the methods used are discussed.

Reappraisal of the chronology of Orgnac 3 Lower-to-Middle Paleolithic site (Ardèche, France), a regional key sequence for the Middle Pleistocene of southern France

Previous studies have suggested that the Lower-to-Middle Paleolithic transition was associated with the earliest Neanderthals, but recent research has established that the oldest Neanderthal fossils and the first signs of their technologies and behavior appear from MIS 11 or possibly earlier. To understand these changes, re-evaluation of the evidence is necessary to determine if this transition corresponds to a progressive evolution rather than abrupt change. Orgnac 3 is a key and appropriate site to study this research context. Located in southern France, it yields a long stratigraphic sequence testifying the evolution of technical and subsistence behaviors of pre-Neanderthal human groups during a Middle Pleistocene interglacial-glacial cycle. In this article, a new chronological framework is provided for the sequence based on results of dating methods applied to various types of geological materials. Speleothems and volcanic minerals, dated in previous studies by U-series and 40Ar/39Ar, respectively, show periods of calcitic crystallization and regional volcanic activity. Other materials, such as heated flints and herbivore teeth, are directly related to evidence of anthropogenic activities and are analyzed in the present work by trapped-charge dating methods such as thermoluminescence and electron spin resonance combined with uranium series (ESR/U-series). The new thermoluminescence and ESR/U-series dates confirm the attribution of the Orgnac 3 stratigraphic sequence to the MIS 10–MIS 8 period and are discussed in relation to paleoenvironmental data derived from bioarchaeological studies. The paleoanthropological levels, including the emergence of Levallois technology, are dated to ca. 275 ka (early MIS 8) and appear coeval to a wet and temperate period recorded locally, the Amargiers interstadial, defined in the regional palynological records. The implications of this reassessed chronology for the archaeological assemblages are discussed in the wider context of behavioral innovations from MIS 11 onward and their establishment in subsequent periods.

Comprehensive analysis of intermittent drying. A theoretical approach

Intermittent drying is a promising technique that may improve drying performance, when compared to stationary drying. An intermittent drying is composed of a succession of cycles, each of them consisting in an active drying period followed by a tempering period. It is typically characterized by two parameters: the duration of the cycles tc and the ratio of the duration of the drying period of a cycle to the total duration of the cycle χ. In this work, we derive two general models of the intermittent drying of a solid material, corresponding to different physical situations: a continuous model, to describe a situation where liquid water is continuously distributed through the material, and a shrinking core model, to describe a situation where the material is divided into a humid core and a dry zone. With these models, we provide a thorough analysis of the influence of the parameters characterizing the intermittent drying of a material on the dynamics of this drying, over wide ranges of values of these parameters. The results allows the identification of three possible regimes in the dynamics of an intermittent drying, when it is compared to a stationary one, what is summarized into an operational diagram that could be useful to select the best parameters for an intermittent drying process. Notably, the results show that one of these regions (with small values of tc and χ) corresponds to high energy efficiency, without significantly increasing the total drying time compared to continuous drying, if the external resistance to mass transfer is negligible. The models also exhibit that the external mass transfer Biot number, Bim, has a strong influence on the dynamics of an intermittent drying; the influence of tc and χ on drying performance is mitigated as Bim decreases. Finally, the models are used to shed new light on experimental data from the literature, regarding the intermittent drying of several products, for different operating conditions. The investigation of the influence of the operating conditions and the product properties on the drying performance shows that strategies such as varying the intermittency ratio or using inherently intermittent dryer can enhance the drying kinetics.

Office user work performance indicator in warm temperate summer period

The purpose of this work was to develop a methodological tool to evaluate office space work performance during the summer period. The proposed tool is an optimal work performance indicator called IRLO, which combines environmental variables on thermal, air quality, visual and acoustic influence. Integrated measurements were run for its development alongside surveys to users-workers of an office building in the city of San Juan - Argentina. The results reveal the preference ranges of each variable, recognizing that in open plan offices, there is a greater environmental adaptive capacity than in closed plan offices. It is concluded, that the indicator stands out by providing a basis to identify work performance considering environmental variables that should, in the future, be considered in the design phase.

Intermittent drying of Lippia origanoides H.B.K. leaves and Schinus terebinthifolius Raddi fruits

Drying is an indispensable process for maintaining the quality of medicinal plants after harvest. However, the continuous exposure to heated air during drying can induce physical and physicochemical alteration, besides volatile compounds in the dry plant material. Intermittence has the advantage of reducing the exposure time to heat, introducing tempering periods to drying, minimizing losses due to the process. In this context, the objective of this study was to evaluate the influence of the application of different intermittence ratios on the yield and quality of the essential oil of Lippia origanoides Humboldt, Bonpland, and Kunth (H.B.K.) leaves and of Schinus terebinthifolius Raddi fruits and on the color of Lippia origanoides leaves. The leaves and fruits were subjected to 4 drying procedures: drying without intermittence (continuous drying) and drying with tempering period (10:20; 15:15; 20:10), where the numbers indicate the duration of each interval (drying:tempering), in minutes. The drying air temperatures were 50, 60, and 70 °C and the air flows were 1 m s−1 for the leaves and 2 m s−1 for the fruits. The essential oils of both species were extracted by hydrodistillation and their constituents were identified and quantified by gas chromatography coupled to mass spectrometry (GC–MS). The color of Lippia origanoides leaves was determined by direct reflectance reading of the coordinates L*, a*, and b*, on the adaxial face of the leaves before and after drying. Drying with the 10:20 intermittence ratio at 70 °C provided the highest yields and the best quality of the essential oil of Lippia origanoides dried leaves, preserving Thymol and not resulting in degradation of color attributes. For Schinus terebinthifolius fruits, drying with a 10:20 intermittence ratio at 50 °C maximized essential oil yield and resulted in a higher concentration of the compound α-Phellandrene.

Characterization of moisture transfer during intermittent drying process for broccoli from LF-NMR experiments

Intermittent drying is considered as one of the alternative drying methods to save energy and improve product quality. In this study, low-field nuclear magnetic resonance (LF-NMR) has been used to evaluate the dynamics of the water mobility and distribution during the intermittent drying process. The results have shown that the first drying period of 1 hour is not effective to induce the moisture self-diffusion in the tempering period. After drying of 2 hours, the moisture transport in the tempering period became rapid and the changes reflected on T2 curve became visible clearly. The T2 values decreased gradually during drying, which indicated the reduced water mobility. As the tempering period progresses, the T2 continuously reduced and varied, which indicated the redistribution of water molecules during the tempering period. With the prolonged tempering time, the changes in T2 tended to be more stable, but it cannot reach equilibrium when there was concentration gradient. It was worth noting that A21 and A22 had an opposite trend during the intermittent drying process, indicating that the mobility of the bound water was increased during the intermittent drying. Effectively also when the samples were dried with the intermittent drying strategies, the vitamin C retention has increased by almost 50% relative to that of the continuous mode.

Influence of infrared heating on the functional properties of processed lentil flours: A study focusing on tempering period and seed size

Lentils are an important member of the nutritious Leguminous crops, and the functional properties of lentil flours can be effectively improved by infrared heating, an efficient and short-time thermal processing method. This research primarily focused on the effects of tempering time (24–96 h) and seed size on the modification of lentils using infrared heating. Lentil seeds of three varieties, including CDC Greenstar (large green), CDC Imvincible (small green), and CDC Maxim (small red), were tempered at 25% moisture for 24, 48 and 96 h and then infrared heated to a surface temperature of 130 and 150 °C. Overall, under the same infrared heating treatment, a longer tempering period and a smaller seed size led to greater degrees of starch gelatinization and protein denaturation. In addition, a smaller seed size and a higher surface temperature tended to cause a higher level of photodegradation of amylose (possibly amylopectin too). Due to these physicochemical changes, the combined treatment of tempering and infrared heating noticeably reduced the average particle sizes, enhanced the water-holding capacity, diminished the peak and final viscosities, and decreased the gel hardness of the processed lentil flours. Generally, more obvious effects were found with higher levels of starch gelatinization, protein denaturation, and breakdown of amylose. The present study advanced our understanding of how extended tempering and seed size influenced the techno-functional properties of lentil flours modified using infrared heating. The new findings from the research are meaningful for the utilization of infrared heating to process lentil seeds for the development of novel food ingredients.

Energy-saving new drying technology: Interval starting accessibility drying (ISAD) used to intensify dehydrofreezing efficiency

The aim of this study is to develop a new emerging technique to solve the main problem of conventional drying which is energy consumption. Interval Starting Accessibility Drying (ISAD) is based on subjecting food samples to an instantaneous action of hot air close to the starting accessibility time, during very short time followed by tempering periods (< 5 min). Quince samples have been submitted to ISAD with a temperature of 40 °C and different air flow velocities (2; 3.5; and 5 m/s), with 15 s of active time and tempering periods between 1 and 5 min. The impact of ISAD compared to conventional drying has been significant in terms of effective drying time and energy consumption. Hence, ISAD treatment significantly reduces the effective drying time by about 89% to reach the same final water content for conventionally dried quince samples. These results have promoting technological impact: a significant gain of energy is gotten by inserting short tempering periods. Consequently, ISAD can be considered as a relevant way for intensifying the internal resistance to water transfer during pre-drying process of fruits.

Intermittent Drying of Rice Grains with Husk: Modelling and Experimentation

This chapter presents an analytical modeling of mass transfer in wet porous bodies during the continuous and intermittent drying process in fixed bed. The drying process was simulated assuming the liquid diffusion as the only mass transport mechanism and constant mass diffusion coefficient. The presented models involve spherical, cylindrical and prolatespheroidalgeometries. Simulation tests of intermittent drying of ellipsoidal solids were performed and the results were compared with the continuous drying curve in order to evaluate the tempering effect in the drying process optimization. It was possible to simulate the moisture distribution during the tempering period. As an application, the methodology is used to describe intermittent drying of rough rice (BRSMG Conai variety) at temperature of 40°C and tempering periods from 0 to 1 hour. Experimental data were used to estimate the diffusion coefficient. Under the considered operating conditions, it was verified that intermittent drying provides reduction in effective operating time when compared to continuous drying.