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Sample records for survival 90-kda heat

  1. Survival tactics within thermally-challenging roosts: heat tolerance ...

    African Journals Online (AJOL)

    Survival tactics within thermally-challenging roosts: heat tolerance and cold sensitivity in the Angolan free-tailed bat, Mops condylurus. ... This presumably allowed them to minimize energy costs of thermoregulation without compromising reproductive activity or their ability to avoid predators. Bats displayed pronounced heat ...

  2. Heat Survival and Phenotype Microarray Profiling of Salmonella Typhimurium Mutants.

    Science.gov (United States)

    Dawoud, Turki M; Khatiwara, Anita; Park, Si Hong; Davis, Morgan L; Baker, Christopher A; Ricke, Steven C; Kwon, Young Min

    2017-02-01

    Contamination of food products by pathogenic microorganisms continues to be a major public health and food industry concern. Non-typhoidal Salmonella species have led to numerous outbreaks associated with various foods. A wide variety of methods have been applied and introduced for treatment of fresh foods to eliminate pathogenic as well as spoilage microorganisms. Salmonella can become exposed to elevated temperatures while associated with hosts such as poultry. In addition, heat treatment is also applied at various stages of processing to retain the shelf life of food products. Despite this, these microorganisms may overcome exposure to such treatments through the efficient expression of stress response mechanisms and result in illness following consumption. Thermal stress induces a range of destructive exposures to bacterial cells such as protein damage and DNA damage caused by reactive oxygen species. In this study, we chose three genes (∆recD, ∆STM14_5307, and ∆aroD) associated with conditionally essential genes required for different aspects of optimal growth at 42 °C and evaluated the responses of wild type and mutant Salmonella Typhimurium strains to uncover potential mechanisms that may enable survival and resistance under thermal stress. The RecBCD complex that initiates repair of double-stranded DNA breaks through homologous recombination. STM14_5307 is a transcriptional regulator involved in stationary phase growth and inositol metabolism. The gene aroD is involved in metabolism and stationary phase growth. These strains were characterized via high throughput phenotypic profiling in response to two different growth temperatures (37 °C (human host temperature) and 42 °C (poultry host temperature)). The ∆aroD strain exhibited the highest sensitivity to the various temperatures followed by the ∆recD and ∆STM14_5307 strains, respectively. Achieving more understanding of the molecular mechanisms of heat survival may lead to the development

  3. Heat shock genes–integrating cell survival and death

    Indian Academy of Sciences (India)

    2007-03-22

    Mar 22, 2007 ... Heat shock induced gene expression and other cellular responses help limit the damage caused by stress and thus facilitate cellular recovery. Cellular damage also triggers apoptotic cell death through several pathways. This paper briefly reviews interactions of the major heat shock proteins with ...

  4. Heat adaptation towards improve survival of Bifidobacterium longum ...

    African Journals Online (AJOL)

    This study examined the survival of Bifidobacterium longum BB 536 following the spray drying and during the storage of Medida, a fermented Sudanese cereal porridge. Medida was produced using 225 g flour of two days malted brown rice; blended in 0.405 L distilled water and cooked in 1 L boiling water. 150 g skim milk ...

  5. Heat adaptation towards improve survival of Bifidobacterium longum ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-04-20

    Apr 20, 2009 ... 150 g skim milk was added followed by sterilization; and the mixture was inoculated with B. longum. BB536 and incubated until the biomass reached approximately 9 Log CFU/ml. Spray drying inlet temperature was regulated at 160oC. The strain BB536 survivability at different outlet temperatures (95,.

  6. Heat shock genes – integrating cell survival and death

    Indian Academy of Sciences (India)

    Madhu Sudhan

    H 2004 Expression of heat-shock protein Hsp60 correlated with the apoptotic index and patient prognosis in human oesophageal squamous cell carcinoma; Eur. J. Cancer 40 2804–2811. Fink A L 1999 Chaperone-mediated protein folding; Physiol. Rev. 79 425–449. Gabai V L, Mabuchi K, Mosser D D and Sherman M Y ...

  7. Anti-Inflammatory Heat Shock Protein 70 Genes are Positively Associated with Human Survival

    DEFF Research Database (Denmark)

    Singh, Ripudaman; Kølvraa, Steen; Bross, Peter Gerd

    2010-01-01

    with longevity. The involvement of heat shock protein 70 (Hsp70) in cellular maintenance and repair mechanisms, including its role as an anti-inflammatory protein, makes it a suitable candidate for studying such associations. We have studied the association of three single nucleotide polymorphisms, HSPA1A (-110A...... the opportunity to perform survival analysis on these subjects. Haplotype relative risk, and genotype relative risk were calculated to measure the effects of haplotypes and genotypes on human survival in a sex-specific manner. A significant association of HSPA1A-AA (RR=3.864; p=0.016) and HSPA1B-AA (RR=2.764; p=0...... observations from heat shock response (HSR) study where we had shown that after heat stimulation, mononuclear cells from the carriers of genotype HSPA1L-TT had better HSR than cells with the HSPA1L-CC genotype....

  8. Molecular Genetic Analysis of Human Endometrial Mesenchymal Stem Cells That Survived Sublethal Heat Shock

    Directory of Open Access Journals (Sweden)

    A. E. Vinogradov

    2017-01-01

    Full Text Available High temperature is a critical environmental and personal factor. Although heat shock is a well-studied biological phenomenon, hyperthermia response of stem cells is poorly understood. Previously, we demonstrated that sublethal heat shock induced premature senescence in human endometrial mesenchymal stem cells (eMSC. This study aimed to investigate the fate of eMSC-survived sublethal heat shock (SHS with special emphasis on their genetic stability and possible malignant transformation using methods of classic and molecular karyotyping, next-generation sequencing, and transcriptome functional analysis. G-banding revealed random chromosome breakages and aneuploidy in the SHS-treated eMSC. Molecular karyotyping found no genomic imbalance in these cells. Gene module and protein interaction network analysis of mRNA sequencing data showed that compared to untreated cells, SHS-survived progeny revealed some difference in gene expression. However, no hallmarks of cancer were found. Our data identified downregulation of oncogenic signaling, upregulation of tumor-suppressing and prosenescence signaling, induction of mismatch, and excision DNA repair. The common feature of heated eMSC is the silence of MYC, AKT1/PKB oncogenes, and hTERT telomerase. Overall, our data indicate that despite genetic instability, SHS-survived eMSC do not undergo transformation. After long-term cultivation, these cells like their unheated counterparts enter replicative senescence and die.

  9. Effects of heat stress on survival of Frankliniella occidentalis (Thysanoptera: Thripidae) and Thrips tabaci (Thysanoptera: Thripidae).

    Science.gov (United States)

    Wang, J C; Zhang, B; Wang, J P; Li, H G; Wang, S F; Sun, L J; Zheng, C Y

    2014-08-01

    Temperature is known to play a crucial role in the population dynamics of insects. Insects have evolved different mechanisms to resist unfavorable extreme temperatures. In recent years, western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and onion thrips, Thrips tabaci (Lindeman) (Thysanoptera: Thripidae), have caused significant damage to vegetable crops. Because of global warming and expanding areas of vegetable cultivation, a study of the effects of heat stress on these thrips species is warranted. We exposed the various developmental stages of western flower thrips and onion thrips to temperatures of 41, 43, or 45 degrees C for 2, 6, 12, 24, or 36 h to determine the effects of heat stress on survival. Our results showed that the heat resistance of nonadult western flower thrips was greater than that of the nonadult onion thrips, and that the natural heat resistant ability was the primary factor in heat resistance in western flower thrips. In contrast, the heat resistance of adult onion thrips was greater than that of the adult western flower thrips, which was primarily the result of the ability of searching suitable microenvironment that enabled the onion thrips to mitigate the effects of high temperatures more efficiently than the western flower thrips. Our analysis of the differences in heat resistance between western flower thrips and onion thrips provides important information for the development of thermal treatments for controlling western flower thrips and onion thrips.

  10. Effect of heat treatment on the survival of Escherichia Coli O157:H7 ...

    African Journals Online (AJOL)

    The survival of Escherichia coli O157:H7 in raw milk treated in experimental pasteurizer was investigated in the year 2010. Raw milk was inoculated with different initial concentrations of E. coli O157:H7 and heated for 15 seconds at temperatures ranging from 69OC to 73OC. E. coli O157:H7 cells were not isolated from the ...

  11. Heat-killed Lactobacillus spp. cells enhance survivals of Caenorhabditis elegans against Salmonella and Yersinia infections.

    Science.gov (United States)

    Lee, J; Choe, J; Kim, J; Oh, S; Park, S; Kim, S; Kim, Y

    2015-12-01

    This study examined the effect of feeding heat-killed Lactobacillus cells on the survival of Caenorhabditis elegans nematodes after Salmonella Typhimurium and Yersinia enterocolitica infection. The feeding of heat-killed Lactobacillus plantarum 133 (LP133) and Lactobacillus fermentum 21 (LP21) cells to nematodes was shown to significantly increase the survival rate as well as stimulate the expression of pmk-1 gene that key factor for C. elegans immunity upon infection compared with control nematodes that were only fed Escherichia coli OP50 (OP50) cells. These results suggest that heat-killed LP133 and LF21 cells exert preventive or protective effects against the Gram-negative bacteria Salm. Typhimurium and Y. enterocolitica. To better understand the mechanisms underlying the LF21-mediated and LP133-mediated protection against bacterial infection in nematodes, transcriptional profiling was performed for each experimental group. These experiments showed that genes related to energy generation and ageing, regulators of insulin/IGF-1-like signalling, DAF genes, oxidation and reduction processes, the defence response and/or the innate immune response, and neurological processes were upregulated in nematodes that had been fed heat-killed Lactobacillus cells compared with nematodes that had been fed E. coli cells. In this study, the feeding of heat-killed Lactobacillus bacteria to Caenorhabditis elegans nematodes was shown to decrease infection by Gram-negative bacteria and increase the host lifespan. C. elegans has a small, well-organized genome and is an excellent in vivo model organism; thus, these results will potentially shed light on important Lactobacillus-host interactions. © 2015 The Society for Applied Microbiology.

  12. Survival and heat resistance of Salmonella enterica and Escherichia coli O157:H7 in peanut butter.

    Science.gov (United States)

    He, Yingshu; Guo, Dongjing; Yang, Jingyun; Tortorello, Mary Lou; Zhang, Wei

    2011-12-01

    Significant differences (P butter with different formulations and water activity. High carbohydrate content in peanut butter and low incubation temperature resulted in higher levels of bacterial survival during storage but lower levels of bacterial resistance to heat treatment.

  13. Survival and Heat Resistance of Salmonella enterica and Escherichia coli O157:H7 in Peanut Butter ▿ †

    Science.gov (United States)

    He, Yingshu; Guo, Dongjing; Yang, Jingyun; Tortorello, Mary Lou; Zhang, Wei

    2011-01-01

    Significant differences (P butter with different formulations and water activity. High carbohydrate content in peanut butter and low incubation temperature resulted in higher levels of bacterial survival during storage but lower levels of bacterial resistance to heat treatment. PMID:21965404

  14. Survival of the Fittest: Overcoming Oxidative Stress at the Extremes of Acid, Heat and Metal

    Directory of Open Access Journals (Sweden)

    Yukari Maezato

    2012-08-01

    Full Text Available The habitat of metal respiring acidothermophilic lithoautotrophs is perhaps the most oxidizing environment yet identified. Geothermal heat, sulfuric acid and transition metals contribute both individually and synergistically under aerobic conditions to create this niche. Sulfuric acid and metals originating from sulfidic ores catalyze oxidative reactions attacking microbial cell surfaces including lipids, proteins and glycosyl groups. Sulfuric acid also promotes hydrocarbon dehydration contributing to the formation of black “burnt” carbon. Oxidative reactions leading to abstraction of electrons is further impacted by heat through an increase in the proportion of reactant molecules with sufficient energy to react. Collectively these factors and particularly those related to metals must be overcome by thermoacidophilic lithoautotrophs in order for them to survive and proliferate. The necessary mechanisms to achieve this goal are largely unknown however mechanistics insights have been gained through genomic studies. This review focuses on the specific role of metals in this extreme environment with an emphasis on resistance mechanisms in Archaea.

  15. Using Loop Heat Pipes to Minimize Survival Heater Power for NASA's Evolutionary Xenon Thruster Power Processing Units

    Science.gov (United States)

    Choi, Michael K.

    2017-01-01

    A thermal design concept of using propylene loop heat pipes to minimize survival heater power for NASA's Evolutionary Xenon Thruster power processing units is presented. It reduces the survival heater power from 183 W to 35 W per power processing unit. The reduction is 81%.

  16. Toxigenic potential and heat survival of spore-forming bacteria isolated from bread and ingredients.

    Science.gov (United States)

    De Bellis, Palmira; Minervini, Fiorenza; Di Biase, Mariaelena; Valerio, Francesca; Lavermicocca, Paola; Sisto, Angelo

    2015-03-16

    Fifty-four spore-forming bacterial strains isolated from bread ingredients and bread, mainly belonging to the genus Bacillus (including Bacillus cereus), together with 11 reference strains were investigated to evaluate their cytotoxic potential and heat survival in order to ascertain if they could represent a risk for consumer health. Therefore, we performed a screening test of cytotoxic activity on HT-29 cells using bacterial culture filtrates after growing bacterial cells in Brain Heart Infusion medium and in the bread-based medium Bread Extract Broth (BEB). Moreover, immunoassays and PCR analyses, specifically targeting already known toxins and related genes of B. cereus, as well as a heat spore inactivation assay were carried out. Despite of strain variability, the results clearly demonstrated a high cytotoxic activity of B. cereus strains, even if for most of them it was significantly lower in BEB medium. Cytotoxic activity was also detected in 30% of strains belonging to species different from B. cereus, although, with a few exceptions (e.g. Bacillus simplex N58.2), it was low or very low. PCR analyses detected the presence of genes involved in the production of NHE, HBL or CytK toxins in B. cereus strains, while genes responsible for cereulide production were not detected. Production of NHE and HBL toxins was also confirmed by specific immunoassays only for B. cereus strains even if PCR analyses revealed the presence of related toxin genes also in some strains of other species. Viable spore count was ascertained after a heat treatment simulating the bread cooking process. Results indicated that B. amyloliquefaciens strains almost completely survived the heat treatment showing less than 2 log-cycle reductions similarly to two strains of B. cereus group III and single strains belonging to Bacillus subtilis, Bacillus mojavensis and Paenibacillus spp. Importantly, spores from strains of the B. cereus group IV exhibited a thermal resistance markedly lower than B

  17. Survival

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data provide information on the survival of California red-legged frogs in a unique ecosystem to better conserve this threatened species while restoring...

  18. Heat shock protein expression in relation to reproductive cycle in land snails: Implications for survival.

    Science.gov (United States)

    Mizrahi, Tal; Heller, Joseph; Goldenberg, Shoshana; Arad, Zeev

    2011-10-01

    Land snails are subject to daily and seasonal variations in temperature and in water availability and use heat shock proteins (HSPs) as part of their survival strategy. We tested whether the reproductive cycle of land snails affects the endogenous levels of HSPs, and their involvement in the reproductive process. We examined HSP levels in the foot tissue of two Sphincterochila species, S. cariosa and S. zonata, before and after laying eggs, and analyzed the albumen gland (reproductive organ) of both species and eggs of S. cariosa for the presence and quantity of various HSPs. Our study shows reduction in the expression level of Hsp70 isoforms and Hsp90 in S. zonata foot and of Hsp74 in S. cariosa foot during the period preceding egg laying compared to the post-reproductive stage. Hsp70 isoforms and Hsp25 were highly expressed in both large albumen glands and in freshly laid eggs of S. cariosa, whereas large albumen glands of S. zonata expressed mainly Hsp70 isoforms. We conclude that a trade-off between survival and fertility is responsible for the expression level of HSPs in the foot tissue of Sphincterochila snails. Our study shows that HSPs are involved in the reproductive process. We propose that parental provision of HSPs may be part of a "be prepared" strategy of Sphincterochila snails, and that HSPs may play important roles in the survival strategy of land snails during the early life stages. Our observations also highlight the importance of the reproductive status in study of whole organisms, especially when assessing the HSP response to stress. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. In utero heat stress decreases calf survival and performance through the first lactation.

    Science.gov (United States)

    Monteiro, A P A; Tao, S; Thompson, I M T; Dahl, G E

    2016-10-01

    Calves born to cows exposed to heat stress during late gestation (i.e., the dry period) have lower birth weight and weaning weight and compromised passive immune transfer compared with those born to dams that are cooled. However, it is unknown if heat stress in utero has carryover effects after weaning. The objective was to evaluate the effect of heat stress (HT) or cooling (CL) in late gestation dairy cows on the survival, growth, fertility, and milk production in the first lactation of their calves. Data of animals obtained from previous experiments conducted during 5 consecutive summers in Florida were pooled and analyzed. Cows were dried off 46d before expected calving and randomly assigned to 1 of 2 treatments, HT or CL. Cooled cows were housed with sprinklers, fans, and shade, whereas only shade was provided to HT cows. Within 4h of birth, 3.8 L of colostrum was fed to calves from both groups of cows. All calves were managed in the same manner and weaned at 49d of age. Birth weight and survival of 146 calves (HT=74; CL=72) were analyzed. Additionally, body weight, growth rate, fertility, and milk production in the first lactation from 72 heifers (HT=34; CL=38) were analyzed. As expected, HT calves were lighter (means ± SEM; 39.1±0.7 vs. 44.8±0.7kg) at birth than CL calves. Cooled heifers were heavier up to 1yr of age, but had similar total weight gain (means ± SEM; 305.8±6.3 vs. 299.1±6.3kg, respectively) compared with HT heifers. No effect of treatment was observed on age at first insemination (AI) and age at first parturition. Compared with CL heifers, HT heifers had a greater number of services per pregnancy confirmed at d 30 after AI, but no treatment effect was observed on number of services per pregnancy confirmed at d 50 after AI. A greater percentage of CL heifers reached first lactation compared with HT heifers (85.4 vs. 65.9%). Moreover, HT heifers produced less milk up to 35wk of the first lactation compared with CL heifers (means ± SEM; 26

  20. Sources and risk factors for contamination, survival, persistence, and heat resistance of Salmonella in low-moisture foods.

    Science.gov (United States)

    Podolak, Richard; Enache, Elena; Stone, Warren; Black, Darryl G; Elliott, Philip H

    2010-10-01

    Sources and risk factors for contamination, survival, persistence, and heat resistance of Salmonella in low-moisture foods are reviewed. Processed products such as peanut butter, infant formula, chocolate, cereal products, and dried milk are characteristically low-water-activity foods and do not support growth of vegetative pathogens such as Salmonella. Significant food safety risk might occur when contamination takes place after a lethal processing step. Salmonella cross-contamination in low-moisture foods has been traced to factors such as poor sanitation practices, poor equipment design, and poor ingredient control. It is well recognized that Salmonella can survive for long periods in low-moisture food products. Although some die-off occurs in low-moisture foods during storage, the degree of reduction depends on factors such as storage temperature and product formulation. The heat resistance of Salmonella is affected by many factors, mostly by strain and serotypes tested, previous growth and storage conditions, the physical and chemical food composition, test media, and the media used to recover heat-damaged cells. Salmonella heat resistance generally increases with reducing moisture. Care must be taken when applying published D- and z-values to a specific food process. The product composition and heating medium and conditions should not be significantly different from the product and process parameters used by the processors.

  1. Major E. coli heat-stress protein do not translocate: implications for cell survival.

    Science.gov (United States)

    Yatvin, M B; Clark, A W; Siegel, F L

    1987-10-01

    When Escherichia coli are exposed to heat stress, the majority of proteins in the process of synthesis at the time of heat stress are rapidly translocated to the outer membrane of the bacterium. The synthesis of most of these proteins appears to take place on membrane-bound polyribosomes. With the temperature shift, overall protein synthesis is inhibited while the synthesis of a small group of proteins is initiated. These proteins are not translocated, but remain in the cytosolic compartment, and they are identifiable as heat-stress proteins. Both the translocation phenomenon and the retention of heat-stress proteins in the cytosolic compartment in proximity to the nucleoid could counteract the effects of heat stress. The translocated proteins may operate by stabilizing the outer membrane prior to the induction of heat-stress proteins and the latter, which are confined to the cytoplasmic compartment, may serve to protect the integrity of the nucleoid structures.

  2. Impact of Sodium Chloride and Heat on Survival Time of Linguatula Serrata Nymphs in vitro: An Experimental Study

    Directory of Open Access Journals (Sweden)

    B. Hajimohammadi

    2012-07-01

    Full Text Available Introduction: Linguatula serrata is a zoonotic parasite, belonging to the class Pentastomida. The major aim of this study was to evaluate the impact of sodium chloride (NaCl and heat on survival time of Linguatula serrata nymphs. Materials & Methods: Thirty nymphs (10 in triplicate were separately transferred to plastic tubes, containing different concentrations of NaCl solution (2%, 5% and 10%. Meanwhile, 30 nymphs in tubes containing Phosphate Buffer Saline (PBS were separately treated by +50°C, +60°C and +72°C. As control group, thirty nymphs were stored in PBS at +4°C. The effects of different conditions on survival time of the nymphs were evaluated by observing their motility in different periods of time. Results: The survival time of the nymphs stored in 10% NaCl solution was too short and all of them were dead after 3 hours. But the other ones maintained in 2% NaCl solution were significantly more resistant (p<0.05 and were survived for 2 days. All the nymphs pertaining to each +60°C and +72°C treatments were found dead after first 5-minute storage interval; the nymphs stored at +50°C died totally after 20 minutes. The nymphs maintained in PBS at +4°C (control group showed the longest survival time (p<0.05; all of them were alive until day 4 and the last ones died on day 34. Conclusion: It is concluded that salting and heating have significant parasiticidal effects on L. serrata nymphs and could be used as disinfecting methods in processing of meat products especially liver. However, refrigeration at +4°C increases the resistance of the nymphs in meat products and therefore might endanger the food safety.

  3. Future heat waves due to climate change threaten the survival of Posidonia oceanica seedlings.

    Science.gov (United States)

    Guerrero-Meseguer, Laura; Marín, Arnaldo; Sanz-Lázaro, Carlos

    2017-11-01

    Extreme weather events are major drivers of ecological change, and their occurrence is likely to increase due to climate change. The transient increases in atmospheric temperatures are leading to a greater occurrence of heat waves, extreme events that can produce a substantial warming of water, especially in enclosed basins such as the Mediterranean Sea. Here, we tested the effects of current and predicted heat waves on the early stages of development of the seagrass Posidonia oceanica. Temperatures above 27 °C limited the growth of the plant by inhibiting its photosynthetic system. It suffered a reduction in leaf growth and faster leaf senescence, and in some cases mortality. This study demonstrates that the greater frequency of heat waves, along with anticipated temperature rises in coming decades, are expected to negatively affect the germination of P. oceanica seedlings. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Food matrices and cell conditions influence survival of Lactobacillus rhamnosus GG under heat stresses and during storage.

    Science.gov (United States)

    Endo, Akihito; Teräsjärvi, Johanna; Salminen, Seppo

    2014-03-17

    The present study evaluated impact of moisture content and cell conditions on survival of probiotic strain, Lactobacillus rhamnosus GG, under lethal heat stresses and during long-term storage using freeze-dried cells and oils as matrices. Viable cell counts of freeze-dried L. rhamnosus GG cells suspended in oils had only 1-log-reduction after 5min at 80°C and approximately 3-log-reduction after 20min, while no or very few viable cells were recorded for freeze dried cells suspended in buffer and cultured cells in oils. Surprisingly, freeze-dried cells suspended in oils still contained 4.3 to 6.7logCFU/ml after 5min at 95°C. Long-term storage study indicated that freeze-dried cells suspended in oils kept viable conditions for 4months, and a loss of the viability was only 0.3 to 0.6logCFU/ml. Viable cell counts of cultured cells suspended in oils were not present after 3days to 3months. These results clearly indicate that moisture and cell conditions have a great impact on survival of probiotics under severe heat stress in processing and during long-term storage. Combination of freeze-dried cells and oils as carrier provides beneficial options to preserve viability of probiotics in food processes and storage. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Survival of Campylobacter spp. in poultry meat preparations subjected to freezing, refrigeration, minor salt concentration, and heat treatment.

    Science.gov (United States)

    Sampers, Imca; Habib, Ihab; De Zutter, Lieven; Dumoulin, Ann; Uyttendaele, Mieke

    2010-02-28

    The survival of Campylobacter spp. under defined conditions of freezing (-22 degrees C) was studied in naturally contaminated chicken skin and minced chicken meat. A decline of approximately one log(10) cfu/g was observed after 1 day of freezing. No further significant reduction was achieved by prolonged storage in the freezer, although a tendency for further gradual reduction of the numbers of Campylobacter spp. present was noted. Campylobacter spp. could still be detected qualitatively (per 0.1g) after 84 days. In a second part of this study, the survival of Campylobacter spp. in a typical minced meat preparation (minced meat supplemented with 1.5% salt (NaCl)) stored at refrigeration (4 degrees C) or frozen (-22 degrees C) was studied. No significant reduction of the pathogen was observed if the minced chicken meat was kept at 4 degrees C for 14 days, opposite to approximately one log(10) cfu/g reduction after 1 day when the minced meat preparation was stored in the freezer (-22 degrees C) for 14 days. The latter reduction is imputed to the effect of freezing as mentioned above and not due to the supplementation of NaCl to minced meat or the combination of NaCl and freezing, because similar reductions of Campylobacter spp. were noticed when minced meat (without addition of NaCl) was frozen. Finally, in a third part of the study, the survival of Campylobacter spp. subjected to a heat treatment, conform to consumer-based pan-frying, in inoculated (4.5+/-0.2 cfu/g) as well as naturally contaminated chicken burgers (2.1+/-0.1 cfu/g) was studied. The Campylobacter spp. numbers declined after 2 min (internal temperature reached circa 38 degrees C), where after 4 min (internal temperature reached circa 57.5 degrees C) they dropped below detectable levels (<10 cfu/g). (c) 2009 Elsevier B.V. All rights reserved.

  6. Sterol biosynthesis is required for heat resistance but not extracellular survival in leishmania.

    Directory of Open Access Journals (Sweden)

    Wei Xu

    2014-10-01

    Full Text Available Sterol biosynthesis is a crucial pathway in eukaryotes leading to the production of cholesterol in animals and various C24-alkyl sterols (ergostane-based sterols in fungi, plants, and trypanosomatid protozoa. Sterols are important membrane components and precursors for the synthesis of powerful bioactive molecules, including steroid hormones in mammals. Their functions in pathogenic protozoa are not well characterized, which limits the development of sterol synthesis inhibitors as drugs. Here we investigated the role of sterol C14α-demethylase (C14DM in Leishmania parasites. C14DM is a cytochrome P450 enzyme and the primary target of azole drugs. In Leishmania, genetic or chemical inactivation of C14DM led to a complete loss of ergostane-based sterols and accumulation of 14-methylated sterols. Despite the drastic change in lipid composition, C14DM-null mutants (c14dm(- were surprisingly viable and replicative in culture. They did exhibit remarkable defects including increased membrane fluidity, failure to maintain detergent resistant membrane fraction, and hypersensitivity to heat stress. These c14dm(- mutants showed severely reduced virulence in mice but were highly resistant to itraconazole and amphotericin B, two drugs targeting sterol synthesis. Our findings suggest that the accumulation of toxic sterol intermediates in c14dm(- causes strong membrane perturbation and significant vulnerability to stress. The new knowledge may help improve the efficacy of current drugs against pathogenic protozoa by exploiting the fitness loss associated with drug resistance.

  7. The Urban Heat Island and its spatial scale dependent impact on survival and development in butterflies of different thermal sensitivity.

    Science.gov (United States)

    Kaiser, Aurélien; Merckx, Thomas; Van Dyck, Hans

    2016-06-01

    Climate alteration is one of the most cited ecological consequences of urbanization. However, the magnitude of this impact is likely to vary with spatial scale. We investigated how this alteration affects the biological fitness of insects, which are especially sensitive to ambient conditions and well-suited organisms to study urbanization-related changes in phenotypic traits. We monitored temperature and relative air humidity in wooded sites characterized by different levels of urbanization in the surroundings. Using a split-brood design experiment, we investigated the effect of urbanization at the local (i.e., 200 × 200 m) and landscape (i.e., 3 × 3 km) scale on two key traits of biological fitness in two closely related butterfly species that differ in thermal sensitivity. In line with the Urban Heat Island concept, urbanization led to a 1°C increase in daytime temperature and an 8% decrease in daytime relative humidity at the local scale. The thermophilous species Lasiommata megera responded at the local scale: larval survival increased twofold in urban compared to rural sites. Urbanized sites tended to produce bigger adults, although this was the case for males only. In the woodland species Pararge aegeria, which has recently expanded its ecological niche, we did not observe such a response, neither at the local, nor at the landscape scale. These results demonstrate interspecific differences in urbanization-related phenotypic plasticity and larval survival. We discuss larval pre-adaptations in species of different ecological profiles to urban conditions. Our results also highlight the significance of considering fine-grained spatial scales in urban ecology.

  8. Heat

    CERN Document Server

    Lawrence, Ellen

    2016-01-01

    Is it possible to make heat by rubbing your hands together? Why does an ice cube melt when you hold it? In this title, students will conduct experiments to help them understand what heat is. Kids will also investigate concepts such as which materials are good at conducting heat and which are the best insulators. Using everyday items that can easily be found around the house, students will transform into scientists as they carry out step-by-step experiments to answer interesting questions. Along the way, children will pick up important scientific skills. Heat includes seven experiments with detailed, age-appropriate instructions, surprising facts and background information, a "conclusions" section to pull all the concepts in the book together, and a glossary of science words. Colorful, dynamic designs and images truly put the FUN into FUN-damental Experiments.

  9. Survival rate and expression of Heat-shock protein 70 and Frost genes after temperature stress in Drosophila melanogaster lines that are selected for recovery time from temperature coma.

    Science.gov (United States)

    Udaka, Hiroko; Ueda, Chiaki; Goto, Shin G

    2010-12-01

    In this study, we investigated the physiological mechanisms underlying temperature tolerance using Drosophila melanogaster lines with rapid, intermediate, or slow recovery from heat or chill coma that were established by artificial selection or by free recombination without selection. Specifically, we focused on the relationships among their recovery from heat or chill coma, survival after severe heat or cold, and survival enhanced by rapid cold hardening (RCH) or heat hardening. The recovery time from heat coma was not related to the survival rate after severe heat. The line with rapid recovery from chill coma showed a higher survival rate after severe cold exposure, and therefore the same mechanisms are likely to underlie these phenotypes. The recovery time from chill coma and survival rate after severe cold were unrelated to RCH-enhanced survival. We also examined the expression of two genes, Heat-shock protein 70 (Hsp70) and Frost, in these lines to understand the contribution of these stress-inducible genes to intraspecific variation in recovery from temperature coma. The line showing rapid recovery from heat coma did not exhibit higher expression of Hsp70 and Frost. In addition, Hsp70 and Frost transcription levels were not correlated with the recovery time from chill coma. Thus, Hsp70 and Frost transcriptional regulation was not involved in the intraspecific variation in recovery from temperature coma. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. [Effect of heating on the survival of swine fever virus in pasteurised canned ham from experimentally infected animals (author's transl)].

    Science.gov (United States)

    Terpstra, C; Krol, B

    1976-11-15

    Experimentally infected pigs were slaughtered during viraemia. The hams were prepared according to the industrial process and packed in tins with an average content of 5.6 kg. The tins were then heated in the course of which temperatures in the centre of the hams reached maximum values varying between 62.5 and 68.5 degrees C. Within 24 hours of heating the centre of the ham was homogenised and one of two piglets were inoculated with 40 to 80 ml of a 25 per cent suspension. Virus was recovered from one out of two hams prepared at 62.5 degrees C. Virus could not be isolated from four hams processed at a maximum of 65.5 degrees C and from two hams which were heated to a maximum of 66.0 degrees and 68.5 degrees C respectively. A heart temperature of 65 degrees C for 30 minutes proved to be sufficient to eliminate all virus in the ham. The preparation of the ham and the proportionally long preheating period are considered favourable circumstances for inactivating the virus. As the hams were taken from seriously diseases animals with high viraemic titres at the time of slaughter and were injected into susceptible pigs without storage, it may be taken for granted that manufacture at the normal temperature of about 67 degrees C or above offers a sufficient margin to exclude the possible entrance of swine fever virus with contaminated ham. Virus from the virulent strains Ald, Kansas and Brescia in heparinised blood was not completely inactivated during 30 minutes at 67.2 degrees C.

  11. Survival of the faucet snail after chemical disinfection, pH extremes, and heated water bath treatments

    Science.gov (United States)

    Mitchell, A.J.; Cole, Rebecca A.

    2008-01-01

    The faucet snail Bithynia tentaculata, a nonindigenous aquatic snail from Eurasia, was introduced into Lake Michigan in 1871 and has spread to the mid-Atlantic states, the Great Lakes region, Montana, and most recently, the Mississippi River. The faucet snail serves as intermediate host for several trematodes that have caused large-scale mortality among water birds, primarily in the Great Lakes region and Montana. It is important to limit the spread of the faucet snail; small fisheries equipment can serve as a method of snail distribution. Treatments with chemical disinfection, pH extremes, and heated water baths were tested to determine their effectiveness as a disinfectant for small fisheries equipment. Two treatments eliminated all test snails: (1) a 24-h exposure to Hydrothol 191 at a concentration of at least 20 mg/L and (2) a treatment with 50°C heated water for 1 min or longer. Faucet snails were highly resistant to ethanol, NaCl, formalin, Lysol, potassium permanganate, copper sulfate, Baquacil, Virkon, household bleach, and pH extremes (as low as 1 and as high as 13).

  12. Cascading effects from survival to physiological activities, and gene expression of heat shock protein 90 on the abalone Haliotis discus hannai responding to continuous thermal stress.

    Science.gov (United States)

    Park, Kiyun; Lee, Jung Sick; Kang, Ju-Chan; Kim, Jae Won; Kwak, Ihn-Sil

    2015-02-01

    Increasing temperatures can be a significant stressor for aquatic organisms. Abalones, a type of large marine gastropods, are the most commercially important species in aquaculture for Asia. To evaluate the potential ecological risk posed by temperature stress, we measured biological responses such as survival rate, adhesion ability (falling rate), and foot abnormalities in the abalone Haliotis discus hannai. Additionally, biochemical and molecular responses were evaluated in H. discus hannai exposed to various temperature gradients. The survival rate was reduced in abalones exposed to relative high temperatures (more than 26 °C). Increased temperature stress induced a higher falling rate and abnormal foot structure. Furthermore, increased antioxidant enzyme activities were observed in abalones exposed to relative high temperatures (26 and 28 °C). The activities of superoxide dismutase were induced in a time-dependent manner after high temperature stress. Generally, heat shock protein 90 also increased significantly in H. discus hannai exposed to temperature gradients (more than 24 °C) for 12 h. These results provide valuable information regarding stress responses to increased temperatures, in H. discus hannai: adverse biological and molecular outcomes could be utilized as risk assessments and stress monitoring of marine ecosystems under increased water temperatures. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Physiochemical properties, microstructure, and probiotic survivability of nonfat goats' milk yogurt using heat-treated whey protein concentrate as fat replacer.

    Science.gov (United States)

    Zhang, Tiehua; McCarthy, James; Wang, Guorong; Liu, Yanyan; Guo, Mingruo

    2015-04-01

    There is a market demand for nonfat fermented goats' milk products. A nonfat goats' milk yogurt containing probiotics (Lactobacillus acidophilus, and Bifidobacterium spp.) was developed using heat-treated whey protein concentrate (HWPC) as a fat replacer and pectin as a thickening agent. Yogurts containing untreated whey protein concentrate (WPC) and pectin, and the one with only pectin were also prepared. Skim cows' milk yogurt with pectin was also made as a control. The yogurts were analyzed for chemical composition, water holding capacity (syneresis), microstructure, changes in pH and viscosity, mold, yeast and coliform counts, and probiotic survivability during storage at 4 °C for 10 wk. The results showed that the nonfat goats' milk yogurt made with 1.2% HWPC (WPC solution heated at 85 °C for 30 min at pH 8.5) and 0.35% pectin had significantly higher viscosity (P yogurts and lower syneresis than the goats' yogurt with only pectin (P yogurt samples did not change much throughout storage. Bifidobacterium spp. remained stable and was above 10(6) CFU g(-1) during the 10-wk storage. However, the population of Lactobacillus acidophilus dropped to below 10(6) CFU g(-1) after 2 wk of storage. Microstructure analysis of the nonfat goats' milk yogurt by scanning electron microscopy revealed that HWPC interacted with casein micelles to form a relatively compact network in the yogurt gel. The results indicated that HWPC could be used as a fat replacer for improving the consistency of nonfat goats' milk yogurt and other similar products. © 2015 Institute of Food Technologists®

  14. The effect of alginate and chitosan concentrations on some properties of chitosan-coated alginate beads and survivability of encapsulated Lactobacillus rhamnosus in simulated gastrointestinal conditions and during heat processing.

    Science.gov (United States)

    Abbaszadeh, Sepideh; Gandomi, Hassan; Misaghi, Ali; Bokaei, Saeid; Noori, Negin

    2014-08-01

    In this study, chitosan-coated alginate beads were produced with different concentrations of chitosan and alginate to evaluate the survival of encapsulated Lactobacillus rhamnosus GG during exposure to adverse conditions in gastrointestinal simulated juice and heat processing. The encapsulation yield of different encapsulation treatments was between 25 and 53.2%. Although there was a drastic decrease in pH within 48 h of incubation in MRS medium inoculated with free and encapsulated bacteria, no significant changes (P > 0.05) in bacterial count were observed among different encapsulation treatments. Moreover, the survival rate after gastrointestinal juice exposure of all prepared beads was 10-87 times greater than that of free cells and was significantly enhanced by increasing chitosan and alginate concentrations. The encapsulated bacteria survived significantly (P alginate/10 g L(-1) chitosan-encapsulated L. rhamnosus was reduced by only 2.55 log cycles. Encapsulation effectively protected L. rhamnosus against heat treatment and gastrointestinal conditions, and this effect is important in delivering sufficient numbers of viable probiotic bacteria to the gastrointestinal tract. © 2013 Society of Chemical Industry.

  15. Comparative Effect of Heat Shock on Survival of O157:H7 and Non-O157 Shiga Toxigenic Escherichia coli and Salmonella in Lean Beef with or without Moisture-Enhancing Ingredients.

    Science.gov (United States)

    Vasan, Akhila; Ingham, Steven C; Ingham, Barbara H

    2017-06-01

    Thermal tolerance of pathogenic bacteria has been shown to increase after exposure to sublethal elevated temperatures, or heat shock. We evaluated the effect of heat shock at 48°C on thermal tolerance (D 55°C ) of cocktails of O157 and non-O157 Shiga toxigenic Escherichia coli (STEC) and Salmonella in lean ground beef with or without moisture-enhancing ingredients. Beef was moisture enhanced to 110% (w) with a 5% NaCl-2.5% sodium tripolyphosphate (w/w) brine. Meat, with or without added brine, was inoculated (∼10 8 CFU/g) and heat shocked at 48°C for 0, 5, or 30 min, followed by isothermal heating at 55°C. Inoculated control samples were unenhanced and were not subject to heat shock. From the linear portion of the log CFU per gram surviving cells over time plots, D 55°C -values (minutes) were calculated. D 55°C was 20.43, 28.78, and 21.15 min for O157, non-O157, and Salmonella controls, respectively. Overall, heat shock significantly increased D 55°C , regardless of pathogen (P Salmonella, in unenhanced and enhanced samples, respectively, relative to the pathogen control. D 55°C for Salmonella was the same or significantly less than for O157 and non-O157 STEC, regardless of heat shock, and was significantly less than for O157 and non-O157 STEC in all trials with moisture-enhanced meat (P Salmonella may not prove effective against STEC in all cases and that regulators of the beef industry should focus attention on STEC in nonintact moisture-enhanced beef products.

  16. Survival of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella spp. on catfish fillets exposed to microwave heating in a continuous mode.

    Science.gov (United States)

    Sheen, Shiowshuh; Huang, Lihan; Sommers, Christopher

    2012-08-01

    Microwave (MW) heating using continuous power output with feedback control and a modified ingredient formulation may provide better and consistent cooking of foods. Currently, household units with build-in inverter power supply units are available. These new generation MW ovens provide continuous, adjustable output and cooking, in contrast to the traditional rectifier-based ovens that rely on the on-off mechanism for control. This study attempted to apply a feedback power control (termed as modified or "smart" MW oven) and phosphate treatment to further improve heating uniformity and enhance food quality and safety. Listeria monocytogenes (Lm, 4-strain cocktail), Escherichia coli O157:H7 (Ec, 5-strain cocktail), and Salmonella spp. (Sal, 6-strain cocktail), surface inoculated onto catfish fillets (75 × 100 × 15 mm; weight 110 g), were heated using the modified MW oven to study the inactivation of the pathogens. The sensitivity of these 3 bacteria to MW heating was in the order of Ec (most), Lm, and Sal (least). Greater than 4 to 5 log CFU reductions of Ec, Lm, or Sal counts on catfish fillet surfaces were inactivated within 2 min of 1250 W MW heating, where the fillet surface temperature increased from 10 to 20 °C to 80 to 90 °C. MW heating caused degradation of catfish fillet texture, which was noticeable as early as 10 to 15 s after the heating started, as evidenced by bumping sounds. Bumping can be significantly reduced by soaking fillets in phosphate solution. However, the results may need verification if applied in different MW ovens and/or with foods positioned away the geometric oven center. This study successfully demonstrated the feasibility of applying MW energy to eliminate foodborne pathogens on fish fillets. The results demonstrated in this report with the "smart" microwave oven design may enhance microwaveable food safety and quality, and therefore promote the microwaveable food business. © 2012 Institute of Food Technologists®

  17. Survival of Listeria monocytogenes, E.coli 0157:H7 and Salmonella spp. on catfish fillets exposed to microwave heating in a continuous mode

    Science.gov (United States)

    Microwave (MW) heating using continuous power output with feedback control and a modified ingredient formulation, may provide better and consistent cooking of foods. Currently, household units with build-in inverter power supply units are available. These new generation microwave ovens provide con...

  18. ClpP dependent and independent activities encoded by the polycistronic clpK-encoding locus contribute to heat shock survival in Klebsiella pneumoniae

    DEFF Research Database (Denmark)

    Bojer, Martin Saxtorph; Struve, Carsten; Ingmer, Hanne

    2013-01-01

    The family of Clp ATPases plays an important role in bacterial physiology. Here we characterize the genetic locus encompassing a newly described plasmid-encoded ClpK protein protecting Klebsiella pneumoniae cells during heat shock. We demonstrate that the clpK gene is located in a polycistronic...

  19. Effective survival of immobilized Lactobacillus casei during ripening and heat treatment of probiotic dry-fermented sausages and investigation of the microbial dynamics.

    Science.gov (United States)

    Sidira, Marianthi; Karapetsas, Athanasios; Galanis, Alex; Kanellaki, Maria; Kourkoutas, Yiannis

    2014-02-01

    The aim was the assessment of immobilized Lactobacillus casei ATCC 393 on wheat in the production of probiotic dry-fermented sausages and the investigation of the microbial dynamics. For comparison, sausages containing either free L. casei ATCC 393 or no starter culture were also prepared. During ripening, the numbers of lactobacilli exceeded 7 log cfu/g, while a drastic decrease was observed in enterobacteria, staphylococci and pseudomonas counts. Microbial diversity was further studied applying a PCR-DGGE protocol. Members of Lactobacillus, Leuconostoc, Lactococcus, Carnobacterium, Brochothrix, Bacillus and Debaryomyces were the main microbial populations detected. Microbiological and strain-specific multiplex PCR analysis confirmed that the levels of L. casei ATCC 393 in the samples after 66 days of ripening were above the minimum concentration for conferring a probiotic effect (≥ 6 log cfu/g). However, after heat treatment, this strain was detected at the above levels, only in sausages containing immobilized cells. © 2013.

  20. Checkpoint kinase 2 is dispensable for regulation of the p53 response but is required for G2/M arrest and cell survival in cells with p53 defects under heat stress.

    Science.gov (United States)

    Furusawa, Yukihiro; Yamanouchi, Yuka; Iizumi, Takashi; Zhao, Qing-Li; Mitsuhashi, Yohei; Morita, Akinori; Enomoto, Atushi; Tabuchi, Yoshiaki; Kondo, Takashi

    2017-10-01

    Hyperthermia induced by heat stress (HS) is known to inhibit proliferation and induce cell death in cancer. We previously demonstrated that checkpoint kinase 1 (Chk1) contributes to G2/M arrest and cell survival under HS; however, the role of Chk2, a functional analog of Chk1, in regulation of the cell cycle and cell death under HS is still unknown. Here, we addressed the role of Chk2 using Molt-4 cells with p53-targeted shRNA (Molt-4/shp53) and parental control cells (Molt-4/V). Chk2 inhibition suppressed C-terminal acetylation of p53 and delayed the induction of p53-target genes in Molt-4/V cells under HS; however, Chk2 inhibition failed to inhibit apoptosis induced by HS, indicating that Chk2 was dispensable for p53-dependent apoptosis under HS. In contrast, Chk2 inhibition abrogated G2/M arrest and promoted cell death induced by HS in HeLa cells and Molt-4/shp53 cells. Thus, we demonstrated for the first time that Chk2 was required for cell cycle arrest and cell survival, particularly in cells with p53 defects under HS. These findings indicated that Chk2 may be a selective target for p53-mutated or -deficient cancer treated with hyperthermia.

  1. Tid1, a cochaperone of the heat shock 70 protein and the mammalian counterpart of the Drosophila tumor suppressor l(2)tid, is critical for early embryonic development and cell survival.

    Science.gov (United States)

    Lo, Jeng-Fan; Hayashi, Masaaki; Woo-Kim, Sung; Tian, Bin; Huang, Jing-Feng; Fearns, Colleen; Takayama, Shinichi; Zapata, Juan M; Yang, Young; Lee, Jiing-Dwan

    2004-03-01

    Tid1 is the mammalian counterpart of the Drosophila tumor suppressor Tid56 and is also a DnaJ protein containing a conserved J domain through which it interacts with the heat shock protein 70 (Hsp70) family of chaperone proteins. We generated a Tid1 conditional mutation in mice, and the subsequent global removal of the Tid1 protein was achieved by crossing these conditional knockout mice with general deletor mice. No Tid1(-/-) embryos were detected as early as embryonic day 7.5 (E7.5). Nonetheless, Tid1-deficient blastocysts were viable, hatched, formed an inner cell mass and trophectoderm, and implanted (E4.5), suggesting that the homozygous mutant embryos die between E4.5 and E7.5. To assess the function of Tid1 in embryonic cells, mouse embryonic fibroblasts with the homologous Tid1 floxed allele were produced. Tid1 removal in these cells led to massive cell death. The death of Tid1-deficient cells could be rescued by ectopic expression of wild-type Tid1 but not by expression of the Tid1 protein that had a mutated J domain and was thus incapable of binding to Hsp70. We propose that Tid1 is critical for early mammalian development, most likely for its function in sustaining embryonic-cell survival, which requires its association with Hsp70.

  2. Survival Analysis

    CERN Document Server

    Miller, Rupert G

    2011-01-01

    A concise summary of the statistical methods used in the analysis of survival data with censoring. Emphasizes recently developed nonparametric techniques. Outlines methods in detail and illustrates them with actual data. Discusses the theory behind each method. Includes numerous worked problems and numerical exercises.

  3. Modelling survival

    DEFF Research Database (Denmark)

    Ashauer, Roman; Albert, Carlo; Augustine, Starrlight

    2016-01-01

    well GUTS, calibrated with short-term survival data of Gammarus pulex exposed to four pesticides, can forecast effects of longer-term pulsed exposures. Thirdly, we tested the ability of GUTS to estimate 14-day median effect concentrations of malathion for a range of species and use these estimates...

  4. Heat Islands

    Science.gov (United States)

    EPA's Heat Island Effect Site provides information on heat islands, their impacts, mitigation strategies, related research, a directory of heat island reduction initiatives in U.S. communities, and EPA's Heat Island Reduction Program.

  5. Heat Waves

    Science.gov (United States)

    Heat Waves Dangers we face during periods of very high temperatures include: Heat cramps: These are muscular pains and ... having trouble with the heat. If a heat wave is predicted or happening… - Slow down. Avoid strenuous ...

  6. Innovations’ Survival

    Directory of Open Access Journals (Sweden)

    Jakub Tabas

    2016-01-01

    Full Text Available Innovations currently represent a tool of maintaining the going concern of a business entity and its competitiveness. However, effects of innovations are not infinite and if an innovation should constantly preserve a life of business entity, it has to be a continual chain of innovations, i.e. continual process. Effective live of a single innovation is limited while the limitation is derived especially from industry. The paper provides the results of research on innovations effects in the financial performance of small and medium-sized enterprises in the Czech Republic. Objective of this paper is to determine the length and intensity of the effects of technical innovations in company’s financial performance. The economic effect of innovations has been measured at application of company’s gross production power while the Deviation Analysis has been applied for three years’ time series. Subsequently the Survival Analysis has been applied. The analyses are elaborated for three statistical samples of SMEs constructed in accordance to the industry. The results obtained show significant differences in innovations’ survival within these three samples of enterprises then. The results are quite specific for the industries, and are confronted and discussed with the results of authors’ former research on the issue.

  7. Heat Stress

    Science.gov (United States)

    ... Publications and Products Programs Contact NIOSH NIOSH HEAT STRESS Recommend on Facebook Tweet Share Compartir NEW OSHA- ... hot environments may be at risk of heat stress. Exposure to extreme heat can result in occupational ...

  8. Heat pumps

    CERN Document Server

    Macmichael, DBA

    1988-01-01

    A fully revised and extended account of the design, manufacture and use of heat pumps in both industrial and domestic applications. Topics covered include a detailed description of the various heat pump cycles, the components of a heat pump system - drive, compressor, heat exchangers etc., and the more practical considerations to be taken into account in their selection.

  9. Heat pumps

    CERN Document Server

    Brodowicz, Kazimierz; Wyszynski, M L; Wyszynski

    2013-01-01

    Heat pumps and related technology are in widespread use in industrial processes and installations. This book presents a unified, comprehensive and systematic treatment of the design and operation of both compression and sorption heat pumps. Heat pump thermodynamics, the choice of working fluid and the characteristics of low temperature heat sources and their application to heat pumps are covered in detail.Economic aspects are discussed and the extensive use of the exergy concept in evaluating performance of heat pumps is a unique feature of the book. The thermodynamic and chemical properties o

  10. HEAT RECUPERATION

    Directory of Open Access Journals (Sweden)

    S. L. Rovin

    2011-01-01

    Full Text Available Heat recovery is an effective method of shortening specific energy consumption. new constructions of recuperators for heating and cupola furnaces have been designed and successfully introduced. two-stage recuperator with computer control providing blast heating up to 600 °C and reducing fuel consumption by 30% is of special interest.

  11. Heated Goggles

    Science.gov (United States)

    1978-01-01

    The electrically heated ski goggles shown incorporate technology similar to that once used in Apollo astronauts' helmet visors, and for the same reason-providing fogfree sight in an activity that demands total vision. Defogging is accomplished by applying heat to prevent moisture condensation. Electric heat is supplied by a small battery built into the h goggles' headband. Heat is spread across the lenses by means of an invisible coating of electrically conductive metallic film. The goggles were introduced to the market last fall. They were designed by Sierracin Corporation, Sylmar, California, specialists in the field of heated transparent materials. The company produces heated windshields for military planes and for such civil aircraft as the Boeing 747, McDonnell Douglas DC-10 and Lockheed L-1011 TriStar.

  12. Survival strategies in arctic ungulates

    Directory of Open Access Journals (Sweden)

    N. J. C. Tyler

    1990-09-01

    Full Text Available Arctic ungulates usually neither freeze nor starve to death despite the rigours of winter. Physiological adaptations enable them to survive and reproduce despite long periods of intense cold and potential undernutrition. Heat conservation is achieved by excellent insulation combined with nasal heat exchange. Seasonal variation in fasting metabolic rate has been reported in several temperate and sub-arctic species of ungulates and seems to occur in muskoxen. Surprisingly, there is no evidence for this in reindeer. Both reindeer and caribou normally maintain low levels of locomotor activity in winter. Light foot loads are important for reducing energy expenditure while walking over snow. The significance and control of selective cooling of the brain during hard exercise (e.g. escape from predators is discussed. Like other cervids, reindeer and caribou display a pronounced seasonal cycle of appetite and growth which seems to have an intrinsic basis. This has two consequences. First, the animals evidently survive perfectly well despite enduring negative energy balance for long periods. Second, loss of weight in winter is not necessarily evidence of undernutrition. The main role of fat reserves, especially in males, may be to enhance reproductive success. The principal role of fat reserves in winter appears to be to provide a supplement to, rather than a substitute for, poor quality winter forage. Fat also provides an insurance against death during periods of acute starvation.

  13. Heat Stroke

    DEFF Research Database (Denmark)

    Mørch, Sofie Søndergaard; Andersen, Johnny Dohn Holmgren; Bestle, Morten Heiberg

    2017-01-01

    Heat stroke is an acute, life-threatening emergency characterized clinically by elevated body temperature and central nervous system dysfunction. Early recognition and treatment including aggressive cooling and management of life-threatening systemic complications are essential to reduce morbidity...... and mortality. This case report describes two Danish patients diagnosed with heat stroke syndrome during a heat wave in the summer of 2014. Both patients were morbidly obese and had several predisposing illnesses. However since heat stroke is a rare condition in areas with temperate climate, they were...... not diagnosed until several days after admittance; hence treatment with cooling was delayed. Both patients were admitted to the intensive care unit, where they were treated with an external cooling device and received treatment for complications. Both cases ended fatally. As global warming continues, more heat...

  14. Heat pipes

    CERN Document Server

    Dunn, Peter D

    1994-01-01

    It is approximately 10 years since the Third Edition of Heat Pipes was published and the text is now established as the standard work on the subject. This new edition has been extensively updated, with revisions to most chapters. The introduction of new working fluids and extended life test data have been taken into account in chapter 3. A number of new types of heat pipes have become popular, and others have proved less effective. This is reflected in the contents of chapter 5. Heat pipes are employed in a wide range of applications, including electronics cooling, diecasting and injection mo

  15. Heat transfer and vascular cambium necrosis in the boles of trees during surface fires

    Science.gov (United States)

    M. B. Dickinson

    2002-01-01

    Heat-transfer and cell-survival models are used to link surface fire behavior with vascular cambium necrosis from heating by flames. Vascular cambium cell survival was predicted with a numerical model based on the kinetics of protein denaturation and parameterized with data from the literature. Cell survival was predicted for vascular cambium temperature regimes...

  16. Multinationals and plant survival

    DEFF Research Database (Denmark)

    Bandick, Roger

    2010-01-01

    The aim of this paper is twofold: first, to investigate how different ownership structures affect plant survival, and second, to analyze how the presence of foreign multinational enterprises (MNEs) affects domestic plants’ survival. Using a unique and detailed data set on the Swedish manufacturing...... sector, I am able to separate plants into those owned by foreign MNEs, domestic MNEs, exporting non-MNEs, and purely domestic firms. In line with previous findings, the result, when conditioned on other factors affecting survival, shows that foreign MNE plants have lower survival rates than non......-MNE plants. However, separating the non-MNEs into exporters and non-exporters, the result shows that foreign MNE plants have higher survival rates than non-exporting non-MNEs, while the survival rates of foreign MNE plants and exporting non-MNE plants do not seem to differ. Moreover, the simple non...

  17. Modular Heat Exchanger With Integral Heat Pipe

    Science.gov (United States)

    Schreiber, Jeffrey G.

    1992-01-01

    Modular heat exchanger with integral heat pipe transports heat from source to Stirling engine. Alternative to heat exchangers depending on integrities of thousands of brazed joints, contains only 40 brazed tubes.

  18. Heat convection

    Energy Technology Data Exchange (ETDEWEB)

    Jiji, L.M. [City Univ. of New York, NY (United States). Dept. of Mechanical Engineering

    2006-07-01

    Professor Jiji's broad teaching experience lead him to select the topics for this book to provide a firm foundation for convection heat transfer with emphasis on fundamentals, physical phenomena, and mathematical modelling of a wide range of engineering applications. Reflecting recent developments, this textbook is the first to include an introduction to the challenging topic of microchannels. The strong pedagogic potential of Heat Convection is enhanced by the following ancillary materials: (1) Power Point lectures, (2) Problem Solutions, (3) Homework Facilitator, and, (4) Summary of Sections and Chapters. (orig.)

  19. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... for signs of heat stroke or exhaustion. Heat Stroke and Exhaustion Symptoms of early heat exhaustion symptoms ... heavy sweating; nausea; and giddiness. Symptoms of heat stroke (late stage of heat illness) include flushed, hot, ...

  20. Renewable Heating and Cooling

    Science.gov (United States)

    Renewable heating and cooling is a set of alternative resources and technologies that can be used in place of conventional heating and cooling technologies for common applications such as water heating, space heating, space cooling and process heat.

  1. Infrared heating

    Science.gov (United States)

    IR heating was first industrially used in the 1930s for automotive curing applications and rapidly became a widely applied technology in the manufacturing industry. Contrarily, a slower pace in the development of IR technologies for processing foods and agricultural products was observed, due to lim...

  2. Modular heat pipe radiators for enhanced Shuttle mission capabilities

    Science.gov (United States)

    Alario, J.; Haslett, R.

    1979-01-01

    Current heat pipe radiator technology is reviewed and the results from three state-of-the-art hardware programs are summarized. Heat pipe radiators are shown to be an improvement over all-fluid loop panels for long duration space missions, when micrometeoroid survivability is important. Finally, several heat pipe radiator design concepts are presented which would enhance Shuttle mission capabilities by either extending mission life and/or augmenting heat rejection capability.

  3. Network ties and survival

    DEFF Research Database (Denmark)

    Acheampong, George; Narteh, Bedman; Rand, John

    2017-01-01

    Poultry farming has been touted as one of the major ways by which poverty can be reduced in low-income economies like Ghana. Yet, anecdotally there is a high failure rate among these poultry farms. This current study seeks to understand the relationship between network ties and survival chances...... of small commercial poultry farms (SCPFs). We utilize data from a 2-year network survey of SCPFs in rural Ghana. The survival of these poultry farms are modelled using a lagged probit model of farms that persisted from 2014 into 2015. We find that network ties are important to the survival chances...... but this probability reduces as the number of industry ties increases but moderation with dynamic capability of the firm reverses this trend. Our findings show that not all network ties aid survival and therefore small commercial poultry farmers need to be circumspect in the network ties they cultivate and develop....

  4. Heat pump

    OpenAIRE

    Klíma, Martin

    2010-01-01

    Bakalářská práce popisuje a charakterizuje tepelné čerpadlo. Obsahuje souhrn jednotlivých druhů tepelných čerpadel z hlediska získávání energie, princip jejich funkce a popis odlišností mezi jednotlivými druhy kompresorů, použití pracovní látky a její vývin do budoucna. Závěrem je zde uveden můj vlastní názor na tepelné čerpadlo, které bych preferoval. Bachelor thesis describes and characterizes the heat pump. Summarizes the various types of heat pumps in terms of energy production, princi...

  5. Heat Exchange

    OpenAIRE

    Bottomley, Stephen

    2012-01-01

    Heat Exchange’ is an international touring exhibition of enamel metalwork curated by Turrell.E (UK), Gegenwart (Germany/UK) and Cameron (Australia). Bottomley was one of twenty-three international artists invited to join a transcontinental on-line blog and forum that recorded individual contemporary approaches to working with vitreous enamel the year prior to the 2012 exhibition that coincided with the SNAG (Society of North American Goldsmiths) National Conference in Phoenix Arizona USA.Vitr...

  6. Aircraft Survivability: Rotorcraft Survivability. Summer 2010

    Science.gov (United States)

    2010-01-01

    protect those who serve to protect us?” The answer is a mixed bag. I am fortunate to have joined a group of dedicated men and women who represent this...and Service subject matter experts on rotorcraft safety and survivability to complete the study and report the results to the Joint Chiefs of...Operations and Support CDD TEMP DT DT/OT LUT IOT &E BLRIP TEMP TEMP LRIP Acquisition & LFT Strategies B C LFT&E Review Requirements Approve TEMPs

  7. Heat pump system

    Science.gov (United States)

    Swenson, Paul F.; Moore, Paul B.

    1979-01-01

    An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchangers and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

  8. Survival tactics within thermally-challenging roosts: heat tolerance ...

    African Journals Online (AJOL)

    We studied roost microclimates, thermal preferences and temperature-related variation in body tem- peratures and flight abilities of M. condylurus from three roosts in man-made structures in South. Africa. Roosts were characterized by marked spatio-temporal variability in ambient temperature and relative humidity on a ...

  9. Survival tactics within thermally-challenging roosts: heat tolerance ...

    African Journals Online (AJOL)

    ured ambient dry bulb temperature, relative humidity, solar radiation levels and windspeed. Data were ... their location(s) in the roost was determined in- directly using a stethoscope placed against the wooden panel- ling. .... ing the peak of the day (10:00-14:00), external solar radiation levels were highly variable owing to ...

  10. Heat-Exchanger/Heat-Pipe Interface

    Science.gov (United States)

    Snyder, H. J.; Van Hagan, T. H.

    1987-01-01

    Monolithic assembly reliable and light in weight. Heat exchanger and evaporator ends of heat pipes integrated in monolithic halves welded together. Interface assembly connects heat exchanger of furnace, reactor, or other power source with heat pipes carrying heat to radiator or power-consuming system. One of several concepts proposed for nuclear power supplies aboard spacecraft, interface useful on Earth in solar thermal power systems, heat engines, and lightweight cooling systems.

  11. Heating systems for heating subsurface formations

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Scott Vinh [Houston, TX; Vinegar, Harold J [Bellaire, TX

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  12. Hydride heat pump with heat regenerator

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative hydride heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system. A series of at least four canisters containing a lower temperature performing hydride and a series of at least four canisters containing a higher temperature performing hydride is provided. Each canister contains a heat conductive passageway through which a heat transfer fluid is circulated so that sensible heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  13. Overcoming heat shock protein inhibition at critical temperature vital ...

    African Journals Online (AJOL)

    Overcoming heat shock protein inhibition at critical temperature vital for survival in Solanum tuberosum L. in vivo condition. Bengyella Louis, Pranab Roy, Tamgue Ousman, Sayanika Waikhom Devi, Narayan Chandra Talukdar ...

  14. Heat pipes

    CERN Document Server

    Dunn, Peter D

    1982-01-01

    A comprehensive, up-to-date coverage of the theory, design and manufacture of heat pipes and their applications. This latest edition has been thoroughly revised, up-dated and expanded to give an in-depth coverage of the new developments in the field. Significant new material has been added to all the chapters and the applications section has been totally rewritten to ensure that topical and important applications are appropriately emphasised. The bibliography has been considerably enlarged to incorporate much valuable new information. Thus readers of the previous edition, which has established

  15. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Emergencies A-Z Share this! Home » Emergency 101 Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at ... about heat cramps and heat stroke and exhaustion. Heat Cramps Symptoms include muscle spasms, usually in the ...

  16. Low temperature nuclear heat

    Energy Technology Data Exchange (ETDEWEB)

    Kotakorpi, J.; Tarjanne, R. (comps.)

    1977-08-01

    The meeting was concerned with the use of low grade nuclear heat for district heating, desalination, process heat, and agriculture and aquaculture. The sessions covered applications and demand, heat sources, and economics.

  17. Regenerative Hydride Heat Pump

    Science.gov (United States)

    Jones, Jack A.

    1992-01-01

    Hydride heat pump features regenerative heating and single circulation loop. Counterflow heat exchangers accommodate different temperatures of FeTi and LaNi4.7Al0.3 subloops. Heating scheme increases efficiency.

  18. Proof-Carrying Survivability

    Science.gov (United States)

    2013-01-15

    pp.289-302 ( Impact factor : 2.09). 2. Julic, J. and Zuo, Y. (2012). “An RFID Survivability Impact Model in the Military Domain”, Proc. of 18 th...Availability, Reliability and Security, 40(4), pp. 406-418 ( Impact factor : 2.016). 10. Zuo, Y. (2010). “A Holistic Approach for Specification of Security... Impact factor : 1.596). 20. Zuo, Y., Pimple, M. and Lande, S. (2009). “A Framework for RFID Survivability Requirement Analysis and Specification”, Proc

  19. Segmented heat exchanger

    Science.gov (United States)

    Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

    2010-12-14

    A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

  20. Dual source heat pump

    Science.gov (United States)

    Ecker, Amir L.; Pietsch, Joseph A.

    1982-01-01

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

  1. ICRF heating on helical devices

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, D.A.; Lyon, J.F.; Hoffman, D.J.; Murakami, M.; England, A.C.; Wilgen, J.B.; Jaeger, E.F.; Wang, C.; Batchelor, D.B.

    1995-09-01

    Ion cyclotron range of frequency (ICRF) heating is currently in use on CHS and W7-AS and is a major element of the heating planned for steady state helical devices. In helical devices, the lack of a toroidal current eliminates both disruptions and the need for ICRF current drive, simplifying the design of antenna structures as compared to tokamak applications. However the survivability of plasma facing components and steady state cooling issues are directly applicable to tokamak devices. Results from LHD steady state experiments should be available on a time scale to strongly influence the next generation of steady state tokamak experiments. The helical plasma geometry provides challenges not faced with tokamak ICRF heating, including the potential for enhanced fast ion losses, impurity accumulation, limited access for antenna structures, and open magnetic field lines in the plasma edge. The present results and near term plans provide the basis for steady state ICRF heating of larger helical devices. An approach which includes direct electron, mode conversion, ion minority and ion Bernstein wave heating addresses these issues.

  2. ICRF heating on helical devices

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, D.A.; Lyon, J.F.; Hoffman, D.J. [and others

    1995-09-01

    Ion cyclotron range of frequency (ICRF) heating is currently in use on CHS and W7AS and is a major element of the heating planned for steady state helical devices. In helical devices, the lack of a toroidal current eliminates both disruptions and the need for ICRF current drive, simplifying the design of antenna structures as compared to tokamak applications. However the survivability of plasma facing components and steady state cooling issues are directly applicable to tokamak devices. Results from LHD steady state experiments should be available on a time scale to strongly influence the next generation of steady state tokamak experiments. The helical plasma geometry provides challenges not faced with tokamak ICRF heating, including the potential for enhanced fast ion losses, impurity accumulation, limited access for antenna structures, and open magnetic field lines in the plasma edge. The present results and near term plans provide the basis for steady state ICRF heating of larger helical devices. An approach which includes direct electron, mode conversion, ion minority and ion Bernstein wave heating addresses these issues.

  3. Survivability via Control Objectives

    Energy Technology Data Exchange (ETDEWEB)

    CAMPBELL,PHILIP L.

    2000-08-11

    Control objectives open an additional front in the survivability battle. A given set of control objectives is valuable if it represents good practices, it is complete (it covers all the necessary areas), and it is auditable. CobiT and BS 7799 are two examples of control objective sets.

  4. Artists’ Survival Rate

    DEFF Research Database (Denmark)

    Bille, Trine; Jensen, Søren

    2017-01-01

    The literature of cultural economics generally finds that an artistic education has no significant impact on artists’ income and careers in the arts. In our research, we have readdressed this question by looking at the artists’ survival in the arts occupations. The results show that an artistic...... education has a significant impact on artists’ careers in the arts and we find important industry differences....

  5. Education for Survival

    Science.gov (United States)

    Aldrich, Richard

    2010-01-01

    This article provides a brief overview of current approaches to education and concludes that none of these is sufficient to meet the challenges that now face the human race. It argues instead for a new concept of education for survival. (Contains 1 note.)

  6. Flexible survival regression modelling

    DEFF Research Database (Denmark)

    Cortese, Giuliana; Scheike, Thomas H; Martinussen, Torben

    2009-01-01

    Regression analysis of survival data, and more generally event history data, is typically based on Cox's regression model. We here review some recent methodology, focusing on the limitations of Cox's regression model. The key limitation is that the model is not well suited to represent time-varyi...

  7. Seeds to survive

    NARCIS (Netherlands)

    Groot, S.P.C.

    2002-01-01

    Seeds are important for man, either as propagation material of crops or directly for the production of foods, fodder and drinks. The natural function of seeds is dispersal of its genes to successive generations. Survival mechanisms seed have evolved sometimes interfere with those preferred by

  8. Survival After Retirement.

    Science.gov (United States)

    Holloway, Clark; Youngblood, Stuart A.

    1986-01-01

    Examined survival rates after retirement in a large corporation. A regression analysis was performed to control for age, sex, job status, and type of work differences that may influence longevity. Short-term suvivors seemed to undergo a different adjustment process than long-term survivors. (Author/ABL)

  9. Heat shock protein 90: the cancer chaperone

    Indian Academy of Sciences (India)

    2007-04-02

    Apr 2, 2007 ... Heat shock protein 90 (Hsp90) is a molecular chaperone required for the stability and function of a number of conditionally activated and/or expressed signalling proteins, as well as multiple mutated, chimeric, and/or over-expressed signalling proteins, that promote cancer cell growth and/or survival. Hsp90 ...

  10. Nonazeotropic Heat Pump

    Science.gov (United States)

    Ealker, David H.; Deming, Glenn

    1991-01-01

    Heat pump collects heat from water circulating in heat-rejection loop, raises temperature of collected heat, and transfers collected heat to water in separate pipe. Includes sealed motor/compressor with cooling coils, evaporator, and condenser, all mounted in outer housing. Gradients of temperature in evaporator and condenser increase heat-transfer efficiency of vapor-compression cycle. Intended to recover relatively-low-temperature waste heat and use it to make hot water.

  11. Heat stress reduction of helicopter crew wearing a ventilated vest

    NARCIS (Netherlands)

    Reffeltrath, P.A.

    2006-01-01

    Background: Helicopter pilots are often exposed to periods of high heat strain, especially when wearing survival suits. Therefore, a prototype of a ventilated vest was evaluated on its capability to reduce the heat strain of helicopter pilots during a 2-h simulated flight. Hypothesis: It was

  12. Overcoming heat shock protein inhibition at critical temperature vital ...

    African Journals Online (AJOL)

    Bengyella

    2012-06-12

    Jun 12, 2012 ... Conclusion. The ability to rapidly escape heat mediated HSPs inhibition at the onset of severe heat-stress is crucial for survival in potato. This potential can serve as a selection criterion for breeding primal varieties and generating thermo tolerant genotypes adaptable to the estimated mean global warming ...

  13. Effects of pasteurisation on survival patterns of microorganisms and ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-01

    Dec 1, 2009 ... only Bacillus Subtilis and Saccharomyces cerevisiae as the surviving organisms. The D70 -value of the most heat resistant organism B. subtilis was found to be 6.5 .... from the water-bathed medium and immediately cooled by immersion in cold water to attain room temperature. Determination of vitamin C.

  14. High heat flux single phase heat exchanger

    Science.gov (United States)

    Valenzuela, Javier A.; Izenson, Michael G.

    1990-01-01

    This paper presents the results obtained to date in a program to develop a high heat flux, single-phase heat exchanger for spacecraft thermal management. The intended application is a net generation interface heat exchanger to couple the crew module water thermal bus to the two-phase ammonia main thermal bus in the Space Station Freedom. The large size of the interface heat exchanger is dictated by the relatively poor water-side heat transfer characteristics. The objective of this program is to develop a single-phase heat transfer approach which can achieve heat fluxes and heat transfer coefficients comparable to those of the evaporation ammonia side. A new heat exchanger concept has been developed to meet these objecties. The main feature of this heat exchanger is that it can achieve very high heat fluxes with a pressure drop one to two orders of magnitude lower than those of previous microchannel or jet impingement high heat flux heat exchangers. This paper describes proof-of-concept experiments performed in air and water and presents analytical model of the heat exchanger.

  15. Surviving Sepsis Campaign

    DEFF Research Database (Denmark)

    Rhodes, Andrew; Evans, Laura E; Alhazzani, Waleed

    2017-01-01

    OBJECTIVE: To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012". DESIGN: A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings......, and to formulate recommendations as strong or weak, or best practice statement when applicable. RESULTS: The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations...... of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality....

  16. Surviving Sepsis Campaign

    DEFF Research Database (Denmark)

    Rhodes, Andrew; Evans, Laura E; Alhazzani, Waleed

    2017-01-01

    OBJECTIVE: To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012." DESIGN: A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings......, and to formulate recommendations as strong or weak, or best practice statement when applicable. RESULTS: The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations...... of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality....

  17. Multiple source heat pump

    Science.gov (United States)

    Ecker, Amir L.

    1983-01-01

    A heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating a fluid in heat exchange relationship with a refrigerant fluid, at least three refrigerant heat exchangers, one for effecting heat exchange with the fluid, a second for effecting heat exchange with a heat exchange fluid, and a third for effecting heat exchange with ambient air; a compressor for compressing the refrigerant; at least one throttling valve connected at the inlet side of a heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circuit and pump for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and directional flow of refrigerant therethrough for selecting a particular mode of operation. Also disclosed are a variety of embodiments, modes of operation, and schematics therefor.

  18. Cryogenic heat transfer

    CERN Document Server

    Barron, Randall F

    2016-01-01

    Cryogenic Heat Transfer, Second Edition continues to address specific heat transfer problems that occur in the cryogenic temperature range where there are distinct differences from conventional heat transfer problems. This updated version examines the use of computer-aided design in cryogenic engineering and emphasizes commonly used computer programs to address modern cryogenic heat transfer problems. It introduces additional topics in cryogenic heat transfer that include latent heat expressions; lumped-capacity transient heat transfer; thermal stresses; Laplace transform solutions; oscillating flow heat transfer, and computer-aided heat exchanger design. It also includes new examples and homework problems throughout the book, and provides ample references for further study.

  19. Heat pump technology

    CERN Document Server

    Von Cube, Hans Ludwig; Goodall, E G A

    2013-01-01

    Heat Pump Technology discusses the history, underlying concepts, usage, and advancements in the use of heat pumps. The book covers topics such as the applications and types of heat pumps; thermodynamic principles involved in heat pumps such as internal energy, enthalpy, and exergy; and natural heat sources and energy storage. Also discussed are topics such as the importance of the heat pump in the energy industry; heat pump designs and systems; the development of heat pumps over time; and examples of practical everyday uses of heat pumps. The text is recommended for those who would like to kno

  20. Cracking the survival code

    Science.gov (United States)

    Füllgrabe, Jens; Heldring, Nina; Hermanson, Ola; Joseph, Bertrand

    2014-01-01

    Modifications of histones, the chief protein components of the chromatin, have emerged as critical regulators of life and death. While the “apoptotic histone code” came to light a few years ago, accumulating evidence indicates that autophagy, a cell survival pathway, is also heavily regulated by histone-modifying proteins. In this review we describe the emerging “autophagic histone code” and the role of histone modifications in the cellular life vs. death decision. PMID:24429873

  1. Artillery Survivability Model

    Science.gov (United States)

    2016-06-01

    experiment mode also enables users to set their own design of experiment by manipulating an editable CSV file. The second one is a real-time mode that...renders a 3D virtual environment of a restricted battlefield where the survivability movements of an artillery company are visualized . This mode...provides detailed visualization of the simulation and enables future experimental uses of the simulation as a training tool. 14. SUBJECT TERMS

  2. Survival analysis models and applications

    CERN Document Server

    Liu, Xian

    2012-01-01

    Survival analysis concerns sequential occurrences of events governed by probabilistic laws.  Recent decades have witnessed many applications of survival analysis in various disciplines. This book introduces both classic survival models and theories along with newly developed techniques. Readers will learn how to perform analysis of survival data by following numerous empirical illustrations in SAS. Survival Analysis: Models and Applications: Presents basic techniques before leading onto some of the most advanced topics in survival analysis.Assumes only a minimal knowledge of SAS whilst enablin

  3. Oscillating heat pipes

    CERN Document Server

    Ma, Hongbin

    2015-01-01

    This book presents the fundamental fluid flow and heat transfer principles occurring in oscillating heat pipes and also provides updated developments and recent innovations in research and applications of heat pipes. Starting with fundamental presentation of heat pipes, the focus is on oscillating motions and its heat transfer enhancement in a two-phase heat transfer system. The book covers thermodynamic analysis, interfacial phenomenon, thin film evaporation,  theoretical models of oscillating motion and heat transfer of single phase and two-phase flows, primary  factors affecting oscillating motions and heat transfer,  neutron imaging study of oscillating motions in an oscillating heat pipes, and nanofluid’s effect on the heat transfer performance in oscillating heat pipes.  The importance of thermally-excited oscillating motion combined with phase change heat transfer to a wide variety of applications is emphasized. This book is an essential resource and learning tool for senior undergraduate, gradua...

  4. Heat Related Illnesses

    National Research Council Canada - National Science Library

    Carter, R; Cheuvront, S. N; Sawka, M. N

    2006-01-01

    .... The risk of serious heat illness can be markedly reduced by implementing a variety of countermeasures, including becoming acclimated to the heat, managing heat stress exposure, and maintaining hydration...

  5. Heat Roadmap Europe 1

    DEFF Research Database (Denmark)

    Connolly, David; Mathiesen, Brian Vad; Østergaard, Poul Alberg

    2012-01-01

    Heat Roadmap Europe (Pre-study 1) investigates the role of district heating in the EU27 energy system by mapping local conditions across Europe, identifying the potential for district heating expansion, and subsequently simulating the potential resource in an hourly model of the EU27 energy system....... In 2010, approximately 12% of the space heating demand in Europe is met by district heating, but in this study four alternative scenarios are considered for the EU27 energy system: 1. 2010 with 30% district heating 2. 2010 with 50% district heating 3. 2030 with 30% district heating 4. 2050 with 50......% district heating These scenarios are investigated in two steps. Firstly, district heating replaces individual boilers by converting condensing power plants to combined heat and power plants (CHP) to illustrate how district heating improves the overall efficiency of the energy system. In the second step...

  6. Multidimensional Heat Conduction

    DEFF Research Database (Denmark)

    Rode, Carsten

    1998-01-01

    Analytical theory of multidimensional heat conduction. General heat conduction equation in three dimensions. Steay state, analytical solutions. The Laplace equation. Method of separation of variables. Principle of superposition. Shape factors. Transient, multidimensional heat conduction....

  7. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... sweating; nausea; and giddiness. Symptoms of heat stroke (late stage of heat illness) include flushed, hot, dry ... consciousness, vomiting or a high body temperature. For late stage heat stroke symptoms, cool the person further ...

  8. Absorption heat pump system

    Science.gov (United States)

    Grossman, Gershon

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  9. Applied survival analysis using R

    CERN Document Server

    Moore, Dirk F

    2016-01-01

    Applied Survival Analysis Using R covers the main principles of survival analysis, gives examples of how it is applied, and teaches how to put those principles to use to analyze data using R as a vehicle. Survival data, where the primary outcome is time to a specific event, arise in many areas of biomedical research, including clinical trials, epidemiological studies, and studies of animals. Many survival methods are extensions of techniques used in linear regression and categorical data, while other aspects of this field are unique to survival data. This text employs numerous actual examples to illustrate survival curve estimation, comparison of survivals of different groups, proper accounting for censoring and truncation, model variable selection, and residual analysis. Because explaining survival analysis requires more advanced mathematics than many other statistical topics, this book is organized with basic concepts and most frequently used procedures covered in earlier chapters, with more advanced topics...

  10. Regenerative adsorbent heat pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  11. Survival after blood transfusion

    DEFF Research Database (Denmark)

    Kamper-Jørgensen, Mads; Ahlgren, Martin; Rostgaard, Klaus

    2008-01-01

    of transfusion recipients in Denmark and Sweden followed for up to 20 years after their first blood transfusion. Main outcome measure was all-cause mortality. RESULTS: A total of 1,118,261 transfusion recipients were identified, of whom 62.0 percent were aged 65 years or older at the time of their first...... the SMR remained significantly 1.3-fold increased. CONCLUSION: The survival and relative mortality patterns among blood transfusion recipients were characterized with unprecedented detail and precision. Our results are relevant to assessments of the consequences of possible transfusion-transmitted disease...... as well as for cost-benefit estimation of new blood safety interventions....

  12. Nuclear War Survival Skills

    Energy Technology Data Exchange (ETDEWEB)

    Kearny, C.H.

    2002-06-24

    The purpose of this book is to provide Americans with information and instructions that will significantly increase their chances of surviving a possible nuclear attack. It brings together field-tested instructions that, if followed by a large fraction of Americans during a crisis that preceded an attack, could save millions of lives. The author is convinced that the vulnerability of our country to nuclear threat or attack must be reduced and that the wide dissemination of the information contained in this book would help achieve that objective of our overall defense strategy.

  13. Design of survivable networks

    CERN Document Server

    Stoer, Mechthild

    1992-01-01

    The problem of designing a cost-efficient network that survives the failure of one or more nodes or edges of the network is critical to modern telecommunications engineering. The method developed in this book is designed to solve such problems to optimality. In particular, a cutting plane approach is described, based on polyhedral combinatorics, that is ableto solve real-world problems of this type in short computation time. These results are of interest for practitioners in the area of communication network design. The book is addressed especially to the combinatorial optimization community, but also to those who want to learn polyhedral methods. In addition, interesting new research problemsare formulated.

  14. Heat pumps in district heating networks

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

    constraints limit the power plants. Efficient heat pumps can be used to decouple the constraints of electricity and heat production, while maintaining the high energy efficiency needed to match the politically agreed carbon emission goals. The requirements in terms of COP, location, capacity and economy...... are calculated using an energy system model which includes power plants, heat pumps and district heating consumption profiles. The model is developed with focus on accurate representation of the performance of the units in different locations and operating modes. The model can assist in investment decisions...... and strategic planning in the energy sector. The paper presents a case study of optimal implementation of heat pumps in the present energy system of the Copenhagen area. By introduction of the correct capacity of heat pumps, a 1,6 % reduction in fuel consumption for electricity and heat production can...

  15. Nature's Heat Exchangers.

    Science.gov (United States)

    Barnes, George

    1991-01-01

    Discusses the heat-transfer systems of different animals. Systems include heat conduction into the ground, heat transferred by convection, heat exchange in lizards, fish and polar animals, the carotid rete system, electromagnetic radiation from animals and people, and plant and animal fiber optics. (MDH)

  16. Transient Heat Conduction

    DEFF Research Database (Denmark)

    Rode, Carsten

    1998-01-01

    Analytical theory of transient heat conduction.Fourier's law. General heat conducation equation. Thermal diffusivity. Biot and Fourier numbers. Lumped analysis and time constant. Semi-infinite body: fixed surface temperature, convective heat transfer at the surface, or constant surface heat flux...

  17. Solar Heating Equipment

    Science.gov (United States)

    1981-01-01

    Solar Unlimited, Inc.'s suncatcher line includes a variety of solar arrays, derived from NASA's satellite program: water heating only, partial home heating, or water and whole house central heating. Solar Unlimited developed a set of vigorous requirements to avoid problems common to solar heating technologies.

  18. Rotary magnetic heat pump

    Science.gov (United States)

    Kirol, Lance D.

    1988-01-01

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation.

  19. OBESITY IN CANCER SURVIVAL

    Science.gov (United States)

    Parekh, Niyati; Chandran, Urmila; Bandera, Elisa V.

    2013-01-01

    Although obesity is a well known risk factor for several cancers, its role on cancer survival is poorly understood. We conducted a systematic literature review to assess the current evidence evaluating the impact of body adiposity on the prognosis of the three most common obesity-related cancers: prostate, colorectal, and breast. We included 33 studies of breast cancer, six studies of prostate cancer, and eight studies of colorectal cancer. We note that the evidence over-represents breast cancer survivorship research and is sparse for prostate and colorectal cancers. Overall, most studies support a relationship between body adiposity and site-specific mortality or cancer progression. However, most of the research was not specifically designed to study these outcomes and, therefore, several methodological issues should be considered before integrating their results to draw conclusions. Further research is urgently warranted to assess the long-term impact of obesity among the growing population of cancer survivors. PMID:22540252

  20. Surviving relatives after suicide

    DEFF Research Database (Denmark)

    Nørrelykke, Helle; Cohrt, Pernille

    suicide in Denmark. This means that at least 400 people undergo the trauma it is when one of their near relatives commits suicide. We also know that the loss from suicide involves a lot of conflicting feelings - like anger, shame, guilt and loss and that the lack of therapy/treatment of these difficult...... and conflicting feelings may result in pathological expansion of grief characterized by extremely reduced quality of life involving severe psychical and social consequences. Suicide a subject of taboo In the 1980s WHO drafted a health policy document (‘Health for all year 2000’) with 38 targets for attaining......We would like to focus on the surviving relatives after suicides, because it is generally accepted that it is especially difficult to recover after the loss from suicide and because we know as a fact that one suicide affects five persons on average. Every year approximately 700 people commit...

  1. Obesity in cancer survival.

    Science.gov (United States)

    Parekh, Niyati; Chandran, Urmila; Bandera, Elisa V

    2012-08-21

    Although obesity is a well-known risk factor for several cancers, its role on cancer survival is poorly understood. We conducted a systematic literature review to assess the current evidence evaluating the impact of body adiposity on the prognosis of the three most common obesity-related cancers: prostate, colorectal, and breast. We included 33 studies of breast cancer, six studies of prostate cancer, and eight studies of colo-rectal cancer. We note that the evidence overrepresents breast cancer survivorship research and is sparse for prostate and colorectal cancers. Overall, most studies support a relationship between body adiposity and site-specific mortality or cancer progression. However, most of the research was not specifically designed to study these outcomes and, therefore, several methodological issues should be considered before integrating their results to draw conclusions. Further research is urgently warranted to assess the long-term impact of obesity among the growing population of cancer survivors.

  2. Candida survival strategies.

    Science.gov (United States)

    Polke, Melanie; Hube, Bernhard; Jacobsen, Ilse D

    2015-01-01

    Only few Candida species, e.g., Candida albicans, Candida glabrata, Candida dubliniensis, and Candida parapsilosis, are successful colonizers of a human host. Under certain circumstances these species can cause infections ranging from superficial to life-threatening disseminated candidiasis. The success of C. albicans, the most prevalent and best studied Candida species, as both commensal and human pathogen depends on its genetic, biochemical, and morphological flexibility which facilitates adaptation to a wide range of host niches. In addition, formation of biofilms provides additional protection from adverse environmental conditions. Furthermore, in many host niches Candida cells coexist with members of the human microbiome. The resulting fungal-bacterial interactions have a major influence on the success of C. albicans as commensal and also influence disease development and outcome. In this chapter, we review the current knowledge of important survival strategies of Candida spp., focusing on fundamental fitness and virulence traits of C. albicans. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Psychology and survival.

    Science.gov (United States)

    Phillips, D P; Ruth, T E; Wagner, L M

    1993-11-06

    We examined the deaths of 28,169 adult Chinese-Americans, and 412,632 randomly selected, matched controls coded "white" on the death certificate. Chinese-Americans, but not whites, die significantly earlier than normal (1.3-4.9 yr) if they have a combination of disease and birthyear which Chinese astrology and medicine consider ill-fated. The more strongly a group is attached to Chinese traditions, the more years of life are lost. Our results hold for nearly all major causes of death studied. The reduction in survival cannot be completely explained by a change in the behaviour of the Chinese patient, doctor, or death-registrar, but seems to result at least partly from psychosomatic processes.

  4. Heat Roadmap Europe

    DEFF Research Database (Denmark)

    Hansen, Kenneth; Connolly, David; Lund, Henrik

    2015-01-01

    of supplying sustainable heating. Different heat production options are included in terms of individual and community heating systems. Furthermore, the levelised cost of supplying sustainable heat is estimated for both a single technology and from an energy system perspective. The results are analysed...... by assessing various parameters such as socio-economic costs and energy efficiency improvements in the national energy systems. The results demonstrate the economically feasible levels of heat savings and heat production for various European countries, highlighting differences in their national conditions......The cost of heat savings in buildings increase as more heat savings are achieved due to the state of the building stock and hence, alternatives other than savings typically become more economically feasible at a certain level of heat reductions. It is important to identify when the cost of heat...

  5. Heat Roadmap Europe 2

    DEFF Research Database (Denmark)

    Connolly, David; Mathiesen, Brian Vad; Østergaard, Poul Alberg

    Many strategies have already been proposed for the decarbonisation of the EU energy system by the year 2050. These typically focus on the expansion of renewable energy in the electricity sector and subsequently, electrifying both the heat and transport sectors as much as possible...... are identified and then, the EU27 energy system is modelled to investigate the impact of district heating. The results indicate that a combination of heat savings, district heating in urban areas, and individual heat pumps in rural areas will enable the EU27 to reach its greenhouse gas emission targets by 2050....... In these strategies, the role of district heating has never been fully explored system, nor have the benefits of district heating been quantified at the EU level. This study combines the mapping of local heat demands and local heat supplies across the EU27. Using this local knowledge, new district heating potentials...

  6. Heat Roadmap Europe

    DEFF Research Database (Denmark)

    Connolly, David; Mathiesen, Brian Vad; Lund, Henrik

    2015-01-01

    information systems (GIS) and energy system analyses. In this report, the inputs for other modelling tools such as PRIMES are presented, in order to enable other researches to generate similar heating scenarios for Europe. Although Heat Roadmap Europe presents a complete heat strategy for Europe, which...... includes energy efficiency, individual heating units (such as boilers and heat pumps), and heat networks, the recommendations here are primarily relating to the potential and modelling of district heating. Although other solutions will play a significant role in decarbonising the heating and cooling sector...... in a low-carbon energy system context, so we have focused on this area based on our extensive experience in this area [1-10]. This report includes guidelines on the potential heat demand in European buildings that can be met by district heating as well as some general guidelines on how this district...

  7. Introduction to heat transfer

    CERN Document Server

    SUNDÉN, B

    2012-01-01

    Presenting the basic mechanisms for transfer of heat, Introduction to Heat Transfer gives a deeper and more comprehensive view than existing titles on the subject. Derivation and presentation of analytical and empirical methods are provided for calculation of heat transfer rates and temperature fields as well as pressure drop. The book covers thermal conduction, forced and natural laminar and turbulent convective heat transfer, thermal radiation including participating media, condensation, evaporation and heat exchangers.

  8. Heat cascading regenerative sorption heat pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1995-01-01

    A simple heat cascading regenerative sorption heat pump process with rejected or waste heat from a higher temperature chemisorption circuit (HTCC) powering a lower temperature physisorption circuit (LTPC) which provides a 30% total improvement over simple regenerative physisorption compression heat pumps when ammonia is both the chemisorbate and physisorbate, and a total improvement of 50% or more for LTPC having two pressure stages. The HTCC contains ammonia and a chemisorbent therefor contained in a plurality of canisters, a condenser-evaporator-radiator system, and a heater, operatively connected together. The LTPC contains ammonia and a physisorbent therefor contained in a plurality of compressors, a condenser-evaporator-radiator system, operatively connected together. A closed heat transfer circuit (CHTC) is provided which contains a flowing heat transfer liquid (FHTL) in thermal communication with each canister and each compressor for cascading heat from the HTCC to the LTPC. Heat is regenerated within the LTPC by transferring heat from one compressor to another. In one embodiment the regeneration is performed by another CHTC containing another FHTL in thermal communication with each compressor. In another embodiment the HTCC powers a lower temperature ammonia water absorption circuit (LTAWAC) which contains a generator-absorber system containing the absorbent, and a condenser-evaporator-radiator system, operatively connected together. The absorbent is water or an absorbent aqueous solution. A CHTC is provided which contains a FHTL in thermal communication with the generator for cascading heat from the HTCC to the LTAWAC. Heat is regenerated within the LTAWAC by transferring heat from the generator to the absorber. The chemical composition of the chemisorbent is different than the chemical composition of the physisorbent, and the absorbent. The chemical composition of the FHTL is different than the chemisorbent, the physisorbent, the absorbent, and ammonia.

  9. Heat stroke and related heat stress disorders.

    Science.gov (United States)

    Knochel, J P

    1989-05-01

    Medical disorders related to environmental heat exposure are exceptionally common in persons who perform hard work in hot climates. They are also common in competitive athletes as well as in persons who participate in casual exercise to maintain health. The important issue of salt and water disturbances consequent to heavy sweating in hot climates is discussed in detail as are mechanisms of potassium deficiency and its implications. The major forms of environmental heat illness including heat syncope, heat cramp, heat exhaustion, and heat stroke are presented in detail with relevant clinical examples. A discussion of the differential diagnosis of hyperthermia and rhabdomyolysis follows. Because of the difference in treatment and complications, heat stroke is subdivided into the classic variety that affects the elderly and very young and that form that follows heavy physical work and is always associated with rhabdomyolysis. Because severe heat exhaustion and heat stroke are life-threatening disorders, the chapter includes a detailed discussion of complications and plans for treatment.

  10. Heat Pipe Technology

    Science.gov (United States)

    1981-01-01

    The heat pipe, a sealed chamber whose walls are lined with a "wick," a thin capillary network containing a working fluid in liquid form was developed for a heat distribution system for non-rotating satellites. Use of the heat pipe provides a continuous heat transfer mechanism. "Heat tubes" that improve temperature control in plastics manufacturing equipment incorporated the heat pipe technology. James M. Stewart, an independent consultant, patented the heat tubes he developed and granted a license to Kona Corporation. The Kona Nozzle for heaterless injection molding gets heat for its operation from an external source and has no internal heating bands, reducing machine maintenance and also eliminating electrical hazards associated with heater bands. The nozzles are used by Eastman Kodak, Bic Pen Corporation, Polaroid, Tupperware, Ford Motor Company, RCA, and Western Electric in the molding of their products.

  11. Survival assays using Caenorhabditis elegans.

    Science.gov (United States)

    Park, Hae-Eun H; Jung, Yoonji; Lee, Seung-Jae V

    2017-02-01

    Caenorhabditis elegans is an important model organism with many useful features, including rapid development and aging, easy cultivation, and genetic tractability. Survival assays using C. elegans are powerful methods for studying physiological processes. In this review, we describe diverse types of C. elegans survival assays and discuss the aims, uses, and advantages of specific assays. C. elegans survival assays have played key roles in identifying novel genetic factors that regulate many aspects of animal physiology, such as aging and lifespan, stress response, and immunity against pathogens. Because many genetic factors discovered using C. elegans are evolutionarily conserved, survival assays can provide insights into mechanisms underlying physiological processes in mammals, including humans.

  12. Surviving a Suicide Attempt

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Harrasi

    2016-09-01

    Full Text Available Suicide is a global phenomenon in all regions of the world affecting people of all age groups. It has detrimental consequences on patients, their families, and the community as a whole. There have been numerous risk factors described for suicide including mental illness, stressful life situations, loss of social support, and general despair. The association of suicide with Islam has not been extensively studied. The common impression from clinical practice is that being a practicing Muslim reduces the risk of suicide. Another factor associated with suicide is starting a patient on antidepressants. However, this has been questioned recently. This report describes a middle-aged man with depression and multiple social stressors who survived a serious suicide attempt. The discussion will focus on the factors that lead him to want to end his life and the impact of the assumed protective factors such as religious belief and family support on this act of self-harm. Such patients can be on the edge when there is an imbalance between risk factors (such as depression, insomnia, and psychosocial stressors and protective factors (like religious affiliation and family support. All physicians are advised to assess the suicide risk thoroughly in patients with depression regardless of any presumed protective factor.

  13. Surviving a Suicide Attempt.

    Science.gov (United States)

    Al-Harrasi, Ahmed; Al Maqbali, Mandhar; Al-Sinawi, Hamed

    2016-09-01

    Suicide is a global phenomenon in all regions of the world affecting people of all age groups. It has detrimental consequences on patients, their families, and the community as a whole. There have been numerous risk factors described for suicide including mental illness, stressful life situations, loss of social support, and general despair. The association of suicide with Islam has not been extensively studied. The common impression from clinical practice is that being a practicing Muslim reduces the risk of suicide. Another factor associated with suicide is starting a patient on antidepressants. However, this has been questioned recently. This report describes a middle-aged man with depression and multiple social stressors who survived a serious suicide attempt. The discussion will focus on the factors that lead him to want to end his life and the impact of the assumed protective factors such as religious belief and family support on this act of self-harm. Such patients can be on the edge when there is an imbalance between risk factors (such as depression, insomnia, and psychosocial stressors) and protective factors (like religious affiliation and family support). All physicians are advised to assess the suicide risk thoroughly in patients with depression regardless of any presumed protective factor.

  14. Will the olympics survive?.

    Science.gov (United States)

    Khosla, T.

    1977-01-01

    The United States of America dominated 58 events in athletics, field and swimming, which between them accounted for 35 per cent of all events in the Munich Olympiad. 1972; these events favour taller individuals. But, in 25 per cent of other events (1) cycling, (2) fencing, (3) gymnastics, (4) judo, (5) weightlifting and (6) Graeco Roman wrestling the U.S.A. did not win a single medal. The failure of the U.S.A. to maintain her lead in Munich was largely due to weaknesses in these other events in many of which the potential medallists can be derived from the lower half of the height distribution (events 3 to 6). These weaknesses are Russia's strength and they continued to remain unstrengthened at Montreal. Also, the domination held by the U.S.A. in swimming was seriously challenged by East Germany. The present trends indicate that the U.S.A.'s ranking is likely to slip further to the third position in Moscow 1980. Factors inhibiting the survival of the Olympics are pointed. PMID:861436

  15. Basic heat transfer

    CERN Document Server

    Bacon, D H

    2013-01-01

    Basic Heat Transfer aims to help readers use a computer to solve heat transfer problems and to promote greater understanding by changing data values and observing the effects, which are necessary in design and optimization calculations.The book is concerned with applications including insulation and heating in buildings and pipes, temperature distributions in solids for steady state and transient conditions, the determination of surface heat transfer coefficients for convection in various situations, radiation heat transfer in grey body problems, the use of finned surfaces, and simple heat exc

  16. Ideal Heat Exchange System

    Science.gov (United States)

    Tsirlin, A. M.

    2017-09-01

    The requirements with which a heat exchange system should comply in order that at certain values of the total contact surface and heat load the entropy production in it should be minimal have been determined. It has been shown that this system can serve as a standard for real systems of irreversible heat exchange. We have found the conditions for physical realizability of a heat exchange system in which heat exchange occurs by a law linear with respect to the temperature difference between contacting flows. Analogous conditions are given without deriving for the case of heat exchange by the Fourier law.

  17. Microscale Regenerative Heat Exchanger

    Science.gov (United States)

    Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

    2006-01-01

    The device described herein is designed primarily for use as a regenerative heat exchanger in a miniature Stirling engine or Stirling-cycle heat pump. A regenerative heat exchanger (sometimes called, simply, a "regenerator" in the Stirling-engine art) is basically a thermal capacitor: Its role in the Stirling cycle is to alternately accept heat from, then deliver heat to, an oscillating flow of a working fluid between compression and expansion volumes, without introducing an excessive pressure drop. These volumes are at different temperatures, and conduction of heat between these volumes is undesirable because it reduces the energy-conversion efficiency of the Stirling cycle.

  18. Survival of microbial life under shock compression: implications for Panspermia

    Science.gov (United States)

    Burchell, M.

    2007-09-01

    An analysis is carried out of the survival fraction of micro-organisms exposed to extreme shock pressures. A variety of data sources are used in this analysis. The key findings are that survival depends on the behaviour of the cell wall. Below a critical shock pressure there is a relatively slow fall in survival fraction as shock pressures increase. Above the critical threshold survival starts to fall rapidly as shock pressure increases further. The critical shock pressures found here are in the range 2.4 to 20 GPa, and vary not only from organism to organism, but also depend on the growth stage of given organisms, with starved (i.e., no growth) states favoured for survival. At the shock pressures typical of those involved in interplanetary transfer of rocky materials, the survival fractions are found to be small but finite. This lends credence to the idea of Panspermia, i.e. life may naturally migrate through space. Thus for example, Martian meteorites should not a prior be considered as sterile due to the shock processes they have undergone, but their lack of viable micro-organisms either reflects no such life being present at the source at the time of departure or the influence of other hazardous processes such as radiation in space or heating of surfaces during entry into a planetary atmosphere.

  19. Survival After Relapse of Medulloblastoma.

    Science.gov (United States)

    Koschmann, Carl; Bloom, Karina; Upadhyaya, Santhosh; Geyer, J Russell; Leary, Sarah E S

    2016-05-01

    Survival after recurrence of medulloblastoma has not been reported in an unselected cohort of patients in the contemporary era. We reviewed 55 patients diagnosed with medulloblastoma between 2000 and 2010, and treated at Seattle Children's Hospital to evaluate patterns of relapse treatment and survival. Fourteen of 47 patients (30%) over the age of 3 experienced recurrent or progressive medulloblastoma after standard therapy. The median time from diagnosis to recurrence was 18.0 months (range, 3.6 to 62.6 mo), and site of recurrence was metastatic in 86%. The median survival after relapse was 10.3 months (range, 1.3 to 80.5 mo); 3-year survival after relapse was 18%. There were trend associations between longer survival and having received additional chemotherapy (median survival 12.8 vs. 1.3 mo, P=0.16) and radiation therapy (15.4 vs. 5.9 mo, P=0.20). Isolated local relapse was significantly associated with shorter survival (1.3 vs. 12.8 mo, P=0.009). Recurrence of medulloblastoma is more likely to be metastatic than reported in previous eras. Within the limits of our small sample, our data suggest a potential survival benefit from retreatment with cytotoxic chemotherapy and radiation even in heavily pretreated patients. This report serves as a baseline against which to evaluate novel therapy combinations.

  20. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Be Prepared Safe Citizen Day Organize Important Medical Information ER Checklists Preparing for Emergencies Be ready to ... anyone can be affected. Here you will find information about heat cramps and heat stroke and exhaustion. ...

  1. Heat Roadmap Europe

    DEFF Research Database (Denmark)

    David, Andrei; Mathiesen, Brian Vad; Averfalk, Helge

    2017-01-01

    The Heat Roadmap Europe (HRE) studies estimated a potential increase of the district heating (DH) share to 50% of the entire heat demand by 2050, with approximately 25–30% of it being supplied using large-scale electric heat pumps. This study builds on this potential and aims to document...... that such developments can begin now with technologies currently available. We present a database and the status of the technology and its ability of expansion to other European locations by reviewing experiences aimed at further research or application in the heating industry. This is based on a survey of the existing...... capacity of electric large-scale heat pumps with more than 1 MW thermal output, operating in European DH systems. The survey is the first database of its kind containing the technical characteristics of these heat pumps, and provides the basis for the analysis of this paper. By quantifying the heat sources...

  2. Convective heat transfer

    CERN Document Server

    Kakac, Sadik; Pramuanjaroenkij, Anchasa

    2014-01-01

    Intended for readers who have taken a basic heat transfer course and have a basic knowledge of thermodynamics, heat transfer, fluid mechanics, and differential equations, Convective Heat Transfer, Third Edition provides an overview of phenomenological convective heat transfer. This book combines applications of engineering with the basic concepts of convection. It offers a clear and balanced presentation of essential topics using both traditional and numerical methods. The text addresses emerging science and technology matters, and highlights biomedical applications and energy technologies. What’s New in the Third Edition: Includes updated chapters and two new chapters on heat transfer in microchannels and heat transfer with nanofluids Expands problem sets and introduces new correlations and solved examples Provides more coverage of numerical/computer methods The third edition details the new research areas of heat transfer in microchannels and the enhancement of convective heat transfer with nanofluids....

  3. Heat resistant microorganism

    NARCIS (Netherlands)

    Berendsen, Erwin M.; Bennik, Maria H.J.; Kuipers, Oscar

    2015-01-01

    The invention relates to a kit and methods and means for the determination of the presence of heat resistant organisms. The invention further relates to the provision organisms wherein the heat resistance is modulated.

  4. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... heat stroke and exhaustion. Heat Cramps Symptoms include muscle spasms, usually in the legs and stomach area. ... Z Teeth (Dental Emergencies) Sprains and Strains Head Injury Resources Home Safety Checklist ACEP Coloring Book Download ...

  5. Genetic Algorithm Design of a 3D Printed Heat Sink

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Tong [ORNL; Ozpineci, Burak [ORNL; Ayers, Curtis William [ORNL

    2016-01-01

    In this paper, a genetic algorithm- (GA-) based approach is discussed for designing heat sinks based on total heat generation and dissipation for a pre-specified size andshape. This approach combines random iteration processesand genetic algorithms with finite element analysis (FEA) to design the optimized heat sink. With an approach that prefers survival of the fittest , a more powerful heat sink can bedesigned which can cool power electronics more efficiently. Some of the resulting designs can only be 3D printed due totheir complexity. In addition to describing the methodology, this paper also includes comparisons of different cases to evaluate the performance of the newly designed heat sinkcompared to commercially available heat sinks.

  6. Isolated quantum heat engine.

    Science.gov (United States)

    Fialko, O; Hallwood, D W

    2012-02-24

    We present a theoretical and numerical analysis of a quantum system that is capable of functioning as a heat engine. This system could be realized experimentally using cold bosonic atoms confined to a double well potential that is created by splitting a harmonic trap with a focused laser. The system shows thermalization, and can model a reversible heat engine cycle. This is the first demonstration of the operation of a heat engine with a finite quantum heat bath.

  7. Isolated quantum heat engine

    OpenAIRE

    Fialko, O.; Hallwood, D.

    2011-01-01

    We present a theoretical and numerical analysis of a quantum system that is capable of functioning as a heat engine. This system could be realized experimentally using cold bosonic atoms confined to a double well potential that is created by splitting a harmonic trap with a focused laser. The system shows thermalization, and can model a reversible heat engine cycle. This is the first demonstration of the operation of a heat engine with a finite quantum heat bath.

  8. Solar heat receiver

    Science.gov (United States)

    Hunt, Arlon J.; Hansen, Leif J.; Evans, David B.

    1985-01-01

    A receiver for converting solar energy to heat a gas to temperatures from 700.degree.-900.degree. C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

  9. Natural Thermoelectric Heat Pump in Social Wasps

    Science.gov (United States)

    Ishay, Jacob S.; Pertsis, Vitaly; Rave, Eran; Goren, Alon; Bergman, David J.

    2003-05-01

    Photographs of wasps or hornets, taken with different temperature sensitive infrared cameras, reveal body temperatures that are sometimes significantly lower than the ambient temperature. This suggests that the hornets possess an intrinsic biological heat pump mechanism which can be used to achieve such cooling. Evidence is presented to substantiate this novel suggestion and to argue that the heat pump is most likely implemented by exploiting a thermoelectric effect in the hornet cuticle. Such a natural heat pump can conceivably also serve to cool the active hornet, engaged in daytime activities outside the nest at ambient temperatures exceeding 40 °C, to a body temperature that is low enough to allow its survival in extreme thermal conditions. It might also function as a means of raising the body temperature up to a level that enables the hornet to remain active even when the ambient temperature is as low as 10 °C.

  10. Natural thermoelectric heat pump in social wasps.

    Science.gov (United States)

    Ishay, Jacob S; Pertsis, Vitaly; Rave, Eran; Goren, Alon; Bergman, David J

    2003-05-30

    Photographs of wasps or hornets, taken with different temperature sensitive infrared cameras, reveal body temperatures that are sometimes significantly lower than the ambient temperature. This suggests that the hornets possess an intrinsic biological heat pump mechanism which can be used to achieve such cooling. Evidence is presented to substantiate this novel suggestion and to argue that the heat pump is most likely implemented by exploiting a thermoelectric effect in the hornet cuticle. Such a natural heat pump can conceivably also serve to cool the active hornet, engaged in daytime activities outside the nest at ambient temperatures exceeding 40 degrees C, to a body temperature that is low enough to allow its survival in extreme thermal conditions. It might also function as a means of raising the body temperature up to a level that enables the hornet to remain active even when the ambient temperature is as low as 10 degrees C.

  11. Heat-Related Illnesses

    Science.gov (United States)

    ... this! Home » Emergency 101 Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at Mercy Health System in Chesterfield, Missouri Heat-related illness can be caused by overexposure to the sun or any situation that involves extreme heat. Young children and the elderly are most at risk, ...

  12. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... this! Home » Emergency 101 Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at Mercy Health System in Chesterfield, Missouri Heat-related illness can be caused by overexposure to the sun or any situation that involves extreme heat. Young children and the elderly are most at risk, ...

  13. Heat roadmap China

    DEFF Research Database (Denmark)

    Xiong, Weiming; Wang, Yu; Mathiesen, Brian Vad

    2015-01-01

    District heating is regarded as a key element of energy saving actions in the Chinese national energy strategy, while space heating in China is currently still dominated by coal boilers. However, there is no existing quantitative study to analyse the future heat strategy for China. Therefore...

  14. Microwave processing heats up

    Science.gov (United States)

    Microwaves are a common appliance in many households. In the United States microwave heating is the third most popular domestic heating method food foods. Microwave heating is also a commercial food processing technology that has been applied for cooking, drying, and tempering foods. It's use in ...

  15. Single Electrode Heat Effects

    DEFF Research Database (Denmark)

    Jacobsen, Torben; Broers, G. H. J.

    1977-01-01

    The heat evolution at a single irreversibly working electrode is treated onthe basis of the Brønsted heat principle. The resulting equation is analogous to the expression for the total heat evolution in a galvanic cellwith the exception that –DeltaS is substituted by the Peltier entropy, Delta...

  16. Champagne Heat Pump

    Science.gov (United States)

    Jones, Jack A.

    2004-01-01

    The term champagne heat pump denotes a developmental heat pump that exploits a cycle of absorption and desorption of carbon dioxide in an alcohol or other organic liquid. Whereas most heat pumps in common use in the United States are energized by mechanical compression, the champagne heat pump is energized by heating. The concept of heat pumps based on other absorption cycles energized by heat has been understood for years, but some of these heat pumps are outlawed in many areas because of the potential hazards posed by leakage of working fluids. For example, in the case of the water/ammonia cycle, there are potential hazards of toxicity and flammability. The organic-liquid/carbon dioxide absorption/desorption cycle of the champagne heat pump is similar to the water/ammonia cycle, but carbon dioxide is nontoxic and environmentally benign, and one can choose an alcohol or other organic liquid that is also relatively nontoxic and environmentally benign. Two candidate nonalcohol organic liquids are isobutyl acetate and amyl acetate. Although alcohols and many other organic liquids are flammable, they present little or no flammability hazard in the champagne heat pump because only the nonflammable carbon dioxide component of the refrigerant mixture is circulated to the evaporator and condenser heat exchangers, which are the only components of the heat pump in direct contact with air in habitable spaces.

  17. Heat pipes for industrial waste heat recovery

    Science.gov (United States)

    Merrigan, M. A.

    1981-01-01

    Development work on the high temperature ceramic recuperator at Los Alamos National Laboratory is described and involved material investigations, fabrication methods development, compatibility tests, heat pipe operation, and the modeling of application conditions based on current industrial usage. Solid ceramic heat pipes, ceramic coated refractory pipes, and high-temperature oxide protected metallic pipes are investigated. Economic studies of the use of heat pipe based recuperators in industrial furnaces are conducted and payback periods determined as a function of material, fabrication, and installation cost.

  18. Geothermal heat in a heat pump use

    Science.gov (United States)

    Pavlova, A.; Hansen, J.; Obermeyer, H.; Pavlova, I.

    2016-09-01

    The considered innovative technology proposes to use alternative energy sources for the process efficiency in low-height construction. The world economy depends on price rises for energy sources and the danger of environmental pollution increases. Geothermal energy is the basic resource saving and environmentally safe renewable heat source that is characterized by inexhaustibility, permanent all the-year-round use, universal prevalence of resources and the ability to replace considerable volumes of traditional energy carriers. The expediency and power efficiency to apply a heat pump with the use of geothermal heat is proved for low-height construction.

  19. Marketing child survival.

    Science.gov (United States)

    Grant, J P

    1984-01-01

    Growth monitoring charts, packets of oral rehydration salts (ORS), and vaccines, are inexpensive, life-saving, growth-protecting technologies which can enable parents to protect their children against the worst effects of poverty. Similarly, a matrix of current and easily understandable information about pregnancy, breast feeding, weaning, feeding during and immediately after illness, child spacing, and preparing and using home-made oral rehydration solutions, also could empower parents to protect the lives and the health of their children. The question arises as to how can these technologies and this information be put at the disposal of millions of families in the low-income world. The initial task of the Child Survival and Development Revolution is the communication of what is now possible, yet little is known about how to communicate information whose principal value is to the poor. There are 2 large-scale precedents: the Green Revolution, which in many instances succeeded in putting into the hands of thousands of small and large farmers the techniques and the knowledge which enabled them to double and treble the yields from their lands; and the campaign to put the knowledge and the means of family planning at the disposal of many millions of people. There are 2 lessons to be learned from these precedents: they have shown that the way to promote a people's technology and to put information at the disposal of the majority is by mobilizing all possible resources and working through all possible channels both to create the demand and to meet it; and neither the Green Revolution nor the family planning movement rally took off until they were viewed as political and economic priorities and given the full support of the nation's political leadership. Nowhere are these 2 lessons more clearly illustrated than in present-day Indonesia. Because the campaign for family planning was given high personal and political priority by the President, and because 85% of all family

  20. Intelligent urban heating

    Energy Technology Data Exchange (ETDEWEB)

    Dyrelund, A.

    2011-05-15

    In smart cities District heating is a precondition for large scale and cost effective integration of CHP and renewable energy for heating in urban areas. In particular, district heating systems combined with CHP, heat pumps, electric boilers and large thermal storages is important for efficient integration of fluctuating wind energy. In order to develop an intelligent and cost effective urban heating system it is important to integrate and optimize the total urban heating energy system including building envelope, heating installations, district heating networks, heat storages and renewable energy sources. Two examples: 1) the variable long term production cost is a basic parameter for the optimal building envelope. 2) efficient low temperature heating installations increases the efficiency of the district heating distribution network and all the low temperature heat sources. Besides, in districts with a cooling load, it is important to include the district cooling in the optimized energy system, both for production and end-use. In EU countries, the Renewable energy directive encourage all local authorities to plan for urban heating and cooling in order to provide the buildings with renewable energy for heating hot tap water and cooling via this infrastructure, whenever it is cost effective compared to individual solutions. Ramboll has in association with Aalborg University prepared an updated study of Heat Plan Denmark in 2010. The study demonstrates how the Danish Heating sector has reduced the fossil fuel consumption to 40% from 1980 to 2010 and how the sector can be independent of fossil fuels before 2030 in a cost effective way. The study concludes that it is necessary to optimize investments both at the supply and the demand side. It is estimated that an optimal combination could be 25 % additional heat demand reduction, further reduction of the return temperature in the building installations, expansion of district heating from 50 to 65 %, local heating up

  1. Chemical heat pump

    Science.gov (United States)

    Greiner, Leonard

    1980-01-01

    A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer. The heat pump part of the system heats or cools a house or other structure through a combination of evaporation and absorption or, conversely, condensation and desorption, in a pair of containers. A set of automatic controls change the system for operation during winter and summer months and for daytime and nighttime operation to satisfactorily heat and cool a house during an entire year. The absorber chamber is subjected to solar heating during regeneration cycles and is covered by one or more layers of glass or other transparent material. Daytime home air used for heating the home is passed at appropriate flow rates between the absorber container and the first transparent cover layer in heat transfer relationship in a manner that greatly reduce eddies and resultant heat loss from the absorbant surface to ambient atmosphere.

  2. District Heating System Using Heat Pump Installations and CHP

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2015-12-01

    Full Text Available The article describes the district heating system, in which part of the heat of return water thermal power is used to supply heat to the district heating puThe article describes the district heating system, in which part of the heat of return water thermal power is used to supply heat to the district heating pumps, evaporators heating and hot water. Heat pumps use carbon dioxide as refrigerant. During the transitional period of the year, and the summer heat pump for preparing hot-water supply system uses the heat of the surrounding air. The heat of the ambient air is used in the intermediate heat exchanger between the first and second stages of the heat pump to cool the gas after the first stage of the compressor of the heat pump.

  3. "E" Heating Head

    Science.gov (United States)

    Fox, Robert L.; Swaim, Robert J.; Johnson, Samuel D.; Coultrip, Robert H.; Phillips, W. Morris; Copeland, Carl E.

    1994-01-01

    Two separate areas heated inductively for adhesive bonding in single operation. "E" heating head developed to satisfy need for fast-acting and reliable induction heating device. Used in attaching "high-hat" stiffeners to aircraft panels. Incorporates principles and circuitry of toroid joining gun. Width and length configured to provide variously sized heat zones, depending on bonding requirements. Lightweight, portable and provides rapid, reliable heating of dual areas in any environment. Well suited for flight-line and depot maintenance, and battlefield repair. Also useful in automotive assembly lines to strengthen automobile panels.

  4. Absorption heat pump system

    Science.gov (United States)

    Grossman, Gershon; Perez-Blanco, Horacio

    1984-01-01

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  5. Heat Rash (Prickly Heat or Miliaria)

    Science.gov (United States)

    ... Baby rashes Heat rash Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  6. Description of heat flux measurement methods used in hydrocarbon and propellant fuel fires at Sandia.

    Energy Technology Data Exchange (ETDEWEB)

    Nakos, James Thomas

    2010-12-01

    The purpose of this report is to describe the methods commonly used to measure heat flux in fire applications at Sandia National Laboratories in both hydrocarbon (JP-8 jet fuel, diesel fuel, etc.) and propellant fires. Because these environments are very severe, many commercially available heat flux gauges do not survive the test, so alternative methods had to be developed. Specially built sensors include 'calorimeters' that use a temperature measurement to infer heat flux by use of a model (heat balance on the sensing surface) or by using an inverse heat conduction method. These specialty-built sensors are made rugged so they will survive the environment, so are not optimally designed for ease of use or accuracy. Other methods include radiometers, co-axial thermocouples, directional flame thermometers (DFTs), Sandia 'heat flux gauges', transpiration radiometers, and transverse Seebeck coefficient heat flux gauges. Typical applications are described and pros and cons of each method are listed.

  7. Heat pipe cooling system with sensible heat sink

    Science.gov (United States)

    Silverstein, Calvin C.

    1988-01-01

    A heat pipe cooling system which employs a sensible heat sink is discussed. With this type of system, incident aerodynamic heat is transported via a heat pipe from the stagnation region to the heat sink and absorbed by raising the temperature of the heat sink material. The use of a sensible heat sink can be advantageous for situations where the total mission heat load is limited, as it is during re-entry, and a suitable radiation sink is not available.

  8. Heat pump apparatus

    Science.gov (United States)

    Nelson, Paul A.; Horowitz, Jeffrey S.

    1983-01-01

    A heat pump apparatus including a compact arrangement of individual tubular reactors containing hydride-dehydride beds in opposite end sections, each pair of beds in each reactor being operable by sequential and coordinated treatment with a plurality of heat transfer fluids in a plurality of processing stages, and first and second valves located adjacent the reactor end sections with rotatable members having multiple ports and associated portions for separating the hydride beds at each of the end sections into groups and for simultaneously directing a plurality of heat transfer fluids to the different groups. As heat is being generated by a group of beds, others are being regenerated so that heat is continuously available for space heating. As each of the processing stages is completed for a hydride bed or group of beds, each valve member is rotated causing the heat transfer fluid for the heat processing stage to be directed to that bed or group of beds. Each of the end sections are arranged to form a closed perimeter and the valve member may be rotated repeatedly about the perimeter to provide a continuous operation. Both valves are driven by a common motor to provide a coordinated treatment of beds in the same reactors. The heat pump apparatus is particularly suitable for the utilization of thermal energy supplied by solar collectors and concentrators but may be used with any source of heat, including a source of low-grade heat.

  9. Heat Roadmap Europe

    DEFF Research Database (Denmark)

    Connolly, David; Lund, Henrik; Mathiesen, Brian Vad

    2014-01-01

    for district heating in the EU between now and 2050 is identified, based on extensive and detailed mapping of the EU heat demand and various supply options. Subsequently, a new ‘district heating plus heat savings’ scenario is technically and economically assessed from an energy systems perspective. The results...... indicate that with district heating, the EU energy system will be able to achieve the same reductions in primary energy supply and carbon dioxide emissions as the existing alternatives proposed. However, with district heating these goals can be achieved at a lower cost, with heating and cooling costs......Six different strategies have recently been proposed for the European Union (EU) energy system in the European Commission's report, Energy Roadmap 2050. The objective for these strategies is to identify how the EU can reach its target of an 80% reduction in annual greenhouse gas emissions in 2050...

  10. Space Heating Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, Kevin D.

    1998-01-01

    The performance evaluation of space heating equipment for a geothermal application is generally considered from either of two perspectives: (a) selecting equipment for installation in new construction, or (b) evaluating the performance and retrofit requirements of an existing system. With regard to new construction, the procedure is relatively straightforward. Once the heating requirements are determined, the process need only involve the selection of appropriately sized hot water heating equipment based on the available water temperature. It is important to remember that space heating equipment for geothermal applications is the same equipment used in non-geothermal applications. What makes geothermal applications unique is that the equipment is generally applied at temperatures and flow rates that depart significantly from traditional heating system design. This chapter presents general considerations for the performance of heating equipment at non-standard temperature and flow conditions, retrofit of existing systems, and aspects of domestic hot water heating.

  11. Global Activities and Plant Survival

    DEFF Research Database (Denmark)

    Bandick, Roger

    2014-01-01

    This chapter provides an extensive review of the empirical evidence found for Sweden concerning plant survival. The result reveals that foreign MNE plants and exporting non-MNE plants have the lowest exit rates, followed by purely domestic-oriented plants, and that domestic MNE plants have...... the highest exit rates. Moreover, the exit rates of globally engaged plants seem to be unaffected by increased foreign presence, whereas there appears to be a negative impact on the survival rates of non-exporting non-MNE plants. Finally, the result reveals that the survival ratio of plants of acquired...... exporters, but not other types of plants, improves post acquisition....

  12. Cardiovascular disease incidence and survival

    DEFF Research Database (Denmark)

    Byberg, Stine; Agyemang, Charles; Zwisler, Ann Dorthe

    2016-01-01

    Studies on cardiovascular disease (CVD) incidence and survival show varying results between different ethnic groups. Our aim was to add a new dimension by exploring the role of migrant status in combination with ethnic background on incidence of-and survival from-CVD and more specifically acute...... of some types of cardiovascular disease compared to Danish-born. Family-reunified migrants on the other hand had lower rates of CVD. All migrants had better survival than Danish-born indicating that migrants may not always be disadvantaged in health....

  13. [Physical activity and cancer survival].

    Science.gov (United States)

    Romieu, Isabelle; Touillaud, Marina; Ferrari, Pietro; Bignon, Yves-Jean; Antoun, Sami; Berthouze-Aranda, Sophie; Bachmann, Patrick; Duclos, Martine; Ninot, Grégory; Romieu, Gilles; Sénesse, Pierre; Behrendt, Jan; Balosso, Jacques; Pavic, Michel; Kerbrat, Pierre; Serin, Daniel; Trédan, Olivier; Fervers, Béatrice

    2012-10-01

    Physical activity has been shown in large cohort studies to positively impact survival in cancer survivors. Existing randomized controlled trials showed a beneficial effect of physical activity on physical fitness, quality of life, anxiety and self-esteem; however, the small sample size, the short follow-up and the lack of standardization of physical activity intervention across studies impaired definite conclusion in terms of survival. Physical activity reduces adiposity and circulating estrogen levels and increases insulin sensitivity among other effects. A workshop was conducted at the International Agency for Research on Cancer in April 2011 to discuss the role of physical activity on cancer survival and the methodology to develop multicentre randomized intervention trials, including the type of physical activity to implement and its association with nutritional recommendations. The authors discuss the beneficial effect of physical activity on cancer survival with a main focus on breast cancer and report the conclusions from this workshop.

  14. Operational slack and venture survival

    OpenAIRE

    Azadegan, Arash; Patel, Pankaj; Parida, Vinit

    2013-01-01

    Slack can act as a double-edged sword. While it can buffer against environmental threats to help ensure business continuity, slack canalso be costly and reduce profitability. In this study, we focus on operational slack, the form related to the firm’s production processes. We investigate the role of operational slack on firm survival during its venture stage, when its survival is significantly challenged by environmental threats. Specifically, we explore how change in three types of environme...

  15. Stochastic and deterministic model of microbial heat inactivation.

    Science.gov (United States)

    Corradini, Maria G; Normand, Mark D; Peleg, Micha

    2010-03-01

    Microbial inactivation is described by a model based on the changing survival probabilities of individual cells or spores. It is presented in a stochastic and discrete form for small groups, and as a continuous deterministic model for larger populations. If the underlying mortality probability function remains constant throughout the treatment, the model generates first-order ("log-linear") inactivation kinetics. Otherwise, it produces survival patterns that include Weibullian ("power-law") with upward or downward concavity, tailing with a residual survival level, complete elimination, flat "shoulder" with linear or curvilinear continuation, and sigmoid curves. In both forms, the same algorithm or model equation applies to isothermal and dynamic heat treatments alike. Constructing the model does not require assuming a kinetic order or knowledge of the inactivation mechanism. The general features of its underlying mortality probability function can be deduced from the experimental survival curve's shape. Once identified, the function's coefficients, the survival parameters, can be estimated directly from the experimental survival ratios by regression. The model is testable in principle but matching the estimated mortality or inactivation probabilities with those of the actual cells or spores can be a technical challenge. The model is not intended to replace current models to calculate sterility. Its main value, apart from connecting the various inactivation patterns to underlying probabilities at the cellular level, might be in simulating the irregular survival patterns of small groups of cells and spores. In principle, it can also be used for nonthermal methods of microbial inactivation and their combination with heat.

  16. Optimization of Heat Exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Ivan Catton

    2010-10-01

    The objective of this research is to develop tools to design and optimize heat exchangers (HE) and compact heat exchangers (CHE) for intermediate loop heat transport systems found in the very high temperature reator (VHTR) and other Generation IV designs by addressing heat transfer surface augmentation and conjugate modeling. To optimize heat exchanger, a fast running model must be created that will allow for multiple designs to be compared quickly. To model a heat exchanger, volume averaging theory, VAT, is used. VAT allows for the conservation of mass, momentum and energy to be solved for point by point in a 3 dimensional computer model of a heat exchanger. The end product of this project is a computer code that can predict an optimal configuration for a heat exchanger given only a few constraints (input fluids, size, cost, etc.). As VAT computer code can be used to model characteristics )pumping power, temperatures, and cost) of heat exchangers more quickly than traditional CFD or experiment, optimization of every geometric parameter simultaneously can be made. Using design of experiment, DOE and genetric algorithms, GE, to optimize the results of the computer code will improve heat exchanger disign.

  17. Heat pump system

    Science.gov (United States)

    Swenson, Paul F.; Moore, Paul B.

    1977-01-01

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  18. Floor heating maximizes residents` comfort

    Energy Technology Data Exchange (ETDEWEB)

    Tirkkanen, P.; Wikstroem, T.

    1996-11-01

    Storing heat in floors by using economical night-time electricity does not increase the specific consumption of heating. According to studies done by IVO, the optimum housing comfort is achieved if the room is heated mainly by means of floor heating that is evened out by window or ceiling heating, or by a combination of all three forms of heating. (orig.)

  19. Roles of heat shock factors in gametogenesis and development.

    Science.gov (United States)

    Abane, Ryma; Mezger, Valérie

    2010-10-01

    Heat shock factors form a family of transcription factors (four in mammals), which were named according to the first discovery of their activation by heat shock. As a result of the universality and robustness of their response to heat shock, the stress-dependent activation of heat shock factor became a ‘paradigm’: by binding to conserved DNA sequences (heat shock elements), heat shock factors trigger the expression of genes encoding heat shock proteins that function as molecular chaperones, contributing to establish a cytoprotective state to various proteotoxic stress and in several pathological conditions. Besides their roles in the stress response, heat shock factors perform crucial roles during gametogenesis and development in physiological conditions. First, during these process, in stress conditions, they are either proactive for survival or, conversely, for apoptotic process, allowing elimination or, inversely, protection of certain cell populations in a way that prevents the formation of damaged gametes and secure future reproductive success. Second, heat shock factors display subtle interplay in a tissue- and stage-specific manner, in regulating very specific sets of heat shock genes, but also many other genes encoding growth factors or involved in cytoskeletal dynamics. Third, they act not only by their classical transcription factor activities, but are necessary for the establishment of chromatin structure and, likely, genome stability. Finally, in contrast to the heat shock gene paradigm, heat shock elements bound by heat shock factors in developmental process turn out to be extremely dispersed in the genome, which is susceptible to lead to the future definition of ‘developmental heat shock element’.

  20. Plasma heat pump and heat engine

    Science.gov (United States)

    Avinash, K.

    2010-08-01

    A model system where cold charged particles are locally confined in a volume VP within a warm plasma of volume V (VP≪V) is studied. Charged particles mutually repel via a shielded repulsion which is like an effective pressure, i.e., electrostatic pressure PE. The law of thermodynamics involving PE and an equation of state for PE are obtained. It is shown that the expansion/compression of electrostatic fields associated with charged particles is a new mechanism that converts mechanical work into plasma heat and vice versa. Two applications of this theory are, first we propose a pumping device which heats plasmas by an adiabatic/isothermal compression of fields. Heating power ranging from a few hundred watts to a few kilowatts is possible with the present day technology. Second, we discuss the feasibility of constructing an electrostatic heat engine which converts plasma heat into mechanical work via plasma electric fields. Effects of PE are shown to be observable in colloidal solutions.

  1. Heat Roadmap Europe

    DEFF Research Database (Denmark)

    Connolly, David

    2017-01-01

    This paper compares the electricity, heating, and cooling sectors at national level for various European countries. Annual energy demands are compared for all 28 EU countries, while peak hourly demands are compared for four countries that vary significantly. The results indicate that the heat...... to change significantly in the future with increasing electrification, energy efficiency (e.g. building insulation), and improved comfort (especially for cooling). Some extreme scenarios are presented here to quantify the potential impact of these changes on the electricity sector, with results revealing...... that the demand for electricity could double compared to today, depending on how these changes occur. Considering the scale of additional electricity required to electrify future heating and cooling demands, heat pumps should be prioritised over electric heating and other alternatives, such as district heating...

  2. Heat tolerance in wheat

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari

    climate, wheat is sensitive to heat stress. We need to understand how our crops will perform in these changing climatic conditions and how we can develop varieties, which are more tolerant. The PhD study focussed on understanding heat tolerance in wheat with a combined approach of plant physiology...... and quantitative genetics in particular, plant phenotyping based quantitative trait loci (QTL) discovery for a physiological trait under heat stress. Chlorophyll a fluorescence trait, Fv/Fm was used as a phenotyping tool, as it reflects the effect of heat stress on maximum photochemical efficiency of photosystem...... among cultivars due to heat stress as the GD of most of them remained similar in control and stress. The second study investigated if it was possible to use detached leaves to screen for heat tolerance instead of intact plants. The previously selected 41 cultivars, known to differ in v/Fm, were used...

  3. Counterflow Regolith Heat Exchanger

    Science.gov (United States)

    Zubrin, Robert; Jonscher, Peter

    2013-01-01

    A problem exists in reducing the total heating power required to extract oxygen from lunar regolith. All such processes require heating a great deal of soil, and the heat energy is wasted if it cannot be recycled from processed material back into new material. The counterflow regolith heat exchanger (CoRHE) is a device that transfers heat from hot regolith to cold regolith. The CoRHE is essentially a tube-in-tube heat exchanger with internal and external augers attached to the inner rotating tube to move the regolith. Hot regolith in the outer tube is moved in one direction by a right-hand - ed auger, and the cool regolith in the inner tube is moved in the opposite direction by a left-handed auger attached to the inside of the rotating tube. In this counterflow arrangement, a large fraction of the heat from the expended regolith is transferred to the new regolith. The spent regolith leaves the heat exchanger close to the temperature of the cold new regolith, and the new regolith is pre-heated close to the initial temperature of the spent regolith. Using the CoRHE can reduce the heating requirement of a lunar ISRU system by 80%, reducing the total power consumption by a factor of two. The unique feature of this system is that it allows for counterflow heat exchange to occur between solids, instead of liquids or gases, as is commonly done. In addition, in variants of this concept, the hydrogen reduction can be made to occur within the counterflow heat exchanger itself, enabling a simplified lunar ISRU (in situ resource utilization) system with excellent energy economy and continuous nonbatch mode operation.

  4. Laser Processed Heat Exchangers

    Science.gov (United States)

    Hansen, Scott

    2017-01-01

    The Laser Processed Heat Exchanger project will investigate the use of laser processed surfaces to reduce mass and volume in liquid/liquid heat exchangers as well as the replacement of the harmful and problematic coatings of the Condensing Heat Exchangers (CHX). For this project, two scale unit test articles will be designed, manufactured, and tested. These two units are a high efficiency liquid/liquid HX and a high reliability CHX.

  5. Heat transfer II essentials

    CERN Document Server

    REA, The Editors of

    1988-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Heat Transfer II reviews correlations for forced convection, free convection, heat exchangers, radiation heat transfer, and boiling and condensation.

  6. Advances in heat transfer

    CERN Document Server

    Hartnett, James P; Cho, Young I; Greene, George A

    2001-01-01

    Heat transfer is the exchange of heat energy between a system and its surrounding environment, which results from a temperature difference and takes place by means of a process of thermal conduction, mechanical convection, or electromagnetic radiation. Advances in Heat Transfer is designed to fill the information gap between regularly scheduled journals and university-level textbooks by providing in-depth review articles over a broader scope than is allowable in either journals or texts.

  7. Convection heat transfer

    CERN Document Server

    Bejan, Adrian

    2013-01-01

    Written by an internationally recognized authority on heat transfer and thermodynamics, this second edition of Convection Heat Transfer contains new and updated problems and examples reflecting real-world research and applications, including heat exchanger design. Teaching not only structure but also technique, the book begins with the simplest problem solving method (scale analysis), and moves on to progressively more advanced and exact methods (integral method, self similarity, asymptotic behavior). A solutions manual is available for all problems and exercises.

  8. Pump Assisted Heat Pipe

    OpenAIRE

    Miyazaki, Yoshiro; OSHIMA, Shigeto

    1987-01-01

    A labortory model of a pump assisted heat pipe has been fablicated and tested. An arterial heat pipe with axial grooves and a gear pump with a magnetic coupling have been developed for the model. The test has been carried out successfully. The reasonable thermal conductance has been obtained so far as the necessary working fluid flow rate is supplied. The necessary flow rate exceeds the theoretical one and the excess flow rate increases as the heat load increases.

  9. Hydride heat pump

    Science.gov (United States)

    Cottingham, James G.

    1977-01-01

    Method and apparatus for the use of hydrides to exhaust heat from one temperature source and deliver the thermal energy extracted for use at a higher temperature, thereby acting as a heat pump. For this purpose there are employed a pair of hydridable metal compounds having different characteristics working together in a closed pressure system employing a high temperature source to upgrade the heat supplied from a low temperature source.

  10. Introduction to Heat Pipes

    Science.gov (United States)

    Ku, Jentung

    2015-01-01

    This is the presentation file for the short course Introduction to Heat Pipes, to be conducted at the 2015 Thermal Fluids and Analysis Workshop, August 3-7, 2015, Silver Spring, Maryland. NCTS 21070-15. Course Description: This course will present operating principles of the heat pipe with emphases on the underlying physical processes and requirements of pressure and energy balance. Performance characterizations and design considerations of the heat pipe will be highlighted. Guidelines for thermal engineers in the selection of heat pipes as part of the spacecraft thermal control system, testing methodology, and analytical modeling will also be discussed.

  11. INNOVATIVE HEAT FLUX SENSOR

    Directory of Open Access Journals (Sweden)

    G. N. Lukyanov

    2017-02-01

    Full Text Available Subject of Study.We present a method for heat flux measuring with the use of polarization properties of ferroelectric ceramics. Heat flux innovative sensor is developed on the basis of the proposed method. Its experimental verification is carried out. Method. The measurements are based on maintaining a balance between the processes caused by thermal energy and the energy of the electric field in the ferroelectric ceramics. Main Results. The testing of the proposed heat flux sensor has been organized in two stages. At the first stage the primary calibration has been performed by calibrated sensors ITP MG4.03/x(y “Potok”. At the second stage the testing of heat flux sensor has been carried out for calculating the quantity of heat. The comparison of the results to the readings of serial heat meters VKT-7 and STK-15 has been performed. Experiments have shown that the polarization properties of the ferroelectric ceramics can be used to measure the heat flow. Practical Relevance. The proposed sensor can be recommended as an apartment-level heat meter. The calibration of the proposed heat flux sensor with more accurate measurement tools gives the possibility to include it on the State Register of Measuring Instruments.

  12. Mesoscopic photon heat transistor

    DEFF Research Database (Denmark)

    Ojanen, T.; Jauho, Antti-Pekka

    2008-01-01

    We show that the heat transport between two bodies, mediated by electromagnetic fluctuations, can be controlled with an intermediate quantum circuit-leading to the device concept of a mesoscopic photon heat transistor (MPHT). Our theoretical analysis is based on a novel Meir-Wingreen-Landauer-typ......We show that the heat transport between two bodies, mediated by electromagnetic fluctuations, can be controlled with an intermediate quantum circuit-leading to the device concept of a mesoscopic photon heat transistor (MPHT). Our theoretical analysis is based on a novel Meir...

  13. Microtube strip heat exchanger

    Science.gov (United States)

    Doty, F. D.

    1991-07-01

    During the last quarter, Doty Scientific, Inc. (DSI) continued to make progress on the microtube strip (MTS) heat exchanger. The DSI completed a heat exchanger stress analysis of the ten-module heat exchanger bank; and performed a shell-side flow inhomogeneity analysis of the three-module heat exchanger bank. The company produced 50 tubestrips using an in-house CNC milling machine and began pressing them onto tube arrays. The DSI revised some of the tooling required to encapsulate a tube array and press tubestrips into the array to improve some of the prototype tooling.

  14. Solar assisted heat pumps

    OpenAIRE

    Godbold, R; Paurine, A; Maidment, GG

    2016-01-01

    Solar Assisted Heat Pumps have the potential to provide low carbon heat for domestic hot water generation and low temperature heating. They have advantages over conventional solar thermal systems because they can generate heating and hot water during periods of low or zero solar, whist still maintain the advantage of not needing to be connected to the gas grid. They are simple in nature and can be installed in a wide range of applications. They are also currently uncommon in the UK so a thoro...

  15. Heated Tube Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Heated Tube Facility at NASA GRC investigates cooling issues by simulating conditions characteristic of rocket engine thrust chambers and high speed airbreathing...

  16. Quantum heat traces

    Science.gov (United States)

    Avramidi, Ivan G.

    2017-02-01

    We study new invariants of elliptic partial differential operators acting on sections of a vector bundle over a closed Riemannian manifold that we call the relativistic heat trace and the quantum heat traces. We obtain some reduction formulas expressing these new invariants in terms of some integral transforms of the usual classical heat trace and compute the asymptotics of these invariants. The coefficients of these asymptotic expansion are determined by the usual heat trace coefficients (which are locally computable) as well as by some new global invariants.

  17. Diversity and biology of heat-resistant fungi

    NARCIS (Netherlands)

    Houbraken, J.; Dijksterhuis, J.; Samson, R.A.; Wong, Hin-Chung

    2012-01-01

    Heat-resistant fungi survive high temperatures (75°C or more for at least 30 min). For food microbiology, these fungi are of interest because of spoilage of canned and pasteurized food products, and cause damage for millions of dollars in the fruit-juice and beverage branch. Many studies have been

  18. The small heat shock proteins family : The long forgotten chaperones

    NARCIS (Netherlands)

    Garrido, C.; Paul, C.; Seigneuric, R.; Kampinga, H. H.

    2012-01-01

    Small heat shock proteins are a rather heterogeneous family of ATP-independent chaperones, some of which have been proven to block protein aggregation and help the cells to survive stressful conditions. Although much less studied than high molecular weight HSPs like HSP70/HSPA or HSP90/HSPC, their

  19. Heat Pipe Integrated Microsystems

    Energy Technology Data Exchange (ETDEWEB)

    Gass, K.; Robertson, P.J.; Shul, R.; Tigges, C.

    1999-03-30

    The trend in commercial electronics packaging to deliver ever smaller component packaging has enabled the development of new highly integrated modules meeting the demands of the next generation nano satellites. At under ten kilograms, these nano satellites will require both a greater density electronics and a melding of satellite structure and function. Better techniques must be developed to remove the subsequent heat generated by the active components required to-meet future computing requirements. Integration of commercially available electronics must be achieved without the increased costs normally associated with current generation multi chip modules. In this paper we present a method of component integration that uses silicon heat pipe technology and advanced flexible laminate circuit board technology to achieve thermal control and satellite structure. The' electronics/heat pipe stack then becomes an integral component of the spacecraft structure. Thermal management on satellites has always been a problem. The shrinking size of electronics and voltage requirements and the accompanying reduction in power dissipation has helped the situation somewhat. Nevertheless, the demands for increased onboard processing power have resulted in an ever increasing power density within the satellite body. With the introduction of nano satellites, small satellites under ten kilograms and under 1000 cubic inches, the area available on which to place hot components for proper heat dissipation has dwindled dramatically. The resulting satellite has become nearly a solid mass of electronics with nowhere to dissipate heat to space. The silicon heat pipe is attached to an aluminum frame using a thermally conductive epoxy or solder preform. The frame serves three purposes. First, the aluminum frame provides a heat conduction path from the edge of the heat pipe to radiators on the surface of the satellite. Secondly, it serves as an attachment point for extended structures attached

  20. Lunar Base Heat Pump

    Science.gov (United States)

    Walker, D.; Fischbach, D.; Tetreault, R.

    1996-01-01

    The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

  1. Estimation of diver survival time in a lost bell

    Energy Technology Data Exchange (ETDEWEB)

    Tipton, M.J.; Franks, C. [Surrey Univ., Guildford (United Kingdom); Meneilly, G.S. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Medicine; Mekjavic, I.B. [Simon Fraser University, Vancouver (Canada). Dept. of Kinesiology

    1997-04-01

    Mathematical models of the human thermoregulatory system have been used to make predictions of the likely survival of divers in a ``lost bell`` who can be exposed to very low ambient temperatures. The circumstances considered are not the most extreme but those where, partly by shivering, the individual can re-enter thermal balance. The ability accurately to predict the level and duration of metabolic heat production is critical for the estimation of survival time under these conditions. Limitations on the accuracy of current models arise from the lack of precision in modelling the intensity and duration of the metabolic (shivering) response. A different basis for predicting shivering endurance using the time to hypogylcaemia (blood glucose level less than 2.5 mmol/1) is proposed. This leads to predicted survival times ranging from 10 to over 24 hours for those individuals able to stabilise deep body temperature. This seems to be more consistent with the limited experimental data which exists than the 8-9 hours predicted by other models. In order to help maintain blood sugar levels, and hence metabolic heat production, it is recommended that emergency rations within bells should provide 500g of carbohydrate a day. (59 figures; 221 references). (UK)

  2. Solar Heating System with Building-Integrated Heat Storage

    DEFF Research Database (Denmark)

    Heller, Alfred

    1996-01-01

    Traditional solar heating systems cover between 5 and 10% of the heat demand fordomestic hot water and comfort heating. By applying storage capacity this share can beincreased much. The Danish producer of solar heating systems, Aidt-Miljø, markets such a system including storage of dry sand heated...... by PP-pipe heat exchanger. Heat demand is reduced due to direct solar heating, and due to storage. Heat demand is reduced due to direct solar heating, due to storage and due to lower heat losses through the ground. In theory, by running the system flow backwards through the sand storage, active heating...... can be achieved.The objective of the report is to present results from measured system evaluation andcalculations and to give guidelines for the design of such solar heating systems with building integrated sand storage. The report is aimed to non-technicians. In another report R-006 the main results...

  3. Specific microRNAs Regulate Heat Stress Responses in Caenorhabditis elegans

    DEFF Research Database (Denmark)

    Nehammer, Camilla; Podolska, Agnieszka; Mackowiak, Sebastian D

    2015-01-01

    to heat stress in Caenorhabditis elegans and show that a discrete subset of miRNAs is thermoregulated. Using in-depth phenotypic analyses of miRNA deletion mutant strains we reveal multiple developmental and post-developmental survival and behavioral functions for specific miRNAs during heat stress. We...

  4. Survival Processing Eliminates Collaborative Inhibition.

    Science.gov (United States)

    Reysen, Matthew B; Bliss, Heather; Baker, Melissa A

    2017-04-11

    The present experiments examined the effect of processing words for their survival value, relevance to moving, and pleasantness on participants' free recall scores in both nominal groups (non-redundant pooled individual scores) and collaborative dyads. Overall, participants recalled more words in the survival processing conditions than in the moving and pleasantness processing conditions. Furthermore, nominal groups in both the pleasantness condition (Experiment 1) and the moving and pleasantness conditions (Experiment 2) recalled more words than collaborative groups, thereby replicating the oft-observed effect of collaborative inhibition. However, processing words for their survival value appeared to eliminate the deleterious effects of collaborative remembering in both Experiments 1 and 2. These results are discussed in the context of the retrieval strategy disruption hypothesis and the effects of both expertise and collaborative skill on group remembering.

  5. Heat pipes and use of heat pipes in furnace exhaust

    Science.gov (United States)

    Polcyn, Adam D.

    2010-12-28

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  6. Scraped surface heat exchangers.

    Science.gov (United States)

    Rao, Chetan S; Hartel, Richard W

    2006-01-01

    Scraped surface heat exchangers (SSHEs) are commonly used in the food, chemical, and pharmaceutical industries for heat transfer, crystallization, and other continuous processes. They are ideally suited for products that are viscous, sticky, that contain particulate matter, or that need some degree of crystallization. Since these characteristics describe a vast majority of processed foods, SSHEs are especially suited for pumpable food products. During operation, the product is brought in contact with a heat transfer surface that is rapidly and continuously scraped, thereby exposing the surface to the passage of untreated product. In addition to maintaining high and uniform heat exchange, the scraper blades also provide simultaneous mixing and agitation. Heat exchange for sticky and viscous foods such as heavy salad dressings, margarine, chocolate, peanut butter, fondant, ice cream, and shortenings is possible only by using SSHEs. High heat transfer coefficients are achieved because the boundary layer is continuously replaced by fresh material. Moreover, the product is in contact with the heating surface for only a few seconds and high temperature gradients can be used without the danger of causing undesirable reactions. SSHEs are versatile in the use of heat transfer medium and the various unit operations that can be carried out simultaneously. This article critically reviews the current understanding of the operations and applications of SSHEs.

  7. Electron heat flux instability

    Science.gov (United States)

    Saeed, Sundas; Sarfraz, M.; Yoon, P. H.; Lazar, M.; Qureshi, M. N. S.

    2017-02-01

    The heat flux instability is an electromagnetic mode excited by a relative drift between the protons and two-component core-halo electrons. The most prominent application may be in association with the solar wind where drifting electron velocity distributions are observed. The heat flux instability is somewhat analogous to the electrostatic Buneman or ion-acoustic instability driven by the net drift between the protons and bulk electrons, except that the heat flux instability operates in magnetized plasmas and possesses transverse electromagnetic polarization. The heat flux instability is also distinct from the electrostatic counterpart in that it requires two electron species with relative drifts with each other. In the literature, the heat flux instability is often called the 'whistler' heat flux instability, but it is actually polarized in the opposite sense to the whistler wave. This paper elucidates all of these fundamental plasma physical properties associated with the heat flux instability starting from a simple model, and gradually building up more complexity towards a solar wind-like distribution functions. It is found that the essential properties of the instability are already present in the cold counter-streaming electron model, and that the instability is absent if the protons are ignored. These instability characteristics are highly reminiscent of the electron firehose instability driven by excessive parallel temperature anisotropy, propagating in parallel direction with respect to the ambient magnetic field, except that the free energy source for the heat flux instability resides in the effective parallel pressure provided by the counter-streaming electrons.

  8. Basic Comfort Heating Principles.

    Science.gov (United States)

    Dempster, Chalmer T.

    The material in this beginning book for vocational students presents fundamental principles needed to understand the heating aspect of the sheet metal trade and supplies practical experience to the student so that he may become familiar with the process of determining heat loss for average structures. Six areas covered are: (1) Background…

  9. Passive Vaporizing Heat Sink

    Science.gov (United States)

    Knowles, TImothy R.; Ashford, Victor A.; Carpenter, Michael G.; Bier, Thomas M.

    2011-01-01

    A passive vaporizing heat sink has been developed as a relatively lightweight, compact alternative to related prior heat sinks based, variously, on evaporation of sprayed liquids or on sublimation of solids. This heat sink is designed for short-term dissipation of a large amount of heat and was originally intended for use in regulating the temperature of spacecraft equipment during launch or re-entry. It could also be useful in a terrestrial setting in which there is a requirement for a lightweight, compact means of short-term cooling. This heat sink includes a hermetic package closed with a pressure-relief valve and containing an expendable and rechargeable coolant liquid (e.g., water) and a conductive carbon-fiber wick. The vapor of the liquid escapes when the temperature exceeds the boiling point corresponding to the vapor pressure determined by the setting of the pressure-relief valve. The great advantage of this heat sink over a melting-paraffin or similar phase-change heat sink of equal capacity is that by virtue of the =10x greater latent heat of vaporization, a coolant-liquid volume equal to =1/10 of the paraffin volume can suffice.

  10. Microchannel heat sink assembly

    Science.gov (United States)

    Bonde, Wayne L.; Contolini, Robert J.

    1992-01-01

    The present invention provides a microchannel heat sink with a thermal range from cryogenic temperatures to several hundred degrees centigrade. The heat sink can be used with a variety of fluids, such as cryogenic or corrosive fluids, and can be operated at a high pressure. The heat sink comprises a microchannel layer preferably formed of silicon, and a manifold layer preferably formed of glass. The manifold layer comprises an inlet groove and outlet groove which define an inlet manifold and an outlet manifold. The inlet manifold delivers coolant to the inlet section of the microchannels, and the outlet manifold receives coolant from the outlet section of the microchannels. In one embodiment, the manifold layer comprises an inlet hole extending through the manifold layer to the inlet manifold, and an outlet hole extending through the manifold layer to the outlet manifold. Coolant is supplied to the heat sink through a conduit assembly connected to the heat sink. A resilient seal, such as a gasket or an O-ring, is disposed between the conduit and the hole in the heat sink in order to provide a watetight seal. In other embodiments, the conduit assembly may comprise a metal tube which is connected to the heat sink by a soft solder. In still other embodiments, the heat sink may comprise inlet and outlet nipples. The present invention has application in supercomputers, integrated circuits and other electronic devices, and is suitable for cooling materials to superconducting temperatures.

  11. Mechanisms of Coronal Heating

    Indian Academy of Sciences (India)

    The Sun is a mysterious star. The high temperature of the chromosphere and corona present one of the most puzzling problems of solar physics. Observations show that the solar coronal heating problem is highly complex with many different facts. It is likely that different heating mechanisms are at work in solar corona.

  12. Heat pump unit. Waermepumpenaggregat

    Energy Technology Data Exchange (ETDEWEB)

    Gail, J.

    1984-11-29

    An internal combustion engine with an integrated heat pump and an electricity generator are combined in one engine housing. The internal combustion engine consists of a working cylinder parallel to the drive shaft with a double piston arrangement for swashplate operation, where at least the back of one piston works as the compressor of a heat pump. (orig.).

  13. Combined Heat and Power

    Science.gov (United States)

    CHP is on-site electricity generation that captures the heat that would otherwise be wasted to provide useful thermal energy such as steam or hot water than can be used for space heating, cooling, domestic hot water and industrial processes.

  14. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Dr. Glenn Mitchell , Emergency physician at Mercy Health System in Chesterfield, Missouri Heat-related illness can be caused by overexposure to the sun or any situation that involves extreme heat. Young children and the elderly are most at risk, but anyone can be affected. ...

  15. Heat sterilization of wood

    Science.gov (United States)

    Xiping Wang

    2010-01-01

    Two important questions should be considered in heat sterilizing solid wood materials: First, what temperature–time regime is required to kill a particular pest? Second, how much time is required to heat the center of any wood configuration to the kill temperature? The entomology research on the first question has facilitated the development of international standards...

  16. Plumbing and Heating Curriculum.

    Science.gov (United States)

    EASTCONN Regional Educational Services Center, North Windham, CT.

    Theory and experience in the following areas are included in this plumbing curriculum: (1) plumbing fixtures and heating; (2) city water service; (3) fixture roughing; (4) venting; and (5) solar heating systems. The plumbing program manual includes the following sections: (1) general objectives for grades 10, 11, and 12; (2) a list of 33 major…

  17. Survival in Women with NSCLC

    Science.gov (United States)

    Katcoff, Hannah; Wenzlaff, Angela S.; Schwartz, Ann G.

    2014-01-01

    Introduction Although lung cancer is the leading cause of cancer death in women, few studies have investigated the hormonal influence on survival after a lung cancer diagnosis and results have been inconsistent. We evaluated the role of reproductive and hormonal factors in predicting overall survival in women with non–small-cell lung cancer (NSCLC). Methods Population-based lung cancer cases diagnosed between November 1, 2001 and October 31, 2005 were identified through the Metropolitan Detroit Surveillance, Epidemiology, and End Results Registry. Interview and follow-up data were collected for 485 women. Cox proportional hazard regression models were used to determine hazard ratios (HRs) for death after an NSCLC diagnosis associated with reproductive and hormonal variables. Results Use of hormone therapy (HT) was associated with improved survival (HR, 0.69; 95% confidence interval, 0.54–0.89), adjusting for stage, surgery, radiation, education level, pack-years of smoking, age at diagnosis, race, and a multiplicative interaction between stage and radiation. No other reproductive or hormonal factor was associated with survival after an NSCLC diagnosis. Increased duration of HT use before the lung cancer diagnosis (132 months or longer) was associated with improved survival (HR, 0.54; 95% confidence interval, 0.37–0.78), and this finding remained significant in women taking either estrogen alone or progesterone plus estrogen, never smokers, and smokers. Conclusion These findings suggest that HT use, in particular use of estrogen plus progesterone, and long-term HT use are associated with improved survival of NSCLC. PMID:24496005

  18. Survival of Sami cancer patients

    Directory of Open Access Journals (Sweden)

    Leena Soininen

    2012-07-01

    Full Text Available Objectives. The incidence of cancer among the indigenous Sami people of Northern Finland is lower than among the Finnish general population. The survival of Sami cancer patients is not known, and therefore it is the object of this study. Study design. The cohort consisted of 2,091 Sami and 4,161 non-Sami who lived on 31 December 1978 in the two Sami municipalities of Inari and Utsjoki, which are located in Northern Finland and are 300–500 km away from the nearest central hospital. The survival experience of Sami and non-Sami cancer patients diagnosed in this cohort during 1979–2009 was compared with that of the Finnish patients outside the cohort. Methods. The Sami and non-Sami cancer patients were matched to other Finnish cancer patients for gender, age and year of diagnosis and for the site of cancer. An additional matching was done for the stage at diagnosis. Cancer-specific survival analyses were made using the Kaplan–Meier method and Cox regression modelling. Results. There were 204 Sami and 391 non-Sami cancer cases in the cohort, 20,181 matched controls without matching with stage, and 7,874 stage-matched controls. In the cancer-specific analysis without stage variable, the hazard ratio for Sami was 1.05 (95% confidence interval 0.85–1.30 and for non-Sami 1.02 (0.86–1.20, indicating no difference between the survival of those groups and other patients in Finland. Likewise, when the same was done by also matching the stage, there was no difference in cancer survival. Conclusion. Long distances to medical care or Sami ethnicity have no influence on the cancer patient survival in Northern Finland.

  19. Survival following spinal cord infarction.

    Science.gov (United States)

    New, P W; McFarlane, C L

    2013-06-01

    Retrospective open cohort. To calculate the survival of patients with spinal cord infarction and to compare the cause of death in patients with different mechanisms of ischaemic injury. Spinal Rehabilitation Unit, Melbourne, Victoria, Australia. Consecutive admissions between 1 January 1995 and 31 December 2008 with recent onset of spinal cord infarction. Linkage to the Registry of Births, Deaths and Marriages (Victoria) was used to determine survival following discharge from in-patient rehabilitation and cause of death. A total of 44 patients were admitted (males=26, 59%), with a median age of 72 years (interquartile range (IQR) 62-79). One patient died during their in-patient rehabilitation programme. In all, 14 patients (n=14/44; 33%) died during the follow-up period. The median survival after diagnosis was 56 months (IQR 28-85) and after discharge from in-patient rehabilitation was 46 months (IQR 25-74). The 1- and 5-year mortality rates were 7.0% (n=3/43; 95% confidence interval (CI)=2.4-18.6%) and 20.9% (n=9/43; 95% CI=11.4-35.2%). There was no statistically significant difference in survival between patients with the different aetiologies of spinal cord infarction (other vs idiopathic: χ(2)=0.6, P=0.7; other vs vascular: χ(2)=1.9, P=0.3). There was no relationship between survival and gender (χ(2)=0.2, P=0.6), age (χ(2)=3.0, P=0.08), level of injury (χ(2)=0.0, P=1) or American Spinal Cord Society Impairment Scale grade of spinal cord injury (χ(2)=0.02, P=0.9). Patients with spinal cord infarction appear to have a fair survival after discharge from in-patient rehabilitation, not withstanding the occurrence of risk factors of vascular disease in many patients.

  20. Genetic aspects of piglet survival

    OpenAIRE

    Knol, E.F.

    2001-01-01

    Piglet mortality is high. In the USA nearly 20% of the piglets do not survive between late gestation and weaning; 7% of the piglets die during farrowing and some 13% are lost during lactation. These statistics from the USA are no exception to the norm. Selection for increased piglet survival, if possible, could have an important economic impact.

    Litters and sows

    Data on some 33.000 litters and some 400.000 piglets from a commercial breeding progr...

  1. Frailty Models in Survival Analysis

    CERN Document Server

    Wienke, Andreas

    2010-01-01

    The concept of frailty offers a convenient way to introduce unobserved heterogeneity and associations into models for survival data. In its simplest form, frailty is an unobserved random proportionality factor that modifies the hazard function of an individual or a group of related individuals. "Frailty Models in Survival Analysis" presents a comprehensive overview of the fundamental approaches in the area of frailty models. The book extensively explores how univariate frailty models can represent unobserved heterogeneity. It also emphasizes correlated frailty models as extensions of

  2. Improved solar heating systems

    Science.gov (United States)

    Schreyer, J.M.; Dorsey, G.F.

    1980-05-16

    An improved solar heating system is described in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75 to 180/sup 0/F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing ad releasing heat for distribution.

  3. Graphene heat dissipating structure

    Science.gov (United States)

    Washburn, Cody M.; Lambert, Timothy N.; Wheeler, David R.; Rodenbeck, Christopher T.; Railkar, Tarak A.

    2017-08-01

    Various technologies presented herein relate to forming one or more heat dissipating structures (e.g., heat spreaders and/or heat sinks) on a substrate, wherein the substrate forms part of an electronic component. The heat dissipating structures are formed from graphene, with advantage being taken of the high thermal conductivity of graphene. The graphene (e.g., in flake form) is attached to a diazonium molecule, and further, the diazonium molecule is utilized to attach the graphene to material forming the substrate. A surface of the substrate is treated to comprise oxide-containing regions and also oxide-free regions having underlying silicon exposed. The diazonium molecule attaches to the oxide-free regions, wherein the diazonium molecule bonds (e.g., covalently) to the exposed silicon. Attachment of the diazonium plus graphene molecule is optionally repeated to enable formation of a heat dissipating structure of a required height.

  4. Solar heating system

    Science.gov (United States)

    Schreyer, James M.; Dorsey, George F.

    1982-01-01

    An improved solar heating system in which the incident radiation of the sun is absorbed on collector panels, transferred to a storage unit and then distributed as heat for a building and the like. The improvement is obtained by utilizing a storage unit comprising separate compartments containing an array of materials having different melting points ranging from 75.degree. to 180.degree. F. The materials in the storage system are melted in accordance with the amount of heat absorbed from the sun and then transferred to the storage system. An efficient low volume storage system is provided by utilizing the latent heat of fusion of the materials as they change states in storing and releasing heat for distribution.

  5. Oscillating-Coolant Heat Exchanger

    Science.gov (United States)

    Scotti, Stephen J.; Blosser, Max L.; Camarda, Charles J.

    1992-01-01

    Devices useful in situations in which heat pipes inadequate. Conceptual oscillating-coolant heat exchanger (OCHEX) transports heat from its hotter portions to cooler portions. Heat transported by oscillation of single-phase fluid, called primary coolant, in coolant passages. No time-averaged flow in tubes, so either heat removed from end reservoirs on every cycle or heat removed indirectly by cooling sides of channels with another coolant. Devices include leading-edge cooling devices in hypersonic aircraft and "frost-free" heat exchangers. Also used in any situation in which heat pipe used and in other situations in which heat pipes not usable.

  6. School Leadership: Handbook for Survival.

    Science.gov (United States)

    Smith, Stuart C., Ed.; And Others

    Based on the assumption that the survival of the nation's schools and their leaders depends on these leaders having real influence over the quality of schooling, this volume draws from the work of many authorities to look at leadership from three perspectives: the person, the structure, and the skills. Chapters focusing on the person who holds the…

  7. Long-term haemodialysis survival

    DEFF Research Database (Denmark)

    Heaf, James; Nielsen, Arne Høj; Hansen, Henrik Post

    2012-01-01

    Haemodialysis (HD) treatment for end-stage renal disease bears a poor prognosis. We present a case of a patient who, apart from two transplant periods lasting 8 months in all, was treated with conventional in-centre HD three times a week and who survived for 41 years. Patients should be aware tha...

  8. Characteristics of Patients Who Survived

    NARCIS (Netherlands)

    Verlaan, Jorrit-Jan; Choi, David; Versteeg, Anne; Albert, Todd; Arts, Mark; Balabaud, Laurent; Bunger, Cody; Buchowski, Jacob Maciej; Chung, Chung Kee; Coppes, Maarten Hubert; Crockard, Hugh Alan; Depreitere, Bart; Fehlings, Michael George; Harrop, James; Kawahara, Norio; Kim, Eun Sang; Lee, Chong-Suh; Leung, Yee; Liu, Zhongjun; Martin-Benlloch, Antonio; Massicotte, Eric Maurice; Mazel, Christian; Meyer, Bernhard; Peul, Wilco; Quraishi, Nasir A.; Tokuhashi, Yasuaki; Tomita, Katsuro; Ulbricht, Christian; Wang, Michael; Oner, F. Cumhur

    2016-01-01

    Purpose Survival after metastatic cancer has improved at the cost of increased presentation with metastatic spinal disease. For patients with pathologic spinal fractures and/or spinal cord compression, surgical intervention may relieve pain and improve quality of life. Surgery is generally

  9. Genetic aspects of piglet survival

    NARCIS (Netherlands)

    Knol, E.F.

    2001-01-01

    Piglet mortality is high. In the USA nearly 20% of the piglets do not survive between late gestation and weaning; 7% of the piglets die during farrowing and some 13% are lost during lactation. These statistics from the USA are no exception to the norm. Selection for increased piglet

  10. Cool echidnas survive the fire

    Science.gov (United States)

    Nowack, Julia; Cooper, Christine Elizabeth; Geiser, Fritz

    2016-01-01

    Fires have occurred throughout history, including those associated with the meteoroid impact at the Cretaceous–Palaeogene (K–Pg) boundary that eliminated many vertebrate species. To evaluate the recent hypothesis that the survival of the K–Pg fires by ancestral mammals was dependent on their ability to use energy-conserving torpor, we studied body temperature fluctuations and activity of an egg-laying mammal, the echidna (Tachyglossus aculeatus), often considered to be a ‘living fossil’, before, during and after a prescribed burn. All but one study animal survived the fire in the prescribed burn area and echidnas remained inactive during the day(s) following the fire and substantially reduced body temperature during bouts of torpor. For weeks after the fire, all individuals remained in their original territories and compensated for changes in their habitat with a decrease in mean body temperature and activity. Our data suggest that heterothermy enables mammals to outlast the conditions during and after a fire by reducing energy expenditure, permitting periods of extended inactivity. Therefore, torpor facilitates survival in a fire-scorched landscape and consequently may have been of functional significance for mammalian survival at the K–Pg boundary. PMID:27075255

  11. Modelling survival and connectivity of

    NARCIS (Netherlands)

    van der Molen, J.; van Beek, J.; Augustine, S.; Vansteenbrugge, L.; van Walraven, L.; van Langenberg, V.; van der Veer, H.W.; Hostens, K.; Pitois, S.; Robbens, J.

    2015-01-01

    Three different models were applied to study the reproduction, survival and dispersal of Mnemiopsis leidyi in the Scheldt estuaries and the southern North Sea: a high-resolution particle tracking model with passive particles, a low-resolution particle tracking model with a reproduction model

  12. Survivability of SCADA Control Loop

    NARCIS (Netherlands)

    Camacho, José; de Boer, Pieter-Tjerk; Remke, Anne Katharina Ingrid

    2009-01-01

    The endorsement of information technologies for critical infrastructures control introduces new threats in their security and surveillance. Along with certain level of protection against attacks, it is desirable for critical processes to survive even if they succeed. A stochastic Petri Nets-based

  13. Paste heat exchange

    Energy Technology Data Exchange (ETDEWEB)

    1943-07-30

    The subject of coal paste heat exchangers is discussed in this letter report from Gelsenberg A.G. to I.G. Farbenindustrie A.G. Gelsenberg had given little consideration to the heating of coal paste by means of regeneration (heat exchange) because of the lack of experience in paste regeneration with bituminous coal, especially at 700 atmospheres. At the I.G. Farben plant at Poelitz, paste regeneration was carried out so that low concentration coal paste was heated in the regenerator together with the process gas, and the remaining coal was fed into the cold pass of the preheater in a thicker paste. Later tests proved this process viable. Gelsenberg heated normal coal paste and the gas in heat exchangers with the goal of relieving the preheater. Good results were achieved without change in design. The coal paste was heated with process gas in the regenerator at up to 315 degrees with constant pressure difference, so that after three months no decrease in K-values and no deposition or thickening was observed. Through the omission of paste gas, the pressure difference of the system became more constant and did not rise above the former level. The temperature also was more controllable, the chamber smoother running. Principal thermal data are given in a table. 1 table, 1 graph.

  14. Pioneering Heat Pump Project

    Energy Technology Data Exchange (ETDEWEB)

    Aschliman, Dave [Indiana Inst. of Technology, Inc., Fort Wayne, IN (United States); Lubbehusen, Mike [Indiana Inst. of Technology, Inc., Fort Wayne, IN (United States)

    2015-06-30

    This project was initiated at a time when ground coupled heat pump systems in this region were limited in size and quantity. There were economic pressures with costs for natural gas and electric utilities that had many organizations considering ground coupled heat pumps; The research has added to the understanding of how ground temperatures fluctuate seasonally and how this affects the performance and operation of the heat pumps. This was done by using a series of temperature sensors buried within the middle of one of the vertical bore fields with sensors located at various depths below grade. Trending of the data showed that there is a lag in ground temperature with respect to air temperatures in the shoulder months, however as full cooling and heating season arrives, the heat rejection and heat extraction from the ground has a significant effect on the ground temps; Additionally it is better understood that while a large community geothermal bore field serving multiple buildings does provide a convenient central plant to use, it introduces complexity of not being able to easily model and predict how each building will contribute to the loads in real time. Additional controllers and programming were added to provide more insight into this real time load profile and allow for intelligent shedding of load via a dry cooler during cool nights in lieu of rejecting to the ground loop. This serves as a means to ‘condition’ the ground loop and mitigate thermal creep of the field, as is typically observed; and It has been observed when compared to traditional heating and cooling equipment, there is still a cost premium to use ground source heat pumps that is driven mostly by the cost for vertical bore holes. Horizontal loop systems are less costly to install, but do not perform as well in this climate zone for heating mode

  15. An analytical dynamic model of heat transfer from the heating body to the heated room

    Directory of Open Access Journals (Sweden)

    Mižáková Jana

    2017-01-01

    Full Text Available On the base of mathematical description of thermal balance the dynamic model of the hot-water heating body (radiator was designed. The radiator is mathematically described as a heat transfer system between heating water and warmed-up air layer. Similarly, the dynamic model of heat transfer through the wall from the heated space to the outdoor environment was design. Both models were interconnected into dynamic model of heat transfer from the heating body to the heated room and they will be implemented into simulation model of the heating system in Matlab/Simulink environment.

  16. Transient heat conduction in a heat fin

    Science.gov (United States)

    Brody, Jed; Brown, Max

    2017-08-01

    We immerse the bottom of a rod in ice water and record the time-dependent temperatures at positions along the length of the rod. Though the experiment is simple, a surprisingly difficult problem in heat conduction must be solved to obtain a theoretical fit to the measured data. The required equipment is very inexpensive and could be assigned as a homework exercise or a hands-on component of an online course.

  17. Elementary heat transfer analysis

    CERN Document Server

    Whitaker, Stephen; Hartnett, James P

    1976-01-01

    Elementary Heat Transfer Analysis provides information pertinent to the fundamental aspects of the nature of transient heat conduction. This book presents a thorough understanding of the thermal energy equation and its application to boundary layer flows and confined and unconfined turbulent flows. Organized into nine chapters, this book begins with an overview of the use of heat transfer coefficients in formulating the flux condition at phase interface. This text then explains the specification as well as application of flux boundary conditions. Other chapters consider a derivation of the tra

  18. Heat exchanger design handbook

    CERN Document Server

    Thulukkanam, Kuppan

    2013-01-01

    Completely revised and updated to reflect current advances in heat exchanger technology, Heat Exchanger Design Handbook, Second Edition includes enhanced figures and thermal effectiveness charts, tables, new chapter, and additional topics--all while keeping the qualities that made the first edition a centerpiece of information for practicing engineers, research, engineers, academicians, designers, and manufacturers involved in heat exchange between two or more fluids.See What's New in the Second Edition: Updated information on pressure vessel codes, manufacturer's association standards A new c

  19. Heat pump planning handbook

    CERN Document Server

    Bonin, Jürgen

    2015-01-01

    The Heat Pump Planning Handbook contains practical information and guidance on the design, planning and selection of heat pump systems, allowing engineers, designers, architects and construction specialists to compare a number of different systems and options. Including detailed descriptions of components and their functions and reflecting the current state of technology this guide contains sample tasks and solutions as well as new model calculations and planning evaluations. Also economic factors and alternative energy sources are covered, which are essential at a time of rising heat costs. T

  20. Ventilation with heat recovery

    DEFF Research Database (Denmark)

    Tommerup, Henrik M.; Svendsen, Svend

    2005-01-01

    This paper presents the experiences from the use of ventilation with heat recovery in several experimental single-family houses developed and built within the last four years to meet the new Danish energy requirements of 2005. Included are descriptions of the ventilation system components...... and the main functional demands as well as measurements of the thermal efficiency, electricity consumptions and building air tightness. The paper addresses the aspects of minimizing the heat loss from the duct system and the heat recovery unit (when placed in an unheated attic space) in order to obtain...

  1. Heat treatment furnace

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. [Clothing and heat disorder].

    Science.gov (United States)

    Satsumoto, Yayoi

    2012-06-01

    The influence of the clothing material properties(like water absorbency and rapid dryness, water vapor absorption, water vapor permeability and air permeability) and the design factor of the clothing(like opening condition and fitting of clothing), which contributed to prevent heat disorder, was outlined. WBGT(wet-bulb globe temperature) is used to show a guideline for environmental limitation of activities to prevent heat disorder. As the safety function is more important than thermal comfort for some sportswear and protective clothing with high cover area, clothing itself increases the risk of heat disorder. WBGT is corrected by CAF (clothing adjustment factor) in wearing such kind of protective clothing.

  3. Molecular heat pump.

    Science.gov (United States)

    Segal, Dvira; Nitzan, Abraham

    2006-02-01

    We propose a molecular device that pumps heat against a thermal gradient. The system consists of a molecular element connecting two thermal reservoirs that are characterized by different spectral properties. The pumping action is achieved by applying an external force that periodically modulates molecular levels. This modulation affects periodic oscillations of the internal temperature of the molecule and the strength of its coupling to each reservoir resulting in a net heat flow in the desired direction. The heat flow is examined in the slow and fast modulation limits and for different modulation wave forms, thus making it possible to optimize the device performance.

  4. Design of serially connected district heating heat pumps utilising a geothermal heat source

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2017-01-01

    The design of two heat pumps (HP), connected in series, was investigated for operation in the district heating (DH) network of the Greater Copenhagen area, Denmark. The installation was dimensioned to supply 7.2 MW of heat at a temperature of 85 °C. The heat pumps utilise a geothermal heat source...

  5. Counterflow Regolith Heat Exchanger Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The counterflow regolith heat exchanger (CoRHE) is a device that transfers heat from hot regolith to cold regolith. The CoRHE is essentially a tube-in-tube heat...

  6. Ideas and perspectives: Heat stress: more than hot air

    Science.gov (United States)

    De Boeck, Hans J.; Van De Velde, Helena; De Groote, Toon; Nijs, Ivan

    2016-10-01

    Climate models project an important increase in the frequency and intensity of heat waves. In gauging the impact on plant responses, much of the focus has been on air temperatures, while a critical analysis of leaf temperatures during heat extremes has not been conducted. Nevertheless, direct physiological consequences from heat depend primarily on leaf rather than on air temperatures. We discuss how the interplay between various environmental variables and the plants' stomatal response affects leaf temperatures and the potential for heat stress by making use of both an energy balance model and field data. The results demonstrate that this interplay between plants and environment can cause leaf temperature to vary substantially at the same air temperature. In general, leaves tended to heat up when radiation was high and when stomates were closed, as expected. But perhaps counterintuitively, high air humidity also raised leaf temperatures, while humid conditions are typically regarded as benign with respect to plant survival since they limit water loss. High wind speeds brought the leaf temperature closer to the air temperature, which can imply either cooling or warming (i.e. abating or reinforcing heat stress) depending on other prevailing conditions. The results thus indicate that heat waves characterized by similar extreme air temperatures may pose little danger under some atmospheric conditions but could be lethal in other cases. The trends illustrated here should give ecologists and agronomists a more informed indication about which circumstances are most conducive to the occurrence of heat stress.

  7. Metabolic and hormonal acclimation to heat stress in domesticated ruminants.

    Science.gov (United States)

    Bernabucci, U; Lacetera, N; Baumgard, L H; Rhoads, R P; Ronchi, B; Nardone, A

    2010-07-01

    Environmentally induced periods of heat stress decrease productivity with devastating economic consequences to global animal agriculture. Heat stress can be defined as a physiological condition when the core body temperature of a given species exceeds its range specified for normal activity, which results from a total heat load (internal production and environment) exceeding the capacity for heat dissipation and this prompts physiological and behavioral responses to reduce the strain. The ability of ruminants to regulate body temperature is species- and breed-dependent. Dairy breeds are typically more sensitive to heat stress than meat breeds, and higher-producing animals are more susceptible to heat stress because they generate more metabolic heat. During heat stress, ruminants, like other homeothermic animals, increase avenues of heat loss and reduce heat production in an attempt to maintain euthermia. The immediate responses to heat load are increased respiration rates, decreased feed intake and increased water intake. Acclimatization is a process by which animals adapt to environmental conditions and engage behavioral, hormonal and metabolic changes that are characteristics of either acclimatory homeostasis or homeorhetic mechanisms used by the animals to survive in a new 'physiological state'. For example, alterations in the hormonal profile are mainly characterized by a decline and increase in anabolic and catabolic hormones, respectively. The response to heat load and the heat-induced change in homeorhetic modifiers alters post-absorptive energy, lipid and protein metabolism, impairs liver function, causes oxidative stress, jeopardizes the immune response and decreases reproductive performance. These physiological modifications alter nutrient partitioning and may prevent heat-stressed lactating cows from recruiting glucose-sparing mechanisms (despite the reduced nutrient intake). This might explain, in large part, why decreased feed intake only accounts for

  8. Microplate Heat Exchanger Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a microplate heat exchanger for cryogenic cooling systems used for continuous flow distributed cooling systems, large focal plane arrays, multiple cooling...

  9. Radiative heat transfer

    CERN Document Server

    Modest, Michael F

    2013-01-01

    The third edition of Radiative Heat Transfer describes the basic physics of radiation heat transfer. The book provides models, methodologies, and calculations essential in solving research problems in a variety of industries, including solar and nuclear energy, nanotechnology, biomedical, and environmental. Every chapter of Radiative Heat Transfer offers uncluttered nomenclature, numerous worked examples, and a large number of problems-many based on real world situations-making it ideal for classroom use as well as for self-study. The book's 24 chapters cover the four major areas in the field: surface properties; surface transport; properties of participating media; and transfer through participating media. Within each chapter, all analytical methods are developed in substantial detail, and a number of examples show how the developed relations may be applied to practical problems. It is an extensive solution manual for adopting instructors. Features: most complete text in the field of radiative heat transfer;...

  10. Heat Exhaustion and Heatstroke

    Science.gov (United States)

    ... of salt contribute to heat-related illnesses. Some sports drinks can help replenish the salt in your body ... temperature.Drink fluids, such as water or a sports drink. Do not guzzle them, but take sips. Do ...

  11. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Health System in Chesterfield, Missouri Heat-related illness can be caused by overexposure to the sun or ... the elderly are most at risk, but anyone can be affected. Here you will find information about ...

  12. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... weak pulse; rapid, shallow breathing; vomiting; and increased body temperature of more than 104 degrees. People with ... nausea, loss of consciousness, vomiting or a high body temperature. For late stage heat stroke symptoms, cool ...

  13. 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.

  14. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Care Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat- ... CPR if the person becomes unconscious. READ IN EMERGENCIES A-Z Stroke Chest Pain Is ALWAYS A ...

  15. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Care Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat- ... CPR if the person becomes unconscious. READ IN EMERGENCIES A-Z Your Blood Pressure Score is as ...

  16. Heat and mass transfer

    CERN Document Server

    Karwa, Rajendra

    2017-01-01

    This textbook presents the classical treatment of the problems of heat transfer in an exhaustive manner with due emphasis on understanding of the physics of the problems. This emphasis is especially visible in the chapters on convective heat transfer. Emphasis is laid on the solution of steady and unsteady two-dimensional heat conduction problems. Another special feature of the book is a chapter on introduction to design of heat exchangers and their illustrative design problems. A simple and understandable treatment of gaseous radiation has been presented. A special chapter on flat plate solar air heater has been incorporated that covers thermo-hydraulic modeling and simulation. The chapter on mass transfer has been written looking specifically at the needs of the students of mechanical engineering. The book includes a large number and variety of solved problems with supporting line diagrams. The author has avoided duplicating similar problems, while incorporating more application-based examples. All the end-...

  17. Policies for Renewable Heat

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    This paper builds on IEA publications, Deploying Renewables, Principles for Effective Policies and Deploying Renewables, Best and Future Policy Practice, that discuss the 'integrated policy approach,' whereby renewable energy technologies require different support policies at different stages of their maturity pathways. The paper discusses how the integrated policy approach applies to renewable heat. It attempts to provide guidance for policy-makers on renewable heat throughout the different phases of the policy lifecycle, allowing for the specific challenges of renewable heat and needs of the many stakeholders involved. Stimulating a market for heat involves challenges that are different and, often, more difficult to overcome than in the electricity and transport sectors.

  18. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Care Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat- ... CPR if the person becomes unconscious. READ IN EMERGENCIES A-Z Sprains and Strains Head Injury Seizures ...

  19. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... pulse; rapid, shallow breathing; vomiting; and increased body temperature of more than 104 degrees. People with these ... loss of consciousness, vomiting or a high body temperature. For late stage heat stroke symptoms, cool the ...

  20. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Care Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat- ... CPR if the person becomes unconscious. READ IN EMERGENCIES A-Z Bites and Stings Listen to your ...

  1. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Medicine's Front Line Observation Emergency Care Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share ... Illnesses Dr. Glenn Mitchell , Emergency physician at Mercy Health System in Chesterfield, Missouri Heat-related illness can ...

  2. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... skin; headache; dizziness; weakness; feeling exhausted; heavy sweating; nausea; and giddiness. Symptoms of heat stroke (late stage ... skin, rapid pulse, elevated or lowered blood pressure, nausea, loss of consciousness, vomiting or a high body ...

  3. Heat Island Compendium

    Science.gov (United States)

    Heat islands can be mitigated through measures like planting trees and vegetation, installing green roofs and cool roofs, and using cool pavements. The compendium describes all of these strategies and shows how communities around the country are being used

  4. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... ICE” in Your Cell Phone Prepare for Disasters Communication With Your Family And Your Doctor About Your ... Dr. Glenn Mitchell , Emergency physician at Mercy Health System in Chesterfield, Missouri Heat-related illness can be ...

  5. Heat tolerance in wheat

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari

    genetic determination (GD). An initial mass screening of 1,274 wheat cultivars (diverse origin) showed a GD of 8.5%. A stronger heat treatment was given in the second screening with 138 selected cultivars resulting in larger differentiation of cultivars (GD 15.4%). The GD further increased to 27....../Fm and dry matter accumulation during heat stress is a step forward to document that phenotypic differences measured by phenomic approaches can be translated into overall plant performance under heat stress. The fourth study focussed on associating phenotypic variations identified by Fv/Fm to genetic......As a consequence of global climate change, heat stress together with other abiotic stresses will remain an important determinant of future food security. Wheat (Triticum aestivum L.) is the third most important crop of the world feeding one third of the world population. Being a crop of temperate...

  6. Analytical heat transfer

    CERN Document Server

    Han, Je-Chin

    2012-01-01

    … it will complete my library … [and] complement the existing literature on heat transfer. It will be of value for both graduate students and faculty members.-Bengt Sunden, Lund University, Sweden

  7. Chiral Brownian heat pump

    OpenAIRE

    van den Broek, Martijn; Van den Broeck, Christian

    2008-01-01

    We present the exact analysis of a chiral Brownian motor and heat pump. Optimization of the construction predicts, for a nanoscale device, frequencies of the order of kHz and cooling rates of the order of femtojoule per second.

  8. Chiral brownian heat pump.

    Science.gov (United States)

    van den Broek, M; Van den Broeck, C

    2008-04-04

    We present the exact analysis of a chiral Brownian motor and heat pump. Optimization of the construction predicts, for a nanoscale device, frequencies of the order of kHz and cooling rates of the order of femtojoule per second.

  9. Chiral Brownian heat pump

    OpenAIRE

    Broek, M. van den; Broeck, C. Van Den

    2007-01-01

    We present the exact analysis of a chiral Brownian motor and heat pump. Optimization of the construction predicts, for a nanoscale device, frequencies of the order of kHz and cooling rates of the order of femtojoule per second.

  10. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... stage of heat illness) include flushed, hot, dry skin; fainting; a rapid, weak pulse; rapid, shallow breathing; vomiting; and increased body temperature of more than 104 degrees. People with these ...

  11. HEAT EXCHANGERS IN SEWAGE PIPES

    OpenAIRE

    Podobeková, Veronika; Peráčková, Jana

    2014-01-01

    The article discusses utilization of heat from waste water in sewage. During the year, temperature of water in sewage ranges between 10 °C and 20 °C and the heat from sewage could be used for heating, cooling and hot water preparation in building. The heat is extracted through a transfer surface area of the heat exchanger into the heat pump, which is able to utilize the low–potential energy. Different design and types of the heat exchangers in sewage are dealt with: heat exchangers embedded i...

  12. Improved Thin, Flexible Heat Pipes

    Science.gov (United States)

    Rosenfeld, John H.; Gernert, Nelson J.; Sarraf, David B.; Wollen, Peter J.; Surina, Frank C.; Fale, John E.

    2004-01-01

    Flexible heat pipes of an improved type are fabricated as layers of different materials laminated together into vacuum- tight sheets or tapes. In comparison with prior flexible heat pipes, these flexible heat pipes are less susceptible to leakage. Other advantages of these flexible heat pipes, relative to prior flexible heat pipes, include high reliability and greater ease and lower cost of fabrication. Because these heat pipes are very thin, they are highly flexible. When coated on outside surfaces with adhesives, these flexible heat pipes can be applied, like common adhesive tapes, to the surfaces of heat sinks and objects to be cooled, even if those surfaces are curved.

  13. Molecular heat pump

    OpenAIRE

    Segal, Dvira; Nitzan, Abraham

    2005-01-01

    We propose a novel molecular device that pumps heat against a thermal gradient. The system consists of a molecular element connecting two thermal reservoirs that are characterized by different spectral properties. The pumping action is achieved by applying an external force that periodically modulates molecular levels. This modulation affects periodic oscillations of the internal temperature of the molecule and the strength of its coupling to each reservoir resulting in a net heat flow in the...

  14. Thermal radiation heat transfer

    CERN Document Server

    Howell, John R; Siegel, Robert

    2016-01-01

    Further expanding on the changes made to the fifth edition, Thermal Radiation Heat Transfer, 6th Edition continues to highlight the relevance of thermal radiative transfer and focus on concepts that develop the radiative transfer equation (RTE). The book explains the fundamentals of radiative transfer, introduces the energy and radiative transfer equations, covers a variety of approaches used to gauge radiative heat exchange between different surfaces and structures, and provides solution techniques for solving the RTE.

  15. Individual social capital and survival

    DEFF Research Database (Denmark)

    Ejlskov, Linda; Mortensen, Rikke N; Overgaard, Charlotte

    2014-01-01

    BACKGROUND: The concept of social capital has received increasing attention as a determinant of population survival, but its significance is uncertain. We examined the importance of social capital on survival in a population study while focusing on gender differences. METHODS: We used data from...... a Danish regional health survey with a five-year follow-up period, 2007-2012 (n = 9288, 53.5% men, 46.5% women). We investigated the association between social capital and all-cause mortality, performing separate analyses on a composite measure as well as four specific dimensions of social capital while...... controlling for covariates. Analyses were performed with Cox proportional hazard models by which hazard ratios and 95% confidence intervals were calculated. RESULTS: For women, higher levels of social capital were associated with lower all-cause mortality regardless of age, socioeconomic status, health...

  16. Campylobacter virulence and survival factors.

    Science.gov (United States)

    Bolton, Declan J

    2015-06-01

    Despite over 30 years of research, campylobacteriosis is the most prevalent foodborne bacterial infection in many countries including in the European Union and the United States of America. However, relatively little is known about the virulence factors in Campylobacter or how an apparently fragile organism can survive in the food chain, often with enhanced pathogenicity. This review collates information on the virulence and survival determinants including motility, chemotaxis, adhesion, invasion, multidrug resistance, bile resistance and stress response factors. It discusses their function in transition through the food processing environment and human infection. In doing so it provides a fundamental understanding of Campylobacter, critical for improved diagnosis, surveillance and control. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Does Intelligence Provide Survival Value?

    OpenAIRE

    Cairns, John

    2009-01-01

    Intelligence is defined as a general mental capacity to reason, plan, solve problems, think abstractly, comprehend ideas, and learn. Intelligence can also be defined as the ability to acquire and apply information gathered from the environment to modify its behavior. It is this intelligence that has allowed the genus Homo to survive for 2 million years. However, recently the global financial meltdown and the deleterious effects of climate change raise the question of whether intelligence has ...

  18. Survival on Land and Sea

    Science.gov (United States)

    1943-01-01

    flower, leaf steams, and young leaves may be eaten cooked as greens provided you cook them in several changes of water to remove the bitter taste and...and become a weed almost throughout the tropics. Its bladdery pods contain a single retl tomato-like fruit that is edible. Raspberries, blackberries ...plant that 108 SURVIVAL OK LAND AND SEA is about one foot In height and has blue flowers and inflated leaf stems. The young leaves, leafy stalks

  19. Columbia Crew Survival Investigation Report

    Science.gov (United States)

    2009-01-01

    NASA commissioned the Columbia Accident Investigation Board (CAIB) to conduct a thorough review of both the technical and the organizational causes of the loss of the Space Shuttle Columbia and her crew on February 1, 2003. The accident investigation that followed determined that a large piece of insulating foam from Columbia s external tank (ET) had come off during ascent and struck the leading edge of the left wing, causing critical damage. The damage was undetected during the mission. The CAIB's findings and recommendations were published in 2003 and are available on the web at http://caib.nasa.gov/. NASA responded to the CAIB findings and recommendations with the Space Shuttle Return to Flight Implementation Plan. Significant enhancements were made to NASA's organizational structure, technical rigor, and understanding of the flight environment. The ET was redesigned to reduce foam shedding and eliminate critical debris. In 2005, NASA succeeded in returning the space shuttle to flight. In 2010, the space shuttle will complete its mission of assembling the International Space Station and will be retired to make way for the next generation of human space flight vehicles: the Constellation Program. The Space Shuttle Program recognized the importance of capturing the lessons learned from the loss of Columbia and her crew to benefit future human exploration, particularly future vehicle design. The program commissioned the Spacecraft Crew Survival Integrated Investigation Team (SCSIIT). The SCSIIT was asked to perform a comprehensive analysis of the accident, focusing on factors and events affecting crew survival, and to develop recommendations for improving crew survival for all future human space flight vehicles. To do this, the SCSIIT investigated all elements of crew survival, including the design features, equipment, training, and procedures intended to protect the crew. This report documents the SCSIIT findings, conclusions, and recommendations.

  20. Statistical analysis of survival data.

    Science.gov (United States)

    Crowley, J; Breslow, N

    1984-01-01

    A general review of the statistical techniques that the authors feel are most important in the analysis of survival data is presented. The emphasis is on the study of the duration of time between any two events as applied to people and on the nonparametric and semiparametric models most often used in these settings. The unifying concept is the hazard function, variously known as the risk, the force of mortality, or the force of transition.

  1. LATERAL SURVIVAL: AN OT ACCOUNT

    Directory of Open Access Journals (Sweden)

    Moira Yip

    2004-12-01

    Full Text Available When laterals are the targets of phonological processes, laterality may or may not survive. In a fixed feature geometry, [lateral] should be lost if its superordinate node is eliminated by either the spreading of a neighbouring node, or by coda neutralization. So if [lateral] is under Coronal (Blevins 1994, it should be lost under Place assimilation, and if [lateral] is under Sonorant Voicing (Rice & Avery 1991 it should be lost by rules that spread voicing. Yet in some languages lateral survives such spreading intact. Facts like these argue against a universal attachment of [lateral] under either Coronal or Sonorant Voicing, and in favour of an account in terms of markedness constraints on feature-co-occurrence (Padgett 2000. The core of an OT account is that IFIDENTLAT is ranked above whatever causes neutralization, such as SHARE-F or *CODAF. laterality will survive. If these rankings are reversed, we derive languages in which laterality is lost. The other significant factor is markedness. High-ranked feature co-occurrence constraints like *LATDORSAL can block spreading from affecting laterals at all.

  2. Heat exchanger device and method for heat removal or transfer

    Science.gov (United States)

    Koplow, Jeffrey P

    2013-12-10

    Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

  3. Latent heat sink in soil heat flux measurements

    Science.gov (United States)

    The surface energy balance includes a term for soil heat flux. Soil heat flux is difficult to measure because it includes conduction and convection heat transfer processes. Accurate representation of soil heat flux is an important consideration in many modeling and measurement applications. Yet, the...

  4. Ground Source Heat Pump in Heating System with Electronics Monitoring

    Directory of Open Access Journals (Sweden)

    NEAMŢU Ovidiu

    2013-10-01

    Full Text Available The monitoring system is implemented for a ground coupled heat pump in heating/ system. The borehole heat exchangers – which are 150 m long - are filled with a mixture of water and ethilene glycol calledbrine. Metering and monitoring energy consumption is achieved for: heat pump, circulation pumps, additional electrical heating, hot air ventilation systems, control systems with sensors: analog and smart sensors. Instantaneous values are stored in a local computer.

  5. A REVIEW ON HEAT TRANSFER THROUGH HELICAL COIL HEAT EXCHANGERS

    OpenAIRE

    Surendra Vishvakarma*, Sanjay Kumbhare, K. K. Thakur

    2016-01-01

    This study presents a brief review of heat transfer through helical coil heat exchangers. Helical coils of circular cross section have been used in wide variety of applications due to simplicity in manufacturing. Enhancement in heat transfer due to helical coils has been reported by many researchers. While the heat transfer characteristics of double pipe helical heat exchangers are available in the literature, there exists no published experimental or theoretical analysis of a helically coile...

  6. Moist Heat or Dry Heat for Delayed Onset Muscle Soreness

    OpenAIRE

    Petrofsky, Jerrold; Berk, Lee; Bains, Gurinder; Khowailed, Iman Akef; Hui, Timothy; Granado, Michael; Laymon, Mike; Lee, Haneul

    2013-01-01

    Background Heat is commonly used in physical therapy following exercise induced delayed onset muscle soreness (DOMS). Most heat modalities used in a clinical setting for DOMS are only applied for 5 to 20 minutes. This minimal heat exposure causes little, if any, change in deep tissue temperature. For this reason, long duration dry chemical heat packs are used at home to slowly and safely warm tissue and reduce potential heat damage while reducing pain associated from DOMS. Clinically, it has ...

  7. Fault-Tolerant Heat Exchanger

    Science.gov (United States)

    Izenson, Michael G.; Crowley, Christopher J.

    2005-01-01

    A compact, lightweight heat exchanger has been designed to be fault-tolerant in the sense that a single-point leak would not cause mixing of heat-transfer fluids. This particular heat exchanger is intended to be part of the temperature-regulation system for habitable modules of the International Space Station and to function with water and ammonia as the heat-transfer fluids. The basic fault-tolerant design is adaptable to other heat-transfer fluids and heat exchangers for applications in which mixing of heat-transfer fluids would pose toxic, explosive, or other hazards: Examples could include fuel/air heat exchangers for thermal management on aircraft, process heat exchangers in the cryogenic industry, and heat exchangers used in chemical processing. The reason this heat exchanger can tolerate a single-point leak is that the heat-transfer fluids are everywhere separated by a vented volume and at least two seals. The combination of fault tolerance, compactness, and light weight is implemented in a unique heat-exchanger core configuration: Each fluid passage is entirely surrounded by a vented region bridged by solid structures through which heat is conducted between the fluids. Precise, proprietary fabrication techniques make it possible to manufacture the vented regions and heat-conducting structures with very small dimensions to obtain a very large coefficient of heat transfer between the two fluids. A large heat-transfer coefficient favors compact design by making it possible to use a relatively small core for a given heat-transfer rate. Calculations and experiments have shown that in most respects, the fault-tolerant heat exchanger can be expected to equal or exceed the performance of the non-fault-tolerant heat exchanger that it is intended to supplant (see table). The only significant disadvantages are a slight weight penalty and a small decrease in the mass-specific heat transfer.

  8. Liquid/liquid heat exchanger

    Science.gov (United States)

    Miller, C. G.

    1980-01-01

    Conceptual design for heat exchanger, utilizing two immiscible liquids with dissimilar specific gravities in direct contact, is more efficient mechanism of heat transfer than conventional heat exchangers with walls or membranes. Concept could be adapted for collection of heat from solar or geothermal sources.

  9. Heat Sink Design and Optimization

    Science.gov (United States)

    2015-12-01

    HEAT SINK DESIGN AND OPTIMIZATION I...REPORT DATE (DD-MM-YYYY) December 2015 2. REPORT TYPE Final 3. DATES COVERED (From – To) 4. TITLE AND SUBTITLE HEAT SINK DESIGN AND OPTIMIZATION...distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Heat sinks are devices that are used to enhance heat dissipation

  10. Structures to radiate heat softly

    Energy Technology Data Exchange (ETDEWEB)

    Perilae, T.; Wikstroem, T. [ed.

    1997-11-01

    Over the past fifty years, heating systems in single-family houses have taken a great leap forward. First wood-burning stoves gave way to oil heaters; then these were superseded by central heating systems; and now conventional central heating systems have lost their way with the increasingly widespread use of room-specific heating systems

  11. Experiments Demonstrate Geothermal Heating Process

    Science.gov (United States)

    Roman, Harry T.

    2012-01-01

    When engineers design heat-pump-based geothermal heating systems for homes and other buildings, they can use coil loops buried around the perimeter of the structure to gather low-grade heat from the earth. As an alternative approach, they can drill well casings and store the summer's heat deep in the earth, then bring it back in the winter to warm…

  12. Kajian Eksperimen Heat Exchahger Pada Heat Pump Menggunakan Refrijeran Hidrokarbon

    Directory of Open Access Journals (Sweden)

    Kusnandar

    2016-03-01

    Full Text Available Heat pump or usually known as pump energy is a device that can cooling and heating to be used, which functions as a cooling evaporator can be direct replace to heating as a function of the condenser using a reversing valve.. Using heat exchangers in the heat pump system is installed on the suction line and discharge line, so it will give the suction line temperature changes will be higher and discharge line temperatures will be lower, resulting in a greater cooling effect and lighter work of compression. The heat pump uses refrigerant type of hydrocarbon that is friendly to the environment, such as refrigerant R-290. From the results obtained research that the highest of Coefficient of Performance (COP in the heat pump using heat exchangers is 4.8 and without using heat exchanger is 4.1. So value of COP of haet pump between using heat exchanger and withaout heat exchanger is 0.7. The highest efficiency obtained on the heat pump using heat exchangers is 90.3%, and efficiency of heat pump without using heat exchanger is 78.95%.

  13. Heat-pipe planets

    Science.gov (United States)

    Moore, William B.; Simon, Justin I.; Webb, A. Alexander G.

    2017-09-01

    Observations of the surfaces of all terrestrial bodies other than Earth reveal remarkable but unexplained similarities: endogenic resurfacing is dominated by plains-forming volcanism with few identifiable centers, magma compositions are highly magnesian (mafic to ultra-mafic), tectonic structures are dominantly contractional, and ancient topographic and gravity anomalies are preserved to the present. Here we show that cooling via volcanic heat pipes may explain these observations and provide a universal model of the way terrestrial bodies transition from a magma-ocean state into subsequent single-plate, stagnant-lid convection or plate tectonic phases. In the heat-pipe cooling mode, magma moves from a high melt-fraction asthenosphere through the lithosphere to erupt and cool at the surface via narrow channels. Despite high surface heat flow, the rapid volcanic resurfacing produces a thick, cold, and strong lithosphere which undergoes contractional strain forced by downward advection of the surface toward smaller radii. We hypothesize that heat-pipe cooling is the last significant endogenic resurfacing process experienced by most terrestrial bodies in the solar system, because subsequent stagnant-lid convection produces only weak tectonic deformation. Terrestrial exoplanets appreciably larger than Earth may remain in heat-pipe mode for much of the lifespan of a Sun-like star.

  14. High-Performance Heat Pipe

    Science.gov (United States)

    Alario, J. P.; Kosson, R.; Haslett, R.

    1985-01-01

    Single vapor channel and single liquid channel joined by axial slot. New design, permits high heat-transport capacity without excessively reducing heat-transfer efficiency. Contains two large axial channels, one for vapor and one for liquid, permitting axial transport and radial heat-transfer requirements met independently. Heat pipe has capacity of approximately 10 to sixth power watt-inches (2.5 X 10 to sixth power watt-cm) orders of magnitude greater than heat capacity of existing heat pipes. Design has high radial-heat-transfer efficiency, structurally simple, and has large liquid and vapor areas.

  15. Multileg Heat-Pipe Evaporator

    Science.gov (United States)

    Alario, J. P.; Haslett, R. A.

    1986-01-01

    Parallel pipes provide high heat flow from small heat exchanger. Six parallel heat pipes extract heat from overlying heat exchanger, forming evaporator. Vapor channel in pipe contains wick that extends into screen tube in liquid channel. Rods in each channel hold wick and screen tube in place. Evaporator compact rather than extended and more compatible with existing heat-exchanger geometries. Prototype six-pipe evaporator only 0.3 m wide and 0.71 m long. With ammonia as working fluid, transports heat to finned condenser at rate of 1,200 W.

  16. Intensification of Convective Heat Transfer in Heating Device of Mobile Heating System with BH-Heat Generator

    Directory of Open Access Journals (Sweden)

    N. A. Nesenchuk

    2013-01-01

    Full Text Available Directions pertaining to intensification of convective heat transfer in a soft heating device have been experimentally investigated  in the paper and the most efficient one has been selected that is creation of artificial roughness on the device surface. The considered heating device for a heat supply system of a mobile object has been made of soft polymer material (polyvinyl chloride. Following  evaluation results of  heat exchange intensification a criteria equation has been obtained for calculation of external heat transfer with due account of heat transfer intensification.

  17. Stage at diagnosis and ovarian cancer survival

    DEFF Research Database (Denmark)

    Maringe, Camille; Walters, Sarah; Butler, John

    2012-01-01

    We investigate what role stage at diagnosis bears in international differences in ovarian cancer survival.......We investigate what role stage at diagnosis bears in international differences in ovarian cancer survival....

  18. Formula study for plate heat exchanger in the central heating regulation of the indirect connection hot water heating system

    National Research Council Canada - National Science Library

    Minghui CUI; Dezhi MENG; Chengming NI

    2016-01-01

    Plate heat exchanger has unique advantages and becomes dominant heat exchange equipment in heating engineering, but there is no heating regulation formula of plate exchanger applied in central heating...

  19. Microgravity condensing heat exchanger

    Science.gov (United States)

    Thomas, Christopher M. (Inventor); Ma, Yonghui (Inventor); North, Andrew (Inventor); Weislogel, Mark M. (Inventor)

    2011-01-01

    A heat exchanger having a plurality of heat exchanging aluminum fins with hydrophilic condensing surfaces which are stacked and clamped between two cold plates. The cold plates are aligned radially along a plane extending through the axis of a cylindrical duct and hold the stacked and clamped portions of the heat exchanging fins along the axis of the cylindrical duct. The fins extend outwardly from the clamped portions along approximately radial planes. The spacing between fins is symmetric about the cold plates, and are somewhat more closely spaced as the angle they make with the cold plates approaches 90.degree.. Passageways extend through the fins between vertex spaces which provide capillary storage and communicate with passageways formed in the stacked and clamped portions of the fins, which communicate with water drains connected to a pump externally to the duct. Water with no entrained air is drawn from the capillary spaces.

  20. Elements of heat transfer

    CERN Document Server

    Rathakrishnan, Ethirajan

    2012-01-01

    1 Basic Concepts and Definitions1.1 Introduction1.1.1 Driving Potential1.2 Dimensions and Units1.2.1 Dimensional Homogeneity1.3 Closed and Open Systems1.3.1 Closed System (ControlMass)1.3.2 Isolated System1.3.3 Open System (ControlVolume)1.4 Forms of Energy1.4.1 Internal Energy1.5 Properties of a System1.5.1 Intensive and Extensive Properties1.6 State and Equilibrium1.7 Thermal and Calorical Properties1.7.1 Specific Heat of an Incompressible Substance1.7.2 Thermally Perfect Gas 1.8 The Perfect Gas1.9 Summary1.10 Exercise ProblemsConduction Heat Transfer2.1 Introduction2.2 Conduction Heat Trans

  1. Large Scale Solar Heating

    DEFF Research Database (Denmark)

    Heller, Alfred

    2001-01-01

    The main objective of the research was to evaluate large-scale solar heating connected to district heating (CSDHP), to build up a simulation tool and to demonstrate the application of the simulation tool for design studies and on a local energy planning case. The evaluation was mainly carried out......). Simulation programs are proposed as control supporting tool for daily operation and performance prediction of central solar heating plants. Finaly the CSHP technolgy is put into persepctive with respect to alternatives and a short discussion on the barries and breakthrough of the technology are given....... model is designed and validated on the Marstal case. Applying the Danish Reference Year, a design tool is presented. The simulation tool is used for proposals for application of alternative designs, including high-performance solar collector types (trough solar collectors, vaccum pipe collectors...

  2. Thermal radiation heat transfer

    CERN Document Server

    Howell, John R; Mengüç, M Pinar

    2011-01-01

    Providing a comprehensive overview of the radiative behavior and properties of materials, the fifth edition of this classic textbook describes the physics of radiative heat transfer, development of relevant analysis methods, and associated mathematical and numerical techniques. Retaining the salient features and fundamental coverage that have made it popular, Thermal Radiation Heat Transfer, Fifth Edition has been carefully streamlined to omit superfluous material, yet enhanced to update information with extensive references. Includes four new chapters on Inverse Methods, Electromagnetic Theory, Scattering and Absorption by Particles, and Near-Field Radiative Transfer Keeping pace with significant developments, this book begins by addressing the radiative properties of blackbody and opaque materials, and how they are predicted using electromagnetic theory and obtained through measurements. It discusses radiative exchange in enclosures without any radiating medium between the surfaces-and where heat conduction...

  3. Heat and mass transfer

    CERN Document Server

    Baehr, Hans Dieter

    2011-01-01

    This comprehensive textbook provides a solid foundation of knowledge on the principles of heat and mass transfer and shows how to solve problems by applying modern methods. The basic theory is developed systematically, exploring in detail the solution methods to all important problems.   The thoroughly revised 3rd edition includes an introduction to the numerical solution of Finite Elements. A new section on heat and mass transfer in porous media has also been added.   The book will be useful not only to upper-level and graduate students, but also to practicing scientists and engineers, offering a firm understanding of the principles of heat and mass transfer, and showing how to solve problems by applying modern methods. Many completed examples and numerous exercises with solutions facilitate learning and understanding, and an appendix includes data on key properties of important substances.

  4. RF Pulsed Heating

    Energy Technology Data Exchange (ETDEWEB)

    Pritzkau, David P.

    2002-01-03

    RF pulsed heating is a process by which a metal is heated from magnetic fields on its surface due to high-power pulsed RF. When the thermal stresses induced are larger than the elastic limit, microcracks and surface roughening will occur due to cyclic fatigue. Pulsed heating limits the maximum magnetic field on the surface and through it the maximum achievable accelerating gradient in a normal conducting accelerator structure. An experiment using circularly cylindrical cavities operating in the TE{sub 011} mode at a resonant frequency of 11.424 GHz is designed to study pulsed heating on OFE copper, a material commonly used in normal conducting accelerator structures. The high-power pulsed RF is supplied by an X-band klystron capable of outputting 50 MW, 1.5 {micro}s pulses. The test pieces of the cavity are designed to be removable to allow testing of different materials with different surface preparations. A diagnostic tool is developed to measure the temperature rise in the cavity utilizing the dynamic Q change of the resonant mode due to heating. The diagnostic consists of simultaneously exciting a TE{sub 012} mode to steady-state in the cavity at 18 GHz and measuring the change in reflected power as the cavity is heated from high-power pulsed RF. Two experimental runs were completed. One run was executed at a calculated temperature rise of 120 K for 56 x 10{sup 6} pulses. The second run was executed at a calculated temperature rise of 82 K for 86 x 10{sup 6} pulses. Scanning electron microscope pictures show extensive damage occurring in the region of maximum temperature rise on the surface of the test pieces.

  5. Irreversible Brownian Heat Engine

    Science.gov (United States)

    Taye, Mesfin Asfaw

    2017-10-01

    We model a Brownian heat engine as a Brownian particle that hops in a periodic ratchet potential where the ratchet potential is coupled with a linearly decreasing background temperature. We show that the efficiency of such Brownian heat engine approaches the efficiency of endoreversible engine η =1-√{{Tc/Th}} [23]. On the other hand, the maximum power efficiency of the engine approaches η ^{MAX}=1-({Tc/Th})^{1\\over 4}. It is shown that the optimized efficiency always lies between the efficiency at quasistatic limit and the efficiency at maximum power while the efficiency at maximum power is always less than the optimized efficiency since the fast motion of the particle comes at the expense of the energy cost. If the heat exchange at the boundary of the heat baths is included, we show that such a Brownian heat engine has a higher performance when acting as a refrigerator than when operating as a device subjected to a piecewise constant temperature. The role of time on the performance of the motor is also explored via numerical simulations. Our numerical results depict that the time t and the external load dictate the direction of the particle velocity. Moreover, the performance of the heat engine improves with time. At large t (steady state), the velocity, the efficiency and the coefficient of performance of the refrigerator attain their maximum value. Furthermore, we study the effect of temperature by considering a viscous friction that decreases exponentially as the background temperature increases. Our result depicts that the Brownian particle exhibits a fast unidirectional motion when the viscous friction is temperature dependent than that of constant viscous friction. Moreover, the efficiency of this motor is considerably enhanced when the viscous friction is temperature dependent. On the hand, the motor exhibits a higher performance of the refrigerator when the viscous friction is taken to be constant.

  6. Starvation-Survival in Haloarchaea

    Science.gov (United States)

    Winters, Yaicha D.; Lowenstein, Tim K.; Timofeeff, Michael N.

    2015-01-01

    Recent studies claiming to revive ancient microorganisms trapped in fluid inclusions in halite have warranted an investigation of long-term microbial persistence. While starvation-survival is widely reported for bacteria, it is less well known for halophilic archaea—microorganisms likely to be trapped in ancient salt crystals. To better understand microbial survival in fluid inclusions in ancient evaporites, laboratory experiments were designed to simulate growth of halophilic archaea under media-rich conditions, complete nutrient deprivation, and a controlled substrate condition (glycerol-rich) and record their responses. Haloarchaea used for this work included Hbt. salinarum and isolate DV582A-1 (genus Haloterrigena) sub-cultured from 34 kyear Death Valley salt. Hbt. salinarum and DV582A-1 reacted to nutrient limitation with morphological and population changes. Starved populations increased and most cells converted from rods to small cocci within 56 days of nutrient deprivation. The exact timing of starvation adaptations and the physical transformations differed between species, populations of the same species, and cells of the same population. This is the first study to report the timing of starvation strategies for Hbt. salinarum and DV582A-1. The morphological states in these experiments may allow differentiation between cells trapped with adequate nutrients (represented here by early stages in nutrient-rich media) from cells trapped without nutrients (represented here by experimental starvation) in ancient salt. The hypothesis that glycerol, leaked from Dunaliella, provides nutrients for the survival of haloarchaea trapped in fluid inclusions in ancient halite, is also tested. Hbt. salinarum and DV582A-1 were exposed to a mixture of lysed and intact Dunaliella for 56 days. The ability of these organisms to utilize glycerol from Dunaliella cells was assessed by documenting population growth, cell length, and cell morphology. Hbt. salinarum and DV582A-1

  7. Starvation-Survival in Haloarchaea

    Directory of Open Access Journals (Sweden)

    Yaicha D. Winters

    2015-11-01

    Full Text Available Recent studies claiming to revive ancient microorganisms trapped in fluid inclusions in halite have warranted an investigation of long-term microbial persistence. While starvation-survival is widely reported for bacteria, it is less well known for halophilic archaea—microorganisms likely to be trapped in ancient salt crystals. To better understand microbial survival in fluid inclusions in ancient evaporites, laboratory experiments were designed to simulate growth of halophilic archaea under media-rich conditions, complete nutrient deprivation, and a controlled substrate condition (glycerol-rich and record their responses. Haloarchaea used for this work included Hbt. salinarum and isolate DV582A-1 (genus Haloterrigena sub-cultured from 34 kyear Death Valley salt. Hbt. salinarum and DV582A-1 reacted to nutrient limitation with morphological and population changes. Starved populations increased and most cells converted from rods to small cocci within 56 days of nutrient deprivation. The exact timing of starvation adaptations and the physical transformations differed between species, populations of the same species, and cells of the same population. This is the first study to report the timing of starvation strategies for Hbt. salinarum and DV582A-1. The morphological states in these experiments may allow differentiation between cells trapped with adequate nutrients (represented here by early stages in nutrient-rich media from cells trapped without nutrients (represented here by experimental starvation in ancient salt. The hypothesis that glycerol, leaked from Dunaliella, provides nutrients for the survival of haloarchaea trapped in fluid inclusions in ancient halite, is also tested. Hbt. salinarum and DV582A-1 were exposed to a mixture of lysed and intact Dunaliella for 56 days. The ability of these organisms to utilize glycerol from Dunaliella cells was assessed by documenting population growth, cell length, and cell morphology. Hbt. salinarum

  8. Survival of adult martens in Northern Wisconsin

    Science.gov (United States)

    Nicholas P. McCann; Patrick A. Zollner; Jonathan H. Gilbert

    2010-01-01

    Low adult marten (Martes americana) survival may be one factor limiting their population growth >30 yr after their reintroduction in Wisconsin, USA. We estimated annual adult marten survival at 0.81 in northern Wisconsin, with lower survival during winter (0.87) than summer-fall (1.00). Fisher (Martes pennanti) and raptor kills...

  9. Long-term survival after perforated diverticulitis

    NARCIS (Netherlands)

    J. Vermeulen (Jan); M.P. Gosselink (Martijn Pieter); W.C.J. Hop (Wim); E. van der Harst (Erwin); B.E. Hansen (Bettina); G.H.H. Mannaerts (Guido); P-P. Coene (Peter Paul); W.F. Weidema (Wibo); J.F. Lange (Johan)

    2011-01-01

    textabstractAim: Short-term survival after emergency surgery for perforated diverticulitis is poor. Less is known about long-term survival. The aims of this study were to evaluate long-term survival after discharge from hospital and to identify factors associated with prognosis. Method: All patients

  10. Clustered survival data with left-truncation

    DEFF Research Database (Denmark)

    Eriksson, Frank; Martinussen, Torben; Scheike, Thomas H.

    2015-01-01

    Left-truncation occurs frequently in survival studies, and it is well known how to deal with this for univariate survival times. However, there are few results on how to estimate dependence parameters and regression effects in semiparametric models for clustered survival data with delayed entry...

  11. 46 CFR 133.105 - Survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Survival craft. 133.105 Section 133.105 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS LIFESAVING SYSTEMS Requirements for All OSVs § 133.105 Survival craft. (a) Each survival craft must be approved and equipped as...

  12. 46 CFR 199.201 - Survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft. 199.201 Section 199.201 Shipping COAST... SYSTEMS FOR CERTAIN INSPECTED VESSELS Additional Requirements for Passenger Vessels § 199.201 Survival craft. (a) Each survival craft must be approved and equipped as follows: (1) Each lifeboat must be...

  13. 46 CFR 199.261 - Survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Survival craft. 199.261 Section 199.261 Shipping COAST... SYSTEMS FOR CERTAIN INSPECTED VESSELS Additional Requirements for Cargo Vessels § 199.261 Survival craft. (a) Each survival craft must be approved and equipped as follows: (1) Each lifeboat must be a totally...

  14. 46 CFR 28.120 - Survival craft.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Survival craft. 28.120 Section 28.120 Shipping COAST... VESSELS Requirements for All Vessels § 28.120 Survival craft. (a) Except as provided in paragraphs (b) through (h) of this section and 28.305, each vessel must carry the survival craft specified in Table 28...

  15. 46 CFR 174.320 - Damage survival.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Damage survival. 174.320 Section 174.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO... survival. A hopper dredge survives assumed damage if it meets the following conditions: (a) The maximum...

  16. Surviving the crash: T-cell homeostasis

    Indian Academy of Sciences (India)

    TOSHIBA

    Spatial and temporal elements. – Cellular sites for the integration of cell death and survival cues. – Spatial regulation of Notch activity for cell survival. Page 4. Cell survival is determined by the availability and uptake of nutrients live dead. Activated T-cells. T-cells. Page 5. dead wildtype. Bax active -6A7. Nucleus – H33342.

  17. Heat exchanger panel

    Science.gov (United States)

    Warburton, Robert E. (Inventor); Cuva, William J. (Inventor)

    2005-01-01

    The present invention relates to a heat exchanger panel which has broad utility in high temperature environments. The heat exchanger panel has a first panel, a second panel, and at least one fluid containment device positioned intermediate the first and second panels. At least one of the first panel and the second panel have at least one feature on an interior surface to accommodate the at least one fluid containment device. In a preferred embodiment, each of the first and second panels is formed from a high conductivity, high temperature composite material. Also, in a preferred embodiment, the first and second panels are joined together by one or more composite fasteners.

  18. Heat treatment deformations

    Energy Technology Data Exchange (ETDEWEB)

    Bavaro, A. (Soliveri SpA, Caravaggio (Italy))

    1990-02-01

    Types and causes of heat treatement derived isotropic and anisotropic dilatancies in ferrous materials are reviewed. The concepts are developed in such a way as to allow extension to all materials exhibiting martensitic tempering behaviour. This paper intends to illustrate the basic processes of dimensional variations undergone by the materials under heat treatments. The parametric analysis includes an analysis of the interactions amongst the parameters themselves. The relative importance of each parameter is assessed in order to determine methods to attenuate deformation action. Simplified examples are offered to provide technicians explanations as to why specific deformations occur and indications on improved materials working techniques.

  19. An oil heating method

    Energy Technology Data Exchange (ETDEWEB)

    Marinin, N.S.; Alpatov, G.K.; Glovatskiy, Ye.A.; Plyusnin, D.V.; Zhuravlev, V.S.

    1979-05-30

    The goal of the invention is to ensure complete utilization of the fuel combustion heat in simplification of a method for heating oil in a pipeline and to reduce the expenditures of its implementation. This goal is achieved by the fact that in the known method, which provides for the action on the oil being transported of high temperature, the oil is degassified inside the pipe in the pipeline sector, an oxidant (air) is supplied into the gas isolation zone and the obtained mixture is ignited.

  20. A heat transfer textbook

    CERN Document Server

    Lienhard, John H

    2011-01-01

    This introduction to heat transfer offers advanced undergraduate and graduate engineering students a solid foundation in the subjects of conduction, convection, radiation, and phase-change, in addition to the related topic of mass transfer. A staple of engineering courses around the world for more than three decades, it has been revised and updated regularly by the authors, a pair of recognized experts in the field. The text addresses the implications, limitations, and meanings of many aspects of heat transfer, connecting the subject to its real-world applications and developing students' ins

  1. Harnessing solar heat

    CERN Document Server

    Norton, Brian

    2013-01-01

    Systems engineered by man to harness solar heat in a controlled manner now include a diverse range of technologies each serving distinctive needs in particular climate contexts. This text covers the breadth of solar energy technologies for the conversion of solar energy to provide heat, either as the directly-used output or as an intermediary to other uses such as power generation or cooling. It is a wholly updated, extended and revised version of “Solar Energy Thermal Technology” first published in 1992. The text draws on the own author’s research and that of numerous colleagues and

  2. Solar industrial process heat

    Energy Technology Data Exchange (ETDEWEB)

    Lumsdaine, E.

    1981-04-01

    The aim of the assessment reported is to candidly examine the contribution that solar industrial process heat (SIPH) is realistically able to make in the near and long-term energy futures of the United States. The performance history of government and privately funded SIPH demonstration programs, 15 of which are briefly summarized, and the present status of SIPH technology are discussed. The technical and performance characteristics of solar industrial process heat plants and equipment are reviewed, as well as evaluating how the operating experience of over a dozen SIPH demonstration projects is influencing institutional acceptance and economoc projections. Implications for domestic energy policy and international implications are briefly discussed. (LEW)

  3. Carbon dioxide makes heat therapy work

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, H.

    1987-01-01

    Scientists can now propagate healthy blueberry and raspberry plants from virus-infected stock by treating it with heat and carbon dioxide. Plants are grown at 100/sup 0/F, which makes them develop faster than the virus can spread. Then cuttings are taken of the new growth - less than an inch long - and grown into full-sized, virus-free plants. But in this race to outdistance the virus, some plant species are not able to take the heat. Some even die. Chemical reactions double for every 14/sup 0/F rise in temperature. So, if you try to grow a plant at 100/sup 0/F that was originally growing at 86/sup 0/F, it will double its respiration rate. Adding carbon dioxide increases the rate of photosynthesis in plants, which increases the plant's food reserves. What carbon dioxide does to allow some plants to grow at temperatures at which they would otherwise not survive and it allows other plants to grow for longer periods at 100/sup 0/F. One problem with the process, says Converse, is that the longer plants are exposed to heat the greater the mutation rate. So, resulting clones should be closely examined for trueness to horticultural type.

  4. Influence on Heat Transfer Coefficient of Heat Exchanger by Velocity and Heat Transfer Temperature Difference

    Directory of Open Access Journals (Sweden)

    WANG Fang

    2017-04-01

    Full Text Available Aimed to insufficient heat transfer of heat exchanger, research the influence on the heat transfer coefficient impacted by velocity and heat transfer temperature difference of tube heat exchanger. According to the different heat transfer temperature difference and gas velocity,the experimental data were divided into group. Using the control variable method,the above two factors were analyzed separately. K一△T and k一:fitting curve were clone to obtain empirical function. The entire heat exchanger is as the study object,using numerical simulation methods,porous media,k一£model,second order upwind mode,and pressure一velocity coupling with SIMPLE algorithm,the entire heat exchanger temperature field and the heat transfer coefficient distribution were given. Finally the trend of the heat transfer coefficient effected by the above two factors was gotten.

  5. Passive Stability on an Entry Vehicle to Enhance Crew Survival

    Science.gov (United States)

    Deger, Daniel J.; Hoffman, David; Crull, Tim; Cuthbert, Peter; Liama, Eduardo; Madsen, Chris; Stuart, Phil; Bryant, Lee

    2005-01-01

    The most desirable crew survival feature for an entry vehicle is probably a full coverage escape system. With full coverage escape, crew survival is maintained for a wide range of failures by the allowing the crew to escape from the failed vehicle and performing the entry to touchdown flight phase in an alternative system. However, there are considerable challenges in providing a separate entry capability, and for some programs, requiring full coverage escape could result in program cancellation. An alternative means of providing for crew survival if the flight control system fails is to design a return vehicle that can enter without active attitude control. A study was performed to assess the feasibility of performing a totally passive entry. Lift over drag has a major impact on performing a passive entry, so a parametric of three typical lift over drag concepts was performed. First an assessment of historical entry vehicles was completed. Second an assessment of end of mission entry trajectories and entry trajectories initiated from ascent abort profiles were made. Trajectories for a wide array of pitch, yaw, and roll rates were made. Third, six-degree-of freedom analyses of the entry were performed. FOP a truly passive return, the entry vehicle must trim in only the heat shield forward orientation. An assessment of the effect of center of gravity placement to achieve this orientation was made.

  6. Conjugate heat and mass transfer in heat mass exchanger ducts

    CERN Document Server

    Zhang, Li-Zhi

    2013-01-01

    Conjugate Heat and Mass Transfer in Heat Mass Exchanger Ducts bridges the gap between fundamentals and recent discoveries, making it a valuable tool for anyone looking to expand their knowledge of heat exchangers. The first book on the market to cover conjugate heat and mass transfer in heat exchangers, author Li-Zhi Zhang goes beyond the basics to cover recent advancements in equipment for energy use and environmental control (such as heat and moisture recovery ventilators, hollow fiber membrane modules for humidification/dehumidification, membrane modules for air purification, desi

  7. Foreign Ownership and Long-term Survival

    DEFF Research Database (Denmark)

    Kronborg, Dorte; Thomsen, Steen

    2006-01-01

    Does foreign ownership enhance or decrease a firm's chances of survival? Over the 100 year period 1895-2001 this paper compares the survival of foreign subsidiaries in Denmark to a control sample matched by industry and firm size. We find that foreign-owned companies have higher survival...... probability. On average exit risk for domestic companies is 2.3 times higher than for foreign companies. First movers like Siemens, Philips, Kodak, Ford, GM or Goodyear have been active in the country for almost a century. Relative foreign survival increases with company age. However, the foreign survival...

  8. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Vomiting and Diarrhea Stroke Your Blood Pressure ...

  9. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Puncture Wounds Snake Bites Teeth (Dental Emergencies) ...

  10. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Bites and Stings Listen to your Symptoms - ...

  11. Nanocrystallinity induced by heating

    DEFF Research Database (Denmark)

    Mørup, Steen; Meaz, T.M.; Bender Koch, C.

    1997-01-01

    Samples of akaganeite (beta-FeOOH) and goethite (alpha-FeOOH) have been studied after heating at various temperatures up to 800 C. X-ray diffraction and Mossbauer spectroscopy measurements showed that slightly below the temperatures at which the samples transform to hematite (alpha-Fe2O3...

  12. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Sore Throat Suicide Your Blood Pressure Score ...

  13. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Your Blood Pressure Score is as Important ...

  14. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Shock Sore Throat Suicide Resources Home Safety ...

  15. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Puncture Wounds Teeth (Dental Emergencies) Sore Throat ...

  16. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Sore Throat Chest Pain Is ALWAYS A ...

  17. Heat loss from Buildings

    DEFF Research Database (Denmark)

    Karlsson, Kenneth; Næraa, Rikke

    1997-01-01

    Determination of heat loss coefficients for buildings in Denmark. The coefficient are determined for 15 building groups and 3 year intervals. They are based on the BBR-registre and assumptions of U-values(W/K*m2)and computed in a simple spreed sheet model.The results are used in the REVEILLE...

  18. Heating Systems Specialist.

    Science.gov (United States)

    Air Force Training Command, Sheppard AFB, TX.

    This instructional package is intended for use in training Air Force personnel enrolled in a program for apprentice heating systems specialists. Training includes instruction in fundamentals and pipefitting; basic electricity; controls, troubleshooting, and oil burners; solid and gas fuel burners and warm air distribution systems; hot water…

  19. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Adverse Drug Reactions Your Blood Pressure Score ...

  20. Flexible Heat Pipe

    Science.gov (United States)

    Bienert, W. B.; Wolf, D. A.

    1985-01-01

    Narrow Tube carries 10 watts or more to moving parts. Heat pipe 12 inches long and diameter of 0.312 inch (7.92mm). Bent to minimum radius of 2.5 blocks. Flexible section made of 321 stainless steel tubing (Cajon Flexible Tubing or equivalent). Evaporator and condenser made of oxygen free copper. Working fluid methanol.

  1. Sudurnes Regional Heating Corp.

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J. [ed.

    1996-11-01

    The Svartsengi geothermal area is close to the town of Grindavik on the Rekjanes peninsula and is part of an active fissure swarm, lined with crater-rows and open fissures and faults. The high-temperature area has an area of 2 sq. km and shows only limited signs of geothermal activity at the surface. The reservoir, however, contains lots of energy and at least 8 wells supply the Svartsengi Power Plant with steam. The steam is not useable for domestic heating purposes so that heat exchangers are used to heat cold groundwater with the steam. Some steam is also used for producing 16.4 MW{sub e} of electrical power. The article shows the distribution system piping hot water to nine towns and the Keflavik International Airport. The effluent brine from the Svartsengi Plant is disposed of into a surface pond, called the Blue Lagoon, popular to tourists and people suffering from psoriasis and other forms of eczema seeking therapeutic effects from the silica rich brine. This combined power plant and regional district heating system (cogeneration) is an interesting and unique design for the application of geothermal energy.

  2. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Seizures Vomiting and Diarrhea Sunburn and Sun ...

  3. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Vomiting and Diarrhea Shock Sprains and Strains ...

  4. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Choking (Heimlich Maneuver) Snake Bites Sore Throat ...

  5. Solar Energy: Heat Storage.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on heat storage is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  6. Financial heat machine

    Science.gov (United States)

    Khrennikov, Andrei

    2005-05-01

    We consider dynamics of financial markets as dynamics of expectations and discuss such a dynamics from the point of view of phenomenological thermodynamics. We describe a financial Carnot cycle and the financial analog of a heat machine. We see, that while in physics a perpetuum mobile is absolutely impossible, in economics such mobile may exist under some conditions.

  7. Heat stress in Tunisia

    African Journals Online (AJOL)

    RACHID BOURAOUI

    Humidity Index (THI), examine heat stress effects on lactating cows and to suggest potential management strategies that can be ... monthly temperature and relative humidity data from different weather stations. ... The objectives of the current work were to characterize the environmental conditions to which dairy cows are ...

  8. Heat exchanger. Varmeveksler

    Energy Technology Data Exchange (ETDEWEB)

    Rosman, I.E.; Wagner, W.R.

    1986-03-17

    The invention concerns a manifold for a plate-type heat exchanger, and includes a side channel connected the inlet of the manifold. The plates can be designed as an integral assembly together with the integrated side- and external end-manifolds as well. 16 drawings.

  9. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Chest Pain Is ALWAYS A Reason To ...

  10. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Sore Throat Suicide Puncture Wounds Resources Home ...

  11. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Sprains and Strains Sunburn and Sun Safety ...

  12. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Fact Sheet Health & Safety Tips Campaigns SUBSCRIBE Emergencies A-Z Share this! Home » Emergency 101 Heat-Related ... if the person becomes unconscious. READ IN EMERGENCIES A-Z Mental Health Emergencies - Waits for Care Grow ...

  13. POSSIBLE ROLE OF LOCALIZED PROTEIN DENATURATION IN THE MECHANISM OF INDUCTION OF THERMOTOLERANCE BY HEAT, SODIUM-ARSENITE AND ETHANOL

    NARCIS (Netherlands)

    BURGMAN, PWJJ; KAMPINGA, HH; KONINGS, AWT

    1993-01-01

    Heat, sodium-arsenite, and ethanol-induced thermotolerance are compared, especially with regard to the induced resistance of proteins of the particulate fraction (PF) against heat-induced denaturation. While all three agents induce thermotolerance as expressed as an enhanced survival after

  14. Enceladus Heat Pump Model

    Science.gov (United States)

    Matson, Dennis L.; Johnson, T. V.; Lunine, J. I.; Castillo-Rogez, J. C.

    2010-10-01

    Plume gas composition and the presence of dust grains rich in sodium salts [1,2] support a subsurface liquid as the source of the plumes observed at the South pole of Enceladus. We suggest that seawater circulating from the ocean to the surface supplies water, gas, dust and heat to the plumes. Our model needs only a percent or two of gas dissolved in the ocean, a value that is very much consistent with available observations ([1] suggest 10 percent of various gas species in the plume). As seawater comes up, pressure is released and bubbles form. Bubbly seawater is less dense than ice. Expanding gas provides lifting energy (cf. [6], [7]). The model delivers the materials that Postberg et al. [2] use for plume eruptions. Popping bubbles throw a fine spray that contains salt. This aerosol exits with the plume gas [2]. Most significant is the south polar heat flow >15 GW [4]. Water-borne oceanic heat is transferred to the surface ice. Less this heat, the water becomes colder, dissolves the bubble gases and becomes dense. It returns to the ocean via cracks in the ice. A large volume of ice is accessible via cracks SO THAT chemical interactions, heat exchange and other processes are possible. [1] Waite Jr et al., Nature, 460, 487 (2009). [2] Postberg et al., Nature, 459, 1098 (2009). [4] Howett et al BAAS., 41, 1122 (2009). [6] Crawford, and Stevenson, Icarus, 73, 66 (1988). [7] Murchie, and Head, LPS XVII, 583 (1986). This work was conducted at the Jet Propulsion Laboratory, California Institute of Technology under NASA contract, and for JIL under "Incentivazione alla mobilita' di studiosi straineri e italiani residenti all'estero" of Italy.

  15. Developmental acclimation to low or high humidity conditions affect starvation and heat resistance of Drosophila melanogaster.

    Science.gov (United States)

    Parkash, Ravi; Ranga, Poonam; Aggarwal, Dau Dayal

    2014-09-01

    Several Drosophila species originating from tropical humid localities are more resistant to starvation and heat stress than populations from high latitudes but mechanistic bases of such physiological changes are largely unknown. In order to test whether humidity levels affect starvation and heat resistance, we investigated developmental acclimation effects of low to high humidity conditions on the storage and utilization of energy resources, body mass, starvation survival, heat knockdown and heat survival of D. melanogaster. Isofemale lines reared under higher humidity (85% RH) stored significantly higher level of lipids and showed greater starvation survival hours but smaller in body size. In contrast, lines reared at low humidity evidenced reduced levels of body lipids and starvation resistance. Starvation resistance and lipid storage level were higher in females than males. However, the rate of utilization of lipids under starvation stress was lower for lines reared under higher humidity. Adult flies of lines reared at 65% RH and acclimated under high or low humidity condition for 200 hours also showed changes in resistance to starvation and heat but such effects were significantly lower as compared with developmental acclimation. Isofemale lines reared under higher humidity showed greater heat knockdown time and heat-shock survival. These laboratory observations on developmental and adult acclimation effects of low versus high humidity conditions have helped in explaining seasonal changes in resistance to starvation and heat of the wild-caught flies of D. melanogaster. Thus, we may suggest that wet versus drier conditions significantly affect starvation and heat resistance of D. melanogaster. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Heat pipe radiator. [for spacecraft waste heat rejection

    Science.gov (United States)

    Swerdling, B.; Alario, J.

    1973-01-01

    A 15,000 watt spacecraft waste heat rejection system utilizing heat pipe radiator panels was investigated. Of the several concepts initially identified, a series system was selected for more in-depth analysis. As a demonstration of system feasibility, a nominal 500 watt radiator panel was designed, built and tested. The panel, which is a module of the 15,000 watt system, consists of a variable conductance heat pipe (VCHP) header, and six isothermalizer heat pipes attached to a radiating fin. The thermal load to the VCHP is supplied by a Freon-21 liquid loop via an integral heat exchanger. Descriptions of the results of the system studies and details of the radiator design are included along with the test results for both the heat pipe components and the assembled radiator panel. These results support the feasibility of using heat pipes in a spacecraft waste heat rejection system.

  17. Prototype solar heating and combined heating cooling systems

    Science.gov (United States)

    1978-01-01

    The design and development of eight prototype solar heating and combined heating and cooling systems is discussed. The program management and systems engineering are reported, and operational test sites are identified.

  18. HEATING SETTINGS OF THE BURDEN HEATING FOR ELECTRO-MELTING

    Directory of Open Access Journals (Sweden)

    S. L. Rovin

    2006-01-01

    Full Text Available The work of the burden heating outfits for electrosmelting is considered. It is shown that equipping of heating units by the system KIP allows to receive considerable economic and ecological effect.

  19. Sensing the Heat Stress by Mammalian Cells

    Directory of Open Access Journals (Sweden)

    Cates Jordan

    2011-08-01

    Full Text Available Abstract Background The heat-shock response network controls the adaptation and survival of the cell against environmental stress. This network is highly conserved and is connected with many other signaling pathways. A key element of the heat-shock network is the heat-shock transcription factor-1 (HSF, which is transiently activated by elevated temperatures. HSF translocates to the nucleus upon elevated temperatures, forming homotrimeric complexes. The HSF homotrimers bind to the heat shock element on the DNA and control the expression of the hsp70 gene. The Hsp70 proteins protect cells from thermal stress. Thermal stress causes the unfolding of proteins, perturbing thus the pathways under their control. By binding to these proteins, Hsp70 allows them to refold and prevents their aggregation. The modulation of the activity of the hsp70-promoter by the intensity of the input stress is thus critical for cell's survival. The promoter activity starts from a basal level and rapidly increases once the stress is applied, reaches a maximum level and attenuates slowely back to the basal level. This phenomenon is the hallmark of many experimental studies and of all computational network analysis. Results The molecular construct used as a measure of the response to thermal stress is a Hsp70-GFP fusion gene transfected in Chinese hamster ovary (CHO cells. The time profile of the GFP protein depends on the transient activity, Transient(t, of the heat shock system. The function Transient(t depends on hsp70 promoter activity, transcriptional regulation and the translation initiation effects elicited by the heat stress. The GFP time profile is recorded using flow cytometry measurements, a technique that allows a quantitative measurement of the fluorescence of a large number of cells (104. The GFP responses to one and two heat shocks were measured for 261 conditions of different temperatures and durations. We found that: (i the response of the cell to two

  20. Suppression of first cleavage in the Mexican axolotl (Ambystoma mexicanum) by heat shock or hydrostatic pressure

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, L.L.; Armstrong, J.B.

    1981-12-01

    Androgenetic diploid axolotls were produced by ultraviolet inactivation of the egg pronucleus shortly after fertilization, followed by suppression of the first cleavage division by hydrostatic pressure or heat shock. After treatment at 14,000 psi for 8 minutes, diploidy was restored in 74% of the embryos, but only 0.8% survived to hatching. A 36-37 degrees C heat shock of 10-minutes duration, applied 5.5 hours after the eggs were collected, yielded a slightly lower percentage of diploids. However, the proportion surviving to hatching was significantly greater (up to 4.6%). A second generation of androgenetic diploids was produced from one of the oldest of the first generation males with a similar degree of success. The lack of significant improvement suggests that the low survival is due to the heat shock per se and not to the uncovering of recessive lethal genes carried by the parent.

  1. Survival paths through the forest

    DEFF Research Database (Denmark)

    Mogensen, Ulla Brasch

    when the information is high-dimensional e.g. when there are many thousands of genes or markers. In these situations machine learning methods such as the random forest can still be applied and provide reasonable prediction accuracy. The main focus in this talk is the performance of random forest...... in particular when the response is three-dimensional. In a diagnostic study of inflammatory bowel disease three classes of patients have to be diagnosed based on microarray gene-expression data. The performance of random forest is compared on a probability scale and on a classification scale to elastic net....... In survival analysis with competing risks I present an extension of random forest using time-dependent pseudo-values to build event risk prediction models. This approach is evaluated with data from Copenhagen stroke study. Further, I will explain how to use the R-package "pec" to evaluate random forests using...

  2. Optimal usage of low temperature heat sources to supply district heating by heat pumps

    DEFF Research Database (Denmark)

    Pieper, Henrik; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2017-01-01

    This paper presents a theoretical study on the optimal usage of different low temperature heat sources to supply district heating by heat pumps. The study is based on data for the Copenhagen region. The heat sources were prioritized based on the coefficient of performance calculated for each hour....... Groundwater, seawater and air heat sources were compared with each other as well as to a scenario consisting of a combination of these heat sources. In addition, base load and peak load units were included. Characteristic parameters were the coefficient of performance, the number of full load hours......% groundwater, 22% seawater and 0% air resulted in highest COP of 3.33 for the given heat demand. Furthermore, the implementation of rule based short term storage made peak units redundant. The variation in base load capacity showed that heat pumps utilizing the analyzed heat sources could perform very...

  3. Effect of environmental stress factors on the uptake and survival of Campylobacter jejuni in Acanthamoeba castellanii

    Directory of Open Access Journals (Sweden)

    Bui Xuan

    2012-10-01

    Full Text Available Abstract Background Campylobacter jejuni is a major cause of bacterial food-borne illness in Europe and North America. The mechanisms allowing survival in the environment and transmission to new hosts are not well understood. Environmental free-living protozoa may facilitate both processes. Pre-exposure to heat, starvation, oxidative or osmotic stresses encountered in the environment may affect the subsequent interaction of C. jejuni with free-living protozoa. To test this hypothesis, we examined the impact of environmental stress on expression of virulence-associated genes (ciaB, dnaJ, and htrA of C. jejuni and on its uptake by and intracellular survival within Acanthamoeba castellanii. Results Heat, starvation and osmotic stress reduced the survival of C. jejuni significantly, whereas oxidative stress had no effect. Quantitative RT-PCR experiments showed that the transcription of virulence genes was slightly up-regulated under heat and oxidative stresses but down-regulated under starvation and osmotic stresses, the htrA gene showing the largest down-regulation in response to osmotic stress. Pre-exposure of bacteria to low nutrient or osmotic stress reduced bacterial uptake by amoeba, but no effect of heat or oxidative stress was observed. Finally, C. jejuni rapidly lost viability within amoeba cells and pre-exposure to oxidative stress had no significant effect on intracellular survival. However, the numbers of intracellular bacteria recovered 5 h post-gentamicin treatment were lower with starved, heat treated or osmotically stressed bacteria than with control bacteria. Also, while ~1.5 × 103 colony forming unit/ml internalized bacteria could typically be recovered 24 h post-gentamicin treatment with control bacteria, no starved, heat treated or osmotically stressed bacteria could be recovered at this time point. Overall, pre-exposure of C. jejuni to environmental stresses did not promote intracellular survival in A. castellanii

  4. MRI survival guide; MRT Basiskurs

    Energy Technology Data Exchange (ETDEWEB)

    Cardoza, J. [Alta Imaging Medical Group and Magnetic Imaging Affiliates, Berkeley, CA (United States); Herfkens, R.J. [eds.] [Stanford Univ., CA (United States). Medical Center

    1999-07-01

    The book is a German translation of an American textbook with the original title ''MRI Survival Guide'' and is intended to serve as an introductory guide for beginners or a reference book for quick information. Readers will find information on the fundamentals of the technology and methodology of MRI as well as all details of relevance to practice in a precise and easy-to-grasp arrangement, covering all anatomic areas of interest, illustrations and descriptions of characteristic signs of pathologic processes, high-quality and unusually large-sized diagnostic pictures, a modern didactic concept for quick orientiation, including surveys, tables, and reproductions for visualisation of contents. (orig./CB) [German] Praktisch jeder Mediziner wird im Laufe seiner Berufstaetigkeit mit der MRT konfrontiert - unabhaengig davon ob in der Radiologie, Orthopaedie, Gynaekologie, Chirurgie, Neurologie oder sonstigen Fachrichtung. Das Buch ist eine Uebersetzung eines amerikanischen Lehrbuches mit dem Originaltitel ''MRI Survival Guide'' und will eine wesentliche Erleichterung als 'Ueberlebenshandbuch fuer die MRT' bieten: - Darstellung aller relevanten Grundlagen zu Technik, verschiedenen Sequenzen und Methodik der MRT - knapp und mit maximalem Praxisbezug - Beruecksichtigung aller moeglichen Untersuchungsregionen und strukturierte Orientierung daran (Gehirn, Wirbelsaeule, Kopf/Nacken, Brustkorb, Bauch, Becken, Muskel-Skelett-Bereich) - Illustration und Beschreibung der charakteristischen Erscheinungsmerkmale aller haeufigen pathologischen Prozesse im MRT, inklusive direkt umsetzbarer differentialdiagnostischer Abgrenzungskriterien - hochwertiges und aussergewoehnlich gross dimensioniertes Bildmaterial - modernes, didaktisches Konzept fuer die rasche Orientierung mit vielen Uebersichten, Tabellen und Abbildungen zur Visualisierung der Inhalte, Praxistips und Aufzeigen von Fehlermoeglichkeiten - zum Einstieg, zur Rekapitulation

  5. Ion and electron heating in ICRF heating experiments on LHD

    Energy Technology Data Exchange (ETDEWEB)

    Saito, K. [Nagoya Univ. (Japan). Faculty of Engineering; Kumazawa, R.; Mutoh, T. [National Inst. for Fusion Science, Toki, Gifu (Japan)] [and others

    2001-02-01

    This paper reports on the Ion Cyclotron Range of Frequency (ICRF) heating conducted in 1999 in the 3rd experimental campaign on the Large Helical Device (LHD) with an emphasis on the optimization of the heating regime. Specifically, an exhaustive study of seven different heating regimes was carried out by changing the RF frequency relative to the magnetic field intensity, and the dependence of the heating efficiency on H-minority concentration was investigated. It was found in the experiment that both ion and electron heating are attainable with the same experimental setup by properly choosing the frequency relative to the magnetic field intensity. In the cases of both electron heating and ion heating, the power absorption efficiency depends on the minority ion concentration. An optimum minority concentration exists in the ion heating case while, in the electron heating case, the efficiency increases with concentration monotonically. A simple model calculation is introduced to provide a heuristic understanding of these experimental results. Among the heating regimes examined in this experiment, one of the ion heating regimes was finally chosen as the optimized heating regime and various high performance discharges were realized with it. (author)

  6. Heat transfer research on enhanced heating surfaces in pool boiling

    Science.gov (United States)

    Kalawa, Wojciech; Wójcik, Tadeusz M.; Piasecka, Magdalena

    The paper focuses on the analysis of the enhanced surfaces in such applications as boiling heat transfer. The testing measurement module with enhanced heating surfaces was used for pool boiling research. Pool boiling experiments were conducted with distilled water at atmospheric pressure in the vessel using an enhanced sample as the bottom heating surface. The samples are soldered to a copper heating block of the round cross-section .They were placed: in the fluid (saturation temperature measurement), under the sample for temperature determination. A vessel made of four flat glass panes was used for visualization. The heated surfaces in contact with the fluid differed in roughness were smooth or enhanced. This paper analyzes the effects of the microstructured heated surface on the heat transfer coefficient. The results are presented as relationships between the heat transfer coefficient and the heat flux and as boiling curves. The experimental data obtained for the two types of enhanced heated surfaces was compared with the results recorded for the smooth heated surface. The highest local values of the heat transfer coefficient were reported for the enhanced surfaces.

  7. Industrial Heat Pump for a High Temperature District Heating Application

    DEFF Research Database (Denmark)

    Poulsen, Claus Nørgaard

    by excess thermal energy from thermal solar panels. An industrial heat pump system using the natural refrigerant ammonia, is extracting the thermal energy from the storage when needed, and produce hot water at 85°C, for the district heating grid. The heat pump also acts as contributor to electricity grid...

  8. High temperature heat exchange: nuclear process heat applications

    Energy Technology Data Exchange (ETDEWEB)

    Vrable, D.L.

    1980-09-01

    The unique element of the HTGR system is the high-temperature operation and the need for heat exchanger equipment to transfer nuclear heat from the reactor to the process application. This paper discusses the potential applications of the HTGR in both synthetic fuel production and nuclear steel making and presents the design considerations for the high-temperature heat exchanger equipment.

  9. A heat pipe quick disconnect

    Science.gov (United States)

    Alario, J. P.; Otterstedt, P. J.

    1985-07-01

    This paper reports the proof of concept demonstration of a heat pipe quick disconnect being developed for the space constructible radiator system. The disconnect provides a maintainable coupling between the heat pipe evaporator, which is brazed to a mating heat exchanger, and the replaceable condenser section of a monogroove heat pipe radiator element. Test results, with pressurized nitrogen gas, confirm low leakage rates in both demated and mated configurations. Comparative thermal tests in a working 3 m (10 ft) test bed heat pipe using ammonia fluid revealed a 30 percent decrease in heat transport due to the additional minor pressure losses from the quick disconnect. The bulk of this loss is attributed to the transition section that joins the two adjacent heat pipe flow channels to the separated liquid and vapor passages within the disconnect coupling. It would be possible to decrease this overall loss in heat transport to under 10 percent with a redesigned transition section.

  10. Arc Heated Scramjet Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Arc Heated Scramjet Test Facility is an arc heated facility which simulates the true enthalpy of flight over the Mach number range of about 4.7 to 8 for free-jet...

  11. Transient heating of moving objects

    Directory of Open Access Journals (Sweden)

    E.I. Baida

    2014-06-01

    Full Text Available A mathematical model of transient and quasistatic heating of moving objects by various heat sources is considered. The mathematical formulation of the problem is described, examples of thermal calculation given.

  12. Earth's heat budget: Clairvoyant geoneutrinos

    Science.gov (United States)

    Korenaga, Jun

    2011-09-01

    The quantity of heat generated by radioactive decay in Earth's interior is controversial. Measurements of geoneutrinos emitted from the mantle during this decay indicate that this source contributes only about half of Earth's total outgoing heat flux.

  13. VTX HyHeat Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this project Orbital Technologies Corporation (ORBITEC) will utilize its unique vortex propulsion technology to develop a high-capacity heating system to heat...

  14. Heat Pumps in Subarctic Areas

    DEFF Research Database (Denmark)

    Atlason, Reynir Smari; Oddsson, Gudmundur Valur; Unnthorsson, Runar

    2017-01-01

    Geothermal heat pumps use the temperature difference between inside and outside areas to modify a refrigerant, either for heating or cooling. Doing so can lower the need for external heating energy for a household to some extent. The eventual impact depends on various factors, such as the external...... source for heating or cooling and the temperature difference. The use of geothermal heat pumps, and eventual benefits has not been studied in the context of frigid areas, such as in Iceland. In Iceland, only remote areas do not have access to district heating from geothermal energy where households may...... the Icelandic energy authority for the analysis. Findings show that a majority of households (83%) used between 20 and 50 MWh annually prior to installing a heat pump system (mean = 37.8 MWh). On average, households used approximately 26 MWh after installing a heat pump. When installing a small pump (5 to 9 k...

  15. Hybrid Heat Exchangers

    Science.gov (United States)

    Tu, Jianping Gene; Shih, Wei

    2010-01-01

    A hybrid light-weight heat exchanger concept has been developed that uses high-conductivity carbon-carbon (C-C) composites as the heat-transfer fins and uses conventional high-temperature metals, such as Inconel, nickel, and titanium as the parting sheets to meet leakage and structural requirements. In order to maximize thermal conductivity, the majority of carbon fiber is aligned in the fin direction resulting in 300 W/m.K or higher conductivity in the fin directions. As a result of this fiber orientation, the coefficient of thermal expansion (CTE) of the C-C composite in both non-fiber directions matches well with the CTE of various high-temperature metal alloys. This allows the joining of fins and parting sheets by using high-temperature braze alloys.

  16. Making Heat Visible

    Science.gov (United States)

    Goodhew, Julie; Pahl, Sabine; Auburn, Tim; Goodhew, Steve

    2015-01-01

    Householders play a role in energy conservation through the decisions they make about purchases and installations such as insulation, and through their habitual behavior. The present U.K. study investigated the effect of thermal imaging technology on energy conservation, by measuring the behavioral effect after householders viewed images of heat escaping from or cold air entering their homes. In Study 1 (n = 43), householders who received a thermal image reduced their energy use at a 1-year follow-up, whereas householders who received a carbon footprint audit and a non-intervention control demonstrated no change. In Study 2 (n = 87), householders were nearly 5 times more likely to install draught proofing measures after seeing a thermal image. The effect was especially pronounced for actions that addressed an issue visible in the images. Findings indicate that using thermal imaging to make heat loss visible can promote energy conservation. PMID:26635418

  17. Superradiant Quantum Heat Engine.

    Science.gov (United States)

    Hardal, Ali Ü C; Müstecaplıoğlu, Özgür E

    2015-08-11

    Quantum physics revolutionized classical disciplines of mechanics, statistical physics, and electrodynamics. One branch of scientific knowledge however seems untouched: thermodynamics. Major motivation behind thermodynamics is to develop efficient heat engines. Technology has a trend to miniaturize engines, reaching to quantum regimes. Development of quantum heat engines (QHEs) requires emerging field of quantum thermodynamics. Studies of QHEs debate whether quantum coherence can be used as a resource. We explore an alternative where it can function as an effective catalyst. We propose a QHE which consists of a photon gas inside an optical cavity as the working fluid and quantum coherent atomic clusters as the fuel. Utilizing the superradiance, where a cluster can radiate quadratically faster than a single atom, we show that the work output becomes proportional to the square of the number of the atoms. In addition to practical value of cranking up QHE, our result is a fundamental difference of a quantum fuel from its classical counterpart.

  18. Adaptive Heat Engine.

    Science.gov (United States)

    Allahverdyan, A E; Babajanyan, S G; Martirosyan, N H; Melkikh, A V

    2016-07-15

    A major limitation of many heat engines is that their functioning demands on-line control and/or an external fitting between the environmental parameters (e.g., temperatures of thermal baths) and internal parameters of the engine. We study a model for an adaptive heat engine, where-due to feedback from the functional part-the engine's structure adapts to given thermal baths. Hence, no on-line control and no external fitting are needed. The engine can employ unknown resources; it can also adapt to results of its own functioning that make the bath temperatures closer. We determine resources of adaptation and relate them to the prior information available about the environment.

  19. A sublimation heat engine.

    Science.gov (United States)

    Wells, Gary G; Ledesma-Aguilar, Rodrigo; McHale, Glen; Sefiane, Khellil

    2015-03-03

    Heat engines are based on the physical realization of a thermodynamic cycle, most famously the liquid-vapour Rankine cycle used for steam engines. Here we present a sublimation heat engine, which can convert temperature differences into mechanical work via the Leidenfrost effect. Through controlled experiments, quantified by a hydrodynamic model, we show that levitating dry-ice blocks rotate on hot turbine-like surfaces at a rate controlled by the turbine geometry, temperature difference and solid material properties. The rotational motion of the dry-ice loads is converted into electric power by coupling to a magnetic coil system. We extend our concept to liquid loads, generalizing the realization of the new engine to both sublimation and the instantaneous vapourization of liquids. Our results support the feasibility of low-friction in situ energy harvesting from both liquids and ices. Our concept is potentially relevant in challenging situations such as deep drilling, outer space exploration or micro-mechanical manipulation.

  20. Heat-resistant materials

    CERN Document Server

    1997-01-01

    This handbook covers the complete spectrum of technology dealing with heat-resistant materials, including high-temperature characteristics, effects of processing and microstructure on high-temperature properties, materials selection guidelines for industrial applications, and life-assessment methods. Also included is information on comparative properties that allows the ranking of alloy performance, effects of processing and microstructure on high-temperature properties, high-temperature oxidation and corrosion-resistant coatings for superalloys, and design guidelines for applications involving creep and/or oxidation. Contents: General introduction (high-temperature materials characteristics, and mechanical and corrosion properties, and industrial applications); Properties of Ferrous Heat-Resistant Alloys (carbon, alloy, and stainless steels; alloy cast irons; and high alloy cast steels); Properties of superalloys (metallurgy and processing, mechanical and corrosion properties, degradation, and protective coa...

  1. Impedance and component heating

    CERN Document Server

    Métral, E; Mounet, N; Pieloni, T; Salvant, B

    2015-01-01

    The impedance is a complex function of frequency, which represents, for the plane under consideration (longitudinal, horizontal or vertical), the force integrated over the length of an element, from a “source” to a “test” wave, normalized by their charges. In general, the impedance in a given plane is a nonlinear function of the test and source transverse coordinates, but it is most of the time sufficient to consider only the first few linear terms. Impedances can influence the motion of trailing particles, in the longitudinal and in one or both transverse directions, leading to energy loss, beam instabilities, or producing undesirable secondary effects such as excessive heating of sensitive components at or near the chamber wall, called beam-induced RF heating. The LHC performance limitations linked to impedances encountered during the 2010-2012 run are reviewed and the currently expected situation during the HL-LHC era is discussed.

  2. The projective heat map

    CERN Document Server

    Schwartz, Richard Evan

    2017-01-01

    This book introduces a simple dynamical model for a planar heat map that is invariant under projective transformations. The map is defined by iterating a polygon map, where one starts with a finite planar N-gon and produces a new N-gon by a prescribed geometric construction. One of the appeals of the topic of this book is the simplicity of the construction that yet leads to deep and far reaching mathematics. To construct the projective heat map, the author modifies the classical affine invariant midpoint map, which takes a polygon to a new polygon whose vertices are the midpoints of the original. The author provides useful background which makes this book accessible to a beginning graduate student or advanced undergraduate as well as researchers approaching this subject from other fields of specialty. The book includes many illustrations, and there is also a companion computer program.

  3. Microencapsulation of alginate-immobilized bagasse with Lactobacillus rhamnosus NRRL 442: enhancement of survivability and thermotolerance.

    Science.gov (United States)

    Shaharuddin, Shahrulzaman; Muhamad, Ida Idayu

    2015-03-30

    The aim of this research was to enhance the survivability of Lactobacillus rhamnosus NRRL 442 against heat exposure via a combination of immobilization and microencapsulation processes using sugarcane bagasse (SB) and sodium alginate (NaA), respectively. The microcapsules were synthesized using different alginate concentration of 1, 2 and 3% and NaA:SB ratio of 1:0, 1:1 and 1:1.5. This beneficial step of probiotic immobilization before microencapsulation significantly enhanced microencapsulation efficiency and cell survivability after heat exposure of 90°C for 30s. Interestingly, the microcapsule of SB-immobilized probiotic could obtain protection from heat using microencapsulation of NaA concentration as low as 1%. SEM images illustrated the incorporation of immobilized L. rhamnosus within alginate matrices and its changes after heat exposure. FTIR spectra confirmed the change in functional bonding in the presence of sugarcane bagasse, probiotic and alginate. The results demonstrated a great potential in the synthesis of heat resistant microcapsules for probiotic. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Convective heat transfer in non-uniformly heated corrugated slots

    Science.gov (United States)

    Abtahi, Arman; Floryan, J. M.

    2017-10-01

    An analysis of heat transfer in non-uniformly heated corrugated slots has been carried out. A sinusoidal corrugation is placed at the lower plate that is exposed to heating consisting of uniform and sinusoidal components, while the upper smooth plate is kept isothermal. The phase difference ΩTL describes the shift between the heating and geometric non-uniformities. The analysis is limited to heating conditions that do not give rise to secondary motions. Depending on ΩTL, the conductive heat flow is directed either upwards, or downwards, or is eliminated. Its magnitude is smallest for the long-wavelength systems and largest for the short-wavelength systems, and it increases proportionally to the corrugation amplitude and heating intensity. The same heating creates horizontal temperature gradients that give rise to convection whose form depends on ΩTL. Convection consists of counter-rotating rolls with the size dictated by the system wavelength when the hot spots (points of maximum temperature) overlap either with the corrugation tips or with the corrugation bottoms. Thermal drift forms for all other values of ΩTL. The convective heat flow is always directed upwards, and it is the largest in systems with wavelengths comparable to the slot height. The magnitude of the overall heat flow increases proportionally to the heating intensity when conductive effects dominate and proportionally to the second power of the heating intensity when convection dominates. It also increases proportionally to the corrugation amplitude. The system characteristics are dictated by convection when the relative position of the heating and corrugation patterns eliminates conduction. Addition of the uniform heating component amplifies the above processes, while uniform cooling reduces them. The processes described above are qualitatively similar for all Prandtl numbers of practical interest with the magnitude of the convective heat flow increasing with Pr.

  5. Solar-heating module

    Science.gov (United States)

    Christensen, D. L.

    1978-01-01

    Comprehensive set of engineering drawings and instructions for installation, operation, repair, and maintenance are available for module that provides hot-air or hot-water needs for residence or commercial building. It can accommodate solar collectors of various sizes and types. It can provide utility, workshop, or storage space, in addition to providing hot water or hot air. Extensive insulation minimizes heat losses in structure and in storage and fluid-handling subsystems.

  6. Urban heat island 1

    DEFF Research Database (Denmark)

    Bühler, Oliver; Jensen, Marina Bergen; Petersen, Karen Sejr

    2010-01-01

    Urban Heat Island beskriver det forhold, at temperaturen i byområder er højere end temperaturen i tilgrænsede landområder. Årsagen hertil ligger i den urbane arealanvendelse, hvor en mindre andel af arealerne er dækket af vegetation, og en større andel består af forseglede arealer....

  7. SPECIFIC HEAT INDICATOR

    Science.gov (United States)

    Horn, F.L.; Binns, J.E.

    1961-05-01

    Apparatus for continuously and automatically measuring and computing the specific heat of a flowing solution is described. The invention provides for the continuous measurement of all the parameters required for the mathematical solution of this characteristic. The parameters are converted to logarithmic functions which are added and subtracted in accordance with the solution and a null-seeking servo reduces errors due to changing voltage drops to a minimum. Logarithmic potentiometers are utilized in a unique manner to accomplish these results.

  8. Getting the Heat Out

    Science.gov (United States)

    2009-03-04

    to 20g  Nanostructured wick for enhanced heat transfer and fluid transport  Structural, flexible, thin, & light-weight materials that match the TEC ...Flexible, TEC -matched Casing Nanostructured WickVapor Cavity Approved For Public Release, Distribution Unlimited TJunction A New Thermal Opportunity chip...complements the Thermal Ground Plane (TGP) program. Microtechnologies for Air Cooled Exchangers (MACE) Nano -textured fins to enhance convection surface

  9. Heat Transfer Analogies

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, A.

    1965-11-15

    This report contains descriptions of various analogues utilised to study different steady-state and unsteady-state heat transfer problems. The analogues covered are as follows: 1 . Hydraulic: a) water flow b) air flow 2. Membrane 3. Geometric Electrical: a) Electrolytic-tank b) Conducting sheet 4. Network; a) Resistance b) R-C A comparison of the different analogues is presented in the form of a table.

  10. Nonadiabatic electron heat pump

    OpenAIRE

    Rey, Miguel; Strass, Michael; Kohler, Sigmund; Hänggi, Peter; Sols, Fernando

    2006-01-01

    We investigate a mechanism for extracting heat from metallic conductors based on the energy-selective transmission of electrons through a spatially asymmetric resonant structure subject to ac driving. This quantum refrigerator can operate at zero net electronic current as it replaces hot by cold electrons through two energetically symmetric inelastic channels. We present numerical results for a specific heterostructure and discuss general trends. We also explore the conditions under which the...

  11. Characteristics of model heat exchanger

    Science.gov (United States)

    Kolínský, Jan

    2017-09-01

    The aim of this paper is thermal analysis of model water to water heat exchanger at different mass flow rates. Experimental study deals with determination of total heat transfer - power of the heat exchanger. Furthermore the paper deals with analysis of heat exchanger charakcteristic using a definition of thermal efficiency. It is demonstrated that it is advisable to monitor the dependence of thermal efficiency and flow ratio.

  12. Review of Fractal Heat Exchangers

    OpenAIRE

    Huang, Zhiwei; Hwang, Yunho; Aute, Vikrant; Radermacher, Reinhard

    2016-01-01

    Nature has inspired many scientists and engineers to solve problems through observation and mimicry. One such example is heat transfer enhancement. The enormous natural heat and mass transfer phenomena have led engineers to seek solutions to heat transfer enhancement problems from nature. Fractal geometries are found in respiratory and vascular systems of plants and animals, such as blood vessels, human lungs, leaves, coastlines, etc. Inspired by this, fractal heat exchangers have been develo...

  13. Nucleate boiling heat transfer

    Energy Technology Data Exchange (ETDEWEB)

    Saiz Jabardo, J.M. [Universidade da Coruna (Spain). Escola Politecnica Superior], e-mail: mjabardo@cdf.udc.es

    2009-07-01

    Nucleate boiling heat transfer has been intensely studied during the last 70 years. However boiling remains a science to be understood and equated. In other words, using the definition given by Boulding, it is an 'insecure science'. It would be pretentious of the part of the author to explore all the nuances that the title of the paper suggests in a single conference paper. Instead the paper will focus on one interesting aspect such as the effect of the surface microstructure on nucleate boiling heat transfer. A summary of a chronological literature survey is done followed by an analysis of the results of an experimental investigation of boiling on tubes of different materials and surface roughness. The effect of the surface roughness is performed through data from the boiling of refrigerants R-134a and R-123, medium and low pressure refrigerants, respectively. In order to investigate the extent to which the surface roughness affects boiling heat transfer, very rough surfaces (4.6 {mu}m and 10.5 {mu}m ) have been tested. Though most of the data confirm previous literature trends, the very rough surfaces present a peculiar behaviour with respect to that of the smoother surfaces (Ra<3.0 {mu}m). (author)

  14. Earth's surface heat flux

    Directory of Open Access Journals (Sweden)

    J. H. Davies

    2010-02-01

    Full Text Available We present a revised estimate of Earth's surface heat flux that is based upon a heat flow data-set with 38 347 measurements, which is 55% more than used in previous estimates. Our methodology, like others, accounts for hydrothermal circulation in young oceanic crust by utilising a half-space cooling approximation. For the rest of Earth's surface, we estimate the average heat flow for different geologic domains as defined by global digital geology maps; and then produce the global estimate by multiplying it by the total global area of that geologic domain. The averaging is done on a polygon set which results from an intersection of a 1 degree equal area grid with the original geology polygons; this minimises the adverse influence of clustering. These operations and estimates are derived accurately using methodologies from Geographical Information Science. We consider the virtually un-sampled Antarctica separately and also make a small correction for hot-spots in young oceanic lithosphere. A range of analyses is presented. These, combined with statistical estimates of the error, provide a measure of robustness. Our final preferred estimate is 47±2 TW, which is greater than previous estimates.

  15. Stirling Engine Heat Pump

    Science.gov (United States)

    Kagawa, Noboru

    Recent advances in the feasibility studies related to the Stirling engines and Stirling engine heat pumps which have been considered attractive due to their promising role in helping to solve the global environmental and energy problems,are reviewed. This article begins to describe the brief history of the Stirling engines and theoretical thermodynamic analysis of the Stirling cycle in order to understand several advantages on the Stirling engine. Furthermore,they could throw light on our question why the dream engines had not been promoted to practical applications during two hundred years. The present review shows that the Stirling engines with several unique advantages including 30 to 40% thermal efficiency and preferable exhaust characteristics,had been designed and constructed by recent tackling for the development of the advanced automobile and other applications using them. Based on the current state of art,it is being provided to push the Stirling engines combined with heat pumps based on the reversed Rankine cycle to the market. At present,however, many problems, especially for the durability, cost, and delicate engine parts must be enforced to solve. In addition,there are some possibilities which can increase the attractiveness of the Stirling engines and heat pumps. The review closes with suggestions for further research.

  16. Autonomous rotor heat engine

    Science.gov (United States)

    Roulet, Alexandre; Nimmrichter, Stefan; Arrazola, Juan Miguel; Seah, Stella; Scarani, Valerio

    2017-06-01

    The triumph of heat engines is their ability to convert the disordered energy of thermal sources into useful mechanical motion. In recent years, much effort has been devoted to generalizing thermodynamic notions to the quantum regime, partly motivated by the promise of surpassing classical heat engines. Here, we instead adopt a bottom-up approach: we propose a realistic autonomous heat engine that can serve as a test bed for quantum effects in the context of thermodynamics. Our model draws inspiration from actual piston engines and is built from closed-system Hamiltonians and weak bath coupling terms. We analytically derive the performance of the engine in the classical regime via a set of nonlinear Langevin equations. In the quantum case, we perform numerical simulations of the master equation. Finally, we perform a dynamic and thermodynamic analysis of the engine's behavior for several parameter regimes in both the classical and quantum case and find that the latter exhibits a consistently lower efficiency due to additional noise.

  17. Heating solar coronal holes

    Science.gov (United States)

    Parker, E. N.

    1991-01-01

    It has been shown that the coronal hole, and the associated high-speed stream in the solar wind, are powered by a heat input of the order of 500,000 ergs/sq cm s, with most of the heat injected in the first 1-2 solar radii, and perhaps 100,000 ergs/sq cm s introduced at distances of several solar radii to provide the high speed of the issuing solar wind. The traditional view has been that this energy is obtained from Alfven waves generated in the subphotospheric convection, which dissipate as they propagate outward, converting the wave energy into heat. This paper reviews the generation of waves and the known wave dissipation mechanisms, to show that the necessary Alfven waves are not produced under the conditions presently understood to exist in the sun, nor would such waves dissipate significantly in the first 1-2 solar radii if they existed. Wave dissipation occurs only over distances of the order of 5 solar radii or more.

  18. Heat driven pulse pump

    Science.gov (United States)

    Benner, Steve M (Inventor); Martins, Mario S. (Inventor)

    2000-01-01

    A heat driven pulse pump includes a chamber having an inlet port, an outlet port, two check valves, a wick, and a heater. The chamber may include a plurality of grooves inside wall of the chamber. When heated within the chamber, a liquid to be pumped vaporizes and creates pressure head that expels the liquid through the outlet port. As liquid separating means, the wick, disposed within the chamber, is to allow, when saturated with the liquid, the passage of only liquid being forced by the pressure head in the chamber, preventing the vapor from exiting from the chamber through the outlet port. A plurality of grooves along the inside surface wall of the chamber can sustain the liquid, which is amount enough to produce vapor for the pressure head in the chamber. With only two simple moving parts, two check valves, the heat driven pulse pump can effectively function over the long lifetimes without maintenance or replacement. For continuous flow of the liquid to be pumped a plurality of pumps may be connected in parallel.

  19. Convective Heating of the LIFE Engine Target During Injection

    Energy Technology Data Exchange (ETDEWEB)

    Holdener, D S; Tillack, M S; Wang, X R

    2011-10-24

    Target survival in the hostile, high temperature xenon environment of the proposed Laser Inertial Fusion Energy (LIFE) engine is critical. This work focuses on the flow properties and convective heat load imposed upon the surface of the indirect drive target while traveling through the xenon gas. While this rarefied flow is traditionally characterized as being within the continuum regime, it is approaching transition where conventional CFD codes reach their bounds of operation. Thus ANSYS, specifically the Navier-Stokes module CFX, will be used in parallel with direct simulation Monte Carlo code DS2V and analytically and empirically derived expressions for heat transfer to the hohlraum for validation. Comparison of the viscous and thermal boundary layers of ANSYS and DS2V were shown to be nearly identical, with the surface heat flux varying less than 8% on average. From the results herein, external baffles have been shown to reduce this heat transfer to the sensitive laser entrance hole (LEH) windows and optimize target survival independent of other reactor parameters.

  20. Heat pipes as perspective base elements of heat recovery in heat supply and ventilating systems

    Directory of Open Access Journals (Sweden)

    Matveev Andrey

    2017-01-01

    Full Text Available Thermotechnical characteristics of heat pipes are considered as high-efficient heat-transfer devices, which can provide energy-saving technologies for heat supply and ventilating systems and for different branches of industry. Thermotechnical and working (”performance capability” characteristics of heat pipes are investigated. By ”performance capability” of heat pipes and heat-transfer devices on heat pipes we mean the system state, where it can perform set functions and keep parameter values (thermal power, conductivity, thermal resistance, heat-transfer coefficient, temperature level and differential, etc. within the regulations of standardized specifications. The article presents theoretical and experimental methods of «gaslock» length determination on noncondensable gases during long-lasting tests of ammonia heat pipes made of aluminum shape АS – КRА 7.5 – R1 (alloy АD – 31. The paper gives results of research of thermotechnical characteristics of heat pipes in horizontal and vertical states (separate and as a set part while using different systems of thermal insulation. The obtained results of thermotechnical and resource tests show the advantages of ammonia heat pipes as basic elements for heat exchanger design in heating and ventilation systems.

  1. Heat distribution and the future competitiveness of district heating

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Urban; Werner, Sven [School of Business and Engineering, Halmstad University, PO Box 823, SE-30118 Halmstad (Sweden)

    2011-03-15

    The competitiveness of present and future district heating systems can be at risk when residential and service sector heat demands are expected to decrease in the future. In this study, the future competitiveness of district heating has been examined by an in depth analysis of the distribution capital cost at various city characteristics, city sizes, and heat demands. Hereby, this study explores an important market condition often neglected or badly recognised in traditional comparisons between centralised and decentralised heat supply. By a new theoretical approach, the traditional and empirical expression for linear heat density is transformed into an analytical expression that allows modelling of future distribution capital cost levels also in areas where no district heating exists today. The independent variables in this new analytical expression are population density, specific building space, specific heat demand and effective width. Model input data has primarily been collected from national and European statistical sources on heat use, city populations, city districts and residential living areas. Study objects were 83 cities in Belgium, Germany, France, and the Netherlands. The average heat market share for district heat within these cities was 21% during 2006. The main conclusion is that the future estimated capital costs for district heat distribution in the study cities are rather low, since the cities are very dense. At the current situation, a market share of 60% can be reached with a marginal distribution capital cost of only 2.1 EUR/GJ, corresponding to an average distribution capital cost of 1.6 EUR/GJ. The most favourable conditions appear in large cities and in inner city areas. In the future, there is a lower risk for reduced competitiveness due to reduced heat demands in these areas, since the increased distribution capital cost is low compared to the typical prices of district heat and competing heat supply. However, district heating will lose

  2. Characterization of industrial process waste heat and input heat streams

    Energy Technology Data Exchange (ETDEWEB)

    Wilfert, G.L.; Huber, H.B.; Dodge, R.E.; Garrett-Price, B.A.; Fassbender, L.L.; Griffin, E.A.; Brown, D.R.; Moore, N.L.

    1984-05-01

    The nature and extent of industrial waste heat associated with the manufacturing sector of the US economy are identified. Industry energy information is reviewed and the energy content in waste heat streams emanating from 108 energy-intensive industrial processes is estimated. Generic types of process equipment are identified and the energy content in gaseous, liquid, and steam waste streams emanating from this equipment is evaluated. Matchups between the energy content of waste heat streams and candidate uses are identified. The resultant matrix identifies 256 source/sink (waste heat/candidate input heat) temperature combinations. (MHR)

  3. Kajian Eksperimen Heat Exchahger Pada Heat Pump Menggunakan Refrijeran Hidrokarbon

    OpenAIRE

    Kusnandar; Gusniawan; Fajar Sentosa

    2016-01-01

    Heat pump or usually known as pump energy is a device that can cooling and heating to be used, which functions as a cooling evaporator can be direct replace to heating as a function of the condenser using a reversing valve.. Using heat exchangers in the heat pump system is installed on the suction line and discharge line, so it will give the suction line temperature changes will be higher and discharge line temperatures will be lower, resulting in a greater cooling effect and li...

  4. Milk fouling in heat exchangers

    NARCIS (Netherlands)

    Jeurnink, T.J.M.

    1996-01-01


    The mechanisms of fouling of heat exchangers by milk were studied. Two major fouling mechanisms were indentified during the heat treatment of milk: (i) the formation and the subsequent deposition of activated serum protein molecules as a result of the heat denaturation; (ii) the

  5. Ventilation and Heat Recovering System

    Directory of Open Access Journals (Sweden)

    Olga Bancea

    2007-01-01

    Full Text Available Some aspects concerning the heat reducing for ventilation, achieved by using heat recovering components and a combined heating--ventilating system, assuring both comfort and human health are presented. The floor imbedded systems together with air outlets elements could fulfill all the aesthetically desires, as well as comfort and they are ideal for family houses.

  6. Climate Fundamentals for Solar Heating.

    Science.gov (United States)

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    The design of any solar heating system is influenced heavily by climate; in this bulletin, information on climate as related to solar heating is as related to solar heating is provided. Topics discussed include: (1) solar radiation; (2) degree days; (3) climate and calculations which make use of solar radiation and degree days; and (4)…

  7. Heating being put into service

    CERN Multimedia

    2016-01-01

    The SMB-SE group would like to inform you that, the central heating will start this year, on Monday 3 October 2016, and will be progressively and depending on the weather forecast put into service throughout. All buildings will have heating within the following few days. Thank you for your understanding. The CERN heating team SMB-SE

  8. Staged regenerative sorption heat pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1995-01-01

    A regenerative adsorbent heat pump process and system for cooling and heating a space. A sorbent is confined in a plurality of compressors of which at least four are first stage and at least four are second stage. The first stage operates over a first pressure region and the second stage over a second pressure region which is higher than the first. Sorbate from the first stage enters the second stage. The sorbate loop includes a condenser, expansion valve, evaporator and the compressors. A single sorbate loop can be employed for single-temperature-control such as air conditioning and heating. Two sorbate loops can be used for two-temperature-control as in a refrigerator and freezer. The evaporator temperatures control the freezer and refrigerator temperatures. Alternatively the refrigerator temperature can be cooled by the freezer with one sorbate loop. A heat transfer fluid is circulated in a closed loop which includes a radiator and the compressors. Low temperature heat is exhausted by the radiator. High temperature heat is added to the heat transfer fluid entering the compressors which are desorbing vapor. Heat is transferred from compressors which are sorbing vapor to the heat transfer fluid, and from the heat transfer fluid to the compressors which are desorbing vapor. Each compressor is subjected to the following phases, heating to its highest temperature, cooling down from its highest temperature, cooling to its lowest temperature, and warming up from its lowest temperature. The phases are repeated to complete a cycle and regenerate heat.

  9. Shared Frailty Model for Left-Truncated Multivariate Survival Data

    DEFF Research Database (Denmark)

    Jensen, Henrik; Brookmeyer, Ron; Aaby, Peter

    multivariate survival data, left truncation, multiplicative hazard model, shared gamma frailty, conditional model, piecewise exponential model, childhood survival......multivariate survival data, left truncation, multiplicative hazard model, shared gamma frailty, conditional model, piecewise exponential model, childhood survival...

  10. The Survival and Birth of Firms

    OpenAIRE

    Leon Shilton; Craig Stanley

    1999-01-01

    Using a modified form of the location quotient, a "growth quotient," this study traces the survival and growth for the headquarters of publicly listed firms in the United States. At the county level, the spatial concentrations of headquarters listed in 1997 are correlated with the spatial concentrations of corporate headquarters that survived from 1986 though 1996. Counties that house the headquarters of many different survival firms continue to spawn new headquarters. Counties with headquart...

  11. Compact seasonal PCM heat storage for solar heating systems

    DEFF Research Database (Denmark)

    Dannemand, Mark

    Space heating of buildings and preparation of domestic hot water accounts for a large part of the society’s energy consumption. Solar radiation is an abundant and renewable energy source which can be harvested by solar collectors and used to cover heating demands in the built environment....... The seasonal availability of solar energy does however not match with the heating demands in buildings which typically are large in winter periods when limited solar energy is available. Heat can be stored over a few days in water stores but continuous heat losses limits the storage periods. The possibility...... of storing heat from summer where solar energy is widely available to winter periods where the heating demands are large, allows for implementing more renewable energy in our energy system. The phase change material (PCM) sodium acetate trihydrate (SAT) melts at 58 °C. The melting process requires...

  12. Heat pumps in combined heat and power systems

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

    2014-01-01

    Heat pumps have previously been proposed as a way to integrate higher amounts of renewable energy in DH (district heating) networks by integrating, e.g., wind power. The paper identifies and compares five generic configurations of heat pumps in DH systems. The operational performance...... of the considered cases. When considering a case where the heat pump is located at a CHP (combined heat and power) plant, a configuration that increases the DH return temperature proposes the lowest operation cost, as low as 12 EUR MWh-1 for a 90 °C e 40 °C DH network. Considering the volumetric heating capacity......, a third configuration is superior in all cases. Finally, the three most promising heat pump configurations are integrated in a modified PQ-diagram of the CHP plant. Each show individual advantages, and for two, also disadvantages in order to achieve flexible operation....

  13. Solar-powered Rankine heat pump for heating and cooling

    Science.gov (United States)

    Rousseau, J.

    1978-01-01

    The design, operation and performance of a familyy of solar heating and cooling systems are discussed. The systems feature a reversible heat pump operating with R-11 as the working fluid and using a motor-driven centrifugal compressor. In the cooling mode, solar energy provides the heat source for a Rankine power loop. The system is operational with heat source temperatures ranging from 155 to 220 F; the estimated coefficient of performance is 0.7. In the heating mode, the vapor-cycle heat pump processes solar energy collected at low temperatures (40 to 80 F). The speed of the compressor can be adjusted so that the heat pump capacity matches the load, allowing a seasonal coefficient of performance of about 8 to be attained.

  14. A Prototype Flux-Plate Heat-Flow Sensor for Venus Surface Heat-Flow Determinations

    Science.gov (United States)

    Morgan, Paul; Reyes, Celso; Smrekar, Suzanne E.

    2005-01-01

    Venus is the most Earth-like planet in the Solar System in terms of size, and the densities of the two planets are almost identical when selfcompression of the two planets is taken into account. Venus is the closest planet to Earth, and the simplest interpretation of their similar densities is that their bulk compositions are almost identical. Models of the thermal evolution of Venus predict interior temperatures very similar to those indicated for the regions of Earth subject to solid-state convection, but even global analyses of the coarse Pioneer Venus elevation data suggest Venus does not lose heat by the same primary heat loss mechanism as Earth, i.e., seafloor spreading. The comparative paucity of impact craters on Venus has been interpreted as evidence for relatively recent resurfacing of the planet associated with widespread volcanic and tectonic activity. The difference in the gross tectonic styles of Venus and Earth, and the origins of some of the enigmatic volcano-tectonic features on Venus, such as the coronae, appear to be intrinsically related to Venus heat loss mechanism(s). An important parameter in understanding Venus geological evolution, therefore, is its present surface heat flow. Before the complications of survival in the hostile Venus surface environment were tackled, a prototype fluxplate heat-flow sensor was built and tested for use under synthetic stable terrestrial surface conditions. The design parameters for this prototype were that it should operate on a conforming (sand) surface, with a small, self-contained power and recording system, capable of operating without servicing for at least several days. The precision and accuracy of the system should be < 5 mW/sq m. Additional information is included in the original extended abstract.

  15. Reflexive Aero Structures for Enhanced Survivability Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group Inc. (CRG) proposes to develop an advanced reflexive structure system to increase the survivability of aerostructures. This reflexive...

  16. Surviving severe traumatic brain injury in Denmark

    DEFF Research Database (Denmark)

    Odgaard, Lene; Poulsen, Ingrid; Kammersgaard, Lars Peter

    2015-01-01

    PURPOSE: To identify all hospitalized patients surviving severe traumatic brain injury (TBI) in Denmark and to compare these patients to TBI patients admitted to highly specialized rehabilitation (HS-rehabilitation). PATIENTS AND METHODS: Patients surviving severe TBI were identified from...... severe TBI were admitted to HS-rehabilitation. Female sex, older age, and non-working status pre-injury were independent predictors of no HS-rehabilitation among patients surviving severe TBI. CONCLUSION: The incidence rate of hospitalized patients surviving severe TBI was stable in Denmark...

  17. Reflexive Aero Structures for Enhanced Survivability Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group Inc. (CRG) will develop an advanced reflexive structure technology system to increase the survivability of future systems constructed of...

  18. Flow and heat transfer enhancement in tube heat exchangers

    Science.gov (United States)

    Sayed Ahmed, Sayed Ahmed E.; Mesalhy, Osama M.; Abdelatief, Mohamed A.

    2015-11-01

    The performance of heat exchangers can be improved to perform a certain heat-transfer duty by heat transfer enhancement techniques. Enhancement techniques can be divided into two categories: passive and active. Active methods require external power, such as electric or acoustic field, mechanical devices, or surface vibration, whereas passive methods do not require external power but make use of a special surface geometry or fluid additive which cause heat transfer enhancement. The majority of commercially interesting enhancement techniques are passive ones. This paper presents a review of published works on the characteristics of heat transfer and flow in finned tube heat exchangers of the existing patterns. The review considers plain, louvered, slit, wavy, annular, longitudinal, and serrated fins. This review can be indicated by the status of the research in this area which is important. The comparison of finned tubes heat exchangers shows that those with slit, plain, and wavy finned tubes have the highest values of area goodness factor while the heat exchanger with annular fin shows the lowest. A better heat transfer coefficient ha is found for a heat exchanger with louvered finned and thus should be regarded as the most efficient one, at fixed pumping power per heat transfer area. This study points out that although numerous studies have been conducted on the characteristics of flow and heat transfer in round, elliptical, and flat tubes, studies on some types of streamlined-tubes shapes are limited, especially on wing-shaped tubes (Sayed Ahmed et al. in Heat Mass Transf 50: 1091-1102, 2014; in Heat Mass Transf 51: 1001-1016, 2015). It is recommended that further detailed studies via numerical simulations and/or experimental investigations should be carried out, in the future, to put further insight to these fin designs.

  19. Improving Survival in Decompensated Cirrhosis

    Directory of Open Access Journals (Sweden)

    Amar Nath Mukerji

    2012-01-01

    Full Text Available Mortality in cirrhosis is consequent of decompensation, only treatment being timely liver transplantation. Organ allocation is prioritized for the sickest patients based on Model for End Stage Liver Disease (MELD score. In order to improve survival in patients with high MELD score it is imperative to preserve them in suitable condition till transplantation. Here we examine means to prolong life in high MELD score patients till a suitable liver is available. We specially emphasize protection of airways by avoidance of sedatives, avoidance of Bilevel Positive Airway Pressure, elective intubation in grade III or higher encephalopathy, maintaining a low threshold for intubation with lesser grades of encephalopathy when undergoing upper endoscopy or colonoscopy as pre transplant evaluation or transferring patient to a transplant center. Consider post-pyloric tube feeding in encephalopathy to maintain muscle mass and minimize risk of aspiration. In non intubated and well controlled encephalopathy, frequent physical mobility by active and passive exercises are recommended. When renal replacement therapy is needed, night-time Continuous Veno-Venous Hemodialysis may be useful in keeping the daytime free for mobility. Sparing and judicious use of steroids needs to be borne in mind in treatment of ARDS and acute hepatitis from alcohol or autoimmune process.

  20. Modeling the airborne survival of influenza virus in a residential setting: the impacts of home humidification

    Directory of Open Access Journals (Sweden)

    Myatt Theodore A

    2010-09-01

    Full Text Available Abstract Background Laboratory research studies indicate that aerosolized influenza viruses survive for longer periods at low relative humidity (RH conditions. Further analysis has shown that absolute humidity (AH may be an improved predictor of virus survival in the environment. Maintaining airborne moisture levels that reduce survival of the virus in the air and on surfaces could be another tool for managing public health risks of influenza. Methods A multi-zone indoor air quality model was used to evaluate the ability of portable humidifiers to control moisture content of the air and the potential related benefit of decreasing survival of influenza viruses in single-family residences. We modeled indoor AH and influenza virus concentrations during winter months (Northeast US using the CONTAM multi-zone indoor air quality model. A two-story residential template was used under two different ventilation conditions - forced hot air and radiant heating. Humidity was evaluated on a room-specific and whole house basis. Estimates of emission rates for influenza virus were particle-size specific and derived from published studies and included emissions during both tidal breathing and coughing events. The survival of the influenza virus was determined based on the established relationship between AH and virus survival. Results The presence of a portable humidifier with an output of 0.16 kg water per hour in the bedroom resulted in an increase in median sleeping hours AH/RH levels of 11 to 19% compared to periods without a humidifier present. The associated percent decrease in influenza virus survival was 17.5 - 31.6%. Distribution of water vapor through a residence was estimated to yield 3 to 12% increases in AH/RH and 7.8-13.9% reductions in influenza virus survival. Conclusion This modeling analysis demonstrates the potential benefit of portable residential humidifiers in reducing the survival of aerosolized influenza virus by controlling humidity

  1. Heat pumps for the home

    CERN Document Server

    Cantor, John

    2013-01-01

    In recent years, heat pumps have emerged as a promising new form of technology with a relatively low environmental impact. Moreover, they have presented householders with an opportunity to reduce their heating bills. Heat pumps can heat a building by 'pumping' heat from either the ground or the air outside: an intriguing process which utilizes principles that are somewhat analogous to those employed in the domestic refrigerator. Armed with the practical information contained in these pages, homeowners will have the necessary knowledge to take advantage of this potentially low-carbon t

  2. Economical noise- and heat insulation

    Energy Technology Data Exchange (ETDEWEB)

    1982-06-01

    All noise protection and heat insulations measures are interlinked. While noise abatement and insulation is primarily a task of health protection, the economically optimised heat insulation is rather a problem for financial mathematics. Parameters, influencing the heat insulation are subject to changes which will affect the profitability of heat insulation measures in turn. Several options for reducing the noise level are described and some standard values for material cost are supplied. Depending on the kind of noise different abatement methods are suitable which require materials with specific properties. Measures for heat insulation are described which to a great extent are identical will noise abatement measures.

  3. Measuring of heat transfer coefficient

    DEFF Research Database (Denmark)

    Henningsen, Poul; Lindegren, Maria

    Subtask 3.4 Measuring of heat transfer coefficient Subtask 3.4.1 Design and setting up of tests to measure heat transfer coefficient Objective: Complementary testing methods together with the relevant experimental equipment are to be designed by the two partners involved in order to measure...... the heat transfer coefficient for a wide range of interface conditions in hot and warm forging processes. Subtask 3.4.2 Measurement of heat transfer coefficient The objective of subtask 3.4.2 is to determine heat transfer values for different interface conditions reflecting those typically operating in hot...

  4. Absorption-heat-pump system

    Science.gov (United States)

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  5. Residential CO{sub 2} heat pump system for combined space heating and hot water heating

    Energy Technology Data Exchange (ETDEWEB)

    Stene, Joern

    2004-02-01

    Carbon dioxide (CO{sub 2}, R-744) has been identified as a promising alternative to conventional working fluids in a number of applications due to its favourable environmental and thermophysical properties. Previous work on residential CO{sub 2} heat pumps has been dealing with systems for either space heating or hot water heating, and it was therefore considered interesting to carry out a theoretical and experimental study of residential CO{sub 2} heat pump systems for combined space heating and hot water heating - o-called integrated CO{sub 2} heat pump systems. The scope of this thesis is limited to brine-to-water and water-to-water heat pumps connected to low-temperature hydronic space heating systems. The main conclusions are: (1) Under certain conditions residential CO{sub 2} heat pump systems for combined space heating and hot water heating may achieve the same or higher seasonal performance factor (SPF) than the most energy efficient state-of-the-art brine-to-water heat pumps. (2) In contrary to conventional heat pump systems for combined space heating and DHW heating, the integrated CO{sub 2} heat pump system achieves the highest COP in the combined heating mode and the DHW heating mode, and the lowest COP in the space heating mode. Hence, the larger the annual DHW heating demand, the higher the SPF of the integrated CO{sub 2} heat pump system. (3) The lower the return temperature in the space heating system and the lower the DHW storage temperature, the higher the COP of the integrated CO{sub 2} heat pump. A low return temperature in the space heating system also results in a moderate DHW heating capacity ratio, which means that a relatively large part of the annual space heating demand can be covered by operation in the combined heating mode, where the COP is considerably higher than in the space heating mode. (4) During operation in the combined heating mode and the DHW heating mode, the COP of the integrated CO{sub 2} heat pump is heavily influenced by

  6. Next Generation Microchannel Heat Exchangers

    CERN Document Server

    Ohadi, Michael; Dessiatoun, Serguei; Cetegen, Edvin

    2013-01-01

    In Next Generation Microchannel Heat Exchangers, the authors’ focus on the new generation highly efficient heat exchangers and presentation of novel data and technical expertise not available in the open literature.  Next generation micro channels offer record high heat transfer coefficients with pressure drops much less than conventional micro channel heat exchangers. These inherent features promise fast penetration into many mew markets, including high heat flux cooling of electronics, waste heat recovery and energy efficiency enhancement applications, alternative energy systems, as well as applications in mass exchangers and chemical reactor systems. The combination of up to the minute research findings and technical know-how make this book very timely as the search for high performance heat and mass exchangers that can cut costs in materials consumption intensifies.

  7. Realiability Of Heat Supply Subsystem

    Directory of Open Access Journals (Sweden)

    Babiarz Bożena

    2015-11-01

    Full Text Available The article presents the reliability analysis of subsystem of heat supply in the example of 47 thousand inhabitants’ city. The analysis was made on the basis of operational data made available by the Municipal Heating Company, between the years 2001 ÷ 2012. To describe the quantitative reliability of heat supply subsystem reliability indicators are used. Main times between failure and unitary failure rates including the month of their occurrence, type and diameter of the heating network, thermal power region were working out. Knowing the characteristics of the time to repair for the heating network, the reliability of heat supply subsystem for different thermal power region, considering the district heating system configuration can be determined.

  8. Chapter 12. Space Heating Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, Kevin D.

    1998-01-01

    The performance evaluation of space heating equipment for a geothermal application is generally considered from either of two perspectives: (a) selecting equipment for installation in new construction, or (b) evaluating the performance and retrofit requirements of an existing system. With regard to new construction, the procedure is relatively straightforward. Once the heating requirements are determined, the process need only involve the selection of appropriately sized hot water heating equipment based on the available water temperature. It is important to remember that space heating equipment for geothermal applications is the same equipment used in non-geothermal applications. What makes geothermal applications unique is that the equipment is generally applied at temperatures and flow rates that depart significantly from traditional heating system design. This chapter presents general considerations for the performance of heating equipment at non-standard temperature and flow conditions, retrofit of existing systems, and aspects of domestic hot water heating.

  9. Salmonella Typhimurium, Infantis, Derby, and Enteritidis survival in pasty dulce de leche

    OpenAIRE

    Silveira,Débora Rodrigues da; Lopes,Nathalie Almeida; Gonzalez,Helenice de Lima; Timm,Cláudio Dias

    2012-01-01

    Dulce de leche is a food obtained by concentration and heating of milk with the addition of sucrose. The common practice of opening the dulce de leche containers in retail markets can lead to food contamination by Salmonella. The objective of this study was to evaluate the survivability of Salmonellaenterica subsp. enterica serotypes Typhimurium, Enteritidis, Infantis and Derby in pasty dulce de leche. Aliquots of this sweet were experimentally contaminated with these microorganisms and later...

  10. Cryogenic regenerative heat exchangers

    CERN Document Server

    Ackermann, Robert A

    1997-01-01

    An in-depth survey of regenerative heat exchangers, this book chronicles the development and recent commercialization of regenerative devices for cryogenic applications. Chapters cover historical background, concepts, practical applications, design data, and numerical solutions, providing the latest information for engineers to develop advanced cryogenic machines. The discussions include insights into the operation of a regenerator; descriptions of the cyclic and fluid temperature distributions in a regenerator; data for various matrix geometries and materials, including coarse and fine bronze, stainless steel-woven wire mesh screens, and lead spheres; and unique operating features of cryocoolers that produce deviations from ideal regenerator theory.

  11. Engineering heat transfer

    CERN Document Server

    Annaratone, Donatello

    2010-01-01

    This book is a generalist textbook; it is designed for anybody interested in heat transmission, including scholars, designers and students. Two criteria constitute the foundation of Annaratone's books, including the present one. The first one consists of indispensable scientific rigor without theoretical exasperation. The inclusion in the book of some theoretical studies, even if admirable for their scientific rigor, would have strengthened the scientific foundation of this publication, yet without providing the reader with further applicable know-how. The second criterion is to deliver practi

  12. Theory of heat

    CERN Document Server

    Maxwell, James Clerk

    2001-01-01

    Though James Clerk Maxwell (1831-1879) is best remembered for his epochal achievements in electricity and magnetism, he was wide-ranging in his scientific investigations, and he came to brilliant conclusions in virtually all of them. As James R. Newman put it, Maxwell ""combined a profound physical intuition, an exquisite feeling for the relationship of objects, with a formidable mathematical capacity to establish orderly connections among diverse phenomena. This blending of the concrete and the abstract was the chief characteristic of almost all his researches.""Maxwell's work on heat and st

  13. Heat transfer characteristics of various kinds of ground heat exchangers for ground source heat pump system

    Science.gov (United States)

    Miyara, A.; Kariya, K.; Ali, Md. H.; Selamat, S. B.; Jalaluddin

    2017-01-01

    Three kinds of vertical-type ground heat exchangers, U-tube; double-tube; multi-tube, and two kinds of horizontal-type ground heat exchangers, standing Slinky; reclined Slinky, were experimentally and numerically investigated in order to clarify their heat transfer characteristics. Experiments and simulations were carried out under two operation conditions which are continuous operation mode and discontinuous operation mode and effects of temperature recovery and thermal storage on the heat transfer rate were shown. Differences of the heat transfer rate between standing Slinky and reclined Slinky were also indicated.

  14. Heat Emission from a Burning Cigarette

    Directory of Open Access Journals (Sweden)

    Miura K

    2014-12-01

    Full Text Available We investigated the relationship between the smoldering burn rate and the heat transfer from a burning cigarette by measuring the heat emitted by radiation and convection, separately. The net heat generated and the net heat emitted by a burning cigarette did not vary with a change of the cigarette smoldering burn rate. The total heat emitted from a statically burning cigarette was about 50% of the total combustion heat. About 50% of the heat emitted was released as radiation heat. The smoldering burn rate did not affect the total amount of heat emitted nor the ratio of radiated heat to convected heat.

  15. Survival From Childhood Hematological Malignancies in Denmark

    DEFF Research Database (Denmark)

    Erdmann, Friederike; Winther, Jeanette Falck; Dalton, Susanne Oksbjerg

    2016-01-01

    .76 (CI 2.01; 16.51) were observed for the fourth or later born children with ALL (N = 41) and AML (N = 9), respectively. Children with older parents showed a tendency toward inferior ALL survival, while for AML young maternal age was related to poorer survival. Based on small numbers, a trend toward...

  16. Zimbabwe's Exodus: Crisis, Migration, Survival | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-07-01

    Zimbabwe's Exodus: Crisis, Migration, Survival. Book cover Zimbabwe's Exodus: Crisis, Migration, Survival. Editor(s):. Jonathan Crush and Daniel Tevera. Publisher(s):. Southern African Migration Programme, IDRC. July 1, 2010. ISBN: 9781920409227. 420 pages. e-ISBN: 9781552504994. Download PDF · Read the e- ...

  17. Domesticating Ugandan local earthworms: Survival of African ...

    African Journals Online (AJOL)

    3.5; E, 90±2.8 and E. eugeniae There was significant effect (P<0.05) of feeding rate on the survival of both species and the Fisher's LSD multiple comparison test also showed significant different (P<0.05) in the survival among the two species.

  18. Cancer rehabilitation: a barometer for survival?

    Science.gov (United States)

    Saotome, Takako; Klein, Linda; Faux, Steven

    2015-10-01

    This pilot study was conducted to describe the clinical features and functional outcomes of patients attending inpatient rehabilitation for cancer-related deconditioning and neurological deficits and to explore factors associated with improved survival. Using a retrospective audit, demographic characteristics, discharge outcomes, survival time, and functional status as measured by Functional Independence Measure (FIM) were recorded for 73 patients. Clinical status was estimated by Karnofsky Performance Status Scale (KPS). Cox regression was used to assess factors associated with improved survival following discharge from rehabilitation. Significant functional gains following rehabilitation were observed in total FIM (p = 0.02), motor FIM (p = 0.001), and KPS (p = 0.003). Length of survival ranged from 9.0 to 25.0 months, with 26 cases surviving to the end of study (censored). Patients scoring a total FIM of ≥80 survived significantly longer than patients scoring <80 (p = 0.002). At discharge, motor FIM scores (p = 0.004), FIM Efficiency (p = 0.001), KPS scores (p = 0.022), ambulation ability (p = 0.026), return to home (p = 0.009), and receipt of in-home services (p = 0.045) were significantly associated with improved survival. Functional improvement achieved through inpatient rehabilitation was associated with prolonged survival among cancer patients. Rehabilitation leading to improved independence among cancer patients may act as a marker of those with greater likelihood of better prognosis.

  19. Nematode survival in relation to soil moisture

    NARCIS (Netherlands)

    Simons, W.R.

    1973-01-01

    Established nematode populations are very persistent in the soil. It is known that they need sufficient soil moisture for movement, feeding and reproduction (fig. 5), and that there are adverse soil moisture conditions which they cannot survive. The influence of soil moisture on survival

  20. Socioeconomic position and survival after cervical cancer

    DEFF Research Database (Denmark)

    Ibfelt, E H; Kjær, S K; Høgdall, C

    2013-01-01

    In an attempt to decrease social disparities in cancer survival, it is important to consider the mechanisms by which socioeconomic position influences cancer prognosis. We aimed to investigate whether any associations between socioeconomic factors and survival after cervical cancer could...... be explained by socioeconomic differences in cancer stage, comorbidity, lifestyle factors or treatment....

  1. MECHANICAL TRANSMISSION AND SURVIVAL OF BACTERIAL ...

    African Journals Online (AJOL)

    jen

    The transmission of enset bacterial wilt with contaminated knives and the survival of the causal agent in soil and enset plant debris was studied ... Xanthomonas campestris pv. musacearum (Xcm) isolates were observed to survive in the soil up to. 9 days. Thereafter the .... and needle, while pathogenicity tests were carried ...

  2. Long-term survival in Patau syndrome.

    Science.gov (United States)

    Tunca, Y; Kadandale, J S; Pivnick, E K

    2001-04-01

    A female patient with an extra chromosome 13 (Patau syndrome) is described. There are only five previous reports of patients with trisomy 13 who have survived past the first decade. It is concluded that non-lethal congenital anomalies and aggressive medical care play an important role in the survival of patients with trisomy 13.

  3. EFFECT OF SALINITY ON SURVIVAL AND LARVAL ...

    African Journals Online (AJOL)

    Laboratory investigations was conducted to gain a better insight into the effect of changing salinity regime on the development and survival of Macrobrachium vollenhoveli larvae. At water temperature of 28 ± 2oC, larvae reared in the salinity range of 0 to 10 ppt showed low survival (<48%), whereas those reared at 12 ...

  4. Escherichia coli survival in waters: Temperature dependence

    Science.gov (United States)

    Knowing the survival rates of water-borne Escherichia coli is important in evaluating microbial contamination and making appropriate management decisions. E. coli survival rates are dependent on temperature, a dependency that is routinely expressed using an analogue of the Q10 mo...

  5. Relief for surviving relatives following a suicide.

    NARCIS (Netherlands)

    Oud, MJT; de Groot, MH

    2006-01-01

    Relief for surviving relatives following a suicide. - After the suicide of a 43-year-old woman with known depression, a 41-year-old paraplegic man who recently developed diarrhoea and a 41-year-old woman with probable depression with symptoms of psychosis, the general practitioners of the surviving

  6. Survival after in-hospital Cardiopulmonary Resuscitation

    Directory of Open Access Journals (Sweden)

    M Adib Hajbaghery

    2005-05-01

    Full Text Available Background: During recent years, cardiopulmonary resuscitation (CPR in hospital has received much attention. However, the survival rate of CPR in Iran’s hospitals is unknown. This study was designed to evaluate outcome of in-hospital CPR in Kashan. Methods: A longitudinal case registry study was conducted on all cases of in-hospital CPR during 6 months at 2002. Necessary data including; age, sex, underlying disease, working shift, time from cardiac arrest until initiating of CPR and until defibrillation, duration and result of CPR, frequency of tracheal intubations and time served for it were collected in a checklist. Results: In six months study, 206 cases of cardiopulmonary resuscitation attempted. The survival rate was similar for both sexes. Short-term survival observed in19.9% of cases and only 5.3% survived to discharge. Conclusions: Duration of CPR, time of the first defibrillation, response time and the location of cardiac arrest are the key predictors of survival to hospital discharge and in-hospital CPR strategies require improvement. This study promotes a national study on post CPR survival for accurate data on our performance in attention to chain of survival. KeyWords: Cardiopulmonary Resuscitation (CPR, Survival rate, Iran

  7. Racial differences in survival from gynecologic cancer.

    Science.gov (United States)

    Morgan, M A; Behbakht, K; Benjamin, I; Berlin, M; King, S A; Rubin, S C

    1996-12-01

    To determine whether survival from gynecologic cancer is different between African-American and white patients at an inner-city hospital with both a large clinic and a private service. We studied 538 patients (89 African American, 449 white) diagnosed with cervical, uterine, or ovarian cancer at a single institution from January 1, 1989 through December 31, 1993. Information was obtained on age, stage, site of disease, histology, and type of health insurance (public or commercial). Insurance coverage was used as a proxy for socioeconomic status. Overall survival was estimated by the method of Kaplan and Meier and compared by the log-rank test. Cox proportional hazard modeling was used to evaluate the effects of multiple factors on survival. African-American patients were significantly older and were more likely to have cervical cancer and public insurance than white patients. Overall survival was worse for African-American patients than for white patients (P whites, and African-American patients older than 65 years had a worse survival than whites of similar age. On multivariate analysis, only stage and insurance coverage were significant predictors of survival. African-American patients with gynecologic cancer at our institution have worse overall survival than white patients. The survival difference seems to be due predominantly to differences in socioeconomic status and stage at diagnosis.

  8. Responses Of Subalpine Conifer Seedling Germination And Survival To Soil Microclimate In The Alpine Treeline Warming Experiment

    Science.gov (United States)

    Castanha, C.; Moyes, A. B.; Torn, M. S.; Germino, M. J.; Kueppers, L. M.

    2011-12-01

    At Niwot Ridge, Colorado, we used common gardens and climate manipulations to investigate potential subalpine tree species range shifts due to climate change. In Fall 2009 we harvested seed from local populations of limber pine and Englemann spruce, which we sowed in 3 experimental sites spanning an elevation gradient from lower subalpine forest (3080m asl), to the upper subalpine treeline ecotone (3400m asl), to the alpine tundra (3550m asl). In October we turned on overhead infrared heaters designed to increase growing season surface soil temperature by 4-5°C, and following snowmelt in 2010 we crossed this heating treatment with manual watering, adding 3mm of water each week. Here we report on the species, site, and treatment effects on seedling emergence and survival as mediated by snowmelt date, soil temperature, and soil moisture. Depending on the site and plot, heating accelerated germination by 1 to 4 weeks. Germination degree days (heat accumulation required for seed germination) were greater for pine than for spruce and greater in drier plots. Seedling survival was explained by date of emergence, with older seedlings more likely to survive the season. Survival was also explained by drought degree days -- the number of days below critical soil moisture thresholds compounded by high temperature -- with lower thresholds for spruce than for pine. Our preliminary results indicate that a warmer environment will stimulate germination for both species, but that, survival - especially for spruce - will be critically modulated by summer soil moisture.

  9. Heat Emission from a Burning Cigarette

    OpenAIRE

    Miura K; Nagao A; Ueyama K

    2014-01-01

    We investigated the relationship between the smoldering burn rate and the heat transfer from a burning cigarette by measuring the heat emitted by radiation and convection, separately. The net heat generated and the net heat emitted by a burning cigarette did not vary with a change of the cigarette smoldering burn rate. The total heat emitted from a statically burning cigarette was about 50% of the total combustion heat. About 50% of the heat emitted was released as radiation heat. The smolder...

  10. Microbial survival and odor in laundry

    DEFF Research Database (Denmark)

    Jepsen, Signe Munk; Johansen, Charlotte; Stahnke, Louise Heller

    2001-01-01

    , hydrophobic odorants [(Z)-4- heptenal, (E)-2-nonenal, and guaiacol] adhered more strongly to polyester than the acids. The odor formed by surviving skin microflora attached to textiles soiled with human sebum and sweat after laundering at 30 degreesC was studied by sensory evaluation and aroma extract......-were evaluated on cotton textile. A significant survival and transfer between textiles were found for all four test strains washed in E.U. and U.S. color detergents (without bleach), whereas no survival was observed in bleach-containing detergents. Gram-negative strains generally survived in greater numbers than...... Gram-positive strains. A greater survival was observed in U.S. detergents at U.S. conditions (30 degreesC, 12 min) than in E.U. detergents at E.U. conditions (40 degreesC, 30 min). The adhesion of odorants to cotton and polyester textiles during washing and drying was studied using six previously...

  11. Thermodynamics and heat power

    CERN Document Server

    Granet, Irving

    2014-01-01

    Fundamental ConceptsIntroductionThermodynamic SystemsTemperatureForce and MassElementary Kinetic Theory of GasesPressureReviewKey TermsEquations Developed in This ChapterQuestionsProblemsWork, Energy, and HeatIntroductionWorkEnergyInternal EnergyPotential EnergyKinetic EnergyHeatFlow WorkNonflow WorkReviewKey TermsEquations Developed in This ChapterQuestionsProblemsFirst Law of ThermodynamicsIntroductionFirst Law of ThermodynamicsNonflow SystemSteady-Flow SystemApplications of First Law of ThermodynamicsReviewKey TermsEquations Developed in This ChapterQuestionsProblemsThe Second Law of ThermodynamicsIntroductionReversibility-Second Law of ThermodynamicsThe Carnot CycleEntropyReviewKey TermsEquations Developed in This ChapterQuestionsProblemsProperties of Liquids and GasesIntroductionLiquids and VaporsThermodynamic Properties of SteamComputerized PropertiesThermodynamic DiagramsProcessesReviewKey TermsEquations Developed in This ChapterQuestionsProblemsThe Ideal GasIntroductionBasic ConsiderationsSpecific Hea...

  12. Heat pipe turbine vane cooling

    Energy Technology Data Exchange (ETDEWEB)

    Langston, L.; Faghri, A. [Univ. of Connecticut, Storrs, CT (United States)

    1995-10-01

    The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high heat transfer rate and an uniform temperature along the vane due to the internal change of phase of the heat pipe working fluid. Furthermore, this technology can also eliminate hot spots at the vane leading and trailing edges and increase the vane life by preventing thermal fatigue cracking. There is also the possibility of requiring no bleed air from the compressor, and therefore eliminating engine performance losses resulting from the diversion of compressor discharge air. Significant improvement in gas turbine performance can be achieved by using heat pipe technology in place of conventional air cooled vanes. A detailed numerical analysis of a heat pipe vane will be made and an experimental model will be designed in the first year of this new program.

  13. High Temperature Thermoacoustic Heat Pump

    Energy Technology Data Exchange (ETDEWEB)

    Tijani, H.; Spoelstra, S. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2012-07-15

    Thermoacoustic technology can provide new types of heat pumps that can be deployed in different applications. Thermoacoustic heat pumps can for example be applied in dwellings to generate cooling or heating. Typically, space and water heating makes up about 60% of domestic and office energy consumption. The application of heat pumps can contribute to achieve energy savings and environmental benefits by reducing CO2 and NOx emissions. This paper presents the study of a laboratory scale thermoacoustic-Stirling heat pump operating between 10C and 80C which can be applied in domestics and offices. The heat pump is driven by a thermoacoustic-Stirling engine. The experimental results show that the heat pump pumps 250 W of heat at 60C at a drive ratio of 3.6 % and 200 W at 80C at a drive ratio of 3.5 %. The performance for both cases is about 40% of the Carnot performance. The design, construction, and performance measurements of the heat pump will be presented and discussed.

  14. Residential Variable-Capacity Heat Pumps Sized to Heating Loads

    Energy Technology Data Exchange (ETDEWEB)

    Munk, Jeffrey D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jackson, Roderick K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Odukomaiya, Adewale [Georgia Inst. of Technology, Atlanta, GA (United States); Gehl, Anthony C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-01-01

    Variable capacity heat pumps are an emerging technology offering significant energy savings potential and improved efficiency. With conventional single-speed systems, it is important to appropriately size heat pumps for the cooling load as over-sizing would result in cycling and insufficient latent capacity required for humidity control. These appropriately sized systems are often under-sized for the heating load and require inefficient supplemental electric resistance heat to meet the heating demand. Variable capacity heat pumps address these shortcomings by providing an opportunity to intentionally size systems for the dominant heating season load without adverse effects of cycling or insufficient dehumidification in the cooling season. This intentionally-sized system could result in significant energy savings in the heating season, as the need for inefficient supplemental electric resistance heat is drastically reduced. This is a continuation of a study evaluating the energy consumption of variable capacity heat pumps installed in two unoccupied research homes in Farragut, a suburb of Knoxville, Tennessee. In this particular study, space conditioning systems are intentionally sized for the heating season loads to provide an opportunity to understand and evaluate the impact this would have on electric resistance heat use and dehumidification. The results and conclusions drawn through this research are valid and specific for portions of the Southeastern and Midwestern United States falling in the mixed-humid climate zone. While other regions in the U.S. do not experience this type of climate, this work provides a basis for, and can help understand the implications of other climate zones on residential space conditioning energy consumption. The data presented here will provide a framework for fine tuning residential building EnergyPlus models that are being developed.

  15. Heat capacity and heat of dissociation of methane hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Rueff, R.M.; Sloan, E.D.; Yesavage, V.F.

    1988-09-01

    The objective of this study was to determine the heat capacity and heat of dissociation of methane hydrates. A technique has been devised which circumvents the two major problems encountered in measuring gas hydrate heat capacity: the need to impose a mechanical pressure during the measurement and the need to have an absolutely pure hydrate sample. The technique was shown to be successful utilizing high-pressure, constant-volume cells in a differential scanning calorimeter.

  16. Seasonal survival of adult female mottled ducks

    Science.gov (United States)

    Moon, Jena A.; Haukos, David A.; Conway, Warren C.

    2017-01-01

    The mottled duck (Anas fulgivula) is a non-migratory duck dependent on coastal habitats to meet all of its life cycle requirements in the Western Gulf Coast (WGC) of Texas and Louisiana, USA. This population of mottled ducks has experienced a moderate decline during the past 2 decades. Adult survival has been identified as an important factor influencing population demography. Previous work based on band-recovery data has provided only annual estimates of survival. We assessed seasonal patterns of female mottled duck survival from 2009 to 2012 using individuals marked with satellite platform transmitter terminals (PTTs). We used temperature and movement sensors within each PTT to indicate potential mortality events. We estimated cumulative weekly survival and ranked factors influential in patterns of mortality using known-fate modeling in Program MARK. Models included 4 predictors: week; hunting and non-hunting periods; biological periods defined as breeding, brooding, molt, and pairing; and mass at time of capture. Models containing hunt periods, during and outside the mottled duck season, comprised essentially 100% of model weights where both legal and illegal harvest had a negative influence on mottled duck survival. Survival rates were low during 2009–2011 (12–38% annual rate of survival), when compared with the long-term banding average of 53% annual survival. During 2011, survival of female mottled ducks was the lowest annual rate (12%) ever documented and coincided with extreme drought. Management actions maximizing the availability of wetlands and associated upland habitats during hunting seasons and drought conditions may increase adult female mottled duck survival.

  17. Heat pump having improved defrost system

    Science.gov (United States)

    Chen, Fang C.; Mei, Viung C.; Murphy, Richard W.

    1998-01-01

    A heat pump system includes, in an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant: a compressor; an interior heat exchanger; an exterior heat exchanger; an accumulator; and means for heating the accumulator in order to defrost the exterior heat exchanger.

  18. Magnetic Heat Pump Containing Flow Diverters

    Science.gov (United States)

    Howard, Frank S.

    1995-01-01

    Proposed magnetic heat pump contains flow diverters for suppression of undesired flows. If left unchecked, undesired flows mix substantial amounts of partially heated and partially cooled portions of working fluid, effectively causing leakage of heat from heated side to cooled side. By reducing leakage of heat, flow diverters increase energy efficiency of magnetic heat pump, potentially offering efficiency greater than compressor-driven refrigerator.

  19. Hybrid Heat Pipes for High Heat Flux Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The thermal transport requirements for future spacecraft missions continue to increase, approaching several kilowatts. At the same time the heat acquisition areas...

  20. Design manual. [High temperature heat pump for heat recovery system

    Energy Technology Data Exchange (ETDEWEB)

    Burch, T.E.; Chancellor, P.D.; Dyer, D.F.; Maples, G.

    1980-01-01

    The design and performance of a waste heat recovery system which utilizes a high temperature heat pump and which is intended for use in those industries incorporating indirect drying processes are described. It is estimated that use of this heat recovery system in the paper, pulp, and textile industries in the US could save 3.9 x 10/sup 14/ Btu/yr. Information is included on over all and component design for the heat pump system, comparison of prime movers for powering the compressor, control equipment, and system economics. (LCL)

  1. Heat pipe heat rejection system. [for electrical batteries

    Science.gov (United States)

    Kroliczek, E. J.

    1976-01-01

    A prototype of a battery heat rejection system was developed which uses heat pipes for more efficient heat removal and for temperature control of the cells. The package consists of five thermal mock-ups of 100 amp-hr prismatic cells. Highly conductive spacers fabricated from honeycomb panels into which heat pipes are embedded transport the heat generated by the cells to the edge of the battery. From there it can be either rejected directly to a cold plate or the heat flow can be controlled by means of two variable conductance heat pipes. The thermal resistance between the interior of the cells and the directly attached cold plate was measured to be 0.08 F/Watt for the 5-cell battery. Compared to a conductive aluminum spacer of equal weight the honeycomb/heat pipe spacer has approximately one-fifth of the thermal resistance. In addition, the honeycomb/heat pipe spacer virtually eliminates temperature gradients along the cells.

  2. Fragment Production and Survival in Irradiated Disks: A Comprehensive Cooling Criterion

    Science.gov (United States)

    Kratter, Kaitlin M.; Murray-Clay, Ruth A.

    2011-10-01

    Accretion disks that become gravitationally unstable can fragment into stellar or substellar companions. The formation and survival of these fragments depends on the precarious balance between self-gravity, internal pressure, tidal shearing, and rotation. Disk fragmentation depends on two key factors: (1) whether the disk can get to the fragmentation boundary of Q = 1 and (2) whether fragments can survive for many orbital periods. Previous work suggests that to reach Q = 1, and have fragments survive, a disk must cool on an orbital timescale. Here we show that disks heated primarily by external irradiation always satisfy the standard cooling time criterion. Thus, even though irradiation heats disks and makes them more stable in general, once they reach the fragmentation boundary, they fragment more easily. We derive a new cooling criterion that determines fragment survival and calculate a pressure-modified Hill radius, which sets the maximum size of pressure-supported objects in a Keplerian disk. We conclude that fragmentation in protostellar disks might occur at slightly smaller radii than previously thought and recommend tests for future simulations that will better predict the outcome of fragmentation in real disks.

  3. Heat savings in buildings in a 100% renewable heat and power system in Denmark with different shares of district heating

    DEFF Research Database (Denmark)

    Zvingilaite, Erika; Balyk, Olexandr

    2014-01-01

    . A further expansion of district heating network in Denmark is assessed and penetration of heat savings is analysed in this context.If all heat saving measures, included in the model, are implemented, heat demand in Danish buildings in 2050 could be reduced by around 40%. Results show that it is cost...... levels of heat savings, which can be implemented by reducing heat transmission losses through building elements and by installing ventilation systems with heat recovery, in different future Danish heat and power system scenarios. Today almost 50% of heat demand in Denmark is covered by district heating...

  4. Heat pump with freeze-up prevention

    Science.gov (United States)

    Ecker, Amir L.

    1981-01-01

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid prevents freeze up of the second heat exchanger by keeping the temperature above the dew point; and, optionally, provides heat for efficient operation.

  5. How and why to survive at Venus surface.

    Science.gov (United States)

    Ekonomov, A.

    2008-09-01

    To investigate rare and long lasting events on Venus such as seismicity or large scale atmospheric waves we need to use long lived lander ( LLL). There are meteorological and seismological instruments which survive at 500oC and 100 bar, but bottle neck is power supply and data acquisition system. Today we have no ready-made systems to fulfill this task. Lifetime of one venussian solar day (117 days) can be taken as start point for design of lightweight class lander .We propose basic LLL conception of two concentric rigid spheres with special high-temperature MLI in between and liquid water under ambient pressure inside as heat absorber. Thermal conductivity of MLI made of pure silver or gold foils in high vacuum is calculated. Thermodynamic effects of water: melting, heat capacitance in liquid phase , vaporization at 92 bar and 305 oC and superheating up to ambient temperature of 460oC are considered. In case of 0.4 m diameter and 40 kg water inside you are able to use common silicon electronics (200o C) for one month (even more if water was frozen before entry) and GaN (300oC) special electronics for more then three months after landing. Total mass will be 100 kg on surface and 150 kg before atmospheric entry. Our lightweight LLL conception is balanced and need not for dangerous and exotic components .

  6. Effect of Conditioning Treatments on the Survival of Radopholus similis at High Temperatures.

    Science.gov (United States)

    Arcinas, A; Sipes, B S; Hara, A H; Tsang, M M C

    2005-09-01

    Heat treatments are an environmentally safe method for eliminating quarantine pests from tropical foliage. Conditioning heat treatments can induce thermotolerance against subsequent and otherwise phytotoxic temperatures in tropical foliage, allowing heat treatments to be even more effective. However, if thermotolerance is also induced in nematodes of quarantine significance like Radopholus similis, heat treatments would be rendered ineffective. A lethal thermal death point (LT(99.9)) was established for R. similis by recording mortality at 25 (control temperature), 43 degrees C, 45 degrees C, 47 degrees C, or 49 degrees C after a 0, 1-, 2-, 4-, 6-, 8-, 10-, 12-, or 15-minute exposure. In a second experiment, nematodes were conditioned at 35, 40, or 45 degrees C for 0, 15, 30, 60, 120, and 180 minutes, allowed to rest for 3 hours, and then challenged at 47 degrees C for 5 minutes. No nematodes survived the challenge heat treatment; rather, nematode mortality was hastened by the conditioning treatment itself. In a third experiment, R. similis inside anthurium roots were conditioned at 25 degrees C or 40 degrees C for 15 minutes and then treated at 45 degrees C for up to 8 minutes. Mortality of conditioned and unconditioned nematodes was similar (P > 0.1). Conditioning treatments increase plant thermotolerance but do not induce thermotolerance in R. similis. Heat treatments have promise as disinfection protocols for quarantines.

  7. Heat exchanger leakage problem location

    Directory of Open Access Journals (Sweden)

    Jícha Miroslav

    2012-04-01

    Full Text Available Recent compact heat exchangers are very often assembled from numerous parts joined together to separate heat transfer fluids and to form the required heat exchanger arrangement. Therefore, the leak tightness is very important property of the compact heat exchangers. Although, the compact heat exchangers have been produced for many years, there are still technological problems associated with manufacturing of the ideal connection between the individual parts, mainly encountered with special purpose heat exchangers, e.g. gas turbine recuperators. This paper describes a procedure used to identify the leakage location inside the prime surface gas turbine recuperator. For this purpose, an analytical model of the leaky gas turbine recuperator was created to assess its performance. The results obtained are compared with the experimental data which were acquired during the recuperator thermal performance analysis. The differences between these two data sets are used to indicate possible leakage areas.

  8. Heat exchanger and related methods

    Science.gov (United States)

    Turner, Terry D.; McKellar, Michael G.

    2015-12-22

    Heat exchangers include a housing having an inlet and an outlet and forming a portion of a transition chamber. A heating member may form another portion of the transition chamber. The heating member includes a first end having a first opening and a second end having a second opening larger than the first opening. Methods of conveying a fluid include supplying a first fluid into a transition chamber of a heat exchanger, supplying a second fluid into the transition chamber, and altering a state of a portion of the first fluid with the second fluid. Methods of sublimating solid particles include conveying a first fluid comprising a material in a solid state into a transition chamber, heating the material to a gaseous state by directing a second fluid through a heating member and mixing the first fluid and the second fluid.

  9. Heat Transfer Basics and Practice

    CERN Document Server

    Böckh, Peter

    2012-01-01

    The book provides an easy way to understand the fundamentals of heat transfer. The reader will acquire the ability to design and analyze heat exchangers. Without extensive derivation of the fundamentals, the latest correlations for heat transfer coefficients and their application are discussed. The following topics are presented - Steady state and transient heat conduction - Free and forced convection - Finned surfaces - Condensation and boiling - Radiation - Heat exchanger design - Problem-solving After introducing the basic terminology, the reader is made familiar with the different mechanisms of heat transfer. Their practical application is demonstrated in examples, which are available in the Internet as MathCad files for further use. Tables of material properties and formulas for their use in programs are included in the appendix. This book will serve as a valuable resource for both students and engineers in the industry. The author’s experience indicates that students, after 40 lectures and exercises ...

  10. Large-scale solar heating

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, J.; Konttinen, P.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    Solar heating market is growing in many European countries and annually installed collector area has exceeded one million square meters. There are dozens of collector manufacturers and hundreds of firms making solar heating installations in Europe. One tendency in solar heating is towards larger systems. These can be roof integrated, consisting of some tens or hundreds of square meters of collectors, or they can be larger centralized solar district heating plants consisting of a few thousand square meters of collectors. The increase of size can reduce the specific investments of solar heating systems, because e.g. the costs of some components (controllers, pumps, and pipes), planning and installation can be smaller in larger systems. The solar heat output can also be higher in large systems, because more advanced technique is economically viable

  11. Magnetic heat pump flow director

    Science.gov (United States)

    Howard, Frank S. (Inventor)

    1995-01-01

    A fluid flow director is disclosed. The director comprises a handle body and combed-teeth extending from one side of the body. The body can be formed of a clear plastic such as acrylic. The director can be used with heat exchangers such as a magnetic heat pump and can minimize the undesired mixing of fluid flows. The types of heat exchangers can encompass both heat pumps and refrigerators. The director can adjust the fluid flow of liquid or gas along desired flow directions. A method of applying the flow director within a magnetic heat pump application is also disclosed where the comb-teeth portions of the director are inserted into the fluid flow paths of the heat pump.

  12. Large-scale solar heat

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, J.; Konttinen, P.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics

    1998-12-31

    In this project a large domestic solar heating system was built and a solar district heating system was modelled and simulated. Objectives were to improve the performance and reduce costs of a large-scale solar heating system. As a result of the project the benefit/cost ratio can be increased by 40 % through dimensioning and optimising the system at the designing stage. (orig.)

  13. A special relativistic heat engine

    Directory of Open Access Journals (Sweden)

    William S. Cariens

    1983-01-01

    main concepts taken from themodynamics and special relativity are those of a heat engine and E=mc2 respectively. Central to understanding the operation of this relativistic heat engine is the fact that upon heating a mass, its rest mass increases! This concept is nonexistent in classical thermodynamics. An increase in rest mass means that both the internal energy of a mass and its macroscopic kinetic energy increase!!!

  14. Mathematical model of heat pump

    OpenAIRE

    Pitron, J.

    2015-01-01

    In this paper different energy states of a heat pump are described. Equations used for mathematical description of the heat pump in the Matlab Simulink are presented. Created model is used to calculate the energy flows in the system according to different input parameters. The simulation involves an accumulation tank, which is controlled by individual input and output parameters. Simulation results have been compared with the experimental measured values on a heat pump in a laboratory.

  15. Racemization of Valine by Impact-Induced Heating

    Science.gov (United States)

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

    2017-05-01

    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 uc(d)- and uc(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.

  16. Cancer survival in Cuba, 1994-1995.

    Science.gov (United States)

    Garrote, L F; Alvarez, Y G; Babie, P T; Yi, M G; Alvarez, M G; Cicili, M L

    2011-01-01

    The population-based cancer registry in Cuba is a national cancer registry established in 1964; cancer registration is entirely done by passive methods. Data on survival from 13 cancer sites or types registered during 1994-1995 are reported. Follow-up has been carried out predominantly by passive methods, with median follow-up ranging from 13-54 months. The proportion with histologically verified diagnosis for various cancers ranged between 34-100%; death certificates only (DCOs) comprised 8-50%; 50-89% of total registered cases were included for the survival analysis. The 5-year age-standardized relative survival for selected cancers were breast (69%), colon (41%), cervix (56%), urinary bladder (64%), rectum (48%) and non-Hodgkin lymphoma (49%). The 5-year relative survival by age group showed no distinct pattern or trend, and was fluctuating. A decreasing survival with increasing clinical extent of disease was noted for all cancers studied. The data on survival trend revealed that the 5-year relative survival of most cancers diagnosed in 1994-1995 was greater than that in 1988-1989.

  17. Linking age, survival, and transit time distributions

    Science.gov (United States)

    Calabrese, Salvatore; Porporato, Amilcare

    2015-10-01

    Although the concepts of age, survival, and transit time have been widely used in many fields, including population dynamics, chemical engineering, and hydrology, a comprehensive mathematical framework is still missing. Here we discuss several relationships among these quantities by starting from the evolution equation for the joint distribution of age and survival, from which the equations for age and survival time readily follow. It also becomes apparent how the statistical dependence between age and survival is directly related to either the age dependence of the loss function or the survival-time dependence of the input function. The solution of the joint distribution equation also allows us to obtain the relationships between the age at exit (or death) and the survival time at input (or birth), as well as to stress the symmetries of the various distributions under time reversal. The transit time is then obtained as a sum of the age and survival time, and its properties are discussed along with the general relationships between their mean values. The special case of steady state case is analyzed in detail. Some examples, inspired by hydrologic applications, are presented to illustrate the theory with the specific results. This article was corrected on 11 Nov 2015. See the end of the full text for details.

  18. Heat shock suppresses mating and sperm transfer in the rice leaf folder Cnaphalocrocis medinalis.

    Science.gov (United States)

    Liao, H J; Qian, Q; Liu, X D

    2014-06-01

    Temperature is a key environmental factor in determining the population size of Cnaphalocrocis medinalis in summer. High temperatures inhibit survival, development and fecundity of this insect. However, biological responses of female and male adults to heat shock, and physiological mechanism of high temperature suppressing population development are still ambiguous. We experimentally tested the impact of heat shock (5 h day-1) on biological traits, spermatogenesis and sperm transfer of adults of C. medinalis. The result showed that heat exposure to 39 and 40 °C for 5 h reduced longevity and copulation frequency of adults, and hatchability of eggs. Immediate survival rate of males was lower than that of females after 3 days of exposure to 41 °C. The oviposition period, copulation frequency, fecundity of adults and hatchability of eggs were significantly lower when male adults were exposed to 40 or 41 °C for 3 days. Heat shock decreased frequency and success rate of mating when males were exposed, and it also resulted in postponement of mating behaviour and prolongation of mating duration as both the female and male adults were exposed. Heat shock did not affect spermatogenesis, but significantly inhibited sperms maturation. Moreover, males could not ejaculate sperm into females during copulation when these male moths received heat shock. Heat shock remarkably suppressed mating behaviour and sperm transfer, which led to a dramatic decline of rice leaf folder populations.

  19. Quantum optomechanical heat engine.

    Science.gov (United States)

    Zhang, Keye; Bariani, Francesco; Meystre, Pierre

    2014-04-18

    We investigate theoretically a quantum optomechanical realization of a heat engine. In a generic optomechanical arrangement the optomechanical coupling between the cavity field and the oscillating end mirror results in polariton normal mode excitations whose character depends on the pump detuning and the coupling strength. By varying that detuning it is possible to transform their character from phononlike to photonlike, so that they are predominantly coupled to the thermal reservoir of phonons or photons, respectively. We exploit the fact that the effective temperatures of these two reservoirs are different to produce an Otto cycle along one of the polariton branches. We discuss the basic properties of the system in two different regimes: in the optical domain it is possible to extract work from the thermal energy of a mechanical resonator at finite temperature, while in the microwave range one can in principle exploit the cycle to extract work from the blackbody radiation background coupled to an ultracold atomic ensemble.

  20. Heat transfer physics

    CERN Document Server

    Kaviany, Massoud

    2014-01-01

    This graduate textbook describes atomic-level kinetics (mechanisms and rates) of thermal energy storage, transport (conduction, convection, and radiation), and transformation (various energy conversions) by principal energy carriers. The approach combines the fundamentals of molecular orbitals-potentials, statistical thermodynamics, computational molecular dynamics, quantum energy states, transport theories, solid-state and fluid-state physics, and quantum optics. The textbook presents a unified theory, over fine-structure/molecular-dynamics/Boltzmann/macroscopic length and time scales, of heat transfer kinetics in terms of transition rates and relaxation times, and its modern applications, including nano- and microscale size effects. Numerous examples, illustrations, and homework problems with answers that enhance learning are included. This new edition includes applications in energy conversion (including chemical bond, nuclear, and solar), expanded examples of size effects, inclusion of junction quantum tr...

  1. Ceramic heat exchanger

    Science.gov (United States)

    LaHaye, P.G.; Rahman, F.H.; Lebeau, T.P.; Severin, B.K.

    1998-06-16

    A tube containment system is disclosed. The tube containment system does not significantly reduce heat transfer through the tube wall. The contained tube is internally pressurized, and is formed from a ceramic material having high strength, high thermal conductivity, and good thermal shock resistance. The tube containment system includes at least one ceramic fiber braid material disposed about the internally pressurized tube. The material is disposed about the tube in a predetermined axial spacing arrangement. The ceramic fiber braid is present in an amount sufficient to contain the tube if the tube becomes fractured. The tube containment system can also include a plurality of ceramic ring-shaped structures, in contact with the outer surface of the tube, and positioned between the tube and the ceramic fiber braid material, and/or at least one transducer positioned within tube for reducing the internal volume and, therefore, the energy of any shrapnel resulting from a tube fracture. 6 figs.

  2. Heat flux solarimeter

    Energy Technology Data Exchange (ETDEWEB)

    Sartarelli, A.; Vera, S.; Cyrulies, E. [Instituto de Desarrollo Humano, Univ. Nac. de Gral. Sarmiento (IDH, UNGS), Los Polvorines (Argentina); Echarri, R. [Instituto de Desarrollo Humano, Univ. Nac. de Gral. Sarmiento (IDH, UNGS), Los Polvorines (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Samson, I. [INTEC (Instituto Tecnologico Santo Domingo), Santo Domingo (Dominican Republic)

    2010-12-15

    The solarimeter presented in this work is easy to assemble. It is calibrated and its performance is validated by means of Hottel's method. Finally, the curves obtained with this solarimeter are compared to the ones obtained with a commercial solarimeter. This device is based on the evaluation of the heat flow in a metal rod. In consequence, measurements are not affected by ambient temperature variations. On the other hand, there is a linear relationship between the temperatures measured at the rod ends and the incident radiation, as can be concluded both from the theory of its operation and the calibration lines obtained. The results obtained from the global irradiance measurements in the area of Los Polvorines (Buenos Aires Province), together with a preliminary evaluation of the solarimeter's response time, are presented in this work. (author)

  3. Combined Heat and Power

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    At their 2007 Summit in Heiligendamm, G8 leaders called on countries to 'adopt instruments and measures to significantly increase the share of combined heat and power (CHP) in the generation of electricity.' As a result, energy, economic, environmental and utility regulators are looking for tools and information to understand the potential of CHP and to identify appropriate policies for their national circumstances. This report forms the first part of the response. It includes answers to policy makers' questions about the potential economic, energy and environmental benefits of an increased policy commitment to CHP. It also includes for the first time integrated IEA data on global CHP installations, and analyses the benefits of increased CHP investment in the G8+5 countries. A companion report will be produced later in 2008 to document best practice policy approaches that have been used to expand the use of CHP in a variety of countries.

  4. Waste heat recovery system

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Timothy C.; Zigan, James A.

    2017-12-19

    A waste heat recovery system includes a Rankine cycle (RC) circuit having a pump, a boiler, an energy converter, and a condenser fluidly coupled via conduits in that order, to provide additional work. The additional work is fed to an input of a gearbox assembly including a capacity for oil by mechanically coupling to the energy converter to a gear assembly. An interface is positioned between the RC circuit and the gearbox assembly to partially restrict movement of oil present in the gear assembly into the RC circuit and partially restrict movement of working fluid present in the RC circuit into the gear assembly. An oil return line is fluidly connected to at least one of the conduits fluidly coupling the RC components to one another and is operable to return to the gear assembly oil that has moved across the interface from the gear assembly to the RC circuit.

  5. Thermal radiation heat transfer.

    Science.gov (United States)

    Siegel, R.; Howell, J. R.

    1972-01-01

    A comprehensive discussion of heat transfer by thermal radiation is presented, including the radiative behavior of materials, radiation between surfaces, and gas radiation. Among the topics considered are property prediction by electromagnetic theory, the observed properties of solid materials, radiation in the presence of other modes of energy transfer, the equations of transfer for an absorbing-emitting gas, and radiative transfer in scattering and absorbing media. Also considered are radiation exchange between black isothermal surfaces, radiation exchange in enclosures composed of diffuse gray surfaces and in enclosures having some specularly reflecting surfaces, and radiation exchange between nondiffuse nongray surfaces. The use of the Monte Carlo technique in solving radiant-exchange problems and problems of radiative transfer through absorbing-emitting media is explained.

  6. Survival analysis of orthodontic mini-implants.

    Science.gov (United States)

    Lee, Shin-Jae; Ahn, Sug-Joon; Lee, Jae Won; Kim, Seong-Hun; Kim, Tae-Woo

    2010-02-01

    Survival analysis is useful in clinical research because it focuses on comparing the survival distributions and the identification of risk factors. Our aim in this study was to investigate the survival characteristics and risk factors of orthodontic mini-implants with survival analyses. One hundred forty-one orthodontic patients (treated from October 1, 2000, to November 29, 2007) were included in this survival study. A total of 260 orthodontic mini-implants that had sandblasted (large grit) and acid-etched screw parts were placed between the maxillary second premolar and the first molar. Failures of the implants were recorded as event data, whereas implants that were removed because treatment ended and those that were not removed during the study period were recorded as censored data. A nonparametric life table method was used to visualize the hazard function, and Kaplan-Meier survival curves were generated to identify the variables associated with implant failure. Prognostic variables associated with implant failure were identified with the Cox proportional hazard model. Of the 260 implants, 22 failed. The hazard function for implant failure showed that the risk is highest immediately after placement. The survival function showed that the median survival time of orthodontic mini-implants is sufficient for relatively long orthodontic treatments. The Cox proportional hazard model identified that increasing age is a decisive factor for implant survival. The decreasing pattern of the hazard function suggested gradual osseointegration of orthodontic mini-implants. When implants are placed in a young patient, special caution is needed to lessen the increased probability of failure, especially immediately after placement.

  7. Heat Flux Instrumentation Laboratory (HFIL)

    Data.gov (United States)

    Federal Laboratory Consortium — Description: The Heat Flux Instrumentation Laboratory is used to develop advanced, flexible, thin film gauge instrumentation for the Air Force Research Laboratory....

  8. The theory of heat radiation

    CERN Document Server

    Planck, Max

    2003-01-01

    Nobel laureate's classic exposition of the theory of radiant heat in terms of quantum action. Kirchoff's law, black radiation, Maxwell's radiation pressure, entropy, other topics. 1914 edition. Bibliography.

  9. Urban Heat Wave Hazard Assessment

    Science.gov (United States)

    Quattrochi, D. A.; Jedlovec, G.; Crane, D. L.; Meyer, P. J.; LaFontaine, F.

    2016-12-01

    Heat waves are one of the largest causes of environmentally-related deaths globally and are likely to become more numerous as a result of climate change. The intensification of heat waves by the urban heat island effect and elevated humidity, combined with urban demographics, are key elements leading to these disasters. Better warning of the potential hazards may help lower risks associated with heat waves. Moderate resolution thermal data from NASA satellites is used to derive high spatial resolution estimates of apparent temperature (heat index) over urban regions. These data, combined with demographic data, are used to produce a daily heat hazard/risk map for selected cities. MODIS data are used to derive daily composite maximum and minimum land surface temperature (LST) fields to represent the amplitude of the diurnal temperature cycle and identify extreme heat days. Compositing routines are used to generate representative daily maximum and minimum LSTs for the urban environment. The limited effect of relative humidity on the apparent temperature (typically 10-15%) allows for the use of modeled moisture fields to convert LST to apparent temperature without loss of spatial variability. The daily max/min apparent temperature fields are used to identify abnormally extreme heat days relative to climatological values in order to produce a heat wave hazard map. Reference to climatological values normalizes the hazard for a particular region (e.g., the impact of an extreme heat day). A heat wave hazard map has been produced for several case study periods and then computed on a quasi-operational basis during the summer of 2016 for Atlanta, GA, Chicago, IL, St. Louis, MO, and Huntsville, AL. A hazard does not become a risk until someone or something is exposed to that hazard at a level that might do harm. Demographic information is used to assess the urban risk associated with the heat wave hazard. Collectively, the heat wave hazard product can warn people in urban

  10. Ohmic heating in food processing

    National Research Council Canada - National Science Library

    Ramaswamy, Hosahalli S; Marcotte, Michèle; Sastry, Sudhir K; Abdelrahim, Khalid Ali

    2014-01-01

    "This special volume is devoted to Ohmic heating of foods covering several aspects of its science and engineering, chemistry and physics, biochemistry and nutrition, quality and safety, development...

  11. Users of electric heating rewarded

    Energy Technology Data Exchange (ETDEWEB)

    Haapakoski, M. [ed.

    1998-07-01

    When the building industry plunged into the deep recession of the early 1990s this did not paralyse research and development work on electric heating. In fact, IVO and power companies launched the `Electrically Heated Homes in the New Millennium` project in 1992. Its purpose was to verify the efficiency, energy economy and residential comfort of model systems using state-of-the-art electric heating technology. The research project launched six years ago is now nearing completion. Its findings indicate that electricity brings ever more unparalleled benefits when it is used for heating. These benefits involve residential comfort, ease of use and economy

  12. Umbilical Cord Blood-Derived Stem Cells Improve Heat Tolerance and Hypothalamic Damage in Heat Stressed Mice

    Directory of Open Access Journals (Sweden)

    Ling-Shu Tseng

    2014-01-01

    Full Text Available Heatstroke is characterized by excessive hyperthermia associated with systemic inflammatory responses, which leads to multiple organ failure, in which brain disorders predominate. This definition can be almost fulfilled by a mouse model of heatstroke used in the present study. Unanesthetized mice were exposed to whole body heating (41.2°C for 1 hour and then returned to room temperature (26°C for recovery. Immediately after termination of whole body heating, heated mice displayed excessive hyperthermia (body core temperature ~42.5°C. Four hours after termination of heat stress, heated mice displayed (i systemic inflammation; (ii ischemic, hypoxic, and oxidative damage to the hypothalamus; (iii hypothalamo-pituitary-adrenocortical axis impairment (reflected by plasma levels of both adrenocorticotrophic-hormone and corticosterone; (iv decreased fractional survival; and (v thermoregulatory deficits (e.g., they became hypothermia when they were exposed to room temperature. These heatstroke reactions can be significantly attenuated by human umbilical cord blood-derived CD34+ cells therapy. Our data suggest that human umbilical cord blood-derived stem cells therapy may improve outcomes of heatstroke in mice by reducing systemic inflammation as well as hypothalamo-pituitary-adrenocortical axis impairment.

  13. Gas turbine heat transfer and cooling technology

    CERN Document Server

    Han, Je-Chin; Ekkad, Srinath

    2012-01-01

    FundamentalsNeed for Turbine Blade CoolingTurbine-Cooling TechnologyTurbine Heat Transfer and Cooling IssuesStructure of the BookReview Articles and Book Chapters on Turbine Cooling and Heat TransferNew Information from 2000 to 2010ReferencesTurbine Heat TransferIntroductionTurbine-Stage Heat TransferCascade Vane Heat-Transfer ExperimentsCascade Blade Heat TransferAirfoil Endwall Heat TransferTurbine Rotor Blade Tip Heat TransferLeading-Edge Region Heat TransferFlat-Surface Heat TransferNew Information from 2000 to 20102.10 ClosureReferencesTurbine Film CoolingIntroductionFilm Cooling on Rotat

  14. Measurement and Evaluation of Heating Performance of Heat Pump Systems Using Wasted Heat from Electric Devices for an Electric Bus

    OpenAIRE

    Cho, Chung-Won; Lee, Ho-Seong; Won, Jong-Phil; Lee, Moo-Yeon

    2012-01-01

    The objective of this study is to investigate heating performance characteristics of a coolant source heat pump using the wasted heat from electric devices for an electric bus. The heat pump, using R-134a, is designed for heating a passengers’ compartment by using discharged energy from the coolant of electric devices, such as motors and inverters of the electric bus. The heating performance of the heat pump was tested by varying the operating parameters, such as outdoor temperature and volum...

  15. Induction Heating Model of Cermet Fuel Element Environmental Test (CFEET)

    Science.gov (United States)

    Gomez, Carlos F.; Bradley, D. E.; Cavender, D. P.; Mireles, O. R.; Hickman, R. R.; Trent, D.; Stewart, E.

    2013-01-01

    Deep space missions with large payloads require high specific impulse and relatively high thrust to achieve mission goals in reasonable time frames. Nuclear Thermal Rockets (NTR) are capable of producing a high specific impulse by employing heat produced by a fission reactor to heat and therefore accelerate hydrogen through a rocket nozzle providing thrust. Fuel element temperatures are very high (up to 3000 K) and hydrogen is highly reactive with most materials at high temperatures. Data covering the effects of high-temperature hydrogen exposure on fuel elements are limited. The primary concern is the mechanical failure of fuel elements due to large thermal gradients; therefore, high-melting-point ceramics-metallic matrix composites (cermets) are one of the fuels under consideration as part of the Nuclear Cryogenic Propulsion Stage (NCPS) Advance Exploration System (AES) technology project at the Marshall Space Flight Center. The purpose of testing and analytical modeling is to determine their ability to survive and maintain thermal performance in a prototypical NTR reactor environment of exposure to hydrogen at very high temperatures and obtain data to assess the properties of the non-nuclear support materials. The fission process and the resulting heating performance are well known and do not require that active fissile material to be integrated in this testing. A small-scale test bed; Compact Fuel Element Environmental Tester (CFEET), designed to heat fuel element samples via induction heating and expose samples to hydrogen is being developed at MSFC to assist in optimal material and manufacturing process selection without utilizing fissile material. This paper details the analytical approach to help design and optimize the test bed using COMSOL Multiphysics for predicting thermal gradients induced by electromagnetic heating (Induction heating) and Thermal Desktop for radiation calculations.

  16. Foreign Ownership and long-term Survival

    OpenAIRE

    Kronborg, Dorte; Thomsen, Steen

    2006-01-01

    Does foreign ownership enhance or decrease a firm’s chances of survival? Over the 100 year period 1895-2001 this paper compares the survival of foreign subsidiaries in Denmark to a control sample matched by industry and firm size. We find that foreign-owned companies have higher survival probability. On average exit risk for domestic companies is 2.3 times higher than for foreign companies. First movers like Siemens, Philips, Kodak, Ford, GM or Goodyear have been active in the country for alm...

  17. Controlling chaotic transients: Yorke's game of survival

    DEFF Research Database (Denmark)

    Aguirre, Jacobo; D'ovidio, Francesco; Sanjuán, Miguel A. F.

    2004-01-01

    . This problem is focused as a two-person, mathematical game between two players called "the protagonist" and "the adversary." The protagonist's goal is to survive. He can lose but cannot win; the best he can do is survive to play another round, struggling ad infinitum. In the absence of actions by either player...... knows the action of the adversary in choosing his response and is permitted to choose the initial point x(0) of the game. We use the "slope 3" tent map in an example of this problem. We show that it is possible for the protagonist to survive....

  18. Empirical likelihood method in survival analysis

    CERN Document Server

    Zhou, Mai

    2015-01-01

    Add the Empirical Likelihood to Your Nonparametric ToolboxEmpirical Likelihood Method in Survival Analysis explains how to use the empirical likelihood method for right censored survival data. The author uses R for calculating empirical likelihood and includes many worked out examples with the associated R code. The datasets and code are available for download on his website and CRAN.The book focuses on all the standard survival analysis topics treated with empirical likelihood, including hazard functions, cumulative distribution functions, analysis of the Cox model, and computation of empiric

  19. Streptococcus mutans copes with heat stress by multiple transcriptional regulons modulating virulence and energy metabolism

    Science.gov (United States)

    Liu, Chengcheng; Niu, Yulong; Zhou, Xuedong; Zheng, Xin; Wang, Shida; Guo, Qiang; Li, Yuqing; Li, Mingyun; Li, Jiyao; Yang, Yi; Ding, Yi; Lamont, Richard J.; Xu, Xin

    2015-01-01

    Dental caries is closely associated with the virulence of Streptococcus mutans. The virulence expression of S. mutans is linked to its stress adaptation to the changes in the oral environment. In this work we used whole-genome microarrays to profile the dynamic transcriptomic responses of S. mutans during physiological heat stress. In addition, we evaluated the phenotypic changes, including, eDNA release, initial biofilm formation, extracellular polysaccharides generation, acid production/acid tolerance, and ATP turnover of S. mutans during heat stress. There were distinct patterns observed in the way that S. mutans responded to heat stress that included 66 transcription factors for the expression of functional genes being differentially expressed. Especially, response regulators of two component systems (TCSs), the repressors of heat shock proteins and regulators involved in sugar transporting and metabolism co-ordinated to enhance the cell’s survival and energy generation against heat stress in S. mutans. PMID:26251057

  20. One-dimensional heat conduction equation of the polar bear hair

    Directory of Open Access Journals (Sweden)

    Zhu Wei-Hong

    2015-01-01

    Full Text Available Hairs of a polar bear (Ursus maritimus possess special membrane-pore structure. The structure enables the polar bear to survive in the harsh Arctic regions. In this paper, the membrane-pore structure be approximately considered as fractal space, 1-D heat conduction equation of the polar bear hair is established and the solution of the equation is obtained.