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Sample records for heat treatment induces

  1. Measurement of heat treatment induced residual stresses by using ESPI combined with hole-drilling method

    Directory of Open Access Journals (Sweden)

    Jie Cheng

    2010-08-01

    Full Text Available In this study, residual stresses in heat treated specimen were measured by using ESPI (Electronic Speckle-Pattern Interferometry combined with the hole-drilling method. The specimen, made of SUS 304 austenitic stainless steel, was quenched and water cooled to room temperature. Numerical simulation using a hybrid FDM/FEM package was also carried out to simulate the heat treatment process. As a result, the thermal stress fields were obtained from both the experiment and the numerical simulation. By comparision of stress fields, results from the experimental method and numerical simulation well agreed to each other, therefore, it is proved that the presented experimental method is applicable and reliable for heat treatment induced residual stress measurement.

  2. Heat-induced alterations in the cell nucleus

    International Nuclear Information System (INIS)

    Kampinga, H.H.

    1989-01-01

    Hyperthermia may kill eukaryotic cells and may also enhance the radiosensitivity of those cells that survive the heat treatment. Clinically, the possible use of hyperthermia as an adjuvant in the radiotherapeutic treatment of cancer needs the understanding of mechanisms that underlay heat-induced cell death and radiosensitization. By in vitro heating of established human (HeLaS3) and rodent (Ehrlich Ascites Tumor and LM fibroblast) cell lines, both killing and radiosensitization were investigated. (author). 1067 refs.; 76 figs.; 19 tabs

  3. Solar-simulated radiation and heat treatment induced metalloproteinase-1 expression in cultured dermal fibroblasts via distinct pathways: implications on reduction of sun-associated aging.

    Science.gov (United States)

    Lan, Cheng-Che E; Wu, Ching-Shang; Yu, Hsin-Su

    2013-12-01

    Sun exposure is an important environmental factor affecting human beings. Most knowledge regarding solar aging focused on light radiation (photoaging), and little emphasis has been placed on heat, a factor that is also closely associated with sun exposure. This study was launched to evaluate the effects of simulated solar radiation (SSR) and environmental heat on skin fibroblasts in terms of dermal aging. Cultured human dermal fibroblasts were treated with moderate amount of SSR (200J/cm(2)) and heat (+2°C). The metalloproteinase-1 (MMP-1) expression was used as a surrogate marker for dermal aging and the involved regulatory mechanisms were explored. Both treatment conditions did not affect viability but significantly increased the expressions of MMP-1. In parallel, both treatments increased the intracellular levels of reactive oxygen species (ROS), but the increase induced by SSR is much greater than heat. In contrast, transient receptor potential vanilloid 1 (TRPV-1), the sensor of environmental heat, was upregulated by heat but not SSR treatment. Pretreating fibroblasts with antioxidant abrogated the SSR-induced MMP-1 but has limited effect on heat-induced MMP-1. On the other hand, TRPV-1 antagonist pretreatment reduced heat-induced MMP-1 in fibroblasts but not their SSR-treated counterparts. Both SSR and heat induced MMP-1 expression in dermal fibroblasts but through different pathways. As current strategies for reducing sun-related aging focused on filtering of light and use of antioxidants, future strategies design to reduce solar aging should also incorporate heat-induced aging into consideration. Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  4. A Rice CaMBP Gene is Induced in Organ-Specific Manner by Both Chilling and Heat-Shock Treatments

    Directory of Open Access Journals (Sweden)

    Jia WAN

    2008-09-01

    Full Text Available A rice CaMBP gene, OsCaMBP (AB363406, was isolated from a chilling treated rice using the fluorescent differential display (FDD screening method. Its cDNA sequence (2094 bp contains an opening reading frame (ORF encoding a 569 amino acids protein (63.2 kD. OsCaMBP has the typical structural features of the CaMBP family, including the conserved IQ calmodulin-binding motif at the N-terminus. Homology analysis revealed 38.25%–47.28% identities of OsCaMBP with other CaMBPs in plants. RT-PCR analysis showed that the expression of OsCaMBP was remarkably inducible under the chilling (8°C and heat-shock (42°C treatments. OsCaMBP was undetectable under the normal conditions, and induced under the chilling treatment for 1 h, as well as the heat-shock treatment for 15 min, suggesting that the gene plays important roles in the signaling pathway in rice under both chilling and heat-shock stresses.

  5. 3D numerical modeling of coupled phenomena in induced processes of heat treatment with malice

    Directory of Open Access Journals (Sweden)

    Triwong Peeteenut

    2008-01-01

    Full Text Available This paper describes a multi-method Malice package for three dimension coupled phenomena in induced processes of heat treatment by an algorithm weakly coupled with the Migen package integral method defining the electromagnetic model and the Flux-Expert package finite element method defining the thermal model. The integral method is well suited to inductive systems undergoing sinusoidal excitation at midrange or high frequency. The unknowns of both models are current density, scalar potential and temperature. Joule power in the electromagnetic model is generated by Eddy currents. It becomes the heat source in the thermal model.

  6. Effects of Pressure, Temperature, Treatment Time, and Storage on Rheological, Textural, and Structural Properties of Heat-Induced Chickpea Gels

    Directory of Open Access Journals (Sweden)

    María Dolores Alvarez

    2015-04-01

    Full Text Available Pressure-induced gelatinization of chickpea flour (CF was studied in combination with subsequent temperature-induced gelatinization. CF slurries (with 1:5 flour-to-water ratio and CF in powder form were treated with high hydrostatic pressure (HHP, temperature (T, and treatment time (t at three levels (200, 400, 600 MPa; 10, 25, 50 °C; 5, 15, 25 min. In order to investigate the effect of storage (S, half of the HHP-treated CF slurries were immediately analyzed for changes in oscillatory rheological properties under isothermal heating at 75 °C for 15 min followed by cooling to 25 °C. The other half of the HHP-treated CF slurries were refrigerated (at 4 °C for one week and subsequently analyzed for changes in oscillatory properties under the same heating conditions as the unrefrigerated samples. HHP-treated CF in powder form was analyzed for changes in textural properties of heat-induced CF gels under isothermal heating at 90 °C for 5 min and subsequent cooling to 25 °C. Structural changes during gelatinization were investigated using microscopy. Pressure had a more significant effect on rheological and textural properties, followed by T and treatment t (in that order. Gel aging in HHP-treated CF slurries during storage was supported by rheological measurements.

  7. Tempo enhances heat-induced apoptosis by mitochondrial targeting of Bax

    International Nuclear Information System (INIS)

    Zhao, Q.-L.; Fujiwara, Y.; Kondo, T.

    2003-01-01

    A stable membrane-permeable nitroxide, Tempo, exerts an SOD-like antioxidant activity against ROS. Reportedly, Tempo inhibits ROS-induced thymocyte apoptosis, while 10 mM Tempo activates JNK1 to induce apoptosis in breast cancer cells. We have observed that nontoxic 5 mM Tempo enhances suboptimal hyperthermia (44 deg C/10 min)-induced apoptosis in U937 cells. Here we report the enhancing mechanism, focusing on activation and targeting of Bax to mitochondria and cytochrome c release. Methods: U937 cells were treated with either Tempo (5 mM, 37 deg C/10 min), heating (44 deg C/10 min), or Tempo-plus-heating, washed and incubated for various times up to 6 h, until assessing apoptosis, mitochondrial potential (ΔΨ>), and amount of superoxide by flow cytometry using Annexin V-FITC/PI, TMRM, and dihydroethidium, respectively. Bax, Bcl-2 and Bcl-XL, and cytochrome c were detected by western blotting, activated Bax was by immunoprecipitation, and ATP was by a luciferase assay. Bax targeting to and cytochrome c release from mitochorndria were also detected immunocytochemically under fluorescent microscopy. Results and Discussion: Treatment of U937 cells with 5 mM Tempo for 10 min at 37 deg C or suboptimal heating (44 deg C/ 10 min) alone did not induce apoptosis. The combined treatment with 5 mM Tempo and 44 deg C for 10 min dramatically induced ∼90% apoptosis in 6 h, as did the 44 deg C/30 min heating. During the enhanced apoptosis, cytochrome c release progressed. Although signals of Bcl-2, Bcl-XL and Bax in cell lysates were not altered, Bax was specifically activated and translocated to mitochondria after the combined treatment. Further, loss of ΔΨ>and decreases in superoxide and ATP progressed after the combined treatment, suggesting that the treatment may disturb mitochondrial electron transport. Thus, Tempo sensitizes the heat-induced apoptosis through (1) targeting of Bax to mitochondria and releasing cytochrome c, and (2) mitochondrial dysfunction

  8. Heat stroke induced cerebellar dysfunction: A “forgotten syndrome”

    Science.gov (United States)

    Kosgallana, Athula D; Mallik, Shreyashee; Patel, Vishal; Beran, Roy G

    2013-01-01

    We report a case of heat stroke induced acute cerebellar dysfunction, a rare neurological disease characterized by gross cerebellar dysfunction with no acute radiographic changes, in a 61 years old ship captain presenting with slurred speech and gait ataxia. A systematic review of the literature on heat stroke induced cerebellar dysfunction was performed, with a focus on investigations, treatment and outcomes. After review of the literature and detailed patient investigation it was concluded that this patient suffered heat stroke at a temperature less than that quoted in the literature. PMID:24340279

  9. Beam induced RF heating

    CERN Document Server

    Salvant, B; Arduini, G; Assmann, R; Baglin, V; Barnes, M J; Bartmann, W; Baudrenghien, P; Berrig, O; Bracco, C; Bravin, E; Bregliozzi, G; Bruce, R; Bertarelli, A; Carra, F; Cattenoz, G; Caspers, F; Claudet, S; Day, H; Garlasche, M; Gentini, L; Goddard, B; Grudiev, A; Henrist, B; Jones, R; Kononenko, O; Lanza, G; Lari, L; Mastoridis, T; Mertens, V; Métral, E; Mounet, N; Muller, J E; Nosych, A A; Nougaret, J L; Persichelli, S; Piguiet, A M; Redaelli, S; Roncarolo, F; Rumolo, G; Salvachua, B; Sapinski, M; Schmidt, R; Shaposhnikova, E; Tavian, L; Timmins, M; Uythoven, J; Vidal, A; Wenninger, J; Wollmann, D; Zerlauth, M

    2012-01-01

    After the 2011 run, actions were put in place during the 2011/2012 winter stop to limit beam induced radio frequency (RF) heating of LHC components. However, some components could not be changed during this short stop and continued to represent a limitation throughout 2012. In addition, the stored beam intensity increased in 2012 and the temperature of certain components became critical. In this contribution, the beam induced heating limitations for 2012 and the expected beam induced heating limitations for the restart after the Long Shutdown 1 (LS1) will be compiled. The expected consequences of running with 25 ns or 50 ns bunch spacing will be detailed, as well as the consequences of running with shorter bunch length. Finally, actions on hardware or beam parameters to monitor and mitigate the impact of beam induced heating to LHC operation after LS1 will be discussed.

  10. Transient, heat-induced thermal resistance in the small intestine of mouse

    International Nuclear Information System (INIS)

    Hume, S.P.; Marigold, J.C.L.

    1980-01-01

    Heat-induced thermal resistance has been investigated in mouse jejunum by assaying crypt survival 24 h after treatment. Hyperthermia was achieved by immersing an exteriorized loop of intestine in a bath of Krebs-Ringer solution. Two approaches have been used. In the first, thermal survival curves were obtained following single hyperthermal treatments at temperatures in the range 42 to 44 0 C. Transient thermal resistance, inducted by a plateau in the crypt survival curve, developed during heating at temperatures around 42.5 0 C after 60 to 80 min. In the second series of experiments, a priming heat treatment (40.0, 41.0, 41.5, or 42.0 0 C for 60 min) was followed at varying intervals by a test treatment at 43.0 0 C. A transient resistance to the second treatment was induced, the extent and time of development being dependent upon the priming treatment. Crypt survival curves for thermally resistant intestine showed an increase in thermal D 0 and a decrease in n compared with curves from previously unheated intestine

  11. [Suppressive Effects of Extract of Cedar Wood on Heat-induced Expression of Cellular Heat Shock Protein].

    Science.gov (United States)

    Miyakoshi, Junji; Matsubara, Eri; Narita, Eijiro; Koyama, Shin; Shimizu, Yoko; Kawai, Shuichi

    2018-01-01

     In recent years, highly antimicrobial properties of cedar heartwood essential oil against the wood-rotting fungi and pathogenic fungi have been reported in several papers. Antimicrobial properties against oral bacteria by hinokitiol contained in Thujopsis have been also extensively studied. The relation of naturally derived components and human immune system has been studied in some previous papers. In the present study, we focused on Japanese cedar, which has the widest artificial afforestation site in the country among various tree species. Extract oil was obtained from mixture of sapwood and heartwood of about 40-year cedar grown in Oguni, Kumamoto, Japan. We examined the influence of extract components from Japanese cedar woods on the expression of heat shock protein 70 (Hsp70) during heating, and on the micronucleus formation induced by the treatment of bleomycin as a DNA damaging agent. Cell lines used in this study were human fetal glial cells (SVGp12) and human glioma cells (MO54). Remarkable suppression of the Hsp70 expression induced by heating at 43°C was detected by the treatment of cedar extract in both SVGp12 and MO54 cells. We also found that cedar extract had an inhibitory tendency to reduce the micronucleus formation induced by bleomycin. From these results, the extract components from Japanese cedar woods would have an inhibitory effect of the stress response as a suppression of the heat-induced Hsp70 expression, and might have a reductive effect on carcinogenicity.

  12. The long-term effects of a life-prolonging heat treatment on the Drosophila melanogaster transcriptome suggest that heat shock proteins extend lifespan

    DEFF Research Database (Denmark)

    Sarup, Pernille Merete; Sørensen, Peter; Loeschcke, Volker

    2014-01-01

    Heat-induced hormesis, i.e. the beneficial effect of mild heat-induced stress, increases the average lifespan of many organisms. This effect, which depends on the heat shock factor, decreases the log mortality rate weeks after the stress has ceased. To identify candidate genes that mediate......-treated flies. Several hsp70 probe sets were up-regulated 1.7–2-fold in the mildly stressed flies weeks after the last heat treatment (P shock protein, Hsp70, is reported to return to normal levels of expression shortly after heat stress. We...... conclude that the heat shock response, and Hsp70 in particular, may be central to the heat-induced increase in the average lifespan in flies that are exposed to mild heat stress early in life....

  13. Milk protein-gum tragacanth mixed gels: effect of heat-treatment sequence.

    Science.gov (United States)

    Hatami, Masoud; Nejatian, Mohammad; Mohammadifar, Mohammad Amin; Pourmand, Hanieh

    2014-01-30

    The aim of this study was to investigate the role of the heat-treatment sequence of biopolymer mixtures as a formulation parameter on the acid-induced gelation of tri-polymeric systems composed of sodium caseinate (Na-caseinate), whey protein concentrate (WPC), and gum tragacanth (GT). This was studied by applying four sequences of heat treatment: (A) co-heating all three biopolymers; (B) heating the milk-protein dispersion and the GT dispersion separately; (C) heating the dispersion containing Na-caseinate and GT together and heating whey protein alone; and (D) co-heating whey protein with GT and heating Na-caseinate alone. According to small-deformation rheological measurements, the strength of the mixed-gel network decreased in the order: C>B>D>A samples. SEM micrographs show that the network of sample C is much more homogenous, coarse and dense than sample A, while the networks of samples B and D are of intermediate density. The heat-treatment sequence of the biopolymer mixtures as a formulation parameter thus offers an opportunity to control the microstructure and rheological properties of mixed gels. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Concept of heat-induced inkless eco-printing.

    Science.gov (United States)

    Chen, Jinxiang; Wang, Yong; Xie, Juan; Meng, Chuang; Wu, Gang; Zu, Qiao

    2012-07-01

    Existing laser and inkjet printers often produce adverse effects on human health, the recycling of printing paper and the environment. Therefore, this paper examines the thermogravimetry curves for printer paper, analyzes the discoloration of paper using heat-induction, and investigates the relationship between paper discoloration and the heat-inducing temperature. The mechanism of heat-induced printing is analyzed initially, and its feasibility is determined by a comparative analysis of heat-induced (laser ablation) printing and commercial printing. The innovative concept of heat-induced inkless eco-printing is proposed, in which the required text or graphics are formed on the printing paper via yellowing and blackening produced by thermal energy. This process does not require ink during the printing process; thus, it completely eliminates the aforementioned health and environmental issues. This research also contributes to related interdisciplinary research in biology, laser technology, photochemistry, nano-science, paper manufacturing and color science. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Effects of propofol on damage of rat intestinal epithelial cells induced by heat stress and lipopolysaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Tang, J.; Jiang, Y. [Southern Medical University, Nanfang Hospital, Department of Anesthesia, Guangzhou, China, Department of Anesthesia, Nanfang Hospital, Southern Medical University, Guangzhou (China); Tang, Y.; Chen, B. [Guangzhou General Hospital of Guangzhou Military Command, Department of Intensive Care Unit, Guangzhou, China, Department of Intensive Care Unit, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou (China); Sun, X. [Laboratory of Traditional Chinese Medicine Syndrome, School of Traditional Chinese Medicine, Southern Medical University, Guangzhou (China); Su, L.; Liu, Z. [Guangzhou General Hospital of Guangzhou Military Command, Department of Intensive Care Unit, Guangzhou, China, Department of Intensive Care Unit, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou (China)

    2013-06-25

    Gut-derived endotoxin and pathogenic bacteria have been proposed as important causative factors of morbidity and death during heat stroke. However, it is still unclear what kind of damage is induced by heat stress. In this study, the rat intestinal epithelial cell line (IEC-6) was treated with heat stress or a combination of heat stress and lipopolysaccharide (LPS). In addition, propofol, which plays an important role in anti-inflammation and organ protection, was applied to study its effects on cellular viability and apoptosis. Heat stress, LPS, or heat stress combined with LPS stimulation can all cause intestinal epithelial cell damage, including early apoptosis and subsequent necrosis. However, propofol can alleviate injuries caused by heat stress, LPS, or the combination of heat stress and LPS. Interestingly, propofol can only mitigate LPS-induced intestinal epithelial cell apoptosis, and has no protective role in heat-stress-induced apoptosis. This study developed a model that can mimic the intestinal heat stress environment. It demonstrates the effects on intestinal epithelial cell damage, and indicated that propofol could be used as a therapeutic drug for the treatment of heat-stress-induced intestinal injuries.

  16. Effects of propofol on damage of rat intestinal epithelial cells induced by heat stress and lipopolysaccharides

    International Nuclear Information System (INIS)

    Tang, J.; Jiang, Y.; Tang, Y.; Chen, B.; Sun, X.; Su, L.; Liu, Z.

    2013-01-01

    Gut-derived endotoxin and pathogenic bacteria have been proposed as important causative factors of morbidity and death during heat stroke. However, it is still unclear what kind of damage is induced by heat stress. In this study, the rat intestinal epithelial cell line (IEC-6) was treated with heat stress or a combination of heat stress and lipopolysaccharide (LPS). In addition, propofol, which plays an important role in anti-inflammation and organ protection, was applied to study its effects on cellular viability and apoptosis. Heat stress, LPS, or heat stress combined with LPS stimulation can all cause intestinal epithelial cell damage, including early apoptosis and subsequent necrosis. However, propofol can alleviate injuries caused by heat stress, LPS, or the combination of heat stress and LPS. Interestingly, propofol can only mitigate LPS-induced intestinal epithelial cell apoptosis, and has no protective role in heat-stress-induced apoptosis. This study developed a model that can mimic the intestinal heat stress environment. It demonstrates the effects on intestinal epithelial cell damage, and indicated that propofol could be used as a therapeutic drug for the treatment of heat-stress-induced intestinal injuries

  17. 29 CFR 1919.36 - Heat treatment.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Heat treatment. 1919.36 Section 1919.36 Labor Regulations...) GEAR CERTIFICATION Certification of Vessels: Tests and Proof Loads; Heat Treatment; Competent Persons § 1919.36 Heat treatment. (a) The annealing of wrought iron gear required by this part shall be...

  18. 49 CFR 179.500-6 - Heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Heat treatment. 179.500-6 Section 179.500-6...-6 Heat treatment. (a) Each necked-down tank shall be uniformly heat treated. Heat treatment shall... treatment of alternate steels shall be approved. All scale shall be removed from outside of tank to an...

  19. 29 CFR 1919.80 - Heat treatment.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Heat treatment. 1919.80 Section 1919.80 Labor Regulations...) GEAR CERTIFICATION Certification of Shore-Based Material Handling Devices § 1919.80 Heat treatment. (a) Wherever heat treatment of any loose gear is recommended by the manufacturer, it shall be carried out in...

  20. Heat Transfer Analysis of Localized Heat-Treatment for Grade 91 Steel

    Science.gov (United States)

    Walker, Jacob D.

    Many of the projects utilizing Grade 91 steel are large in scale, therefore it is necessary to assemble on site. The assembly of the major pieces requires welding in the assembly; this drastically changes the superior mechanical properties of Grade 91 steel that it was specifically developed for. Therefore, because of the adverse effects of welding on the mechanical properties of Grade 91, it is necessary to do a localized post weld heat treatment. As with most metallic materials grade 91 steel requires a very specific heat treatment process. This process includes a specific temperature and duration at that temperature to achieve the heat treatment desired. Extensive research has been done to determine the proper temperatures and duration to provide the proper microstructure for the superior mechanical properties that are inherent to Grade 91 steel. The welded sections are typically large structures that require local heat treatments and cannot be placed in an oven. The locations of these structures vary from indoors in a controlled environment to outdoors with unpredictable environments. These environments can be controlled somewhat, however in large part the surrounding conditions are unchangeable. Therefore, there is a need to develop methods to accurately apply the surrounding conditions and geometries to a theoretical model in order to provide the proper requirements for the local heat treatment procedure. Within this requirement is the requirement to define unknowns used in the heat transfer equations so that accurate models can be produced and accurate results predicted. This study investigates experimentally and numerically the heat transfer and temperature fields of Grade 91 piping in a local heat treatment. The objective of this thesis research is to determine all of the needed heat transfer coefficients. The appropriate heat transfer coefficients are determined through the inverse heat conduction method utilizing a ceramic heat blanket. This will be done

  1. In situ heat treatment process utilizing a closed loop heating system

    Science.gov (United States)

    Vinegar, Harold J.; Nguyen, Scott Vinh

    2010-12-07

    Systems and methods for an in situ heat treatment process that utilizes a circulation system to heat one or more treatment areas are described herein. The circulation system may use a heated liquid heat transfer fluid that passes through piping in the formation to transfer heat to the formation. In some embodiments, the piping may be positioned in at least two of the wellbores.

  2. Treatment of Phlegm- and Heat-induced Insomnia by Acupuncture in 120 Cases

    Institute of Scientific and Technical Information of China (English)

    崔芮; 周德安

    2003-01-01

    @@ Clinical Data The 120 cases in this series were outpatients suffering from insomnia due to interior-stirring by phlegm-heat, ranging in age from 28 to 67 years. They were randomly divided into a treatment group and a control group.

  3. Heat shock transcription factors regulate heat induced cell death in a ...

    Indian Academy of Sciences (India)

    2007-03-29

    Mar 29, 2007 ... Heat shock transcription factors regulate heat induced cell death in a rat ... the synthesis of heat shock proteins (Hsps) which is strictly regulated by ... The lack of Hsp synthesis in these cells was due to a failure in HSF1 DNA ...

  4. 49 CFR 179.400-12 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.400-12 Section 179... and 107A) § 179.400-12 Postweld heat treatment. (a) Postweld heat treatment of the inner tank is not... be attached before postweld heat treatment. Welds securing the following need not be postweld heat...

  5. Chlorophyll loss associated with heat-induced senescence in bentgrass.

    Science.gov (United States)

    Jespersen, David; Zhang, Jing; Huang, Bingru

    2016-08-01

    Heat stress-induced leaf senescence is characterized by the loss of chlorophyll from leaf tissues. The objectives of this study were to examine genetic variations in the level of heat-induced leaf senescence in hybrids of colonial (Agrostis capillaris)×creeping bentgrass (Agrostis stolonifera) contrasting in heat tolerance, and determine whether loss of leaf chlorophyll during heat-induced leaf senescence was due to suppressed chlorophyll synthesis and/or accelerated chlorophyll degradation in the cool-season perennial grass species. Plants of two hybrid backcross genotypes ('ColxCB169' and 'ColxCB190') were exposed to heat stress (38/33°C, day/night) for 28 d in growth chambers. The analysis of turf quality, membrane stability, photochemical efficiency, and chlorophyll content demonstrated significant variations in the level of leaf senescence induced by heat stress between the two genotypes, with ColXCB169 exhibiting a lesser degree of decline in chlorophyll content, photochemical efficiency and membrane stability than ColXCB190. The assays of enzymatic activity or gene expression of several major chlorophyll-synthesizing (porphobilinogen deaminase, Mg-chelatase, protochlorophyllide-reductase) and chlorophyll-degrading enzymes (chlorophyllase, pheophytinase, and chlorophyll-degrading peroxidase) indicated heat-induced decline in leaf chlorophyll content was mainly due to accelerated chlorophyll degradation, as manifested by increased gene expression levels of chlorophyllase and pheophytinase, and the activity of pheophytinase (PPH), while chlorophyll-synthesizing genes and enzymatic activities were not differentially altered by heat stress in the two genotypes. The analysis of heat-induced leaf senescence of pph mutants of Arabidopsis further confirmed that PPH could be one enzymes that plays key roles in regulating heat-accelerated chlorophyll degradation. Further research on enzymes responsible in part for the loss of chlorophyll during heat-induced

  6. Heat-treatment and heat-to-heat variations in the fracture toughness of Alloy 718

    International Nuclear Information System (INIS)

    Mills, W.J.

    1981-07-01

    The effect of heat-treatment and heat-to-heat variations on the J Ic fracture toughness response of Alloy 718 was examined at room and elevated temperatures using the multiple-specimen R-curve technique. Six heats of alloy 718 were tested in the conventional and modified heat-treated conditions. The fracture toughness response for the modified superalloy was found to be superior to that exhibited by the conventional material. Heat-to-heat variations in the J Ic response of Alloy 718 were observed in both heat-treated conditions; the modified treatment exhibited much larger variability. The J Ic and corresponding K Ic fracture toughness values were analyzed statistically to establish minimum expected toughness, values for use in design and safety analyses. 26 refs., 10 figs., 9 tabs

  7. Selective activation of human heat shock gene transcription by nitrosourea antitumor drugs mediated by isocyanate-induced damage and activation of heat shock transcription factor.

    Science.gov (United States)

    Kroes, R A; Abravaya, K; Seidenfeld, J; Morimoto, R I

    1991-01-01

    Treatment of cultured human tumor cells with the chloroethylnitrosourea antitumor drug 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) selectively induces transcription and protein synthesis of a subset of the human heat shock or stress-induced genes (HSP90 and HSP70) with little effect on other stress genes or on expression of the c-fos, c-myc, or beta-actin genes. The active component of BCNU and related compounds appears to be the isocyanate moiety that causes carbamoylation of proteins and nucleic acids. Transcriptional activation of the human HSP70 gene by BCNU is dependent on the heat shock element and correlates with the level of heat shock transcription factor and its binding to the heat shock element in vivo. Unlike activation by heat or heavy metals, BCNU-mediated activation is strongly dependent upon new protein synthesis. This suggests that BCNU-induced, isocyanate-mediated damage to newly synthesized protein(s) may be responsible for activation of the heat shock transcription factor and increased transcription of the HSP90 and HSP70 genes. Images PMID:2052560

  8. Detailing Radio Frequency Heating Induced by Coronary Stents: A 7.0 Tesla Magnetic Resonance Study

    Science.gov (United States)

    Santoro, Davide; Winter, Lukas; Müller, Alexander; Vogt, Julia; Renz, Wolfgang; Özerdem, Celal; Grässl, Andreas; Tkachenko, Valeriy; Schulz-Menger, Jeanette; Niendorf, Thoralf

    2012-01-01

    The sensitivity gain of ultrahigh field Magnetic Resonance (UHF-MR) holds the promise to enhance spatial and temporal resolution. Such improvements could be beneficial for cardiovascular MR. However, intracoronary stents used for treatment of coronary artery disease are currently considered to be contra-indications for UHF-MR. The antenna effect induced by a stent together with RF wavelength shortening could increase local radiofrequency (RF) power deposition at 7.0 T and bears the potential to induce local heating, which might cause tissue damage. Realizing these constraints, this work examines RF heating effects of stents using electro-magnetic field (EMF) simulations and phantoms with properties that mimic myocardium. For this purpose, RF power deposition that exceeds the clinical limits was induced by a dedicated birdcage coil. Fiber optic probes and MR thermometry were applied for temperature monitoring using agarose phantoms containing copper tubes or coronary stents. The results demonstrate an agreement between RF heating induced temperature changes derived from EMF simulations versus MR thermometry. The birdcage coil tailored for RF heating was capable of irradiating power exceeding the specific-absorption rate (SAR) limits defined by the IEC guidelines by a factor of three. This setup afforded RF induced temperature changes up to +27 K in a reference phantom. The maximum extra temperature increase, induced by a copper tube or a coronary stent was less than 3 K. The coronary stents examined showed an RF heating behavior similar to a copper tube. Our results suggest that, if IEC guidelines for local/global SAR are followed, the extra RF heating induced in myocardial tissue by stents may not be significant versus the baseline heating induced by the energy deposited by a tailored cardiac transmit RF coil at 7.0 T, and may be smaller if not insignificant than the extra RF heating observed under the circumstances used in this study. PMID:23185498

  9. Detailing radio frequency heating induced by coronary stents: a 7.0 Tesla magnetic resonance study.

    Directory of Open Access Journals (Sweden)

    Davide Santoro

    Full Text Available The sensitivity gain of ultrahigh field Magnetic Resonance (UHF-MR holds the promise to enhance spatial and temporal resolution. Such improvements could be beneficial for cardiovascular MR. However, intracoronary stents used for treatment of coronary artery disease are currently considered to be contra-indications for UHF-MR. The antenna effect induced by a stent together with RF wavelength shortening could increase local radiofrequency (RF power deposition at 7.0 T and bears the potential to induce local heating, which might cause tissue damage. Realizing these constraints, this work examines RF heating effects of stents using electro-magnetic field (EMF simulations and phantoms with properties that mimic myocardium. For this purpose, RF power deposition that exceeds the clinical limits was induced by a dedicated birdcage coil. Fiber optic probes and MR thermometry were applied for temperature monitoring using agarose phantoms containing copper tubes or coronary stents. The results demonstrate an agreement between RF heating induced temperature changes derived from EMF simulations versus MR thermometry. The birdcage coil tailored for RF heating was capable of irradiating power exceeding the specific-absorption rate (SAR limits defined by the IEC guidelines by a factor of three. This setup afforded RF induced temperature changes up to +27 K in a reference phantom. The maximum extra temperature increase, induced by a copper tube or a coronary stent was less than 3 K. The coronary stents examined showed an RF heating behavior similar to a copper tube. Our results suggest that, if IEC guidelines for local/global SAR are followed, the extra RF heating induced in myocardial tissue by stents may not be significant versus the baseline heating induced by the energy deposited by a tailored cardiac transmit RF coil at 7.0 T, and may be smaller if not insignificant than the extra RF heating observed under the circumstances used in this study.

  10. 49 CFR 179.220-11 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.220-11 Section 179... Postweld heat treatment. (a) Postweld heat treatment of the inner container is not a specification requirement. (b) Postweld heat treatment of the cylindrical portions of the outer shell to which the anchorage...

  11. Experimental heat treatment of silcrete implies analogical reasoning in the Middle Stone Age.

    Science.gov (United States)

    Wadley, Lyn; Prinsloo, Linda C

    2014-05-01

    Siliceous rocks that were not heated to high temperatures during their geological formation display improved knapping qualities when they are subjected to controlled heating. Experimental heat treatment of South African silcrete, using open fires of the kind used during the Middle Stone Age, shows that the process needed careful management, notwithstanding recent arguments to the contrary. Silcrete blocks fractured when heated on the surface of open fires or on coal beds, but were heated without mishap when buried in sand below a fire. Three silcrete samples, a control, a block heated underground with maximum temperature between 400 and 500 °C and a block heated in an open fire with maximum temperature between 700 and 800 °C, were analysed with X-ray powder diffraction (XRD), X-ray fluorescence (XRF), optical microscopy, and both Fourier transform infrared (FTIR) and Raman spectroscopy. The results show that the volume expansion during the thermally induced α- to β-quartz phase transformation and the volume contraction during cooling play a major role in the heat treatment of silcrete. Rapid heating or cooling through the phase transformation at 573 °C will cause fracture of the silcrete. Successful heat treatment requires controlling surface fire temperatures in order to obtain the appropriate underground temperatures to stay below the quartz inversion temperature. Heat treatment of rocks is a transformative technology that requires skilled use of fire. This process involves analogical reasoning, which is an attribute of complex cognition. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Process for forming thin film, heat treatment process of thin film sheet, and heat treatment apparatus therefor

    International Nuclear Information System (INIS)

    Watanabe, S.

    1984-01-01

    The invention provides a process for forming a magnetic thin film on a base film, a heat treatment process of a thin film sheet consisting of the base film and the magnetic thin film, and an apparatus for performing heat treatment of the thin film sheet. Tension applied to the thin film sheet is substantially equal to that applied to the base film when the magnetic thin film is formed thereon. Then, the thin film sheet is treated with heat. The thin film sheet is heated with a given temperature gradient to a reactive temperature at which heat shrinkage occurs, while the tension is being applied thereto. Thereafter, the thin film sheet to which the tension is still applied is cooled with substantially the same temperature gradient as applied in heating. The heat treatment apparatus has a film driving unit including a supply reel, a take-up reel, a drive source and guide rollers; a heating unit including heating plates, heater blocks and a temperature controller for heating the sheet to the reactive temperature; and a heat insulating unit including a thermostat and another temperature controller for maintaining the sheet at the nonreactive temperature which is slightly lower than the reactive temperature

  13. Pre-treatment with mild whole-body heating prevents gastric ulcer induced by restraint and water-immersion stress in rats.

    Science.gov (United States)

    Itoh, Y H; Noguchi, R

    2000-01-01

    The purpose of this study was to assess the preventive effect of pre-mild whole-body heating (WBH) on gastric ulcer induced by restraint and water-immersion stress. The ulcer index and ulcer area ratio in rats exposed to restraint and water-immersion stress were significantly decreased (p immersion stress alone (p immersion, thereby preventing gastric ulcer formation. Pre-treatment with mild WBH is the safest cytoprotective method through the accumulation of HSP 70f. The concentration of HSP 70f in peripheral lymphocytes may be a useful clinical laboratory indicator for assessing the level of HSP 70f as having cytoprotective activity.

  14. Heat treatment furnace

    Science.gov (United States)

    Seals, Roland D; Parrott, Jeffrey G; DeMint, Paul D; Finney, Kevin R; Blue, Charles T

    2014-10-21

    A furnace heats through both infrared radiation and convective air utilizing an infrared/purge gas design that enables improved temperature control to enable more uniform treatment of workpieces. The furnace utilizes lamps, the electrical end connections of which are located in an enclosure outside the furnace chamber, with the lamps extending into the furnace chamber through openings in the wall of the chamber. The enclosure is purged with gas, which gas flows from the enclosure into the furnace chamber via the openings in the wall of the chamber so that the gas flows above and around the lamps and is heated to form a convective mechanism in heating parts.

  15. Plasma assisted heat treatment: annealing

    International Nuclear Information System (INIS)

    Brunatto, S F; Guimaraes, N V

    2009-01-01

    This work comprises a new dc plasma application in the metallurgical-mechanical field, called plasma assisted heat treatment, and it presents the first results for annealing. Annealing treatments were performed in 90% reduction cold-rolled niobium samples at 900 deg. C and 60 min, in two different heating ways: (a) in a hollow cathode discharge (HCD) configuration and (b) in a plasma oven configuration. The evolution of the samples' recrystallization was determined by means of the microstructure, microhardness and softening rate characterization. The results indicate that plasma species (ions and neutrals) bombardment in HCD plays an important role in the recrystallization process activation and could lead to technological and economical advantages considering the metallic materials' heat treatment application. (fast track communication)

  16. Finite element calculation of stress induced heating of superconductors

    International Nuclear Information System (INIS)

    Akin, J.E.; Moazed, A.

    1976-01-01

    This research is concerned with the calculation of the amount of heat generated due to the development of mechanical stresses in superconducting composites. An emperical equation is used to define the amount of stress-induced heat generation per unit volume. The equation relates the maximum applied stress and the experimental measured hysteresis loop of the composite stress-strain diagram. It is utilized in a finite element program to calculate the total stress-induced heat generation for the superconductor. An example analysis of a solenoid indicates that the stress-induced heating can be of the same order of magnitude as eddy current effects

  17. Intergenic sequence between Arabidopsis caseinolytic protease B-cytoplasmic/heat shock protein100 and choline kinase genes functions as a heat-inducible bidirectional promoter.

    Science.gov (United States)

    Mishra, Ratnesh Chandra; Grover, Anil

    2014-11-01

    In Arabidopsis (Arabidopsis thaliana), the At1g74310 locus encodes for caseinolytic protease B-cytoplasmic (ClpB-C)/heat shock protein100 protein (AtClpB-C), which is critical for the acquisition of thermotolerance, and At1g74320 encodes for choline kinase (AtCK2) that catalyzes the first reaction in the Kennedy pathway for phosphatidylcholine biosynthesis. Previous work has established that the knockout mutants of these genes display heat-sensitive phenotypes. While analyzing the AtClpB-C promoter and upstream genomic regions in this study, we noted that AtClpB-C and AtCK2 genes are head-to-head oriented on chromosome 1 of the Arabidopsis genome. Expression analysis showed that transcripts of these genes are rapidly induced in response to heat stress treatment. In stably transformed Arabidopsis plants harboring this intergenic sequence between head-to-head oriented green fluorescent protein and β-glucuronidase reporter genes, both transcripts and proteins of the two reporters were up-regulated upon heat stress. Four heat shock elements were noted in the intergenic region by in silico analysis. In the homozygous transfer DNA insertion mutant Salk_014505, 4,393-bp transfer DNA is inserted at position -517 upstream of ATG of the AtClpB-C gene. As a result, AtCk2 loses proximity to three of the four heat shock elements in the mutant line. Heat-inducible expression of the AtCK2 transcript was completely lost, whereas the expression of AtClpB-C was not affected in the mutant plants. Our results suggest that the 1,329-bp intergenic fragment functions as a heat-inducible bidirectional promoter and the region governing the heat inducibility is possibly shared between the two genes. We propose a model in which AtClpB-C shares its regulatory region with heat-induced choline kinase, which has a possible role in heat signaling. © 2014 American Society of Plant Biologists. All Rights Reserved.

  18. Continuous fever-range heat stress induces thermotolerance in odontoblast-lineage cells.

    Science.gov (United States)

    Morotomi, Takahiko; Kitamura, Chiaki; Okinaga, Toshinori; Nishihara, Tatsuji; Sakagami, Ryuji; Anan, Hisashi

    2014-07-01

    Heat shock during restorative procedures can trigger damage to the pulpodentin complex. While severe heat shock has toxic effects, fever-range heat stress exerts beneficial effects on several cells and tissues. In this study, we examined whether continuous fever-range heat stress (CFHS) has beneficial effects on thermotolerance in the rat clonal dental pulp cell line with odontoblastic properties, KN-3. KN-3 cells were cultured at 41°C for various periods, and the expression level of several proteins was assessed by Western blot analysis. After pre-heat-treatment at 41°C for various periods, KN-3 cells were exposed to lethal severe heat shock (LSHS) at 49°C for 10min, and cell viability was examined using the MTS assay. Additionally, the expression level of odontoblast differentiation makers in surviving cells was examined by Western blot analysis. CFHS increased the expression levels of several heat shock proteins (HSPs) in KN-3 cells, and induced transient cell cycle arrest. KN-3 cells, not pre-heated or exposed to CFHS for 1 or 3h, died after exposure to LSHS. In contrast, KN-3 cells exposed to CFHS for 12h were transiently lower on day 1, but increased on day 3 after LSHS. The surviving cells expressed odontoblast differentiation markers, dentine sialoprotein and dentine matrix protein-1. These results suggest that CFHS for 12h improves tolerance to LSHS by inducing HSPs expression and cell cycle arrest in KN-3 cells. The appropriate pretreatment with continuous fever-range heat stress can provide protection against lethal heat shock in KN-3 cells. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Spectroscopic analysis of the role of extractives on heat-induced discoloration of black locust (Robinia pseudoacacia)

    Science.gov (United States)

    Yao Chen; Yongming Fan; Jianmin Gao; Mandla A. Tshabalala; Nicole M. Stark

    2012-01-01

    To investigate the role of extractives on heat-induced discoloration of wood, samples of black locust (Robinia pseudoacacia) wood flour were extracted with various solvents prior to heat-treatment. Analysis of their color parameters and chromophoric structures showed that the chroma value of the unextracted sample decreased while that of the...

  20. Advances in the heat treatment of steels

    International Nuclear Information System (INIS)

    Morris, J.W. Jr.; Kim, J.I.; Syn, C.K.

    1978-06-01

    A number of important recent advances in the processing of steels have resulted from the sophisticated uses of heat treatment to tailor the microstructure of the steels so that desirable properties are established. These new heat treatments often involve the tempering or annealing of the steel to accompish a partial or complete reversion from martensite to austenite. The influence of these reversion heat treatments on the product microstructure and its properties may be systematically discussed in terms of the heat treating temperature in relation to the phase diagram. From this perspective, four characteristic heat treatments are defined: (1) normal tempering, (2) inter-critical tempering, (3) intercritical annealing, and (4) austenite reversion. The reactions occurring during each of these treatments are described and the nature and properties of typical product microstructures discussed, with specific reference to new commercial or laboratory steels having useful and exceptional properties

  1. Mild heat treatments induce long-term changes in metabolites associated with energy metabolism in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Sarup, Pernille; Petersen, Simon Metz Mariendal; Nielsen, Niels Christian

    2016-01-01

    treatments on the metabolome of male Drosophila melanogaster. 10 days after the heat treatment, metabolic aging appears to be slowed down, and a treatment response with 40 % higher levels of alanine and lactate and lower levels of aspartate and glutamate were measured. All treatment effects had disappeared...

  2. MATHEMATICAL MODELING OF HEATING RATE PRODUCT AT HIGH HEAT TREATMENT

    Directory of Open Access Journals (Sweden)

    M. M. Akhmedova

    2014-01-01

    Full Text Available Methods of computing and mathematical modeling are all widely used in the study of various heat exchange processes that provide the ability to study the dynamics of the processes, as well as to conduct a reasonable search for the optimal technological parameters of heat treatment.This work is devoted to the identification of correlations among the factors that have the greatest effect on the rate of heating of the product at hightemperature heat sterilization in a stream of hot air, which are chosen as the temperature difference (between the most and least warming up points and speed cans during heat sterilization.As a result of the experimental data warming of the central and peripheral layers compote of apples in a 3 liter pot at high-temperature heat treatment in a stream of hot air obtained by the regression equation in the form of a seconddegree polynomial, taking into account the effects of pair interaction of these parameters. 

  3. Insights into the Molecular Events That Regulate Heat-Induced Chilling Tolerance in Citrus Fruits.

    Science.gov (United States)

    Lafuente, María T; Establés-Ortíz, Beatriz; González-Candelas, Luis

    2017-01-01

    Low non-freezing temperature may cause chilling injury (CI), which is responsible for external quality deterioration in many chilling-sensitive horticultural crops. Exposure of chilling-sensitive citrus cultivars to non-lethal high-temperature conditioning may increase their chilling tolerance. Very little information is available about the molecular events involved in such tolerance. In this work, the molecular events associated with the low temperature tolerance induced by heating Fortune mandarin, which is very sensitive to chilling, for 3 days at 37°C prior to cold storage is presented. A transcriptomic analysis reveals that heat-conditioning has an important impact favoring the repression of genes in cold-stored fruit, and that long-term heat-induced chilling tolerance is an active process that requires activation of transcription factors involved in transcription initiation and of the WRKY family. The analysis also shows that chilling favors degradation processes, which affect lipids and proteins, and that the protective effect of the heat-conditioning treatment is more likely to be related to the repression of the genes involved in lipid degradation than to the modification of fatty acids unsaturation, which affects membrane permeability. Another major factor associated with the beneficial effect of the heat treatment on reducing CI is the regulation of stress-related proteins. Many of the genes that encoded such proteins are involved in secondary metabolism and in oxidative stress-related processes.

  4. Insights into the Molecular Events That Regulate Heat-Induced Chilling Tolerance in Citrus Fruits

    Directory of Open Access Journals (Sweden)

    María T. Lafuente

    2017-06-01

    Full Text Available Low non-freezing temperature may cause chilling injury (CI, which is responsible for external quality deterioration in many chilling-sensitive horticultural crops. Exposure of chilling-sensitive citrus cultivars to non-lethal high-temperature conditioning may increase their chilling tolerance. Very little information is available about the molecular events involved in such tolerance. In this work, the molecular events associated with the low temperature tolerance induced by heating Fortune mandarin, which is very sensitive to chilling, for 3 days at 37°C prior to cold storage is presented. A transcriptomic analysis reveals that heat-conditioning has an important impact favoring the repression of genes in cold-stored fruit, and that long-term heat-induced chilling tolerance is an active process that requires activation of transcription factors involved in transcription initiation and of the WRKY family. The analysis also shows that chilling favors degradation processes, which affect lipids and proteins, and that the protective effect of the heat-conditioning treatment is more likely to be related to the repression of the genes involved in lipid degradation than to the modification of fatty acids unsaturation, which affects membrane permeability. Another major factor associated with the beneficial effect of the heat treatment on reducing CI is the regulation of stress-related proteins. Many of the genes that encoded such proteins are involved in secondary metabolism and in oxidative stress-related processes.

  5. 29 CFR 1919.16 - Heat treatment.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Heat treatment. 1919.16 Section 1919.16 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) GEAR CERTIFICATION Certification of Vessels' Cargo Gear § 1919.16 Heat treatment. (a) All chains (other...

  6. 49 CFR 179.200-11 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.200-11 Section 179.200-11 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Postweld heat treatment. When specified in § 179.201-1, after welding is complete, postweld heat treatment...

  7. FTIR study of aquamarines after gamma irradiation, heat treatment and electrodiffusion

    International Nuclear Information System (INIS)

    Alkmim, Danielle Gomides; Almeida, Frederico Ozanan Tomaz de; Lameiras, Fernando Soares

    2017-01-01

    Beryl, Be_3Al_2(SiO_3)_6, is a natural gemstone with many colors. Some of these colors can be induced or modified by exposure to ionizing radiation, by heating, and maybe by electrodiffusion. Small contents of chromophore chemical elements are related to the colors of beryl, like iron, chromium, vanadium, manganese, and others. There is great interest in relation to methods of improving or inducing colors in beryl. There is evidence that infrared spectroscopy (FTIR) can contribute to foresee beryl behavior submitted to procedures for color change. It was observed that electrodiffusion with or without contaminant ions did not alter the FTIR spectrum of aquamarines, unlike heat treatment. Green samples have a higher content of type I water molecules, whereas blue samples have a higher content of type II water molecules. Significant changes in FTIR spectra of aquamarines were observed only in green samples after exposure to gamma rays or to heat. The vanishing of the band at 3633 cm"-"1 may be related to the position of Na"+ ion in the crystal lattice of beryl. (author)

  8. FTIR study of aquamarines after gamma irradiation, heat treatment and electrodiffusion

    Directory of Open Access Journals (Sweden)

    Danielle Gomides Alkmim

    Full Text Available Abstract Beryl, Be3Al2(SiO36, is a natural gemstone with many colors. Some of these colors can be induced or modified by exposure to ionizing radiation, by heating, and maybe by electrodiffusion. Small contents of chromophore chemical elements are related to the colors of beryl, like iron, chromium, vanadium, manganese, and others. There is great interest in relation to methods of improving or inducing colors in beryl. There is evidence that infrared spectroscopy (FTIR can contribute to foresee beryl behavior submitted to procedures for color change. It was observed that electrodiffusion with or without contaminant ions did not alter the FTIR spectrum of aquamarines, unlike heat treatment. Green samples have a higher content of type I water molecules, whereas blue samples have a higher content of type II water molecules. Significant changes in FTIR spectra of aquamarines were observed only in green samples after exposure to gamma rays or to heat. The vanishing of the band at 3633 cm-1 may be related to the position of Na+ ion in the crystal lattice of beryl.

  9. Palm kernel cake extract exerts hepatoprotective activity in heat-induced oxidative stress in chicken hepatocytes.

    Science.gov (United States)

    Oskoueian, Ehsan; Abdullah, Norhani; Idrus, Zulkifli; Ebrahimi, Mahdi; Goh, Yong Meng; Shakeri, Majid; Oskoueian, Armin

    2014-10-02

    Palm kernel cake (PKC), the most abundant by-product of oil palm industry is believed to contain bioactive compounds with hepatoprotective potential. These compounds may serve as hepatoprotective agents which could help the poultry industry to alleviate adverse effects of heat stress on liver function in chickens. This study was performed to evaluate the hepatoprotective potential of PKC extract in heat-induced oxidative stress in chicken hepatocytes. The nature of the active metabolites and elucidation of the possible mechanism involved were also investigated. The PKC extract possessed free radical scavenging activity with values significantly (p < 0.05) lower than silymarin as the reference antioxidant. Heat-induced oxidative stress in chicken hepatocyte impaired the total protein, lipid peroxidation and antioxidant enzymes activity significantly (p < 0.05). Treatment of heat-induced hepatocytes with PKC extract (125 μg/ml) and silymarin as positive control increased these values significantly (p < 0.05). The real time PCR and western blot analyses revealed the significant (p < 0.05) up-regulation of oxidative stress biomarkers including TNF-like, IFN-γ and IL-1β genes; NF-κB, COX-2, iNOS and Hsp70 proteins expression upon heat stress in chicken hepatocytes. The PKC extract and silymarin were able to alleviate the expression of all of these biomarkers in heat-induced chicken hepatocytes. The gas chromatography-mass spectrometry analysis of PKC extract showed the presence of fatty acids, phenolic compounds, sugar derivatives and other organic compounds such as furfural which could be responsible for the observed hepatoprotective activity. Palm kernel cake extract could be a potential agent to protect hepatocytes function under heat induced oxidative stress.

  10. Improved process for the treatment of bituminous materials. [two heat treatments

    Energy Technology Data Exchange (ETDEWEB)

    1947-04-30

    A continuous process for recovering valuable hydrocarbon oils from solid minerals adapted to produce such oils upon application of heat, consists of reducing the raw minerals to a powder, suspending the powdered minerals in a gaseous medium and subjecting the suspension thus formed to heat treatment in a primary reaction zone, followed by heat treatment in a secondary reaction zone separate from the primary reaction zone. The temperature during the second of said treatments being substantially higher than that of the first.

  11. Heat Stress-Induced PI3K/mTORC2-Dependent AKT Signaling Is a Central Mediator of Hepatocellular Carcinoma Survival to Thermal Ablation Induced Heat Stress.

    Directory of Open Access Journals (Sweden)

    Scott M Thompson

    Full Text Available Thermal ablative therapies are important treatment options in the multidisciplinary care of patients with hepatocellular carcinoma (HCC, but lesions larger than 2-3 cm are plagued with high local recurrence rates and overall survival of these patients remains poor. Currently no adjuvant therapies exist to prevent local HCC recurrence in patients undergoing thermal ablation. The molecular mechanisms mediating HCC resistance to thermal ablation induced heat stress and local recurrence remain unclear. Here we demonstrate that the HCC cells with a poor prognostic hepatic stem cell subtype (Subtype HS are more resistant to heat stress than HCC cells with a better prognostic hepatocyte subtype (Subtype HC. Moreover, sublethal heat stress rapidly induces phosphoinositide 3-kinase (PI3K/mammalian target of rapamycin (mTOR dependent-protein kinase B (AKT survival signaling in HCC cells in vitro and at the tumor ablation margin in vivo. Conversely, inhibition of PI3K/mTOR complex 2 (mTORC2-dependent AKT phosphorylation or direct inhibition of AKT function both enhance HCC cell killing and decrease HCC cell survival to sublethal heat stress in both poor and better prognostic HCC subtypes while mTOR complex 1 (mTORC1-inhibition has no impact. Finally, we showed that AKT isoforms 1, 2 and 3 are differentially upregulated in primary human HCCs and that overexpression of AKT correlates with worse tumor biology and pathologic features (AKT3 and prognosis (AKT1. Together these findings define a novel molecular mechanism whereby heat stress induces PI3K/mTORC2-dependent AKT survival signaling in HCC cells and provide a mechanistic rationale for adjuvant AKT inhibition in combination with thermal ablation as a strategy to enhance HCC cell killing and prevent local recurrence, particularly at the ablation margin.

  12. Effect of Heat Shock Treatment and Aloe Vera Coating to Chilling Injury Symptom in Tomato (Lycopersicon asculantum Mill.

    Directory of Open Access Journals (Sweden)

    Sutrisno

    2012-04-01

    Full Text Available This research was undertaken to determine the effect of length in heat shock and edible coating as pre-storage treatment to Chilling Injury (CI symptom reflected by ion leakage induced and quality properties in tomato (Lycopersicon asculantum Mill.. Heat Shock Treatment (HST was conducted at three different levels of length, which were, 20; 40 and 60 min. Edible coating was conducted using aloe vera gel. The result showed that HST and Aloe Vera Coating (AVC were more effective to reduce CI symptom at lower chilling storage. Prolong exposure to heated water may delay climacteric peak. The length of heat shock, AVC treatment and low temperature storage significantly affected the tomato quality parameter but not significantly different for each treatment except weight loss. HST for 20 min at ambient temperature was significantly different to other treatment.

  13. Geldanamycin induces heat shock protein 70 and protects against MPTP-induced dopaminergic neurotoxicity in mice.

    Science.gov (United States)

    Shen, Hai-Ying; He, Jin-Cai; Wang, Yumei; Huang, Qing-Yuan; Chen, Jiang-Fan

    2005-12-02

    As key molecular chaperone proteins, heat shock proteins (HSPs) represent an important cellular protective mechanism against neuronal cell death in various models of neurological disorders. In this study, we investigated the effect as well as the molecular mechanism of geldanamycin (GA), an inhibitor of Hsp90, on 1-methyl-4-pheny-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic neurotoxicity, a mouse model of Parkinson disease. Neurochemical analysis showed that pretreatment with GA (via intracerebral ventricular injection 24 h prior to MPTP treatment) increased residual dopamine content and tyrosine hydroxylase immunoreactivity in the striatum 24 h after MPTP treatment. To dissect out the molecular mechanism underlying this neuroprotection, we showed that the GA-mediated protection against MPTP was associated with a reduction of cytosolic Hsp90 and an increase in Hsp70, with no significant changes in Hsp40 and Hsp25 levels. Furthermore, in parallel with the induction of Hsp70, striatal nuclear HSF1 levels and HSF1 binding to heat shock element sites in the Hsp70 promoter were significantly enhanced by the GA pretreatment. Together these results suggested that the molecular cascade leading to the induction of Hsp70 is critical to the neuroprotection afforded by GA against MPTP-induced neurotoxicity in the brain and that pharmacological inhibition of Hsp90 may represent a potential therapeutic strategy for Parkinson disease.

  14. Structural changes in deashed coals induced by heat treatment; Kanetsu shori ni yoru dakkaitan no kozo henka

    Energy Technology Data Exchange (ETDEWEB)

    Sugano, M.; Sekita, M.; Muramatsu, Y.; Mashimo, K.; Wainai, T. [Nihon University, Tokyo (Japan). College of Science and Technology

    1996-10-28

    Change in structures of 3 kinds of coals with different coal ranks and their deashed coals was studied by heat treatment below 200{degree}C. In experiment, crushed Adaro, Taiheiyo and Huaibei coals below 200mesh and their deashed coals were used as specimens. The coal and deashed coal specimens dried in vacuum at 110{degree}C for 3 hours were filled into an autoclave, and the heat-treated coal specimens were prepared by holding them under initial nitrogen pressure of 2kg/cm{sup 2} at a fixed temperature for 30min. Extraction using pyridine as solvent, volumetric swelling using methanol or benzene as solvent, and measurement of the amount of carboxyl and phenolic hydroxyl functional groups were conducted for these coal specimens. The experimental results are as follows. Huaibei coal has developed aromatic ring structure, and its structure is hardly affected by heat treatment. The oxygen containing functional groups decrease by heat treatment over 100{degree}C in Adaro coal and 150{degree}C in Taiheiyo coal, and PS, MQ and BQ also decrease due to aggregation between molecules. 5 refs., 2 figs.

  15. Sensitization by wortmannin of heat- or X-ray induced cell death in cultured Chinese hamster V79 cells

    International Nuclear Information System (INIS)

    Tomita, Masanori; Suzuki, Norio; Matsumoto, Yoshihisa; Hirano, Kazuya; Umeda, Noriko; Sakai, Kazuo

    2000-01-01

    Here we found that wortmannin sensitized Chinese hamster V79 cells to hyperthermic treatment at 44.0 deg C as determined either by colony formation assay or by dye exclusion assay. Wortmannin enhanced heat-induced cell death accompanying cleavage of poly (ADP-ribose) polymerases (PARP). Additionally, the induction of heat shock protein HSP70 was suppressed and delayed in wortmannin-treated cells. Heat sensitizing effect of wortmannin was obvious at more than 5 or 10 μM of final concentrations, while radiosensitization was apparent at 5 μM. Requirement for high concentration of wortmannin, i.e., order of μM, suggests a possible role of certain protein kinases, such as DNA-PK and/or ATM among PI3-kinase family. The sensitization was minimal when wortmannin was added at the end of heat treatment. This was similar to the case of X-ray. Since heat-induced cell death and PARP cleavage preceded HSP70 induction phenomenon, the sensitization to the hyperthermic treatment was considered mainly caused by enhanced apoptotic cell death rather than secondary to suppression or delay by wortmannin of HSP70 induction. Further, in the present system radiosensitization by wortmannin was also at least partly mediated through enhancement of apoptotic cell death. (author)

  16. Prostaglandins with antiproliferative activity induce the synthesis of a heat shock protein in human cells

    International Nuclear Information System (INIS)

    Santoro, M.G.; Garaci, E.; Amici, C.

    1989-01-01

    Prostaglandins (PGs)A 1 and J 2 were found to potently suppress the proliferation of human K562 erythroleukemia cells and to induce the synthesis of a 74-kDa protein (p74) that was identified as a heat shock protein related to the major 70-kDa heat shock protein group. p74 synthesis was stimulated at doses of PGA 1 and PGJ 2 that inhibited cell replication, and its accumulation ceased upon removal of the PG-induced proliferation block. PGs that did not affect K562 cell replication did not induce p74 synthesis. p74 was found to be localized mainly in the cytoplasm of PG-treated cells, but moderate amounts were found also in dense areas of the nucleus after PGJ 2 treatment. p74 was not necessarily associated with cytotoxicity or with inhibition of cell protein synthesis. The results described support the hypothesis that synthesis of the 70-kDa heat shock proteins is associated with changes in cell proliferation. The observation that PGs can induce the synthesis of heat shock proteins expands our understanding of the mechanism of action of these compounds whose regulatory role is well known in many physiological phenomena, including the control of fever production

  17. Characterization by transmission electron microscopy of a JRQ steel subjected to different heat treatments

    International Nuclear Information System (INIS)

    Moreno G, N.

    2014-01-01

    In this work a study was conducted on the steel Astm A-533, Grade B, Class 1 of reference JRQ, for the purpose of carrying out a study by transmission electron microscopy on the size and distribution of precipitates in steel samples JRQ previously subjected to heat treatments. This because the reactor vessels of the nuclear power plant of Laguna Verde, are made of a steel Astm A-533 Grade B, Class 1. It is known that the neutron radiation causes damage primarily embrittlement in materials that are exposed to it. However, observable damage through mechanical tests result from microstructural defects and atomic, induced by the neutron radiation. In previous studies hardening by precipitation of a JRQ steel (provided by the IAEA) was induced by heat treatments, finding that the conditions of heat treatment that reproduce the hardness and stress mechanical properties of a steel Astm A-533, Grade B, Class 1 irradiated for 8 years to a fluence of 3.5 x 10 17 neutrons/cm 2 and to a temperature of 290 grades C are achieved with annealing treatments at 550 grades C. In the studied samples it was found that the more hardening phase both the heat treatments as the neutron radiation, is the bainite, being the ferrite practically unchanged. Which it gave the tone to believe that the ferrite is the phase that provides at level macro the mechanical properties in stress, since in the irradiated samples such properties remained unchanged with respect to the non-irradiated material, however changes were observed in material ductility, which may be attributable to the change of hardness in the bainite, which opens a possibility for modeling the micromechanical behavior of this material. (Author)

  18. Effect of heat-treatment on elevated temperature fatigue-crack growth behavior of two heats of Alloy 718

    International Nuclear Information System (INIS)

    Mills, W.J.; James, L.A.

    1978-05-01

    The room temperature and elevated temperature fatigue-crack growth behavior of two heats of Alloy 718 was characterized within a linear-elastic fracture mechanics framework. Two different heat-treatments were used: the ''conventional'' (ASTM A637) treatment, and a ''modified'' heat-treatment designed to improve the toughness of Alloy 718 base metal and weldments. Heat-to-heat variations in the fatigue-crack propagation behavior were observed in the conventionally-treated material. On the other hand, no heat-to-heat variations were observed in the modified condition. Furthermore, both heats of Alloy 718 exhibited superior fatigue-crack growth resistance when given the modified heat-treatment. Electron fractographic examination of Alloy 718 fatigue fracture surfaces revealed that the operative crack growth mechanisms were dependent on heat-treatment, temperature, and ΔK level

  19. Furan: A critical heat induced dietary contaminant

    DEFF Research Database (Denmark)

    Mariotti, María S.; Granby, Kit; Rozowski, Jaime

    2013-01-01

    The presence of furan in a broad range of heat processed foods (0-6000 μg kg-1) has received considerable attention due to the fact that this heat induced contaminant is considered as a "possible carcinogenic compound to humans". Since a genotoxic mode of action could be associated with furan...... of some critical factors such as heating conditions, pH and matrix microstructure are discussed in order to propose some potential methodologies for furan mitigation in a wide range of heated foods. © 2013 The Royal Society of Chemistry....

  20. Identification of proteins whose synthesis in Saccharomyces cerevisiae is induced by DNA damage and heat shock

    International Nuclear Information System (INIS)

    Gailit, James

    1990-01-01

    Protein synthesis in Saccharomyces cerevisiae after exposure to ultraviolet light (UV) was examined by two-dimensional gel electrophoresis of pulse-labelled proteins. The synthesis of 12 distinct proteins was induced by treatment with UV doses of 10-200 J/m 2 . The induced proteins differed in minimum dose necessary for induction, maximum dose at which induction still occurred and constitutive level present in unirradiated cells. A chemical mutagen, 4-nitroquinoline-1-oxide, induced synthesis of the same proteins. Induction after UV treatment was observed in seven different yeast strains, including three mutants deficient in DNA repair. Synthesis of five of the proteins was also induced by brief heat shock treatment. These five may be members of a family of proteins whose synthesis is regulated by two different pathways responding to different types of stress. (author)

  1. Magnetic induced heating of nanoparticle solutions

    Energy Technology Data Exchange (ETDEWEB)

    Murph, S. Hunyadi [Savannah River Site (SRS), Aiken, SC (United States); Univ. of Georgia, Athens, GA (United States); Brown, M. [Savannah River Site (SRS), Aiken, SC (United States); Coopersmith, K. [Savannah River Site (SRS), Aiken, SC (United States); Fulmer, S. [Savannah River Site (SRS), Aiken, SC (United States); Sessions, H. [Savannah River Site (SRS), Aiken, SC (United States); Ali, M. [Univ. of South Carolina, Columbia, SC (United States)

    2016-12-02

    Magnetic induced heating of nanoparticles (NP) provides a useful advantage for many energy transfer applications. This study aims to gain an understanding of the key parameters responsible for maximizing the energy transfer leading to nanoparticle heating through the use of simulations and experimental results. It was found that magnetic field strength, NP concentration, NP composition, and coil size can be controlled to generate accurate temperature profiles in NP aqueous solutions.

  2. FTIR study of aquamarines after gamma irradiation, heat treatment and electrodiffusion

    Energy Technology Data Exchange (ETDEWEB)

    Alkmim, Danielle Gomides; Almeida, Frederico Ozanan Tomaz de; Lameiras, Fernando Soares, E-mail: alkmia@yahoo.com.br, E-mail: fredufmg@gmail.com, E-mail: fsl@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-15

    Beryl, Be{sub 3}Al{sub 2}(SiO{sub 3}){sub 6}, is a natural gemstone with many colors. Some of these colors can be induced or modified by exposure to ionizing radiation, by heating, and maybe by electrodiffusion. Small contents of chromophore chemical elements are related to the colors of beryl, like iron, chromium, vanadium, manganese, and others. There is great interest in relation to methods of improving or inducing colors in beryl. There is evidence that infrared spectroscopy (FTIR) can contribute to foresee beryl behavior submitted to procedures for color change. It was observed that electrodiffusion with or without contaminant ions did not alter the FTIR spectrum of aquamarines, unlike heat treatment. Green samples have a higher content of type I water molecules, whereas blue samples have a higher content of type II water molecules. Significant changes in FTIR spectra of aquamarines were observed only in green samples after exposure to gamma rays or to heat. The vanishing of the band at 3633 cm{sup -1} may be related to the position of Na{sup +} ion in the crystal lattice of beryl. (author)

  3. Microwave heat treatment as a substitute for conventional treatment of palm oil fruits

    International Nuclear Information System (INIS)

    Mujahid H Al-Fayadh; Nor Azura Masabbir Ali

    1996-01-01

    Microwave energy has become a sound method of heat treatment because of its high penetration power, cleanliness and possible economic significance. In this research, microwave heat was used as a substitute for conventional blanching method of palm oil fruits. Microwave treatment at 2450 MHz and 800 watts gave very close color and frn,frying characteristics to oil of blanched fruits after one minute exposure time. However, five minutes of microwave heat gave severe husk oil discoloration after 49 hours of deep frying, compared to all oils extracted from fruits treated by either low, microwave exposure time or conventional steam treatment. Kernel oil, after five minutes of microwave treatment, was less discolored than both steam or microwave-treated fruits for one minute. More carotenes and discoloration compounds may be contributed to discoloration during microwave treatments. Oil chemical constants of both husk and kernel oils treated by microwave heat were close to those treated by conventional heat. Further research is needed to investigate detailed oil characteristics and evaluate the feasibility study for using microwave energy, as a substitute for conventional heat in palm oil industry

  4. Effects of post-weld heat treatment on microstructure and mechanical properties of TLP bonded Inconel718 superalloy

    International Nuclear Information System (INIS)

    Cao, J.; Wang, Y.F.; Song, X.G.; Li, C.; Feng, J.C.

    2014-01-01

    Transient liquid phase bonding of Inconel718 superalloy was carried out using a commercial Ni–Cr–Si–B amorphous interlayer. The interfacial microstructure of Inconel718 joints was analyzed by a scanning electron microscope and a transmission electron microscope. In particular, the effects of post-weld heat treatment on the interfacial microstructure and joining properties of Inconel718 joints were investigated in detail. The results showed that the precipitation of second phases in joints induced by post-weld heat treatment were beneficial to the improvement of joint properties. A tensile strength of 1130 MPa with an elongation percentage of 7% was achieved for a sample bonded at 1050 °C/60 min+1180 °C/60 min followed by the post-weld heat treatment

  5. Effect of heat treatment of wood on the morphology, surface roughness and penetration of simulated and human blood.

    Science.gov (United States)

    Rekola, J; Lassila, L V J; Nganga, S; Ylä-Soininmäki, A; Fleming, G J P; Grenman, R; Aho, A J; Vallittu, P K

    2014-01-01

    Wood has been used as a model material for the development of novel fiber-reinforced composite bone substitute biomaterials. In previous studies heat treatment of wood was perceived to significantly increase the osteoconductivity of implanted wood material. The objective of this study was to examine some of the changing attributes of wood materials that may contribute to improved biological responses gained with heat treatment. Untreated and 140°C and 200°C heat-treated downy birch (Betula pubescens Ehrh.) were used as the wood materials. Surface roughness and the effect of pre-measurement grinding were measured with contact and non-contact profilometry. Liquid interaction was assessed with a dipping test using two manufactured liquids (simulated blood) as well as human blood. SEM was used to visualize possible heat treatment-induced changes in the hierarchical structure of wood. The surface roughness was observed to significantly decrease with heat treatment. Grinding methods had more influence on the surface contour and roughness than heat treatment. The penetration of the human blood in the 200°C heat-treated exceeded that in the untreated and 140°C heat-treated materials. SEM showed no significant change due to heat treatment in the dry-state morphology of the wood. The results of the liquid penetration test support previous findings in literature concerning the effects of heat treatment on the biological response to implanted wood. Heat-treatment has only a marginal effect on the surface contour of wood. The highly specialized liquid conveyance system of wood may serve as a biomimetic model for the further development of tailored fiber-composite materials.

  6. Nerve growth factor induces facial heat hyperalgesia and plays a role in trigeminal neuropathic pain in rats.

    Science.gov (United States)

    Dos Reis, Renata C; Kopruszinski, Caroline M; Nones, Carina F M; Chichorro, Juliana G

    2016-09-01

    There is preclinical evidence that nerve growth factor (NGF) contributes toward inflammatory hyperalgesia in the orofacial region, but the mechanisms underlying its hyperalgesic effect as well as its role in trigeminal neuropathic pain require further investigation. This study investigated the ability of NGF to induce facial heat hyperalgesia and the involvement of tyrosine kinase receptor A, transient receptor potential vanilloid 1, and mast cells in NGF pronociceptive effects. In addition, the role of NGF in heat hyperalgesia in a model of trigeminal neuropathic pain was evaluated. NGF injection into the upper lip of naive rats induced long-lasting heat hyperalgesia. Pretreatment with an antibody anti-NGF, antagonists of tyrosine kinase receptor A, and transient receptor potential vanilloid 1 receptors or compound 48/80, to induce mast-cell degranulation, all attenuated NGF-induced hyperalgesia. In a rat model of trigeminal neuropathic pain, local treatment with anti-NGF significantly reduced heat hyperalgesia. In addition, increased NGF levels were detected in the ipsilateral infraorbital nerve branch at the time point that represents the peak of heat hyperalgesia. The results suggest that NGF is a prominent hyperalgesic mediator in the trigeminal system and it may represent a potential therapeutic target for the management of painful orofacial conditions, including trigeminal neuropathic pain.

  7. Ploidy Manipulation of Zebrafish Embryos with Heat Shock 2 Treatment

    Science.gov (United States)

    Baars, Destiny L.; Pelegri, Francisco

    2016-01-01

    Manipulation of ploidy allows for useful transformations, such as diploids to tetraploids, or haploids to diploids. In the zebrafish Danio rerio, specifically the generation of homozygous gynogenetic diploids is useful in genetic analysis because it allows the direct production of homozygotes from a single heterozygous mother. This article describes a modified protocol for ploidy duplication based on a heat pulse during the first cell cycle, Heat Shock 2 (HS2). Through inhibition of centriole duplication, this method results in a precise cell division stall during the second cell cycle. The precise one-cycle division stall, coupled to unaffected DNA duplication, results in whole genome duplication. Protocols associated with this method include egg and sperm collection, UV treatment of sperm, in vitro fertilization and heat pulse to cause a one-cell cycle division delay and ploidy duplication. A modified version of this protocol could be applied to induce ploidy changes in other animal species. PMID:28060351

  8. 49 CFR 179.100-10 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.100-10 Section 179...-10 Postweld heat treatment. (a) After welding is complete, steel tanks and all attachments welded... treatment is prohibited. (c) Tank and welded attachments, fabricated from ASTM A 240/A 240M (IBR, see § 171...

  9. Sex specific effects of heat induced hormesis in Hsf-deficient Drosophila melanogaster

    DEFF Research Database (Denmark)

    Sørensen, J G; Kristensen, Torsten Nygård; Kristensen, K V

    2007-01-01

    In insects mild heat stress early in life has been reported to increase life span and heat resistance later in life, a phenomenon termed hormesis. Here, we test if the induction of the heat shock response by mild heat stress is mediating hormesis in longevity and heat resistance at older age...... line, seemingly mediated by the production of heat shock proteins (Hsps). The results indicate that heat inducible Hsps are important for heat induced hormesis in longevity and heat stress resistance. However, the results also suggest that other processes are involved and that different mechanisms...... might have marked sex specific impact...

  10. Heat shock protection against cold stress of Drosophila melanogaster

    OpenAIRE

    Burton, Vicky; Mitchell, Herschel K.; Young, Patricia; Petersen, Nancy S.

    1988-01-01

    Heat shock protein synthesis can be induced during recovery from cold treatment of Drosophila melanogaster larvae. Survival of larvae after a cold treatment is dramatically improved by a mild heat shock just before the cold shock. The conditions which induce tolerance to cold are similar to those which confer tolerance to heat.

  11. Effect of pre-cooling and heat treatment on antioxidant enzymes ...

    African Journals Online (AJOL)

    Effect of pre-cooling and heat treatment on antioxidant enzymes profile of mango and banana. ... In banana, pre-cooling treatment (8 ºC) and heat treatment followed by cooling reduced CAT activity in peel and pulp, whereas POX activity increased. Pre-cooling and heat treatments altered normal homeostasis of these fruits, ...

  12. Yeast cell inactivation related to local heating induced by low-intensity electric fields with long-duration pulses.

    Science.gov (United States)

    Guyot, Stéphane; Ferret, Eric; Boehm, Jean-Baptiste; Gervais, Patrick

    2007-01-25

    The effects of electric field (EF) treatments on Saccharomyces cerevisiae viability were investigated using a PG200 electroporator (Hoefer Scientific Instrument, San Fransisco, CA, USA) with specific attention to induced thermal effects on cell death. Lethal electric fields (1.5 kV cm(-1) for 5 s) were shown to cause heat variations in the cell suspension medium (water+glycerol), while corresponding classical thermal treatments at equivalent temperatures had no effect on the cells viability. Variations of the electrical conductivity of the intra- and extracellular matrix caused by ions and solutes transfer across the membrane were shown to be involved in the observed heating. The results permitted to build a theoretical model for the temperature variations induced by electric fields. Using this model and the electrical conductivity of the different media, a plausible explanation of the cell death induced by low-intensity electric fields with long-duration pulses has been proposed. Indeed, cell mortality could in part be caused by direct and indirect effects of electric fields. Direct effects are related to well known electromechanical phenomena, whereas indirect effects are related to secondary thermal stress caused by plasma membrane thermoporation. This thermoporation was attributed to electrical conductivity variations and the corresponding intracellular heating.

  13. Evaluation of focused ultrasound algorithms: Issues for reducing pre-focal heating and treatment time.

    Science.gov (United States)

    Yiannakou, Marinos; Trimikliniotis, Michael; Yiallouras, Christos; Damianou, Christakis

    2016-02-01

    Due to the heating in the pre-focal field the delay between successive movements in high intensity focused ultrasound (HIFU) are sometimes as long as 60s, resulting to treatment time in the order of 2-3h. Because there is generally a requirement to reduce treatment time, we were motivated to explore alternative transducer motion algorithms in order to reduce pre-focal heating and treatment time. A 1 MHz single element transducer with 4 cm diameter and 10 cm focal length was used. A simulation model was developed that estimates the temperature, thermal dose and lesion development in the pre-focal field. The simulated temperature history that was combined with the motion algorithms produced thermal maps in the pre-focal region. Polyacrylimde gel phantom was used to evaluate the induced pre-focal heating for each motion algorithm used, and also was used to assess the accuracy of the simulation model. Three out of the six algorithms having successive steps close to each other, exhibited severe heating in the pre-focal field. Minimal heating was produced with the algorithms having successive steps apart from each other (square, square spiral and random). The last three algorithms were improved further (with small cost in time), thus eliminating completely the pre-focal heating and reducing substantially the treatment time as compared to traditional algorithms. Out of the six algorithms, 3 were successful in eliminating the pre-focal heating completely. Because these 3 algorithms required no delay between successive movements (except in the last part of the motion), the treatment time was reduced by 93%. Therefore, it will be possible in the future, to achieve treatment time of focused ultrasound therapies shorter than 30 min. The rate of ablated volume achieved with one of the proposed algorithms was 71 cm(3)/h. The intention of this pilot study was to demonstrate that the navigation algorithms play the most important role in reducing pre-focal heating. By evaluating in

  14. Heat treatment control of Bi-2212 coils: I. Unravelling the complex dependence of the critical current density of Bi-2212 wires on heat treatment

    Science.gov (United States)

    Shen, Tengming; Li, Pei; Ye, Liyang

    2018-01-01

    A robust and reliable heat treatment is crucial for developing superconducting magnets from several superconductors especially Bi-2212. An improper heat treatment may significantly reduce the critical current density Jc of a Bi-2212 superconducting coil, even to zero, since the Jc of Bi-2212 wires is sensitive to parameters of its heat treatment (partial melt processing). To provide an essential database for heat treating Bi-2212 coils, the dependence of Jc on heat treatment is studied systematically in 11 industrial Bi-2212 wires, revealing several common traits shared between these wires and outlier behaviors. The dependence of the Jc of Bi-2212 on heat treatment is rather complex, with many processing parameters affecting Jc, including the peak processing temperature Tp, the time at the peak temperature tp, the time in the melt tmelt, the rate at which Bi-2212 melt is initially cooled CR1, the rate at which the solidification of Bi-2212 melt occurs CR2, and the temperature Tq at which the cooling rate switches from CR1 to CR2. The role of these parameters is analyzed and clarified, in the perspective of heat treating a coil. Practical advices on heat treatment design are given. The ability of a Bi-2212 coil to follow the prescribed recipe decreases with increasing coil sizes. The size of a coil that can be properly heat treated is determined.

  15. Effect of heat treatment at 600 degree C for 10 hours on human BMP

    International Nuclear Information System (INIS)

    Izawa, H.; Hachiya, Y.; Muramatsu, K.; Narita, Y.; Kawai, T.

    1999-01-01

    Viral infection are an extremely serious in allogeneic bone transplantations. While it is essential to kill viruses such as HIV in allogeneic bone graft, the osteoinductive activity must be preserved. Heat treatment of allogeneic bone graft at 60 degree C for 10 hours is effective in killing viruses such as HIV, but it is unclear to what extent the activity of human bone morphogenetic protein (hBMP) is preserved. In this experiment crude hBMP was extracted from both heated and non-heated human bones which were decalcified by the Urist method. Gelatin capsules containing 5mg of crude hBMP were transplanted into the thigh muscles of 5 week old mice. Human bone samples heated in a water bath at 60 degree C for 10 hours and non-heated samples were each transplanted into 5 mice. At 20 days after transplantation, the heterotopic bone formation was compared by evaluation of X-ray and histologicic analysis. X-rays showed heterotopic bone formation in both heated and non-heated samples. Further, histologic analysis showed that peripheral osteoid tissue had developed into laminar bone formation and interlaminar bone marrow was observed. Heterotopic bone formation was induced by crude hBMP from heated bones in a similar way to crude hBMP from non-heated bones observed in X-ray. There was no significant difference in histologic analysis. The crude hBMP, extracted from bones which were heat-treated at 60 degree C for 10 hours induced heterotopic bone formation similar to that in non-heated bone observed by X-ray and histologic analysis at 20 days after transplantation. This demostrates that the heat-treated bone preserved osteoinduction

  16. Lowcost automated control for steel heat treatments

    International Nuclear Information System (INIS)

    Zambaldi, Edimilson; Magalhães, Ricardo R.; Barbosa, Bruno H.G.; Silva, Sandro P. da; Ferreira, Danton D.

    2017-01-01

    Highlights: • Control the furnace temperature measured by thermocouple and adjusts it. • Activating the furnace resistors through Pulse Width Modulation. • Appling heat treatments to steels by a low-cost controller. - Abstract: The aim of this paper is to propose a low cost, automated furnace control system for the heat treatment of steel. We used an open source electronic prototyping platform to control the furnace temperature, thus reducing human interaction during the heat process. The platform can be adapted to non-controlled commercial furnaces, which are often used by small businesses. A Proportional-Integral-Derivative (PID) controller was implemented to regulate the furnace temperature based on a defined heat treatment cycle. The embedded system activates the furnace resistors through Pulse Width Modulation (PWM), allowing for control of electrical power supplied to the furnace. Hardening and tempering were performed on standard steel samples using a traditional method (visual inspection without temperature control) as well the embedded system with PID feedback control. The results show that the proposed system can reproduce an arbitrary heat treatment curve with accuracy and provide the desired final hardness as inferred through metallographic analysis. In addition, we observed a 6% saving in energy consumption using the proposed control system. Furthermore, the estimated cost to implement the system is 42% lower than a commercial controller model implemented in commercial furnaces.

  17. Mortality of insect life stages during simulated heat treatment

    Science.gov (United States)

    . Heat treatment for insect disinfestation uses elevated air temperatures that are lethal to stored-product insects. Heat treatment has been demonstrated in our research to offer a reduced-risk alternative to fumigation or residual pesticide use in empty bins. Heat is also compatible with organic gr...

  18. Induced current heating probe

    International Nuclear Information System (INIS)

    Thatcher, G.; Ferguson, B.G.; Winstanley, J.P.

    1984-01-01

    An induced current heating probe is of thimble form and has an outer conducting sheath and a water flooded flux-generating unit formed from a stack of ferrite rings coaxially disposed in the sheath. The energising coil is made of solid wire which connects at one end with a coaxial water current tube and at the other end with the sheath. The stack of ferrite rings may include non-magnetic insulating rings which help to shape the flux. (author)

  19. Plasma treatment of heat-resistant materials

    International Nuclear Information System (INIS)

    Vlasov, V A; Kosmachev, P V; Skripnikova, N K; Bezukhov, K A

    2015-01-01

    Refractory lining of thermal generating units is exposed to chemical, thermal, and mechanical attacks. The degree of fracture of heat-resistant materials depends on the chemical medium composition, the process temperature and the material porosity. As is known, a shortterm exposure of the surface to low-temperature plasma (LTP) makes possible to create specific coatings that can improve the properties of workpieces. The aim of this work is to produce the protective coating on heat-resistant chamotte products using the LTP technique. Experiments have shown that plasma treatment of chamotte products modifies the surface, and a glass-ceramic coating enriched in mullite is formed providing the improvement of heat resistance. For increasing heat resistance of chamotte refractories, pastes comprising mixtures of Bacor, alumina oxide, and chamot were applied to their surfaces in different ratios. It is proved that the appropriate coating cannot be created if only one of heat-resistant components is used. The required coatings that can be used and recommended for practical applications are obtained only with the introduction of powder chamot. The paste composition of 50% chamot, 25% Bacor, and 25% alumina oxide exposed to plasma treatment, has demonstrated the most uniform surface fusion. (paper)

  20. Heat Treatment of Tools in Light Industry

    Science.gov (United States)

    Petukhov, V. A.

    2005-09-01

    Heat treatment processes for some tools (knitting needles, travelers for thimbles of spinning and doubling frames, thread-forming spinnerets) used for the production of cloths, hosiery, and other articles) in the knitting and textile industries are considered. Problems of the choice of steel and the kind and parameters of heat treatment are discussed in connection with the special features of tool design and operating conditions.

  1. 49 CFR 179.300-10 - Postweld heat treatment.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Postweld heat treatment. 179.300-10 Section 179.300-10 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Postweld heat treatment. After welding is complete, steel tanks and all attachments welded thereto, must be...

  2. 7 CFR 58.236 - Pasteurization and heat treatment.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Pasteurization and heat treatment. 58.236 Section 58... Service 1 Operations and Operating Procedures § 58.236 Pasteurization and heat treatment. All milk and... is handled according to sanitary conditions approved by the Administrator. (a) Pasteurization. (1...

  3. Dry Heat Treatment Reduces the Occurrence of Cladosporium cucumerinum, Ascochyta citrullina, and Colletotrichum orbiculare on the Surface and Interior of Cucumber Seeds

    Directory of Open Access Journals (Sweden)

    Yanxia Shi

    2016-01-01

    Full Text Available Dry heat treatment has been identified as a method for disinfecting seed-borne pathogens in vegetable seeds. This study demonstrated that three seed-borne pathogens of cucumber (Cladosporium cucumerinum that causes scabs, Ascochyta citrullina that results in gummy stem blight, and Colletotrichum orbiculare that induces anthracnose could be effectively eradicated from cucumber seeds by dry heat treatment. In vitro growth of these three pathogens was inhibited by dry heat treatment at 70 °C for 40 min. These pathogens were inactivated after exposing infected seeds to 70 °C dry heat for at least 90 min. Seed infection was significantly reduced by exposing the seeds to 70 °C dry heat for at least 40 min. Seed moisture content and germination were slightly reduced after 70 °C heat treatment for 40–120 min. Seed vigor remained at a high level after dry heat treatment at 70 °C for 90 min. In conclusion, 70 °C dry heat treatment for 90 min was determined to be the optimal method for eradication of C. cucumerinum, Didymella bryoniae, and C. orbiculare from cucumber seeds.

  4. Metabolite responses to exogenous application of nitrogen, cytokinin, and ethylene inhibitors in relation to heat-induced senescence in creeping bentgrass.

    Directory of Open Access Journals (Sweden)

    David Jespersen

    Full Text Available The exogenous application of ethylene inhibitors, cytokinins, or nitrogen has previously been shown to suppress heat-induced senescence and improve heat tolerance in cool-season grasses. The objectives of this study were to examine metabolic profiles altered by exogenous treatment of creeping bentgrass with an ethylene inhibitor, cytokinin or nitrogen under heat stress and to determine metabolic pathways regulated by those compounds in association with their effectiveness for improving heat tolerance. Creeping bentgrass (Agostis stolonifera plants (cv. Penncross were foliar sprayed with 18 mM carbonyldiamide (N source, 25 μM aminoethoxyvinylglycine (AVG, ethylene inhibitor, 25 μM zeatin riboside (ZR, cytokinin, or a water control, and then exposed to 20/15°C (day/night or 35/30°C (heat stress in growth chambers. All three exogenous treatments suppressed leaf senescence, as manifested by increased turf quality and chlorophyll content, and reduced electrolyte leakage under heat stress. Polar metabolite profiling identified increases in the content of certain organic acids (i.e. citric and malic acid, sugar alcohols, disaccharides (sucrose, and decreased accumulations of monosaccharides (i.e. glucose and fructose with exogenous treatment of N, AVG, or ZR at the previously mentioned concentrations when compared to the untreated control under heat stress. Nitrogen stimulated amino acid accumulation whereas AVG and ZR reduced amino acid accumulation compared to the untreated control under heat stress. These results revealed that the alleviation of heat-induced leaf senescence by N, AVG, and ZR could be due to changes in the accumulation of metabolites involved in osmoregulation, antioxidant metabolism, carbon and nitrogen metabolism, as well as stress signaling molecules.

  5. Comparative proteomic and metabolomic profiling of citrus fruit with enhancement of disease resistance by postharvest heat treatment.

    Science.gov (United States)

    Yun, Ze; Gao, Huijun; Liu, Ping; Liu, Shuzhen; Luo, Tao; Jin, Shuai; Xu, Qiang; Xu, Juan; Cheng, Yunjiang; Deng, Xiuxin

    2013-03-16

    From field harvest to the consumer's table, fresh citrus fruit spends a considerable amount of time in shipment and storage. During these processes, physiological disorders and pathological diseases are the main causes of fruit loss. Heat treatment (HT) has been widely used to maintain fruit quality during postharvest storage; however, limited molecular information related to this treatment is currently available at a systemic biological level. Mature 'Kamei' Satsuma mandarin (Citrus unshiu Marc.) fruits were selected for exploring the disease resistance mechanisms induced by HT during postharvest storage. Proteomic analyses based on two-dimensional gel electrophoresis (2-DE), and metabolomic research based on gas chromatography coupled to mass spectrometry (GC-MS), and liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS) were conducted. The results show resistance associated proteins were up-regulated in heat treated pericarp, such as beta-1, 3-glucanase, Class III chitinase, 17.7 kDa heat shock protein and low molecular weight heat-shock protein. Also, redox metabolism enzymes were down-regulated in heat treated pericarp, including isoflavone reductase, oxidoreductase and superoxide dismutase. Primary metabolic profiling revealed organic acids and amino acids were down-regulated in heat treated pericarp; but significant accumulation of metabolites, including tetradecanoic acid, oleic acid, ornithine, 2-keto-d-gluconic acid, succinic acid, turanose, sucrose, galactose, myo-inositol, glucose and fructose were detected. Noticeably, H2O2 content decreased, while, lignin content increased in heat treated pericarp compared to the control, which might increase fruit resistibility in response to external stress. Also, flavonoids, substances which are well-known to be effective in reducing external stress, were up-regulated in heat treated pericarp. This study provides a broad picture of differential accumulation of proteins and metabolites in

  6. Failures of tool steels after heat treatments

    International Nuclear Information System (INIS)

    Nunez-Gonzalez, G.

    1990-01-01

    The main objective of the work was to determine the most common defects occuring in tool steels of the AISI D-2, S-1, 0-1 and W-2 series during thermal treatment. Defects were evaluated by metallographic analyses, a method used to determine and recognize micro structural defects and their origin in order to be able to eliminate and correct some of the stages that are caused by heat treatment. Results show a large number of defects due to irregularities during thermal heating such as excess or lack of temperature, heating time, and atmosphere, rectifying and handling in service and, to a lesser extent, poor design. In conclusion, with the results obtained for each of the thermal treatments it is necessary to define, particularly the values each of these variables should have since they affect the material properties. (Author)

  7. Integration of Heat Treatment with Shot Peening of 17-4 Stainless Steel Fabricated by Direct Metal Laser Sintering

    Science.gov (United States)

    AlMangour, Bandar; Yang, Jenn-Ming

    2017-11-01

    Direct metal laser sintering (DMLS) is a promising powder-based additive manufacturing process for fabrication of near-net-shape parts. However, the typically poor fatigue performance of DMLS parts must be addressed for use in demanding industrial applications. Post-treatment can be applied to enhance the performance of such components. Earlier attempts at inducing grain refinement through severe plastic deformation of part surfaces using shot peening improved the physical and mechanical properties of metals without chemical alteration. However, heat treatment can modify the surface-hardening effects attained by shot peening. Hence, we examined the feasibility of applying shot peening combined with heat treatment to improve the performance of DMLS-fabricated 17-4 stainless steel parts through microstructural evolution studies and hardness measurements. Compared to a specimen treated only by shot peening, the sample exposed to additional heat treatment showed increased hardness due to aging of the dominant phase.

  8. Using geothermal energy to heat a portion of a formation for an in situ heat treatment process

    Science.gov (United States)

    Pieterson, Roelof; Boyles, Joseph Michael; Diebold, Peter Ulrich

    2010-06-08

    Methods of using geothermal energy to treat subsurface formations are described herein. Methods for using geothermal energy to treat a subsurface treatment area containing or proximate to hydrocarbons may include producing geothermally heated fluid from at least one subsurface region. Heat from at least a portion of the geothermally heated fluid may be transferred to the subsurface treatment area to heat the subsurface treatment area. At least some hydrocarbon fluids may be produced from the formation.

  9. Heat-modified citrus pectin induces apoptosis-like cell death and autophagy in HepG2 and A549 cancer cells.

    Science.gov (United States)

    Leclere, Lionel; Fransolet, Maude; Cote, Francois; Cambier, Pierre; Arnould, Thierry; Van Cutsem, Pierre; Michiels, Carine

    2015-01-01

    Cancer is still one of the leading causes of death worldwide, and finding new treatments remains a major challenge. Previous studies showed that modified forms of pectin, a complex polysaccharide present in the primary plant cell wall, possess anticancer properties. Nevertheless, the mechanism of action of modified pectin and the pathways involved are unclear. Here, we show that citrus pectin modified by heat treatment induced cell death in HepG2 and A549 cells. The induced cell death differs from classical apoptosis because no DNA cleavage was observed. In addition, Z-VAD-fmk, a pan-caspase inhibitor, did not influence the observed cell death in HepG2 cells but appeared to be partly protective in A549 cells, indicating that heat-modified citrus pectin might induce caspase-independent cell death. An increase in the abundance of the phosphatidylethanolamine-conjugated Light Chain 3 (LC3) protein and a decrease in p62 protein abundance were observed in both cell types when incubated in the presence of heat-modified citrus pectin. These results indicate the activation of autophagy. To our knowledge, this is the first time that autophagy has been revealed in cells incubated in the presence of a modified form of pectin. This autophagy activation appears to be protective, at least for A549 cells, because its inhibition with 3-methyladenine increased the observed modified pectin-induced cytotoxicity. This study confirms the potential of modified pectin to improve chemotherapeutic cancer treatments.

  10. Heat-modified citrus pectin induces apoptosis-like cell death and autophagy in HepG2 and A549 cancer cells.

    Directory of Open Access Journals (Sweden)

    Lionel Leclere

    Full Text Available Cancer is still one of the leading causes of death worldwide, and finding new treatments remains a major challenge. Previous studies showed that modified forms of pectin, a complex polysaccharide present in the primary plant cell wall, possess anticancer properties. Nevertheless, the mechanism of action of modified pectin and the pathways involved are unclear. Here, we show that citrus pectin modified by heat treatment induced cell death in HepG2 and A549 cells. The induced cell death differs from classical apoptosis because no DNA cleavage was observed. In addition, Z-VAD-fmk, a pan-caspase inhibitor, did not influence the observed cell death in HepG2 cells but appeared to be partly protective in A549 cells, indicating that heat-modified citrus pectin might induce caspase-independent cell death. An increase in the abundance of the phosphatidylethanolamine-conjugated Light Chain 3 (LC3 protein and a decrease in p62 protein abundance were observed in both cell types when incubated in the presence of heat-modified citrus pectin. These results indicate the activation of autophagy. To our knowledge, this is the first time that autophagy has been revealed in cells incubated in the presence of a modified form of pectin. This autophagy activation appears to be protective, at least for A549 cells, because its inhibition with 3-methyladenine increased the observed modified pectin-induced cytotoxicity. This study confirms the potential of modified pectin to improve chemotherapeutic cancer treatments.

  11. Examination of heat treatments at preservation of grape must

    Directory of Open Access Journals (Sweden)

    Péter Korzenszky

    2014-02-01

    Full Text Available Heat treatment is a well-known process in food preservation. It is made to avoid and to slow down food deterioration. The process was developed by Louise Pasteur French scientist to avoid late among others wine further fermentation. The different heat treatments influence the shelf life in food production. In our article we present the process of grape must fermentation, as grape must is the base material of wine production. The treatment of harvested fresh grape juice has a big influence on end product quality. It is our experiments we examined the same grape must with four different methods in closed and in open spaces to determine CO2 concentration change. There are four different methods for treatment of grape juice: boiling, microwave treatment, treatment by water bath thermostat and a control without treatment. As a result of the comparison it can be stated that the heat treatment delays the start of fermentation, thereby increasing shelf life of grape must. However, no significant differences were found between two fermentation of heat-treated grape must by the microwave and water-bath thermostat. The different heat treatment of grape must base materials was done at the laboratory in Faculty of Mechanical Engineering of Szent István University. The origin of the table grapes used for the examination was Gödöllő-hillside. Normal 0 21 false false false HU X-NONE X-NONE

  12. Diffusion induced by cyclotron resonance heating

    International Nuclear Information System (INIS)

    Riyopoulos, S.; Tajima, T.; Hatori, T.; Pfirsch, D.

    1985-09-01

    The wave induced particle transport during the ion cyclotron resonance heating is studied in collisionless toroidal plasmas. It is shown that the previously neglected non-conservation of the toroidal angular momentum IP/sub phi/ caused by the toroidal wave component E/sub phi/ is necessary to allow particle diffusion and yields the leading diffusive contribution. While the induced ion transport for the rf power in contemporary experiments is of the order of the neoclassical value, that of fast alpha particles is quite large if resonance is present

  13. Heat treatment, microstructure and mechanical properties of a C–Mn–Al–P hot dip galvanizing TRIP steel

    International Nuclear Information System (INIS)

    Ding, Wei; Hedström, Peter; Li, Yan

    2016-01-01

    Heat treatments of a hot dip galvanizing TRIP (Transformation induced plasticity) steel with chemical composition 0.20C-1.50Mn-1.2Al-0.07P(mass%) were performed in a Gleeble 3500 laboratory equipment. The heat treatment process parameters were varied to investigate the effect of intercritical annealing temperature as well as isothermal bainitic transformation (IBT) temperature and time, on the microstructure and the mechanical properties. The microstructure was investigated using scanning electron microscopy, transmission electron microscopy and x-ray diffraction, while mechanical properties were evaluated by tensile testing. Furthermore, to generate a better understanding of the phase transformations during heat treatment, dilatometry trials were conducted. The desired microstructure containing ferrite, bainite, retained austenite and martensite was obtained after the heat treatments. It was further found that the IBT is critical in determining the mechanical properties of the steel, since it controls the fraction of bainite. With increasing bainite fraction, the fraction of retained austenite increases while the fraction of martensite decreases. The mechanical properties of the steel are excellent with a tensile strength above 780 MPa (expect in one case) and elongation above 22%.

  14. Heat treatment, microstructure and mechanical properties of a C–Mn–Al–P hot dip galvanizing TRIP steel

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Wei [School of Material and Metallurgy, Inner Mongolia University of Science and Technology, Baotou 014010 (China); Department of Materials Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Bayan Obo multimetallic resource comprehensive utilization Key lab, Inner Mongolia University of Science and Technology, Baotou 014010 (China); Hedström, Peter [Department of Materials Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Li, Yan [Department of Materials Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Bayan Obo multimetallic resource comprehensive utilization Key lab, Inner Mongolia University of Science and Technology, Baotou 014010 (China)

    2016-09-30

    Heat treatments of a hot dip galvanizing TRIP (Transformation induced plasticity) steel with chemical composition 0.20C-1.50Mn-1.2Al-0.07P(mass%) were performed in a Gleeble 3500 laboratory equipment. The heat treatment process parameters were varied to investigate the effect of intercritical annealing temperature as well as isothermal bainitic transformation (IBT) temperature and time, on the microstructure and the mechanical properties. The microstructure was investigated using scanning electron microscopy, transmission electron microscopy and x-ray diffraction, while mechanical properties were evaluated by tensile testing. Furthermore, to generate a better understanding of the phase transformations during heat treatment, dilatometry trials were conducted. The desired microstructure containing ferrite, bainite, retained austenite and martensite was obtained after the heat treatments. It was further found that the IBT is critical in determining the mechanical properties of the steel, since it controls the fraction of bainite. With increasing bainite fraction, the fraction of retained austenite increases while the fraction of martensite decreases. The mechanical properties of the steel are excellent with a tensile strength above 780 MPa (expect in one case) and elongation above 22%.

  15. Biophoton emission induced by heat shock.

    Directory of Open Access Journals (Sweden)

    Katsuhiro Kobayashi

    Full Text Available Ultraweak biophoton emission originates from the generation of reactive oxygen species (ROS that are produced in mitochondria as by-products of cellular respiration. In healthy cells, the concentration of ROS is minimized by a system of biological antioxidants. However, heat shock changes the equilibrium between oxidative stress and antioxidant activity, that is, a rapid rise in temperature induces biophoton emission from ROS. Although the rate and intensity of biophoton emission was observed to increase in response to elevated temperatures, pretreatment at lower high temperatures inhibited photon emission at higher temperatures. Biophoton measurements are useful for observing and evaluating heat shock.

  16. Effect of heat treatment on carbon steel pipe welds

    International Nuclear Information System (INIS)

    Mohamad Harun.

    1987-01-01

    The heat treatment to improve the altered properties of carbon steel pipe welds is described. Pipe critical components in oil, gasification and nuclear reactor plants require adequate room temperature toughness and high strength at both room and moderately elevated temperatures. Microstructure and microhardness across the welds were changed markedly by the welding process and heat treatment. The presentation of hardness fluctuation in the welds can produce premature failure. A number of heat treatments are suggested to improve the properties of the welds. (author) 8 figs., 5 refs

  17. Mechanical analysis of a heat-shock induced developmental defect

    Science.gov (United States)

    Crews, Sarah M.; McCleery, W. Tyler; Hutson, M. Shane

    2014-03-01

    Embryonic development in Drosophila is a complex process involving coordinated movements of mechanically interacting tissues. Perturbing this system with a transient heat shock can result in a number of developmental defects. In particular, a heat shock applied during the earliest morphogenetic movements of gastrulation can lead to apparent recovery, but then subsequent morphogenetic failure 5-6 hours later during germ band retraction. The process of germ band retraction requires an intact amnioserosa - a single layered extra-embryonic epithelial tissue - and heat shock at gastrulation can induce the later opening of holes in the amnioserosa. These holes are highly correlated with failures of germ band retraction. These holes could be caused by a combination of mechanical weakness in the amnioserosa or local increases in mechanical stress. Here, we assess the role of mechanical stress using confocal imaging to compare cell and tissue morphology in the amnioserosa of normal and heat-shocked embryos and laser hole drilling to map the stress field around the times and locations at which heat-shock induced holes open.

  18. Heat Treatment and Properties of Iron and Steel

    National Research Council Canada - National Science Library

    Digges, Thomas

    1966-01-01

    .... Chemical compositions, heat treatments, and some properties and uses are presented for structural steels, tool steels, stainless and heat-resisting steels, precipitation-hardenable stainless steels...

  19. Exercise-induced heat stress disrupts the shear-dilatory relationship.

    Science.gov (United States)

    Ives, Stephen J; Lefferts, Wesley K; Wharton, Margret; Fehling, Patricia C; Smith, Denise L

    2016-12-01

    What is the central question of this study? Although heat stress is known to increase cardiovascular strain, no study, to date, had explored the potential impact of exercise-induced heat stress on vascular function. What is the main finding and its importance? We found that acute exercise tended to reduce flow-mediated dilatation (FMD), owing in part to reduced reactive hyperaemia/shear stimulus; thus, when FMD is normalized to shear no postexercise deficit exists. Exercise-induced heat stress increased reactive hyperaemia, shear rate, coupled with a sustained FMD postexercise, suggests that exercise-induced heat stress increases the amount of shear stimulus to elicit a similar response, indicating reduced vascular responsiveness, or reserve, which might increase cardiovascular susceptibility. Heat stress increases cardiovascular strain and is of particular concern in occupations, such as firefighting, in which individuals are required to perform strenuous work while wearing personal protective equipment. Sudden cardiac events are associated with strenuous activity and are the leading cause of duty-related death among firefighters, accounting for ∼50% of duty-related fatalities per year. Understanding the acute effects of exercise-induced heat stress (EIHS) on vascular endothelial function may provide insight into the mechanisms precipitating acute coronary events in firefighters. The purpose of this study, therefore, was to determine the effects of EIHS on vascular endothelial function. Using a balanced crossover design, 12 healthy men performed 100 min of moderate-intensity, intermittent exercise with and without EIHS (personal protective equipment or cooling vest, respectively). Measurements of flow-mediated dilatation (FMD), reactive hyperaemia and shear rate area under the curve (SR AUC ) were performed pre- and postexercise. During EIHS, core temperature was significantly higher (38 ± 0.1 versus 37 ± 0.1°C). Postexercise FMD tended to be suppressed

  20. An improved model of heat-induced hyperalgesia--repetitive phasic heat pain causing primary hyperalgesia to heat and secondary hyperalgesia to pinprick and light touch.

    Science.gov (United States)

    Jürgens, Tim P; Sawatzki, Alexander; Henrich, Florian; Magerl, Walter; May, Arne

    2014-01-01

    This study tested a modified experimental model of heat-induced hyperalgesia, which improves the efficacy to induce primary and secondary hyperalgesia and the efficacy-to-safety ratio reducing the risk of tissue damage seen in other heat pain models. Quantitative sensory testing was done in eighteen healthy volunteers before and after repetitive heat pain stimuli (60 stimuli of 48°C for 6 s) to assess the impact of repetitive heat on somatosensory function in conditioned skin (primary hyperalgesia area) and in adjacent skin (secondary hyperalgesia area) as compared to an unconditioned mirror image control site. Additionally, areas of flare and secondary hyperalgesia were mapped, and time course of hyperalgesia determined. After repetitive heat pain conditioning we found significant primary hyperalgesia to heat, and primary and secondary hyperalgesia to pinprick and to light touch (dynamic mechanical allodynia). Acetaminophen (800 mg) reduced pain to heat or pinpricks only marginally by 11% and 8%, respectively (n.s.), and had no effect on heat hyperalgesia. In contrast, the areas of flare (-31%) and in particular of secondary hyperalgesia (-59%) as well as the magnitude of hyperalgesia (-59%) were significantly reduced (all pheat pain induces significant peripheral sensitization (primary hyperalgesia to heat) and central sensitization (punctate hyperalgesia and dynamic mechanical allodynia). These findings are relevant to further studies using this model of experimental heat pain as it combines pronounced peripheral and central sensitization, which makes a convenient model for combined pharmacological testing of analgesia and anti-hyperalgesia mechanisms related to thermal and mechanical input.

  1. An Improved Model of Heat-Induced Hyperalgesia—Repetitive Phasic Heat Pain Causing Primary Hyperalgesia to Heat and Secondary Hyperalgesia to Pinprick and Light Touch

    Science.gov (United States)

    Henrich, Florian; Magerl, Walter; May, Arne

    2014-01-01

    This study tested a modified experimental model of heat-induced hyperalgesia, which improves the efficacy to induce primary and secondary hyperalgesia and the efficacy-to-safety ratio reducing the risk of tissue damage seen in other heat pain models. Quantitative sensory testing was done in eighteen healthy volunteers before and after repetitive heat pain stimuli (60 stimuli of 48°C for 6 s) to assess the impact of repetitive heat on somatosensory function in conditioned skin (primary hyperalgesia area) and in adjacent skin (secondary hyperalgesia area) as compared to an unconditioned mirror image control site. Additionally, areas of flare and secondary hyperalgesia were mapped, and time course of hyperalgesia determined. After repetitive heat pain conditioning we found significant primary hyperalgesia to heat, and primary and secondary hyperalgesia to pinprick and to light touch (dynamic mechanical allodynia). Acetaminophen (800 mg) reduced pain to heat or pinpricks only marginally by 11% and 8%, respectively (n.s.), and had no effect on heat hyperalgesia. In contrast, the areas of flare (−31%) and in particular of secondary hyperalgesia (−59%) as well as the magnitude of hyperalgesia (−59%) were significantly reduced (all pheat pain induces significant peripheral sensitization (primary hyperalgesia to heat) and central sensitization (punctate hyperalgesia and dynamic mechanical allodynia). These findings are relevant to further studies using this model of experimental heat pain as it combines pronounced peripheral and central sensitization, which makes a convenient model for combined pharmacological testing of analgesia and anti-hyperalgesia mechanisms related to thermal and mechanical input. PMID:24911787

  2. Thermoluminescent determination of prehistoric heat treatment of chert artifacts

    International Nuclear Information System (INIS)

    Melcher, C.L.; Zimmerman, D.W.

    1977-01-01

    In recent years archeologists have become interested in the extent to which prehistoric peoples heat-treated chert prior to shaping it into tools. Thermoluminescent determination of the radiation dose accumulated by an artifact since it was formed or last heated provides a simple, reliable test for such heat treatment. This test can be applied to single artifacts without the need for raw source material for comparison. Results on 25 artifacts from four sites indicate that, for many chert sources, color and luster are not useful indicators of heat treatment by prehistoric peoples

  3. Investigation of anodic oxide coatings on zirconium after heat treatment

    International Nuclear Information System (INIS)

    Sowa, Maciej; Dercz, Grzegorz; Suchanek, Katarzyna; Simka, Wojciech

    2015-01-01

    Highlights: • Oxide layers prepared via PEO of zirconium were subjected to heat treatment. • Surface characteristics were determined for the obtained oxide coatings. • Heat treatment led to the partial destruction of the anodic oxide layer. • Pitting corrosion resistance of zirconium was improved after the modification. - Abstract: Herein, results of heat treatment of zirconium anodised under plasma electrolytic oxidation (PEO) conditions at 500–800 °C are presented. The obtained oxide films were investigated by means of SEM, XRD and Raman spectroscopy. The corrosion resistance of the zirconium specimens was evaluated in Ringer's solution. A bilayer oxide coatings generated in the course of PEO of zirconium were not observed after the heat treatment. The resulting oxide layers contained a new sublayer located at the metal/oxide interface is suggested to originate from the thermal oxidation of zirconium. The corrosion resistance of the anodised metal was improved after the heat treatment

  4. Renoprotective effect of virgin coconut oil in heated palm oil diet-induced hypertensive rats.

    Science.gov (United States)

    Kamisah, Yusof; Ang, Shu-Min; Othman, Faizah; Nurul-Iman, Badlishah Sham; Qodriyah, Hj Mohd Saad

    2016-10-01

    Virgin coconut oil, rich in antioxidants, was shown to attenuate hypertension. This study aimed to investigate the effects of virgin coconut oil on blood pressure and related parameters in kidneys in rats fed with 5-times-heated palm oil (5HPO). Thirty-two male Sprague-Dawley rats were divided into 4 groups. Two groups were fed 5HPO (15%) diet and the second group was also given virgin coconut oil (1.42 mL/kg, oral) daily for 16 weeks. The other 2 groups were given basal diet without (control) and with virgin coconut oil. Systolic blood pressure was measured pre- and post-treatment. After 16 weeks, the rats were sacrificed and kidneys were harvested. Dietary 5HPO increased blood pressure, renal thiobarbituric acid reactive substance (TBARS), and nitric oxide contents, but decreased heme oxygenase activity. Virgin coconut oil prevented increase in 5HPO-induced blood pressure and renal nitric oxide content as well as the decrease in renal heme oxygenase activity. The virgin coconut oil also reduced the elevation of renal TBARS induced by the heated oil. However, neither dietary 5HPO nor virgin coconut oil affected renal histomorphometry. In conclusion, virgin coconut oil has a potential to reduce the development of hypertension and renal injury induced by dietary heated oil, possibly via its antioxidant protective effects on the kidneys.

  5. Physical aspects of thermotherapy: A study of heat transport with a view to treatment optimisation

    Science.gov (United States)

    Olsrud, Johan Karl Otto

    1998-12-01

    Local treatment with the aim to destruct tissue by heating (thermotherapy) may in some cases be an alternative or complement to surgical methods, and has gained increased interest during the last decade. The major advantage of these, often minimally-invasive methods, is that the disease can be controlled with reduced treatment trauma and complications. The extent of thermal damage is a complex function of the physical properties of tissue, which influence the temperature distribution, and of the biological response to heat. In this thesis, methods of obtaining a well-controlled treatment have been studied from a physical point of view, with emphasis on interstitial laser-induced heating of tumours in the liver and intracavitary heating as a treatment for menorrhagia. Hepatic inflow occlusion, in combination with temperature-feedback control of the output power of the laser, resulted in well defined damaged volumes during interstitial laser thermotherapy in normal porcine liver. In addition, phantom experiments showed that the use of multiple diffusing laser fibres allows heating of clinically relevant tissue volumes in a single session. Methods for numerical simulation of heat transport were used to calculate the temperature distribution and the results agreed well with experiments. It was also found from numerical simulation that the influence of light transport on the damaged volume may be negligible in interstitial laser thermotherapy in human liver. Finite element analysis, disregarding light transport, was therefore proposed as a suitable method for 3D treatment planning. Finite element simulation was also used to model intracavitary heating of the uterus, with the purpose of providing an increased understanding of the influence of various treatment parameters on blood flow and on the depth of tissue damage. The thermal conductivity of human uterine tissue, which was used in these simulations, was measured. Furthermore, magnetic resonance imaging (MRI) was

  6. Cellular stress induces cancer stem-like cells through expression of DNAJB8 by activation of heat shock factor 1.

    Science.gov (United States)

    Kusumoto, Hiroki; Hirohashi, Yoshihiko; Nishizawa, Satoshi; Yamashita, Masamichi; Yasuda, Kazuyo; Murai, Aiko; Takaya, Akari; Mori, Takashi; Kubo, Terufumi; Nakatsugawa, Munehide; Kanaseki, Takayuki; Tsukahara, Tomohide; Kondo, Toru; Sato, Noriyuki; Hara, Isao; Torigoe, Toshihiko

    2018-03-01

    In a previous study, we found that DNAJB8, a heat shock protein (HSP) 40 family member is expressed in kidney cancer stem-like cells (CSC)/cancer-initiating cells (CIC) and that it has a role in the maintenance of kidney CSC/CIC. Heat shock factor (HSF) 1 is a key transcription factor for responses to stress including heat shock, and it induces HSP family expression through activation by phosphorylation. In the present study, we therefore examined whether heat shock (HS) induces CSC/CIC. We treated the human kidney cancer cell line ACHN with HS, and found that HS increased side population (SP) cells. Western blot analysis and qRT-PCR showed that HS increased the expression of DNAJB8 and SOX2. Gene knockdown experiments using siRNAs showed that the increase in SOX2 expression and SP cell ratio depends on DNAJB8 and that the increase in DNAJB8 and SOX2 depend on HSF1. Furthermore, treatment with a mammalian target of rapamycin (mTOR) inhibitor, temsirolimus, decreased the expression of DNAJB8 and SOX2 and the ratio of SP cells. Taken together, the results indicate that heat shock induces DNAJB8 by activation of HSF1 and induces cancer stem-like cells. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  7. Efficacy of heat treatment for disinfestation of concrete grain silos

    Science.gov (United States)

    Field experiments were conducted in 2007 and 2008 to evaluate heat treatment for disinfestations of empty concrete elevator silos. A Mobile Heat Treatment Unit was used to introduce heat into silos to attain target conditions of 50°C for at least 6 h. Ventilated plastic containers with a capacity of...

  8. Saving energy resources during heat treatment - the most important problem of the branch

    Energy Technology Data Exchange (ETDEWEB)

    Zadernovskiy, V V; Firger, I V

    1980-01-01

    Natural gas fired thermal furnaces expend significantly less fuel than electric furnaces with an equal quality of metal heating. An important reserve in power reserve economy is the use of the forging heat in an article for heat treatment (TOB), where besides the power resources, metal is also saved as a result of the reduction in the volume of heating means and production spaces. From the experience in the progressive enterprises of the branch, in a number of cases it is possible to combine heating for plastic deformation with heating for primary or secondary heat treatment. Other measures are examined which save power resources in heat treatment: the use of thermal furnaces for aerodynamic heating, the use of local heat treatment, the reduction in the duration of the heat treatment processes, savings in the power carriers during heat treatment in furnaces with a roll out hearth. Fibrous refractory materials are being used more and more as fettling materials in the construction of thermal furnaces.

  9. New Nomenclatures for Heat Treatments of Additively Manufactured Titanium Alloys

    Science.gov (United States)

    Baker, Andrew H.; Collins, Peter C.; Williams, James C.

    2017-07-01

    The heat-treatment designations and microstructure nomenclatures for many structural metallic alloys were established for traditional metals processing, such as casting, hot rolling or forging. These terms do not necessarily apply for additively manufactured (i.e., three-dimensionally printed or "3D printed") metallic structures. The heat-treatment terminology for titanium alloys generally implies the heat-treatment temperatures and their sequence relative to a thermomechanical processing step (e.g., forging, rolling). These designations include: β-processing, α + β-processing, β-annealing, duplex annealing and mill annealing. Owing to the absence of a thermomechanical processing step, these traditional designations can pose a problem when titanium alloys are first produced via additive manufacturing, and then heat-treated. This communication proposes new nomenclatures for heat treatments of additively manufactured titanium alloys, and uses the distinct microstructural features to provide a correlation between traditional nomenclature and the proposed nomenclature.

  10. Racemization of Valine by Impact-Induced Heating

    Science.gov (United States)

    Furukawa, Yoshihiro; Takase, Atsushi; Sekine, Toshimori; Kakegawa, Takeshi; Kobayashi, Takamichi

    2018-03-01

    Homochirality plays an important role in all living organisms but its origin remains unclear. It also remains unclear whether such chiral molecules survived terrestrial heavy impact events. Impacts of extraterrestrial objects on early oceans were frequent and could have affected the chirality of oceanic amino acids when such amino acids accumulated during impacts. This study investigated the effects of shock-induced heating on enantiomeric change of valine with minerals such as olivine ([Mg0.9, Fe0.1]2SiO4), hematite (Fe2O3), and calcite (CaCO3). With a shock wave generated by an impact at 0.8 km/s, both d- and l-enriched valine were significantly decomposed and partially racemized under all experimental conditions. Different minerals had different shock impedances; therefore, they provided different P-T conditions for identical impacts. Furthermore, the high pH of calcite promoted the racemization of valine. The results indicate that in natural hypervelocity impacts, amino acids in shocked oceanic water would have decomposed completely, since impact velocity and the duration of shock compression and heating are typically greater in hypervelocity impact events than those in experiments. Even with the shock wave by the impact of small and decelerated projectiles in which amino acids survive, the shock heating may generate sufficient heat for significant racemization in shocked oceanic water. However, the duration of shock induced heating by small projectiles is limited and the population of such decelerated projectiles would be limited. Therefore, even though impacts of asteroids and meteorites were frequent on the prebiotic Earth, impact events would not have significantly changed the ee of proteinogenic amino acids accumulated in the entire ocean.

  11. Heat Treatment of a Casting Element of a Through Clamp to Suspension of Electric Cables on Line Post Insulators

    Directory of Open Access Journals (Sweden)

    Pezda J.

    2016-09-01

    Full Text Available Heat treatment of a casting elements poured from silumins belongs to technological processes aimed mainly at change of their mechanical properties in solid state, inducing predetermined structural changes, which are based on precipitation processes (structural strengthening of the material, being a derivative of temperature and duration of solutioning and ageing operations. The subject-matter of this paper is the issue concerning implementation of a heat treatment process, basing on selection of dispersion hardening parameters to assure improvement of technological quality in terms of mechanical properties of a clamping element of energy network suspension, poured from hypoeutectic silumin of the LM25 brand; performed on the basis of experimental research program with use of the ATD method, serving to determination of temperature range of solutioning and ageing treatments. The heat treatment performed in laboratory conditions on a component of energy network suspension has enabled increase of the tensile strength Rm and the hardness HB with about 60-70% comparing to the casting without the heat treatment, when the casting was solutioned at temperature 520 °C for 1 hour and aged at temperature 165 °C during 3 hours.

  12. Parallel Changes in H2O2 and Catalase during Thermotolerance Induced by Salicylic Acid or Heat Acclimation in Mustard Seedlings1

    Science.gov (United States)

    Dat, James F.; Lopez-Delgado, Humberto; Foyer, Christine H.; Scott, Ian M.

    1998-01-01

    Spraying mustard (Sinapis alba L.) seedlings with salicylic acid (SA) solutions between 10 and 500 μm significantly improved their tolerance to a subsequent heat shock at 55°C for 1.5 h. The effects of SA were concentration dependent, with higher concentrations failing to induce thermotolerance. The time course of thermotolerance induced by 100 μm SA was similar to that obtained with seedlings acclimated at 45°C for 1 h. We examined the hypothesis that induced thermotolerance involved H2O2. Heat shock at 55°C caused a significant increase in endogenous H2O2 and reduced catalase activity. A peak in H2O2 content was observed within 5 min of either SA treatment or transfer to the 45°C acclimation temperature. Between 2 and 3 h after SA treatment or heat acclimation, both H2O2 and catalase activity significantly decreased below control levels. The lowered H2O2 content and catalase activity occurred in the period of maximum thermoprotection. It is suggested that thermoprotection obtained either by spraying SA or by heat acclimation may be achieved by a common signal transduction pathway involving an early increase in H2O2. PMID:9536052

  13. Technical project of complex fast cycle heat treatment of hydrogenous coal preparation

    OpenAIRE

    Moiseev, V. A.; Andrienko, V. G.; Pileckij, V. G.; Urvancev, A. I.; Gvozdyakov, Dmitry Vasilievich; Gubin, Vladimir Evgenievich; Matveev, Aleksandr Sergeevich; Savostiyanova, Ludmila Viktorovna

    2015-01-01

    Problems of heat-treated milled hydrogenous coal preparation site creation in leading fast cycle heat treatment complex were considered. Conditions for effective use of electrostatic methods of heat-treated milled hydrogenous coal preparation were set. Technical project of heat treatment of milled hydrogenous coal preparation site was developed including coupling of working equipment complex on fast heat treatment and experimental samples of equipment being designed for manufacturing. It was ...

  14. Effects of heat treatment on the mechanical properties of kenaf fiber

    Energy Technology Data Exchange (ETDEWEB)

    Carada, Paulo Teodoro D. L. [Master’s student in the Graduate School of Science and Engineering, Mechanical Engineering, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe City, Kyoto Prefecture, 610-0394 (Japan); Fujii, Toru; Okubo, Kazuya [Professor in the Faculty of Science and Engineering, Department of Mechanical and Systems Engineering, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe City, Kyoto Prefecture, 610-0394 (Japan)

    2016-05-18

    Natural fibers are utilized in various ways. One specific application of it, is in the field natural fiber composite (NFC). Considerable amount of researches are conducted in this field due to rising concerns in the harmful effects of synthetic materials to the environment. Additionally, these researches are done in order to overcome the drawbacks which limit the wide use of natural fiber. A way to improve NFC is to look into the reinforcing component (natural fiber). Treatments, which are classified as mechanical or chemical in nature, can be done in order to improve the performance of the natural fiber. The aim of this study is to assess the effects of heat treatment in the mechanical properties of kenaf fiber. In addition, the response of mechanical properties after exposure to high moisture environment of heat-treated kenaf fibers was observed. Heat treatment was done for one hour with the following heating temperatures: 140, 160, 180, and 200 °C. X-ray diffraction analysis was done to calculate the crystallinity index of kenaf fibers after heat treatment. The results showed that increase in tensile strength can be attained when kenaf fibers are heat treated at 140 °C. However, the tensile modulus showed inconsistency with respect to heat treatment temperature. The computed crystallinity index of the fiber matched the tensile strength observed in non-treated and heat-treated kenaf fibers. The results obtained in this study can be used for applications where heat treatment on kenaf fibers is needed.

  15. High-efficiency Agrobacterium rhizogenes-mediated transformation of heat inducible sHSP18.2-GUS in Nicotiana tabacum.

    Science.gov (United States)

    Chen, Shih-Cheng; Liu, Hui-Wen; Lee, Kung-Ta; Yamakawa, Takashi

    2007-01-01

    The chimerical gene, Arabidopsis thaliana sHSP18.2 promoter fused to E. coli gusA gene, was Agrobacterium rhizogenes-mediated transformed into Nicotiana tabacum as a heat-regulatable model, and the thermo-inducible expression of GUS activity in N. tabacum transgenic hairy roots was profiled. An activation of A. rhizogenes with acetosyringone (AS) before cocultured with tobacco's leaf disc strongly promoted transgenic hairy roots formation. Transgenic hairy roots formation efficiency of A. rhizogenes precultured with 200 microM AS supplementation was 3.1-fold and 7.5-fold, respectively, compared to the formation efficiency obtained with and without AS supplementation in coculture. Transgenic hairy roots transformed with different AS concentration exhibited a similar pattern of thermo-inducibility after 10 min to 3 h heat treatments detected by GUS expression. The peak of expressed GUS specific activity, 399,530 pmol MUG per mg total protein per min, of the transgenic hairy roots was observed at 48 h after 3 h of 42 degrees C heat treatment, and the expressed GUS specific activity was 7-26 times more than that reported in A. thaliana, tobacco BY-2 cells and Nicotiana plumbaginifolia. Interference caused by AS supplementation on the growth of transgenic hairy roots, time-course of GUS expression and its expression level were not observed.

  16. Effect of a Traditional Herbal Prescription, Kyung-Ok-Ko, on Male Mouse Spermatogenic Ability after Heat-Induced Damage

    Directory of Open Access Journals (Sweden)

    Deok-Sang Hwang

    2015-01-01

    Full Text Available Kyung-Ok-Ko (KOK, a well-known traditional Korean medicinal formula, has long been used to invigorate the essential qi. This use of KOK may be associated with reproductive ability as a more modern concept. The protective effect of KOK was evaluated against deterioration of testicular function induced by heat exposure in male mice. Male fertility was disrupted by scrotal heat stress at 43°C for 5 weeks. KOK (0.25, 0.50, and 2.00 g/kg/day was administered orally at 3 h after the stress. To evaluate the protective effect of KOK, body weight, testicular weight, sperm count, sperm motility, and histopathological changes in the testes were evaluated. KOK-treated mice significantly recovered their general health, as evidenced by body weight. KOK-treated mice also showed significantly higher testes weights, sperm counts, and sperm motility than did the heat stress group. KOK-treated mice significantly recovered the morphological appearance of the seminiferous tubules and seminiferous epithelium. Furthermore, KOK-treated mice significantly increased antioxidant enzyme activities and reduced the protein expressions of apoptosis in the testes. KOK significantly protects against heat-induced damage to testicular function in male mice by inhibiting oxidative stress and apoptosis, indicating that KOK may be an effective agent for treatment of heat-induced male infertility.

  17. Preventing hydrogen-including cracking after welding of pressure vessel steels by use of low temperature postweld heat treatments

    International Nuclear Information System (INIS)

    Schulze, G.

    1977-01-01

    Based on extensive literature evaluations and an experimental programme, the possibilities and limits of avoiding hydrogen-induced cracking in welded joints through heat treatment are presented. The author refers to a report by J.S. Caplan and E. Landerman, published in 1976. (orig./IHOE) [de

  18. Effect of heat treatment on structure and magnetic properties

    Indian Academy of Sciences (India)

    Fe46Co35Ni19/CNTs nanocomposites have been prepared by an easy two-step route including adsorption and heat treatment processes. We investigated the effect of heat treatment conditions on structure, morphology, nanoparticle sizes and magnetic properties of the Fe46Co35Ni19 alloy nanoparticles attached on the ...

  19. Gibberellic Acid-Induced Aleurone Layers Responding to Heat Shock or Tunicamycin Provide Insight into the N-Glycoproteome, Protein Secretion, and Endoplasmic Reticulum Stress

    DEFF Research Database (Denmark)

    Barba Espin, Gregorio; Dedvisitsakul, Plaipol; Hägglund, Per

    2014-01-01

    respond to gibberellic acid by secreting an array of proteins and provide a unique system for the analysis of plant protein secretion. Perturbation of protein secretion in gibberellic acid-induced aleurone layers by two independent mechanisms, heat shock and tunicamycin treatment, demonstrated overlapping...... and secretion, such as calreticulin, protein disulfide isomerase, proteasome subunits, and isopentenyl diphosphate isomerase. Sixteen heat shock proteins in 29 spots showed diverse responses to the treatments, with only a minority increasing in response to heat shock. The majority, all of which were small heat...... shock proteins, decreased in heat-shocked aleurone layers. Additionally, glycopeptide enrichment and N-glycosylation analysis identified 73 glycosylation sites in 65 aleurone layer proteins, with 53 of the glycoproteins found in extracellular fractions and 36 found in intracellular fractions...

  20. Heat treatment of cathodic arc deposited amorphous hard carbon films

    Energy Technology Data Exchange (ETDEWEB)

    Anders, S.; Ager, J.W. III; Brown, I.G. [and others

    1997-02-01

    Amorphous hard carbon films of varying sp{sup 2}/sp{sup 3} fractions have been deposited on Si using filtered cathodic are deposition with pulsed biasing. The films were heat treated in air up to 550 C. Raman investigation and nanoindentation were performed to study the modification of the films caused by the heat treatment. It was found that films containing a high sp{sup 3} fraction sustain their hardness for temperatures at least up to 400 C, their structure for temperatures up to 500 C, and show a low thickness loss during heat treatment. Films containing at low sp{sup 3} fraction graphitize during the heat treatment, show changes in structure and hardness, and a considerable thickness loss.

  1. Photo-induced-heat localization on nanostructured metallic glasses

    Science.gov (United States)

    Uzun, Ceren; Kahler, Niloofar; Grave de Peralta, Luis; Kumar, Golden; Bernussi, Ayrton A.

    2017-09-01

    Materials with large photo-thermal energy conversion efficiency are essential for renewable energy applications. Photo-excitation is an effective approach to generate controlled and localized heat at relatively low excitation optical powers. However, lateral heat diffusion to the surrounding illuminated areas accompanied by low photo-thermal energy conversion efficiency remains a challenge for metallic surfaces. Surface nanoengineering has proven to be a successful approach to further absorption and heat generation. Here, we show that pronounced spatial heat localization and high temperatures can be achieved with arrays of amorphous metallic glass nanorods under infrared optical illumination. Thermography measurements revealed marked temperature contrast between illuminated and non-illuminated areas even under low optical power excitation conditions. This attribute allowed for generating legible photo-induced thermal patterns on textured metallic glass surfaces.

  2. Microstructure, in vitro corrosion and cytotoxicity of Ca-P coatings on ZK60 magnesium alloy prepared by simple chemical conversion and heat treatment.

    Science.gov (United States)

    Li, Kaikai; Wang, Bing; Yan, Biao; Lu, Wei

    2013-09-01

    Magnesium alloys are potential biodegradable materials for biomedical application. But their poor corrosion resistance may result in premature failure of implants. In this study, to solve this problem, Ca-P coatings were prepared on ZK60 magnesium alloy by a simple chemical conversion process and heat treatment. Surface characterization showed that a flake-like Dicalcium phosphate dihydrate (DCPD) (CaHPO₄·2H₂O) coating was formed on ZK60 alloy by the chemical conversion process. DCPD transformed into Dicalcium phosphate anhydrous (DCPa) (CaHPO₄) and Ca₂P₂O₇ after heat treatment. Results of potentiodynamic polarization showed the corrosion potential of ZK60 was increased from -1666 mV to -1566 mV with DCPD coating, while -1515 mV was obtained after heat treatment. The corrosion current density of ZK60 was measured to be reduced from 35 µA/cm² to 3.5 µA/cm² with DCPD coating, while a further reduction to 1 µA/cm² was observed after heat treatment. This indicated that the coatings improved the substrate corrosion resistance significantly, and apparently, the heat-treated coating had a higher corrosion resistance. Immersion test demonstrated that both the coatings could provide protection for the substrate and the heat-treated coating could induce deposition of bone-like apatite. Cytotoxicity evaluation revealed that none of the samples induced toxicity to L-929 cells after 1- and 3-day culture. The cytocompatibility of ZK60 was improved by the coatings, with the following sequence: uncoated ZK60 < DCPD-coated ZK60 < heat-treated coating.

  3. Effects of Heat Stress Treatment on Age-dependent Unfolded Protein Response in Different Types of Skeletal Muscle.

    Science.gov (United States)

    Tamura, Yuki; Matsunaga, Yutaka; Kitaoka, Yu; Hatta, Hideo

    2017-03-01

    Mitochondrial and endoplasmic reticulum (ER) stress, and subsequently activated responses (mitochondrial/ER unfolded protein responses; UPRmt/UPRER), are involved in the pathogenesis of sarcopenia. To extend both basic and translational knowledge, we examined (i) whether age-induced mitochondrial and ER stress depend on skeletal muscle type in mice and (ii) whether heat stress treatment, a suggested strategy for sarcopenia, improves age-induced mitochondrial and ER stress. Aged (21-month-old) mice showed more severe mitochondrial stress and UPRmt than young (12-week-old) mice, based on increased oxidative stress, mitochondrial proteases, and mitochondrial E3 ubiquitin ligase. The aged mice also showed ER stress and UPRER, based on decreased ER enzymes and increased ER stress-related cell death. These changes were much more evident in soleus muscle than in gastrocnemius and plantaris muscles. After daily heat stress treatment (40 °C chamber for 30 minutes per day) for 4 weeks, mice showed remarkable improvements in age-related changes in soleus muscle. Heat stress had only minor effects in gastrocnemius and plantaris muscles. Based on these findings, age-associated mitochondrial stress, ER stress, and UPRmt/ER vary qualitatively with skeletal muscle type. Our results suggest a molecular basis for the beneficial effects of heat stress on muscle atrophy with age in soleus muscle. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Fabrication techniques to eliminate postweld heat treatment

    International Nuclear Information System (INIS)

    Lochhead, J.C.

    1978-01-01

    Postweld heat treatments to reduce residual stresses (stress relief operations) have been a common practice in the pressure vessel industry for a large number of years. A suitable heat treatment operation can, in particular for low alloy steels, have additional beneficial effects, i.e. a reduction in peak hardness values in the heat-affected zone, an improvement in weld metal properties, and a lowering of the adverse effects of the welding process on the mechanical properties of the parent material adjacent to the weld metal. However, continuing studies in the field of brittle fracture, improved parent materials, and more sophisticated nondestructive testing techniques have led to the elimination of such a practice in ever-increasing thickness ranges and types of material. For instance, the recently issued BS 5500 compared with BS 1113 (1969) lifts the thickness limit requiring stress relief in certain circumstances from 19 to 35mm for C steels. With respect to materials the CEGB has stated that as a result of successful operational experience it will no longer be necessary to postweld heat treat butt welds in 2 1/4 Cr-1Mo tubes of certain dimensions. Despite this trend, over a period of years a number of instances have arisen where, because of some factor, postweld heat treatment, although perhaps desirable, is not possible. This Paper describes several such examples. It must be noted that the examples quoted consist of relatively important and major items. It has been necessary within the confines of this Paper to condense the reports. It is hoped that no significant factors have been omitted. (author)

  5. Effect of heat treatment temperature on binder thermal conductivities

    International Nuclear Information System (INIS)

    Wagner, P.

    1975-12-01

    The effect of heat treatment on the thermal conductivities of a pitch and a polyfurfuryl alcohol binder residue was investigated. Graphites specially prepared with these two binders were used for the experiments. Measured thermal conductivities were treated in terms of a two-component system, and the binder thermal conductivities were calculated. Both binder residues showed increased thermal conductivity with increased heat treatment temperature

  6. Practical Considerations for Thermal Stresses Induced by Surface Heating

    International Nuclear Information System (INIS)

    Blanchard, James P.

    2003-01-01

    Rapid surface heating can induce large stresses in solids. A relatively simple model, assuming full constraint in two dimensions and no constraint in the third dimension, can adequately model stresses in a wide variety of situations. This paper derives this simple model, and supports it with criteria for its validity. Phenomena that are considered include non-zero penetration depths for the heat deposition, spatial non-uniformity in the surface heating, and elastic waves. Models for each of these cases, using simplified geometries, are used to develop quantitative limits for their applicability

  7. Development of Design Criteria for Fluid Induced Structural Vibrations in Steam Generators and Heat Exchangers

    International Nuclear Information System (INIS)

    Uvan Catton; Dhir, Vijay K.; Deepanjan Mitra; Omar Alquaddoomi; Pierangelo Adinolfi

    2004-01-01

    Flow-induced vibration in heat exchangers has been a major cause of concern in the nuclear industry for several decades. Many incidents of failure of heat exchangers due to apparent flow-induced vibration have been reported through the USNRC incident reporting system. Almost all heat exchangers have to deal with this problem during their operation. The phenomenon has been studied since the 1970s and the database of experimental studies on flow-induced vibration is constantly updated with new findings and improved design criteria for heat exchangers

  8. Impact of Heat-Shock Treatment on Yellowing of Pak Choy Leaves

    Institute of Scientific and Technical Information of China (English)

    WANG Xiang-yang; SHEN Lian-qing; YUAN Hai-na

    2004-01-01

    The physiological mechanism of maintaining the green colour of pak choy leaves (Brassica rapa var chinensis) with heat-shock treatment was studied. Chlorophyll in the outer leaves of pak choy degraded rapidly during storage at ambient temperature (20 ± 2℃), a slight yellow appeared. Heat-shock treatment (46- 50℃) had a mild effect on maintaining the green colour of outer leaves. Normal chlorophyll degradation was associated with a binding of chlorophyll with chlorophyll-binding-protein preceding chlorophyll breakdown.Heat-shock treatment was found to reduce the binding-capacity between chlorophyllbinding-protein and chlorophyll. In the chlorophyll degradation pathway, pheide dioxygenase was synthesized during leaf senescence which was considered to be a key enzyme in chlorophyll degradation. Activity of this enzyme was reduced following heat-shock treatment, which might explain the observed reduction in chlorophyll breakdown. Two groups of heat-shock proteins were detected in treated leaves, the first group containing proteins from 54KDa to 74 Kda, and the second group contained proteins from 15 KDa to 29KDa. Heat-shock treatment was also found to retard the decline of glucose and fructose (the main energy substrates) of outer leaves.

  9. Effects of heat treatment on the radiosensitivity of Salmonellae

    International Nuclear Information System (INIS)

    Choi, E.H.; Yang, J.S.; Lee, S.R.

    1978-01-01

    When the food poisoning bacteria Salmonella enteritidis and S. typhimurium were treated with radiation (cobalt-60 γ-rays) and heat (10 minutes at 45 0 C or 50 0 C), their sterilizing effect was revealed differently depending on the order of treatments. Post-irradiation heating showed a synergistic effect whereas pre-irradiation heating revealed the opposite effect and the effects differed slightly with heating temperature. (author)

  10. Novel magnetic heating probe for multimodal cancer treatment.

    Science.gov (United States)

    Kan-Dapaah, Kwabena; Rahbar, Nima; Soboyejo, Wole

    2015-05-01

    Multifunctional materials consisting of polymers and magnetic nanoparticles (MNPs) are highly sought after in the field of biomedical engineering. These materials offer new opportunities for the development of novel cancer treatment modalities that can increase the efficacy of cancer therapy. In this paper, a novel probe for multimodal cancer treatment is proposed and analyzed. The probe is essentially a cannula with two main parts: a distal heat generating tip made of a magnetic nanocomposite and a proximal insulated shaft. A description of the concept and functional operations of the probe is presented. In an effort to assess its feasibility, the authors evaluated the ability of probe tip (made of PMMA-Fe3O4 nanocomposite) to generate heat in biological tissue using alternating magnetic field (AMF) parameters (field strength and frequency) that are acceptable for human use. Heat generation by MNPs was determined using the linear response theory. The effects of Fe3O4 volume fraction on heat generation as well as treatment time on the thermal dose were studied. The finite element method model was tested for its validity using an analytical model. Lesions were revealed to have an ellipsoidal shape and their sizes were affected by treatment time. However, their shapes remained unchanged. The comparison with the analytical model showed reasonably a good agreement to within 2%. Furthermore, the authors' numerical predictions also showed reasonable agreement with the experimental results previously reported in the literature. The authors' predictions demonstrate the feasibility of their novel probe to achieve reasonable lesion sizes, during hyperthermic or ablative heating using AMF parameters (field strength and frequency) that are acceptable for human use.

  11. Flow-excursion-induced dryout at low-heat-flux

    International Nuclear Information System (INIS)

    Khatib-Rahbar, M.; Cazzoli, E.G.

    1983-01-01

    Flow-excursion-induced dryout at low-heat-flux natural-convection boiling, typical of liquid-metal fast-breeder reactors, is addressed. Steady-state calculations indicate that low-quality boiling is possible up to the point of Ledinegg instability leading to flow excursion and subsequent dryout in agreement with experimental data. A flow-regime-dependent dryout heat flux relationship based upon saturated boiling criterion is also presented. Transient analysis indicates that premature flow excursion can not be ruled out and sodium boiling is highly transient dependent. Analysis of a high-heat-flux forced convection, loss-of-flow transient shows a significantly faster flow excursion leading to dryout in excellent agreement with parallel calculations using the two-dimensional THORAX code. 17 figures

  12. Heat treatment giving a stable high temperature micro-structure in cast austenitic stainless steel

    Science.gov (United States)

    Anton, Donald L.; Lemkey, Franklin D.

    1988-01-01

    A novel micro-structure developed in a cast austenitic stainless steel alloy and a heat treatment thereof are disclosed. The alloy is based on a multicomponent Fe-Cr-Mn-Mo-Si-Nb-C system consisting of an austenitic iron solid solution (.gamma.) matrix reinforced by finely dispersed carbide phases and a heat treatment to produce the micro-structure. The heat treatment includes a prebraze heat treatment followed by a three stage braze cycle heat treatment.

  13. Maximum skin hyperaemia induced by local heating: possible mechanisms.

    Science.gov (United States)

    Gooding, Kim M; Hannemann, Michael M; Tooke, John E; Clough, Geraldine F; Shore, Angela C

    2006-01-01

    Maximum skin hyperaemia (MH) induced by heating skin to > or = 42 degrees C is impaired in individuals at risk of diabetes and cardiovascular disease. Interpretation of these findings is hampered by the lack of clarity of the mechanisms involved in the attainment of MH. MH was achieved by local heating of skin to 42-43 degrees C for 30 min, and assessed by laser Doppler fluximetry. Using double-blind, randomized, placebo-controlled crossover study designs, the roles of prostaglandins were investigated by inhibiting their production with aspirin and histamine, with the H1 receptor antagonist cetirizine. The nitric oxide (NO) pathway was blocked by the NO synthase inhibitor, NG-nitro-L-arginine methyl esther (L-NAME), and enhanced by sildenafil (prevents breakdown of cGMP). MH was not altered by aspirin, cetirizine or sildenafil, but was reduced by L-NAME: median placebo 4.48 V (25th, 75th centiles: 3.71, 4.70) versus L-NAME 3.25 V (3.10, 3.80) (p = 0.008, Wilcoxon signed rank test). Inhibition of NO production (L-NAME) resulted in a more rapid reduction in hyperaemia after heating (p = 0.011), whereas hyperaemia was prolonged in the presence of sildenafil (p = 0.003). The increase in skin blood flow was largely confined to the directly heated area, suggesting that the role of heat-induced activation of the axon reflex was small. NO, but not prostaglandins, histamine or an axon reflex, contributes to the increase in blood flow on heating and NO is also a component of the resolution of MH after heating. Copyright 2006 S. Karger AG, Basel.

  14. Noxious heat and scratching decrease histamine-induced itch and skin blood flow.

    Science.gov (United States)

    Yosipovitch, Gil; Fast, Katharine; Bernhard, Jeffrey D

    2005-12-01

    The aim of this study was to assess the effect of thermal stimuli or distal scratching on skin blood flow and histamine-induced itch in healthy volunteers. Twenty-one healthy volunteers participated in the study. Baseline measurements of skin blood flow were obtained on the flexor aspect of the forearm. These measurements were compared with skin blood flow after various stimuli: heating the skin, cooling the skin, noxious cold 2 degrees C, noxious heat 49 degrees C, and scratching via a brush with controlled pressure. Afterwards histamine iontophoresis was performed and skin blood flow and itch intensity were measured immediately after the above-mentioned stimuli. Scratching reduced mean histamine-induced skin blood flow and itch intensity. Noxious heat pain increased basal skin blood flow but reduced histamine-induced maximal skin blood flow and itch intensity. Cold pain and cooling reduced itch intensity, but neither affected histamine-induced skin blood flow. Sub-noxious warming the skin did not affect the skin blood flow or itch intensity. These findings suggest that heat pain and scratching may inhibit itch through a neurogenic mechanism that also affects skin blood flow.

  15. Shelf-life extension of bread by heat and irradiation treatment [Bangladesh

    International Nuclear Information System (INIS)

    Begum, F.; Siddique, A.K.; Choudhury, N.; Mollah, R.A.

    1994-01-01

    Bread slices were given irradiation treatment 0.5, 1.0, 1.5, and 2.0 KGy and heat treatment at 60 deg. C for 20 min to control mould growth. Mould growth was reladed at ambient temperature by 3, 4, 6 and 8 days after 0.5, 1.0, 1.5 and 2.0 KGy treatments, respectively, compared to 2 days in case of control sample and 3 days for heat treatment alone. Combination of heat with irradiation at 0.5, 1.0, 1.5 and 2.0 KGy retarded mould growth up to 4, 6, 7 an 9 days, respectively. Organoleptically, the irradiated bread slices were acceptable up to 3 to 6 days depending on the treatment. The combination method treated slices were acceptable up to 8 days. The application of radiation dose exceeding 2.0 KGy caused off flavour. Mild heat treatment and radiation in combination resulted in a synergistic antifungal effect and enhanced shelf-life of bread

  16. Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment.

    Science.gov (United States)

    Ramesh, Gopalan; Prabhu, Narayan Kotekar

    2011-04-14

    The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching, the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article, thermo-physical properties, wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment.

  17. Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment

    Directory of Open Access Journals (Sweden)

    Ramesh Gopalan

    2011-01-01

    Full Text Available Abstract The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching, the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article, thermo-physical properties, wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment.

  18. Flow-induced vibration analysis of heat exchanger and steam generator designs

    International Nuclear Information System (INIS)

    Pettigrew, M.J.; Sylvestre, Y.; Campagna, A.O.

    1977-08-01

    Tube and shell heat exchange components such as steam generators, heat exchangers and condensers are essential parts of CANDU nuclear power stations. Excessive flow-induced vibration may cause tube failures by fatigue or more likely by fretting-wear. Such failures may lead to station shutdowns that are very undesirable in terms of lost production. Hence good performance and reliability dictate a thorough flow-induced vibration analysis at the design stage. This paper presents our approach and techniques in this respect. (author)

  19. Influence of Joule heating on current-induced domain wall depinning

    Energy Technology Data Exchange (ETDEWEB)

    Moretti, Simone, E-mail: simone.moretti@usal.es; Raposo, Victor; Martinez, Eduardo [University of Salamanca, Plaza de los Caidos, 37008 Salamanca (Spain)

    2016-06-07

    The domain wall depinning from a notch in a Permalloy nanostrip on top of a SiO{sub 2}/Si substrate is studied theoretically under application of static magnetic fields and the injection of short current pulses. The influence of Joule heating on current-induced domain wall depinning is explored self-consistently by coupling the magnetization dynamics in the ferromagnetic strip to the heat transport throughout the system. Our results indicate that Joule heating plays a remarkable role in these processes, resulting in a reduction in the critical depinning field and/or in a temporary destruction of the ferromagnetic order for typically injected current pulses. In agreement with experimental observations, similar pinning-depinning phase diagrams can be deduced for both current polarities when the Joule heating is taken into account. These observations, which are incompatible with the sole contribution of spin transfer torques, provide a deeper understanding of the physics underlying these processes and establish the real scope of the spin transfer torque. They are also relevant for technological applications based on current-induced domain-wall motion along soft strips.

  20. Stability of Retained Austenite in High-Al, Low-Si TRIP-Assisted Steels Processed via Continuous Galvanizing Heat Treatments

    Science.gov (United States)

    McDermid, J. R.; Zurob, H. S.; Bian, Y.

    2011-12-01

    Two galvanizable high-Al, low-Si transformation-induced plasticity (TRIP)-assisted steels were subjected to isothermal bainitic transformation (IBT) temperatures compatible with the continuous galvanizing (CGL) process and the kinetics of the retained austenite (RA) to martensite transformation during room temperature deformation studied as a function of heat treatment parameters. It was determined that there was a direct relationship between the rate of strain-induced transformation and optimal mechanical properties, with more gradual transformation rates being favored. The RA to martensite transformation kinetics were successfully modeled using two methodologies: (1) the strain-based model of Olsen and Cohen and (2) a simple relationship with the normalized flow stress, ( {{{σ_{{flow}} - σ_{YS} }/{σ_{YS }}}} ) . For the strain-based model, it was determined that the model parameters were a strong function of strain and alloy thermal processing history and a weak function of alloy chemistry. It was verified that the strain-based model in the present work agrees well with those derived by previous workers using TRIP-assisted steels of similar composition. It was further determined that the RA to martensite transformation kinetics for all alloys and heat treatments could be described using a simple model vs the normalized flow stress, indicating that the RA to martensite transformation is stress-induced rather than strain-induced for temperatures above the Ms^{σ }.

  1. Heat Treatment of Gas-Atomized Powders for Cold Spray Deposition

    Science.gov (United States)

    Story, William A.; Brewer, Luke N.

    2018-02-01

    This communication demonstrates the efficacy of heat treatment on the improved deposition characteristics of aluminum alloy powders. A novel furnace was constructed for solutionizing of feedstock powders in an inert atmosphere while avoiding sintering. This furnace design achieved sufficiently high cooling rates to limit re-precipitation during powder cooling. Microscopy showed homogenization of the powder particle microstructures after heat treatment. Cold spray deposition efficiency with heat-treated powders substantially increased for the alloys AA2024, AA6061, and AA7075.

  2. Calculation and Designing of Up-to-Date Gas-Flame Plants for Metal Heating and Heat Treatment

    Directory of Open Access Journals (Sweden)

    V. I. Тimoshpolsky

    2008-01-01

    Full Text Available An analysis of development trends in the CIS machine-building industry and current status of the heating and heat treatment furnaces of main machine-building enterprises of the Republic of Belarus as of the 1st quarter of 2008 is given in the paper.The paper presents the most efficient engineering solutions from technological and economic point of view that concern calculation and designing of up-to-date gas-flame plants which are to be applied for modernization of the current heating and heat treatment furnaces of the machine-building enterprises in the Republic of Belarus.A thermo-technical calculation of main indices of the up-to-date gas-flame plant has been carried out in the paper.

  3. Study of heat treatment parameters for large-scale hydraulic steel gate track

    Directory of Open Access Journals (Sweden)

    Ping-zhou Cao

    2013-10-01

    Full Text Available In order to enhance external hardness and strength, a large-scale hydraulic gate track should go through heat treatment. The current design method of hydraulic gate wheels and tracks is based on Hertz contact linear elastic theory, and does not take into account the changes in mechanical properties of materials caused by heat treatment. In this study, the heat treatment parameters were designed and analyzed according to the bearing mechanisms of the wheel and track. The quenching process of the track was simulated by the ANSYS program, and the temperature variation, residual stress, and deformation were obtained and analyzed. The metallurgical structure field after heat treatment was predicted by the method based on time-temperature-transformation (TTT curves. The results show that the analysis method and designed track heat treatment process are feasible, and can provide a reference for practical projects.

  4. Irradiation and heating effects in topaz crystals from Minas Cerais, Brazil

    International Nuclear Information System (INIS)

    Albuquerque, A.R.P.L.; Isotani, S.

    1988-01-01

    The origin of the blue color induced by gamma irradiation in topaz crystals from the region around Governador Valadares, Minas Gerais, was examined through chemical analyses and heat treatments before irradiation. No correlation between impurities and the induced blue color was found. Heat treatments above 300 0 C before irradiation inhibit the formation of color. The conclusion is drawn that irradiation induced color is probably due to the presence of lattice defects. (author)

  5. Complexity of MRI induced heating on metallic leads: Experimental measurements of 374 configurations

    Directory of Open Access Journals (Sweden)

    Mendoza Gonzalo

    2008-03-01

    Full Text Available Abstract Background MRI induced heating on PM leads is a very complex issue. The widely varying results described in literature suggest that there are many factors that influence the degree of heating and that not always are adequately addressed by existing testing methods. Methods We present a wide database of experimental measurements of the heating of metallic wires and PM leads in a 1.5 T RF coil. The aim of these measurements is to systematically quantify the contribution of some potential factors involved in the MRI induced heating: the length and the geometric structure of the lead; the implant location within the body and the lead path; the shape of the phantom used to simulate the human trunk and its relative position inside the RF coil. Results We found that the several factors are the primary influence on heating at the tip. Closer locations of the leads to the edge of the phantom and to the edge of the coil produce maximum heating. The lead length is the other crucial factor, whereas the implant area does not seem to have a major role in the induced temperature increase. Also the lead structure and the geometry of the phantom revealed to be elements that can significantly modify the amount of heating. Conclusion Our findings highlight the factors that have significant effects on MRI induced heating of implanted wires and leads. These factors must be taken into account by those who plan to study or model MRI heating of implants. Also our data should help those who wish to develop guidelines for defining safe medical implants for MRI patients. In addition, our database of the entire set of measurements can help those who wish to validate their numerical models of implants that may be exposed to MRI systems.

  6. Spin heat accumulation induced by tunneling from a ferromagnet.

    Science.gov (United States)

    Vera-Marun, I J; van Wees, B J; Jansen, R

    2014-02-07

    An electric current from a ferromagnet into a nonmagnetic material can induce a spin-dependent electron temperature. Here, it is shown that this spin heat accumulation, when created by tunneling from a ferromagnet, produces a non-negligible voltage signal that is comparable to that due to the coexisting electrical spin accumulation and can give a different Hanle spin precession signature. The effect is governed by the spin polarization of the Peltier coefficient of the tunnel contact, its Seebeck coefficient, and the spin heat resistance of the nonmagnetic material, which is related to the electrical spin resistance by a spin-Wiedemann-Franz law. Moreover, spin heat injection is subject to a heat conductivity mismatch that is overcome if the tunnel interface has a sufficiently large resistance.

  7. Irradiation in combination of heat treatment of mango puree

    International Nuclear Information System (INIS)

    Noomhorm, A.; Apintanapong, M.

    1996-01-01

    The effect of irradiation with heat combination treatment on the shelf life and quality of mango puree was studied. Thermal inactivation of polyphenol oxidase enzyme at 80 degree C and 15 min. was used as a measure of adequacy of pre-heat treatment. Irradiation of mango puree after heat treatment at dosage of 0, 2, 4, 6 and 8 kGy showed no change in mc, pH, acidity, and TSS but during storage, growth of microorganisms brought changes in these values. Irradiation in combination with low temperature (5 degree C) reduced discoloration and darkening rate during storage. Irradiation dose from 0 to 8 kGy resulted in log linear reductions in microorganism levels but at 6 and 8 kGy, there was no growth of microorganisms. Products irradiated at 8 kGy showed no microorganism growth at both temperatures

  8. Analysis of flow induced vibration in heat exchangers

    International Nuclear Information System (INIS)

    Beek, A.W. van

    1977-01-01

    A description will be given of three different types of heat exchangers developed by the Dutch Nuclear Industry Group ''Neratoom'' in cooperation with TNO for the sodium-cooled fast breeder reactor SNR-300 at Kalkar. Moreover, the research related with flow induced vibrations carried out by TNO (Organization for Applied Scientific Research) will be presented. The flow induced forces on the tubes of the straight-tube steam generators were measured at the inlet and outlet section where partial crossflow occurs. With the measured flow induced forces the response of a tube was calculated as a function of the tube-to-supportbush clearances taking into account the non-linear damping effects from the sodium. The theoretical results showed that for this particular design no tube impact damage is to be expected which was confirmed later by a full scale experiment. Special attention will be devoted to the steam generator with helical-coil tube-bundles, where the sodium flows in a counter cross-flow over the tube-bundle. Extensive measurements of the power spectra of the flow induced forces were carried out since no information could be found in the literature. The vibration analysis will be presented and vibration modes of the entire bundle will be compared with experimentally obtained results. Finally a description of the vibration tests to be carried out on the intermediate heat exchanger (IHX) will be presented. (author)

  9. Analysis of flow induced vibration in heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Beek, A.W. van [Institute for Mechanical Constructions TNO, Delft (Netherlands)

    1977-12-01

    A description will be given of three different types of heat exchangers developed by the Dutch Nuclear Industry Group ''Neratoom'' in cooperation with TNO for the sodium-cooled fast breeder reactor SNR-300 at Kalkar. Moreover, the research related with flow induced vibrations carried out by TNO (Organization for Applied Scientific Research) will be presented. The flow induced forces on the tubes of the straight-tube steam generators were measured at the inlet and outlet section where partial crossflow occurs. With the measured flow induced forces the response of a tube was calculated as a function of the tube-to-supportbush clearances taking into account the non-linear damping effects from the sodium. The theoretical results showed that for this particular design no tube impact damage is to be expected which was confirmed later by a full scale experiment. Special attention will be devoted to the steam generator with helical-coil tube-bundles, where the sodium flows in a counter cross-flow over the tube-bundle. Extensive measurements of the power spectra of the flow induced forces were carried out since no information could be found in the literature. The vibration analysis will be presented and vibration modes of the entire bundle will be compared with experimentally obtained results. Finally a description of the vibration tests to be carried out on the intermediate heat exchanger (IHX) will be presented. (author)

  10. Hyperthermia-induced alteration of yeast susceptibility to mutation

    International Nuclear Information System (INIS)

    Mitchel, R.E.J.; Morrison, D.P.

    1985-01-01

    Diploid yeast (s. cerevisiae) were examined for alterations in susceptibility to induced mutation following hyperthermia treatment. In cells grown at 23 0 C, a non-lethal heat exposure (38 0 C, 30 min) markedly suppressed mutation induced by a subsequent non-killing dose of MNNG of MNU. Mutation by ENU, 8-MOP + UVA, or γ-rays was not affected. An intermediate level of mutation suppression was observed for mutation by 254nm UV or MMS. Mutation by MNNG was not suppressed by the same heat treatment delivered after the mutagen exposure. In a split dose experiment (two MNNG treatments separated by a heat exposure) no suppression of mutation was observed. Treatment with cycloheximide mimicked the effect of heat treatment. These data suggest that mutation induction by MNNG or MNU is protein synthesis dependent, i.e. an error-prone repair system is induced by exposure to MNNG or MNU but not by ENU, 8-MOP+UVA or γ-irradiation. We propose that hyperthermia treatment, by inducing stress protein synthesis at the expense of normal protein synthesis, precludes induction of this error-prone system. Therefore, in heat treated cells, DNA lesions produced by MNNG or MNU exposure must be resolved by an essentially constitutive system which is less error-prone than the inducible one

  11. Influence of heat treatment on corrosive resistance of concrete steels

    International Nuclear Information System (INIS)

    Woldan, A.; Suliga, I.; Kusinski, J.; Jazowy, R.

    1998-01-01

    The reinforcing bars are essential elements of ferro-concrete structures. During the building structure service the reinforcing bars should co-operate with surrounding concrete. Any bonding defects as well as corrosion induced strength reduction may result in construction failure. The reinforcing steel working environment is determined by concrete chemical and phase composition and surrounding environmental properties. The aggressive corrosive activity of the letter implies necessity of effective ways development to protect elements against corrosion. The effect of heat treatment, increased Si content in steel on corrosion resistance of reinforcing steel in concrete was studied in the current work. Corrosion tests and metallographic examinations proved a positive influence of hardening and Si enrichment on corrosion resistance of reinforcing bars in ferro-concrete structures. (author)

  12. Ultrasonic evaluation of heat treatment for stress relief in steel

    International Nuclear Information System (INIS)

    Bittencourt, Marcelo de S.Q.; Lamy, Carlos A.; Goncalves Filho, Orlando J.A.; Payao Filho, Joao da C.

    2000-01-01

    Residual stresses in materials arise due to the manufacturing processes. As a consequence, in the nuclear area some components must suffer a stress relief treatment according to strict criteria. Although these treatments are carefully carried on, concern with nuclear safety is constantly growing. This work proposes a nondestructive ultrasonic method to guarantee the efficiency of the heat treatment. It was used a short peened steel plate with tensile and compressive stresses which was submitted to a stress relief treatment. The results show that the proposed ultrasonic method could be used to confirm the efficiency of the stress relief heat treatment. (author)

  13. Heat transfer in tube bundles of heat exchangers with flow baffles induced forced mixing

    International Nuclear Information System (INIS)

    AbuRomia, M.M.; Chu, A.W.; Cho, S.M.

    1976-01-01

    Thermal analysis of shell-and-tube heat exchangers is being investigated through geometric modeling of the unit configuration in addition to considering the heat transfer processes taking place within the tube bundle. The governing equations that characterize the heat transfer from the shell side fluid to the tube side fluid across the heat transfer tubewalls are indicated. The equations account for the heat transfer due to molecular conduction, turbulent thermal diffusion, and forced fluid mixing among various shell side fluid channels. The analysis, though general in principle, is being applied to the Clinch River Breeder Reactor Plant-Intermediate Heat Exchanger, which utilizes flow baffles appropriately designed for induced forced fluid mixing in the tube bundle. The results of the analysis are presented in terms of the fluid and tube wall temperature distributions of a non-baffled and baffled tube bundle geometry. The former case yields axial flow in the main bundle region while the latter is associated with axial/cross flow in the bundle. The radial components of the axial/cross flow yield the necessary fluid mixing that results in reducing the thermal unbalance among the heat transfer to the allowable limits. The effect of flow maldistribution, present on the tube or shell sides of the heat exchangers, in altering the temperature field of tube bundles is also noted

  14. Online Adaptive Hyperthermia Treatment Planning During Locoregional Heating to Suppress Treatment-Limiting Hot Spots.

    Science.gov (United States)

    Kok, H Petra; Korshuize-van Straten, Linda; Bakker, Akke; de Kroon-Oldenhof, Rianne; Geijsen, Elisabeth D; Stalpers, Lukas J A; Crezee, Johannes

    2017-11-15

    Adequate tumor temperatures during hyperthermia are essential for good clinical response, but excessive heating of normal tissue should be avoided. This makes locoregional heating using phased array systems technically challenging. Online application of hyperthermia treatment planning could help to improve the heating quality. The aim of this study was to evaluate the clinical benefit of online treatment planning during treatment of pelvic tumors heated with the AMC-8 locoregional hyperthermia system. For online adaptive hyperthermia treatment planning, a graphical user interface was developed. Electric fields were calculated in a preprocessing step using our in-house-developed finite-difference-based treatment planning system. This allows instant calculation of the temperature distribution for user-selected phase-amplitude settings during treatment and projection onto the patient's computed tomographic scan for online visualization. Online treatment planning was used for 14 treatment sessions in 8 patients to reduce the patients' reports of hot spots while maintaining the same level of tumor heating. The predicted decrease in hot spot temperature should be at least 0.5°C, and the tumor temperature should decrease less than 0.2°C. These predictions were compared with clinical data: patient feedback about the hot spot and temperature measurements in the tumor region. In total, 17 hot spot reports occurred during the 14 sessions, and the alternative settings predicted the hot spot temperature to decrease by at least 0.5°C, which was confirmed by the disappearance of all 17 hot spot reports. At the same time, the average tumor temperature was predicted to change on average -0.01°C (range, -0.19°C to 0.34°C). The measured tumor temperature change was on average only -0.02°C (range, -0.26°C to 0.31°C). In only 2 cases the temperature decrease was slightly larger than 0.2°C, but at most it was 0.26°C. Online application of hyperthermia treatment planning is

  15. Effect of extraction pH on heat-induced aggregation, gelation and microstructure of protein isolate from quinoa (Chenopodium quinoa Willd)

    NARCIS (Netherlands)

    Ruiz, Geraldine Avila; Xiao, Wukai; Boekel, van Tiny; Minor, Marcel; Stieger, Markus

    2016-01-01

    The aim of this study was to determine the influence of extraction pH on heat-induced aggregation, gelation and microstructure of suspensions of protein isolates extracted from quinoa (Chenopodium quinoa Willd). Quinoa seed protein was extracted by alkaline treatment at various pH values (pH 8

  16. Desensitization of stainless steels by laser surface heat-treatment

    Energy Technology Data Exchange (ETDEWEB)

    Nakao, Yoshikuni; Nishimoto, Kazutoshi

    1987-11-01

    Laser heating was applied for the desensitization heat-treatment of the surface layer in the sensitized HAZ of Type 304 stainless steel. The degree of sensitization was examined by EPR technique and the 10 % oxalic acid electrolytic etch test. The CO/sub 2/ laser with maximum power of 1.5 kW was used for heat-treatment. Time-Temperature-Desensitization diagram (TTDS diagram) for sensitized Type 304 stainless steels were developed by calculation assuming the chromium diffusion control for desensitization which might occur when the chromium depleted zone was healed up due to dissolution of chromium carbide and chromium diffusion from the matrix being heated at the solution annealing temperatures. TTDS diagrams calculated agree fairly well with ones determined by corrosion tests. Laser irradiation conditions (e.g., Laser power, beam diameter and traveling velocity) required for desensitization of sensitized Type 304 stainless steels were calculated using additivity rule from the TTDS diagram calculated and theoretical thermal curve of laser heating derived from the heat conduction theory. After laser beam irradiated under an optimum condition predicted by calculation, the sensitized HAZ of Type 304 stainless steel restored complete resistance to intergranular corrosion.

  17. Online Adaptive Hyperthermia Treatment Planning During Locoregional Heating to Suppress Treatment-Limiting Hot Spots

    NARCIS (Netherlands)

    Kok, H. Petra; Korshuize-van Straten, Linda; Bakker, Akke; de Kroon-Oldenhof, Rianne; Geijsen, Elisabeth D.; Stalpers, Lukas J. A.; Crezee, Johannes

    2017-01-01

    Adequate tumor temperatures during hyperthermia are essential for good clinical response, but excessive heating of normal tissue should be avoided. This makes locoregional heating using phased array systems technically challenging. Online application of hyperthermia treatment planning could help to

  18. Effect of Continuous Galvanizing Heat Treatments on the Microstructure and Mechanical Properties of High Al-Low Si Transformation Induced Plasticity Steels

    Science.gov (United States)

    Bellhouse, E. M.; McDermid, J. R.

    2010-02-01

    Heat treatments were performed using an isothermal bainitic transformation (IBT) temperature compatible with continuous hot-dip galvanizing on two high Al-low Si transformation induced plasticity (TRIP)-assisted steels. Both steels had 0.2 wt pct C and 1.5 wt pct Mn; one had 1.5 wt pct Al and the other had 1 wt pct Al and 0.5 wt pct Si. Two different intercritical annealing (IA) temperatures were used, resulting in intercritical microstructures of 50 pct ferrite (α)-50 pct austenite (γ) and 65 pct α-35 pct γ. Using the IBT temperature of 465 °C, five IBT times were tested: 4, 30, 60, 90, and 120 seconds. Increasing the IBT time resulted in a decrease in the ultimate tensile strength (UTS) and an increase in the uniform elongation, yield strength, and yield point elongation. The uniform elongation was higher when using the 50 pct α-50 pct γ IA temperature when compared to the 65 pct α-35 pct γ IA temperature. The best combinations of strength and ductility and their corresponding heat treatments were as follows: a tensile strength of 895 MPa and uniform elongation of 0.26 for the 1.5 pct Al TRIP steel at the 50 pct γ IA temperature and 90-second IBT time; a tensile strength of 880 MPa and uniform elongation of 0.27 for the 1.5 pct Al TRIP steel at the 50 pct γ IA temperature and 120-second IBT time; and a tensile strength of 1009 MPa and uniform elongation of 0.22 for the 1 pct Al-0.5 pct Si TRIP steel at the 50 pct γ IA temperature and 120-second IBT time.

  19. A Study of Ballast Water Treatment Using Engine Waste Heat

    Science.gov (United States)

    Balaji, Rajoo; Yaakob, Omar; Koh, Kho King; Adnan, Faizul Amri bin; Ismail, Nasrudin bin; Ahmad, Badruzzaman bin; Ismail, Mohd Arif bin

    2018-05-01

    Heat treatment of ballast water using engine waste heat can be an advantageous option complementing any proven technology. A treatment system was envisaged based on the ballast system of an existing, operational crude carrier. It was found that the available waste heat could raise the temperatures by 25 °C and voyage time requirements were found to be considerable between 7 and 12 days to heat the high volumes of ballast water. Further, a heat recovery of 14-33% of input energies from exhaust gases was recorded while using a test rig arrangement representing a shipboard arrangement. With laboratory level tests at temperature ranges of around 55-75 °C, almost complete species mortalities for representative phytoplankton, zooplankton and bacteria were observed while the time for exposure varied from 15 to 60 s. Based on the heat availability analyses for harvesting heat from the engine exhaust gases(vessel and test rig), heat exchanger designs were developed and optimized using Lagrangian method applying Bell-Delaware approaches. Heat exchanger designs were developed to suit test rig engines also. Based on these designs, heat exchanger and other equipment were procured and erected. The species' mortalities were tested in this mini-scale arrangement resembling the shipboard arrangement. The mortalities realized were > 95% with heat from jacket fresh water and exhaust gases alone. The viability of the system was thus validated.

  20. Functional Properties of Glutinous Rice Flour by Dry-Heat Treatment.

    Directory of Open Access Journals (Sweden)

    Yang Qin

    Full Text Available Glutinous rice flour (GRF and glutinous rice starch (GRS were modified by dry-heat treatment and their rheological, thermal properties and freeze-thaw stability were evaluated. Compared with the native GRF and GRS, the water-holding ability of modified GRF and GRS were enhanced. Both the onset and peak temperatures of the modified samples increased while the endothermic enthalpy change decreased significantly (p < 0.05. Meanwhile, dry heating remarkably increased the apparent viscosities of both GRF and GRS. Importantly, compared with GRS samples, the storage modulus (G' and loss modulus (G" values of modified GRF increased more greatly and the tanδ values decreased more remarkably, indicating that the dry-heat treatment showed more impact on the GRF and a higher viscoelasticity compared with GRS. Our results suggest the dry-heat treatment of GRF is a more effective method than that of GRS, which omits the complex and tedious process for purifying GRS, and thereby has more practical applications in the food industry.

  1. Functional Properties of Glutinous Rice Flour by Dry-Heat Treatment.

    Science.gov (United States)

    Qin, Yang; Liu, Chengzhen; Jiang, Suisui; Cao, Jinmiao; Xiong, Liu; Sun, Qingjie

    2016-01-01

    Glutinous rice flour (GRF) and glutinous rice starch (GRS) were modified by dry-heat treatment and their rheological, thermal properties and freeze-thaw stability were evaluated. Compared with the native GRF and GRS, the water-holding ability of modified GRF and GRS were enhanced. Both the onset and peak temperatures of the modified samples increased while the endothermic enthalpy change decreased significantly (p < 0.05). Meanwhile, dry heating remarkably increased the apparent viscosities of both GRF and GRS. Importantly, compared with GRS samples, the storage modulus (G') and loss modulus (G") values of modified GRF increased more greatly and the tanδ values decreased more remarkably, indicating that the dry-heat treatment showed more impact on the GRF and a higher viscoelasticity compared with GRS. Our results suggest the dry-heat treatment of GRF is a more effective method than that of GRS, which omits the complex and tedious process for purifying GRS, and thereby has more practical applications in the food industry.

  2. Enhanced heat sink with geometry induced wall-jet

    Energy Technology Data Exchange (ETDEWEB)

    Hossain, Md. Mahamudul, E-mail: sohel0991@gmail.com; Tikadar, Amitav; Bari, Fazlul; Morshed, A. K. M. M. [Department of Mechanical Engineering Bangladesh University of Engineering and Technology, Dhaka-1000. Bangladesh (Bangladesh)

    2016-07-12

    Mini-channels embedded in solid matrix have already proven to be a very efficient way of electronic cooling. Traditional mini-channel heat sinks consist of single layer of parallel channels. Although mini-channel heat sink can achieve very high heat flux, its pumping requirement for circulating liquid through the channel increase very sharply as the flow velocity increases. The pumping requirements of the heat sink can be reduced by increasing its performance. In this paper a novel approach to increase the thermal performance of the mini-channel heat sink is proposed through geometry induced wall jet which is a passive technique. Geometric irregularities along the channel length causes abrupt pressure change between the channels which causes cross flow through the interconnections thus one channel faces suction and other channel jet action. This suction and jet action disrupts boundary layer causing enhanced heat transfer performance. A CFD model has been developed using commercially available software package FLUENT to evaluate the technique. A parametric study of the velocities and the effect of the position of the wall-jets have been performed. Significant reduction in thermal resistance has been observed for wall-jets, it is also observed that this reduction in thermal resistance is dependent on the position and shape of the wall jet.

  3. Simulation of Distortion and Residual Stress Development During Heat Treatment of Steel Castings

    Energy Technology Data Exchange (ETDEWEB)

    Beckermann, Christoph; Carlson, Kent

    2011-07-22

    Heat treatment and associated processing, such as quenching, are critical during high strength steel casting production. These processes must be managed closely to prevent thermal and residual stresses that may result in distortion, cracking (particularly after machining), re-work, and weld repair. The risk of casting distortion limits aggressive quenching that can be beneficial to the process and yield an improved outcome. As a result of these distortions, adjustments must be made to the casting or pattern design, or tie bars must be added. Straightening castings after heat treatments can be both time-consuming and expensive. Residual stresses may reduce a casting's overall service performance, possibly resulting in catastrophic failure. Stress relieving may help, but expends additional energy in the process. Casting software is very limited in predicting distortions during heat treatment, so corrective measures most often involve a tedious trial-and-error procedure. An extensive review of existing heat treatment residual stress and distortion modeling revealed that it is vital to predict the phase transformations and microstructure of the steel along with the thermal stress development during heat treatment. After reviewing the state-of-the-art in heat treatment residual stress and distortion modeling, an existing commercial code was selected because of its advanced capabilities in predicting phase transformations, the evolving microstructure and related properties along with thermal stress development during heat treatment. However, this software was developed for small parts created from forgings or machined stock, and not for steel castings. Therefore, its predictive capabilities for heat treatment of steel castings were investigated. Available experimental steel casting heat treatment data was determined to be of insufficient detail and breadth, and so new heat treatment experiments were designed and performed, casting and heat treating modified versions

  4. Industrial heat treatment of R-HPDC A356 automotive brake callipers

    CSIR Research Space (South Africa)

    Chauke, L

    2012-10-01

    Full Text Available Heat treatment of rheo-high pressure die cast (R-HPDC) A356 brake callipers has produced good mechanical properties on the laboratory scale. An industrial heat treatment is required to evaluate the applicability and conformance of the R-HPDC A356...

  5. THE INFLUENCE OF PRE-HEAT TREATMENT ON WHITE CAST IRONS PLASTICITY

    Directory of Open Access Journals (Sweden)

    T. M. Myronova

    2013-11-01

    Full Text Available Purpose. The development of heat treatment modes of white cast irons for structure changes in their eutectic constituent, namely in disturbing the monolithic structure of ledeburite colonies cementite structure and eutectic net continuity. Also the mentioned heat treatment modes are targeted to the eutectic net shift for the most suitable position from the point of plastic deforming. Methodology. The hypoeutectic white cast irons with 2.92…3.35 % carbon content and additionally alloyed by 3.18 % vanadium have been used as the research materials. The mentioned alloys have been pre-heat treated and hot twist tested. Findings. The research results showed that the carbide net breaking by plastic deforming leads to cast irons mechanical properties increasing but has difficulties in implementation due to the white cast irons low plasticity. The influence of different pre-heat treatment modes on structure and plasticity of white hypoeutectic cast irons have been investigated. They include the isotherm soaking under the different temperatures as well as multiply soakings and thermo-cycling. The influence of eutectic level, as well as pre heat treatment modes on different composition white cast irons hot plasticity have been investigated. Originality. It was determined that the heat treatment, which leads to double α→γ recrystallization under 860 – 950 °С and reperlitization under 720-680 °С results in significant increase of plasticity, as well as in un-alloyed and alloyed by vanadium white cast irons. It takes place due to carbide matrix phase separation in ledeburite colonies by new phase boundaries forming especially due to carbide transformations under vanadium alloying. Practical value. The implementation of pre-heat treatment with phase recrystallization resulted in hypoeutectic white cast irons plasticity increasing. The obtained level of cast iron plasticity corresponds to the one of carbide class steels, which ensures the successful

  6. Changes in protein and starch digestibility in sorghum flour during heat-moisture treatments.

    Science.gov (United States)

    Vu, Thanh-Hien; Bean, Scott; Hsieh, Chao-Feng; Shi, Yong-Cheng

    2017-11-01

    Heat-moisture treatment (HMT) has been used to modify properties of sorghum starches. However, information is limited on the effects of HMT on the digestibility of starch and the concurrent changes in protein in sorghum flour. The objectives of this research were to identify heat-moisture conditions to increase the resistant starch (RS) content of sorghum flour and investigate changes in sorghum proteins and starch structure. Sorghum flours with different moisture contents (0, 125, 200, and 300 g kg -1 w.b.) were heated at three temperatures (100, 120 and 140 °C) and times (1, 2 and 4 h). HMT of sorghum flour increased its RS level. The flour treated at 200 g kg -1 moisture and 100 °C for 4 h had a high RS content (221 g kg -1 vs. 56 g kg -1 for the untreated flour). Starch was not gelatinized when sorghum flours heated at moisture content of 200 g kg -1 or below. Sorghum protein digestibility and solubility decreased during HMT. The increase in RS of sorghum flour upon HMT was attributed to enhanced amylose-lipid complexes and heat induced structural changes in its protein fraction. HMT can be used to increase RS content in sorghum flour without gelatinizing its starch, thereby providing sorghum flour with unique food applications. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  7. Improvement of high temperature fatigue lifetime in AZ91 magnesium alloy by heat treatment

    International Nuclear Information System (INIS)

    Mokhtarishirazabad, Mehdi; Azadi, Mohammad; Hossein Farrahi, Gholam; Winter, Gerhard; Eichlseder, Wilfred

    2013-01-01

    In the present paper, an improvement in high temperature fatigue properties of the AZ91 magnesium alloy with rare earth elements has been obtained by a typical heat treatment, denoted by T6. For this objective, out-of-phase thermo-mechanical fatigue, room temperature and high temperature low cycle fatigue tests are performed to compare lifetimes. Several rare earth elements are initially added to the AZ91 alloy during a gravity casting process in permanent molds. Also, the type of the heat treatment is examined. Results of specimens with only the solution (the T4 heat treatment) and the solution with the ageing process (the T6 heat treatment) are compared under isothermal fatigue loadings. Microstructural investigations are carried out, before and after fatigue experiments to demonstrate the heat treatment effect. Results showed that both low cycle fatigue and thermo-mechanical fatigue of the alloy at high temperatures increases tremendously after the T6 heat treatment. This behavior attributes to the variation of the ductility, which was a result of microstructural changes during the heat treatment and the varying temperature in fatigue tests

  8. Improvement of high temperature fatigue lifetime in AZ91 magnesium alloy by heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtarishirazabad, Mehdi [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Azadi, Mohammad, E-mail: m_azadi@ip-co.com [Fatigue and Wear Workgroup, Irankhodro Powertrain Company (IPCO), Tehran (Iran, Islamic Republic of); Hossein Farrahi, Gholam [School of Mechanical Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Winter, Gerhard; Eichlseder, Wilfred [Chair of Mechanical Engineering, University of Leoben, Leoben (Austria)

    2013-12-20

    In the present paper, an improvement in high temperature fatigue properties of the AZ91 magnesium alloy with rare earth elements has been obtained by a typical heat treatment, denoted by T6. For this objective, out-of-phase thermo-mechanical fatigue, room temperature and high temperature low cycle fatigue tests are performed to compare lifetimes. Several rare earth elements are initially added to the AZ91 alloy during a gravity casting process in permanent molds. Also, the type of the heat treatment is examined. Results of specimens with only the solution (the T4 heat treatment) and the solution with the ageing process (the T6 heat treatment) are compared under isothermal fatigue loadings. Microstructural investigations are carried out, before and after fatigue experiments to demonstrate the heat treatment effect. Results showed that both low cycle fatigue and thermo-mechanical fatigue of the alloy at high temperatures increases tremendously after the T6 heat treatment. This behavior attributes to the variation of the ductility, which was a result of microstructural changes during the heat treatment and the varying temperature in fatigue tests.

  9. Microstructural transformation with heat-treatment of aluminum hydroxide with gibbsite structure

    International Nuclear Information System (INIS)

    Mitsui, Tomohiro; Matsui, Toshiaki; Eguchi, Koichi; Kikuchi, Ryuji

    2009-01-01

    Aluminum hydroxide with gibbsite structure was prepared, and the microstructural transformation of the sample heat-treated at various temperatures was investigated. The sample was characterized by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), thermogravimetry and differential thermal analysis (TG-DTA), and BET surface area. The shape of the grains in the prepared sample was hexagonal prism-like morphology. The prepared sample kept a metastable state of alumina phase at higher temperatures than the commercially available gibbsite powders. The prepared gibbsite grains underwent characteristic structural change depending on the calcination temperature. The transformation of the surface morphology was initiated at 400degC, leading to the formation of cracks with the direction parallel to the basal plane. After calcination at 1200degC, a large number of grooves were formed on the surface of the lateral planes. The specific structural change of gibbsite induced by the heat treatment was strongly related to the topotactic dehydration from gibbsite and subsequent phase transition to aluminum oxides. (author)

  10. Uncertainties in the estimation of specific absorption rate during radiofrequency alternating magnetic field induced non-adiabatic heating of ferrofluids

    Science.gov (United States)

    Lahiri, B. B.; Ranoo, Surojit; Philip, John

    2017-11-01

    Magnetic fluid hyperthermia (MFH) is becoming a viable cancer treatment methodology where the alternating magnetic field induced heating of magnetic fluid is utilized for ablating the cancerous cells or making them more susceptible to the conventional treatments. The heating efficiency in MFH is quantified in terms of specific absorption rate (SAR), which is defined as the heating power generated per unit mass. In majority of the experimental studies, SAR is evaluated from the temperature rise curves, obtained under non-adiabatic experimental conditions, which is prone to various thermodynamic uncertainties. A proper understanding of the experimental uncertainties and its remedies is a prerequisite for obtaining accurate and reproducible SAR. Here, we study the thermodynamic uncertainties associated with peripheral heating, delayed heating, heat loss from the sample and spatial variation in the temperature profile within the sample. Using first order approximations, an adiabatic reconstruction protocol for the measured temperature rise curves is developed for SAR estimation, which is found to be in good agreement with those obtained from the computationally intense slope corrected method. Our experimental findings clearly show that the peripheral and delayed heating are due to radiation heat transfer from the heating coils and slower response time of the sensor, respectively. Our results suggest that the peripheral heating is linearly proportional to the sample area to volume ratio and coil temperature. It is also observed that peripheral heating decreases in presence of a non-magnetic insulating shielding. The delayed heating is found to contribute up to ~25% uncertainties in SAR values. As the SAR values are very sensitive to the initial slope determination method, explicit mention of the range of linear regression analysis is appropriate to reproduce the results. The effect of sample volume to area ratio on linear heat loss rate is systematically studied and the

  11. Uncertainties in the estimation of specific absorption rate during radiofrequency alternating magnetic field induced non-adiabatic heating of ferrofluids

    International Nuclear Information System (INIS)

    Lahiri, B B; Ranoo, Surojit; Philip, John

    2017-01-01

    Magnetic fluid hyperthermia (MFH) is becoming a viable cancer treatment methodology where the alternating magnetic field induced heating of magnetic fluid is utilized for ablating the cancerous cells or making them more susceptible to the conventional treatments. The heating efficiency in MFH is quantified in terms of specific absorption rate (SAR), which is defined as the heating power generated per unit mass. In majority of the experimental studies, SAR is evaluated from the temperature rise curves, obtained under non-adiabatic experimental conditions, which is prone to various thermodynamic uncertainties. A proper understanding of the experimental uncertainties and its remedies is a prerequisite for obtaining accurate and reproducible SAR. Here, we study the thermodynamic uncertainties associated with peripheral heating, delayed heating, heat loss from the sample and spatial variation in the temperature profile within the sample. Using first order approximations, an adiabatic reconstruction protocol for the measured temperature rise curves is developed for SAR estimation, which is found to be in good agreement with those obtained from the computationally intense slope corrected method. Our experimental findings clearly show that the peripheral and delayed heating are due to radiation heat transfer from the heating coils and slower response time of the sensor, respectively. Our results suggest that the peripheral heating is linearly proportional to the sample area to volume ratio and coil temperature. It is also observed that peripheral heating decreases in presence of a non-magnetic insulating shielding. The delayed heating is found to contribute up to ∼25% uncertainties in SAR values. As the SAR values are very sensitive to the initial slope determination method, explicit mention of the range of linear regression analysis is appropriate to reproduce the results. The effect of sample volume to area ratio on linear heat loss rate is systematically studied and

  12. Gas injection to inhibit migration during an in situ heat treatment process

    Science.gov (United States)

    Kuhlman, Myron Ira; Vinegar; Harold J.; Baker, Ralph Sterman; Heron, Goren

    2010-11-30

    Methods of treating a subsurface formation are described herein. Methods for treating a subsurface treatment area in a formation may include introducing a fluid into the formation from a plurality of wells offset from a treatment area of an in situ heat treatment process to inhibit outward migration of formation fluid from the in situ heat treatment process.

  13. Heat pump processes induced by laser radiation

    Science.gov (United States)

    Garbuny, M.; Henningsen, T.

    1980-01-01

    A carbon dioxide laser system was constructed for the demonstration of heat pump processes induced by laser radiation. The system consisted of a frequency doubling stage, a gas reaction cell with its vacuum and high purity gas supply system, and provisions to measure the temperature changes by pressure, or alternatively, by density changes. The theoretical considerations for the choice of designs and components are dicussed.

  14. Simulations of Precipitate Microstructure Evolution during Heat Treatment

    Science.gov (United States)

    Wu, Kaisheng; Sterner, Gustaf; Chen, Qing; Jou, Herng-Jeng; Jeppsson, Johan; Bratberg, Johan; Engström, Anders; Mason, Paul

    Precipitation, a major solid state phase transformation during heat treatment processes, has for more than one century been intensively employed to improve the strength and toughness of various high performance alloys. Recently, sophisticated precipitation reaction models, in assistance with well-developed CALPHAD databases, provide an efficient and cost-effective way to tailor precipitate microstructures that maximize the strengthening effect via the optimization of alloy chemistries and heat treatment schedules. In this presentation, we focus on simulating precipitate microstructure evolution in Nickel-base superalloys under arbitrary heat treatment conditions. The newly-developed TC-PRISMA program has been used for these simulations, with models refined especially for non-isothermal conditions. The effect of different cooling profiles on the formation of multimodal microstructures has been thoroughly examined in order to understand the underlying thermodynamics and kinetics. Meanwhile, validations against several experimental results have been carried out. Practical issues that are critical to the accuracy and applicability of the current simulations, such as modifications that overcome mean-field approximations, compatibility between CALPHAD databases, selection of key parameters (particularly interfacial energy and nucleation site densities), etc., are also addressed.

  15. Heat treatment trials for ITER toroidal field coils

    International Nuclear Information System (INIS)

    Matsui, Kunihiro; Hemmi, Tsutomu; Koizumi, Norikiyo; Nakajima, Hideo; Kimura, Satoshi; Nakamoto, Kazunari

    2012-01-01

    Cable-in-conduit (CIC) conductors using Nb 3 Sn strands are used in ITER toroidal fields (TF) coils. Heat treatment generates thermal strain in CIC conductors because of the difference in thermal expansion between the Nb 3 Sn strands and the stainless-steel jacket. The elongation/shrinkage of the TF conductor may make it impossible to insert a wound TF conductor into the groove of a radial plate. In addition, it is expected that the deformation of the winding due to heat treatment-based release of the residual force in the jacket may also make it impossible to insert the winding in the groove, and that correcting the winding geometry to allow insertion of the winding may influence the superconducting performance of the TF conductor. The authors performed several trials using heat treatment as the part of activities in Phase II of TF coil procurement aiming to resolve the above-mentioned technical issues, and evaluated the elongations of 0.064, 0.074 and 0.072% for the straight and curved conductors and 1/3-scale double-pancake (DP) winding, respectively. It was confirmed that correction if the deformed winding did not influence the superconducting performance of the conductor. (author)

  16. Testosterone Depletion by Castration May Protect Mice from Heat-Induced Multiple Organ Damage and Lethality

    Directory of Open Access Journals (Sweden)

    Ruei-Tang Cheng

    2010-01-01

    Full Text Available When the vehicle-treated, sham-operated mice underwent heat stress, the fraction survival and core temperature at +4 h of body heating were found to be 5 of 15 and 34.4∘C±0.3∘C, respectively. Castration 2 weeks before the start of heat stress decreased the plasma levels of testosterone almost to zero, protected the mice from heat-induced death (fraction survival, 13/15 and reduced the hypothermia (core temperature, 37.3∘C. The beneficial effects of castration in ameliorating lethality and hypothermia can be significantly reduced by testosterone replacement. Heat-induced apoptosis, as indicated by terminal deoxynucleotidyl- transferase- mediatedαUDP-biotin nick end-labeling staining, were significantly prevented by castration. In addition, heat-induced neuronal damage, as indicated by cell shrinkage and pyknosis of nucleus, to the hypothalamus was also castration-prevented. Again, the beneficial effects of castration in reducing neuronal damage to the hypothalamus as well as apoptosis in multiple organs during heatstroke, were significantly reversed by testosterone replacement. The data indicate that testosterone depletion by castration may protect mice from heatstroke-induced multiple organ damage and lethality.

  17. Excision of x-ray-induced thymine damage in chromatin from heated cells

    International Nuclear Information System (INIS)

    Warters, R.L.; Roti Roti, J.L.

    1979-01-01

    Experiments were performed to distinguish between two possible modes of hyperthermia-induced inhibition of thymine base damage excision from the DNA of CHO cells: (1) heat denaturation of excision enzyme(s) or (2) heat-induced alteration of the substrate for damage excision (chromatin). While hyperthermia (45 0 C, 15 min) had no apparent effect on the capacity of the excision enzymes to excise damage from DNA it had a dramatic effect (ca. 80% inhibition) on the ability of chromatin to serve as a substrate for unheated enzymes. These results suggest that hyperthermia-induced radiosensitization of CHO cells may be due primarily to lesions in the cellular chromatin

  18. Impact Toughness and Heat Treatment for Cast Aluminum

    Science.gov (United States)

    Lee, Jonathan A (Inventor)

    2016-01-01

    A method for transforming a cast component made of modified aluminum alloy by increasing the impact toughness coefficient using minimal heat and energy. The aluminum alloy is modified to contain 0.55%-0.60% magnesium, 0.10%-0.15% titanium or zirconium, less than 0.07% iron, a silicon-tomagnesium product ratio of 4.0, and less than 0.15% total impurities. The shortened heat treatment requires an initial heating at 1,000deg F. for up to I hour followed by a water quench and a second heating at 350deg F. to 390deg F. for up to I hour. An optional short bake paint cycle or powder coating process further increase.

  19. Effect of heat treatment operations on the Rm tensile strength of silumins

    Directory of Open Access Journals (Sweden)

    J. Pezda

    2010-10-01

    Full Text Available Owing to good technological properties, low weight and good corrosion resistance, aluminum-silicon alloys are widely used as a material for cast machinery components. State of macro- and microstructure of a castings manufactured from Al-Si alloys, which is determined by a shape and distribution of hardening phases, segregation of alloying constituents and impurities, as well as distribution of porosity, create conditions to obtainment of proper mechanical properties. These properties can be improved through modification of the alloy and performed heat treatment operations. The paper presents effect of modification and heat treatment process on the Rm tensile strength of a selected silumins (EN AB-AlSi9Cu3(Fe, EN AB-AlSi12CuNiMg, EN AB-AlSi17Cu1Ni1Mg. Investigated alloys were put to treatments of refining and modification, and next to heat treatment. Temperature range of the heat treatment operations was determined on base of curves from the ATD method. Obtained results illustrate registered curves of melting and solidification from the ATD method and strength tests. On base of performed initial tests one determined parameters of the heat treatment process (temperature and duration of solutionig and ageing treatments enabling obtainment of improved Rm tensile strength of the investigated alloys.

  20. A new paradigm for heat treatment of alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ustinovshikov, Y., E-mail: ust@ftiudm.ru

    2014-11-25

    Highlights: • The sign of the ordering energy in alloys varies with the temperature. • Each temperature of heating leads to formation of its characteristic microstructure. • Quenching of alloys is a totally unnecessary and useless operation. - Abstract: The article considers the consequences in the field of heat treatment of alloys that could follow the introduction of the concept of phase transition ordering-phase separation into common use. By example of the Fe{sub 50}Cr{sub 50} alloy, industrial carbon tool steel and Ni{sub 88}Al{sub 12} alloy, it is shown that this transition occurs at a temperature, which is definite for each system, that the change of the sign of the chemical interaction between component atoms reverses the direction of diffusion fluxes in alloys, which affects changes in the type of microstructures. The discovery of this phase transition dramatically changes our understanding of the solid solution, changes the ideology of alloy heat treatment. It inevitably leads to the conclusion about the necessity of carrying out structural studies with the help of TEM in order to adjust the phase diagrams of the systems where this phase transition has been discovered. Conclusions have been made that quenching of alloys from the so-called region of the solid solution, which is usually performed before tempering (aging) is a completely unnecessary and useless operation, that the final structure of the alloy is formed during tempering (aging) no matter what the structure was before this heat treatment.

  1. Study on Spheroidization and Related Heat Treatments of Medium Carbon Alloy Steels

    Directory of Open Access Journals (Sweden)

    Harisha S. R.

    2018-01-01

    Full Text Available The importance of medium carbon steels as engineering materials is reflected by the fact that out of the vast majority of engineering grade ferrous alloys available and used in the market today, a large proportion of them are from the family of medium carbon steels. Typically medium carbon steels have a carbon range of 0.25 to 0.65% by weight, and a manganese content ranging from 0.060 to 1.65% by weight. Medium carbon steels are more resistive to cutting, welding and forming as compared to low carbon steels. From the last two decades a number of research scholars reported the use of verity of heat treatments to tailor the properties of medium carbon steels. Spheroidizing is the novel industrial heat treatment employed to improve formability and machinability of medium/high carbon low alloy steels. This exclusive study covers procedure, the effects and possible outcomes of various heat treatments on medium carbon steels. In the present work, other related heat treatments like annealing and special treatments for property alterations which serve as pretreatments for spheroidizing are also reviewed. Medium carbon steels with property alterations by various heat treatment processes are finding increased responsiveness in transportation, aerospace, space, underwater along with other variegated fields. Improved tribological and mechanical properties consisting of impact resistance, stiffness, abrasion and strength are the main reasons for the increased attention of these steels in various industries. In the present scenario for the consolidation of important aspects of various heat treatments and effects on mechanical properties of medium carbons steel, a review of different research papers has been attempted. This review may be used as a guide to provide practical data for heat treatment industry, especially as a tool to enhance workability and tool life.

  2. Grain Refinement of Low Carbon Martensitic Steel by Heat Treatment

    Directory of Open Access Journals (Sweden)

    N. V. Kolebina

    2015-01-01

    Full Text Available The low-carbon steels have good corrosion and technological properties. Hot deformation is the main operation in manufacturing the parts from these steels. So one of the important properties of the material is a property of plasticity. The grain size significantly influences on the ductility properties of steel. The grain size of steel depends on the chemical composition of the crystallization process, heat treatment, and steel machining. There are plenty methods to have grain refinement. However, taking into account the large size of the blanks for the hydro turbine parts, the thermal cycling is an advanced method of the grain refinement adaptable to streamlined production. This work experimentally studies the heat treatment influence on the microstructure of the low-carbon 01X13N04 alloy steel and proposes the optimal regime of the heat treatment to provide a significantly reduced grain size. L.M. Kleiner, N.P. Melnikov and I.N. Bogachyova’s works focused both on the microstructure of these steels and on the influence of its parameters on the mechanical properties. The paper focuses mainly on defining an optimal regime of the heat treatment for grain refinement. The phase composition of steel and temperature of phase transformation were defined by the theoretical analysis. The dilatometric experiment was done to determine the precise temperature of the phase transformations. The analysis and comparison of the experimental data with theoretical data and earlier studies have shown that the initial sample has residual stress and chemical heterogeneity. The influence of the heat treatment on the grain size was studied in detail. It is found that at temperatures above 950 ° C there is a high grain growth. It is determined that the optimal number of cycles is two. The postincreasing number of cycles does not cause further reducing grain size because of the accumulative recrystallization process. Based on the results obtained, the thermal cycling

  3. Influence of heat treatment on magnesium alloys meant to automotive industry

    NARCIS (Netherlands)

    Popescu, G.; Moldovan, P.; Bojin, D.; Sillekens, W.H.

    2009-01-01

    The paper presents a study concerning the heat treatment realized on magnesium alloys, from AZ80 and ZK60 class. These alloys are destined to replace the conventional ferrous and aluminum alloys in automotive industry. It was realized the heat treatment, T5 - artificially aging, and it were

  4. Heat Shock Protein 90 Inhibitor (17-AAG) Induces Apoptosis and Decreases Cell Migration/Motility of Keloid Fibroblasts.

    Science.gov (United States)

    Yun, In Sik; Lee, Mi Hee; Rah, Dong Kyun; Lew, Dae Hyun; Park, Jong-Chul; Lee, Won Jai

    2015-07-01

    The regulation of apoptosis, proliferation, and migration of fibroblasts is altered in keloids. The 90-kDa heat shock protein (heat shock protein 90) is known to play a key role in such regulation. Therefore, the authors investigated whether the inhibition of heat shock protein 90 in keloid fibroblasts could induce apoptosis and attenuate keloid fibroblast proliferation and migration. The authors evaluated heat shock protein 90 expression in keloid tissues with immunohistochemistry. The authors used cell viability [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assays and annexin V/propidium iodide staining for apoptosis, a wound healing model and cell tracking system to assess cell migration, and Akt Western blotting analysis in keloid fibroblasts after inhibition of heat shock protein 90 with 17-allylaminodemethoxygeldanamycin (17-AAG). The expression of heat shock protein 90 in keloid tissues was significantly increased compared with normal tissues. The 17-AAG-treated keloid fibroblasts showed significantly decreased proliferation, promotion of apoptosis, and decreased expression of Akt. Furthermore, a dose-dependent decrease in cell migration was noted after 17-AAG treatment of keloid fibroblasts. The 17-AAG-treated keloid fibroblasts had less directionality to the wound center and migrated a shorter distance. The authors confirmed that the inhibition of heat shock protein 90 in keloid fibroblasts could promote apoptosis and attenuate proliferation and migration of keloid fibroblasts. Therefore, the authors think that the inhibition of heat shock protein 90 is a key factor in the regulation of biological processes in keloids. With further preclinical study, the authors will be able to apply these results clinically for keloid treatment.

  5. Heat treatment of a direct composite resin: influence on flexural strength

    Directory of Open Access Journals (Sweden)

    Caroline Lumi Miyazaki

    2009-09-01

    Full Text Available The purpose of this study was to evaluate the flexural strength of a direct composite, for indirect application, that received heat treatment, with or without investment. One indirect composite was used for comparison. For determination of the heat treatment temperature, thermogravimetric analysis (TGA and differential scanning calorimetry (DSC were performed, considering the initial weight loss temperature and glass transition temperature (Tg. Then, after photoactivation (600 mW/cm² - 40 s, the specimens (10 x 2 x 2 mm were heat-treated following these conditions: 170ºC for 5, 10 or 15 min, embedded or not embedded in investment. Flexural strength was assessed as a means to evaluate the influence of different heat treatment periods and investment embedding on mechanical properties. The data were analyzed by ANOVA and Tukey's test (α = 0.05. TGA showed an initial weight loss temperature of 180ºC and DSC showed a Tg value of 157°C. Heat treatment was conducted in an oven (Flli Manfredi, Italy, after 37°C storage for 48 h. Flexural strength was evaluated after 120 h at 37°C storage. The results showed that different periods and investment embedding presented similar statistical values. Nevertheless, the direct composite resin with treatments presented higher values (178.7 MPa compared to the indirect composite resin (146.0 MPa and the same direct composite submitted to photoactivation only (151.7 MPa. Within the limitations of this study, it could be concluded that the heat treatment increased the flexural strength of the direct composite studied, leading to higher mechanical strength compared to the indirect composite.

  6. Heat transfer characteristics of induced mixed convection

    International Nuclear Information System (INIS)

    Weiss, Y.; Lahav, C.; Szanto, M.; Shai, I.

    1996-01-01

    In the present work we focus our attention on the opposed Induced Mixed Convection case, i.e. the flow field structure in a vertical cylinder, closed at its bottom, opens at the top, and being heated circumferentially. The paper reports an experimental study of this complex heat transfer process. For a better understanding of the flow field and the related heat transfer process, two different experimental systems were built. The first was a flow visualization system, with water as the working fluid, while the second system enabled quantitative measurements of the temperature field in air. All the experiments were performed in the turbulent flow regime. In order to learn about all possible flow regimes, the visualization tests were conducted in three different length-to-diameter ratios (1/d=1,5,10). Quantitative measurements of the cylindrical wall temperature, as well as the radial and axial temperature profiles in the flow field, were taken in the air system. Based on the visualization observation and the measured wall temperature profile, it was found that the OIMC can be characterized by three main regimes: a mixing regime at the top, a central turbulent core and a boundary layer type of flow adjacent to the heated wall. (authors)

  7. Influences of buoyancy and thermal boundary conditions on heat transfer with naturally-induced flow

    International Nuclear Information System (INIS)

    Jackson, J.D.; Li, J.

    2002-01-01

    A fundamental study is reported of heat transfer from a vertical heated tube to air which is induced naturally upwards through it by the action of buoyancy. Measurements of local heat transfer coefficient were made using a specially designed computer-controlled power supply and measurement system for conditions of uniform wall temperature and uniform wall heat flux. The effectiveness of heat transfer proved to be much lower than for conditions of forced convection. It was found that the results could be correlated satisfactorily when presented in terms of dimensionless parameters similar to those used for free convection heat transfer from vertical surfaces provided that the heat transfer coefficients were evaluated using local fluid bulk temperature calculated utilising the measured values of flow rate induced through the system. Additional experiments were performed' with pumped flow. These covered the entire mixed convection region. It was found that the data for naturally-induced flow mapped onto the pumped flow data when presented in terms of Nusselt number ratio (mixed to forced) and buoyancy parameter. Computational simulations of the experiments were performed using an advanced computer code which incorporated a buoyancy-influenced, variable property, developing wall shear flow formulation and a low Reynolds number k-ε turbulence model. These reproduced observed behaviour quite well. (author)

  8. Evaluation of carbon diffusion in heat treatment of H13 tool steel under different atmospheric conditions

    Directory of Open Access Journals (Sweden)

    Maziar Ramezani

    2015-04-01

    Full Text Available Although the cost of the heat treatment process is only a minor portion of the total production cost, it is arguably the most important and crucial stage on the determination of material quality. In the study of the carbon diffusion in H13 steel during austenitization, a series of heat treatment experiments had been conducted under different atmospheric conditions and length of treatment. Four austenitization atmospheric conditions were studied, i.e., heat treatment without atmospheric control, heat treatment with stainless steel foil wrapping, pack carburization heat treatment and vacuum heat treatment. The results showed that stainless steel foil wrapping could restrict decarburization process, resulting in a constant hardness profile as vacuum heat treatment does. However, the tempering characteristic between these two heat treatment methods is different. Results from the gas nitrided samples showed that the thickness and the hardness of the nitrided layer is independent of the carbon content in H13 steel.

  9. Heat shock factor 1 upregulates transcription of Epstein–Barr Virus nuclear antigen 1 by binding to a heat shock element within the BamHI-Q promoter

    International Nuclear Information System (INIS)

    Wang, Feng-Wei; Wu, Xian-Rui; Liu, Wen-Ju; Liao, Yi-Ji; Lin, Sheng; Zong, Yong-Sheng; Zeng, Mu-Sheng; Zeng, Yi-Xin; Mai, Shi-Juan; Xie, Dan

    2011-01-01

    Epstein–Barr virus (EBV) nuclear antigen 1 (EBNA1) is essential for maintenance of the episome and establishment of latency. In this study, we observed that heat treatment effectively induced EBNA1 transcription in EBV-transformed B95-8 and human LCL cell lines. Although Cp is considered as the sole promoter used for the expression of EBNA1 transcripts in the lymphoblastoid cell lines, the RT-PCR results showed that the EBNA1 transcripts induced by heat treatment arise from Qp-initiated transcripts. Using bioinformatics, a high affinity and functional heat shock factor 1 (HSF1)-binding element within the − 17/+4 oligonucleotide of the Qp was found, and was determined by electrophoretic mobility shift assay and chromatin immunoprecipitation assay. Moreover, heat shock and exogenous HSF1 expression induced Qp activity in reporter assays. Further, RNA interference-mediated HSF1 gene silencing attenuated heat-induced EBNA1 expression in B95-8 cells. These results provide evidence that EBNA1 is a new target for the transcription factor HSF1.

  10. Heat shock factor 1 upregulates transcription of Epstein-Barr Virus nuclear antigen 1 by binding to a heat shock element within the BamHI-Q promoter

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Feng-Wei [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China); Wu, Xian-Rui [Department of Surgery, Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou (China); Liu, Wen-Ju; Liao, Yi-Ji [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China); Lin, Sheng [Laboratory of Integrated Biosciences, School of Life Science, Sun Yat-sen University, Guangzhou (China); Zong, Yong-Sheng; Zeng, Mu-Sheng; Zeng, Yi-Xin [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China); Mai, Shi-Juan, E-mail: maishj@sysucc.org.cn [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China); Xie, Dan, E-mail: xied@mail.sysu.edu.cn [The State Key Laboratory of Oncology in South China, Cancer Center, Sun Yat-Sen University, Guangzhou (China)

    2011-12-20

    Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is essential for maintenance of the episome and establishment of latency. In this study, we observed that heat treatment effectively induced EBNA1 transcription in EBV-transformed B95-8 and human LCL cell lines. Although Cp is considered as the sole promoter used for the expression of EBNA1 transcripts in the lymphoblastoid cell lines, the RT-PCR results showed that the EBNA1 transcripts induced by heat treatment arise from Qp-initiated transcripts. Using bioinformatics, a high affinity and functional heat shock factor 1 (HSF1)-binding element within the - 17/+4 oligonucleotide of the Qp was found, and was determined by electrophoretic mobility shift assay and chromatin immunoprecipitation assay. Moreover, heat shock and exogenous HSF1 expression induced Qp activity in reporter assays. Further, RNA interference-mediated HSF1 gene silencing attenuated heat-induced EBNA1 expression in B95-8 cells. These results provide evidence that EBNA1 is a new target for the transcription factor HSF1.

  11. Pressure effects on the structure, kinetic, and thermodynamic properties of heat-induced aggregation of protein studied by FT-IR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Y [Applied Chemistry Department, Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan); Okuno, A [Research Department 3, Central Research, Bridgestone Co. Kodaira, Tokyo 187-8531 (Japan); Kato, M, E-mail: taniguti@sk.ritsumei.ac.j [Pharmaceutical Sciences Department, Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan)

    2010-03-01

    Pressure can retrain the heat-induced aggregation and dissociate the heat-induced aggregates. We observed the aggregation-preventing pressure effect and the aggregates-dissociating pressure effect to characterize the heat-induced aggregation of equine serum albumin (ESA) by FT-IR spectroscopy. The results suggest the {alpha}-helical structure collapses at the beginning of heat-induced aggregation through the swollen structure, and then the rearrangement of structure to the intermolecular {beta}-sheet takes place through partially unfolded structure. We determined the activation volume for the heat-induced aggregation ({Delta}V'' = +93 ml/mol) and the partial molar volume difference between native state and heat-induced aggregates ({Delta}V=+32 ml/mol). This positive partial molar volume difference suggests that the heat-induced aggregates have larger internal voids than the native structure. Moreover, the positive volume change implies that the formation of the intermolecular {beta}-sheet is unfavorable under high pressure.

  12. Effects of heat treatment temperature on morphology and properties of opal crystal

    International Nuclear Information System (INIS)

    Duan Tao; China Academy of Engineering Physics, Mianyang; Peng Tongjiang; Chen Jiming; Tang Yongjian

    2008-01-01

    The monodispersed SiO 2 microspheres were synthesized by reactant mixed equally. The colloid crystal templates were assemblied by vertical sedimentation method in ethanol at certain temperatures, and the effects of the heat treatment temperature on the morphology and the properties of opal colloid crystals were investigated. SEM, TCr-DSC results indicate SiO 2 colloid templates should be heat treated at 700-800 degree C, enhancing the conglutination and mechanistic intensity of opal templates. UV-Vis analysis result indicates that the heat treatment process can remove the photonic band gap location of the opal colloid crystals, and with the heat treatment temperature increasing gradually, blue shift occurs and the gap narrows. (authors)

  13. Heat treatment effect on ductility of nickel-base alloys

    International Nuclear Information System (INIS)

    Burnakov, K.K.; Khasin, G.A.; Danilov, V.F.; Oshchepkov, B.V.; Listkova, A.I.

    1979-01-01

    Causes of low ductility of the KhN75MBTYu and KhN78T alloys were studied along with the heat treatment effects. Samples were tested at 20, 900, 1100, 1200 deg C. Large amount of inclusions was found in intercrystalline fractures of the above low-ductile alloys. The inclusions of two types took place: (α-Al 2 O 3 , FeO(Cr 2 O 3 xAl 2 O 3 )) dendrite-like ones and large-size laminated SiO 2 , FeO,(CrFe) 2 O 3 inclusions situated as separate colonies. Heat treatment of the alloys does not increase high-temperature impact strength and steel ductility. The heating above 1000 deg C leads to a partial dissolution and coagulation of film inclusions which results in an impact strength increase at room temperature

  14. Heat-induced electron emission in paraelectric phase of triglycine sulfate heated with great rate

    CERN Document Server

    Sidorkin, A A; Rogazinskaya, O V; Milovidova, S D

    2002-01-01

    One recorded experimentally heat-induced electron emission in ferroelectric triglycine sulfate (TGS) crystal within temperature range exceeding the Curie point by 10-15 K. One studied cases of q = dT/dt various rates of linear heating of specimens of TGS nominally pure crystal and TGS crystal with chromium impurity. Increase of heating rate is shown to result in increase of emission current density within the whole investigated range of temperatures. Temperature of emission occurrence depends on q rate negligibly. At the same time, temperature of emission disappearance monotonically increases with q growth. At q below 1 K/min it is localized below the Curie point. At q = 4-5 K/min the mentioned temperature reaches 60-65 deg C. In TGS crystal with chromium impurity the temperature of emission occurrence is close to the case of pure TGS. In this case, the range of emission drawing in paraphase here is by about 2 times narrower in contrast to the case of pure TGS heated with the same rate

  15. Heat Treatment of Cr- and Cr-V ledeburitic tool steels

    Directory of Open Access Journals (Sweden)

    Peter Jurči

    2014-11-01

    Full Text Available Cr- and Cr-V ledeburitic cold work tool steels belong to the most important tool materials for large series manufacturing. To enable high production stability, the tools must be heat treated before use. This overview paper brings a comprehensive study on the heat treatment of these materials, starting from the soft annealing and finishing with the tempering. Also, it describes the impact of any step of the heat treatment on the most important structural and mechanical characteristics, like the hardness, the toughness and the wear resistance. The widely used AIS D2- steel (conventionally manufactured and Vanadis 6 (PM are used as examples in most cases.

  16. Increased synaptophysin is involved in inflammation-induced heat hyperalgesia mediated by cyclin-dependent kinase 5 in rats.

    Directory of Open Access Journals (Sweden)

    Hong-Hai Zhang

    Full Text Available Mechanisms associated with cyclin-dependent kinase 5 (Cdk5-mediated heat hyperalgesia induced by inflammation remain undefined. This study was designed to examine whether Cdk5 mediates heat hyperalgesia resulting from peripheral injection of complete Freund's adjuvant (CFA in the spinal dorsal horns of rats by interacting with synaptophysin, a well known membrane protein mediating the endocytosis-exocytosis cycle of synaptic vesicles as a molecular marker associated with presynaptic vesicle membranes. The role of Cdk5 in mediating synaptophysin was examined through the combined use of behavioral approaches, imaging studies, and immunoprecipitation following CFA-induced inflammatory pain. Results showed that Cdk5 colocalized with both synaptophysin and soluble N-ethylmaleimide-sensitive factor (NSF attachment protein receptors (SNAREs consisting of VAMP-2, SNAP-25, and syntaxin 1A in spinal dorsal horn of rats. Increased synaptophysin expression of spinal cord horn neurons post intraplantar injection of CFA coincided with increased duration of heat hyperalgesia lasting from 6 h to 3 d. Intrathecal administration of roscovitine, a Cdk5 specific inhibitor, significantly depressed synaptophysin expression during peak heat hyperalgesia and heat hyperalgesia induced by peripheral injection of CFA. Data presented in this report indicated that calpain activity was transiently upregulated 6 h post CFA-treatment despite previous reports suggesting that calpain was capable of cleaving p35 into p25. Results from previous studies obtained by other laboratories demonstrated that significant changes in p35 expression levels within spinal cord horn neurons were not observed in the CFA-treated inflammatory pain model although significant upregulation of Cdk5 kinase was observed between 2 h to 7 d. Therefore, generation of p25 occurred in a calpain-independent fashion in a CFA-treated inflammatory pain model. Our results demonstrated that increased synaptophysin

  17. Dimensional Behavior of Matrix Graphite Compacts during Heat Treatments for HTGR Fuel Element Fabrication

    International Nuclear Information System (INIS)

    Lee, Young-Woo; Yeo, Seunghwan; Cho, Moon Sung

    2015-01-01

    The carbonization is a process step where the binder that is incorporated during the matrix graphite powder preparation step is evaporated and the residue of the binder is carbonized during the heat treatment at about 1073 K. This carbonization step is followed by the final high temperature heat treatment where the carbonized compacts are heat treated at 2073-2173 K in vacuum for a relatively short time (about 2 hrs). In order to develop a fuel compact fabrication technology, and for fuel matrix graphite to meet the required material properties, it is essential to investigate the relationship among the process parameters of the matrix graphite powder preparation, the fabrication parameters of fuel element green compact and the heat treatments conditions, which has a strong influence on the further steps and the material properties of fuel element. In this work, the dimensional changes of green compacts during the carbonization and final heat treatment are evaluated when compacts have different densities from different pressing conditions and different final heat treatment temperatures are employed, keeping other process parameters constant, such as the binder content, carbonization time, temperature and atmosphere (two hours ant 1073K and N2 atmosphere). In this work, the dimensional variations of green compacts during the carbonization and final heat treatment are evaluated when compacts have different densities from different pressing conditions and different final heat treatment temperatures are employed

  18. Stone heat treatment in the Early Mesolithic of southwestern Germany: Interpretation and identification.

    Directory of Open Access Journals (Sweden)

    Patrick Schmidt

    Full Text Available The Early Mesolithic of southwestern Germany, the so-called Beuronian (9600-7100 BC, is a period of important transformations in the way people lived, in their subsistence and in the stone tools they produced. One of the perhaps most spectacular re-inventions of that time is heat treatment of stones prior to their manufacture into tools. Although heat treatment has been understood as one of the defining characteristics of the Beuronian of southwestern Germany, and although its existence has been known for almost 30 years now, relatively few systematic studies on it are available. In this paper, we present such a study, aiming to shed light on two questions: (1 what technique and heating parameters were used in the Beuronian and (2 how reliable are the macroscopic proxies traditionally used to identify heat treatment in this context? We investigate these questions using a non-destructive archaeometric technique for measuring past heating temperatures of heat-treated stones and a quantitative surface roughness analysis aiming to understand the relations between surface aspect and heat treatment. These methods are applied to 46 Jurassic chert artefacts from the site Helga-Abri located in the Swabian Alb region of southwestern Germany. Our results document that an opportunistic low-investment procedure was used to heat stone, probably relying on the use of the above-ground part of regular camp-fires. We also found that the traditionally used macroscopic criteria, such as colour and surface gloss, cannot be unambiguously used to identify heat treatment in assemblages made from Jurassic chert. These findings have important implications for our understanding of the Beuronian lithic chaîne opératoire in terms of the investment in time and resources necessary, and for the refinement of archaeological techniques used to identify heat treatment in the Mesolithic of the Swabian Alb.

  19. Stone heat treatment in the Early Mesolithic of southwestern Germany: Interpretation and identification.

    Science.gov (United States)

    Schmidt, Patrick; Spinelli Sanchez, Océane; Kind, Claus-Joachim

    2017-01-01

    The Early Mesolithic of southwestern Germany, the so-called Beuronian (9600-7100 BC), is a period of important transformations in the way people lived, in their subsistence and in the stone tools they produced. One of the perhaps most spectacular re-inventions of that time is heat treatment of stones prior to their manufacture into tools. Although heat treatment has been understood as one of the defining characteristics of the Beuronian of southwestern Germany, and although its existence has been known for almost 30 years now, relatively few systematic studies on it are available. In this paper, we present such a study, aiming to shed light on two questions: (1) what technique and heating parameters were used in the Beuronian and (2) how reliable are the macroscopic proxies traditionally used to identify heat treatment in this context? We investigate these questions using a non-destructive archaeometric technique for measuring past heating temperatures of heat-treated stones and a quantitative surface roughness analysis aiming to understand the relations between surface aspect and heat treatment. These methods are applied to 46 Jurassic chert artefacts from the site Helga-Abri located in the Swabian Alb region of southwestern Germany. Our results document that an opportunistic low-investment procedure was used to heat stone, probably relying on the use of the above-ground part of regular camp-fires. We also found that the traditionally used macroscopic criteria, such as colour and surface gloss, cannot be unambiguously used to identify heat treatment in assemblages made from Jurassic chert. These findings have important implications for our understanding of the Beuronian lithic chaîne opératoire in terms of the investment in time and resources necessary, and for the refinement of archaeological techniques used to identify heat treatment in the Mesolithic of the Swabian Alb.

  20. Effect of heat treatment on microstructure and hardness of Eurofer 97, Eurofer ODS and T92 steels

    International Nuclear Information System (INIS)

    Lu, Z.; Faulkner, R.G.; Riddle, N.; Martino, F.D.; Yang, K.

    2009-01-01

    Eurofer ODS steel is a potential candidate for fusion reactor application due to its excellent swelling resistance, low thermal expansion coefficient and high temperature properties. One of the main issues is that high fluence neutron irradiation induces a significant increase of ductile-to-brittle transition temperature (DBTT) at temperatures below 400 deg. C which restricts its application. The aim of this study is to explore the methods to lower the initial DBTT of Eurofer ODS steel by heat treatment optimization. Two heats of Eurofer ODS steels with different C contents are heat-treated at different normalizing temperatures, cooling rates and tempering conditions, and are compared with Eurofer 97 and T92 steels heat-treated with similar conditions. The microstructure is characterized by optical microscopy, FEG-TEM and OIM-EBSD techniques. The effect of normalization, cooling rate and temper on grain size, precipitation, grain boundary misorientation and hardness are investigated. The influences of these properties on DBTT are discussed.

  1. Reactive oxygen species induced by heat stress during grain filling of rice (Oryza sativa L.) are involved in occurrence of grain chalkiness.

    Science.gov (United States)

    Suriyasak, Chetphilin; Harano, Keisuke; Tanamachi, Koichiro; Matsuo, Kazuhiro; Tamada, Aina; Iwaya-Inoue, Mari; Ishibashi, Yushi

    2017-09-01

    Heat stress during grain filling increases rice grain chalkiness due to increased activity of α-amylase, which hydrolyzes starch. In rice and barley seeds, reactive oxygen species (ROS) produced after imbibition induce α-amylase activity via regulation of gibberellin (GA) and abscisic acid (ABA) levels during seed germination. Here, we examined whether ROS is involved in induction of grain chalkiness by α-amylase in developing rice grains under heat stress. To elucidate the role of ROS in grain chalkiness, we grew post-anthesis rice plants (Oryza sativa L. cv. Koshihikari) under control (25°C) or heat stress (30°C) conditions with or without antioxidant (dithiothreitol) treatment. The developing grains were analyzed for expression of NADPH oxidases, GA biosynthesis genes (OsGA3ox1, OsGA20ox1), ABA catabolism genes (OsABA8'OH1, OsABA8'OH2) and an α-amylase gene (OsAmy3E), endogenous H 2 O 2 content and the grain quality. In grains exposed to heat stress, the expression of NADPH oxidase genes (especially, OsRbohB, OsRbohD, OsRbohF and OsRbohI) and the ROS content increased. Heat stress also increased the expression of OsGA3ox1, OsGA20ox1, OsABA8'OH1, OsABA8'OH2 and OsAmy3E. On the other hand, dithiothreitol treatment reduced the effects of heat stress on the expression of these genes and significantly reduced grain chalkiness induced by heat stress. These results suggest that, similar to cereal seed germination mechanism, ROS produced under heat stress is involved in α-amylase induction in maturating rice grains through GA/ABA metabolism, and consequently caused grain chalkiness. Copyright © 2017 Elsevier GmbH. All rights reserved.

  2. The effect of transcranial direct current stimulation on experimentally induced heat pain.

    Science.gov (United States)

    Aslaksen, Per M; Vasylenko, Olena; Fagerlund, Asbjørn J

    2014-06-01

    Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulatory technique that can affect human pain perception. Placebo effects are present in most treatments and could therefore also interact with treatment effects in tDCS. The present study investigated whether short-term tDCS reduced heat pain intensity, stress, blood pressure and increased heat pain thresholds in healthy volunteers when controlling for placebo effects. Seventy-five (37 females) participants were randomized into three groups: (1) active tDCS group receiving anodal tDCS (2 mA) for 7 min to the primary motor cortex (M1), (2) placebo group receiving the tDCS electrode montage but only active tDCS stimulation for 30 s and (3) natural history group that got no tDCS montage but the same pain stimulation as the active tDCS and the placebo group. Heat pain was induced by a PC-controlled thermode attached to the left forearm. Pain intensity was significantly lower in the active tDCS group when examining change scores (pretest-posttest) for the 47 °C condition. The placebo group displayed lower pain compared with the natural history group, displaying a significant placebo effect. In the 43 and 45 °C conditions, the effect of tDCS could not be separated from placebo effects. The results revealed no effects on pain thresholds. There was a tendency that active tDCS reduced stress and systolic blood pressure, however, not significant. In sum, tDCS had an analgesic effect on high-intensity pain, but the effect of tDCS could not be separated from placebo effects for medium and low pain.

  3. Loop Heat Pipe Temperature Oscillation Induced by Gravity Assist and Reservoir Heating

    Science.gov (United States)

    Ku, Jentung; Garrison, Matt; Patel, Deepak; Robinson, Frank; Ottenstein, Laura

    2015-01-01

    The Laser Thermal Control System (LCTS) for the Advanced Topographic Laser Altimeter System (ATLAS) to be installed on NASA's Ice, Cloud, and Land Elevation Satellite (ICESat-2) consists of a constant conductance heat pipe and a loop heat pipe (LHP) with an associated radiator. During the recent thermal vacuum testing of the LTCS where the LHP condenser/radiator was placed in a vertical position above the evaporator and reservoir, it was found that the LHP reservoir control heater power requirement was much higher than the analytical model had predicted. Even with the control heater turned on continuously at its full power, the reservoir could not be maintained at its desired set point temperature. An investigation of the LHP behaviors found that the root cause of the problem was fluid flow and reservoir temperature oscillations, which led to persistent alternate forward and reversed flow along the liquid line and an imbalance between the vapor mass flow rate in the vapor line and liquid mass flow rate in the liquid line. The flow and temperature oscillations were caused by an interaction between gravity and reservoir heating, and were exacerbated by the large thermal mass of the instrument simulator which modulated the net heat load to the evaporator, and the vertical radiator/condenser which induced a variable gravitational pressure head. Furthermore, causes and effects of the contributing factors to flow and temperature oscillations intermingled.

  4. Analysis of laser-induced heating in optical neuronal guidance

    DEFF Research Database (Denmark)

    Ebbesen, Christian L.; Bruus, Henrik

    2012-01-01

    Recently, it has been shown that it is possible to control the growth direction of neuronal growth cones by stimulation with weak laser light; an effect dubbed optical neuronal guidance. The effect exists for a broad range of laser wavelengths, spot sizes, spot intensities, optical intensity...... profiles and beam modulations, but it is unknown which biophysical mechanisms govern it. Based on thermodynamic modeling and simulation using published experimental parameters as input, we argue that the guidance is linked to heating. Until now, temperature effects due to laser-induced heating...

  5. Development of Design Criteria for Fluid Induced Structural Vibrations in Steam Generators and Heat Exchangers

    International Nuclear Information System (INIS)

    Catton, Ivan; Dhir, Vijay K.; Alquaddoomi, O.S.; Mitra, Deepanjan; Adinolfi, Pierangelo

    2004-01-01

    OAK-B135 Flow-induced vibration in heat exchangers has been a major cause of concern in the nuclear industry for several decades. Many incidents of failure of heat exchangers due to apparent flow-induced vibration have been reported through the USNRC incident reporting system. Almost all heat exchangers have to deal with this problem during their operation. The phenomenon has been studied since the 1970s and the database of experimental studies on flow-induced vibration is constantly updated with new findings and improved design criteria for heat exchangers. In the nuclear industry, steam generators are often affected by this problem. However, flow-induced vibration is not limited to nuclear power plants, but to any type of heat exchanger used in many industrial applications such as chemical processing, refrigeration and air conditioning. Specifically, shell and tube type heat exchangers experience flow-induced vibration due to the high velocity flow over the tube banks. Flow-induced vibration in these heat exchangers leads to equipment breakdown and hence expensive repair and process shutdown. The goal of this research is to provide accurate measurements that can help modelers to validate their models using the measured experimental parameters and thereby develop better design criteria for avoiding fluid-elastic instability in heat exchangers. The research is divided between two primary experimental efforts, the first conducted using water alone (single phase) and the second using a mixture of air or steam and water as the working fluid (two phase). The outline of this report is as follows: After the introduction to fluid-elastic instability, the experimental apparatus constructed to conduct the experiments is described in Chapter 2 along with the measurement procedures. Chapter 3 presents results obtained on the tube array and the flow loop, as well as techniques used in data processing. The project performance is described and evaluated in Chapter 4 followed by

  6. Induced thermal resistance in the mouse ear

    International Nuclear Information System (INIS)

    Law, M.P.; Coultas, P.G.; Field, S.B.

    1979-01-01

    The mouse ear (pinna) was used to investigate the effect of two hyperthermic treatments. Heating was by immersion in hot water at 43.5 0 C. A single treatment of about 50 minutes was required to cause necrosis in 50% of the ears treated. When heat treatment was given in two equal fractions the total heating time had to be increased if the interval between fractions was greater than four hours. By 24 hours a total treatment of about 100 minutes was required, indicating almost complete recovery from the first heating. Priming treatments at 43.5 0 C induced thermal resistance to a second heat treatment at 43.5 0 C. Maximum resistance was observed one day after a 20 minute priming and two days after a 40 minute priming, when the heating time had to be increased to 120 minutes, an increase by a factor of 2.4. Shorter priming treatments induced less resistance, the minimum heating time to produce an effect being two minutes. In all cases the effect decreased during the next four to five days. These results indicate that the reduced response of tissues to fractionated hyperthermia is due both to the repair of sublethal heat damage and induction of thermal resistance. (author)

  7. Heat-induced whey protein isolate fibrils: Conversion, hydrolysis, and disulphide bond formation

    NARCIS (Netherlands)

    Bolder, S.G.; Vasbinder, A.; Sagis, L.M.C.; Linden, van der E.

    2007-01-01

    Fibril formation of individual pure whey proteins and whey protein isolate (WPI) was studied. The heat-induced conversion of WPI monomers into fibrils at pH 2 and low ionic strength increased with heating time and protein concentration. Previous studies, using a precipitation method, size-exclusion

  8. Modelling the formation of heat-induced contaminants during thermal processing of food

    NARCIS (Netherlands)

    Nguyen, H.T.

    2015-01-01

    Many of our food products have undergone a heat-treatment before consumption, either at home or at the food industry. Heat treatments not only bring out desired characteristics of the food products such as flavour, texture, taste and safety aspects but also leads to the formation of undesired

  9. HEAT INDUCIBLE EXPRESSION OF ANTIFREEZE PROTEIN GENES FROM THE BEETLES Tenebrio molitor AND Microdera punctipennis.

    Science.gov (United States)

    Li, Jieqiong; Ma, Wenjing; Ma, Ji

    2016-01-01

    Antifreeze proteins (AFPs) play important roles in protecting poikilothermic organisms from cold damage. The expression of AFP genes (afps) is induced by low temperature. However, it is reported that heat can influence the expression of afps in the desert beetle Microdera punctipennis. To further detect whether heat also induce the expression of afps in other insects, and to determine the expression profiling of insect afps at different temperatures. The expression of antifreeze protein genes in the two beetles, Microdera punctipennis and Tenebrio molitor that have quite different living environment, under different temperatures were studied by using real-time quantitative PCR. Mild low temperatures (5~15 degree C), high temperature (38~47 degree C for M. punctipennis, or 37~42 degree C for T. molitor) and temperature difference (10~30 degree C) all stimulated strongly to the expression of AFP genes (Mpafps) in M. punctipennis which lives in the wild filed in desert. The mRNA level of Mpafps after M. punctipennis were exposed to these temperatures for 1h~5h was at least 30-fold of the control at 25 degree C. For T. molitor which is breeding in door with wheat bran all these temperatures stimulated significantly to the expression of Tmafps, while the extent and degree of the temperature stimulation on Tmafps expression were much lower than on Mpafps. After T. molitor were exposed to 5 degree C and 15 degree C for 1h~5h, the mRNA level of Tmafps was over 6-fold and 45-fold of the control at 25 degree C. High temperature (37~42 degree C) for 1h~3h treatments increased Tmafps mRNA level 4.8-fold of the control. Temperature difference of 10 degree C was effective in stimulating Tmafps expression. The expression of insect antifreeze protein genes both in M. punctipennis and T. molitor was induced by heat, suggesting that this phenomenon may be common in insects; the extent and degree of the influence differ in species that have different living conditions. The heat

  10. Influence of Heat Treatments on Carotenoid Content of Cherry Tomatoes

    OpenAIRE

    D'Evoli, Laura; Lombardi-Boccia, Ginevra; Lucarini, Massimo

    2013-01-01

    Tomatoes and tomato products are rich sources of carotenoids—principally lycopene, followed by β-carotene and lutein. The aim of this work was to study the effect of heat treatment on carotenoid content in cherry tomatoes. Raw and canned products were sampled and analysed; furthermore whole, skin and pulp fractions of cherry tomatoes were analysed when raw and home-processed, in order to better understand heat treatment effects. Lycopene content in canned tomatoes was two-fold higher than in ...

  11. Spin Heat Accumulation Induced by Tunneling from a Ferromagnet

    NARCIS (Netherlands)

    Vera-Marun, I.J.; Wees, B.J. van; Jansen, R.

    2014-01-01

    An electric current from a ferromagnet into a nonmagnetic material can induce a spin-dependent electron temperature. Here, it is shown that this spin heat accumulation, when created by tunneling from a ferromagnet, produces a non-negligible voltage signal that is comparable to that due to the

  12. Optimisation of the T6 heat treatment of rheocast alloy A356

    CSIR Research Space (South Africa)

    Moller, H

    2007-11-01

    Full Text Available popular solution heat treatment employed for SSM processed A356 is 6 hours at 540oC (i.e. similar to that used for permanent mould cast A356)6,7,9. Only limited work has been performed on the optimisation of the solution heat treatment of SSM processed... was not adequately studied by either Dewhirst8 or Rosso and Actis Grande5. The optimum artificial aging heat treatment proposed in both papers5,8 is 180oC for 4 hours. This was also confirmed in this work, but importantly, this applies only when natural aging...

  13. Assembly for melting and heat treatment

    International Nuclear Information System (INIS)

    Blumenfeld, M.

    1976-11-01

    Laboratory scale production of alloys having a precise alloying materials content and the exact heat treatment of metallurgical specimens are discussed. The design and assembly of two relevant instruments are described. These instruments include a laboratory vacuum induction furnace and a specially designed glass lathe, that enables even an unskilled operator to encapsulate and seal metallurgical specimens in glass capsules. (author)

  14. Effect of heat treatment on the microstructure and properties of Ni based soft magnetic alloy.

    Science.gov (United States)

    Li, Chunhong; Ruan, Hui; Chen, Dengming; Li, Kejian; Guo, Donglin; Shao, Bin

    2018-04-20

    A Ni-based alloy was heat treated by changing the temperature and ambient atmosphere of the heat treatment. Morphology, crystal structure, and physical performance of the Ni-based alloy were characterized via SEM, XRD, TEM, and PPMS. Results show that due to the heat treatment process, the grain growth of the Ni-based alloy and the removal of impurities and defects are promoted. Both the orientation and stress caused by rolling are reduced. The permeability and saturation magnetization of the alloy are improved. The hysteresis loss and coercivity are decreased. Higher heat treatment temperature leads to increased improvement of permeability and saturation magnetization. Heat treatment in hydrogen is more conducive to the removal of impurities. At the same temperature, the magnetic performance of the heat-treated alloy in hydrogen is better than that of an alloy with heat treatment in vacuum. The Ni-based alloy shows an excellent magnetic performance on 1,373 K heat treatment in hydrogen atmosphere. In this process, the µ m , B s , P u , and H c of the obtained alloy are 427 mHm -1 , 509 mT, 0.866 Jm -3 , and 0.514 Am -1 , respectively. At the same time, the resistivity of alloy decreases and its thermal conductivity increases in response to heat treatment. © 2018 Wiley Periodicals, Inc.

  15. Surface properties of heat-induced soluble soy protein aggregates of different molecular masses.

    Science.gov (United States)

    Guo, Fengxian; Xiong, Youling L; Qin, Fang; Jian, Huajun; Huang, Xiaolin; Chen, Jie

    2015-02-01

    Suspensions (2% and 5%, w/v) of soy protein isolate (SPI) were heated at 80, 90, or 100 °C for different time periods to produce soluble aggregates of different molecular sizes to investigate the relationship between particle size and surface properties (emulsions and foams). Soluble aggregates generated in these model systems were characterized by gel permeation chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Heat treatment increased surface hydrophobicity, induced SPI aggregation via hydrophobic interaction and disulfide bonds, and formed soluble aggregates of different sizes. Heating of 5% SPI always promoted large-size aggregate (LA; >1000 kDa) formation irrespective of temperature, whereas the aggregate size distribution in 2% SPI was temperature dependent: the LA fraction progressively rose with temperature (80→90→100 °C), corresponding to the attenuation of medium-size aggregates (MA; 670 to 1000 kDa) initially abundant at 80 °C. Heated SPI with abundant LA (>50%) promoted foam stability. LA also exhibited excellent emulsifying activity and stabilized emulsions by promoting the formation of small oil droplets covered with a thick interfacial protein layer. However, despite a similar influence on emulsion stability, MA enhanced foaming capacity but were less capable of stabilizing emulsions than LA. The functionality variation between heated SPI samples is clearly related to the distribution of aggregates that differ in molecular size and surface activity. The findings may encourage further research to develop functional SPI aggregates for various commercial applications. © 2015 Institute of Food Technologists®

  16. Effects of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) wood

    Science.gov (United States)

    Xianjun Li; Zhiyong Cai; Qunying Mou; Yiqiang Wu; Yuan Liu

    2011-01-01

    In this study the effect of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) was investigated. Wood specimens were subjected to heat treatment at 160, 180, 200 and 220°C for 1, 2, 3 and 4h. The results show that heat treatment resulted in a darkened color, decreased moisture performance and increased dimensional stability of...

  17. Effect of Geranylgeranylacetone on Ultraviolet Radiation Type B-Induced Cataract in Heat-Shock Transcription Factor 1 Heterozygous Mouse.

    Science.gov (United States)

    Ogasawara, Satoshi; Hashizume, Kouhei; Okuno, Takashi; Imaizumi, Toshiyasu; Inomata, Yui; Tezuka, Yu; Sanbe, Atushi; Kurosaka, Daijiro

    2017-05-01

    We investigated whether heat-shock transcription factor 1 (HSF1) was involved in ultraviolet radiation type B (UVR-B)-induced lens opacity (cataract) using HSF1 heterozygous mice. We also examined the effects of geranylgeranylacetone (GGA), an inducer of heat-shock proteins via activation of HSF, on the UVR-B-induced cataract. Male HSF1 +/- and WT mice were unilaterally exposed to UVR-B (total: 1200mJ) at 16 weeks of age. At 48 h after the last UVR-B irradiation, the lens was isolated and the induction of the cataract was quantified as the cataract area ratio (opacity area/anterior capsule). GGA was orally administered at a dosage of 500 mg/kg once a day for two days before the first UVR-B exposure until the end of the experiment (21days in total). The HSF1 expression was more greatly decreased in the lens from HSF1 +/- mice than in that from WT mice (p B exposure could mainly induce cataracts in the anterior capsule in both HSF1 +/- and WT mice, while the opacity of the lens was markedly enhanced in HSF 1+/- mice compared to that in WT mice(p (0.01). GGA treatment could prevent the induction of lens opacity by UVR-B exposure in both WT and HSF1 +/- mice as compared with the non-administration group (p B radiation was seen in lens protein levels of αA-crystallin, αB-crystallin, or γ-crystallin with or without GGA administration among all groups of mice. In contrast to the crystallins, the lens protein level of HSP25 was decreased by UVR-B exposure in both HSF1 +/- and WT mice, and was significantly recovered in WT mice by the GGA treatment (p B-induced cataracts, possibly via regulation of HSPs such as HSP25.

  18. Effect of heat treatment changes on swelling treatment of coal; Sekitan no bojun shori sayo ni oyobosu netsushori henka no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Satsuka, T.; Mashimo, K.; Wainai, T. [Nihon University, Tokyo (Japan). College of Science and Technology

    1996-10-28

    Discussions were given on effects of heat treatment at relatively low temperatures as a pretreatment for coal liquefaction on coal swelling and hydrogenolysis reaction. Taiheiyo coal was heated to 200{degree}C for one hour as a pretreatment. The attempted heating methods consisted of four steps of rapid heating (6.7{degree}C/min)quenching (20{degree}C/min), rapid heating/natural cooling (0.7{degree}C/min), heating (1.0{degree}C/min)/quenching, and heating/natural cooling. The swelling treatment was composed of adding methanol benzene into heat treated coal, and leaving it at room temperature for 24 hours. The hydrogenolysis was carried out by using a tetralin solvent and at an initial hydrogen pressure of 20 kg/cm{sup 2} and a temperature of 350{degree}C and for a time of one hour. Hydrogenolysis conversion in the heat treated coal was found lower than that of the original coal because of generation of liquefaction inactive components due to thermal polymerization. When the heat treated coal is swollen by using the solvent, gas yield from the hydrogenolysis reaction decreased due to gas suppression effect, and the conversion was lower than that of the original coal. Heat treatment suggests densification of the coal structure. Swollen coal shows no conspicuous difference in the heat treatment methods against the hydrogenolysis due to the swelling effect. 3 refs., 5 figs., 1 tab.

  19. Improvement of boiling heat transfer by radiation induced boiling enhancement

    International Nuclear Information System (INIS)

    Imai, Yasuyuki; Okamoto, Koji; Madarame, Haruki; Takamasa, Tomoji

    2003-01-01

    For nuclear reactor systems, the critical heat flux (CHF) data is very important because it limits reactor efficiency. Improvement of CHF requires that the cooling liquid can contact the heating surface, or a high-wettability, highly hydrophilic heating surface, even if a vapor bubble layer is generated on the surface. In our previous study, we confirmed that the surface wettability changed significantly or that highly hydrophilic conditions were achieved, after irradiation of 60 Co gamma ray, by the Radiation Induced Surface Activation (RISA) phenomenon. To delineate the effect of RISA on boiling phenomena, surface wettability in a high-temperature environment and critical heat flux (CHF) of metal oxides irradiated by gamma rays were investigated. A CHF experiment in the pool boiling condition was carried out under atmospheric pressure. The heating test section made of titanium was 0.2 mm in thickness, 3 mm in height, and 60 mm in length. Oxidation of the surface was carried out by plasma jetting for 40 seconds. The test section was irradiated by 60 Co gamma ray with predetermined radiation intensity and period. The CHF of oxidized titanium was improved up to 100 percent after 800 kGy 60 Co gamma ray irradiation. We call this effect Radiation Induced Boiling Enhancement (RIBE). Before we conducted the CHF experiment, contact angles of the test pieces were measured to show the relationship between wettability and CHF. The CHF in the present experiment increases will surface wettability in the same manner as shown by Liaw and Dhir's results. (author)

  20. Improvement of boiling heat transfer by radiation induced boiling enhancement

    International Nuclear Information System (INIS)

    Imai, Y.; Okamoto, K.; Madarame, H.; Takamasa, T.

    2003-01-01

    For nuclear reactor systems, the Critical Heat Flux (CHF) data is very important because it limits reactor efficiency. Improvement of CHF requires that the cooling liquid can contact the heating surface, or a high-wettability, highly hydrophilic heating surface, even if a vapor bubble layer is generated on the surface. In our previous study, we confirmed that the surface wettability changed significantly or that highly hydrophilic conditions were achieved, after irradiation of 60Co gamma ray, by the Radiation Induced Surface Activation (RISA) phenomenon. To delineate the effect of RISA on boiling phenomena, surface wettability in a high-temperature environment and Critical Heat Flux (CHF) of metal oxides irradiated by gamma rays were investigated. A CHF experiment in the pool boiling condition was carried out under atmospheric pressure. The heating test section made of titanium was 0.2mm in thickness, 3mm in height, and 60mm in length. Oxidation of the surfaces was carried out by plasma jetting for 40 seconds. The test section was irradiated by 60Co gamma ray with predetermined radiation intensity and period. The CHF of oxidized titanium was improved up to 100 percent after 800kGy 60Co gamma ray irradiation. We call this effect Radiation Induced Boiling Enhancement (RIBE). Before we conducted the CHF experiment, contact angles of the test pieces were measured to show the relationship between wettability and CHF. The CHF in the present experiment increases with surface wettability in the same manner as shown by Liaw and Dhir's results

  1. Beam-induced heating / bunch length / RF and lessons for 2012

    International Nuclear Information System (INIS)

    Metral, E.

    2012-01-01

    Beam-induced heating has been observed here and there during the 2011 run when the bunch/beam intensity was increased and/or the bunch length was reduced. These observations are first reviewed before mentioning the recent news/work performed during the shutdown. In fact, several possible sources of heating exist and only the RF heating (i.e. coming from the real part of the longitudinal impedance of the machine components) is discussed in some detail in the present paper: 1) comparing the case of a Broad-Band (BB) vs. a Narrow-Band (NB) impedance; 2) discussing the beam spectrum; 3) reminding the usual solutions to avoid/minimize the RF heating; 4) reviewing the different heat transfer mechanisms; 5) mentioning that the synchronous phase shift is a measurement of the power loss and effective impedance. The three current 'hot' topics for the LHC performance, which are the VMTSA, TDI and MKI, are then analyzed in detail and some lessons for 2012 (and after) are finally drawn

  2. A novel laboratory scale method for studying heat treatment of cake flour

    OpenAIRE

    Chesterton, AKS; Wilson, David Ian; Sadd, PI; Moggridge, Geoffrey Dillwyn

    2014-01-01

    A lab-scale method for replicating the time–temperature history experienced by cake flours undergoing heat treatment was developed based on a packed bed configuration. The performance of heat-treated flours was compared with untreated and commercially heat-treated flour by test baking a high ratio cake formulation. Both cake volume and AACC shape measures were optimal after 15 min treatment at 130 °C, though their values varied between harvests. Separate oscillatory rheometry tests of cake ba...

  3. Influence of heat treatment on the microstructure and mechanical properties of Alloy 718 base metal and weldments

    International Nuclear Information System (INIS)

    Mills, W.J.

    1979-06-01

    Effect of heat treatment on the metallurgical structure and tensile properties of three heats of Alloy 718 base metal and an Alloy 718 GTA weldment were characterized. Heat treatments employed were the conventional (ASTM A637) precipitation treatment and a modified precipitation treatment designed to improve the toughness of the weldments. The GTA weldments were characterized in the as-welded condition. Light microscopy, thin foil, and surface replica electron microscopy revealed that the microstructure of this superalloy was sensitive to heat treatment and heat-to-heat variations. The modified aging treatment resulted in a larger grain size and a more homogeneous microstructure than the conventional treatments. The morphology of the primary strengthening γ phase was found to be finer and more closely spaced in the conventionally treated condition. Room and elevated temperature tensile testing revealed that the strength of the conventionally treated alloy was generally superior to that of the modified material. The conventional aging treatment resulted in greater heat-to-heat variations in tensile properties. This behavior was correlated with variations in the microstructure resulting from the precipitation heat treatments. The precipitate morphology of the GTA weldments was sensitive to heat treatment. The Laves phase was present in the interdendritic regions of both heat-treated welds. The modified aging treatment reduced the amount of Laves phase present in the weld zone. Room and elevated temperature tensile properties of the precipitation hardened weldments were relatively insensitive to heat treatment, suggesting that reduction in Laves phase from the weld zone had essentially no effect on tensile properties. As-welded GTA weldments exhibited lower strength levels and higher ductility values than heat-treated welds

  4. The foci of DNA double strand break-recognition proteins localize with γH2AX after heat treatment

    International Nuclear Information System (INIS)

    Takahashi, Akihisa; Mori, Eiichiro; Ohnishi, Takeo

    2010-01-01

    Recently, there have been many reports concerning proteins which can recognize DNA double strand break (DSBs), and such proteins include histone H2AX phosphorylated at serine 139 (γH2AX), ataxia telangiectasia mutated (ATM) phospho-serine 1981, DNA-dependent protein kinase catalytic subunit (DNA-PKcs) phospho-threonine 2609, Nijmegen breakage syndrome 1 (NBS1) phospho-serine 343, checkpoint kinase 2 (CHK2), phospho-threonine 68, and structural maintenance of chromosomes 1 (SMC1) phospho-serine 966. Thus, it should be possible to follow the formation of DSBs and their repair using immunohistochemical methods with multiple antibodies to detect these proteins. When normal human fibroblasts (AG1522 cells) were exposed to 3 Gy of X-rays as a control, clearly discernable foci for these proteins were detected, and these foci localized with γH2AX foci. After heat treatment at 45.5 deg C for 20 min, these proteins are partially localized with γH2AX foci. Here we show that there were slight differences in the localization pattern among these proteins, such as a disappearance from the nucleus (phospho-ATM) and translocation to the cytoplasm (phospho-NBS1) at 30 min after heat treatment, and some foci (phospho-DNA-PKcs and phospho-CHK2) appeared at 8 h after heat treatment. These results are discussed from perspectives of heat-induced denaturation of proteins and formation of DSBs. (author)

  5. A Study on Infrared Local Heat Treatment for AA5083 to Improve Formability and Automotive Part Forming

    Science.gov (United States)

    Lee, Eun-Ho; Yang, Dong-Yol; Ko, SeJin

    2017-10-01

    Automotive industries are increasingly employing aluminum alloys for auto parts to reduce vehicle weight. However, the low formability of aluminum alloys has been an obstacle to their application. To resolve the formability problem, some studies involving heat treatments under laboratory conditions have been reported. However, for industrial applications, the heat treatment sequence, heating energy efficiency, and a commercial part test should be studied. This work shows an infrared (IR) local heat treatment, heating only small areas where the heat treatment is required, for an aluminum alloy to improve the formability with a reduction of heating energy. The experiment shows that the formability drastically increases when the aluminum alloy is heat treated between two forming stages, referred to as intermediate heat treatment. The microstructures of the test pieces are evaluated to identify the cause of the increase in the formability. For an industrial application, an aluminum tailgate, which cannot be manufactured without heat treatment, was successfully manufactured by the IR local heat treatment with a reduction of energy. A simulation was also conducted with a stress-based forming limit diagram, which is not affected by the strain path and heat treatment histories. The simulation gives a good prediction of the formability improvement.

  6. Fast switching of alkali atom dispensers using laser-induced heating

    International Nuclear Information System (INIS)

    Griffin, P.F.; Weatherill, K.J.; Adams, C.S.

    2005-01-01

    We show that by using an intense laser source to locally heat an alkali atom dispenser, one can generate a high flux of atoms followed by fast recovery (<100 ms) of the background pressure when the laser is extinguished. For repeated heating pulses a switch-on time for the atomic flux of 200 ms is readily attainable. This technique is suited to ultracold atom experiments using simple ultrahigh vacuum (UHV) chambers. Laser-induced heating provides a fast repetition of the experimental cycle, which, combined with low atom loss due to background gas collisions, is particularly useful for experiments involving far-off resonance optical traps, where sufficient laser power (0.5-4 W) is readily available

  7. Effect of heat moisture treatment and annealing on physicochemical ...

    African Journals Online (AJOL)

    Red sorghum starch was physically modified by annealing and heat moisture treatment. The swelling power and solubility increased with increasing temperature range (60-90°), while annealing and heatmoisture treatment decreased swelling power and solubility of starch. Solubility and swelling were pH dependent with ...

  8. Heat treatments of TiAl-Cr-V casting alloy

    International Nuclear Information System (INIS)

    Pu, Z.J.; Ma, J.L.; Wu, K.H.

    1995-01-01

    The need to investigate various kinds of fine microstructure based on casting TiAl alloy led to development of a multiple-stage heat treatment procedure. The first stage required the transformation of as-cast lamellar structure into near-gamma structure, followed by required transformation of near-gamma structure into various kinds of fine microstructure. The as-cast lamellar structure can be changed into near-gamma structure by annealing the alloy at 1,200 C for at least 50 hours. During the annealing process, two mechanisms are involved in transforming the lamellar structure into a near-gamma structure. One is the discontinuous coarsening (DC) process, and the other is the continuous coarsening (CC) process. With the near-gamma structure as an initial structure, the alloy being heat-treated in the γ + α and in the α fields can produce various kinds of microstructure with fine grain size. These microstructure significantly differ from the microstructure produced by heat-treating the deformed lamellar structure. Results of the investigation show that careful control of the time of the heat-treatment process in the single a field can produce a fine fully lamellar structure

  9. Heat deposition on the first wall due to ICRF-induced loss of fast ions in JT-60U

    International Nuclear Information System (INIS)

    Kusama, Y.; Tobita, K.; Kimura, H.; Hamamatsu, K.; Fujii, T.; Nemoto, M.; Saigusa, M.; Moriyama, S.; Tani, K.; Koide, Y.; Sakasai, A.; Nishitani, T.; Ushigusa, K.

    1995-01-01

    In JT-60U, the heat deposition on the first wall due to the ICRF-induced loss of fast ions was investigated by changing the position of the resonance layer in the ripple-trapping region. A heat spot appears on the first wall of the same major radius as the resonance layer of the ICRF waves. The broadening of the heat spot in the major radius direction is consistent with that of the resonance layer due to the Doppler broadening. The heat spot is considered to be formed by the ICRF-induced ripple-trapped loss of fast ions. Although the total ICRF-induced loss power to the heat spot is as low as 2% of the total ICRF power, the additional heat flux will become a new issue because of the localized heat deposition on the first wall. ((orig.))

  10. Evaluation of heat treatment schedules for emerald ash borer (Coleoptera: Buprestidae).

    Science.gov (United States)

    Myers, Scott W; Fraser, Ivich; Mastro, Victor C

    2009-12-01

    The thermotolerance of the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), was evaluated by subjecting larvae and prepupae to a number of time-temperature regimes. Three independent experiments were conducted during 2006 and 2007 by heating emerald ash borer infested firewood in laboratory ovens. Heat treatments were established based on the internal wood temperature. Treatments ranged from 45 to 65 degrees C for 30 and 60 min, and the ability of larvae to pupate and emerge as adults was used to evaluate the success of each treatment. A fourth experiment was conducted to examine heat treatments on exposed prepupae removed from logs and subjected to ambient temperatures of 50, 55, and 60 degrees C for 15, 30, 45, and 60 min. Results from the firewood experiments were consistent in the first experiment. Emergence data showed emerald ash borer larvae were capable of surviving a temperatures-time combination up to 60 degrees C for 30 min in wood. The 65 degrees C for 30 min treatment was, however, effective in preventing emerald ash borer emergence on both dates. Conversely, in the second experiment using saturated steam heat, complete mortality was achieved at 50 and 55 degrees C for both 30 and 60 min. Results from the prepupae experiment showed emerald ash borer survivorship in temperature-time combinations up to 55 degrees C for 30 min, and at 50 degrees C for 60 min; 60 degrees C for 15 min and longer was effective in preventing pupation in exposed prepupae. Overall results suggest that emerald ash borer survival is variable depending on heating conditions, and an internal wood temperature of 60 degrees C for 60 min should be considered the minimum for safe treatment for firewood.

  11. Heat treatment evaluation of steel ASTM A-131 grade A by X-Ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira Junior, Francisco; Feio, Luciana Gaspar; Costa, Ednelson Silva; Rodrigues, Lino Alberto Soares; Braga, Eduardo Magalhaes, E-mail: juniorferrer93@gmail.com [Universidade Federal do Pará (UFPA), Belém, PA (Brazil)

    2016-07-01

    Full text: This study evaluates the residual stress of naval steel ASTM A-131 grade A before and after heat treatment. Residual stresses were determined by the technique of X-ray diffraction (XRD). Before heat treatment the residual stress measurements were made at 36 (thirty six) points distributed in a specimen with dimensions of 400 mm long, 200 mm wide and 95 mm thick, then the plate under analysis was brought to the oven for the implementation of heat treatment. To check the performance of the heat treatment, the plate was again subjected to XRD measurements of the same points previously measured in order to compare the residual stresses. As result, there was a reduction of residual stresses with the application of heat treatment. References: [1] COLPAERT, H. Metalografia dos Produtos Siderurgicos Comuns. 4 Edição. Editora Blucher. Saõ Paulo, SP, 2008. [2] HILL, R. Princípios de Metalurgia Física, 1992. (author)

  12. Evaluation of the Characteristics of the Aluminum Alloy Casting Material by Heat Treatment

    International Nuclear Information System (INIS)

    Lee, Syung Yul; Park, Dong Hyun; Won, Jong Pil; Kim, Yun Hae; Lee, Myung Hoon; Moon, Kyung Man; Jeong, Jae Hyun

    2012-01-01

    Aluminum is on active metal, but it is well known that its oxide film plays a role as protective barrier which is comparatively stable in air and neutral aqueous solution. Thus, aluminum alloys have been widely applied in architectural trim, cold and hot-water storage vessels and piping etc., furthermore, the aluminum alloy of AC8A have been widely used in mold casting material of engine piston because of its properties of temperature and wear resistance. In recent years, the oil price is getting higher and higher, thus the using of low quality oil has been significantly increased in engines of ship and vehicle. Therefore it is considered that evaluation of corrosion resistance as well as wear resistance of AC8A material is also important to improve its property and prolong its lifetime. In this study, the effect of solution and tempering heat treatment to corrosion and wear resistance is investigated with electrochemical method and measurement of hardness. The hardness decreased with solution heat treatment compared to mold casting condition, but its value increased with tempering heat treatment and exhibited the highest value of hardness with tempering heat treatment temperature at 190 .deg. C for 24hrs. Furthermore, corrosion resistance increased with decreasing of the hardness, and decreased with increasing of the hardness reversely. As a result, it is suggested that the optimum heat treatment to improve both corrosion and wear resistance is tempering heat treatment temperature at 190 .deg. C for 16hrs

  13. Improvement of stress-rupture life of GTD-111 by second solution heat treatment

    International Nuclear Information System (INIS)

    Yang, Caixiong; Xu, Yulai; Zhang, Zixing; Nie, Heng; Xiao, Xueshan; Jia, Guoqing; Shen, Zhi

    2013-01-01

    Highlights: ► The second solution heat treatment promoted the solution of γ–γ′ eutectic into γ matrix. ► The volume fraction of γ′ increases significantly after adding the second solution heat treatment. ► The improved stress-rupture life is primarily due to the increased volume fraction of γ′ phase. -- Abstract: An added second solution heat treatment was conducted to investigate its effects on the microstructures and stress-rupture properties of GTD-111. The microstructures were analyzed by scanning electron microscope after each step of heat treatments. The stress-rupture life of GTD-111 dramatically increases from about 180 to 288 h at 871 °C/310 MPa after adding a second solution heat treatment. The added second solution heat treatment promoted the solution of γ–γ′ eutectic into γ matrix, and facilitated the nucleation and precipitate of the secondary γ′ particles. The distribution of γ′ phase becomes much denser, the width of γ matrix channel is also reduced, and the volume fraction of γ′ phase significantly increases from about 29.3% to 44.2%. The improved stress-rupture life is primarily due to the increased volume fraction of γ′ phase. The carbides mainly consist of MC and a small amount of M 23 C 6 , which may prevent the dislocation moving and/or grain boundary sliding, and further improve the stress-rupture properties of GTD-111.

  14. In situ post-weld heat treatment on martensitic stainless steel turbine runners using a robotic induction heating process to control temperature distribution

    Science.gov (United States)

    Boudreault, E.; Hazel, B.; Côté, J.; Godin, S.

    2014-03-01

    A new robotic heat treatment process is developed. Using this solution it is now possible to perform local heat treatment on large steel components. Crack, cavitation and erosion repairs on turbine blades and Pelton buckets are among the applications of this technique. The proof of concept is made on a 13Cr-4Ni stainless steel designated "CA6NM". This alloy is widely used in the power industry for modern system components. Given the very tight temperature tolerance (600 to 630 °C) for post-weld heat treatment on this alloy, 13Cr-4Ni stainless steel is very well suited for demonstrating the possibilities of this process. To achieve heat treatment requirements, an induction heating system is mounted on a compact manipulator named "Scompi". This robot moves a pancake coil in order to control the temperature distribution. A simulator using thermal finite element analysis is first used for path planning. A feedback loop adjusts parameters in function of environmental conditions.

  15. In situ post-weld heat treatment on martensitic stainless steel turbine runners using a robotic induction heating process to control temperature distribution

    International Nuclear Information System (INIS)

    Boudreault, E; Hazel, B; Côté, J; Godin, S

    2014-01-01

    A new robotic heat treatment process is developed. Using this solution it is now possible to perform local heat treatment on large steel components. Crack, cavitation and erosion repairs on turbine blades and Pelton buckets are among the applications of this technique. The proof of concept is made on a 13Cr-4Ni stainless steel designated C A6NM . This alloy is widely used in the power industry for modern system components. Given the very tight temperature tolerance (600 to 630 °C) for post-weld heat treatment on this alloy, 13Cr-4Ni stainless steel is very well suited for demonstrating the possibilities of this process. To achieve heat treatment requirements, an induction heating system is mounted on a compact manipulator named S compi . This robot moves a pancake coil in order to control the temperature distribution. A simulator using thermal finite element analysis is first used for path planning. A feedback loop adjusts parameters in function of environmental conditions

  16. Heat treatment of the EN AC-AlSi9Cu3(Fe alloy

    Directory of Open Access Journals (Sweden)

    J. Pezda

    2010-04-01

    Full Text Available Silumins are widely used in automotive, aviation and shipbuilding industries; as having specific gravity nearly three times lower than specific gravity of cast iron the silumins can be characterized by high mechanical properties. Additionally, they feature good casting properties, good machinability and good thermal conductivity. i.e. properties as required for machinery components operating in high temperatures and at considerable loads. Mechanical properties of the silumins can be upgraded, implementing suitably selected heat treatment. In the paper is presented an effect of modification and heat treatment processes on mechanical properties of the EN AC-AlSi9Cu3(Fe alloy. Investigated alloy has undergone typical processes of modification and refining, and next heat treatment. Temperature range of the heat treatment operations was determined on base of curves from the ATD method. Obtained results concern registered melting and solidification curves from the ATD method and strength tests. On base of the performed tests one has determined range of the heat treatment parameters which would assure obtainment of the best possible mechanical properties of the EN AC-AlSi9Cu3(Fe alloy.

  17. Effect of alkali and heat treatments for bioactivity of TiO{sub 2} nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seo young, E-mail: mast6269@nate.com [Dept. of Dental Biomaterials and Institute of Bio degradable material, Institute of Oral Bioscience and BK21 plus project, School of Dentistry, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of); Kim, Yu kyoung, E-mail: yk0830@naver.com [Dept. of Dental Biomaterials and Institute of Bio degradable material, Institute of Oral Bioscience and BK21 plus project, School of Dentistry, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of); Park, Il song, E-mail: ilsong@jbnu.ac.kr [Division of Advanced Materials Engineering, Research Center for Advanced Materials Development and Institute of Biodegradable Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Jin, Guang chun, E-mail: jingc88@126.com [Oral Medical College, Beihua University, Jilin City 132013 (China); Bae, Tae sung, E-mail: bts@jbnu.ac.kr [Dept. of Dental Biomaterials and Institute of Bio degradable material, Institute of Oral Bioscience and BK21 plus project, School of Dentistry, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of); Lee, Min ho, E-mail: mh@jbnu.ac.kr [Dept. of Dental Biomaterials and Institute of Bio degradable material, Institute of Oral Bioscience and BK21 plus project, School of Dentistry, Chonbuk National University, Jeonju, 561-756 (Korea, Republic of)

    2014-12-01

    Highlights: • TiO{sub 2} nanotubes formed via anodization were treated by alkali and heat. • The surface roughness was increased after alkali treatment (p < 0.05). • After alkali and heat treatment, the wettability was better than before treatment. • Alkali treated TiO{sub 2} nanotubes were shown higher HAp formation in SBF. • Heat treatment affected on the attachment of cells for alkali treated nanotubes. - Abstract: In this study, for improving the bioactivity of titanium used as an implant material, alkali and heat treatments were carried out after formation of the nanotubes via anodization. Nanotubes with uniform length, diameter, and thickness were formed by anodization. The alkali and heat-treated TiO{sub 2} nanotubes were covered with the complex network structure, and the Na compound was generated on the surface of the specimens. In addition, after 5 and 10 days of immersion in the SBF, the crystallized OCP and HAp phase was significantly increased on the surface of the alkali-treated TiO{sub 2} nanotubes (PNA) and alkali and heat-treated TiO{sub 2} nanotubes (PNAH) groups. Cell proliferation was decreased due to the formation of amorphous sodium titanate (Na{sub 2}TiO{sub 3}) layer on the surface of the PNA group. However, anatase and crystalline sodium titanate were formed on the surface of the PNAH group after heat treatment at 550 °C, and cell proliferation was improved. Thus, PNA group had higher HAp forming ability in the simulated body fluid. Additional heat treatment affected on enhancement of the bioactivity and the attachment of osteoblasts for PNA group.

  18. EFFECT OF HEAT TREATMENT ON SOYBEAN PROTEIN SOLUBILITY

    Directory of Open Access Journals (Sweden)

    RODICA CĂPRIŢĂ

    2007-05-01

    Full Text Available The use of soybean products in animal feeds is limited due to the presence of antinutritional factors (ANF. Proper heat processing is required to destroy ANF naturally present in raw soybeans and to remove solvent remaining from the oil extraction process. Over and under toasting of soybean causes lower nutritional value. Excessive heat treatment causes Maillard reaction which affects the availability of lysine in particular and produces changes to the chemical structure of proteins resulting in a decrease of the nutritive value. The objective of this study was to evaluate the effect of heating time on the protein solubility. The investigation of the heating time on protein solubility in soybean meal (SBM revealed a negative correlation (r = -0.9596. Since the urease index is suitable only for detecting under processed SBM, the protein solubility is an important index for monitoring SBM quality.

  19. Computerized property prediction and process planning in heat treatment of steels

    Energy Technology Data Exchange (ETDEWEB)

    Gergely, M. (Steel Advisory Centre for Industrial Technologies (SACIT), Budapest (Hungary)); Somogyi, S. (Steel Advisory Centre for Industrial Technologies (SACIT), Budapest (Hungary)); Kohlheb, R. (Steel Advisory Centre for Industrial Technologies (SACIT), Budapest (Hungary))

    1994-01-01

    Recent years have seen widespread interest in the establishment of prediction methods, based on phenomenological description and computer simulation of transformation processes during heat treatment, and in the introduction of software for technological planning. The steady development of this approach is aimed at meeting the requirement of metallurgists, design engineers dealing with material selection and dimensioning, and technologists planning heat treatment processes. Research in this field of computer simulation has been concentrated so far on two main areas of interest: . Modelling of transformation processes and the prediction of microstructures and/or properties, . Developing program packages to help solve concrete tasks such as material selection, on-line process control and monitoring, and the design of heat-treating operations. During the last two decades in the field of heat treatment, various mathematical models with different accuracy and complexity have been developed. In this paper, an attempt is made to outline some important results in computer simulation and computerized property prediction without aiming at completeness. The topic is restricted to quenched and tempered, and case-hardened steels. (orig.)

  20. Oncostatin M induces heat hypersensitivity by gp130-dependent sensitization of TRPV1 in sensory neurons

    Directory of Open Access Journals (Sweden)

    Langeslag Michiel

    2011-12-01

    Full Text Available Abstract Oncostatin M (OSM is a member of the interleukin-6 cytokine family and regulates eg. gene activation, cell survival, proliferation and differentiation. OSM binds to a receptor complex consisting of the ubiquitously expressed signal transducer gp130 and the ligand binding OSM receptor subunit, which is expressed on a specific subset of primary afferent neurons. In the present study, the effect of OSM on heat nociception was investigated in nociceptor-specific gp130 knock-out (SNS-gp130-/- and gp130 floxed (gp130fl/fl mice. Subcutaneous injection of pathophysiologically relevant concentrations of OSM into the hind-paw of C57BL6J wild type mice significantly reduced paw withdrawal latencies to heat stimulation. In contrast to gp130fl/fl mice, OSM did not induce heat hypersensitivity in vivo in SNS-gp130-/- mice. OSM applied at the receptive fields of sensory neurons in in vitro skin-nerve preparations showed that OSM significantly increased the discharge rate during a standard ramp-shaped heat stimulus. The capsaicin- and heat-sensitive ion channel TRPV1, expressed on a subpopulation of nociceptive neurons, has been shown to play an important role in inflammation-induced heat hypersensitivity. Stimulation of cultured dorsal root ganglion neurons with OSM resulted in potentiation of capsaicin induced ionic currents. In line with these recordings, mice with a null mutation of the TRPV1 gene did not show any signs of OSM-induced heat hypersensitivity in vivo. The present data suggest that OSM induces thermal hypersensitivity by directly sensitizing nociceptors via OSMR-gp130 receptor mediated potentiation of TRPV1.

  1. Transient Receptor Potential Vanilloid 1 is essential for cisplatin-induced heat hyperalgesia in mice

    Directory of Open Access Journals (Sweden)

    Carlton Susan M

    2010-03-01

    Full Text Available Abstract Background Cisplatin is primarily used for treatment of ovarian and testicular cancer. Oxaliplatin is the only effective treatment for metastatic colorectal cancer. Both are known to cause dose related, cumulative toxic effects on the peripheral nervous system and thirty to forty percent of cancer patients receiving these agents experience painful peripheral neuropathy. The mechanisms underlying painful platinum-induced neuropathy remain poorly understood. Previous studies have demonstrated important roles for TRPV1, TRPM8, and TRPA1 in inflammation and nerve injury induced pain. Results In this study, using real-time, reverse transcriptase, polymerase chain reaction (RT-PCR, we analyzed the expression of TRPV1, TRPM8, and TRPA1 induced by cisplatin or oxaliplatin in vitro and in vivo. For in vitro studies, cultured E15 rat dorsal root ganglion (DRG neurons were treated for up to 48 hours with cisplatin or oxaliplatin. For in vivo studies, trigeminal ganglia (TG were isolated from mice treated with platinum drugs for three weeks. We show that cisplatin and oxaliplatin-treated DRG neurons had significantly increased in TRPV1, TRPA1, and TRPM8 mRNA expression. TG neurons from cisplatin treated mice had significant increases in TRPV1 and TRPA1 mRNA expression while oxaliplatin strongly induced only TRPA1. Furthermore, compared to the cisplatin-treated wild-type mice, cisplatin-treated TRPV1-null mice developed mechanical allodynia but did not exhibit enhancement of noxious heat- evoked pain responses. Immunohistochemistry studies showed that cisplatin-treated mice had no change in the proportion of the TRPV1 immunopositive TG neurons. Conclusion These results indicate that TRPV1 and TRPA1 could contribute to the development of thermal hyperalgesia and mechanical allodynia following cisplatin-induced painful neuropathy but that TRPV1 has a crucial role in cisplatin-induced thermal hyperalgesia in vivo.

  2. CELLS OVEREXPRESSING HSP27 SHOW ACCELERATED RECOVERY FROM HEAT-INDUCED NUCLEAR-PROTEIN AGGREGATION

    NARCIS (Netherlands)

    KAMPINGA, HH; BRUNSTING, JF; STEGE, GJJ; KONINGS, AWT; LANDRY, J

    1994-01-01

    Protein denaturation/aggregation upon cell exposure to heat shock is a likely cause of cell death. in the nucleus, protein aggregation has often been correlated to inhibition of nuclear located processes and heat-induced cell killing. in Chinese hamster 023 cells made thermotolerant by a prior

  3. Beam-induced heat loads on the beam screens of the inner triplets for the HL-LHC

    CERN Document Server

    Skripka, Galina; CERN. Geneva. ATS Department

    2018-01-01

    The expected heat load induced on the beam screens has been evaluated for the triplet assemblies in the four experimental Insertion Regions (IRs) of the HL-LHC. The contribution from electron cloud effects has been estimated using PyECLOUD macroparticle simulations. The presence of a surface treatment for the reduction of the Secondary Electron Yield has been taken into account. The contribution from the impedance of the beam screen has been evaluated taking into account the impact of the temperature and of the magnetic field on the resistivity of the surface.

  4. Heat shock protein 70 negatively regulates the heat-shock-induced suppression of the IκB/NF-κB cascade by facilitating IκB kinase renaturation and blocking its further denaturation

    International Nuclear Information System (INIS)

    Lee, Kyoung-Hee; Lee, Choon-Taek; Kim, Young Whan; Han, Sung Koo; Shim, Young-Soo; Yoo, Chul-Gyu

    2005-01-01

    Heat shock (HS) treatment has been previously shown to suppress the IκB/nuclear factor-κB (NF-κB) cascade by denaturing, and thus inactivating IκB kinase (IKK). HS is characterized by the induction of a group of heat shock proteins (HSPs). However, their role in the HS-induced suppression of the IκB/NF-κB cascade is unclear. Adenovirus-mediated HSP70 overexpression was found not to suppress the TNF-α-induced activation of the IκB/NF-κB pathway, thus suggesting that HSP70 is unlikely to suppress this pathway. When TNF-α-induced activation of the IκB/NF-κB pathway was regained 24 h after HS, HSP70 was found to be highly up-regulated. Moreover, blocking HSP70 induction delayed TNF-α-induced IκBα degradation and the resolubilization of IKK. In addition, HSP70 associated physically with IKK, suggesting that HSP70 is involved in the recovery process via molecular chaperone effect. Adenovirus-mediated HSP70 overexpression prior to HS blocked the IκBα stabilizing effect of HS by suppressing IKK insolubilization. Moreover, the up-regulation of endogenous HSP70 by preheating, suppressed this subsequent HS-induced IKK insolubilization, and this effect was abrogated by blocking HSP70 induction. These findings indicate that HSP70 accumulates during HS and negatively regulates the HS-induced suppression of the IκB/NF-κB cascade by facilitating the renaturation of IKK and blocking its further denaturation

  5. Assessment of flow induced vibration in a sodium-sodium heat exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, V. [Fast Reactor Technology Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu (India)], E-mail: prakash@igcar.gov.in; Thirumalai, M.; Prabhakar, R.; Vaidyanathan, G. [Fast Reactor Technology Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu (India)

    2009-01-15

    The 500 MWe Prototype Fast Breeder Reactor (PFBR) is under construction at Kalpakkam. It is a liquid metal sodium cooled pool type fast reactor with all primary components located inside a sodium pool. The heat produced due to fission in the core is transported by primary sodium to the secondary sodium in a sodium to sodium Intermediate Heat Exchanger (IHX), which in turn is transferred to water in the steam generator. PFBR IHX is a shell and tube type heat exchanger with primary sodium on shell side and secondary sodium in the tube side. Since IHX is one of the critical components placed inside the radioactive primary sodium, trouble-free operation of the IHX is very much essential for power plant availability. To validate the design and the adequacy of the support system provided for the IHX, flow induced vibration (FIV) experiments were carried out in a water test loop on a 60 deg. sector model. This paper discusses the flow induced vibration measurements carried out in 60 deg. sector model of IHX, the modeling criteria, the results and conclusion.

  6. Suppression of outgassing from spindt-type cold-cathode by heat treatment

    International Nuclear Information System (INIS)

    Miyo, Yasuhiko; Ogiwara, Norio; Saidoh, Masahiro; Hayashi, Naoki; Turuta, Kouichi.

    1995-01-01

    In Spindt type cold cathode electron source (hereafter, referred to as FEA), field emission is used for extracting electrons. It was made clear that the FEA is an excellent electron source that never causes gas release by heating peripheral parts. But the gas release form the FEA was confirmed though it was slight accompanying the extraction of current. This gas release becomes a problem when pressure measurement is carried out by using the FEA in ultrahigh or extremely high vacuum. If the gas release occurs by the effect of the heat generation at the tip of an emitter accompanying the extraction of electron current, it is possible to reduce the gas release by carrying out the heat treatment of the FEA was attempted, and as the result, it was elucidated that by the heat treatment at 400degC, the gas release form the FEA was able to be suppressed. However, a new problem that the insulation between gate and emitter deteriorated and broke during the extraction of current occurred. The experimental method and the results of the reduction of gas release by heat treatment and the observation of the broken FEA with a scanning electron microscope are reported. Also the problem that in the FEA which was heat-treated at 400degC, the current has decreased from 500 μA to 100 μA in about 100 hours occurred. As to these problems, it is necessary to continue the experiment further. (K.I.)

  7. Heat treatment of large-sized welded rotors of steam turbines for atomic power stations

    Energy Technology Data Exchange (ETDEWEB)

    Kutasov, R F; Mukhina, M P; Tustanovskii, A S

    1977-01-01

    The heat treatment of a welded rotor of grade 25Kh2NMFA steel for steam turbines of nuclear power plants was considered. A following heat treatment schedule was suggested: charging the rotor in to a furnace at 100-150 deg C, heating to 200-250 deg C and holding for 12 hrs; slow heating (10 deg C/h) to 400-450 deg C and holding for 12 hrs; slow heating to 630-640 deg C and holding for 50 hrs, cooling at a rate of 5 deg C/h down to 100 deg C, holding for 20 hrs and cooling with the furnace open. The proposed heat treatment schedule of a duration of 356 hrs ensures a temperature gradient throughout the cross section and the length of the rotor of not more than +-5 deg C, least deviations of geometric dimensions and makes possible machining finish to within 0-0.02 mm. Described are the particularities of the design of a roll-out hearth electric chamber furnace, measuring 13000x5500x5000 mm and built for the purpose of carrying out said heat treatment. The power rating of the furnace is 2850 kW.

  8. Effects of Mead Wort Heat Treatment on the Mead Fermentation Process and Antioxidant Activity.

    Science.gov (United States)

    Czabaj, Sławomir; Kawa-Rygielska, Joanna; Kucharska, Alicja Z; Kliks, Jarosław

    2017-05-14

    The effects of mead wort heat treatment on the mead fermentation process and antioxidant activity were tested. The experiment was conducted with the use of two different honeys (multiflorous and honeydew) collected from the Lower Silesia region (Poland). Heat treatment was performed with the use of a traditional technique (gently boiling), the more commonly used pasteurization, and without heat treatment (control). During the experiment fermentation dynamics were monitored using high performance liquid chromatography with refractive index detection (HPLC-RID). Total antioxidant capacity (TAC) and total phenolic content (TPC) were estimated for worts and meads using UV/Vis spectrophotometric analysis. The formation of 5-hydroxymethylfurfural (HMF) was monitored by HPLC analyses. Heat treatment had a great impact on the final antioxidant capacity of meads.

  9. Development of the heat treatment system for the 40 T hybrid magnet superconducting outsert.

    Science.gov (United States)

    Chen, W G; Chen, Z M; Chen, Z Y; Huang, P C; He, P; Zhu, J W

    2011-10-01

    The heat treatment of Nb(3)Sn coil with the glass fabric insulation is one of the key and critical processes for the outsert solenoids of the 40 T hybrid magnet, which could be wound with cable-in-conduit conductors using the insulation-wind-and-react technique. The manufacturing of the large vertical type vacuum/Ar atmosphere-protection heat treatment system has been completed and recently installed in the High Magnetic Filed Laboratory, Chinese Academy of Sciences. The heat treatment system composed mainly the furnace, the purging gas supply system, the control system, the gas impurities monitoring system, and so on. At present, the regulation and testing of the heat treatment system has been successfully finished, and all of technical parameters meet or exceed specifications.

  10. Microstructure and mechanical properties of reactor pressure vessel mock-up material treated by intercritical heat treatment

    International Nuclear Information System (INIS)

    Kim, M. C.; Lee, B. S.; Hong, J. H.; Lee, H. J.; Park, S. D.; Kim, K. B.; Yoon, J. H.; Kim, J. S.; Oh, J. M.

    2003-12-01

    The mechanical properties and microstructures of base metal and weld HAZ (Heat-Affected Zone) of a Mn-Mo-Ni low alloy steels treated by intercritical heat treatment were investigated to evaluate effects of intercritical heat treatment on mechanical properties. In order to clarify the effects of intercritical heat treatment, two types of specimen were prepared by CHT(Conventional Heat Treatment) and IHT(CHT+Intercritical Heat Treatment). Tensile test, charpy impact test and vickers hardness test were carried out to evaluate the mechanical properties. It is found that impact toughness and hardness were improved by intercritical heat treatment. Mean size of precipitates and effective grain were quantitatively analysed as microstructural factors. It is found that precipitate size was decreased and shape of precipitate was spherodized by intercritical heat treatment and grain size was also decreased. So, it is thought that these microstructural changes cause the improvement of mechanical properties by intercritical heat treatment. The simulated specimen using a Gleeble thermal simulator system was used to evaluate the mechanical properties of HAZ. It is well known that IRHAZ and SRHAZ have lower toughness than base metal. However, in the case of IHT, impact toughness of IRHAZ and SRHAZ were slightly higher than that of base metal. It is obvious that this improvement of fracture toughness in IRHAZ and SRHAZ region was closely related to the microstructural changes, such as spheroidization of precipitate and decreases of precipitate size and grain size

  11. THE HEAT TREATMENT ANALYSIS OF E110 CASE HARDENING STEEL

    Directory of Open Access Journals (Sweden)

    MAJID TOLOUEI-RAD

    2016-03-01

    Full Text Available This paper investigates mechanical and microstructural behaviour of E110 case hardening steel when subjected to different heat treatment processes including quenching, normalizing and tempering. After heat treatment samples were subjected to mechanical and metallographic analysis and the properties obtained from applying different processes were analysed. The heat treatment process had certain effects on the resultant properties and microstructures obtained for E110 steel which are described in details. Quenching produced a martensitic microstructure characterized by significant increase in material’s hardness and a significant decreased in its impact energy. Annealed specimens produced a coarse pearlitic microstructure with minimal variation in hardness and impact energy. For normalized samples, fine pearlitic microstructure was identified with a moderate increase in hardness and significant reduction in impact energy. Tempering had a significant effect on quenched specimens, with a substantial rise in material ductility and reduction of hardness with increasing tempering temperature. Furthermore, Results provide additional substantiation of temper embrittlement theory for low-carbon alloys, and indicate potential occurrence of temper embrittlement for fine pearlitic microstructures.

  12. UV-Heat Treatments for the Control of Foodborne Microbial Pathogens in Chicken Broth

    Directory of Open Access Journals (Sweden)

    M. Gouma

    2015-01-01

    Full Text Available This investigation established the process criteria for using UV-C light and mild heat (UV-H treatment to inactivate 5-Log10 cycles (performance criterion of common foodborne pathogen populations, Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, and Staphylococcus aureus, when inoculated in chicken broth. To define the target microorganism and the proper UV-H treatment conditions (including UV dose, treatment time, and temperature that would achieve the stated performance criterion, mathematical equations based on Geeraerd’s model were developed for each microorganism. For the sake of comparison, inactivation equations for heat treatments were also performed on the same chicken broth and for the same microorganisms. L. monocytogenes was the most UV-H resistant microorganism at all temperatures, requiring a UV dose between 6.10 J/mL (5.6 min and 2.26 J/mL (2.09 min to achieve 5-Log10 reductions. In comparison with UV treatments at room temperatures, the combination of UV and mild heat allowed both the UV dose and treatment time to be reduced by 30% and 63% at 55°C and 60°C, respectively. Compared to heat treatments, the UV-H process reduced the heating time for 5-Log10 reductions of all the investigated microorganisms in chicken broth from 20-fold to 2-fold when the operating temperature varied from 53 to 60°C.

  13. Study of critical dependence of stable phases in Nitinol on heat treatment using electrical resistivity probe

    International Nuclear Information System (INIS)

    Uchil, J.; Mohanchandra, K.P.; Kumara, K.G.; Mahesh, K.K.

    1998-01-01

    Phase transformations in 40% cold-worked Nitinol as a function of heat treatment have been studied using electrical resistivity variation with temperature. The stabilisation of austenitic, rhombohedral and martensitic phases is shown to critically depend on the temperatures of heat treatment by the analysis of temperature dependence of electrical resistivity in heating and cooling parts of the cycle. Characteristic values of electrical resistivity of the stable phases are determined. The R-phase has been found to form continuously with increasing heat-treatment temperature starting from room temperature and to suddenly disappear beyond heat-treatment at 683 K. The observed presence or absence of R-phase is confirmed by heat capacity measurements as a function of temperature. (orig.)

  14. Modeling heat and mass transfer in the heat treatment step of yerba maté processing

    Directory of Open Access Journals (Sweden)

    J. M. Peralta

    2007-03-01

    Full Text Available The aim of this research was to estimate the leaf and twig temperature and moisture content of yerba maté branches (Ilex paraguariensis Saint Hilaire during heat treatment, carried out in a rotary kiln dryer. These variables had to be estimated (modeling the heat and mass transfer due to the difficulty of experimental measurement in the dryer. For modeling, the equipment was divided into two zones: the flame or heat treatment zone and the drying zone. The model developed fit well with the experimental data when water loss took place only in leaves. In the first zone, leaf temperature increased until it reached 135°C and then it slowly decreased to 88°C at the exit, despite the gas temperature, which varied in this zone from 460°C to 120°C. Twig temperature increased in the two zones from its inlet temperature (25°C up to 75°C. A model error of about 3% was estimated based on theoretical and experimental data on leaf moisture content.

  15. Effects of Heat-treatments on the Mechanical Strength of Coated YSZ: An Experimental Assessment

    DEFF Research Database (Denmark)

    Toftegaard, Helmuth Langmaack; Sørensen, Bent F.; Linderoth, Søren

    2009-01-01

    The mechanical strength of thin, symmetric sandwich specimens consisting of a dense yttria-stabilized zirconia (YSZ) substrate coated with a porous NiO–YSZ layer at both major faces was investigated. Specimens were loaded in uniaxial tension to failure following heat treatments at various...... temperatures. In comparison with the YSZ material, the failure strength of coated specimens was found to increase for heat treatments at 1100°C, but decreased again with further increased heat-treatment temperatures....

  16. Influence of Heat Treatment on Mercury Cavitation Resistance of Surface Hardened 316LN Stainless Steel

    Energy Technology Data Exchange (ETDEWEB)

    Pawel, Steven J [ORNL; Hsu, Julia [Massachusetts Institute of Technology (MIT)

    2010-11-01

    The cavitation-erosion resistance of carburized 316LN stainless steel was significantly degraded but not destroyed by heat treatment in the temperature range 500-800 C. The heat treatments caused rejection of some carbon from the carburized layer into an amorphous film that formed on each specimen surface. Further, the heat treatments encouraged carbide precipitation and reduced hardness within the carburized layer, but the overall change did not reduce surface hardness fully to the level of untreated material. Heat treatments as short as 10 min at 650 C substantially reduced cavitation-erosion resistance in mercury, while heat treatments at 500 and 800 C were found to be somewhat less detrimental. Overall, the results suggest that modest thermal excursions perhaps the result of a weld made at some distance to the carburized material or a brief stress relief treatment will not render the hardened layer completely ineffective but should be avoided to the greatest extent possible.

  17. Uninterrupted heat-treatment of starch raw materials

    Energy Technology Data Exchange (ETDEWEB)

    Bronshtein, D Z

    1958-01-01

    A setup is presented, with a Rekord grinder, a Khronos scale, and other equipment of Soviet manufacture, in which oats, rye, wheat, and other grains are treated at 42 to 45 degrees prior to their use as raw materials in the ethanol industry. These materials are analyzed with respect to H/sub 2/O, starch, bulk, weight, screen analysis, and the final ethanol yields/ton of such raw materials. In a three year run in plant, this heat-treatment was advantageous, as compared to the former treatment of the starch materials.

  18. Uninterrupted heat-treatment of starch raw materials

    Energy Technology Data Exchange (ETDEWEB)

    Bronshtein, D Z

    1958-01-01

    A setup is presented, with a Rekord grinder, a Khronos scale, and other equipment of Soviet manufacture, in which oats, rye, wheat, and other grains are treated at 42 to 45/sup 0/ prior to their use as raw materials in the ethanol industry. These materials are analyzed with respect to H/sub 2/O, starch, bulk weight, screen analysis, and the final ethanol yields/ton of such raw materials. In a three year run in a plant, this heat-treatment was advantageous, as compared to the former treatment of the starch materials.

  19. The effect of heat treatment on phosphorus segregation in a submerged-arc weld metal

    International Nuclear Information System (INIS)

    Beere, W.B.; Buswell, J.T.

    1999-01-01

    Intergranular fracture (IGF) has been observed in carbon-manganese steels after irradiation or high temperature exposure for prolonged periods. The effect is associated with an increase in the ductile-brittle transition temperature and has been related to phosphorus diffusion to grain boundaries. Phosphorus also diffuses thermally at the temperatures used for post-weld heat treatments such that in principle, the slightly different heat treatments given to different parts of a large vessel could lead to differing grain boundary phosphorus coverage and hence susceptibility to IGF. The effect of typical heat treatments on phosphorus coverage has been investigated using a finite difference model based on a theory that has been fitted to a wide range of constant temperature data. Regardless of previous history, the grain boundary coverage of phosphorus was predicted to depend on the final anneal and cooling rate. These differed insufficiently in the typical heat treatments to produce significant differences in segregation. It was concluded that the ductile-brittle transition temperature in submerged-arc welds would be unaffected in vessels that had seen typical post-weld heat treatments

  20. Synthesis of Mo5SiB2 based nanocomposites by mechanical alloying and subsequent heat treatment

    International Nuclear Information System (INIS)

    Abbasi, A.R.; Shamanian, M.

    2011-01-01

    Research highlights: → α-Mo-Mo 5 SiB 2 nanocomposite was produced after 20 h milling of Mo-Si-B powders. → Heat treatment of 5 h MAed powders led to the formation of boride phases. → Heat treatment of 10 h MAed powders led to the formation of Mo 5 SiB 2 phase. → By increasing heat treatment time, quantity of Mo 5 SiB 2 phase increased. → 5 h heat treatment of 20 h MAed powders led to the formation of Mo 5 SiB 2 -based composite. - Abstract: In this study, systematic investigations were conducted on the synthesis of Mo 5 SiB 2 -based alloy by mechanical alloying and subsequent heat treatment. In this regard, Mo-12.5 mol% Si-25 mol% B powder mixture was milled for different times. Then, the mechanically alloyed powders were heat treated at 1373 K for 1 h. The phase transitions and microstructural evolutions of powder particles during mechanical alloying and heat treatment were studied by X-ray diffractometry and scanning electron microscopy. The results showed that the phase evolutions during mechanical alloying and subsequent heat treatment are strongly dependent on milling time. After 10 h of milling, a Mo solid solution was formed, but, no intermetallic phases were detected at this stage. However, an α-Mo-Mo 5 SiB 2 nanocomposite was formed after 20 h of milling. After heat treatment of 5 h mechanically alloyed powders, small amounts of MoB and Mo 2 B were detected and α-Mo-MoB-Mo 2 B composite was produced. On the other hand, heat treatment of 10 h and 20 h mechanically alloyed powders led to the formation of an α-Mo-Mo 5 SiB 2 -MoSi 2 -Mo 3 Si composite. At this point, there is a critical milling time (10 h) for the formation of Mo 5 SiB 2 phase after heat treatment wherein below that time, boride phase and after that time, Mo 5 SiB 2 phase are formed. In the case of 20 h mechanically alloyed powders, by increasing heat treatment time, not only the quantity of α-Mo was reduced and the quantity of Mo 5 SiB 2 was increased, but also new boride

  1. Phenylephrine-induced elevations in arterial blood pressure are attenuated in heat-stressed humans

    Science.gov (United States)

    Cui, Jian; Wilson, Thad E.; Crandall, Craig G.

    2002-01-01

    To test the hypothesis that phenylephrine-induced elevations in blood pressure are attenuated in heat-stressed humans, blood pressure was elevated via steady-state infusion of three doses of phenylephrine HCl in 10 healthy subjects in both normothermic and heat stress conditions. Whole body heating significantly increased sublingual temperature by 0.5 degrees C, muscle sympathetic nerve activity (MSNA), heart rate, and cardiac output and decreased total peripheral vascular resistance (TPR; all P blood pressure (MAP; P > 0.05). At the highest dose of phenylephrine, the increase in MAP and TPR from predrug baselines was significantly attenuated during the heat stress [DeltaMAP 8.4 +/- 1.2 mmHg; DeltaTPR 0.96 +/- 0.85 peripheral resistance units (PRU)] compared with normothermia (DeltaMAP 15.4 +/- 1.4 mmHg, DeltaTPR 7.13 +/- 1.18 PRU; all P blood pressure, as well as the slope of the relationship between heart rate and systolic blood pressure, respectively, was similar between thermal conditions (each P > 0.05). These data suggest that phenylephrine-induced elevations in MAP are attenuated in heat-stressed humans without affecting baroreflex control of MSNA or heart rate.

  2. Effect of heat treatment upon the fatigue-crack growth behavior of Alloy 718 weldments

    International Nuclear Information System (INIS)

    James, L.A.; Mills, W.J.

    1981-05-01

    Gas-tungsten-arc weldments in Alloy 718 were studied in fatigue-crack growth test conducted at five temperatures over the range 24--649 degree C. In general, crack growth rates increased with increasing temperature, and weldments given the ''conventional'' post-weld heat-treatment generally exhibited crack growth rates that were higher than for weldments given the ''modified'' (INEL) heat-treatment. Limited testing in the as-welded condition revealed crack growth rates significantly lower than observed for the heat-treated cases, and this was attributed to residual stresses. Three different heats of filler wire were utilized, and no heat-to-heat variations were noted. 23 refs., 9 figs., 6 tabs

  3. Effect of heat treatment temperature on microstructure

    Indian Academy of Sciences (India)

    The results of electrochemical performance measurements for the HCSs as anode material for lithium ion batteries indicate that the discharge capacity of the HCSs is improved after heat treatment at 800°C compared with the as-prepared HCSs and have a maximum value of 357 mAh/g and still retains 303 mAh/g after 40 ...

  4. Accumulation of small heat shock proteins, including mitochondrial HSP22, induced by oxidative stress and adaptive response in tomato cells

    International Nuclear Information System (INIS)

    Banzet, N.; Richaud, C.; Deveaux, Y.; Kazmaier, M.; Gagnon, J.; Triantaphylides, C.

    1998-01-01

    Changes in gene expression, by application of H2O2, O2.- generating agents (methyl viologen, digitonin) and gamma irradiation to tomato suspension cultures, were investigated and compared to the well-described heat shock response. Two-dimensional gel protein mapping analyses gave the first indication that at least small heat shock proteins (smHSP) accumulated in response to application of H2O2 and gamma irradiation, but not to O2.- generating agents. While some proteins seemed to be induced specifically by each treatment, only part of the heat shock response was observed. On the basis of Northern hybridization experiments performed with four heterologous cDNA, corresponding to classes I-IV of pea smHSP, it could be concluded that significant amounts of class I and II smHSP mRNA are induced by H2O2 and by irradiation. Taken together, these results demonstrate that in plants some HSP genes are inducible by oxidative stresses, as in micro-organisms and other eukaryotic cells. HSP22, the main stress protein that accumulates following H2O2 action or gamma irradiation, was also purified. Sequence homology of amino terminal and internal sequences, and immunoreactivity with Chenopodium rubrum mitochondrial smHSP antibody, indicated that the protein belongs to the recently discovered class of plant mitochondrial smHSP. Heat shock or a mild H2O2 pretreatment was also shown to lead to plant cell protection against oxidative injury. Therefore, the synthesis of these stress proteins can be considered as an adaptive mechanism in which mitochondrial protection could be essential

  5. Numerical analysis of heat treatment of TiCN coated AA7075 aluminium alloy

    Science.gov (United States)

    Srinath, M. K.; Prasad, M. S. Ganesha

    2018-04-01

    The Numerical analysis of heat treatments of TiCN coated AA7075 aluminium alloys is presented in this paper. The Convection-Diffusion-Reaction (CDR) equation with solutions in the Streamlined-Upward Petrov-Galerkin (SUPG) method for different parameters is provided for the understanding of the process. An experimental process to improve the surface properties of AA-7075 aluminium alloy was attempted through the coatings of TiCN and subsequent heat treatments. From the experimental process, optimized temperature and time was obtained which gave the maximum surface hardness and corrosion resistance. The paper gives an understanding and use of the CDR equation for application of the process. Expression to determine convection, diffusion and reaction parameters are provided which is used to obtain the overall expression of the heat treatment process. With the substitution of the optimized temperature and time, the governing equation may be obtained. Additionally, the total energy consumed during the heat treatment process is also developed to give a mathematical formulation of the energy consumed.

  6. Effect of heat treatment on the grooving corrosion resistance of ERW pipes

    International Nuclear Information System (INIS)

    Lee, Jong Kwon; Lee, Jae Young; Lim, Soo Hyun; Park, Ji Hwan; Seo, Bo Min; Kim, Seon Hwa

    2002-01-01

    The v-sharp grooving corrosion of ERW(electrical resistance welding) steel pipes limited their wide application in the industry in spite of their high productivity and efficiency. The grooving corrosion is caused mainly by the different microstructures between the matrix and weld that is formed during the rapid heating and cooling cycle in welding. By this localized corrosion reaction of pipes, it evolves economic problems such as the early damage of industrial facilities and pipe lines of apartment, and water pollution. Even though the diminishing of sulfur content is most effective to decrease the susceptibility of grooving corrosion, it requires costly process. In this study, improvement of grooving corrosion resistance was pursuited by post weld heat treatment in the temperature range between 650 .deg. C and 950 .deg. C. Also, the effect of heat input in the welding was investigated. By employing chromnoamperometry and potentiodynamic experiment, the corrosion rate and grooving corrosion index(α) were obtained. It was found that heat treatment could improve the grooving corrosion resistance. Among them, the heat treated at 900 .deg. C and 950 .deg. C had excellent grooving corrosion resistance. The index of heat treated specimen at 900 .deg. C and 950 .deg. C were 1.0, 1.2, respectively, which are almost immune to the grooving corrosion. Potential difference after the heat treatment, between base and weld metal was decreased considerably. While the as-received one measured 61∼71 mV, that of the 900 .deg. C heat treated steel pipe measured only 10mV. The results were explained and discussed

  7. Heat-Induced Changes in Heat Shock Protein Genes Expression in Crossbred and Baladi Pregnant Cows and Their Offspring

    International Nuclear Information System (INIS)

    Khalil, W.K.B.; Nessim, M.Z.; El- Masry, K.A.

    2010-01-01

    The experiment was carried out during August (hot climate) on twelve pregnant cows of six crossbred (50% native Baladi and 50% Brown Swiss) and six native Baladi pregnant cows in the same age and the second parity during their mid-pregnancy as detected by rectal palpation. The experiment was repeated during December (mild climate) on similar twelve pregnant cows. Blood sample was obtained from each cow at the end of August (first group) and at the end of December (second group) to obtain heat shock protein genes expression (HSP72, HSP70.01, HSP70, HSP47, k Dalton and Actin) in pregnant cows under mild and hot climate to find out, which breed is more tolerant to heat stress and to estimate offspring birth weight and their growth performances during suckling period. Comparison was made between hot climate cows group and mild climate cows group to estimate heat- induced changes in both breeds in expression level of the Hsp genes and to compare with their neonate birth weight and growth performances during suckling period. The results revealed that expression level of the Hsp genes (Hsp72, Hsp70.1, Hsp70 and Hsp 47) was higher (p<0.01) in hot season compared to that of mild season. Expression level of the Hsp genes (Hsp70.1, Hsp70 and Hsp 47) was higher (p<0.05) in crossbred cows than in Baldi cows under summer hot season. This indicates that crossbred cows are less heat tolerant than Baladi cows under heat stress climate. Heat induced decrease (p<0.01) in offspring birth weight in Baladi and crossbred by 18.1% and 25%, respectively, in weaning weight by 14.61% and 23.14%, respectively and in body weight gain by 14.61% and 21.18%, respectively

  8. THE EFFECT OF HEAT TREATMENT ON THE DURABILITY OF BAMBOO Gigantochloa scortechinii

    Directory of Open Access Journals (Sweden)

    Norashikin Kamarudin

    2012-07-01

    Full Text Available Bamboo signifies as one of the fastest growing plants and it can be used for various products. In tropical countries such as Indonesia and Malaysia, bamboo is abundantly available at reasonable prices, therefore it is used for numerous purposes. However, as lignocellulosic material, bamboo is susceptible to fungal and insect attacks. Heat treatment is an option to improve bamboo's durability. The objective of this study was to improve the durability of bamboo using hot oil palm treatment. A Malaysian grown bamboo species, Buluh Semantan (Gigantochloa scortechinii, as a study material was soaked in hot oil palm for various temperatures and soaking time, before being inoculated with the basidiomycete Coriolus versicolor in an agar block test. The results demonstrated that the longer the heating time, the more improved the durability of bamboo. Altering the temperature in the palm oil treatment produced varying results. Bamboo blocks that heated in hot oil palm at 100°C for 60 minutes shows considerably less weight eduction that indicates less fungal attack. Overall, the higher the temperature, the better the durability of bamboo. Please indicates what the meaning of heat treatment in this experiment, it is not clear.

  9. Role of wild-type p53 in apoptotic and non-apoptotic cell death induced by X-irradiation and heat treatment in p53-mutated mouse M10 cells

    International Nuclear Information System (INIS)

    Ito, Atsushi; Nakano, Hisako; Shinohara, Kunio

    2010-01-01

    The sensitizing effects of wild-type p53 on X-ray-induced cell death and on heat-induced apoptosis in M10, a radiosensitive and Trp53 (mouse p53 gene)-mutated lymphoma cell line which dies through necrosis by X-irradiation, were investigated using three M10 derived transfectants with wild-type TP53 (human p53 gene). Cell death was determined by colony formation and/or dye exclusion test, and apoptosis was detected as the changes in nuclear morphology by Giemsa staining. Expression of wild-type p53 protein increased radiosensitivity of cell death as determined by both clonogenic and dye exclusion assays. This increase in radiosensitivity was attributable largely to apoptosis induction in addition to a small enhancement of necrosis. Interestingly neither pathway to cell death was accompanied by caspase-3 activation. On the other hand, heat-induced caspase-3 dependent apoptotic cell death without transfection was further increased by the transfection of wild-type p53. In conclusion, the introduction of wild-type p53 enhanced apoptotic cell death by X-rays or heat via different mechanisms that do or do not activate caspase-3, respectively. In addition, p53 also enhanced the X-ray-induced necrosis in M10 cells. (author)

  10. Effect of Heat Treatment on Morphology of Fe-Rich Intermetallics in Hypereutectic Al-Si-Cu-Ni Alloy with 1.26 pct Fe

    Science.gov (United States)

    Sha, Meng; Wu, Shusen; Wan, Li; Lü, Shulin

    2013-12-01

    Cobalt is generally considered as the element that can neutralize the negative effects of iron in Al alloys, such as inducing fracture and failure for stress concentration. Nevertheless, Fe-rich intermetallics would be inclined to form coarse plate-like δ-Al4(Fe, Co, Ni)Si2 particles when the content of Fe was high, which could also cause inferior mechanical properties. The dissolution and transformation of δ-Al4(Fe, Co, Ni)Si2 phase in solution heat-treated samples of Al-20Si-1.85Cu-1.05Ni-1.26Fe-1.35Co alloy were studied using optical microscopy, image analysis, and scanning electron microscopy. The effects of solution heat treatment time ranging from 0 to 9 hours at 783.15 K (510 °C) on mechanical properties were also investigated. The coarse plate-like δ-Al4(Fe, Co, Ni)Si2 particles varied slowly through concurrent dissolution along widths and at the plate tips as solution treatment time increased, which could be explained from diffusion-induced grain boundary migration. Solution heat treatment also has an important influence on mechanical properties. The maximum ultimate tensile strength and yield strength after T6 treatment were 258 and 132 MPa, respectively, while the maximum hardness was 131 HB. Compared with those of the samples in the as-cast state, they increased by 53, 42, and 28 pct, respectively. Moreover, δ-Al4(Fe, Co, Ni)Si2 phase, which appears as a coarse plate-like particle in two dimensions, is actually a cuboid in three dimensions. The length of this cuboid is close to the width, while the height is much smaller.

  11. Reactions of lactose during heat treatment of milk : a quantitative study

    NARCIS (Netherlands)

    Berg, H.E.

    1993-01-01

    The kinetics of the chemical reactions of lactose during heat treatment of milk were studied. Skim milk and model solutions resembling milk were heated. Reaction products were determined and the influence of varying lactose, casein and fat concentration on the formation of these products

  12. Investigation of heat treatment conditions of structural material for blanket fabrication process

    International Nuclear Information System (INIS)

    Hirose, Takanori; Suzuki, Satoshi; Akiba, Masato; Shiba, Kiyoyuki; Sawai, Tomotsugu; Jitsukawa, Shiro

    2004-01-01

    This paper presents recent results of thermal hysteresis effects on ceramic breeder blanket structural material. Reduced activation ferritic/martensitic (RAF) steel is the leading candidates for the first wall structural materials of breeding blankets. RAF steel demonstrates superior resistance to high dose neutron irradiation, because the steel has tempered martensite structure which contains the number of sink site for radiation defects. This microstructure obtained by two-step heat treatment, first is normalizing at temperature above 1200 K and the second is tempering at temperature below 1100 K. Recent study revealed the thermal hysteresis has significant impacts on the post-irradiation mechanical properties. The breeding blanket has complicated structure, which consists of tungsten armor and thin first wall with cooling pipe. The blanket fabrication requires some high temperature joining processes. Especially hot isostatic pressing (HIP) is examined as a near-net-shape fabrication process for this structure. The process consists of heating above 1300 K and isostatic pressing at the pressure above 150 MPa followed by tempering. Moreover ceramics pebbles are packed into blanket module and the module is to be seamed by welding followed by post weld heat treatment in the final assemble process. Therefore the final microstructural features of RAFs strongly depend on the blanket fabrication process. The objective of this work is to evaluate the effects of thermal hysteresis corresponding to blanket fabrication process on RAFs microstructure in order to establish appropriate blanket fabrication process. Japanese RAFs F82H (Fe-0.1C-8Cr-2W-0.2V-0.05Ta) was investigated by metallurgical method after isochronal heat treatment up to 1473 K simulating high temperature bonding process. Although F82H showed significant grain growth after conventional solid HIP conditions (1313 K x 2 hr.), this coarse grained microstructure was refined by the post HIP normalizing at

  13. Heating patterns during cancer heat therapy as a function of blood flow

    International Nuclear Information System (INIS)

    Mendecki, J.; Friedenthal, E.; Botstein, C.; Sterzer, F.; Paglione, R.W.

    1984-01-01

    Heating patterns as a function of regional blood flow were evaluated in healthy tissues with different vascular characteristics as well as in a variety of tumors submitted to microwave and RF-induced hyperthermia. Generally, faster heating and slower cooling was demonstrated for tumors. Definite correlation was found between the power needed to heat given tissue volume to a specific temperature and the ability of this tissue to dissipate heat via vascular flow. The measurements show that during the early phase of heating of tumors temperature rises slowly up to about 40 0 C. indicating good heat exchanges but that at this level rapid increase of temperature occurs for relatively small increments of power input. It is suggested that blood flow in malignant tissue remains competent and responsive to low grade heating, but that at higher temperature levels, in contrast to normal tissue, tumor blood flow rapidly decreases indicating compromised vascular system. Implication for treatment protocols are discussed

  14. Identification of a cytotoxic molecule in heat-modified citrus pectin.

    Science.gov (United States)

    Leclere, Lionel; Fransolet, Maude; Cambier, Pierre; El Bkassiny, Sandy; Tikad, Abdellatif; Dieu, Marc; Vincent, Stéphane P; Van Cutsem, Pierre; Michiels, Carine

    2016-02-10

    Modified forms of citrus pectin possess anticancer properties. However, their mechanism of action and the structural features involved remain unclear. Here, we showed that citrus pectin modified by heat treatment displayed cytotoxic effects in cancer cells. A fractionation approach was used aiming to identify active molecules. Dialysis and ethanol precipitation followed by HPLC analysis evidenced that most of the activity was related to molecules with molecular weight corresponding to low degree of polymerization oligogalacturonic acid. Heat-treatment of galacturonic acid also generated cytotoxic molecules. Furthermore, heat-modified galacturonic acid and heat-fragmented pectin contained the same molecule that induced cell death when isolated by HPLC separation. Mass spectrometry analyses revealed that 4,5-dihydroxy-2-cyclopenten-1-one was one cytotoxic molecule present in heat-treated pectin. Finally, we synthesized the enantiopure (4R,5R)-4,5-dihydroxy-2-cyclopenten-1-one and demonstrated that this molecule was cytotoxic and induced a similar pattern of apoptotic-like features than heat-modified pectin. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. THE EFFECTS OF INTERCRITICAL HEAT TREATMENTS ON THE ...

    African Journals Online (AJOL)

    Effect of intercritical heat treatment on 0.14wt%C 0.56wt%Mn 0.13wt%Si struc- ... Table 1: Chemical composition of the steel used (wt. %) with its critical temperature (calculated). C. Mn. Si. Ni. S ... primary austenitic grain size hardening and.

  16. Effect of Cold Drawing and Heat Treatment on the Microstructure of Invar36 Alloy Wire

    International Nuclear Information System (INIS)

    Han, Seung Youb; Jang, Seon Ah; Eun, Hee-Chul; Choi, Jung-Hoon; Lee, Ki Rak; Park, Hwan Seo; Ahn, Do-Hee; Kim, Soo Young; Kim, Jea Youl; Shin, Sang Yong

    2016-01-01

    In this study, the effect of cold drawing and heat treatment on the microstructure of Invar36 alloy wire was investigated. Invar36 alloy wire is used as a transmission line core material, and is required to have high strength. The diameter of the Invar36 alloy wire specimens were reduced from 16 mm to 4.3 mm after three cold drawing and two heat treatment processes, thereby increasing tensile strength. Specimens were taken after each of the cold drawing and heat treatment processes, and their microstructure and tensile properties were analyzed. The Invar36 alloy wire had a γ-(Fe, Ni) phase matrix before the cold drawing and heat treatment processes. After the cold drawing processes, {220} and {200} textures were mainly achieved. After the heat treatment processes, a {200} recrystallization γ-(Fe, Ni) phase was formed with fine carbides. The recrystallization γ-(Fe, Ni) phase grains had low dislocation density, so they probably accommodated a large amount of deformation during the cold drawing processes.

  17. Effect of Cold Drawing and Heat Treatment on the Microstructure of Invar36 Alloy Wire

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Youb; Jang, Seon Ah; Eun, Hee-Chul; Choi, Jung-Hoon; Lee, Ki Rak; Park, Hwan Seo; Ahn, Do-Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Soo Young; Kim, Jea Youl [RandD Center, KOS Ltd., Yangsan (Korea, Republic of); Shin, Sang Yong [University of Ulsan, Ulsan (Korea, Republic of)

    2016-10-15

    In this study, the effect of cold drawing and heat treatment on the microstructure of Invar36 alloy wire was investigated. Invar36 alloy wire is used as a transmission line core material, and is required to have high strength. The diameter of the Invar36 alloy wire specimens were reduced from 16 mm to 4.3 mm after three cold drawing and two heat treatment processes, thereby increasing tensile strength. Specimens were taken after each of the cold drawing and heat treatment processes, and their microstructure and tensile properties were analyzed. The Invar36 alloy wire had a γ-(Fe, Ni) phase matrix before the cold drawing and heat treatment processes. After the cold drawing processes, {220} and {200} textures were mainly achieved. After the heat treatment processes, a {200} recrystallization γ-(Fe, Ni) phase was formed with fine carbides. The recrystallization γ-(Fe, Ni) phase grains had low dislocation density, so they probably accommodated a large amount of deformation during the cold drawing processes.

  18. Heterogeneously Nd3+ doped single nanoparticles for NIR-induced heat conversion, luminescence, and thermometry.

    Science.gov (United States)

    Marciniak, Lukasz; Pilch, Aleksandra; Arabasz, Sebastian; Jin, Dayong; Bednarkiewicz, Artur

    2017-06-22

    The current frontier in nanomaterials engineering is to intentionally design and fabricate heterogeneous nanoparticles with desirable morphology and composition, and to integrate multiple functionalities through highly controlled epitaxial growth. Here we show that heterogeneous doping of Nd 3+ ions following a core-shell design already allows three optical functions, namely efficient (η > 72%) light-to-heat conversion, bright NIR emission, and sensitive (S R > 0.1% K -1 ) localized temperature quantification, to be built within a single ca. 25 nm nanoparticle. Importantly, all these optical functions operate within the transparent biological window of the NIR spectral region (λ exc ∼ 800 nm, λ emi ∼ 860 nm), in which light scattering and absorption by tissues and water are minimal. We find NaNdF 4 as a core is efficient in absorbing and converting 808 nm light to heat, while NaYF 4 :1%Nd 3+ as a shell is a temperature sensor based on the ratio-metric luminescence reading but an intermediate inert spacer shell, e.g. NaYF 4 , is necessary to insulate the heat convertor and thermometer by preventing the possible Nd-Nd energy relaxation. Moreover, we notice that while temperature sensitivity and luminescence intensity are optically stable, increased excitation intensity to generate heat above room temperature may saturate the sensing capacity of temperature feedback. We therefore propose a dual beam photoexcitation scheme as a solution for possible light-induced hyperthermia treatment.

  19. Effect of grinding and heat treatment on the mechanical behavior of zirconia ceramic

    Directory of Open Access Journals (Sweden)

    Gabriela Freitas RAMOS

    2016-01-01

    Full Text Available Abstract The present study investigated the effect of grinding on roughness, flexural strength, and reliability of a zirconia ceramic before and after heat treatment. Seven groups were tested (n = 15: a control group (labeled CG, untreated, and six groups of samples ground with diamond discs, simulating diamond burs, with grits of 200 µm (G80; 160 µm (G120, and 25 µm (G600, either untreated or heat-treated at 1200°C for 2 h (labeled A. Yttria tetragonal zirconia polycrystal discs were manufactured, ground, and submitted to roughness and crystalline phase analyses before the biaxial flexural strength test. There was no correlation between roughness (Ra and Rz and flexural strength. The reliability of the materials was not affected by grinding or heat treatment, but the characteristic strength was higher after abrasion with diamond discs, irrespective of grit size. The X-ray diffraction data showed that grinding leads to a higher monoclinic (m phase content, whereas heat treatment produces reverse transformation, leading to a fraction of m-phase in ground samples similar to that observed in the control group. However, after heat treatment, only the G80A samples presented strength similar to that of the control group, while the other groups showed higher strength values. When zirconia pieces must be adjusted for clinical use, a smoother surface can be obtained by employing finer-grit diamond burs. Moreover, when the amount of monoclinic phase is related to the degradation of zirconia, the laboratory heat treatment of ground pieces is indicated for the reverse transformation of zirconia crystals.

  20. Effect of Pressure and Heat Treatments on the Compressive Strength of Reactive Powder Concrete

    Directory of Open Access Journals (Sweden)

    Helmi Masdar

    2018-01-01

    Full Text Available This paper presents the corresponding compressive strength of RPC with variable pressure combined with heating rate, heating duration, and starting time of heating. The treatments applied were 8 MPa static pressure on fresh RPC prims and heat curing at 240 °C in an oven. The compressive strength test was conducted at 7-d and 28-d. The images of RPC morphology were captured on the surface of a fractured specimen using Scanning Electron Microscopy in Secondary Electron detector mode to describe pore filing mechanism after treatments. The results show that a heating rate at 50 °C/hr resulted in the highest compressive strength about 40 % more than those at 10 or 100 °C/hr. A heating duration of 48 hours led to the maximum compressive strength. Heat curing applied 2 days after casting resulted in the maximum compressive. Heat curing had a signicant effect on the compresssive strength due to the acceleration of both reactions (hydration and pozzolanic and the degree of transformation from tobermorite to xonotlite. It is concluded that the optimum condition of treatments is both pressure and heat curing at 2-day after casting with a rate of 50 °C/hr for 48 hours.

  1. Effect of heat treatment regime on structural lamination in ferritic-austenitic steels

    International Nuclear Information System (INIS)

    Sizov, R.A.; Zakharova, M.I.; Novikov, I.I.; Bannykh, O.A.

    1983-01-01

    The effect of preliminary thermal treatment on lamination and viscosity of EhP-53 and KO-3 steels after durable aging at the temperature of 350 is studied. It is shown that preliminary heat treatment considerably affects lamination processes in the result of aging of 0Kh18G8N2T steel. The lowest rate of lamination and higher impact strength after aging at 350 deg C for 4500 hours corresponds to the following heat treatment: 10 hour aging at 650 deg C with cooling in the air, then quenching in water from 950 deg C after aging for 30 min and the following tempering (650 deg C, 5 hours). Unlike the 0Kh18G8N2T steel, lamination parameters of steel 0Kh22N6T practically do not change after the application of heat treatment. Nevertherless, taking into account results of impact strength, it is advisable to have thermal treatment according to the regime: quenching in water at 950 deg C after aging for 30 min

  2. heat-induced biological changes as heat tolerance indices related to growth performance in buffaloes

    International Nuclear Information System (INIS)

    Kaldes, M.Z.N.

    2004-01-01

    the main objective of this study was to predict new heat tolerance indices related to hot summer growth performance, depending on heat - induced changes in some physiological and biochemical parameters of young water buffalo calves. the present study was carried out on 8 egyptian male buffalo calves of 6 months old and 106.8 kg mean body weight (B W), and on the same animals of 12 months old and 179.5 kg mean B W. the animals were maintained in a climatic chamber of the egyptian atomic energy authority. the animals were maintained in metabolic cages inside a climatic chamber for 3 weeks under mild climate (20-24 c and 50-60% Rh, equivalent to 62-72 THI) for 6 hours daily as adjustment period,followed by 5 and 7 days in the 6- and 12-month old calves, respectively at the same climatic conditions as a control period.this was followed by 6 hours of acute heat exposure period (33-43 c and 40-60% Rh, equivalent to 85-93 Thi), then by chronic heat exposure period of the same climatic conditions for 5 and 7 days in the 6- and 12- month old calves, respectively.Rectal temperature (RT) and respiration rate (RR) were estimated daily, whereas BW was estimated at the beginning and the end of each exposure period

  3. Effect of Heat Treatment on the Lycopene Content of Tomato Puree ...

    African Journals Online (AJOL)

    Effect of Heat Treatment on the Lycopene Content of Tomato Puree. MI Mohammed, DI Malami. Abstract. Lycopene is a powerful antioxidant. Epidemiological studies have associated its consumption with numerous health benefits. In this study the effects of heating on lycopene were investigated by exposing tomato ...

  4. Transition of Emission Colours as a Consequence of Heat-Treatment of Carbon Coated Ce3+-Doped YAG Phosphors

    Directory of Open Access Journals (Sweden)

    Liang-Jun Yin

    2017-10-01

    Full Text Available To modify the luminescence properties of Ce3+-doped Y3Al5O12 (YAG phosphors, they have been coated with a carbon layer by chemical vapor deposition and subsequently heat-treated at high temperature under N2 atmosphere. Luminescence of the carbon coated YAG:Ce3+ phosphors has been investigated as a function of heat-treatment at 1500 and 1650 °C. The 540 nm emission intensity of C@YAG:Ce3+ is the highest when heated at 1650 °C, while a blue emission at 400–420 nm is observed when heated at 1500 °C but not at 1650 °C. It is verified by X-ray diffraction (XRD that the intriguing luminescence changes are induced by the formation of new phases in C@YAG:Ce3+-1500 °C, which disappear in C@YAG:Ce3+-1650 °C. In order to understand the mechanisms responsible for the enhancement of YAG:Ce3+ emission and the presence of the blue emission observed for C@YAG:Ce3+-1500 °C, the samples have been investigated by a combination of several electron microscopy techniques, such as HRTEM, SEM-CL, and SEM-EDS. This local and cross-sectional analysis clearly reveals a gradual transformation of phase and morphology in heated C@YAG:Ce3+ phosphors, which is related to a reaction between C and YAG:Ce3+ in N2 atmosphere. Through reaction between the carbon layer and YAG host materials, the emission colour of the phosphors can be modified from yellow, white, and then back to yellow under UV excitation as a function of heat-treatment in N2 atmosphere.

  5. Transition of Emission Colours as a Consequence of Heat-Treatment of Carbon Coated Ce3+-Doped YAG Phosphors.

    Science.gov (United States)

    Yin, Liang-Jun; Dierre, Benjamin; Sekiguchi, Takashi; van Ommen, J Ruud; Hintzen, Hubertus T Bert; Cho, Yujin

    2017-10-16

    To modify the luminescence properties of Ce 3+ -doped Y₃Al₅O 12 (YAG) phosphors, they have been coated with a carbon layer by chemical vapor deposition and subsequently heat-treated at high temperature under N₂ atmosphere. Luminescence of the carbon coated YAG:Ce 3+ phosphors has been investigated as a function of heat-treatment at 1500 and 1650 °C. The 540 nm emission intensity of C@YAG:Ce 3+ is the highest when heated at 1650 °C, while a blue emission at 400-420 nm is observed when heated at 1500 °C but not at 1650 °C. It is verified by X-ray diffraction (XRD) that the intriguing luminescence changes are induced by the formation of new phases in C@YAG:Ce 3+ -1500 °C, which disappear in C@YAG:Ce 3+ -1650 °C. In order to understand the mechanisms responsible for the enhancement of YAG:Ce 3+ emission and the presence of the blue emission observed for C@YAG:Ce 3+ -1500 °C, the samples have been investigated by a combination of several electron microscopy techniques, such as HRTEM, SEM-CL, and SEM-EDS. This local and cross-sectional analysis clearly reveals a gradual transformation of phase and morphology in heated C@YAG:Ce 3+ phosphors, which is related to a reaction between C and YAG:Ce 3+ in N₂ atmosphere. Through reaction between the carbon layer and YAG host materials, the emission colour of the phosphors can be modified from yellow, white, and then back to yellow under UV excitation as a function of heat-treatment in N₂ atmosphere.

  6. Effect of heat treatment duration on tribological behavior of electroless Ni-(high)P coatings

    Science.gov (United States)

    Biswas, A.; Das, S. K.; Sahoo, P.

    2016-09-01

    Electroless nickel coating occurs through an autocatalytic chemical reaction and without the aid of electricity. From tribological perspective, it is recommended due to its high hardness, wear resistance, lubricity and corrosion resistance properties. In this paper electroless Ni-P coatings with high phosphorous weight percentages are developed on mild steel (AISI 1040) substrates. The coatings are subjected to heat treatment at 300°C and 500°C for time durations up to 4 hours. The effect of heat treatment duration on the hardness as well as tribological properties is discussed in detail. Hardness is measured in a micro hardness tester while the tribological tests are carried out on a pin-on-disc tribotester. Wear is reported in the form of wear rates of the sample subjected to the test. As expected, heat treatment of electroless Ni-P coating results in enhancement in its hardness which in turn increases its wear resistance. The present study also finds that duration of heat treatment has quite an effect on the properties of the coating. Increase in heat treatment time in general results in increase in the hardness of the coating. Coefficient of friction is also found to be lesser for the samples heat treated for longer durations (4 hour). However, in case of wear, similar trend is not observed. Instead samples heat treated for 2 to 3 hour display better wear resistance compared to the same heat treated for 4 hour duration. The microstructure of the coating is also carried out to ensure about its proper development. From scanning electron microscopy (SEM), the coating is found to possess the conventional nodular structure while energy dispersive X-ray analysis (EDX) shows that the phosphorous content in the coating to be greater than 9%. This means that the current coating belongs to the high phosphorous category. From X-ray diffraction analysis (XRD), it is found that coating is amorphous in as-deposited condition but transforms into a crystalline structure with

  7. Flexible and stable heat energy recovery from municipal wastewater treatment plants using a fixed-inverter hybrid heat pump system

    International Nuclear Information System (INIS)

    Chae, Kyu-Jung; Ren, Xianghao

    2016-01-01

    Highlights: • Specially designed fixed-inverter hybrid heat pump system was developed. • Hybrid operation performed better at part loads than single inverter operation. • The applied heat pump can work stably over a wide range of heat load variations. • Heat energy potential of treated effluent was better than influent. • The heat pump’s COP from the field test was 4.06 for heating and 3.64 for cooling. - Abstract: Among many options to improve energy self-sufficiency in sewage treatment plants, heat extraction using a heat pump holds great promise, since wastewater contains considerable amounts of thermal energy. The actual heat energy demand at municipal wastewater treatment plants (WWTPs) varies widely with time; however, the heat pumps typically installed in WWTPs are of the on/off controlled fixed-speed type, thus mostly run intermittently at severe part-load conditions with poor efficiency. To solve this mismatch, a specially designed, fixed-inverter hybrid heat pump system incorporating a fixed-speed compressor and an inverter-driven, variable-speed compressor was developed and tested in a real WWTP. In this hybrid configuration, to improve load response and energy efficiency, the base-heat load was covered by the fixed-speed compressor consuming relatively less energy than the variable-speed type at nominal power, and the remaining varying load was handled by the inverter compressor which exhibits a high load-match function while consuming relatively greater energy. The heat pump system developed reliably extracted heat from the treated effluent as a heat source for heating and cooling purposes throughout the year, and actively responded to the load changes with a high measured coefficient of performance (COP) of 4.06 for heating and 3.64 for cooling. Moreover, this hybrid operation yielded a performance up to 15.04% better on part loads than the single inverter operation, suggesting its effectiveness for improving annual energy saving when

  8. Effect of heat treatment on antimycotic activity of Sahara honey

    Directory of Open Access Journals (Sweden)

    Moussa Ahmed

    2014-11-01

    Full Text Available Objective: To evaluate the influence of the temperature on honey colour, polyphenol contents and antimycotic capacity and to evaluate the correlation between these parameters. Methods: Sahara honey were heated up to 25, 50, 75 and 100 °C for 15, 30 and 60 min, and their colour intensity, polyphenol contents and antimycotic capacity. The Folin-Ciocalteu test was used to determine the total polyphenol contents (TPC. The antimycotic activity was evaluated both by agar diffusion method and micro wells dilution method against the Candida albicans (C. albicans and Candida glabrata (C. glabrata. Results: Initial values for TPC in Sahara honey ranged from 0.55 to 1.14 mg of gallic acid per kg of honey, with the average value of 0.78 mg of gallic acid per kg of honey. The TPC values after heat-treatment were 0.54 to 1.54 with the average value of 1.49 mg. The minimal inhibitory concentrations before heat-treatment of Sahara honey against C. albicans and C. glabrata ranged from 3.06%-12.5% and 50% respectively. After heat-treatment the minimal inhibitory concentrations between 12.5% and 50% for C. albicans and C. glabrata, respectively. The diameters of inhibition zones of Sahara honey with 50% concentration varied from (12.67-15.00 mm by C. albicans to (14.33-15.67 mm by C. glabrata. The diameters of inhibition zones after heat-treatment at 25 and 50 °C for 15.30 and 60 min ranged from (2.00-18.67 mm by C. albicans to (8.00-16.67 mm by C. glabrata. Statistically significant relations between the TPC and the colour intensity of Sahara honey (r=0.99, P<0.05. Furthermore, the results showed that the TPC and colour is not correlated with the antimycotic capacity. Conclusions: To our knowledge this is the first report on the antimycotic capacity of Sahara honey.

  9. Caffeine Induces the Stress Response and Up-Regulates Heat Shock Proteins in Caenorhabditis elegans.

    Science.gov (United States)

    Al-Amin, Mohammad; Kawasaki, Ichiro; Gong, Joomi; Shim, Yhong-Hee

    2016-02-01

    Caffeine has both positive and negative effects on physiological functions in a dose-dependent manner. C. elegans has been used as an animal model to investigate the effects of caffeine on development. Caffeine treatment at a high dose (30 mM) showed detrimental effects and caused early larval arrest. We performed a comparative proteomic analysis to investigate the mode of action of high-dose caffeine treatment in C. elegans and found that the stress response proteins, heat shock protein (HSP)-4 (endoplasmic reticulum [ER] chaperone), HSP-6 (mitochondrial chaperone), and HSP-16 (cytosolic chaperone), were induced and their expression was regulated at the transcriptional level. These findings suggest that high-dose caffeine intake causes a strong stress response and activates all three stress-response pathways in the worms, including the ER-, mitochondrial-, and cytosolic pathways. RNA interference of each hsp gene or in triple combination retarded growth. In addition, caffeine treatment stimulated a food-avoidance behavior (aversion phenotype), which was enhanced by RNAi depletion of the hsp-4 gene. Therefore, up-regulation of hsp genes after caffeine treatment appeared to be the major responses to alleviate stress and protect against developmental arrest.

  10. Heat-stress and light-stress induce different cellular pathologies in the symbiotic dinoflagellate during coral bleaching.

    Science.gov (United States)

    Downs, C A; McDougall, Kathleen E; Woodley, Cheryl M; Fauth, John E; Richmond, Robert H; Kushmaro, Ariel; Gibb, Stuart W; Loya, Yossi; Ostrander, Gary K; Kramarsky-Winter, Esti

    2013-01-01

    Coral bleaching is a significant contributor to the worldwide degradation of coral reefs and is indicative of the termination of symbiosis between the coral host and its symbiotic algae (dinoflagellate; Symbiodinium sp. complex), usually by expulsion or xenophagy (symbiophagy) of its dinoflagellates. Herein, we provide evidence that during the earliest stages of environmentally induced bleaching, heat stress and light stress generate distinctly different pathomorphological changes in the chloroplasts, while a combined heat- and light-stress exposure induces both pathomorphologies; suggesting that these stressors act on the dinoflagellate by different mechanisms. Within the first 48 hours of a heat stress (32°C) under low-light conditions, heat stress induced decomposition of thylakoid structures before observation of extensive oxidative damage; thus it is the disorganization of the thylakoids that creates the conditions allowing photo-oxidative-stress. Conversely, during the first 48 hours of a light stress (2007 µmoles m(-2) s(-1) PAR) at 25°C, condensation or fusion of multiple thylakoid lamellae occurred coincidently with levels of oxidative damage products, implying that photo-oxidative stress causes the structural membrane damage within the chloroplasts. Exposure to combined heat- and light-stresses induced both pathomorphologies, confirming that these stressors acted on the dinoflagellate via different mechanisms. Within 72 hours of exposure to heat and/or light stresses, homeostatic processes (e.g., heat-shock protein and anti-oxidant enzyme response) were evident in the remaining intact dinoflagellates, regardless of the initiating stressor. Understanding the sequence of events during bleaching when triggered by different environmental stressors is important for predicting both severity and consequences of coral bleaching.

  11. Heat-stress and light-stress induce different cellular pathologies in the symbiotic dinoflagellate during coral bleaching.

    Directory of Open Access Journals (Sweden)

    C A Downs

    Full Text Available Coral bleaching is a significant contributor to the worldwide degradation of coral reefs and is indicative of the termination of symbiosis between the coral host and its symbiotic algae (dinoflagellate; Symbiodinium sp. complex, usually by expulsion or xenophagy (symbiophagy of its dinoflagellates. Herein, we provide evidence that during the earliest stages of environmentally induced bleaching, heat stress and light stress generate distinctly different pathomorphological changes in the chloroplasts, while a combined heat- and light-stress exposure induces both pathomorphologies; suggesting that these stressors act on the dinoflagellate by different mechanisms. Within the first 48 hours of a heat stress (32°C under low-light conditions, heat stress induced decomposition of thylakoid structures before observation of extensive oxidative damage; thus it is the disorganization of the thylakoids that creates the conditions allowing photo-oxidative-stress. Conversely, during the first 48 hours of a light stress (2007 µmoles m(-2 s(-1 PAR at 25°C, condensation or fusion of multiple thylakoid lamellae occurred coincidently with levels of oxidative damage products, implying that photo-oxidative stress causes the structural membrane damage within the chloroplasts. Exposure to combined heat- and light-stresses induced both pathomorphologies, confirming that these stressors acted on the dinoflagellate via different mechanisms. Within 72 hours of exposure to heat and/or light stresses, homeostatic processes (e.g., heat-shock protein and anti-oxidant enzyme response were evident in the remaining intact dinoflagellates, regardless of the initiating stressor. Understanding the sequence of events during bleaching when triggered by different environmental stressors is important for predicting both severity and consequences of coral bleaching.

  12. Effect of heat treatment duration on phase separation of sodium borosilicate glass, containing copper

    International Nuclear Information System (INIS)

    Shejnina, T.G.; Gutner, S.Kh.; Anan'in, N.I.

    1989-01-01

    The effect of heat treatment duration on phase separation of sodium borosilicate (SBS) glass, containing copper is studied. It is stated that phase separation close to equilibrium one is attained under 12 hours of heat treatment of SBS glass containing copper

  13. Chemotherapy and Radiofrequency-Induced Mild Hyperthermia Combined Treatment of Orthotopic Pancreatic Ductal Adenocarcinoma Xenografts.

    Science.gov (United States)

    Krzykawska-Serda, Martyna; Agha, Mahdi S; Ho, Jason Chak-Shing; Ware, Matthew J; Law, Justin J; Newton, Jared M; Nguyen, Lam; Curley, Steven A; Corr, Stuart J

    2018-04-02

    Patients with pancreatic ductal adenocarcinomas (PDAC) have one of the poorest survival rates of all cancers. The main reason for this is related to the unique tumor stroma and poor vascularization of PDAC. As a consequence, chemotherapeutic drugs, such as nab-paclitaxel and gemcitabine, cannot efficiently penetrate into the tumor tissue. Non-invasive radiofrequency (RF) mild hyperthermia treatment was proposed as a synergistic therapy to enhance drug uptake into the tumor by increasing tumor vascular inflow and perfusion, thus, increasing the effect of chemotherapy. RF-induced hyperthermia is a safer and non-invasive technique of tumor heating compared to conventional contact heating procedures. In this study, we investigated the short- and long-term effects (~20 days and 65 days, respectively) of combination chemotherapy and RF hyperthermia in an orthotopic PDAC model in mice. The benefit of nab-paclitaxel and gemcitabine treatment was confirmed in mice; however, the effect of treatment was statistically insignificant in comparison to saline treated mice during long-term observation. The benefit of RF was minimal in the short-term and completely insignificant during long-term observation. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  14. The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Mamum, Md Abdullah A. [Old Dominion Univ., Norfolk, VA (United States); Elmustafa, Abdelmageed A, [Old Dominion Univ., Norfolk, VA (United States); Stutzman, Marcy L. [JLAB, Newport News, VA (United States); Adderley, Philip A. [JLAB, Newport News, VA (United States); Poelker, Matthew [JLAB, Newport News, VA (United States)

    2014-03-01

    The outgassing rates of four nominally identical 304L stainless steel vacuum chambers were measured to determine the effect of chamber coatings and heat treatments. One chamber was coated with titanium nitride (TiN) and one with amorphous silicon (a-Si) immediately following fabrication. One chamber remained uncoated throughout, and the last chamber was first tested without any coating, and then coated with a-Si following a series of heat treatments. The outgassing rate of each chamber was measured at room temperatures between 15 and 30 deg C following bakes at temperatures between 90 and 400 deg C. Measurements for bare steel showed a significant reduction in the outgassing rate by more than a factor of 20 after a 400 deg C heat treatment (3.5 x 10{sup 12} TorrL s{sup -1}cm{sup -2} prior to heat treatment, reduced to 1.7 x 10{ sup -13} TorrL s{sup -1}cm{sup -2} following heat treatment). The chambers that were coated with a-Si showed minimal change in outgassing rates with heat treatment, though an outgassing rate reduced by heat treatments prior to a-Si coating was successfully preserved throughout a series of bakes. The TiN coated chamber exhibited remarkably low outgassing rates, up to four orders of magnitude lower than the uncoated stainless steel. An evaluation of coating composition suggests the presence of elemental titanium which could provide pumping and lead to an artificially low outgassing rate. The outgassing results are discussed in terms of diffusion-limited versus recombination-limited processes.

  15. Local total and radiative heat-transfer coefficients during the heat treatment of a workpiece in a fluidised bed

    International Nuclear Information System (INIS)

    Gao, W.M.; Kong, L.X.; Hodgson, P.D.

    2006-01-01

    The heat-transfer coefficients around a workpiece immersed in an electrically heated heat treatment fluidised bed were studied. A suspension probe designed to simulate a workpiece of complex geometry was developed to measure local total and radiative heat-transfer coefficients at a high bed temperature. The probe consisted of an energy-storage region separated by insulation from the fluidised bed, except for the measuring surface, and a multi-thermocouple measurement system. Experiments in the fluidised bed were performed for a fluidising medium of 120-mesh alumina, a wide temperature range of 110-1050 deg. C and a fluidising number range of 1.18-4.24. It was found that the workpiece surface temperature has a more significant effect on heat transfer than the bed temperature. The total heat-transfer coefficient at the upper surface of the workpiece sharply decreased at the start of heating, and then steadily increased as heating progressed, while a sharp decrease became a rapid increase and then a slow increase for the radiative heat-transfer coefficient. A great difference in the heat-transfer coefficients around the workpiece was observed

  16. Microbial safety control of compost material with cow dung by heat treatment.

    Science.gov (United States)

    Gong, Chun-ming

    2007-01-01

    Various kinds of pathogenic bacteria derived from the intestinal tract of animals exist in compost material like cow dung. In order to sterilize the pathogenic bacteria completely in compost material, the cow dung was put into a heat treatment machine in pilot plan, and harmless condition in short time was examined. The results indicated, pathogenic indicator bacteria such as coliform bacteria, fecal coliform, Escherichia coli and salmonella were all 106 cfu/g dw at the beginning, died rapidly when cow dung temperature rose to above 50 degrees C, and not detected at 54-68 degrees C for 6-24 h heat treatment. Coliform bacteria and salmonella in heated cow dung were not detected by re-growth culture and enrichment culture examination. Moreover, it was hardly influenced on the fermentation ability of composting microbe, organic decomposition bacteria. During heat treatment, the mesophile decreased rapidly and the thermophile stabilized or increased, and the most of composting microbe were bacillus in cow dung by fluorescence microscope, this indicated that bacillus was dominator and composting microbe in composting process.

  17. Influence of Heat Treatments on Carotenoid Content of Cherry Tomatoes

    Directory of Open Access Journals (Sweden)

    Laura D'Evoli

    2013-07-01

    Full Text Available Tomatoes and tomato products are rich sources of carotenoids—principally lycopene, followed by β-carotene and lutein. The aim of this work was to study the effect of heat treatment on carotenoid content in cherry tomatoes. Raw and canned products were sampled and analysed; furthermore whole, skin and pulp fractions of cherry tomatoes were analysed when raw and home-processed, in order to better understand heat treatment effects. Lycopene content in canned tomatoes was two-fold higher than in raw tomatoes (11.60 mg/100 g versus 5.12 mg/100 g. Lutein and β-carotene were respectively 0.15 mg/100 g and 0.75 mg/100 g in canned tomatoes versus 0.11 mg/100 g and 1.00 mg/100 g in raw tomatoes. For home-processed tomatoes, β-carotene and lutein showed a content decrease in all thermally treated products. This decrease was more evident for β-carotene in the skin fraction (−17%, while for lutein it was greater in the pulp fraction (−25%. Lycopene presented a different pattern: after heat treatment its concentration increased both in the whole and in pulp fractions, while in the skin fraction it decreased dramatically (−36%. The analysis of the isomers formed during the thermal treatment suggests that lycopene is rather stable inside the tomato matrix.

  18. Influence of Heat Treatments on Carotenoid Content of Cherry Tomatoes.

    Science.gov (United States)

    D'Evoli, Laura; Lombardi-Boccia, Ginevra; Lucarini, Massimo

    2013-07-31

    Tomatoes and tomato products are rich sources of carotenoids-principally lycopene, followed by β-carotene and lutein. The aim of this work was to study the effect of heat treatment on carotenoid content in cherry tomatoes. Raw and canned products were sampled and analysed; furthermore whole, skin and pulp fractions of cherry tomatoes were analysed when raw and home-processed, in order to better understand heat treatment effects. Lycopene content in canned tomatoes was two-fold higher than in raw tomatoes (11.60 mg/100 g versus 5.12 mg/100 g). Lutein and β-carotene were respectively 0.15 mg/100 g and 0.75 mg/100 g in canned tomatoes versus 0.11 mg/100 g and 1.00 mg/100 g in raw tomatoes. For home-processed tomatoes, β-carotene and lutein showed a content decrease in all thermally treated products. This decrease was more evident for β-carotene in the skin fraction (-17%), while for lutein it was greater in the pulp fraction (-25%). Lycopene presented a different pattern: after heat treatment its concentration increased both in the whole and in pulp fractions, while in the skin fraction it decreased dramatically (-36%). The analysis of the isomers formed during the thermal treatment suggests that lycopene is rather stable inside the tomato matrix.

  19. The influence of distal-end heat treatment on deflection of nickel-titanium archwire.

    Science.gov (United States)

    Silva, Marcelo Faria da; Pinzan-Vercelino, Célia Regina Maia; Gurgel, Júlio de Araújo

    2016-01-01

    The aim of this in vitro study was to evaluate the deflection-force behavior of nickel-titanium (NiTi) orthodontic wires adjacent to the portion submitted to heat treatment. A total of 106 segments of NiTi wires (0.019 x 0.025-in) and heat-activated NiTi wires (0.016 x 0.022-in) from four commercial brands were tested. The segments were obtained from 80 archwires. For the experimental group, the distal portion of each segmented archwire was subjected to heat treatment (n = 40), while the other distal portion of the same archwire was used as a heating-free control group (n = 40). Deflection tests were performed in a temperature-controlled universal testing machine. Unpaired Student's t-tests were applied to determine if there were differences between the experimental and control groups for each commercial brand and size of wire. Statistical significance was set at p wire. Heat treatment applied to the distal ends of rectangular NiTi archwires does not permanently change the elastic properties of the adjacent portions.

  20. Effect of nitrite on the microbiological stability of canned Vienna sausages preserved by mild heat treatment or combinations of heat and irradiation

    International Nuclear Information System (INIS)

    Farkas, J.; Zukal, E.; Incze, K.

    1973-01-01

    Keeping quality of Vienna sausages packed in No. 1/5 cans (ca 200 g) with salt brine and heat treated with F 0 values in the range of 0.25-0.55 was studied as a function of sodium nitrate addition. In uninoculated cans the heat requirement of preservation proved to be about 0.3 F 0 in the presence of 300 ppm NaNO 2 . A heat treatment of 0.55 F 0 and 200 ppm NaNO 2 resulted in higher microbiological stability of cans inoculated with 2x10 4 /tin Clostridium sporogenes spores than a heat treatment of 1.9 F 0 without nitrite addition. The effect of the combination of heat treatment of 0.35-0.55 F 0 and 0.45 Mrad of gamma irradiation was also studied with inoculated cans. The combination of irradiation plus heat resulted in a higher microbiological stability of the samples than the reversed order of the treatments, but this synergistic effect could not be proved in all experiments. The addition of 200 ppm NaNO 2 was not as effective in increasing the shelf-life of combination treated samples as with the solely heat treated ones. In a medium composed of a 50% extract of Vienna sausages (pH 6.4, asub(w) 0.96) and inoculated with 10 5 per ml Clostridium sporogenes spores 100 ppm or more NaNO 2 was required to ensure microbiological stability of samples heat treated with F 0 0.4. In the range of the permitted concentration level for canned meat products, sodium nitrite did not influence the heat resistance of Clostridium sporogenes, but inhibited the germination of the surviving spores. (F.J.)

  1. Influence of heat treatment on physicochemical and rheological characteristics of natural yogurts

    Directory of Open Access Journals (Sweden)

    Juliana Aparecida Célia

    2017-08-01

    Full Text Available The aim of this study was to assess the influence of heat treatment on physicochemical and rheological characteristics of natural yogurts, as well as the influence of lyophilization process on natural yogurts after reconstitution. In the first experiment, three yogurt treatments were processed, as follows: Treatment 1, yogurt produced with raw refrigerated milk; Treatment 2, yogurt produced with refrigerated pasteurized milk; and Treatment 3, yogurt produced with UHT (ultra-high temperature milk, in addition to analyses of fat, protein, moisture, titratable acidity, and pH. The shelf life of yogurts at 1, 8, 15, 22, and 29 days of storage, as well as pH, acidity, syneresis, viscosity, viable lactic bacteria, and total coliforms were also assessed. In the second experiment, yogurts were submitted to lyophilization process, performed by scanning electron microscopy analysis and subsequently in those reconstituted, in addition to being assessed the physicochemical, rheological, and viable lactic bacteria characteristics. The results found in the first experiment showed that heat treatment was positive for viscosity, syneresis, and lactic bacteria, being viable until the 15th day of storage only for yogurts submitted to heat treatment. In the second experiment, lyophilization preserved the physicochemical characteristics of yogurts, but the number of initial lactic bacteria was different, also negatively affecting yogurt viscosity.

  2. Time-resolved x-ray laser induced photoelectron spectroscopy of isochoric heated copper

    International Nuclear Information System (INIS)

    Nelson, A.J.; Dunn, J.; Hunter, J.; Widmann, K.

    2005-01-01

    Time-resolved x-ray photoelectron spectroscopy is used to probe the nonsteady-state evolution of the valence band electronic structure of laser heated ultrathin (50 nm) copper. A metastable phase is studied using a 527 nm wavelength 400 fs laser pulse containing 0.1-2.5 mJ laser energy focused in a large 500x700 μm 2 spot to create heated conditions of 0.07-1.8x10 12 W cm -2 intensity. Valence band photoemission spectra are presented showing the changing occupancy of the Cu 3d level with heating are presented. These picosecond x-ray laser induced time-resolved photoemission spectra of laser-heated ultrathin Cu foil show dynamic changes in the electronic structure. The ultrafast nature of this technique lends itself to true single-state measurements of shocked and heated materials

  3. Analysis of residual stress relief mechanisms in post-weld heat treatment

    International Nuclear Information System (INIS)

    Dong, Pingsha; Song, Shaopin; Zhang, Jinmiao

    2014-01-01

    This paper presents a recent study on weld residual stress relief mechanisms associated with furnace-based uniform post-weld heat treatment (PWHT). Both finite element and analytical methods are used to quantitatively examine how plastic deformation and creep relaxation contribute to residual stress relief process at different stages of PWHT process. The key contribution of this work to an improved understanding of furnace based uniform PWHT can be summarized as follows: (1)Plastic deformation induced stress relief during PWHT can be analytically expressed by the change in material elastic deformation capacity (or elastic deformation limit) measured in terms of material yield strength to Young's modulus ratio, which has a rather limited role in overall residual stress relief during furnace based uniform PWHT. (2)The most dominant stress relief mechanism is creep strain induced stress relaxation, as expected. However, a rapid creep strain development accompanied by a rapid residual stress reduction during heating stage before reaching PWHT temperature is shown to contribute to most of the stress relief seen in overall PWHT process, suggesting PWHT hold time can be significantly reduced as far as residual stress relief is concerned. (3)A simple engineering scheme for estimating residual stress reduction is proposed based on this study by relating material type, PWHT temperature, and component wall thickness. - Highlights: • The paper clarified effects of plastic deformation and creep relaxation on weld residual stress relief during uniform PWHT. • Creep strain development is far more important than plastic strain, mostly completed even before hold time starts. • Plastic strain development is insignificant and be analytically described by a material elastic deformation capacity parameter. • An engineering estimation scheme is proposed for determining residual stress reduction resulted from furnace based PWHT

  4. Induction heat treatment of laser welds

    DEFF Research Database (Denmark)

    Bagger, Claus; Olsen, Flemming Ove; Sørensen, Joakim Ilsing

    2003-01-01

    of an induction coil. A number of systematic laboratory tests were then performed in order to study the effects of the coil on bead-on-plate laser welded samples. In these tests, important parameters such as coil current and distance between coil and sample were varied. Temperature measurements were made...... the laser beam as close as possible. After welding, the samples were quality assessed according to ISO 13.919-1 and tested for hardness. The metallurgical phases are analysed and briefly described. A comparison between purely laser welded samples and induction heat-treated laser welded samples is made......In this paper, a new approach based on induction heat-treatment of flat laser welded sheets is presented. With this new concept, the ductility of high strength steels GA260 with a thickness of 1.8 mm and CMn with a thickness of 2.13 mm is believed to be improved by prolonging the cooling time from...

  5. Heat Treatment of Buckypaper for Use in Volatile Organic Compounds Sampling

    Directory of Open Access Journals (Sweden)

    Jonghwa Oh

    2016-01-01

    Full Text Available Three types of buckypapers (BPs, two of them fabricated with arc discharge (AD single-walled carbon nanotubes (SWNTs (acetone-cleaned AD BP and methanol-cleaned AD BP and one with high-pressure carbon monoxide (HiPco SWNTs (HiPco BP, were heat-treated at different conditions to find the specific conditions for each type that improve the adsorption properties. Based on thermogravimetric analysis (TGA data, three heat treatment conditions were designed for the AD BPs and another three conditions for the HiPco BPs. Also, changes in weight and physical integrity before and after the heat treatment were considered. Heating at 300°C for 90 minutes was selected for acetone-cleaned AD BP, in which the BP kept its physical integrity and yielded a relatively high Brunauer, Emmett, and Teller (BET surface area (970 ± 18 m2/g, while methanol-cleaned AD BP was excluded because of its physical change. For HiPco BP, a condition of 300°C heating for 30 minutes was chosen as a relatively higher surface area (933 ± 54 m2/g and less weight loss (5% were observed.

  6. Relaxation of residual stress in MMC after combined plastic deformation and heat treatment

    International Nuclear Information System (INIS)

    Bruno, G.; Ceretti, M.; Girardin, E.; Giuliani, A.; Manescu, A.

    2004-01-01

    Neutron Diffraction shows that plastic pre-deformation and heat treatments have opposite effects on the residual stress in Al-SiC p composites. The thermal micro residual stress is relaxed or even reversed by pre-strains above 0.2%, but restored by heat treatments. The sense of relaxation changes above 400 deg. C (the mixing temperature)

  7. Degradation of Anthocyanin Content in Sour Cherry Juice During Heat Treatment

    Directory of Open Access Journals (Sweden)

    Lilla Szalóki-Dorkó

    2015-01-01

    Full Text Available Sour cherry juices made from two sour cherry cultivars (Érdi bőtermő and Kántorjánosi 3, were investigated to determine their total anthocyanin content and half-life of anthocyanins during heat treatment at different temperatures (70, 80 and 90 °C for 4 h. Before the heat treatment, Érdi bőtermő juice had higher anthocyanin concentration (812 mg/L than Kántorjánosi 3 juice (513 mg/L. The greatest heat sensitivity of anthocyanins was measured at 90 °C, while the treatments at 80 and 70 °C caused lower thermal degradation. The loss of anthocyanins in Érdi bőtermő juice after treatment was 38, 29 and 18 %, respectively, while in Kántorjánosi 3 juice losses of 46, 29 and 19 % were observed, respectively. At 90 °C sour cherry Érdi bőtermő juice had higher half-life (t1/2 of anthocyanins, while the Kántorjánosi 3 juice had higher t1/2 values at 70 °C. Cyanidin-3-glucosyl-rutinoside was present in higher concentrations in both cultivars (Érdi bőtermő: 348 and Kántorjánosi 3: 200 mg/L than cyanidin-3-rutinoside (177 and 121 mg/L before treatment. However, during the experiment, cyanidin-3-rutinoside was proved to be more resistant to heat. Comparing the two varieties, both investigated pigment compounds were more stable in Kántorjánosi 3 than in Érdi bőtermő. Degradation rate of anthocyanins was cultivar-dependent characteristic, which should be taken into account in the food production.

  8. Differences in heat-induced cell killing as determined in three mammalian cell lines do not correspond with the extent of heat radiosensitization

    International Nuclear Information System (INIS)

    Kampinga, H.H.; Jorritsma, J.B.M.; Burgman, P.; Konings, A.W.T.

    1986-01-01

    Three different cell lines, Ehrlich ascites tumour (EAT) cells, HeLa S 3 cells and LM mouse fibroblasts, were used to investigate whether or not the extent of heat killing (44 0 C) and heat radio-sensitization (44 0 C before 0-6 Gy X-irradiation) are related. Although HeLa cells were the most heat-resistant cell line and showed the least heat radiosensitization, we found that the most heat-sensitive EAT cells (D 0 , EAT = 8.0 min; D 0 , LM = 10.0 min; D 0 , HeLa = 12.5 min) showed less radiosensitization than the more heat-resistant LM fibroblasts (TERsub(HeLa)< TERsub(EAT)< TERsub(LM)). Therefore, it is concluded that the routes leading to heat-induced cell death are not identical to those determining heat radiosensitization. Furthermore the inactivation of DNA polymerase α and β activities by heat seemed not to correlate with heat survival alone but showed a positive relationship to heat radiosensitization. The possibility of these enzymes being a determinant in heat radiosensitization is discussed. (author)

  9. Effect of Thermal Mechanical Behaviors of Cu on Stress Distribution in Cu-Filled Through-Silicon Vias Under Heat Treatment

    Science.gov (United States)

    Zhao, Xuewei; Ma, Limin; Wang, Yishu; Guo, Fu

    2018-01-01

    Through-silicon vias (TSV) are facing unexpected thermo-mechanical reliability problems due to the coefficient of thermal expansion (CTE) mismatch between various materials in TSVs. During applications, thermal stresses induced by CTE mismatch will have a negative impact on other devices connecting with TSVs, even leading to failure. Therefore, it is essential to investigate the stress distribution evolution in the TSV structure under thermal loads. In this report, TSVs were heated to 450°C at different heating rates, then cooled down to room temperature after a 30-min dwelling. After heating treatment, TSV samples exhibited different Cu deformation behaviors, including Cu intrusion and protrusion. Based on the different Cu deformation behaviors, stress in Si around Cu vias of these samples was measured and analyzed. Results analyzed by Raman spectrums showed that the stress distribution changes were associated with Cu deformation behaviors. In the area near the Cu via, Cu protrusion behavior might aggravate the stress in Si obtained from the Raman measurement, while Cu intrusion might alleviate the stress. The possible reason was that in this area, the compressive stress σ_{θ } induced by thermal loads might be the dominant stress. In the area far from the Cu via, thermal loads tended to result in a tensile stress state in Si.

  10. Comparison of the heat shock response induced by conventional heating and two methods of delivery of pulsed radiofrequency energy

    International Nuclear Information System (INIS)

    Laurence, J.A.; University of Sydney, NSW; McKenzie, D.R.; Veas, L.; French, P.W.

    2002-01-01

    Full text: In 2001, we published a (hypothetical) mechanism by which radiofrequency (RF) radiation from mobile phones could induce cancer, via the chronic induction of the heat shock response (HSR). This hypothesis provides the focus for our research. Other groups have reported induction of the HSR by RF at apparently non thermal levels. The aim of this study was to determine whether the HSR induced by RF is (a) truly non thermal and (b) quantitatively or qualitatively different from that induced by conventional heating of cells. A rat mast cell line, RBL-2H3, was chosen as the target RBL-2H3 cells were exposed in an air incubator at 41.1 deg C for 45 minutes and 75 minutes, and then returned to a 37 deg C incubator. Sham exposures were performed in the same air incubator at 37 deg C. Cells were exposed for 1 hour in the two pulsed RF exposure systems. The first was a converted 750W microwave oven that emits a short burst of 2.45GHz pulses at the start of each contiguous six minute period. This exposes cells to an average specific energy absorption rate (SAR) of 20W/kg. The second system was a TEM cell, which simulates. GSM pulses - the earner frequency is 0.9GHz pulse modulated at 217Hz. The SAR was approx 0.1W/kg. Both of these exposure systems are housed in incubators maintained at 37 deg C. Sham exposures were performed in the two systems with the same conditions but with no RF radiation present. Cell samples for the conventional heating and microwave exposures were taken 0, 2. 5, 5 and 20 hours after exposure, and expression of heat shock proteins hsp 110, 90, 70, 60 and 56 were determined by Western Blotting and compared between exposures

  11. Effects of Heat Treatment on the Microstructure and Mechanical Properties of Low-Carbon Steel with Magnesium-Based Inclusions

    Science.gov (United States)

    Zhang, Jian; Feng, Pei-Hsien; Pan, Yan-Chi; Hwang, Weng-Sing; Su, Yen-Hao; Lu, Muh-Jung

    2016-10-01

    The effects of heat treatment on the microstructure and mechanical properties of Mg-containing (7 ppm), low-carbon commercial steel (SS400) were investigated. Twenty different heat treatment paths were performed using a Gleeble 1500 thermomechanical simulator. It was observed by using an optical microscope that as the cooling rate increased and holding temperature decreased, the volume fractions of pearlite, Widmanstätten ferrite, and grain boundary allotriomorphs ferrite fell, whereas that of acicular ferrite (AF) increased. Quantifying the fractions of AF and other phases by using electron backscatter diffraction shows that the heat treatment path with a cooling rate of 20 K/s and holding temperature of 723 K (450 °C) induced the highest volume fraction (44 pct) of AF. As such, the toughness of the sample was increased 12.4 times compared with that observed in the sample containing 4 pct AF. Typical inclusions were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy. The results showed that the magnesium-based complex inclusions could act as nucleation sites of AF. Inclusions with a size of about 5 μm can serve as heterogeneous nucleation sites for AF. Mg-containing SS400 steel also has excellent hot-ductility in the temperature range of 973 K to 1273 K (700 °C to 1000 °C), and the minimum percentage reduction in area (R.A pct) value of around 63 pct at 1073 K (800 °C).

  12. Monitoring the Induction of Heat Shock Factor 1/Heat Shock Protein 70 Expression following 17-Allylamino-Demethoxygeldanamycin Treatment by Positron Emission Tomography and Optical Reporter Gene Imaging

    Directory of Open Access Journals (Sweden)

    Mikhail Doubrovin

    2012-01-01

    Full Text Available The cell response to proteotoxic cell stresses is mediated primarily through activation of heat shock factor 1 (HSF1. This transcription factor plays a major role in the regulation of the heat shock proteins (HSPs, including HSP70. We demonstrate that an [124I]iodide-pQHNIG70 positron emission tomography (PET reporter system that includes an inducible HSP70 promoter can be used to image and monitor the activation of the HSF1/HSP70 transcription factor in response to drug treatment (17-allylamino-demethoxygeldanamycin [17-AAG]. We developed a dual imaging reporter (pQHNIG70 for noninvasive imaging of the heat shock response in cell culture and living animals previously and now study HSF1/HSP70 reporter activation in both cell culture and tumor-bearing animals following exposure to 17-AAG. 17-AAG (10–1,000 nM induced reporter expression; a 23-fold increase was observed by 60 hours. Good correspondence between reporter expression and HSP70 protein levels were observed. MicroPET imaging based on [124I]iodide accumulation in pQHNIG70-transduced RG2 xenografts showed a significant 6.2-fold reporter response to 17-AAG, with a corresponding increase in tumor HSP70 and in tumor human sodium iodide symporter and green fluorescent protein reporter proteins. The HSF1 reporter system can be used to screen anticancer drugs for induction of cytotoxic stress and HSF1 activation both in vitro and in vivo.

  13. Investigation of heat distribution during magnetic heating treatment using a polyurethane–ferrofluid phantom-model

    International Nuclear Information System (INIS)

    Henrich, F.; Rahn, H.; Odenbach, S.

    2014-01-01

    Magnetic heating treatment can be used as an adjuvant treatment for cancer therapy. In this therapy, magnetic nanoparticles are enriched inside the tumour and exposed to an alternating magnetic field. Due to magnetic losses the temperature in the tumour rises. The resulting temperature profile inside the tumour is useful for the therapeutic success. In this context heat transfer between tissue with nanoparticles and tissue without nanoparticles is a highly important feature which is actually not understood in detail. In order to investigate this, a phantom has been created which can be used to measure the temperature profile around a region enriched with magnetic nanoparticles. This phantom is composed of a material, which has similar thermal conductivity as human tissue. A tempered water bath surrounds the phantom to establish a constant surrounding temperature simulating the heat sink provided by the human body in a real therapeutic application. It has been found that even at a low concentration of magnetic nanoparticles around 13 mg/ml, sufficient heating of the enriched region can be achieved. Moreover it has been observed that the temperature drops rapidly in the material surrounding the enriched region. Corresponding numerical investigations provide a basis for future recalculations of the temperature inside the tumour using temperature data obtained in the surrounding tissue. - Highlights: • The temperature profile by magnetic hyperthermia was examined. • A model was built to get a deeper understanding of the temperature profile. • The temperature profile of the model inside magnetic fields was measured. • Based on the model a simulation of the temperature profile was performed. • The simulated temperature profile agreed well with the measured profile

  14. Evaluation of carbon diffusion in heat treatment of H13 tool steel under different atmospheric conditions

    OpenAIRE

    Ramezani, Maziar; Pasang, Timotius; Chen, Zhan; Neitzert, Thomas; Au, Dominique

    2015-01-01

    Although the cost of the heat treatment process is only a minor portion of the total production cost, it is arguably the most important and crucial stage on the determination of material quality. In the study of the carbon diffusion in H13 steel during austenitization, a series of heat treatment experiments had been conducted under different atmospheric conditions and length of treatment. Four austenitization atmospheric conditions were studied, i.e., heat treatment without atmospheric contro...

  15. Heat stroke during long-term clozapine treatment: should we be concerned about hot weather?

    OpenAIRE

    Hoffmann, Maurício Scopel; Oliveira, Lucas Mendes; Lobato, Maria Inês Rodrigues; Belmonte-de-Abreu, Paulo

    2016-01-01

    Objective To describe the case of a patient with schizophrenia on clozapine treatment who had an episode of heat stroke. Case description During a heat wave in January and February 2014, a patient with schizophrenia who was on treatment with clozapine was initially referred for differential diagnose between systemic infection and neuroleptic malignant syndrome, but was finally diagnosed with heat stroke and treated with control of body temperature and hydration. Comments This report aims to...

  16. Synergistic skin heat shock protein expression in response to combined laser treatment with a diode laser and ablative fractional lasers.

    Science.gov (United States)

    Paasch, Uwe; Sonja, Grunewald; Haedersdal, Merete

    2014-06-01

    Diode laser-based skin heating has been shown to minimise scars by interfering with wound healing responses through the induction of heat shock proteins (HSP). HSP are also induced after ablative fractional laser (AFXL) wound healing. AFXL itself is highly recommended for scar treatment. Therefore, the sequential combination of both modalities may produce superior outcomes. The aim of this study was to examine the pretreatment effects of a diode laser before AFXL on wound healing responses in terms of HSP up-regulation in an in vitro model. Immediate responses and responses on days 1, 3 or 6 post-procedure were studied in an in vitro porcine skin model (n = 240). Untreated samples served as control. Immunohistochemical investigation (Hsp70) was performed in all untreated controls, diode laser-, AFXL-, and in diode laser + AFXL-treated samples. Hsp70 was shown to be up-regulated by all interventions between days 1 and 6 after interventions. The largest effect was caused by the combination of a diode laser and an AFXL procedure. Diode laser exposure induces a skin HSP response that can be further enhanced by sequential AFXL treatment. Clinical studies are necessary to investigate the dose response of HSP on scar formation and refine suitable laser exposure settings.

  17. Heat-induced accumulation and futile cycling of trehalose in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Hottiger, T.; Schmutz, P.; Wiemken, A.

    1987-01-01

    Heat shock resulted in rapid accumulation of large amounts of trehalose in Saccharomyces cerevisiae. In cultures growing exponentially on glucose, the trehalose content of the cells increased from 0.01 to 1 g/g of protein within 1 h after the incubation temperature was shifted from 27 to 40 0 C. When the temperature was readjusted to 27 0 C, the accumulated trehalose was rapidly degraded. In parallel, the activity of the trehalose-phosphate synthase, the key enzyme of trehalose biosynthesis, increased about six fold during the heat shock and declined to normal level after readjustment of the temperature. Surprisingly, the activity of neutral trehalase, the key enzyme of trehalose degradation, also increased about threefold during the heat shock and remained almost constant during recovery of the cells at 27 0 C. In pulse-labeling experiments with [ 14 C] glucose, trehalose was found to be turned over rapidly in heat-shocked cells, indicating that both anabolic and catabolic enzymes of trehalose metabolism were active in vivo. Possible functions of the heat-induced accumulation of trehalose and its rapid turnover in an apparently futile cycle during heat shock are discussed

  18. Characterization of residual stresses in heat treated Ti-6Al-4V forgings by machining induced distortion

    Directory of Open Access Journals (Sweden)

    Werner E.

    2010-06-01

    Full Text Available To provide a solid base for improved material exploitation in dimensioning calculations it is necessary to determine the stress state in the part prior to service loading. In order to achieve higher material strength at elevated temperatures, the surface temperature gradient with respect to time has to be sufficiently high during heat treatment. This results in non-negligable residual stresses that can reduce the allowable load level upon which yielding occurs. For titanium alloys there are two common heat treatments, namely solution treatment and mill annealing. The latter one is the method of choice within the presented project. Mill annealing is utilized in order to significantly reduce the residual stresses in the parts without loosing much of the improved strength at elevated temperatures. Quantification of residual stresses is done by solving an inverse problem. From the measurement of distortion, induced by dividing the investigated part, the residual stress state can be calculated via analytical modeling or correlation with finite element models. To assure a minimum perturbation of the residual stress state during specimen production, dividing of the part is accomplished by electric discharge machining. The parts of interest are v-shaped prisms with a length of approximatly 450 mm and a thickness in the cross sectional area from about 20 mm to 45 mm. Figure 1(a shows the forged part and 1(b the dimensions of the cross section in millimeters as well as the material properties considered in the finite element model. The heat exchange between the part and the environment is modelled as heat transfer by convection superimposed with heat radiation. Since the parts are exposed to air during forging and heat treatment, the surface develops a strongly adhesive oxide layer, the so called alpha-case. After forging the parts are cooled in air and heat treated at a temperature of 720° C for a duration of 120 min. Subsequent air cooling and

  19. Preliminary heat treatment of 4KhM2Fch die steel

    International Nuclear Information System (INIS)

    Leonidov, V.M.; Berezkin, Y.A.; Nikitenko, E.V.

    1986-01-01

    To improve the machinability and preparation of the structure for hardening, die steels are given a preliminary treatment which provides a reduction in hardness as a result of separation in the structure of the carbide and ferrite phases, coagulation of the carbides, and acquisition by them of a granular form and also the obtaining of fine grains and a uniform distribution of the structural constituents. The microstructure was evaluated after etching in 4% nital on an MIM-8M microscope. The 4KhM2Fch steel was given a preliminary heat treatment of normalize and anneal. It was concluded that for 4KhM2Fch steel a preliminary heat treatment of normalizing from 950 0 C with a hold of 1.5-2 h, annealing at 750-760 0 C with a hold of 2-3 h, cooling to the isothermal temperature of 670-680 0 C with a hold of 3-4 h, and further air cooling is recommended. The structure after such a heat is granular pearlite with a rating 1-2 and a hardness of 220-250 HB

  20. The effect of postproduction heat treatment on γ-TiAl alloys produced by the GTAW-based additive manufacturing process

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yan; Cuiuri, Dominic; Li, Huijun; Pan, Zengxi, E-mail: zengxi@uow.edu.au; Shen, Chen

    2016-03-07

    Postproduction heat treatments were carried out on additively manufactured γ-TiAl alloys that were produced by using the gas tungsten arc welding (GTAW) process. The microstructural evolution and mechanical properties of both as-fabricated and heat-treated specimens were investigated to assess the effect of different heat treatment conditions, by using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Neutron Diffraction and tensile tests. The results indicated that heat treatment promotes the formation of the γ phase in the majority region after heat treatment at 1200 °C for 24 h, while a fully lamellar structure was formed in the near-substrate zone. The response to heat treatment at 1060 °C/24 h was markedly different, producing a fine lamellar structure with differing sizes in the majority region and near-substrate zone. These various microstructural characteristics determined the mechanical properties of the heat-treated samples. The heat-treated samples at 1200 °C/24 h exhibited lower UTS and microhardness values but higher ductility than the as-fabricated samples without heat treatment, while the 1060 °C/24 h heat treatment resulted in higher UTS and microhardness values but lower ductility. Due to the homogenous microstructure in the majority region after each postproduction heat treatment, the tensile properties were similar for both the build direction (Z) and travel direction (Y), thereby minimising the anisotropy that is exhibited by the as-fabricated alloy prior to heat treatment.

  1. Effect of Carbon Nanofiber Heat Treatment on Physical Properties of Polymeric Nanocomposites—Part I

    Directory of Open Access Journals (Sweden)

    Khalid Lafdi

    2007-01-01

    Full Text Available The definition of a nanocomposite material has broadened significantly to encompass a large variety of systems made of dissimilar components and mixed at the nanometer scale. The properties of nanocomposite materials also depend on the morphology, crystallinity, and interfacial characteristics of the individual constituents. In the current work, vapor-grown carbon nanofibers were subjected to varying heat-treatment temperatures. The strength of adhesion between the nanofiber and an epoxy (thermoset matrix was characterized by the flexural strength and modulus. Heat treatment to 1800C∘ demonstrated maximum improvement in mechanical properties over that of the neat resin, while heat-treatment to higher temperatures demonstrated a slight decrease in mechanical properties likely due to the elimination of potential bonding sites caused by the elimination of the truncated edges of the graphene layers. Both the electrical and thermal properties of the resulting nanocomposites increased in conjunction with the increasing heat-treatment temperature.

  2. Heat treatment on keruing and light red meranti: The effect of heat exposure at different levels of temperature on bending strength properties

    Science.gov (United States)

    Noh, Nur Ilya Farhana Md; Ahmad, Zakiah

    2017-11-01

    Heat treatment on timbers is a process of applying heat to modify and equip the timbers with new improvised characteristics. It is environmental friendly compared to the common practice of treating timber by chemical preservatives. Malaysian hardwood timbers namely Keruing and Light Red Meranti which are in green condition were heat treated at temperature 150°C, 170°C, 190°C and 210°C, in a specially designed electronic furnace within one hour duration. The objectives were to determine the effect of heat treatment on bending strength properties of heat treated timbers in terms of Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) and to examine the significance changes at each temperature level. Untreated samples for each species were used as a control sample. The results indicated that the bending strength properties for both species of timbers were affected by the heat exposure. Both MOE and MOR values for heat treated Keruing were increased when subjected to the temperature levels at 150°C, 170°C and 190°C except at 210°C. Heat treated Light Red Meranti shows the same pattern of increment on its MOE and MOR values after exposure to heat at three temperature levels applied and the values dropped at 210°C. However, for both of species, even though there were decrement occurred at 210°C, the value is still higher compared to the control sample. The increments of MOE and MOR values are an indicator that heat treatment had successfully improvised the bending strength properties of these two species of hardwood timber.

  3. Effect of the Heat Treatment on the Graphite Matrix of Fuel Element for HTGR

    International Nuclear Information System (INIS)

    Lee, Chungyong; Lee, Seungjae; Suh, Jungmin; Jo, Youngho; Lee, Youngwoo; Cho, Moonsung

    2013-01-01

    In this paper, the cylinder-formed fuel element for the block type reactor is focused on, which consists of the large part of graphite matrix. One of the most important properties of the graphite matrix is the mechanical strength for the high reliability because the graphite matrix should be enabled to protect the TRISO particles from the irradiation environment and the impact from the outside. In this study, the three kinds of candidate graphites and Phenol as a binder were chosen and mixed with each other, formed and heated for the compressive strength test. The objective of this research is to optimize the kinds and composition of the mixed graphite and the forming process by evaluating the compressive strength before/after heat treatment (carbonization of binder). In this study, the effect of heat treatment on graphite matrix was studied in terms of the density and the compressive strength. The size (diameter and length) of pellet is increased by heat treatment. Due to additional weight reduction and swelling (length and diameter) of samples the density of graphite pellet is decreased from about 2.0 to about 1.7g/cm 3 . From the mechanical test results, the compressive strength of graphite pellets was related to the various conditions such as the contents of binder, the kinds of graphite and the heat treatment. Both the green pellet and the heat treated pellet, the compressive strength of G+S+P pellets is relatively higher than that of R+S+P pellets. To optimize fuel element matrix, the effect of Phenol and other binders, graphite composition and the heat treatment on the mechanical properties will be deeply investigated for further study

  4. Protective effects of red grape (Vitis vinifera) juice through restoration of antioxidant defense, endocrine swing and Hsf1, Hsp72 levels in heat stress induced testicular dysregulation of Wister rat.

    Science.gov (United States)

    Halder, Soma; Sarkar, Mrinmoy; Dey, Sananda; Kumar Bhunia, Sujay; Ranjan Koley, Alok; Giri, Biplab

    2018-01-01

    Ability of red grape juice (RGJ), a known antioxidant, on testis of adult Wister rat to protect from oxidative stress induced damages by heat stress has been investigated in this study. Heat stress was induced maintaining body and testicular temperature at 43°C for 30min/day for 15 days using a hyperthermia induction chamber. Four groups of rats (n=6 per group) comprising of Group-I (control) -kept at 32°C, Group-II -exposed to heat stress alone, Group-III received RGJ (0.8ml/rat/day) alone and Group-IV -exposed to heat stress and received RGJ at same dose. Analysis of blood and testicular tissue exhibited significant reduction in serum testosterone, testicular superoxide dismutase, testicular catalase and testicular glutathione (all p rise in the level of serum corticosteroid, testicular lipid peroxidase and the apoptotic enzyme caspase-3 of testis (all p < 0.001) were observed along with substantial increase in testicular Hsp72 and Hsf-1, and decrease in 17β-HSD3 were noted in heat stressed rats compared to controls. In Group-IV rats, RGJ administration could restore these parameters to normal levels. The signs of retention were clear in Group-IV rats and found to be significantly different as compared to that of the Group-II rats. In testicular histology of rats exposed to heat stress alone revealed remarkable germ cell degeneration and tubular deformations which were prevented by RGJ treatment (Group-IV). The reduced number of sperm level in Group-II also restored in RGJ treatment (Group-IV). The above results indicate that consumption of RGJ may substantially protect testis from heat stress induce dysfunctions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Flow induced vibration in shell and tube heat exchangers

    International Nuclear Information System (INIS)

    Soper, B.M.H.

    1981-01-01

    Assessing heat exchanger designs, from the standpoint of flow induced vibration, is becoming increasingly important as shell side flow velocities are increased in a quest for better thermal performance. This paper reviews the state of the art concerning the main sources of vibration excitation, i.e. vortex shedding resonance, turbulent buffeting, fluidelastic instability and acoustic resonance, as well as the structural dynamics of the tubes. It is concluded that there are many areas which require further investigation but there are sufficient data available at present to design, with reasonable confidence, units that will be free from flow induced vibration. Topics which are considered to be key areas for further work are listed

  6. Heat treatments and low temperature fracture toughness of a Ti-6A1-4V alloy

    International Nuclear Information System (INIS)

    Nagai, K.; Hiraga, K.; Ishikawa, K.; Ogata, T.

    1984-01-01

    Titanium alloy is one of the reliable structural materials for cryogenic use owing to its high strength, high specific strength and low thermal conductivity. Heat treatment is one method of controlling the normally poor fracture toughness of this alloy at ambient temperature. However, there have been few attempts to improve the low temperature fracture toughness by heat treatment. This study was conducted to elucidate the effects of heat treatments on the low temperature fracture toughness in a Ti-6A1-4V alloy. The effects of the heat treatments were as follows: the beta treatment was a very feasible method to improve the low temperature fracture properties; the alpha+beta treatment was favorable for the increment in the low temperature ductility but did not largely improve the fracture toughness; the double treatment yielded good ductility but was not useful for improving the fracture toughness

  7. Treatment of lithium induced tremor with atenolol.

    Science.gov (United States)

    Davé, M

    1989-03-01

    This is the first report on the successful treatment of one patient with lithium induced tremor with hydrophilic atenolol, which is a relatively selective beta 1 adrenergic receptor blocker. Atenolol's advantages over lipophilic beta blockers in the treatment of lithium induced tremor are discussed.

  8. Effect of Ultrastructure on Changes of Textural Characteristics between Crisp Grass Carp (Ctenopharyngodon Idellus C.Et V) and Grass Carp (Ctenopharyngodon Idellus) Inducing Heating Treatment.

    Science.gov (United States)

    Lin, Wan-Ling; Yang, Xian-Qing; Li, Lai-Hao; Hao, Shu-Xian; Wang, Jin-Xu; Huang, Hui; Wei, Ya; Wu, Yan-Yan

    2016-02-01

    The research studies the ultrastructure effect on texture of crisp grass carp (CGC) and grass carp (GC) fillets inducing heating for 15, 25, and 40 min with boiling water. After heating, the hardness, fracturability, springiness, chewiness, resilience, and cohesiveness of CGC were higher than that of raw CGC, whereas the all textural characteristics of heating GC were lower obviously than that of raw GC. The hardness, fracturability, springiness, chewiness, resilience, and cohesiveness of CGC for heating 15 min were higher by 6.3%, 9.0%, 27.0%, 71.8%, 9.4%, and 23.9%, respectively, than that of raw CGC (RCGC). The hardness increasing of CGC flesh with the extension of heating time related closely to more coagulating connective tissue in interstitial spaces, especially relating to smaller muscle fiber diameter and denser muscle fiber density. The more and larger spaces between fiber and fiber with the extension of heating time results in the decrease of cohesiveness and resilience of CGC flesh. For chewiness, the stronger chewiness of cooked CGC associated with more detachment of myofiber-myocommata and fiber-fiber. Overall, the results show that the changes of texture characteristics of CGC fillet with extension of heating time correlates positively with the ultrastructure. © 2016 Institute of Food Technologists®

  9. Patterns of indole alkaloids synthesis in response to heat shock, 5-azacytidine and Na-butyrate treatment of cultured catharanthus roseus mesophyll protoplasts

    International Nuclear Information System (INIS)

    Saleem, M.; Cutler, A.J.

    1986-01-01

    Alkaloids of C. roseus are in high demand for therapeutic and other reasons. Cultured Catharanthus cells can produce limited quantities of these alkaloids. The authors have found that cultured mesophyll protoplasts in the presence of 14 C-Tryptamine are capable of synthesizing alkaloids. The pattern of alkaloids synthesis changes when protoplasts are subjected to a heat shock at 37 0 C. The heat shocked protoplasts incorporated 33% more 14 C-Tryptamine and produced 3 new types of alkaloids. Treatment of protoplasts with 5-azacytidine, a DNA hypomethylating agent and Na-butyrate which induces hyperacetylation of histones produced qualitative and quantitative changes in the alkaloid pattern. Four new alkaloids following the above treatments were detected by TLC and HPLC of the extracts. It is suggested that the alkaloid pattern of the cultured protoplasts can be altered by treatment with compounds known as regulators of gene expression. Work is in progress to isolate and identify these new alkaloids

  10. Influence of heat treatment temperature on bonding and oxidation ...

    Indian Academy of Sciences (India)

    Administrator

    Diamond; TiO2 film; heat treatment temperature; anti-oxidation; mechanical properties. 1. Introduction. Due to its ..... figure 4a, which was due to the change of chemical envi- ronment of ... graphite, diamond, diamond-like carbon and carbon.10.

  11. SiO2 sol-gel films after ammonia and heat two-step treatments

    International Nuclear Information System (INIS)

    Zhang Chunlai; Wang Biyi; Tian Dongbin; Yin Wei; Jiang Xiaodong; Yuan Xiaodong; Yan Lianghong; Zhang Hongliang; Zhao Songnan; Lv Haibing

    2008-01-01

    SiO 2 thin films were deposited using tetraethoxylsilane as precursor, ammonia as catalyst on K9 glass by sol-gel method. These films were post-treated by ammonia and heat. The properties of the coatings were characterized by ellipsometer, UV-vis spectrophotometry, FTIR-spectroscopy, scanning probe microscope and contact angle measurement apparatus. The resuits indicate that the thickness of the films with ammonia and heat treatment tend to decrease. Both the refractive index and water contact angle increase after ammonia treatment. However, they both decrease after heat treatment. The former increases by 0.236 for the first step, then decreases by 0.202 for the second. The latter increases to 58.92 degree, then decreases to 38.07 degree. The transmittance of the coatings turn to be better and continuously shift to short wave by UV-vis spectrophotometry. The surface becomes smoother by AFM after the two-step treatment. (authors)

  12. Effects of heat treatments on laser welded Mg-rare earth alloy NZ30K

    International Nuclear Information System (INIS)

    Dai Jun; Huang Jian; Li Min; Li Zhuguo; Dong Jie; Wu Yixiong

    2011-01-01

    Highlights: → Firstly find the tadpole-shape precipitates in the welding joint. → The precipitation strengthening can account for 79% of the total strength. → The results can provide some insights on the application of Mg-RE alloy. - Abstract: In this study, the effects of heat treatments on the quality of laser welded Mg-rare earth alloy NZ30K were systematically studied. The microstructure and mechanical properties of joints, welded by a 15 kW high power CO 2 laser, under different heat treatments had been tested and analyzed. The results indicated that the heat treatment plays an important role in the mechanical strength of laser welded joint of NZ30K. The microstructure of samples after the solution treatment as well as aging treatment is different from that of the as-received welded joint. For solution treatment, although the microstructure is much different from that of as-received welded joint, the solution strengthening effect is not obvious. There are lots of precipitates in the fusion zone after the aging treatment, which will significantly enhance the ultimate tensile strength (UTS) and the yield tensile strength (YTS) of the welding joint. 79% of YTS is caused by precipitation strengthening. Therefore, the results implied that the UTS and YTS can be greatly improved by proper heat treatment.

  13. Effect of heat-treatment on toughness and strength properties of C-Mn steel

    International Nuclear Information System (INIS)

    Mohd bin Harun; Goh Kian Seong; Jasmin binti Baba

    1991-01-01

    The strength and toughness of the heat-treated and tempered C-Mn are studied. Two types of heat-treatment have been carried out with the specimens in an argon gas. The variation in the fracture surfaces of the heat-treated and tempered specimens with impact test temperature is discussed also

  14. Effect of heat treatment of toughness and strength properties of C-Mn steel

    International Nuclear Information System (INIS)

    Mohamad bin Harun; Goh Kian Seong; Yasmin binti Baba

    1989-01-01

    The strength and toughness of the heat-treated and tempered C-Mn are studied. Two type of heat-treatments have been carried out with the specimens in an argon gas. The variation in the fracture surfaces of the heat-treated and tempered specimens with impact test temperatures also is discussed. (author)

  15. Impact of Heat Treatment on the Freezing Points of Cow and Goat Milk

    Directory of Open Access Journals (Sweden)

    Bohumíra Janštová

    2009-01-01

    Full Text Available The aim of this study was to monitor the impact of heat treatment variables on the freezing point of cow and goat milk. The freezing point (FP was established in 30 bulk tank samples of goat milk and in 30 bulk tank samples of cow milk which were subject to laboratory heat treatment at temperatures of 72 °C (A, 85 °C (B, 95 °C (C, with the same exposition times of 20 s. Freezing point measurements of raw and heat-treated milk were carried out in compliance with the Standard CTS 57 0538 by a thermistor cryoscope. The FP of raw cow milk increased with heat treatment from the initial values of -0.5252 ± 0.0114 °C (O by 0.0023 °C (A, 0.0034 °C (B and 0.0051°C (C. Changes in FP values of goat milk were detected, from its initial value of –0.5530 ± 0.0086 °C there was an increase in the FP depending on the mode of heat treatment due to pasteurization by an average of 0.0028 °C (A, 0.0036 °C (B and 0.0054 °C (C. The dynamics of the changes were similar both in goat and cow milk. Freezing point values in cow and goat milk differed (P ⪬ 0.01 when compared to the freezing point of untreated milk after the individual interventions as well as when compared between each other. An increase in the heat treatment temperature of cow and goat milk causes an increase in the freezing point (a shift towards zero. These results can be used in practice for checking the raw material in dairy industry.

  16. Heat treatment of transparent Yb:YAG and YAG ceramics and its influence on laser performance

    Science.gov (United States)

    Fujioka, Kana; Mochida, Tetsuo; Fujimoto, Yasushi; Tokita, Shigeki; Kawanaka, Junji; Maruyama, Momoko; Sugiyama, Akira; Miyanaga, Noriaki

    2018-05-01

    Composite transparent ceramic materials are promising for improving the performance of high-average-power lasers. A combination of room-temperature bonding via surface treatment by a fast atom beam and diffusion bonding via heating, which effectively controls the ion diffusion distance near the interface, makes the laser materials suitable for a variety of oscillator/amplifier. During the heat treatment of yttrium aluminum garnet (YAG) ceramics, the Si ions in the solid solution of the sintering aid incorporated within the grains were seen to segregate at the grain boundary, resulting in an increase of scattering sites. The number density and size of the scattering sites strongly depended on the post-heating temperature rather than the heating time. Specifically, heating at 1300 °C did not affect the transmittance of the YAG ceramic, whereas both the size and number of scattering sites substantially increased with a heat treatment at 1400 °C. The laser oscillation experiment using cryogenically-cooled Yb:YAG ceramics exhibited heating temperature dependence of the slope efficiency owing to the increasing scattering loss.

  17. A heat mathematical model of polymer composite cylinder during microwave treatment

    Directory of Open Access Journals (Sweden)

    S. V. Reznik

    2014-01-01

    Full Text Available Traditional technologies of producing epoxy based polymer composite materials (PCM require a long-term and energy consuming thermal processing. Microwave heating could be used as an alternative technology for heating work pieces made of PCM; this would allow to reduce treatment time and energy consumption significantly. A mathematical model of temperature distribution inside a cylindrical composite system during microwave treatment was investigated in this paper. The model includes a hollow PCM cylinder made of an epoxy binder and carbon fibers and a solid cylindrical mandrel. Theoretical and experimental results on the temperature state of the system were analyzed and discussed.

  18. Phase transformation and hardness of SS 316 L steel cast alloy after heat treatment at high temperature

    International Nuclear Information System (INIS)

    Hidayat, S.; Prayitno, D. H.

    2000-01-01

    Heat treatment Study of SS 316 L cast alloy at high temperature was conducted. The alloy of SS 316 L was melted by arc melting furnace in argon atmosphere. Heat treatment of SS 316 L casting alloy was carried out in tube furnace at 1400 o C for period of 1/2, 1, and 2 hours. The optical microscopic characterization showed that SS 316 L cast has got dendritic micro structure with ferrite as the primary phase. After the heat treatment, the ferrite phase underwent gradual decrease followed by an increase of the austenite phase. The heat treatment process also resulted in the formation of the new grain boundary. The hardness examination revealed that for longer period of the heat treatment, the hardness of SS 316 L increased. (author)

  19. The effects of heat treatment on physical and technological ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... ween 450 and 660 m altitudes in Cide-Sehdagi (Gercek et al., 1998; Dogu ... changes continue as the temperature is increased in ... Heat treatment slows water uptake and wood cell wall absorbs ...... The Effect of Boiling Time.

  20. Effect of heat treatment on anodic activation of aluminium by trace element indium

    Energy Technology Data Exchange (ETDEWEB)

    Graver, Brit [Department of Materials Science and Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Helvoort, Antonius T.J. van [Department of Physics, Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Nisancioglu, Kemal, E-mail: kemal.nisancioglu@material.ntnu.n [Department of Materials Science and Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)

    2010-11-15

    Research highlights: {yields} Indium segregation activates AlIn alloy surface anodically in chloride solution. {yields} Enrichment of In on Al surface can occur thermally by heat treatment at 300 {sup o}C. {yields} Increasing temperature homogenises indium in aluminium reducing anodic activation. {yields} Indium can activate AlIn surface by segregating through dealloying of aluminium. {yields} Anodic activation is caused by AlIn amalgam formation at aluminium surface. - Abstract: The presence of trace elements in Group IIIA-VA is known to activate aluminium anodically in chloride environment. The purpose of this paper is to investigate the surface segregation of trace element In by heat treatment and resulting surface activation. Model binary AlIn alloys, containing 20 and 1000 ppm by weight of In, were characterized after heat treatment at various temperatures by use of glow discharge optical emission spectroscopy, electron microscopy and electrochemical polarization. Heat treatment for 1 h at 300 {sup o}C gave significant segregation of discrete In particles (thermal segregation), which activated the surface. Indium in solid solution with aluminium, obtained by 1 h heat treatment at 600 {sup o}C, also activated by surface segregation of In on alloy containing 1000 ppm In, resulting from the selective dissolution of the aluminium component during anodic oxidation (anodic segregation). The effect of anodic segregation was reduced by decreasing indium concentration in solid solution; it had negligible effect at the 20 ppm level. The segregated particles were thought to form a liquid phase alloy with aluminium during anodic polarization, which in turn, together with the chloride in the solution destabilized the oxide.

  1. FLZ Attenuates α-Synuclein-Induced Neurotoxicity by Activating Heat Shock Protein 70.

    Science.gov (United States)

    Bao, Xiu-Qi; Wang, Xiao-Liang; Zhang, Dan

    2017-01-01

    Parkinson's disease (PD) is the second most prevalent neurodegenerative disease. The pathology of PD is caused by progressive degeneration of dopaminergic neurons and is characterized by the presence of intracellular inclusions known as Lewy bodies, composed mainly of α-synuclein. Heat shock proteins (HSPs) are crucial in protein quality control in cells. HSP70 in particular prevents the aggregation of protein aggregation, such as α-synuclein, providing a degree of protection against PD. The compound FLZ has been shown to protect several PD models in previous studies and was reported as an HSP inducer to protect against MPP + -induced neurotoxicity, but the mechanism remains unclear. In this study, we investigated the effects of FLZ-mediated HSP70 induction in α-synuclein transgenic mice and cells. FLZ treatment alleviated motor dysfunction and improved dopaminergic neuronal function in α-synuclein transgenic mice. HSP70 protein expression and transcriptional activity were increased by FLZ treatment, eliciting a reduction of α-synuclein aggregation and associated toxicity. The inhibition of HSP70 by quercetin or HSP70 siRNA markedly attenuated the neuroprotective effects of FLZ, confirming that FLZ exerted a neuroprotective effect through HSP70. We revealed that FLZ directly bound to and increased the expression of Hip, a cochaperone of HSP70, which in turn enhanced HSP70 activity. In conclusion, we defined a critical role for HSP70 and its cochaperones activated by FLZ in preventing neurodegeneration and proposed that targeting the HSP70 system may represent a potential therapy for α-synuclein-related diseases, such as PD.

  2. ATF1 Modulates the Heat Shock Response by Regulating the Stress-Inducible Heat Shock Factor 1 Transcription Complex

    Science.gov (United States)

    Takii, Ryosuke; Fujimoto, Mitsuaki; Tan, Ke; Takaki, Eiichi; Hayashida, Naoki; Nakato, Ryuichiro; Shirahige, Katsuhiko

    2014-01-01

    The heat shock response is an evolutionally conserved adaptive response to high temperatures that controls proteostasis capacity and is regulated mainly by an ancient heat shock factor (HSF). However, the regulation of target genes by the stress-inducible HSF1 transcription complex has not yet been examined in detail in mammalian cells. In the present study, we demonstrated that HSF1 interacted with members of the ATF1/CREB family involved in metabolic homeostasis and recruited them on the HSP70 promoter in response to heat shock. The HSF1 transcription complex, including the chromatin-remodeling factor BRG1 and lysine acetyltransferases p300 and CREB-binding protein (CBP), was formed in a manner that was dependent on the phosphorylation of ATF1. ATF1-BRG1 promoted the establishment of an active chromatin state and HSP70 expression during heat shock, whereas ATF1-p300/CBP accelerated the shutdown of HSF1 DNA-binding activity during recovery from acute stress, possibly through the acetylation of HSF1. Furthermore, ATF1 markedly affected the resistance to heat shock. These results revealed the unanticipated complexity of the primitive heat shock response mechanism, which is connected to metabolic adaptation. PMID:25312646

  3. The local heat treatment equipment and technology of the pipelines welded joints

    International Nuclear Information System (INIS)

    Korol'kov, P.M.

    1998-01-01

    The principal methods and equipment for local treatment of the pipe-lines weld joints in different industry branches is described. Recommendations about heat treatment equipment and technology application are given

  4. Effect of heat treatments on machinability of gold alloy with age-hardenability at intraoral temperature.

    Science.gov (United States)

    Watanabe, I; Baba, N; Watanabe, E; Atsuta, M; Okabe, T

    2004-01-01

    This study investigated the effect of heat treatment on the machinability of heat-treated cast gold alloy with age-hardenability at intraoral temperature using a handpiece engine with SiC wheels and an air-turbine handpiece with carbide burs and diamond points. Cast gold alloy specimens underwent various heat treatments [As-cast (AC); Solution treatment (ST); High-temperature aging (HA), Intraoral aging (IA)] before machinability testing. The machinability test was conducted at a constant machining force of 0.784N. The three circumferential speeds used for the handpiece engine were 500, 1,000 and 1,500 m/min. The machinability index (M-index) was determined as the amount of metal removed by machining (volume loss, mm(3)). The results were analyzed by ANOVA and Scheffé's test. When an air-turbine handpiece was used, there was no difference in the M-index of the gold alloy among the heat treatments. The air-turbine carbide burs showed significantly (pmachinability of the gold alloy using the air-turbine handpiece. The heat treatments had a small effect on the M-index of the gold alloy machined with a SiC wheel for a handpiece engine.

  5. Study of the Al-Si-X system by different cooling rates and heat treatment

    Directory of Open Access Journals (Sweden)

    Miguel Angel Suarez

    2012-10-01

    Full Text Available The solidification behavior of the Al-12.6% Si (A1, the hypereutectic Al-20%Si (A2 and the Al-20%Si-1.5% Fe-0.5%Mn (A3 (in wt. (% alloys, at different cooling rates is reported and discussed. The cooling rates ranged between 0.93 °C/s and 190 °C/s when cast in sand and copper wedge-shaped molds, respectively. A spheroidization heat treatment was carried out to the alloys in the as-cast condition at 540 °C for 11 hours and quench in water with a subsequent heat treatment at 170 °C for 5 hours with the purpose of improving the mechanical properties. The samples were characterized by optical microscopy, scanning electron microscopy and mechanically by tensile test, in order to evaluate the response of the heat treatment on the different starting microstructures and mechanical properties. It was found that alloys cooled at rates greater than 10.8 °C/s had a smaller particle size and better distribution, also showed a greater response to spheroidization heat treatment of all silicon (Si phases. The spheroidization heat treatment caused an increase in the ultimate tensile stress (UTS and elongation when compared with the alloys in the as-cast condition. The highest UTS value of 174 MPa was obtained for the (A1 alloy.

  6. Small-angle X-ray scattering studies of metastable intermediates of beta-lactoglobulin isolated after heat-induced aggregation

    DEFF Research Database (Denmark)

    Carrotta, R.; Arleth, L.; Pedersen, J.S.

    2003-01-01

    Small-angle x-ray scattering was used for studying intermediate species, isolated after heat-induced aggregation of the A variant of bovine P-lactoglobulin. The intermediates were separated in two fractions, the heated metastable dimer and heated metastable oligomers larger than the dimer. The pa...

  7. Heat Tolerance Induction of the Indian Meal Moth (Lepidoptera: Pyralidae) Is Accompanied by Upregulation of Heat Shock Proteins and Polyols.

    Science.gov (United States)

    Kim, Minhyun; Lee, Seunghee; Chun, Yong Shik; Na, Jahyun; Kwon, Hyeok; Kim, Wook; Kim, Yonggyun

    2017-08-01

    The Indian meal moth, Plodia interpunctella, causes massive damage to stored grains and processed foods. Heat treatment has been widely used to control insect pests infesting stored grains. However, heat treatment may result in unsatisfactory control owing to heat tolerance of target insects. This study quantified the heat tolerance and analyzed its induction in P. interpunctella. Susceptibility of P. interpunctella to different high temperatures was assessed in all developmental stages. Heat treatment at 44 °C for 1 h caused significant mortalities to all developmental stages, with late-instar larvae exhibiting the highest tolerance. However, the survivorship to heat treatment was significantly increased by pre-exposure to 37 °C for 30 min. The induction of heat tolerance was accompanied by upregulation of two heat shock proteins of Hsc70 and Hsp90. Trehalose and glycerol concentrations in the hemolymph also increased after pre-exposure to 37 °C for 30 min. RNA interference (RNAi) by specific double-stranded RNAs effectively suppressed the inducible expressions of both Hsc70 and Hsp90 in response to 37 °C for 30 min. Either RNAi of Hsc70 or Hsp90 significantly impaired the heat tolerance induction of P. interpunctella. These results suggest that the induction of heat tolerance in P. interpunctella involves the upregulation of these heat shock proteins and hemolymph polyol levels. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Alkali-heat treatment of a low modulus biomedical Ti-27Nb alloy

    International Nuclear Information System (INIS)

    Zhou, Y; Wang, Y B; Zhang, E W; Cheng, Y; Xiong, X L; Zheng, Y F; Wei, S C

    2009-01-01

    This study focuses on the surface modification of a near β-type Ti-27 wt.% Nb alloy by alkali-heat treatment. The influence of alkali concentration, alkali-treated time and alkali-treated temperature on the microstructure and constitutional phases of the modified surface is investigated by SEM, XRD and ICP. Immersion experiments in a simulated body fluid (SBF) were carried out to examine the Ca-P phase forming ability of the modified surfaces. The SEM observation and XRD analysis revealed that a sodium titanate layer is formed after alkali-heat treatment. The morphology and Ca-P phase forming of the layer are greatly affected by the surface roughness of the samples, the alkali concentration, the alkali-treated time and alkali-treated temperature. The results of SBF immersion, which are obtained by ICP analysis, indicate that the activated sodium titanate layer prepared by alkali-heat treatment is beneficial to further improving the biocompatibility of the Ti-27 wt.% Nb alloy.

  9. Effects of Heat Treatment on SiC-SiC Ceramic Matrix Composites

    Science.gov (United States)

    Knauf, Michael W.

    Residual stresses resulting from the manufacturing process found within a silicon carbide/silicon carbide (SiC/SiC) ceramic matrix composite were thoroughly investigated through the use of high-energy X-ray diffraction and Raman microspectroscopy. The material system studied was a Rolls-Royce composite produced with Hi-Nicalon fibers woven into a five harness satin weave, coated with boron nitride and silicon carbide interphases, and subsequently infiltrated with silicon carbide particles and a silicon matrix. Constituent stress states were measured before, during, and after heat treatments ranging from 900 °C to 1300 °C for varying times between one and sixty minutes. Stress determination methods developed through these analyses can be utilized in the development of ceramic matrix composites and other materials employing boron-doped silicon. X-ray diffraction experiments were performed at the Argonne National Laboratory Advanced Photon Source to investigate the evolution of constituent stresses through heat treatment, and determine how stress states are affected at high temperature through in situ measurements during heat treatments up to 1250 °C for 30 minutes. Silicon carbide particles in the as-received condition exhibited a nearly isotropic stress state with average tensile stresses of approximately 300 MPa. The silicon matrix exhibited a complimentary average compressive stress of approximately 300 MPa. Strong X-ray diffraction evidence is presented demonstrating solid state boron diffusion and increased boron solubility found in silicon throughout heat treatment. While the constituent stress states did evolve through the heat treatment cycles, including approaching nearly stress-free conditions at temperatures close to the manufacturing temperature, no permanent relaxation of stress was observed. Raman spectroscopy was utilized to investigate stresses found within silicon carbide particles embedded within the matrix and the silicon matrix as an alternate

  10. Laser heat treatment of welds for various stainless steels

    Science.gov (United States)

    Dontu, O.; Ganatsios, S.; Alexandrescu, N.; Predescu, C.

    2008-03-01

    The paper presents a study concerning the post - weld heat treatment of a duplex stainless steel. Welded joint samples were surface - treated using the same laser source adopted during welding in order to counterbalance the excess of ferrite formed in the welding process.

  11. A previously undescribed organic residue sheds light on heat treatment in the Middle Stone Age.

    Science.gov (United States)

    Schmidt, Patrick; Porraz, Guillaume; Bellot-Gurlet, Ludovic; February, Edmund; Ligouis, Bertrand; Paris, Céline; Texier, Pierre-Jean; Parkington, John E; Miller, Christopher E; Nickel, Klaus G; Conard, Nicholas J

    2015-08-01

    South Africa has in recent years gained increasing importance for our understanding of the evolution of 'modern human behaviour' during the Middle Stone Age (MSA). A key element in the suite of behaviours linked with modern humans is heat treatment of materials such as ochre for ritual purposes and stone prior to tool production. Until now, there has been no direct archaeological evidence for the exact procedure used in the heat treatment of silcrete. Through the analysis of heat-treated artefacts from the Howiesons Poort of Diepkloof Rock Shelter, we identified a hitherto unknown type of organic residue - a tempering-residue - that sheds light on the processes used for heat treatment in the MSA. This black film on the silcrete surface is an organic tar that contains microscopic fragments of charcoal and formed as a residue during the direct contact of the artefacts with hot embers of green wood. Our results suggest that heat treatment of silcrete was conducted directly using an open fire, similar to those likely used for cooking. These findings add to the discussion about the complexity of MSA behaviour and appear to contradict previous studies that had suggested that heat treatment of silcrete was a complex (i.e., requiring a large number of steps for its realization) and resource-consuming procedure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Effect of heat treatment on brewer's yeast fermentation activity

    OpenAIRE

    Kharandiuk, Tetiana; Kosiv, Ruslana; Palianytsia, Liubov; Berezovska, Natalia

    2015-01-01

    The influence of temperature treatment of brewer's yeast strain Saflager W-34/70 at temperatures of -17, 20, 25, 30, 35, 40 °C on their fermentative activity was studied. It was established that the freezing of yeast leads to a decrease of fermentation activity in directly proportional to the duration way. Fermentative activity of yeast samples can be increased by 20-24% by heat treatment at 35 °C during 15-30 minutes.

  13. Effect of intercritical heat treatment on mechanical properties of reinforcing steel bars

    International Nuclear Information System (INIS)

    Abro, M.I.; Memon, R.A.; Soomro, I.A.; Aftab, U.

    2017-01-01

    Intercritical heat treatments attempts were made to enhance the mechanical properties of reinforcing steel bars milled from scrap metal. For this, two grades of steel bars were obtained from different steel mills and their mechanical properties that include hardness, ultimate tensile strength, and percent elongation before and after intercritical heat treatment were determined. Results indicated that 25.5 and 17.6%, improvements in UTS (Ultimate Tensile Strength) and 18.8 and 14.3% improvement in percent elongation in two grades of reinforcing steel samples containing 0.17 and 0.24% carbon respectively was achieved while heating at 750 degree C for 2h. Appreciable improvement in the mechanical properties was noted due to birth of sufficient quantity of martensite along with ferrite. (author)

  14. The Effect of Heat Treatment on the Sensitized Corrosion of the 5383-H116 Al-Mg Alloy

    Directory of Open Access Journals (Sweden)

    Ying-Kai Lin

    2017-03-01

    Full Text Available In this study, the effects of heat treatment and sensitized corrosion on the 5383-H116 Al-Mg alloy were investigated for temperatures ranging from 100 to 450 °C. The results show that the heat treatment temperature is the main factor that causes changes to the microstructure and mechanical strength of the 5383-H116 Al-Mg alloy, inducing β-phase (Al3Mg2 precipitation in the form of a continuous layer along the grain boundaries. Intergranular corrosion was caused by the β-phase of the grain boundary precipitation, and the corrosion susceptibility of the recrystallized structure was significantly higher than the corrosion susceptibility of the recovered structure. According to the conductivity values detected, β-phase precipitation can enhance the 5383-H116 Al-Mg alloy conductivity, with the response due to structural dislocation density being higher than that due to the recrystallized structure. As such, the β-phase precipitation after sensitization is more significant than the β-phase precipitation prior to the sensitization, such that after sensitization, the conductivity rises to a significantly higher level than that exhibited by the recrystallization structure.

  15. Influence of Heat Treatment on Abrasive Wear Resistance of Silumin Matrix Composite Castings

    Directory of Open Access Journals (Sweden)

    Gawdzińska K.

    2016-03-01

    Full Text Available The authors attempted at examining the effect of heat treatment on abrasive wear resistance of metal composite castings. Metal matrix composites were made by infiltrating preforms created from unordered short fibers (graphite or silumin with liquid aluminium alloy AlSi12(b. Thus prepared composites were subject to solution heat treatment at a temperature of 520°C for four hours, then aging at a temperature of 220°C for four hours. Abrasion resistance of the material was tested before and after thermal treatment.

  16. Protein denaturation and functional properties of Lenient Steam Injection heat treated whey protein concentrate

    DEFF Research Database (Denmark)

    Dickow, Jonatan Ahrens; Kaufmann, Niels; Wiking, Lars

    2012-01-01

    Whey protein concentrate (WPC) was heat treated by use of the novel heat treatment method of Lenient Steam Injection (LSI) to elucidate new functional properties in relation to heat-induced gelation of heat treated WPC. Denaturation was measured by both DSC and FPLC, and the results of the two...... methods were highly correlated. Temperatures of up to 90 °C were applicable using LSI, whereas only 68 °C could be reached by plate heat exchange before coagulation/fouling. Denaturation of whey proteins increased with increasing heat treatment temperature up to a degree of 30–35% denaturation at 90 °C...

  17. Evaluation of dry heat treatment of soft wheat flour for the production of high ratio cakes.

    Science.gov (United States)

    Keppler, S; Bakalis, S; Leadley, C E; Sahi, S S; Fryer, P J

    2018-05-01

    An accurate method to heat treat flour samples has been used to quantify the effects of heat treatment on flour functionality. A variety of analytical methods has been used such as oscillatory rheology, rheomixer, solvent retention capacity tests, and Rapid Visco Analysis (RVA) in water and in aqueous solutions of sucrose, lactic acid, and sodium carbonate. This work supports the hypothesis that heat treatment facilitates the swelling of starch granules at elevated temperature. Results furthermore indicated improved swelling ability and increased interactions of flour polymers (in particular arabinoxylans) of heat treated flour at ambient conditions. The significant denaturation of the proteins was indicated by a lack of gluten network formation after severe heat treatments as shown by rheomixer traces. Results of these analyses were used to develop a possible cake flour specification. A method was developed using response surfaces of heat treated flour samples in the RVA using i) water and ii) 50% sucrose solution. This can uniquely characterise the heat treatment a flour sample has received and to establish a cake flour specification. This approach might be useful for the characterisation of processed samples, rather than by baking cakes. Hence, it may no longer be needed to bake a cake after flour heat treatment to assess the suitability of the flour for high ratio cake production, but 2 types of RVA tests suffice. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Analysis of Thermal Stresses and Strains Developing during the Heat Treatment of Windmill Shaft

    Directory of Open Access Journals (Sweden)

    Cebo-Rudnicka A.

    2017-06-01

    Full Text Available In the paper the results of evaluation of the temperature and stress fields during four cycles of the heat treatment process of the windmill shaft has been presented. The temperature field has been calculated from the solution to the heat conduction equation over the whole heat treatment cycles of the windmill shaft. To calculate the stress field an incremental method has been used. The relations between stresses and strains have been described by Prandtl-Reuss equation for the elastic-plastic body. In order to determine the changes in the temperature and stress fields during heat treatment of the windmill shaft self-developed software utilizing the Finite Element Method has been used. This software can also be used to calculate temperature changes and stress field in ingots and other axially symmetric products. In the mathematical model of heating and cooling of the shaft maximum values of the strains have been determined, which allowed to avoid the crack formation. The critical values of strains have been determined by using modified Rice and Tracy criterion.

  19. Effect of prolonged isothermal heat treatment on the mechanical behavior of advanced NANOBAIN steel

    Science.gov (United States)

    Avishan, Behzad

    2017-09-01

    The microstructural evolution and consequent changes in strength and ductility of advanced NANOBAIN steel during prolonged isothermal heat-treatment stages were investigated. The microstructure and mechanical properties of nanostructured bainite were not expected to be influenced by extending the heat-treatment time beyond the optimum value because of the autotempering phenomenon and high tempering resistance. However, experimental results indicated that the microstructure was thermodynamically unstable and that prolonged austempering resulted in carbon depletion from high-carbon retained austenite and carbide precipitations. Therefore, austenite became thermally less stable and partially transformed into martensite during cooling to room temperature. Prolonged austempering did not lead to the typical tempering sequence of bainite, and the sizes of the microstructural constituents were independent of the extended heat-treatment times. This independence, in turn, resulted in almost constant ultimate tensile strength values. However, microstructural variations enhanced the yield strength and the hardness of the material at extended isothermal heat-treatment stages. Finally, although microstructural changes decreased the total elongation and impact toughness, considerable combinations of mechanical properties could still be achieved.

  20. Effects of heat treatments and neutron irradiation on the physical and mechanical properties of copper alloys at 100 deg. C

    International Nuclear Information System (INIS)

    Singh, B.N.; Eldrup, M.; Toft, P.; Edwards, D.J.

    1998-05-01

    The final irradiation experiment in a series of screening experiments aimed at investigating the effects of bonding and bakeout thermal cycles on irradiated copper alloys is described herein. Tensile specimens of CuCrZr and CuNiBe alloys were given various heat treatments corresponding to solution anneal, prime-ageing and bonding thermal treatment. Additional specimens were reaged and given a reactor bakeout treatment at 350 deg. C for 100 h. GlidCop TM CuAl-15 (previously referred to as CuAl-25) was given a heat treatment corresponding to a bonding thermal cycle only. Specimens were neutron irradiated at 100 deg. C to a dose level of ∼0.3 dpa. Post-irradiation tensile tests at (100 deg. C), electrical resistivity measurements (at 23 deg. C), and microstructural examinations were performed. The post-irradiation tests at 100 deg. C revealed that the greatest loss of ductility occurred in the CuCrZr alloys irradiated at 100 deg. C, irrespective of the pre-irradiation heat treatment, with the uniform elongation dropping to levels of less than 1.5%. The yield and ultimate strengths for all of the individual heat treated samples increased substantially after irradiation. The same trend was observed for the CuNiBe alloys, which exhibited much higher uniform elongation and strength after irradiation than that observed in the case of CuCrZr alloys. In both alloys irradiation-induced precipitation lead to a large increase in the strength of the solution annealed specimens with a noticeable decrease in uniform elongation. The CuAl-25 alloy also experienced an increase in the overall strength of the alloy after irradiation, accompanied by approximately a 50% decrease in the uniform and total elongation. The additional bakeout treatments given to the CuCrZr and CuNiBe before irradiation served to increase the strength, but in terms of the ductility no improvement or degradation resulted from the additional thermal exposure

  1. Heat-processed ginseng saponin ameliorates the adenine-induced renal failure in rats

    OpenAIRE

    Kim, Eun Jin; Oh, Hyun-A; Choi, Hyuck Jai; Park, Jeong Hill; Kim, Dong-Hyun; Kim, Nam Jae

    2013-01-01

    To evaluate the effect of the saponin of heat-processed ginseng (Sun ginseng, SG), we investigated the protective effect of SG total saponin fraction against adenine-induced chronic renal failure in rats. SG saponin significantly decreased the levels of urea nitrogen and creatinine in the serum, but increased the urinary excretion of urea nitrogen and creatinine, indicating an improvement of renal function. SG saponin also inhibited adenine-induced kidney hypertrophy and edema. SG saponin red...

  2. Susceptibility of Plodia interpunctella (Lepidoptera: Pyralidae) developmental stages to high temperatures used during structural heat treatments.

    Science.gov (United States)

    Mahroof, R; Subramanyam, B

    2006-12-01

    Heating the ambient air of a whole, or a portion of a food-processing facility to 50 to 60 degrees C and maintaining these elevated temperatures for 24 to 36 h, is an old technology, referred to as heat treatment. There is renewed interest in adopting heat treatments around the world as a viable insect control alternative to fumigation with methyl bromide. There is limited published information on responses of the Indian meal moth, Plodia interpunctella (Hübner), exposed to elevated temperatures typically used during heat treatments. Time-mortality relationships were determined for eggs, fifth-instars (wandering-phase larvae), pupae, and adults of P. interpunctella exposed to five constant temperatures between 44 and 52 degrees C. Mortality of each stage increased with increasing temperature and exposure time. In general, fifth-instars were the most heat-tolerant stage at all temperatures tested. Exposure for a minimum of 34 min at 50 degrees C was required to kill 99% of the fifth-instars. It is proposed that heat treatments aimed at controlling fifth-instars should be able to control all other stages of P. interpunctella.

  3. Simple approach to carboxyl-rich materials through low-temperature heat treatment of hydrothermal carbon in air

    Energy Technology Data Exchange (ETDEWEB)

    Chen Zhen; Ma Lijian; Li Shuqiong; Geng Junxia; Song Qiang; Liu Jun; Wang Chunli; Wang Hang; Li Juan [College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics and Technology (Sichuan University), Ministry of Education, Chengdu 610064 (China); Qin Zhi [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Li Shoujian, E-mail: sjli000616@scu.edu.cn [College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics and Technology (Sichuan University), Ministry of Education, Chengdu 610064 (China)

    2011-08-01

    It was found that a large number of oxygen-containing functional groups (OFGs) could be created on the surface of hydrothermal carbon (HTC) by simply heating at lower temperature in air during the course of our preliminary experiments which focused on oxidation pre-treatment of pristine HTC for the purpose of grafting functionalization. Especially carboxyl groups on HTC would increase significantly, from 0.53 to 3.70 mmol/g after heat treatment at 300 deg. C. So, effects of heat-treatment on the OFGs on the carbon microsphere were deeply studied to confirm and explain the findings. Experiments involving different materials (HTC, activated carbon and glucose) were performed under varying conditions (heating temperature and time, in air or in Ar atmosphere). A reaction mechanism for newly generating carboxyl groups on HTC surface during heat-treatment process was supposed based on the results from the sample characterization using Boehm titrations, infrared spectra, X-ray photoelectron spectroscopy, energy dispersive spectrometry and elemental analysis. In addition, the as heat-treated product has excellent sorption capability for Pb{sup 2+} and Cd{sup 2+} ions.

  4. Influence of heat treatment temperature on bonding and oxidation ...

    Indian Academy of Sciences (India)

    The effects of heat treatment temperature on the morphology, composition, chemical bonds, oxidation resistance and compressive strength of diamond particles coated with TiO2 films were characterized through scanning electron microscopy, Fourier transform infrared, Raman spectroscopy, X-ray diffraction analysis, X-ray ...

  5. Application of microjet in heat treatment of aluminium bronzes

    Directory of Open Access Journals (Sweden)

    Z. Górny

    2011-04-01

    Full Text Available Mechanical properties of a CuAl10Fe4Ni4 bronze subjected to solution heat treatment and toughening were examined. In solution heattreatment, a microjet was used to raise the cooling rate. A slight increase of mechanical properties was observed.

  6. Effect of homogenization and heat treatment on the behavior of protein and fat globules during gastric digestion of milk.

    Science.gov (United States)

    Ye, Aiqian; Cui, Jian; Dalgleish, Douglas; Singh, Harjinder

    2017-01-01

    The effects of homogenization and heat treatment on the formation and the breakdown of clots during gastric digestion of whole milk were investigated using a human gastric simulator. Homogenization and heat treatment led to formation of coagula with fragmented and crumbled structures compared with the coagulum formed from raw whole milk, but a larger fraction of the protein and more fat globules were incorporated into the coagula induced by action of the milk-clotting enzyme pepsin. The fat globules in the whole milk appeared to be embedded in the clots as they formed. After formation of the clot, the greater numbers of pores in the structures of the clots formed with homogenized milk and heated whole milk led to greater rates of protein hydrolysis by pepsin, which resulted in faster release of fat globules from the clots into the digesta. Coalescence of fat globules occurred both in the digesta and within the protein clots no matter whether they were in homogenized or heated milk samples. The formation of clots with different structures and hence the changes in the rates of protein hydrolysis and the release of milk fat into the digesta in the stomach provide important information for understanding the gastric emptying of milk and the potential to use this knowledge to manipulate the bioavailability of fat and other fat-soluble nutrients in dairy products. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  7. Biologically Synthesized Gold Nanoparticles Ameliorate Cold and Heat Stress-Induced Oxidative Stress in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Xi-Feng Zhang

    2016-06-01

    Full Text Available Due to their unique physical, chemical, and optical properties, gold nanoparticles (AuNPs have recently attracted much interest in the field of nanomedicine, especially in the areas of cancer diagnosis and photothermal therapy. Because of the enormous potential of these nanoparticles, various physical, chemical, and biological methods have been adopted for their synthesis. Synthetic antioxidants are dangerous to human health. Thus, the search for effective, nontoxic natural compounds with effective antioxidative properties is essential. Although AuNPs have been studied for use in various biological applications, exploration of AuNPs as antioxidants capable of inhibiting oxidative stress induced by heat and cold stress is still warranted. Therefore, one goal of our study was to produce biocompatible AuNPs using biological methods that are simple, nontoxic, biocompatible, and environmentally friendly. Next, we aimed to assess the antioxidative effect of AuNPs against oxidative stress induced by cold and heat in Escherichia coli, which is a suitable model for stress responses involving AuNPs. The response of aerobically grown E. coli cells to cold and heat stress was found to be similar to the oxidative stress response. Upon exposure to cold and heat stress, the viability and metabolic activity of E. coli was significantly reduced compared to the control. In addition, levels of reactive oxygen species (ROS and malondialdehyde (MDA and leakage of proteins and sugars were significantly elevated, and the levels of lactate dehydrogenase activity (LDH and adenosine triphosphate (ATP significantly lowered compared to in the control. Concomitantly, AuNPs ameliorated cold and heat-induced oxidative stress responses by increasing the expression of antioxidants, including glutathione (GSH, glutathione S-transferase (GST, super oxide dismutase (SOD, and catalase (CAT. These consistent physiology and biochemical data suggest that AuNPs can ameliorate cold and

  8. The Microstructure And Mechanical Properties Of The AlSi17Cu5 Alloy After Heat Treatment

    Directory of Open Access Journals (Sweden)

    Piątkowski J.

    2015-09-01

    Full Text Available In the paper results of the microstructure and mechanical properties (HB, Rm and R0,2 of AlSi17Cu5 alloy, subjected by solution heat treatment (500ºC/6h/woda and aging (200ºC/16h/piec are presented. In next step the alloy was modified and heated significantly above the Tliq temperature (separately and together. It was found that the increase in the strength properties of the tested alloy after heat treatment compared to alloys without solution heat treatment and aging was due to precipitation hardening. The applied aging treatment of ingots (preceded by solution heat treatment, causes not only increase in concentration in α(Al solid solution, but also a favorable change of the primary Si crystals morphology. During stereological measurements significant size reduction and change in the morphology of hypereutectic silicon crystals ware found. This effects can be further enhanced by overheating the alloy to a temperature of 920ºC and rapid cooling before casting of the alloy.

  9. The influence of distal-end heat treatment on deflection of nickel-titanium archwire

    Directory of Open Access Journals (Sweden)

    Marcelo Faria da Silva

    2016-02-01

    Full Text Available Objective: The aim of this in vitro study was to evaluate the deflection-force behavior of nickel-titanium (NiTi orthodontic wires adjacent to the portion submitted to heat treatment. Material and Methods: A total of 106 segments of NiTi wires (0.019 x 0.025-in and heat-activated NiTi wires (0.016 x 0.022-in from four commercial brands were tested. The segments were obtained from 80 archwires. For the experimental group, the distal portion of each segmented archwire was subjected to heat treatment (n = 40, while the other distal portion of the same archwire was used as a heating-free control group (n = 40. Deflection tests were performed in a temperature-controlled universal testing machine. Unpaired Student's t-tests were applied to determine if there were differences between the experimental and control groups for each commercial brand and size of wire. Statistical significance was set at p < 0.05. Results: There were no statistically significant differences between the tested groups with the same size and brand of wire. Conclusions: Heat treatment applied to the distal ends of rectangular NiTi archwires does not permanently change the elastic properties of the adjacent portions.

  10. Induction of Heat Shock Protein 70 Ameliorates Ultraviolet-Induced Photokeratitis in Mice

    Directory of Open Access Journals (Sweden)

    Yukihiro Horie

    2013-01-01

    Full Text Available Acute ultraviolet (UV B exposure causes photokeratitis and induces apoptosis in corneal cells. Geranylgeranylacetone (GGA is an acyclic polyisoprenoid that induces expression of heat shock protein (HSP70, a soluble intracellular chaperone protein expressed in various tissues, protecting cells against stress conditions. We examined whether induction of HSP70 has therapeutic effects on UV-photokeratitis in mice. C57 BL/6 mice were divided into four groups, GGA-treated (500 mg/kg/mouse and UVB-exposed (400 mJ/cm2, GGA-untreated UVB-exposed (400 mJ/cm2, GGA-treated (500 mg/kg/mouse but not exposed and naive controls. Eyeballs were collected 24 h after irradiation, and corneas were stained with hematoxylin and eosin (H&E and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL. HSP70, reactive oxygen species (ROS production, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB and protein kinase B (Akt expression were also evaluated. Irradiated corneal epithelium was significantly thicker in the eyes of mice treated with GGA compared with those given the vehicle alone (p < 0.01. Significantly fewer TUNEL-positive cells were observed in the eyes of GGA-treated mice than controls after irradiation (p < 0.01. Corneal HSP70 levels were significantly elevated in corneas of mice treated with GGA (p < 0.05. ROS signal was not affected by GGA. NF-κB activation was reduced but phospho-(Ser/Ther Akt substrate expression was increased in corneas after irradiation when treated with GGA. GGA-treatment induced HSP70 expression and ameliorated UV-induced corneal damage through the reduced NF-κB activation and possibly increased Akt phosphorilation.

  11. A modified wake oscillator model for predicting vortex induced vibration of heat exchanger tube

    International Nuclear Information System (INIS)

    Feng Zhipeng; Zang Fenggang; Zhang Yixiong; Ye Xianhui

    2014-01-01

    Base on the classical wake oscillator model, a new modified wake oscillator model is proposed, for predicting vortex induced vibration of heat exchanger tube in uniform current. The comparison between the new wake oscillator model and experimental show that the present model can simulate the characteristics of vortex induced vibration of tube. Firstly, the research shows that the coupled fluid-structure dynamical system should be modeled by combined displacement and acceleration mode. Secondly, the empirical parameter in wake oscillator model depends on the material properties of the structure, instead of being a universal constant. Lastly, the results are compared between modified wake oscillator model and fluid-structure interaction numerical model. It shows the present, predicted results are compared to the fluid-structure interaction numerical data. The new modified wake oscillator model can predict the vortex induced heat exchanger tube vibration feasibly. (authors)

  12. Flow induced vibration characteristics in 2X3 bundle critical heat flux experiment

    International Nuclear Information System (INIS)

    Kim, Dae Hun; Chang, Soon Heung

    2005-01-01

    Above a certain heat flux, the liquid can no longer permanently wet the heater surface. This situation leads to an inordinate decrease in the surface heat transfer. This heat flux is commonly referred to as the critical heat flux (CHF). The CHF in nuclear reactors is one of the important thermal hydraulic parameters limiting the available power. Flow induced vibration (FIV) is the vibration caused by a fluid flowing around a body. In the fluid flowing system, FIV occurred by structures and flow condition. Many structures in nuclear power plant system are designed to prevent from structure failure due to FIV. Recently, Hibiki and Ishii (1998) carried out an experimental investigation on the effect of flow-induced vibration (FIV) on two-phase flow structure in vertical tube and reported that the FIV drastically changed the void fraction profiles. The void fraction profiles is one of the important parameter for determining CHF. Therefore, the investigation on the effect of FIV on CHF are needed. The research on FIV characteristics detection during CHF experiment in 2X3 bundle using R-134a has been carried out in KAIST. Using the results new FIV correlation in 2-pahse turbulent flow are suggested after finding out relation between CHF and dynamic pressure fluctuation value

  13. Effect of T6 heat treatment on tensile strength of EN AB-48000 alloy modified with strontium

    Directory of Open Access Journals (Sweden)

    J. Pezda

    2011-07-01

    Full Text Available Among alloys of non-ferrous metals, aluminum alloys have found their broadest application in foundry industry. Silumins are widely used in automotive, aviation and shipbuilding industries; as having specific gravity nearly three times lower than specific gravity of cast iron. The silumins can be characterized by high mechanical properties. To upgrade mechanical properties of a castings made from silumins one makes use of heat treatment, what leads to change of their structure and advantageously affects on mechanical properties of the silumins. In the paper are presented test results concerning effect of dispersion hardening on change of tensile strength of EN AB-48000 silumin modified with strontium. Investigated alloy was melted in electric resistance furnace. Temperature ranges of solution heat treatment and ageing heat treatment were selected on base of curves from ATD method, recorded for refined alloy and for modified alloy. The heat treatment resulted in change of Rm tensile strength, while performed investigations have enabled determination of temperatures and durations of solution heat treatment and ageing heat treatment, which precondition obtainment of the best tensile strength Rm of the investigated alloy.

  14. Heat treatment of TI-6AL-4V produced by lasercusing

    Directory of Open Access Journals (Sweden)

    Becker, Thorsten

    2015-08-01

    Full Text Available LaserCUSING® is a selective laser melting (SLM process that is capable of manufacturing parts by melting powder with heat input from a laser beam. LaserCUSING demonstrates potential for producing the intricate geometries specifically required for biomedical implants and aerospace applications. One main limitation to this form of rapid prototyping is the lack of published studies on the material performance of the resulting material. Studies of the material’s performance are often complicated by dependence on several factors, including starting powder properties, laser parameters, and post-processing heat treatments. This study aims to investigate the mechanical properties of LaserCUSING-produced Ti-6Al-4V and its performance relative to the conventional wrought counterpart. A combination of conventional and LaserCUSING-tailored heat treatments is performed. The resulting microstructures are studied and linked to the properties obtained from hardness tests. The findings highlight that LaserCused Ti-6Al-4V is competitive with traditional materials, provided that optimal parameters are chosen and parts are subject to tailored post-processing. In the as-built condition, LaserCused Ti-6Al-4V displays superior strength and hardness as a result of a martensitic microstructure, and a poorer performance in ductility. However, the material performance can be improved using tailored heat treatments. Careful consideration must be given to suitable post-processing before application in critical components in the aerospace or biomedical industry can occur

  15. Influence of heat treatment on the machinability and corrosion behavior of AZ91 Mg alloy

    Directory of Open Access Journals (Sweden)

    Swetha Chowdary V

    2018-03-01

    Full Text Available In the present study, AZ91 Mg alloy was heat treated at 410 °C for 6, 12 and 24 h to investigate the influence of heat treatment on machinability and corrosion behavior. The effect of soaking time on the amount and distribution of Mg17Al12 (β – phase was analyzed under the optical microscope. Microhardness measurements demonstrated the increased hardness with increased heat treatment soaking time, which can be attributed to the solid solution strengthening. The influence of super saturated α-grains on reducing the cutting force (Fz with respect to increased cutting speed was observed as prominent. The corrosion behavior of the heat treated specimens was studied by conducting electrochemical tests. Surprisingly, corrosion rate of heat treated samples was observed as increased compared with the base material. From the results, it is evident that the machinability of AZ91 Mg alloy can be improved by producing super saturated α-grains through heat treatment but at the cost of losing corrosion resistance. Keywords: AZ91 Mg alloy, Solid solution, Turning, Corrosion, Machinability

  16. The dimethylthiourea-induced attenuation of cisplatin nephrotoxicity is associated with the augmented induction of heat shock proteins

    International Nuclear Information System (INIS)

    Tsuji, Takayuki; Kato, Akihiko; Yasuda, Hideo; Miyaji, Takehiko; Luo, Jinghui; Sakao, Yukitoshi; Ito, Hideaki; Fujigaki, Yoshihide; Hishida, Akira

    2009-01-01

    Dimethylthiourea (DMTU), a potent hydroxyl radical scavenger, affords protection against cisplatin (CDDP)-induced acute renal failure (ARF). Since the suppression of oxidative stress and the enhancement of heat shock proteins (HSPs) are both reported to protect against CDDP-induced renal damage, we tested whether increased HSP expression is involved in the underlying mechanisms of the DMTU-induced renal protection. We examined the effect of DMTU treatment on the expression of HSPs in the kidney until day 5 following a single injection of CDDP (5 mg/kg BW). DMTU significantly inhibited the CDDP-induced increments of serum creatinine, the number of 8-hydroxyl-2'-deoxyguanosine (8-OHdG)- and terminal deoxynucleotidyl transferase nick-end labeling (TUNEL)-positive tubular cells, and tubular damage score (p < 0.05). CDDP significantly increased renal abundances of HO-1, HSP60, HSP72 and HSP90 at days 1, 3, and 5. DMTU significantly augmented only the expression of HSP60 expression mainly in the cytoplasm of the proximal tubular cells at days 1 and 3 in CDDP-induced ARF. DMTU also inhibited the CDDP-induced increment of Bax, a pro-apoptotic protein, in the fraction of organelles/membranes at day 3. The findings suggest that DMTU may afford protection against CDDP-induced ARF, partially through the early induction of cytoplasmic HSP60, thereby preventing the Bax-mediated apoptosis in renal tubular cells

  17. Technoeconomic Optimization of Waste Heat Driven Forward Osmosis for Flue Gas Desulfurization Wastewater Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Gingerich, Daniel B [Carnegie Mellon Univ., Pittsburgh, PA (United States); Bartholomew, Timothy V [Carnegie Mellon Univ., Pittsburgh, PA (United States); Mauter, Meagan S [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2017-06-26

    With the Environmental Protection Agency’s recent Effluent Limitation Guidelines for Steam Electric Generators, power plants are having to install and operate new wastewater technologies. Many plants are evaluating desalination technologies as possible compliance options. However, the desalination technologies under review that can reduce wastewater volume or treat to a zero-liquid discharges standard have a significant energy penalty to the plant. Waste heat, available from the exhaust gas or cooling water from coal-fired power plants, offers an opportunity to drive wastewater treatment using thermal desalination technologies. One such technology is forward osmosis (FO). Forward osmosis utilizes an osmotic pressure gradient to passively pull water from a saline or wastewater stream across a semi-permeable membrane and into a more concentrated draw solution. This diluted draw solution is then fed into a distillation column, where the addition of low temperature waste heat can drive the separation to produce a reconcentrated draw solution and treated water for internal plant reuse. The use of low-temperature waste heat decouples water treatment from electricity production and eliminates the link between reducing water pollution and increasing air emissions from auxiliary electricity generation. In order to evaluate the feasibility of waste heat driven FO, we first build a model of an FO system for flue gas desulfurization (FGD) wastewater treatment at coal-fired power plants. This model includes the FO membrane module, the distillation column for draw solution recovery, and waste heat recovery from the exhaust gas. We then add a costing model to account for capital and operating costs of the forward osmosis system. We use this techno-economic model to optimize waste heat driven FO for the treatment of FGD wastewater. We apply this model to three case studies: the National Energy Technology Laboratory (NETL) 550 MW model coal fired power plant without carbon

  18. Inactivation of T4-phages by heat and γ-irradiation treatment in respect to sludge hygienization

    International Nuclear Information System (INIS)

    Farniok, C.; Turanitz, K.; Stehlik, G.; Meyrath, J.

    1977-04-01

    The effects of γ-irradiation, heat treatment and combined heat/irradiation treatments on T 4 -bacteriophages were studied and evaluated in surviving fractions. To ascertain the extent of inactivation, the formation of plaque was studied in the host organism Escherichia coli K 12 D 10. A 90-minute heat treatment of the bacteriolysat at 55 0 C did not inactivate the bacteriophages, whereas the number of plaque-forming bacteriophages was decreased by 50% at 60 0 C. At 65 0 C a linear correlation of heating period and the logarithm of relative number of phages was observed. After 30 minutes exposure to 70 0 C only few bacteriophages were traced in the plaque test. By inactivation of T 4 -phages after exposure to γ-irradiation a linear correlation of irradiation dose and the logarithm of the relative number of surviving bacteriophages was found. The combined method of heat and irradiation treatments resulted in a synergistic effect. (author)

  19. Modified heat treatment for lower temperature improvement of the mechanical properties of two ultrahigh strength low alloy steels

    Science.gov (United States)

    Tomita, Yoshiyuki; Okabayashi, Kunio

    1985-01-01

    In the previous papers, a new heat treatment for improving the lower temperature mechanical propertise of the ultrahigh strength low alloy steels was suggested by the authors which produces a mixed structure of 25 vol pct lower bainite and 75 vol pct martensite through isothermal transformation at 593 K for a short time followed by water quenching (after austenitization at 1133 K). In this paper, two commercial Japanese ultrahigh strength steels, 0.40 pct C-Ni-Cr-Mo (AISI 4340 type) and 0.40 pct C-Cr-Mo (AISI 4140 type), have been studied to determine the effect of the modified heat treatment, coupled above new heat treatment with γ ⇆ α' repctitive heat treatment, on the mechanical properties from ambient temperature (287 K) to 123 K. The results obtained for various test temperatures have been compared with those for the new heat treatment reported previously and the conventional 1133 K direct water quenching treatment. The incorporation of intermediate four cyclic γ ⇆ α' repctitive heat treatment steps (after the initial austenitization at 1133 K and oil quenching) into the new heat treatment reported previously, as compared with the conventional 1133 K direct water quenching treatment, significantly improved 0.2 pct proof stress as well as notch toughness of the 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel at similar fracture ductility levels from 287 to 123 K. Also, this heat treatment, as compared with the conventional 1133 K direct water quenching treatment, significantly improved both 0.2 pct proof stress and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel with increased fracture ductility at 203 K and above. The microstructure consists of mixed areas of ultrafine grained martensite, within which is the refined blocky, highly dislocated structure, and the second phase lower bainite (about 15 vol pct), which appears in acicular form and partitions prior austenite grains. This newly developed heat treatment makes it possible to modify

  20. Effect of patchouli alcohol on the regulation of heat shock-induced oxidative stress in IEC-6 cells.

    Science.gov (United States)

    Liu, Xiaoxi; Jiang, Linshu; Liu, Fenghua; Chen, Yuping; Xu, Lei; Li, Deyin; Ma, Yunfei; Li, Huanrong; Xu, Jianqin

    2016-08-01

    Purpose Patchouli alcohol (PA) is used to treat gastrointestinal dysfunction. The purpose of this study was to ascertain the function of PA in the regulated process of oxidative stress in rat intestinal epithelial cells (IEC-6). Materials and methods Oxidative stress was stimulated by exposing IEC-6 cells to heat shock (42 °C for 3 h). IEC-6 cells in treatment groups were pretreated with various concentrations of PA (10, 40, and 80 ng/mL) for 3 h before heat shock. Results Heat shock caused damage to the morphology of IEC-6 cells, and increased reactive oxygen species (ROS) level and malondialdehyde (MDA) content. Moreover, mRNA and protein expression by target genes related to oxidative stress in heat shock were also altered. Specifically, the mRNA expression by HSP70, HSP90, GSH-px, NRF2 nd HO-1were all increased, and Nrf2 and Keap1 protein expression were increased after heat shock. However, pretreatment with PA weakened the level of damage to the cellular morphology, and decreased the MDA content caused by heat shock, indicating PA had cytoprotective activities. Pretreatment with PA at high dose significantly increased generation of intracellular ROS. Compared with the heat shock group alone, PA pretreatment significantly decreased the mRNA expression by HSP70, HSP90, SOD, CAT, GSH-px, KEAP1 and HO-1. Furthermore, the high dose of PA significantly increased Nrf2 protein expression, while both the intermediate and high dose of PA significantly increased HO-1 protein expression. Conclusion Heat-shock-induced oxidative stress in IEC-6 cells, and PA could alleviate the Nrf2-Keap1 cellular oxidative stress responses.

  1. Effect of Heat Treatment on the Surface Properties of Activated Carbons

    Directory of Open Access Journals (Sweden)

    Meriem Belhachemi

    2011-01-01

    Full Text Available This work reports the effect of heat treatment on the porosity and surface chemistry of two series of activated carbons prepared from a local agricultural biomass material, date pits, by physical activation with carbon dioxide and steam. Both series samples were oxidized with nitric acid and subsequently heat treated under N2 at 973 K in order to study the effect of these treatments in porosity and surface functional groups of activated carbons. When the activated carbons were heat treated after oxidation the surface area and the pore volume increase for both activated carbons prepared by CO2 and steam activations. However the amount of surface oxygen complexes decreases, the samples keep the most stable oxygen surface groups evolved as CO by temperature-programmed desorption experiments at high temperature. The results show that date pits can be used as precursors to produce activated carbons with a well developed porosity and tailored oxygen surface groups.

  2. Native defect changes in CdS single crystal platelets induced by vacuum heat treatments at temperatures up to 600/sup 0/C

    Energy Technology Data Exchange (ETDEWEB)

    Christmann, M H; Dierssen, G H; Salmon, O N; Taylor, A L; Thom, W H

    1975-12-01

    Physical properties of selected CdS single crystal platelets as-grown and after vacuum heat treatments at temperatures up to 600/sup 0/C were studied using uv excited edge emission, mass spectrometry, electrical resistivity, and electron paramagnetic resonance (EPR). It was found that sulfur leaves the crystal at temperatures as low as 100/sup 0/C creating a depletion layer. The native defect changes were monitored by edge emission studies at 4.2/sup 0/K in combination with etch treatments. The defect structure throughout the crystal is not only dependent upon the temperature and atmosphere of the treatments, but is also strongly dependent upon the cooling rate. (auth)

  3. Heat priming induces trans-generational tolerance to high temperature stress in wheat

    Directory of Open Access Journals (Sweden)

    Xiao eWang

    2016-04-01

    Full Text Available Wheat plants are very sensitive to high temperature stress during grain filling. Effects of heat priming applied to the first generation on tolerance of the successive generation to post-anthesis high temperature stress were investigated. Compared with the progeny of non-heat primed plants (NH, the progeny of heat-primed plants (PH possessed higher grain yield, leaf photosynthesis and activities of antioxidant enzymes and lower cell membrane damage under high temperature stress. In the transcriptome profile, 1430 probes showed obvious difference in expression between PH and NH. These genes were related to signal transduction, transcription, energy, defense, and protein destination and storage, respectively. The gene encoding the lysine-specific histone demethylase 1 (LSD1 which was involved in histone demethylation related to epigenetic modification was up-regulated in the PH compared with NH. The proteome analysis indicated that the proteins involved in photosynthesis, energy production and protein destination and storage were up-regulated in the PH compared with NH. In short, thermos-tolerance was induced through heritable epigenetic alternation and signaling transduction, both processes further triggered prompt modifications of defense related responses in anti-oxidation, transcription, energy production, and protein destination and storage in the progeny of the primed plants under high temperature stress. It was concluded that trans-generation thermo-tolerance was induced by heat priming in the first generation, and this might be an effective measure to cope with severe high-temperature stresses during key growth stages in wheat production.

  4. Activated platelets release sphingosine 1-phosphate and induce hypersensitivity to noxious heat stimuli in vivo

    Directory of Open Access Journals (Sweden)

    Daniela eWeth

    2015-04-01

    Full Text Available At the site of injury activated platelets release various mediators, one of which is sphingosine 1-phosphate (S1P. It was the aim of this study to explore whether activated human platelets had a pronociceptive effect in an in vivo mouse model and whether this effect was based on the release of S1P and subsequent activation of neuronal S1P receptors 1 or 3. Human platelets were prepared in different concentrations (105/µl, 106/µl, 107/µl and assessed in mice with different genetic backgrounds (WT, S1P1fl/fl, SNS-S1P1-/-, S1P3-/-. Intracutaneous injections of activated human platelets induced a significant, dose-dependent hypersensitivity to noxious thermal stimulation. The degree of heat hypersensitivity correlated with the platelet concentration as well as the platelet S1P content and the amount of S1P released upon platelet activation as measured with LC MS/MS. Despite the significant correlations between S1P and platelet count, no difference in paw withdrawal latency (PWL was observed in mice with a global null mutation of the S1P3 receptor or a conditional deletion of the S1P1 receptor in nociceptive primary afferents. Furthermore, neutralisation of S1P with a selective anti-S1P antibody did not abolish platelet induced heat hypersensitivity. Our results suggest that activated platelets release S1P and induce heat hypersensitivity in vivo. However, the platelet induced heat hypersensitivity was caused by mediators other than S1P.

  5. Heart rate variability during exertional heat stress: effects of heat production and treatment.

    Science.gov (United States)

    Flouris, Andreas D; Bravi, Andrea; Wright-Beatty, Heather E; Green, Geoffrey; Seely, Andrew J; Kenny, Glen P

    2014-04-01

    We assessed the efficacy of different treatments (i.e., treatment with ice water immersion vs. natural recovery) and the effect of exercise intensities (i.e., low vs. high) for restoring heart rate variability (HRV) indices during recovery from exertional heat stress (EHS). Nine healthy adults (26 ± 3 years, 174.2 ± 3.8 cm, 74.6 ± 4.3 kg, 17.9 ± 2.8 % body fat, 57 ± 2 mL·kg·(-1) min(-1) peak oxygen uptake) completed four EHS sessions incorporating either walking (4.0-4.5 km·h(-1), 2 % incline) or jogging (~7.0 km·h(-1), 2 % incline) on a treadmill in a hot-dry environment (40 °C, 20-30 % relative humidity) while wearing a non-permeable rain poncho for a slow or fast rate of rectal temperature (T re) increase, respectively. Upon reaching a T re of 39.5 °C, participants recovered until T re returned to 38 °C either passively or with whole-body immersion in 2 °C water. A comprehensive panel of 93 HRV measures were computed from the time, frequency, time-frequency, scale-invariant, entropy and non-linear domains. Exertional heat stress significantly affected 60/93 HRV measures analysed. Analyses during recovery demonstrated that there were no significant differences between HRV measures that had been influenced by EHS at the end of passive recovery vs. whole-body cooling treatment (p > 0.05). Nevertheless, the cooling treatment required statistically significantly less time to reduce T re (p whole-body immersion in 2 °C water results in faster cooling, there were no observed differences in restoration of autonomic heart rate modulation as measured by HRV indices with whole-body cold-water immersion compared to passive recovery in thermoneutral conditions.

  6. Light induced cooling of a heated solid immersed in liquid helium I

    International Nuclear Information System (INIS)

    Lezak, D.; Brodie, L.C.; Semura, J.S.

    1984-01-01

    This chapter investigates the marked enhancement in the transient heat transfer from the heater-thermometer to the liquid helium immediately following the application of a flash of visible light. This ''light effect'' is associated with increased bubble activity, and it is possible that the light induces a rapid nucleation of bubbles in the superheated liquid at or near the heater surface. A summary of the light effect is presented and some potential uses to which this effect could be applied are suggested. Quantification of the light effect and properties of the light effect are discussed. It is determined that the light effect is an additional cooling due to a light induced enhancement of boiling in superheated liquid helium I. The effect could be applied in practical cryogenic engineering and for the acquisition of fundamental knowledge of boiling heat transfer and nucleation in cryogenic liquids

  7. Effect of Annealing Heat Treatment to Characteristics of AlDC8 (Al-Si-Cu) Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Kyung Man; Lee, Sung-Yul; Lee, Myeong Hoon; Jeong, Jae-Hyun [Korea Maritime and Ocean University, Busan (Korea, Republic of); Baek, Tae-Sil [Pohang College, Pohang (Korea, Republic of)

    2015-12-15

    ALDC8 (Al-Si-Cu) alloy has been often corroded with pattern of intergranular corrosion in corrosive environments. Thus, in order to improve its corrosion resistance, the effect of annealing heat treatment to corrosion resistance and hardness was investigated with parameters of heating temperatures such as 100 ℃, 200 ℃, 300 ℃, 400 ℃ and 500 ℃ for 1hr. The hardness was varied with annealing temperature and slightly decreased with annealing heat treatment. However, the relation between annealing temperature and hardness agreed not well each other. Corrosion potential was shifted to noble direction and corrosion current density was also decreased with increasing annealing temperature. Moreover, both AC impedance at 10 mHz and polarization resistance on the cyclic voltammogram curve were also increased with increasing annealing temperature. Furthermore, intergranular corrosion was somewhat observed in non heat treatment as well as annealing temperatures at 100 ℃, 200 ℃ and 300 ℃, while, intergranular corrosion was not nearly observed at annealing temperature of 400 ℃, 500 ℃. Consequently, it is considered that the annealing heat treatment of ALDC8 alloy may be an available method not only to inhibit its intergranular corrosion but also to improve its corrosion resistance.

  8. Oriented heat release in asphalt pavement induced by high-thermal-conductivity rods

    International Nuclear Information System (INIS)

    Du, Yinfei; Wang, Shengyue

    2015-01-01

    In this paper, a new principle of using aligned high-thermal-conductivity rods to enhance the oriented heat conduction in asphalt pavement was proposed. The results showed that the designed structure absorbed more heat during the day. The heat flow in the designed structure presented a non-uniform horizontal distribution. At the depth of 4 cm, the horizontal and vertical heat fluxes through steel rods were thirteen and ten times higher than those through asphalt mixture, respectively. The maximum temperature of the designed structure reduced by 3.6 °C–6.5 °C at the depth of 4 cm. The results of indoor irradiation test showed a trend consistent with those of numerical simulation. After 500 thousand times of standard axis load were applied, the rutting depth of the designed structure reduced by 43.4%. The principle proposed is expected to be used to induce an oriented heat release accumulated in asphalt pavement and reduce pavement temperature and rutting. - Highlights: • Steel rods were inserted in the middle and bottom layers to build thermal channels. • Steel rods absorbed heat from asphalt mixture and rapidly released them to subgrade. • The heat flux through asphalt mixture decreased and pavement temperature reduced.

  9. Laser heat treatment of steel cutting blades for agricultural uses; Tratamiento termico con laser de cuchillas de acero para uso agricola

    Energy Technology Data Exchange (ETDEWEB)

    Muniz, G.; Conde, A.; Fernandez, B. J.; Varela, R.; Garcia, I.; Damborenea, J. de

    2003-07-01

    The present paper focuses on the laser surface treatment of mild steels with different %wt of carbon to be used as cutting blades in agricultural applications. The results are discussed in function of the metallographic study, hardness profiles, wear resistance and corrosion testing. Special attention is paid to the results of the results obtained with the experimental steel with carbon 0.33 %wt because it is a new promising materials specifically developed to be applied in such agricultural uses. Metallographic studies showed three well defined regions: the laser treated zone, where solid state phase transformation occurs, the heat affected zone (HAZ) with partial transformations and finally the bulk metal with the original microstructure. Surface hardness was in all cases higher than the base steel in a depth range 600 {mu}m. Wear resistance is notably improved with laser heat treatment while no detrimental effects were induced in their specific corrosion resistance. (Author) 16 refs.

  10. Effects of sulphuric acid, mechanical scarification and wet heat ...

    African Journals Online (AJOL)

    Effects of different treatment methods on the germination of seeds of Parkia biglobosa (mimosaceae) were carried out. Prior treatment of seeds with sulphuric acid, wet heat and mechanical scarification were found to induce germination of the dormant seeds. These methods could be applied to raise seedlings of the plant for ...

  11. Osteoinduction on acid and heat treated porous Ti metal samples in canine muscle.

    Directory of Open Access Journals (Sweden)

    Toshiyuki Kawai

    Full Text Available Samples of porous Ti metal were subjected to different acid and heat treatments. Ectopic bone formation on specimens embedded in dog muscle was compared with the surface characteristics of the specimen. Treatment of the specimens by H2SO4/HCl and heating at 600 °C produced micrometer-scale roughness with surface layers composed of rutile phase of titanium dioxide. The acid- and heat-treated specimens induced ectopic bone formation within 6 months of implantation. A specimen treated using NaOH followed by HCl acid and then heat treatment produced nanometer-scale surface roughness with a surface layer composed of both rutile and anatase phases of titanium dioxide. These specimens also induced bone formation after 6 months of implantation. Both these specimens featured positive surface charge and good apatite-forming abilities in a simulated body fluid. The amount of the bone induced in the porous structure increased with apatite-forming ability and higher positive surface charge. Untreated porous Ti metal samples showed no bone formation even after 12 months. Specimens that were only heat treated featured a smooth surface composed of rutile. A mixed acid treatment produced specimens with micrometer-scale rough surfaces composed of titanium hydride. Both of them also showed no bone formation after 12 months. The specimens that showed no bone formation also featured almost zero surface charge and no apatite-forming ability. These results indicate that osteoinduction of these porous Ti metal samples is directly related to positive surface charge that facilitates formation of apatite on the metal surfaces in vitro.

  12. Characterization by transmission electron microscopy of a JRQ steel subjected to different heat treatments; Caracterizacion por microscopia electronica de transmision de un acero JRQ sometido a diferentes tratamientos termicos

    Energy Technology Data Exchange (ETDEWEB)

    Moreno G, N.

    2014-07-01

    In this work a study was conducted on the steel Astm A-533, Grade B, Class 1 of reference JRQ, for the purpose of carrying out a study by transmission electron microscopy on the size and distribution of precipitates in steel samples JRQ previously subjected to heat treatments. This because the reactor vessels of the nuclear power plant of Laguna Verde, are made of a steel Astm A-533 Grade B, Class 1. It is known that the neutron radiation causes damage primarily embrittlement in materials that are exposed to it. However, observable damage through mechanical tests result from microstructural defects and atomic, induced by the neutron radiation. In previous studies hardening by precipitation of a JRQ steel (provided by the IAEA) was induced by heat treatments, finding that the conditions of heat treatment that reproduce the hardness and stress mechanical properties of a steel Astm A-533, Grade B, Class 1 irradiated for 8 years to a fluence of 3.5 x 10 {sup 17} neutrons/cm{sup 2} and to a temperature of 290 grades C are achieved with annealing treatments at 550 grades C. In the studied samples it was found that the more hardening phase both the heat treatments as the neutron radiation, is the bainite, being the ferrite practically unchanged. Which it gave the tone to believe that the ferrite is the phase that provides at level macro the mechanical properties in stress, since in the irradiated samples such properties remained unchanged with respect to the non-irradiated material, however changes were observed in material ductility, which may be attributable to the change of hardness in the bainite, which opens a possibility for modeling the micromechanical behavior of this material. (Author)

  13. Viscose liquid heat treatment using plate scraper heat exchanger

    Directory of Open Access Journals (Sweden)

    K. A. Rashkin

    2012-01-01

    Full Text Available The current work analyzes the use of different types of heat exchangers, depending on the technology of production. It is taken the detail analysis of the ways of applicability of various types of heat exchangers, depending on the viscosity of the processed product. It is posed the problem of the analytical determination of the required area of heat exchange with the use of differential equations of heat transfer in a moving liquid media, written in cylindrical coordinates, for symmetrical temperature distribution, without taking in account the energy dissipation.

  14. Circulating antibodies to inducible heat shock protein 70 in patients with uveitis

    NARCIS (Netherlands)

    de Smet, M. D.; Ramadan, A.

    2001-01-01

    Heat shock proteins with molecular weight 70 kDa (hsp70) are highly conserved immunogenic intracellular molecules. There are two main subtypes: one is expressed constitutively (hsc70), while the other is induced under stressful conditions (ihsp70). Using an ELISA directed against recombinant human

  15. Effect of heat treatment on bend stress relaxation of pure tungsten

    International Nuclear Information System (INIS)

    Sasaki, Kenta; Nogami, Shuhei; Fukuda, Makoto; Katakai, Yasuyuki; Hasegawa, Akira

    2013-01-01

    Highlights: • Bend stress relaxation test was performed on the pure tungsten after heat treatment for stress relief. • The BSR ratio of the heat treated specimen was larger than that of the as-received specimen at this temperature region. • Small reduction in the BSR ratio was observed at the temperatures of 500–800 °C. • The BSR ratio of the heat treated specimen decreased significantly at the temperatures of 900–1000 °C. • The BSR ratio decreased significantly in a short time below 0.1 h, and then decreased slowly. -- Abstract: Bend stress relaxation (BSR) tests at temperatures of 500, 600, 800, 900 and 1000 °C for 0.1, 0.5 and 1 h in vacuum were performed on the pure tungsten after heat treatment for stress relief at 900 °C for 1 h. The degree of stress relaxation increased with test temperature. The BSR ratio of the heat treated specimen was larger than that of the as-received specimen at this temperature region. Small reduction in the BSR ratio was observed at the temperatures of 500, 600 and 800 °C. The BSR ratio of the heat treated specimen decreased significantly at the temperatures of 900 and 1000 °C and it was close to that of the as-received specimen. The BSR ratio of the heat treated specimen and the as-received specimen exhibited similar trend of time-evolution. The stress was exponentially relaxed with increasing test time. The BSR ratio decreased significantly in a short time below 0.1 h, and then decreased slowly. Higher activation energy of stress relaxation evaluated by cross-cut method was obtained for the higher temperature

  16. Development of shelf stable, processed, low acid food products using heat-irradiation combination treatments

    International Nuclear Information System (INIS)

    Minnaar, A.

    1998-01-01

    The amount of ionizing irradiation needed to sterilize low acid vegetable and starch products (with and without sauces) commercially impairs their sensorial and nutritive qualities, and use of thermal processes for the same purpose may also have an adverse effect on the product quality. A systematic approach to the establishment of optimized combination parameters was developed for heat-irradiation processing to produce high quality, shelf stable, low acid food products. The effects of selected heat, heat-irradiation combination and irradiation treatments on the quality of shelf stable mushrooms in brine and rice, stored at ambient temperature, were studied. From a quality viewpoint, use of heat-irradiation combination treatments favouring low irradiation dose levels offered a feasible alternative to thermally processed or radappertized mushrooms in brine. However, shelf stable rice produced by heat-irradiation combination treatments offered a feasible alternative only to radappertized rice from the standpoint of quality. The technical requirements for the heat and irradiation processing of a long grain rice cultivar from the United States of America oppose each other directly, thereby reducing the feasibility of using heat-irradiation combination processing to produce shelf stable rice. The stability of starch thickened white sauces was found to be affected severely during high dose irradiation and subsequent storage at ambient temperature. However, use of pea protein isolate as a thickener in white sauces was found to have the potential to maintain the viscosity of sauces for irradiated meat and sauce products throughout processing and storage. (author)

  17. Expression of three sHSP genes involved in heat pretreatment-induced chilling tolerance in banana fruit.

    Science.gov (United States)

    He, Li-hong; Chen, Jian-ye; Kuang, Jian-fei; Lu, Wang-jin

    2012-07-01

    Banana fruit is highly susceptible to chilling injury. In previous research it was shown that heat pretreatment of banana fruit at 38 °C for 3 days before storage at a chilling temperature of 8 °C for 12 days prevented increases in visible chilling injury index, electrolyte leakage and malondialdehyde content and also decreases in lightness and chroma, indicating that heat pretreatment could effectively alleviate chilling injury of banana fruit. However, little is known about the role of small heat shock proteins (sHSPs) in postharvest chilling tolerance of banana fruit. In the present study, three cytosolic sHSP expression profiles in peel and pulp tissues of banana fruit during heat pretreatment and subsequent chilled storage (8 °C) were investigated in relation to heat pretreatment-induced chilling tolerance. Three full-length cDNAs of cytosolic sHSP genes, including two class I sHSP (CI sHSP) and one class II sHSP (CII sHSP) cDNAs, named Ma-CI sHSP1, Ma-CI sHSP2 and Ma-CII sHSP3 respectively, were isolated and characterised from harvested banana fruit. Accumulation of Ma-CI sHSP1 mRNA transcripts in peel and pulp tissues and Ma-CII sHSP3 mRNA transcripts in peel tissue increased during heat pretreatment. Expression of all three Ma-sHSP genes in peel and pulp tissues was induced during subsequent chilled storage. Furthermore, Ma-CI sHSP1 and Ma-CII sHSP3 mRNA transcripts in pulp tissue and Ma-CI sHSP2 mRNA transcripts in peel and pulp tissues were obviously enhanced by heat pretreatment at days 6 and 9 of subsequent chilled storage. These results suggested that heat pretreatment enhanced the expression of Ma-sHSPs, which might be involved in heat pretreatment-induced chilling tolerance of banana fruit. Copyright © 2012 Society of Chemical Industry.

  18. Determination of Heating Value of Estonian Oil Shale by Laser-Induced Breakdown Spectroscopy

    Directory of Open Access Journals (Sweden)

    M. Aints

    2018-01-01

    Full Text Available The laser-induced breakdown spectroscopy (LIBS combined with multivariate regression analysis of measured data were utilised for determination of the heating value and the chemical composition of pellets made from Estonian oil shale samples with different heating values. The study is the first where the oil shale heating value is determined on the basis of LIBS spectra. The method for selecting the optimal number of spectral lines for ordinary multivariate least squares regression model is presented. The correlation coefficient between the heating value predicted by the regression model, and that measured by calorimetric bomb, was R2=0.98. The standard deviation of prediction was 0.24 MJ/kg. Concentrations of oil shale components predicted by the regression model were compared with those measured by ordinary methods.

  19. Comparative study of heat transfer and wetting behaviour of conventional and bioquenchants for industrial heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Peter; Prabhu, K. Narayan [Department of Metallurgical and Materials Engineering, National Institute of Technology Karnataka, Surathkal, P.O. Srinivasnagar 575 025 Mangalore, Karnataka State (India)

    2008-02-15

    An investigation was conducted to study the suitability of vegetable oils as bioquenchants for industrial heat treatment. The study involved the assessment of the severity of quenching and wetting behaviour of conventional and vegetable oil quench media. Quench severities of sunflower, coconut and palm oils were found to be greater than mineral oil. The quench severity of aqueous media is greater than oil media although their wettability is poor as indicated by their higher contact angles. A dimensionless contact angle parameter defined in this work is found to be a better parameter to compare the wetting behaviour with heat transfer. (author)

  20. 5,7-Dimethoxycoumarin prevents chronic mild stress induced depression in rats through increase in the expression of heat shock protein-70 and inhibition of monoamine oxidase-A levels

    Directory of Open Access Journals (Sweden)

    Wei Yang

    2018-02-01

    Full Text Available The current study was aimed to investigate the role of 5,7-dimethoxycoumarin in the prevention of chronic mild stress induced depression in rats. The chronic mild stress rat model was prepared using the known protocols. The results from open-field test showed that rats in the chronic mild stress group scored very low in terms of crossings and rearings than those of the normal rats. However, pre-treatment of the rats with 10 mg/kg doses of 5,7-dimethoxycoumarin prevented decline in the locomotor activity by chronic mild stress. The level of monoamine oxidase-A in the chronic mild stress rat hippocampus was markedly higher. Chronic mild stress induced increase in the monoamine oxidase-A level was inhibited by pre-treatment with 10 mg/kg doses of 5,7-dimethoxycoumarin in the rats. Chronic mild stress caused a marked increase in the level of caspase-3 mRNA and proteins in rat hippocampus tissues. The increased level of caspase-3 mRNA and protein level was inhibited by treatment of rats with 5,7-dimethoxycoumarin (10 mg/kg. 5,7-Dimethoxycoumarin administration into the rats caused a marked increase in the levels of heat shock protein-70 mRNA and protein. The levels of heat shock protein-70 were markedly lower both in normal and chronic mild stress groups of rats compared to the 5,7-dimethoxycoumarin treated groups. Thus 5,7-dimethoxycoumarin prevented the chronic mild stress induced depression in rats through an increase in the expression of heat shock protein-70 and inhibition of monoamine oxidase-A levels.

  1. 5,7-Dimethoxycoumarin prevents chronic mild stress induced depression in rats through increase in the expression of heat shock protein-70 and inhibition of monoamine oxidase-A levels.

    Science.gov (United States)

    Yang, Wei; Wang, Huanlin

    2018-02-01

    The current study was aimed to investigate the role of 5,7-dimethoxycoumarin in the prevention of chronic mild stress induced depression in rats. The chronic mild stress rat model was prepared using the known protocols. The results from open-field test showed that rats in the chronic mild stress group scored very low in terms of crossings and rearings than those of the normal rats. However, pre-treatment of the rats with 10 mg/kg doses of 5,7-dimethoxycoumarin prevented decline in the locomotor activity by chronic mild stress. The level of monoamine oxidase-A in the chronic mild stress rat hippocampus was markedly higher. Chronic mild stress induced increase in the monoamine oxidase-A level was inhibited by pre-treatment with 10 mg/kg doses of 5,7-dimethoxycoumarin in the rats. Chronic mild stress caused a marked increase in the level of caspase-3 mRNA and proteins in rat hippocampus tissues. The increased level of caspase-3 mRNA and protein level was inhibited by treatment of rats with 5,7-dimethoxycoumarin (10 mg/kg). 5,7-Dimethoxycoumarin administration into the rats caused a marked increase in the levels of heat shock protein-70 mRNA and protein. The levels of heat shock protein-70 were markedly lower both in normal and chronic mild stress groups of rats compared to the 5,7-dimethoxycoumarin treated groups. Thus 5,7-dimethoxycoumarin prevented the chronic mild stress induced depression in rats through an increase in the expression of heat shock protein-70 and inhibition of monoamine oxidase-A levels.

  2. Effect of heat treatment on the characteristics of tool steel deposited by the directed energy deposition process

    Science.gov (United States)

    Park, Jun Seok; Lee, Min-Gyu; Cho, Yong-Jae; Sung, Ji Hyun; Jeong, Myeong-Sik; Lee, Sang-Kon; Choi, Yong-Jin; Kim, Da Hye

    2016-01-01

    The directed energy deposition process has been mainly applied to re-work and the restoration of damaged steel. Differences in material properties between the base and the newly deposited materials are unavoidable, which may affect the mechanical properties and durability of the part. We investigated the effect of heat treatment on the characteristics of tool steel deposited by the DED process. We prepared general tool steel materials of H13 and D2 that were deposited onto heat-treated substrates of H13 and D2, respectively, using a direct metal tooling process. The hardness and microstructure of the deposited steel before and after heat treatment were investigated. The hardness of the deposited H13 steel was higher than that of wrought H13 steel substrate, while that of the deposited D2 was lower than that of wrought D2. The evolution of the microstructures by deposition and heat treatment varied depending on the materials. In particular, the microstructure of the deposited D2 steel after heat treatment consisted of fine carbides in tempered martensite and it is expected that the deposited D2 steel will have isotropic properties and high hardness after heat treatment.

  3. Aging of iron (hydr)oxides by heat treatment and effects on heavy metal binding

    DEFF Research Database (Denmark)

    Sørensen, Mette Abildgaard; Starckpoole, M. M.; Frenkel, A. I.

    2000-01-01

    their transformations caused by heat treatment prior to disposal or aging at a proper disposal site. The transformations were investigated by XRD, SEM, XANES, EXAFS, surface area measurements, pH static leaching tests, and extractions with oxalate and weak hydrochloric acid. It was found that at 600 and 900 °C the iron...... oxides were transformed to hematite, which had a greater thermodynamic stability but less surface area than the initial products. Heat treatment also caused some volatilization of heavy metals (most notably, Hg). Leaching with water at pH 9 (L/S 10, 24 h) and weak acid extraction showed that heat...

  4. Modification of the original color of the Eucalyptus grandis wood by heat treatments

    Directory of Open Access Journals (Sweden)

    Rosilei Aparecida Garcia

    2014-09-01

    Full Text Available The objective of this study was to determine the modification of original color of Eucalyptus grandis Hill ex. Maiden wood after heat-treatment. Wood samples were heat-treated under different temperatures (180, 200, 215 and 230ºC and time conditions (15 minutes, 2 and 4 hours. Color analysis were performed on the CIE L*a*b* system by using a Color Eye XTH-X-Rite 200d spectrophotometer. All heat treatments promoted an alteration of the original color of wood. Heat-treated woods presented lower L* (lightness values than untreated wood (control, characterizing the wood darkness, mainly for more severe conditions of temperature and time. Chromatic coordinates (a* and b* showed different behaviors depending on the temperature-time combination. The modification of the original color of the wood allowed the creation of new color patterns, which can add greater value to the studied wood.

  5. Differential Response to Heat Stress in Outer and Inner Onion Bulb Scales.

    Science.gov (United States)

    Galsurker, Ortal; Doron-Faigenboim, Adi; Teper-Bamnolker, Paula; Daus, Avinoam; Lers, Amnon; Eshel, Dani

    2018-05-18

    Brown protective skin formation in onion bulbs can be induced by rapid postharvest heat treatment. Onions that were peeled to different depths and were exposed to heat stress showed that only the outer scale formed dry brown skin, whereas the inner scales maintained high water content and did not change color. Our results reveal that browning of the outer scale during heat treatment is due to an enzymatic process that is associated with high levels of oxidation components, such as peroxidase and quercetin glucoside. De-novo transcriptome analysis revealed differential molecular responses of the outer and inner scales to the heat stress. Genes involved in lipid metabolism, oxidation pathways and cell-wall modification were highly expressed in the outer scale during heating. Defense-response-related genes such as those encoding heat-shock proteins, antioxidative stress defense or production of osmoprotectant metabolites were mostly induced in the inner scale in response to the heat exposure. These transcriptomic data led to a conceptual model that suggests sequential processes for browning development and desiccation of the outer scales versus processes associated with defense response and heat tolerance in the inner scale. Thus, the observed physiological differences between the outer and inner scales is supported by the identified molecular differences.

  6. Improving the conductivity of single-walled carbon nanotubes films by heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jiaping [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Superfine Microstructures, 1295 Dingxi Road, Shanghai 200050 (China); Sun Jing, E-mail: jingsun@mail.sic.ac.c [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Superfine Microstructures, 1295 Dingxi Road, Shanghai 200050 (China); Gao Lian, E-mail: liangaoc@online.sh.c [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Superfine Microstructures, 1295 Dingxi Road, Shanghai 200050 (China); Liu Yangqiao; Wang Yan; Zhang Jing [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Superfine Microstructures, 1295 Dingxi Road, Shanghai 200050 (China); Kajiura, Hisashi; Li Yongming; Noda, Kazuhiro [Advanced Materials Laboratories, Sony Corporation, Atsugi Tec. No. 2, 4-16-1 Okata Atsugi, Kanagawa 243-0021 (Japan)

    2009-10-19

    A simple heat treatment method was applied to remove surfactants remaining in the single-walled carbon nanotubes (SWNTs) films at 300 deg. C for 5 h in air. Scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and reflected light interference microscope (RLIM) were employed to verify the elimination of surfactants. The comprehensive performance, especially the conductivity, could be improved by more than one order after heat treatment. For example, using SDBS as dispersant, the sheet resistance decreased from 782,600 OMEGA/square to 40,460 OMEGA/square with the transmittance of about 99.5% at 550 nm.

  7. The kinetics of removal of heat-induced excess nuclear protein

    International Nuclear Information System (INIS)

    Roti, J.L.R.; Uygur, N.; Higashikubo, R.

    1984-01-01

    To investigate the role of protein content, temperature and heating time in the removal of heat-induced excess protein associated with the isolated nucleus, the kinetics of protein removal was monitored for 6 to 8 hours following exposure to 7 hyperthermic protocols. Four of these (47 0 C-7.5 min., 46 0 C-15 min., 45 0 C-30 min., and 44 0 C-60 min.) resulted in a nuclear protein content approximately twice that of nuclei from unheated cells (2.05 +- .14) following heat exposure. Three protocols (45 0 C-15 min., 44 0 C-30 min. and 43 0 C-60 min.) resulted in a nuclear protein content approximately 1.6 times normal (1.63 +- .12). If nuclear protein content were the only determinant in the recovery rate, then the same half time for nuclear protein removal would be expected within each group of protocols. Rate constants for nuclear protein removal were obtained by regression analysis. The half-time for nuclear protein removal increased with decreasing temperature and increasing heating time for the same nuclear protein content. This result suggests that the heating time and temperature are more of a determinant in the removal kinetics than protein content alone. Extended kinetics of recovery (to 36 hours) showed incomplete recovery and a secondary increase in protein associated with the isolated nucleus. These results were due to cell-cycle rearrangement (G/sub 2/ block) and unbalanced growth

  8. Study on mechanical properties of the laminated composite materials with compatible heat treatments

    International Nuclear Information System (INIS)

    Pashkov, P.O.; Pektemirov, B.G.; Yaroshenko, A.P.

    1980-01-01

    Considered is the behaviour during axial extension of trilament composite materials, the mechanical properties of which are formed mainly by heat treatment. Application in the composite of the materials with compatible heat treatment is most rational. It is shown that for (ATsMg+N18K8M5T+ATsMg), (KhN78+VKS+KhH78) composites, the constituents of which are relatively plastic and tightly bound with each other, the tensile strength and uniform strain are changed additively

  9. Islet-cell dysfunction induced by glucocorticoid treatment

    DEFF Research Database (Denmark)

    van Raalte, Daniël H; Kwa, Kelly A A; van Genugten, Renate E

    2013-01-01

    Glucocorticoids impair glucose tolerance by inducing insulin resistance. We investigated the dose-dependent effects of glucocorticoid treatment on islet-cell function in healthy males and studied the role of the autonomic nervous system.......Glucocorticoids impair glucose tolerance by inducing insulin resistance. We investigated the dose-dependent effects of glucocorticoid treatment on islet-cell function in healthy males and studied the role of the autonomic nervous system....

  10. Thermoluminescence and cathodoluminescence studies of calcite and MgO: surface defects and heat treatment

    International Nuclear Information System (INIS)

    Goeksu, H.Y.; Brown, L.M.

    1988-01-01

    Some of the problems which preclude accurate thermoluminescence (TL) dating of geologically formed calcite stem from different sample pre-treatment procedures, such as grinding, drilling or pre-heating. It has long been known that grinding can introduce spurious TL in calcite, but there have been wide differences of opinion as to the magnitude of the influence and its importance. Therefore, various grinding and acid-washing procedures have been suggested to avoid spurious thermoluminescence. Various models have been developed to explain the mechanism. We have studied the changes in thermoluminescence (TL) and cathodoluminescence (CL) properties as well as in the spectral composition of the glow from calcite and MgO due to surface defects and heat treatment. It is found that both laboratory heat treatment and surface indents give rise to changes in TL efficiency. (author)

  11. Effect of heat treatment time on microstructure and electrical conductivity in LATP glass ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Sonigra, Dhiren, E-mail: somans@iitb.ac.in, E-mail: ajit.kulkarni@iitb.ac.in; Soman, Swati, E-mail: somans@iitb.ac.in, E-mail: ajit.kulkarni@iitb.ac.in; Kulkarni, Ajit R., E-mail: somans@iitb.ac.in, E-mail: ajit.kulkarni@iitb.ac.in [Dept. of Metallurgical Engineering and Materials Science, IIT Bombay, Mumbai-400076 (India)

    2014-04-24

    Glass-ceramic is prepared by heat treatment of melt quenched 14Li{sub 2}O−9Al{sub 2}O{sub 3}−38TiO{sub 2}−39P{sub 2}O{sub 5} glass in the vicinity of crystallization temperature. Growth of ceramic phase is controlled by tuning heat treatment time at fixed temperature. Ceramic phase was identified to be LiTi{sub 2}(PO{sub 4}){sub 3} from X Ray Diffraction analysis. Microstructural evolution of this phase with hold time was observed under high resolution Scanning Electron Microscope. DC conductivity is observed to increase by 4-5 orders of magnitude in this glass-ceramic compared to parent glass. However, formation of pores and cracks with very large heat treatment time seem to hinder further increase of conductivity.

  12. Effects of heat-shock treatment and genotype on radiosensitivity of maize seeds

    International Nuclear Information System (INIS)

    Yamagata, Hirotada; Tanisaka, Takatoshi; Harima, Kunio

    1975-01-01

    In order to clarify the internal and external factors responsible for radiosensitivity of seed, and to induce mutations more effectively, two experiments were conducted using maize. (1) Seeds of an inbred line were irradiated with γ rays at an extremely low temperature (-70 0 C) and then dipped in hot water (60 0 C, 30 sec.). Through such heat-shock treatment the radiosensitivity of maize seeds was remarkably reduced: LD 50 and RD 50 for growth rose as high as about three times and about twice, respectively. (2) Seeds of seven strains including four inbred lines, two single-cross hybrids and one double-cross hybrid were exposed to γ rays by the ordinary procedure. Hybrids, regardless of whether they were single cross or double cross, were clearly proved to surpass their parental strains in radiation tolerance, both in survival rate and in culm length. These descents of radiosensitivity were considered to be due mainly to the increased heterozygosity. (auth.)

  13. The effects of heat treatment on physical and technological ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... surface of wood were used to evaluate the effect of heat treatment on the surface characteristics of ... Some of the products developed by thermal treat- .... boards were stored uncontrolled condition in an unheated room for .... These results can be explained with material loses in ...... Finland-state of the art.

  14. Rapid insight into heating-induced phase transformations in the solid state of the calcium salt of atorvastatin using multivariate data analysis

    DEFF Research Database (Denmark)

    Christensen, Niels Peter Aae; Van Eerdenbrugh, Bernard; Kwok, Kaho

    2013-01-01

    To investigate the heating-induced dehydration and melting behavior of the trihydrate phase of the calcium salt of atorvastatin.......To investigate the heating-induced dehydration and melting behavior of the trihydrate phase of the calcium salt of atorvastatin....

  15. Optimisasi Suhu Pemanasan dan Kadar Air pada Produksi Pati Talas Kimpul Termodifikasi dengan Teknik Heat Moisture Treatment (HMT (Optimization of Heating Temperature and Moisture Content on the Production of Modified Cocoyam Starch Using Heat Moisture Treatment (HMT Technique

    Directory of Open Access Journals (Sweden)

    I Nengah Kencana Putra

    2016-12-01

    Full Text Available One of the physically starch modification technique is heat-moisture treatment (HMT. This technique can increase the resistance of starch to heat, mechanical treatment, and acid during processing.  This research aimed to find out the influence of heating temperature and moisture content in the modification process of cocoyam starch  with HMT techniques on the characteristic of product, and then to determine the optimum heating temperature and moisture content in the process. The research was designed with a complete randomized design (CRD with two factors factorial experiment.  The first factor was temperature of the heating consists of 3 levels namely 100 °C, 110 °C, and 120 °C. The second factor was the moisture content of starch which consists of 4 levels, namely 15 %, 20 %, 25 %, and 30 %. The results showed that the heating temperature and moisture content significantly affected water content, amylose content and swelling power of modified cocoyam starch product, but the treatment had no significant effect on the solubility of the product. HMT process was able to change the type of cocoyam starch from type B to type C. The optimum heating temperature and water content on modified cocoyam starch production process was 110 °C and 30 % respectively. Such treatment resulted in a modified cocoyam starch with moisture content of 6.50 %, 50,14 % amylose content, swelling power of 7.90, 0.0009% solubility, paste clarity of 96.310 % T, and was classified as a type C starch.   ABSTRAK Salah satu teknik modifikasi pati secara fisik adalah teknik Heat Moisture Treatment (HMT. Teknik ini dapat meningkatkan ketahanan pati terhadap panas, perlakuan mekanik, dan asam selama pengolahan. Penelitian ini bertujuan untuk mengetahui pengaruh suhu dan kadar air pada proses modifikasi pati talas kimpul dengan teknik HMT terhadap karakteristik produk, dan selanjutnya menentukan suhu dan kadar air yang optimal dalam proses tersebut. Penelitian ini dirancang

  16. Effect of heat treatment on CO2 adsorption of KOH-activated graphite nanofibers.

    Science.gov (United States)

    Meng, Long-Yue; Park, Soo-Jin

    2010-12-15

    In this work, graphite nanofibers (GNFs) were successfully expanded intercalating KOH followed by heat treatment in the temperature range of 700-1000 °C. The aim was to improve the CO(2) adsorption capacity of the GNFs by increasing the porosity of GNFs. The effects of heat treatment on the pore structures of GNFs were investigated by N(2) full isotherms, XRD, SEM, and TEM. The CO(2) adsorption capacity was measured by CO(2) isothermal adsorption at 25 °C and 1 atm. From the results, it was found that the activation temperature had a major influence on CO(2) adsorption capacity and textural properties of GNFs. The specific surface area, total pore volume, and mesopore volume of the GNFs increased after heat treatment. The CO(2) adsorption isotherms showed that G-900 exhibited the best CO(2) adsorption capacity with 59.2 mg/g. Copyright © 2010 Elsevier Inc. All rights reserved.

  17. Effects of rare sugar d-allulose on heat-induced gelation of surimi prepared from marine fish.

    Science.gov (United States)

    Ogawa, Masahiro; Inoue, Masaki; Hayakawa, Shigeru; O'Charoen, Siwaporn; Ogawa, Makiko

    2017-11-01

    d-Allulose (Alu), the C3-epimer of d-fructose, is a non-caloric sweetener (0.39 kcal g -1 ) with a suppressive effect on postprandial blood glucose elevation. The aim of this study was to investigate the effects of Alu used as a sweetener and gel improver instead of sucrose on heat-induced gelation of surimi. The puncture test of a heat-induced surimi gel showed that with 50 g kg -1 Alu the gel had 15% and 6% higher gel strength than the corresponding gel with sucrose (Suc) and with sorbitol (Sor), respectively. In addition, Alu-gel had 26% and 25% higher water-holding capacity (WHC) than Suc- and Sor-gel. Heating of myofibrillar protein with Alu, unlike Suc and Sor, facilitated the formation of both disulfide and non-disulfide crosslinks that might be associated with the mechanical properties and WHC of Alu-gel. Alu improves the mechanical properties and WHC of the heat-induced surimi gel. Furthermore, Alu is low in calories compared with Suc (4.0 kcal g -1 ) and Sor (3.0 kcal g -1 ). Thus Alu will be an alternative of Suc or Sor for developing surimi-based products with health benefits. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Microsegregation of heat and homogenization treatments in uranium-niobium alloys (U-Nb)

    International Nuclear Information System (INIS)

    Leal, J.F.

    1988-01-01

    In the following sections microsegration results in U-3,6 Wt% Nb and U-6,1 Wt% Nb alloys casted in noconsumable electrode arc furnace are presented. The microsegration is studied qualitatively by optical microscopy and quantitatively by electron microprobe. The degree of homogenization has been measured after 800 and 850 0 C heat treatments in tubular resistive furnace. The microstructures after heat treatments are quantitatively analysed to check effects on the casting structures, mainly the variations in solute along the dendrite arm spacing. Some solidification phenomena are then discussed on reference to theorical models of dendritic solidification, including microstructure and microsegregation. The experimental results are compared to theoretical on basis of initial and residual microsegregation after homogenization treatments. The times required for homogenization of the alloys are also discussed in function of the microsegregation from casting structures and the temperatures of the treatments. (author) [pt

  19. Effects of Two-stage Heat Treatment on Delayed Coke and Study of Their Surface Texture Characteristics

    Science.gov (United States)

    Im, Ui-Su; Kim, Jiyoung; Lee, Seon Ho; Lee, Byung-Rok; Peck, Dong-Hyun; Jung, Doo-Hwan

    2017-12-01

    In the present study, surface texture features and chemical properties of two types of cokes, made from coal tar by either 1-stage heat treatment or 2-stage heat treatment, were researched. The relationship between surface texture characteristics and the chemical properties was identified through molecular weight distribution, insolubility of coal tar, weight loss with temperature increase, coking yield, and polarized light microscope analysis. Rapidly cleared anisotropy texture in cokes was observed in accordance with the coking temperature rise. Quinoline insolubility and toluene insolubility of coal tar increased with a corresponding increases in coking temperature. In particular, the cokes produced by the 2-stage heat treatment (2S-C) showed surface structure of needle cokes at a temperature approximately 50°C lower than the 1-stage heat treatment (1S-C). Additionally, the coking yield of 2S-C increased by approximately 14% in comparison with 1S-C.

  20. Effect of heat treatment to sweet potato flour on dough properties and characteristics of sweet potato-wheat bread.

    Science.gov (United States)

    Pérez, Isela Carballo; Mu, Tai-Hua; Zhang, Miao; Ji, Lei-Lei

    2017-12-01

    The effect of heat treatment at 90, 100, 110 and 120 ℃ for 20 min to sweet potato flour on dough properties and characteristics of sweet potato-wheat bread was investigated. The lightness (L*) and a* of sweet potato flour samples after heat treatment were increased, while the b* were decreased significantly, as well as the particle size, volume and area mean diameter ( p sweet potato flour was observed, where the number of irregular granules increased as the temperature increased from 90 to 120 ℃. Compared with sweet potato flour samples without heat treatment and with heat treatment at 90, 100 and 120 ℃, the gelatinization temperature and enthalpy change of sweet potato flour at 110 ℃ were the lowest, which were 77.94 ℃ and 3.67 J/g, respectively ( p sweet potato flour increased significantly from 1199 ml without heat treatment to 1214 ml at 90 ℃ ( p sweet potato-wheat bread with sweet potato flour after heat treatment increased significantly, which was the largest at 90 ℃ (2.53 cm 3 /g) ( p sweet potato flour could be potentially used in wheat bread production.

  1. Regenerative heat treatments for the extension of the creep life of the superalloy IN-738

    International Nuclear Information System (INIS)

    Stevens, R.A.; Flewitt, P.E.J.

    1979-01-01

    Uniaxial creep tests have been performed on the cast nickel-base superalloy IN-738 at 1023K and 1123K. Microstructural damage occurring during creep has been characterised using transmission electron microscopy of surface and extraction replicas. Considerable coarsening of the γ' precipitates occurs during creep causing a progressive loss of creep strength. Intermediate heat treatment of interrupted specimens regenerates a microstructure similar to the original, and on re-testing significant creep life extensions are observed. These heat treatments do not completely recover the creep life due to the development of grain boundary cavitation. Additional heat treatments were performed under a superimposed hydrostatic pressure of 138 MPa to remove these cavities. (orig.) [de

  2. Long-term heat stress induces the inflammatory response in dairy cows revealed by plasma proteome analysis.

    Science.gov (United States)

    Min, Li; Zheng, Nan; Zhao, Shengguo; Cheng, Jianbo; Yang, Yongxin; Zhang, Yangdong; Yang, Hongjian; Wang, Jiaqi

    2016-03-04

    In this work we employed a comparative proteomic approach to evaluate seasonal heat stress and investigate proteomic alterations in plasma of dairy cows. Twelve lactating Holstein dairy cows were used and the treatments were: heat stress (n = 6) in hot summer (at the beginning of the moderate heat stress) and no heat stress (n = 6) in spring natural ambient environment, respectively. Subsequently, heat stress treatment lasted 23 days (at the end of the moderate heat stress) to investigate the alterations of plasma proteins, which might be employed as long-term moderate heat stress response in dairy cows. Changes in plasma proteins were analyzed by two-dimensional electrophoresis (2-DE) combined with mass spectrometry. Analysis of the properties of the identified proteins revealed that the alterations of plasma proteins were related to inflammation in long-term moderate heat stress. Furthermore, the increase in plasma tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) directly demonstrated that long-term moderate heat stress caused an inflammatory response in dairy cows. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Improved corrosion resistance of aluminum brazing sheet by a post-brazing heat treatment

    NARCIS (Netherlands)

    Norouzi Afshar, F.; Tichelaar, F.D.; Glenn, A. M.; Taheri, P.; Sababi, M.; Terryn, H.A.; Mol, J.M.C.

    2017-01-01

    This work studies the influence of the microstructure on the corrosion mechanism and susceptibility of as-brazed aluminum sheet. Various microstructures are obtained using postbrazing heat treatments developed to enhance the corrosion resistance of an AA4xxx/AA3xxx brazing sheet. The heat

  4. Effects of Induction Heat Bending and Heat Treatment on the Boric Acid Corrosion of Low Alloy Steel Pipe for Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki-Tae; Kim, Young-Sik [Andong National University, Gyeongbuk (Korea, Republic of); Chang, Hyun-Young; Park, Heung-Bae [KEPCO EandC, Gyeongbuk (Korea, Republic of); Sung, Gi-Ho; Shin, Min-Chul [Sungil SIM Co. Ltd, Busan (Korea, Republic of)

    2016-11-15

    In many plants, including nuclear power plants, pipelines are composed of numerous fittings such as elbows. When plants use these fittings, welding points need to be increased, and the number of inspections also then increases. As an alternative to welding, the pipe bending process forms bent pipe by applying strain at low or high temperatures. This work investigates how heat treatment affects on the boric acid corrosion of ASME SA335 Gr. P22 caused by the induction heat bending process. Microstructure analysis and immersion corrosion tests were performed. It was shown that every area of the induction heat bent pipe exhibited a high corrosion rate in the boric acid corrosion test. This behavior was due to the enrichment of phosphorous in the ferrite phase, which occurred during the induction heat bending process. This caused the ferrite phase to act as a corrosion initiation site. However, when re-heat treatment was applied after the bending process, it enhanced corrosion resistance. It was proved that this resistance was closely related to the degree of the phosphorus segregation in the ferrite phase.

  5. Effect of heat treatment of whole cottonseed on in vitro, in situ and in ...

    African Journals Online (AJOL)

    Keywords: Amino acid flow, heat treatment, protein degradation, whole cononseed. * Author to whom ... heat-treated soybearu were compared with raw soybeans, it was found that ... et al., 1985; Faldet & Sarter, 1989) while milk fat percenrage.

  6. Influence of lactic acid and post-treatment recovery time on the heat resistance of Listeria monocytogenes.

    Science.gov (United States)

    Omori, Yasuo; Miake, Kiyotaka; Nakamura, Hiromi; Kage-Nakadai, Eriko; Nishikawa, Yoshikazu

    2017-09-18

    The aim of this study was to evaluate the effect of lactic acid (LA) with and without organic material at various post-treatment recovery times on the heat resistance of Listeria monocytogenes (Lm). LA decreased Lm numbers; however, the effect was remarkably attenuated by the presence of organic matter. Five strains of Lm were treated with LA and the listericidal effects were compared. The effect of LA varied depending on the strain, with ≥3.0% (w/w) LA required to kill the Lm strains in a short time. The heat resistance of Lm treated with LA was examined with respect to the time interval between the acid treatment and the subsequent manufacturing step. The heat resistance of Lm was shown to significantly increase during the post-treatment period. Heat tolerance (D value) increased up to 3.4-fold compared with the non-treated control bacteria. RNA sequencing and RT-PCR analyses suggested that several stress chaperones, proteins controlled by RecA and associated with high-temperature survival, were involved in the mechanism of enhanced heat resistance. These results are applicable to manufacturers when LA and heat treatment methods are utilized for the effective control of Lm in foods. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Significance of heat-moisture treatment conditions on the pasting and gelling behaviour of various starch-rich cereal and pseudocereal flours.

    Science.gov (United States)

    Collar, Concha

    2017-10-01

    The impact of heat-moisture treatment processing conditions (15%, 25%, and 35% moisture content; 1, 3, and 5 h heating time at 120 ℃) on the viscosity pasting and gelling profiles of different grain flours matrices (barley, buckwheat, sorghum, high β-glucan barley, and wheat) was investigated by applying successive cooking and cooling cycles to rapid visco analyser canisters with highly hydrated samples (3.5:25, w:w). At a milder heat-moisture treatment conditions (15% moisture content, 1 h heating time), except for sorghum, heat-moisture treatment flours reached much higher viscosity values during earlier pasting and subsequent gelling than the corresponding native counterparts. Besides heat-moisture treatment wheat flour, the described behaviour found also for non-wheat-treated flours has not been previously reported in the literature. An increased hydrophobicity of prolamins and glutelins in low moisture-short heating time heat-moisture treatment of non-wheat flours with high protein content (12.92%-19.95%) could explain the enhanced viscosity profile observed.

  8. Heat- and radiation-induced radio- and thermo-tolerance of Zea mays seedlings

    International Nuclear Information System (INIS)

    Gikoshvili, T.I.; Vagabova, M.Eh.; Vilenchik, M.M.; Kuzin, A.M.

    1985-01-01

    It was shown that γ-irradiation of Zea mays seedlings with low doses (1-3 Gy) induced thermotolerance, and preheating up to 43 deg C increased their radioresistance and thermotolerance. A hypothesis of the formation of common protective proteins after exposure to low - level radiation and heat is discussed

  9. Effect of heat treatment on polyphenol oxidase and peroxidase ...

    African Journals Online (AJOL)

    Effect of heat treatment (55°C/20 min) on polyphenol oxidase (PPO) and peroxidase (POD) activities and total phenolic compounds was investigated in Algerian dates (Deglet Nour variety) at Tamar (fully ripe) stage and in dates stored for 5 months at ambient temperature and in cold storage (10°C). Results obtained ...

  10. Predicting outgrowth and inactivation of Clostridium perfringens in meat products during low temperature long time heat treatment

    DEFF Research Database (Denmark)

    Duan, Zhi; Holst Hansen, Terese; Hansen, Tina Beck

    OBJECTIVE Sous-vide cooking and molecular gastronomy has started a wave of experimenting with Low Temperature Long Time (LTLT) heat treatments. Heat treatments, at temperatures as low as 50°C, have been suggested by celebrity chefs. LTLT treatments often take hours to reach to the final core...

  11. Effects of the Solid Solution Heat Treatment on the Corrosion Resistance Property of SSC13 Cast Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kuk-Jin [Hi-Sten Co., Ltd., Gimhae (Korea, Republic of); Lim, Su Gun [Gyeongsang National University, Jinju (Korea, Republic of); Pak, S. J. [Gachon BioNano Research Institute, Gachon University, Sungnam (Korea, Republic of)

    2015-04-15

    Recently, Stainless steels have been increasingly selected as the fitting or the valve materials of water pipes as the human health issue is getting higher and higher. Therefore, the connectors attached at pipes to deliver water are exposed to more severe environments than the pipes because crevice or galvanic corrosion is apt to occur at the fittings or the valves. Effects of the solid solution annealing, cooling rate after this heat treatment, and passivation on the corrosion properties of the shell mold casted SSC13 (STS304 alloy equivalent) were studied. The heating and quenching treatment more or less reduced hardness but effectively improved corrosion resistance. It was explained by the reduction of delta ferrite contents. Independent of heat treatment, the chemical passivation treatment also lowered corrosion rate but the improvement of corrosion resistance depended on temperature and time for passivation treatment indicating that the optimum conditions for passivation treatment were the bath temperature of 34 .deg. C and operating time of 10 minutes. Therefore it is suggested that the corrosion resistance of SSC13 can be effectively improved with the heat treatment, where SSC13 is heated for 10 minutes at 1120 °C and quenched and passivation treatment, where SSC13 is passivated for at least 10 seconds at 34 °C nitric acid solution.

  12. Influence of Heat Treatment on the Morphologies of Copper Nanoparticles Based Films by a Spin Coating Method

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2017-01-01

    Full Text Available We have investigated the influence of heat treatment on the morphologies of copper nanoparticles based films on glass slides by a spin coating method. The experiments show that heat treatment can modify the sizes and morphologies of copper nanoparticles based films on glass slides. We suggest that through changing the parameters of heat treatment process may be helpful to vary the scattering and absorbing intensity of copper nanoparticles when used in energy harvesting/conversion and optical devices.

  13. Promotion of Pt-Ru/C catalysts driven by heat treated induced surface segregation for methanol oxidation reaction

    International Nuclear Information System (INIS)

    Wei Yuchen; Liu Chenwei; Chang Weijung; Wang Kuanwen

    2011-01-01

    Research highlights: → Thermal treatments on the Pt-Ru/C induce different extents of surface segregation. → O 2 treatment results in obvious Ru segregation and formation of RuO 2 . → Catalysts treated in H 2 have the excellent CO de-poisoning ability. → N 2 treatment suppresses the surface Pt depletion and hence promotes the MOR. - Abstract: Carbon supported Pt-Ru/C (1:1) alloy catalysts supplied by E-TEK are widely used for fuel cell research. Heat treatments in various atmospheres are conducted for the promotion of the methanol oxidation reaction (MOR) and the investigation of the structure-activity relationship (SAR) of the catalysts. The alloy structures, surface compositions, surface species, and electro-catalytic activities of the alloy catalysts are characterized by X-ray diffraction (XRD), temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV), respectively. The as-received Pt-Ru/C catalysts have a Ru rich in the inner core and Pt rich on the outer shell structure. Thermal treatments on the catalysts induce Ru surface segregation in different extents and thereby lead to their alteration of the alloying degrees. O 2 treatment results in obvious Ru segregation and formation of RuO 2 . Catalysts treated in H 2 have the highest I f /I b value in the CV scans among all samples, indicating the catalysts have the excellent CO de-poisoning ability as evidenced by anodic CO stripping experiments. N 2 treatment may serve as an adjustment process for the surface composition and structure of the catalysts, which can suppress the surface Pt depletion (∼60% Pt on the surface), make the components stable and hence promote the MOR significantly.

  14. Promotion of Pt-Ru/C catalysts driven by heat treated induced surface segregation for methanol oxidation reaction

    Energy Technology Data Exchange (ETDEWEB)

    Wei Yuchen; Liu Chenwei; Chang Weijung [Institute of Materials Science and Engineering, National Central University, Taoyuan 32001, Taiwan (China); Wang Kuanwen, E-mail: kuanwen.wang@gmail.com [Institute of Materials Science and Engineering, National Central University, Taoyuan 32001, Taiwan (China)

    2011-01-12

    Research highlights: > Thermal treatments on the Pt-Ru/C induce different extents of surface segregation. > O{sub 2} treatment results in obvious Ru segregation and formation of RuO{sub 2}. > Catalysts treated in H{sub 2} have the excellent CO de-poisoning ability. > N{sub 2} treatment suppresses the surface Pt depletion and hence promotes the MOR. - Abstract: Carbon supported Pt-Ru/C (1:1) alloy catalysts supplied by E-TEK are widely used for fuel cell research. Heat treatments in various atmospheres are conducted for the promotion of the methanol oxidation reaction (MOR) and the investigation of the structure-activity relationship (SAR) of the catalysts. The alloy structures, surface compositions, surface species, and electro-catalytic activities of the alloy catalysts are characterized by X-ray diffraction (XRD), temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV), respectively. The as-received Pt-Ru/C catalysts have a Ru rich in the inner core and Pt rich on the outer shell structure. Thermal treatments on the catalysts induce Ru surface segregation in different extents and thereby lead to their alteration of the alloying degrees. O{sub 2} treatment results in obvious Ru segregation and formation of RuO{sub 2}. Catalysts treated in H{sub 2} have the highest I{sub f}/I{sub b} value in the CV scans among all samples, indicating the catalysts have the excellent CO de-poisoning ability as evidenced by anodic CO stripping experiments. N{sub 2} treatment may serve as an adjustment process for the surface composition and structure of the catalysts, which can suppress the surface Pt depletion ({approx}60% Pt on the surface), make the components stable and hence promote the MOR significantly.

  15. Hyperthermia: an effective strategy to induce apoptosis in cancer cells.

    Science.gov (United States)

    Ahmed, Kanwal; Tabuchi, Yoshiaki; Kondo, Takashi

    2015-11-01

    Heat has been used as a medicinal and healing modality throughout human history. The combination of hyperthermia (HT) with radiation and anticancer agents has been used clinically and has shown positive results to a certain extent. However, the clinical results of HT treatment alone have been only partially satisfactory. Cell death following HT treatment is a function of both temperature and treatment duration. HT induces cancer cell death through apoptosis; the degree of apoptosis and the apoptotic pathway vary in different cancer cell types. HT-induced reactive oxygen species production are responsible for apoptosis in various cell types. However, the underlying mechanism of signal transduction and the genes related to this process still need to be elucidated. In this review, we summarize the molecular mechanism of apoptosis induced by HT, enhancement of heat-induced apoptosis, and the genetic network involved in HT-induced apoptosis.

  16. Heat treatment of processing sludge of ornamental rocks: application as pozzolan in cement matrices

    Directory of Open Access Journals (Sweden)

    J.G. Uliana

    Full Text Available The sector of ornamental rocks produces significant volume of waste during the sawing of the blocks and demand to find ways to recycle, given its environmental impact. Considering the possibilities of use of industrial by-products as mineral admixtures, aiming at sustainable development in the construction industry, this paper aims to study the performance of the processing sludge of ornamental rocks and grinding after heat treatment, based on their potential application as partial substitute for cement. The residue was characterized, cast and milled to produce glassy material. Was analyzed the mechanical performance and pozzolanic activity with partial replacement of cement by waste in natural condition and after heat treatment in mortars for comparison. The results were promising, so it was possible to verify that after heat treatment, the treated waste is presented as a material with pozzolanic characteristics.

  17. Examination of the influence of heat treatment on the properties of Al-Si alloys

    Energy Technology Data Exchange (ETDEWEB)

    Vuksanovic, D.; Rakocevic, S. [Faculty of Metallurgy, Podgorica (RS); Markovic, S. [Faculty of Technology and Metallurgy, Belgrade (RS); Petrovic, T. [Institute ' Kirilo Savic' , Belgrade (RS); Kovacevic, K. [Institute for Ferrous Metallurgy (RS); Tripkovic, S. [H.K. Petar Drapsin, Mladenovac (RS)

    2007-08-15

    In this paper the influence of heat treatment on the structural and mechanical properties of Al-Si alloys was investigated. Silicon content in the examined alloys was in the range 11 to 14%, the contents of the other alloying elements were in the standard range but all alloys were modified with strontium. The regime of the applied heat treatment was quenching (520 C/6h - cooling in water) + aging (205oC/7h - air cooling). The examinations were carried out at room temperature as well as at 250 C and 300 C. The obtained results showed a positive influence of the applied heat treatment on the mechanical properties of the examined alloys. The improvement of the mechanical properties can be considered as a consequence of a redistribution and change of morphology of the phases present in the structure of the alloys. (orig.)

  18. Influence of heat treatments upon the mechanical properties and in vitro bioactivity of ZrO2-toughened MgO-CaO-SiO2-P2O5-CaF2 glass-ceramics.

    Science.gov (United States)

    Li, Huan-Cai; Wang, Dian-Gang; Meng, Xiang-Guo; Chen, Chuan-Zhong

    2014-09-01

    Zirconia-toughened MgO-CaO-SiO2-P2O5-CaF2 glass-ceramics are prepared using sintering techniques, and a series of heat treatment procedures are designed to obtain a glass-ceramic with improved properties. The crystallization behavior, phase composition, and morphology of the glass-ceramics are characterized. The bending strength, elastic modulus, fracture toughness, and microhardness of the glass-ceramics are investigated, and the effect mechanism of heat treatments upon the mechanical properties is discussed. The bioactivity of glass-ceramics is then evaluated using the in vitro simulated body fluid (SBF) soaking test, and the mechanism whereby apatite forms on the glass-ceramic surfaces in the SBF solution is discussed. The results indicate that the main crystal phase of the G-24 sample undergoing two heat treatment procedures is Ca5(PO4)3F (fluorapatite), and those of the G-2444 sample undergoing four heat treatment procedures are Ca5(PO4)3F and β-CaSiO3 (β-wollastonite). The heat treatment procedures are found to greatly influence the mechanical properties of the glass-ceramic, and an apatite layer is induced on the glass-ceramic surface after soaking in the SBF solution.

  19. Effect of grain orientation and heat treatment on mechanical properties of pure W

    Energy Technology Data Exchange (ETDEWEB)

    Noto, Hiroyuki, E-mail: noto_hiroyuki@iae.kyoto-u.ac.jp [Graduate School of Energy Science, Kyoto University, Kyoto 611-0011 (Japan); Research Fellow of Japan Society for the Promotion of Science (Japan); Taniguchi, Shuichi [Graduate School of Energy Science, Kyoto University, Kyoto 611-0011 (Japan); Kurishita, Hiroaki; Matsuo, Satoru [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Ukita, Takashi; Tokunaga, Kazutoshi [Institute for Applied Mechanics, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Kimura, Akihiko [Institute of Advanced Energy, Kyoto University, Kyoto 611-0011 (Japan)

    2014-12-15

    The effect of grain orientation, heat-treatment temperature and test temperature on the mechanical properties of tungsten (W), which vary depending on plastic working and fabrication process, was investigated by mechanical testing of tensile or bending. Heavily worked W samples (1.5–2.0 mm in the final thickness) exhibit degradation of fracture strength due to recrystallization embrittlement after heat-treatment at 1240 °C (temperature of diffusion bonding between W and a candidate material of the Fe base support structure). On the other hand, W samples with lower thickness reduction rates do not suffer degradation of fracture strength after heating up to around 1300 °C, and show somewhat higher fracture strength by heat-treatment below 1300 °C than the samples in the as-received state. The observed behavior is a reflection of recovery of dislocations introduced by plastic working. High temperature tensile testing of ITER grade W with an anisotropic grain structure and S-TUN with an equiaxed grain structure revealed that both W grades exhibit plastic elongation at temperatures higher than 200 °C with essentially the same temperature dependence of yield strength, which is relatively insensitive to grain orientation in the structure at 200–1300 °C.

  20. Effect of grain orientation and heat treatment on mechanical properties of pure W

    International Nuclear Information System (INIS)

    Noto, Hiroyuki; Taniguchi, Shuichi; Kurishita, Hiroaki; Matsuo, Satoru; Ukita, Takashi; Tokunaga, Kazutoshi; Kimura, Akihiko

    2014-01-01

    The effect of grain orientation, heat-treatment temperature and test temperature on the mechanical properties of tungsten (W), which vary depending on plastic working and fabrication process, was investigated by mechanical testing of tensile or bending. Heavily worked W samples (1.5–2.0 mm in the final thickness) exhibit degradation of fracture strength due to recrystallization embrittlement after heat-treatment at 1240 °C (temperature of diffusion bonding between W and a candidate material of the Fe base support structure). On the other hand, W samples with lower thickness reduction rates do not suffer degradation of fracture strength after heating up to around 1300 °C, and show somewhat higher fracture strength by heat-treatment below 1300 °C than the samples in the as-received state. The observed behavior is a reflection of recovery of dislocations introduced by plastic working. High temperature tensile testing of ITER grade W with an anisotropic grain structure and S-TUN with an equiaxed grain structure revealed that both W grades exhibit plastic elongation at temperatures higher than 200 °C with essentially the same temperature dependence of yield strength, which is relatively insensitive to grain orientation in the structure at 200–1300 °C

  1. Microstructure and Mechanical Properties of Inconel 625 Alloy on Low Carbon Steel by Heat Treatment after Overlay Welding

    International Nuclear Information System (INIS)

    Kim, Seungpil; Jang, Jaeho; Kim, Jungsoo; Kim, Byung Jun; Sohn, Keun Yong; Nam, Dae-Geun

    2016-01-01

    Overlay welding technique is one of methods used to improve metal mechanical properties such as strength, toughness and corrosion resistance. Generally, Inconel 625 alloy is used for overlay welding layer on low carbon steels for economic consideration. However, the method produces some problems in the microstructure of the cast structure and some defects, caused by the elevated temperatures of the overlay process. To resolve these problems, heat treatments are required. In this study, Inconel 625 alloy was welded on a low carbon steel by the overlay welding process to investigate the resulting microstructure and mechanical properties. A double heat treatment was performed to improve the mechanical properties of the welding and substrate layers. It was found that Inconel 625 alloy had an austenite microstructure after the first heat treatment, but the low carbon steel had a ferrite-pearlite microstructure after the second heat treatment. After the double heat treatment, the sample showed the optimum hardness because of grain refinement and homogenization of the microstructure.

  2. Microstructure and Mechanical Properties of Inconel 625 Alloy on Low Carbon Steel by Heat Treatment after Overlay Welding

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seungpil; Jang, Jaeho; Kim, Jungsoo; Kim, Byung Jun; Sohn, Keun Yong; Nam, Dae-Geun [Korea Institute of Industrial Technology, Busan (Korea, Republic of)

    2016-08-15

    Overlay welding technique is one of methods used to improve metal mechanical properties such as strength, toughness and corrosion resistance. Generally, Inconel 625 alloy is used for overlay welding layer on low carbon steels for economic consideration. However, the method produces some problems in the microstructure of the cast structure and some defects, caused by the elevated temperatures of the overlay process. To resolve these problems, heat treatments are required. In this study, Inconel 625 alloy was welded on a low carbon steel by the overlay welding process to investigate the resulting microstructure and mechanical properties. A double heat treatment was performed to improve the mechanical properties of the welding and substrate layers. It was found that Inconel 625 alloy had an austenite microstructure after the first heat treatment, but the low carbon steel had a ferrite-pearlite microstructure after the second heat treatment. After the double heat treatment, the sample showed the optimum hardness because of grain refinement and homogenization of the microstructure.

  3. Effect of heat treatment on microstructure and mechanical properties of PIP-SiC/SiC composites

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Shuang, E-mail: zhsh6007@126.com [Key Laboratory of Advanced Ceramic Fibres and Composites, College of Aerospace and Materials Engineering, National University of Defense Technology, Changsha 410073 (China); School of Mechanical, Aerospace, and Civil Engineering, University of Manchester, Manchester M13 9PL (United Kingdom); Zhou, Xingui; Yu, Jinshan [Key Laboratory of Advanced Ceramic Fibres and Composites, College of Aerospace and Materials Engineering, National University of Defense Technology, Changsha 410073 (China); Mummery, Paul [School of Mechanical, Aerospace, and Civil Engineering, University of Manchester, Manchester M13 9PL (United Kingdom)

    2013-01-01

    Continuous SiC fibre reinforced SiC matrix composites (SiC/SiC) have been studied as materials for heat resistant and nuclear applications. Thermal stability is one of the key issues for SiC/SiC composites. In this study, 3D SiC/SiC composites are fabricated via the polymer impregnation and pyrolysis (PIP) process, and then heat treated at 1400 Degree-Sign C, 1600 Degree-Sign C and 1800 Degree-Sign C in an inert atmosphere for 1 h, respectively. The effect of heat treatment on microstructure and mechanical properties of the composites is investigated. The results indicate that the mechanical properties of the SiC/SiC composites are significantly improved after heat treatment at 1400 Degree-Sign C mainly because the mechanical properties of the matrix are greatly improved due to crystallisation. With the increasing of heat treatment temperature, the properties of the composites are conversely decreased because of severe damage of the fibres and the matrix.

  4. Enhancement of contractile force generation of artificial skeletal muscle tissues by mild and transient heat treatment.

    Science.gov (United States)

    Sato, Masanori; Ikeda, Kazushi; Kanno, Shota; Ito, Akira; Kawabe, Yoshinori; Kamihira, Masamichi

    2014-01-01

    Artificial skeletal muscle tissues composed of cells are expected to be used for applications of regenerative medicine and drug screening. Generally, however, the physical forces generated by tissue-engineered skeletal muscle are lower than those of skeletal muscle tissues found in the body. Local hyperthermia is used for many diseases including muscle injuries. It was recently reported that mild heat treatment improved skeletal muscle functions. In this study, we investigated the effects of mild heat treatment on the tissue-engineered skeletal muscle tissues in vitro. We used magnetite cationic liposomes to label C2C12 myoblast cells magnetically, and constructed densely packed artificial skeletal muscle tissues by using magnetic force. Cell culture at 39°C promoted the differentiation of myoblast cells into myotubes. Moreover, the mild and transient heat treatment improved the contractile properties of artificial skeletal muscle tissue constructs. These findings indicate that the culture method using heat treatment is a useful approach to enhance functions of artificial skeletal muscle tissue.

  5. Research on Crack-Filling Heat Treatment and Hydrogen Permeation Test of Self-healing Tritium Permeation Barriers

    Science.gov (United States)

    Liu, Dawei; Wang, Yan; Zhang, Ying; Ouyang, Taoyuan; Zhou, Tong; Fang, Xuanwei; Suo, Jinping

    2018-03-01

    A TiC + mixture (TiC/Al2O3 (1:1 wt.%)) +Al2O3 self-healing triple layer coating (TLC) was designed and manufactured by our group, and the crack-filling heat treatment process had been roughly explored in the past. In this work, the accelerating test with a thick TiC + mixture (TiC/Al2O3 (1:1 wt.%)) double-layer coating (DLC) was carried out. The DLC coating warped when the heat treatment temperature was lower than 550 °C, which was rare in similar researches, and it crushed into fan-shaped pieces when the treatment temperature was higher than 650 °C. The two different spalling failures were explained by weight gain, porosity and stress analyses. The heating rate had a significant effect. The bonding strength and hydrogen permeation of the TLC samples were also tested. Remaining at 650 °C for 40 h was proved to be an optimal crack-filling heat treatment process, considering the hydrogen resistance.

  6. Comparison of the effects of different heat treatment processes on rheological properties of cake and bread wheat flours.

    Science.gov (United States)

    Bucsella, Blanka; Takács, Ágnes; Vizer, Viktoria; Schwendener, Urs; Tömösközi, Sándor

    2016-01-01

    Dry and hydrothermal heat treatments are efficient for modifying the technological-functional and shelf-life properties of wheat milling products. Dry heat treatment process is commonly used to enhance the volume of cakes. Hydrothermal heat treatment makes wheat flours suitable as thickener agents. In this study, cake and bread wheat flours that differed in baking properties were exposed to dry (100 °C, 12 min) and hydrothermal (95 °C, 5 min, 5-20 l/h water) heat treatments. Rheological differences caused by the treatments were investigated in a diluted slurry and in a dough matrix. Dry heat treatment resulted in enhanced dough stability. This effect was significantly higher in the cake flour than the bread flour. Altered viscosity properties of the bread flour in the slurry matrix were also observed. The characteristics of hydrothermally treated samples showed matrix dependency: their viscosity increases in the slurry and decreases in the dough matrix. These results can support us to produce flour products with specific techno-functional properties. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Surface engineering and heat treatment

    International Nuclear Information System (INIS)

    Morton, P.H.

    1991-01-01

    This book is the proceedings of a Conference organised jointly by The Institute of Metals and The Centre for Exploitation of Science and Technology (CEST). It sets out to review this role and point the way to the future by collecting together a series of invited papers written by noted authorities in their fields. The opening review by CEST highlights the economic and industrial importance of Surface Engineering and is followed by a group of four articles devoted to specific branches of industry. Several technical papers then describe various aspects of the development of heat treatment over the last twenty-five years. These are followed by papers describing advances made possible by new technologies such as plasma, laser and ion beam. A separate abstract has been prepared for a paper on materials aspects of ion beam technology. (author)

  8. Expression analysis of nine small heat shock protein genes from Tamarix hispida in response to different abiotic stresses and abscisic acid treatment.

    Science.gov (United States)

    Yang, Guiyan; Wang, Yucheng; Zhang, Kaimin; Gao, Caiqiu

    2014-03-01

    Heat shock proteins (HSPs) play important roles in protecting plants against environmental stresses. Furthermore, small heat shock proteins (sHSPs) are the most ubiquitous HSP subgroup with molecular weights ranging from 15 to 42 kDa. In this study, nine sHSP genes (designated as ThsHSP1-9) were cloned from Tamarix hispida. Their expression patterns in response to cold, heat shock, NaCl, PEG and abscisic acid (ABA) treatments were investigated in the roots and leaves of T. hispida by real-time RT-PCR analysis. The results showed that most of the nine ThsHSP genes were expressed at higher levels in roots than in leaves under normal growth condition. All of ThsHSP genes were highly induced under conditions of cold (4 °C) and different heat shocks (36, 40, 44, 48 and 52 °C). Under NaCl stress, all nine ThsHSPs genes were up-regulated at least one stress time-point in both roots and leaves. Under PEG and ABA treatments, the nine ThsHSPs showed various expression patterns, indicating a complex regulation pathway among these genes. This study represents an important basis for the elucidation of ThsHSP gene function and provides essential information that can be used for stress tolerance genetic engineering in future studies.

  9. Impact of Surface Potential on Apatite Formation in Ti Alloys Subjected to Acid and Heat Treatments.

    Science.gov (United States)

    Yamaguchi, Seiji; Hashimoto, Hideki; Nakai, Ryusuke; Takadama, Hiroaki

    2017-09-24

    Titanium metal (Ti) and its alloys are widely used in orthopedic and dental fields. We have previously shown that acid and heat treatment was effective to introduce bone bonding, osteoconduction and osteoinduction on pure Ti. In the present study, acid and heat treatment with or without initial NaOH treatment was performed on typical Ti-based alloys used in orthopedic and dental fields. Dynamic movements of alloying elements were developed, which depended on the kind of treatment and type of alloy. It was found that the simple acid and heat treatment enriched/remained the alloying elements on Ti-6Al-4V, Ti-15Mo-5Zr-3Al and Ti-15Zr-4Nb-4Ta, resulting in neutral surface charges. Thus, the treated alloys did not form apatite in a simulated body fluid (SBF) within 3 days. In contrast, when the alloys were subjected to a NaOH treatment prior to an acid and heat treatment, alloying elements were selectively removed from the alloy surfaces. As a result, the treated alloys became positively charged, and formed apatite in SBF within 3 days. Thus, the treated alloys would be useful in orthopedic and dental fields since they form apatite even in a living body and bond to bone.

  10. Quality of mango nectar processed by high-pressure homogenization with optimized heat treatment.

    Science.gov (United States)

    Tribst, Alline Artigiani Lima; Franchi, Mark Alexandrow; de Massaguer, Pilar Rodriguez; Cristianini, Marcelo

    2011-03-01

    This work aimed to evaluate the effect of high-pressure homogenization (HPH) with heat shock on Aspergillus niger, vitamin C, and color of mango nectar. The nectar was processed at 200 MPa followed by heat shock, which was optimized by response surface methodology by using mango nectar ratio (45 to 70), heat time (10 to 20), and temperature (60 to 85 °C) as variables. The color of mango nectar and vitamin C retention were evaluated at the optimized treatments, that is, 200 MPa + 61.5 °C/20 min or 73.5 °C/10 min. The mathematical model indicates that heat shock time and temperature showed a positive effect in the mould inactivation, whereas increasing ratio resulted in a protective effect on A. niger. The optimized treatments did not increase the retention of vitamin C, but had positive effect for the nectar color, in particular for samples treated at 200 MPa + 61.5 °C/20 min. The results obtained in this study show that the conidia can be inactivated by applying HPH with heat shock, particularly to apply HPH as an option to pasteurize fruit nectar for industries.

  11. Heat-shock-induced enhanced reactivation of UV-irradiated Herpesvirus

    Energy Technology Data Exchange (ETDEWEB)

    Yager, J.D.; Zurlo, J.; Penn, A.L.

    1985-09-01

    The objective of this study was to compare the ability of heat shock (HS) with that of another type of cellular stress, UV irradiation, to cause the induction of enhanced viral reactivation, a process that may represent an SOS-type repair process in mammalian cells. These results indicate that, like UV irradiation, HS at levels inhibitory to cell growth induced enhanced viral reactivation in Vero cells. The results also suggest that at least two proteins in the HS protein family are not necessary for this response to occur. (Auth.). 27 refs.; 5 figs.

  12. Differential transcript induction of parsley pathogenesis-related proteins and of a small heat shock protein by ozone and heat shock

    International Nuclear Information System (INIS)

    Eckey-Kaltenbach, H.; Kiefer, E.; Grosskopf, E.; Ernst, D.; Sandermann, H. Jr

    1997-01-01

    Parsley (Petroselinum (crispum L.) is known to respond to pathogen attack by the synthesis of furanocoumarins and to UV irradiation by the synthesis of flavone glycosides whereas ozone treatment results in the induction of both pathways. A cDNA library from parsley plants was differentially screened using labelled reverse-transcribed poly(A)+ RNA isolated from ozone-treated parsley plants. This resulted in the isolation of 13 independent cDNA clones representing ozone-induced genes and of 11 cDNA clones representing ozone-repressed genes. DNA sequencing of several clones resulted in the identification of pathogenesis-related protein 1-3 (PR1-3), of a new member of PR1 cDNAs (PRI-4) and of a small heat shock protein (sHSP). Northern blot analyses showed a transient induction of the three mRNA species after ozone fumigation. In contrast, heat shock treatment of parsley plants resulted in an increase of sHSP mRNA whereas no increase for transcripts of PR1-3 and PR1-4 could be observed. This is the first characterized sHSP cDNA clone for plants induced by heat shock, as well as by oxidative stress caused by ozone. (author)

  13. Computational simulation of heat transfer in laser melted material flow

    International Nuclear Information System (INIS)

    Shankar, V.; Gnanamuthu, D.

    1986-01-01

    A computational procedure has been developed to study the heat transfer process in laser-melted material flow associated with surface heat treatment of metallic alloys to improve wear-and-tear and corrosion resistance. The time-dependent incompressible Navier-Stokes equations are solved, accounting for both convective and conductive heat transfer processes. The convection, induced by surface tension and high surface temperature gradients, sets up a counterrotating vortex flow within the molten pool. This recirculating material flow is responsible for determining the molten pool shape and the associated cooling rates which affect the solidifying material composition. The numerical method involves an implicit triple-approximate factorization scheme for the energy equation, and an explicit treatment for the momentum and the continuity equations. An experimental setup, using a continuous wave CO 2 laser beam as a heat source, has been carried out to generate data for validation of the computational model. Results in terms of the depth, width, and shape of the molten pool and the heat-affected zone for various power settings and shapes of the laser, and for various travel speeds of the workpiece, compare very well with experimental data. The presence of the surface tension-induced vortex flow is demonstrated

  14. Changes in Salicylic Acid and Antioxidants during Induced Thermotolerance in Mustard Seedlings

    Science.gov (United States)

    Dat, James F.; Foyer, Christine H.; Scott, Ian M.

    1998-01-01

    Heat-acclimation or salicylic acid (SA) treatments were previously shown to induce thermotolerance in mustard (Sinapis alba L.) seedlings from 1.5 to 4 h after treatment. In the present study we investigated changes in endogenous SA and antioxidants in relation to induced thermotolerance. Thirty minutes into a 1-h heat-acclimation treatment glucosylated SA had increased 5.5-fold and then declined during the next 6 h. Increases in free SA were smaller (2-fold) but significant. Changes in antioxidants showed the following similarities after either heat-acclimation or SA treatment. The reduced-to-oxidized ascorbate ratio was 5-fold lower than the controls 1 h after treatment but recovered by 2 h. The glutathione pool became slightly more oxidized from 2 h after treatment. Glutathione reductase activity was more than 50% higher during the first 2 h. Activities of dehydroascorbate reductase and monodehydroascorbate reductase decreased by at least 25% during the first 2 h but were 20% to 60% higher than the control levels after 3 to 6 h. One hour after heat acclimation ascorbate peroxidase activity was increased by 30%. Young leaves appeared to be better protected by antioxidant enzymes following heat acclimation than the cotyledons or stem. Changes in endogenous SA and antioxidants may be involved in heat acclimation. PMID:9847121

  15. On board short-time high temperature heat treatment of ballast water: a field trial under operational conditions.

    Science.gov (United States)

    Quilez-Badia, Gemma; McCollin, Tracy; Josefsen, Kjell D; Vourdachas, Anthony; Gill, Margaret E; Mesbahi, Ehsan; Frid, Chris L J

    2008-01-01

    A ballast water short-time high temperature heat treatment technique was applied on board a car-carrier during a voyage from Egypt to Belgium. Ballast water from three tanks was subjected for a few seconds to temperatures ranging from 55 degrees C to 80 degrees C. The water was heated using the vessel's heat exchanger steam and a second heat exchanger was used to pre-heat and cool down the water. The treatment was effective at causing mortality of bacteria, phytoplankton and zooplankton. The International Maritime Organization (IMO) standard was not agreed before this study was carried out, but comparing our results gives a broad indication that the IMO standard would have been met in some of the tests for the zooplankton, in all the tests for the phytoplankton; and probably on most occasions for the bacteria. Passing the water through the pump increased the kill rate but increasing the temperature above 55 degrees C did not improve the heat treatment's efficacy.

  16. Effect of heat treatment on interface driven magnetic properties of CoFe films

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Akhilesh Kr., E-mail: drakhintu@gmail.com; Hsu, Jen-Hwa

    2017-06-15

    Highlights: • Ta underlayer and cap layer dependent anisotropy nature in thin CoFe films. • Thin Ta layer induces the magnetization component along normal to the film plane. • Heat treatment and Ta layers driven surface morphology, roughness and grain size. • Roughness reduces more than an order of magnitude with 2 nm Ta cap layer. • H{sub C}, domain patterns and domain size depend on Ta layers and heat treatment. - Abstract: We report systematic studies on non-magnetic Ta underlayer and cap layer driven microstructural and magnetic properties at a wide temperature range for CoFe films. All the films were grown at room temperature and post annealed at different annealing temperatures (T{sub A} = 200 °C, 250 °C, 300 °C, 350 °C, 400 °C and 450 °C). The in-plane magnetic hysteresis (M–H) loops of 10 nm thick CoFe single layer films, grown directly on thermally oxidized Si substrate, exhibit anisotropic nature for T{sub A} above 250 °C. However, the CoFe (10 nm) films grown on the 5 nm thick Ta underlayer show reduced anisotropy. Moreover, with underlayer and cap layers (2 nm) the anisotropy is disappeared. The in-plane coercivity (H{sub C}) shows a strong variation with T{sub A}, underlayer and cap layers. H{sub C} increases significantly with Ta underlayer and cap layers. The out of plane M–H loops exhibit increase in the remanence magnetization and squareness with both Ta underlayer and cap layers due to transition of in-plane magnetization component to the out of plane direction. The atomic force microscopic observations revealed that grain/particle size and shape depend strongly on T{sub A} and Ta layers. Moreover, a large reduction in the surface roughness is observed with the Ta cap layer. The magnetic domain patterns depend on the T{sub A}, and Ta layers. However, for Ta/CoFe/Ta films no clear domains were observed for all the T{sub A}. Hence, the Ta cap layers not only protect the CoFe magnetic layer against the heat treatment, but also

  17. Effect of heat treatment on interface driven magnetic properties of CoFe films

    International Nuclear Information System (INIS)

    Singh, Akhilesh Kr.; Hsu, Jen-Hwa

    2017-01-01

    Highlights: • Ta underlayer and cap layer dependent anisotropy nature in thin CoFe films. • Thin Ta layer induces the magnetization component along normal to the film plane. • Heat treatment and Ta layers driven surface morphology, roughness and grain size. • Roughness reduces more than an order of magnitude with 2 nm Ta cap layer. • H C , domain patterns and domain size depend on Ta layers and heat treatment. - Abstract: We report systematic studies on non-magnetic Ta underlayer and cap layer driven microstructural and magnetic properties at a wide temperature range for CoFe films. All the films were grown at room temperature and post annealed at different annealing temperatures (T A = 200 °C, 250 °C, 300 °C, 350 °C, 400 °C and 450 °C). The in-plane magnetic hysteresis (M–H) loops of 10 nm thick CoFe single layer films, grown directly on thermally oxidized Si substrate, exhibit anisotropic nature for T A above 250 °C. However, the CoFe (10 nm) films grown on the 5 nm thick Ta underlayer show reduced anisotropy. Moreover, with underlayer and cap layers (2 nm) the anisotropy is disappeared. The in-plane coercivity (H C ) shows a strong variation with T A , underlayer and cap layers. H C increases significantly with Ta underlayer and cap layers. The out of plane M–H loops exhibit increase in the remanence magnetization and squareness with both Ta underlayer and cap layers due to transition of in-plane magnetization component to the out of plane direction. The atomic force microscopic observations revealed that grain/particle size and shape depend strongly on T A and Ta layers. Moreover, a large reduction in the surface roughness is observed with the Ta cap layer. The magnetic domain patterns depend on the T A , and Ta layers. However, for Ta/CoFe/Ta films no clear domains were observed for all the T A . Hence, the Ta cap layers not only protect the CoFe magnetic layer against the heat treatment, but also show a smooth surface at a wide

  18. Gas Furnace with Pulsed Feeding of the Heating Agent for Volume Precision Heat Treatment of CCM Rolls

    Science.gov (United States)

    Moroz, V. I.; Egorova, V. M.; Gusev, S. V.

    2001-05-01

    A standard chamber batch furnace of the Severstal' plant has been modified for precision heat treatment of CCM rolls. The certification tests of a charge of rolls from steel 24KhM1F have shown the technical and economical advantages of the new design.

  19. Resveratrol induces antioxidant and heat shock protein mRNA expression in response to heat stress in black-boned chickens.

    Science.gov (United States)

    Liu, L L; He, J H; Xie, H B; Yang, Y S; Li, J C; Zou, Y

    2014-01-01

    This study investigated the effects of dietary resveratrol at 0, 200, 400, or 600 mg/kg of diet on the performance, immune organ growth index, serum parameters, and expression levels of heat shock protein (Hsp) 27, Hsp70, and Hsp90 mRNA in the bursa of Fabricius, thymus, and spleen of 42-d-old female black-boned chickens exposed to heat stress at 37 ± 2°C for 15 d. The results showed that heat stress reduced daily feed intake and BW gain; decreased serum glutathione (GSH), growth hormone, and insulin-like growth factor-1 levels; and inhibited GSH peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities compared with birds subjected to thermo-neutral circumstances. Chickens that were fed diets supplemented with resveratrol exhibited a linear increase in feed intake and BW gain (P stress. In contrast, serum malonaldehyde concentrations were decreased (P stress also reduced (P stress and coincided with an increase in supplemental resveratrol levels. The expression of Hsp27, Hsp70, and Hsp90 mRNA in the bursa of Fabricius and spleen were increased (P stress compared with no heat stress. Resveratrol attenuated the heat stress-induced overexpression of Hsp27, Hsp70, and Hsp90 mRNA in the bursa of Fabricius and spleen and increased the low expression of Hsp27 and Hsp90 mRNA in thymus upon heat stress. The results suggest that supplemental resveratrol improves growth performance and reduces oxidative stress in heat-stressed black-boned chickens by increasing serum growth hormone concentrations and modulating the expression of heat shock genes in organs of the immune system.

  20. Formation of tRNA granules in the nucleus of heat-induced human cells

    International Nuclear Information System (INIS)

    Miyagawa, Ryu; Mizuno, Rie; Watanabe, Kazunori; Ijiri, Kenichi

    2012-01-01

    Highlights: ► tRNAs are tranlocated into the nucleus in heat-induced HeLa cells. ► tRNAs form the unique granules in the nucleus. ► tRNA ganules overlap with nuclear stress granules. -- Abstract: The stress response, which can trigger various physiological phenomena, is important for living organisms. For instance, a number of stress-induced granules such as P-body and stress granule have been identified. These granules are formed in the cytoplasm under stress conditions and are associated with translational inhibition and mRNA decay. In the nucleus, there is a focus named nuclear stress body (nSB) that distinguishes these structures from cytoplasmic stress granules. Many splicing factors and long non-coding RNA species localize in nSBs as a result of stress. Indeed, tRNAs respond to several kinds of stress such as heat, oxidation or starvation. Although nuclear accumulation of tRNAs occurs in starved Saccharomyces cerevisiae, this phenomenon is not found in mammalian cells. We observed that initiator tRNA Met (Meti) is actively translocated into the nucleus of human cells under heat stress. During this study, we identified unique granules of Meti that overlapped with nSBs. Similarly, elongator tRNA Met was translocated into the nucleus and formed granules during heat stress. Formation of tRNA granules is closely related to the translocation ratio. Then, all tRNAs may form the specific granules.

  1. Formation of tRNA granules in the nucleus of heat-induced human cells

    Energy Technology Data Exchange (ETDEWEB)

    Miyagawa, Ryu [Radioisotope Center, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Department of Biological Science, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654 (Japan); Mizuno, Rie [Radioisotope Center, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Watanabe, Kazunori, E-mail: watanabe@ric.u-tokyo.ac.jp [Radioisotope Center, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Ijiri, Kenichi [Radioisotope Center, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Department of Biological Science, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654 (Japan)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer tRNAs are tranlocated into the nucleus in heat-induced HeLa cells. Black-Right-Pointing-Pointer tRNAs form the unique granules in the nucleus. Black-Right-Pointing-Pointer tRNA ganules overlap with nuclear stress granules. -- Abstract: The stress response, which can trigger various physiological phenomena, is important for living organisms. For instance, a number of stress-induced granules such as P-body and stress granule have been identified. These granules are formed in the cytoplasm under stress conditions and are associated with translational inhibition and mRNA decay. In the nucleus, there is a focus named nuclear stress body (nSB) that distinguishes these structures from cytoplasmic stress granules. Many splicing factors and long non-coding RNA species localize in nSBs as a result of stress. Indeed, tRNAs respond to several kinds of stress such as heat, oxidation or starvation. Although nuclear accumulation of tRNAs occurs in starved Saccharomyces cerevisiae, this phenomenon is not found in mammalian cells. We observed that initiator tRNA{sup Met} (Meti) is actively translocated into the nucleus of human cells under heat stress. During this study, we identified unique granules of Meti that overlapped with nSBs. Similarly, elongator tRNA{sup Met} was translocated into the nucleus and formed granules during heat stress. Formation of tRNA granules is closely related to the translocation ratio. Then, all tRNAs may form the specific granules.

  2. 热处理与可持续发展%Heat Treatment and Sustainable Development

    Institute of Scientific and Technical Information of China (English)

    徐跃明; 樊东黎

    2001-01-01

    In the view point of sustainable development,there exist some serious problems,such as higher energy consumption,environmental pollution,oxidation and decarburization of steels,in the heat treatment industry of China.In order to keep the sustainable development of heat treatment industry in China,something must be done.First of all is to heighten sustainable development consciousness.At the same time,it is necessary to strengthen technology innovation and speed up improving traditional heat treatment industry with high technology,to develop the clean production of heat treatment and popularize the application of efficient,energy saving and none or less oxidation heat treatment technology.A great attention is still paid to the certification of ISO9000 and ISO14000 series standard and heat treatment industry standard to raise modernized and standard management level of enterprises.%从可持续发展的角度分析,我国热处理行业主要存在能耗高、环境污染严重、氧化脱碳严重3大问题。目前,热处理行业仍普遍存在节能环保意识不强,缺乏有效的管理措施,技术落后等现象。面对新的挑战,热处理要在21世纪得到持续发展,必须从“源消减”做起。首先要加强可持续发展的意识;加强技术创新,加快用高新技术改造传统热处理产业的步伐;积极发展热处理清洁生产,推广高效、节能、少无氧化热处理技术;重视ISO9000、ISO14000标准系列认证和行业达标验收工作,全面提高企业现代化、规范化管理水平。

  3. Effects of heat treatment on mechanical properties of h13 steel

    Science.gov (United States)

    Guanghua, Yan; Xinmin, Huang; Yanqing, Wang; Xingguo, Qin; Ming, Yang; Zuoming, Chu; Kang, Jin

    2010-12-01

    Heat treatment on the mechanical properties of H13 hot working die steel for die casting is discussed. The H13 steel for die casting was treated by different temperatures of vacuum quenching, tempering, and secondary tempering to investigate its mechanical properties. Strength, plasticity, hardness, and impact toughness of the H13 hot working die steel for die casting were measured. Microstructure, grain size, and carbide particle size after heat treatment have a great impact on the mechanical properties of H13 hot working die steel for die casting. The microstructure of the H13 was analyzed by scanning electron microscopy (SEM) and by a metallographic microscope. It is found that H13 exhibits excellent mechanical properties after vacuum quenching at 1050°C and twice tempering at 600°C.

  4. Design and performance of a new induction furnace for heat treatment of superconducting radiofrequency niobium cavities.

    Science.gov (United States)

    Dhakal, Pashupati; Ciovati, Gianluigi; Rigby, Wayne; Wallace, John; Myneni, Ganapati Rao

    2012-06-01

    Superconducting radio frequency (SRF) cavities made of high purity niobium (Nb) are the building blocks of many modern particle accelerators. The fabrication process includes several cycles of chemical and heat treatment at low (∼120 °C) and high (∼800 °C) temperatures. In this contribution, we describe the design and performance of an ultra-high-vacuum furnace which uses an induction heating system to heat treat SRF cavities. Cavities are heated by radiation from the Nb susceptor. By using an all-niobium hot zone, contamination of the Nb cavity by foreign elements during heat treatment is minimized and allows avoiding subsequent chemical etching. The furnace was operated up to 1400 °C with a maximum pressure of ∼1 × 10(-5) Torr and the maximum achievable temperature is estimated to be higher than 2000 °C. Initial results on the performance of a single cell 1.5 GHz cavity made of ingot Nb heat treated at 1200 °C using this new induction furnace and without subsequent chemical etching showed a reduction of the RF losses by a factor of ∼2 compared to cavities made of fine-grain Nb which underwent standard chemical and heat treatments.

  5. Photosynthetic responses to heat treatments at different temperatures and following recovery in grapevine (Vitis amurensis L.) leaves.

    Science.gov (United States)

    Luo, Hai-Bo; Ma, Ling; Xi, Hui-Feng; Duan, Wei; Li, Shao-Hua; Loescher, Wayne; Wang, Jun-Fang; Wang, Li-Jun

    2011-01-01

    The electron transport chain, Rubisco and stomatal conductance are important in photosynthesis. Little is known about their combined responses to heat treatment at different temperatures and following recovery in grapevines (Vitis spp.) which are often grown in climates with high temperatures. The electron transport function of photosystem II, the activation state of Rubisco and the influence of stomatal behavior were investigated in grapevine leaves during heat treatments and following recovery. High temperature treatments included 35, 40 and 45°C, with 25°C as the control and recovery temperature. Heat treatment at 35°C did not significantly (P>0.05) inhibit net photosynthetic rate (P(n)). However, with treatments at 40 and 45°C, P(n) was decreased, accompanied by an increase in substomatal CO(2) concentration (C(i)), decreases in stomatal conductance (g(s)) and the activation state of Rubisco, and inhibition of the donor side and the reaction center of PSII. The acceptor side of PSII was inhibited at 45°C but not at 40°C. When grape leaves recovered following heat treatment, P(n), g(s) and the activation state of Rubisco also increased, and the donor side and the reaction center of PSII recovered. The increase in P(n) during the recovery period following the second 45°C stress was slower than that following the 40°C stress, and these increases corresponded to the donor side of PSII and the activation state of Rubisco. Heat treatment at 35°C did not significantly (P>0.05) influence photosynthesis. The decrease of P(n) in grape leaves exposed to more severe heat stress (40 or 45°C) was mainly attributed to three factors: the activation state of Rubisco, the donor side and the reaction center of PSII. However, the increase of P(n) in grape leaves following heat stress was also associated with a stomatal response. The acceptor side of PSII in grape leaves was responsive but less sensitive to heat stress.

  6. Robust heat-inducible gene expression by two endogenous hsp70-derived promoters in transgenic Aedes aegypti

    Science.gov (United States)

    Carpenetti, Tiffany L. G.; Aryan, Azadeh; Myles, Kevin M.; Adelman, Zach N.

    2011-01-01

    Aedes aegypti is an important vector of the viruses that cause dengue fever, dengue hemorrhagic fever, and yellow fever. Reverse genetic approaches to the study of gene function in this mosquito have been limited by the lack of a robust inducible promoter to allow precise temporal control over a protein-encoding or hairpin RNA transgene. Likewise, investigations into the molecular and biochemical basis of vector competence would benefit from the ability to activate an anti-pathogen molecule at specific times during infection. We have characterized the ability of genomic sequences derived from two Ae. aegypti hsp70 genes to drive heat-inducible expression of a reporter in both transient and germline transformation contexts. AaHsp70-luciferase transcripts accumulated specifically after heat shock, and displayed a pattern of rapid induction and decay similar to endogenous AaHsp70 genes. Luciferase expression in transgenic Ae. aegypti increased by ∼25-50 fold in whole adults by four hours after heat-shock, with significant activity (∼20 fold) remaining at 24 hr. Heat-induced expression was even more dramatic in midgut tissues, with one strain showing a ∼2500-fold increase in luciferase activity. The AaHsp70 promoters described could be valuable for gene function studies as well as for the precise timing of the expression of anti-pathogen molecules. PMID:22142225

  7. Curie Temperature and Microstructural Changes Due to the Heating Treatment of Magnetic Amorphous Materials

    Directory of Open Access Journals (Sweden)

    Gondro J.

    2016-03-01

    Full Text Available Three distinct alloys: Fe86Zr7Nb1Cu1B5, Fe82Zr7Nb2Cu1B8, and Fe81Pt5Zr7Nb1Cu1B5 were characterized both magnetically and structurally. The samples, obtained with spinning roller method as a ribbons 3 mm in width and 20 μm thick, were investigated as-quenched and after each step of a multi steps heating treatment procedure. Each sample was annealed at four steps, fifteen minutes at every temperature, starting from 573K+600K up to +700K depending on type of alloy. Mössbauer spectroscopy data and transmission electron microscope (HRE M pictures confirmed that the as-quenched samples are fully amorphous. This is not changed after the first stages of treatment heating leads to a reduction of free volumes. The heating treatment has a great influence on the magnetic susceptibilities. The treatment up to 600K improves soft magnetic properties: an χ increase was observed, from about 400 to almost 1000 for the samples of alloys without Pt, and from about 200 to 450 at maximum, for the Fe81Pt5Zr7Nb1Cu1B5. Further heating, at more elevated temperatures, leads to magnetic hardening of the samples. Curie temperatures, established from the location of Hopkinson’s maxima on the χ(T curve are in very good agreement with those obtained from the data of specific magnetization, σ(T, measured in a field of 0.75T. As a critical parameter β was chosen to be equal 0.36 for these calculations, it confirmed that the alloys may be considered as ferromagnetic of Heisenberg type. Heating treatment resulted in decreasing of TC. These changes are within a range of several K.

  8. Effect of Stabilization Heat Treatment on Time-Dependent Polarization Losses in Sintered Nd-Fe-B Permanent Magnets

    Directory of Open Access Journals (Sweden)

    Tuominen S.

    2013-01-01

    Full Text Available Some companies in the motor and generator industry utilizing sintered NdFeB magnets have adopted pre-ageing heat treatment in order to improve the stability of the magnets. The parameters of this stabilization heat treatment are based mainly on assumptions rather than on any published research results. In this work, the effects of pre-ageing treatment on the time-dependent polarization losses of two different types of commercial sintered NdFeB magnets were studied. The material showing the squarer J(H curve did not benefit from the pre-ageing treatment, since it seems to be stable under a certain critical temperature. In contrast, a stabilizing effect was observed in the material showing rounder J(H curve. After the stabilization heat treatment, the polarization of the magnets was found to be at lower level, but unchanged over a certain period of time. The length of this period depends on the temperature and the duration of the pre-ageing treatment. In addition, our analysis reveals that the stabilization heat treatment performed in an open circuit condition does not stabilize the magnet uniformly.

  9. Regularities of texture formation in alloys undergoing phase transformations during heat treatment and plastic working

    International Nuclear Information System (INIS)

    Ageev, N.V.; Babarehko, A.A.

    1983-01-01

    Peculiarities of texture formation in metals undergoing phase transformations in the temperature range of heat treatment and hot working are investigated theoretically and experimentally. A low-temperature phase after hot working is shown to inherite a high-temperature phase texture due to definite orientation conformity during phase transformation. Strengthened heat and thermomechanical treatments, as a rule, do not destroy material texture but change it

  10. Surface chemistry of polyacrylonitrile- and rayon-based activated carbon fibers after post-heat treatment

    International Nuclear Information System (INIS)

    Chiang Yuchun; Lee, C.-Y.; Lee, H.-C.

    2007-01-01

    Polyacrylonitrile- and rayon-based activated carbon fibers (ACFs) subject to heat treatment were investigated by means of elemental analyzer, and X-ray photoelectron spectroscopy (XPS). The total ash content of all ACFs was also analyzed. The adsorption of benzene, carbon tetrachloride and water vapor on ACFs was determined to shed light on the role of surface chemistry on gas adsorption. Results show that different precursors resulted in various elemental compositions and imposed diverse influence upon surface functionalities after heat treatment. The surface of heat-treated ACFs became more graphitic and hydrophobic. Three distinct peaks due to C, N, and O atoms were identified by XPS, and the high-resolution revealed the existence of several surface functionalities. The presence of nitride-like species, aromatic N-imines, or chemisorbed nitrogen oxides was found to be of great advantage to adsorption of water vapor or benzene, but the pyridine-N was not. Unstable complexes on the surface would hinder the fibers from adsorption of carbon tetrachloride. The rise in total ash content or hydrogen composition was of benefit to the access of water vapor. Modifications of ACFs by heat treatment have effectively improved adsorption performance

  11. Heat treatment for improvement in lower temperature mechanical properties of 0.40 pct C-Cr-Mo ultrahigh strength steel

    Science.gov (United States)

    Tomita, Yoshiyuki; Okabayashi, Kunio

    1983-11-01

    In the previous paper, it was reported that isothermal heat treatment of a commercial Japanese 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel (AISI 4340 type) at 593 K for a short time followed by water quenching, in which a mixed structure of 25 vol pct lower bainite and 75 vol pct martensite is produced, results in the improvement of low temperature mechanical properties (287 to 123 K). The purpose of this paper is to study whether above new heat treatment will still be effective in commercial practice for improving low temperature mechanical properties of the ultrahigh strength steel when applied to a commercial Japanese 0.40 pct C-Cr-Mo ultrahigh strength steel which is economical because it lacks the expensive nickel component (AISI 4140 type). At and above 203 K this new heat treatment, as compared with the conventional 1133 K direct water quenching treatment, significantly improved the strength, tensile ductility, and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel. At and above 203 K the new heat treatment also produced superior fracture ductility and notch toughness results at similar strength levels as compared to those obtained by using γ α' repetitive heat treatment for the same steel. However, the new heat treatment remarkably decreased fracture ductility and notch toughness of the 0.40 pct C-Cr-Mo ultrahigh strength steel below 203 K, and thus no significant improvement in the mechanical properties was noticeable as compared with the properties produced by the conventional 1133 K direct water quenching treatment and the γ α' repetitive heat treatment. This contrasts with the fact that the new heat treatment, as compared with the conventional 1133 K direct water quenching treatment and the γ α' repetitive heat treatment, dramatically improved the notch toughness of the 0.40 pct C-Ni-Cr-Mo ultrahigh strength steel, providing a better combination of strength and ductility throughout the 287 to 123 K temperature range. The difference

  12. Hybrid fuzzy logic control of laser surface heat treatments

    International Nuclear Information System (INIS)

    Perez, Jose Antonio; Ocana, Jose Luis; Molpeceres, Carlos

    2007-01-01

    This paper presents an advanced hybrid fuzzy logic control system for laser surface heat treatments, which allows to increase significantly the uniformity and final quality of the obtained product, reducing the rejection rate and increasing the productivity and efficiency of the treatment. Basically, the proposed hybrid control structure combines a fuzzy logic controller, with a pure integral action, both fully decoupled, improving the performances of the process with a reasonable design cost, since the system nonlinearities are fully compensated by the fuzzy component of the controller, while the integral action contributes to eliminate the steady-state error

  13. Deep heat muscle treatment: A mathematical model - I

    International Nuclear Information System (INIS)

    Ogulu, A.; Bestman, A.R.

    1992-03-01

    The flow of blood during deep heat muscle treatment is studied in this paper. We model the blood vessel as a long tube in circular section whose radius varied slowly. Under the Boussinesq approximation, we seek asymptotic series expansions for the velocity components, temperature and pressure about a small parameter, ε, characterizing the radius variation. The study reveals mathematically why physicians recommend a hot bath for cuts and physiotherapists use ice packs for bruises. (author). 5 refs, 3 figs

  14. Involvement of DNA-PK and ATM in radiation- and heat-induced DNA damage recognition and apoptotic cell death

    International Nuclear Information System (INIS)

    Tomita, Masanori

    2010-01-01

    Exposure to ionizing radiation and hyperthermia results in important biological consequences, e.g. cell death, chromosomal aberrations, mutations, and DNA strand breaks. There is good evidence that the nucleus, specifically cellular DNA, is the principal target for radiation-induced cell lethality. DNA double-strand breaks (DSBs) are considered to be the most serious type of DNA damage induced by ionizing radiation. On the other hand, verifiable mechanisms which can lead to heat-induced cell death are damage to the plasma membrane and/or inactivation of heat-labile proteins caused by protein denaturation and subsequent aggregation. Recently, several reports have suggested that DSBs can be induced after hyperthermia because heat-induced phosphorylated histone H2AX (γ-H2AX) foci formation can be observed in several mammalian cell lines. In mammalian cells, DSBs are repaired primarily through two distinct and complementary mechanisms: non-homologous end joining (NHEJ), and homologous recombination (HR) or homology-directed repair (HDR). DNA-dependent protein kinase (DNA-PK) and ataxia-telangiectasia mutated (ATM) are key players in the initiation of DSB repair and phosphorylate and/or activate many substrates, including themselves. These phosphorylated substrates have important roles in the functioning of cell cycle checkpoints and in cell death, as well as in DSB repair. Apoptotic cell death is a crucial cell suicide mechanism during development and in the defense of homeostasis. If DSBs are unrepaired or misrepaired, apoptosis is a very important system which can protect an organism against carcinogenesis. This paper reviews recently obtained results and current topics concerning the role of DNA-PK and ATM in heat- or radiation-induced apoptotic cell death. (author)

  15. The Effect of Heat Treatment on the Pull-off Strength of Optionally Varnished Surfaces of Five Wood Materials

    Directory of Open Access Journals (Sweden)

    Musa Atar

    2015-09-01

    Full Text Available This study investigated the effects of heat treatment, following optional treatment with synthetic, water-based, and alkyd varnishes, on the pull-off strength of wooden materials sampled from oriental beech (Fagus orientalis L., oak (Quercus petraea Liebl., black poplar (Populus nigra L., pine (Pinus sylvestris L., and fir (Abies bornmulleriana M.. The test samples were subjected to heat treatment at temperatures of 165 °C and 175 °C for periods of 2 and 4 h with a total of 4 variations. With respect to the wood type, the samples of beech wood yielded the highest results for pull-off strength, while fir wood yielded the lowest. With respect to the varnish types, the highest pull-off strength was found in the samples of synthetic varnished beech (5,452 with a 37.2% improvement at 175 °C heat treatment for 4 h, while the lowest results were obtained in the samples of fir (0.991 with a 48.5% decrease at 175 °C heat treatment for 4 h. In conclusion, heat treatment significantly decreased the pull-off strength of the woods.

  16. Influence of Solution Heat Treatment on Structure and Mechanical Properties of ZnAl22Cu3 Alloy

    Directory of Open Access Journals (Sweden)

    Michalik R.

    2016-09-01

    Full Text Available The influence of solution heat treatment at 385°C over 10 h with cooling in water on the structure, hardness and strength of the ZnAl22Cu3 eutectoid alloy is presented in the paper. The eutectoid ZnAl22Cu3 alloy is characterized by a dendritic structure. Dendrites are composed of a supersaturated solid solution of Al in Zn. In the interdendritic spaces a eutectoid mixture is present, with an absence of the ε (CuZn4 phase. Solution heat treatment of the ZnAl22Cu3 alloy causes the occurrence of precipitates rich in Zn and Cu, possibly ε phase. Solution heat treatment at 385°C initially causes a significant decrease of the alloy hardness, although longer solution heat treatment causes a significant increase of the hardness as compared to the as-cast alloy.

  17. Novel Bioactive Titanate Layers Formed on Ti Metal and Its Alloys by Chemical Treatments

    Directory of Open Access Journals (Sweden)

    Tadashi Kokubo

    2009-12-01

    Full Text Available Sodium titanate formed on Ti metal by NaOH and heat treatments induces apatite formation on its surface in a body environment and bonds to living bone. These treatments have been applied to porous Ti metal in artificial hip joints, and have been used clinically in Japan since 2007. Calcium titanate formed on Ti-15Zr-4Nb-4Ta alloy by NaOH, CaCl2, heat, and water treatments induces apatite formation on its surface in a body environment. Titanium oxide formed on porous Ti metal by NaOH, HCl, and heat treatments exhibits osteoinductivity as well as osteoconductivity. This is now under clinical tests for application to a spinal fusion device.

  18. Prevention and Treatment of Noise-Induced Tinnitus

    Science.gov (United States)

    2014-09-01

    Tinnitus PRINCIPAL INVESTIGATOR: Dr. Richard A. Altschuler CONTRACTING ORGANIZATION: University of Michigan REPORT DATE: 2014...3 Ju 2014 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Prevention and Treatment of Noise-Induced Tinnitus 5b. GRANT NUMBER 5c. PROGRAM...prevent or treat noise induced tinnitus . Our studies showed a military relevant small arms fire-like noise will induce tinnitus in approximately 33

  19. Effects of post heat-treatment on surface characteristics and adhesive bonding performance of medium density fiberboard

    Science.gov (United States)

    Nadir Ayrilimis; Jerrold E. Winandy

    2009-01-01

    A series of commercially manufactured medium density fiberboard (MDF) panels were exposed to a post-manufacture heat-treatment at various temperatures and durations using a hot press and just enough pressure to ensure firm contact between the panel and the press platens. Post-manufacture heat-treatment improved surface roughness of the exterior MDF panels. Panels...

  20. Treatment of the loss of ultimate heat sink initiating events in the IRSN level 1 PSA

    International Nuclear Information System (INIS)

    Dupuy, Patricia; Georgescu, Gabriel; Corenwinder, Francois

    2014-01-01

    The total loss of the ultimate heat sink is an initiating event which, even it is mainly of external origin, has been considered in the frame of internal events Level 1 PSA by IRSN. The on-going actions on the development of external hazards PSA and the recent incident of loss of the heat sink induced by the ingress of vegetable matter that occurred in France in 2009 have pointed out the need to improve the modeling of the loss of the heat sink initiating event and sequences to better take into account the fact that this loss may be induced by external hazards and thus affect all the site units. The paper presents the historical steps of the modeling of the total loss of the heat sink, the safety stakes of this modeling, the main assumptions used by IRSN in the associated PSA for the 900 MWe reactors and the results obtained. The total loss of the heat sink was not initially addressed in the safety demonstration of French NPPs. On the basis of the insights of the first probabilistic assessments performed in the 80's, the risks associated to this 'multiple failure situation' turned out to be very significant and design and organisational improvements were implemented on the plants. Reviews of the characterization of external hazards and of their consequences on the installations and French operating feedback have revealed that extreme hazards may induce a total loss of the heat sink. Moreover, the accident that occurred at Fukushima in 2011 has pointed out the risk of such a loss of long duration at all site units in case of extreme hazards. In this context, it seems relevant to further improve the modelling of the total loss of the heat sink by considering the external hazards that may cause this loss. In a first step, IRSN has improved the assumptions and data used in the loss of the heat sink PSA model, in particular by considering that such a loss may affect all the site units. The next challenge will be the deeper analysis of the impact of external hazards on

  1. On the conjoint influence of heat treatment and lithium content on microstructure and mechanical properties of A380 aluminum alloy

    International Nuclear Information System (INIS)

    Karamouz, Mostafa; Azarbarmas, Mortaza; Emamy, Masoud

    2014-01-01

    Highlights: • T4 heat treatment and the addition of Li modify the microstructure of alloy. • Heat treatment improves the tensile properties of non-modified and modified alloys. • Fracture surfaces of modified specimens had more ductile dimples than base alloys. - Abstract: In this study, the effects of a T4 heat treatment on the microstructure and tensile properties of an A380 aluminum alloy with and without lithium (Li) additions have been investigated. Microstructural examination was carried out using optical and scanning electron microscopy, image analysis, and X-ray diffraction (XRD) analysis methods. The results showed that when the T4 heat treatment was applied, spheroidized eutectic Si particles and fragmented β-phase particles were formed. The influence of the heat treatment on the aspect ratio and average length of Si and β phases in a non-modified alloy was more noticeable than in the Li-modified. Significant improvements in tensile properties were also observed in heat-treated samples. Additionally, a fractographical analysis showed that the fracture surfaces of the Li-modified specimens with and without heat treatment had more ductile dimple and fewer brittle cleavage surfaces

  2. Prostaglandin E synthase interacts with inducible heat shock protein 70 after heat stress in bovine primary dermal fibroblast cells.

    Science.gov (United States)

    Richter, Constanze; Viergutz, Torsten; Schwerin, Manfred; Weitzel, Joachim M

    2015-01-01

    Exposure to heat stress in dairy cows leads to undesired side effects that are reflected by complex alterations in endocrine parameters, such as reduced progesterone, estradiol, and thyroid hormone concentrations. These endocrine maladaptation leads to failure to resume cyclicity, a poor uterine environment and inappropriate immune responses in postpartum dairy cows. Prostaglandins (PG's) are lipid mediators, which serve as signal molecules in response to various external stimuli as well as to cell-specific internal signal molecules. A central role in PG synthesis plays prostaglandin E synthase (PGES) that catalyzes the isomerization of PGH2 to PGE2 .The present study was conducted to investigate heat stress associated PGES expression. Expression of PGES and inducible heat shock protein 70 (HSP70), as a putative chaperonic protein, was studied in bovine primary fibroblasts under different heat shock conditions. Bovine primary fibroblasts produce PGE2 at homoiothermical norm temperature (38.5°C in bovine), but reduce PGE2 production rates under extreme heat stress (at 45°C for 6 h). By contrast, PGE2 production rates are maintained after a milder heat stress (at 41.5°C for 6 h). PGE2 synthesis is abolished by application of cyclooxygenase inhibitor indomethacin, indicating de novo synthesis. Heat stress increases HSP70 but not PGES protein concentrations. HSP70 physically interacts with PGES and the PGES-HSP70 complex did not dissociate upon heat stress at 45°C even after returning the cells to 37°C. The PGE2 production negatively correlates with the portion of PGES-HSP70 complex. These results suggest a protein interaction between HSP70 and PGES in dermal fibroblast cells. Blockage of PGES protein by HSP70 seems to interfere with the regulatory processes essential for cellular adaptive protection. © 2014 International Society for Advancement of Cytometry. © 2014 International Society for Advancement of Cytometry.

  3. Heat treatment effect on the properties of the EhP767 maraging steel welded joints

    International Nuclear Information System (INIS)

    Taver, E.I.; Piskarev, M.N.; Yushchenko, K.A.; Pustovit, A.I.; Anisimova, M.S.

    1977-01-01

    Heat treatment effect on properties of welded joints of maraging 03Kh13N4K13M3T (EhP767) steel with yield strength over 150 kgs/mm 2 has been investigated. It is shown, that change in impact strength of aged joints at - 196 deg C depends on the amount of residual austenite and grain size. To stabilize 20-40 % residual austenite heat treatment regimes have been developed. Recommended are quenching at 1030-1050 deg C, sub-zero treatment and aging at 520 deg C for 16 hrs

  4. Direct measurements of sample heating by a laser-induced air plasma in pre-ablation spark dual-pulse laser-induced breakdown spectroscopy (LIBS).

    Science.gov (United States)

    Register, Janna; Scaffidi, Jonathan; Angel, S Michael

    2012-08-01

    Direct measurements of temperature changes were made using small thermocouples (TC), placed near a laser-induced air plasma. Temperature changes up to ~500 °C were observed. From the measured temperature changes, estimates were made of the amount of heat absorbed per unit area. This allowed calculations to be made of the surface temperature, as a function of time, of a sample heated by the air plasma that is generated during orthogonal pre-ablation spark dual-pulse (DP) LIBS measurements. In separate experiments, single-pulse (SP) LIBS emission and sample ablation rate measurements were performed on nickel at sample temperatures ranging from room temperature to the maximum surface temperature that was calculated using the TC measurement results (500 °C). A small, but real sample temperature-dependent increase in both SP LIBS emission and the rate of sample ablation was found for nickel samples heated up to 500 °C. Comparison of DP LIBS emission enhancement values for bulk nickel samples at room temperature versus the enhanced SP LIBS emission and sample ablation rates observed as a function of increasing sample temperature suggests that sample heating by the laser-induced air plasma plays only a minor role in DP LIBS emission enhancement.

  5. Variation of Mechanical Properties of High RRR And Reactor Grade Niobium With Heat Treatments

    Energy Technology Data Exchange (ETDEWEB)

    Ganapati Myneni; H. Umezawa

    2003-06-01

    Superconducting rf cavities used as accelerating structures in particle accelerators are made from high purity niobium with residual resistance ratios greater than 250. Reactor grade niobium is also used to make wave-guide and/or end group components for these accelerating structures. The major impurities in this type of niobium are interstitially dissolved gases such as hydrogen, nitrogen, and oxygen in addition to carbon. After fabricating the niobium accelerating structures, they are subjected to heat treatments for several hours in vacuum at temperatures of up to 900 C for degassing hydrogen or up to 1400 C for improving the thermal conductivity of niobium considerably. These heat treatments are affecting the mechanical properties of niobium drastically. In this paper the variation of the mechanical properties of high purity and reactor grade niobium with heat treatments in a vacuum of {approx} 10{sup -6} Torr and temperatures from 600 C to 1250 C for periods of 10 to 6 hours are presented.

  6. Effects of heat treatment conditions on microstructure and mechanical properties of AISI 420 steel

    Energy Technology Data Exchange (ETDEWEB)

    Scheuer, C.J.; Fraga, R.A.; Cardoso, R.P.; Brunatto, S.F. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Departamento de Engenharia Mecanica. Grupo de Tecnologia de Fabricacao Assistida por Plasma e Metalurgia do Po

    2014-07-01

    The cycle control of heat treatments, on the quenching and tempering operation of AISI 420 stainless steel, is essential for improved material performance. The adequate choice of heat treatment parameters, can lead an optimization on its mechanical properties and corrosion resistance. Thus, this paper aims to investigate the effects of quenchants medium, and austenitizing and tempering temperatures, on the microstructure and mechanical properties of AISI 420 steel. Different heat treatments cycles were studied: 1) samples were austenitized at 1050°C and water, oil and air quenched; 2) samples were austenitized at range temperatures of 950-1050°C and oil quenched; and 3) as-quenched samples were tempering at range temperatures of 400-500°C. Treated samples were characterized by optical microscopy, X-ray diffractometry and hardness measurements. The samples hardness increases with increasing cooling rate (water > oil > air quenched). Water quenched samples presented crack after cooling to room temperature. Samples hardness also increases with austenitizing temperature increasing, and decreases with increasing tempering temperature. (author)

  7. ANALYSIS OF PITTING CORROSION ON AN INCONEL 718 ALLOY SUBMITTED TO AGING HEAT TREATMENT

    Directory of Open Access Journals (Sweden)

    Felipe Rocha Caliari

    2014-10-01

    Full Text Available Inconel 718 is one of the most important superalloys, and it is mainly used in the aerospace field on account of its high mechanical strength, good resistance to fatigue and creep, good corrosion resistance and ability to operate continuously at elevated temperatures. In this work the resistance to pitting corrosion of a superalloy, Inconel 718, is analyzed before and after double aging heat treatment. The used heat treatment increases the creep resistance of the alloy, which usually is used up to 0.6 Tm. Samples were subjected to pitting corrosion tests in chloride-containing aqueous solution, according to ASTM-F746-04 and the procedure described by Yashiro et al. The results of these trials show that after heat treatment the superalloy presents higher corrosion resistance, i.e., the pitting corrosion currents of the as received surfaces are about 6 (six times bigger (~0.15 mA than those of double aged surfaces (~0.025 mA.

  8. Dissecting the Biochemical and Transcriptomic Effects of a Locally Applied Heat Treatment on Developing Cabernet Sauvignon Grape Berries.

    Science.gov (United States)

    Lecourieux, Fatma; Kappel, Christian; Pieri, Philippe; Charon, Justine; Pillet, Jérémy; Hilbert, Ghislaine; Renaud, Christel; Gomès, Eric; Delrot, Serge; Lecourieux, David

    2017-01-01

    Reproductive development of grapevine and berry composition are both strongly influenced by temperature. To date, the molecular mechanisms involved in grapevine berries response to high temperatures are poorly understood. Unlike recent data that addressed the effects on berry development of elevated temperatures applied at the whole plant level, the present work particularly focuses on the fruit responses triggered by direct exposure to heat treatment (HT). In the context of climate change, this work focusing on temperature effect at the microclimate level is of particular interest as it can help to better understand the consequences of leaf removal (a common viticultural practice) on berry development. HT (+ 8°C) was locally applied to clusters from Cabernet Sauvignon fruiting cuttings at three different developmental stages (middle green, veraison and middle ripening). Samples were collected 1, 7, and 14 days after treatment and used for metabolic and transcriptomic analyses. The results showed dramatic and specific biochemical and transcriptomic changes in heat exposed berries, depending on the developmental stage and the stress duration. When applied at the herbaceous stage, HT delayed the onset of veraison. Heating also strongly altered the berry concentration of amino acids and organic acids (e.g., phenylalanine, γ-aminobutyric acid and malate) and decreased the anthocyanin content at maturity. These physiological alterations could be partly explained by the deep remodeling of transcriptome in heated berries. More than 7000 genes were deregulated in at least one of the nine experimental conditions. The most affected processes belong to the categories "stress responses," "protein metabolism" and "secondary metabolism," highlighting the intrinsic capacity of grape berries to perceive HT and to build adaptive responses. Additionally, important changes in processes related to "transport," "hormone" and "cell wall" might contribute to the postponing of veraison

  9. Enhancing the mechanical properties of electrospun polyester mats by heat treatment

    Directory of Open Access Journals (Sweden)

    M. Kancheva

    2015-01-01

    Full Text Available Microfibrous materials with a targeted design based on poly(L-lactic acid (PLA and poly(ε-caprolactone (PCL were prepared by electrospinning and by combining electrospinning and electrospraying. Several approaches were used: (i electrospinning of a common solution of the two polymers, (ii simultaneous electrospinning of two separate solutions of PLA and PCL, (iii electrospinning of PLA solution in conjunction with electrospraying of PCL solution, and (iv alternating layer-by-layer deposition by electrospinning of separate PLA and PCL solutions. The mats were heated at the melting temperature of PCL (60°", thus achieving melting of PCL fibers/particles and thermal sealing of the fibers. The mats subjected to thermal treatment were characterized by greater mean fiber diameters and reduced values of the water contact angle compared to the pristine mats. Heat treatment of the mats affected their thermal stability and led to an increase in the crystallinity degree of PLA incorporated in the mats, whereas that of PCL was reduced. All mats were characterized by enhanced mechanical properties after thermal treatment as compared to the non-treated fibrous materials.

  10. Biochemical changes in full fat rice bran stabilized through microwave heating and irradiation treatment

    International Nuclear Information System (INIS)

    El-Niely, H.F.; Abaullah, M.I.

    2007-01-01

    The effect of microwave heating and irradiation treatments on proximate composition, lipoxygenase (LOX) activity, free fatty acid (FFA) and fatty acids profile of full fat rice bran were examined. Full fat raw rice bran (FRB) (82.7 g / kg moisture content) was heated in microwave oven at 850 W for up to 4 min or exposed to gamma irradiation up to 25 KGy then packed in polyethylene bags and stored at room temperature for 6 months. Water, protein, fat, ash and crude fiber contents did not change significantly in raw, microwave heated and irradiated samples before and after storage. An exception for this general observation was observed for the moisture content of FRB processed through microwave heating where heating FRB for 4 min dropped the level of moisture to 64.3 g / kg at zero time. Storage of both raw and processed samples had significant (P<0.05) effects on LOX activity. LOX activity of raw samples was significantly increased from its initial value by 43.5% after storage for six months. Microwave heat and irradiated samples showed deactivated LOX and samples exhibited significant changes in LOX activity could be due to treatment dosage. Meanwhile, significant change in LOX activity was observed in processed samples stored for six months. Minor changes were observed due to applied processing methods on FFA and fatty acids composition of full fat rice bran before and after storage. The results suggested that microwave heated or irradiated full fat rice bran packed in polyethylene bags can be stored at room temperature for six months without adverse effect on proximate, fatty acid composition quality and could prevent oxidative and hydrolytic rancidity. However, gamma irradiation treatment at 25 KGy was more effective in this respect. Therefore, it could be concluded that gamma irradiation contributed to optimal processing conditions for FRB stabilization

  11. Heat-induced symmetry breaking in ant (Hymenoptera: Formicidae escape behavior.

    Directory of Open Access Journals (Sweden)

    Yuan-Kai Chung

    Full Text Available The collective egress of social insects is important in dangerous situations such as natural disasters or enemy attacks. Some studies have described the phenomenon of symmetry breaking in ants, with two exits induced by a repellent. However, whether symmetry breaking occurs under high temperature conditions, which are a common abiotic stress, remains unknown. In our study, we deposited a group of Polyrhachis dives ants on a heated platform and counted the number of escaping ants with two identical exits. We discovered that ants asymmetrically escaped through two exits when the temperature of the heated platform was >32.75°C. The degree of asymmetry increased linearly with the temperature of the platform. Furthermore, the higher the temperature of heated platform was, the more ants escaped from the heated platform. However, the number of escaping ants decreased for 3 min when the temperature was higher than the critical thermal limit (39.46°C, which is the threshold for ants to endure high temperature without a loss of performance. Moreover, the ants tended to form small groups to escape from the thermal stress. A preparatory formation of ant grouping was observed before they reached the exit, indicating that the ants actively clustered rather than accidentally gathered at the exits to escape. We suggest that a combination of individual and grouping ants may help to optimize the likelihood of survival during evacuation.

  12. Sour gas injection for use with in situ heat treatment

    Science.gov (United States)

    Fowler, Thomas David [Houston, TX

    2009-11-03

    Systems, methods, and heaters for treating a subsurface formation are described herein. At least one method for providing acidic gas to a subsurface formation is described herein. The method may include providing heat from one or more heaters to a portion of a subsurface formation; producing fluids that include one or more acidic gases from the formation using a heat treatment process. At least a portion of one of the acidic gases may be introduced into the formation, or into another formation, through one or more wellbores at a pressure below a lithostatic pressure of the formation in which the acidic gas is introduced.

  13. New method of processing heat treatment experiments with numerical simulation support

    Science.gov (United States)

    Kik, T.; Moravec, J.; Novakova, I.

    2017-08-01

    In this work, benefits of combining modern software for numerical simulations of welding processes with laboratory research was described. Proposed new method of processing heat treatment experiments leading to obtaining relevant input data for numerical simulations of heat treatment of large parts was presented. It is now possible, by using experiments on small tested samples, to simulate cooling conditions comparable with cooling of bigger parts. Results from this method of testing makes current boundary conditions during real cooling process more accurate, but also can be used for improvement of software databases and optimization of a computational models. The point is to precise the computation of temperature fields for large scale hardening parts based on new method of temperature dependence determination of the heat transfer coefficient into hardening media for the particular material, defined maximal thickness of processed part and cooling conditions. In the paper we will also present an example of the comparison standard and modified (according to newly suggested methodology) heat transfer coefficient data’s and theirs influence on the simulation results. It shows how even the small changes influence mainly on distribution of temperature, metallurgical phases, hardness and stresses distribution. By this experiment it is also possible to obtain not only input data and data enabling optimization of computational model but at the same time also verification data. The greatest advantage of described method is independence of used cooling media type.

  14. Effect of Heat Treatment on Microstructure and Impact Toughness of Ti-6Al-4V Manufactured by Selective Laser Melting Process

    Directory of Open Access Journals (Sweden)

    Lee K.-A.

    2017-06-01

    Full Text Available This study manufactured Ti-6Al-4V alloy using one of the powder bed fusion 3D-printing processes, selective laser melting, and investigated the effect of heat treatment (650°C/3hrs on microstructure and impact toughness of the material. Initial microstructural observation identified prior-β grain along the building direction before and after heat treatment. In addition, the material formed a fully martensite structure before heat treatment, and after heat treatment, α and β phase were formed simultaneously. Charpy impact tests were conducted. The average impact energy measured as 6.0 J before heat treatment, and after heat treatment, the average impact energy increased by approximately 20% to 7.3 J. Fracture surface observation after the impact test showed that both alloys had brittle characteristics on macro levels, but showed ductile fracture characteristics and dimples at micro levels.

  15. The Through Process Simulation of Mold filling, Solidification, and Heat Treatment of the Al Alloy Bending Beam Low-pressure Casting

    International Nuclear Information System (INIS)

    Yin, Yajun; Guo, Zhao; Wang, Huan; Liao, Dunming; Chen, Tao; Zhou, Jianxin

    2015-01-01

    The research on the simulation for the through process of low-pressure casting and heat treatment is conducive to combine information technology and advanced casting technology, which will help to predict the defects and mechanical properties of the castings in the through process. In this paper, we focus on the simulation for through process of low-pressure casting and heat treatment of ZL114A Bending beam. Firstly, we analyzethe distribution of the shrinkage and porosities in filling and solidification process, and simulate the distribution of stress and strain in the late solidification of casting. Then, the numerical simulation of heat treatment process for ZL114A Bending beam is realized according to the heat treatment parameters and the corresponding simulation results of temperature field, stress, strain, and aging performance are given. Finally, we verify that simulation platform for the through process of low-pressure casting and heat treatment can serve the production practice perfectly and provide technical guidance and process optimization for the through process of low-pressure casting and heat treatment. (paper)

  16. Heat treatment effects on the surface chemisorption behavior of strained uranium: The H2O/U reaction

    International Nuclear Information System (INIS)

    Tiferet, E.; Mintz, M.H.; Zalkind, S.; Jacob, I.; Shamir, N.

    2007-01-01

    The initial interaction of H 2 O vapor with polycrystalline uranium surfaces was studied with samples initially strained, then strain relieved by heat treatments, performed in the temperature range up to ∼650 K. The chemisorption characteristics of these surfaces were studied by a combination of direct recoils spectrometry and X-ray photoelectron spectroscopy. X-ray diffraction measurements were used to determine the level of strain relief induced by each of the heat treatments. For all the samples, full water dissociation on the metal surface is observed. The reactivity of the samples towards water is clearly strain dependent, with the sticking coefficient decreasing as strain is relieved. It also seems that for strained samples the initial growth of the oxide is mostly inwards, while for the more relaxed samples lateral growth is dominant. Two interesting phenomena were observed for specific samples. For the 420 K relieved sample, partial dissociation process is observed on top of the forming oxide, in contrast to the full dissociation observed for the other samples. For the ∼650 K relieved sample, clustering of the adsorbed hydrogen atoms (resulted by water dissociation) on the metal surface is observed, in contrast to the homogeneous dispersion of H, occurring on the surface of all other samples. These two phenomena will further be studied in conjunction with microscopic metallurgical observations

  17. The heat treatment of steel. A mathematical control problem

    Energy Technology Data Exchange (ETDEWEB)

    Hoemberg, Dietmar; Kern, Daniela

    2009-07-21

    The goal of this paper is to show how the heat treatment of steel can be modelled in terms of a mathematical optimal control problem. The approach is applied to laser surface hardening and the cooling of a steel slab including mechanical effects. Finally, it is shown how the results can be utilized in industrial practice by a coupling with machine-based control. (orig.)

  18. THE EFFECT OF HEAT TREATMENT ON THE CHEMICAL AND COLOR CHANGE OF BLACK LOCUST (ROBINIA PSEUDOACACIA WOOD FLOUR

    Directory of Open Access Journals (Sweden)

    Yao Chen,

    2012-01-01

    Full Text Available The aim of this study was to investigate the effects of oxygen and moisture content (MC on the chemical and color changes of black locust (Robinia pseudoacacia wood during heat treatment. The wood flour was conditioned to different initial MCs and heated for 24 h at a constant temperature of 120ºC in either oxygen or nitrogen atmosphere. The pH values and chromaticity indexes were examined. Diffuse reflectance UV-Vis (DRUV and Fourier transform infrared (FTIR spectra were used to characterize the changes of chromophores upon heating. The study demonstrated that the pH values decreased after heat treatment, and it was lower when the heat treated was in oxygen than in nitrogen. The L* decreased significantly, while a* and b* increased. The total color difference ΔE* increased with increasing initial MC until a plateau was reached after 30% MC. The color change was greater in oxygen than in nitrogen. The hydroxyl groups decreased after heat treatment. The releases of acid and formation of quinoid compounds and carboxylic groups during heat treatment were confirmed. Discoloration of wood is due mainly to the condensation and oxidation reactions, which are accelerated by oxygen. Higher MCs are required to obtain the greatest color change of wood in inert atmosphere.

  19. Effect of Post-Weld Heat Treatment on Creep Rupture Properties of Grade 91 Steel Heavy Section Welds

    Energy Technology Data Exchange (ETDEWEB)

    Li, Leijun

    2012-11-02

    This project will conduct a systematic metallurgical study on the effect of post-weld heat treatment (PWHT) on the creep rupture properties of P91 heavy section welds. The objective is to develop a technical guide for selecting PWHT parameters, and to predict expected creep-rupture life based on the selection of heat treatment parameters. The project consists of four interdependent tasks: Experimentally and numerically characterize the temperature fields of typical post-weld heat treatment procedures for various weld and joint configurations to be used in Gen IV systems. Characterize the microstructure of various regions, including the weld fusion zone, coarse-grain heat-affected zone, and fine-grain heat affected zone, in the welds that underwent the various welding and PWHT thermal histories. Conduct creep and creep-rupture testing of coupons extracted from actual and physically simulated welds. Establish the relationship among PWHT parameters, thermal histories, microstructure, creep, and creep-rupture properties.

  20. Influence of sub-solvus solution heat treatment on γ′ morphological instability in a new Ni–Cr–Co-based powder metallurgy superalloy

    International Nuclear Information System (INIS)

    Yang, W.P.; Liu, G.Q.; Wu, K.; Hu, B.F.

    2014-01-01

    Highlights: • A special γ′ morphological instability in a new Ni–Cr–Co-based P/M superalloy was studied. • Three heat treatments were applied to the alloy and microstructures were observed. • Microstructure of the alloy was homogenized by sub-solvus solution heat treatment. • Sub-solvus solution heat treatment influences morphology of γ′ fan-type structures. • Sub-solvus solution heat treatment makes γ′ fan-type structures regular and stable. -- Abstract: The influence of the sub-solvus solution heat treatment on the microstructure, especially the γ′ morphology (γ′ fan-type structure), and microhardness of a new Ni–Cr–Co-based powder metallurgy superalloy was studied by means of field emission scanning electron microscopy (FESEM) and microhardness testing. The results show that sub-solvus solution heat treatment changes the microstructure of an as-forged alloy. It makes large primary γ′ phases at grain boundaries smaller and the distribution of secondary γ′ phases in the interior of the grains more homogeneous. Moreover, the grain boundaries widen because of the supplementary precipitate. The sub-solvus solution heat treatment before the super-solvus solution heat treatment does not change nucleation sites of the γ′ fan-type structures which precipitate during the super-solvus solution heat treatment. However, it influences the morphology of γ′ fan-type structures. Length distribution of the secondary γ′ dendrites in fan-type structures changes from a bimodal to a unimodal distribution, which means the lengths of the secondary γ′ dendrites become more uniform. Applying a sub-solvus solution heat treatment after the super-solvus solution heat treatment causes the secondary γ′ dendrites to be broken off in the fan-type structures and a refinement of the γ′ phases, and this improves stability of the γ′ phases