Journal articles: 'Effect of heat'

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Gurney, Shae C., Katherine S. Christison, Tyler Stenersen, and Charles L. Dumke. "Effect of uncompensable heat from the wildland firefighter helmet." International Journal of Wildland Fire 30, no. 12 (2021): 990. http://dx.doi.org/10.1071/wf20181.

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Heat accumulation from wearing personal protective equipment can result in the development of heat-related illnesses. This study aimed to investigate factors of heat stress with and without a US standard issue wildland firefighter helmet. Ten male subjects finished a 90-min exercise protocol in a heat chamber (35°C and 30% relative humidity), with standard issue meta-aramid shirt and pants and a cotton t-shirt, and either with or without a wildland firefighter helmet. A randomised crossover design was implemented, with a minimum 2-week washout period. Heart rate, physiologic strain index, perceived head heat, head heat and skin blood flow of the head and neck were measured. At the conclusion of the 90-min trial, heart rate, physiological strain index, core temperature, rating of perceived exertion and perceived head heat showed a main effect of time (P &lt; 0.05). Perceived head heat and head heat exhibited a main effect of trial (P &lt; 0.05). The change in physiologic strain was positively correlated with the change in skin blood flow of the head (r = 0.72, P = 0.02). These data suggest that the current wildland firefighter helmet contributes to heat accumulation. The design of the wildland firefighter helmet lacks ventilation, which, from these data, may result in metabolic alterations and perceived discomfort.

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Shailendra Dubey Sonal, Ritik. "Effect of Solar Heat on Foliage Gas." International Journal of Science and Research (IJSR) 1, no. 3 (2012): 117–19. http://dx.doi.org/10.21275/ijsr12120345.

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Patil, Prithviraj, A. K. Mehta, Omkar Mane, Shiwani Dhumal, Sukanya Palve, and Tejaswini Patil. "Effect of Headgear on Physiological, Physical Response of Male Farm Worker Under Heat Stress Condition." Journal of Scientific Research and Reports 31, no. 1 (2025): 528–37. https://doi.org/10.9734/jsrr/2025/v31i12796.

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India has a vast geographical area with variations in climate and temperature from region to region. Summers are very harsh in many parts of the country where temperature exceeds 45°C. Most of the agricultural operations in the country are performed by manual labour in such a warm climate where it becomes difficult for the body to maintain its heat balance with the environment. In leads to heat stress many a time. Heat stress causes many heat disorders like systemic disorder, heat syncope, heat odema, heat cramp, heat exhaustion and heat stroke. To minimize heat stress in warm climate many techniques are used. One of them is the use of headgear which protects the head. Farmers are using towel, pagadi, caps etc. as headgear from the last many years. The independent parameters of the study were WBGT (28, 30 and 32oC), headgears (Bamboo hat, felt hat with 90 mm brim width, white pagdi and solar hat) and subject (10 male farm workers). The dependent parameters of study were heart rate, oxygen consumption rate and overall discomfort rating. The results of the research showed that use of headgear reduced the effect of heat stress significantly on physiological parameters and physical discomfort parameters.

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Sun, Jian, and Wei Qiang Liu. "Effect of Heat Leading of Windward Leading Edge Using Heat Pipe with Porous." Advanced Materials Research 217-218 (March 2011): 674–79. http://dx.doi.org/10.4028/www.scientific.net/amr.217-218.674.

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By the uses of finite element method and finite volume method, we calculated the solid domain and fluid domain of windward leading edge which is flying under one condition. And the paper proved that heat pipes which covered on the leading edge have effect on thermal protection. The maximum temperature of the head decreased 12.2%. And the minimum temperature of after-body increased 8.85%. Achieving the transfer of heat from head to after-body, the front head of the thermal load was weakened and the ability of leading edge thermal protection was strengthen. The effect of the thickness of heat pipe, black level of covering materials and equivalent thermal conductivity of heat pipes on the wall temperature were discussed for the selection of thermal protection materials of windward leading edge to provide a frame of reference.

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Tuska, Habib Syaiful Arif, Nursalsabila Khamalt, Muhammad Arfan Lesmana, et al. "Effect of Artemisia vulgaris Supplementation on Zebrafish Embryo Under Heat Stress Condition during In Vitro Culture." Journal of Applied Veterinary Science And Technology 5, no. 1 (2024): 20–25. http://dx.doi.org/10.20473/javest.v5.i1.2024.20-25.

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Background: Artemisia vulgaris contains flavonoids, which play a vital role in counteracting free radicals. Purpose: To determine the effect of Artemisia vulgaris extract supplementation on embryo development, heart rate and survival of zebrafish under heat stressed and non-heat stressed conditions. Methods: The research used a completely randomized design. Zebrafish embryos (n=240) were divided into heat stressed (36°C) and non-heat stressed (28°C) groups, while for each group were divided into three subgroups, namely T1/control (without Artemisia vulgaris supplementation); and supplemented group T1 and T2, with 2 µL and 4 µL of Artemisia vulgaris supplementation, respectively. The efficacy of Artemisia vulgaris supplementation was determined by observing the embryo development, heart rate, and survival rate of zebrafish up to 96 hours post fertilization (hpf). Results: The development of zebrafish embryos under heat stressed treated with Artemisia vulgaris extract gave the same quality as the control treatment without heat stressed exposure. Zebrafish embryos exposed to heat stressed with 4 µL Artemisia vulgaris supplementation gave the highest survival rate on the heat stressed group. Artemisia vulgaris supplementation improved the heart rate of zebrafish exposed to heat stressed as in the non-heat stressed group. Conclusion: Artemisia vulgaris extract can reduce the detrimental effects of heat stressed induction on zebrafish embryos, as evidenced by the improvement in embryonic development, heart rate, and survival rate of zebrafish embryos after supplementation.

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Fan, T. H., and F. B. Cheung. "Modeling of Transient Turbulent Natural Convection in a Melt Layer With Solidification." Journal of Heat Transfer 119, no. 3 (1997): 544–52. http://dx.doi.org/10.1115/1.2824137.

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The phenomenon of turbulent natural convection in a horizontal heat-generating melt layer with solidification taking place at the cooled upper and lower boundaries is investigated theoretically. The objective is to determine the transient behavior of the crust at the upper and lower surfaces and the effect of crust formation on the turbulent natural convection process in the melt layer. Various surface temperatures, latent heats, and the heat source strengths are considered along with the effects of the Stefan number and Rayleigh number. Special attention is given to the interaction between the melt pool heat transfer and the crust dynamics. Numerical results are presented for the transient crust thickness, transient temperature distribution, eddy heat transport, and the heat transfer characteristics at the solid-liquid interface during the freezing process. The present study provides basic information needed to predict the transient behavior of a melt pool in a reactor lower head following a severe core-meltdown accident.

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Safi, Ahmad. "Effect of Heat Stress in Poultry and Its Mitigation." Current Research in Agriculture and Farming 3, no. 6 (2022): 9–18. http://dx.doi.org/10.18782/2582-7146.179.

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The major problem for huge economic loss in the poultry industry was stress and from different types of stressors; heat stress was a major one. In this developing era, poultry played an important role in almost economic gain of every country. But with changing climatic conditions it had become hard to maintain the temperature in poultry production system. Heat stress effects the overall performance of both layers and broiler in terms of meat quality, growth, egg quality and egg production. If these types of parameters start showing in poultry farms timely taken steps will save farm from huge economic loss. Scientists are using different methods and techniques to alleviate the devastating effects of heat stress in both economically important poultry sectors, layer and broiler. Providing birds with suitable environmental conditions like proper ventilation and stocking density helps minimize HS. Supplementation of feed additives also helps in reducing damaging effects of HS by improving performance and gut health. Scientists worldwide are trying to develop birds with high heat tolerating ability so that birds will perform well during high-temperature phase. Conditioning of birds with high temperature at early age also helps the birds to perform better in later phases of life. This article highlights major issues regarding to chicken health under HS condition and some techniques to perform well under stressed conditions.

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Patil, Prithviraj, A. K. Mehta, Sukanya Palve, Omkar Mane, Shiwani Dhumal, and Tejaswini Patil. "Assessment of Heat Stress on Human Physiology, Thermal and Physical Discomfort of Male Farm Worker." Journal of Scientific Research and Reports 31, no. 1 (2025): 547–55. https://doi.org/10.9734/jsrr/2025/v31i12798.

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India is characterized by strong temperature variations in different seasons ranging from mean temperature of about 10°C in winter to about 32 °C in summer season. The temperatures start to increase all over the country in March and by April; the interior parts of the peninsula record mean daily temperatures of 30-35 °C. Heat stress is a condition that is caused by worker’s over-exposure to the high temperature work environments often found in outdoor agriculture operations. Workers should be informed of the nature of heat stress and its adverse effects as well as the protective measures provided in the workplace. This operation was performed by traditionally used manually operated sickle, when the average dry bulb temperature was above 32°C which caused the heat stress during the work because of high humidity in the field. Head temperature, forehead temperature, oral temperature, left lower hand temperature, middle left-hand temperature, upper right-hand temperature, left upper chest temperature, right scapula temperature, left calf temperature and right anterior thigh temperature were measured to assess the effect of environmental heat direct sun radiation on selected farm workers during both the agricultural operations. To assess the effect of heat on the human body, physiological parameters like heart rate (HR) and oxygen consumption rate (OCR). Thermal parameters like oral, head, left lower hand, middle left hand, upper right hand, left upper chest, right scapula, left calf, right anterior thigh, mean skin temperatures of farm workers increased with increase in WBGT due to heat stress.

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Almeida, Ronaldo André Castelo Dos Santos De, Jéssica da Silva Santos, Letícia de Sousa Amorim, Emerson Lopes Olivares, and Anderson Luiz Bezerra da Silveira. "Heat Therapy: Planned Heat Exposure as a Nonpharmacological Strategy against Ischemic Heart Events." Journal of Clinical and Preventive Cardiology 14, no. 1 (2025): 27–32. https://doi.org/10.4103/jcpc.jcpc_1_25.

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ABSTRACT It is known that the planned exposure to high temperatures favors organic adaptations to heat and promotes important hypotensive effects. The increasing number of heart disease patients and deaths due to ischemic heart events mobilizes studies aimed at discovering and improving new therapeutic procedures. Considering the high costs of pharmacological therapies, nonpharmacological strategies are a high-value and low-cost alternative. Combined with the known effects of physical exercise, heat therapy (HT) can significantly contribute to cardiovascular stabilization and cardioprotection. The goal of this short review is to consider the application of this nonpharmacological strategy as a protector of the cardiovascular system and cardiac function. The importance of the cardiovascular benefits of planned exposure to heat based on results from animal experiments and its effect on the preservation of cardiac function is highlighted. The findings demonstrated the benefits and highlighted the possibility of expanding the view of HT concerning cardioprotection.

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Akash, Thavare, and Bande Rahul. "STUDY ON EFFECT OF NANOFLUIDSON HEAT TRANSFER CHARACTERSTIC OF HEAT PIPE." JournalNX - A Multidisciplinary Peer Reviewed Journal QIPCEI2K18 (May 1, 2018): 246–51. https://doi.org/10.5281/zenodo.1412347.

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 With the increase in requirement of advanced technical equipment , of which there basic initial work is carried out on the applications, which used heat pipes for heat transfer. Heat pipes are one specific type of heat exchangers, having very wide application in electronics and other fields, because of its compactess, high efficiency, less number of components and no need for external circulation of working fluid. This heat pipes previously carrying conventional fluid as working medium inside them. But in recent years nanofluids in heat pipes have attracted a notable attention due to its superior heat transfer properties. https://journalnx.com/journal-article/20150618

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11

Kimura, T., and T. Nishioka. "The Chiral Heat Effect." Progress of Theoretical Physics 127, no. 6 (2012): 1009–17. http://dx.doi.org/10.1143/ptp.127.1009.

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12

Nuwayhid, R. Y., and F. Moukalled. "Effect of heat leak on cascaded heat engines." Energy Conversion and Management 43, no. 15 (2002): 2067–83. http://dx.doi.org/10.1016/s0196-8904(01)00146-7.

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13

Chandran, Deepak R. "The Effect of Thermal Interface Material on Led Heat Sinks." Journal of Advanced Research in Applied Mechanics & Computational Fluid Dynamics 05, no. 1&2 (2018): 1–5. http://dx.doi.org/10.24321/2349.7661.201801.

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14

A. Christy, Alfred. "Effect of Heat on the Adsorption Properties of Silica Gel." International Journal of Engineering and Technology 4, no. 4 (2012): 484–88. http://dx.doi.org/10.7763/ijet.2012.v4.416.

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15

Guo, Fuqiang, Chunyan Wang, and Bo Ren. "Effect of Heat Treatment Temperature on the Microstructure and Mechanical Properties of Cu0.3Cr2Fe2Ni3Mn2Nbx High-Entropy Alloys." Coatings 14, no. 8 (2024): 950. http://dx.doi.org/10.3390/coatings14080950.

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The effects of heat treatment temperature on the microstructure and mechanical properties of Cu0.3Cr2Fe2Ni3Mn2Nbx high-entropy alloys (HEAs) were studied. Results indicate that in the as-cast state, an Nb0 alloy is composed of a single FCC phase, and a Laves phase gradually forms as Nb content increases. After heat treatment at 800 °C, BCC solid solution phases rich in Cr, Fe, and Mn form in all alloys. The BCC phases in the Nb0.2 and Nb0.4 alloys decompose after heat treatment at 900 and 1000 °C, respectively, and the microhardness of the as-cast Cu0.3Cr2Fe2Ni3Mn2Nbx HEAs increases from 127 to 203 HV with increasing Nb content. After heat treatment, the microhardness of the alloys considerably improves, and the Nb0.4 alloy has the highest microhardness after heat treatment at 800 °C (approximately 346 HV). After heat treatment at 900 and 1000 °C, the microhardness of the three alloys decreases. The yield strength of the as-cast Cu0.3Cr2Fe2Ni3Mn2Nbx HEAs increases with Nb content and shows a trend of first increasing and then decreasing with increasing heat treatment temperature. The strengthening mechanism of the heat-treated alloys is mainly attributed to the second-phase strengthening of the Laves phase and the solid solution strengthening of the BCC phase.

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Wilson, Thad E., and Chester A. Ray. "Effect of thermal stress on the vestibulosympathetic reflexes in humans." Journal of Applied Physiology 97, no. 4 (2004): 1367–70. http://dx.doi.org/10.1152/japplphysiol.00403.2004.

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Both heat stress and vestibular activation alter autonomic responses; however, the interaction of these two sympathetic activators is unknown. To determine the effect of heat stress on the vestibulosympathetic reflex, eight subjects performed static head-down rotation (HDR) during normothermia and whole body heating. Muscle sympathetic nerve activity (MSNA; peroneal microneurography), mean arterial blood pressure (MAP), heart rate (HR), and internal temperature were measured during the experimental trials. HDR during normothermia caused a significant increase in MSNA (Δ5 ± 1 bursts/min; Δ53 ± 14 arbitrary units/min), whereas no change was observed in MAP, HR, or internal temperature. Whole body heating significantly increased internal temperature (Δ0.9 ± 0.1°C), MSNA (Δ10 ± 3 bursts/min; Δ152 ± 44 arbitrary units/min), and HR (Δ25 ± 6 beats/min), but it did not alter MAP. HDR during whole body heating increased MSNA (Δ16 ± 4 bursts/min; Δ233 ± 90 arbitrary units/min from normothermic baseline), which was not significantly different from the algebraic sum of HDR during normothermia and whole body heating (Δ15 ± 4 bursts/min; Δ205 ± 55 arbitrary units/min). These data suggest that heat stress does not modify the vestibulosympathetic reflex and that both the vestibulosympathetic and thermal reflexes are robust, independent sympathetic nervous system activators.

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Inoue, Hirotsugu, and Kikuo Kishimoto. "OS10-1-4 Effect of heat conduction on stress measurement based on the thermoelastic effect." Abstracts of ATEM : International Conference on Advanced Technology in Experimental Mechanics : Asian Conference on Experimental Mechanics 2007.6 (2007): _OS10–1–4——_OS10–1–4—. http://dx.doi.org/10.1299/jsmeatem.2007.6._os10-1-4-.

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Losnegard, Thomas, Martin Andersen, Matt Spencer, and Jostein Hallén. "Effects of Active Versus Passive Recovery in Sprint Cross-Country Skiing." International Journal of Sports Physiology and Performance 10, no. 5 (2015): 630–35. http://dx.doi.org/10.1123/ijspp.2014-0218.

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Purpose:To investigate the effects of an active and a passive recovery protocol on physiological responses and performance between 2 heats in sprint cross-country skiing.Methods:Ten elite male skiers (22 ± 3 y, 184 ± 4 cm, 79 ± 7 kg) undertook 2 experimental test sessions that both consisted of 2 heats with 25 min between start of the first and second heats. The heats were conducted as an 800-m time trial (6°, >3.5 m/s, ~205 s) and included measurements of oxygen uptake (VO2) and accumulated oxygen deficit. The active recovery trial involved 2 min standing/walking, 16 min jogging (58% ± 5% of VO2peak), and 3 min standing/walking. The passive recovery trial involved 15 min sitting, 3 min walk/jog (~ 30% of VO2peak), and 3 min standing/walking. Blood lactate concentration and heart rate were monitored throughout the recovery periods.Results:The increased 800-m time between heat 1 and heat 2 was trivial after active recovery (effect size [ES] = 0.1, P = .64) and small after passive recovery (ES = 0.4, P = .14). The 1.2% ± 2.1% (mean ± 90% CL) difference between protocols was not significant (ES = 0.3, P = .3). In heat 2, peak and average VO2 was increased after the active recovery protocol.Conclusions:Neither passive recovery nor running at ~58% of VO2peak between 2 heats changed performance significantly.

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Chernika, I.M., M.K. Bologa, O.I. Mardarskii, and I.V. Kozhevnikov. "Peculiarities of Nucleate Boiling Heat Transfer in Electroconvective Flow." Elektronnaya Obrabotka Materialov 55(2) (April 15, 2019): 44–51. https://doi.org/10.5281/zenodo.2629550.

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The effect of the electric field strength and interelectrode gap distance on the main parameters of the boiling process under electrohydrodynamic flow conditions is studied. It is established that an increase of the heat flux density results in a decrease of the field effect. The optimal interelectrode gap distance corresponding to the maximum heat transfer is found. The hydrodynamics of the two-phase flow and its influence on the heat transfer intensity is analyzed on the base of visual observations and high-speed filming of the process. The calculated dependences are in satisfactory agreement with the experimental results.

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MA, Xinling, Xinli WEI, Xiangrui MENC, and Yao YAO. "C305 ANALYSIS OF PERFORMANCE EFFECT OF HEAT SOURCE TEMPERATURE ON SILICA GEL-WATER ADSORPTION CHILLER(Heat Pump-2)." Proceedings of the International Conference on Power Engineering (ICOPE) 2009.3 (2009): _3–163_—_3–165_. http://dx.doi.org/10.1299/jsmeicope.2009.3._3-163_.

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Bekele, Getachew. "Review on the Effect of Heat Stress on Poultry Production and Productivities." Food Science & Nutrition Technology 6, no. 2 (2021): 1–9. http://dx.doi.org/10.23880/fsnt16000260.

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Heat stress is a situation where too much heat is absorbed by a person, a plant or an animal and causes stress, illness or even death. Therefore, the objective of this review was to compile current knowledge and evidence from literature about the effects of heat stress in poultry production, and productivities. Heat stress is manifested by elevated body temperature, hot, dry skin, lack of sweating and neurological symptoms such as paralysis, headache, vertigo and unconsciousness. Poultry seems to be particularly sensitive to temperature-associated environmental challenges, especially heat stress. In the first days of their life poultry need hot climate (32-38°C), but the optimal temperature decreases rapidly with age by 2.5-3.0°C per week. Birds may use sand baths to dissipate the heat from the body, move to a shaded area or seek a micro-environment that avoids extremely high environmental temperature. Birds rose in an open-sided house at 37°C and humidity level of 50-60% showed signs of panting and wing lifting, elevation of body temperature, lower feed consumption, a higher feed conversion ratio, and lowered body weight gain. In females, heat stress can disrupt the normal status of reproductive hormones at the hypothalamus and ovary leading to reduced systemic levels and functions. Also in males, semen volume, sperm concentration, number of live sperm cells and motility decrease when subjected to heat stress. In egg production, heat stress has a significant harmful impact on body weight, and feed consumption of laying hens at peak production, egg weight, shell weight, shell thickness, and gravity. Both meat type and egg laying chickens respond negatively to high ambient temperatures. Heat stress reduces the relative weights of lymphoid organs like spleen, thymus and cloacae bursa.

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Bekele, Getachew. "Review on the Effect of Heat Stress on Poultry Production and Productivities." Food Science & Nutrition Technology 6, no. 2 (2021): 1–9. http://dx.doi.org/10.23880/fsnt-16000260.

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Heat stress is a situation where too much heat is absorbed by a person, a plant or an animal and causes stress, illness or even death. Therefore, the objective of this review was to compile current knowledge and evidence from literature about the effects of heat stress in poultry production, and productivities. Heat stress is manifested by elevated body temperature, hot, dry skin, lack of sweating and neurological symptoms such as paralysis, headache, vertigo and unconsciousness. Poultry seems to be particularly sensitive to temperature-associated environmental challenges, especially heat stress. In the first days of their life poultry need hot climate (32-38°C), but the optimal temperature decreases rapidly with age by 2.5-3.0°C per week. Birds may use sand baths to dissipate the heat from the body, move to a shaded area or seek a micro-environment that avoids extremely high environmental temperature. Birds rose in an open-sided house at 37°C and humidity level of 50-60% showed signs of panting and wing lifting, elevation of body temperature, lower feed consumption, a higher feed conversion ratio, and lowered body weight gain. In females, heat stress can disrupt the normal status of reproductive hormones at the hypothalamus and ovary leading to reduced systemic levels and functions. Also in males, semen volume, sperm concentration, number of live sperm cells and motility decrease when subjected to heat stress. In egg production, heat stress has a significant harmful impact on body weight, and feed consumption of laying hens at peak production, egg weight, shell weight, shell thickness, and gravity. Both meat type and egg laying chickens respond negatively to high ambient temperatures. Heat stress reduces the relative weights of lymphoid organs like spleen, thymus and cloacae bursa.

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Pretorius, Thea, Gerald K. Bristow, Alan M. Steinman, and Gordon G. Giesbrecht. "Thermal effects of whole head submersion in cold water on nonshivering humans." Journal of Applied Physiology 101, no. 2 (2006): 669–75. http://dx.doi.org/10.1152/japplphysiol.01241.2005.

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This study isolated the effect of whole head submersion in cold water, on surface heat loss and body core cooling, when the confounding effect of shivering heat production was pharmacologically eliminated. Eight healthy male subjects were studied in 17°C water under four conditions: the body was either insulated or uninsulated, with the head either above the water or completely submersed in each body-insulation subcondition. Shivering was abolished with buspirone (30 mg) and meperidine (2.5 mg/kg), and subjects breathed compressed air throughout all trials. Over the first 30 min of immersion, exposure of the head increased core cooling both in the body-insulated conditions (head out: 0.47 ± 0.2°C, head in: 0.77 ± 0.2°C; P < 0.05) and the body-exposed conditions (head out: 0.84 ± 0.2°C and head in: 1.17 ± 0.5°C; P < 0.02). Submersion of the head (7% of the body surface area) in the body-exposed conditions increased total heat loss by only 10%. In both body-exposed and body-insulated conditions, head submersion increased core cooling rate much more (average of 42%) than it increased total heat loss. This may be explained by a redistribution of blood flow in response to stimulation of thermosensitive and/or trigeminal receptors in the scalp, neck and face, where a given amount of heat loss would have a greater cooling effect on a smaller perfused body mass. In 17°C water, the head does not contribute relatively more than the rest of the body to surface heat loss; however, a cold-induced reduction of perfused body mass may allow this small increase in heat loss to cause a relatively larger cooling of the body core.

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Cho, MinSeok, Bumsoo Yoon, Jinsun Kim, Seok-Ho Rhi, and Kibum Kim. "Effect of Heat Pipe Shape on Heat Transfer Performance." Journal of Industrial Science and Technology Institute 35, no. 2 (2021): 39–44. http://dx.doi.org/10.54726/jisti.35.2.7.

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Mahrooghi, Ali, and Mohammad Moghiman. "Effect of nanoparticles on heat transfer in heat exchangers." Ciência e Natura 37 (December 21, 2015): 199. http://dx.doi.org/10.5902/2179460x20848.

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In this paper, forced convection flow and heat transfer of a Al2O3/Water nanofluid have beeninvestigated numerically by single and two phase (volume of fluid) models. Nanofluid flows inside the innertube of the isothermally concentric circular and sinusoidal double tube heat exchangers while hot pure waterflows in the outer tube. The single-phase and two-phase models is used to simulate the nanofluid forcedconvection of 2% and 3% volume concentrations. The renormalization group k-ε model is used to simulateturbulence in ANSYS FLUENT 15.0. Results show that the overall heat transfer coefficient increases withnanoparticle volume concentrations in the heat exchangers. The highest overall heat transfer coefficient rates aredetected, for each concentration and shape, corresponding to the highest flow rate for the sinusoidal tube heatexchanger . The maximum overall heat transfer coefficient enhancement is 220% for the particle volumeconcentration of 3% at the inner tube of concentric sinusoidal double tube heat exchanger corresponding to flowrate =10 LPM. The results reveal that the Al2O3/water pressure drop along the inner tube of circular andsinusoidal double tube heat exchanger increases by about 3% and 5% for volume concentrations of 2% and 3%,respectively, given flow rate compared to the base fluid.Comparison of these results with Rohit S. Khedkar‘spublished experimental data, showed good agreement.

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Chowdhury, Kakali. "MHD Mixed Convective Nanofluid Flow: Effect of Heat Source and Corrugated Boundary." Nanomedicine & Nanotechnology Open Access 8, no. 3 (2023): 1–14. http://dx.doi.org/10.23880/nnoa-16000255.

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The problem of MHD mixed convection is analyzed in a lid driven cavity with corrugated wavy bottom wall filled with Cu-H2 O nanofluid in presence of internal heat source. The top and right walls of the cavity are maintained with a uniform cold temperature whereas the left wall and bottom wavy wall are kept adiabatic. The top wall is moving with a constant velocity upon its lid and a rectangular heat source is placed horizontally inside the cavity. The physical problem is characterized by 2D governing partial differential equations along with proper boundary conditions and are discretized using Galerkin’s finite element formulation. The study is executed by analyzing different ranges of geometrical, physical and nondimensional parameters namely, wave number of wavy surface (0 ≤ ≤ λ 4) , the ratio of heat source height and cavity height 1 3 1 20 a l  ≤ ≤      volume fraction of nanoparticle (0 ≤ ≤ ϕ 0.09) Hartmann number (0 ≤ ≤ Ha 90) and Richardson number (0.1≤ ≤ Ri 10) . The results indicate that heat transfer rate decreases with the increasing value of heat source height and cavity height ratio a L       . It decreases about 9% and 25% with the increasing ratio of a L from 1 20 to 1 10 and 1 5 respectively. It also reveals that heat transfer rate increases with the increasing value of wave number of corrugated wall. At Ri=1 and Ha=0 heat transfer rate increases about 9% and 16% with the increasing value of λ from 0 to 2 and 4 respectively for nanofluid with 6% of nanoparticle. Keywords: MHD; Nanoparticle; Nanofluid

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Wojtas, Krzysztof, Przemysław Cwynar, and Roman Kołacz. "Effect of thermal stress on physiological and blood parameters in merino sheep." Bulletin of the Veterinary Institute in Pulawy 58, no. 2 (2014): 283–88. http://dx.doi.org/10.2478/bvip-2014-0043.

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Abstract Fifteen sheep where placed in climatic chamber and exposed to a high temperature (30°C). Then, the air movement was induced in order to examine its soothing effect on heat stress. The physiological reactions like respiratory and heart rates, as well as the morphologic, biochemical parameters and cortisol levels in blood were examined. It was found that under heat stress conditions, the respiratory rate increased up to 96.43 breaths/min, heart rate up to 107.79 beats/min, and white blood cells count decreased to 9.12 k/μL. The increased level of potassium, chlorine, and calcium was also observed. The increased air movement resulted in thermal stress soothing. A decrease in respiratory rate, heart rate, and cortisol concentration was observed. The study demonstrated that heat stress leads to serious changes in physiological and blood parameters in sheep but this effect can be minimised by air movement.

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Lawton, B. "Effect of Compression and Expansion on Instantaneous Heat Transfer in Reciprocating Internal Combustion Engines." Proceedings of the Institution of Mechanical Engineers, Part A: Power and Process Engineering 201, no. 3 (1987): 175–86. http://dx.doi.org/10.1243/pime_proc_1987_201_022_02.

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Instantaneous heat flux at the surface of a cylinder head in a motored diesel engine has been measured, at various speeds, using a fast-response surface thermocouple. Heat flux during compression was found to be much larger than heat flux during expansion, the maximum heat flux occurred about 8° before top dead centre and there was a significant heat flux even when gas temperature and wall temperature were equal. During expansion, heat flowed from the surface to the gas even though the bulk gas temperature was greater than the surface temperature. These effects are predicted by solutions of the equation of thermal energy and are shown to be related to the volumetric rate of compression or expansion. A simple modification of Annand's equation gives good results and is recommended for general cycle calculations.

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Sullo, Alessio, Guglielmo Brizzi, and Nicola Maffulli. "Serotonin effect on deiodinating activity in the rat." Canadian Journal of Physiology and Pharmacology 81, no. 7 (2003): 747–51. http://dx.doi.org/10.1139/y03-068.

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Serotonin (5-HT) and thyroid hormones are part of a complex system modulating eating behaviour and energy expenditure. 5'-Deiodinase (5'-D) converts the relatively inactive thyroxine (T4) to triiodothyronine (T3), and its activity is an indirect measure of T3 production in peripheral tissues, particularly in the brain, intrascapular brown adipose tissue (IBAT), heart, liver, and kidney. We evaluated the effect of 5-HT on 5'-D activity during basal conditions and after short (30 min) cold exposure (thyroid stimulating hormone stimulation test, TST). 5'-D activity was assessed in the liver, heart, brain, kidney, and IBAT. TST increases 5'-D activity in the brain, heart, and IBAT and decreases it in kidney, leaving it unchanged in the liver. 5-HT alone did not modify 5'-D activity in the organs under study but decreased it in the IBAT, heart, and brain when injected before the TST was administered. Our results confirm the important role of 5-HT in thermoregulation, given its peripheral site of action, in modulating heat production controlling intracellular T3 production. These effects are more evident when heat production is upregulated during cold exposure in organs containing type II 5'-D, such as the brain, heart, and IBAT, which are able to modify their function during conditions that alter energy balance. In conclusion, 5-HT may also act peripherally directly on the thyroid and organs containing type II 5'-D, thus controlling energy expenditure through heat production.Key words: serotonin, deiodinase activity, thyroid hormone, brown adipose tissue, thermogenesis, rat organs.

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Hong, J. T., Y. Yamada, and C. L. Tien. "Effects of Non-Darcian and Nonuniform Porosity on Vertical-Plate Natural Convection in Porous Media." Journal of Heat Transfer 109, no. 2 (1987): 356–62. http://dx.doi.org/10.1115/1.3248088.

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This work examines analytically the effects of non-Darcian and nonuniform permeability conditions on the natural convection from a vertical plate in porous media. The non-Darcian effects, which include the no-slip and inertia effects, decrease the flow and heat transfer rate, while the nonhomogeneity effect enhances the heat transfer. For packed spheres, in particular, the nonhomogeneity in permeability due to the packing of spheres near the solid wall results in a strong flow-channeling effect that significantly increases the heat transfer. The effect of transverse thermal dispersion is also examined. This dispersion effect causes an increase in the heat transfer.

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Rabi, KARAALİ*. "EXERGY ANALYSIS OF HALF-EFFECT ABSORPTION COOLING CYCLES." INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY 5, no. 9 (2016): 405–11. https://doi.org/10.5281/zenodo.154222.

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Absorption cooling cycles are environmental, clean and economically driven cycles. By consuming very small electric power, they can use waste heat or solar energy for cooling. This work presents exergy analysis of a half effect absorption system. A computer program is developed by the author in FORTRAN codes for the thermodynamic properties of lithium bromide-water solutions to use for the exergy analysis. The half effect absorption systems have the advantage of using low temperature heat energy for cooling. The coefficient performance (COP) and the exergetic coefficient performance (ECOP) of the half effect absorption systems are found as 0.45 and 0.24, respectively. For each component the exergy loss is calculated. Most of the irreversibilities are found in the evaporator and in the absorbers. It is concluded that the half effect absorption systems is the best for cooling driven by low temperature heat energy and the performance of the evaporator and the absorbers is very important for the cycle.

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Rajan, R. Anju, S. C. Edwin S.C. Edwin, K. Rajendran K. Rajendran, N. Murali N. Murali, and R. Kumar Pramod. "Effect of Heat Stress on Internal Organs of Four Chicken Varieties." International Journal of Scientific Research 3, no. 8 (2012): 467–68. http://dx.doi.org/10.15373/22778179/august2014/148.

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Tho, Trinh Tien, Dang Van Hai, Dao Van Duong, Nguyen Minh Phu, and Momchil Vassilev. "Numerical Simulation of Human Head Temperature: New Data and Comparison." Journal of Advanced Research in Numerical Heat Transfer 30, no. 1 (2025): 108–19. https://doi.org/10.37934/arnht.30.1.108119.

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Controlling the temperature of the human head is vital for health and performance. Excessive heat can lead to conditions such as heat exhaustion and heatstroke. Since the head is a key area for dissipating heat, managing its temperature helps prevent overheating and related health issues. In this study, the bio-heat governing equation was solved using the finite difference method. The effects of ambient temperature (-10 to 40°C), air velocity (0 to 3 m/s), cerebral blood flow (0.1 to 9.45 kg/m3 s), and skin blood flow (0.1 to 3.2 kg/m3 s) on the temperature distribution in the head were investigated. The results showed good agreement with published data. The effect of cerebral blood flow was significant on brain temperature. While other parameters only changed the temperature of the outer layers of the head, the brain temperature remained stable. The spherical assumption of the head geometry used in the current numerical heat transfer analysis is a common simplification to reduce computational complexity. However, this assumption introduces certain limitations and can impact the generalizability and accuracy of the results, particularly when applied to real human head geometries.

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Krisdiyanto, Krisdiyanto, Rahmad Kuncoro Adi, Sudarisman Sudarisman, and Sinin Bin Hamdan. "An analysis of tube thickness effect on shell and tube heat exchanger." Eastern-European Journal of Enterprise Technologies 1, no. 8 (109) (2021): 25–35. http://dx.doi.org/10.15587/1729-4061.2021.225334.

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Heat exchangers are important equipment for the process of placing heat. The most widely used type of heat exchanger is shell and tube. This type is widely used because of its simple and easy design. Design of shell and tube heat exchangers is done by the side or shell variations to get the desired performance. Therefore, research is conducted to study the effect of tube thickness on heat transfer, pressure drop, and stress that occurs in the shell and tube heat exchanger so that the optimal tube thickness is obtained. In this research, the activities carried out are the design of heat exchangers for the production of oxygen with a capacity of 30 tons/day. The standard used in this study is the 9th edition heat exchanger design guidance document compiled by the Tubular Exchanger Manufacturer Association (TEMA). Analysis of the tube thickness effect on heat transfer, pressure drop, and stress was carried out using the SimScale platform. The effect of variations in tube thickness on heat transfer is that the thicker the tube, the lower the heat transfer effectiveness. The highest value of the heat exchanger effectiveness is 0.969 at the tube thickness variation of 0.5 mm. The lowest value of the heat exchanger effectiveness is 0.931 at the tube thickness variation of 1.5 mm. The effect of variations in tube thickness on pressure drop is that the thicker the tube, the higher the pressure drop. The highest value of pressure drop is in the variation in tube thickness of 1.5 mm, 321 Pa. The lowest value of drop pressure is in the variation of 0.5 mm tube thickness, which is 203 Pa. The thickness of the tube also increases the maximum stress on the components of the shell, head, tubesheet, baffle, and saddle, but the value is fluctuating

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Krisdiyanto, Krisdiyanto, Kuncoro Adi Rahmad, Sudarisman Sudarisman, and Bin Hamdan Sinin. "An analysis of tube thickness effect on shell and tube heat exchanger." Eastern-European Journal of Enterprise Technologies 1, no. 8(109) (2021): 25–35. https://doi.org/10.15587/1729-4061.2021.225334.

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Heat exchangers are important equipment for the process of placing heat. The most widely used type of heat exchanger is shell and tube. This type is widely used because of its simple and easy design. Design of shell and tube heat exchangers is done by the side or shell variations to get the desired performance. Therefore, research is conducted to study the effect of tube thickness on heat transfer, pressure drop, and stress that occurs in the shell and tube heat exchanger so that the optimal tube thickness is obtained. In this research, the activities carried out are the design of heat exchangers for the production of oxygen with a capacity of 30 tons/day. The standard used in this study is the 9<sup>th</sup> edition heat exchanger design guidance document compiled by the Tubular Exchanger Manufacturer Association (TEMA). Analysis of the tube thickness effect on heat transfer, pressure drop, and stress was carried out using the SimScale platform. The effect of variations in tube thickness on heat transfer is that the thicker the tube, the lower the heat transfer effectiveness. The highest value of the heat exchanger effectiveness is 0.969 at the tube thickness variation of 0.5 mm. The lowest value of the heat exchanger effectiveness is 0.931 at the tube thickness variation of 1.5 mm. The effect of variations in tube thickness on pressure drop is that the thicker the tube, the higher the pressure drop. The highest value of pressure drop is in the variation in tube thickness of 1.5 mm, 321 Pa. The lowest value of drop pressure is in the variation of 0.5 mm tube thickness, which is 203 Pa. The thickness of the tube also increases the maximum stress on the components of the shell, head, tubesheet, baffle, and saddle, but the value is fluctuating

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Currie, J. M., and D. J. Adamson. "The thrombolytic effect of heat." Postgraduate Medical Journal 69, no. 807 (1993): 55–56. http://dx.doi.org/10.1136/pgmj.69.807.55.

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McCormick, P. G. "Effect of heat recovery on the performance of a shape-memory effect heat engine." Applied Energy 27, no. 4 (1987): 289–304. http://dx.doi.org/10.1016/0306-2619(87)90023-7.

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Liu, Xiao, Yuan Fu Cao, and Ti En Zhang. "Experimental Study on Boiling Heat Transfer in Cylinder Head Jacket." Advanced Materials Research 433-440 (January 2012): 18–23. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.18.

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Experiments of the valve bridge are carried out and the boiling states are investigated, to study the boiling heat transfer in cylinder head jacket. The effects of inlet flow rate and temperature on boiling heat flux are analyzed, as well as the thickness of fire deck. The results show that the inlet velocity has little effect on the velocity in valve bridge zone, even the velocity in the valve bridge zone can strongly affect on boiling heat transfer. The results can offer references to practical application in power-enhanced diesel engine.

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Zhao, Yu, and Guangyu Zhang. "Thermal Effect of the Back Radiation from Disk to Head after Laser Heating in HAMR." Applied Sciences 13, no. 17 (2023): 9730. http://dx.doi.org/10.3390/app13179730.

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In a heat-assisted magnetic recording, the thermal effect of the head/disk interface has an important influence on the stability of the recording data. In this paper, we will discuss the thermal radiation from the disk, more specifically, the magnetic recording layer, which is at high temperature after laser heating, to the magnetic head, which is at room temperature. The radiative heat flux can be represented by the Poynting vector. In the near-field band, an effective way to obtain the electromagnetic fields is to solve the Maxwell’s equations combined with fluctuational electrodynamics. The near-field back radiation between specific head and disk material is calculated by the fluctuation-volume-current method. The radiative heat energy will induce the thermal deformation of the magnetic head, which will be discussed by the simulation, laying the foundation for adjusting and controlling the flying status.

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Darkwa, J., W. Su, and D. H. C. Chow. "Heat dissipation effect on a borehole heat exchanger coupled with a heat pump." Applied Thermal Engineering 60, no. 1-2 (2013): 234–41. http://dx.doi.org/10.1016/j.applthermaleng.2013.07.011.

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Wang, Yi, Tiejun Lu, Xianglei Liu, Adriano Sciacovelli, and Yongliang Li. "Heat Transfer of Near Pseudocritical Nitrogen in Helically Coiled Tube for Cryogenic Energy Storage." Energies 15, no. 8 (2022): 2752. http://dx.doi.org/10.3390/en15082752.

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This paper investigates the cryogenic heat transfer phenomena of nitrogen flowing in helically coiled tubes under the combined effects of pseudocritical conditions, buoyancy, and coil curvature. The ultimate goal was to design optimum heat exchangers for liquid air energy storage. Local heat transfer coefficients were evaluated peripherally across tube cross sections. The pressure, mass flux, and heat flux effects on the heat transfer were examined. The dual effect of buoyancy and coil curvature on heat transfer coefficients was interpreted via a dimensionless number Ψ, which denotes a ratio between the two effects. Results reveal that the heat transfer coefficients increase with increasing mass flux but decreasing pressure and heat flux. The buoyancy effect dominates the heat transfer at fluid temperatures below the pseudocritical temperature (e.g., −146.3 °C at 35 bar), while the coil curvature-induced centrifugal effect dominates at higher temperatures. The heat transfer coefficients for the helical coil were approximately 13% lower compared with those in straight tube at fluid temperatures below the pseudocritical temperature, but their difference shrinks (<±6%) at higher temperatures. The reason is that the benefits of coil curvature and improved turbulent mixing on heat transfer are counteracted by the thermophysical property variation and buoyancy effect.

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Md., Saddam Hussiain, Punaykanti S., Ranjan Panda Rashmi, and Mohanta Dillip. "Effect of Heat Treatment in Low Carbon Steel." International Journal of Engineering and Management Research 8, no. 2 (2018): 87–90. https://doi.org/10.5281/zenodo.3361972.

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Low carbon steel is easily available and cheap having all material properties that are acceptable for many applications. Heat treatment on low carbon steel is to improve ductility, to improve toughness, strength, hardness and tensile strength and to relive internal stress developed in the material. Here basically the experiment of harness and ultimate tensile strength is done to get idea about heat treated low carbon steel, which has extensive uses in all industrial and scientific fields

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Li, Peng. "Analysis of the Impact of Land Use Planning on Urban Heat Island Effect." Frontiers in Science and Engineering 4, no. 2 (2024): 42–48. http://dx.doi.org/10.54691/az33z083.

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This paper reviews the research progress and prospects of urban heat island effect, and systematically analyzes and evaluates the formation mechanism, influencing factors and mitigation measures of urban heat island effect from three aspects: observation, simulation and mitigation. Urban heat island effect is a typical environmental problem in the process of urbanization, which has important impacts on the climate, ecology, energy, health and other aspects of the city. The research of urban heat island effect has important theoretical significance and practical value, and provides scientific basis and guidance for the sustainable development of the city.The paper summarizes the main strategies of land use planning optimization for heat island effect, including increasing green space coverage, improving surface albedo, optimizing urban morphology and structure, etc., analyzes their mechanism and applicability conditions, evaluates their effects and influencing factors, and discusses their applicability and sustainability. The strategies of land use planning optimization for heat island effect need to select and combine the appropriate strategies according to the specific situation and goal of the city, so as to achieve the best effect. At the same time, the strategies of land use planning optimization for heat island effect need to coordinate and integrate with other urban planning and management objectives and measures, so as to avoid conflicts and negative effects, and improve the applicability and sustainability of land use planning optimization for heat island effect.

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Mustafvi, Sajid Ali, Nadeem Yousaf, Zainab Amjad, Tahir Ahamd Munir, Syed Shoiab Shah, and Rehan Majeed. "HEAT RELATED ILLNESSES." Professional Medical Journal 22, no. 05 (2015): 546–53. http://dx.doi.org/10.29309/tpmj/2015.22.05.1264.

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Objective: To study the adaptive strategies from harmful effect of heat waveon an urban, educated, well to do subjects for a period of May to July 2014.Data Source:250 selected young students of RIHS. Design of Study: Descriptive Study. Setting: RawalInstitute of Health Sciences, Islamabad. Period: March – July 2014. Method: A questionnairewas circulated among the students of Rawal Institute of Health Sciences Islamabad regardingeffects of heat and measures taken to combat its effects. Results: A total of 250 urban studentswith mean age of 19.77±1.10 years were inducted in the study, having resources to face theextreme heat. A significant number of female non boarder students (p=0.000), wearing cottonclothes (p=0.000) having fair skin (p=0.000) and using air condition at homes (p=0.000) werenot acclimatized to heat waves still have headache and anxiety. A great percent of students didnot complaint of headache, heat exhaustion, heat cramp or syncope, except mild sweating,effect on studies. A great percentage (>65%) of students complained of malaise, nauseavomiting. Male students showed increase thirst than female, while anxiety state was noticedmore in female than male students. Conclusion: The use of cotton clothing, daily bathing,increased water intake and use of air conditioner minimized the severe adverse effects likeheat exhaustion, heat syncope, and heat stroke, although the minor effects like skin tanning,disturbed sleep, anxiety and adverse effects on studies cannot be avoided in heat wave season.

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BRESTER, A. E., V. I. ZHUKOV, D. A. SHVETSOV, and A. N. PAVLENKO. "EFFECT OF LIQUID LAYER HEIGHT ON HEAT TRANSFER DURING EVAPORATION/BOILING UNDER LOW-PRESSURE CONDITIONS." Herald of Technological University 27, no. 10 (2024): 74–78. https://doi.org/10.55421/1998-7072_2024_27_10_74.

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The paper presents experimental data on the effect of the height of the horizontal layer of liquid on heat transfer obtained in an experimental setup, which is a thermosiphon. The installation is a cylindrical apparatus with a diameter of 120 mm and height of 300 mm made of steel 12Х18Н10Т. N-dodecane was used as a working fluid. The pressure in the working chamber was varied in the range from 33 Pa to 20 kPa, and the height of the liquid layer from 1.4 mm to 40 mm. It was found that no bubble boiling was observed in the pressure range less than 10 kPa, and increasing the height of the liquid layer resulted in an increase in the temperature head. It was also obtained that with increasing the height of the liquid layer, the heat transfer coefficient increases and has a maximum at a height of the liquid layer of 2.5 mm, when the heat exchange is carried out mainly due to the evaporative component. With further increase in the height of the liquid layer the heat transfer coefficient decreases, and for heights of the liquid layer more than 20 mm the change of the heat transfer coefficient practically does not occur. It is obtained that at pressures over 10 kPa, when bubble boiling is observed, the temperature head decreases with increasing height of the liquid layer and reaches a minimum at a layer height of 10 mm. Further increase in the height of the liquid layer leads to a weak increase in the temperature head. The heat transfer coefficient with increasing height of the liquid layer increases and reaches a maximum at 10 mm, further increase in the height of the liquid layer leads to a slight decrease in the heat transfer coefficient.

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Zhao, Qijin, Xianghua Bai, Baoquan Mao, and Zili Liao. "Flow and heat transfer characteristics of conductive gases in circular tubes under applied magnetic fields with different orientations." Physics of Fluids 34, no. 3 (2022): 035112. http://dx.doi.org/10.1063/5.0085009.

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Controlling the flow and heat transfer characteristics of conductive gases in circular tubes by means of applied magnetic fields is of great significance in various applications. However, the specific effects of magnetic fields with different orientations on these flow and heat transfer characteristics remain poorly understood. This paper addresses this issue by applying numerical calculations for evaluating the effect of magnetic fields (MFs) with different magnitudes defined according to the Hartmann number ( Ha) ranging from 0 to 740 and orientation, including transverse (TMFs), axial (AMFs), and radial (RMFs) on the flow and heat transfer characteristics of high-temperature conductive gas flows with Reynolds numbers ( Re) ranging from 9612 to 32 040. The results demonstrate that applied TMFs have anisotropic effects on the flow and heat transfer of conductive gases, while the effects of applied AMFs and RMFs are isotropic. Applied AMFs have little effect on the heat transfer characteristics of conductive gases, while applied TMF and RMF conditions suppress heat transfer at the tube wall, and the suppression effect of RMFs is stronger. Moreover, the heat transfer suppression effect of applied TMFs and RMFs first increases and then decreases with increasing Ha for a constant Re, and the value of Ha required to achieve the optimal heat transfer suppression effect increases with increasing Re. In addition, the transition gradient of the magnetic field directly outside of the applied magnetic field region causes the accumulation of Joule heat and therefore detracts significantly from the heat transfer suppression effect of TMFs and RMFs.

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Shin, Byung-Hyun, Jinsurang Lim, Doo-In Kim, et al. "Effect of Heat Treatment Duration on the Recrystallization and Electrochemical Properties of Cold-Rolled Cantor-Type High-Entropy Alloy." Materials 18, no. 10 (2025): 2298. https://doi.org/10.3390/ma18102298.

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High-entropy alloys (HEAs), such as the Cantor alloy, are considered for various structural applications owing to their excellent corrosion resistance and high strength at low temperatures, typically below −70 °C, including cryogenic conditions. However, during metalworking, introducing stresses and grain refinement can reduce the corrosion resistance of HEAs. Recrystallization heat treatment relieves these stresses and homogenizes the grain structure, thereby restoring their corrosion resistance and physical properties. However, inadequate heat treatment can result in a microstructure in which coarse and refined grains coexist; thus, the corrosion resistance is diminished and the physical properties are compromised. Therefore, a proper heat treatment is essential for achieving the desired corrosion resistance and mechanical properties of HEAs. In this study, a cold-rolled high-entropy Cantor alloy was subjected to heat treatment for various durations, and the conditions were analyzed. The microstructure and electrochemical behavior were examined. The results indicated that the grains coarsened after a heat treatment time of 5 min and the residual stresses decreased for 15 min. The potential increased from −0.20 to −0.09 V, whereas the resistance of the passive layer increased from 39 to 56 kΩ. These findings confirm that in the Cantor alloy, residual stress reduction and recrystallization begin after 5 min of heat treatment at 1100 °C, which contributes to the recovery of corrosion resistance. The corrosion resistance of the Cantor alloy can be effectively controlled through heat treatment. This underscores the importance of optimizing the heat treatment process in the manufacturing of Cantor alloys.

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Rana, MS, MA Hashem, S. Akhter, M. Habibullah, MH Islam, and RC Biswas. "Effect of heat stress on carcass and meat quality of indigenous sheep of Bangladesh." Bangladesh Journal of Animal Science 43, no. 2 (2014): 147–53. http://dx.doi.org/10.3329/bjas.v43i2.20717.

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The research was conducted to study the effect of heat stress on carcass characteristics and meat quality in indigenous sheep. Nine sheep were divided into three groups which were almost similar in age, sex and weight. Three groups were divided as zero hour (T0), four hours (T4) and eight hours (T8) heat exposure to direct sunlight. During experimental period temperaturehumidity index (THI) value was calculated as 27.09 which indicated T4 and T8 groups were subjected to heat stress condition for at least four hours and eight hours respectively every day. Slaughter weight, body length and heart girth had no significant difference among the treatment groups. Dry matter, ash and ether extract had no significant difference (p>0.05) among the treatment groups but crude protein were increased with the increase of heat stress from T0 to T8 group (p<0.05). Drip loss was increased (p<0.05) in non-exposure group than treated groups but there is no significant result (p>0.05) found in pH and cooking loss. Carcass weight and eye muscle area had no significant difference (p>0.05) among the treatment groups but dressing percentage was decreased with the increase of time in heat treated groups (p<0.01). Significant difference (p<0.05) were found in weight of heart, kidney, lung + trachea and pluck between control and heat treated groups. The significant difference (p>0.05) in empty gut was found in gut with content and gut fill in heat treated groups. It can be concluded that heat stress had significant changes on carcass characteristics and meat quality of indigenous sheep.DOI: http://dx.doi.org/10.3329/bjas.v43i2.20717 Bang. J. Anim. Sci. 2014. 43 (2): 147-153

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Muzammil, Mohammad, Abid Ali Khan, and Faisal Hasan. "Effect of noise, heat stress and exposure duration on operators in a die casting operation." Occupational Ergonomics 7, no. 4 (2008): 233–45. http://dx.doi.org/10.3233/oer-2007-7402.

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The present study was designed to investigate the effect of noise and heat stress on operators of various age groups performing die casting operation at varying exposure durations. The independent variables selected were age of operator (20–25, 25–30 and 30–35 years), equivalent levels of noise (90, 95 and 100 dB(A)), heat stress (35, 40 and 45°C wet bulb globe temperature) and exposure duration (5, 10 and 15 minutes) while the dependent variable was heart rate measured with the help of pulse-oximeter. The results of the study showed that the main effects of heat stress, equivalent noise level, age group and the interaction between levels of equivalent noise and exposure duration were all had a statistically significant effect on operators performing the task. The three way interaction of age group, subject and equivalent noise level was also observed to be statistically significant.

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Aharoni, Y., A. Brosh, and E. Ezra. "Effects of heat load and photoperiod on milk yield and composition in three dairy herds in Israel." Animal Science 69, no. 1 (1999): 37–47. http://dx.doi.org/10.1017/s1357729800051079.

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AbstractEffects of heat load and of photoperiod on lactation performance were evaluated using milk test data of three Israeli Holstein herds over a period of 3 years, from 1994 to 1996. All together 2209 cows, with 28029 milk records, were included. Photoperiod effects were examined as associated with day length and daily changes in day length and heat load index was formulated as a function of the seasonal day and night ambient temperatures, to account for the heat load effect. The regression model included effects of cow, herd, year, lactation number and days in milk in addition to the seasonal effects. The dependent variables were milk yield and fat, protein and lactose concentrations. Milk yield was affected by both photoperiod and heat load, with the peak photoperiod effect in May and amplitude of 3·1 (s.d. 0·9) kg/day and negative heat load effect of-1-8 (s.d. 0·4) kg/day at its peak. Protein concentration was affected by photoperiod, with the peak effect in January (amplitude of 1·7 (s.e. 0·5) g/kg) but not by heat load (-0-2 (s.d. 0·6) glkg). Fat concentration was affected primarily by heat load (-3-4 (s.d. 0·7) g/kg), with a photoperiod effect which peaked in October (amplitude of 1·8 (s.d. 0·8) g/kg). Lactose concentration was affected by both environmental factors to a lesser extent (photoperiod amplitude of 0·6 (s.d. 0·2) g/kg and heat load effect of-0-03 (s.d. 0·16) g/kg). Comparison of the predicted seasonal effects on milk yield and composition with the annual fluctuation in the national herd showed a good match of the predicted effects with the national observations. It is concluded that while heat load relief may be beneficial, manipulation of the photoperiod may induce adverse effects on milk yield and composition.

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Journal articles on the topic 'Effect of heat'

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