Journal articles: 'Maximum temperature difference'

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Драбкин, И. А. "Холодильный коэффициент составной охлаждающей термоэлектрической ветви". Физика и техника полупроводников 53, № 5 (2019): 685. http://dx.doi.org/10.21883/ftp.2019.05.47563.21.

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AbstractOne of the main energy characteristics of a cooling leg is the maximum available temperature difference (Δ T _max). Its increase indicates an increase in the coefficient of performance (COP) at all temperatures. The use of a segmented leg makes it possible to increase the Δ T _max value; however, the maximum available COP increases only at large temperature differences, whereas at small temperature differences the maximum available COP is even smaller than in a simple leg.

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Vikhor, L. N., and L. I. Anatychuk. "Theoretical evaluation of maximum temperature difference in segmented thermoelectric coolers." Applied Thermal Engineering 26, no. 14-15 (2006): 1692–96. http://dx.doi.org/10.1016/j.applthermaleng.2005.11.009.

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KESETYANINGSIH, Tri Wulandari, Sri ANDARINI, Sudarto SUDARTO, and Henny PRAMOEDYO. "The Minimum-Maximum Weather Temperature Difference Effect on Dengue Incidence in Sleman Regency of Yogyakarta, Indonesia." Walailak Journal of Science and Technology (WJST) 15, no. 5 (2018): 387–96. http://dx.doi.org/10.48048/wjst.2018.2277.

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Dengue is a viral disease, transmitted by Aedes aegypti, and is still a big problem in tropical areas, including Indonesia, where the temperatures are relatively warm and suitable for vector mosquito life. In the dry season, the day and night temperature differences are quite sharp and, at that time, the number of dengue cases is low. In this study, the difference between day and night temperature is referred to as daily temperature fluctuation and represented by the maximum and minimum temperature difference in each month. The research was conducted in Sleman Regency, Yogyakarta Province, Indonesia, as an endemic area, and the data were collected from 4 endemic areas in Sleman; Gamping, Godean, Sleman, and Depok districts. The data collected were quantitative with serial data retrospective. Secondary data of monthly dengue incidence in the years 2008 - 2013 were obtained from the Regency Health Office and used as a dependent variable. Monthly minimum and maximum temperatures in the same periods were obtained from the Agency of Meteorology, Climatology, and Geophysics. The differences between the minimum and maximum temperatures were calculated, to be used as independent variable data, and represented the different day and night temperatures of the month. Data were analyzed by using linear regressions to determine the influence of fluctuating temperature on the incidence of dengue. Results show that fluctuating temperature affected dengue incidence in the districts of Godean (p = 0.000; R2 = 0.207) and Gamping (p = 0.006; R2 = 0.125), but did not affect it in Sleman (p = 0.164) or Depok (p = 0.075). The data suggests that fluctuating temperature affected dengue incidence with powers of 20.7 % in Godean and 12.5 % in Gamping.

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Hermansson, Åke. "Simulation Model for Calculating Pavement Temperatures Including Maximum Temperature." Transportation Research Record: Journal of the Transportation Research Board 1699, no. 1 (2000): 134–41. http://dx.doi.org/10.3141/1699-19.

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A simulation model has been developed to calculate the temperatures of asphalt concrete during summer. Input data to the simulation model are hourly values for solar radiation, air temperature, and wind velocity. Longwave radiation incident to and outgoing from the pavement surface is calculated from the air and pavement surface temperatures, respectively. The portion of the incident shortwave radiation absorbed by the pavement surface is calculated from the albedo of the surface. By means of a finite difference approximation of the heat transfer equation, the temperatures are calculated under the surface. Apart from radiation and heat transfer, convection losses from the pavement surface are also calculated depending on wind velocity, air temperature, and surface temperature. The formulas used for the calculation of radiation and the simulation model as a whole are validated by comparison with measurements, showing good agreement. A method for the calculation of direct solar radiation from a clear sky, at an arbitrary location and time, is used to create input data to the simulation model in order to calculate maximum pavement temperatures. The formulas used with Superpave to calculate maximum pavement temperatures are based on the assumption that there is an equilibrium when a maximum temperature is reached. Such an equilibrium assumption can be strongly questioned, and its consequences are discussed.

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Bakker, P., and H. Renssen. "Last Interglacial model-data mismatch of thermal maximum temperatures partially explained." Climate of the Past Discussions 10, no. 1 (2014): 739–60. http://dx.doi.org/10.5194/cpd-10-739-2014.

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Abstract. The timing of the Last Interglacial (LIG) thermal maximum is highly uncertain. Compilations of maximum LIG temperatures are therefore based on the assumption that maximum warmth occurred synchronously across the globe. Although known to be an oversimplification, the impact of this assumption on temperature estimates has yet to be assessed. We use the LIG temperature evolutions simulated by 9 different climate models to investigate whether the assumption of synchronicity results in a sizeable overestimation of LIG thermal maximum temperatures. We find that for annual temperatures, the overestimation is small, strongly model-dependent (global mean 0.4 ± 0.3 °C) and cannot explain the recently published 0.67 °C difference between simulated and reconstructed LIG thermal maximum temperatures. However, if one takes into consideration that temperature proxies are possibly biased towards summer, the overestimation of the LIG thermal maximum based on warmest month temperatures is non-negligible (global mean 1.1 ± 0.4 °C) and can at least partly explain the 0.67 °C global model-data difference.

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Di-Giovanni, F., P. G. Kevan, and G. É. Caron. "Estimating the timing of maximum pollen release from jack pine (Pinus banksiana Lamb.) in northern Ontario." Forestry Chronicle 72, no. 2 (1996): 166–69. http://dx.doi.org/10.5558/tfc72166-2.

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A practical heat sum method was validated for estimating the date of maximal pollen release of jack pine (Pinus banksiana Lamb.) in northern Ontario. The base temperature and start date that minimized differences between estimated and observed maximum pollen release dates were sought. Heat sums were calculated for all data sets (n = 26) for a range of base temperatures (1 to 20 °C) and start dates (January 1 to maximum pollen release). The best combination was a start date at Julian day 107 and base temperature at 4 °C. The heat sum to maximum pollen release was 288.58 degree days and the average difference between estimated and observed was 2.75 days. Recommendations for operational testing are made. Key words: heat sum, phenology, Piuns banksiana Lamb., temperature, pollen, dehiscence, contamination, seed orchard

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Lin, Chun Jing, Si Chuan Xu, Guo Feng Chang, and Zhao Li. "Thermal Characteristic Analysis of Rectangular and Large-Capacity Lithium-Ion Power Batteries." Advanced Materials Research 1044-1045 (October 2014): 448–56. http://dx.doi.org/10.4028/www.scientific.net/amr.1044-1045.448.

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Operating temperature and thermal uniformity have great effect on the performance, cycle life and safety of lithium-ion power batteries. In order to investigate the surface temperature change and distribution of a large-capacity and rectangular LiFePO4/C power battery, this paper conducts experiments on charging and discharging a battery module and cell at different current rates and various ambient temperatures. Results of thermalcouple-measurement show that temperature rising rates at different temperatures during charge and discharge change in accordance with the variation tendency of the resistance at different state of charge (SOC) and oprating temperatures. Under elevated ambient temperatures, the temperature excurtion and maximum temperature difference of the module are all smaller. Under the same ambient temperature, battery temperature at the end moment of discharge increases and the temperature uniformity of the module deteriorate at higher discharging rate. Temperature excurtion over the same time period is in a relationship of a standard quadratic function with the discharge current. Results of the thermal infrared imaging tests show that the maximum surface temperature differences at different discharging currents of 20A, 40A, and 80A are all above 5°C under natral convection heat transfer. The temperature of the lower part is higher than that of the upper part, while that of the central area is the highest. In a comprehensive charging and discharging scheme, the tendency of maximum surface temperature difference changes in accordance with that of the average surface temperature.

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Bartoszuk, Marian, and Wit Grzesik. "Numerical Prediction of the Interface Temperature Using Updated Finite Difference Approach." Advanced Materials Research 223 (April 2011): 231–39. http://dx.doi.org/10.4028/www.scientific.net/amr.223.231.

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This investigation is devoted to the heat flow problem occurring in dry orthogonal machining of a C45 medium carbon steel performed with uncoated single-point carbide tools. Finite Difference Approach (FDA) is applied to predict the variations of temperature distribution, and both average and maximum temperatures at the tool-chip interface, resulting from differentiating the heat flux configuration, and additionally the changes of thermal resistance along the tool-chip contact length. Moreover, some realistic computing errors due to possible measuring variations of the tool-chip contact length and the density and dimension of heat source on the shear plane were assessed and considered as input data in simulations. Finally, the measured values of temperatures using natural tool-work thermocouples have confirmed that the models proposed predict acceptably the average interface temperatures and estimate their maximum values for carbide tools.

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Xuan, X. C., K. C. Ng, C. Yap, and H. T. Chua. "The maximum temperature difference and polar characteristic of two-stage thermoelectric coolers." Cryogenics 42, no. 5 (2002): 273–78. http://dx.doi.org/10.1016/s0011-2275(02)00035-8.

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Morisaki, Takafumi, Takeshi Yasunaga, and Yasuyuki Ikegami. "Heat Source Temperature Difference and Maximum Power of Multi-stage Rankine Cycle." Proceedings of the Thermal Engineering Conference 2016 (2016): D214. http://dx.doi.org/10.1299/jsmeted.2016.d214.

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WANG, DAN, YU HAO, and JIANPEI WANG. "IMPACT OF CLIMATE CHANGE ON CHINA’S RICE PRODUCTION — AN EMPIRICAL ESTIMATION BASED ON PANEL DATA (1979–2011) FROM CHINA’S MAIN RICE-PRODUCING AREAS." Singapore Economic Review 63, no. 03 (2018): 535–53. http://dx.doi.org/10.1142/s0217590817400240.

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Climate change is attracting increasing attention from the international community. To assess the impact of climate change on China’s rice production, this paper re-organizes the main rice-producing areas by adding up the annual production of the provincial level regions between 1979 and 2011, utilizes Cobb–Douglas function using daily weather data over the whole growing season. Our analysis of the panel data shows that minimum temperatures (Tmin), maximum temperatures (Tmax), temperature difference (TD) and precipitation (RP) are the four key climate determinants of rice production in China. Among these, temperature difference is surprisingly significant and all except maximum temperatures have positive effects. However, because the actual minimum temperatures and precipitation in China’s main rice-producing areas declined while the maximum temperatures and the temperature difference increased during our sample period, climate change has actually provided a negative contribution to the increase in China’s rice production.

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Lian, Xu, Zhenzhong Zeng, Yitong Yao, Shushi Peng, Kaicun Wang, and Shilong Piao. "Spatiotemporal variations in the difference between satellite‐observed daily maximum land surface temperature and station‐based daily maximum near‐surface air temperature." Journal of Geophysical Research: Atmospheres 122, no. 4 (2017): 2254–68. http://dx.doi.org/10.1002/2016jd025366.

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Eck, Markus, Wolf-Dieter Steinmann, and Jürgen Rheinländer. "Maximum temperature difference in horizontal and tilted absorber pipes with direct steam generation." Energy 29, no. 5-6 (2004): 665–76. http://dx.doi.org/10.1016/s0360-5442(03)00175-0.

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Crane, Doug T., and Lon E. Bell. "Maximum temperature difference in a single-stage thermoelectric device through distributed transport properties." International Journal of Thermal Sciences 154 (August 2020): 106404. http://dx.doi.org/10.1016/j.ijthermalsci.2020.106404.

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Woo, Byung Chul, and Hee Woong Lee. "Relation Between Electric Power and Temperature Difference for Thermoelectric Generator." International Journal of Modern Physics B 17, no. 08n09 (2003): 1421–26. http://dx.doi.org/10.1142/s0217979203019095.

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The thermoelectric generation is the direct energy conversion method from heat to electric power. The conversion method is a very useful utilization of waste energy because of its possibility using a thermal energy below 423K. This research objective is to establish the thermoelectric technology on an optimum system design method and efficiency, and cost effective thermoelectric element in order to extract the maximum electric power from a wasted hot water. This paper is considered in manufacturing a thermoelectric generator and manufacturing of thermoelectric generator with 32 thermoelectric modules. It was also found that the electric voltage of thermoelectric generator with 32 modules slowly changed along temperature differences and the maximum power of thermoelectric generator using thermoelectric generating modules can be defined as temperature function.

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James, Richard P., and Anthony Arguez. "On the Estimation of Daily Climatological Temperature Variance." Journal of Atmospheric and Oceanic Technology 32, no. 12 (2015): 2297–304. http://dx.doi.org/10.1175/jtech-d-15-0086.1.

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AbstractThe climatological daily variance of temperature is sometimes estimated from observed temperatures within a centered window of dates. This method overestimates the true variance of daily temperature when the rate of seasonal temperature change is large, because the seasonal change within the date window introduces additional variance. The contribution of the seasonal change may be removed by performing the variance calculation using daily temperature anomalies, leading to a bias-free estimate of variance.The difference between the variance estimation methods is illustrated using both idealized simulations of temperature variability and observed historical temperature data. The simulation results confirm that removing the climatological temperature cycle eliminates bias in the variance estimates. For several U.S. midlatitude locations, the difference in estimated standard deviation of daily mean temperature is on the order of a few percent near the seasonal peaks in climatological temperature change, but the maximum difference is larger in highly continental climates. These differences are shown to be significant when estimating the probability of temperature extremes under the assumption of a Gaussian distribution.

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Lindström, Anders, and Erik Troeng. "Temperature variations in planting mounds during winter." Canadian Journal of Forest Research 25, no. 3 (1995): 507–15. http://dx.doi.org/10.1139/x95-057.

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Soil temperatures were measured at a depth of 8 cm in top, middle, and bottom positions of 30 cm high mineral and organic mounds and at 8 cm depth in scarified patches during winter and spring 1987–1988 and 1988–1989. At low air temperature, frozen mounds without snow cover showed much lower temperatures than snow-covered mounds, the maximum difference being 16 °C. During the coldest period of the two winters, when minimum air temperature was −26 °C, soil temperature in the top of a snowless mineral mound remained within −16 to −10 °C for 3.5 days and −8 to −5 °C in a snowless scarified patch. Minimum temperatures were lower, duration of low temperature freezing was longer, and temperature changes were more rapid in mineral than in organic mounds. Large temperature differences were found between the top and the bottom of mounds. In dry conditions during early spring, the upper part of the mineral mound thawed and froze repeatedly with daily maximum and minimum temperatures of 5 °C and −6 °C. Soil temperature patterns during the winter period are discussed in relation to root freezing tolerance of conifer seedlings. Mounding as a scarification method should be used with care as winter temperatures may injure seedling root systems.

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Lee, Jeong-Joo, Ji-San Kim, Hyuk-Kyun Chang, Dong-Chan Lee, and Chang-Wan Kim. "The Effect of Tab Attachment Positions and Cell Aspect Ratio on Temperature Difference in Large-Format LIBs Using Design of Experiments." Energies 14, no. 1 (2020): 116. http://dx.doi.org/10.3390/en14010116.

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Large-format lithium-ion batteries (LIBs) suffer from problems in terms of their product life and capacity due to large temperature differences in LIB cells. This study analyzes the effect of design factors on temperature distribution using a 3D electrochemical–thermal model. The design of experiments methodology is used to obtain the sampling points and analyze the effect of the cell aspect ratio, negative tab attachment position, and positive tab attachment position. These were considered as design factors for the maximum and minimum temperatures, as well as their difference, in large-format LIB cells. The results reveal that the cell aspect ratio, negative tab attachment position, and positive tab attachment position considerably influence temperature distribution. The cell aspect ratio has the most significant effect on the temperature distribution by changing the longest current pathway and the distance between tabs and the lowest temperature point in the LIB cell. A positive tab attachment position affects the maximum temperature, minimum temperature, and the temperature difference due to the heat generation caused by the high resistance of aluminum, which the positive tab is made. Furthermore, a negative tab attachment position affects the minimum temperature due to low resistance.

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Kon, Hirokazu, and Hideki Saito. "Test of the temperature difference model predicting masting behavior." Canadian Journal of Forest Research 45, no. 12 (2015): 1835–44. http://dx.doi.org/10.1139/cjfr-2015-0118.

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The differential temperature (ΔT) model, based on the assumption that masting plants respond to the difference in the temperatures during the growing seasons 1 and 2 years prior to seed production, has recently been proposed to explain the proximate factor of masting. In this study, we used a 28-year series of data on pollen cone and seed production in Cryptomeria japonica D. Don in Japan and compared several models based on temperatures and resources to test whether ΔT acts as a cue or is a proxy for resource limitation. Of all the models tested, models including ΔT, previous summer absolute temperature Tn–1, and reproduction in the previous year provided the best fit. The number of pollen cones and seeds produced was proportional to the difference in the mean daily maximum temperature during June to August between the preceding two years. In addition, to test whether the double mast events in consecutive years was less common than consecutive warm summers, we used our dataset and 12 datasets of pollen dispersal of 17 years or longer of C. japonica in Japan. Although consecutive warm summers occurred in 4.4% of pairs, double mast events occurred in 1.0%. The ΔT model was a considerably better predictor of the rare phenomenon of double mast events, which occur only after a specific sequence of cold–moderate–hot absolute summer temperatures. Thus, ΔT acts as cue for masting in C. japonica.

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Guo, Qiao Neng, Shi E. Yang, Qiang Sun, Yu Jia, and Yu Ping Huo. "Effect of Temperatures on Tensile of Aluminium Thin Films." Advanced Materials Research 528 (June 2012): 135–39. http://dx.doi.org/10.4028/www.scientific.net/amr.528.135.

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The mechanical process of single-crystal aluminium thin films under uniaxial tensile strain was simulated with molecular dynamics method at different temperature. The stress–strain curve and potential energy–strain curve of thin aluminium film under uniaxial tensile deformation were obtained by molecular dynamics simulations. With the changes of sample temperatures in uniaxial extension, the variation characteristics of stress–strain curves are alike at the elastic stage and different at the plastic one below and above 370 K, respectively. From the stress–strain curves, we gained the first local maximum stress-temperature curve and the strain at the first local maximum stress-temperature curve, and found that the strange temperature dependence of first local maximum stress: when the temperature is above 370 K, the stress goes down quickly with temperature, and when below 370 K, it descends slowly. With increasing temperature, the difference between two strain values corresponding to two maximal potential energies changes slowly below and above 370K but it goes up quickly about 370K. By these dependences, we have identified the critical temperature （370K） for the transition of plastic flow mechanism.

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Zhao, Lei, Lu Sun, and Tong Jiang Fan. "Temperature Field Analysis of CRTS-II Ballastless Track Slab Structure on Soil Subgrade." Applied Mechanics and Materials 587-589 (July 2014): 1255–61. http://dx.doi.org/10.4028/www.scientific.net/amm.587-589.1255.

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Temperature changes have a significant impact on the CRTS-II track structure in Beijing-Shanghai high-speed railway which has longitudinally connected type. In this paper temperature fields of ballastless track superstructure are simulated based on heat transfer theory and subroutine of ABAQUS that solar radiation DFLUX and ambient temperature FILM. The results showed that: the maximum temperature difference on the top of track slab is 20°C in summer and 10°C in winter; the maximum temperature difference in CA mortar layer is 4°C in summer and 2°C in winter; the maximum temperature difference in concrete substrate is 2°C in summer and 1°C in winter.

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Mino, M., T. Tanaka, and M. Homma. "Difference between temperature dependences of both initial permeability and maximum permeability of sendust alloys." IEEE Transactions on Magnetics 21, no. 3 (1985): 1240–44. http://dx.doi.org/10.1109/tmag.1985.1063880.

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Zhao, Xueying, Aiqin Shen, and Baofu Ma. "Temperature Adaptability of Asphalt Pavement to High Temperatures and Significant Temperature Differences." Advances in Materials Science and Engineering 2018 (July 8, 2018): 1–16. http://dx.doi.org/10.1155/2018/9436321.

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Temperature adaptability of asphalt pavements is very important, due to their potential influence on pavement structure design, particularly in areas that experience significant temperature differences. In this paper, a finite element (FE) model was developed, and Turpan-Xiaocao Lake Highway in southern Xinjiang was taken as a case study engineering, which tends to experience this adverse environmental condition (temperature difference: 25.5°C; July 14, 2008). In this model, the generalized Kelvin model and the Burgers model were used. The time-dependent tire pressure was considered. To guide pavement structure design and control pavement distresses in this area, seven alternative pavement structures were selected to simulate and analyze pavement temperature fields and the mechanical responses. It was observed that the influence of air temperature had the greatest impact on Str-1, possibly due to the thinnest asphalt course. Moreover, when rutting depth, maximum shear stress of the asphalt course, deflection on the pavement surface, and compressive strains at the subgrade top surface were taken as the evaluation indices, the adaptability of asphalt pavements using compound base courses had obvious advantage due to their strong absorption and reflection of load impact. The adaptability of seven structures analyzed in this paper decreased in the following order: Str-5 > Str-6 > Str-4 > Str-2 > Str-m > Str-1 > Str-3. In addition, it broke the traditional view that asphalt pavement with a flexible base had the poor ability on rutting resistance. Besides, it also suggests that when the thickness of asphalt courses was equivalent, increasing the thickness of chemical-treated base courses would help with the deformation resistance, and vice versa.

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Rust, Henning W., Tim Kruschke, Andreas Dobler, Madlen Fischer, and Uwe Ulbrich. "Discontinuous Daily Temperatures in the WATCH Forcing Datasets." Journal of Hydrometeorology 16, no. 1 (2015): 465–72. http://dx.doi.org/10.1175/jhm-d-14-0123.1.

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Abstract The Water and Global Change (WATCH) forcing datasets have been created to support the use of hydrological and land surface models for the assessment of the water cycle within climate change studies. They are based on 40-yr ECMWF Re-Analysis (ERA-40) or ECMWF interim reanalysis (ERA-Interim) with temperatures (among other variables) adjusted such that their monthly means match the monthly temperature dataset from the Climatic Research Unit. To this end, daily minimum, maximum, and mean temperatures within one calendar month have been subjected to a correction involving monthly means of the respective month. As these corrections can be largely different for adjacent months, this procedure potentially leads to implausible differences in daily temperatures across the boundaries of calendar months. We analyze day-to-day temperature fluctuations within and across months and find that across-months differences are significantly larger, mostly in the tropics and frigid zones. Average across-months differences in daily mean temperature are typically between 10% and 40% larger than their corresponding within-months average temperature differences. However, regions with differences up to 200% can be found in tropical Africa. Particularly in regions where snowmelt is a relevant player for hydrology, a few degrees Celsius difference can be decisive for triggering this process. Daily maximum and minimum temperatures are affected in the same regions, but in a less severe way.

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Mazhar, Nausheen, Dania Amjad, Kanwal Javid, Rumana Siddiqui, Muhammad Ameer Nawaz, and Zaynah Sohail Butt. "Mapping Fluctuations of Hispar Glacier, Karakoram, using Normalized Difference Snow Index (NDSI) and Normalized Difference Principal Component Snow Index (NDSPCSI)." International Journal of Economic and Environmental Geology 11, no. 4 (2021): 48–55. http://dx.doi.org/10.46660/ijeeg.vol11.iss4.2020.516.

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Investigation of the fluctuations in the snow-covered area of the major glaciers of the Karakoram range is essential for proper water resource management in Pakistan, since its glaciers are responding differently to the rising temperatures. The objective of this paper is to map snow covered area of Hispar glacier in Hunza river basin for the years 1990, 2010 and 2018. Two techniques, (NDPCSI) Normalized Difference Principal Component Snow Index and (NDSI) Normalized Difference Snow Index were used. Hispar glacier of the Hunza basin has lost 114 km2 of its ice cover area, during the last 28 years, with an alarming annual retreat rate of 1.67 km2 of glacier ice from 1990 to 2018. Hunza basin experienced a +1°C rise in both mean minimum and mean maximum temperature during 2007 to 2018.as a result, Karakorum ice reserves have been affected by rising temperature of the region. Due to temperature rise, retreat of snowcovered area of Hispar, Karakoram mountain range shows a shift in the cryospheric hazard zone.

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Kalburtji, K. L., J. A. Mosjidis, and A. P. Mamolos. "Effects of day-night temperature combinations under constant day length on emergence and early growth of sericea lespedeza genotypes." Canadian Journal of Plant Science 87, no. 1 (2007): 77–81. http://dx.doi.org/10.4141/p05-208.

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Establishment of sericea lespedeza [Lespedeza cuneata (Dumont de Courset) G. Don.] in southeastern USA is difficult. Seedling emergence may be related to the range of temperatures prevalent during establishment. A growth chamber study was undertaken to measure the effect of temperature on seedling emergence of 56 sericea lespedeza genotypes. Main treatments were: (1) plants grown at three day-night temperature combinations with maximum/minimum temperature difference of 14°C. The temperature combinations were 22/8°C, 27/13°C, and 32/18°C; (2) plants grown at three day-night temperature combinations with maximum/minimum temperature difference of 7°C. This was accomplished by lowering the day temperature and keeping the night temperature the same as above. Emergence was reduced by about 27% with reduction of 7°C in day-night temperature within the range of temperatures used. Plant height, leaf dry weight, stem dry weight and number of branches were very sensitive to temperature combinations. Increases in temperature caused increases in height, leaf dry weight, stem dry weight and number of branches of all genotypes. Further screening of sericea for emergence and growth under low temperature may lead to cultivars with more vigorous seedlings that can be better established early in the season. Key words: Plant growth, temperatures, seedling emergence, Sericea, southern USA

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Ronoh, Erick K., Christopher L. Kanali, and Samuel N. Ndirangu. "Effectiveness of an evaporative charcoal cooler for the postharvest preservation of tomatoes and kales." Research in Agricultural Engineering 66, No. 2 (2020): 66–71. http://dx.doi.org/10.17221/52/2019-rae.

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The preservation of fresh produce can provide rural households with better diets all-year round and income by reducing their deterioration. Promotion of low-cost temporary storage technologies requires evidence of their eﬀectiveness to attain conducive conditions. Therefore, this study was conducted to assess the effectiveness of an evaporative charcoal cooler for the preservation of tomatoes and kales. The cooler microclimate and outdoor conditions were investigated by measuring the air temperature and relative humidity. During the study period, the maximum temperature difference between the cooler and the outdoors was found to be 9.2 °C while the maximum relative humidity difference was 36.8%. Due to the presence of light rain and, consequently, low solar radiation, the temperature and relative humidity differences were significantly reduced. Despite the light rain, the cooler still registered a maximum relative humidity of 83.5% and a maximum cooling efficiency of 91.5%. Overall, the cooler demonstrated promising results in terms of favourable microclimate conditions, the shelf-life and colour changes for tomatoes and kales.

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Bakker, P., and H. Renssen. "Last interglacial model–data mismatch of thermal maximum temperatures partially explained." Climate of the Past 10, no. 4 (2014): 1633–44. http://dx.doi.org/10.5194/cp-10-1633-2014.

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Abstract. The timing of the last interglacial (LIG) thermal maximum across the globe remains to be precisely assessed. Because of difficulties in establishing a common temporal framework between records from different palaeoclimatic archives retrieved from various places around the globe, it has not yet been possible to reconstruct spatio-temporal variations in the occurrence of the maximum warmth across the globe. Instead, snapshot reconstructions of warmest LIG conditions have been presented, which have an underlying assumption that maximum warmth occurred synchronously everywhere. Although known to be an oversimplification, the impact of this assumption on temperature estimates has yet to be assessed. We use the LIG temperature evolutions simulated by nine different climate models to investigate whether the assumption of synchronicity results in a sizeable overestimation of the LIG thermal maximum. We find that for annual temperatures, the overestimation is small, strongly model-dependent (global mean 0.4 ± 0.3 °C) and cannot explain the recently published 0.67 °C difference between simulated and reconstructed annual mean temperatures during the LIG thermal maximum. However, if one takes into consideration that temperature proxies are possibly biased towards summer, the overestimation of the LIG thermal maximum based on warmest month temperatures is non-negligible with a global mean of 1.1 ± 0.4 °C.

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Kumar, Ravind, Mark Stephens, and Tony Weir. "Temperature trends in Fiji: a clear signal of climate change." South Pacific Journal of Natural and Applied Sciences 31, no. 1 (2013): 27. http://dx.doi.org/10.1071/sp13002.

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This paper analyses trends in temperature in Fiji, using data from more stations (10) and longer periods (52-78 years) than previous studies. All the stations analysed show a statistically significant trend in both maximum and minimum temperature, with increases ranging from 0.08 to 0.23°C per decade. More recent temperatures show a higher rate of increase, particularly in maximum temperature (0.18 to 0.69°C per decade from 1989 to 2008). This clear signal of climate change is consistent with that found in previous studies of temperatures in Fiji and other Pacific Islands. Trends in extreme values show an even stronger signal of climate change than that for mean temperatures. Our preliminary analysis of daily maxima at 6 stations indicates that for 4 of them (Suva, Labasa, Vunisea and Rotuma) there has been a tripling in the number of days per year with temperature >32°C between 1970 and 2008. The correlations between annual mean maximum (minimum) temperature and year are mostly strong: for about half the stations the correlation coefficient exceeds 60% over 50+ years. Trends do not vary systematically with location of station. At all 7 stations for which both trends are available there is no statistically significant difference between the trends in maximum and minimum temperatures.

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Shah, Ramesh K., and Teodor Skiepko. "Exchanger Performance Behavior Through Irreversibility Analysis for 1-2 TEMA G Heat Exchangers." Journal of Heat Transfer 127, no. 12 (2005): 1296–304. http://dx.doi.org/10.1115/1.2098827.

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The objective of this paper is to illustrate, discuss, and explain the interrelationship between the temperature difference irreversibility and heat exchanger effectiveness to clarify the performance trends of exchangers with some complex flow arrangements. This is because there is no physical explanation provided for the following results presented by Shah and Skiepko (ASME J. Heat Transfer, 126, pp. 994–1002, 2004): the heat exchanger effectiveness can be maximum, having an intermediate value or minimum at the maximum irreversibility operating point depending upon the flow arrangement of two fluids; similarly, the heat exchanger effectiveness can be minimum or maximum at the minimum irreversibility operating point. The analysis of such complex performance behavior is presented in this paper with an example of overall parallelflow and counterflow 1-2 TEMA G exchangers. This is accomplished by the decomposition of complex flow arrangements into simple subexchangers, and then the overall irreversibility trends for the exchangers are explained by irreversibilities produced due to temperature difference and fluid mixing in component subexchangers. It is shown for 1-2 TEMA G exchangers that the temperature difference irreversibility for a pure parallelflow subexchanger passes through a maximum at finite value of NTU1, and then approaches 0 when NTU1→∞. On the contrary, the irreversibility for a pure counterflow subexchanger attains a minimum value at finite NTU1 and then increases with NTU1 and approaches maximum at NTU1→∞ for 1–2 TEMA G exchangers. This is because the temperatures at the inlet of the subexchangers are variable and dependent on the exit temperatures from the preceding subexchangers. Detailed exchanger effectivenesses and temperature ratios are presented as a function of NTU1 for the explanation.

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Jofriet, J. C., S. Jiang, and S. W. Tang. "Finite element prediction of temperature gradients in walls of cylindrical concrete storage structures." Canadian Journal of Civil Engineering 18, no. 1 (1991): 12–19. http://dx.doi.org/10.1139/l91-002.

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Aboveground concrete cylindrical storage tanks must be designed for temperature differences between inside and outside faces of the wall. The stresses in the cylinder wall are a linear function of the temperature difference. A number of transient heat transfer finite element analyses were carried out to determine reasonable design values for this temperature difference. Extreme summer and winter conditions for southern Ontario were assumed in the analyses. It was found that for water stand-pipes supplied by groundwater the temperature difference can be as high as 25 °C, based on a summer water temperature of 10 °C. The maximum winter temperature difference was also 25 °C, based on a winter water temperature of 5 °C. For farm tower silos, a design temperature difference of 15 °C is probably more appropriate. Storage structures for other liquids can be judged if the temperature of the contained liquid is known. Key words: standpipes, structural design, temperature load, water reservoir, finite element prediction.

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Li, Yang, Hua Qing Xie, Wei Yu, and Jing Li. "Investigation on Heat Transfer Performances of Nanofluids in Solar Collector." Materials Science Forum 694 (July 2011): 33–36. http://dx.doi.org/10.4028/www.scientific.net/msf.694.33.

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Nanofluids containing Al2O3, ZnO, and MgO nanoparticles were prepared with distilled water as base fluid by violent stirring and ultrasonic dispersing. The forced convective heat transfer performances of the as-prepared nanofluids in tubular solar collector were investigated. The experimental results showed that the heat transfer efficiencies of Al2O3, ZnO, and MgO nanofluids were all increased in comparison to distilled water. For 1.0% vol. Al2O3, ZnO, and MgO nanofluids, the difference in temperature between nanofluids and distilled water all could exceed 3 °C in a day’s cycling. In daytime, from 6:00 a.m. to 18:00 p.m., the maximum differences in temperature of nanofluids and distilled water appeared at about 10:00 a.m., while the maximum temperatures were achieved at about 15:00 p.m. for both nanofluids and distilled water. In night, the temperatures of nanofluids still keep more than 1 °C higher than distilled water, which indicated that nanofluids could retain more heat energy. The viscosities and heat transfer efficiencies augmented with concentration increasing for ZnO nanofluids. Even at 0.2% vol. concentration, the difference in temperature between ZnO nanofluids and distilled could reach 2.55 °C. Based on low viscosity and excellent heat transfer performance, 0.2% vol. concentration ZnO nanofluid was an attractive option to be applied in solar energy utilization.

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Sartini, Claudio, Richard W. Morris, Peter H. Whincup, et al. "Association of Maximum Temperature With Sedentary Time in Older British Men." Journal of Physical Activity and Health 14, no. 4 (2017): 265–69. http://dx.doi.org/10.1123/jpah.2016-0468.

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Background:Sedentary behavior is very common in older adults and a risk factor for mortality. Understanding determinants of sedentary behavior may help in defining strategies aimed to reduce the time spent sedentary. The degree of difference in sedentary time attributable to varying temperatures has not been yet estimated in older men.Methods:Men aged 71 to 91 years participating in an established UK population-based cohort study were invited to wear an Actigraph GT3X accelerometer for 1 week in 2010–12. Outcome was sedentary time (<1.5 Metabolic Equivalent of Task) in minutes per day. Associations between daily outdoor maximum temperature and accelerometer-measured sedentary time were estimated using multilevel models.Results:43% (1361/3137) of invited men participated in the study and provided adequate data. Men spent on average 615 minutes in sedentary time per day (72% of the total accelerometer-wear time). After adjusting for covariates, men spent 26 minutes more per day (P < .001) in sedentary time when temperatures were in the lowest (–3.5; 9.2°C) versus highest quintile (19.1; 29.5°C).Conclusions:Sedentary time in older adults is highest at lowest temperatures, typically recorded in winter. Findings are relevant for guidelines: interventions may consider targeting older men in winter providing recommendations for minimizing sedentariness on daily basis.

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Pleșca, Adrian. "Considerations about Maximum Temperature of Toroidal Transformers in Steady-State Conditions." Journal of Advanced Thermal Science Research 7, no. 1 (2020): 22–29. http://dx.doi.org/10.15377/2409-5826.2020.07.3.

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In this paper, a novel method based on a thermal mathematical model which includes the main geometrical, physical and thermal parameters of the toroidal transformer has been developed in order to obtain the maximum temperature inside the transformer during steady-state operating conditions. The influence of electric current and ambient temperature on the maximum temperature has been investigated. To validate the proposed method, some experimental tests have been done. The analyzed transformer had a rated power of 2kVA and the rated primary voltage of 230V. There is a good correlation between experimental and theoretical results with a maximum difference of 3°C.

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Thapa, A., A. Silwal, S. P. Gautam, C. K. Nepal, S. Bhattarai, and D. Timsina. "Surface air temperature trends in Kathmandu Valley for 2011-2017." BIBECHANA 18, no. 2 (2021): 95–104. http://dx.doi.org/10.3126/bibechana.v18i2.29495.

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In this study, we reviewed the maximum and minimum temperature trends of the Kathmandu valley over the period of 2011-2017. In addition, the average monthly temperature trends were studied annually for the same period, with the data made available from the Department of Hydrology and Meteorology (DHM) of Nepal. The annual temperature trended in the same direction, with winter temperatures being lower and summer temperatures being higher. The annual average minimum and maximum air temperature trends were found to be slightly rising at 0.097˚C/year and 0.04˚C/year, respectively. The mean air temperature in Kathmandu valley is increasing at a rate of 0.06 degrees Celsius per year, with 2016 being the warmest year and 2012 being the least warm, with annual mean temperatures of 19.82˚C and 19.32˚C, respectively. The temperature difference is much smaller in the summer (less than ~12˚C) than in the winter.  BIBECHANA 18 (2) (2021) 95-104

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Hu, Wei, Jian Hang Hu, Hua Wang, Kun Sang, Juan Qin Li, and Shuang Hui Deng. "Experimental Research on Molding Biomass’s Carbonization Homogeneity." Advanced Materials Research 634-638 (January 2013): 759–63. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.759.

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Molding biomass’s carbonization homogeneity was studied through doing research on temperature difference of surface and inside of biomass by making experiments. Molding biomass’s size is larger than that of small dimension biomass and carbonization in whole biomass is different to some extent. But endothermic and exothermic effect in pyrolysis process and mass transfer of volatile are beneficial to carbonization homogeneity. When biomass average heating rate becomes larger, the maximum temperature difference of surface and inside becomes larger, besides that the temperature of biomass is higher when molding biomass’s carbonization is homogeneous. Maximum temperature differences were 30, 76, 137 °C respectively when biomass average heating rates were 5, 10, 20 °C/min. In order to ensure homogeneity, carbonization should reach the temperature which lignin decomposes strongly at releasing heat violently. Carbonization temperature should be higher than 450 °C. Besides, biomass average heating rate shouldn’t be too high and it should be under 20 °C /min.

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Gan, Yu-Feng, and Jiin-Yuh Jang. "Optimal Heat Transfer Coefficient Distributions during the Controlled Cooling Process of an H-Shape Steel Beam." Advances in Materials Science and Engineering 2017 (2017): 1–15. http://dx.doi.org/10.1155/2017/9873283.

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Three-dimensional thermal-mechanical models for the prediction of heat transfer coefficient distributions with different size beams are investigated. H300 × 300, H250 × 250, and H200 × 200 H-shape steel beams are investigated in a controlled cooling process to obtain the design requirements for maximum uniform temperature distributions and minimal residual stress after controlled cooling. An algorithm developed with the conjugated-gradient method is used to optimize the heat transfer coefficient distribution. In a comparison with the three group results, the numerical results indicate that, with the same model and under the same initial temperature (T=850°C) and final temperature (T=550±10°C), the heat transfer coefficients obtained with the conjugated-gradient method can produce more uniform temperature distribution and smaller residual web stress, with objective functions of the final average temperature Tave±ΔT and maximum temperature difference to minimum min⁡ΔTmax(x,y). The maximum temperature difference is decreased by 57°C, 74°C, and 75°C for Case 1, Case 2, and Case 3, respectively, the surface maximum temperature difference is decreased by 60~80°C for three cases, and the residual stress at the web can be reduced by 20~40 MPa for three cases.

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R. Abid, Sallal, Faten I. Mussa, and Nildem Tayşi. "Experimental Investigation of Thermal Response of Encased Composite Beams." International Journal of Engineering & Technology 7, no. 4.20 (2018): 108. http://dx.doi.org/10.14419/ijet.v7i4.20.25858.

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Many types of structures, or part of which, are directly under the exposure of the time-dependent variations of the temperature of air and solar radiation. Such thermal loads can vary the temperature of the different parts of the structural members causing undesired structural effects. In this research, an experimental study was conducted to investigate the influence of such thermal loads on composite beams. For this purpose, a concrete-encased-steel beam was instrumented with fifteen thermocouples and other sensors. The records were captured for a sunny winter day with moderately high daily air temperature difference of more than 18 oC and a solar radiation of more than 700 W/m2. The results showed that the hourly temperature variation and the sun movement in addition to the altitude angle of sun rays control the vertical and lateral temperature distributions of the beam. The maximum recorded difference between hourly maximum and minimum temperatures of the beam was 12.5 oC.

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Wang, Y., and K. Vafai. "An Experimental Investigation of the Transient Characteristics on a Flat-Plate Heat Pipe During Startup and Shutdown Operations." Journal of Heat Transfer 122, no. 3 (2000): 525–35. http://dx.doi.org/10.1115/1.1287725.

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This work presents an experimental investigation of the thermal performance of a flat-plate heat pipe during startup and shutdown operations. Using the analytical model developed in a previously study, analytical and experimental results on the effect of input power and cooling heat transfer coefficient on the thermal performance of the heat pipe are presented and discussed. The results indicate that the wick in the evaporator section provides the largest resistance to the heat transfer process followed by the wick in the condenser section. It is found that the heat transfer coefficient has an insignificant effect on the maximum temperature difference across the heat pipe where this difference refers to the maximum difference on the outside surfaces of the flat-plate heat pipe. However, as expected, the input heat flux has a substantial effect on the temperature rise where the temperature rise refers to the temperature increase on the outside surface of the heat pipe. It is found that the temperature difference across the heat pipe depends mainly on the input power. The heat transfer coefficient strongly affects the time it takes to reach steady state while input power has a substantially smaller effect. Empirical correlations for the maximum temperature rise, the maximum temperature difference and the time constants are obtained. The experimental results are compared with the analytical results and are found to be in very good agreement. [S0022-1481(00)01803-X]

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Elliott, N. C., J. J. Jackson, and R. D. Gustin. "PREDICTING WESTERN CORN ROOTWORM BEETLE (COLEOPTERA: CHRYSOMELIDAE) EMERGENCE FROM THE SOIL USING SOIL OR AIR TEMPERATURE." Canadian Entomologist 122, no. 6 (1990): 1079–91. http://dx.doi.org/10.4039/ent1221079-11.

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AbstractA temperature-dependent multiple cohort simulation model was used to predict emergence of western corn rootworms, Diabrotica virgifera virgifera LeConte, from the soil. Hourly 10-cm-depth soil temperatures were used as input to the model. Hourly soil temperatures were predicted from daily minimum and maximum 10-cm-depth soil temperatures using a half-sine-wave approximation, or from minimum and maximum daily 1-m-height air temperatures using a model for predicting soil temperature from air temperature. The mean difference in the number of days between predicted and observed 50% emergence was 0.22 days using soil temperatures and 0.00 days using air temperatures. Linear regressions of predicted versus observed Julian dates of 10, 50, and 90% cumulative beetle emergence from the soil indicated that model predictions were reasonably accurate and precise using both soil and air temperatures.

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Widyasamratri, H., K. Souma, T. Suetsugi, et al. "Heat and dry islands observed over Jakarta, Indonesia, in 2012." Proceedings of the International Association of Hydrological Sciences 364 (September 16, 2014): 140–44. http://dx.doi.org/10.5194/piahs-364-140-2014.

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Abstract. Recent population increases in urban areas of Asian countries have extended artificial land cover, increased energy consumption, and caused various problems. Higher air temperatures over urban areas (heat islands) degrade residential environments and affect human health. In Jakarta, the largest city in Indonesia and the second largest city in Asia, previous studies have relied on only a few observation points and physically-based models. To study the thermal environment in Jakarta in more detail, we performed seven fixed-point temperature and humidity observations from the dry to the pre-monsoon season (from 16 September to 18 October) in 2012. Over densely urbanized areas, higher temperatures and lower humidity were observed around noon compared with the sparsely urbanized areas. The maximum differences in temperature and specific humidity were found to be around 3 °C and 0.005 kg/kg, respectively. The differences in temperature and humidity became smaller in the afternoon because of the penetration of sea breezes. At night, the differences became larger again because the sea breeze weakened. Then, a difference of around 3°C was observed, except in the early morning. Although the difference in daytime temperature was smaller between densely urbanized areas and suburban areas, similar tendency was also confirmed in the daily time series averaged for sunny days in dry season.

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HINDERINK, KATJA, MIIA LINDSTRÖM, and HANNU KORKEALA. "Group I Clostridium botulinum Strains Show Significant Variation in Growth at Low and High Temperatures." Journal of Food Protection 72, no. 2 (2009): 375–83. http://dx.doi.org/10.4315/0362-028x-72.2.375.

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The minimum and maximum growth temperatures of 23 group I Clostridium botulinum strains of the toxin types A, AB, B, and F were determined. Moreover, the maximum growth rates at 20, 37, and 42°C of the same strains were recorded. The minimum growth temperatures varied from 12.8 to 16.5°C, whereas the maximum growth temperatures showed even wider variation, from 40.9 to 48.0°C. At 20 and 37°C, a twofold difference in maximum growth rates between the slowest and the fastest growing strains was found; at 42°C the difference was more than 30-fold. As expected, all strains grew significantly slower at 20°C than at 37°C. However, eight type B strains grew substantially faster at 42°C than they did at 37°C. These findings indicate that the optimum growth temperature for some group I C. botulinum type B strains is higher than the temperature of 37°C that is generally accepted. A significant correlation between maximum growth rates at 42°C and maximum growth temperatures was found for type B and F strains, whereas for type A strains no such correlation could be found. Strain variation was particularly high for the type B strains, reflecting the wide genetic diversity of this toxin type. The significant variation between strains of group I C. botulinum may have an impact on inoculation studies and predictive modeling when assessing the safety of foods.

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Liu, Yu, Xudong Wang, Yi Sun, et al. "Research on a new detection method of slab surface crack in mould during continuous casting." Metallurgical Research & Technology 115, no. 1 (2017): 108. http://dx.doi.org/10.1051/metal/2017082.

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Based on the mould temperature measured by thermocouples during slab continuous casting, a new thermograph with difference of temperature change is developed to detect slab cracks. This thermograph allows the characteristics of longitudinal crack during formation and propagation process to be captured and extracted by means of computer image processing algorithms, such as the maximum difference of temperature change, the mean difference of temperature change, height and width, aspect ratio and moving velocity. These characteristics are also compared to the normal and abnormal cold regions. The results show that the maximum and mean differences of temperature change are very large. The moving velocity is almost close to casting speed. The cold region is almost parallel to casting direction. The aspect ratio of cold region caused by longitudinal crack is very large, which is different to other abnormalities. These characteristics of abnormal regions can be used to judge longitudinal crack, normal continuous casting and other abnormalities. This method presents some visual characteristics of cold regions caused by longitudinal crack to operators clearly. Meanwhile, it also has a positive meaning to the intelligence and visualization of mould monitoring during slab continuous casting.

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Lü, Ming, and Zhi Ning. "On the thermal instability of supercavitating liquid jet surrounded by coaxial rotary gas." Journal of Mechanics 37 (2021): 551–65. http://dx.doi.org/10.1093/jom/ufab024.

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Abstract Based on the jet stability theory, under the conditions of gas rotation, fluid compressibility and supercavitation, this paper gives the mathematical model describing the thermal instability of supercavitating liquid jet surrounded by a coaxial rotary gas, and the corresponding numerical method for solving the mathematical model is proposed and verified by the data in reference. Then, this paper analyzes the effects of gas–liquid temperature differences and temperature gradients on jet instability, and studies the thermal stability of supercavitating jet. The results show that the maximum disturbance growth rate, the dominant frequency and the maximum disturbance wave numbers increase linearly with the increase of gas–liquid temperature differences. The existence of temperature gradient inside the jet makes the effects of temperature differences on jet instability more obvious. The temperature gradient will inhibit the effect of supercavitation on jet instability, while gas–liquid temperature difference will promote the effect of supercavitation on jet instability.

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Liu, Xiao Gen, and Yi Wang Bao. "Theoretical and Experimental Studies on Stresses in Vacuum Glazing due to Temperature Difference." Key Engineering Materials 591 (November 2013): 311–15. http://dx.doi.org/10.4028/www.scientific.net/kem.591.311.

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The existence of a temperature difference across a vacuum glazing causes dimensional differences between the hot and cold glass sheets, with associated mechanical stresses and bending. In order to understand the distribution characteristics of the stresses and deformation in vacuum glazing due to temperature difference, in this work, the mechanical models were established and the calculation formula of the shear stress in the edge seal and bending tensile stress on the surface of the two glass sheets of the vacuum glazing were given. A test device was designed and the maximum tensile stresses and deflection of the vacuum glazing with various temperature difference were tested by experimental, it was shown that they are identical between the experiments and the theories.

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Wang, Jing Fu, Yin Zhi Wang, Yong Zhang, and Ying Wang. "The Experimental Study on Performance of Single Screw Expander with Air as Working Fluid." Advanced Materials Research 634-638 (January 2013): 1659–64. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.1659.

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A new single screw expansion machine was developed in order to improve the practical level of low temperature thermal power generation technology and the utilization of waste heat and renewable energy. With compressed air as working fluid, the power, efficiency, gas consumption rate and temperature difference of single screw expander with rotational speed variation had been studied in an established experimental apparatus of single screw expander . The results showed that, the maximum speed of expander reached 3393r/min, the maximum moment of torque reached 22N•m, the maximum power of expander was up to 4.4kW, and the maximum inlet flow rate was 32.9m3/h. The maximum temperature difference between import and export of expander reached 45°C. The lowest gas consumption rate was up to 55.2kg/kW•h, and the maximum total efficiency of expander reached 58.8%.

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Choi, Changjin, and Nick Roberts. "Impact of Mass and Lattice Difference on Thermal Boundary Conductance." MRS Proceedings 1779 (2015): 45–52. http://dx.doi.org/10.1557/opl.2015.722.

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ABSTRACTThe impact of mass and lattice difference on thermal boundary conductance is investigated using non-equilibrium molecular dynamics with the Lennard-Jones interatomic potential. Results show that the maximum thermal boundary conductance is achieved when the mass and the lattice of two dissimilar materials are matched, although the composite thermal conductance is not necessarily a maximum. It is observed that the small difference in mass and potential well depth has as significant an impact as large differences, and that the frequency mismatch is an important factor that affects thermal boundary conductance. It is, also, found that inelastic scattering begins to play a role at the interface as the temperature increases.

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Yang, Zhao, Xiao Ping Xu, Chuan Li, et al. "On-Line Monitoring of Charge Unit by Using Fiber Bragg Grating Temperature Sensors." Advanced Materials Research 503-504 (April 2012): 1672–78. http://dx.doi.org/10.4028/www.scientific.net/amr.503-504.1672.

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The charge unit supply power when the power is cut off. It has been the necessary components in every type of substations to ensure the continuous operations of electric relays, automatic devices and circuit breakers. By using contacting electrical insulating Fiber Bragg Grating temperature sensor, the monitored equipment can be measured and controlled under the safe temperature. The temperatures of three fans and environment have been surveyed since June 6, 2010, in the charge unit of Yanjin substation’s main control room. The real-time monitoring of 24-hours indicates that the temperature changes in the range of 1°C. At the long-term of 479 days, the average daily minimum temperature range of three fans is 12.48°C, and the maximum range is 23.07°C. The maximum temperature is 39.14°C on April 30, 2011, and the minimum temperature is 23.98°C on January 10, 2011. The daily average of ambient temperature range is 12.04 °C, the maximum temperature is 38.38 °C on July 16, 2010, and the minimum temperature is 26.34 °C on January 9, 2011. The maximum difference between the temperature of fan and the ambient temperature is 7.60 °C on October 23, 2010. According to the relevant standards and monitoring results, the maximum threshold of fan temperature is defined to 85°C, and the threshold of temperature rise is 20°C.

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Chen, Chiachung. "Evaluation of the Effect of Temperature on a Stem Elongation Model of Phalaenopsis." Horticulturae 5, no. 4 (2019): 76. http://dx.doi.org/10.3390/horticulturae5040076.

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Phalaenopsis orchid has become one of the most important potted plants in flower markets. However, the timing at which flowers reach the saleable stage can be very important since the demand may be larger for specific holidays. The regulation of stem growth could serve as an opportunity for regulation of flowering. The purpose of this study was to evaluate the effect of temperature on stem elongation. In this study, a stem elongation model established by a statistical technique was used to evaluate the effect of temperature. The stem lengths of four named Phalaenopsi varieties and 15 unnamed Phalaenopsi hybrids were measured under different temperature regimes. The three parameters of the logistic growth model, the maximum stem length, growth rate, and inflection point at which the growth rate reached a maximum value were estimated by using nonlinear regression analysis. Then, the differences among varieties in these three parameters were assessed by categorical testing. The results of this study indicated that stem growth rate was positively affected only by day temperature. The maximum stem length was negatively affected by the day temperature and positively influenced by the temperature difference between day and night. The results of this study could provide a practical method to regulate stem elongation by adjusting the temperatures, thus helping growers time the flowering of their potted orchids to meet market demand.

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Chichko, A. N., S. G. Likhousov, O. A. Sachek, O. I. Chichko, and T. V. Matyushinets. "MODELING OF THE TEMPERATURE DISTRIBUTION DENSITY FUNCTION IN A DETAIL AT A CONSTANT HEATING TEMPERATURE." Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY), no. 2 (July 7, 2018): 57–64. http://dx.doi.org/10.21122/1683-6065-2018-2-57-64.

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The functions of the temperature distribution density of the detail on the basis of the results of numerical simulation of the heating process are calculated. Characteristics of the temperature distribution function of the detail for analysis of the level of formation of thermal stresses are proposed. It was shown that the difference between the maximum and minimum temperatures of the detail varies nonlinearly with the time of heating the detail in the furnace. The method for formalizing numerical simulation data for selecting the best thermal modes for heating details is proposed.

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Journal articles on the topic 'Maximum temperature difference'

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