Academic literature on the topic 'Temperature gradient and Stress distribution'
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Journal articles on the topic "Temperature gradient and Stress distribution"
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Hu, Chang Bin, Mu Lu Du, and Li Juan Wang. "Research of Built-In Temperature and Zero Stress Temperature of Cement Concrete Pavement at Early Ages." Advanced Materials Research 857 (December 2013): 248–55. http://dx.doi.org/10.4028/www.scientific.net/amr.857.248.
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Based on field tests and numerical simulation methods, distribution characteristics of early-age built-in temperature of cement concrete pavement constructed in different seasons and pouring time were analyzed firstly. Then considering effect of creep, characteristics of early-age zero stress temperature in cement concrete that built-in temperature of cement concrete pavement constructed in different seasons and pouring time has a great difference. The distributions of built-in temperature along the thickness present nonlinear obviously, and they have four typical types: concave and positive gradient type, concave negative gradient type, convex positive gradient type and convex negative gradient type. Zero stress temperature gradient shows prominently developing process compared with built-in temperature of slab at different ages by the effect of creep. Zero stress temperature of slab poured on am7:00 in summer firstly increase and then decline. Besides, the positive gradient change to negative gradient gradually, and the gradient of zero stress temperature trend to decrease. At last, it is recommended to calculate zero stress temperature of slab consideration of base temperature and the nonlinear distributions characteristics, and the combined effect of creep and age.
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Wang, Da, Benkun Tan, Xie Wang, and Zhenhao Zhang. "Experimental study and numerical simulation of temperature gradient effect for steel-concrete composite bridge deck." Measurement and Control 54, no. 5-6 (2021): 681–91. http://dx.doi.org/10.1177/00202940211007166.
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The temperature distribution of the bridge and its thermal effect has always been an important issue for researchers. To investigate the temperature distribution and thermal stress in the steel-concrete composite bridge deck, a 1:4 ratio temperature gradient effect experimental study was carried out in this paper. First, a set of experimental equipment for laboratory temperature gradient loading was designed based on the principle of temperature gradient caused by solar radiation, the temperature gradient obtained from the measurements were compared with the specifications and verified by the FE method. Next, the loading of the steel-concrete composite deck at different temperatures was performed. The thermal stress response and change trend of the simply supported and continuously constrained boundary conditions under different temperature loads were analyzed. The experimental results show that the vertical temperature of steel-concrete composite bridge deck is nonlinear, which is consistent with the temperature gradient trend of specifications. The vertical temperature gradient has a great influence on the steel-concrete composite bridge deck under different constraints, and the extreme stress of concrete slab and steel beam is almost linear with the temperature gradient. Finally, some suggestions for steel-concrete composite deck design were provided based on the research results.
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Zheng, Zhi Jun, Xiao Kai Wang, and Ji Lin Yu. "Mass Impact of Density-Graded Cellular Metals in a Temperature Field." Applied Mechanics and Materials 566 (June 2014): 599–604. http://dx.doi.org/10.4028/www.scientific.net/amm.566.599.
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We consider the problem of a density-graded cellular rod in a temperature gradient field axially subjected to a mass impact. Two-dimensional cell-based finite element models and one-dimensional shock models are employed to explore the mechanisms of deformation and wave propagation. The yield stress distribution in a cellular specimen depends on both the density gradient field and the temperature gradient field. The stress distribution and the yield stress distribution are analyzed. For the increasing yield stress along the impact direction, one shock front propagates from the proximal end to the distal end of the specimen. For the decreasing yield stress along the impact direction, two shock fronts propagate in opposite directions and the one close to the proximal end ceases at a particular time. The predicted stresses of the extended shock models are compared well with the numerical results.
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Zhao, Ya Ding, Xue Ying Li, and Hong Yang Liu. "Simulation and Analysis of the Thermal Stress in Concrete under Temperature Fluctuation Condition." Advanced Materials Research 168-170 (December 2010): 1957–60. http://dx.doi.org/10.4028/www.scientific.net/amr.168-170.1957.
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The temperature field distribution and thermal stress distribution in concrete has been studied by finite elements method to establish the relationship between the thermal stress and the temperature in this paper. The results show that the maximum thermal gradient and the maximum thermal stress in the concrete appears on the direction of greater structural dimension, and the thermal stress value is positively correlated with thermal gradient or saying temperature difference and elastic modulus, and is negatively correlated with the water content and air content.
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Yao, Lei. "Influence of Cooling Rate on Crack Growth and Stress Distribution in Die Steel under Thermal Cycles." International Journal of Mechanical and Electrical Engineering 4, no. 2 (2024): 67–72. https://doi.org/10.62051/ijmee.v4n2.09.
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Die casting molds are prone to thermal fatigue under high-temperature and high-pressure cycles, which significantly affects their service life. In this study, a three-dimensional numerical simulation method is employed to analyze the temperature field, stress field, and crack development process of the mold under different cooling cycles. The results show that shorter cooling cycles (15s, 30s) lead to larger temperature gradients and stress concentrations within the mold, thereby accelerating crack initiation and propagation. In contrast, longer cooling cycles (70s) help to reduce the temperature gradient and stress fluctuations, which in turn slows down crack propagation and effectively extends the mold's service life.
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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 minΔTmax(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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Yang, Guang, Wei Wang, Lan Yun Qin, and Xing Lang Wang. "Numerical Simulation Temperature Field of Laser Cladding Titanium Alloy." Applied Mechanics and Materials 117-119 (October 2011): 1633–37. http://dx.doi.org/10.4028/www.scientific.net/amm.117-119.1633.
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Abstract: In order to control the thermal stress of cladding, a numerical simulation of temperature field during multi-track & multi-layer laser metal deposition (LMD) process is developed with ABAQUS based on “element birth and death” technology of FEM. The dynamic variances of temperature field and stress field of forming process are calculated with the energy compensation of interaction between molten pool-powder. The temperature field, temperature gradient, thermal stress field and distribution of residual stress are obtained. The results indicate that although the nodes on different layers are activated at different time, their temperature variations are similar. The temperature gradients of samples are larger near the molten pool area and mainly along z-direction.
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Aniekan, Essienubong Ikpe Michael Okon Bassey. "Modelling and Simulation of Transient Thermal Stress Distribution across AISI 1018 Flat Plates at Variable Welding Temperature Regime." Journal of Materials Engineering, Structures and Computation 2, no. 3 (2023): 1–22. https://doi.org/10.5281/zenodo.8297860.
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<em>In recent times, failure in structural components has been attributed to a lack of improper understanding of material behaviour under welding temperature, during which thermally induced stresses are trapped (residual stress) within the weldment. This study investigated the effects of variable Tungsten Inert Gas (TIG) welding temperature across AISI 1018 flat plates concerning thermal stress distribution using experimental and Finite Element Method at welding temperatures ranging from 6800-9600<sup>o</sup>F. Thermally-induced stresses of 4244.373 and 4345.894 MPa were obtained from both FEM and Experimental process at a welding temperature of 680<sup>o</sup>F while the thermally induced stress values at a higher welding temperature of 9600<sup>o</sup>F for FEM and experimental process were obtained as 10786.858 and 12124.269 MPa. The study revealed a significant correlation established between the experimentally induced thermal stress distribution and the FEM-induced thermal stress distribution. Moreover, thermally induced stresses were observed to increase as the welding temperature also increased and vice versa. Hence, the FEM approach employed in the study can be adopted as a novel technique for modelling, prediction and control of welding temperature to prevent intense welding heat from translating into detrimental defects due to creep mechanism (thermal loading temperature on material geometry), which may result in untimely failure of component materials in welding-related applications. </em>
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Jameel, Adnan N., Nabeel K. Abid Al-Sahib, and Osama F. Abd Al Latteef. "RESIDUAL STRESS DISTRIBUTION FOR A SINGLE PASS WELD IN PIPE." Journal of Engineering 16, no. 01 (2010): 4618–30. http://dx.doi.org/10.31026/j.eng.2010.01.18.
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Heat input due to the welding of mild steel pipe causes a temperature gradient in the parent metal. After welding and temperature cooling down, residual stresses appear around welding zone which reduces the weld strength. Residual stresses are a result of the temperature gradient and the dependency of material properties on the temperature, such as yield strength, elasticity modulus, and thermal expansion coefficient.In this study, a typical flat joint of a single pass weld in a thin pipe was studied analytically and numerically. Analytical approach is performed by exploring a simple method to calculate the magnitude of residual stress in terms of the weld shrinkage behavior. Numerical analysis is performed by applying non-linear transient heat transfer analysis using welding parameters, such as heat generation, free or force convection with ambient, are performed using a general purpose FE package ANSYS 8.0 in order to obtain the temperature distribution in the welded parts. A non-linear thermal-elastic-plastic stress analysis is then performed using the same package to predict the stress fields during and after welding.
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Koizumi, M., and M. Niino. "Overview of FGM Research in Japan." MRS Bulletin 20, no. 1 (1995): 19–21. http://dx.doi.org/10.1557/s0883769400048867.
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Space planes require high-performance heat-resistant materials which can withstand ultrahigh temperatures and extremely large temperature gradients. To meet these needs, functionally gradient materials (FGMs) were proposed about 10 years ago in Japan.Figure 1 shows a conceptual diagram of functionally gradient materials, taking into account the relaxation of thermal stress. For the surface that contacts high-temperature gases at thousands of degrees, ceramics are used to provide adequate heat resistance. For the surface that provides cooling, metallic materials are used to furnish the necessary thermal conductivity and mechanical strength. In addition, the composition of these materials is formulated to provide optimum distribution of composition, structure, and porosity to effectively relax thermal stress.Since fiscal 1987, an R&D project entitled “Research on Fundamental Techniques to Develop Functionally Gradient Materials for Relaxation of Thermal Stress,” which aimed to develop ultra heat-resistant materials, had been carried out with special coordination funds from the Science and Technology Agency. The five-year project had two phases; Phase I was carried out from 1987 to 1989, and Phase II from 1990 to 1991.
Dissertations / Theses on the topic "Temperature gradient and Stress distribution"
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Meri, Tony Carlos. "Temperature and thermal stress distribution in concrete arch dams in operation." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/11420.
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The temperature field of concrete dams in operational stages is dominantly influenced by variations in environmental seasonal temperature and climatic conditions. Cyclic seasonal temperature and associated thermally induced stresses have been found to contribute significantly to long term degradation of strength and stiffness of concrete dams raising concerns about their durability (Leger et al. 1993). In this study, a critical review of the current state-of-the-art of temperature models for determining temperature distribution including the main environmental parameters influencing the temperature distribution for concrete dams in operation has been undertaken. It is found that, the heat flow in the concrete dams currently is approximated as conduction only and the classical Fourier heat conduction models are adopted as the governing equations to define heat flow mechanisms in the dam. The solution to Fourier heat models is accurately achieved through the finite element analysis using finite element models of the dam to the determine the temperature field.
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Akther, S. M. Lovely. "Effects of water stress on Alnus glutinosa populations across the species distribution range." Master's thesis, ISA, 2019. http://hdl.handle.net/10400.5/19572.
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Mestrado em Gestão da Floresta e dos Recursos Naturais no Mediterrâneo (MedFor) - Instituto Superior de Agronomia<br>Alnus glutinosa (Black alder) is paramount species in the riparian ecosystem for supporting ecosystem functioning and the services it provides. This species is declining in an alarming rate which is a prominent threat to devastate native priority forests across Europe, so understanding population responses to environmental change is key for its proper management. In this study, we characterized vegetative phenology and investigated morphological, structural and physiological responses to imposed drought across five populations from countries ranging the species distribution limits (Sweden, Italy, Spain, Portugal, and Morocco). First, we registered 5 stages of budburst of the 120 seedlings of alder (24 by population) in open space. Then, we established a greenhouse experiment where we imposed progressive (Field capacity-FC, 75%FC, 50%FC and 25%FC) water stress (17.06.2019 to 01.08.2019) on 40 seedlings (S), keeping 40 at field capacity, as control until the end of experiment (CE). During 45 days, we performed physiological and morphological measurement at different percentages of FC to compare treatments and populations. Destructive harvest was performed on 40 seedlings (from the total 120) at the onset of the experiment (CO), and then, at the end of the experiment control (CE) and stress (S) seedlings were also destroyed to analyze the structural and functional responses of alder among CE, S and CO and also to compare the variations among populations. We found significant differences among populations on the number of days to reach each phenological stage where northern populations displayed delayed budburst than the southern. As a result of imposed drought, growth and development of A. glutinosa was generally reduced under water restrictions compared to control plants, yet none of the parameters reflected severe plant stress. Conversely, we observed that several of the studied parameters were significantly different among the studied populations likely reflecting intraspecific diversity and environmental conditions<br>N/A
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Goulding, A. "Small fatigue crack growth in a near alpha titanium alloy : crack closure, stress gradient and temperature considerations." Thesis, Swansea University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637082.
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The effect of fatigue crack closure in IMI 829 has been addressed for cracks growing from plain surfaces and under the influence of a stress concentration. Several test-piece configurations were employed, incuding thick and thin section double edge notches and standard corner crack (CC) geometries. All types incorporated an ultra fine corner slit to bias the crack initiation site. A thin double edge notch (DEN) specimen with a through section starter slit was also tested. Crack closure loads were measured using direct current potential drop (PD) and replica techniques. The primary closure mechanism was found to be a plasticity induced closure. The results indicate the dominance of surface effects. They also permit near tip and wake related closure effects to be resolved. At the higher stresses, notch root plasticity in the thick DEN dominates closure. At lower stresses where elastic conditions prevail, the results were comparable to those found in the plain CC specimen. Much work was carried out to characterise closure of part-through and through thickness cracks in the thin section notch. The transition between the two crack types invoked a complex closure response. A secondary closure mechanism was also identified, for all specimen types. This was roughness induced closure. On the basis of the PD measurements, an effective ΔK was derived which improved correlation of data over the range of stress levels and R values tested. At room temperature, crack lengths were measured using the above PD system and an existing photomicroscopic arrangement. A study of crack shape morphology was carried out using optical and SEM techniques. The observed complex stress and crack length dependency of shape development in thick notch specimens at higher stresses, was explained on the basis of enhanced plasticity induced closure in the notch root. Other deviations from expected shape characteristics, could be rationalised in terms of microstructural interactions.
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Korfel, Chelsea Anne. "Distribution and environmental correlates between amphibians and the fungal pathogen, Batrachochytrium dendrobatidis." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1350573649.
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Yesilyurt, Gokhan. "Numerical simulation of flow distribution for pebble bed high temperature gas cooled reactors." Texas A&M University, 2004. http://hdl.handle.net/1969.1/372.
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The premise of the work presented here is to use a common analytical tool,
Computational Fluid dynamics (CFD), along with a difference turbulence models. Eddy
viscosity models as well as state-of-the-art Large Eddy Simulation (LES) were used to
study the flow past bluff bodies. A suitable CFD code (CFX5.6b) was selected and
implemented.
Simulation of turbulent transport for the gas through the gaps of the randomly
distributed spherical fuel elements (pebbles) was performed. Although there are a
number of numerical studies () on flows around spherical bodies, none of them use the
necessary turbulence models that are required to simulate flow where strong separation
exists. With the development of high performance computers built for applications that
require high CPU time and memory; numerical simulation becomes one of the more
effective approaches for such investigations and LES type of turbulence models can be
used more effectively.
Since there are objects that are touching each other in the present study, a special
approach was applied at the stage of building computational domain. This is supposed to
be a considerable improvement for CFD applications. Zero thickness was achieved
between the pebbles in which fission reaction takes place.
Since there is a strong pressure gradient as a result of high Reynolds Number on
the computational domain, which strongly affects the boundary layer behavior, heat
transfer in both laminar and turbulent flows varies noticeably. Therefore, noncircular
curved flows as in the pebble-bed situatio n, in detailed local sense, is interesting to be
investigated.
Since a compromise is needed between accuracy of results and time/cost of effort
in acquiring the results numerically, selection of turbulence model should be done
carefully. Resolving all the scales of a turbulent flow is too costly, while employing
highly empirical turbulence models to complex problems could give inaccurate
simulation results. The Large Eddy Simulation (LES) method would achieve the
requirements to obtain a reasonable result. In LES, the large scales in the flow are solved
and the small scales are modeled.
Eddy viscosity and Reynolds stress models were also be used to investigate the
applicability of these models for this kind of flow past bluff bodies at high Re numbers.
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Belluau, Michaël. "Traits fonctionnels, tolérances et distributions des espèces herbacées sur un gradient de disponibilité en eau : une approche prédictive par modèle d'équation structurale." Thèse, Université de Sherbrooke, 2017. http://hdl.handle.net/11143/11584.
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L’assemblage des espèces (leurs présences/absence) dans une communauté naturelle est la conséquence de plusieurs mécanismes de filtrage réalisés par l'environnement. Parmi ces filtres, le filtre abiotique sélectionne les espèces capables de tolérer les conditions environnementales locales. La variation de la disponibilité de l'eau dans le sol est l'un des principaux gradients environnementaux selon lesquels les espèces végétales sont différemment réparties. Considérant l’hypothèse que les traits fonctionnels et leurs relations sont hiérarchisées, les préférences d’habitat des espèces le long de gradients environnementaux devraient être déterminées par une combinaison de traits physiologiques et morpho-anatomiques hiérarchisés.
Au cours de ce doctorat, mon objectif général est d'identifier les traits fonctionnels morphologiques, anatomiques et physiologiques de tolérance à la sécheresse qui peuvent prédire la présence des espèces le long d'un gradient d’hydrologie des sols. Plus spécifiquement, nous cherchons à savoir : (i) Quels sont les traits physiologiques qui reflètent le mieux la tolérance à la sécheresse ? (ii) Quelles sont les relations entre les traits morpho-anatomiques et les traits physiologiques de tolérance ? (iii) Quels sont les traits morpho-anatomiques en conditions optimales permettant de prédire la tolérance des espèces herbacées à la sécheresse ? (iv) Quelles formes ont les relations qui existe entre les traits morpho-anatomiques de tolérance en condition optimale et la présence des espèces en cas de sécheresse ? (v) Peut-on prédire les présences des espèces en cas de sécheresse à partir de leurs traits morpho-anatomiques?
Nos résultats montrent (1) qu’il est possible de prédire la distribution des espèces sur un gradient d’hydrologie des sols à partir de cinq traits physiologiques de tolérance à la sécheresse. Ces cinq traits sont la photosynthèse nette maximale, la conductance stomatique maximale, le potentiel hydrique du sol au point de flétrissement, la conductance stomatique au point de flétrissement et l’efficacité d’utilisation de l’eau au point de flétrissement. Nous avons montré que (ii) les traits physiologiques de tolérance à la sécheresse sont prédits par les traits morpho-anatomiques en conditions optimales (surface spécifique foliaire, teneur en matière sèche des feuilles, teneur en azote foliaire, longueur spécifique racinaire et surface stomatique). (iii) Les traits morpho-anatomiques seuls ne sont pas de bons prédicteurs de l’hydrologie des espèces et (iv) que la séquence « traits morpho-anatomiques → traits physiologiques → hydrologie des espèces » donne les meilleures prédictions. Cependant, (v) le modèle ne donne pas de prédictions fiables si l’on utilise des traits morpho-anatomiques mesurés en conditions naturelles. Ces résultats confirment, au moins partiellement, l’hypothèse que la distribution des espèces sur un gradient hydrologiques peut être prédite à partir de leurs traits de tolérance à la sécheresse eux-mêmes prédits par leurs traits morpho-anatomiques.
En résumé, nous avons utilisé une approche fonctionnelle en construisant un modèle causal prédictif qui nous a permis de nous intéresser aux mécanismes de filtrage environnementaux et plus précisément au rôle de la niche hydrologique des espèces dans l’assemblage des communautés végétales.<br>Abstract : Species assembly (their presence/absence) in a natural community is the consequence of several filtering mechanisms made by the environment. Among these filters, the abiotic filter selects
species able to tolerate local environmental conditions. Variation in water availability in the soil is one of the main environmental gradients according to which plant species are differently distributed. Considering the hypothesis that functional traits and their relationships are hierarchical, habitat preferences of species along environmental gradients should be determined by a combination of hierarchical physiological and morpho-anatomical traits. During this PhD, my overall goal is to identify morphological, anatomical and physiological drought tolerance functional traits that can predict the presence of species along a soil hydrology gradient. More specifically : (i) What are the physiological traits that best reflect drought
tolerance? (ii) What are the relationships between morpho-anatomical traits and physiological traits of tolerance? (iii) What are the optimal morpho-anatomical traits for predicting tolerance of herbaceous species to drought? (iv) What forms of relationships exist between optimal morpho-anatomical traits of tolerance and the presence of species in drought condition? (v) Can the presence of species in drought condition be predicted from their morpho-anatomical features? Our results show (1) that it is possible to predict the distribution of species on a soil hydrology gradient from five physiological traits of drought tolerance. These five traits are maximum net photosynthesis, maximum stomatal conductance, water potential of the soil at the wilting point, stomatal conductance at the wilting point, and efficiency of water use at the wilting point. We have shown that (ii) the physiological traits of drought tolerance are predicted by optimal morpho-anatomical traits (leaf area, leaf dry matter content, leaf nitrogen content, root length
and stomatal surface). (iii) Morpho-anatomical features alone are not good predictors of species hydrology and (iv) the sequence “morpho-anatomical traits physiological traits species hydrology” gives the best predictions. However (v) the model does not provide reliable predictions using morpho-anatomical traits measured under natural conditions. These results confirm, at least partially, the hypothesis that the distribution of species on a hydrological gradient can be predicted from their drought tolerance traits themselves predicted by their morpho-anatomical features. In summary, we used a functional approach by constructing a predictive causal model that allowed us to focus on environmental filtering mechanisms and more specifically on the role of the species hydrological niche in assembling plant communities.
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Ion, Scotta Michela. "Distributions des espèces du genre Trichogramma le long d’un gradient altitudinal et adaptations locales aux basses températures chez l’espèce Trichogramma cacoeciae." Electronic Thesis or Diss., Université Côte d'Azur (ComUE), 2019. http://www.theses.fr/2019AZUR4035.
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Toutes les espèces sont confrontées à une hétérogénéité environnementale dans le temps et/ou dans l’espace et donc à des variations de la qualité de leur environnement local. Selon leurs biologies (capacité de dispersion, plasticité phénotypique, variabilité génétique locale, etc), les espèces répondent différemment mais cette hétérogénéité génère ou maintient in fine des variations inter- ou intra- spécifiques des traits d'histoire de vie. Dans ce contexte, ma thèse s’intéresse à (i) la distribution géographique et écologique des espèces du genre Trichogramma le long d’un gradient altitudinal dans une aire restreinte des Alpes Maritimes ; (ii) la mise en évidence chez l’une des espèces, d’éventuelles adaptations locales en relation avec les basses températures. Concernant ce deuxième volet, trois types d’expériences ont été menées à partir d’un ensemble de souches provenant des deux étages du gradient altitudinal (Méso- et Supra- méditerranéens) ainsi que des souches provenant d’une aire géographique plus septentrionale : (i) comparaison en laboratoire d’indices de tolérance thermique : Ctmin, Chill coma et Recover Activity ; (ii) étude des modalités d’overwintering sur le terrain ; (iii) étude des capacités de diapause. Mes résultats ont tout d’abord mis en évidence que, à l’échelle du transect altitudinal étudié et avec notre protocole d’échantillonnage, T. cacoeciae est l’espèce la plus largement distribuée et la plus abondante. De plus, les souches Supra - méditerranéennes semblent présenter par rapport aux souches Méso - méditerranéennes des différences génétiques, notamment dans leur propension à diapauser et dans leur vitesse de développement à basses températures. Cette différentiation génétique est encore plus marquée dans les souches plus septentrionales notamment pour leurs valeurs de Chill coma qui sont en moyenne plus basses. D’une façon générale, cette étude conclut sans ambiguïté à l’existence d’une variabilité intra-spécifique chez T. cacoeciae pour des traits liés à l’adaptation aux basses températures. Ces résultats, obtenus pour une seule espèce et à une échelle géographique restreinte, ouvrent donc la voie vers une étude plus systématique de ces traits et à la prise en compte/exploitation de leurs variabilités inter- et intra- spécifiques dans l’évaluation des trichogrammes comme auxiliaires de lutte biologique<br>All species are facing some environmental heterogeneity in time and / or space and thus with variations in the quality of their local environment. According to their biology (dispersal ability, phenotypic plasticity, local genetic variability, etc.), species respond differently but this heterogeneity usually generates or maintains inter-or intra-specific variations in life history traits. In this context, my thesis focuses on (i) the understanding of the geographical and ecological distributions of Trichogramma species along an altitudinal gradient in a narrow area of the department “Alpes-Maritimes”; (ii) –possible local adaptations to low temperatures in one of the encountered species. For this second part, three types of experiments were conducted from a set of strains from the two contrasted areas along the altitudinal gradient (Meso - and Supra - mediterranean) as well as strains from a more northern geographical area: (i) laboratory comparison of thermal tolerance indices: Ctmin, Chill coma and Recover Activity; (ii) study of diapause capabilities; (iii) study of overwintering modalities in the field. My results first showed that, at the scale of the altitudinal transect studied and with our sampling protocol, T. cacoeciae is the most widely distributed and abundant species. In addition, the Supra - mediterranean strains seem to have genetic differences with regard to the Meso - Mediterranean ones, particularly in their rate of development at low temperatures as well as their propensity to diapause. This genetic differentiation is even more marked in the more northern strains especially for their Chill coma values which are on average lower. Taken as a whole, this study unambiguously concludes that there is intra-specific variability in T. cacoeciae for traits related to adaptation to low temperatures. These results, obtained for a single species and on a small geographical scale, thus open the way towards a more systematic study of these traits and the taking into account/exploitation of their inter and intra-specific variabilities in the evaluation of trichograms as auxiliaries for biological control
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Sarker, Pratik. "Investigation of the Quenching Characteristics of Steel Components by Static and Dynamic Analyses." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1942.
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Machine components made of steel are subjected to heat treatment processes for improving mechanical properties in order to enhance product life and is usually done by quenching. During quenching, heat is transferred rapidly from the hot metal component to the quenchant and that rapid temperature drop induces phase transformation in the metal component. As a result, quenching generates some residual stresses and deformations in the material. Therefore, to estimate the temperature distribution, residual stress, and deformation computationally; three-dimensional finite element models are developed for two different steel components – a spur gear and a circular tube by a static and a dynamic quenching analyses, respectively. The time-varying nodal temperature distributions in both models are observed and the critical regions are identified. The variations of stress and deformation after quenching along different pathways for both models are studied. The convergence for both models is checked and validations of the models are done.
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Baddour, Nizar. "Etude instationnaire thermomecanique d'un lopin lors d'une operation de forgeage." Toulouse 3, 1988. http://www.theses.fr/1988TOU30176.
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Єфімова, Вероніка. "Алгоритмічні і програмні компоненти системи проектування процесу зміни температури сировини у випадку одночасного контактного впливу". Магістерська робота, Київський національний університет технологій та дизайну, 2021. https://er.knutd.edu.ua/handle/123456789/19283.
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Дипломну магістерську роботу присвячено дослідженню теоретичних задач активації процесу перенесення термореактивних смол і гідрофобних розчинів по товщині оброблюваних полотнищ тканини та обґрунтуванню практичних напрямів забезпечення більш рівномірного розподілу речовини по перетину тканини і окремих її волокон у випадку одночасного контактного впливу на основі розробки математичних та програмних компонентів САПР. Запропоновано аналітичні залежності між довжиною контактної зони, швидкістю руху тканини і температурою контактної поверхні та основні напрями практичного удосконалення механізму прогрівання полотнища тканини з використанням ефекту градієнта температур на основі розробки математичних та програмних компонентів САПР з урахуванням малої довжини контактної зони, деформації тканини в зоні транспортуючих циліндрів, ізольованості поверхні полотнища тканини в місці її контакту з навколишнім повітряним середовищем. Результати дипломної магістерської роботи можна використовувати для підвищення ефективності прогрівання полотнищ вологих віскозних та бавовняних тканин при її контактній сушці на поверхні сушильних пристроїв, що дозволить заощадити електроенергію та підвищити продуктивність процесу сушіння.<br>Дипломная магистерская работа посвящена исследованию теоретических задач активации процесса переноса термореактивных смол и гидрофобных растворов по толщине обрабатываемых полотнищ ткани и обоснованию практических направлений обеспечения более равномерного распределения вещества по сечению ткани и отдельных ее волокон в случае одновременного контактного воздействия на основе разработки математических и программных компонентов САПР. Предложены аналитические зависимости между длиной контактной зоны, скоростью движения ткани и температурой контактной поверхности. Рекомендованы основные направления практического усовершенствования механизма прогрева полотнища ткани. Для чего использовался эффект градиента температур на основе разработки математических и программных компонентов САПР с учетом малой длины контактной зоны, деформации ткани в зоне транспортирующих цилиндров, изолированности поверхности полотнища ткани в месте ее контакта с окружающей воздушной средой. Результаты дипломной магистерской работы можно использовать для повышения эффективности прогрева полотнищ вискозных и хлопчатобумажных тканей при контактной сушке на поверхности сушильных устройств, что позволит сэкономить электроэнергию и повысить производительность процесса сушки.<br>The master's thesis is devoted to the study of theoretical problems of activation of the transfer process of thermosetting resins and hydrophobic solutions through the thickness of the processed fabric panels and the substantiation of practical directions for ensuring a more uniform distribution of matter over the cross section of the fabric and its individual fibers in the case of simultaneous contact action based on the development of mathematical and software components of CAD. Analytical relationships between the length of the contact zone, the speed of tissue movement and the temperature of the contact surface are proposed. The main directions of practical improvement of the mechanism for warming up the cloth panel are recommended. For this, the effect of the temperature gradient was used on the basis of the development of mathematical and software components of CAD, taking into account the small length of the contact zone, deformation of the tissue in the zone of the transporting cylinders, and the isolation of the surface of the cloth in the place of its contact with the surrounding air environment. The results of the master's thesis can be used to increase the efficiency of heating viscose and cotton fabrics during contact drying on the surface of drying devices, which will save energy and increase the productivity of the drying process.
Books on the topic "Temperature gradient and Stress distribution"
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M, Jenkins Rhonald, and United States. National Aeronautics and Space Administration., eds. Analysis supporting MSFC cryostat testing unit: Final report. National Aeronautics and Space Administration, 1997.
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Patrick, Dunn, and United States. National Aeronautics and Space Administration., eds. An evaluation of a coupled microstructural approach for the analysis of functionally graded composites via the finite-element method. National Aeronautics and Space Administration, 1995.
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1935-, Aboudi Jacob, Arnold S. M, and NASA Glenn Research Center, eds. The effect of interface roughness and oxide film thickness on the inelastic response of thermal barrier coatings to thermal cycling. National Aeronautics and Space Administration, Glenn Research Center, 1999.
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United States. National Aeronautics and Space Administration., ed. Creep and stress relaxaton modeling of polycrystalline ceramic fibers. National Aeronautics and Space Administration, 1994.
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Abdul-Aziz, Ali. Design evaluation using finite element analysis of cooled silicon nitride plates for a turbine blade application. National Aeronautics and Space Administration, Glenn Research Center, 2001.
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Abdul-Aziz, Ali. Design evaluation using finite element analysis of cooled silicon nitride plates for a turbine blade application. National Aeronautics and Space Administration, Glenn Research Center, 2001.
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Sherwood, Dennis, and Paul Dalby. Temperature and heat. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198782957.003.0003.
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Concepts of temperature, temperature scales and temperature measurement. The ideal gas law, Dalton’s law of partial pressure. Assumptions underlying the ideal gas, and distinction between ideal and real gases. Introduction to equations-of-state such as the van der Waals, Dieterici, Berthelot and virial equations, which describe real gases. Concept of heat, and distinction between heat and temperature. Experiments of Rumford and Joule, and the principle of the conservation of energy. Units of measurement for heat. Heat as a path function. Flow of heat down a temperature gradient as an irreversible and unidirectional process. ‘Zeroth’ Law of Thermodynamics. Definitions of isolated, closed and open systems, and of isothermal, adiabatic, isobaric and isothermal changes in state. Connection between work and heat, as illustrated by the steam engine. The molecular interpretation of heat, energy and temperature. The Boltzmann distribution. Meaning of negative temperatures.
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The effect of interface roughness and oxide film thickness on the inelastic response of thermal barrier coatings to thermal cycling. National Aeronautics and Space Administration, Glenn Research Center, 1999.
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Kiss, Thomas, and Paolo Pelosi. Lung recruitment techniques in the ICU. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0120.
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Lung recruitment manoeuvres (RMs) have been suggested as a means of homogenizing the lung structure and distribution of the mechanical stress across the lungs. Such effects can be achieved provided enough pressure is applied for enough time at the airways, and maintained if adequate levels of positive end-expiratory pressure (PEEP) are used. When RMs effectively open atelectatic tissue, shear stress, and cyclic collapse/reopening are importantly reduced. The lung response to RMs is mainly determined by cause and severity of lung injury, and the position of the lungs with respect to the gravity gradient. RMs can be performed in several different ways, the most relevant RMs in terms of clinical applicability are sustained inflation manoeuvres, high pressure controlled ventilation, incremental PEEP, and intermittent sighs.
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Zaitchik, Benjamin F. Climate and Health across Africa. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228620.013.555.
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Humans have understood the importance of climate to human health since ancient times. In some cases, the connections appear to be obvious: a flood can cause drownings, a drought can lead to crop failure and hunger, and temperature extremes pose a risk of exposure. In other cases, the connections are veiled by complex or unobserved processes, such that the influence of climate on a disease epidemic or a conflict can be difficult to diagnose. In reality, however, all climate impacts on health are mediated by some combination of natural and human dynamics that cause individuals or populations to be vulnerable to the effects of a variable or changing climate.Understanding and managing negative health impacts of climate is a global challenge. The challenge is greater in regions with high poverty and weak institutions, however, and Africa is a continent where the health burden of climate is particularly acute. Observed climate variability in the modern era has been associated with widespread food insecurity, significant epidemics of infectious disease, and loss of life and livelihoods to climate extremes. Anthropogenic climate change is a further stress that has the potential to increase malnutrition, alter the distribution of diseases, and bring more frequent hydrological and temperature extremes to many regions across the continent.Skillful early warning systems and informed climate change adaptation strategies have the potential to enhance resilience to short-term climate variability and to buffer against negative impacts of climate change. But effective warnings and projections require both scientific and institutional capacity to address complex processes that are mediated by physical, ecological, and societal systems. Here the state of understanding climate impacts on health in Africa is summarized through a selective review that focuses on food security, infectious disease, and extreme events. The potential to apply scientific understanding to early warning and climate change projection is also considered.
Book chapters on the topic "Temperature gradient and Stress distribution"
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Wang, X. B. "Nonuniform Temperature Distribution in Adiabatic Shear Band Using Measured Shear Stress-Shear Strain Curve in Torsion of Thin-Walled Tube Aluminium Alloy Specimen and Gradient-Dependent Plasticity." In Materials Science Forum. Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/0-87849-408-1.865.
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Vermaat, J. E., and M. J. M. Hootsmans. "Periphyton dynamics in a temperature-light gradient." In Lake Veluwe, a Macrophyte-dominated System under Eutrophication Stress. Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-2032-6_12.
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Yoo, Han-Ill, and B. J. Wuensch. "Concentration Distribution for Diffusion in A Temperature Gradient." In Transport in Nonstoichiometric Compounds. Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2519-2_14.
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Vermaat, J. E., and M. J. M. Hootsmans. "Growth of Potamogeton pectinatus L. in a temperature-light gradient." In Lake Veluwe, a Macrophyte-dominated System under Eutrophication Stress. Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-2032-6_5.
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Wang, Yawei, Qi Li, Qingzhao Liu, and Xiaoliang Zhang. "Simulation of Stress and Temperature Distribution of Drive Coil." In Lecture Notes in Electrical Engineering. Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-1428-5_72.
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Jiang, Yu, and Peiheng Long. "Parameter Sensitivity Analysis of Long Span PC Continuous Beam Bridge with Corrugated Steel Webs." In Lecture Notes in Civil Engineering. Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1260-3_26.
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AbstractIn order to explore the regularity of alignment and stress variation of long-span corrugated steel web (CSW) continuous beam bridge during cantilever casting construction was taken as the engineering background. Based on numerical simulation, the sensitivity of parameters of alignment and stress of the main beam is carried out on cast-in-place section weight, modulus of elasticity and temperature gradient. The results show that the obvious influence of cast-in-situ section weight and temperature gradient on the alignment and stress is the key control parameters, while modulus of elasticity is the secondary control parameters. Therefore, it is necessary to monitor concrete dense and environmental temperature change in real time during construction, closure at a suitable temperature. Correct construction errors in time, ensure structural safety and smooth alignment.
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Hemrick, James G., Edgar Lara-Curzio, and James F. King. "Long-Term Temperature Gradient Stress Relaxation Testing and Modeling of Ceramic Insulation Materials." In Mechanical Properties and Performance of Engineering Ceramics and Composites IV. John Wiley & Sons, Inc., 2009. http://dx.doi.org/10.1002/9780470584262.ch7.
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Elleuch, Sameh, Hanen Jrad, Mondher Wali, and Fakhreddine Dammak. "Influence of Material Gradient Index on Stress Distribution of Functionally Graded Dental Implants." In Lecture Notes in Mechanical Engineering. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-52071-7_2.
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Li, Huaming, Mingchen Xia, Shize Zheng, and Jingxian Ding. "Thermal Impact Analysis of Brake Discs Under Extreme Working Conditions of Trackless Trains Based on Virtual Testing." In Lecture Notes in Mechanical Engineering. Springer Nature Singapore, 2025. https://doi.org/10.1007/978-981-97-7887-4_115.
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Abstract Trackless trains adopt public right-of-way. The braking distance requirements are strict, and large deceleration is required to stop the train. Brake disc is an important part of the trackless train, its service performance directly affects the braking safety of the train, and the temperature and stress are the key performance parameters. In order to investigate the influence law of variable working conditions on the temperature and stress of the brake disc, for the problem that it is difficult to simulate the extreme working conditions based on the real measurement method, the brake disc of a 3-vehicle and 6-axle trackless train is taken as the research object. According to the structural dimensions and material parameters, a thermo-mechanical coupling simulation model of the brake disc is established based on the theories of transient thermodynamics and heat transfer. Based on the standard comparison analysis, the deceleration index of the trackless train to meet the requirements of braking distance is designed, and the virtual test of the temperature and stress field of the brake disc is carried out under the conditions of different loads, deceleration, and ramp gradient. The results show that it is feasible to simulate the extreme working conditions based on the virtual test, and the maximum temperature and stress of the brake disc increase with the increase of load, deceleration and ramp gradient. Under the extreme working conditions, the maximum temperature of the brake disc is about 680.4 ℃, and the maximum stress is about 1240 MPa. The research results provide a reference for the safe operation and maintenance of the trackless train.
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Kovacs, Adam, and Horst Lippmann. "The Effect of a Temperature Cycle on the Stress Distribution in a Shrink Fit." In Anisotropy and Localization of Plastic Deformation. Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3644-0_146.
Full textConference papers on the topic "Temperature gradient and Stress distribution"
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Miura, Yasufumi, Kenji Kako, Yuichi Miyahara, and Masaru Sato. "Effects of Plastic Strain and Stress Distribution on SCC Initiation in High Temperature Water." In CORROSION 2013. NACE International, 2013. https://doi.org/10.5006/c2013-02442.
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Abstract Stress corrosion cracking (SCC) has been occurred in boiling water reactor (BWR) components, such as reactor core shrouds and primary loop recirculation (PLR) pipes made of L-grade austenitic stainless steels, which are not thermally sensitized. SCC of reactor core shrouds and PLR pipes is generally initiated on work hardened surfaces. Therefore it is important to clarify the effect of work hardened surface layer on SCC initiation behavior. In this study, SCC initiation tests, x-ray stress measurements, hardness tests, and optical microscope observations were carried out in order to evaluate effects of plastic strain and stress distribution on SCC initiation. Specimens with cyclic plastic strain distribution introduced by face milling showed that SCC was preferentially initiated in areas with a large plastic strain gradient. In addition, stress measurement using x-ray diffraction clarified that stress distribution on the specimen was negatively correlated with hardness corresponding to plastic strain distribution. As a result of these studies, it was suggested that SCC tended to be initiated in areas with a stress and hardness gradient.
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Zhang, Wei, Yiyu Wang, Yanli Wang, et al. "Modeling-Based Design and Optimization of a Gradient Composite Transition Joint." In AM-EPRI 2024. ASM International, 2024. http://dx.doi.org/10.31399/asm.cp.am-epri-2024p1313.
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Abstract An innovative additively manufactured gradient composite transition joint (AM-GCTJ) has been designed to join dissimilar metals, to address the pressing issue of premature failure observed in conventional dissimilar metal welds (DMWs) when subjected to increased cyclic operating conditions of fossil fuel power plants. The transition design, guided by computational modeling, developed a gradient composite material distribution, facilitating a smooth transition in material volume fraction and physical properties between different alloys. This innovative design seeks to alleviate structural challenges arising from distinct material properties, including high thermal stress and potential cracking issues resulting from the thermal expansion mismatch typically observed in conventional DMWs. In this study, we investigated the creep properties of transition joints comprising Grade 91 steel and 304 stainless steel through a combination of simulations and creep testing experiments. The implementation of a gradient composite design in the plate transition joint resulted in a significant enhancement of creep resistance when compared to the baseline conventional DMW. For instance, the creep rupture life of the transition joint was improved by &gt; 400% in a wide range of temperature and stress testing conditions. Meanwhile, the failure location shifted to the base material of Grade 91 steel. Such enhancement can be primarily attributed to the strong mechanical constraint facilitated by the gradient composite design, which effectively reduced the stresses on the less creep-resistant alloy in the transition zone. Beyond examining plate joints, it is crucial to assess the deformation response of tubular transition joints under pressure loading and transient temperature conditions to substantiate and demonstrate the effectiveness of the design. The simulation results affirm that the tubular transition joint demonstrates superior resistance compared to its counterpart DMW when subjected to multiaxial stresses in tubular structures. In addition, optimization of the transition joint’s geometry dimensions has been conducted to diminish the accumulated deformation and enhance the service life. Lastly, the scalability and potential of the innovative transition joints for large-diameter pipe applications are addressed.
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Zhu, Jianwei, Shiyi Bao, Yuebing Li, and Zengliang Gao. "Creep Analysis of Hemisphere Shell Structure Under High Temperature Gradient." In ASME 2014 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/pvp2014-29078.
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The In-Vessel Retention (IVR) of molten core debris has been part of the severe accident management strategy for advanced pressurized water reactor (PWR) plant. Generally, the pressure is supposed to successfully be released, and the externally cooled lower head wall mainly experiences the temperature difference which may be more than 1000°C. However, the Fukushima accident shows that a certain pressure (up to 8.0MPa) still exists inside the reactor pressure vessel (RPV). Therefore, in order to make the IVR succeed, it is necessary to investigate the structural integrity of the RPV under the combined internal pressure and the thermal load on the lower head. Therefore, it is supposed that the lower head of RPV is a Hemisphere Shell Structure (HSS) with 2150mm external radius and 25mm wall thickness. Similarly, the outer wall temperature is supposed to be 127°C, the wall temperature difference 1200°C, and the material properties (i.e., thermal conductivity, specific heat capacity, yield strength, and so on) are dependent on the temperature. In this paper, the main subjects discussed are as below. First, the heat transfer analysis is carried out to obtain the temperature distribution of the HSS wall. Due to the high temperature gradient, there may present different failure modes along the HSS wall thickness, i.e., plastic failure and creep failure. Then, the stress and strain distributions along the wall thickness are analyzed by ANSYS finite element method where the Norton-Bailey type creep law is adopted. The result shows that the stress in the lower temperature part (LTP) whose temperature is lower than 405°C is lower than the yield stress of the material with the corresponding temperature. That is to say, the LTP still can bear a certain internal pressure. At last, to consider the combined impact of internal pressure and temperature difference on the HSS, the finite element analysis is carried out by adopting the isochronous stress-strain curves of the Chinese RPV material. The relationship between the stress in the LTP at 100 hours and the internal pressure is discussed, and the limit internal pressure is determined. It is concluded that HSS still can maintain its integrity under IVR, even if there exists a certain internal pressure.
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Andritschky, M., V. Teixeira, and D. Stöver. "Thermal Residual Stresses in Functionally Gradient Coatings." In ITSC 1997, edited by C. C. Berndt. ASM International, 1997. http://dx.doi.org/10.31399/asm.cp.itsc1997p0847.
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Abstract The present contribution concerns with a numerical modelling of the residual stress distribution within a multilayered coating system which consists of a functionally gradient material (FGM). The structure of the graded system is made of a ceramic layer and a metallic layer, where between them there is an interlayer which is a graded composite made of the metal and ceramic. The composition changes gradually from 0% ceramic to 100% ceramic. This graded interlayer was modelled as a serie of perfectly bonded finite thin layers, each having slightly different material properties. We analyse the FGM design in respect to thermal stress optimization (e.g. reduction the interfacial stresses). The case of a bilayer, thick ceramic coating on a metallic substrate and a graded thermal barrier coating (TBC) is considered. The effects on thermal residual stress gradients of the compositional profiles and graded interlayer thickness were studied. This FGM stress model enable us to calculate the thermal strain and stress distributions, which gives a contribute to a better understanding of the failure of a graded coating system and is, therefore, a potential tool for FGM stress optimization to improve the thermo-mechanical stability of multilayer graded structures such as high temperature ceramic coatings for use in thermal barrier applications.
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Liao, Hanlin, Hao Deng, and Christian Coddet. "Conjugated Gradient Method for Estimating Inversely the Flux Distribution of Cooling Jets." In ITSC2003, edited by Basil R. Marple and Christian Moreau. ASM International, 2003. http://dx.doi.org/10.31399/asm.cp.itsc2003p0981.
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Abstract It is necessary to cool specimens during spraying in the case APS or HVOF, because process-induced heat rises the specimen temperature and leads to oxidation and spalling of coatings. A reasonable cooling just after spraying improves some properties such as microhardness, adhesion and cohesion of the coating/substrate system. In the modelling of specimen temperature and residual stress, it is necessary to know the flux distribution of the cooling jet like compressed air, CO2 liquid jet etc. Therefore, the evaluation of the flux becomes important. In order to measure and analyse the distribution of cooling flux imposed on the substrate, the theory of the inverse problem of heat conduction was applied and an experimental apparatus was designed to mesure the transient temperature. Because of its insensibility to the effect of measuring error, the conjugate gradient method, an effective method of inverse problems was chosen among several mathematical optimisation methods. The flux distributions of cooling jet can be estimated by using the measured data and a program written according to the conjugate gradient method.
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Reinhardt, W., and A. Asadkarami. "The Shakedown Boundary for Parabolic Stress Distribution in NB-3222.5." In ASME 2013 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/pvp2013-98090.
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The rules for the prevention of thermal stress ratchet in NB-3222.5 address the interaction of general primary membrane stress with two types of cyclic thermal loading. The first is a linear through-wall temperature gradient, for which the shakedown boundary is given by the well-known Bree diagram. The Code provides a second shakedown boundary for the interaction of general primary membrane stress with a “parabolic” temperature distribution. The corresponding ratchet boundary is fully defined in the elastic range, but only three points are given in the elastic-plastic regime. The range of validity of this ratchet boundary in terms of the thermal stress distribution (does “parabolic” mean second-order in the thickness coordinate or any polynomial of degree greater than one? If it is second-order, are there any further restrictions?) is not well defined in NB-3222.5. Using a direct lower bound method of shakedown analysis, the non-cyclic method, an exact analytical solution is derived for the shakedown boundary corresponding to the interaction of general primary membrane stress with a cyclic “parabolic” temperature distribution. By comparison to what is given in NB-3222.5, the thermal condition for which the Code equation is valid is defined and its range of validity is established. To study the transition behavior to the steady state and to confirm the analytical solution, numerical results using an FE model are also obtained.
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Soda, Kohei, Takato Mizutani, and Naoto Kasahara. "Thermal Stress Response to Boundary Oscillation Between Hot and Cold Fluid Temperature." In ASME 2014 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/pvp2014-28393.
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In nuclear power plants, high cycle thermal fatigue induced by temperature fluctuation of the coolant is one of frequent failure modes. To ensure the safety of nuclear power plant systems, it is important to prevent thermal fatigue failure. Typical causes of high cycle thermal fatigue are thermal striping at Tee-junction and thermal stratification oscillation. In order to evaluate thermal stress caused by thermal striping, a frequency response function has been developed. This function was derived from a heat transfer and thermal elastic theories, and can adequately evaluate thermal stress induced by temperature gradient into wall-thickness direction. However, this theoretical method cannot adequately evaluate thermal stress by thermal stratification oscillation, because this phenomenon has the fluid temperature distribution gradient along axial direction. To investigate the mechanism of thermal stress generated by oscillation of thermal stratification, two types of models were studied. In the first type, fluid temperature oscillates with sinusoidal history at the same location, and in the second one, the boundary layer of hot and cold fluid temperature moves with sinusoidal velocity. Through clarification of the stress generation mechanism, the frequency response function was improved to evaluate stress by the thermal stratification oscillation. Applicability of this function was verified through agreement with finite element simulations.
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Lan, Weiping, Dachao Lin, Zulong Hao, and Fenglei Niu. "Stress Analysis of Three-Layer SiC Cladding for PWRs." In 2017 25th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/icone25-66814.
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Silicon carbide (SiC) and SiC matrix composites (SiCf/SiC) are being investigated as potential fuel cladding materials for advanced PWRs in order to improve the safety of nuclear power plants. The conceptual design of multi-layered SiC cladding (consisting of a monolithic SiC layer, SiCf/SiC composite layer and a monolithic SiC coating layer) has been investigated to meet the fuel requirements of both the strength and impermeability. A stress distribution model of the triple-layered SiC is developed on the basis of the theory of thermo-elasticity mechanics, taking radial temperature gradient and swelling effects into account as well. The heat transferring behavior of the cladding is investigated by analyzing the temperature distribution under steady conditions. Finite Element Analysis (FEA) code ANSYS is used to obtain the stress and temperature nephogram of multi-layered SiC fuel cladding under simulated steady conditions. Compared with the results of ANSYS, the stress distribution model and temperature distribution is validated.
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Laskin, Igor, Boris Volfson, and Pavel Redikultsev. "The Study of the Effect of the Hot Box on the Stress-Strain State of the High Temperature Petrochemical Vessels." In ASME 2018 Symposium on Elevated Temperature Application of Materials for Fossil, Nuclear, and Petrochemical Industries. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/etam2018-6733.
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The majority of studies of the heat transfer inside the hot box treats the heat transfer as a steady-state process. This paper demonstrates that this approach cannot be applied to the most dangerous cases of the cyclic thermal stress. The significant thermal gradients may occur in the skirt to shell junction of a high-temperature vessel and set up critical thermal stresses. It is a common practice to use a hot box to equalize temperatures of a shell and a skirt support. Reduction of thermal gradient results from a radiative heat transfer inside this hot box. Where a heating/cooling rate is high enough, as in coke drums, for example, the accounting of transient alters radically the distribution of a thermal stress state, and allows us to reconsider the mechanics of the fracture growth in the skirt to shell weld. This paper proves that during the cooling of coke drums some parts of the skirt support have higher temperatures than the shell, which causes tensile circumferential stresses in the weld. The intensity of the radiative heat transfer falls rapidly, when cooling a shell down to 247 °C, which leads to the increase of thermal gradients in the weld zone. This paper proposes a solution to the thermal problem in 2D, and strain-state analysis — in 3D, due to the presence of skirt slots equally spaced around skirt circumference, which increases the circumferential flexibility. The two-dimensional thermal field has been interpolated to a three-dimensional hexagonal grid for solving the thermo-strength transient problem.
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Khalilollahi, Amir, and Russell L. Warley. "Thermal Stress Reduction and Optimization for Orthotropic Composite Boards." In ASME 2005 Summer Heat Transfer Conference collocated with the ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems. ASMEDC, 2005. http://dx.doi.org/10.1115/ht2005-72570.
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Composite printed electronic boards are susceptible of structural failure or irreversible damage under thermally raised stresses. A thermal/structural finite element model is integrated in this study to enable the predictions of the temperature and stress distribution of vertically clamped parallel circuit boards that include series of symmetrically mounted heated electronic modules (chips). The board is modeled as a thin plate containing four heated flush rectangular areas that represent the electronic modules. The finite element model should be to able to accept the convection heat transfer on the board surface, heat generation in the modules, and directional conduction inside the board. A detailed 3-D CFD model is incorporated to predict the conjugate heat transfer coefficients that strongly affect the temperature distribution in the board and modules. Structural analyses are performed by a FE model that uses the heat transfer coefficients mentioned above, and structural elements capable of handling orthotropic material properties. The stress fields are obtained and compared for the models possessing different fiber orientations and fiber volume fractions. Appreciable differences in stress and thermal gradient fields were observed. The values of fiber volume fraction and fiber orientation at which to conduct analyses was guided by experimental design (DOE) ideas leading to a metamodel of the stress intensity and temperature gradient in the board which was used to represent the complied results of this study.
Reports on the topic "Temperature gradient and Stress distribution"
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Shores, D. A., J. H. Stout, and W. W. Gerberich. Fundamental studies of stress distribution and stress relaxation in oxide scales on high temperature alloys. Final report, November 1, 1987--October 31, 1995. Office of Scientific and Technical Information (OSTI), 1997. http://dx.doi.org/10.2172/532600.
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Liu, X., Z. Chen, and S. E. Grasby. Using shallow temperature measurements to evaluate thermal flux anomalies in the southern Mount Meager volcanic area, British Columbia, Canada. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330009.
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Geothermal is a clean and renewable energy resource. However, locating where elevated thermal gradient anomalies exist is a significant challenge when trying to assess potential resource volumes during early exploration of a prospective geothermal area. In this study, we deployed 22 temperature probes in the shallow subsurface along the south flank of the Mount Meager volcanic complex, to measure the transient temperature variation from September 2020 to August 2021. In our data analysis, a novel approach was developed to estimate the near-surface thermal distribution, and a workflow and code with python language have been completed for the thermal data pre-processing and analysis. The long-term temperature variation at different depths can be estimated by modelling, so that the relative difference of deducing deeper geothermal gradient anomalies can be assessed. Our proposed inversion and simulation methods were applied to calculating the temperature variation at 2.0 meters depth. The results identified a preferred high thermal flux anomalous zone in the south Mount Meager area. By combining with previous studies, the direct analysis and estimation of anomalous thermal fields based on the collected temperature data can provide a significant reference for interpretation of the regional thermal gradient variation.
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Guy, Charles, Gozal Ben-Hayyim, Gloria Moore, Doron Holland, and Yuval Eshdat. Common Mechanisms of Response to the Stresses of High Salinity and Low Temperature and Genetic Mapping of Stress Tolerance Loci in Citrus. United States Department of Agriculture, 1995. http://dx.doi.org/10.32747/1995.7613013.bard.
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The objectives that were outlined in our original proposal have largely been achieved or will be so by the end of the project in February 1995 with one exception; that of mapping cold tolerance loci based on the segregation of tolerance in the BC1 progeny population. Briefly, our goals were to 1) construct a densely populated linkage map of the citrus genome: 2) map loci important in cold and/or salt stress tolerance; and 3) characterize the expression of genes responsive to cold land salt stress. As can be seen by the preceding listing of accomplishments, our original objectives A and B have been realized, objective C has been partially tested, objective D has been completed, and work on objectives E and F will be completed by the end of 1995. Although we have yet to map any loci that contribute to an ability of citrus to maintain growth when irrigated with saline water, our very encouraging results from the 1993 experiment provides us with considerable hope that 1994's much more comprehensive and better controlled experiment will yield the desired results once the data has been fully analyzed. Part of our optimism derives from the findings that loci for growth are closely linked with loci associated with foliar Cl- and Na+ accumulation patterns under non-salinization conditions. In the 1994 experiment, if ion exclusion or sequestration traits are segregating in the population, the experimental design will permit their resolution. Our fortunes with respect to cold tolerance is another situation. In three attempts to quantitatively characterize cold tolerance as an LT50, the results have been too variable and the incremental differences between sensitive and tolerant too small to use for mapping. To adequately determine the LT50 requires many plants, many more than we have been able to generate in the time and space available by making cuttings from small greenhouse-grown stock plants. As it has turned out, with citrus, to prepare enough plants needed to be successful in this objective would have required extensive facilities for both growing and testing hardiness which simply were not available at University of Florida. The large populations necessary to overcome the variability we encountered was unanticipated and unforeseeable at the project's outset. In spite of the setbacks, this project, when it is finally complete will be exceedingly successful. Listing of Accomplishments During the funded interval we have accomplished the following objectives: Developed a reasonably high density linkage map for citrus - mapped the loci for two cold responsive genes that were cloned from Poncirus - mapped the loci for csa, the salt responsive gene for glutathione peroxidase, and ccr a circadian rhythm gene from citrus - identified loci that confer parental derived specific DNA methylation patterns in the Citrus X Poncirus cross - mapped 5 loci that determine shoot vigor - mapped 2 loci that influence leaf Na+ accumulation patterns under non-saline conditions in the BC1 population - mapped 3 loci that influence leaf Na+ accumulation paterns during salt sress - mapped 2 loci that control leaf Cl- accumulation patterns under non-saline conditions - mapped a locus that controls leaf Cl- accumulation patterns during salt stress Screened the BC1 population for growth reduction during salinization (controls and salinized), and cold tolerance - determined population variation for shoot/root ratio of Na+ and Cl- - determined levels for 12 inorganic nutrient elements in an effort to examine the influence of salinization on ion content with emphasis on foliar responses - collected data on ion distribution to reveal patterns of exclusion/sequestration/ accumulation - analyzed relationships between ion content and growth Characterization of gene expression in response to salt or cold stress - cloned the gene for the salt responsive protein csa, identified it as glutathione peroxidase, determined the potential target substrate from enzymatic studies - cloned two other genes responsive to salt stress, one for the citrus homologue of a Lea5, and the other for an "oleosin" like gene - cold regulated (cor) genes belonging to five hybridization classes were isolated from Poncirus, two belonged to the group 2 Lea superfamily of stress proteins, the others show no significant homology to other known sequences - the expression of csa during cold acclimation was examined, and the expression of some of the cor genes were examined in response to salt stress - the influence of salinization on cold tolerance has been examined with seedling populations - conducted protein blot studies for expression of cold stress proteins during salt stress and vice versa
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Blum, Abraham, Henry T. Nguyen, and N. Y. Klueva. The Genetics of Heat Shock Proteins in Wheat in Relation to Heat Tolerance and Yield. United States Department of Agriculture, 1993. http://dx.doi.org/10.32747/1993.7568105.bard.
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Fifty six diverse spring wheat cultivars were evaluated for genetic variation and heritability for thermotolerance in terms of cell-membrane stability (CMS) and triphenyl tetrazolium chloride (TTC) reduction. The most divergent cultivars for thermotolerance (Danbata-tolerant and Nacozari-susceptible) were crossed to develop an F8 random onbred line (RIL) population. This population was evaluated for co-segragation in CMS, yield under heat stress and HSP accumulation. Further studies of thermotolerance in relations to HSP and the expression of heterosis for growth under heat stress were performed with F1 hybrids of wheat and their parental cultivars. CMS in 95 RILs ranged from 76.5% to 22.4% with 71.5% and 31.3% in Danbata and Nacozari, respectively. The population segregated with a normal distribution across the full range of the parental values. Yield and biomass under non-stress conditions during the normal winter season at Bet Dagan dit not differ between the two parental cultivar, but the range of segregation for these traits in 138 RILs was very high and distinctly transgressive with a CV of 35.3% and 42.4% among lines for biomass and yield, respectively. Mean biomass and yield of the population was reduced about twofold when grown under the hot summer conditions (irrigated) at Bet Dagan. Segregation for biomass and yield was decreased relative to the normal winter conditions with CV of 20.2% and 23.3% among lines for biomass and yield, respectively. However, contrary to non-stress conditions, the parental cultivars differed about twofold in biomass and yield under heat stress and the population segregated with normal distribution across the full range of this difference. CMS was highly and positively correlated across 79 RILs with biomass (r=0.62**) and yield (r=0.58**) under heat stress. No such correlation was obtained under the normal winter conditions. All RILs expressed a set of HSPs under heat shock (37oC for 2 h). No variation was detected among RILs in high molecular weight HSP isoforms and they were similar to the patterns of the parental cultivars. There was a surprisingly low variability in low molecular weight HSP isoforms. Only one low molecular weight and Nacozari-specific HSP isoform (belonging to HSP 16.9 family) appeared to segregate among all RILs, but it was not quantitatively correlated with any parameter of plant production under heat stress or with CMS in this population. It is concluded that this Danbata/Nacozari F8 RIL population co-segregated well for thermotolerance and yield under heat stress and that CMS could predict the relative productivity of lines under chronic heat stress. Regretfully this population did not express meaningful variability for HSP accumulation under heat shock and therefore no role could be seen for HSP in the heat tolerance of this population. In the study of seven F1 hybrids and their parent cultivars it was found that heterosis (superiority of the F1 over the best parent) for CMs was generally lower than that for growth under heat stress. Hybrids varied in the rate of heterosis for growth at normal (15o/25o) and at high (25o/35o) temperatures. In certain hybrids heterosis for growth significantly increased at high temperature as compared with normal temperature, suggesting temperature-dependent heterosis. Generally, under normal temperature, only limited qualitative variation was detected in the patterns of protein synthesis in four wheat hybrids and their parents. However, a singular protein (C47/5.88) was specifically expressed only in the most heterotic hybrid at normal temperature but not in its parent cultivars. Parental cultivars were significantly different in the sets of synthesized HSP at 37o. No qualitative changes in the patterns of protein expression under heat stress were correlated with heterosis. However, a quantitative increase in certain low molecular weight HSP (mainly H14/5.5 and H14.5.6, belonging to the HSP16.9 family) was positively associated with greater heterosis for growth at high temperature. None of these proteins were correlated with CMS across hybrids. These results support the concept of temperature-dependent heterosis for growth and a possible role for HSP 16.9 family in this respect. Finally, when all experiments are viewed together, it is encouraging to find that genetic variation in wheat yield under chronic heat stress is associated with and well predicted by CMS as an assay of thermotolerance. On the other hand the results for HSP are elusive. While very low genetic variation was expressed for HSP in the RIL population, a unique low molecular weight HSP (of the HSP 16.9 family) could be associated with temperature dependant heterosis for growth.
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Klinger, Richard. Bachelor-MARSYS education cruise in the Baltic Sea Cruise No. AL577, 28.07. – 08.08.2022, Kiel (Germany) – Kiel (Germany) BALTEACH - 1. Institute for Marine Ecosystem and Fishery Science, Kiel, Germany, 2022. http://dx.doi.org/10.3289/cr_al577.
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During this teaching cruise, bachelor students of the Institute of Marine Ecosystem and Fishery Science (IMF) were supposed to get the opportunity to learn about the most commonly used scientific methods, gears and working procedures on board of a research vessel for fisheries science as well as biological oceanography. In order to achieve a great number of students participating a teaching cruise, this one has been split in half. Thus a change of 7 students has been realizable in Rønne, on the Danish island Bornholm. The scientific objective of the cruise was the investigation of distribution patterns of certain spawning fish species, such as cod, whiting, sprat, plaice, flounder and dab in the Kiel, Arkona and with special focus within the Bornholm Basin. In addition to fisheries, a comprehensive grid of plankton net stations was sampled in order to gain insights into the spatial distribution of fish eggs, planktivorous prey (larval to adult life stages) cod larvae and plankton distribution (most important for sprat) within the Bornholm Basin. Of special interest were picoplankton communities´ short term responses (on board) to temperature along the respective gradient in the Baltic Sea with an additional sampling scheme to later isolate Ostreococcus sp. and its associated viruses for future laboratory studies at the Institute for Marine Ecosystem and Fishery Science. (Alkor-Berichte ; AL577)
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Maupin, Julie, and Dr Michael Mamoun. DTPH56-06-T-0004 Plastic Pipe Failure, Risk, and Threat Analysis. Pipeline Research Council International, Inc. (PRCI), 2006. http://dx.doi.org/10.55274/r0012119.
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Reports, publications, papers, and databases were reviewed to better define risks and threats to plastic gas distribution piping. Failure modes were described for plastic PE piping with the most significant being slow crack growth (SCG). Short-term mechanical tests such as tensile, quick burst, melt index, and density tests did not show a correlation with a material's susceptibility to SCG failure. The bend-back test was able to visually identify 1971 low-ductile inner wall materials. PENT test failure times were reported for materials manufactured during the period1972-1985. The PENT test did not show correlations with the material's susceptibility to SCG failure for these materials. Life expectancy was determined to be a key measure of the susceptibility of PE gas pipe materials to SCG field failures. Long-term hydrostatic stress-rupture data combined with the Rate Process Method or with the Bi-Directional Shift Functions predicted the remaining life expectancy of several PE materials at 60�F average field temperature under varying loading conditions. Data showed rock impingement loads and pipe squeeze-offs can result in the greatest reduction in remaining life expectancy. Lower operating field temperatures and pressures significantly increased the predicted remaining life expectancy of PE materials. Fifty-five PE pipe samples that failed in field service were examined in the laboratory to identify the root cause of the failures. Eight of the samples underwent in-depth analysis, which included density and melts index tests and differential scanning calorimetry, infrared spectroscopy, and microscopic examination of the fracture surfaces. The samples were combined with another set of additional data resulting in 45 material, 36 procedural, 12 quality control, and 7 miscellaneous failures. A separate categorization method attributed a total of 321 failures to their respective pipe/component, with most occurring at joints. RCP in large diameter PE materials was investigated through laboratory testing. Critical pressure was determined for 6 pipe materials. The critical temperature was determined for 3 materials.
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Andrawes, Bassem, Ernesto Perez Claros, and Zige Zhang. Bond Characteristics and Experimental Behavior of Textured Epoxy-coated Rebars Used in Concrete Bridge Decks. Illinois Center for Transportation, 2022. http://dx.doi.org/10.36501/0197-9191/22-001.
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The deterioration of bridge decks is a problem typically associated with the corrosion of the reinforcing steel. This issue was partially controlled during the 1970s with the incorporation of the epoxy-coating protection system. However, research later demonstrated that the smooth surface resulting from the epoxy-coating application reduces most of the friction between the rebar and the surrounding concrete. Consequently, forces acting on the rib faces are reconfigured in such a way that the radial components increase, triggering the early development of cracks. To mitigate both the reduction of bonding and the formation of cracks, the Illinois Department of Transportation proposed a new type of coated bars: textured epoxy-coated (TEC) bars. Over the last few years, different projects have been executed to understand and improve the characteristics of TEC rebars. This report is a continuation of research performed at the University of Illinois Urbana-Champaign to evaluate the bond behavior of TEC bars. The experimental program starts by characterizing, qualitatively and quantitatively, the roughness of the TEC rebars. Next, their bond-slip interaction embedded in concrete is evaluated through pull-out tests. Finite element models of these tests are developed to validate the behavior observed as the textured reinforcement loses anchorage with concrete. Based on these results, the experimental program then aims to study the impact of the drying shrinkage, temperature change, and flexural demands on two large-scale bridge deck specimens reinforced, individually, with TEC and standard epoxy-coated bars. The results collected from both specimens using digital image correlation and strain gauges are compared to explore the differences exhibited by the traditional and the new type of reinforcement coatings in terms of stress distribution in bridge decks. Finally, given the specialized equipment and time-consuming procedure needed to calculate the roughness parameters of TEC bars, an empirical, weight-based approach is developed as a rapid method for assessing the rebars’ roughness on-site.
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ON FIELD-MEASURED VERTICAL TEMPERATURE GRADIENT OF BOX GIRDER IN STEEL BRIDGES. The Hong Kong Institute of Steel Construction, 2022. http://dx.doi.org/10.18057/icass2020.p.320.
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To investigate distribution of the vertical temperature gradient of a closed steel box girder under solar radiation, specifications in four major codes on the vertical temperature gradient of a main girder or steel box girder in China and other countries are first compared. Then, temperature measurement is carried out inside a steel box girder bridge. It was found that under the effect of hot weather and strong solar radiation, the temperature rose rapidly on the deck overlay and reached its maximum at around 14:00, while the maximum temperature of the deck was recorded at around 16:00. Notable temperature differences between the deck and bottom plate occurred from 14:00 to 18:00, with the maximum value of 16.8℃ presented at around 14:30. It was also found that the positive vertical temperature gradient showed nonlinear distribution, and the girder top had a larger positive temperature difference but a minor negative temperature difference. A suggested pattern of vertical temperature gradient was fitted using a four-broken-line, which is in line with specification in the Eurocode 1.
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INVESTIGATION ON BEHAVIOR OF STEEL CABLES SUBJECT TO LOCALIZED FIRE IN LARGE-SPACE BUILDINGS. The Hong Kong Institute of Steel Construction, 2024. http://dx.doi.org/10.18057/ijasc.2024.20.1.1.
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Pre-tensioned steel cable is a crucial load-bearing component of steel structure, the fire behavior of which affects the overall performance of the structure. However, it presently lacks research and fire safety design method to consider steel cable members subject to localized large-space building fire. In this paper, the mechanical behavior of normal steel strand cable and full-locked steel cable under large-space building fire is investigated, to provide guidance for the fire safety design of steel cable. Firstly, the numerical model of temperature field of steel cables subject to large-space building fire was established and verified with the test results. Secondly, based on the verified temperature field model, the sequential thermal-mechanical coupling numerical model was established to study the fire behavior of steel cable, including temperature field, temperature gradient, failure mechanism, internal force and contact stress. Thirdly, the numerical method was adopted for the parametric analysis on the fire resistance of steel cables, considering the effect of temperature-field model, non-uniform fire, load ratio and span of steel cable. The following conclusions are obtained: 1) The average temperature can be taken to simplify the transverse temperature field due to the small amplitude of transverse temperature gradient of steel cable section; 2) Because of the size effect of steel wire, the overall temperature of normal steel strand cable is higher than that of full-locked steel cable under the same conditions of same nominal diameter and fire conditions, and the damage occurs earlier than that of full-locked steel cable under fire.
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BENDING ANALYSIS OF RECYCLED CONCRETE BEAMS REINFORCED WITH GFRP BARS UNDER HIGH TEMPERATURE. The Hong Kong Institute of Steel Construction, 2024. http://dx.doi.org/10.18057/ijasc.2024.20.3.8.
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GFRP (Fiber Reinforced Polymer) reinforcement material is characterized by high strength and excellent corrosion resistance, which exhibits promising application prospects in engineering. The GFRP reinforcement for steel-concrete beams can increase the structural load-bearing capacity and durability. In this study, a refined finite element model of high-temperature GFRP-reinforced recycled steel-concrete beams was established by using ABAQUS software. The temperature distribution and residual load-carrying capacity of GFRP-reinforced recycled steel-concrete beams were analyzed, and the reliability of the model was validated based on the results of full-scale experiments on 16 groups of recycled steel-concrete beams. By using the validated model, the influence of heating temperature, reinforcement strength, steel strength, strengthening method, and concrete strength on the residual load-carrying capacity of the structure was analyzed. The stress patterns and failure mechanisms of GFRP-reinforced recycled steel-concrete beams were also analyzed. As can be seen from the results, the Type II strengthening method significantly increased the load-carrying capacity of recycled steel-concrete beams. It was also found that the load-carrying capacity of the tested beams was greatly affected by temperature. Under the temperature of 200℃ and 600℃, the load-carrying capacity of the unreinforced specimens decreases by approximately 13% and around 25%, respectively. Under the same heating temperature, compared to the unreinforced specimens, the load-carrying capacity was increased by approximately 10% by using the Type I strengthening method, but only around 4.7% by the Type II strengthening method. Finally, based on the results of this study and existing relevant experimental and numerical simulation results, and considering its feasibility and effectiveness, the Type I strengthening method for reinforced recycled steel-concrete beams was proposed. In general, the research findings of this paper can provide theoretical support for the design of reinforced recycled steel-concrete beams.