WorldWideScience

Sample records for ambient temperature

  1. Ambient temperature recorder

    Science.gov (United States)

    Russell, Larry D.

    1991-01-01

    A temperature data recorder, designated the Ambient Temperature Recorder (ATR-4), was developed at NASA Ames Research Center to meet particular requirements for space life sciences experiments. The small, self-contained, four-channel, battery-powered device records 32 kilobytes of temperature data over a range of -40 to +60 C at four sampling intervals ranging from 1.875 to 15 minutes. Data is stored in its internal electronic memory for later readout by a personal computer.

  2. Ambient temperature signalling in plants.

    Science.gov (United States)

    Wigge, Philip A

    2013-10-01

    Plants are exposed to daily and seasonal fluctuations in temperature. Within the 'ambient' temperature range (about 12-27°C for Arabidopsis) temperature differences have large effects on plant growth and development, disease resistance pathways and the circadian clock without activating temperature stress pathways. It is this developmental sensing and response to non-stressful temperatures that will be covered in this review. Recent advances have revealed key players in mediating temperature signals. The bHLH transcription factor PHYTOCHROME INTERACTING FACTOR4 (PIF4) has been shown to be a hub for multiple responses to warmer temperature in Arabidopsis, including flowering and hypocotyl elongation. Changes in chromatin state are involved in transmitting temperature signals to the transcriptome. Determining the precise mechanisms of temperature perception represents an exciting goal for the field.

  3. The relationship between body and ambient temperature and corneal temperature

    DEFF Research Database (Denmark)

    Kessel, Line; Johnson, Leif; Arvidsson, Henrik Sven

    2010-01-01

    Exposure to elevated ambient temperatures has been mentioned as a risk factor for common eye diseases, primarily presbyopia and cataract. The aim of the present study was to examine the relationship among ambient, cornea, and body core temperature.......Exposure to elevated ambient temperatures has been mentioned as a risk factor for common eye diseases, primarily presbyopia and cataract. The aim of the present study was to examine the relationship among ambient, cornea, and body core temperature....

  4. Electronic Ambient-Temperature Recorder

    Science.gov (United States)

    Russell, Larry; Barrows, William

    1995-01-01

    Electronic temperature-recording unit stores data in internal memory for later readout. Records temperatures from minus 40 degrees to plus 60 degrees C at intervals ranging from 1.875 to 15 minutes. With all four data channels operating at 1.875-minute intervals, recorder stores at least 10 days' data. For only one channel at 15-minute intervals, capacity extends to up to 342 days' data. Developed for recording temperatures of instruments and life-science experiments on satellites, space shuttle, and high-altitude aircraft. Adaptable to such terrestrial uses as recording temperatures of perishable goods during transportation and of other systems or processes over long times. Can be placed directly in environment to monitor.

  5. Water Loss Under Hot Ambient Temperatures

    Directory of Open Access Journals (Sweden)

    S. K. Basu

    1978-07-01

    Full Text Available Male 4 rates were ambient temperature (40 degree,42 degree, and 44 degree calcius for different durations of time upto a maximum of 3 hours. It was observed that there was a rapid loss in body weight accompanied by considerable increase in body temperature of the animals during the first hour of exposure. Thereafter the rate of body weight loss and increase in body temperature were slow till the end of observation period. Intolerance to heat appears to be more correlated with critical body temperature rather than the extent of dehydration.

  6. Water Power Calculator Temperature and Analog Input/Output Module Ambient Temperature Testing

    Energy Technology Data Exchange (ETDEWEB)

    Mark D. McKay

    2011-02-01

    Water Power Calculator Temperature and Analog input/output Module Ambient Temperature Testing A series of three ambient temperature tests were conducted for the Water Power Calculator development using the INL Calibration Laboratory’s Tenney Environmental Chamber. The ambient temperature test results demonstrate that the Moore Industries Temperature Input Modules, Analog Input Module and Analog Output Module, ambient temperature response meet or exceed the manufactures specifications

  7. Effect of ambient temperature on female endurance performance.

    Science.gov (United States)

    Renberg, Julie; Sandsund, Mariann; Wiggen, Øystein Nordrum; Reinertsen, Randi Eidsmo

    2014-10-01

    Ambient temperature can affect physical performance, and an ambient temperature range of -4 °C to 11 °C is optimal for endurance performance in male athletes. The few similar studies of female athletes appear to have found differences in response to cold between the genders. This study investigated whether ambient temperature affects female endurance performance. Nine athletes performed six tests while running on a treadmill in a climatic chamber at different ambient temperatures: 20, 10, 1, -4, -9 and -14 °C and a wind speed of 5 m s(-1). The exercise protocol consisted of a 10-min warm-up, followed by four 5-min intervals at increasing intensities at 76%, 81%, 85%, and 89% of maximal oxygen consumption. This was followed by an incremental test to exhaustion. Although peak heart rate, body mass loss, and blood lactate concentration after the incremental test to exhaustion increased as the ambient temperature rose, no changes in time to exhaustion, running economy, running speed at lactate threshold or maximal oxygen consumption were found between the different ambient temperature conditions. Endurance performance during one hour of incremental exercise was not affected by ambient temperature in female endurance athletes.

  8. Entrainment of circadian rhythm by ambient temperature cycles in mice.

    Science.gov (United States)

    Refinetti, Roberto

    2010-08-01

    Much is known about how environmental light-dark cycles synchronize circadian rhythms in animals. The ability of environmental cycles of ambient temperature to synchronize circadian rhythms has also been investigated extensively but mostly in ectotherms. In the present study, the synchronization of the circadian rhythm of running-wheel activity by environmental cycles of ambient temperature was studied in laboratory mice. Although all mice were successfully entrained by a light-dark cycle, only 60% to 80% of the mice were entrained by temperature cycles (24-32 degrees C or 24-12 degrees C), and attainment of stable entrainment seemed to take longer under temperature cycles than under a light-dark cycle. This suggests that ambient temperature cycles are weaker zeitgebers than light-dark cycles, which is consistent with the results of the few previous studies using mammalian species. Whereas 80% of the mice were entrained by 24-h temperature cycles, only 60% were entrained by 23-h cycles, and none was entrained by 25-h cycles. The results did not clarify whether entrainment by temperature cycles is caused directly by temperature or indirectly through a temperature effect on locomotor activity, but it is clear that the rhythm of running-wheel activity in mice can be entrained by ambient temperature cycles in the nonnoxious range.

  9. Low ambient temperature and neuroendocrine response to hypoglycemia in men.

    Science.gov (United States)

    Jezová, D; Juránková, E; Kvetnanský, R; Kaciuba-Uscilko, H; Nazar, K; Vigas, M

    1995-12-01

    Nutritional factors, such as an excess or a deficiency of glucose, play an important role in neuroendocrine regulations. Hormonal and metabolic responses to hypoglycemia were examined in healthy non-obese volunteers under conditions of low ambient temperature. Hypoglycemia was induced by intravenous injection of insulin in two randomized trials performed at room temperature and at 4 degrees C. At room temperature, the typical neuroendocrine response to hypoglycemia was established. The increases of ACTH, beta-endorphin, growth hormone and cortisol in response to insulin hypoglycemia failed to be modified by low ambient temperature. Acute cold exposure significantly reduced epinephrine and totally inhibited prolactin response to insulin-induced hypoglycemia. In spite of significant changes in epinephrine response to hypoglycemia at low ambient temperature, no striking differences in plasma glucose levels compared to those measured at room temperature were observed. However, under conditions of low temperature the reestablishment of normoglycemia was delayed. No changes in free fatty acids were found under our experimental conditions. The presented data show that low ambient temperature exerts selective effects on some neuroendocrine and metabolic parameters.

  10. Ambient temperature perception in papaya for papaya ringspot virus interaction.

    Science.gov (United States)

    Mangrauthia, Satendra K; Singh Shakya, Viplendra P; Jain, R K; Praveen, Shelly

    2009-06-01

    Temperature dramatically affects the host-virus interaction. Outbreaks of viral diseases are frequently associated with the ambient temperature required for host development. Using papaya as a host and Papaya ringspot virus (PRSV) as a pathogen, we studied the effect of temperature on the intensity of disease symptoms and virus accumulation. The phenotypic expression of symptoms and viral accumulation were found to be maximum at ambient temperature (26-31 degrees C) of papaya cultivation. However, there was a drastic difference, 10 degrees C above and below the ambient temperature. The underlying mechanism of these well-known observations are not yet understood completely; however, these observations might help find answers in RNA silencing mechanism of plants. Since viral-derived silencing suppressor proteins play a significant role in RNA silencing mechanism, here we show that PRSV-derived Helper component proteinase (HC-Pro) protein has an affinity for small RNAs in a temperature-dependent manner. This suggested the probable role of HC-Pro in the temperature-regulated host-virus relationship.

  11. Effect of Gas Turbine Exhaust Temperature, Stack Temperature and Ambient Temperature on Overall Efficiency of Combine Cycle Power Plant

    OpenAIRE

    Khan, M N; K.P.Tyagi

    2010-01-01

    The gas turbine exhaust temperature, stack temperature and ambient temperature play a very important role during the predication of the performance of combine cycle power plant. This paper covers parametric analysis of effects of gas turbine exhaust temperature, stack temperature and ambient temperature on the overall efficiency of combine cycle power plant keeping the gas turbine efficiency as well as steam turbine efficiency constant. The results shows that out of three variables i.e. turbi...

  12. Ambient air temperature effects on the temperature of sewage sludge composting process

    Institute of Scientific and Technical Information of China (English)

    HUANG Qi-fei; CHEN Tong-bin; GAO Ding; HUANG Ze-chun

    2005-01-01

    Using data obtained with a full-scale sewage sludge composting facility, this paper studied the effects of ambient air temperature on the composting temperature with varying volume ratios of sewage sludge and recycled compost to bulking agent. Two volume ratios were examined experimentally, 1: 0: 1 and 3: 1: 2. The results show that composting temperature was influenced by ambient air temperature and the influence was more significant when composting was in the temperature rising process: composting temperature changed 2.4-6.5℃ when ambient air temperature changed 13℃. On the other hand, the influence was not significant when composting was in the high-temperature and/or temperature falling process: composting temperature changed 0.75-1.3℃ when ambient air temperature changed 8-15 ℃. Hysteresis effect was observed in composting temperature's responses to ambient air temperature. When the ventilation capability of pile was excellent(at a volume ratio of 1:0:1), the hysteresis time was short and ranging 1.1-1.2 h. On the contrary, when the proportion of added bulking agent was low, therefore less porosity in the substrate(at a volume ratio of 3:1:2), the hysteresis time was long and ranging 1.9-3.1 h.

  13. Apparatus for storage of compressed gas at ambient temperature

    Energy Technology Data Exchange (ETDEWEB)

    Lowther, F.E.

    1986-10-28

    This patent describes an engine system including a combustion engine and an oxidizer subsystem for high density gaseous oxidizer. The oxidizer subsystem comprises: a storage vessel; adsorbent material in the storage vessel capable of adsorbing relatively large volumes of the gaseous oxidizer at ambient temperature and of preventing the instantaneous release thereof in the event of a rupture of the vessel, the storage vessel being operatively connected for delivery of oxidizer to the engine for combination with fuel therein to power the engine.

  14. [Research on Raman spectra of isooctane at ambient temperature and ambient pressure to 1. 2 GPa].

    Science.gov (United States)

    Zhang, Fei-fei; Zheng, Hai-fei

    2012-03-01

    The experimental study of the Raman spectral character for liquid isooctane (2,2,4-trimethylpentane, ATM) was con ducted by moissanite anvil cell at the pressure of 0-1.2 GPa and the ambient temperature. The results show that the Raman peaks of the C-H stretching vibration shift to higher frenquencies with increasing pressures. The relations between the system pressure and peaks positions is given as following: v2 873 = 0.002 8P+2 873.3; v2 905 = 0.004 8P+2 905.4; v2 935 = 0.002 7P+ 2 935.0; v2 960 = 0.012P+2 960.9. The Raman spectra of isooctane abruptly changed at the pressure about 1.0 GPa and the liquid-solid phase transition was observed by microscope. With the freezing pressure at ambient temperature and the melting temperature available at 1 atm, the authors got the liquid-solid phase diagram of isooctane. According to Clapeyron equation, the authors obtained the differences of volume and entropy for the liquid-solid phase transition of isooctane: deltaV(m) = 4.46 x 10(-6) m3 x mol-1 and deltaS = -30.32 J x K(-1) x mol(-1).

  15. Numerical Analysis of Exergy for Air-Conditioning Influenced by Ambient Temperature

    Directory of Open Access Journals (Sweden)

    Jing-Nang Lee

    2014-07-01

    Full Text Available The article presents numerical analysis of exergy for air-conditioning influenced by ambient temperature. The model of numerical simulation uses an integrated air conditioning system exposed in varied ambient temperature to observe change of the four main devices, the compressor, the condenser, the capillary, and the evaporator in correspondence to ambient temperature. The analysis devices of the four devices’s exergy influenced by the varied ambient temperature and found that the capillary has unusual increasing exergy loss vs. increasing ambient temperature in comparison to the other devices. The result shows that reducing exergy loss of the capillary influenced by the ambient temperature is the key for improving working efficiency of an air-conditioning system when influence of the ambient temperature is considered. The higher ambient temperature causes the larger pressure drop of capillary and more exergy loss.

  16. Photoelectron Spectroscopy under Ambient Pressure and Temperature Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ogletree, D. Frank; Bluhm, Hendrik; Hebenstreit, Eleonore B.; Salmeron, Miquel

    2009-02-27

    We describe the development and applications of novel instrumentation for photoemission spectroscopy of solid or liquid surfaces in the presence of gases under ambient conditions or pressure and temperature. The new instrument overcomes the strong scattering of electrons in gases by the use of an aperture close to the surface followed by a differentially-pumped electrostatic lens system. In addition to the scattering problem, experiments in the presence of condensed water or other liquids require the development of special sample holders to provide localized cooling. We discuss the first two generations of Ambient Pressure PhotoEmission Spectroscopy (APPES) instruments developed at synchrotron light sources (ALS in Berkeley and BESSY in Berlin), with special focus on the Berkeley instruments. Applications to environmental science and catalytic chemical research are illustrated in two examples.

  17. 14 CFR 25.1527 - Ambient air temperature and operating altitude.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ambient air temperature and operating... Information Operating Limitations § 25.1527 Ambient air temperature and operating altitude. The extremes of the ambient air temperature and operating altitude for which operation is allowed, as limited...

  18. Ambient temperature influences the neural benefits of exercise.

    Science.gov (United States)

    Maynard, Mark E; Chung, Chasity; Comer, Ashley; Nelson, Katharine; Tran, Jamie; Werries, Nadja; Barton, Emily A; Spinetta, Michael; Leasure, J Leigh

    2016-02-15

    Many of the neural benefits of exercise require weeks to manifest. It would be useful to accelerate onset of exercise-driven plastic changes, such as increased hippocampal neurogenesis. Exercise represents a significant challenge to the brain because it produces heat, but brain temperature does not rise during exercise in the cold. This study tested the hypothesis that exercise in cold ambient temperature would stimulate hippocampal neurogenesis more than exercise in room or hot conditions. Adult female rats had exercise access 2h per day for 5 days at either room (20 °C), cold (4.5 °C) or hot (37.5 °C) temperature. To label dividing hippocampal precursor cells, animals received daily injections of BrdU. Brains were immunohistochemically processed for dividing cells (Ki67+), surviving cells (BrdU+) and new neurons (doublecortin, DCX) in the hippocampal dentate gyrus. Animals exercising at room temperature ran significantly farther than animals exercising in cold or hot conditions (room 1490 ± 400 m; cold 440 ± 102 m; hot 291 ± 56 m). We therefore analyzed the number of Ki67+, BrdU+ and DCX+ cells normalized for shortest distance run. Contrary to our hypothesis, exercise in either cold or hot conditions generated significantly more Ki67+, BrdU+ and DCX+ cells compared to exercise at room temperature. Thus, a limited amount of running in either cold or hot ambient conditions generates more new cells than a much greater distance run at room temperature. Taken together, our results suggest a simple means by which to augment exercise effects, yet minimize exercise time.

  19. Effect of ambient temperature and relative humidity on interfacial temperature during early stages of drop evaporation.

    Science.gov (United States)

    Fukatani, Yuki; Orejon, Daniel; Kita, Yutaku; Takata, Yasuyuki; Kim, Jungho; Sefiane, Khellil

    2016-04-01

    Understanding drop evaporation mechanisms is important for many industrial, biological, and other applications. Drops of organic solvents undergoing evaporation have been found to display distinct thermal patterns, which in turn depend on the physical properties of the liquid, the substrate, and ambient conditions. These patterns have been reported previously to be bulk patterns from the solid-liquid to the liquid-gas drop interface. In the present work the effect of ambient temperature and humidity during the first stage of evaporation, i.e., pinned contact line, is studied paying special attention to the thermal information retrieved at the liquid-gas interface through IR thermography. This is coupled with drop profile monitoring to experimentally investigate the effect of ambient temperature and relative humidity on the drop interfacial thermal patterns and the evaporation rate. Results indicate that self-generated thermal patterns are enhanced by an increase in ambient temperature and/or a decrease in humidity. The more active thermal patterns observed at high ambient temperatures are explained in light of a greater temperature difference generated between the apex and the edge of the drop due to greater evaporative cooling. On the other hand, the presence of water humidity in the atmosphere is found to decrease the temperature difference along the drop interface due to the heat of adsorption, absorption and/or that of condensation of water onto the ethanol drops. The control, i.e., enhancement or suppression, of these thermal patterns at the drop interface by means of ambient temperature and relative humidity is quantified and reported.

  20. Ambient temperature-independent dual-band mid-infrared radiation thermometry.

    Science.gov (United States)

    Lü, You; He, Xin; Wei, Zhong-Hui; Sun, Zhi-Yuan; Chang, Song-Tao

    2016-03-20

    For temperature measurements of targets at low temperatures, dual-band radiation thermometry using mid-infrared detectors has been investigated extensively. However, the accuracy is greatly affected by the reflected ambient radiation and stray radiation, which depend on the ambient temperature. To ensure measurement accuracy, an improved dual-band measurement model is established by considering the reflected ambient radiation and the stray radiation. The effect of ambient temperature fluctuation on temperature measurement is then further analyzed in detail. Experimental results of measuring a gray-body confirm that the proposed method yields high accuracy at varying ambient temperatures. This method provides a practical approach to remove the effect of ambient temperature fluctuations on temperature measurements.

  1. Habitat type and ambient temperature contribute to bill morphology.

    Science.gov (United States)

    Luther, David; Greenberg, Russell

    2014-03-01

    Avian bills are iconic structures for the study of ecology and evolution, with hypotheses about the morphological structure of bills dating back to Darwin. Several ecological and physiological hypotheses have been developed to explain the evolution of the morphology of bill shape. Here, we test some of these hypotheses such as the role of habitat, ambient temperature, body size, intraspecific competition, and ecological release on the evolution of bill morphology. Bill morphology and tarsus length were measured from museum specimens of yellow warblers, and grouped by habitat type, sex, and subspecies. We calculated the mean maximum daily temperature for the month of July, the hottest month for breeding specimens at each collecting location. Analysis of covariance models predicted total bill surface area as a function of sex, habitat type, body size, and temperature, and model selection techniques were used to select the best model. Habitat, mangrove forests compared with inland habitats, and climate had the largest effects on bill size. Coastal wetland habitats and island populations of yellow warblers had similar bill morphology, both of which are larger than mainland inland populations. Temperate but not tropical subspecies exhibited sexual dimorphism in bill morphology. Overall, this study provides evidence that multiple environmental factors, such as temperature and habitat, contribute to the evolution of bill morphology.

  2. Hydrogen Storage at Ambient Temperature by the Spillover Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Yang , Ralph T.

    2011-02-04

    The goal of this project was to develop new nanostructured sorbent materials, using the hydrogen spillover mechanism that could meet the DOE 2010 system targets for on-board vehicle hydrogen storage. Hydrogen spillover may be broadly defined as the transport (i.e., via surface diffusion) of dissociated hydrogen adsorbed or formed on a first surface onto another surface. The first surface is typically a metal (that dissociates H2) and the second surface is typically the support on which the metal is doped. Hydrogen spillover is a well documented phenomenon in the catalysis literature, and has been known in the catalysis community for over four decades, although it is still not well understood.1, 2 Much evidence has been shown in the literature on its roles played in catalytic reactions. Very little has been studied on hydrogen storage by spillover at ambient temperature. However, it is also known to occur at such temperature, e.g., direct evidence has been shown for spillover on commercial fuel-cell, highly dispersed Pt/C, Ru/C and PtRu/C catalysts by inelastic neutron scattering.3 To exploit spillover for storage, among the key questions are whether spillover is reversible at ambient temperature and if the adsorption (refill) and desorption rates at ambient temperature are fast enough for automotive applications. In this project, we explored new sorbents by using a transition metal (e.g., Pt, Ru, Pd and Ni) as the H2 dissociation source and sorbents as the hydrogen receptor. The receptors included superactivated carbons (AX-21 and Maxsorb), metal organic frameworks (MOFs) and zeolites. Different metal doping methods have been used successfully to achieve high metal dispersion thereby allowing significant spillover enhancements, as well as a bridging technique used for bridging to MOFs. Among the metals tested, Pt is the hardest to achieve high metal dispersion (and consequently spillover) while Ru is the easiest to disperse. By properly dispersing Pt on

  3. Ambient temperature affects the temperature threshold for TRPM8 activation through interaction of phosphatidylinositol 4,5-bisphosphate.

    Science.gov (United States)

    Fujita, Fumitaka; Uchida, Kunitoshi; Takaishi, Masayuki; Sokabe, Takaaki; Tominaga, Makoto

    2013-04-03

    Cold sensation is an important and fundamental sense for animals and it is known to be affected by ambient temperature. Transient Receptor Potential Melastatin 8 (TRPM8), a nonselective cation channel expressed in a subset of peripheral afferent fibers, acts as a cold sensor, having an activation threshold of ∼28°C. Although the cold temperature threshold of TRPM8 is affected by menthol or pH, ambient temperature has not been reported to affect it. Because the cold temperature threshold was thought to be unchanged by alterations in ambient temperature, the relativity of temperature sensing in different ambient temperatures could not be understood at the level of molecular function of thermosensitive TRP channels. Here, we show that ambient temperature changed the temperature threshold for activation of human and rat TRPM8 in a heterologous expression system and cold responses in mouse DRG neurons. Moreover, reducing the level of cellular phosphatidylinositol 4,5-bisphosphate (PIP2) attenuated changes in the cold temperature threshold after alterations in ambient temperature. A single amino acid mutation at position 1008 in the C terminus of TRPM8 (arginine to glutamine) also attenuated changes in the cold temperature threshold induced by ambient temperature. These findings suggest that ambient temperature does affect the temperature threshold for TRPM8 activation through interaction of PIP2.

  4. Thermoelectric Energy Harvesting from Transient Ambient Temperature Gradients

    Science.gov (United States)

    Moser, André; Erd, Metin; Kostic, Milos; Cobry, Keith; Kroener, Michael; Woias, Peter

    2012-06-01

    We examine a thermoelectric harvester that converts electrical energy from the naturally occurring temperature difference between ambient air and large thermal storage capacitors such as building walls or the soil. For maximum power output, the harvester design is implemented in two steps: source matching of the thermal and electrical interfaces to the energy source (system level) followed by load matching of the generator to these interfaces (subsystem level). Therefore, we measure thermal source properties such as the temperature difference, the air velocity, and the cutoff frequency in two application scenarios (road tunnel and office building). We extend a stationary model of the harvester into the time domain to account for transient behavior of the source. Based on the model and the source measurements, we perform the source and load matching. The resulting harvester consists of a pin fin heat sink with a thermal resistance of 6.2 K/W and a cutoff frequency 2.5 times greater than that of the source, a thermoelectric generator, and a DC/DC step-up converter starting at a total temperature difference of only Δ T = 1.2 K. In a final road tunnel field test, this optimized harvester converts 70 mJ of electrical energy per day without any direct solar irradiation. The energy provided by the harvester enables 415 data transmissions from a wireless sensor node per day.

  5. Thermoelectric energy harvesting from small ambient temperature transients

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Andre

    2012-07-01

    Wireless sensor networks (WSNs) represent a key technology, used, for instance, in structural health monitoring, building automation systems, or traffic surveillance. Supplying power to a network of spatially distributed sensor nodes, especially at remote locations, is a large challenge: power grids are reliable but costly to install, whereas batteries provide a high flexibility in the installation but have a limited lifetime. This dilemma can be overcome by micro energy harvesting which offers both: reliability and flexibility. Micro energy harvesters are able to convert low grade ambient energy into useful electrical energy and thus provide power for wireless sensor networks or other electronic devices - in-situ, off-grid, and with an almost unlimited lifetime. Thermal energy is an omnipresent source of ambient energy: The day-night-cycle of the sun causes a temperature variation in the ambient air as well as arbitrary solids (soil, building walls, etc.). Unlike the air, solids have a large thermal inertia which dampens the temperature variation. This physical process leads to a temperature difference {Delta}T = T{sub air} - T{sub solid} between air and solid that can be converted directly into electrical energy by a thermoelectric generator (TEG). Thermal and electrical interfaces are necessary to connect the TEG to the thermal energy source (T{sub air}, T{sub solid}) and the electrical load (WSN). Reliable operation of the WSN may only be ensured if the harvester provides sufficient electrical energy, i.e. operates at its maximum power point. The goal of this thesis is to study, design, and test thermoelectric harvesters generating electrical energy from small ambient temperature transients in order to self-sufficiently power a WSN. Current research into thermoelectric energy harvesting, especially analytical modeling and application in the field are treated insufficiently. Therefore, a time-dependent analytical model of the harvester's output power is set

  6. A Novel RAFT Polymerization under UV Radiation at Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    Nianfa Yang; Lican Lu; Yuanli Cai

    2005-01-01

    @@ 1Introduction Reversible Addition Fragmentation chain Transfer (RAFT) polymerization has become a highly versatile technique for the controlled/"living" radical polymerization of a wide range of monomers under various conditions[1,2]. The RAFT polymerization was carried out using a dithiocarboxylate or trithiocarbonate as a Chain Transfer Agent (CTA), which mediates the growing chain radicals via an equilibrium[1,2]. From both academic and industrial standpoints, it is clearly desirable to develop a RAFT process under mild conditions. Rizzardo, et al [3] and McCormick's group[4] have respectively reported RAFT polymerization using conventional radical initiators at ambient temperature by adjusting the structure of CTA. The RAFT Polymerization initiated by γ-radiation has also reported recently[5]. Quinn, et al [6] have reported the RAFT polymerization under UV radiation using CTA as the source of primary radicals at 42 ℃, which was well controlled at low conversions (below 20% ) but less controlled at higher conversions (over 20% ) due to the photolysis of CTA residues under UV radiation.

  7. ambiental

    Directory of Open Access Journals (Sweden)

    Roque Leal Salcedo

    2008-01-01

    Full Text Available El derecho internacional ambiental es un conocimiento de carácter transversal, que entre otras consideraciones refleja las preocupaciones de la sociedad por la implementación de un modelo de desarrollo sustentable para el respeto a las reglas del medio natural que garantizan la integridad y renovación de los sistemas naturales. El presente artículo enfoca esta visión a través del análisis de material documental revisado, entre ellos tratados internacionales que permiten distinguir el desarrollo del derecho internacional ambiental y el papel de Organización de las Naciones Unidas (ONU, en el propósito común del derecho individual y colectivo de disfrutar de una vida, un ambiente seguro, sano y ecológicamente equilibrado. En función a estas disertaciones las consideraciones finales exponen parte de la visión que ha estructurado la ONU y que representan un aporte considerable en el fomento de la conciencia mundial sobre la necesidad de establecer vínculos entre las naciones para el continuo desarrollo de esta rama del derecho.

  8. The dependence of surface temperature on IGBTs load and ambient temperature

    Science.gov (United States)

    Alexander, Čaja; Marek, Patsch

    2015-05-01

    Currently, older power electronics and electrotechnics are improvement and at the same time developing new and more efficient devices. These devices produce in their activities a significant part of the heat which, if not effectively drained, causing damage to these elements. In this case, it is important to develop new and more efficient cooling system. The most widespread of modern methods of cooling is the cooling by heat pipe. This contribution is aimed at cooling the insulated-gate bipolar transistor (IGBT) elements by loop heat pipe (LHP). IGBTs are very prone to damage due to high temperatures, and therefore is the important that the surface temperature was below 100°C. It was therefore created a model that examined what impact of surface temperature on the IGBT element and heat removal at different load and constant ambient temperature.

  9. The dependence of surface temperature on IGBTs load and ambient temperature

    Directory of Open Access Journals (Sweden)

    Alexander Čaja

    2015-01-01

    Full Text Available Currently, older power electronics and electrotechnics are improvement and at the same time developing new and more efficient devices. These devices produce in their activities a significant part of the heat which, if not effectively drained, causing damage to these elements. In this case, it is important to develop new and more efficient cooling system. The most widespread of modern methods of cooling is the cooling by heat pipe. This contribution is aimed at cooling the insulated-gate bipolar transistor (IGBT elements by loop heat pipe (LHP. IGBTs are very prone to damage due to high temperatures, and therefore is the important that the surface temperature was below 100°C. It was therefore created a model that examined what impact of surface temperature on the IGBT element and heat removal at different load and constant ambient temperature.

  10. A method to measure internal stray radiation of cryogenic infrared imaging systems under various ambient temperatures

    Science.gov (United States)

    Tian, Qijie; Chang, Songtao; Li, Zhou; He, Fengyun; Qiao, Yanfeng

    2017-03-01

    The suppression level of internal stray radiation is a key criterion for infrared imaging systems, especially for high-precision cryogenic infrared imaging systems. To achieve accurate measurement for internal stray radiation of cryogenic infrared imaging systems under various ambient temperatures, a measurement method, which is based on radiometric calibration, is presented in this paper. First of all, the calibration formula is deduced considering the integration time, and the effect of ambient temperature on internal stray radiation is further analyzed in detail. Then, an approach is proposed to measure the internal stray radiation of cryogenic infrared imaging systems under various ambient temperatures. By calibrating the system under two ambient temperatures, the quantitative relation between the internal stray radiation and the ambient temperature can be acquired, and then the internal stray radiation of the cryogenic infrared imaging system under various ambient temperatures can be calculated. Finally, several experiments are performed in a chamber with controllable inside temperatures to evaluate the effectiveness of the proposed method. Experimental results indicate that the proposed method can be used to measure internal stray radiation with high accuracy at various ambient temperatures and integration times. The proposed method has some advantages, such as simple implementation and the capability of high-precision measurement. The measurement results can be used to guide the stray radiation suppression and to test whether the internal stray radiation suppression performance meets the requirement or not.

  11. Influence of the ambient air temperature on the electrical contact reliability of electromagnetic relay

    Institute of Scientific and Technical Information of China (English)

    YAO Fang; ZHENG Jian-rong; HUANG Zhang-wu

    2007-01-01

    The dynamic contact resistances of HH52P electromagnetic relays are measured under different ambient air temperature. Their diagnostic parameters are extracted and determined. It is found that the ambient air temperature obviously influences some parameters. In order to research its influence on the electrical contact reliability of electromagnetic relay, the statistic analysis is applied to study the static contact resistance, the max of the dynamic contact resistance and the bounce time. It is found that the ambient air temperature regularly influences the three parameters. Thoroughly, the phenomenon is studied and analyzed in the point of material science so as to probe into the essential matter of it.

  12. Ambient Temperature Based Thermal Aware Energy Efficient ROM Design on FPGA

    DEFF Research Database (Denmark)

    Saini, Rishita; Bansal, Neha; Bansal, Meenakshi

    2015-01-01

    Thermal aware design is currently gaining importance in VLSI research domain. In this work, we are going to design thermal aware energy efficient ROM on Virtex-5 FPGA. Ambient Temperature, airflow, and heat sink profile play a significant role in thermal aware hardware design life cycle. Ambient...

  13. Influence of ambient temperature and diurnal temperature range on incidence of cardiac arrhythmias

    Science.gov (United States)

    Kim, Jayeun; Kim, Ho

    2016-08-01

    We investigated the association between ambient temperature and diurnal temperature range (DTR) and the exacerbation of arrhythmia symptoms, using data from 31,629 arrhythmia-related emergency department (ED) visits in Seoul, Korea. Linear regression analyses with allowances for over-dispersion were applied to temperature variables and ED visits, adjusted for various environmental factors. The effects were expressed as percentage changes in the risk of arrhythmia-related ED visits up to 5 days later, with 95 % confidence intervals (CI), per 1 °C increase in DTR and 1 °C decrease in mean temperature. The overall risk of ED visits increased by 1.06 % (95 % CI 0.39 %, 1.73 %) for temperature and by 1.84 % (0.34, 3.37 %) for DTR. A season-specific effect was detected for temperature during both fall (1.18 % [0.01, 2.37 %]) and winter (0.87 % [0.07, 1.67 %]), and for DTR during spring (3.76 % [0.34, 7.29 %]). Females were more vulnerable, with 1.57 % [0.56, 2.59 %] and 3.84 % [1.53, 6.20 %] for the changes in temperature and DTR, respectively. An age-specific effect was detected for DTR, with 3.13 % [0.95, 5.36 %] for age ≥ 65 years, while a greater increased risk with temperature decrease was observed among those aged arrhythmias depended more on the change in DTR (4.72 % [0.37, 9.26 %]). These findings provide evidence that low-temperature and elevated DTR influence the occurrence of arrhythmia exacerbations or symptoms, suggesting a possible strategy for reducing risk by encouraging vulnerable populations to minimize exposure.

  14. Significance and influence of the ambient temperature as a rate factor of steel reinforcement corrosion

    Indian Academy of Sciences (India)

    V Živica

    2002-10-01

    The rate of corrosion of reinforcement being an electrochemical process, undoubtedly is dependent even on the level of the ambient temperature. Therefore, the ambient temperature seems to be an important factor of the corrosion rate and the durability of the reinforced concrete structures in aggressive environment. The present data on the influence and significance of the ambient temperature in the process of corrosion of reinforcement of the reinforced structures are surprisingly limited and poor. It seems that it is supposed to be a simple increase of corrosion rate when the ambient temperature is increased. The lack of information was a motivation for the present study. It was aimed at the experimental research of the influence of the increase of the ambient temperature on the rate of chloride induced corrosion of steel reinforcement. The results obtained show that the influence of the studied factor is more complex showing an acceleration effect till a temperature of 40°C diversified by the inhibition effects with further increase of the ambient temperature.

  15. Influence of the Ambient Temperature, to the Hydrogen Fuel Cell Functioning

    Directory of Open Access Journals (Sweden)

    POPOVICI Ovidiu

    2012-10-01

    Full Text Available The reversible fuel cell can be used to produce hydrogen. The hydrogen is further the chemical energy source to produce electrical energy using the fuel cell. The ambient temperature will influence theparameters of the hydrogen fuel cell.

  16. Thiamine hydrochloride: An efficient catalyst for one-pot synthesis of quinoxaline derivatives at ambient temperature

    Indian Academy of Sciences (India)

    Omprakash B Pawar; Fulchand R Chavan; Venkat S Suryawanshi; Vishnu S Shinde; Narayan D Shinde

    2013-01-01

    Quinoxaline derivatives have been synthesized in high to excellent yields in the presence of thiamine hydrochloride (VB1) as an inexpensive, non-toxic and metal ion free catalyst at ambient temperature.

  17. Effects of the ambient temperature on the airflow across a Caucasian nasal cavity.

    Science.gov (United States)

    Burgos, M A; Sanmiguel-Rojas, E; Martín-Alcántara, A; Hidalgo-Martínez, M

    2014-03-01

    We analyse the effects of the air ambient temperature on the airflow across a Caucasian nasal cavity under different ambient temperatures using CFD simulations. A three-dimensional nasal model was constructed from high-resolution computed tomography images for a nasal cavity from a Caucasian male adult. An exhaustive parametric study was performed to analyse the laminar-compressible flow driven by two different pressure drops between the nostrils and the nasopharynx, which induced calm breathing flow rates ࣈ 5.7 L/min and ࣈ 11.3 L/min. The inlet air temperature covered the range - 10(o) C ⩽ To ⩽50(o) C. We observed that, keeping constant the wall temperature of the nasal cavity at 37(o) C, the ambient temperature affects mainly the airflow velocity into the valve region. Surprisingly, we found an excellent linear relationship between the ambient temperature and the air average temperature reached at different cross sections, independently of the pressure drop applied. Finally, we have also observed that the spatial evolution of the mean temperature data along the nasal cavity can be collapsed for all ambient temperatures analysed with the introduction of suitable dimensionless variables, and this evolution can be modelled with the help of hyperbolic functions, which are based on the heat exchanger theory.

  18. Study of the Recombination of H2 and O2 at Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The hydrophobic catalysts was developed at Chalk River Nuclear Laboratories and was used in the recombiner operated at ambient conditions. The advantage of operating a recombiner at ambient temperature were recognized by several researchers. It is clear that significant savings can be realized if the recombiner is operated at ambient temperature without the need for costly heaters and coolers. And the process is safer and more uncomplicated than conventional processes.The experimental conditions as followings: carrier gas is Ar; concentration of H2 is 1%;

  19. Impact of ambient temperature on spring-based relative gravimeter measurements

    Science.gov (United States)

    Fores, B.; Champollion, C.; Moigne, N. Le; Chery, J.

    2016-10-01

    In this paper, we investigate the impact of ambient temperature changes on the gravity reading of spring-based relative gravimeters. Controlled heating experiments using two Scintrex CG5 gravimeters allowed us to determine a linear correlation (R 2> 0.9) between ambient temperature and gravity variations. The relation is stable and constant for the two CG5 we used: -5 nm/s2/° C. A linear relation is also seen between gravity and residual sensor temperature variations (R 2> 0.75), but contrary to ambient temperature, this relation is neither constant over time nor similar between the two instruments. The linear correction of ambient temperature on the controlled heating time series reduced the standard deviation at least by a factor of 2, to less than 10 nm/s2 . The laboratory results allowed for reprocessing the data gathered on a field survey that originally aimed to characterize local hydrological heterogeneities on a karstic area. The correction of two years of monthly CG5 measurements from ambient temperature variations halved the standard deviation (from 62 to 32 nm/s2 ) and led us to a better hydrological interpretation. Although the origin of this effect is uncertain, we suggest that an imperfect control of the sensor temperature may be involved, as well as a change of the properties of an electronic component.

  20. Comparability of tympanic and oral mercury thermometers at high ambient temperatures

    Directory of Open Access Journals (Sweden)

    Chue Amy L

    2012-07-01

    Full Text Available Abstract Background Body temperature can be measured in seconds with tympanic thermometers as opposed to minutes with mercury ones. The aim of this study was to compare tympanic and oral mercury thermometer measurements under high ambient field temperatures. Results Tympanic temperature (measured thrice by 3 operators was compared to oral temperature measured once with a mercury-in-glass thermometer in 201 patients (aged ≥5 years, on the Thai-Myanmar border. Ambient temperature was measured with an electronic thermo-hygrometer. Participants had a mean [min-max] age of 27 [5–60] years and 42% (84 were febrile by oral thermometer. The mean difference in the mercury and tympanic temperature measurement for all observers/devices was 0.09 (95%CI 0.07-0.12°C and intra-class correlation for repeat tympanic measurements was high (≥0.97 for each observer. Deviations in tympanic temperatures were not related to ambient temperature. Conclusion Clinically significant differences were not observed between oral and tympanic temperature measurements at high ambient temperatures in a rural tropical setting.

  1. Effects of ambient oxygen concentration on soot temperature and concentration for biodiesel and diesel spray combustion

    KAUST Repository

    Zhang, Ji

    2015-06-01

    Ambient oxygen concentration, a key variable directly related to exhaust gas recirculation (EGR) levels in diesel engines, plays a significant role in particulate matter (PM) and nitrogen oxides (NOx) emissions. The utilization of biodiesel in diesel engines has been investigated over the last decades for its renewable characteristics and lower emissions compared to diesel. In an earlier work, we demonstrated that the soot temperature and concentration of biodiesel were lower than diesel under regular diesel engine conditions without EGR. Soot concentration was quantified by a parameter called KL factor. As a continuous effort, this paper presents an experimental investigation of the ambient oxygen concentration on soot temperature and KL factor during biodiesel and diesel spray combustion. The experiment was implemented in a constant volume chamber system, where the ambient oxygen concentration varied from 21 to 10% and the ambient temperature was kept to 1,000 K. A high speed two-color pyrometry technique was used to measure transient soot temperature and the KL factor of the spray flame. The soot temperature of biodiesel is found to be lower than that of diesel under the same conditions, which follows the same trend from our previous results found when the ambient temperature changes to 21% oxygen conditions. A reduction in ambient oxygen concentration generally reduces the soot temperature for both fuels. However, this is a complicated effect on soot processes as the change of oxygen concentration greatly affects the balance between soot formation and oxidation. The KL factor is observed to be the highest at 12% O2 for diesel and 18% O2 for biodiesel, respectively. On the other hand, the 10% O2 condition shows the lowest KL factor for both fuels. These results can provide quantitative experimental evidences to optimize the ambient oxygen concentration for diesel engines using different fuels for better emissions characteristics. © 2014 American Society of

  2. Type 2 diabetes, but not obesity, prevalence is positively associated with ambient temperature.

    Science.gov (United States)

    Speakman, John R; Heidari-Bakavoli, Sahar

    2016-08-01

    Cold exposure stimulates energy expenditure and glucose disposal. If these factors play a significant role in whole body energy balance, and glucose homeostasis, it is predicted that both obesity and type 2 diabetes prevalence would be lower where it is colder. Previous studies have noted connections between ambient temperature and obesity, but the direction of the effect is confused. No previous studies have explored the link of type 2 diabetes to ambient temperature. We used county level data for obesity and diabetes prevalence across the mainland USA and matched this to county level ambient temperature data. Average ambient temperature explained 5.7% of the spatial variation in obesity and 29.6% of the spatial variation in type 2 diabetes prevalence. Correcting the type 2 diabetes data for the effect of obesity reduced the explained variation to 26.8%. Even when correcting for obesity, poverty and race, ambient temperature explained 12.4% of the variation in the prevalence of type 2 diabetes, and this significant effect remained when latitude was entered into the model as a predictor. When obesity prevalence was corrected for poverty and race the significant effect of temperature disappeared. Enhancing energy expenditure by cold exposure will likely not impact obesity significantly, but may be useful to combat type 2 diabetes.

  3. The effect of ambient temperature on gross-efficiency in cycling

    NARCIS (Netherlands)

    Hettinga, F.J.; Koning, J.J. de; Vrijer, A. de; Wüst, R.C.I.; Daanen, H.A.M.; Foster, C.

    2007-01-01

    Time-trial performance deteriorates in the heat. This might potentially be the result of a temperature-induced decrease in gross-efficiency (GE). The effect of high ambient temperature on GE during cycling will be studied, with the intent of determining if a heat-induced change in GE could account f

  4. Experimental and casework validation of ambient temperature corrections in forensic entomology.

    Science.gov (United States)

    Johnson, Aidan P; Wallman, James F; Archer, Melanie S

    2012-01-01

    This paper expands on Archer (J Forensic Sci 49, 2004, 553), examining additional factors affecting ambient temperature correction of weather station data in forensic entomology. Sixteen hypothetical body discovery sites (BDSs) in Victoria and New South Wales (Australia), both in autumn and in summer, were compared to test whether the accuracy of correlation was affected by (i) length of correlation period; (ii) distance between BDS and weather station; and (iii) periodicity of ambient temperature measurements. The accuracy of correlations in data sets from real Victorian and NSW forensic entomology cases was also examined. Correlations increased weather data accuracy in all experiments, but significant differences in accuracy were found only between periodicity treatments. We found that a >5°C difference between average values of body in situ and correlation period weather station data was predictive of correlations that decreased the accuracy of ambient temperatures estimated using correlation. Practitioners should inspect their weather data sets for such differences.

  5. Coesite Formation at Ambient Pressure and Low Temperatures

    Directory of Open Access Journals (Sweden)

    J. R. Martínez

    2008-01-01

    Full Text Available Partial crystallization of silica xerogel in the form of coesite has been obtained at low-pressure conditions and temperatures of ∼565∘C, in samples containing chlorophyll aggregates dispersed in amorphous silica. Silica xerogel samples were prepared by the sol-gel method using an ethanol:H2O:TEOS molar ratio of 4:11.6:1 and loaded with extracts from frozen spinach leaves. The silica xerogel microstructure of the powders was studied as a function of annealing temperature. It was found that partial crystallization of the glass matrix in the form of coestite was obtained at lower pressure than those specified by the phase diagram. Chlorophyll aggregates were added to the starting solutions which, upon thermal treatments, form small colloidal particles in the glass matrix. The presence of coesite is corroborated by the Rietveld refinement method.

  6. Creep testing of nodular iron at ambient and elevated temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Martinsson, Aasa; Andersson-Oestling, Henrik C.M.; Seitisleam, Facredin; Wu, Rui; Sandstroem, Rolf (Swerea KIMAB AB, Stockholm (Sweden))

    2010-12-15

    The creep strain at room temperature, 100 and 125 deg C has been investigated for the ferritic nodular cast iron insert intended for use as the load-bearing part of canisters for long term disposal of spent nuclear fuel. The microstructure consisted of ferrite, graphite nodules of different sizes, compacted graphite and pearlite. Creep tests have been performed for up to 41,000 h. The specimens were cut out from material taken from two genuine inserts, I30 and I55. After creep testing, the specimens from the 100 deg C tests were hardness tested and a metallographic examination was performed. Creep strains at all temperatures appear to be logarithmic, and accumulation of creep strain diminishes with time. The time dependence of the creep strain is consistent to the W-model for primary creep. During the loading plastic strains up to 1% appeared. The maximum recorded creep strain after the loading phase was 0.025%. This makes the creep strains technically insignificant. Acoustic emission recordings during the loading of the room temperature tests showed no sounds or other evidence of microcracking during the loading phase. There is no evidence that the hardness or the graphite microstructure changed during the creep tests

  7. Splicing-related genes are alternatively spliced upon changes in ambient temperatures in plants

    Science.gov (United States)

    Bucher, Johan; Lammers, Michiel; Busscher-Lange, Jacqueline; Bonnema, Guusje; Rodenburg, Nicole; Proveniers, Marcel C. G.; Angenent, Gerco C.

    2017-01-01

    Plants adjust their development and architecture to small variations in ambient temperature. In a time in which temperatures are rising world-wide, the mechanism by which plants are able to sense temperature fluctuations and adapt to it, is becoming of special interest. By performing RNA-sequencing on two Arabidopsis accession and one Brassica species exposed to temperature alterations, we showed that alternative splicing is an important mechanism in ambient temperature sensing and adaptation. We found that amongst the differentially alternatively spliced genes, splicing related genes are enriched, suggesting that the splicing machinery itself is targeted for alternative splicing when temperature changes. Moreover, we showed that many different components of the splicing machinery are targeted for ambient temperature regulated alternative splicing. Mutant analysis of a splicing related gene that was differentially spliced in two of the genotypes showed an altered flowering time response to different temperatures. We propose a two-step mechanism where temperature directly influences alternative splicing of the splicing machinery genes, followed by a second step where the altered splicing machinery affects splicing of downstream genes involved in the adaptation to altered temperatures. PMID:28257507

  8. Effect of Ambient Temperature on Performance of Grid-Connected Inverter Installed in Thailand

    Directory of Open Access Journals (Sweden)

    Kamonpan Chumpolrat

    2014-01-01

    Full Text Available The effects of temperature on performance of a grid-connected inverter, and also on a photovoltaic (PV system installed in Thailand have been investigated. It was found that the maximum efficiency of the inverter showed 2.5% drop when ambient temperature was above 37°C. The inverter performed efficiently in November and December, the months of high irradiance, and monthly average ambient temperature of lower than 35°C, allowing relatively high system performance ratio in this period. Our results show that high temperature provides negative impacts not only on the PV modules, but also on the performance of the inverter. Thus, the effect of temperature on the inverter efficiency should be taken into account when predicting energy yield or analyzing losses of the PV systems—especially in high temperature regions.

  9. Influence of Ambient Temperature on Nanosecond and Picosecond Laser-Induced Bulk Damage of Fused Silica

    Directory of Open Access Journals (Sweden)

    L. Yang

    2014-01-01

    Full Text Available The nanosecond (ns and picosecond (ps pulsed laser-induced damage behaviors of fused silica under cryogenic and room temperature have been investigated. The laser-induced damage threshold (LIDT and damage probability are used to understand the damage behavior at different ambient temperatures. The results show that the LIDTs for both ns and ps slightly increased at cryogenic temperature compared to that at room temperature. Meanwhile, the damage probability has an inverse trend; that is, the damage probability at low temperature is smaller than that at room temperature. A theoretical model based on heated crystal lattice is well consistent with the experimental results.

  10. Impact of Seasonal Variant Temperatures and Laboratory Room Ambient Temperature on Mortality of Rats with Ischemic Brain Injury

    Science.gov (United States)

    Gopalakrishanan, Sivakumar; Babu, Mg. Ramesh; Thangarajan, Rajesh; Punja, Dhiren; Jaganath, Vidyadhara Devarunda; Kanth, Akriti B.; Rao, Mohandas

    2016-01-01

    Introduction A popular rat model for hypoperfusion ischemic brain injury is bilateral common carotid artery occlusion (BCCAO). BCCAO surgery when performed in varying geographical locations and during different seasons of the year is reported to have variable mortality rates. Studies have also documented the diminishing influence of Ketamine-Xylazine (KT-XY) on thermoregulatory functions in rodents. Aim To explore the impact of seasonal variant temperatures and laboratory room ambient temperatures on mortality of rats following BCCAO surgery. Materials and Methods The study has two parts: 1 The first part is an analysis of a three year retrospective data to explore the association between the geographical season (hot summer and cold winter) induced laboratory room ambient temperature variations and the mortality rate in KT-XY anaesthetized BCCAO rats. 2. The second part investigated the effect of conditioned laboratory room ambient temperature (CAT) (23-250C) in KT-XY anaesthetized BCCAO group of rats. Rats were divided into 4 groups(n =8/group) as-Normal control, BCCAO and Sham BCCAO where they were all exposed to unconditioned ambient temperature (UCAT) during their surgery and postoperative care. And finally fourth group rats exposed to CAT during the BCCAO surgery and postoperative care. Results Pearson’s chi-square test indicates a significantly high association (p<0.006) between post-BCCAO mortality and hot season of the year. CAT during the hot season reduced the mortality rate (24% less) in post- BCCAO rats compared to the rats of UCAT. Conclusion Despite seasonal variations in temperature, conditioning the laboratory room ambient temperatures to 23–250C, induces hypothermia in KT-XY anaesthetized ischemic brain injured rodents and improves their survival rate. PMID:27190796

  11. Quantum Coherent Dynamics at Ambient Temperature in Photosynthetic Molecules

    CERN Document Server

    Walters, Zachary B

    2011-01-01

    Photosynthetic antenna complexes are responsible for absorbing energy from sunlight and transmitting it to remote locations where it can be stored. Recent experiments have found that this process involves long-lived quantum coherence between pigment molecules, called chromophores, which make up these complexes. Expected to decay within 100 fs at room temperature, these coherences were instead found to persist for picosecond time scales, despite having no apparent isolation from the thermal environment of the cell. This paper derives a quantum master equation which describes the coherent evolution of a system in strong contact with a thermal environment. Conditions necessary for long coherence lifetimes are identified, and the role of coherence in efficient energy transport is illuminated. Static spectra and exciton transfer rates for the PE545 complex of the cryptophyte algae CS24 are calculated and shown to have good agreement with experiment.

  12. Dependence of electric strength on the ambient temperature

    Energy Technology Data Exchange (ETDEWEB)

    Čaja, Alexander, E-mail: alexander.caja@fstroj.uniza.sk, E-mail: patrik.nemec@fstroj.uniza.sk, E-mail: milan.malcho@fstroj.uniza.sk; Nemec, Patrik, E-mail: alexander.caja@fstroj.uniza.sk, E-mail: patrik.nemec@fstroj.uniza.sk, E-mail: milan.malcho@fstroj.uniza.sk; Malcho, Milan, E-mail: alexander.caja@fstroj.uniza.sk, E-mail: patrik.nemec@fstroj.uniza.sk, E-mail: milan.malcho@fstroj.uniza.sk [University of Žilina, Faculty of Mechanical Engineering, Department of Power Engeneering, Univerzitná 1, 010 26 Žilina (Slovakia)

    2014-08-06

    At present, the volume concentration of electronic components in their miniaturization to different types of microchips and increasing their performance raises the problem of cooling such elements due to the increasing density of heat flow of heat loss. Compliance with safe operating temperature of active semiconductor element is very closely related to the reliability and durability not only components, but also the entire device. Often it is also necessary to electrically isolate the unit from the side of the cooler air. Cooling demand by natural convection is typical for applications with high operating reliability. To the reliability of the system for removing heat loss increased, it is necessary to minimize need to use the mechanically or electrically powered elements, such as circulation pumps or fans. Experience to date with applications of heat pipe in specific systems appears to be the most appropriate method of cooling.

  13. Influence of the ambient temperature during heat pipe manufacturing on its function and heat transport ability

    Directory of Open Access Journals (Sweden)

    Čaja A.

    2014-03-01

    Full Text Available Heat pipe is heat transfer device working at a minimum temperature difference of evaporator and condenser. Operating temperature of the heat pipe determine by properties of the working substance and pressure achieved during production. The contribution is focused on the determining the effect of the initial surrounding temperature where the heat pipe is manufactured and on the obtaining performance characteristics produced heat pipes in dependence of manufacturing temperature. Generally hold, that the boiling point of the working liquid decrease with decreasing ambient pressure. Based on this can be suppose that producing of lower ambient temperature during heat pipe manufacturing, will create the lower pressure, the boiling point of the working fluid will lower too and the heat pipe should be better performance characteristics.

  14. Ambient temperature cured TiB2 cathode coating for aluminum electrolysis

    Institute of Scientific and Technical Information of China (English)

    赖延清; 李庆余; 杨建红; 李劼

    2003-01-01

    The concept of ambient temperature curable TiB2 cathode coating was put forward, and the ambient temperature curable TiB2 cathode coating was prepared successfully. Differing from the previous TiB2 cathode coating solidified approximately at 200 ℃,the ambient temperature curable TiB2 cathode coating can be solidified at room temperature, so the heating equipment is not necessary, which simplifies the preparation process and facilitates the industrial application of TiB2 cathode coating. Many kinds of resin and curing agent were investigated. On the above-mentioned basis, the ambient temperature curable TiB2 cathode coating was prepared with furan resin 5 500 mixed with complex resins B as carbon binder and DXG1 as curing agent in 24 h. The results show that the properties of prepared coating are excellent, the electrical resistivity is 29.8 μΩ*m, the compressive strength is 33.6 MPa, which are all better than the relevant properties of partially graphitized cathode carbon block for aluminum electrolysis prescribed by the GB 8744-88. SEM morphologies show that the section morphology of the TiB2 coating is unaltered during the electrolysis test, the TiB2 coating can be used in aluminum electrolysis industry to save energy and prolong the life of aluminum electrolysis cell.

  15. Effect of ambient temperature and light intensity on physiological reactions of heavy broiler chickens.

    Science.gov (United States)

    Olanrewaju, H A; Purswell, J L; Collier, S D; Branton, S L

    2010-12-01

    The effects of ambient temperature, light intensity, and their interaction on blood acid-base balance, metabolites, and electrolytes in broiler chickens under environmentally controlled conditions were examined in 2 trials. The experiment consisted of a factorial arrangement of treatments in a randomized complete block design. The 9 treatments consisted of 3 levels of temperatures (low = 15.6°C; moderate = 21.1°C; high = 26.7°C) from 21 to 56 d of age and 3 levels of light intensities (0.5, 3.0, 20 lx) from 8 to 56 d of age at 50% RH. A total of 540 Ross 708 chicks were randomly distributed into 9 environmentally controlled chambers (30 male and 30 female chicks/chamber) at 1 d of age. Feed and water were provided ad libitum. Venous blood samples were collected on d 21 (baseline), 28, 42, and 56. High ambient temperature significantly (P ≤ 0.05) reduced BW, partial pressure of CO(2), bicarbonate, hematocrit, hemoglobin, K(+), and Na(+) along with significantly (P ≤ 0.05) elevated pH level, Cl(-), glucose, osmolality, and anion gap concentrations. Partial pressure of O(2) was slightly increased in response to increased ambient temperature. There was no effect of light intensity on most of the blood variables examined. Acid-base regulation during high ambient temperature and light intensity exposure did not deteriorate despite a lower partial pressure of CO(2), which consequently increased blood pH because of a compensatory decrease in HCO(3)(-) concentration. Plasma corticosterone was not affected by temperature, light intensity, or their interaction. These results indicate that continuous exposure of broiler chickens to varying light intensities had a minor effect on physiological blood variables, whereas high ambient temperature markedly affected various blood variables without inducing stress in broilers.

  16. Soot measurements for diesel and biodiesel spray combustion under high temperature highly diluted ambient conditions

    KAUST Repository

    Zhang, Ji

    2014-11-01

    This paper presents the soot temperature and KL factor for biodiesel, namely fatty acid methyl ester (FAME) and diesel fuel combustion in a constant volume chamber using a two-color technique. The KL factor is a parameter for soot concentration, where K is an absorption coefficient and proportional to the number density of soot particles, L is the geometric thickness of the flame along the optical detection axis, and KL factor is proportional to soot volume fraction. The main objective is to explore a combustion regime called high-temperature and highly-diluted combustion (HTHDC) and compare it with the conventional and low-temperature combustion (LTC) modes. The three different combustion regimes are implemented under different ambient temperatures (800 K, 1000 K, and 1400 K) and ambient oxygen concentrations (10%, 15%, and 21%). Results are presented in terms of soot temperature and KL factor images, time-resolved pixel-averaged soot temperature, KL factor, and spatially integrated KL factor over the soot area. The time-averaged results for these three regimes are compared for both diesel and biodiesel fuels. Results show complex combined effects of the ambient temperature and oxygen concentration, and that two-color temperature for the HTHDC mode at the 10% oxygen level can actually be lower than the conventional mode. Increasing ambient oxygen and temperature increases soot temperature. Diesel fuel results in higher soot temperature than biodiesel for all three regimes. Results also show that diesel and biodiesel fuels have very different burning and sooting behavior under the three different combustion regimes. For diesel fuel, the HTHDC regime offers better results in terms of lower soot than the conventional and LTC regimes, and the 10% O2, 1400 K ambient condition shows the lowest soot concentration while maintaining a moderate two-color temperature. For biodiesel, the 15% O2, 800 K ambient condition shows some advantages in terms of reducing soot

  17. Effects of Elevated Ambient Temperature on Reproductive Outcomes and Offspring Growth Depend on Exposure Time

    Directory of Open Access Journals (Sweden)

    Huda Yahia Hamid

    2012-01-01

    Full Text Available Reproductive performance has been shown to be greatly affected by changes in environmental factors, such as temperature. However, it is also crucial to identify the particular stage of pregnancy that is most adversely affected by elevated ambient temperature. The aims of this study were to determine the effect on reproductive outcomes of exposure to elevated ambient temperature during different stages of pregnancy and to determine the effect of prenatal heat stress on offspring growth. Sixty pregnant rats were used in this study. The rats were divided equally into four groups as group 1 (control, group 2 (exposed to elevated temperature following implantation, group 3 (exposed to elevated temperature during pre- and periimplantation, and group 4 (exposed to elevated temperature during pre- and periimplantation and following implantation. Groups 3 and 4 had prolonged gestation periods, reduced litter sizes, and male-biased sex ratios. Moreover, the growth patterns of group 3 and 4 pups were adversely affected by prenatal exposure to elevated temperature. The differences between group 1 and group 3 and between group 1 and group 4 were highly significant. However, no significant differences were observed between groups 1 and 2 in the gestation length, sex ratios, and growth patterns. Thus, it can be concluded that exposure to elevated ambient temperature during pre- and periimplantation has stronger adverse effects on reproductive outcomes and offspring growth than postimplantation exposure.

  18. Evaporative cooling for lactating sows under high ambient temperature

    Directory of Open Access Journals (Sweden)

    Charles Kiefer

    2012-05-01

    Full Text Available Two experiments were conducted to evaluate the evaporative cooling of the air at farrowing on the performance of lactating sows under high environmental temperature conditions in the Central West region of Brazil. One hundred and forty-four lactating sows - 46 of first and second farrowing (experiment I and 98 from the third to eighth farrowing (experiment II - were used. Sows were distributed in experimental design of randomized blocks consisting of two rooms (with air cooling and control, with the sow as the experimental unit. The average duration of lactation was 21 days. Sows were fed ad libitum with the same lactation diet. In experiment I, the air cooling increased the daily feed intake, reduced the total and percent weight loss, increased the weight of the piglets and litters at weaning and improved the daily milk production of sows. However, the air cooling did not affect the weight of the sows or the number of piglets at weaning. In experiment II the air cooling increased the daily feed intake of the sows, reduced the total and percent weight loss, increased the weight and the weight gain of the piglets and litters and improved the daily milk production of the sows. Air cooling enables the increase of the daily feed intake and, therefore, of nutrients by the sows, with consequent reduction of mobilization of body reserves and the increase in the milk production and in the weight of piglets and litters at weaning, regardless the farrowing order of the sow.

  19. SRF Performance of CEBAF After Thermal Cycle to Ambient Temperature

    CERN Document Server

    Rimmer, Robert; Preble, Joseph P; Reece, Charles E

    2005-01-01

    In September 2003, in the wake of Hurricane Isabel, JLab was without power for four days after a tree fell on the main power lines feeding the site. This was long enough to lose insulating vacuum in the cryomodules and cryogenic systems resulting in the whole accelerator warming up and the total loss of the liquid helium inventory. This thermal cycle stressed many of the cryomodule components causing several cavities to become inoperable due to helium to vacuum leaks. At the same time the thermal cycle released years of adsorbed gas from the cold surfaces. Over the next days and weeks this gas was pumped away, the insulating vacuum was restored and the machine was cooled back down and re-commissioned. In a testament to the robustness of SRF technology, only a small loss in energy capability was apparent, although individual cavities had quite different field-emission characteristics compared to before the event. In Summer 2004 a section of the machine was again cycled to room temperature during the long maint...

  20. Enhanced neuroendocrine response to insulin tolerance test performed under increased ambient temperature.

    Science.gov (United States)

    Jezová, D; Kvetnanský, R; Nazar, K; Vigas, M

    1998-01-01

    The hypothesis that an increase in ambient temperature modulates neuroendocrine response in clinically used provocative pituitary function tests was verified. Healthy male volunteers were subjected to insulin tolerance tests in two randomized trials. In the first trial hypoglycemia was induced by a bolus injection of insulin (0.1 U per kg of BW, i.v.) at room temperature. In the second trial, the subjects were exposed to increased ambient temperature for 45 min before insulin injection and for 45 min thereafter. The environmental temperature was selected to increase body temperature less than 1C. Under conditions of increased temperature basal hormone levels as measured in antecubital venous blood samples failed to be modified and the hypoglycemia was less severe. Nevertheless, the responses of most (beta-endorphin, ACTH, prolactin, catecholamines), but not all (growth hormone, cortisol), hormones to hypoglycemia were exaggerated. The remarkable increase in ACTH and beta-endorphin release was not accompanied by concomitant increase of plasma cortisol response. The sympathetic-adrenomedullary system was significantly activated, which was manifested particularly by enhanced norepinephrine release. Growth hormone response to hypoglycemia was not modified, while that of prolactin was enhanced. Thus during evaluation of neuroendocrine function under clinical conditions, changes in ambient and body temperature should not be underestimated.

  1. Prediction of vertical distribution and ambient development temperature of Baltic cod, Gadus morhua L., eggs

    DEFF Research Database (Denmark)

    Wieland, Kai; Jarre, Astrid

    1997-01-01

    situation was observed. Mean ambient temperatures, calculated from the predicted vertical distributions of the eggs and used for the computation of egg developmental times, were overestimated by 0.05 degrees C on average. This corresponds to an error in prediction of egg developmental time of less than 1%...

  2. Gold-Catalyzed Aerobic Oxidation of 5-Hydroxymethylfurfural in Water at Ambient Temperature

    DEFF Research Database (Denmark)

    Gorbanev, Yury; Kegnæs, Søren; Woodley, John

    2009-01-01

    The aerobic oxidation of 5-hydroxymethylfurfural, a versatile biomass-derived chemical, is examined in water with a titania-supported gold-nanoparticle catalyst at ambient temperature (30 degrees C). The selectivity of the reaction towords 2,5-furandicarboxylic acid and the intermediate oxidation...

  3. Why cross-national differences in role overload? Don't overlook ambient temperature!

    NARCIS (Netherlands)

    Van de Vliert, E.; Van Yperen, N.W.

    1996-01-01

    The finding that, across nations, power distance (expected and accepted unequal interpersonal influence) Is positively related to role overload (Peterson et al., 1995) might he an artifact of the relation between role overload and ambient temperature or other third factors. We related data on power

  4. Water-free Alkaline Polymer-inorganic Acid Complexes with High Conductivity at Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    O.V.Chervakov; M.V.Andriianova; V.V.Riabenko; A.V.Markevich; E.M.Shembel; D.Meshri

    2007-01-01

    1 Results Recently increased interest is shown to proton conducting materials based on the alkaline polymer-inorganic acid complexes that is caused by a possibility of their application as the high-temperature electrolyte systems for various electrochemical devices (fuel cells,sensors,lithium power sources etc.).Complexes of inorganic acids with the alkaline polymers (polybenzimidazoles[1],polyvinylpyridines[2]) are characterized by high ionic conductivity at ambient temperatures (up to 10-2 Ω-1·cm-1) a...

  5. The monitoring and fatigue behavior of CFCCs at ambient temperature and 1000{degrees}C

    Energy Technology Data Exchange (ETDEWEB)

    Miriyala, N.; Liaw, P.K.; McHargue, C.J. [Univ. of Tennessee, Knoxville, TN (United States)] [and others

    1997-04-01

    Metallographically polished flexure bars of Nicalon/SiC and Nicalon/alumina composites were subjected to monotonic and cycle-fatigue loadings, with loading either parallel or normal to the fabric plies. The fabric orientation did not significantly affect the mechanical behavior of the Nicalon/SiC composite at ambient temperature. However, the mechanical behavior of the Nicalon/alumina composite was significantly affected by the fabric orientation at ambient temperature in air and at 1000{degrees}C in argon atmosphere. In addition, there was a significant degradation in the fatigue performance of the alumina matrix composite at the elevated temperature, owing to creep in the material and degradation in the fiber strength.

  6. Effect of ambient temperatures on disinfection efficiency of various sludge treatment technologies.

    Science.gov (United States)

    Bauerfeld, Katrin

    2014-01-01

    Sewage sludge produced during municipal wastewater treatment has to be treated efficiently in order to reduce impacts on the environment and on public health. In Germany and many countries, large quantities of sludge are reused in agriculture in order to recycle nutrients and organic material. In order to quantify the effect of different ambient temperatures on conventional and advanced sludge treatment technologies as well as on disinfection efficiency, a comprehensive research study was performed at Braunschweig Institute of Technology. The detailed results show that ambient temperature has a strong effect on biological liquid sludge stabilization and on natural dewatering and drying technologies, although microbiological quality of treated sludge, indicated by Escherichia coli concentration, does not meet the requirements for unrestricted reuse in agriculture. Composting and lime treatment of sludge are most efficient on reducing E. coli, as high temperatures and high pH values arise in the material respectively.

  7. Effects of Imidapril on Venous Blood Gas Values in Broiler Chickens Exposed to Low Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    Xueqin HAO; Meng LI; Shouyan ZHANG; Yongshu WANG; Tongwen SUN

    2013-01-01

    [Objective] This study was designed to evaluate the effects of imidapril on blood gas parameters in broiler chickens.[Method] Twenty-four chickens were randomly divided into three groups (n=8),control group,low temperature group and imidapril group.Chickens in low temperature group and imidapril group were exposed to low ambient temperature (12-18 ℃) from age at 14 d to 45 d,whereas the control group was exposed to 24-30 ℃; chickens in imidapril group were gavaged with imidapril (3 mg/kg) once daily for 30 d.At age of 45 d,blood was taken from wing vein and blood gas parameters were evaluated by blood gas analyzer in Luoyang Central Hospital Affiliated to Zhengzhou University.[Result] Imidapril significantly increased hematocrit (HCT) and total hemoglobin content (THBC) and blood Na concentration in broiler chickens exposed to low ambient temperature.No significant differences were observed in pH,Pco2,Po2,K+,Ca2+,HCO3-,HCO3std,Tco2,BE and SO2c.[Conclusion] Imidapril increases hematocrit,total hemoglobin content and blood Na+concentration in chickens exposed to low ambient temperature.

  8. The importance of ambient temperature to growth and the induction of flowering.

    Directory of Open Access Journals (Sweden)

    C. Robertson Mcclung

    2016-08-01

    Full Text Available Plant development is exquisitely sensitive to the environment. Light quantity, quality, and duration (photoperiod have profound effects on vegetative morphology and flowering time. Recent studies have demonstrated that ambient temperature is a similarly potent stimulus influencing morphology and flowering. In Arabidopsis, ambient temperatures that are high, but not so high as to induce a heat stress response, confer morphological changes that resemble the shade avoidance syndrome. Similarly, these high but not stressful temperatures can accelerate flowering under short day conditions as effectively as exposure to long days. Photoperiodic flowering entails a series of external coincidences, in which environmental cycles of light and dark must coincide with an internal cycle in gene expression established by the endogenous circadian clock. It is evident that a similar model of external coincidence applies to the effects of elevated ambient temperature on both vegetative morphology and the vegetative to reproductive transition. Further study is imperative, because global warming is predicted to have major effects on the performance and distribution of wild species and strong adverse effects on crop yields. It is critical to understand temperature perception and response at a mechanistic level and to integrate this knowledge with our understanding of other environmental responses, including biotic and abiotic stresses, in order to improve crop production sufficiently to sustainably feed an expanding world population.

  9. Design of Cold-Formed Steel Screw Connections with Gypsum Sheathing at Ambient and Elevated Temperatures

    Directory of Open Access Journals (Sweden)

    Wei Chen

    2016-09-01

    Full Text Available Load-bearing cold-formed steel (CFS walls sheathed with double layers of gypsum plasterboard on both sides have demonstrated good fire resistance and attracted increasing interest for use in mid-rise CFS structures. As the main connection method, screw connections between CFS and gypsum sheathing play an important role in both the structural design and fire resistance of this wall system. However, studies on the mechanical behavior of screw connections with double-layer gypsum sheathing are still limited. In this study, 200 monotonic tests of screw connections with single- or double-layer gypsum sheathing at both ambient and elevated temperatures were conducted. The failure of screw connections with double-layer gypsum sheathing in shear was different from that of single-layer gypsum sheathing connections at ambient temperature, and it could be described as the breaking of the loaded sheathing edge combined with significant screw tilting and the loaded sheathing edge flexing fracture. However, the screw tilting and flexing fracture of the loaded sheathing edge gradually disappear at elevated temperatures. In addition, the influence of the loaded edge distance, double-layer sheathing and elevated temperatures is discussed in detail with clear conclusions. A unified design formula for the shear strength of screw connections with gypsum sheathing is proposed for ambient and elevated temperatures with adequate accuracy. A simplified load–displacement model with the post-peak branch is developed to evaluate the load–displacement response of screw connections with gypsum sheathing at ambient and elevated temperatures.

  10. Effect of Ambient Temperature on Body Temperature and Rest Metabolic Rate in Apodemus chevrieri During Postnatal Development

    Directory of Open Access Journals (Sweden)

    Zhu Wan-long

    2014-05-01

    Full Text Available In order to investigate the ability of constant temperature and thermoregulation in Apodemus chevrieri, body temperature and rest metabolic rate (RMR were measured during postnatal development (1~42 day when the A. chevrieri exposed different ambient temperature. The result showed that: body temperature and RMR of pups in A. chevrieri increased according to the increase of ambient temperature during 1 day to 7 day, showed character of poikilotherms; body temperature of pups were lower in low temperature(5oC and 10oC, relatively and RMR significant increased when day age is 14 day, it indicated that the pups showed a certain degree of thermoregulation in this phase. Its thermoregulation ability developed quickly during 7 day to 14 day. RMR of pups was extreme significantly higher in low temperature than that in other temperature when day age was 21 day, it showed that the pups had some thermoregulation to low temperature stimulation. The RMR of pups was showed increasing trend in high temperature(35oC when 28 day; when day age was 35 day and 42 day, the thermal neutral zone were 22.5 to 30oC and approaching its adult level. All of these results indicated that pups of A. chevrieri in the different growing period had different thermogenesis and energy allocation to maintain stable to body temperature, thermogenesis was weaker in the early phase of postnatal development, most of energy is used to its growth. After pups were weaned, the ability of constant temperature and thermoregulation developed quickly to adjust variations of environment during postnatal development.

  11. Modeling Temperature Development of Li-Ion Battery Packs in Hybrid Refuse Truck Operating at Different Ambient Conditions

    DEFF Research Database (Denmark)

    Coman, Paul Tiberiu; Veje, Christian

    2014-01-01

    This paper presents a dynamic model for simulating the heat dissipation and the impact of Phase Change Materials (PCMs) on the peak temperature in Lithium-ion batteries during discharging operation of a hybrid truck under different ambient temperatures.......This paper presents a dynamic model for simulating the heat dissipation and the impact of Phase Change Materials (PCMs) on the peak temperature in Lithium-ion batteries during discharging operation of a hybrid truck under different ambient temperatures....

  12. Fatigue monitoring and analysis of orthotropic steel deck considering traffic volume and ambient temperature

    Institute of Scientific and Technical Information of China (English)

    SONG; YongSheng; DING; YouLiang

    2013-01-01

    Fatigue has gradually become a serious issue for orthotropic steel deck used for long-span bridges. Two fatigue effects, namely number of stress cycles and equivalent stress amplitude, were introduced as investigated parameters in this paper. Investigation was focused on their relationships with traffic volume and ambient temperature by using 7-months fatigue monitoring data of an actual bridge. A fatigue analytical model considering temperature-induced changes in material property of asphalt pavement was established for verifying these relationships. The analysis results revealed that the number of stress cycles and equivalent stress amplitude showed a linear correlation with the traffic volume and ambient temperature, respectively, and that the rib-to-deck welded joint was much more sensitive to the traffic volume and ambient temperature than the rib-to-rib welded joint. The applicability of the code-recommended model for fatigue vehicle loading was also discussed, which revealed that the deterministic vehicle loading model requires improvement to account for significant randomness of the actual traffic conditions.

  13. Live pups from evaporatively dried mouse sperm stored at ambient temperature for up to 2 years.

    Directory of Open Access Journals (Sweden)

    Jie Liu

    Full Text Available The purpose of this study is to develop a mouse sperm preservation method based on evaporative drying. Mouse sperm were evaporatively dried and stored at 4°C and ambient temperature for 3 months to 2 years. Upon rehydration, a single sperm was injected into a mature oocyte to develop into a blastocyst after culture or a live birth after embryo transfer to a recipient female. For the samples stored at 4°C for 3, 6, 12, 18, and 24 months, the blastocyst formation rate was 61.5%, 49.1%, 31.5%, 32.2%, and 41.4%, respectively. The blastocyst rate for those stored at ambient temperature (∼22°C for 3, 6, 12, and 18 months was 57.8%, 36.2%, 33.6%, and 34.4%, respectively. Fifteen, eight and three live pups were produced from sperm stored at room temperature for 12, 18, and 24 months, respectively. This is the first report of live offspring produced from dried mouse sperm stored at ambient temperature for up to 2 years. Based on these results, we suggest that evaporative drying is a potentially useful method for the routine preservation of mouse sperm.

  14. Analyzing the impact of ambient temperature indicators on transformer life in different regions of Chinese mainland.

    Science.gov (United States)

    Bai, Cui-fen; Gao, Wen-Sheng; Liu, Tong

    2013-01-01

    Regression analysis is applied to quantitatively analyze the impact of different ambient temperature characteristics on the transformer life at different locations of Chinese mainland. 200 typical locations in Chinese mainland are selected for the study. They are specially divided into six regions so that the subsequent analysis can be done in a regional context. For each region, the local historical ambient temperature and load data are provided as inputs variables of the life consumption model in IEEE Std. C57.91-1995 to estimate the transformer life at every location. Five ambient temperature indicators related to the transformer life are involved into the partial least squares regression to describe their impact on the transformer life. According to a contribution measurement criterion of partial least squares regression, three indicators are conclusively found to be the most important factors influencing the transformer life, and an explicit expression is provided to describe the relationship between the indicators and the transformer life for every region. The analysis result is applicable to the area where the temperature characteristics are similar to Chinese mainland, and the expressions obtained can be applied to the other locations that are not included in this paper if these three indicators are known.

  15. Ambient temperature nanoelectrospray ion mobility detector for high performance liquid chromatography in determining amines.

    Science.gov (United States)

    Chen, Chuang; Hou, Keyong; Wang, Weiguo; Li, Jinghua; Li, Haiyang

    2014-09-01

    A nanoelectrospray ionization ion mobility spectrometer (nanoESI-IMS) working at ambient pressure and ambient temperature was developed as a detector of high performance liquid chromatography (HPLC) to achieve sensitive detection of amines with no derivatization and meanwhile provide another dimension of separation. The easier desolvation property of the charged droplets formed in nanoESI source enabled complete desolvation of the product ions of sixteen amines and drugs using the nanoESI-IMS at ambient temperature. Working at ambient temperature was good for suppressing the dissociation of thermal volatile ions, such as only the proton adducted molecular ions were observed for morphine in the nanoESI-IMS. Besides, the resolving power of the nanoESI-IMS also showed an increasing tendency as lowering the working temperature, an increment of 19 percent and 10 percent was observed for diethylamine and triethylamine as the temperature dropped from 92°C to 32°C. The resolving power of the nanoESI-IMS at 32°C for the 16 tested compounds was amid 33-44. With the nanoESI-IMS coupled to HPLC, a six-compound mixture including isomers was successfully separated and detected without any derivatization. And linear response ranges of 1 to 20, 0.5 to 20, and 0.8 to 20μgml(-1) and limits of detection of 0.25, 0.15, and 0.17μgml(-1) for triethylamine, diethylamine, and butylamine, respectively, were obtained with the hyphenated system. These results showed the excellent performance of the two-dimensional separation and detection method in direct qualitative and quantitative analyses of amines.

  16. Ambient Temperature Hybrid Polymer Electrolyte Based on Pvk + Pvdf-Hfp for Lithium Batteries

    Science.gov (United States)

    Michael, M. S.; Prabaharan, S. R. S.

    2002-12-01

    Proposed herein is a new ambient temperature Li+ conducting PVDF-HFP-co-polymer based hybrid polymer electrolyte with polyvinyl carbozole (PVK) as additive. The addition of the latter provides high ambient temperature electrolytic conductivity (σi) 0.7 × 10-3S/cm with an ionic transference number of 0.6, besides providing the thermoplastic flexibility to the whole matrix. The membrane is found to exhibit a wide electrochemical potential window, >4.5V against Li/Li+. When prepared properly, the membrane is dry and free standing, yet totally suitable for lithium polymer rechargeable batteries. This paper presents the preparation, microstructure and electrochemical characteristics of this new hybrid polymeric membrane. Finally, the dry polymeric electrolyte membrane has been employed in a lithium polymer cell against LT-LiCo0.8Ni0.2O2 as positive electrode and its interfacial behavior and electrochemical cycling results are presented.

  17. Evaluation of Aluminum Alloy 2050-T84 Microstructure and Mechanical Properties at Ambient and Cryogenic Temperatures

    Science.gov (United States)

    Hafley, Robert A.; Domack, Marcia S.; Hales, Stephen J.; Shenoy, Ravi N.

    2011-01-01

    Aluminum alloy 2050 is being considered for the fabrication of cryogenic propellant tanks to reduce the mass of future heavy-lift launch vehicles. The alloy is available in section thicknesses greater than that of the incumbent aluminum alloy, 2195, which will enable designs with greater structural efficiency. While ambient temperature design allowable properties are available for alloy 2050, cryogenic properties are not available. To determine its suitability for use in cryogenic propellant tanks, tensile, compression and fracture tests were conducted on 4 inch thick 2050-T84 plate at ambient temperature and at -320degF. Various metallurgical analyses were also performed in order to provide an understanding of the compositional homogeneity and microstructure of 2050.

  18. Test of oxidation behavior of sulfide ores at ambient temperature for fire control

    Institute of Scientific and Technical Information of China (English)

    WU Chao; LI Zi-jun; LI Ming; WU Guo-min

    2007-01-01

    The coincidence of relevant factors, e.g. oxygen absorption quantity, weight increment, water soluble iron ions and sulfate ion of sulfide ore samples in the oxidation process, was tested through experiment. Based on a large number of tests for a group sample of sulfide ores from a mine, some important conclusions were obtained. The results obtained by the investigation indicate that there is no general interpretation relative to the oxygen absorption and the formation products of sulfate ion and water soluble iron ions during the oxidation process of sulfide ores at ambient temperature. However, the weight increment of the sulfide ore samples in the oxidation process at ambient temperature has a linear relationship with the quantity of oxygen absorption.

  19. Psychophysics of a nociceptive test in the mouse: ambient temperature as a key factor for variation.

    Directory of Open Access Journals (Sweden)

    Ivanne Pincedé

    Full Text Available BACKGROUND: The mouse is increasingly used in biomedical research, notably in behavioral neurosciences for the development of tests or models of pain. Our goal was to provide the scientific community with an outstanding tool that allows the determination of psychophysical descriptors of a nociceptive reaction, which are inaccessible with conventional methods: namely the true threshold, true latency, conduction velocity of the peripheral fibers that trigger the response and latency of the central decision-making process. METHODOLOGY/PRINCIPAL FINDINGS: Basically, the procedures involved heating of the tail with a CO(2 laser, recording of tail temperature with an infrared camera and stopping the heating when the animal reacted. The method is based mainly on the measurement of three observable variables, namely the initial temperature, the heating rate and the temperature reached at the actual moment of the reaction following random variations in noxious radiant heat. The initial temperature of the tail, which itself depends on the ambient temperature, very markedly influenced the behavioral threshold, the behavioral latency and the conduction velocity of the peripheral fibers but not the latency of the central decision-making. CONCLUSIONS/SIGNIFICANCE: We have validated a psychophysical approach to nociceptive reactions for the mouse, which has already been described for rats and Humans. It enables the determination of four variables, which contribute to the overall latency of the response. The usefulness of such an approach was demonstrated by providing new fundamental findings regarding the influence of ambient temperature on nociceptive processes. We conclude by challenging the validity of using as "pain index" the reaction time of a behavioral response to an increasing heat stimulus and emphasize the need for a very careful control of the ambient temperature, as a prevailing environmental source of variation, during any behavioral testing of

  20. Moisture Stable Ambient Temperature Ionic Liquids: Solvents for the New Millennium. 1. The Heck Reaction

    Directory of Open Access Journals (Sweden)

    Andrea Dallas

    2000-06-01

    Full Text Available In this paper we report examples of the Heck reaction in the new moisture stable ambient temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6. We have found that the yield of product is comparable with Heck reactions carried out in DMF, the conventional solvent for this reaction, and that the ionic liquid/catalyst mixture can be recycled several times.

  1. Comprehensive particle characterization of modern gasoline and diesel passenger cars at low ambient temperatures

    Science.gov (United States)

    Mathis, Urs; Mohr, Martin; Forss, Anna-Maria

    Particle measurements were performed in the exhaust of five light-duty vehicles (Euro-3) at +23, -7, and -20 °C ambient temperatures. The characterization included measurements of particle number, active surface area, number size distribution, and mass size distribution. We investigated two port-injection spark-ignition (PISI) vehicles, a direct-injection spark-ignition (DISI) vehicle, a compressed ignition (CI) vehicle with diesel particle filter (DPF), and a CI vehicle without DPF. To minimize sampling effects, particles were directly sampled from the tailpipe with a novel porous tube diluter at controlled sampling parameters. The diluted exhaust was split into two branches to measure either all or only non-volatile particles. Effect of ambient temperature was investigated on particle emission for cold and warmed-up engine. For the gasoline vehicles and the CI vehicle with DPF, the main portion of particle emission was found in the first minutes of the driving cycle at cold engine start. The particle emission of the CI vehicle without DPF was hardly affected by cold engine start. For the PISI vehicles, particle number emissions were superproportionally increased in the diameter size range from 0.1 to 0.3 μm during cold start at low ambient temperature. Based on the particle mass size distribution, the DPF removed smaller particles ( dp0.5μm). No significant effect of ambient temperature was observed when the engine was warmed up. Peak emission of volatile nanoparticles only took place at specific conditions and was poorly repeatable. Nucleation of particles was predominately observed during or after strong acceleration at high speed and during regeneration of the DPF.

  2. To flower or not to flower, a temperature-sensitive decision. Characterization of flowering responses at high ambient temperature in Arabidopsis thaliana

    NARCIS (Netherlands)

    Rodenburg, N.

    2015-01-01

    To maximize fitness, plants use environmental cues to optimize growth processes. One of the processes under strong environmental regulation is flowering. Multiple environmental factors influence flowering, including temperature. Both a continuously increased ambient temperature as well as temporary

  3. To flower or not to flower, a temperature-sensitive decision : Characterization of flowering responses at high ambient temperature in Arabidopsis thaliana

    NARCIS (Netherlands)

    Rodenburg, Nicole

    2015-01-01

    To maximize fitness, plants use environmental cues to optimize growth processes. One of the processes under strong environmental regulation is flowering. Multiple environmental factors influence flowering, including temperature. Both a continuously increased ambient temperature as well as temporary

  4. Correlations among factors of sulfide ores in oxidation process at ambient temperature

    Institute of Scientific and Technical Information of China (English)

    吴超; 李孜军; 周勃

    2004-01-01

    Spontaneous combustion is one of the serious problems in the mining of sulfide ore deposits. The relevant factors, e. G. Oxygen absorption quantity, mass increase, contents of water soluble iron ions and sulfate ion of sulfide ore samples in the oxidation process were investigated both in theory and experiment. The results from the investigation show that there is no general interpretation relation among the oxygen absorption quantity, the contents of sulfate ion and water soluble iron ions during the oxidation process of sulfide ores at ambient temperature.However, there is a linear relationship between the mass increase of the sulfide ore samples in the oxidation process at ambient temperature and the quantity of oxygen absorption. Therefore, the simple and cheap mass scaling method is suitable for predicting the oxygen absorption performance of sulfide ores at ambient temperature in place of the expensive and complicated chemical method used hitherto. Furthermore, combined with other items of breeding-fire test, the mass increase potential can also be used to predict the spontaneous combustion tendency of sulfide ores.

  5. Ambient maximum temperature as a function of Salmonella food poisoning cases in the Republic of Macedonia

    Directory of Open Access Journals (Sweden)

    Vladimir Kendrovski

    2011-01-01

    Full Text Available Background: Higher temperatures have been associated with higher salmonellosis notifications worldwide. Aims : The objective of this paper is to assess the seasonal pattern of Salmonella cases among humans. Material and Methods: The relationship between ambient maximum temperature and reports of confirmed cases of Salmonella in the Republic of Macedonia and Skopje during the summer months (i.e. June, July, August and September beginning in 1998 through 2008 was investigated. The monthly number of reported Salmonella cases and ambient maximum temperatures for Skopje were related to the national number of cases and temperatures recorded during the same timeframe using regression statistical analyses. The Poisson regression model was adapted for the analysis of the data. Results: While a decreasing tendency was registered at the national level, the analysis for Skopje showed an increasing tendency for registration of new salmonella cases. Reported incidents of salmonellosis, were positively associated (P<0.05 with temperature during the summer months. By increasing of the maximum monthly mean temperature of 1° C in Skopje, the salmonellosis incidence increased by 5.2% per month. Conclusions: The incidence of Salmonella cases in the Macedonian population varies seasonally: the highest values of the Seasonal Index for Salmonella cases were registered in the summer months, i.e. June, July, August and September.

  6. Ambient temperature influences tolerance to plant secondary compounds in a mammalian herbivore.

    Science.gov (United States)

    Kurnath, P; Merz, N D; Dearing, M D

    2016-01-13

    Growing evidence suggests that plant secondary compounds (PSCs) ingested by mammals become more toxic at elevated ambient temperatures, a phenomenon known as temperature-dependent toxicity. We investigated temperature-dependent toxicity in the desert woodrat (Neotoma lepida), a herbivorous rodent that naturally encounters PSCs in creosote bush (Larrea tridentata), which is a major component of its diet. First, we determined the maximum dose of creosote resin ingested by woodrats at warm (28-29°C) or cool (21-22°C) temperatures. Second, we controlled the daily dose of creosote resin ingested at warm, cool and room (25°C) temperatures, and measured persistence in feeding trials. At the warm temperature, woodrats ingested significantly less creosote resin; their maximum dose was two-thirds that of animals at the cool temperature. Moreover, woodrats at warm and room temperatures could not persist on the same dose of creosote resin as woodrats at the cool temperature. Our findings demonstrate that warmer temperatures reduce PSC intake and tolerance in herbivorous rodents, highlighting the potentially adverse consequences of temperature-dependent toxicity. These results will advance the field of herbivore ecology and may hone predictions of mammalian responses to climate change.

  7. Development of CABAL glasses for use in lithium ambient-temperature batteries

    Science.gov (United States)

    Watkins, Randall D.

    1987-06-01

    Calcium-boro-aluminate (CABAL) glasses have been developed for use as electrically insulating sealing glasses in lithium ambient-temperature batteries. CABAL glasses have superior corrosion resistance in lithium/electrolyte environments relative to TA-23, and battery lifetimes are now being projected beyond 25 y. In addition, these glasses require much lower melting and sealing temperatures than TA-23. This report outlines the evolution of the CABAL glass technology at Sandia, from original composition selection to identification of the optimum CABAL-12 composition. Seal processing including commercial glass fabrication, mechanical testing, and microstructural evaluation are discussed, and the results of our initial technology transfer efforts are summarized.

  8. Effect of ambient temperature on endurance performance while wearing cross-country skiing clothing.

    Science.gov (United States)

    Sandsund, Mariann; Saursaunet, Vegard; Wiggen, Øystein; Renberg, Julie; Færevik, Hilde; van Beekvelt, Mireille C P

    2012-12-01

    This study assessed the effects of exposure to cold (-14 and -9 °C), cool (-4 and 1 °C) and moderate warm (10 and 20 °C) environments on aerobic endurance performance-related variables: maximal oxygen consumption (VO(2max)), running time to exhaustion (TTE), running economy and running speed at lactate threshold (LT). Nine male endurance athletes wearing cross-country ski racing suit performed a standard running test at six ambient temperatures in a climatic chamber with a wind speed of 5 m s(-1). The exercise protocol consisted of a 10-min warm-up period followed by four submaximal periods of 5 min at increasing intensities between 67 and 91 % of VO(2max) and finally a maximal test to exhaustion. During the time course mean skin temperature decreased significantly with reduced ambient temperatures whereas T (re) increased during all conditions. T (re) was lower at -14 °C than at -9 and 20 °C. Running economy was significantly reduced in warm compared to cool environments and was also reduced at 20 °C compared to -9 °C. Running speed at LT was significantly higher at -4 °C than at -9, 10 and 20 °C. TTE was significantly longer at -4 and 1 °C than at -14, 10 and 20 °C. No significant differences in VO(2max) were found between the various ambient conditions. The optimal aerobic endurance performance wearing a cross-country ski racing suit was found to be -4 and 1 °C, while performance was reduced under moderate warm (10 and 20 °C) and cold (-14 and -9 °C) ambient conditions.

  9. Thermal responses and perceptions under distinct ambient temperature and wind conditions.

    Science.gov (United States)

    Shimazaki, Yasuhiro; Yoshida, Atsumasa; Yamamoto, Takanori

    2015-01-01

    Wind conditions are widely recognized to influence the thermal states of humans. In this study, we investigated the relationship between wind conditions and thermal perception and energy balance in humans. The study participants were exposed for 20 min to 3 distinct ambient temperatures, wind speeds, and wind angles. During the exposure, the skin temperatures as a physiological reaction and mental reactions of the human body were measured and the energy balance was calculated based on the human thermal-load method. The results indicate that the human thermal load is an accurate indicator of human thermal states under all wind conditions. Furthermore, wind speed and direction by themselves do not account for the human thermal experience. Because of the thermoregulation that occurs to prevent heat loss and protect the core of the body, a low skin temperature was maintained and regional differences in skin temperature were detected under cool ambient conditions. Thus, the human thermal load, which represents physiological parameters such as skin-temperature change, adequately describes the mixed sensation of the human thermal experience.

  10. On exhaust emissions from petrol-fuelled passenger cars at low ambient temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Laurikko, J. [VTT Energy, Espoo (Finland). Energy Use

    1998-11-01

    The study at hand deals with regulated and unregulated exhaust emissions from petrol-fuelled cars at low ambient temperatures with present-day or near-future exhaust after treatment systems. The subject has been investigated at VTT over a decade and this report compiles data from various sub-studies carried out between the years 1993 - 1997. Each one of them viewed different aspects of the phenomenon, like determining the low-temperature response of today`s new cars employing three-way catalytic converters or assessing the long-term durability and the influence of vehicle mileage upon the low-temperature emissions performance. Within these studies, together more than 120 cars of model years from 1990 to 1997 have been tested. Most of them were normal, in-service vehicles with total mileages differing between only a few thousand kilometres for new cars up to 80,000 km or even more for the in-use vehicles. Both the US FTP75 and the European test cycle have been employed, and the ambient temperatures ranged from the baseline (+22 deg C) down to +- O deg C, -7 deg C and in some cases even to -20 deg C. The studies attested that new cars having today`s advanced emissions control systems produced fairly low levels of emissions when tested in conditions designated in the regulations that are the basis of the current new-vehicle certification. However, this performance was not necessarily attained at ambient temperatures that were below the normative range. Fairly widespread response was recorded, and cars having almost equal emissions output at baseline could produce largely deviating outcomes in low-temperature conditions. On average, CO and HC emissions increased by a factor of five to 10, depending on the ambient temperature and vehicle type. However, emissions of NO{sub x} were largely unaffected. Apart from these regulated emissions, many unregulated species were also determined, either by using traditional sampling and chromatography methods or on-line, employing

  11. Influence of variable heat transfer coefficient of fireworks and crackers on thermal explosion critical ambient temperature and time to ignition

    Directory of Open Access Journals (Sweden)

    Guo Zerong

    2016-01-01

    Full Text Available To study the effect of variable heat transfer coefficient of fireworks and crackers on thermal explosion critical ambient temperature and time to ignition, considering the heat transfer coefficient as the power function of temperature, mathematical thermal explosion steady state and unsteady-state model of finite cylindrical fireworks and crackers with complex shell structures are established based on two-dimensional steady state thermal explosion theory. The influence of variable heat transfer coefficient on thermal explosion critical ambient temperature and time to ignition are analyzed. When heat transfer coefficient is changing with temperature and in the condition of natural convection heat transfer, critical ambient temperature lessen, thermal explosion time to ignition shorten. If ambient temperature is close to critical ambient temperature, the influence of variable heat transfer coefficient on time to ignition become large. For firework with inner barrel in example analysis, the critical ambient temperature of propellant is 463.88 K and the time to ignition is 4054.9s at 466 K, 0.26 K and 450.8s less than without considering the change of heat transfer coefficient respectively. The calculation results show that the influence of variable heat transfer coefficient on thermal explosion time to ignition is greater in this example. Therefore, the effect of variable heat transfer coefficient should be considered into thermal safety evaluation of fireworks to reduce potential safety hazard.

  12. On exergy analysis of industrial plants and significance of ambient temperature

    Energy Technology Data Exchange (ETDEWEB)

    Rian, Berit

    2011-07-01

    The exergy analysis has been a relatively mature theory for more than 30 years. However, it is not that developed in terms of procedures for optimizing systems, which partly explains why it is not that common. Misconceptions and prejudices, even among scientists, are also partly to blame.The main objective of this work was to contribute to the development of an understanding and methodology of the exergy analysis. The thesis was mainly based on three papers, two of which provided very different examples from existing industrial systems in Norway, thus showing the societal perspective in terms of resource utilization and thermodynamics. The last paper and the following investigation were limited to certain aspects of ambient conditions. Two Norwegian operational plants have been studied, one operative for close to 30 years (Kaarstoe steam production and distribution system), while the other has just started its expected 30 years of production (Snoehvit LNG plant). In addition to mapping the current operational status of these plants, the study of the Kaarstoe steam production and distribution system concluded that the potential for increasing the thermodynamic performance by rather cautious actions was significant, whereas the study of the Snoehvit LNG plant showed the considerable profit which the Arctic location provided in terms of reduced fuel consumption. The significance of the ambient temperature led to the study of systems with two ambient bodies (i.e. ambient water and ambient air) of different temperatures, here three different systems were investigated: A regenerative steam injection gas turbine (RSTIG), a simple Linde air liquefaction plant (Air Liq) and an air-source heat pump water heater (HPWH). In particular, the effect of the chosen environment on exergy analysis was negligible for RSTIG, modest for Air Liq and critical for HPWH. It was found that the amount of exergy received from the alternative ambient body, compared to the main exergy flow of

  13. Cyclic deformation behaviour of austenitic steels at ambient and elevated temperatures

    Indian Academy of Sciences (India)

    Th Nebel; D Eifler

    2003-02-01

    The aim of the present investigation is to characterise cyclic deformation behaviour and plasticity-induced martensite formation of metastable austenitic stainless steels at ambient and elevated temperatures, taking into account the influence of the alloying elements titanium and niobium. Titanium and niobium are ferrite-stabilising elements which influence the ferrite crystallisation. Furthermore, They form carbides and/or carbonitrides and thus limit the austenite-stabilising effect of carbon and nitrogen. Several specimen batches of titanium and niobium alloyed austenite and of a pure Cr-Ni-steel for comparison were tested under stress and total strain control at a frequency of 5 Hz and triangular load-time waveforms. Stress-strain-hysteresis and temperature measurements were used at ambient temperature to characterise cyclic deformation behaviour. Plasticity-induced martensite content was detected with non-destructive magnetic measuring techniques. The experiments yield characteristic cyclic deformation curves and corresponding magnetic signals according to the actual fatigue state and the amount of martensite. Fatigue behaviour of X6CrNiTi1810 (AISI 321), X10CrNiCb189 (AISI 348) and X5CrNi1810 (AISI 304) is characterised by cyclic hardening and softening effects which are strongly influenced by specific loading conditions. Martensite formation varies with the composition, loading conditions, temperature and number of cycles.

  14. Shaped Refractory Products--Determination of Modulus of Rupture at Ambient Temperature GB/T 3001-2000

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ 1 Scope This standard specifies a method for the determination of the modulus of rupture of dense and insulating shaped refractory products at ambient temperature, under conditions of a constant rate of increase of stress.

  15. Daily ambient temperature and renal colic incidence in Guangzhou, China: a time-series analysis

    Science.gov (United States)

    Yang, Changyuan; Chen, Xinyu; Chen, Renjie; Cai, Jing; Meng, Xia; Wan, Yue; Kan, Haidong

    2016-08-01

    Few previous studies have examined the association between temperature and renal colic in developing regions, especially in China, the largest developing country in the world. We collected daily emergency ambulance dispatches (EADs) for renal colic from Guangzhou Emergency Center from 1 January 2008 to 31 December 2012. We used a distributed-lag nonlinear model in addition to the over-dispersed generalized additive model to investigate the association between daily ambient temperature and renal colic incidence after controlling for seasonality, humidity, public holidays, and day of the week. We identified 3158 EADs for renal colic during the study period. This exposure-response curve was almost flat when the temperature was low and moderate and elevated when the temperature increased over 21 °C. For heat-related effects, the significant risk occurred on the concurrent day and diminished until lag day 7. The cumulative relative risk of hot temperatures (90th percentile) and extremely hot temperatures (99th percentile) over lag days 0-7 was 1.92 (95 % confidence interval, 1.21, 3.05) and 2.45 (95 % confidence interval, 1.50, 3.99) compared with the reference temperature of 21 °C. This time-series analysis in Guangzhou, China, suggested a nonlinear and lagged association between high outdoor temperatures and daily EADs for renal colic. Our findings might have important public health significance to prevent renal colic.

  16. Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments: R-22 and R-410A Alternatives for Rooftop Air Conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Abdelaziz, Omar [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shrestha, Som S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shen, Bo [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Linkous, Randall Lee [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Goetzler, William [Navigant Consulting Inc., Burlington, MA (United States); Guernsey, Matt [Navigant Consulting Inc., Burlington, MA (United States); Bargach, Youssef [Navigant Consulting Inc., Burlington, MA (United States)

    2016-09-01

    The Oak Ridge National Laboratory (ORNL) High-Ambient-Temperature Evaluation Program for Low-Global Warming Potential (Low-GWP) Refrigerants aims to develop an understanding of the performance of low-GWP alternative refrigerants relative to hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) refrigerants in packaged or Rooftop Unit (RTU) air conditioners under high-ambient-temperature conditions. This final report describes the parties involved, the alternative refrigerants selection process, the test procedures, and the final results.

  17. Comparison of Waste Heat Driven and Electrically Driven Cooling Systems for a High Ambient Temperature, Off-Grid Application

    Science.gov (United States)

    2012-12-10

    pumps, and oil -free screw and lobe type compressors . However, given the capacity of the AS, the low flow rates coupled with the low density made it...D R IV EN C O O LI N G COMPARISON OF WASTE HEAT DRIVEN AND ELECTRICALLY DRIVEN COOLING SYSTEMS FOR A HIGH AMBIENT TEMPERATURE, OFF- GRID...2010 to 10-12-2012 4. TITLE AND SUBTITLE COMPARISON OF WASTE HEAT DRIVEN AND ELECTRICALLY DRIVEN COOLING SYSTEMS FOR A HIGH AMBIENT TEMPERATURE

  18. Daily means ambient temperature prediction using artificial neural network method. A case study of Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Altan Dombayci, Oemer [Department of Technical Programmes, Denizli Vocational College, Pamukkale University, 20070 Denizli (Turkey); Goelcue, Mustafa [Department of Mechanical Education, Technical Education Faculty, Pamukkale University, 20070 Denizli (Turkey)

    2009-04-15

    The objective of this paper is to develop an artificial neural network (ANN) model which can be used to predict daily mean ambient temperatures in Denizli, south-western Turkey. In order to train the model, temperature values, measured by The Turkish State Meteorological Service over three years (2003-2005) were used as training data and the values of 2006 were used as testing data. In order to determine the optimal network architecture, various network architectures were designed; different training algorithms were used; the number of neuron and hidden layer and transfer functions in the hidden layer/output layer were changed. The predictions were performed by taking different number of hidden layer neurons between 3 and 30. The best result was obtained when the number of the neurons is 6. The selected ANN model of a multi-layer consists of 3 inputs, 6 hidden neurons and 1 output. Training of the network was performed by using Levenberg-Marquardt (LM) feed-forward backpropagation algorithms. A computer program was performed under Matlab 6.5 software. For each network, fraction of variance (R{sup 2}) and root-mean squared error (RMSE) values were calculated and compared. The results show that the ANN approach is a reliable model for ambient temperature prediction. (author)

  19. Influence of Physical Activity and Ambient Temperature on Hydration: The European Hydration Research Study (EHRS

    Directory of Open Access Journals (Sweden)

    Ricardo Mora-Rodriguez

    2016-04-01

    Full Text Available This study explored the effects of physical activity (PA and ambient temperature on water turnover and hydration status. Five-hundred seventy three healthy men and women (aged 20–60 years from Spain, Greece and Germany self-reported PA, registered all food and beverage intake, and collected 24-h urine during seven consecutive days. Fasting blood samples were collected at the onset and end of the study. Food moisture was assessed using nutritional software to account for all water intake which was subtracted from daily urine volume to allow calculation of non-renal water loss (i.e., mostly sweating. Hydration status was assessed by urine and blood osmolality. A negative association was seen between ambient temperature and PA (r = −0.277; p < 0.001. Lower PA with high temperatures did not prevent increased non-renal water losses (i.e., sweating and elevated urine and blood osmolality (r = 0.218 to 0.163 all p < 0.001. When summer and winter data were combined PA was negatively associated with urine osmolality (r = −0.153; p = 0.001. Our data suggest that environmental heat acts to reduce voluntary PA but this is not sufficient to prevent moderate dehydration (increased osmolality. On the other hand, increased PA is associated with improved hydration status (i.e., lower urine and blood osmolality.

  20. Cold Ambient Temperature Promotes Nosema spp. Intensity in Honey Bees (Apis mellifera).

    Science.gov (United States)

    Retschnig, Gina; Williams, Geoffrey R; Schneeberger, Annette; Neumann, Peter

    2017-02-09

    Interactions between parasites and environmental factors have been implicated in the loss of managed Western honey bee (=HB, Apis mellifera) colonies. Although laboratory data suggest that cold temperature may limit the spread of Nosema ceranae, an invasive species and now ubiquitous endoparasite of Western HBs, the impact of weather conditions on the distribution of this microsporidian in the field is poorly understood. Here, we conducted a survey for Nosema spp. using 18 Swiss apiaries (four colonies per apiary) over a period of up to 18 months. Samples consisting of 60 workers were collected monthly from each colony to estimate Nosema spp. intensity, i.e., the number of spores in positive samples using microscopy. Ambient apiary temperature was measured daily to estimate the proportion of days enabling HB flight (>10 °C at midday). The results show that Nosema spp. intensities were negatively correlated with the proportion of days enabling HB flight, thereby suggesting a significant and unexpected positive impact of cold ambient temperature on intensities, probably via regulation of defecation opportunities for infected hosts.

  1. Cold Ambient Temperature Promotes Nosema spp. Intensity in Honey Bees (Apis mellifera

    Directory of Open Access Journals (Sweden)

    Gina Retschnig

    2017-02-01

    Full Text Available Interactions between parasites and environmental factors have been implicated in the loss of managed Western honey bee (=HB, Apis mellifera colonies. Although laboratory data suggest that cold temperature may limit the spread of Nosema ceranae, an invasive species and now ubiquitous endoparasite of Western HBs, the impact of weather conditions on the distribution of this microsporidian in the field is poorly understood. Here, we conducted a survey for Nosema spp. using 18 Swiss apiaries (four colonies per apiary over a period of up to 18 months. Samples consisting of 60 workers were collected monthly from each colony to estimate Nosema spp. intensity, i.e., the number of spores in positive samples using microscopy. Ambient apiary temperature was measured daily to estimate the proportion of days enabling HB flight (>10 °C at midday. The results show that Nosema spp. intensities were negatively correlated with the proportion of days enabling HB flight, thereby suggesting a significant and unexpected positive impact of cold ambient temperature on intensities, probably via regulation of defecation opportunities for infected hosts.

  2. Daily variations in the influence of noradrenaline on preferred ambient temperature of the Siberian hamster.

    Science.gov (United States)

    Jefimow, Małgorzata; Wojciechowski, Michał; Tegowska, Eugenia

    2003-04-01

    Daily variations in sensitivity to noradrenaline (NA) and the activation of nonshivering thermogenesis (NST) are important for survival under a potentially wide range of environmental conditions. However, little is known regarding the ability of the Siberian hamster and other species to activate NST in the day and night when they may be subjected to marked variations in environmental temperature. In this study, the effects of acclimation temperature and time of day on the behavioral thermoregulatory response to NA injections in Siberian hamsters (Phodopus sungorus) was investigated. Hamsters were acclimated for 4 weeks to 23 degrees C and a L:D 12:12 h photoperiod. After acclimation, preferred ambient temperatures (PT(a)) in saline- and NA-injected animals were measured continuously in the temperature gradient system. NA (0.6 mg/kg; s.c.) was given every 4 h while PT(a) was monitored. After NA injections there was a rapid drop in PT(a), decreasing to approximately 15 degrees C within 10-20 min after each NA injection. Following 4 weeks of acclimation to 10 degrees C and a L:D 8:16 h photoperiod, the same hamsters were re-tested in the temperature gradient system. Cold acclimation led to an accentuation in the behavioral response with a decrease in PT(a) of approximately 10 degrees C. The maximal decrease in preferred ambient temperatures was recorded during the light phase of the day and during the second part of the night. Lowering of PT(a) after NA allows for rapid dissipation of the heat from NST. Overall, the behavioral response reflects the daily changes in brown adipose tissue sensitivity to NA and thus capacity for NST.

  3. Fabrication of AlN thin films on different substrates at ambient temperature

    CERN Document Server

    Cai, W X; Wu, P H; Yang, S Z; Ji, Z M

    2002-01-01

    Aluminium nitride (AlN) is very useful as a barrier in superconductor-insulator-superconductor (SIS) device or as an insulating layer in many other applications. At ambient temperature, we deposit AlN thin films onto different substrates (such as MgO, LaAlO sub 3 and Si) by using radio-frequency magnetron sputtering and pure Al target. X-ray diffraction (XRD) and PHI-scan patterns show that the films grown on MgO substrates are excellent epitaxial films with (101) orientation of a hexagonal lattice. A possible structure of the interface between the film and the substrate is suggested and discussed.

  4. On-demand Hydrogen Production from Organosilanes at Ambient Temperature Using Heterogeneous Gold Catalysts

    Science.gov (United States)

    Mitsudome, Takato; Urayama, Teppei; Kiyohiro, Taizo; Maeno, Zen; Mizugaki, Tomoo; Jitsukawa, Koichiro; Kaneda, Kiyotomi

    2016-11-01

    An environmentally friendly (“green”), H2-generation system was developed that involved hydrolytic oxidation of inexpensive organosilanes as hydrogen storage materials with newly developed heterogeneous gold nanoparticle catalysts. The gold catalyst functioned well at ambient temperature under aerobic conditions, providing efficient production of pure H2. The newly developed size-selective gold nanoparticle catalysts could be separated easily from the reaction mixture containing organosilanes, allowing an on/off-switchable H2-production by the introduction and removal of the catalyst. This is the first report of an on/off-switchable H2-production system employing hydrolytic oxidation of inexpensive organosilanes without requiring additional energy.

  5. Photocatalyst-Free and Blue Light-Induced RAFT Polymerization of Vinyl Acetate at Ambient Temperature.

    Science.gov (United States)

    Ding, Chunlai; Fan, Caiwei; Jiang, Ganquan; Pan, Xiangqiang; Zhang, Zhengbiao; Zhu, Jian; Zhu, Xiulin

    2015-12-01

    Vinyl acetate is polymerized in the living way under the irradiation of blue light-emitting diodes (LEDs) or sunlight without photocatalyst at ambient temperature. 2-(Ethoxycarbonothioyl)sulfanyl propanoate is exclusively added and acts as initiator and chain transfer agent simultaneously in the current system. Poly(vinyl acetate) with well-regulated molecular weight and narrow molecular weight distribution (Đ < 1.30) is synthesized. Near quantitative end group fidelity of polymer is demonstrated by nuclear magnetic resonance (NMR) and matrix-assisteed laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).

  6. Ambient air pollution, temperature and out-of-hospital coronary deaths in Shanghai, China.

    Science.gov (United States)

    Dai, Jinping; Chen, Renjie; Meng, Xia; Yang, Changyuan; Zhao, Zhuohui; Kan, Haidong

    2015-08-01

    Few studies have evaluated the effects of ambient air pollution and temperature in triggering out-of-hospital coronary deaths (OHCDs) in China. We evaluated the associations of air pollution and temperature with daily OHCDs in Shanghai, China from 2006 to 2011. We applied an over-dispersed generalized additive model and a distributed lag nonlinear model to analyze the effects of air pollution and temperature, respectively. A 10 μg/m(3) increase in the present-day PM10, PM2.5, SO2, NO2 and CO were associated with increases in OHCD mortality of 0.49%, 0.68%, 0.88%, 1.60% and 0.08%, respectively. A 1 °C decrease below the minimum-mortality temperature corresponded to a 3.81% increase in OHCD mortality on lags days 0-21, and a 1 °C increase above minimum-mortality temperature corresponded to a 4.61% increase over lag days 0-3. No effects were found for in-hospital coronary deaths. This analysis suggests that air pollution, low temperature and high temperature may increase the risk of OHCDs.

  7. The Influence of Ambient Temperature on Green Roof R-values

    Science.gov (United States)

    Cox, Bryce Kevin

    Green roofs can be an effective and appealing way to increase the energy efficiency of buildings by providing active insulation. As plants in the green roof transpire, there is a reduction in heat flux that is conducted through the green roof. The R-value, or thermal resistance, of a green roof is an effective measurement of thermal performance because it can be easily included in building energy calculations applicable to many different buildings and situations. The purpose of this study was to determine if an increase in ambient temperature would cause an increase in the R-value of green roofs. Test trays containing green roof materials were tested in a low speed wind tunnel equipped to determine the R-value of the trays. Three different plant species were tested in this study, ryegrass (Lolium perenne), sedum (Sedum hispanicum), and vinca (Vinca minor ). For each test in this study the relative humidity was maintained at 45% and the soil was saturated with water. The trays were tested at four different ambient temperatures, ranging from room temperature to 120ºF. The resulting R-values for sedum ranged from 1.37 to 3.28 ft2hºF/BTU, for ryegrass the R-values ranged from 2.15 to 3.62 ft2hºF/BTU, and for vinca the R-values ranged from 3.15 to 5.19 ft2hºF/BTU. The average R-value for all the tests in this study was 3.20 ft2hºF/BTU. The results showed an increase in R-value with increasing temperature. Applying an ANOVA analysis to the data, the relationship between temperature and R-value for all three plant species was found to be statistically significant.

  8. Revealing the association between cerebrovascular accidents and ambient temperature: a meta-analysis

    Science.gov (United States)

    Zorrilla-Vaca, Andrés; Healy, Ryan Jacob; Silva-Medina, Melissa M.

    2016-10-01

    The association between cerebrovascular accidents (CVA) and weather has been described across several studies showing multiple conflicting results. In this paper, we aim to conduct a meta-analysis to further clarify this association, as well as to find the potential sources of heterogeneity. PubMed, EMBASE, and Google Scholar were searched from inception through 2015, for articles analyzing the correlation between the incidence of CVA and temperature. A pooled effect size (ES) was estimated using random effects model and expressed as absolute values. Subgroup analyses by type of CVA were also performed. Heterogeneity and influence of covariates—including geographic latitude of the study site, male percentage, average temperature, and time interval—were assessed by meta-regression analysis. Twenty-six articles underwent full data extraction and scoring. A total of 19,736 subjects with CVA from 12 different countries were included and grouped as ischemic strokes (IS; n = 14,199), intracerebral hemorrhages (ICH; n = 3798), and subarachnoid hemorrhages (SAH; n = 1739). Lower ambient temperature was significantly associated with increase in incidence of overall CVA when using unadjusted (pooled ES = 0.23, P < 0.001) and adjusted data (pooled ES = 0.03, P = 0.003). Subgroup analyses showed that lower temperature has higher impact on the incidence of ICH (pooled ES = 0.34, P < 0.001), than that of IS (pooled ES = 0.22, P < 0.001) and SAH (pooled ES = 0.11, P = 0.012). In meta-regression analysis, the geographic latitude of the study site was the most influencing factor on this association (Z-score = 8.68). Synthesis of the existing data provides evidence supporting that a lower ambient temperature increases the incidence of CVA. Further population-based studies conducted at negative latitudes are needed to clarify the influence of this factor.

  9. Effects of shade on welfare and meat quality of grazing sheep under high ambient temperature.

    Science.gov (United States)

    Liu, H W; Cao, Y; Zhou, D W

    2012-12-01

    This study was conducted to evaluate the effects of providing shade on growth performance, welfare, and meat quality of grazing sheep under high ambient temperature. A total of 120 healthy male Ujumqin wool sheep (a local breed; BW = 18.7 ± 1.27 kg; 14 wk old) were randomly and equally divided into shaded and unshaded treatments with 3 pens per treatment. Sheep were grazed on an unshaded pastureland from 0600 to 1000 h and 1400 to 1800 h. During other times, sheep were confined in shaded or unshaded pens. Body weight was recorded on d 1 and 42 of the experiment. Rectal temperature and respiration rate were recorded on d 7, 14, 21, 28, 35, and 42. At end of the trial, sheep were blood sampled and slaughtered to collect meat samples. Respiration rate was greater (P sheep than shaded sheep on d 14, 21, 28, 35, and 42 of the trial whereas no significant differences were found on d 7. Moreover, no differences were observed in final BW, ADG, or rectal temperature throughout the trial. The pH at 24 h postmortem (pH(24)) and cooking loss were greater (P sheep. On the contrary, lightness (L*), redness (a*) and yellowness (b*) values at 24 h postmortem were lower (P sheep. The sheep in the unshaded group had a greater (P Sheep in the shaded group had lower creatine kinase activity (P sheep in the shaded group had a greater lymphocytes (LYM) count (P meat quality traits and certain stress parameters in grazing sheep reared under high ambient temperature.

  10. Estimating methane emissions from landfills based on rainfall, ambient temperature, and waste composition: The CLEEN model.

    Science.gov (United States)

    Karanjekar, Richa V; Bhatt, Arpita; Altouqui, Said; Jangikhatoonabad, Neda; Durai, Vennila; Sattler, Melanie L; Hossain, M D Sahadat; Chen, Victoria

    2015-12-01

    Accurately estimating landfill methane emissions is important for quantifying a landfill's greenhouse gas emissions and power generation potential. Current models, including LandGEM and IPCC, often greatly simplify treatment of factors like rainfall and ambient temperature, which can substantially impact gas production. The newly developed Capturing Landfill Emissions for Energy Needs (CLEEN) model aims to improve landfill methane generation estimates, but still require inputs that are fairly easy to obtain: waste composition, annual rainfall, and ambient temperature. To develop the model, methane generation was measured from 27 laboratory scale landfill reactors, with varying waste compositions (ranging from 0% to 100%); average rainfall rates of 2, 6, and 12 mm/day; and temperatures of 20, 30, and 37°C, according to a statistical experimental design. Refuse components considered were the major biodegradable wastes, food, paper, yard/wood, and textile, as well as inert inorganic waste. Based on the data collected, a multiple linear regression equation (R(2)=0.75) was developed to predict first-order methane generation rate constant values k as functions of waste composition, annual rainfall, and temperature. Because, laboratory methane generation rates exceed field rates, a second scale-up regression equation for k was developed using actual gas-recovery data from 11 landfills in high-income countries with conventional operation. The Capturing Landfill Emissions for Energy Needs (CLEEN) model was developed by incorporating both regression equations into the first-order decay based model for estimating methane generation rates from landfills. CLEEN model values were compared to actual field data from 6 US landfills, and to estimates from LandGEM and IPCC. For 4 of the 6 cases, CLEEN model estimates were the closest to actual.

  11. Influence of ambient temperature on whole body and segmental bioimpedance spectroscopy measurements

    Science.gov (United States)

    Medrano, G.; Bausch, R.; Ismail, A. H.; Cordes, A.; Pikkemaat, R.; Leonhardt, S.

    2010-04-01

    Bioimpedance spectroscopy (BIS) measurements are easy to implement and could be used for continuous monitoring. However, several factors (e.g. environment temperature) influence the measurements limiting the accuracy of the technology. Changes in skin temperature produced by changes in ambient temperature are related with changes in skin blood flow and skin impedance. It is assumed that skin impedance change is responsible for the error observed in whole body and segmental measurements. Measurements including body parts more distant from the torso seem to be more affected. In the present article skin and segment impedance have been performed on healthy subjects under extreme changes in environment temperature (13-39 °C). A commercial BIS device with a range between 5 kHz and 1 MHz has been used for the measurements. The results indicate that not only skin impedance, but also impedance of deeper tissue (e.g. muscle) may be responsible for the influence of environment temperature on BIS measurements. Segmental (knee-to-knee) BIS measurements show a relative change of only 2 %, while forearm and whole body impedance changed 14 % and 8 % respectively.

  12. Impact of Montmorillonite and Calcite on Release and Adsorption of Cyanobacterial Fatty Acids at Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    Liu Deng; Yang Xiaofen; Wang Hongmei; Li Jihong; Su Nian

    2008-01-01

    Minerals might act as important sorbents of sedimentary organic matter and reduce biodegradation, which favors the formation of hydrocarbon source rocks in the earth's history. Since most organic matter is degraded during the sinking process, at ambient temperature, it is important to investigate the adsorption capacity of different minerals during this process, to assess the organic loss from primary productivity to sedimentary organic matter. In this study, montmorillonite and calcite have been selected to study the impact of different minerals on the release, adsorption, and deposition of cyanobacterial (Synechococcus elonpata) fatty acids (FAs) at ambient temperature. Gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) have been utilized to detect the variation in fatty acids. Primary results suggest that minerals have a different impact on dissolved organic matter. Montmorillonite can specifically enhance the release of fatty acids from cyanobacterial cells by lowering the pH values of the solution. The adsorption of the dissolved organic matter by montmorillonite will also be enhanced under a lower pH value. Conjunction of fatty acids with montmorillonite to form a complex will favor the sinking and preservation of these organics. Selective adsorption is observed among fatty acids with different carbon numbers. In contrast, calcite does not show any impact on the release and adsorption of organic matter even though it is reportedly capable of acting as a catalyst during the transformation of organic matter at high temperature. The primary data bridge a link between primary productivity and sedimentary organic matter, suggesting the relative importance of claystoncs in the formation of hydrocarbon source rocks in the earth's history.

  13. Pressure induced ionic-superionic transition in silver iodide at ambient temperature.

    Science.gov (United States)

    Han, Y H; Wang, H B; Troyan, I A; Gao, C X; Eremets, M I

    2014-01-28

    Silver iodide (AgI-V) is an archetypical ionic compound for studying the formation mechanism of a superionic state. Previous studies have proven that superionic AgI with high ionic conductivity greater than 0.1 Ω(-1)cm(-1) could only be obtained at high temperatures. We show in this paper that high pressure could also induce the superionic state in AgI even at ambient temperature. Using electrochemical impedance spectroscopy, we investigated Ag(+) ions diffusing in rock-salt structured AgI-III and KOH-type AgI-V under high pressures and directly observed the superionic state in AgI-V. The diffusion coefficient of AgI-V is ∼3.4 × 10(-4)-8.6 × 10(-4) cm(2)/s in the investigated pressure range of 12-17 GPa, comparable with those of superionic α-AgI and AgI-III'. By analyzing the half infinite length Warburg diffusion process, two parameters α and β, which closely relate to the disordered state of Ag(+) ions, have been determined and it was suggested that Ag(+) ions in AgI-V become disordered. The ionic conductivity of AgI-V is three orders of magnitude higher than that of AgI-III, and has reached around 0.1 Ω(-1)cm(-1). Evidence for all three, the diffusion coefficient, α and β, and conductivity have proven that AgI-V is a superionic conductor at ambient temperature.

  14. Thermochemical storage for ambient temperatures. Compact seasonal heat storage; Thermochemische opslag bij omgevingstemperatuur. Compacte seizoensopslag van warmte

    Energy Technology Data Exchange (ETDEWEB)

    Wemmers, A.K. [TNO Bouw en Ondergrond, Delft (Netherlands)

    2005-12-01

    The decoupling of demand and production of energy are important aspects in sustainable energy supply systems. Heat storage by commercially available techniques is realized for a temperature level higher than the ambient temperature. Heat loss is the result. By means of thermochemical storage heat can be stored more compact and on the level of ambient temperatures. [Dutch] De ontkoppeling van vraag en de opwekking van energie spelen een belangrijke rol bij de invulling van een duurzame energievoorziening. Opslag van warmte in huidige bekende technieken heeft plaats op een hoger temperatuurniveau dan de omgeving. Met warmteverlies tot gevolg. Met een nieuwe techniek, thermochemische opslag, kan compacter en op omgevingstemperatuurniveau worden opgeslagen.

  15. Rice LTG1 is involved in adaptive growth and fitness under low ambient temperature.

    Science.gov (United States)

    Lu, Guangwen; Wu, Fu-Qing; Wu, Weixun; Wang, Hong-Jun; Zheng, Xiao-Ming; Zhang, Yunhui; Chen, Xiuling; Zhou, Kunneng; Jin, Mingna; Cheng, Zhijun; Li, Xueyong; Jiang, Ling; Wang, Haiyang; Wan, Jianmin

    2014-05-01

    Low temperature (LT) is one of the most prevalent factors limiting the productivity and geographical distribution of rice (Oryza sativa L.). Although significant progress has been made in elucidating the effect of LT on seed germination and reproductive development in rice, the genetic component affecting vegetative growth under LT remains poorly understood. Here, we report that rice cultivars harboring the dominant LTG1 (Low Temperature Growth 1) allele are more tolerant to LT (15-25°C, a temperature range prevalent in high-altitude, temperate zones and high-latitude areas), than those with the ltg1 allele. Using a map-based cloning strategy, we show that LTG1 encodes a casein kinase I. A functional nucleotide polymorphism was identified in the coding region of LTG1, causing a single amino acid substitution (I357K) that is associated with the growth rate, heading date and yield of rice plants grown at LT. We present evidence that LTG1 affects rice growth at LT via an auxin-dependent process(es). Furthermore, phylogenetic analysis of this locus suggests that the ltg1 haplotype arose before the domestication of rice in tropical climates. Together, our data demonstrate that LTG1 plays an important role in the adaptive growth and fitness of rice cultivars under conditions of low ambient temperature.

  16. Preferred ambient temperature for old and young men in summer and winter.

    Science.gov (United States)

    Natsume, K; Ogawa, T; Sugenoya, J; Ohnishi, N; Imai, K

    1992-03-01

    To investigate the effects of age on thermal sensitivity, preferred ambient temperature (Tpref) was compared between old (71-76 years) and young (21-30 years) groups, each consisting of six male subjects in summer and winter. The air temperature (Ta) was set at either 20 degrees C or 40 degrees C at commencement. The subject was directed to adjust the Ta for 45 min by manipulating a remote control switch to the level at which he felt most comfortable. In the older group, the Tpref was significantly lower in trails starting at 20 degrees C than that starting at 40 degrees C in summer. The fluctuation of Tpref (temperature difference between maximum and minimum Ta during the last 10 min) was significantly wider in the older group in both summer and winter. Repetition of the same experiment on each subject showed a poorer reproducibility of Tpref in the older group than in the younger group in summer. Tympanic and esophageal temperatures of the older group kept falling throughout the trial starting at 20 degrees C in summer. These results suggest that thermal sensitivity is decreased with advancing age and that thermal perception in the elderly, especially to cold, is less sensitive in summer.

  17. Ambient temperature dependence on emission spectrum of InAs quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Ngo, C.Y.; Yoon, S.F. [School of Electrical and Electronic Engineering, Nanyang Technological University (Singapore); Chua, S.J. [Institute of Materials Research and Engineering, Faculty of Engineering (Singapore)

    2009-04-15

    Semiconductor superluminescent diodes (SLDs) are important broadband light source for fiber optic gyroscope and biomedical imaging. Quantum dots (QDs) have been proposed to be the best candidate for broadband light sources due to the inhomogeneous broadening of the gain spectrum as a result of the inherited size inhomogeneity of the self-assembled QD growth. In this work, the effect of ambient temperature (25-100 C) on the emission spectrum of InAs QDs with wideband emission was investigated. It was found that the full-width at half-maximum (FWHM) of the photoluminescence (PL) spectra remains more than 125 nm throughout the temperature range, and the redshift as function of temperature is approximately 0.27 meV/K. Activation energy of 270 meV is extracted from the Arrhenius plot and the PL quenching at high temperature is attributed to thermally induced carriers escaping out of the In{sub 0.15}Ga{sub 0.85}As strain-reducing layer. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Influence of Ambient Temperature on the CO2 Emitted With Exhaust Gases of Gasoline Vehicles

    Science.gov (United States)

    Chainikov, D.; Chikishev, E.; Anisimov, I.; Gavaev, A.

    2016-08-01

    This article focuses on the regulation of CO2 emitted in the exhaust gases of gasoline vehicles. Based on comparing the world practices of restrictive measures on greenhouse gas emissions with Russian legislation, we conclude that there is a need to adjust the limits of CO2 emission taking into account the negative impact of ambient temperature on CO2 emission. The climatic conditions of many countries stipulate the use of vehicles in temperatures below zero. At the same time, the existing regulations fully take into account the temperature features of the various countries, which casts doubt on the existence of uniform emission standards for all countries. Here, we conduct an experiment on one of the most popular cars in Russia: the Mitsubishi Lancer 9. We establish that lower temperatures are correlated with larger concentrations of CO2 in the exhaust gases. We draw a conclusion about the need to account for the actual operating conditions when establishing limit values on CO2 emissions of vehicles.

  19. Synthesis of ammonia directly from air and water at ambient temperature and pressure.

    Science.gov (United States)

    Lan, Rong; Irvine, John T S; Tao, Shanwen

    2013-01-01

    The N≡N bond (225 kcal mol⁻¹) in dinitrogen is one of the strongest bonds in chemistry therefore artificial synthesis of ammonia under mild conditions is a significant challenge. Based on current knowledge, only bacteria and some plants can synthesise ammonia from air and water at ambient temperature and pressure. Here, for the first time, we report artificial ammonia synthesis bypassing N₂ separation and H₂ production stages. A maximum ammonia production rate of 1.14 × 10⁻⁵ mol m⁻² s⁻¹ has been achieved when a voltage of 1.6 V was applied. Potentially this can provide an alternative route for the mass production of the basic chemical ammonia under mild conditions. Considering climate change and the depletion of fossil fuels used for synthesis of ammonia by conventional methods, this is a renewable and sustainable chemical synthesis process for future.

  20. Multipole Electrodynamic Ion Trap Geometries for Microparticle Confinement under Standard Ambient Temperature and Pressure Conditions

    CERN Document Server

    Mihalcea, Bogdan M; Stan, Cristina; Visan, Gina T; Ganciu, Mihai; Filinov, Vladimir E; Lapitsky, Dmitry S; Deputatova, Lidiya V; Syrovatka, Roman A

    2015-01-01

    Trapping of microparticles and aerosols is of great interest for physics and chemistry. We report microparticle trapping in multipole linear Paul trap geometries, operating under Standard Ambient Temperature and Pressure (SATP) conditions. An 8-electrode and a 12-electrode linear trap geometries have been designed and tested with an aim to achieve trapping for larger number of particles and to study microparticle dynamical stability in electrodynamic fields. We report emergence of planar and volume ordered structures of the microparticles, depending on the a.c. trapping frequency and particle specific charge ratio. The electric potential within the trap was mapped using the electrolytic tank method. Particle dynamics was simulated using a stochastic Langevin equation. We emphasize extended regions of stable trapping with respect to quadrupole traps, as well as good agreement between experiment and numerical simulations.

  1. Standard test method for ambient temperature fatigue life of metallic bonded resistance strain gages

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2003-01-01

    1.1 This test method covers a uniform procedure for the determination of strain gage fatigue life at ambient temperature. A suggested testing equipment design is included. 1.2 This test method does not apply to force transducers or extensometers that use bonded resistance strain gages as sensing elements. 1.3 Strain gages are part of a complex system that includes structure, adhesive, gage, leadwires, instrumentation, and (often) environmental protection. As a result, many things affect the performance of strain gages, including user technique. A further complication is that strain gages, once installed, normally cannot be reinstalled in another location. Therefore, it is not possible to calibrate individual strain gages; performance characteristics are normally presented on a statistical basis. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices ...

  2. Atomic resolution structure of serine protease proteinase K at ambient temperature

    Science.gov (United States)

    Masuda, Tetsuya; Suzuki, Mamoru; Inoue, Shigeyuki; Song, Changyong; Nakane, Takanori; Nango, Eriko; Tanaka, Rie; Tono, Kensuke; Joti, Yasumasa; Kameshima, Takashi; Hatsui, Takaki; Yabashi, Makina; Mikami, Bunzo; Nureki, Osamu; Numata, Keiji; Iwata, So; Sugahara, Michihiro

    2017-01-01

    Atomic resolution structures (beyond 1.20 Å) at ambient temperature, which is usually hampered by the radiation damage in synchrotron X-ray crystallography (SRX), will add to our understanding of the structure-function relationships of enzymes. Serial femtosecond crystallography (SFX) has attracted surging interest by providing a route to bypass such challenges. Yet the progress on atomic resolution analysis with SFX has been rather slow. In this report, we describe the 1.20 Å resolution structure of proteinase K using 13 keV photon energy. Hydrogen atoms, water molecules, and a number of alternative side-chain conformations have been resolved. The increase in the value of B-factor in SFX suggests that the residues and water molecules adjacent to active sites were flexible and exhibited dynamic motions at specific substrate-recognition sites. PMID:28361898

  3. Ceramic coating of metal by laser heat treatment at ambient pressure and temperature

    Science.gov (United States)

    Picouet, Pierre A.; McStay, Daniel; Hunter, Catherine; Tonge, Kenneth

    2000-02-01

    Initial results for a new laser based procedure to make ceramic coatings on ferrous metals are described. The procedure is performed at ambient temperature and pressure to avoid the use of a vacuum chamber. An Nd:YAG laser beam (1064 nm) coupled to a mechanical scanner is used to produce coating. The coating precursor materials are sprayed onto the metal sample before the laser-generated heat treatment. A jet of argon gas is used to avoid oxidation of the metallic substrate. The principal ingredients of the coating precursor are sodium tetraborate and a natural clay mineral. The product is a glassy ceramic. The product has been characterized by scanning electron microscopy, optical microscopy and hardness and adhesion tests. The results indicate that the surface material is a micrometric, single layer which adheres to the metal surface.

  4. Effect of ambient temperature on species lumping for total organic gases in gasoline exhaust emissions

    Science.gov (United States)

    Roy, Anirban; Choi, Yunsoo

    2017-03-01

    Volatile organic compound (VOCs) emissions from sources often need to be compressed or "lumped" into species classes for use in emissions inventories intended for air quality modeling. This needs to be done to ensure computational efficiency. The lumped profiles are usually reported for one value of ambient temperature. However, temperature-specific detailed profiles have been constructed in the recent past - the current study investigates how the lumping of species from those profiles into different atmospheric chemistry mechanisms is affected by temperature, considering three temperatures (-18 °C, -7 °C and 24 °C). The mechanisms considered differed on the assumptions used for lumping: CB05 (carbon bond type), SAPRC (ozone formation potential) and RACM2 (molecular surrogate and reactivity weighting). In this space, four sub-mechanisms for SAPRC were considered. Scaling factors were developed for each lumped model species and mechanism in terms of moles of lumped species per unit mass. Species which showed a direct one-to-one mapping (SAPRC/RACM2) reported scaling factors that were unchanged across mechanisms. However, CB05 showed different trends since one compound often is mapped onto multiple model species, out of which the paraffinic double bond (PAR) is predominant. Temperature-dependent parameterizations for emission factors pertaining to each lumped species class and mechanism were developed as part of the study. Here, the same kind of model species showed varying lumping parameters across the different mechanisms. These differences could be attributed to differing approaches in lumping. The scaling factors and temperature-dependent parameterizations could be used to update emissions inventories such as MOVES or SMOKE for use in chemical transport modeling.

  5. The Influence of Ambient Temperature on the Susceptibility of Aedes aegypti (Diptera: Culicidae) to the Pyrethroid Insecticide Permethrin.

    Science.gov (United States)

    Whiten, Shavonn R; Peterson, Robert K D

    2016-01-01

    Insecticides are the most common strategy used for the management of mosquitoes. Changes in ambient temperature can alter the toxicity of insecticides to ectothermic organisms. Studies show organophosphate insecticides exhibit a positive correlation between ambient temperature and mortality for many insect species, and carbamate insecticides exhibit a slightly negative correlation between ambient temperature and mortality. Pyrethroid insecticides exhibit a distinctly negative correlation between increasing ambient temperature and mortality for insects. However, this relationship has not been systematically studied for adult mosquitoes. Therefore, we examined the influence of temperature on the susceptibility of adult Aedes aegypti L. (Diptera: Culicidae) when exposed to permethrin. The median lethal concentration, LC50, was estimated for adult Ae. aegypti when exposed to eight concentrations of permethrin (ranging from 0.06–0.58 ng/cm2) at each of the following temperatures—16, 23, 26, 30, 32, and 34C—for 24 h in bottle assays. The estimated LC50 for each temperature was 0.26, 0.36, 0.36, 0.45, 0.27, and 0.31 ng/cm2, respectively. Results indicated a negative correlation between temperature and mortality from 16 to 30C, a positive correlation between temperature and mortality from 30 to 32C, and a negative correlation between temperature and mortality from 32 to 34C. If mosquito populations are expanding in space and time because of increased ambient temperatures and cannot be managed as effectively with pyrethroids, the spread of mosquito-borne diseases may pose considerable additional risk to public health.

  6. Polymer Electrolyte-Based Ambient Temperature Oxygen Microsensors for Environmental Monitoring

    Science.gov (United States)

    Hunter, Gary W.; Xu, Jennifer C.; Liu, Chung-Chiun

    2011-01-01

    An ambient temperature oxygen microsensor, based on a Nafion polymer electrolyte, has been developed and was microfabricated using thin-film technologies. A challenge in the operation of Nafion-based sensor systems is that the conductivity of Nafion film depends on the humidity in the film. Nafion film loses conductivity when the moisture content in the film is too low, which can affect sensor operation. The advancement here is the identification of a method to retain the operation of the Nafion films in lower humidity environments. Certain salts can hold water molecules in the Nafion film structure at room temperature. By mixing salts with the Nafion solution, water molecules can be homogeneously distributed in the Nafion film increasing the film s hydration to prevent Nafion film from being dried out in low-humidity environment. The presence of organics provides extra sites in the Nafion film to promote proton (H+) mobility and thus improving Nafion film conductivity and sensor performance. The fabrication of ambient temperature oxygen microsensors includes depositing basic electrodes using noble metals, and metal oxides layer on one of the electrode as a reference electrode. The use of noble metals for electrodes is due to their strong catalytic properties for oxygen reduction. A conducting polymer Nafion, doped with water-retaining components and extra sites facilitating proton movement, was used as the electrolyte material, making the design adequate for low humidity environment applications. The Nafion solution was coated on the electrodes and air-dried. The sensor operates at room temperature in potentiometric mode, which measures voltage differences between working and reference electrodes in different gases. Repeat able responses to 21-percent oxygen in nitrogen were achieved using nitrogen as a baseline gas. Detection of oxygen from 7 to 21 percent has also been demonstrated. The room-temperature oxygen micro sensor developed has extremely low power

  7. Identification of the Products of Oxidation of Quercetin by Air Oxygenat Ambient Temperature

    Directory of Open Access Journals (Sweden)

    Viktor A Utsal

    2007-03-01

    Full Text Available Oxidation of quercetin by air oxygen takes place in water and aqueous ethanol solutions under mild conditions, namely in moderately-basic media (pH ∼ 8-10 at ambient temperature and in the absence of any radical initiators, without enzymatic catalysis or irradiation of the reaction media by light. The principal reaction products are typical of other oxidative degradation processes of quercetin, namely 3,4-dihydroxy-benzoic (proto-catechuic and 2,4,6-trihydroxybenzoic (phloroglucinic acids, as well as the decarboxylation product of the latter – 1,3,5-trihydroxybenzene (phloroglucinol. In accordance with the literature data, this process involves the cleavage of the γ-pyrone fragment (ring C of the quercetin molecule by oxygen, with primary formation of 4,6-dihydroxy-2-(3,4-dihydroxybenzoyloxybenzoic acid (depside. However under such mild conditions the accepted mechanism of this reaction (oxidative decarbonylation with formation of carbon monoxide, CO should be reconsidered as preferably an oxidative decarboxylation with formation of carbon dioxide, CO2. Direct head-space analysis of the gaseous components formed during quercetin oxidation in aqueous solution at ambient temperature indicates that the ratio of carbon dioxide/carbon monoxide in the gas phase after acidification of the reaction media is ca. 96:4 %. Oxidation under these mild conditions is typical for other flavonols having OH groups at C3 (e.g., kaempferol, but it is completely suppressed if this hydroxyl group is substituted by a glycoside fragment (as in rutin, or a methyl substituent. An alternative oxidation mechanism involving the direct cleavage of the C2-C3 bond in the diketo-tautomer of quercetin is proposed.

  8. The Effect of High Ambient Temperature on the Elderly Population in Three Regions of Sweden

    Directory of Open Access Journals (Sweden)

    Joacim Rocklöv

    2010-06-01

    Full Text Available The short-term effects of high temperatures are a serious concern in the context of climate change. In areas that today have mild climates the research activity has been rather limited, despite the fact that differences in temperature susceptibility will play a fundamental role in understanding the exposure, acclimatization, adaptation and health risks of a changing climate. In addition, many studies employ biometeorological indexes without careful investigation of the regional heterogeneity in the impact of relative humidity. We aimed to investigate the effects of summer temperature and relative humidity and regional differences in three regions of Sweden allowing for heterogeneity of the effect over the scale of summer temperature. To do so, we collected mortality data for ages 65+ from Stockholm, Göteborg and Skåne from the Swedish National Board of Health and Welfare and the Swedish Meteorological and Hydrological Institute for the years 1998 through 2005. In Stockholm and Skåne on average 22 deaths per day occurred, while in Göteborg the mean frequency of daily deaths was 10. We fitted time-series regression models to estimate relative risks of high ambient temperatures on daily mortality using smooth functions to control for confounders, and estimated non-linear effects of exposure while allowing for auto-regressive correlation of observations within summers. The effect of temperature on mortality was found distributed over the same or following day, with statistically significant cumulative combined relative risk of about 5.1% (CI = 0.3, 10.1 per °C above the 90th percentile of summer temperature. The effect of high relative humidity was statistically significant in only one of the regions, as was the effect of relative humidity (above 80th percentile and temperature (above 90th percentile. In the southernmost region studied there appeared to be a significant increase in mortality with decreasing low summer temperatures that was not

  9. Influence of / ratio on rate of chloride induced corrosion of steel reinforcement and its dependence on ambient temperature

    Indian Academy of Sciences (India)

    V Živica

    2003-08-01

    The permeability of the embedding cement material for the rate of chloride induced corrosion when the ambient temperature is increased has found a dominant position. The importance of the given permeability in the process is based on the fact that it represents a factor conditioning the possibility of the escaping of the unambiguous reaction partners, oxygen and water vapour, from the system embedding cement material-steel, as the ambient temperature is increased. The resulting effect is a slowing down of the corrosion rate when the / ratio over the value 0.6 and the ambient temperature over the value 40°C are increased. Due to the similarity of the chemism of the corrosion process of steel reinforcement, independent of the action of aggressive species, the found relationships are generally valid, e.g. for the corrosion due to carbonation.

  10. Cold-start emissions of modern passenger cars at different low ambient temperatures and their evolution over vehicle legislation categories

    Science.gov (United States)

    Weilenmann, Martin; Favez, Jean-Yves; Alvarez, Robert

    The emissions of modern gasoline and diesel passenger cars are reduced by catalysts except in cold-starting. Since catalysts require a certain temperature (typically above 300 °C) to work to full efficiency, emissions are significantly higher during the warm-up phase of the car. The duration of this period and the emissions produced depend on the ambient temperature as well as on the initial temperature of the car's propulsion systems. The additional emissions during a warm-up phase, known as "cold-start extra emissions" (CSEEs) for emission inventory modelling, are mostly assessed by emission measurements at an ambient temperature of 23 °C. However, in many European countries average ambient temperatures are below 23 °C. This necessitates emission measurements at lower temperatures in order to model and assess cold-start emissions for real-world temperature conditions. This paper investigates the influence of regulated pollutants and CO 2 emissions of recent gasoline and diesel car models (Euro-4 legislation) at different ambient temperatures, 23, -7 and -20 °C. We present a survey and model of the evolution of cold-start emissions as a function of different car generations (pre-Euro-1 to Euro-4 legislations). In addition the contribution of CSEEs to total fleet running emissions is shown to highlight their increasing importance. For gasoline cars, it turns out that in average real-world driving the majority of the CO (carbon monoxide) and HC (hydrocarbon) total emissions are due to cold-start extra emissions. Moreover, the cold-start emissions increase considerably at lower ambient temperatures. In contrast, cold-start emissions of diesel cars are significantly lower than those of gasoline cars. Furthermore, the transition from Euro-3 to Euro-4 gasoline vehicles shows a trend for a smaller decline for cold-start extra emissions than for legislative limits. Particle and NO x emission of cold-starts are less significant.

  11. Effects of Ambient Temperature on Growth Performance, Blood Metabolites, and Immune Cell Populations in Korean Cattle Steers.

    Science.gov (United States)

    Kang, H J; Lee, I K; Piao, M Y; Gu, M J; Yun, C H; Kim, H J; Kim, K H; Baik, M

    2016-03-01

    Exposure to cold may affect growth performance in accordance with the metabolic and immunological activities of animals. We evaluated whether ambient temperature affects growth performance, blood metabolites, and immune cell populations in Korean cattle. Eighteen Korean cattle steers with a mean age of 10 months and a mean weight of 277 kg were used. All steers were fed a growing stage-concentrate diet at a rate of 1.5% of body weight and Timothy hay ad libitum for 8 weeks. Experimental period 1 (P1) was for four weeks from March 7 to April 3 and period 2 (P2) was four weeks from April 4 to May 1. Mean (8.7°C) and minimum (1.0°C) indoor ambient temperatures during P1 were lower (pambient temperature affects blood T cell populations. In conclusion, colder ambient temperature decreased growth and feed efficiency in Korean cattle steers. The higher circulating NEFA concentrations observed in March compared to April suggest that lipolysis may occur at colder ambient temperatures to generate heat and maintain body temperature, resulting in lower feed efficiency in March.

  12. Influence of ambient temperature and AC magnetic field on damping behavior of Fe-13Cr-2.5Mo alloy

    Science.gov (United States)

    Xu, Yong-gang; Li, Ning; Shen, Bao-luo; Hua, Hong-xing

    2007-07-01

    The damping behaviors of Fe-13Cr-2.5Mo alloy at ambient temperatures and the AC magnetic field are tested with the improved reversal torsion machine. The precipitations distributing in the annealed alloy are also observed with SEM. The results show that because the defections decrease during the annealing treatment, causing a higher damping capacity of this alloy. This damping drops linearly to 63% when the ambient temperature changes from 23 °C to 500 °C, resulting from the gradual decrease of ferromagnetism. On the other hand, the AC magnetic field causes the damping capacity to drop sharply, and finally it reaches a much lower level.

  13. Association between ambient temperature and acute myocardial infarction hospitalisations in Gothenburg, Sweden: 1985-2010.

    Directory of Open Access Journals (Sweden)

    Janine Wichmann

    Full Text Available Cardiovascular disease (CVD is the number one cause of death globally and evidence is steadily increasing on the role of non-traditional risk factors such as meteorology and air pollution. Nevertheless, many research gaps remain, such as the association between these non-traditional risk factors and subtypes of CVD, such as acute myocardial infarction (AMI. The objective of this study was to investigate the association between daily ambient temperature and AMI hospitalisations using a case-crossover design in Gothenburg, Sweden (1985-2010. A secondary analysis was also performed for out-of-hospital ischemic heart disease (IHD deaths. Susceptible groups by age and sex were explored. The entire year as well as the warm (April-September and cold periods (October-March were considered. In total 28,215 AMI hospitalisations (of 22,475 people and 21,082 out-of-hospital IHD deaths occurred during the 26-year study period. A linear exposure-response corresponding to a 3% and 7% decrease in AMI hospitalisations was observed for an inter-quartile range (IQR increase in the 2-day cumulative average of temperature during the entire year (11°C and the warm period (6°C, respectively, with and without adjustment for PM₁₀, NO₂, NOx or O₃. No heat waves occurred during the warm period. No evidence of an association in the cold period nor any association between temperature and IHD deaths in the entire year, warm or cold periods--with and without adjusting for PM₁₀, NO₂, NOx or O₃ was found. No susceptible groups, based on age or sex, were identified either. The inverse association between temperature and AMI hospitalisations (entire year and warm period in Gothenburg is in accordance with the majority of the few other studies that investigated this subtype of CVD.

  14. Ambient-temperature high damping capacity in TiPd-based martensitic alloys

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Dezhen [Multi-disciplinary Materials Research Center, Frontier Institute of Science and Technology, State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China); Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Zhou, Yumei, E-mail: zhouyumei@mail.xjtu.edu.cn [Multi-disciplinary Materials Research Center, Frontier Institute of Science and Technology, State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China); Ding, Xiangdong [Multi-disciplinary Materials Research Center, Frontier Institute of Science and Technology, State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China); Otsuka, Kazuhiro [Ferroic Physics Group, National Institute for Materials Science, Tsukuba 305-0047, Ibaraki (Japan); Lookman, Turab [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Sun, Jun [Multi-disciplinary Materials Research Center, Frontier Institute of Science and Technology, State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China); Ren, Xiaobing [Multi-disciplinary Materials Research Center, Frontier Institute of Science and Technology, State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China); Ferroic Physics Group, National Institute for Materials Science, Tsukuba 305-0047, Ibaraki (Japan)

    2015-04-24

    Shape memory alloys (SMAs) have attracted considerable attention for their high damping capacities. Here we investigate the damping behavior of Ti{sub 50}(Pd{sub 50−x}D{sub x}) SMAs (D=Fe, Co, Mn, V) by dynamic mechanical analysis. We find that these alloys show remarkably similar damping behavior. There exists a sharp damping peak associated with the B2–B19 martensitic transformation and a high damping plateau (Q{sup −1}~0.02–0.05) over a wide ambient-temperature range (220–420 K) due to the hysteretic twin boundary motion. After doping hydrogen into the above alloys, a new relaxation-type damping peak appears in the martensite phase over 270–360 K. Such a peak is considered to originate from the interaction of hydrogen atoms with twin boundaries and the corresponding damping capacity (Q{sup −1}~0.05–0.09) is enhanced by roughly twice that of the damping plateau for each alloy. Moreover, the relaxation peaks are at higher temperatures for the TiPd-based alloys (270–370 K) than for the TiNi-based alloys (190–260 K). We discuss the influence of hydrogen diffusion, mobility of twin boundaries and hydrogen–twin boundary interaction on the temperature range of the relaxation peak. Our results suggest that a martensite, with appropriate values for twinning shear and hydrogen doping level, provides a route towards developing high damping SMAs for applications in desired temperature ranges.

  15. Screening of agrochemicals in foodstuffs using low-temperature plasma (LTP) ambient ionization mass spectrometry.

    Science.gov (United States)

    Wiley, Joshua S; García-Reyes, Juan F; Harper, Jason D; Charipar, Nicholas A; Ouyang, Zheng; Cooks, R Graham

    2010-05-01

    Low-temperature plasma (LTP) permits direct ambient ionization and mass analysis of samples in their native environment with minimal or no prior preparation. LTP utilizes dielectric barrier discharges (DBDs) to create a low power plasma which is guided by gas flow onto the sample from which analytes are desorbed and ionized. In this study, the potential of LTP-MS for the detection of pesticide residues in food is demonstrated. Thirteen multi-class agricultural chemicals were studied (ametryn, amitraz, atrazine, buprofezin, DEET, diphenylamine, ethoxyquin, imazalil, isofenphos-methyl, isoproturon, malathion, parathion-ethyl and terbuthylazine). To evaluate the potential of the proposed approach, LTP-MS experiments were performed directly on fruit peels as well as on fruit/vegetable extracts. Most of the agrochemicals examined displayed remarkable sensitivity in the positive ion mode, giving limits of detection (LOD) for the direct measurement in the low picogram range. Tandem mass spectrometry (MS/MS) was used to confirm identification of selected pesticides by using for these experiments spiked fruit/vegetable extracts (QuEChERS, a standard sample treatment protocol) at levels as low as 1 pg, absolute, for some of the analytes. Comparisons of the data obtained by direct LTP-MS were made with the slower but more accurate conventional LC-MS/MS procedure. Herbicides spiked in aqueous solutions were detectable at LODs as low as 0.5 microg L(-1) without the need for any sample preparation. The results demonstrate that ambient LTP-MS can be applied for the detection and confirmation of traces of agrochemicals in actual market-purchased produce and in natural water samples. Quantitative analysis was also performed in a few selected cases and displayed a relatively high degree of linearity over four orders of magnitude.

  16. Real-World Emission of Particles from Vehicles: Volatility and the Effects of Ambient Temperature.

    Science.gov (United States)

    Wang, Jonathan M; Jeong, Cheol-Heon; Zimmerman, Naomi; Healy, Robert M; Hilker, Nathan; Evans, Greg J

    2017-03-16

    A majority of the ultrafine particles observed in real-world conditions are systematically excluded from many measurements that help to guide regulation of vehicle emissions. To investigate the impact of this exclusion, coincident near-road particle number (PN) emission factors were quantified up- and downstream of a thermodenuder during two seasonal month-long campaigns with wide-ranging ambient temperatures (-19 to +30 °C) to determine the volatile fraction of particles. During colder temperatures (20 °C). Additionally, mean PN emission factors were a factor of 3.8 higher during cold compared to warm periods. On the basis of 130 000 vehicle plumes including three additional campaigns, fleet mean emission factors were calculated for PN (8.5 × 10(14) kg-fuel(-1)), black carbon (37 mg kg-fuel(-1)), organic aerosol (51 mg kg-fuel(-1)), and particle-bound polycyclic aromatic hydrocarbons (0.7 mg kg-fuel(-1)). These findings demonstrate that significant differences exist between particles in thermally treated vehicle exhaust as compared to in real-world vehicle plumes to which populations in near-road environments are actually exposed. Furthermore, the magnitude of these differences are dependent upon season and may be more extreme in colder climates.

  17. Non-contact skin emissivity: measurement from reflectance using step change in ambient radiation temperature.

    Science.gov (United States)

    Togawa, T

    1989-02-01

    A method of estimating skin emissivity based on reflectance measurement upon transient stepwise change in the ambient radiation temperature was proposed. To effect this change, two shades at different temperatures were switched mechanically, and the change in radiation from the skin surface was recorded through an aperture for each shade by a high-resolution, fast-response radiometer having a sensitivity within the 8-14 microns range. Measurements were made on the forehead, forearm, palm and back of the hand in 10 male and 10 female subjects. No significant differences in emissivity were observed among sites and between sexes. The overall average of the skin emissivity obtained was 0.971 +/- 0.005 (SD). This result is inconsistent with most reported skin emissivity values. However, as the former studies had many inherent inadequacies, both theoretical and experimental, it is considered that most of these reported skin emissivities are unacceptable. The method proposed in this study has the following advantages: (1) relative calibration between instruments is unnecessary, (2) non-contact measurement can be achieved, and (3) each measurement can be made within one minute.

  18. THE INFLUENCE OF OBESITY AND AMBIENT TEMPERATURE ON PHYSIOLOGICAL AND OXIDATIVE RESPONSES TO SUBMAXIMAL EXERCISE

    Science.gov (United States)

    Ahn, N.

    2014-01-01

    This study investigated the effects of obesity and ambient temperature on physiological responses and markers of oxidative stress to submaximal exercise in obese and lean people. Sixteen healthy males were divided into an obese group (n=8, %fat: 27.00±3.00%) and a lean group (n=8, %fat: 13.85±2.45%). Study variables were measured during a 60 min submaximal exercise test at 60% VO2max in a neutral (21±1°C) and a cold (4±1°C) environment. Heart rate, blood lactate, rectal temperature, serum levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were measured at rest, during exercise and in recovery. Heart rate of both groups was significantly lower (P<0.05) in the cold than the warm environment, but there were no significant differences between the two groups. Serum SOD activity increased to a significantly greater extent (P<0.05) in the cold than the neutral environment, and remained elevated for longer during exercise in the obese group than the lean group. Serum MDA level during submaximal exercise was not significantly different between conditions or groups. Cold stress in exercise may challenge antioxidant defence mechanisms in obese subjects, but lipid peroxidation remains unchanged. PMID:24899779

  19. Systematic effects from an ambient-temperature, continuously-rotating half-wave plate

    CERN Document Server

    Essinger-Hileman, T; Appel, J W; Choi, S K; Crowley, K; Jarosik, N; Page, L A; Parker, L P; Raghunathan, S; Simon, S M; Staggs, S T; Visnjic, K

    2016-01-01

    We present an evaluation of systematic effects associated with a continuously-rotating, ambient-temperature half-wave plate (HWP) based on two seasons of data from the Atacama B-Mode Search (ABS) experiment located in the Atacama Desert of Chile. The ABS experiment is a microwave telescope sensitive at 145 GHz. The HWP allows for rejection of unpolarized atmospheric fluctuations and ground pickup, as well as clear separation of celestial polarization from intensity. In a previous paper, we demonstrated 30 dB rejection of atmospheric fluctuations on timescales of 500 s. Here we present our in-field evaluation of celestial (CMB plus galactic foreground) temperature-to-polarization leakage. We decompose the leakage into scalar, dipole, and quadrupole leakage terms. We report a scalar leakage of ~0.01%, consistent with model expectations and an order of magnitude smaller than other CMB experiments have reported. No significant dipole or quadruple terms are detected; we constrain each to be < 0.06% (95% confide...

  20. Systematic effects from an ambient-temperature, continuously rotating half-wave plate

    Science.gov (United States)

    Essinger-Hileman, T.; Kusaka, A.; Appel, J. W.; Choi, S. K.; Crowley, K.; Ho, S. P.; Jarosik, N.; Page, L. A.; Parker, L. P.; Raghunathan, S.; Simon, S. M.; Staggs, S. T.; Visnjic, K.

    2016-09-01

    We present an evaluation of systematic effects associated with a continuously rotating, ambient-temperature half-wave plate (HWP) based on two seasons of data from the Atacama B-Mode Search (ABS) experiment located in the Atacama Desert of Chile. The ABS experiment is a microwave telescope sensitive at 145 GHz. Here we present our in-field evaluation of celestial (Cosmic Microwave Background (CMB) plus galactic foreground) temperature-to-polarization leakage. We decompose the leakage into scalar, dipole, and quadrupole leakage terms. We report a scalar leakage of ˜0.01%, consistent with model expectations and an order of magnitude smaller than other CMB experiments have been reported. No significant dipole or quadrupole terms are detected; we constrain each to be ABS survey and focal-plane layout before any data correction such as so-called deprojection. This demonstrates that ABS achieves significant beam systematic error mitigation from its HWP and shows the promise of continuously rotating HWPs for future experiments.

  1. Electric battery cell, system and method. [ambient temperature, dithionite salt in electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, R.E.

    1979-05-15

    An ambient-temperature electric cell of primary and secondary nature, characterized by the use of the dithionite salt of an active (alkali or an alkaline earth) metal as the charging agent, is described along with processes for manufacturing and for operating it. The dithionite salt is dissolved and suspended in an anhydrous electrolyte comprised of a suitable solvent, which may also contain another salt of the same active metal and may be saturated with sulfur dioxide. To form the cell, a sealed and evacuated enclosure having a negative electrode and a positive current-gathering electrode is filled with the electrolyte and subjected to a charging current sufficient to plate the active metal onto the negative electrode, while the positive electrode is saturated with sulfur dioxide. In the case of a secondary cell, the dithionite produced upon discharge is available as a partially dissolved and suspended salt in the electrolyte. Such availability may be enhanced by a system for forced circulation of the electrolyte. In the case of a primary cell, the final cell potential and discharge characteristics may be enhanced by replacing the dithionite electrolyte with other anhydrous electrolyte solutions (e.g., sulfuryl chloride or thionyl chloride) once the lithium has been plated out. The cell is characterized by extremely low internal resistance, long shelf life, and excellent performance over a wide temperature range. 72 claims.

  2. Synthesis of indium nanoparticles at ambient temperature; simultaneous phase transfer and ripening

    Science.gov (United States)

    Aghazadeh Meshgi, Mohammad; Kriechbaum, Manfred; Biswas, Subhajit; Holmes, Justin D.; Marschner, Christoph

    2016-12-01

    The synthesis of size-monodispersed indium nanoparticles via an innovative simultaneous phase transfer and ripening method is reported. The formation of nanoparticles occurs in a one-step process instead of well-known two-step phase transfer approaches. The synthesis involves the reduction of InCl3 with LiBH4 at ambient temperature and although the reduction occurs at room temperature, fine indium nanoparticles, with a mean diameter of 6.4 ± 0.4 nm, were obtained directly in non-polar n-dodecane. The direct synthesis of indium nanoparticles in n-dodecane facilitates their fast formation and enhances their size-monodispersity. In addition, the nanoparticles were highly stable for more than 2 months. The nanoparticles were characterised by dynamic light scattering (DLS), small angle X-ray scattering (SAXS), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS) and Fourier transform infrared (FT-IR) spectroscopy to determine their morphology, structure and phase purity.

  3. Formic Acid Dehydrogenation on Au-Based Catalysts at Near-Ambient Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Ojeda, Manuel; Iglesia, Enrique

    2008-11-24

    Formic acid (HCOOH) is a convenient hydrogen carrier in fuel cells designed for portable use. Recent studies have shown that HCOOH decomposition is catalyzed with Ru-based complexes in the aqueous phase at near-ambient temperatures. HCOOH decomposition reactions are used frequently to probe the effects of alloying and cluster size and of geometric and electronic factors in catalysis. These studies have concluded that Pt is the most active metal for HCOOH decomposition, at least as large crystallites and extended surfaces. The identity and oxidation state of surface metal atoms influence the relative rates of dehydrogenation (HCOOH {yields} H{sub 2} + CO{sub 2}) and dehydration (HCOOH {yields} H{sub 2}O + CO) routes, a selectivity requirement for the synthesis of CO-free H{sub 2} streams for low-temperature fuel cells. Group Ib and Group VIII noble metals catalyze dehydrogenation selectively, while base metals and metal oxides catalyze both routes, either directly or indirectly via subsequent water-gas shift (WGS) reactions.

  4. Nocturnal loss of body reserves reveals high survival risk for subordinate great tits wintering at extremely low ambient temperatures.

    Science.gov (United States)

    Krams, Indrikis; Cīrule, Dina; Vrublevska, Jolanta; Nord, Andreas; Rantala, Markus J; Krama, Tatjana

    2013-06-01

    Winter acclimatization in birds is a complex of several strategies based on metabolic adjustment accompanied by long-term management of resources such as fattening. However, wintering birds often maintain fat reserves below their physiological capacity, suggesting a cost involved with excessive levels of reserves. We studied body reserves of roosting great tits in relation to their dominance status under two contrasting temperature regimes to see whether individuals are capable of optimizing their survival strategies under extreme environmental conditions. We predicted less pronounced loss of body mass and body condition and lower rates of overnight mortality in dominant great tits at both mild and extremely low ambient temperatures, when ambient temperature dropped down to -43 °C. The results showed that dominant great tits consistently maintained lower reserve levels than subordinates regardless of ambient temperature. However, dominants responded to the rising risk of starvation under low temperatures by increasing their body reserves, whereas subdominant birds decreased reserve levels in harsh conditions. Yet, their losses of body mass and body reserves were always lower than in subordinate birds. None of the dominant great tits were found dead, while five young females and one adult female were found dead in nest boxes during cold spells when ambient temperatures dropped down to -43 °C. The dead great tits lost up to 23.83 % of their evening body mass during cold nights while surviving individuals lost on average 12.78 % of their evening body mass. Our results show that fattening strategies of great tits reflect an adaptive role of winter fattening which is sensitive to changes in ambient temperatures and differs among individuals of different social ranks.

  5. High performance PEMFC stack with open-cathode at ambient pressure and temperature conditions

    Energy Technology Data Exchange (ETDEWEB)

    Santa Rosa, D.T.; Pinto, D.G.; Silva, V.S. [SRE - Solucoes Racionais de Energia, S.A., Poligono Industrial do Alto do Ameal, Ramalhal (Portugal); Silva, R.A.; Rangel, C.M. [INETI, Unidade de Electroquimica de Materiais, Lisboa (Portugal)

    2007-12-15

    An open-air cathode proton exchange membrane fuel cell (PEMFC) was developed. This paper presents a study of the effect of several critical operating conditions on the performance of an 8-cell stack. The studied operating conditions such as cell temperature, air flow rate and hydrogen pressure and flow rate were varied in order to identify situations that could arise when the PEMFC stack is used in low-power portable PEMFC applications. The stack uses an air fan in the edge of the cathode manifolds, combining high stoichiometric oxidant supply and stack cooling purposes. In comparison with natural convection air-breathing stacks, the air dual-function approach brings higher stack performances, at the expense of having a lower use of the total stack power output. Although improving the electrochemical reactions kinetics and decreasing the polarization effects, the increase of the stack temperature lead to membrane excessive dehydration (loss of sorbed water), increasing the ohmic resistance of the stack (lower performance). The results show that the stack outputs a maximum power density of 310mW/cm{sup 2} at 790mA/cm{sup 2} when operating at ambient temperature, atmospheric air pressure, self-humidifying, air fan voltage at 5.0 V and 250 mbar hydrogen relative pressure. For the studied range of hydrogen relative pressure (150-750 mbar), it is found that the stack performance is practically not affected by this operation condition, although a slightly higher power output for 150 mbar was observed. On the other hand, it is found that the stack performance increases appreciably when operated with forced air convection instead of natural convection. Finally, the continuous fuel flow operation mode does not improve the stack performance in comparison with the hydrogen dead-end mode, in spite of being preferable to operate the stack with hydrogen flow rates above 0.20 l/min. (author)

  6. Staying cool in a changing landscape: the influence of maximum daily ambient temperature on grizzly bear habitat selection.

    Science.gov (United States)

    Pigeon, Karine E; Cardinal, Etienne; Stenhouse, Gordon B; Côté, Steeve D

    2016-08-01

    To fulfill their needs, animals are constantly making trade-offs among limiting factors. Although there is growing evidence about the impact of ambient temperature on habitat selection in mammals, the role of environmental conditions and thermoregulation on apex predators is poorly understood. Our objective was to investigate the influence of ambient temperature on habitat selection patterns of grizzly bears in the managed landscape of Alberta, Canada. Grizzly bear habitat selection followed a daily and seasonal pattern that was influenced by ambient temperature, with adult males showing stronger responses than females to warm temperatures. Cutblocks aged 0-20 years provided an abundance of forage but were on average 6 °C warmer than mature conifer stands and 21- to 40-year-old cutblocks. When ambient temperatures increased, the relative change (odds ratio) in the probability of selection for 0- to 20-year-old cutblocks decreased during the hottest part of the day and increased during cooler periods, especially for males. Concurrently, the probability of selection for 21- to 40-year-old cutblocks increased on warmer days. Following plant phenology, the odds of selecting 0- to 20-year-old cutblocks also increased from early to late summer while the odds of selecting 21- to 40-year-old cutblocks decreased. Our results demonstrate that ambient temperatures, and therefore thermal requirements, play a significant role in habitat selection patterns and behaviour of grizzly bears. In a changing climate, large mammals may increasingly need to adjust spatial and temporal selection patterns in response to thermal constraints.

  7. High ambient temperature increases 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy")-induced Fos expression in a region-specific manner.

    Science.gov (United States)

    Hargreaves, G A; Hunt, G E; Cornish, J L; McGregor, I S

    2007-03-16

    3,4-Methylenedioxymethamphetamine (MDMA, "Ecstasy") is a popular drug that is often taken under hot conditions at dance clubs. High ambient temperature increases MDMA-induced hyperthermia and recent studies suggest that high temperatures may also enhance the rewarding and prosocial effects of MDMA in rats. The present study investigated whether ambient temperature influences MDMA-induced expression of Fos, a marker of neural activation. Male Wistar rats received either MDMA (10 mg/kg i.p.) or saline, and were placed in test chambers for 2 h at either 19 or 30 degrees C. MDMA caused significant hyperthermia at 30 degrees C and a modest hypothermia at 19 degrees C. The 30 degrees C ambient temperature had little effect on Fos expression in vehicle-treated rats. However MDMA-induced Fos expression was augmented in 15 of 30 brain regions at the high temperature. These regions included (1) sites associated with thermoregulation such as the median preoptic nucleus, dorsomedial hypothalamus and raphe pallidus, (2) the supraoptic nucleus, a region important for osmoregulation and a key mediator of oxytocin and vasopressin release, (3) the medial and central nuclei of the amygdala, important in the regulation of social and emotional behaviors, and (4) the shell of the nucleus accumbens and (anterior) ventral tegmental area, regions associated with the reinforcing effects of MDMA. MDMA-induced Fos expression was unaffected by ambient temperature at many other sites, and was diminished at high temperature at one site (the islands of Calleja), suggesting that the effect of temperature on MDMA-induced Fos expression was not a general pharmacokinetic effect. Overall, these results indicate that high temperatures accentuate key neural effects of MDMA and this may help explain the widespread use of the drug under hot conditions at dance parties as well as the more hazardous nature of MDMA taken under such conditions.

  8. Sloths like it hot: ambient temperature modulates food intake in the brown-throated sloth (Bradypus variegatus).

    Science.gov (United States)

    Cliffe, Rebecca N; Haupt, Ryan J; Avey-Arroyo, Judy A; Wilson, Rory P

    2015-01-01

    Sloths are considered to have one of the lowest mass-specific metabolic rates of any mammal and, in tandem with a slow digestive rate, have been theorized to have correspondingly low rates of ingestion. Here, we show in a study conducted over five months, that three captive Bradypus variegatus (Brown-throated sloths) had a remarkably low mean food intake of 17 g kg(-1)day(-1) (SD 4.2). Food consumption was significantly affected by ambient temperature, with increased intake at higher temperatures. We suggest that the known fluctuation of sloth core body temperature with ambient temperature affects the rate at which gut fauna process digesta, allowing for increased rates of fermentation at higher temperatures. Since Bradypus sloths maintain a constantly full stomach, faster rates of fermentation should enhance digestive throughput, increasing the capacity for higher levels of food intake, thereby allowing increased energy acquisition at higher ambient temperatures. This contrasts with other mammals, which tend to show increased levels of food intake in colder conditions, and points to the importance of temperature in regulating all aspects of energy use in sloths.

  9. Sloths like it hot: ambient temperature modulates food intake in the brown-throated sloth (Bradypus variegatus

    Directory of Open Access Journals (Sweden)

    Rebecca N. Cliffe

    2015-04-01

    Full Text Available Sloths are considered to have one of the lowest mass-specific metabolic rates of any mammal and, in tandem with a slow digestive rate, have been theorized to have correspondingly low rates of ingestion. Here, we show in a study conducted over five months, that three captive Bradypus variegatus (Brown-throated sloths had a remarkably low mean food intake of 17 g kg−1day−1 (SD 4.2. Food consumption was significantly affected by ambient temperature, with increased intake at higher temperatures. We suggest that the known fluctuation of sloth core body temperature with ambient temperature affects the rate at which gut fauna process digesta, allowing for increased rates of fermentation at higher temperatures. Since Bradypus sloths maintain a constantly full stomach, faster rates of fermentation should enhance digestive throughput, increasing the capacity for higher levels of food intake, thereby allowing increased energy acquisition at higher ambient temperatures. This contrasts with other mammals, which tend to show increased levels of food intake in colder conditions, and points to the importance of temperature in regulating all aspects of energy use in sloths.

  10. A note on eating behaviour of dairy cows at different stocking systems - diurnal rhythm and effects of ambient temperature

    NARCIS (Netherlands)

    Taweel, H.Z.; Tas, B.M.; Smit, H.J.; Tamminga, S.; Elgersma, A.

    2006-01-01

    This experiment was aimed at studying the diurnal rhythm of dairy cows eating behaviour at different stocking systems, and quantifying the effect of daily ambient temperature on this diurnal rhythm. In two experiments carried out in the summer of 2003 in The Netherlands, eight dairy cows were offere

  11. Influence of variable heat transfer coefficient of fireworks and crackers on thermal explosion critical ambient temperature and time to ignition

    OpenAIRE

    Guo Zerong; Xia Quan; Yan Peiyu; Du Zhiming

    2016-01-01

    To study the effect of variable heat transfer coefficient of fireworks and crackers on thermal explosion critical ambient temperature and time to ignition, considering the heat transfer coefficient as the power function of temperature, mathematical thermal explosion steady state and unsteady-state model of finite cylindrical fireworks and crackers with complex shell structures are established based on two-dimensional steady state thermal explosion theory. T...

  12. Pelage insulation, litter size, and ambient temperature impact maternal energy intake and offspring development during lactation.

    Science.gov (United States)

    Paul, Matthew J; Tuthill, Christiana; Kauffman, Alexander S; Zucker, Irving

    2010-05-11

    Energy balance during lactation critically influences survival and growth of a mother's offspring, and hence, her reproductive success. Most experiments have investigated the influence of a single factor (e.g., ambient temperature [T(a)] or litter size) on the energetics of lactation. Here, we determined the impact of multiple interventions, including increased conductive heat loss consequent to dorsal fur removal, cold exposure (T(a) of 5 degrees C versus 23 degrees C), and differential lactational load from litters of different sizes (2 or 4 pups), on maternal energy balance and offspring development of Siberian hamsters (Phodopus sungorus). Lower T(a), fur removal, and larger litters were associated with increased maternal food consumption. Females exposed to multiple challenges (e.g., both fur loss and lower T(a)) ate substantially more food than those exposed to a single challenge, with no apparent ceiling to elevated food intake (increases up to 538%). Thus, energy intake of dams under these conditions does not appear to be limited by feeding behavior or the size of the digestive tract. Housing at 5 degrees C attenuated pup weight gain and increased pup mortality to more than 5 times that of litters housed at 23 degrees C. Increases in the dam's conductive heat loss induced by fur removal did not affect pup weight gain or survival, suggesting that effects of low T(a) on pup weight gain and survival reflect limitations in the pups' ability to ingest or incorporate energy.

  13. Fatty acid composition of ewe milk as affected by solar radiation and high ambient temperature.

    Science.gov (United States)

    Sevi, Agostino; Rotunno, Taddeo; Di Roberto, Caterina; Muscio, Antonio

    2002-05-01

    Forty lactating Comisana ewes were either exposed to or protected from solar radiation and fed either in the morning or afternoon during summer in a Mediterranean climate. Individual milk samples were taken on days 7, 21 and 42 of the study period to determine fatty acid composition by gas chromatography. Exposure to solar radiation resulted in higher proportions of short-chain and saturated fatty acids in milk, primarily because of increased contents of caproic, capric, lauric, myristic and stearic acids (by 3-18%), and decreased contents of oleic, linoleic and linolenic acids (by 2-9%). As a consequence, the long to short chain and the unsaturated to saturated fatty acid ratios were significantly higher by 4 and 13% respectively in the milk of the protected ewes compared with that of the exposed animals. Provision of shade also led to an increase in the 18:0+18:1 to 16:0 ratio, and to a decrease in the 12:0 + 14:0 + 16:0 fatty acid group, which are regarded as reliable indexes of the nutritional property of dietary fat in reducing cholesterol levels in human plasma. Feeding time had little impact on milk fat. Our findings suggest that high ambient temperature may markedly modify the lipid composition of ewe milk and that provision of shade, but not feeding management, can improve the milk fatty acid profile in dairy sheep raised in hot climates.

  14. Examination of design options for 35 Ah ambient temperature Li-TiS sub 2 cells

    Science.gov (United States)

    Shen, D. H.; Rao, S. S.; Yen, S. P. S.; Somoano, R. B.

    1986-01-01

    The Jet Propulsion Laboratory is actively engaged in the development of ambient temperature rechargable lithium cells for future NASA geosynchronous Earth orbit (GEO) missions. To achieve these ambitious goals, Li-TiS2, Li-MoS3, and Li-V6O13 systems were examined in detail. Among these three, the Li-TiS2 system has shown the longest life cycle and highest rate capability. Experimental Li-TiS2 batteries (10.5 V, 0.4 Ah) developed in-house have completed eight simulated and accelerated GEO seasons successfully. Inview of the encouraging results, the design options were examined for a scaled-up Li-TiS2 cell. It is hoped that the results of these studies will provide guidelines for prioritizing the research efforts and guiding the selection of optimized materials. Designs for 35 Ah Li-TiS2 cell were examined because present day geosynchronous satellites are powered by batteries of 35 Ah capacity. A computer program was developed to evaluate the influence of various design parameters on the specific energy and the rate capability of the cells.

  15. Activated carbon catalyzed persulfate oxidation of Azo dye acid orange 7 at ambient temperature.

    Science.gov (United States)

    Yang, Shiying; Yang, Xin; Shao, Xueting; Niu, Rui; Wang, Leilei

    2011-02-15

    Persulfate (PS) oxidative degradation of azo dye acid orange 7 (AO7) in an aqueous solution was studied in the presence of suspended granular activated carbon (GAC) at ambient temperature (e.g., 25°C). It was observed that there existed a remarkable synergistic effect in the GAC/PS combined system. Higher PS concentration and GAC dosage resulted in higher AO7 degrading rates. Near-neutral was the optimal initial pH. Adsorption had an adverse effect on AO7 degradation. AO7 had not only a good decolorization, but a good mineralization. The decomposition of PS followed a first-order kinetics behavior both in the presence and in the absence of AO7. Radical mechanism was studied and three radical scavengers (methanol (MA), tert-butanol (TBA), phenol) were used to determine the kind of major active species taking part in the degradation of AO7 and the location of degradation reaction. It was assumed that the degradation of AO7 did not occur in the liquid phase, but in the porous bulk and boundary layer on the external surface of GAC. SO(4)(-•) or HO•, generated on or near the surface of GAC, played a major role in the AO7 degradation. Finally, the recovery performance of GAC was studied through the GAC reuse experiments.

  16. Strength and Density of Geopolymer Mortar Cured at Ambient Temperature for Use as Repair Material

    Science.gov (United States)

    Warid Wazien, A. Z.; Bakri Abdullah, Mohd Mustafa Al; Abd. Razak, Rafiza; Mohd Remy Rozainy, M. A. Z.; Faheem Mohd Tahir, Muhammad

    2016-06-01

    Geopolymers produced by synthesizing aluminosilicate source materials with an alkaline activator solution promised an excellent properties akin to the existing construction material. This study focused on the effect of various binder to sand ratio on geopolymer mortar properties. Mix design of geopolymer mortar was produced using NaOH concentration of 12 molars, ratio of fly ash/alkaline activator and ratio Na2SiO3/NaOH of 2.0 and 2.5 respectively. Samples subsequently ware cured at ambient temperature. The properties of geopolymer mortar were analysed in term of compressive strength and density at different period which are on the 3rd and 7th day of curing. Experimental results revealed that the addition of sand slightly increase the compressive strength of geopolymer. The optimum compressive strength obtained was up to 31.39 MPa on the 7th day. The density of geopolymer mortar was in the range between 2.0 g/cm3 to 2.23 g/cm3. Based on this findings, the special properties promoted by geopolymer mortar display high potential to be implemented in the field of concrete patch repair.

  17. Male weasels decrease activity and energy expenditure in response to high ambient temperatures.

    Directory of Open Access Journals (Sweden)

    Karol Zub

    Full Text Available The heat dissipation limit (HDL hypothesis suggests that the capacity of endotherms to dissipate body heat may impose constraints on their energy expenditure. Specifically, this hypothesis predicts that endotherms should avoid the detrimental consequences of hyperthermia by lowering their energy expenditure and reducing their activity in response to high ambient temperatures (T(a. We used an extensive data set on the daily energy expenditure (DEE, n = 27 and the daily activity time (AT, n = 48 of male weasels (Mustela nivalis during the spring and summer breeding season to test these predictions. We found that T(a was related in a "hump-shaped" (i.e. convex manner to AT, DEE, resting metabolic rate (RMR and metabolic scope (the ratio of DEE to RMR. These results support the HDL hypothesis because in response to warm Tas male weasels reduced their AT, DEE, and RMR. Although the activity and energy expenditure of large endotherms are most likely to be constrained in response to warm Tas because they are less able to dissipate heat, our results suggest that small endotherms may also experience constraints consistent with the HDL hypothesis.

  18. Short-term preservation of porcine oocytes in ambient temperature: novel approaches.

    Directory of Open Access Journals (Sweden)

    Cai-Rong Yang

    Full Text Available The objective of this study was to evaluate the feasibility of preserving porcine oocytes without freezing. To optimize preservation conditions, porcine cumulus-oocyte complexes (COCs were preserved in TCM-199, porcine follicular fluid (pFF and FCS at different temperatures (4°C, 20°C, 25°C, 27.5°C, 30°C and 38.5°C for 1 day, 2 days or 3 days. After preservation, oocyte morphology, germinal vesicle (GV rate, actin cytoskeleton organization, cortical granule distribution, mitochondrial translocation and intracellular glutathione level were evaluated. Oocyte maturation was indicated by first polar body emission and spindle morphology after in vitro culture. Strikingly, when COCs were stored at 27.5°C for 3 days in pFF or FCS, more than 60% oocytes were still arrested at the GV stage and more than 50% oocytes matured into MII stages after culture. Almost 80% oocytes showed normal actin organization and cortical granule relocation to the cortex, and approximately 50% oocytes showed diffused mitochondria distribution patterns and normal spindle configurations. While stored in TCM-199, all these criteria decreased significantly. Glutathione (GSH level in the pFF or FCS group was higher than in the TCM-199 group, but lower than in the non-preserved control group. The preserved oocytes could be fertilized and developed to blastocysts (about 10% with normal cell number, which is clear evidence for their retaining the developmental potentiality after 3d preservation. Thus, we have developed a simple method for preserving immature pig oocytes at an ambient temperature for several days without evident damage of cytoplasm and keeping oocyte developmental competence.

  19. Temperature-induced volatility of molecular markers in ambient airborne particulate matter

    Directory of Open Access Journals (Sweden)

    C. R. Ruehl

    2010-08-01

    Full Text Available Molecular markers are organic compounds used to represent known sources of particulate matter (PM in statistical source apportionment studies. The utility of molecular markers depends on, among other things, their ability to represent PM volatility under realistic atmospheric conditions. We measured the particle-phase concentrations and temperature-induced volatility of commonly-used molecular markers in California's heavily polluted San Joaqin Valley. Concentrations of elemental carbon, organic carbon, levoglucosan, and polycyclic aromatic hydrocarbons were not reduced by mild (~10 K heating. In contrast, both hopane/sterane and n-alkane concentrations were reduced, especially during the summer sampling events at the urban site. These results suggest that hopanes and steranes have effective saturation concentrations ~1 μg m−3, and therefore can be considered semi-volatile in realistic ambient conditions. The volatility behavior of n-alkanes during the urban summer is consistent with that predicted for absorption by suberic acid (a C8 diacid using a group contribution modelling method. Observations can also be matched by an absorbent whose composition is based on recently-obtained high-resolution aerosol mass spectrometer factors (approximately 33% "hydrocarbon-like" and 67% oxygenated organic aerosol. The diminished volatility of the n-alkanes, hopanes, and steranes during rural and/or winter experiments could be explained by a more oxygenated absorbing phase along with a non-absorptive partitioning mechanism, such as adsorption to soot. This suggests that the temperature-induced volatility of large hydrocarbons in PM is most important if a relatively non-polar absorbing organic phase exists. While the activity coefficients of most organic aerosol compounds may be close to unity, the assumption of ideality for large hydrocarbons (e.g., hopanes may result in large errors in partitioning calculations.

  20. Entrainment of the circadian clock by daily ambient temperature cycles in the camel (Camelus dromedarius).

    Science.gov (United States)

    El Allali, Khalid; Achaâban, Mohamed R; Bothorel, Béatrice; Piro, Mohamed; Bouâouda, Hanan; El Allouchi, Morad; Ouassat, Mohammed; Malan, André; Pévet, Paul

    2013-06-01

    In mammals the light-dark (LD) cycle is known to be the major cue to synchronize the circadian clock. In arid and desert areas, the camel (Camelus dromedarius) is exposed to extreme environmental conditions. Since wide oscillations of ambient temperature (Ta) are a major factor in this environment, we wondered whether cyclic Ta fluctuations might contribute to synchronization of circadian rhythms. The rhythm of body temperature (Tb) was selected as output of the circadian clock. After having verified that Tb is synchronized by the LD and free runs in continuous darkness (DD), we submitted the animals to daily cycles of Ta in LL and in DD. In both cases, the Tb rhythm was entrained to the cycle of Ta. On a 12-h phase shift of the Ta cycle, the mean phase shift of the Tb cycle ranged from a few hours in LD (1 h by cosinor, 4 h from curve peaks) to 7-8 h in LL and 12 h in DD. These results may reflect either true synchronization of the central clock by Ta daily cycles or possibly a passive effect of Ta on Tb. To resolve the ambiguity, melatonin rhythmicity was used as another output of the clock. In DD melatonin rhythms were also entrained by the Ta cycle, proving that the daily Ta cycle is able to entrain the circadian clock of the camel similar to photoperiod. By contrast, in the presence of a LD cycle the rhythm of melatonin was modified by the Ta cycle in only 2 (or 3) of 7 camels: in these specific conditions a systematic effect of Ta on the clock could not be evidenced. In conclusion, depending on the experimental conditions (DD vs. LD), the daily Ta cycle can either act as a zeitgeber or not.

  1. Small-capacity valve-regulated lead/acid battery with long life at high ambient temperature

    Energy Technology Data Exchange (ETDEWEB)

    Hatanaka, T.; Maeda, M.; Iwata, M. [Battery Development Center, Japan Storage Battery, Kyoto (Japan)

    1998-05-18

    Valve-regulated lead/acid (VRLA) batteries are widely used as back-up power sources for telecommunications and UPS. These applications require high-reliability under severe environmental conditions. To meet this demand, the authors` company have developed small capacity (12 V, 15-65 A h at C{sub 20}/20 rate), long-life VRLA batteries which can endure high ambient temperature. These batteries make use of a new alloy and grid design which has improved resistance to corrosion at the positive plate, while at the same time reduce float current at high temperature. As a result, these batteries have a life expectancy of 13 years at 25 C, and inhibited thermal runaway even under ambient temperatures up to 75 C. The batteries can be installed in outdoor and underground environments. (orig.)

  2. A Combined State of Charge Estimation Method for Lithium-Ion Batteries Used in a Wide Ambient Temperature Range

    Directory of Open Access Journals (Sweden)

    Fei Feng

    2014-05-01

    Full Text Available Ambient temperature is a significant factor that influences the characteristics of lithium-ion batteries, which can produce adverse effects on state of charge (SOC estimation. In this paper, an integrated SOC algorithm that combines an advanced ampere-hour counting (Adv Ah method and multistate open-circuit voltage (multi OCV method, denoted as “Adv Ah + multi OCV”, is proposed. Ah counting is a simple and general method for estimating SOC. However, the available capacity and coulombic efficiency in this method are influenced by the operating states of batteries, such as temperature and current, thereby causing SOC estimation errors. To address this problem, an enhanced Ah counting method that can alter the available capacity and coulombic efficiency according to temperature is proposed during the SOC calculation. Moreover, the battery SOCs between different temperatures can be mutually converted in accordance with the capacity loss. To compensate for the accumulating errors in Ah counting caused by the low precision of current sensors and lack of accurate initial SOC, the OCV method is used for calibration and as a complement. Given the variation of available capacities at different temperatures, rated/non-rated OCV–SOCs are established to estimate the initial SOCs in accordance with the Ah counting SOCs. Two dynamic tests, namely, constant- and alternated-temperature tests, are employed to verify the combined method at different temperatures. The results indicate that our method can provide effective and accurate SOC estimation at different ambient temperatures.

  3. Cobalt promoted copper manganese oxide catalysts for ambient temperature carbon monoxide oxidation.

    Science.gov (United States)

    Jones, Christopher; Taylor, Stuart H; Burrows, Andrew; Crudace, Mandy J; Kiely, Christopher J; Hutchings, Graham J

    2008-04-14

    Low levels of cobalt doping (1 wt%) of copper manganese oxide enhances its activity for carbon monoxide oxidation under ambient conditions and the doped catalyst can display higher activity than current commercial catalysts.

  4. Reactor Design for CO2 Photo-Hydrogenation toward Solar Fuels under Ambient Temperature and Pressure

    Directory of Open Access Journals (Sweden)

    Chun-Ying Chen

    2017-02-01

    Full Text Available Photo-hydrogenation of carbon dioxide (CO2 is a green and promising technology and has received much attention recently. This technique could convert solar energy under ambient temperature and pressure into desirable and sustainable solar fuels, such as methanol (CH3OH, methane (CH4, and formic acid (HCOOH. It is worthwhile to mention that this direction can not only potentially depress atmospheric CO2, but also weaken dependence on fossil fuel. Herein, 1 wt % Pt/CuAlGaO4 photocatalyst was successfully synthesized and fully characterized by ultraviolet-visible light (UV-vis spectroscopy, X-ray diffraction (XRD, Field emission scanning electron microscopy using energy dispersive spectroscopy analysis (FE-SEM/EDS, transmission electron microscopy (TEM, X-ray photoelectron spectroscopy (XPS, and Brunauer-Emmett-Teller (BET, respectively. Three kinds of experimental photo-hydrogenation of CO2 in the gas phase, liquid phase, and gas-liquid phase, correspondingly, were conducted under different H2 partial pressures. The remarkable result has been observed in the gas-liquid phase. Additionally, increasing the partial pressure of H2 would enhance the yield of product. However, when an extra amount of H2 is supplied, it might compete with CO2 for occupying the active sites, resulting in a negative effect on CO2 photo-hydrogenation. For liquid and gas-liquid phases, CH3OH is the major product. Maximum total hydrocarbons 8.302 µmol·g−1 is achieved in the gas-liquid phase.

  5. Estrous cycle fluctuations in sex and ingestive behavior are accentuated by exercise or cold ambient temperatures.

    Science.gov (United States)

    Abdulhay, Amir; Benton, Noah A; Klingerman, Candice M; Krishnamoorthy, Kaila; Brozek, Jeremy M; Schneider, Jill E

    2014-06-01

    This article is part of a Special Issue "Energy Balance". In female Syrian hamsters (Mesocricetus auratus), low circulating levels of ovarian steroids are associated with increased food hoarding and decreased sexual motivation, but these effects are exaggerated in food-restricted females. To determine whether cold ambient temperature has the same effects as food restriction, groups of hamsters were fed ad libitum while they were housed at either 5 °C or 22 °C, and then tested for behavior for 90 min on each day of the estrous cycle. In females housed at 22 °C, high levels of sexual motivation and low levels of food hoarding were seen every day of the estrous cycle. In females housed at 5 °C, high levels of sexual motivation were restricted to the periovulatory day. On the three nonestrous days, these females showed high levels of food hoarding, but not food intake. A separate cohort of females were provided with access to running wheels and housed at 22 °C. They showed high levels of sexual motivation restricted to the periovulatory day, similar to the pattern of sexual motivation seen in cold-housed females. Unlike cold-housed females, those with running wheels showed low levels of food hoarding and high levels of food intake. Food restriction, cold housing, and access to wheels had no significant effect on plasma estradiol or progesterone concentrations, but significantly decreased plasma leptin concentrations. All three energetic challenges unmask estrous cycle fluctuations in sexual motivation that are obscured in laboratory conditions, i.e., isolation in a small cage with an overabundance of food.

  6. High ambient temperature reverses hypothalamic MC4 receptor overexpression in an animal model of anorexia nervosa.

    Science.gov (United States)

    Gutiérrez, E; Churruca, I; Zárate, J; Carrera, O; Portillo, M P; Cerrato, M; Vázquez, R; Echevarría, E

    2009-04-01

    The potential involvement of the melanocortin system in the beneficial effects of heat application in rats submitted to activity-based anorexia (ABA), an analogous model of anorexia nervosa (AN), was studied. Once ABA rats had lost 20% of body weight, half of the animals were exposed to a high ambient temperature (HAT) of 32 degrees C, whereas the rest were maintained at 21 degrees C. Control sedentary rats yoked to ABA animals received the same treatment. ABA rats (21 degrees C) showed increased Melanocortin 4 (MC4) receptor and Agouti gene Related Peptide (AgRP) expression, and decreased pro-opiomelanocortin (POMC) mRNA levels (Real Time PCR), with respect to controls. Heat application increased weight gain and food intake, and reduced running rate in ABA rats, when compared with ABA rats at 21 degrees C. However, no changes in body weight and food intake were observed in sedentary rats exposed to heat. Moreover, heat application reduced MC4 receptor, AgRP and POMC expression in ABA rats, but no changes were observed in control rats. These results indicate that hypothalamic MC4 receptor overexpression could occur on the basis of the characteristic hyperactivity, weight loss, and self-starvation of ABA rats, and suggest the involvement of hypothalamic melanocortin neural circuits in behavioural changes shown by AN patients. Changes in AgRP and POMC expression could represent an adaptative response to equilibrate energy balance. Moreover, the fact that HAT reversed hypothalamic MC4 receptor overexpression in ABA rats indicates the involvement of brain melanocortin system in the reported beneficial effects of heat application in AN. A combination of MC4 receptor antagonists and heat application could improve the clinical management of AN.

  7. Experimental Investigation of the Effect of Change in Ambient Air Temperature on Power Consumption of Domestic Refrigerators

    Directory of Open Access Journals (Sweden)

    J. A. Olorunmaiye

    2012-12-01

    Full Text Available One of the manifestations of climate change is increase.in ambient air temperature usually referred to as global warming. For sustainable development in a country, there is need to identify impacts of climate change and the necessary adaptation and mitigation strategies to adopt. To simulate the effect of global warming on the power consumption of refrigerators, a (model No. 150 THERMOCOOL refrigerator filled with twenty-five 750cl packaged water bottleswas run in an air-conditioned room, in a room with the air-conditioner switched off and near an oven in a bakery. The electric power consumption of the refrigerator was measured using "Watts up?.net" Watt meter and the ambient temperature was measured using FLUKE temperature/humidity meter. The average hourly energy consumption of the refrigerator operating at mean ambient temperatures of 25.4°C, 30.7oC, 38.8°C were 93.844 Wh, 100.32 Wh and 105.08 Wh respectively. Some possible ways to reduce the increase in power consumption of refrigerators due to global warming include using compressors of higher efficiency and condensers of greater effectiveness.

  8. Structural Studies of NH4-exchanged Natrolites at Ambient Conditions and High Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Y Lee; D Seoung; Y Jang; J Bai; Y Lee

    2011-12-31

    We report here for the first time that fully and partially NH{sub 4}-exchanged natrolites can be prepared in hydrated states using the solution exchange method with potassium-natrolite. The structural models of the as-prepared hydrated phases and their dehydrated forms at elevated temperature were refined in space group Fdd2 using in situ synchrotron X-ray powder diffraction data and Rietveld methods. The unit-cell volumes of the hydrated NH{sub 4}-exchanged natrolites at ambient conditions, (NH{sub 4}){sub 16(2)}Al{sub 16}Si{sub 24}O{sub 80}{center_dot}14.1(9)H{sub 2}O and (NH{sub 4}){sub 5.1(1)}K{sub 10.9(1)}Al{sub 16}Si{sub 24}O{sub 80}{center_dot}15.7(3)H{sub 2}O, are found to be larger than that the original sodium-natrolite by ca. 15.6% and 12.8%, respectively. Upon temperature increase, the fully NH{sub 4}-exchanged natrolite undergoes dehydration at ca. 150 C with ca. 16.4% contraction in the unit-cell volume. The dehydrated phase of the fully NH{sub 4}-exchanged natrolite exhibits marginal volume expansion up to 425 C and then becomes amorphized during temperature decrease and exposure to atmospheric condition. In the case of the partially NH{sub 4}-exchanged natrolite, the dehydration starts from ca. 175 C with {approx}15.1% volume contraction and leads to a partial phase separation to show a phase related to the dehydrated K-natrolite. The degree of the phase separation decreases with temperature increase up to 475 C, concomitant to the gradual volume contraction occurring in the partially NH{sub 4}-exchanged natrolite in the dehydrared state. Upon temperature decrease and exposure to atmospheric condition, only the dehydrated K-natrolite is recovered as a crystalline phase from the partially NH{sub 4}-exchanged natrolite. In the hydrated model of the fully NH{sub 4}-exchanged natrolite, the ammonium cations and water molecules are statistically distributed along the elliptical channels, similar to the disordered pattern observed in natrolites exchanged

  9. Ambient Air Temperature Does Not Predict whether Small or Large Workers Forage in Bumble Bees (Bombus impatiens

    Directory of Open Access Journals (Sweden)

    Margaret J. Couvillon

    2010-01-01

    Full Text Available Bumble bees are important pollinators of crops and other plants. However, many aspects of their basic biology remain relatively unexplored. For example, one important and unusual natural history feature in bumble bees is the massive size variation seen between workers of the same nest. This size polymorphism may be an adaptation for division of labor, colony economics, or be nonadaptive. It was also suggested that perhaps this variation allows for niche specialization in workers foraging at different temperatures: larger bees might be better suited to forage at cooler temperatures and smaller bees might be better suited to forage at warmer temperatures. This we tested here using a large, enclosed growth chamber, where we were able to regulate the ambient temperature. We found no significant effect of ambient or nest temperature on the average size of bees flying to and foraging from a suspended feeder. Instead, bees of all sizes successfully flew and foraged between 16∘C and 36∘C. Thus, large bees foraged even at very hot temperatures, which we thought might cause overheating. Size variation therefore could not be explained in terms of niche specialization for foragers at different temperatures.

  10. Energy from Biomass - Comparision of biogas production at ambient temperature and at mesophilic temperature in semicontenous anaerobic digester using vegetable market waste

    Directory of Open Access Journals (Sweden)

    Dhanalakshmi Sridevi V.

    2014-03-01

    Full Text Available Studies are conducted in semicontinuous anaerobic reactors of 2 L Capacity with effective volume of 1.5 L. Experiments were carried out in the mesophilic temperature range maintained at 35°C in a thermostat, and parallel experiments were performed at ambient temperature on biogas production from the month of Februray to August. The reactors were operated with an organic loading rate of 0.5 gVS/L/d with 25 days HRT. The feed stock used for the study was vegetable market waste obtained from Koyambedu vegetable market. The specific biogas production was found to be 0.530 L gVS add-1 for the reactor operated at mesophilic temperature and in the range of 0.431 to 0.732 L gVSadd -1 for the reactor operated in the ambient temperature condition from the month of February to August. The daily biogas production was found to be similar (approximately 350 mL/d when reactors were operated at mesophilic and ambient temperature except for the period of May and June wherein higher amount of daily biogas production (472 and 529 mL/d was observed in the reactor operated at ambient temperature. The ratio of total VFA and alkalinity and propionic acid to acetic acid (PA/AA was found to be in the range of 0.25 – 0.4 and 0.34 - 1.38 during the operation of the reactor for the entire period, which was within the range reported for digester stability.

  11. The influence of internal and skin temperatures on active cutaneous vasodilation under different levels of exercise and ambient temperatures in humans

    Science.gov (United States)

    Demachi, Koichi; Yoshida, Tetsuya; Kume, Masashi; Tsuji, Michio; Tsuneoka, Hideyuki

    2013-07-01

    To clarify the influence of internal and skin temperature on the active cutaneous vasodilation during exercise, the body temperature thresholds for the onset of active vasodilation during light or moderate exercise under different ambient temperature conditions were compared. Seven male subjects performed 30 min of a cycling exercise at 20 % or 50 % of peak oxygen uptake in a room maintained at 20, 24, or 28 °C. Esophageal (Tes) and mean skin temperature (Tsk) as measured by a thermocouple, deep thigh temperature (Tdt) by the zero-heat-flow (ZHF) method, and forearm skin blood flow by laser-Doppler flowmetry (LDF) were monitored. The mean arterial pressure (MAP) was also monitored non-invasively, and the cutaneous vascular conductance (CVC) was calculated as the LDF/MAP. Throughout the experiment, the Tsk at ambient temperatures of 20, 24, and 28 °C were approximately 30, 32, and 34 °C, respectively, for both 20 % and 50 % exercise. During 50 % exercise, the Tes or Tdt thresholds for the onset of the increase in CVC were observed to be similar among the 20, 24, and 28 °C ambient conditions. During 20 % exercise, the increase in Tes and Tdt was significantly lower than those found at 50 %, and the onset of the increase in CVC was only observed at 28 °C. These results suggest that the onset of active vasodilation was affected more strongly by the internal or exercising tissue temperatures than by the skin temperatures during exercise performed at a moderate load in comparison to a light load under Tsk variations ranging from 30 °C to 34 °C. Therefore, the modification by skin temperature of the central control on cutaneous vasomotor tone during exercise may differ between different exercise loads.

  12. Effect of ambient temperature on nutrient digestibility and nitrogen balance in sheep fed brown-midrib maize silage.

    Science.gov (United States)

    Gorniak, Tobias; Meyer, Ulrich; Südekum, Karl-Heinz; Dänicke, Sven

    2014-01-01

    The aim of the experiment was to determine the impact of heat stress on nutrient digestibility and nitrogen balance in sheep fed silages differing in fibre quality. The digestibility trial was conducted at three different ambient temperatures (15°C, 25°C and 35°C for 24 h/d). The tested brown-midrib maize (Bm) silage had a higher nutrient digestibility, except for ether extract (EE) and a higher metabolisable energy (ME) content than the control maize (Con) silage. Nitrogen (N) excretion with faeces was higher but N excretion with urine was lower for sheep fed Bm silage, subsequently N balance did not differ between the two silages. Temperature had no effect on nutrient digestibility, except for crude protein (CP), but N excretion with urine was lower at elevated temperatures. A diet by temperature interaction was found for dry matter (DM) and organic matter (OM) digestibility. When the ambient temperature increased from 15°C to 25°C, the DM and OM digestibility increased in animals fed Con silage, but decreased in animals fed Bm silage. Concomitantly, ME estimated from digestible nutrients was higher for Bm than for Con at 15°C, but no differences were found at 25°C and 35°C. Effects of diet by temperature interaction, furthermore, were observed for EE and CP digestibility. Therefore, forage quality has to be considered when feeding heat-stressed animals.

  13. Effect of different arbuscular mycorrhizal fungi on growth and physiology of maize at ambient and low temperature regimes

    DEFF Research Database (Denmark)

    Chen, Xiaoying; Song, Fengbin; Liu, Fulai;

    2014-01-01

    The effect of four different arbuscular mycorrhizal fungi (AMF) on the growth and lipid peroxidation, soluble sugar, proline contents, and antioxidant enzymes activities of Zea mays L. was studied in pot culture subjected to two temperature regimes. Maize plants were grown in pots filled...... with a mixture of sandy and black soil for 5 weeks, and then half of the plants were exposed to low temperature for 1 week while the rest of the plants were grown under ambient temperature and severed as control. Different AMF resulted in different root colonization and low temperature significantly decreased AM...... colonization. Low temperature remarkably decreased plant height and total dry weight but increased root dry weight and root-shoot ratio. The AM plants had higher proline content compared with the non-AM plants. The maize plants inoculated with Glomus etunicatum and G. intraradices had higher malondialdehyde...

  14. Sow and litter response to supplemental dietary fat in lactation diets during high ambient temperatures.

    Science.gov (United States)

    Rosero, D S; van Heugten, E; Odle, J; Cabrera, R; Arellano, C; Boyd, R D

    2012-02-01

    The objective of this experiment was to determine the impact of supplemental dietary fat on total lactation energy intake and sow and litter performance during high ambient temperatures (27 ± 3°C). Data were collected from 337 mixed-parity sows from July to September in a 2,600-sow commercial unit in Oklahoma. Diets were corn-soybean meal-based with 7.5% corn distillers dried grains with solubles and 6.0% wheat middlings and contained 3.24 g of standardized ileal digestible Lys/Mcal of ME. Animal-vegetable fat blend (A-V) was supplemented at 0, 2, 4, or 6%. Sows were balanced by parity, with 113, 109, and 115 sows representing parity 1, 2, and 3 to 7 (P3+), respectively. Feed disappearance (subset of 190 sows; 4.08, 4.18, 4.44, and 4.34 kg/d, for 0, 2, 4, and 6%, respectively; P feed (sow and litter BW gain relative to feed intake) was not affected (P = 0.56), but gain:Mcal ME declined linearly with the addition of A-V (0.16, 0.15, 0.15, and 0.14 for 0, 2, 4, and 6%, respectively; P sows (3.95 kg/d) had less (P feed disappearance than P2 (4.48 kg/d) and P3+ (4.34 kg/d) sows. Body weight change in P1 sows was greater (P sows (-0.32 vs. -0.07 and 0.12 kg/d), whereas backfat loss was less (P sows compared with P1 and P2 sows. Dietary A-V improved litter ADG (P sows. Sows bred within 8 d after weaning (58.3, 72.0, 70.2, and 74.7% for 0, 2, 4, and 6%, respectively); conception rate (78.5, 89.5, 89.2, and 85.7%) and farrowing rate (71.4, 81.4, 85.5, and 78.6%) were improved (P sows were greater (P sows had lower (P sows, and respiration rate was reduced (P sows compared with P2 and P3+ sows. In conclusion, A-V improved feed disappearance and caloric intake, resulting in improved litter weight gain and subsequent reproductive performance of sows; however, feed and caloric efficiency were negatively affected.

  15. Testing an e2v CCD230-42 sensor for dark current performance at ambient temperatures - Final Paper

    Energy Technology Data Exchange (ETDEWEB)

    Dungee, Ryan [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-20

    The design of the Guidance Focus and Alignment (GFA) system for the Dark Energy Spectroscopic Instrument (DESI) project calls for a set of charge-coupled devices (CCDs) which operate at ambient temperature. Here we assess the performance of these CCDs under such conditions. Data was collected from –21°C to 28°C and used to determine the effect of temperature on the effectiveness of dark current subtraction. Comparing the dark current uncertainty to our expected signal has shown that the DESI design specifications will be met without need for significant changes.

  16. Efficient and high yield one-pot synthesis of cyclometalated platinum(II) β-diketonates at ambient temperature.

    Science.gov (United States)

    Hudson, Zachary M; Blight, Barry A; Wang, Suning

    2012-04-06

    Cyclometalated Pt(II) β-diketonates are widely used as efficient luminescent materials but are typically prepared at high temperatures in low yields using excess reagents. A one-pot synthesis of these complexes is described employing stoichiometric reagents and short reaction times at ambient temperature, giving yields of up to 94%. The method is applicable to a broad range of substrates including N^C, P^C, and C^C chelate Pt(II) complexes and different β-diketonate ligands.

  17. Ambient temperature effects on photo induced gonadal cycles and hormonal secretion patterns in Great Tits from three different breeding latitudes.

    Science.gov (United States)

    Silverin, Bengt; Wingfield, John; Stokkan, Karl-Arne; Massa, Renato; Järvinen, Antero; Andersson, Nils-Ake; Lambrechts, Marcel; Sorace, Alberto; Blomqvist, Donald

    2008-06-01

    The present study determines how populations of Great Tits (Parus major) breeding in southern, mid and northern European latitudes have adjusted their reproductive endocrinology to differences in the ambient temperature during the gonadal cycle. A study based on long-term breeding data, using the Colwell predictability model, showed that the start of the breeding season has a high predictability ( approximately 0.8-0.9) at all latitudes, and that the environmental information factor (I(e)) progressively decreased from mid Italy (I(e)>4) to northern Finland (I(e)Tits from northern Norway, southern Sweden and northern Italy to sub-maximal photo-stimulatory day lengths (13L:11D) under two different ambient temperature regimes (+4 degrees C and +20 degrees C). Changes in testicular size, plasma levels of LH and testosterone were measured. The main results were: (1) Initial testicular growth rate, as well as LH secretion, was affected by temperature in the Italian, but not in birds from the two Scandinavian populations. (2) Maximum testicular size, maximum LH and testosterone levels were maintained for a progressively shorter period of time with increasing latitude, regardless of whether the birds were kept on a low or a high ambient temperature. (3) In birds from all latitudes, the development of photorefractoriness, as indicated by testicular regression and a decrease in plasma levels of LH and testosterone, started much earlier (with the exception for LH Great Tits from northern Scandinavia) when kept on +20 degrees C than when kept on +4 degrees C. The prolonging effects of a low temperature was more pronounced in Mediterranean birds, than in birds from Scandinavia, and more pronounced in Great Tits from southern Scandinavia than in Great Tits from northern Scandinavia. Ecological implications of the results are discussed, as well as possible impact of global warming on the breeding success of European Great Tits from different breeding latitudes.

  18. The embryonic life history of the tropical sea hare Stylocheilus striatus (Gastropoda: Opisthobranchia) under ambient and elevated ocean temperatures.

    Science.gov (United States)

    Horwitz, Rael; Jackson, Matthew D; Mills, Suzanne C

    2017-01-01

    Ocean warming represents a major threat to marine biota worldwide, and forecasting ecological ramifications is a high priority as atmospheric carbon dioxide (CO2) emissions continue to rise. Fitness of marine species relies critically on early developmental and reproductive stages, but their sensitivity to environmental stressors may be a bottleneck in future warming oceans. The present study focuses on the tropical sea hare, Stylocheilus striatus (Gastropoda: Opisthobranchia), a common species found throughout the Indo-West Pacific and Atlantic Oceans. Its ecological importance is well-established, particularly as a specialist grazer of the toxic cyanobacterium, Lyngbya majuscula. Although many aspects of its biology and ecology are well-known, description of its early developmental stages is lacking. First, a detailed account of this species' life history is described, including reproductive behavior, egg mass characteristics and embryonic development phases. Key developmental features are then compared between embryos developed in present-day (ambient) and predicted end-of-century elevated ocean temperatures (+3 °C). Results showed developmental stages of embryos reared at ambient temperature were typical of other opisthobranch species, with hatching of planktotrophic veligers occurring 4.5 days post-oviposition. However, development times significantly decreased under elevated temperature, with key embryonic features such as the velum, statocysts, operculum, eyespots and protoconch developing approximately 24 h earlier when compared to ambient temperature. Although veligers hatched one day earlier under elevated temperature, their shell size decreased by approximately 20%. Our findings highlight how an elevated thermal environment accelerates planktotrophic development of this important benthic invertebrate, possibly at the cost of reducing fitness and increasing mortality.

  19. The embryonic life history of the tropical sea hare Stylocheilus striatus (Gastropoda: Opisthobranchia) under ambient and elevated ocean temperatures

    Science.gov (United States)

    Jackson, Matthew D.; Mills, Suzanne C.

    2017-01-01

    Ocean warming represents a major threat to marine biota worldwide, and forecasting ecological ramifications is a high priority as atmospheric carbon dioxide (CO2) emissions continue to rise. Fitness of marine species relies critically on early developmental and reproductive stages, but their sensitivity to environmental stressors may be a bottleneck in future warming oceans. The present study focuses on the tropical sea hare, Stylocheilus striatus (Gastropoda: Opisthobranchia), a common species found throughout the Indo-West Pacific and Atlantic Oceans. Its ecological importance is well-established, particularly as a specialist grazer of the toxic cyanobacterium, Lyngbya majuscula. Although many aspects of its biology and ecology are well-known, description of its early developmental stages is lacking. First, a detailed account of this species’ life history is described, including reproductive behavior, egg mass characteristics and embryonic development phases. Key developmental features are then compared between embryos developed in present-day (ambient) and predicted end-of-century elevated ocean temperatures (+3 °C). Results showed developmental stages of embryos reared at ambient temperature were typical of other opisthobranch species, with hatching of planktotrophic veligers occurring 4.5 days post-oviposition. However, development times significantly decreased under elevated temperature, with key embryonic features such as the velum, statocysts, operculum, eyespots and protoconch developing approximately 24 h earlier when compared to ambient temperature. Although veligers hatched one day earlier under elevated temperature, their shell size decreased by approximately 20%. Our findings highlight how an elevated thermal environment accelerates planktotrophic development of this important benthic invertebrate, possibly at the cost of reducing fitness and increasing mortality. PMID:28168118

  20. The embryonic life history of the tropical sea hare Stylocheilus striatus (Gastropoda: Opisthobranchia under ambient and elevated ocean temperatures

    Directory of Open Access Journals (Sweden)

    Rael Horwitz

    2017-02-01

    Full Text Available Ocean warming represents a major threat to marine biota worldwide, and forecasting ecological ramifications is a high priority as atmospheric carbon dioxide (CO2 emissions continue to rise. Fitness of marine species relies critically on early developmental and reproductive stages, but their sensitivity to environmental stressors may be a bottleneck in future warming oceans. The present study focuses on the tropical sea hare, Stylocheilus striatus (Gastropoda: Opisthobranchia, a common species found throughout the Indo-West Pacific and Atlantic Oceans. Its ecological importance is well-established, particularly as a specialist grazer of the toxic cyanobacterium, Lyngbya majuscula. Although many aspects of its biology and ecology are well-known, description of its early developmental stages is lacking. First, a detailed account of this species’ life history is described, including reproductive behavior, egg mass characteristics and embryonic development phases. Key developmental features are then compared between embryos developed in present-day (ambient and predicted end-of-century elevated ocean temperatures (+3 °C. Results showed developmental stages of embryos reared at ambient temperature were typical of other opisthobranch species, with hatching of planktotrophic veligers occurring 4.5 days post-oviposition. However, development times significantly decreased under elevated temperature, with key embryonic features such as the velum, statocysts, operculum, eyespots and protoconch developing approximately 24 h earlier when compared to ambient temperature. Although veligers hatched one day earlier under elevated temperature, their shell size decreased by approximately 20%. Our findings highlight how an elevated thermal environment accelerates planktotrophic development of this important benthic invertebrate, possibly at the cost of reducing fitness and increasing mortality.

  1. Biodegradation of Synthetic Polyesters (BTA and PCL with Natural Flora in Soil Burial and Pure Cultures under Ambient Temperature

    Directory of Open Access Journals (Sweden)

    Mona K. Gouda

    2012-03-01

    Full Text Available The aim of this study was to study the biodegradation of two synthetic polyesters, one aliphaticaromatic (1, 4-butanediol, terephthalic-adipic acid, BTA and the other aliphatic (poly (,-caprolactone, PCL, under different soil types (canal shore soil, garden soil, compost and Peat moss, respectively, as well as using locally isolated cultures at ambient temperature. The results showed that the BTA films buried in canal shore and garden soil were degraded faster than that in the other soils. After six weeks about 90, 88 and 80% were degraded in garden, canal shore soil and compost respectively, while only 52% were degraded in Peat moss. On the other hand, 95 and 93% weight loss was obtained for PCL films buried for three weeks in canal shore and garden soil respectively. The Scanning Electron Microscope photos confirm the results of weight loss and revealed the presence of cracks and fungal growth on films buried in different soils. The results with pure cultures, especially with Fusarium solani, also confirmed the biodegradability of two polyesters under ambient temperature. Finally, it could be concluded that both synthetic polyester are degradable under ambient conditions.

  2. Splashing phenomena of room temperature liquid metal droplet striking on the pool of the same liquid under ambient air environment

    CERN Document Server

    Li, Haiyan; Wang, Lei; Gao, Yunxia; Liu, Jing

    2013-01-01

    In this article, the fluid dynamics of room temperature liquid metal (RTLM) droplet impacting onto a pool of the same liquid in ambient air was investigated. A series of experiments were conducted in order to disclose the influence of the oxidation effect on the impact dynamics. The droplet shape and impact phenomenology were recorded with the aid of a high-speed digital camera. The impact energy stored in the splash structures was estimated via a theoretical model and several morphological parameters obtained from instantaneous images of the splash. It was observed that the droplet shape and the splashing morphology of RTLM were drastically different from those of water, so was the impact dynamics between room temperature LM pool and high temperature LM pool. The energy analysis disclosed that the height of the jet is highly sensitive to the viscosity of the fluid, which is subjected to the oxidation effect and temperature effect simultaneously, and thus perfectly explained the phenomena. These basic finding...

  3. Thermal degradation of concrete in the temperature range from ambient to 315{degrees}C (600{degrees}F)

    Energy Technology Data Exchange (ETDEWEB)

    Kassir, M.K.; Bandyopadhyay, K.K.; Reich, M.

    1993-06-01

    This report is concerned with determining the effect of elevated temperatures on the behavior of concrete. Emphasis is placed on quantifying the degree of potential degradation of the physical properties of concrete in high-level waste storage tanks. The range in the temperature elevation of interest covers from ambient to 315{degrees}C (600{degrees}F). The literature has been reviewed to examine the applicable experimental data and quantify the degradation in the concrete and reinforcing steel. Since many variables and test conditions control the results in the data base, upper and lower bounds of the degraded properties at temperatures applicable to the environments of the storage tanks are summarized and presented in explicit forms. Such results are useful in assessing the effect of elevated temperatures on the structural behavior of the tanks. Also, they provide the technical basis for a parametric study that may be necessary to investigate the thermal aspects of the structural integrity of the tanks.

  4. Responses of wheat and rice to factorial combinations of ambient and elevated CO2 and temperature in FACE experiments.

    Science.gov (United States)

    Cai, Chuang; Yin, Xinyou; He, Shuaiqi; Jiang, Wenyu; Si, Chuanfei; Struik, Paul C; Luo, Weihong; Li, Gang; Xie, Yingtian; Xiong, Yan; Pan, Genxing

    2016-02-01

    Elevated CO2 and temperature strongly affect crop production, but understanding of the crop response to combined CO2 and temperature increases under field conditions is still limited while data are scarce. We grew wheat (Triticum aestivum L.) and rice (Oryza sativa L.) under two levels of CO2 (ambient and enriched up to 500 μmol mol(-1) ) and two levels of canopy temperature (ambient and increased by 1.5-2.0 °C) in free-air CO2 enrichment (FACE) systems and carried out a detailed growth and yield component analysis during two growing seasons for both crops. An increase in CO2 resulted in higher grain yield, whereas an increase in temperature reduced grain yield, in both crops. An increase in CO2 was unable to compensate for the negative impact of an increase in temperature on biomass and yield of wheat and rice. Yields of wheat and rice were decreased by 10-12% and 17-35%, respectively, under the combination of elevated CO2 and temperature. The number of filled grains per unit area was the most important yield component accounting for the effects of elevated CO2 and temperature in wheat and rice. Our data showed complex treatment effects on the interplay between preheading duration, nitrogen uptake, tillering, leaf area index, and radiation-use efficiency, and thus on yield components and yield. Nitrogen uptake before heading was crucial in minimizing yield loss due to climate change in both crops. For rice, however, a breeding strategy to increase grain number per m(2) and % filled grains (or to reduce spikelet sterility) at high temperature is also required to prevent yield reduction under conditions of global change.

  5. Effect of different arbuscular mycorrhizal fungi on growth and physiology of maize at ambient and low temperature regimes.

    Science.gov (United States)

    Chen, Xiaoying; Song, Fengbin; Liu, Fulai; Tian, Chunjie; Liu, Shengqun; Xu, Hongwen; Zhu, Xiancan

    2014-01-01

    The effect of four different arbuscular mycorrhizal fungi (AMF) on the growth and lipid peroxidation, soluble sugar, proline contents, and antioxidant enzymes activities of Zea mays L. was studied in pot culture subjected to two temperature regimes. Maize plants were grown in pots filled with a mixture of sandy and black soil for 5 weeks, and then half of the plants were exposed to low temperature for 1 week while the rest of the plants were grown under ambient temperature and severed as control. Different AMF resulted in different root colonization and low temperature significantly decreased AM colonization. Low temperature remarkably decreased plant height and total dry weight but increased root dry weight and root-shoot ratio. The AM plants had higher proline content compared with the non-AM plants. The maize plants inoculated with Glomus etunicatum and G. intraradices had higher malondialdehyde and soluble sugar contents under low temperature condition. The activities of catalase (CAT) and peroxidase of AM inoculated maize were higher than those of non-AM ones. Low temperature noticeably decreased the activities of CAT. The results suggest that low temperature adversely affects maize physiology and AM symbiosis can improve maize seedlings tolerance to low temperature stress.

  6. Effect of Different Arbuscular Mycorrhizal Fungi on Growth and Physiology of Maize at Ambient and Low Temperature Regimes

    Directory of Open Access Journals (Sweden)

    Xiaoying Chen

    2014-01-01

    Full Text Available The effect of four different arbuscular mycorrhizal fungi (AMF on the growth and lipid peroxidation, soluble sugar, proline contents, and antioxidant enzymes activities of Zea mays L. was studied in pot culture subjected to two temperature regimes. Maize plants were grown in pots filled with a mixture of sandy and black soil for 5 weeks, and then half of the plants were exposed to low temperature for 1 week while the rest of the plants were grown under ambient temperature and severed as control. Different AMF resulted in different root colonization and low temperature significantly decreased AM colonization. Low temperature remarkably decreased plant height and total dry weight but increased root dry weight and root-shoot ratio. The AM plants had higher proline content compared with the non-AM plants. The maize plants inoculated with Glomus etunicatum and G. intraradices had higher malondialdehyde and soluble sugar contents under low temperature condition. The activities of catalase (CAT and peroxidase of AM inoculated maize were higher than those of non-AM ones. Low temperature noticeably decreased the activities of CAT. The results suggest that low temperature adversely affects maize physiology and AM symbiosis can improve maize seedlings tolerance to low temperature stress.

  7. Ambient temperature enhanced acute cardiovascular-respiratory mortality effects of PM2.5 in Beijing, China

    Science.gov (United States)

    Li, Yi; Ma, Zhiqiang; Zheng, Canjun; Shang, Yu

    2015-12-01

    Studies have shown that temperature could modify the effect of ambient fine particles on mortality risk. In assessing air pollution effects, temperature is usually considered as a confounder. However, ambient temperature can alter people's physiological response to air pollution and might "modify" the impact of air pollution on health outcomes. This study investigated the interaction between daily PM2.5 and daily mean temperature in Beijing, China, using data for the period 2005-2009. Bivariate PM2.5-temperature response surfaces and temperature-stratified generalized additive model (GAM) were applied to study the effect of PM2.5 on cardiovascular, respiratory mortality, and total non-accidental mortality across different temperature levels. We found that low temperature could significantly enhance the effect of PM2.5 on cardiovascular mortality. For an increase of 10 μg/m3 in PM2.5 concentration in the lowest temperature range (-9.7˜2.6 °C), the relative risk (RR) of cardiovascular mortality increased 1.27 % (95 % CI 0.38˜2.17 %), which was higher than that of the whole temperature range (0.59 %, 95 % CI 0.22-1.16 %). The largest effect of PM2.5 on respiratory mortality appeared in the high temperature range. For an increase of 10 μg/m3 in PM2.5 concentration, RR of respiratory mortality increased 1.70 % (95 % CI 0.92˜3.33 %) in the highest level (23.50˜31.80 °C). For the total non-accidental mortality, significant associations appeared only in low temperature levels (-9.7˜2.6 °C): for an increase of 10 μg/m3 in current day PM2.5 concentration, RR increased 1.27 % (95 % CI 0.46˜2.00 %) in the lowest temperature level. No lag effect was observed. The results suggest that in air pollution mortality time series studies, the possibility of an interaction between air pollution and temperature should be considered.

  8. The potential effect of differential ambient and deployment chamber temperatures on PRC derived sampling rates with polyurethane foam (PUF) passive air samplers

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, Karen, E-mail: k.kennedy@uq.edu.a [University of Queensland, EnTox (National Research Centre for Environmental Toxicology), 39 Kessels Rd., Coopers Plains QLD 4108 (Australia); Hawker, Darryl W. [Griffith University, School of Environment, Nathan QLD 4111 (Australia); Bartkow, Michael E. [University of Queensland, EnTox (National Research Centre for Environmental Toxicology), 39 Kessels Rd., Coopers Plains QLD 4108 (Australia); Carter, Steve [Queensland Health Forensic and Scientific Services, Coopers Plains QLD 4108 (Australia); Ishikawa, Yukari; Mueller, Jochen F. [University of Queensland, EnTox (National Research Centre for Environmental Toxicology), 39 Kessels Rd., Coopers Plains QLD 4108 (Australia)

    2010-01-15

    Performance reference compound (PRC) derived sampling rates were determined for polyurethane foam (PUF) passive air samplers in both sub-tropical and temperate locations across Australia. These estimates were on average a factor of 2.7 times higher in summer than winter. The known effects of wind speed and temperature on mass transfer coefficients could not account for this observation. Sampling rates are often derived using ambient temperatures, not the actual temperatures within deployment chambers. If deployment chamber temperatures are in fact higher than ambient temperatures, estimated sampler-air partition coefficients would be greater than actual partition coefficients resulting in an overestimation of PRC derived sampling rates. Sampling rates determined under measured ambient temperatures and estimated deployment chamber temperatures in summer ranged from 7.1 to 10 m{sup 3} day{sup -1} and 2.2-6.8 m{sup 3} day{sup -1} respectively. These results suggest that potential differences between ambient and deployment chamber temperatures should be considered when deriving PRC-based sampling rates. - Internal deployment chamber temperatures rather than ambient temperatures may be required to accurately estimate PRC-based sampling rates.

  9. A complementary role for ELF3 and TFL1 in the regulation of flowering time by ambient temperature.

    Science.gov (United States)

    Strasser, Bárbara; Alvarez, Mariano J; Califano, Andrea; Cerdán, Pablo D

    2009-05-01

    Plants regulate their time to flowering by gathering information from the environment. Photoperiod and temperature are among the most important environmental variables. Sub-optimal, but not near-freezing, temperatures regulate flowering through the thermosensory pathway, which overlaps with the autonomous pathway. Here we show that ambient temperature regulates flowering by two genetically distinguishable pathways, one requiring TFL1 and another requiring ELF3. The delay in flowering time observed at lower temperatures was partially suppressed in single elf3 and tfl1 mutants, whereas double elf3 tfl1 mutants were insensitive to temperature. tfl1 mutations abolished the temperature response in cryptochrome mutants that are deficient in photoperiod perception, but not in phyB mutants, which have a constitutive photoperiodic response. In contrast to tfl1, elf3 mutations were able to suppress the temperature response in phyB mutants, but not in cryptochrome mutants. Gene expression profiles revealed that the tfl1 and elf3 effects are due to the activation of different sets of genes, and identified CCA1 and SOC1/AGL20 as being important cross-talk points. Finally, genome-wide gene expression analysis strongly suggests a general and complementary role for ELF3 and TFL1 in temperature signalling.

  10. Time series analysis of the association between ambient temperature and cerebrovascular morbidity in the elderly in Shanghai, China

    Science.gov (United States)

    Zhang, Xian-Jing; Ma, Wei-Ping; Zhao, Nai-Qing; Wang, Xi-Ling

    2016-01-01

    Research on the association between ambient temperature and cerebrovascular morbidity is scarce in China. In this study, we applied mixed generalized additive model (MGAM) to daily counts of cerebrovascular disease of Shanghai residents aged 65 years or older from 2007–2011, stratified by gender. Weighted daily mean temperature up to lags of one week was smoothed by natural cubic spline, and was added into the model to assess both linear and nonlinear effects of temperature. We found that when the mean temperature increased by 1 °C, the male cases of cerebrovascular disease reduced by 0.95% (95% Confidence Interval (CI): 0.80%, 1.10%) or reduced by 0.34% (95% CI: ‑0.68, 1.36%) in conditions of temperature was below or above 27 °C. However, for every 1 °C increase in temperature, the female cases of cerebrovascular disease increased by 0.34% (95% CI: ‑0.26%, 0.94%) or decreased by 0.92% (95% CI: 0.72, 1.11%) in conditions of temperature was below or above 8 °C, respectively. Temperature and cerebrovascular morbidity is negatively associated in Shanghai. MGAM is recommended in assessing the association between environmental hazards and health outcomes in time series studies.

  11. Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Abdelaziz, Omar [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shrestha, Som S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Munk, Jeffrey D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Linkous, Randall Lee [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Goetzler, William [Navigant Consulting Inc., Burlington, MA (United States); Guernsey, Matt [Navigant Consulting Inc., Burlington, MA (United States); Kassuga, Theo [Navigant Consulting Inc., Burlington, MA (United States)

    2015-10-01

    The Oak Ridge National Laboratory (ORNL) High-Ambient-Temperature Evaluation Program for low– global warming potential (Low-GWP) Refrigerants aims to develop an understanding of the performance of low-GWP alternative refrigerants to hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) refrigerants in mini-split air conditioners under high-ambient-temperature conditions. This final report describes the parties involved, the alternative refrigerant selection process, the test procedures, and the final results.

  12. Alternative Refrigerant Evaluation for High-Ambient Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners

    Energy Technology Data Exchange (ETDEWEB)

    Abdelaziz, Omar [ORNL; Munk, Jeffrey D [ORNL; Shrestha, Som S [ORNL; Linkous, Randall Lee [ORNL; Goetzler, William [Navigant Consulting Inc.; Guernsey, Matt [Navigant Consulting Inc.; Kassuga, Theo [Navigant Consulting Inc.

    2015-08-01

    The Oak Ridge National Laboratory (ORNL) High-Ambient Temperature Testing Program for Low-GWP Refrigerants aims to develop an understanding of the performance of low-Global Warming Potential (low-GWP) alternatives to Hydrochlorofluorocarbon (HCFC) and Hydrofluorocarbon (HFC) refrigerants in mini-split air conditioners under high ambient temperature conditions. This interim working paper describes the parties involved, the alternative refrigerants selection process, the test procedures, and the preliminary results.

  13. Tailpipe emissions from gasoline direct injection (GDI) and port fuel injection (PFI) vehicles at both low and high ambient temperatures.

    Science.gov (United States)

    Zhu, Rencheng; Hu, Jingnan; Bao, Xiaofeng; He, Liqiang; Lai, Yitu; Zu, Lei; Li, Yufei; Su, Sheng

    2016-09-01

    Vehicle emissions are greatly influenced by various factors that are related to engine technology and driving conditions. Only the fuel injection method and ambient temperature are investigated in this research. Regulated gaseous and particulate matter (PM) emissions from two advanced gasoline-fueled vehicles, one with direct fuel injection (GDI) and the other with port fuel injection (PFI), are tested with conventional gasoline and ethanol-blended gasoline (E10) at both -7 °C and 30 °C. The total particle number (PN) concentrations and size distributions are monitored with an Electrical Low Pressure Impactor (ELPI(+)). The solid PN concentrations are measured with a condensation particle counter (CPC) after removing volatile matters through the particle measurement program (PMP) system. The results indicate that decreasing the ambient temperature from 30 °C to -7 °C significantly increases the fuel consumption and all measured emissions except for NOx. The GDI vehicle exhibits lower fuel consumption than the PFI vehicle but emits more total hydrocarbons (THC), PM mass and solid PN emissions at 30 °C. The adaptability of GDI technology appears to be better than that of PFI technology at low ambient temperature. For example, the CO, THC and PM mass emission factors of the PFI vehicle are higher than those of the GDI vehicle and the solid PN emission factors are comparable in the cold-start tests at -7 °C. Specifically, during start-up the particulate matter emissions of the PFI are much higher than the GDI. In most cases, the geometric mean diameter (GMD) of the accumulation mode particles is 58-86 nm for both vehicles, and the GMD of the nucleation mode particles is 10-20 nm. The results suggest that the gaseous and particulate emissions from the PFI vehicle should not be neglected compared to those from the GDI vehicle especially in a cold environment.

  14. Design, Development and Implementation of the IR Signalling Techniques for Monitoring Ambient and Body Temperature in WBANs

    Directory of Open Access Journals (Sweden)

    Attiya Baqai

    2014-07-01

    Full Text Available Healthcare systems such as hospitals, homecare, telemedicine, and physical rehabilitation are expected to be revolutionized by WBAN (Wireless Body Area Networks. This research work aims to investigate, design, optimize, and demonstrate the applications of IR (Infra-Red communication systems in WBAN. It is aimed to establish a prototype WBAN system capable of measuring Ambient and Body Temperature using LM35 as temperature sensor and transmitting and receiving the data using optical signals. The corresponding technical challenges that have to be faced are also discussed in this paper. Investigations are carried out to efficiently design the hardware using low-cost and low power optical transceivers. The experimental results reveal the successful transmission and reception of Ambient and Body Temperatures over short ranges i.e. up to 3-4 meters. A simple IR transceiver with an LED (Light Emitting Diodes, TV remote control IC and Arduino microcontroller is designed to perform the transmission with sufficient accuracy and ease. Experiments are also performed to avoid interference from other sources like AC and TV remote control signals by implementing IR tags

  15. Simple Fabrication of Mesoporous Silica with Remarkable High Temperature Stability at Neutral pH and Ambient Conditions from TEOS

    Science.gov (United States)

    Hess, David; Vippagunta, Radha; Watkins, James

    2007-03-01

    Traditional silica synthesis processes can yield well ordered materials, but the synthesis conditions also lead to incomplete condensation of the silica network, which results in significant structural contraction upon calcination and limited thermal, hydrothermal and mechanical stability. Here we report the synthesis that, surprisingly, yields nearly complete condensation of the silica network (virtually all Q4 linkages) using cysteamine as the catalyst and polyoxyethylene surfactants as the structure directing agents in buffered solution at neutral pH and ambient temperature. Recently, small molecule bifunctional amines, including cysteamine, were evaluated by Morse and co-workers and found to produce silica from TEOS(JACS 2005, 127, 35). Our work combines the cysteamine catalyst system with structure-directing block copolymer surfactants at neutral pH and ambient temperature to produce mesoporous silica. The addition of tetraethyl orthosilicate (TEOS) to a solution of containing cysteamine, citrate buffer (pH 7.2) and 5wt Brij amphiphilic block copolymer (polyethylene oxide-polyethylene) yields mesoporous silica. The resulting mesoporous silica powder was analyzed using XRD, TGA, FTIR, TEM, and NMR. The materials were found to exhibit stability under extreme temperature calcinations (up to 800 C) in the presence of water. SAXS shows that 1.0 shrinkage upon calcination up to 800C. 29Si NMR analysis indicates a fully condensed silica network, Q4 linkages, in accordance with this observation.

  16. A study on the behaviour of TLD-100 glow peaks at extreme ambient temperatures in Riyadh, Saudi Arabia.

    Science.gov (United States)

    Al-Haj, Abdalla N; Lagarde, Charlie S

    2006-01-01

    In this study, the temperature-induced variations in the TLD-100 response and the modifications in its glow peaks are investigated in real environmental exposure conditions in Riyadh, Saudi Arabia, where ambient temperatures during summer reach >45 degrees C and with relative humidity of 8814 TLD cardholders were deployed as environmental dosemeters for a period of approximately 1 month for 12 consecutive months. One group was irradiated to 5 mGy 137Cs prior to deployment; another was irradiated to the same dose after deployment, while the last group was left unirradiated. Analysis of glow curves was done using commercially available glow curve deconvolution software (CGCD). Monthly variations in peak 3, 4 and 5 areas relative to the corresponding peak areas of a prompt glow curve are presented. Results of this study show good TL signal compensation between peaks 4 and 5 at all ambient temperatures encountered in this experiment, despite the observed individual variations experienced by each of these peaks. The sum of peak 4 and 5 areas is constant to within approximately 10%, for both pre- and post-irradiated dosemeters, during this 12-month cycle.

  17. Design and Application of Variable Temperature Setup for Scanning Electron Microscopy in Gases and Liquids at Ambient Conditions.

    Science.gov (United States)

    Al-Asadi, Ahmed S; Zhang, Jie; Li, Jianbo; Potyrailo, Radislav A; Kolmakov, Andrei

    2015-06-01

    Scanning electron microscopy (SEM) of nanoscale objects in dry and fully hydrated conditions at different temperatures is of critical importance in revealing details of their interactions with an ambient environment. Currently available WETSEM capsules are equipped with thin electron-transparent membranes and allow imaging of samples at atmospheric pressure, but do not provide temperature control over the sample. Here, we developed and tested a thermoelectric cooling/heating setup for WETSEM capsules to allow ambient pressure in situ SEM studies with a temperature range between -15 and 100°C in gaseous, liquid, and frozen conditions. The design of the setup also allows for correlation of the SEM with optical microscopy and spectroscopy. As a demonstration of the possibilities of the developed approach, we performed real-time in situ microscopy studies of water condensation on a surface of Morpho sulkowskyi butterfly wing scales. We observed that initial water nucleation takes place on top of the scale ridges. These results confirmed earlier discovery of a preexisting polarity gradient of the ridges of Morpho butterflies. Our developed thermoelectric cooling/heating setup for environmental capsules meets the diverse needs for in situ nanocharacterization in material science, catalysis, microelectronics, chemistry, and biology.

  18. Effects of ambient and preceding temperatures and metabolic genes on flight metabolism in the Glanville fritillary butterfly.

    Science.gov (United States)

    Wong, Swee Chong; Oksanen, Alma; Mattila, Anniina L K; Lehtonen, Rainer; Niitepõld, Kristjan; Hanski, Ilkka

    2016-02-01

    Flight is essential for foraging, mate searching and dispersal in many insects, but flight metabolism in ectotherms is strongly constrained by temperature. Thermal conditions vary greatly in natural populations and may hence restrict fitness-related activities. Working on the Glanville fritillary butterfly (Melitaea cinxia), we studied the effects of temperature experienced during the first 2 days of adult life on flight metabolism, genetic associations between flight metabolic rate and variation in candidate metabolic genes, and genotype-temperature interactions. The maximal flight performance was reduced by 17% by 2 days of low ambient temperature (15 °C) prior to the flight trial, mimicking conditions that butterflies commonly encounter in nature. A SNP in phosphoglucose isomerase (Pgi) had a significant association on flight metabolic rate in males and a SNP in triosephosphate isomerase (Tpi) was significantly associated with flight metabolic rate in females. In the Pgi SNP, AC heterozygotes had higher flight metabolic rate than AA homozygotes following low preceding temperature, but the trend was reversed following high preceding temperature, consistent with previous results on genotype-temperature interaction for this SNP. We suggest that these results on 2-day old butterflies reflect thermal effect on the maturation of flight muscles. These results highlight the consequences of variation in thermal conditions on the time scale of days, and they contribute to a better understanding of the complex dynamics of flight metabolism and flight-related activities under conditions that are relevant for natural populations living under variable thermal conditions.

  19. Twinning Behavior of a Basal Textured Commercially Pure Titanium Alloy TA2 at Ambient and Cryogenic Temperatures

    Institute of Scientific and Technical Information of China (English)

    Jin-ru LUO; Xiao SONG; Lin-zhong ZHUANG; Ji-shan ZHANG

    2016-01-01

    Twinning greatly affects the microstructure and mechanical performance of titanium alloys.The twinning behavior of a basal textured commercially pure titanium TA2 plates rolled to 4% reduction at the ambient and cryo-genic temperatures has been investigated.Microstructures of the rolled samples were investigated by optical micro-scope (OM)and the twinning analysis was carried out based on orientation data collected by electron back-scatter diffraction (EBSD).{1 122}contraction twins,{1 124}contraction twins and {1012}extension twins have been ob-served.Twinning mode activity varied with rolling temperature.Twinning is considered as the dominant deformation mechanism during rolling at both temperatures for the strain condition.Larger proportion of grains activates twin-ning during cryorolling,and greater number and more diverse types of twins are observed;manifestly related to the suppression of dislocation slips at the cryogenic temperature.{1 122 }contraction twins are the dominate twin type within samples rolled at both temperatures.Several {1 124}contraction twins are observed in the cryorolled sample while there are only a few in the sample rolled at room temperature.A few tiny {1012}twins have been identified in both samples.{1 124}contraction twins are preferentially activated at cryogenic deformation temperature and the{1012}extension twins may result in local strain accommodation.

  20. Hot-wire measurements with automatic compensation of ambient temperature changes

    Directory of Open Access Journals (Sweden)

    Miheev Nikolay I.

    2015-01-01

    Full Text Available A single sensor hot-wire device with automatic temperature compensation for velocity measurements is developed. Experience in measuring the velocity and temperature in a flow with variable temperature using self-made hot-wire equipment and probes is discussed. Results of the corresponding methodical experiments are presented.

  1. Hot-wire measurements with automatic compensation of ambient temperature changes

    OpenAIRE

    Miheev Nikolay I.; Molochnikov Valeriy M.; Kratirov Dmitriy V.; Hayrnasov Konstantin R.; Zanko Philipp S.

    2015-01-01

    A single sensor hot-wire device with automatic temperature compensation for velocity measurements is developed. Experience in measuring the velocity and temperature in a flow with variable temperature using self-made hot-wire equipment and probes is discussed. Results of the corresponding methodical experiments are presented.

  2. Coolant and ambient temperature control for chillerless liquid cooled data centers

    Energy Technology Data Exchange (ETDEWEB)

    Chainer, Timothy J.; David, Milnes P.; Iyengar, Madhusudan K.; Parida, Pritish R.; Simons, Robert E.

    2016-02-02

    Cooling control methods include measuring a temperature of air provided to a plurality of nodes by an air-to-liquid heat exchanger, measuring a temperature of at least one component of the plurality of nodes and finding a maximum component temperature across all such nodes, comparing the maximum component temperature to a first and second component threshold and comparing the air temperature to a first and second air threshold, and controlling a proportion of coolant flow and a coolant flow rate to the air-to-liquid heat exchanger and the plurality of nodes based on the comparisons.

  3. Performance evaluation of a two-phase anaerobic digestion process of synthetic domestic wastewater at ambient temperature.

    Science.gov (United States)

    Guerrero, L; Montalvo, S; Coronado, E; Chamy, R; Poirrier, P; Crutchik, D; Sánchez, E; De La Rubia, M A; Borja, R

    2009-06-01

    A two-phase anaerobic digestion process of synthetic domestic wastewater was studied at ambient temperature in mild to cold climates. The hydrolytic stage was carried out in a continuous stirred tank reactor with an effective volume of 1.2 L. The hydrolytic reactor operated at hydraulic retention times (HRTs) in the range of 1.3 to 2.7 h, which allowed for optimum HRT to be obtained in order to achieve a maximum amount of soluble COD. For the methanogenic stage, an up-flow anaerobic filter with a volume of 1.35 L and corrugated plastic rings as biomass immobilization support were used. During the investigation, the ambient temperature ranged between 21 degrees C and 24 degrees C. Synthetic domestic wastewater with a COD of 700 mg/L was used as substrate. The study was performed at total organic loading rates (OLR(T)) of 2.0-4.3 g COD/L. d, with a global HRT (including both hydrolytic and methanogenic stages) of 2.8-5.8 hours. A maximum percentage of organic matter removed of 88% was achieved at a global HRT of 5.8 hours. Under these operating conditions, the production of biogas was 97% higher than that obtained in the one-phase anaerobic digestion process. Additionally, the kinetics involved in the hydrolytic stage was determined using the Contois kinetic model, which adequately predicted the experimental results.

  4. Large scale synthesis and formation mechanism of silver nanoparticles in solid-state reactions at ambient temperature

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Aiqin, E-mail: zhangaiqin@zzuli.edu.cn [State Laboratory of Surface and Interface Science and Technology, Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, Zhengzhou 450002 (China); Tian, Yakun; Xiao, Yuanhua; Sun, Yuan [State Laboratory of Surface and Interface Science and Technology, Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, Zhengzhou 450002 (China); Li, Feng [State Laboratory of Surface and Interface Science and Technology, Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, Zhengzhou 450002 (China); American Advanced Nanotechnology, Houston, TX 77459 (United States)

    2015-07-15

    Highlights: • AgNPs were prepared by solid state reaction at ambient temperature. • Only silver nitrate and ascorbic acid were needed in this reaction. • The size of the AgNPs can be tuned conveniently. • Formation mechanism of the AgNPs was investigated. - Abstract: A one-step strategy for preparing Ag nanoparticles (AgNPs) on large scale is demonstrated successfully, based on solid-state reactions at ambient temperature. The environmentally friendly synthesis can be achieved by simply grinding AgNO{sub 3} and ascorbic acid (AA) for about 30 min without adding any solvent and organic protectors. The size of AgNPs can be readily controlled by adjusting the reaction parameters such as AgNO{sub 3}/AA molar ratio and reaction time. The nanostructures of AgNPs and their formation mechanism have been also investigated with XRD, FTIR, FESEM, HRTEM and HPLC–MS. It was found that AA can reduce Ag{sup +} into Ag{sup 0} to form AgNPs directly in accompanying with its first oxidation into 2,3-diketogulonic acid (2,3-DKG) and then a series of fragmentary species of 2,3-DKG.

  5. 绿橙常温保鲜的研究%Storage of Hainan Green Oranges at Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    陈婷; 王志国; 刘四新; 刘艳; 李从发

    2011-01-01

    The effects of different package methods, pre-storage methods, preservatives, and gibberellin on the storage of Hainan green oranges were studied at ambient temperature. The results showed that when they were washed using tap water, and soaked for lmin in the solution composed of 1000 mg/kg imazalil and 50 mg/kg gibberellin, and then packed by polyethylene film, Hainan green oranges could be stored for 28 d at ambient temperature (26~30%), with a good fruit rate of 93.3% and weight loss rate of 1.5% and green color in the pericarp.Prestorage and gibberellin were not good for the storage of Hainan green oranges.%本文主要研究包装方式,预贮、抑菌剂及赤霉素对海南绿橙常温下保鲜效果的影响,结果表明:抑霉唑1000mg/kg浸果1min,晾干后采用O.01mm厚的PE膜单果包装,常温(26~30℃)贮藏28d,好果率为93.3%,失重率为1.5%,果皮色泽青绿,果蒂新鲜,主要营养成分下降速度变缓;而预贮及赤霉素不适宜海南绿橙的采后处理.

  6. Analysis of multi-band pyrometry for emissivity and temperature measurements of gray surfaces at ambient temperature

    Science.gov (United States)

    Araújo, António

    2016-05-01

    A multi-band pyrometry model is developed to evaluate the potential of measuring temperature and emissivity of assumably gray target surfaces at 300 K. Twelve wavelength bands between 2 and 60 μm are selected to define the spectral characteristics of the pyrometers. The pyrometers are surrounded by an enclosure with known background temperature. Multi-band pyrometry modeling results in an overdetermined system of equations, in which the solution for temperature and emissivity is obtained through an optimization procedure that minimizes the sum of the squared residuals of each system equation. The Monte Carlo technique is applied to estimate the uncertainties of temperature and emissivity, resulting from the propagation of the uncertainties of the pyrometers. Maximum reduction in temperature uncertainty is obtained from dual-band to tri-band systems, a small reduction is obtained from tri-band to quad-band, with a negligible reduction above quad-band systems (a reduction between 6.5% and 12.9% is obtained from dual-band to quad-band systems). However, increasing the number of bands does not always reduce uncertainty, and uncertainty reduction depends on the specific band arrangement, indicating the importance of choosing the most appropriate multi-band spectral arrangement if uncertainty is to be reduced. A reduction in emissivity uncertainty is achieved when the number of spectral bands is increased (a reduction between 6.3% and 12.1% is obtained from dual-band to penta-band systems). Besides, emissivity uncertainty increases for pyrometers with high wavelength spectral arrangements. Temperature and emissivity uncertainties are strongly dependent on the difference between target and background temperatures: uncertainties are low when the background temperature is far from the target temperature, tending to very high values as the background temperature approaches the target temperature.

  7. Thermal behavior of human eye in relation with change in blood perfusion, porosity, evaporation and ambient temperature.

    Science.gov (United States)

    Rafiq, Aasma; Khanday, M A

    2016-12-01

    Extreme environmental and physiological conditions present challenges for thermal processes in body tissues including multi-layered human eye. A mathematical model has been formulated in this direction to study the thermal behavior of the human eye in relation with the change in blood perfusion, porosity, evaporation and environmental temperatures. In this study, a comprehensive thermal analysis has been performed on the multi-layered eye using Pennes' bio-heat equation with appropriate boundary and interface conditions. The variational finite element method and MATLAB software were used for the solution purpose and simulation of the results. The thermoregulatory effect due to blood perfusion rate, porosity, ambient temperature and evaporation at various regions of human eye was illustrated mathematically and graphically. The main applications of this model are associated with the medical sciences while performing laser therapy and other thermoregulatory investigation on human eye.

  8. Research Update: Direct conversion of h-BN into pure c-BN at ambient temperatures and pressures in air

    Directory of Open Access Journals (Sweden)

    Jagdish Narayan

    2016-02-01

    Full Text Available We report a direct conversion of hexagonal boron nitride (h-BN into pure cubic boron nitride (c-BN by nanosecond laser melting at ambient temperatures and atmospheric pressure in air. According to the phase diagram, the transformation from h-BN into c-BN can occur only at high temperatures and pressures, as the hBN-cBN-Liquid triple point is at 3500 K/9.5 GPa. Using nanosecond laser melting, we have created super undercooled state and shifted this triple point to as low as 2800 K and atmospheric pressure. The rapid quenching from super undercooled state leads to formation of super undercooled BN (Q-BN. The c-BN phase is nucleated from Q-BN depending upon the time allowed for nucleation and growth.

  9. Research Update: Direct conversion of h-BN into pure c-BN at ambient temperatures and pressures in air

    Energy Technology Data Exchange (ETDEWEB)

    Narayan, Jagdish, E-mail: narayan@ncsu.edu; Bhaumik, Anagh [Department of Materials Science and Engineering, Centennial Campus, North Carolina State University, Raleigh, North Carolina 27695-7907 (United States)

    2016-02-01

    We report a direct conversion of hexagonal boron nitride (h-BN) into pure cubic boron nitride (c-BN) by nanosecond laser melting at ambient temperatures and atmospheric pressure in air. According to the phase diagram, the transformation from h-BN into c-BN can occur only at high temperatures and pressures, as the hBN-cBN-Liquid triple point is at 3500 K/9.5 GPa. Using nanosecond laser melting, we have created super undercooled state and shifted this triple point to as low as 2800 K and atmospheric pressure. The rapid quenching from super undercooled state leads to formation of super undercooled BN (Q-BN). The c-BN phase is nucleated from Q-BN depending upon the time allowed for nucleation and growth.

  10. INFLUENCE OF COOLING RATE DURING QUENCHING ON IMPACT TOUGHNESS OF A HOT-WORK TOOL STEEL AT AMBIENT TEMPERATURE AND AT 200 °C

    Directory of Open Access Journals (Sweden)

    Henrik Jesperson

    2013-05-01

    Full Text Available Gross cracking of die-casting dies with inferior toughness sometimes occurs through too low preheating temperature and/or too slow cooling during quenching. This study aimed to clarify the influence of cooling rate on the toughness of the hot-work tool steel grade Uddeholm Vidar Superior at ambient temperature and at 200 °C, a typical preheating temperature for aluminium die-casting dies. Toughness was measured through instrumented Charpy V-notch impact testing. The decrease in energy absorption with increasing cooling time between 800°C and 500°C both at both ambient temperature and 200 °C was pronounced. At ambient temperature, the decrease in total energy was a consequence of a decrease in initiation energy whereas, at 200 °C, the decrease in total energy was due to a decrease in propagation energy.

  11. Model Study of the Influence of Ambient Temperature and Installation Types on Surface Temperature Measurement by Using a Fiber Bragg Grating Sensor.

    Science.gov (United States)

    Liu, Yi; Zhang, Jun

    2016-07-01

    Surface temperature is an important parameter in clinical diagnosis, equipment state control, and environmental monitoring fields. The Fiber Bragg Grating (FBG) temperature sensor possesses numerous significant advantages over conventional electrical sensors, thus it is an ideal choice to achieve high-accuracy surface temperature measurements. However, the effects of the ambient temperature and installation types on the measurement of surface temperature are often overlooked. A theoretical analysis is implemented and a thermal transfer model of a surface FBG sensor is established. The theoretical and simulated analysis shows that both substrate strain and the temperature difference between the fiber core and hot surface are the most important factors which affect measurement accuracy. A surface-type temperature standard setup is proposed to study the measurement error of the FBG temperature sensor. Experimental results show that there are two effects influencing measurement results. One is the "gradient effect". This results in a positive linear error with increasing surface temperature. Another is the "substrate effect". This results in a negative non-linear error with increasing surface temperature. The measurement error of the FBG sensor with single-ended fixation are determined by the gradient effect and is a linear error. It is not influenced by substrate expansion. Thus, it can be compensated easily. The measurement errors of the FBG sensor with double-ended fixation are determined by the two effects and the substrate effect is dominant. The measurement error change trend of the FBG sensor with fully-adhered fixation is similar to that with double-ended fixation. The adhesive layer can reduce the two effects and measurement error. The fully-adhered fixation has lower error, however, it is easily affected by substrate strain. Due to its linear error and strain-resistant characteristics, the single-ended fixation will play an important role in the FBG sensor

  12. Effects of temperature, algae biomass and ambient nutrient on the absorption of dissolved nitrogen and phosphate by Rhodophyte Gracilaria asiatica

    Science.gov (United States)

    Du, Rongbin; Liu, Liming; Wang, Aimin; Wang, Yongqiang

    2013-03-01

    Gracilaria asiatica, being highly efficient in nutrient absorption, is cultivated in sea cucumber ponds to remove nutrients such as nitrogen and phosphate. It was cultured in a laboratory simulating field conditions, and its nutrient absorption was measured to evaluate effects of environmental conditions. Ammonia nitrogen (AN), nitrate nitrogen (NN), total inorganic nitrogen (TIN), and soluble reactive phosphorus (SRP) uptake rate and removal efficiency were determined in a 4×2 factorial design experiment in water temperatures ( T) at 15°C and 25°C, algae biomass (AB) at 0.5 g/L and 1.0 g/L, total inorganic nitrogen (TIN) at 30 μmol/L and 60 μmol/L, and soluble reactive phosphorus (SRP) at 3 and 6 μmol/L. AB and ambient TIN or SRP levels significantly affected uptake rate and removal efficiency of AN, NN, TIN, and SRP ( P< 0.001). G. asiatica in AB of 0.5 g/L showed higher uptake rate and lower removal efficiency relative to that with AB of 1.0 g/L. Nitrogen and phosphorus uptake rate rose with increasing ambient nutrient concentrations; nutrient removal efficiency decreased at higher environmental nutrient concentrations. The algae preferred to absorb AN to NN. Uptake rates of AN, NN, and SRP were significantly affected by temperature ( P < 0.001); uptake rate was higher for the 25°C group than for the 15°C group at the initial experiment stage. Only the removal efficiency of AN and SRP showed a significant difference between the two temperature groups ( P< 0.01). The four factors had significant interactive effects on absorption of N and P, implying that G. asiatica has great bioremedial potential in sea cucumber culture ponds.

  13. Effects of temperature, algae biomass and ambient nutrient on the absorption of dissolved nitrogen and phosphate by Rhodophyte Gracilaria asiatica

    Institute of Scientific and Technical Information of China (English)

    DU Rongbin; LIU Liming; WANG Aimin; WANG Yongqiang

    2013-01-01

    Gracilaria asiatica,being highly efficient in nutrient absorption,is cultivated in sea cucumber ponds to remove nutrients such as nitrogen and phosphate.It was cultured in a laboratory simulating field conditions,and its nutrient absorption was measured to evaluate effects of environmental conditions.Ammonia nitrogen (AN),nitrate nitrogen (NN),total inorganic nitrogen (TIN),and soluble reactive phosphorus (SRP) uptake rate and removal efficiency were determined in a 4x2 factorial design experiment in water temperatures (T) at 15℃ and 25℃,algae biomass (AB) at 0.5 g/L and 1.0 g/L,total inorganic nitrogen (TIN) at 30 μmol/L and 60 μmol/L,and soluble reactive phosphorus (SRP) at 3 and 6 μmol/L.AB and ambient TIN or SRP levels significantly affected uptake rate and removal efficiency of AN,NN,TIN,and SRP (P<0.001).G.asiatica in AB of 0.5 g/L showed higher uptake rate and lower removal efficiency relative to that with AB of 1.0 g/L.Nitrogen and phosphorus uptake rate rose with increasing ambient nutrient concentrations; nutrient removal efficiency decreased at higher environmental nutrient concentrations.The algae preferred to absorb AN to NN.Uptake rates of AN,NN,and SRP were significantly affected by temperature (P<0.001); uptake rate was higher for the 25℃ group than for the 15℃ group at the initial experiment stage.Only the removal efficiency of AN and SRP showed a significant difference between the two temperature groups (P<0.01).The four factors had significant interactive effects on absorption of N and P,implying that G.asiatica has great bioremedial potential in sea cucumber culture ponds.

  14. Influence of ambient temperatures on metabolic responses of Murrah buffaloes of varying physiological states from arid tracts in India

    Directory of Open Access Journals (Sweden)

    Ashish Joshi

    2012-12-01

    Full Text Available Ambient temperature associated variations in metabolic responses of Murrah breed ofbuffaloes of varying physiological states belonging to arid tracts were investigated. Healthy adultfemale Murrah buffaloes were grouped according to physiological states into group A (non-pregnantmilch, pregnant milch and pregnant dry and group B (primipara and multipara and blood sampleswere collected during moderate, hot and cold environmental temperature periods to obtain sera.Metabolic responses were assessed by analyzing serum urea, creatinine, total proteins, cholesterol,triglycerides and glucose and the moderate mean values were 5.18±0.04 mmol L-1, 118.00±1.00 μmolL-1, 71.00±0.12 gL-1, 3.30±0.02 mmol L-1, 1.28±0.01 mmol L-1 and 3.7±0.02 mmol L-1, respectively.The mean values of serum urea and creatinine were significantly (p≤0.05 higher during hot and coldambiences, the mean value of total serum proteins and triglycerides were significantly (p≤0.05 lowerduring hot and cold ambiences and the mean values of cholesterol and glucose were significantly(p≤0.05 lower during hot ambience and significantly (p≤0.05 higher during cold ambience ascompared to respective moderate mean value. The mean values of non pregnant milch, pregnant milchand pregnant dry animals differed significantly (p≤0.05 from each other in all the environmentalperiods. It was concluded that extreme hot and cold ambient temperatures affected the buffaloes ofall physiological states which was evident in the form of variations in the metabolic responses tocombat the environmental challenges.

  15. Physical exercise-induced changes in the core body temperature of mice depend more on ambient temperature than on exercise protocol or intensity

    Science.gov (United States)

    Wanner, Samuel Penna; Costa, Kátia Anunciação; Soares, Anne Danieli Nascimento; Cardoso, Valbert Nascimento; Coimbra, Cândido Celso

    2014-08-01

    The mechanisms underlying physical exercise-induced hyperthermia may be species specific. Therefore, the present study aimed to investigate the effects of exercise intensity and ambient temperature on the core body temperature ( T core) of running mice, which provide an important experimental model for advancing the understanding of thermal physiology. We evaluated the influence of different protocols (constant- or incremental-speed exercises), treadmill speeds and ambient temperatures ( T a) on the magnitude of exercise-induced hyperthermia. To measure T core, a telemetric sensor was implanted in the abdominal cavity of male adult Swiss mice under anesthesia. After recovering from the surgery, the animals were familiarized to running on a treadmill and then subjected to the different running protocols and speeds at two T a: 24 °C or 34 °C. All of the experimental trials resulted in marked increases in T core. As expected, the higher-temperature environment increased the magnitude of running-induced hyperthermia. For example, during incremental exercise at 34 °C, the maximal T core achieved was increased by 1.2 °C relative to the value reached at 24 °C. However, at the same T a, neither treadmill speed nor exercise protocol altered the magnitude of exercise-induced hyperthermia. We conclude that T core of running mice is influenced greatly by T a, but not by the exercise protocols or intensities examined in the present report. These findings suggest that the magnitude of hyperthermia in running mice may be regulated centrally, independently of exercise intensity.

  16. Epitaxial growth of MgB2 films at ambient temperature

    Science.gov (United States)

    Shishido, Hiroaki; Yoshida, Takuya; Nakagami, Takatoshi; Ishida, Takekazu

    We grew crystalline MgB2 thin films using molecular beam epitaxy at a low substrate temperature of 110 °C under an ultrahigh vacuum of about 10-6 Pa. MgB2 thin films were deposited on the (001) surface of a 4H-SiC substrate with an epitaxial Mg buffer layer. The epitaxial growth was confirmed by X-ray diffraction measurements. MgB2 thin films show a sharp superconducting transition at 27.2 K, with a relatively narrow superconducting transition width ΔTc = 0.9 K. The growth temperature was lower than any in prior reports on superconducting MgB2 thin films. The presence of the epitaxial Mg buffer layer is crucial for reducing the epitaxial temperature.

  17. Study on Desulfurization Efficiency and Products of Ce-Doped Nanosized ZnO Desulfurizer at Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    Li Fen; Yan Bo; Zhang Jie; Jiang Anxi; Shao Chunhong; Kong Xiangji; Wang Xin

    2007-01-01

    Ce-doped nanosized ZnO desulfurizer was prepared by homogeneous precipitation, and its desulfurization efficiency at ambient temperature was investigated through dynamic experiments. The results showed that the desulfurization activity of nanosized Ce-ZnO had improved greatly, compared to nanosized ZnO desulfurizer. Nanosized Ce-ZnO desulfurizer was characterized by XRD, TPD-MS, XPS, and TEM. The research results indicated that doping Ce decreased the particle size of the nanosized ZnO desulfurizer and ZnS was the principal desulfurization product. There were adsorption complexes of HS and S on the surface of desulfurizer as well. Only a small amount of vapor appeared in the tail gas on the condition of meeting the precision of desulfurization.

  18. Facile palladium catalyzed Suzuki-Miyaura coupling in air and water at ambient temperature

    KAUST Repository

    Marziale, Alexander N.

    2010-01-01

    A new palladacyclic catalyst yields high activities in aqueous Suzuki-Miyaura coupling at room temperature. Using an optimized protocol, a broad range of products can be isolated in good to excellent yields and high purity by simple filtration. © 2010 The Royal Society of Chemistry.

  19. Predator-released compounds, ambient temperature and competitive exclusion among differently sized Daphnia species

    NARCIS (Netherlands)

    Vijverberg, J.; Vos, Matthijs

    2006-01-01

    1. We studied the effects of fish water and temperature on mechanisms of competitive exclusion among two Daphnia species in flow-through microcosms. The large-bodied D. pulicaria outcompeted the medium sized D. galeata × hyalina in fish water, but not in the control treatment. Daphnia galeata × hyal

  20. Fundamental Studies on Ambient Temperature Creep Deformation Behavior of Alpha and Alpha-Beta Titanium Alloys

    Science.gov (United States)

    2013-01-31

    Electron Microscope Elemental tin t time T Ta temperature Elemental Tantalum TEM Ti Transmission Electron Microscope Elemental titanium Ti...7 [45] and 8 [46]. The chemical compositions are actual chemical compositions of the alloys after fabrication as determined by the wet chemistry

  1. Impacts of Ambient Temperature and Pressure on PM2.5 Emission Profiles of Light-Duty Diesel Vehicles

    Science.gov (United States)

    Wang, Chenyu; Wu, Ye; Li, Zhenhua; Hao, Jiming

    2012-01-01

    The impact of the environmental factors on the emissions of particulate matter (PM) number, size distribution and mass size distribution from diesel passenger cars was evaluated. Particle measurements from five modern light-duty diesel vehicles (LDDV) were performed in June and November 2011. Commercial low sulfur diesel fuel (less than 50 ppm) was used during the testing of these vehicles which were not equipped with after-treatment devices. The dynamometer test was based on the Economic Commission of Europe (ECE) 15 cycles. The results indicate that PM2.5 emissions from LDDV are significantly affected by ambient temperature and pressure. A comparison of the emissions concentration of PM2.5 in these two different months showed that the number concentration in June was (3.8 ± 0.69) × 107 cm-3 and (2.5 ± 0.66) × 107 cm-3 in November. The PM concentration of about 30 nm diameter was 25 ± 6% of the total emissions in November while only 14 ± 3% of total emissions in June. In the 60 nm to 2.5 μm test range, November data shows less of a contribution for number than data from June testing. The concentration of mass emissions in June was (325 ± 44) mg/m3 and (92 ± 30) mg/m3 in November. The contribution of the number of PM particles in November testing is lower than testing in June by 34% and the mass concentration in November is 70% lower than that in June. With the decrease of ambient temperature and the increase of ambient pressure, both the oxygen concentration in cylinder and air-fuel ratio are increased, which caused lower particle number and mass emissions during November testing. The size distribution is also altered by these changes: the more efficient in-cylinder combustion resulted in a higher proportion of particles in the 30 nm and smaller range than for other particle sizes.

  2. Rechargeable lithium battery employing a new ambient temperature hybrid polymer electrolyte based on PVK+PVdF-HFP (copolymer)

    Science.gov (United States)

    Michael, M. S.; Prabaharan, S. R. S.

    We describe here for the first time, our recent success in developing an ambient temperature Li + conducting solid polymer electrolyte (SPE) using the concept of polymer alloying upon blending two thermoplastic polymers such as poly(vinylidene) fluoride-hexafluoropropylene (PVdF-HFP-copolymer) and poly( N-vinylcarbazole), PVK and achieved the room temperature electrolytic conductivity ( σi) of 0.7×10 -3 S/cm for a typical composition of PVdF-HFP copolymer/PVK blend mixed with EC/LiBF 4 molar composition. The ionic transference number of 0.49 was deduced from combined ac-impedance and dc polarization method. High-resolution optical microscopic examination revealed the disappearance of characteristic highly porous surface structure of PVdF-HFP matrix upon blending with PVK leading to the formation of resultant PVdF-HFP/PVK blend polymer alloy. The electrochemical stability of the polymer electrolyte membrane thus obtained was found to be stable up to ˜4.7 V versus Li/Li +. The new hybrid alloy polymer electrolyte membrane was found to exhibit good interfacial properties against lithium metal and thus, it was found to aid the room temperature operation as electrolytic membrane cum separator in all-solid state rechargeable lithium polymer test cell, LiCo 0.8Ni 0.2O 2/SPE/Li.

  3. A high-temperature, ambient-pressure ultra-dry operando reactor cell for Fourier-transform infrared spectroscopy

    Science.gov (United States)

    Köck, Eva-Maria; Kogler, Michaela; Pramsoler, Reinhold; Klötzer, Bernhard; Penner, Simon

    2014-08-01

    The construction of a newly designed high-temperature, high-pressure FT-IR reaction cell for ultra-dry in situ and operando operation is reported. The reaction cell itself as well as the sample holder is fully made of quartz glass, with no hot metal or ceramic parts in the vicinity of the high-temperature zone. Special emphasis was put on chemically absolute water-free and inert experimental conditions, which includes reaction cell and gas-feeding lines. Operation and spectroscopy up to 1273 K is possible, as well as pressures up to ambient conditions. The reaction cell exhibits a very easy and variable construction and can be adjusted to any available FT-IR spectrometer. Its particular strength lies in its possibility to access and study samples under very demanding experimental conditions. This includes studies at very high temperatures, e.g., for solid-oxide fuel cell research or studies where the water content of the reaction mixtures must be exactly adjusted. The latter includes all adsorption studies on oxide surfaces, where the hydroxylation degree is of paramount importance. The capability of the reaction cell will be demonstrated for two selected examples where information and in due course a correlation to other methods can only be achieved using the presented setup.

  4. Characterization of membrane foulants at ambient temperature anaerobic membrane bioreactor treating low-strength industrial wastewater

    DEFF Research Database (Denmark)

    Zarebska, Agata; Kjerstadius, Hamse; Petrinic, Irena

    2016-01-01

    with anaerobic biological treatment at low temperature could not only reduce the operational cost of AD, but also alleviate environmental problems. However, at low temperature the AnMBR may suffer more fouling due to the increased extracellular polymeric substances production excreted by bacteria hampering......The large volume of industrial low-strength wastewaters has a potential for biogas production through conventional anaerobic digestion (AD), limited though by the need of heating and concentrating of the wastewaters. The use of anaerobic membrane bioreactor (AnMBR) combining membrane filtration...... the application of the process for the industrial wastewater treatment. In order to solve or reduce the fouling problem it is necessary to have a good insight into the processes that take place both on and in the membrane pores during filtration. Therefore, the objective of this study is to contribute to a better...

  5. Heterogeneous Palladium Chloride Catalyzed Ligand-free Suzuki-Miyaura Coupling Reactions at Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    WANG Min; WANG Lei

    2008-01-01

    A mild and efficient ligand-free Suzuki-Miyaura coupling reaction catalyzed by heterogeneous palladium chloride was developed at room temperature in a short reaction time under air atmosphere.Various phenyl iodides,bromides and activated chlorides were coupled with sodium tetraphenylborate or phenylboronic acids efficiently to afford the corresponding cross-coupled products in good to excellent yields.Furthermore,the catalyst could be recycled up to four times without loss of its activity.

  6. Ambient organic carbon to elemental carbon ratios: Influence of the thermal–optical temperature protocol and implications

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Yuan, E-mail: ycheng@mail.tsinghua.edu.cn [State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing (China); He, Ke-bin, E-mail: hekb@tsinghua.edu.cn [State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing (China); State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing (China); Duan, Feng-kui; Du, Zhen-yu [State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing (China); Zheng, Mei [College of Environmental Sciences and Engineering, Peking University, Beijing (China); Ma, Yong-liang [State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing (China)

    2014-01-01

    Ambient organic carbon (OC) to elemental carbon (EC) ratios are strongly associated with not only the radiative forcing due to aerosols but also the extent of secondary organic aerosol (SOA) formation. An inter-comparison study was conducted based on fine particulate matter samples collected during summer in Beijing to investigate the influence of the thermal–optical temperature protocol on the OC to EC ratio. Five temperature protocols were used such that the NIOSH (National Institute for Occupational Safety and Health) and EUSAAR (European Supersites for Atmospheric Aerosol Research) protocols were run by the Sunset carbon analyzer while the IMPROVE (the Interagency Monitoring of Protected Visual Environments network)-A protocol and two alternative protocols designed based on NIOSH and EUSAAR were run by the DRI analyzer. The optical attenuation measured by the Sunset carbon analyzer was more easily biased by the shadowing effect, whereas total carbon agreed well between the Sunset and DRI analyzers. The EC{sub IMPROVE-A} (EC measured by the IMPROVE-A protocol; similar hereinafter) to EC{sub NIOSH} ratio and the EC{sub IMPROVE-A} to EC{sub EUSAAR} ratio averaged 1.36 ± 0.21 and 0.91 ± 0.10, respectively, both of which exhibited little dependence on the biomass burning contribution. Though the temperature protocol had substantial influence on the OC to EC ratio, the contributions of secondary organic carbon (SOC) to OC, which were predicted by the EC-tracer method, did not differ significantly among the five protocols. Moreover, the SOC contributions obtained in this study were comparable with previous results based on field observation (typically between 45 and 65%), but were substantially higher than the estimation provided by an air quality model (only 18%). The comparison of SOC and WSOC suggests that when using the transmittance charring correction, all of the three common protocols (i.e., IMPROVE-A, NIOSH and EUSAAR) could be reliable for the estimation

  7. Dynamic instability at the origin of oxygen ion conduction in solid oxides at ambient temperature

    Indian Academy of Sciences (India)

    Helmut Schober; Werner Paulus; Tanguy Berthier; Olivier Hernandez; Monica Ceretti; Stefan Eibl; Mark Johnson; Marie Plazanet; Carlo Lamberti

    2008-11-01

    The conduction of ions in solids is of paramount importance for many technological devices like solid oxide fuel cells. It is inherent to solids that ions are trapped within potential wells. Their transport thus has to be activated at the price of elevated temperatures, a condition that is often incompatible with technological applications. While atomic vibrations have the potential of assisting the diffusion process, little is known about the exact conditions that have to be reunited to trigger such a process. Here we show that dynamic instability is responsible for the large ion conduction in SrFeO2.5 with brownmillerite-type structure. Using ab-initio molecular dynamics calculations we observe the migration of oxygen ions away from the original lattice positions into the vacancy channels of the brownmillerite structure. The escape of the oxygen ion is rendered possible by the destabilization of a shallow potential well due to low-lying vibrational modes, the existence of which is confirmed by neutron spectroscopy. Analysing the lattice dynamics as a function of structural parameters it is possible to identify the structural subtleties responsible for the instability. It is found that in the isostructural compound CaFeO2.5, fast oxygen ion diffusion is absent at low temperatures. The origin of this behaviour lies with the slightly different iron–oxygen distances rendering the potentials better defined and less amenable to dynamical destabilization. The here-introduced concept of dynamical instability is not restricted to the discussed class of materials but may be applied to any system that features ion conduction at low temperatures.

  8. An Ambient Temperature Molten Sodium-Vanadium Battery with Aqueous Flowing Catholyte.

    Science.gov (United States)

    Liu, Caihong; Shamie, Jack S; Shaw, Leon L; Sprenkle, Vincent L

    2016-01-20

    In this study, we have investigated the key factors dictating the cyclic performance of a new type of hybrid sodium-based flow batteries (HNFBs) that can operate at room temperature with high cell voltages (>3 V), multiple electron transfer redox reactions per active ion, and decoupled design of power and energy. HNFBs are composed of a molten Na-Cs alloy anode, flowing aqueous catholyte, and a Na-β″-Al2O3 solid electrolyte as the separator. The surface functionalization of graphite felt electrodes for the flowing aqueous catholyte has been studied for its effectiveness in enhancing V(2+)/V(3+), V(3+)/V(4+), and V(4+)/V(5+) redox couples. The V(4+)/V(5+) redox reaction has been further investigated at different cell operation temperatures for its cyclic stability and how the properties of the solid electrolyte membrane play a role in cycling. These fundamental understandings provide guidelines for improving the cyclic performance and stability of HNFBs with aqueous catholytes. We show that the HNFB with aqueous V-ion catholyte can reach high storage capacity (∼70% of the theoretical capacity) with good Coulombic efficiency (90% ± 1% in 2-30 cycles) and cyclic performance (>99% capacity retention for 30 cycles). It demonstrates, for the first time, the potential of high capacity HNFBs with aqueous catholytes, good capacity retention and long cycling life. This is also the first demonstration that Na-β″-Al2O3 solid electrolyte can be used with aqueous electrolyte at near room temperature for more than 30 cycles.

  9. The Effect of Ambient Temperature and Exercise to the Level of Exhaustion on

    Directory of Open Access Journals (Sweden)

    Somaye Kasharafifard

    2014-06-01

    Full Text Available Background: The increase in the amount of heat shock protein and C-reactive protein occurring as a result of stress was done with the aims of returning cell homeostasis, successful restoration of cell injury and protection of cell against more injuries. Materials and Methods: Fifteen climber and 15 non athlete subjects were chosen. A selected aerobic test was done by the subjects using Monark bicycle under two different conditions. Before starting the test, the subjects were exposed to a normal condition with the temperature of 24±2°C for an hour and a blood sample was taken from all the subjects. Then immediately, the subjects took the selected aerobic test to the level of exhaustion and blood sample was taken again. A week later, these subjects were exposed to a heated environment with the temperature of 38±2°C, followed by blood sample taking. Finally, the test was done by the subjects to the level of exhaustion and the last blood sample was taken. Then, the amount of heat shock protein (HSP and C - reactive protein (CRP in blood samples was measured. Results: A meaningful difference was observed in the changes of heat shock proteins (p=0.012 and C-reactive protein (p=0.02 between athlete and non athlete subjects. There was no meaningful difference in CRP and HSP in normal and hot condition for non athlete subjects before and after the test. But the result of the study demonstrates that There was a meaningful difference for athletes in both conditions before and after the test (p=0.002. Conclusion: Based on the study, it is claimed that while an athlete is exposed to several stressful conditions (e.g. high temperature and physical exercise, compared to a non athlete, the reaction of his body cells is more significant in order to prevent the injury.

  10. Evaluation and Response of Aged Flexible Airfield Pavements at Ambient Temperatures Using the Falling Weight Deflectometer

    Science.gov (United States)

    1988-01-01

    3) accessibilty to the airfield, especially during the day, was virtually unlimited, 4) the entire airfield, excluding parking aprons, was comprised...role. 135 LU C4 Cy! C CU 0 C*4O LU - CC-) 0 - AUla j? cc IL 0 01 tn in P4 4 Lui ( tn to4- .~0 N U LLL 0m Sr CHAPTER 6 ANALYSES OF FIELD MEASURED FWD...tempera- tures were virtually the same for both sites. This showed that as the degree of cracking in the asphalt concrete diminished, temperature

  11. Effect of surrogate aggregates on the thermal conductivity of concrete at ambient and elevated temperatures.

    Science.gov (United States)

    Yun, Tae Sup; Jeong, Yeon Jong; Youm, Kwang-Soo

    2014-01-01

    The accurate assessment of the thermal conductivity of concretes is an important part of building design in terms of thermal efficiency and thermal performance of materials at various temperatures. We present an experimental assessment of the thermal conductivity of five thermally insulated concrete specimens made using lightweight aggregates and glass bubbles in place of normal aggregates. Four different measurement methods are used to assess the reliability of the thermal data and to evaluate the effects of the various sensor types. The concrete specimens are also assessed at every 100 °C during heating to ~800 °C. Normal concrete is shown to have a thermal conductivity of ~2.25 W m(-1) K(-1). The surrogate aggregates effectively reduce the conductivity to ~1.25 W m(-1) K(-1) at room temperature. The aggregate size is shown not to affect thermal conduction: fine and coarse aggregates each lead to similar results. Surface contact methods of assessment tend to underestimate thermal conductivity, presumably owing to high thermal resistance between the transducers and the specimens. Thermogravimetric analysis shows that the stages of mass loss of the cement paste correspond to the evolution of thermal conductivity upon heating.

  12. Seasonality, ambient temperatures and hospitalizations for acute exacerbation of COPD: a population-based study in a metropolitan area

    Directory of Open Access Journals (Sweden)

    Almagro P

    2015-05-01

    Full Text Available Pere Almagro,1 Carme Hernandez,2,3,7 Pable Martinez-Cambor,4,5 Ricard Tresserras,2,6 Joan Escarrabill2,7 1Acute Geriatric Care Unit, Internal Medicine, University Hospital Mútua de Terrasa, University of Barcelona, Barcelona, Spain; 2Respiratory Disease Management Plan, Department of Health of the Autonomous Government of Catalonia, Observatory of Respiratory Therapy, 3Integrated Care Unit, Medical and Nursing Management, Hospital Clínic Barcelona, Barcelona, 4Oficina de Investigación Biosanitaria de Oviedo, Asturias, Spain; 5Universidad Autonoma de Chile, Santiago, Chile; 6Health Department, 7Chronic Diseases Care Program, Hospital Clinic, Hospital Clínic & REDISSEC (Health Services Research on Chronic Patients Network, Barcelona, Spain Background: Excluding the tropics, exacerbations of chronic obstructive pulmonary disease (COPD are more frequent in winter. However, studies that directly relate hospitalizations for exacerbation of COPD to ambient temperature are lacking. The aim of this study was to assess the influence of temperature on the number of hospitalizations for COPD.Methods: This was a population-based study in a metropolitan area. All hospital discharges for acute exacerbation of COPD during 2009 in Barcelona and its metropolitan area were analyzed. The relationship between the number of hospitalizations for COPD and the mean, minimum, and maximum temperatures alongside comorbidity, humidity, influenza rate, and environmental pollution were studied.Results: A total of 9,804 hospitalization discharges coded with COPD exacerbation as a primary diagnosis were included; 75.4% of cases were male with a mean age of 74.9±10.5 years and an average length of stay of 6.5±6.1 days. The highest number of admissions (3,644 [37.2%] occurred during winter, followed by autumn with 2,367 (24.1%, spring with 2,347 (23.9%, and summer with 1,446 (14.7%; P<0.001. The maximum, minimum, and mean temperatures were associated similarly with the

  13. Biogenic Synthesis of Fluorescent Carbon Dots at Ambient Temperature Using Azadirachta indica (Neem) gum.

    Science.gov (United States)

    Phadke, Chinmay; Mewada, Ashmi; Dharmatti, Roopa; Thakur, Mukeshchand; Pandey, Sunil; Sharon, Madhuri

    2015-07-01

    Synthesis of fluorescent Carbon Dots (CDs) from various carbonaceous materials apparently has acquired lots of interest amongst researchers as the corollary of the properties of CDs; which are subsequently getting unveiled. In this study we report the use of Azadirachta indica (Neem) Gum as a novel natural pre-cursor for synthesis of CDs at room temperature. Water soluble CDs of around 5-8 nm were obtained after treatment of the gum with ethanol and NaOH. These CDs exhibited green fluorescence in UV-light (λ = 365 nm). These CDs were found to be stable, having many bio-linkers attached on their surface, making it suitable for drug attachment and hence can serve as potential candidates for applications like drug delivery vehicles as well as for biosensors.

  14. Rod-Shaped Magnetite Nano/Microparticles Synthesis at Ambient Temperature

    Directory of Open Access Journals (Sweden)

    Balaprasad Ankamwar

    2013-01-01

    Full Text Available Here, we reported room temperature synthesis of Fe3O4 rod-shaped nano/microparticles by chemical reduction method from FeCl3 precursor and NaBH4 as the reducing agent in the presence of the pyrrole as a capping agent. The magnetic Fe3O4 particles were characterized by several methods, such as SEM, XRD, FTIR, and TGA. The average aspect ratio of Fe3O4 rod-shaped particles was ~2.8. These particles were redispersed in deionised water to form a colloidal solution and showed magnetic properties. This economical synthesis route is scalable, and Fe3O4 particles can be exploited for various applications such as MRI contrast enhancement, biodiseperations, Ni-Fe batteries, and as a catalyst.

  15. Surface-initiated atom transfer radical polymerization of methyl methacrylate from magnetite nanoparticles at ambient temperature.

    Science.gov (United States)

    Raghuraman, G K; Dhamodharan, R

    2006-07-01

    The synthesis of methyl methacrylate (MMA) brush from the surface of magnetite nanoparticles (core-shell structure), from initiator moieties anchored covalently to the nanoparticles, via room temperature atom transfer radical polymerization (ATRP) is described. The surface-initiated polymerization was carried out from a surface-confined initiator containing a 2-bromoisobutyrate moiety with Cu(I)Br/PMDETA catalytic system. The initiator moiety was covalently anchored to the nanoparticles via a two step modification reaction scheme. Controlled polymerization was observed if ethyl-2-bromoisobutyrate (2-EiBrB) was added as a free/sacrificial initiator. A linear increase of molecular weight and a narrow molecular weight distribution of the PMMA formed in solution, provide evidence for a controlled surface-initiated polymerization, leading to surface-attached polymer brushes under mild conditions. The grafted PMMA provides good stability and dispersibility for the nanoparticles in organic solvents.

  16. Ambient temperature desulfurizer of nano-ZnO modified with cerium

    Institute of Scientific and Technical Information of China (English)

    LI Fen; YAN Bo; ZHANG Jie; JIANG An-xi; SHAO Chun-hong; ZHANG Yan-ping

    2008-01-01

    The compound nano-ZnO modified with Ce was prepared by homogeneous precipitation. IR, XRD and dynamic experiments show that the crystal size of nano-ZnO desulfurizer is decreased after being modified with Ce and its desulfurization activities are improved greatly. When calcined at 270 ℃, Ce distributes evenly calcining temperature is 570℃, the crystal CeO2separates out and the amorphous structure of zinc oxide disap-pears, at the same time, the crystal is perfect and its size increases, but the desulfurization activities decrease. The desulfurization product of nano-ZnO modified with Ce was analyzed with XPS. The results show that the ad-sorption compound of HS, S and ZnS exists on the surface of the desulfurizer.

  17. Station for spatially distributed measurements of soil moisture and ambient temperature

    Science.gov (United States)

    Jankovec, Jakub; Šanda, Martin; Haase, Tomáš; Sněhota, Michal; Wild, Jan

    2013-04-01

    Third generation of combined thermal and soil moisture standalone field station coded TMS3 with wireless communication is presented. The device combines three thermometers (MAXIM/DALLAS Semiconductor DS7505U with -55 to +125°C range and 0.0625°C resolution, 0.5°C precision in 0 to +70°C range and 2°C precision out of this range). Soil moisture measurement is performed based on time domain transmission (TDT) principle for the full range of soil moisture with 0.025% resolution within the full possible soil moisture span for the most typical conditions of dry to saturated soils with safe margins to enable measurements in freezing, hot or saline soils. Principal compact version is designed for temperature measurements approximately at heights -10, 0 and +15 cm relative to soil surface when installed vertically and soil moisture measurements between 0 and 12 cm below surface. Set of buriable/subsurface stations each with 2.2 meter extension cord with soil and surface temperature measurement provides possibility to scan vertical soil profile for soil moisture and temperature at desired depths. USB equipped station is designed for streamed direct data acquisition in laboratory use in 1s interval. Station is also equipped with the shock sensor indicating the manipulation. Presented version incorporates life time permanent data storage (0.5 million logs). Current sensor design aims towards improved durability in harsh outdoor environment with reliable functioning in wet conditions withstanding mechanical or electric shock destruction. Insertion into the soil is possible by pressing with the use of a simple plastic cover. Data are retrieved by contact portable pocket collector (second generation) or by RFID wireless communication for hundreds meter distance (third generation) in either star pattern of GSM hub to stations or lined up GSM to station to another station both in comprised data packets. This option will allow online data harvesting and real time process

  18. Effect of season and high ambient temperature on activity levels and patterns of grizzly bears (Ursus arctos.

    Directory of Open Access Journals (Sweden)

    Michelle L McLellan

    Full Text Available Understanding factors that influence daily and annual activity patterns of a species provides insights to challenges facing individuals, particularly when climate shifts, and thus is important in conservation. Using GPS collars with dual-axis motion sensors that recorded the number of switches every 5 minutes we tested the hypotheses: 1. Grizzly bears (Ursus arctos increase daily activity levels and active bout lengths when they forage on berries, the major high-energy food in this ecosystem, and 2. Grizzly bears become less active and more nocturnal when ambient temperature exceeds 20°C. We found support for hypothesis 1 with both male and female bears being active from 0.7 to 2.8 h longer in the berry season than in other seasons. Our prediction under hypothesis 2 was not supported. When bears foraged on berries on a dry, open mountainside, there was no relationship between daily maximum temperature (which varied from 20.4 to 40.1°C and the total amount of time bears were active, and no difference in activity levels during day or night between warm (20.4-27.3°C and hot (27.9-40.1°C days. Our results highlight the strong influence that food acquisition has on activity levels and patterns of grizzly bears and is a challenge to the heat dissipation limitation theory.

  19. Effect of season and high ambient temperature on activity levels and patterns of grizzly bears (Ursus arctos).

    Science.gov (United States)

    McLellan, Michelle L; McLellan, Bruce N

    2015-01-01

    Understanding factors that influence daily and annual activity patterns of a species provides insights to challenges facing individuals, particularly when climate shifts, and thus is important in conservation. Using GPS collars with dual-axis motion sensors that recorded the number of switches every 5 minutes we tested the hypotheses: 1. Grizzly bears (Ursus arctos) increase daily activity levels and active bout lengths when they forage on berries, the major high-energy food in this ecosystem, and 2. Grizzly bears become less active and more nocturnal when ambient temperature exceeds 20°C. We found support for hypothesis 1 with both male and female bears being active from 0.7 to 2.8 h longer in the berry season than in other seasons. Our prediction under hypothesis 2 was not supported. When bears foraged on berries on a dry, open mountainside, there was no relationship between daily maximum temperature (which varied from 20.4 to 40.1°C) and the total amount of time bears were active, and no difference in activity levels during day or night between warm (20.4-27.3°C) and hot (27.9-40.1°C) days. Our results highlight the strong influence that food acquisition has on activity levels and patterns of grizzly bears and is a challenge to the heat dissipation limitation theory.

  20. Effects of ambient air temperature, humidity and rainfall on annual survival of adult little penguins Eudyptula minor in southeastern Australia

    Science.gov (United States)

    Ganendran, L. B.; Sidhu, L. A.; Catchpole, E. A.; Chambers, L. E.; Dann, P.

    2016-08-01

    Seabirds are subject to the influences of local climate variables during periods of land-based activities such as breeding and, for some species, moult; particularly if they undergo a catastrophic moult (complete simultaneous moult) as do penguins. We investigated potential relationships between adult penguin survival and land-based climate variables (ambient air temperature, humidity and rainfall) using 46 years of mark-recapture data of little penguins Eudyptula minor gathered at a breeding colony on Phillip Island in southeastern Australia. Our results showed that adult penguin survival had a stronger association with land-based climate variables during the moult period, when birds were unable to go to sea for up to 3 weeks, than during the breeding period, when birds could sacrifice breeding success in favour of survival. Annual adult survival probability was positively associated with humidity during moult and negatively associated with rainfall during moult. Prolonged heat during breeding and moult had a negative association with annual adult survival. Local climate projections suggest increasing days of high temperatures, fewer days of rainfall which will result in more droughts (and by implication, lower humidity) and more extreme rainfall events. All of these predicted climate changes are expected to have a negative impact on adult penguin survival.

  1. A warmer ambient temperature increases the passage of interleukin-1β into the brains of old rats

    Science.gov (United States)

    Buchanan, Jessica B.; Peloso, Elizabeth; Satinoff, Evelyn

    2008-01-01

    We have demonstrated that after intraperitoneal lipopolysaccharide (LPS) injection, old rats mount fevers similar to those of young rats at an ambient temperature (Ta) of 31°C, but not at 21°C. The same is true for intraperitoneal or intravenous IL-1β administration. The underlying mechanism responsible for blunted fever in old rats may be a deficiency in communication between the periphery and the brain. Possibly, peripheral cytokine actions are altered in old rats, such that the signal that reaches the brain is diminished. Here, we hypothesized that at standard laboratory temperatures, not enough IL-1β is reaching the brain for fever to occur and that a warmer Ta would increase the influx of IL-1β into the brain, enabling old rats to generate fever. Young (3–5 mo) and old (23–29 mo) Long-Evans rats were maintained for 3 days at either Ta 21 or 31°C prior to intravenous injection with radiolabeled IL-1β to measure passage across the blood-brain barrier. Young rats showed similar influx of IL-1β into the brain at the two Tas, but old rats showed significant influx only at the warmer Ta. These data suggest that the lack of fever at a cool Ta may be due to a reduced influx of IL-1β into the brain. PMID:18448612

  2. Analysis of the energetic metabolism in cyclic Bedouin goats (Capra hircus): Nychthemeral and seasonal variations of some haematochemical parameters in relation with body and ambient temperatures.

    Science.gov (United States)

    Malek, Mouna; Amirat, Zaina; Khammar, Farida; Khaldoun, Mounira

    2016-08-01

    Several studies have examined changes in some haematochemical parameters as a function of the different physiological status (cyclic, pregnant and lactating) of goats, but no relevant literature has exhaustively investigated these variations from anestrous to estrous stages in cyclic goats. In this paper, we report nychthemeral and seasonal variations in ambient and body temperatures, and in some haematochemical parameters (glycemia, cholesterolemia, triglyceridemia, creatininemia and uremia) measured during summer, winter and spring, in seven (7) experimental cyclic female Bedouin goats (Capra hircus) living in the Béni-Abbès region (Algerian Sahara desert). Cosinor rhythmometry procedure was used to determine the rhythmic parameters of ambient temperature and haematochemical parameters. To determine the effect of time of day on the rhythmicity of the studied parameters, as well as their seasonality, repeated measure analysis of variance (ANOVA) was applied. The results showed that in spite of the nychthemeral profile presented by the ambient temperature for each season, the body temperature remained in a narrow range, thus indicating a successful thermoregulation. The rhythmometry analysis showed a circadian rhythmicity of ambient temperature and haematochemical parameters with diurnal acrophases. A statistically significant effect of the time of day was shown on all studied haematochemical parameters, except on creatininemia. It was also found that only uremia, cholesterolemia and triglyceridemia followed the seasonal sexual activity of the studied ruminant. This study demonstrated the good physiological adaptation developed by this breed in response to the harsh climatic conditions of its natural environment.

  3. Temperature-induced volatility of molecular markers in ambient airborne particulate matter

    Directory of Open Access Journals (Sweden)

    C. R. Ruehl

    2011-01-01

    Full Text Available Molecular markers are organic compounds used to represent known sources of particulate matter (PM in statistical source apportionment studies. The utility of molecular markers depends on, among other things, their ability to represent PM volatility under realistic atmospheric conditions. We measured the particle-phase concentrations and temperature-induced volatility of commonly-used molecular markers in California's heavily polluted San Joaqin Valley. Concentrations of elemental carbon, organic carbon, levoglucosan, and polycyclic aromatic hydrocarbons were not reduced by mild (~10 K heating. In contrast, both hopane/sterane and n-alkane concentrations were reduced, especially during the summer sampling events at the urban site. These results suggest that hopanes and steranes have effective saturation concentrations ~1 μg m−3, and therefore can be considered semi-volatile. The volatility of an individual compound depends both on its inherent properties (primarily vapour pressure and the interactions between itself and any potential absorbing phase. The volatility behavior of n-alkanes during the urban summer is consistent with that predicted for absorption by suberic acid (a C8 diacid using a group contribution modelling method. Observations can also be matched by an absorbent whose composition is based on recently-obtained high-resolution aerosol mass spectrometer factors (approximately 33% "hydrocarbon-like" and 67% oxygenated organic aerosol. The reduced evaporation of the n-alkanes, hopanes, and steranes with mild heating during rural and/or winter experiments could be explained by a more oxygenated absorbing phase along with a non-absorptive partitioning mechanism, such as adsorption to soot. This suggests that the temperature-induced volatility of large hydrocarbons in PM is most important if a relatively non-polar absorbing organic phase exists. While the activity coefficients of most organic

  4. Partial nitrification of non-ammonium-rich wastewater within biofilm filters under ambient temperature.

    Science.gov (United States)

    Wang, Hongyu; He, Jiajie; Yang, Kai

    2010-01-01

    This study evaluated the partial nitrification performances of two biofilm filters over a synthetic non-ammonium-rich wastewater at a 20°C room temperature under both limited DO (∼2.0 mg/L) and unlimited DO (∼4.0 mg/L) conditions. The two filters were each of 80 cm long and used different biofilm carriers: activated carbon and ceramic granule. Results showed that partial nitrification was accomplished for both filters under the limited DO condition. However, the effluent NO(2)-N was higher in the ceramic granule filter than in the activated carbon filter, and was less susceptible to the influent COD/N changes. Further investigation into the water phase COD and NH(4)-N depth profiles and bacteria population within the two filters showed that by putting upper filter layer (upstream) to confront relatively higher influent COD/N ratios, the filtration process naturally put lower filter layers (downstream) relatively more favorable for nitrifying bacteria (ammonia oxidizing bacteria in this study) to prosper, making the filter depth left for nitrification a crucial factor for the effectiveness of nitrification with a filter. The potentially different porous flow velocities of the two filters might be the reason to cause their different partial nitrification performances, with a lower porous flow velocity (the ceramic granule filter) favoring partial nitrification more. In summation, DO, filter depth, and filtration speed should be played together to successfully operate a biofilm filter for partial nitrification.

  5. Association between children's forced vital capacity and long-term exposure to local ambient temperature in China: A national cross-sectional survey.

    Science.gov (United States)

    Li, Qin; Wang, Hai-Jun; Song, Yi; Ma, Jun; Song, Jie-Yun; Guo, Yuming

    2016-07-01

    It is well documented that short-term exposure to extreme ambient temperature is associated with respiratory disorder. However, few studies have assessed the long-term effect of temperature on children's lung function. The present study aimed to investigate the association between long-term exposure to local ambient temperature and children's forced vital capacity (FVC) in China. We analyzed the FVC data of 71,768 children from the 2010 Chinese National Survey on Students' Construction and Health (CHNSCH), and local annual average ambient temperature, relative humidity, air pollutants data from China Meteorological Administration and Ministry of Environment Protection of China. Generalized additive model (GAM) with non-linear function was used to examine the effect of ambient temperature on children's FVC. The results showed that low temperature was significantly associated with decrease of FVC in Chinese children within certain temperature range while adjusting for individual characteristics, socioeconomic conditions, air pollutants and relative humidity. The largest alteration of FVC related to the annual average temperature difference among cities from 20.4°C to 4.5°C was observed, being 242.7ml (95%CI: 220.0, 265.3) decrease in FVC. The similar association was found in both physically active and inactive children, while the largest alteration of FVC related to the temperature difference reached 329.1ml (95%CI: 296.7, 361.6) in physically active children and 290.5ml (95%CI: 255.7, 325.3) in physically inactive ones. Public health policy should be developed for protecting children's respiratory health during growth and development in some areas with cold weather. Key message What is the key question? Few studies have assessed the long-term effect of temperature on children's forced vital capacity (FVC). We analyzed the Chinese national survey data to clarify the association between children's forced vital capacity and long-term exposure to local ambient

  6. Hydration products of lime-metakaolin pastes at ambient temperature with ageing

    Energy Technology Data Exchange (ETDEWEB)

    Gameiro, A., E-mail: agameiro@lnec.pt [National Laboratory of Civil Engineering, Materials Department, Av. do Brasil, 101, 1700 Lisbon (Portugal); Santos Silva, A., E-mail: ssilva@lnec.pt [National Laboratory of Civil Engineering, Materials Department, Av. do Brasil, 101, 1700 Lisbon (Portugal); Veiga, R., E-mail: rveiga@lnec.pt [National Laboratory of Civil Engineering, Buildings Department, Av. do Brasil, 101, 1700 Lisbon (Portugal); Velosa, A., E-mail: avelosa@ua.pt [Department of Civil Engineering, Geobiotec, University of Aveiro, Campus Universitario de Santiago, 3810-193 Aveiro (Portugal)

    2012-05-10

    Highlights: Black-Right-Pointing-Pointer We study the compounds formed in lime/MK blended pastes and their stability over time. Black-Right-Pointing-Pointer Different mixes of lime/MK pastes show different reaction kinetics during curing time, being the pozzolanic compounds formed directly proportional to the lime by MK replacement. Black-Right-Pointing-Pointer Some pozzolanic products are found to be unstable during the hydration reaction employed in our study. - Abstract: Mortars constituted of lime mixtures with pozzolanic additions have been extensively used in the past for the construction of historic and traditional buildings. This paper presents the results of blended pastes of lime and metakaolin (MK), namely compounds formed and their stability over time. This research is part of an extensive study aiming at the formulation of lime based mortars for restoration purposes. It has been shown for several years that MK has been applied in inorganic binders due to its capacity to react vigorously with calcium hydroxide (CH). In the presence of water originating a series of major hydrated phases, namely tetra calcium aluminate hydrate (C{sub 4}AH{sub 13}), calcium silicates hydrates (CSH) and calcium aluminium silicate hydrates (stratlingite - C{sub 2}ASH{sub 8}). Several blended pastes of lime and MK, with different substitution rates of lime by MK (wt%) were prepared and cured at a temperature of 20 Degree-Sign C and relative humidity RH > 95%. The phase composition of the formed hydrated phases was determined by X-ray diffraction (XRD) and simultaneous thermal analysis (TG-DTA). The obtained results showed that lime/MK pastes compositions displayed different reaction kinetics during curing time, being the pozzolanic products content directly proportional to the substitution rate of lime by MK. Also, a relationship between the increase stratlingite content and the MK substitution rate of lime by MK was found.

  7. A moderate increase in ambient temperature modulates the Atlantic cod (Gadus morhua spleen transcriptome response to intraperitoneal viral mimic injection

    Directory of Open Access Journals (Sweden)

    Hori Tiago S

    2012-08-01

    pIC at 10°C vs. 16°C at 6HPI. These results substantially increase our understanding of the genes and molecular pathways involved in the negative impacts of elevated ambient temperature on fish health, and may also be valuable to our understanding of how accelerated global climate change could impact cold-water marine finfish species.

  8. Mechanical Behavior and Thermal Stability of Acid-Base Phosphate Cements and Composites Fabricated at Ambient Temperature

    Science.gov (United States)

    Colorado Lopera, Henry Alonso

    This dissertation presents the study of the mechanical behavior and thermal stability of acid-base phosphate cements (PCs) and composites fabricated at ambient temperature. These materials are also known as chemically bonded phosphate ceramics (CBPCs). Among other advantages of using PCs when compared with traditional cements are the better mechanical properties (compressive and flexural strength), lower density, ultra-fast (controllable) setting time, controllable pH, and an environmentally benign process. Several PCs based on wollastonite and calcium and alumino phosphates after thermal exposure up to 1000°C have been investigated. First, the thermo-mechanical and chemical stability of wollastonite-based PC (Wo-PC) exposed to temperatures up to 1000°C in air environment were studied. The effects of processing conditions on the curing and shrinkage of the wollastonite-based PC were studied. The chemical reactions and phase transformations during the fabrication and during the thermal exposure are analyzed in detail using scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermo-gravimetric analysis (TGA Then, the thermo-mechanical and chemical stability of glass, carbon and basalt fiber reinforced Wo-PC composites, were studied using SEM, XRD, TGA. The flexural strength and Weibull statistics were analyzed. A significant strength degradation in the composites were found after the thermal exposure at elevated temperatures due to the interdifusion and chemical reactions across the fibers and the matrix at temperatures over 600°C. To overcome this barrier, we have developed a new PC based on calcium and alumino-phosphates (Ca-Al PCs). The Ca-Al PCs were studied in detail using SEM, XRD, TGA, curing, shrinkage, Weibull statistics, and compression tests. Our study has confirmed that this new composite material is chemically and mechanically stable at temperatures up to 1000°C. Moreover, the compression strength increases after exposure to 1000

  9. Optimal foraging behavior and the thermal neutral zone of Peromyscus leucopus during winter: A test using natural and controlled ambient temperatures.

    Science.gov (United States)

    St Juliana, Justin R; Mitchell, William A

    2016-02-01

    Endotherms foraging at temperatures outside of their thermal neutral zone (TNZ) pay an increased energetic cost. We asked if thermally-induced changes in foraging costs influence quitting harvest rate (QHR) of mice. We predicted that mice foraging during the winter would have a higher QHR in more costly colder conditions. We conducted our study with wild caught Peromyscus leucopus in an enclosure located in West Terre Haute, Indiana. We assayed changes in QHR using the forager's giving up density (GUD), which is the amount of uneaten seeds reaming in a tray after foraging activity. Each night from January 12th to March 13th, we assigned 4 trays as "cold trays" (at ambient temperature), and 4 trays as "hot trays" (trays with a ceramic heat element that increased the temperatures of feeding trays ca. 10-15°C). GUDs (and therfore QHRs) increased as a function of decreasing ambient temperature. Furthermore there was an interaction between tray temperature and ambient temperature; namely, on cool nights mice had lower GUDs in the "hot trays", but on warm nights mice had lower GUDs in the "cold trays". The TNZ for P. leucopus actively foraging during winter may be closer to the environmental average temperature than typically measured in the laboratory. Overall, these results support the idea that QHR is related to an animal's foraging in thermally challenged conditions. We present a unique way of measuring an animal's TNZ in the field using behavioral indicators.

  10. The influence of the starvation-predation trade-off on the relationship between ambient temperature and body size among endotherms

    NARCIS (Netherlands)

    McNamara, John M.; Higginson, Andrew D.; Verhulst, Simon

    2016-01-01

    Aim: The tendency for animals at higher latitudes to be larger (Bergmann's rule) is generally explained by recourse to latitudinal effects on ambient temperature and the food supply, but these receive only mixed support and do not explain observations of the inverse to Bergmann's rule. Our aim was t

  11. Ambient-temperature trap/release of arsenic by dielectric barrier discharge and its application to ultratrace arsenic determination in surface water followed by atomic fluorescence spectrometry

    Science.gov (United States)

    A novel dielectric barrier discharge reactor (DBDR) was utilized to trap/release arsenic coupled to hydride generation atomic fluorescence spectrometry (HGAFS). On the DBD principle, the precise and accurate control of trap/release procedures was fulfilled at ambient temperature, and an analytical m...

  12. Observation of immobile regions in natural rubber at ambient temperature by solid-state C-13 CP/MAS NMR spectroscopy

    DEFF Research Database (Denmark)

    Larsen, F.H.; Rasmussen, T.; Pedersen, Walther Batsberg

    1999-01-01

    Employing C-13 CP/MAS NMR spectroscopy, the existence of immobile regions in natural rubber (cis-1,4-polyisoprene) corresponding to a few percent of the monomer units has been detected at ambient temperature. For synthetic rubbers no immobile regions have been detected at all. Applying different...

  13. Effects of ambient temperature and oxygen concentration on diesel spray combustion using a single-nozzle injector in a constant volume combustion chamber

    KAUST Repository

    Jing, Wei

    2013-09-02

    This work investigates the effects of ambient conditions on diesel spray combustion in an optically accessible, constant volume chamber using a single-nozzle fuel injector. The ambient O2 concentration was varied between five discrete values from 10% to 21% and three different ambient temperatures (800 K, 1000 K, and 1200 K). These conditions simulate different exhaust gas recirculation (EGR) levels and ambient temperatures in diesel engines. Both conventional diesel combustion and low temperature combustion (LTC) modes were observed under these conditions. A transient analysis and a quasi-steady state analysis are employed in this article. The transient analysis focuses on the flame development from beginning to the end, illustrating how the flame structure changes during this process; the quasi-steady state analysis focuses on the stable flame structure. The transient analysis was conducted using high-speed imaging of both OH* chemiluminescence and natural luminosity (NL). In addition, three different images were acquired using an ICCD camera, corresponding to OH* chemiluminescence, narrow-band flame emission at 430 nm (Band A) and at 470 nm (Band B), and were used to investigate the quasi-steady state combustion process. From the transient analysis, it was found that the NL signal becomes stronger and confined to narrow regions when the temperature and O2 concentration increase during the development of flame. The OH* intensity is much lower for the 10% ambient O2 and 800 K conditions compared to the higher temperatures and O2 levels. This implies the occurrence of LTC under these conditions. Results from the quasi-steady combustion stage indicate that high-temperature reactions effectively oxidize the soot in the downstream locations where only OH* signal is observed. In addition, an area was calculated for each spectral region, and results show that the area of Band A and Band B emissions in these images is larger than the area of OH* emissions at the lower O2

  14. Performance of a completely autotrophic nitrogen removal over nitrite process for treating wastewater with different substrates at ambient temperature

    Institute of Scientific and Technical Information of China (English)

    Xiaoyan Chang; Dong Li; Yuhai Liang; Zhuo Yang; Shaoming Cui; Tao Liu; Huiping Zeng

    2013-01-01

    The stability and parameters of a bio-ceramic filter for completely autotrophic nitrogen removal were investigated.The completely autotrophic nitrogen removal over nitrite (CANON) reactor was fed with different concentrations of ammonia (400,300,and 200 mg N/L) but constant influent ammonia load.The results showed that the CANON system can achieve good treatment performance at ambient temperature (15-23℃).The average removal rate and removal loading of NH4 +-N and TN was 83.90%,1.26 kg N/(m3.day),and 70.14%,1.09 kg N/(m3.day),respectively.Among the influencing factors like pH,dissolved oxygen and alkalinity,it was indicated that the pH was the key parameter of the performance of the CANON system.Observing the variation of pH would contribute to better control of the CANON system in an intuitive and fast way.Denaturing gradient gel electrophoresis analysis of microorganisms further revealed that there were some significant changes in the community structure of ammonium oxidizing bacteria,which had low diversity in different stages,while the species of anaerobic ammonium oxidizing (anammox) bacteria were fewer and the community composition was relatively stable.These observations showed that anaerobic ammonia oxidation was more stable than the aerobic ammonia oxidation,which could explain that why the CANON system maintained a good removal efficiency under the changing substrate conditions.

  15. In Situ Ambient Pressure X-ray Photoelectron Spectroscopy of Cobalt Perovskite Surfaces under Cathodic Polarization at High Temperatures

    KAUST Repository

    Crumlin, Ethan J.

    2013-08-08

    Heterostructured oxide interfaces have demonstrated enhanced oxygen reduction reaction rates at elevated temperatures (∼500-800 C); however, the physical origin underlying this enhancement is not well understood. By using synchrotron-based in situ ambient pressure X-ray photoelectron spectroscopy (APXPS), we focus on understanding the surface electronic structure, elemental composition, and chemical nature of epitaxial La0.8Sr 0.2CoO3-δ (LSC113), (La 0.5Sr0.5)2CoO4±δ (LSC214), and LSC214-decorated LSC113 (LSC 113/214) thin films as a function of applied electrical potentials (0 to -800 mV) at 520 C and p(O2) of 1 × 10-3 atm. Shifts in the top of the valence band binding energy and changes in the Sr 3d and O 1s spectral components under applied bias reveal key differences among the film chemistries, most notably in the degree of Sr segregation to the surface and quantity of active oxygen sites in the perovskite termination layer. These differences help to identify important factors governing the enhanced activity of oxygen electrocatalysis observed for the LSC113/214 heterostructured surface. © 2013 American Chemical Society.

  16. Lithium plating in lithium-ion batteries at sub-ambient temperatures investigated by in situ neutron diffraction

    Science.gov (United States)

    Zinth, Veronika; von Lüders, Christian; Hofmann, Michael; Hattendorff, Johannes; Buchberger, Irmgard; Erhard, Simon; Rebelo-Kornmeier, Joana; Jossen, Andreas; Gilles, Ralph

    2014-12-01

    Lithium plating in commercial LiNi1/3Mn1/3Co1/3O2/graphite cells at sub-ambient temperatures is studied by neutron diffraction at Stress-Spec, MLZ. Li plating uses part of the active lithium in the cell and competes with the intercalation of lithium into graphite. As a result, the degree of graphite lithiation during and after charge is lower. Comparison of graphite lithiation after a C/5 charging cycle fast enough to expect a considerable amount of Li plating with a much slower C/30 reference cycle reveals a lower degree of graphite lithiation in the first case; neutron diffraction shows less LiC6 and more LiC12 is present. If the cell is subjected to a 20 h rest period after charge, a gradual transformation of remaining LiC12 to LiC6 can be observed, indicating Li diffusion into the graphite. During the rest period after the C/5 charging cycle, the degree of graphite lithiation can be estimated to increase by 17%, indicating at least 17% of the active lithium is plated. Data collected during discharge immediately after C/5 charging give further evidence of the presence and amount of metallic lithium: in this case 19% of discharge capacity originates from the oxidation of metallic lithium. Also, lithium oxidation can be directly related to the high voltage plateau observed during discharge in case of lithium plating.

  17. Lithium-functionalized metal-organic frameworks that show >10 wt% H2 uptake at ambient temperature.

    Science.gov (United States)

    Han, Sang Soo; Jung, Dong Hyun; Choi, Seung-Hoon; Heo, Jiyoung

    2013-08-26

    We have used grand canonical Monte Carlo simulations with a first-principles-based force field to show that metal-organic frameworks (MOFs) with Li functional groups (i.e. C-Li bonds) allow for exceptional H2 uptake at ambient temperature. For example, at 298 K and 100 bar, IRMOF-1-4Li shows a total H2 uptake of 5.54 wt% and MOF-200-27Li exhibits a total H2 uptake of 10.30 wt%, which are much higher than the corresponding values with pristine MOFs. Li-functionalized MOF-200 (MOF-200-27Li) shows 11.84 wt% H2 binding at 243 K and 100 bar. These hydrogen-storage capacities exceed the 2015 DOE target of 5.5 wt% H2. Moreover, the incorporation of Li functional groups into MOFs provides more benefits, such as higher delivery amount, for H2 uptake than previously reported Li-doped MOFs.

  18. Efficient production of optically pure L-lactic acid from food waste at ambient temperature by regulating key enzyme activity.

    Science.gov (United States)

    Li, Xiang; Chen, Yinguang; Zhao, Shu; Chen, Hong; Zheng, Xiong; Luo, Jinyang; Liu, Yanan

    2015-03-01

    Bio-production of optically pure L-lactic acid from food waste has attracted much interest as it can treat organic wastes with simultaneous recovery of valuable by-products. However, the yield of L-lactic acid was very low and no optically pure L-lactic acid was produced in the literature due to (1) the lower activity of enzymes involved in hydrolysis and L-lactic acid generation, and (2) the participation of other enzymes related to D-lactic acid and acetic and propionic acids production. In this paper, a new strategy was reported for effective production of optically pure L-lactic acid from food waste at ambient temperature, i.e. via regulating key enzyme activity by sewage sludge supplement and intermittent alkaline fermentation. It was found that not only optically pure L-lactic acid was produced, but the yield was enhanced by 2.89-fold. The mechanism study showed that the activities of enzymes relevant to food waste hydrolysis and lactic acid production were enhanced, and the key enzymes related to volatile fatty acids and D-lactic acid generations were severally decreased or inhibited. Also, the microbes responsible for L-lactic acid production were selectively proliferated. Finally, the pilot-scale continuous experiment was conducted to testify the feasibility of this new technique.

  19. Vitamin E and organic selenium enhances the antioxidative status and quality of chicken semen under high ambient temperature.

    Science.gov (United States)

    Ebeid, T A

    2012-01-01

    1. The effects of supplemental dietary vitamin E and organic selenium (Se), and their combination, on improving semen quality characteristics and antioxidative status were investigated in cockerels exposed to high ambient temperature. 2. A total of 36 Egyptian local cross males, 40 weeks old, were housed individually in cages in an open-sided building (average daily temperature ranged from 33 to 36°C and relative humidity from 60 to 70%). Birds were divided randomly into 4 experimental treatments (n=9 each): (1) control (basal diet without any supplementation with vitamin E or Se); (2) vitamin E (basal diet +200 mg α-tocopherol acetate/kg diet); (3) Se (basal diet +0.3 mg organic Se/kg diet); and (4) vitamin E+Se (basal diet +200 mg α-tocopherol acetate/kg diet +0.3 mg organic Se/kg diet). 3. Under heat stress conditions, inclusion of vitamin E and/or organic Se in the diets enhanced the semen quality traits, including the spermatozoa count and motility, and reduced the percentage of dead spermatozoa. 4. A combination of 200 mg/kg vitamin E with 0.3 mg/kg organic Se reduced the thiobarbituric acid reactive substance concentration in seminal plasma samples to about 28% of the controls; and also enhanced the seminal plasma glutathione peroxidase activity by two-fold compared with controls. 5. It was concluded that dietary vitamin E in combination with organic Se has a synergistic effect in minimising lipid peroxidation and improving the antioxidative status in seminal plasma of the domestic fowl, which probably translated into enhanced spermatozoa count, motility and reduced percentage of dead spermatozoa under heat stress conditions.

  20. Physiological Effects of Ergot Alkaloid and Indole-Diterpene Consumption on Sheep under Hot and Thermoneutral Ambient Temperature Conditions.

    Science.gov (United States)

    Henry, Michelle L E; Kemp, Stuart; Dunshea, Frank R; Leury, Brian J

    2016-06-02

    A controlled feeding study was undertaken to determine the physiological and production effects of consuming perennial ryegrass alkaloids (fed via seed) under extreme heat in sheep. Twenty-four Merino ewe weaners (6 months; initial BW 30.8 ± 1.0 kg) were selected and the treatment period lasted 21 days following a 14 day acclimatisation period. Two levels of two factors were used. The first factor was alkaloid, fed at a nil (NilAlk) or moderate level (Alk; 80 μg/kg LW ergovaline and 20.5 μg/kg·LW lolitrem B). The second factor was ambient temperature applied at two levels; thermoneutral (TN; constant 21-22 °C) or heat (Heat; 9:00 AM-5:00 PM at 38 °C; 5:00 PM-9:00 AM at 21-22 °C), resulting in four treatments, NilAlk TN, NilAlk Heat, Alk TN and Alk Heat. Alkaloid consumption reduced dry matter intake ( p = 0.008), and tended to reduce liveweight ( p = 0.07). Rectal temperature and respiration rate were increased by both alkaloid and heat ( p < 0.05 for all). Respiration rate increased to severe levels when alkaloid and heat were combined, indicating the short term effects which may be occurring in perennial ryegrass toxicosis (PRGT) areas during severe weather conditions, a novel finding. When alkaloid ingestion and heat were administered separately, similar physiological responses occurred, indicating alkaloid ingestion causes a similar heat stress response to 38 °C heat.

  1. Physiological Effects of Ergot Alkaloid and Indole-Diterpene Consumption on Sheep under Hot and Thermoneutral Ambient Temperature Conditions

    Directory of Open Access Journals (Sweden)

    Michelle L. E. Henry

    2016-06-01

    Full Text Available A controlled feeding study was undertaken to determine the physiological and production effects of consuming perennial ryegrass alkaloids (fed via seed under extreme heat in sheep. Twenty-four Merino ewe weaners (6 months; initial BW 30.8 ± 1.0 kg were selected and the treatment period lasted 21 days following a 14 day acclimatisation period. Two levels of two factors were used. The first factor was alkaloid, fed at a nil (NilAlk or moderate level (Alk; 80 μg/kg LW ergovaline and 20.5 μg/kg·LW lolitrem B. The second factor was ambient temperature applied at two levels; thermoneutral (TN; constant 21–22 °C or heat (Heat; 9:00 AM–5:00 PM at 38 °C; 5:00 PM–9:00 AM at 21–22 °C, resulting in four treatments, NilAlk TN, NilAlk Heat, Alk TN and Alk Heat. Alkaloid consumption reduced dry matter intake ( p = 0.008, and tended to reduce liveweight ( p = 0.07. Rectal temperature and respiration rate were increased by both alkaloid and heat ( p < 0.05 for all. Respiration rate increased to severe levels when alkaloid and heat were combined, indicating the short term effects which may be occurring in perennial ryegrass toxicosis (PRGT areas during severe weather conditions, a novel finding. When alkaloid ingestion and heat were administered separately, similar physiological responses occurred, indicating alkaloid ingestion causes a similar heat stress response to 38 °C heat.

  2. Diurnal variations of airborne pollen concentration and the effect of ambient temperature in three sites of Mexico City

    Science.gov (United States)

    Ríos, B.; Torres-Jardón, R.; Ramírez-Arriaga, E.; Martínez-Bernal, A.; Rosas, I.

    2016-05-01

    Pollen is an important cause of allergic respiratory ailments in the Mexico City Metropolitan Area (MCMA). However, very little is known if ambient air temperature correlates with the early blooming of plants observed in other urban areas around the world. A research study was conducted during the dry season of 2012-2013 at three representative sites of the MCMA with different urban characteristics with the aim to understand the relationships between the profusion and diversity of pollen against temperature and other meteorological variables and degree of urbanization. Pollen samples were collected using a Hirst-type trap sampler in the sites: Merced (highly urbanized), Iztapalapa (medium-high urbanized) and Coyoacan (moderately urbanized). Urbanization levels were determined using a composite index based on population density, proportion of surface covered by construction and asphalt, and urban heat island intensity. A set of representative pollen sampling tapes were assayed under a light microscope at magnification of ×1,000 and converted to grains per cubic meter. The most representative pollen types found in the three sites were, regardless of urbanization levels were: Fraxinus, Cupressaceae/Taxodiaceae, Casuarina, Alnus, Myrtaceae, and Pinus. Total pollen concentration was greatest in the moderately urbanized area, although earlier blooming took place at the highly urbanized zone. Total pollen concentration in the medium-high urbanized site has the lowest because the green areas in this zone of MCMA are few. In a diurnal basis, the most abundant pollen types peaked near midday or in the afternoon evening at the three sites. A Spearman test showed a positive correlation among bihourly pollen concentrations, temperature and relative humidity in all sites, but wind speed just correlated in Iztapalapa and Coyoacan. The results obtained suggest that Urban Heat Island Intensity can disturb flowering periods and pollen concentrations, largely in the highly urbanized

  3. Diurnal variations of airborne pollen concentration and the effect of ambient temperature in three sites of Mexico City.

    Science.gov (United States)

    Ríos, B; Torres-Jardón, R; Ramírez-Arriaga, E; Martínez-Bernal, A; Rosas, I

    2016-05-01

    Pollen is an important cause of allergic respiratory ailments in the Mexico City Metropolitan Area (MCMA). However, very little is known if ambient air temperature correlates with the early blooming of plants observed in other urban areas around the world. A research study was conducted during the dry season of 2012-2013 at three representative sites of the MCMA with different urban characteristics with the aim to understand the relationships between the profusion and diversity of pollen against temperature and other meteorological variables and degree of urbanization. Pollen samples were collected using a Hirst-type trap sampler in the sites: Merced (highly urbanized), Iztapalapa (medium-high urbanized) and Coyoacan (moderately urbanized). Urbanization levels were determined using a composite index based on population density, proportion of surface covered by construction and asphalt, and urban heat island intensity. A set of representative pollen sampling tapes were assayed under a light microscope at magnification of ×1,000 and converted to grains per cubic meter. The most representative pollen types found in the three sites were, regardless of urbanization levels were: Fraxinus, Cupressaceae/Taxodiaceae, Casuarina, Alnus, Myrtaceae, and Pinus. Total pollen concentration was greatest in the moderately urbanized area, although earlier blooming took place at the highly urbanized zone. Total pollen concentration in the medium-high urbanized site has the lowest because the green areas in this zone of MCMA are few. In a diurnal basis, the most abundant pollen types peaked near midday or in the afternoon evening at the three sites. A Spearman test showed a positive correlation among bihourly pollen concentrations, temperature and relative humidity in all sites, but wind speed just correlated in Iztapalapa and Coyoacan. The results obtained suggest that Urban Heat Island Intensity can disturb flowering periods and pollen concentrations, largely in the highly urbanized

  4. Correlation of rectal temperature and peripheral temperature from implantable radio-frequency microchips in Holstein steers challenged with lipopolysaccharide under thermoneutral and high ambient temperatures.

    Science.gov (United States)

    Reid, E D; Fried, K; Velasco, J M; Dahl, G E

    2012-12-01

    Early detection of disease can speed treatment, slow spread of disease in a herd, and improve health status of animals. Immune stimulation increases rectal temperature (RT). Injectable radio-frequency implants (RFI) can provide temperature at the site of implantation. The fidelity of peripheral site temperature, determined by RFI, relative to RT is unknown in cattle. We hypothesized that during lipopolysaccharide (LPS) challenge, temperature at 3 peripheral sites would be similar to RT in steers (n = 4; BW 77 ± 2.1 kg). The 3 sites were 1) subcutaneous (SC) at the base of the ear (ET); 2) SC posterior to the poll (PT); and 3) SC beneath the umbilical fold (UT). Steers were housed in controlled temperature (CT) rooms (between 18 and 21°C; n = 2/room). Rectal temperature, ET, PT, and UT were recorded every 8 h daily. On d 7, 21, 22, 36, and 37, RT and RFI were taken every 5 min for 6 h, every 15 min for 3 h, and every 30 min for 15 h. To test RFI during a simulated immune challenge, LPS (E. coli 055:B5) was injected intravenously (i.v.) at 1000 h on d 22 and 37. Basal temperatures (°C) were RT (38.7 ± 0.20), ET (37.1 ± 0.86), PT (36.7 ± 0.57), and UT (36.3 ± 0.97). Rectal temperature increased to 39.9 ± 0.30°C after LPS, but ET, PT, and UT decreased. Heat stress also increases RT, which makes it difficult to identify sick animals using RT. The second hypothesis tested was that ET positively correlates to RT and negatively correlates to RT during LPS under heat stress. Four steers (127 ± 7.3 kg) were housed in CT chambers (n = 2/chamber), implanted with a RFI, and allowed 2 wk to acclimate. One chamber remained at 20°C, the other was increased to 34°C starting at 0800 h for a period of 48 h. The LPS was administered i.v. to all steers at 1000 h on d 2. After a 2-wk recovery at 20°C, the temperature was increased in the other chamber, resulting in a crossover design with each steer serving as its own control. Pearson's correlation coefficients for ET and

  5. Disturbances in pro-oxidant-antioxidant balance after passive body overheating and after exercise in elevated ambient temperatures in athletes and untrained men.

    Directory of Open Access Journals (Sweden)

    Wanda Pilch

    Full Text Available The aim of the study was to investigate pro-oxidant-antioxidant balance in two series of examinations with two types of stressors (exogenous heat and the combined exogenous and endogenous heat in trained and untrained men. The exogenous stressor was provided by Finnish sauna session, whereas the combined stressor was represented by the exercise in elevated ambient temperature. The men from the two groups performed the physical exercise on a cycle ergometer with the load of 53 ± 2% maximal oxygen uptake at the temperature of 33 ± 1 °C and relative humidity of 70% until their rectal temperature rose by 1.2 °C. After a month from completion of the exercise test the subjects participated in a sauna bathing session with the temperature of 96 ± 2 °C, and relative humidity of 16 ± 5%. 15-minutes heating and 2-minute cool-down in a shower with the temperature of 20 °C was repeated until rectal temperature rose by 1.2 °C compared to the initial value. During both series of tests rectal temperature was measured at 5-minute intervals. Before both series of tests and after them body mass was measured and blood samples were taken for biochemical tests. Serum total protein, serum concentration of lipid peroxidation products and serum antioxidants were determined. The athletes were characterized by higher level of antioxidant status and lower concentration of lipid peroxidation products. Physical exercise at elevated ambient temperature caused lower changes in oxidative stress indices compared to sauna bathing. Sauna induced a shift in pro-oxidant-antioxidant balance towards oxidation, which was observed less intensively in the athletes compared to the untrained men. This leads to the conclusion that physical exercise increases tolerance to elevated ambient temperature and oxidative stress.

  6. Variability of Battery Wear in Light Duty Plug-In Electric Vehicles Subject to Ambient Temperature, Battery Size, and Consumer Usage: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wood, E.; Neubauer, J.; Brooker, A. D.; Gonder, J.; Smith, K. A.

    2012-08-01

    Battery wear in plug-in electric vehicles (PEVs) is a complex function of ambient temperature, battery size, and disparate usage. Simulations capturing varying ambient temperature profiles, battery sizes, and driving patterns are of great value to battery and vehicle manufacturers. A predictive battery wear model developed by the National Renewable Energy Laboratory captures the effects of multiple cycling and storage conditions in a representative lithium chemistry. The sensitivity of battery wear rates to ambient conditions, maximum allowable depth-of-discharge, and vehicle miles travelled is explored for two midsize vehicles: a battery electric vehicle (BEV) with a nominal range of 75 mi (121 km) and a plug-in hybrid electric vehicle (PHEV) with a nominal charge-depleting range of 40 mi (64 km). Driving distance distributions represent the variability of vehicle use, both vehicle-to-vehicle and day-to-day. Battery wear over an 8-year period was dominated by ambient conditions for the BEV with capacity fade ranging from 19% to 32% while the PHEV was most sensitive to maximum allowable depth-of-discharge with capacity fade ranging from 16% to 24%. The BEV and PHEV were comparable in terms of petroleum displacement potential after 8 years of service, due to the BEV?s limited utility for accomplishing long trips.

  7. Response of the modern lactating sow and progeny to source and level of supplemental dietary fat during high ambient temperatures.

    Science.gov (United States)

    Rosero, D S; van Heugten, E; Odle, J; Arellano, C; Boyd, R D

    2012-08-01

    The objective of this study was to determine the response to increments of 2 sources of dietary fat on lactating sow and progeny performance during high ambient temperatures. Data were collected from 391 sows (PIC Camborough) from June to September in a 2,600-sow commercial unit in Oklahoma. Sows were randomly assigned to a 2 × 3 factorial arrangement of treatments and a control diet. Factors included 1) fat sources, animal-vegetable blend (A-V) and choice white grease (CWG), and 2) fat levels (2%, 4%, and 6%). The A-V blend contained 14.5% FFA with an iodine value of 89, peroxide value of 4.2 mEq/kg, and anisidine value of 23, whereas CWG contained 3.7% FFA with an iodine value of 62, peroxide value of 9.8 mEq/kg, and anisidine value of 5. Diets were corn-soybean meal based, with 8.0% distillers dried grains with solubles and 6.0% wheat middlings, and contained 3.56-g standardized ileal digestible Lys/Mcal ME. Sows were balanced by parity, with 192 and 199 sows representing parity 1 and parity 3 to 5, respectively. Feed refusal increased linearly (P feed and energy intake increased linearly (P Sows fed CWG diets had reduced (linear, P sow and litter gain relative to feed intake) compared with the G:F of sows fed the control diet or the diets containing the A-V blend (0.50, 0.43, and 0.44, respectively; P feed efficiency than CWG. Subsequent litter size and reproductive performance was improved by inclusion of both sources of fat in diets fed to lactating sows.

  8. Degradation of phenol in an upflow anaerobic sludge blanket(UASB) reactor at ambient temperatureKE

    Institute of Scientific and Technical Information of China (English)

    KE Shui-zhou1; SHI Zhou; ZHANG Tong; Herbert H. P. FANG

    2004-01-01

    A synthetic wastewater containing phenol as sole substrate was treated in a 2.8 L upflow anaerobic sludge blanket(UASB) reactor at ambient temperature. The operation conditions and phenol removal efficiency were discussed, microbial population in the UASB sludge was identified based on DNA cloning, and pathway of anaerobic phenol degradation was proposed. Phenol in wastewater was degraded in an UASB reactor at loading rate up to 18 gCOD/(L·d), With a 1:1 recycle ratio, at 26(1℃, pH 7.0-7.5. An UASB reactor was able to remove 99% of phenol up to 1226 mg/L in wastewater with 24 h of hydraulic retention time(HRT). For HRT below 24 h, phenol degradation efficiency decreased with HRT, from 95.4% at 16 h to 93.8% at 12 h. It further deteriorated to 88.5% when HRT reached 8 h. When the concentration of influent phenol of the reactor was 1260 mg/L(corresponding COD 3000 mg/L), with the HRT decreasing(from 40 h to 4 h, corresponding COD loading increasing), the biomass yields tended to increase from 0.265 to 3.08 g/(L·d). While at 12 h of HRT, the biomass yield was lower. When HRT was 12 h, the methane yield was 0.308 L/(gCOD removed), which was the highest. Throughout the study, phenol was the sole organic substrate. The effluent contained only residual phenol without any detectable intermediates, such as benzoate, 4-hydrobenzoate or volatile fatty acids(VFAs). Based on DNA cloning analysis, the sludge was composed of five groups of microorganisms. Desulfotomaculum and Clostridium were likely responsible for the conversion of phenol to benzoate, which was further degraded by Syntrophus to acetate and H2/CO2. Methanogens lastly converted acetate and H2/CO2 to methane. The role of epsilon-Proteobacteria was, however, unsure.

  9. Ambient and elevated temperature fracture and cyclic-fatigue properties in a series of Al-containing silicon carbides

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Rong [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    A series of in situ toughened, Al, B and C containing, silicon carbide ceramics (ABC-SiC) has been examined with Al contents varying from 3 to 7 wt%. With increasing Al additions, the grain morphology in the as-processed microstructures varied from elongated to bimodal to equiaxed, with a change in the nature of the grain-boundary film from amorphous to partially crystalline to fully crystalline. Fracture toughness and cyclic fatigue tests on these microstructures revealed that although the 7 wt.% Al containing material (7ABC) was extremely brittle, the 3 and particularly 5 wt.% Al materials (3ABC and 5ABC, respectively) displayed excellent crack-growth resistance at both ambient (25°C) and elevated (1300 C) temperatures. Indeed, no evidence of creep damage, in the form of grain-boundary cavitation, was seen at temperatures at 1300°C or below. The enhanced toughness of the higher Al-containing materials was associated with extensive crack bridging from both interlocking grains (in 3ABC) and uncracked ligaments (in 5ABC); in contrast, the 7ABC SiC showed no such bridging, concomitant with a marked reduction in the volume fraction of elongated grains. Mechanistically, cyclic fatigue-crack growth in 3ABC and 5ABC SiC involved the progressive degradation of such bridging ligaments in the crack wake, with the difference in the degree of elastic vs. frictional bridging affecting the slope, i.e., Paris law exponent, of the crack-growth curve. In addition an investigation of fracture resistance in non-transforming ceramics toughened by grain bridging mechanism is presented using linear elastic fracture mechanics (LEFM). Linear superposition theorems are used for the superposition of crack opening displacements, as well as stress intensity factors, resulting from the external tractions and the internal compressive bridging stresses. Specifically weight functions are used to relate the CODs, stress intensity factors, and tractions and the bridging stress. Expressions are

  10. Activity, sleep and ambient light have a different impact on circadian blood pressure, heart rate and body temperature rhythms.

    Science.gov (United States)

    Gubin, D G; Weinert, D; Rybina, S V; Danilova, L A; Solovieva, S V; Durov, A M; Prokopiev, N Y; Ushakov, P A

    2017-02-16

    The aim of the present study was to investigate the impact of endogenous and exogenous factors for the expression of the daily rhythms of body temperature (BT), blood pressure (BP) and heart rate (HR). One hundred and seventy-three young adults (YA), 17-24 years old (y.o.), of both genders were studied under a modified constant-routine (CR) protocol for 26 h. Participants were assigned randomly to groups with different lighting regimens: CR-LD, n = 77, lights (>400 l×) on from 09:00 to 17:00 h and off (400 l×) during the whole experimental session; CR-DD, n = 15, constant dim light (measured every 2 h. For comparison, the results of the former studies performed under conditions of regular life with an activity period from 07:00 to 23:00 h and sleep from 23:00 till 07:00 h (Control) were reanalyzed. Seven-day Ambulatory Blood Pressure Monitoring (ABPM) records from 27 YA (16-38 y.o.) and BT self-measurement data from 70 YA (17-30 y.o.) taken on ≥ 3 successive days at 08:00, 11:00, 14:00, 17:00, 20:00, 23:00 and 03:00 were available. The obtained daily patterns were different between Control and CR-DD groups, due to effects of activity, sleep and light. The comparison of Control and CR-LD groups allowed the effects of sleep and activity to be estimated since the lighting conditions were similar. The activity level substantially elevated SBP, but not DBP. Sleep, on the other hand, lowered the nighttime DBP, but has no effect on SBP. HR was affected both by activity and sleep. In accordance with previous studies, these results confirm that the steep BP increase in the morning is not driven by the circadian clock, but rather by sympathoadrenal factors related to awakening and corresponding anticipatory mechanisms. The effect on BT was not significant. To investigate the impact of light during the former dark time and darkness during the former light time, the CR-LL and CR-DD groups were each compared with the CR-LD group. Light delayed the evening decrease of BT

  11. α-Bromodiazoacetamides – a new class of diazo compounds for catalyst-free, ambient temperature intramolecular C–H insertion reactions

    Directory of Open Access Journals (Sweden)

    Åsmund Kaupang

    2013-07-01

    Full Text Available In this work, we introduce a new class of halodiazocarbonyl compounds, α-halodiazoacetamides, which through a metal-free, ambient-temperature thermolysis perform intramolecular C–H insertions to produce α-halo-β-lactams. When carried out with α-bromodiazoacetamides bearing cyclic side chains, the thermolysis reaction affords bicyclic α-halo-β-lactams, in some cases in excellent yields, depending on the ring size and substitution pattern of the cyclic amide side chains.

  12. Part 2. Association of daily mortality with ambient air pollution, and effect modification by extremely high temperature in Wuhan, China.

    Science.gov (United States)

    Qian, Zhengmin; He, Qingci; Lin, Hung-Mo; Kong, Lingli; Zhou, Dunjin; Liang, Shengwen; Zhu, Zhichao; Liao, Duanping; Liu, Wenshan; Bentley, Christy M; Dan, Jijun; Wang, Beiwei; Yang, Niannian; Xu, Shuangqing; Gong, Jie; Wei, Hongming; Sun, Huilin; Qin, Zudian

    2010-11-01

    Fewer studies have been published on the association between daily mortality and ambient air pollution in Asia than in the United States and Europe. This study was undertaken in Wuhan, China, to investigate the acute effects of air pollution on mortality with an emphasis on particulate matter (PM*). There were three primary aims: (1) to examine the associations of daily mortality due to all natural causes and daily cause-specific mortality (cardiovascular [CVD], stroke, cardiac [CARD], respiratory [RD], cardiopulmonary [CP], and non-cardiopulmonary [non-CP] causes) with daily mean concentrations (microg/m3) of PM with an aerodynamic diameter--10 pm (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), or ozone (O3); (2) to investigate the effect modification of extremely high temperature on the association between air pollution and daily mortality due to all natural causes and daily cause-specific mortality; and (3) to assess the uncertainty of effect estimates caused by the change in International Classification of Disease (ICD) coding of mortality data from Revision 9 (ICD-9) to Revision 10 (ICD-10) code. Wuhan is called an "oven city" in China because of its extremely hot summers (the average daily temperature in July is 37.2 degrees C and maximum daily temperature often exceeds 40 degrees C). Approximately 4.5 million residents live in the core city area of 201 km2, where air pollution levels are higher and ranges are wider than the levels in most cities studied in the published literature. We obtained daily mean levels of PM10, SO2, and NO2 concentrations from five fixed-site air monitoring stations operated by the Wuhan Environmental Monitoring Center (WEMC). O3 data were obtained from two stations, and 8-hour averages, from 10:00 to 18:00, were used. Daily mortality data were obtained from the Wuhan Centres for Disease Prevention and Control (WCDC) during the study period of July 1, 2000, to June 30, 2004. To achieve the first aim, we used a regression of

  13. A meta-analysis of the effects of high ambient temperature on growth performance of growing-finishing pigs.

    Science.gov (United States)

    Renaudeau, D; Gourdine, J L; St-Pierre, N R

    2011-07-01

    High ambient temperature (T) is one of the most important climatic factors influencing pig performance. Increased T occurs sporadically during summer heat waves in temperate climates and year round in tropical climates. Results of published experiments assessing the effects of high T on pig performance are surprisingly variable. Thus, a meta-analysis was performed to aggregate our knowledge and attempt to explain differences in the results across studies on the effect of increased T on ADFI and ADG in growing-finishing pigs. Data for ADFI and ADG were extracted from 86 and 80 trials, respectively, from articles published in scientific journals indexed in PubMed, Science Direct, and from proceedings of scientific meetings through November 2009. Data on ADFI and ADG were analyzed using a linear mixed model that included the linear and the quadratic effects of T and BW, and their interactions as continuous, fixed effects variables, and the trial as a random effect factor (i.e., block). In addition, the effects of housing type (2 levels: individual and group housing) and the year of publication (3 levels: 1970 to 1989, 1990 to 1999, and 2000 to 2009) on the intercept and the linear regression term for T (i.e., the slope) were also tested. Results showed that high T had a curvilinear effect on ADFI and ADG and that this effect was more pronounced in heavier pigs. Across T, ADFI was less when pigs were group-housed. The intercept and the regression coefficient (slope) for T were significantly affected by the year of publication. The effect of increased T was greater in more contemporary works, suggesting that modern genotypes could be more sensitive to heat stress than older genotypes of lesser growth potential. In conclusion, pig performance decreases at an accelerating rate as T is increased. The large between-study variability on the effects of high T on pig performance is partially explained by differences in pig BW and to a lesser extent by the year the study was

  14. The effects of feed restriction and ambient temperature on growth and ascites mortality of broilers reared at high altitude.

    Science.gov (United States)

    Ozkan, S; Takma, C; Yahav, S; Sögüt, B; Türkmut, L; Erturun, H; Cahaner, A

    2010-05-01

    The development of ascites was investigated in broilers at low versus high altitudes, cold versus normal ambient temperatures (AT), and 3 feeding regimens. One-day-old chicks obtained at sea level were reared at high altitude (highA; 1,720 m; n = 576) with 2 AT treatments, low AT from 3 wk onward at highA (highA/cold) and normal AT from 3 wk onward at highA (highA/norm), or at sea level (normal AT from 3 wk onward at low altitude, lowA/norm; n = 540). Under highA/cold, AT ranged between 16 to 17 degrees C in the fourth week, 17 to 19 degrees C in the fifth week, and 19 to 21 degrees C thereafter. Under highA/norm and lowA/norm, AT was 24 degrees C in the fourth week and ranged between 22 to 24 degrees C thereafter. Broilers in each condition were divided into 3 groups: feed restriction (FR) from 7 to 14 d, FR from 7 to 21 d, and ad libitum (AL). Ascites mortality and related parameters were recorded. Low mortality (0.4%) occurred under lowA/norm conditions. Under highA/norm, mortality was lower in females (8.6%) than in males (13.8%) and was not affected by the feeding regimen. The highA/cold treatment resulted in higher mortality but only in males; it was 44.2% among highA/cold AL-fed males and only about 26% under the FR regimens, suggesting that FR helped some males to better acclimatize to the highA/cold environment and avoid ascites. However, mortality was only 13.3% in AL-fed males at highA/norm and FR did not further reduce the incidence of ascites under these conditions. Thus, avoiding low AT in the poultry house by slight heating was more effective than FR in reducing ascites mortality at highA. Compared with FR from 7 to 14 d, FR from 7 to 21 d did not further reduce mortality and reduced growth. At 47 d, the majority of surviving broilers at highA had high levels of hematocrit and right ventricle:total ventricle weight ratio (>0.29), but they were healthy and reached approximately the same BW as their counterparts at low altitude. This finding may

  15. Theoretical modelling of Staphylococcus aureus growth in a cooked meat product kept at ambient temperature using temperature profiles of selected Mexican cities Modelagem teórica de crescimento de Staphylococcus aureus em um produto à base de carne cozida deixada à temperatura ambiente, usando perfis de temperatura de cidades do México

    Directory of Open Access Journals (Sweden)

    Rosa Baeza

    2009-03-01

    Full Text Available A theoretical model is used to predict the growth of Staphylococcus aureus in a pasteurized meat product kept at ambient temperatures for several hours. For this purpose, the temperature profiles of some cities of Mexico were combined with literature data on the kinetics of S. aureus growth. As shown by theoretical predictions, if the food is kept at ambient temperature, the average daily temperature may not give accurate predictions.Um modelo teórico é utilizado para prever o crescimento de Staphylococcus aureus em um produto à base de carne (pasteurizado deixado por várias horas à temperatura ambiente. Para isso, perfis de temperatura de algumas cidades do México foram combinados com resultados de literatura sobre a cinética de crescimento de S. aureus. Como demonstrado por previsões teóricas, se o alimento é deixado à temperatura ambiente, a utilização da média diária da temperatura pode não dar previsões exatas.

  16. Ambient temperature deposition of gallium nitride/gallium oxynitride from a deep eutectic electrolyte, under potential control.

    Science.gov (United States)

    Sarkar, Sujoy; Sampath, S

    2016-05-11

    A ternary, ionically conducting, deep eutectic solvent based on acetamide, urea and gallium nitrate is reported for the electrodeposition of gallium nitride/gallium indium nitride under ambient conditions; blue and white light emitting photoluminescent deposits are obtained under potential control.

  17. Efeito da temperatura ambiental na densidade e ponto de congelamento do leite de cabra Effects of ambiental temperature on density and freezing point of goat's milk

    Directory of Open Access Journals (Sweden)

    L.H.A. BRASIL

    1999-12-01

    14 days each one, during the which, the animals under heat stress were exposed to medium air temperature of 33,87ºC, between 8:00 and 17:00 hs including simulated solar radiation from 10:00 to 15:00 hs. On the second week of each experimental interval, individuality milk samples were collected dairy by morning and afternoon, adding preservative. In the end of the week, the samples of each milking were mixed, forming a composed samples which were effected pH, titratable acidity, density and crioscopic point. The results indicated that the obtained values for density and crioscopic point are compatible with the others authors have found it in other countries. It was verified biggers values for the density on the milk milked in the morning, in relation with the afternoon, being that the unequal interval between the milkings could influenced the results. It’s not observed significal statistic differences for this goat milk propriety in termoneutrality and heat stress conditions. To the crioscopic point it not verified statistical difference between the milk milked by morning and afternoon. There was significal statistic difference between the goat milk in termoneutrality and termic stress conditions, being the medium value bigger to the termoneutrality conditions.

  18. A new predictive dynamic model describing the effect of the ambient temperature and the convective heat transfer coefficient on bacterial growth.

    Science.gov (United States)

    Ben Yaghlene, H; Leguerinel, I; Hamdi, M; Mafart, P

    2009-07-31

    In this study, predictive microbiology and food engineering were combined in order to develop a new analytical model predicting the bacterial growth under dynamic temperature conditions. The proposed model associates a simplified primary bacterial growth model without lag, the secondary Ratkowsky "square root" model and a simplified two-parameter heat transfer model regarding an infinite slab. The model takes into consideration the product thickness, its thermal properties, the ambient air temperature, the convective heat transfer coefficient and the growth parameters of the micro organism of concern. For the validation of the overall model, five different combinations of ambient air temperature (ranging from 8 degrees C to 12 degrees C), product thickness (ranging from 1 cm to 6 cm) and convective heat transfer coefficient (ranging from 8 W/(m(2) K) to 60 W/(m(2) K)) were tested during a cooling procedure. Moreover, three different ambient air temperature scenarios assuming alternated cooling and heating stages, drawn from real refrigerated food processes, were tested. General agreement between predicted and observed bacterial growth was obtained and less than 5% of the experimental data fell outside the 95% confidence bands estimated by the bootstrap percentile method, at all the tested conditions. Accordingly, the overall model was successfully validated for isothermal and dynamic refrigeration cycles allowing for temperature dynamic changes at the centre and at the surface of the product. The major impact of the convective heat transfer coefficient and the product thickness on bacterial growth during the product cooling was demonstrated. For instance, the time needed for the same level of bacterial growth to be reached at the product's half thickness was estimated to be 5 and 16.5 h at low and high convection level, respectively. Moreover, simulation results demonstrated that the predicted bacterial growth at the air ambient temperature cannot be assumed to be

  19. Relation of ST-Segment Elevation Myocardial Infarction to Daily Ambient Temperature and Air Pollutant Levels in a Japanese Nationwide Percutaneous Coronary Intervention Registry.

    Science.gov (United States)

    Yamaji, Kyohei; Kohsaka, Shun; Morimoto, Takeshi; Fujii, Kenshi; Amano, Tetsuya; Uemura, Shiro; Akasaka, Takashi; Kadota, Kazushige; Nakamura, Masato; Kimura, Takeshi

    2017-03-15

    Effects of daily fluctuation of ambient temperature and concentrations of air pollutants on acute cardiovascular events have not been well studied. From January 2011 to December 2012, a total of 56,863 consecutive ST-segment elevation myocardial infarction (STEMI) patients who underwent primary percutaneous coronary intervention were registered from 929 institutes with median interinstitutional distance of 2.6 km. We constructed generalized linear mixed models in which the presence or absence of patients with STEMI per day per institute was included as a binomial response variable, with daily meteorologic and environmental data obtained from their respective observatories nearest to the institutes (median distance of 9.7 and 5.6 km) as the explanatory variables. Both lower mean temperature and increase in maximum temperature from the previous day were independently associated with the STEMI occurrence throughout the year (odds ratio [OR] 0.925, 95% confidence interval [CI] 0.915 to 0.935, per 10°C, p variables. Both the absolute value and relative change in the ambient temperature were associated with the occurrence of STEMI; the associations with the air pollutant levels were less clear after adjustment for these meteorologic variables in Japan.

  20. Ambient Space and Ambient Sensation

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    The ambient is the aesthetic production of the sensation of being surrounded. As a concept, 'ambient' is mostly used in relation to the music genre 'ambient music' and Brian Eno's idea of environmental background music. However, the production of ambient sensations must be regarded as a central...... aspect of the aesthetization of modern culture in general, from architecture, transport and urbanized lifeforms to film, sound art, installation art and digital environments. This presentation will discuss the key aspects of ambient aesthetization, including issues such as objectlessness...

  1. Research on Ambient Adaptability of Temperature Measuring Device for Oil-Immersed Transformer%油浸变压器测温装置的环境适应性研究

    Institute of Scientific and Technical Information of China (English)

    戴缘生; 陕华平; 童在林; 李文

    2012-01-01

    The influencing mechanism of ambient temperature of oil surface thermometer is researched. The method to discern influence degree of ambient temperature of thermometer is presented.%研究了油面温度计的环境温度变化影响机理,提出了一套有效鉴别温度计环境温度影响量水平的方法。

  2. Effect of different levels of alpha tocopherol on performance traits, serum antioxidant enzymes, and trace elements in Japanese quail ( Coturnix coturnix japonica under low ambient temperature

    Directory of Open Access Journals (Sweden)

    Assar Ali Shah

    Full Text Available ABSTRACT This study was designed to find the effect of vitamin E supplementation on growth, serum antioxidant enzymes, and some trace elements in Japanese quail (Coturnix coturnix japonica under low ambient temperature. A total of 180 day-old Japanese quails were randomly divided into four groups and provided with 0 (group A, 50 (group B, 100 (group C, and 150 IU/kg (group D vitamin E (dl-α-tocopherol acetate under an average temperature of 9±0.5 °C for an experimental period of 42 days. The result showed that feed intake per day, body weight, weight gain per day, and feed conversion ratio did not differ significantly between the groups. Serum concentrations of superoxide and glutathione peroxidase were significantly high in birds supplemented with 150 mg/kg of vitamin E. The concentration of aspartate aminotransferase was not significantly affected between the control and treated groups; however, alanine transaminase concentration significantly reduced in group D. Zinc concentration in the blood increased significantly in group D, with no significant effect on copper and manganese between the control and treated groups. Vitamin E at the level of 150 IU/kg of feed improves the blood antioxidant status and zinc concentration, with no effect on the performance traits of quail reared under low ambient temperature.

  3. Fuel Maps for the GEP 6.5LT Engine When Operating on at J/JP-8 Fuel Blends at Ambient and Elevated Temperatures

    Science.gov (United States)

    2015-04-01

    77° +/- 4°F 120° +/- 4°F Fuel Inlet Temp 86° +/- 4°F 145° +/- 4°F Engine Coolant Temp 205° +/- 4°F 218 ° +/- 4°F The statement of work indicated a...UNCLASSIFIED UNCLASSIFIED FUEL MAPS FOR THE GEP 6.5LT ENGINE WHEN OPERATING ON ATJ/JP-8 FUEL BLENDS AT AMBIENT AND ELEVATED TEMPERATURES...UNCLASSIFIED Disclaimers Reference herein to any specific commercial company, product, process, or service by trade name, trademark, manufacturer , or

  4. EPISTEMOLOGIA AMBIENTAL

    OpenAIRE

    2012-01-01

    O livro Epistemologia Ambiental traz uma rica discussão sobre a questão ambiental, abordando teorias relevantes para o entendimento e interpretação da crise atual, orientando para a construção de novas racionalidades e a constituição de um saber ambiental. A obra vem compartimentada em cinco capítulos distribuídos em 240 páginas. 

  5. Effect of different arbuscular mycorrhizal fungi on growth and physiology of maize at ambient and low temperature regimes

    DEFF Research Database (Denmark)

    Chen, Xiaoying; Song, Fengbin; Liu, Fulai;

    2014-01-01

    and soluble sugar contents under low temperature condition. The activities of catalase (CAT) and peroxidase of AM inoculated maize were higher than those of non-AM ones. Low temperature noticeably decreased the activities of CAT. The results suggest that low temperature adversely affects maize physiology...

  6. Effect of daily fluctuations in ambient temperature on reproductive failure traits of Landrace and Yorkshire sows under Thai tropical environmental conditions.

    Science.gov (United States)

    Jaichansukkit, Teerapong; Suwanasopee, Thanathip; Koonawootrittriron, Skorn; Tummaruk, Padet; Elzo, Mauricio A

    2017-03-01

    The aim of this study was to determine the effects of daily ranges and maximum ambient temperatures, and other risk factors on reproductive failure of Landrace (L) and Yorkshire (Y) sows under an open-house system in Thailand. Daily ambient temperatures were added to information on 35,579 litters from 5929 L sows and 1057 Y sows from three commercial herds. The average daily temperature ranges (ADT) and the average daily maximum temperatures (PEAK) in three gestation periods from the 35th day of gestation to parturition were classified. The considered reproductive failure traits were the occurrences of mummified fetuses (MM), stillborn piglets (STB), and piglet death losses (PDL) and an indicator trait for number of piglets born alive below the population mean (LBA). A multiple logistic regression model included farrowing herd-year-season (HYS), breed group of sow (BG), parity group (PAR), number of total piglets born (NTB), ADT1, ADT2, ADT3, PEAK1, PEAK2, and PEAK3 as fixed effects, while random effects were animal, repeated observations, and residual. Yorkshire sows had a higher occurrence of LBA than L sows (P = 0.01). The second to fifth parities sows had lower reproductive failures than other parities. The NTB regression coefficients of log-odds were positive (P < 0.01) for all traits. Narrower ranges of ADT3 increased the occurrence of MM, STB, and PDL (P < 0.01), while higher PEAK3 increased the occurrence of MM, STB, PDL, and LBA (P < 0.001). To reduce the risk of reproductive failures, particularly late in gestation, producers would need to closely monitor their temperature management strategies.

  7. The effects of ambient temperature and mixing time of glass ionomer cement material on the survival rate of proximal ART restorations in primary molars

    Directory of Open Access Journals (Sweden)

    Arthur M Kemoli

    2014-01-01

    Full Text Available Objective: Temperature fluctuations and material mixing times are likely to affect the consistency and integrity of the material mixture, and hence the restoration made out of it. The purpose of the present study was to determine the influence of the ambient temperature and the mixing time of glass ionomer cement (GIC restorative material on the survival rate of proximal atraumatic restorative treatment (ART restorations placed in primary molars. Materials and Methods: A total of 804 restorations were placed in the primary molars of 6-8-year-olds using the ART approach. The restorations were then followed for a period of 2 years and evaluated at given intervals. The data collected were analyzed using SPSS computer statistical program, and the results tested and compared using the Chi-square, Kaplan Meier survival analysis and Cox Proportional hazard statistical tests. Results: The cumulative survival rate of the restorations dropped from the initial 94.4% to 30.8% at the end of 2 years. The higher survival rate of the restorations was associated with the experienced operators and assistants when using the rubber dam isolation method. However, there was no statistically significant difference in the survival rate of the restorations when related to the room temperature and the mixing time of the GIC materials used in spite of the variations in the temperature recoded and the methods used in mixing the materials. Conclusion: The ambient temperature and mixing time of GIC did not have a significant effect on the survival of the proximal ART restorations.

  8. Influência da temperatura na solubilidade de beta-caroteno em solventes orgânicos à pressão ambiente Effect of temperature on the solubility of beta-carotene in organic solvents under ambient pressure

    Directory of Open Access Journals (Sweden)

    Marcus Vinícius Três

    2007-12-01

    Full Text Available O presente trabalho reporta dados experimentais de solubilidade em pressão ambiente de beta-caroteno em solventes orgânicos puros (etanol, acetona, acetato de etila e diclorometano e em misturas de tais solventes no intervalo de temperatura de 10 a 60 °C. Para este fim, adotou-se o método gravimétrico para a determinação da solubilidade, utilizando células encamisadas de equilíbrio. Os resultados mostraram que valores mais elevados de solubilidade são obtidos quando foram empregados solventes com parâmetros de solubilidade mais próximos daquele do soluto. Verificou-se que o aumento da temperatura, tanto para solventes puros, como para as misturas de solventes, acarretou num aumento da solubilidade do beta-caroteno para todas as condições experimentais. Observou-se ainda, que nas condições experimentais investigadas, não houve sinergismo significativo para as misturas de solventes quando comparadas aos valores de solubilidade obtidos para os solventes puros. O modelo UNIFAC se mostrou útil na previsão qualitativa dos resultados de solubilidade.This work reports experimental data of the solubility of beta-carotene in pure acetone, ethyl acetate, ethanol and dichloromethane and in mixtures of these organic solvents in the temperature range of 10 to 60 °C under ambient pressure. The gravimetric method was employed to determine the solubility, using glass equilibrium cells. The results showed that the best solvents were those having solubility parameter values close to that of the solute. It was found that raising the temperature caused the solute solubility values for both pure and solvent mixtures to increase under all the experimental conditions. Moreover, no synergetic effects were observed on the solubility of beta-carotene in solvent mixtures compared to pure solvents in the temperature range investigated. The UNIFAC model proved to be useful in predicting the solubility data.

  9. Det ambiente

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    Om begrebet "det ambiente", der beskriver, hvad der sker, når vi fornemmer baggrundsmusikkens diskrete beats, betragter udsigten gennem panoramavinduet eller tager 3D-brillerne på og læner os tilbage i biografsædet. Bogen analyserer, hvorfan ambiente oplevelser skabes, og hvilke konsekvenser det...

  10. Ambient Sensors

    NARCIS (Netherlands)

    Börner, Dirk; Specht, Marcus

    2014-01-01

    This software sketches comprise two custom-built ambient sensors, i.e. a noise and a movement sensor. Both sensors measure an ambient value and process the values to a color gradient (green > yellow > red). The sensors were built using the Processing 1.5.1 development environment. Available under th

  11. Derecho Ambiental

    OpenAIRE

    2014-01-01

    Es indudable la relevancia para la vida del planeta proteger el ambiente. De ahí que a lo largo de las últimas decadas el derecho ambiental se ha consolidado como una nueva y vital rama del derecho público.

  12. Design and development of an ambient-temperature continuously-rotating achromatic half-wave plate for CMB polarization modulation on the POLARBEAR-2 experiment

    Science.gov (United States)

    Hill, Charles A.; Beckman, Shawn; Chinone, Yuji; Goeckner-Wald, Neil; Hazumi, Masashi; Keating, Brian; Kusaka, Akito; Lee, Adrian T.; Matsuda, Frederick; Plambeck, Richard; Suzuki, Aritoki; Takakura, Satoru

    2016-07-01

    We describe the development of an ambient-temperature continuously-rotating half-wave plate (HWP) for study of the Cosmic Microwave Background (CMB) polarization by the POLARBEAR-2 (PB2) experiment. Rapid polarization modulation suppresses 1/f noise due to unpolarized atmospheric turbulence and improves sensitivity to degree-angular-scale CMB fluctuations where the inflationary gravitational wave signal is thought to exist. A HWP modulator rotates the input polarization signal and therefore allows a single polarimeter to measure both linear polarization states, eliminating systematic errors associated with differencing of orthogonal detectors. PB2 projects a 365-mm-diameter focal plane of 7,588 dichroic, 95/150 GHz transition-edge-sensor bolometers onto a 4-degree field of view that scans the sky at 1 degree per second. We find that a 500-mm-diameter ambient-temperature sapphire achromatic HWP rotating at 2 Hz is a suitable polarization modulator for PB2. We present the design considerations for the PB2 HWP, the construction of the HWP optical stack and rotation mechanism, and the performance of the fully-assembled HWP instrument. We conclude with a discussion of HWP polarization modulation for future Simons Array receivers.

  13. Design and development of an ambient-temperature continuously-rotating achromatic half-wave plate for CMB polarization modulation on the POLARBEAR-2 experiment

    CERN Document Server

    Hill, Charles A; Chinone, Yuji; Goeckner-Wald, Neil; Hazumi, Masashi; Keating, Brian; Kusaka, Akito; Lee, Adrian T; Matsuda, Frederick; Plambeck, Richard; Suzuki, Aritoki; Takakura, Satoru

    2016-01-01

    We describe the development of an ambient-temperature continuously-rotating half-wave plate (HWP) for study of the Cosmic Microwave Background (CMB) polarization by the POLARBEAR-2 (PB2) experiment. Rapid polarization modulation suppresses 1/f noise due to unpolarized atmospheric turbulence and improves sensitivity to degree-angular-scale CMB fluctuations where the inflationary gravitational wave signal is thought to exist. A HWP modulator rotates the input polarization signal and therefore allows a single polarimeter to measure both linear polarization states, eliminating systematic errors associated with differencing of orthogonal detectors. PB2 projects a 365-mm-diameter focal plane of 7,588 dichroic, 95/150 GHz transition-edge-sensor bolometers onto a 4-degree field of view that scans the sky at $\\sim$ 1 degree per second. We find that a 500-mm-diameter ambient-temperature sapphire achromatic HWP rotating at 2 Hz is a suitable polarization modulator for PB2. We present the design considerations for the PB...

  14. Ambient Dried Aerogels

    Science.gov (United States)

    Jones, Steven M.; Paik, Jong-Ah

    2013-01-01

    A method has been developed for creating aerogel using normal pressure and ambient temperatures. All spacecraft, satellites, and landers require the use of thermal insulation due to the extreme environments encountered in space and on extraterrestrial bodies. Ambient dried aerogels introduce the possibility of using aerogel as thermal insulation in a wide variety of instances where supercritically dried aerogels cannot be used. More specifically, thermoelectric devices can use ambient dried aerogel, where the advantages are in situ production using the cast-in ability of an aerogel. Previously, aerogels required supercritical conditions (high temperature and high pressure) to be dried. Ambient dried aerogels can be dried at room temperature and pressure. This allows many materials, such as plastics and certain metal alloys that cannot survive supercritical conditions, to be directly immersed in liquid aerogel precursor and then encapsulated in the final, dried aerogel. Additionally, the metalized Mylar films that could not survive the previous methods of making aerogels can survive the ambient drying technique, thus making multilayer insulation (MLI) materials possible. This results in lighter insulation material as well. Because this innovation does not require high-temperature or high-pressure drying, ambient dried aerogels are much less expensive to produce. The equipment needed to conduct supercritical drying costs many tens of thousands of dollars, and has associated running expenses for power, pressurized gasses, and maintenance. The ambient drying process also expands the size of the pieces of aerogel that can be made because a high-temperature, high-pressure system typically has internal dimensions of up to 30 cm in diameter and 60 cm in height. In the case of this innovation, the only limitation on the size of the aerogels produced would be in the ability of the solvent in the wet gel to escape from the gel network.

  15. Neutral gas temperature maps of the pin-to-plate Argon micro discharge into the ambient air

    CERN Document Server

    Xu, Shaofeng; Majeed, Asif

    2015-01-01

    This study is designed to explore the two dimensional temperature maps of the atmospheric argon discharge consisting of pin-to-plane electrodes supplied by a high voltage DC source. After checking the stability of the micro discharge, the two dimensional image plane focused by a quartz lens was scanned by the fiber probe driven by a 3D Mobile Platform. The rotational and vibrational temperatures are calculated using nitrogen emissions collected by the high resolution spectrometer and high sensitive intensified charge coupled device (ICCD). The rotational temperature varies from 1558.15 K to 2621.14 K and vibrational temperature varies from 3010.38 K to 3774.69 K, indicating a great temperature gradient due to small discharge size. The temperature maps show a lateral expansion and a sharp truncation in the radial direction. A double layers discharge is identified, where an arc discharge coats the glow discharge.

  16. Tensile behavior of a 2D woven C/SiC composite at ambient and elevated temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Camus, G.; Barbier, J.E. [Laboratorie des Composites Thermostructuraux, Pessac (France)

    1995-12-01

    A 2D reinforced composite of carbon fibers in a SiC-CVI processed matrix was tested under monotonic tension at various temperatures ranging from room temperature to 1600{degrees}C in an inert atmosphere. Up to 1000{degrees}C, the mechanical behavior remained elastic-damageable and changes proved to be essentially governed by the progressive vanishing of the processing-related thermal residual stresses. Beyond this temperature, irreversible residual strains (i.e. unrecovered upon compression) were observed whereas the tensile behavior became increasingly time-temperature dependent. The mechanisms responsible for such a behavior are reported and discussed.

  17. EFFECT OF PRE-TREATMENTS ON PHYSICO-CHEMICAL COMPOSITION OF DEHYDRATED JACKFRUIT CHIPS DURING STORAGE AT AMBIENT TEMPERATURE

    Directory of Open Access Journals (Sweden)

    ROHAN R. PATIL, MANDAR KHANVILKAR, D. N. MOKAT*, P. P. RELEKAR AND R K. H. PUJARI

    2014-08-01

    The dehydrated chips of jackfruit pre-treated with ascorbic acid (T4 recorded maximum mean score for colour, flavour and texture irrespective of storage period. The organoleptic scores of these dehydrated jackfruit chips for all above attributes were declined with the increase in storage period from 0 to 60 days. The dehydrated chips pre-treated with ascorbic acid (T4 recorded maximum overall acceptability score of 6.91 at 60 days of storage which clearly indicated its suitability for making good quality chips and also for storing them for 60 days at ambient conditions without much loss of sensory and nutritional qualities of chips.Keywords: Physico chemical composition of dehydrated chips of jackfruit (Artocarpus heterophyllus and storage period.

  18. Thermal degradation of concrete in the temperature range from ambient to 315{degree} C (600{degree} F). Revision 10/96

    Energy Technology Data Exchange (ETDEWEB)

    Kassir, M.K.; Bandyopadhyay, K.K.; Reich, M.

    1996-10-01

    This report is concerned with determining the effect of elevated temperatures on the behavior of concrete. Emphasis is placed on quantifying the degree of potential degradation of the physical properties of concrete in high-level waste storage tanks. The temperature elevation range of interest is from ambient to 315 C (600 F). The literature has been reviewed to examine the applicable experimental data and quantify the degradation in the concrete and reinforcing steel. Since many variables and test conditions control the results in the data base, upper and lower bounds of the degraded properties at temperatures applicable to the environments of the storage tanks are summarized and presented in explicit forms. For properties with large data bases, a normal logarithmic distribution of the data is assumed and a statistical analysis is carried out to find the mean and 84% values of the degraded property in the temperature range of interest. Such results are useful in assessing the effect of elevated temperatures on the structural behavior of the tanks. In addition, the results provide the technical basis for a parametric study that may be necessary to investigate the thermal aspects of the structural integrity of the tanks. 50 refs., 23 figs.

  19. Online Estimation of Model Parameters and State of Charge of LiFePO4 Batteries Using a Novel Open-Circuit Voltage at Various Ambient Temperatures

    Directory of Open Access Journals (Sweden)

    Fei Feng

    2015-04-01

    Full Text Available This study describes an online estimation of the model parameters and state of charge (SOC of lithium iron phosphate batteries in electric vehicles. A widely used SOC estimator is based on the dynamic battery model with predeterminate parameters. However, model parameter variances that follow with their varied operation temperatures can result in errors in estimating battery SOC. To address this problem, a battery online parameter estimator is presented based on an equivalent circuit model using an adaptive joint extended Kalman filter algorithm. Simulations based on actual data are established to verify accuracy and stability in the regression of model parameters. Experiments are also performed to prove that the proposed estimator exhibits good reliability and adaptability under different loading profiles with various temperatures. In addition, open-circuit voltage (OCV is used to estimate SOC in the proposed algorithm. However, the OCV based on the proposed online identification includes a part of concentration polarization and hysteresis, which is defined as parametric identification-based OCV (OCVPI. Considering the temperature factor, a novel OCV–SOC relationship map is established by using OCVPI under various temperatures. Finally, a validating experiment is conducted based on the consecutive loading profiles. Results indicate that our method is effective and adaptable when a battery operates at different ambient temperatures.

  20. Det Ambiente

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    Det ambiente er iscenesættelsen af en karakteristisk sanseoplevelse, der er kendetegnet ved fornemmelsen af at være omgivet. I dag bliver begrebet om det ambiente mest anvendt i forbindelse med musikgenren ’ambient musik’. Det ambiente er dog ikke essentielt knyttet til det musikalske, men må...... forstås som et betydeligt bredere fænomen i den moderne æstetiske kultur, der spiller en væsentlig rolle i oplevelsen af moderne transportformer, arkitektur, film, lydkunst, installationskunst og digitale multimedieiscenesættelser. En forståelse af det ambiente er derfor centralt for forståelsen af en...... moderne æstetiseret oplevelseskultur i almindelighed. Da det ambiente ikke hidtil har været gjort til genstand for en mere indgående teoretisk behandling, er der dog stor usikkerhed omkring, hvad fænomenet overhovedet indebærer. Hovedformålet med Det ambiente – Sansning, medialisering, omgivelse er derfor...

  1. X-ray sensing materials stability: influence of ambient storage temperature on essential thermal properties of undoped vitreous selenium

    Science.gov (United States)

    Tonchev, D.; Mani, H.; Belev, G.; Kostova, I.; Kasap, S.

    2014-12-01

    Amorphous selenium (a-Se) is currently used in x-ray image detectors as an x-ray photoconductor. Normally a-Se films used in device applications are fabricated by the evaporation of vitreous bulk material loaded into boats in a typical vacuum deposition system. The resistance against crystallization is an important factor in both film and bulk forms of a-Se. Previous work has indicted that the resistance to crystallization is surprisingly more pronounced around 35 °C [1]. In this work we have therefore examined the essential thermal properties of vitreous selenium (99.999%) samples that have been stored at different temperatures. The thermal characterization experiments involved a series of DSC (Differential Scanning Calorimetry) measurements in which have monitored the glass transition and melting endotherms, and the crystallization exotherm in heating-cooling-heating scans. In DSC experiments, a sample would be heated to a temperature above the melting temperature, equilibrated, then cooled at a fixed rate down to 20 °C, then equilibrated and finally scanned again under a heating schedule. The samples were isothermally stored at temperatures corresponding to 18, 35 and 55 °C. The thermal analysis results show that there are distinct differences in the thermal properties. We have examined the stability in terms of the difference in the crystallization onset temperature (Tc) and the onset of glass transition temperature (Tg). We also examined the Hruby coefficient (Kgl) of these samples, that is Kgl = (Tc - Tg)/(Tm - Tc) where Tc is the crystallization onset temperature and Tm is the melting onset temperature. We have found Kgl to depend on the storage temperature. Surprisingly, we observed that the Hruby coefficient is actually larger at 35 °C compared to the values at 18 and 55 °C.

  2. The effect of irradiation temperatures between ambient and 80 deg. C on the response of alanine dosimeters

    DEFF Research Database (Denmark)

    Sharpe, P.H.G.; Miller, Arne; Sephton, J.P.;

    2009-01-01

    Published data on the effect of irradiation temperature on the response of alanine dosimeters does not extend to the temperatures that may be experienced in high-dose industrial irradiations, particularly in the case of electron beams. We describe here results of the irradiation of alanine...... begins to deviate significantly from linearity and shows marked dose dependence. The effect of this behaviour under conditions typically experienced in industrial processing is evaluated and recommendations made concerning the use of alanine dosimeters at high doses and temperatures....

  3. DOE STI Product/Final Report Number 3 Electrochemical Investigation of Novel Electrolytes for Ambient Temperature Sodium Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ketack; Lang, Christopher M.; Doyle, Kevin; Kohl, Paul A.

    2005-12-01

    The need for low-cost, high-energy density, durable, secondary batteries continues to rise with the demands of the electronics and automobile industries. A room-temperature version of the (high-temperature) ''Zebra Cell'' may provide an interesting technology for portable electronics and transportation. Sodium-based batteries have received attention as an alternative to the lithium-based batteries due to several factors including the absence of dendrite formation during sodium deposition and the abundance of sodium. This work focused on (1) the development of room-temperature ionic liquids (IL) for use in electrochemical devices, including batteries, (2) development and evaluation of secondary sodium batteries using room-temperature ILs, and (3) advancing the fundamental understanding of the electrochemical processes involving ILs and battery technology. Several objectives were accomplished during this program.

  4. Response of branchial Na(+)/K(+) ATPase to changes in ambient temperature in Atlantic cod (Gadus morhua) and whiting (Merlangius merlangus).

    Science.gov (United States)

    Michael, Katharina; Koschnick, Nils; Pörtner, Hans-O; Lucassen, Magnus

    2016-05-01

    The maintenance of ion and pH homeostasis despite changes in ambient temperature is crucial for ectothermic organisms. Thermal sensitivity of Na(+)/K(+) ATPase mRNA expression, protein expression and activity was determined in gills of North Sea cod (NC) and Northeastern Arctic cod (NEAC), acclimated for 6 weeks at 4 and 10 °C and compared to field samples of North Sea cod (sNC), acclimatized to early spring (4 °C) and summer (18 °C) conditions. The same analyses were conducted in gills of the confamiliar whiting, acclimated at 4 and 10 °C. Branchial Na(+)/K(+) ATPase capacities remained uncompensated at functional and protein levels in NC and NEAC at both acclimation temperatures. Na(+)/K(+) ATPase mRNA expression in NEAC acclimated at 10 °C was about twofold higher compared to NC, indicating some population-specific differentiation at this level. Lower Na(+)/K(+) ATPase capacities in gills of warm-acclimatized sNC at common assay temperatures indicate thermal compensation between seasonal extremes, and post-translational modifications contributed to this mitigation at high assay temperature. Together, cod compensates Na(+)/K(+) ATPase capacities on the warm edge of the thermal window and below 4 °C, respectively. In contrast, whiting Na(+)/K(+) ATPase capacities were cold compensated at 4 °C, supported by 1.5-fold higher mRNA and protein expression. Besides, capacities were lower in whiting compared to NC and NEAC at optimum temperature, which may be advantageous in terms of reduced maintenance cost, but at temperatures ≤4 °C, compensation may represent an energy trade-off to maintain homeostasis. The species-specific response of gadid Na(+)/K(+) ATPase indicates certain threshold temperatures beyond which compensation of the pump is elicited, possibly related to the different biogeography of these species.

  5. Changes in ambient temperature and oxygenation during the proestrus do not affect duration, regularity and repeatability of the estrus cycle in female rats.

    Directory of Open Access Journals (Sweden)

    Grazyna Wójcik

    2009-12-01

    Full Text Available There are a lot of factors affecting the release of hormones from the anterior part of pituitary gland and their interactions with other parts of the endocrine, nervous and immune systems. The special significance of the proestrus phase of the estrous cycle of the rat, during which LH and FSH levels increase, followed by ovulation is known. The short length of the estrous cycle and the well recognized sequence of vaginal lavage cytology make it useful for investigating the influence of a stressful environment on the reproductive function. Short duration and mild changes in environmental conditions is considered as a factor analogous to psychological stress. The study was undertaken to determine the effects of a short duration change in the ambient temperature and oxygenation (30 minutes on the proestrus phase of reproductive cycle and on the repeatability and regularity of phases of the reproductive cycle of Wistar strain rats. The animals were kept under standard conditions and had food and water available ad libitum. The climatic chamber with automatically adjustable and monitored internal parameters (temperature, oxygenation, humidity was used to develop stress conditions. An estimation of the vaginal lavage using the microscope was done to determine the estrous cycle. The animals were divided into 6 groups. On the day of experiment: the control group (CG stayed in the climatic chamber for 30 minutes (ambient temperature 21 degrees C, normoxia - 21% O(2, the five test groups (TG - I - V remained in the climatic chamber for 30 minutes, in the established environmental conditions (I - 21 degrees C, 10% O(2; II - 10 degrees C, 21% O(2; III - 10 degrees C, 10% O(2; IV - 35 degrees C, 21% O(2; V - 35 degrees C, 10% O(2. During the following days after the experiment, a microscopic estimation of vaginal lavage was collected over again. There were no changes of duration and sequence of the present estrous cycle and repeatability of the next cycles

  6. Axial- and radial-resolved electron density and excitation temperature of aluminum plasma induced by nanosecond laser: Effect of the ambient gas composition and pressure

    Directory of Open Access Journals (Sweden)

    Mahmoud S. Dawood

    2015-11-01

    Full Text Available The spatial variation of the characteristics of an aluminum plasma induced by a pulsed nanosecond XeCl laser is studied in this paper. The electron density and the excitation temperature are deduced from time- and space- resolved Stark broadening of an ion line and from a Boltzmann diagram, respectively. The influence of the gas pressure (from vacuum up to atmospheric pressure and compositions (argon, nitrogen and helium on these characteristics is investigated. It is observed that the highest electron density occurs near the laser spot and decreases by moving away both from the target surface and from the plume center to its edge. The electron density increases with the gas pressure, the highest values being occurred at atmospheric pressure when the ambient gas has the highest mass, i.e. in argon. The excitation temperature is determined from the Boltzmann plot of line intensities of iron impurities present in the aluminum target. The highest temperature is observed close to the laser spot location for argon at atmospheric pressure. It decreases by moving away from the target surface in the axial direction. However, no significant variation of temperature occurs along the radial direction. The differences observed between the axial and radial direction are mainly due to the different plasma kinetics in both directions.

  7. On the Effect of Carbon Content to the Mechanical Properties and Microstructure of Green Compacts Formed at above Ambient Temperature

    Directory of Open Access Journals (Sweden)

    Md. Mujibur Rahman

    2011-01-01

    Full Text Available Friction force is generated during the generation of green compacts from metal powder, which obviously gives adverse effect to the mechanical properties and microstructure of the green compacts. In this study, fine carbon powder is used to minimize the interparticle as well as die wall frictions and as alloying element hence high density yet defect-free near-net shape or net shape mechanical components can be produced. Powder forming at elevated temperature is a relatively new technology hence the effect of carbon content is not fully explored yet. Therefore, a lab scale warm compaction rig is designed and fabricated which enabled the generation of green compacts at different forming load and temperature. The powder mass was prepared by mechanically mixing iron ASC 100.29 powder with different weight percent of fine carbon powder for different duration of time. The prepared powder mass was formed at different compaction temperature to generate green compacts for the purpose of mechanical testing and microstructure evaluation. The results revealed that the mechanical properties and microstructures of green compacts are affected by the carbon content, mixing time, as well as forming temperature. From this study, the suitable carbon content, mixing time, and forming temperature are identified for the production of high quality mechanical components.

  8. Cross-sensitivity of metal oxide gas sensor to ambient temperature and humidity: Effects on gas distribution mapping

    Science.gov (United States)

    Kamarudin, K.; Bennetts, V. H.; Mamduh, S. M.; Visvanathan, R.; Yeon, A. S. A.; Shakaff, A. Y. M.; Zakaria, A.; Abdullah, A. H.; Kamarudin, L. M.

    2017-03-01

    Metal oxide gas sensors have been widely used in robotics application to perform remote and mobile gas sensing. However, previous researches have indicated that this type of sensor technology is cross-sensitive to environmental temperature and humidity. This paper therefore investigates the effects of these two factors towards gas distribution mapping and gas source localization domains. A mobile robot equipped with TGS2600 gas sensor was deployed to build gas distribution maps of indoor environment, where the temperature and humidity varies. The results from the trials in environment with and without gas source indicated that there is a strong relation between the fluctuation of the mean and variance map with respect to the variations in the temperature and humidity maps.

  9. Modulation of ambient temperature promotes inflammation and initiates atherosclerosis in wild type C57BL/6 mice

    Directory of Open Access Journals (Sweden)

    Daniel A. Giles

    2016-11-01

    Conclusions: In sum, our novel data in WT C57Bl/6 mice suggest that modulation of a single environmental variable, temperature, dramatically alters mouse physiology, metabolism, and inflammation, allowing for an improved mouse model of atherosclerosis. Thus, thermoneutral housing of mice shows promise in yielding a better understanding of the cellular and molecular pathways underlying the pathogenesis of diverse diseases.

  10. High-T(sub c) Superconductor-Normal-Superconductor Junctions with Polyimide-Passivated Ambient Temperature Edge Formation

    Science.gov (United States)

    Barner, J. B.; Kleinsasser, A. W.; Hunt, B. D.

    1996-01-01

    The ability to controllably fabricate High-Temperature Superconductor (HTS) S-Normal-S (SNS) Josephson Juntions (JJ's) enhances the possibilities fro many applications, including digital circuits, SQUID's, and mixers. A wide variety of approaches to fabricating SNS-like junctions has been tried and analyzed in terms of proximity effect behavior.

  11. Effects of relative humidity and ambient temperature on the ballistic delivery of micro-particles to excised porcine skin.

    Science.gov (United States)

    Kendall, Mark; Rishworth, Stephen; Carter, Fiona; Mitchell, Thomas

    2004-03-01

    The effectiveness of ballistic particle delivery to the skin is often dependent upon breaching the stratum corneum (SC) and targeting cells within defined layers of the viable epidermis. This paper experimentally determines the influence of relative humidity (RH) and temperature on the ballistic delivery of particles to the skin. Gold particles of radius 0.9+/-0.6 microm were accelerated by a hand-held supersonic device to impact freshly excised porcine skin at 410-665 m per s. Increasing the RH from 15% to 95% (temperature at 25 degrees C) led to a particle penetration increase by a factor of 1.8. Temperature increases from 20 degrees C to 40 degrees C (RH at 15%) enhanced particle penetration 2-fold. In both cases, these increases were sufficient to move the target layer from the SC to the viable epidermis. Relative trends in particle penetration compared well with predictions from a theoretical model well. Calculated absolute penetration depths are 6-fold greater than the measurements. The inversely calculated dynamic yield stress of the SC is up to a factor of 10 higher than reported quasi-static measurements, due to changes in tissue failure modes over a strain-rate range spanning 10 orders of magnitude. If targeted particle delivery is required, it is recommended that the environmental RH and temperature be monitored.

  12. The Combined Effect of High Ambient Temperature and Antihypertensive Treatment on Renal Function in Hospitalized Elderly Patients

    Science.gov (United States)

    Novack, Victor; Rogachev, Boris; Haviv, Yosef S.; Barski, Leonid

    2016-01-01

    Background The aging kidney manifests structural, functional as well as pharmacological changes, rendering elderly patients more susceptible to adverse environmental influences on their health, dehydration in particular. Hypothesis Higher temperature is associated with renal function impairment in patients 65 years and older who routinely take thiazide and/or ACE-inhibitors/ARBs. Methods We obtained health data of patients older than 65 who were admitted to a large tertiary center during the years 2006–2011, with a previous diagnosis of hypertension, and treated with thiazide, ACE-inhibitors/ARBs or both. We collected environmental data of daily temperature, available from collaborative public and governmental institutions. In order to estimate the effect of daily temperature on renal function we performed linear mixed models, separately for each treatment group and creatinine change during hospital admission. Results We identified 26,286 admissions for 14, 268 patients with a mean age of 75.6 (±6.9) years, of whom 53.6% were men. Increment in daily temperature on admission of 5°C had significant effect on creatinine increase in the no treatment (baseline creatinine adjusted 0.824 mg/dL, % change 1.212, % change 95% C.I 0.082–2.354) and dual treatment groups (baseline creatinine adjusted 1.032mg/dL, % change 3.440, % change 95% C.I 1.227–5.700). Sub-analysis stratified by advanced age, chronic kidney disease and primary diagnosis on hospital admission, revealed a significant association within patients admitted due to acute infection and treated with dual therapy. Conclusion Whereas previous studies analyzed sporadic climate effects during heat waves and/or excluded older population taking anti-hypertensive medications, the present study is novel by showing a durable association of temperature and decreased renal function specifically in elderly patients taking anti-hypertensive medications. PMID:27992525

  13. Experimental Study of Ambient Air Temperature Effects on The Performance of a General Vapor-Compression Refrigeration Cycle

    Directory of Open Access Journals (Sweden)

    Ayad T. Mustafa

    2013-05-01

    Full Text Available         In this work an experimental study for the vapor – compression refrigeration cycle has been performed under temperature range of  9.7-32°C. The effect of      varying temperature on heat exchangers pressures, cooling capacity, net power consumption, and coefficient of performance COP are studied .                                   The results indicated that condenser pressure, evaporator pressure, and power consumption increased with the increase of temperature. The data also indicated that cooling capacity increased as temperature increased until 15.6°C then after it decreased with further temperature increase. Also COP follow the same tread of cooling capacity.                                                                                                              

  14. Periodic usage of low-protein methionine-fortified diets in broiler chickens under high ambient temperature conditions: effects on performance, slaughter traits, leukocyte profiles and antibody response.

    Science.gov (United States)

    Ghasemi, Hossein Ali; Ghasemi, Rohollah; Torki, Mehran

    2014-09-01

    This study was performed to evaluate the effects of adding methionine supplements to low-protein diets and subsequent re-feeding with a normal diet on the productive performance, slaughter parameters, leukocyte profiles and antibody response in broiler chickens reared under heat stress conditions.During the whole experimental period (6-49 days), the birds were raised in battery cages located in high ambient temperature in an open-sided housing system. A total of 360 6-day-old male chickens were divided into six treatments in six replicates with ten chicks each. Six isoenergetic diets, with similar total sulfur amino acids levels, were formulated to provide 100 and 100 (control), 85 and 100 (85S), 70 and 100 (70S), 85 and 85 (85SG), 70 and 85 (70S85G), and 70 and 70% (70SG) of National Research Council recommended levels for crude protein during the starter (6-21 day) and grower (22-42 day) periods, respectively. Subsequently, all groups received a diet containing the same nutrients during the finisher period (43-49 day). The results showed that, under heat stress conditions, average daily gain and feed conversion ratio and performance index from day 6 to 49, breast and thigh yields and antibody titer against Newcastle disease in the birds fed diets 85S, 70S and 85SG were similar to those of birds fed control diet, whereas feeding diets 70S85G and 70SG significantly decreased the values of above-mentioned parameters. Additionally, diets 85S, 70S and 85SG significantly decreased mortality rate and heterophil:lymphocyte ratio compared with the control diet. In conclusion, the results indicate that supplementation of methionine to diets 85S, 70S and 85SG, and then re-feeding with a conventional diet is an effective tool to maintain productive performance and to improve health indices and heat resistance in broilers under high ambient temperature conditions.

  15. Periodic usage of low-protein methionine-fortified diets in broiler chickens under high ambient temperature conditions: effects on performance, slaughter traits, leukocyte profiles and antibody response

    Science.gov (United States)

    Ghasemi, Hossein Ali; Ghasemi, Rohollah; Torki, Mehran

    2014-09-01

    This study was performed to evaluate the effects of adding methionine supplements to low-protein diets and subsequent re-feeding with a normal diet on the productive performance, slaughter parameters, leukocyte profiles and antibody response in broiler chickens reared under heat stress conditions. During the whole experimental period (6-49 days), the birds were raised in battery cages located in high ambient temperature in an open-sided housing system. A total of 360 6-day-old male chickens were divided into six treatments in six replicates with ten chicks each. Six isoenergetic diets, with similar total sulfur amino acids levels, were formulated to provide 100 and 100 (control), 85 and 100 (85S), 70 and 100 (70S), 85 and 85 (85SG), 70 and 85 (70S85G), and 70 and 70 % (70SG) of National Research Council recommended levels for crude protein during the starter (6-21 day) and grower (22-42 day) periods, respectively. Subsequently, all groups received a diet containing the same nutrients during the finisher period (43-49 day). The results showed that, under heat stress conditions, average daily gain and feed conversion ratio and performance index from day 6 to 49, breast and thigh yields and antibody titer against Newcastle disease in the birds fed diets 85S, 70S and 85SG were similar to those of birds fed control diet, whereas feeding diets 70S85G and 70SG significantly decreased the values of above-mentioned parameters. Additionally, diets 85S, 70S and 85SG significantly decreased mortality rate and heterophil:lymphocyte ratio compared with the control diet. In conclusion, the results indicate that supplementation of methionine to diets 85S, 70S and 85SG, and then re-feeding with a conventional diet is an effective tool to maintain productive performance and to improve health indices and heat resistance in broilers under high ambient temperature conditions.

  16. Heat effects of ambient apparent temperature on all-cause mortality in Cape Town, Durban and Johannesburg, South Africa: 2006-2010.

    Science.gov (United States)

    Wichmann, Janine

    2017-06-01

    Due to climate change, an increase of 3-4°C in ambient temperature is projected along the South African coast and 6-7°C inland during the next 80years. The objective of this study was to investigate the association between daily ambient apparent temperature (Tapp) and daily all-cause non-accidental mortality (hereafter mortality) in Cape Town, Durban and Johannesburg during a 5-year study period (2006-2010). Susceptibility by sex and age groups (Cape Town, Durban and Johannesburg. A 3.3%, 2.6% and 2.8% increase in mortality per IQR increase in Tapp (lag0-1) was observed in Cape Town, Durban and Johannesburg, respectively above the city-specific thresholds. The elderly were more at risk in Cape Town and Johannesburg. No difference in risk was observed for males and females in the three cities. In the meta-analysis an overall significant increase of 0.9% in mortality per 1°C increase in Tapp (lag0-1) was observed for all age groups combined in the three cities. For the ≥65year group a significant increase of 2.1% in mortality was observed. In conclusion, the risks for all age groups combined and the elderly are similar to those reported in studies from developed and developing countries. The results can be used in present-day early warning systems and in risk assessments to estimate the impact of increased Tapp in the country due to climate change. Future research should investigate the association between Tapp and cause-specific mortality and also morbidity.

  17. Increased upper critical field for nanocrystalline MoN thin films deposited on AlN buffered substrates at ambient temperature

    Science.gov (United States)

    Baskaran, R.; Thanikai Arasu, A. V.; Amaladass, E. P.; Vaidhyanathan, L. S.; Baisnab, D. K.

    2016-05-01

    Molybdenum nitride (MoN) thin films have been deposited using reactive DC magnetron sputtering on aluminum nitride buffered oxidized silicon substrates at ambient temperature. GIXRD of aluminum nitride (AlN) deposited under similar conditions has revealed the formation of wurtzite phase AlN. GIXRD characterization of molybdenum thin films deposited on AlN buffered oxidized silicon substrates has indicated the formation of nanocrystalline MoN thin films. The electrical resistivity measurements indicate MoN thin films have a superconducting transition temperature of ~8 K. The minimum transition width of the MoN thin film is 0.05 K at 0 T. The inferred upper critical field B c2(0) for these nanocrystalline MoN thin films obtained by fitting the temperature dependence of critical field with Werthamer, Helfand and Hohenberg theory lies in the range of 17-18 T which is the highest reported in literature for MoN thin films.

  18. On the Effect of Carbon Content to the Mechanical Properties and Microstructure of Green Compacts Formed at above Ambient Temperature

    OpenAIRE

    Md. Mujibur Rahman; Sany Shahriman Md Nor; Hendri Yani Rahman

    2011-01-01

    Friction force is generated during the generation of green compacts from metal powder, which obviously gives adverse effect to the mechanical properties and microstructure of the green compacts. In this study, fine carbon powder is used to minimize the interparticle as well as die wall frictions and as alloying element hence high density yet defect-free near-net shape or net shape mechanical components can be produced. Powder forming at elevated temperature is a relatively new technology henc...

  19. Design and construction of a heat stage for investigations of samples by atomic force microscopy above ambient temperatures

    DEFF Research Database (Denmark)

    Bækmark, Thomas Rosleff; Bjørnholm, Thomas; Mouritsen, Ole G.

    1997-01-01

    The construction from simple and cheap commercially available parts of a miniature heat stage for the direct heating of samples studied with a commercially available optical-lever-detection atomic force microscope is reported. We demonstrate that by using this heat stage, atomic resolution can be...... be obtained on highly oriented pyrolytic graphite at 52 °C. The heat stage is of potential use for the investigation of biological material at physiological temperatures. ©1997 American Institute of Physics....

  20. Modificações nas atividades da poligalacturonase e pectinametilesterase em morangos armazenados a temperatura ambiente Modifications in the activities of poligalacturonase and pectinametilesterase in stored strawberries the ambient temperature

    Directory of Open Access Journals (Sweden)

    Polyanna Alves Silva

    2009-01-01

    Full Text Available Objetivou-se, neste trabalho, avaliar as modificações da poligalacturonase (PG e da pectinametilesterase (PME em morangos cultivados na região de Lavras, MG, e armazenados em temperatura ambiente. Foram utilizados morangos das cultivares 'Oso-grande', 'Toyorrinho' e 'Tudla'. Utilizou-se o delineamento inteiramente casualizado com 4 repetições, sendo os tratamentos arranjados em esquema fatorial (3X2, sendo 3 cultivares e 2 dias de análises (0 e 5 dias. A parcela experimental foi constituída por 10 frutos. Durante o armazenamento houve uma diminuição nos teores de pectina total e um aumento nos de pectina solúvel em todas as variedades analisadas. A atividade da PG e PME aumentaram com o período de armazenamento, independente da cultivar.The objective of this research was to evaluate the modifications of the polygalacturonase (PG and the pectinmethilesterase (PME in strawberries cultivated in the region of Lavras, MG, and stored at room temperature. Strawberries of the research were used for plantation of 'Oso-grande', 'Toyorrinho' and 'Tudla'. The entirely randomized design with 4 replicates was used, being the treatments arranged in factorial (3x2, being 3 plantations and 2 days of analyses (0 and 5 days. The experimental parcel was consisted by 10 fruits. During the storage there was a reduction in the levels of total pectin and an increase in the ones of soluble pectin in all the analyzed varieties. With the period of storage the PG and PME activity grew, independent of the cultivar.

  1. Solid-state ligand-driven light-induced spin change at ambient temperatures in bis(dipyrazolylstyrylpyridine)iron(II) complexes.

    Science.gov (United States)

    Takahashi, Kazuhiro; Hasegawa, Yuta; Sakamoto, Ryota; Nishikawa, Michihiro; Kume, Shoko; Nishibori, Eiji; Nishihara, Hiroshi

    2012-05-07

    We previously reported that an Fe(II) complex ligated by two (Z)-2,6-di(1H-pyrazol-1-yl)-4-styrylpyridine ligands (Z-H) presented a solid state ligand-driven light-induced spin change (LD-LISC) upon one-way Z-to-E photoisomerization, although modulation of the magnetism was trivial at ambient temperatures (Chem. Commun.2011, 47, 6846). Here, we report the synthesis of new derivatives of Z-H, Z-CN and Z-NO(2), in which electron-withdrawing cyano and nitro substituents are introduced at the 4-position of the styryl group to attain a more profound photomagnetism at ambient temperatures. Z-CN and Z-NO(2) undergo quantitative one-way Z-to-E photochromism upon excitation of the charge transfer band both in acetonitrile and in the solid state, similar to the behavior observed for Z-H. In solution, these substituents stabilized the low-spin (LS) states of Z-CN and Z-NO(2), and the behavior was quantitatively analyzed according to the Evans equation. The photomagnetic properties in the solid state, on the other hand, cannot be explained in terms of the substituent effect alone. Z-CN displayed photomagnetic properties almost identical to those of Z-H. Z-CN preferred the high-spin (HS) state at all temperatures tested, whereas photoirradiated Z-CN yielded a lower χ(M)T at ambient temperatures. The behavior of Z-NO(2) was counterintuitive, and the material displayed surprising photomagnetic properties in the solid state. Z-NO(2) occupied the LS state at low temperatures and underwent thermal spin crossover (SCO) with a T(1/2) of about 270 K. The photoirradiated Z-NO(2) displayed a higher value of χ(M)T and the modulation of χ(M)T exceeded that of Z-H or Z-CN. Z-NO(2)·acetone, in which acetone molecules were incorporated into the crystal lattice, further stabilized the LS state (T(1/2) > 300 K), thereby promoting large modulations of the χ(M)T values (87% at 273 K and 64% at 300 K) upon Z-to-E photoisomerization. Single crystal X-ray structure analysis revealed that

  2. Performance of a pilot scale microbial electrolysis cell fed on domestic wastewater at ambient temperatures for a 12 month period.

    Science.gov (United States)

    Heidrich, Elizabeth S; Edwards, Stephen R; Dolfing, Jan; Cotterill, Sarah E; Curtis, Thomas P

    2014-12-01

    A 100-L microbial electrolysis cell (MEC) was operated for a 12-month period fed on raw domestic wastewater at temperatures ranging from 1°C to 22°C, producing an average of 0.6 L/day of hydrogen. Gas production was continuous though decreased with time. An average 48.7% of the electrical energy input was recovered, with a Coulombic efficiency of 41.2%. COD removal was inconsistent and below the standards required. Limitations to the cell design, in particular the poor pumping system and large overpotential account for many of the problems. However these are surmountable hurdles that can be addressed in future cycles of pilot scale research. This research has established that the biological process of an MEC will to work at low temperatures with real wastewater for prolonged periods. Testing and demonstrating the robustness and durability of bioelectrochemical systems far beyond that in any previous study, the prospects for developing MEC at full scale are enhanced.

  3. Effects of ambient temperature on egg and larval development of the invasive emerald ash borer (Coleoptera: Buprestidae): implications for laboratory rearing.

    Science.gov (United States)

    Duan, Jian J; Watt, Tim; Taylor, Phil; Larson, Kristi; Lelito, Jonathan P

    2013-10-01

    The emerald ash borer, Agrilus planipennis Fairmaire, an invasive beetle from Asia causing large scale ash (Fraxinus) mortality in North America, has been extremely difficult to rear in the laboratory because of its long life cycle and cryptic nature of immature stages. This lack of effective laboratory-rearing methods has not only hindered research into its biology and ecology, but also mass production of natural enemies for biological control of this invasive pest. Using sticks from the alternate host plant, Fraxinus uhdei (Wenzig) Lingelsh, we characterized the stage-specific development time and growth rate of both emerald ash borer eggs and larvae at different constant temperatures (12-35 degrees C) for the purpose of developing effective laboratory-rearing methods. Results from our study showed that the median time for egg hatching decreased from 20 d at 20 degrees C to 7 d at 35 degrees C, while no emerald ash borer eggs hatched at 12 degrees C. The developmental time for 50% of emerald ash borer larvae advancing to third, fourth, and J-larval stages at 20 degrees C were 8.3, 9.1, and 12.3 wk, respectively, approximately two times longer than at 30 degrees C for the corresponding instars or stages. In contrast to 30 degrees C, however, the development times of emerald ash borer larvae advancing to later instars (from oviposition) were significantly increased at 35 degrees C, indicating adverse effects of this high temperature. The optimal range of ambient temperature to rear emerald ash borer larvae should be between 25-30 degrees C; however, faster rate of egg and larval development should be expected as temperature increases within this range.

  4. Occurrence of gaseous and particulate polycyclic aromatic hydrocarbons in the urban atmosphere: study of sources and ambient temperature effect on the gas/particle concentration and distribution

    Energy Technology Data Exchange (ETDEWEB)

    Tsapakis, Manolis [Environmental Chemical Processes Laboratory (ECPL), Department of Chemistry, University of Crete, EL-71409 Heraklion (Greece); Stephanou, Euripides G. [Environmental Chemical Processes Laboratory (ECPL), Department of Chemistry, University of Crete, EL-71409 Heraklion (Greece)]. E-mail: stephanou@chemistry.uoc.gr

    2005-01-01

    The presence of polycyclic aromatic hydrocarbons (PAHs) in an urban region (Heraklion, Greece) and processes that govern their atmospheric fate were studied from November 2000 until February 2002. Sixteen samples were collected, by using an artifact-free sampling device, on a monthly basis and the concentration of PAHs in gas and particulate phase was determined. The most abundant members (gas + particles) were phenanthrene (20.0 {+-} 7.0 ng m{sup -3}), fluoranthene (6.5 {+-} 1.7 ng m{sup -3}), pyrene (6.6 {+-} 2.4 ng m{sup -3}), and chrysene (3.1 {+-} 1.5 ng m{sup -3}). Total concentration (gas + particulate) of PAH ranged from 44.3 to 129.2 ng m{sup -3}, with a mean concentration of 79.3 ng m{sup -3}. Total concentration of PAHs in gas phase ranged from 31.4 to 84.7 ng m{sup -3} with non-observable seasonal variation. Conversely, maximum PAH concentrations in the particulate phase occurred during winter months. Particulate concentration varied from 11.4 to 44.9 ng m{sup -3}, with an average of 25.2 ng m{sup -3}. PAH distribution between gas and particulate phase was in agreement with the sub-cooled vapor pressure. Shift in gas/particle distribution due to difference in ambient temperature elucidated to some extent the seasonal variation of the concentration of PAHs in particles. - Capsule: Ambient PAH partitioning between gas and particle phases vary between compounds and with environmental conditions.

  5. Ambient intelligence

    OpenAIRE

    Sanders, David; Gegov, Alexander

    2006-01-01

    This paper considers some history and the state of the art of Ambient Intelligence and from that seeks to identify new topics and future work. Ubiquitous computing, communications, human-centric computer interaction, embedded systems, context awareness, adaptive systems and distributed device networks are considered.

  6. Effect of feeding whole linseed as a source of polyunsaturated fatty acids on performance and egg characteristics of laying hens kept at high ambient temperature

    Directory of Open Access Journals (Sweden)

    S Ahmad

    2013-03-01

    Full Text Available The present study was conducted to evaluate the effects of feeding whole linseed on the laying performance and egg characteristics in laying hens kept at high ambient environmental temperatures (average 34 ºC; the diurnal temperature range 26 ºC to 41 ºC. Two hundred and forty 38-wk-old white Leghorn laying hens were fed diets containing 0, 5, 10 or 15% whole linseed (as a source of n-3 polyunsaturated fatty acids for a period of 12 weeks. Egg production was recorded daily, while feed intake and egg characteristics were monitored on weekly basis. The results of the study demonstrated that egg production and feed intake decreased, while feed conversion ratio (FCR per dozen of eggs increased (p 0.05 by linseed levels in the diets offered to the laying hens. The results of the present trial suggest that feeding linseed to the laying hens in hot climates has no detrimental effects on egg characteristics, but has suppressive effects on egg production, feed intake and feed efficiency of laying hens.

  7. Effects of ambient temperature and early open-field response on the behaviour, feed intake and growth of fast- and slow-growing broiler strains

    DEFF Research Database (Denmark)

    Nielsen, Birte Lindstrøm

    2012-01-01

    in an open-field test on day 3 after hatching, fast-growing Ross 208 and slow-growing i657 chickens were allocated on day 13 to one of the 48 groups. Each group included either six active or six passive birds from each strain and the groups were housed in floor-pens littered with wood chips and fitted......Increased activity improves broiler leg health, but also increases the heat production of the bird. This experiment investigated the effects of early open-field activity and ambient temperature on the growth and feed intake of two strains of broiler chickens. On the basis of the level of activity...... with two heat lamps. Each group was fed ad libitum and subjected to one of the three temperature treatments: two (HH; 268C), one (HC; 168C to 268C) or no (CC; 168C) heat lamps turned on. Production and behavioural data were collected every 2 weeks until day 57. For both strains, early open-field activity...

  8. Thermal conductivity of silver loaded conductive epoxy from cryogenic to ambient temperature and its application for precision cryogenic noise measurements

    Science.gov (United States)

    Amils, Ricardo I.; Gallego, Juan Daniel; Sebastián, José Luis; Muñoz, Sagrario; Martín, Agustín; Leuther, Arnulf

    2016-06-01

    The pressure to increase the sensitivity of instrumentation has pushed the use of cryogenic Low Noise Amplifier (LNA) technology into a growing number of fields. These areas range from radio astronomy and deep space communications to fundamental physics. In this context manufacturing for cryogenic environments requires a proper thermal knowledge of the materials to be able to achieve adequate design behavior. In this work, we present experimental measurements of the thermal conductivity of a silver filled conductive epoxy (EPO-TEK H20E) which is widely used in cryogenic electronics applications. The characterization has been made using a sample preparation which mimics the practical use of this adhesive in the fabrication of cryogenic devices. We apply the data obtained to a detailed analysis of the effects of the conductive epoxy in a monolithic thermal noise source used for high accuracy cryogenic microwave noise measurements. In this application the epoxy plays a fundamental role since its limited thermal conductivity allows heating the chip with relatively low power. To our knowledge, the cryogenic thermal conductivity data of this epoxy has not been reported before in the literature in the 4-300 K temperature range. A second non-conductive epoxy (Gray Scotch-Weld 2216 B/A), also widely used in cryogenic applications, has been measured in order to validate the method by comparing with previous published data.

  9. Ozone decomposition on Ag/SiO{sub 2} and Ag/clinoptilolite catalysts at ambient temperature

    Energy Technology Data Exchange (ETDEWEB)

    Nikolov, Penko, E-mail: penmail@mail.bg [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Genov, Krassimir; Konova, Petya [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Milenova, Katya; Batakliev, Todor; Georgiev, Vladimir [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Kumar, Narendra [Laboratory of Industrial Chemistry, Process Chemistry Centre, Abo Akademi University, Biskopsgatan 8, 20500 Abo/Turku (Finland); Sarker, Dipak K. [School of Pharmacy and Biomolecular Sciences, University of Brighton, Lewes Road, Brighton BN2 4GJ (United Kingdom); Pishev, Dimitar [University of Chemical Technology and Metallurgy, 1756 Sofia (Bulgaria); Rakovsky, Slavcho [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)

    2010-12-15

    Silver modified zeolite (Bulgarian natural clinoptilolite) and Ag/silica catalysts were synthesized by ion exchange and incipient wet impregnation method respectively and characterized by different techniques. DC arc-AES was used for Ag detection. XRD spectra show that Ag is loaded over the surface of the SiO{sub 2} sample and that after the ion-exchange process the HEU type structure of clinoptilolite is retained. UV-VIS (specific reflection at 310 nm) and IR (band at 695 cm{sup -1}) spectroscopy analysis proved that silver is loaded as a T-atom into zeolite channels as Ag{sup +}, instead of Na{sup +}, Ca{sup 2+}, or K{sup +} ions, existing in the natural clinoptilolite form. The samples Ag/SiO{sub 2} and Ag-clinoptilolite were tested as catalysts for decomposition of gas phase ozone. Very high catalytic activity (up to 99%) was observed and at the same time the catalysts remained active over time at room temperature.

  10. Cardiac-specific knockout of ETA receptor mitigates low ambient temperature-induced cardiac hypertrophy and contractile dysfunction

    Institute of Scientific and Technical Information of China (English)

    Yingmei Zhang; Linlin Li; Yinan Hua; Jennifer M. Nunn; Feng Dong; Masashi Yanagisawa; Jun Ren

    2012-01-01

    Cold exposure is associated with oxidative stress and cardiac dysfunction.The endothelin (ET) system,which plays a key role in myocardial homeostasis,may participate in cold exposure-induced cardiovascular dysfunction.This study was designed to examine the role of ET-1 in cold stress-induced cardiac geometric and contractile responses.Wild-type (WT) and ETA receptor knockout (ETAKO) mice were assigned to normal or cold exposure (4℃) environment for 2 and 5 weeks prior to evaluation of cardiac geometry,contractile,and intracellular Ca2+ properties.Levels of the temperature sensor transient receptor potential vanlllold (TRPV1),mitochondrlal proteins for biogenesis and oxidative phosphorylatlon,Including UCP2,HSP90,and PGC1α were evaluated.Cold stress triggered cardiac hypertrophy,depressed myocardial contractile capacity,including fractional shortening,peak shortening,and maximal velocity of shortening/relengthening,reduced intracellular Ca2+ release,prolonged intracellular Ca2+ decay and relengthening duration,generation of ROS and superoxide,as well as apoptosls,the effects of which were blunted by ETAKO.Western blotting revealed downregulated TRPV1 and PGC1α as well as upregulated UCP2 and activation of GSK3β,GATA4,and CREB in cold-stressed WT mouse hearts,which were obliterated by ETAKO.Levels of HSP90,an essential regulator for thermotolerance,were unchanged.The TRPV1 agonist SA13353 attenuated whereas TRPV1 antagonist capsazepino mimicked cold stress- or ET-1-induced cardiac anomalies.The GSK3β Inhibitor SB216763 ablated cold stress-induced cardiac contractile (but not remodeling) changes and ET-1-induced TRPV1 downregulation.These data suggest that ETAKO protects against cold exposure-induced cardiac remodeling and dysfunction mediated through TRPV1 and mitochondrlal function.

  11. 40 CFR 1033.505 - Ambient conditions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Ambient conditions. 1033.505 Section 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits...

  12. Application of Simplified Anaerobic Digestion Models (SADM’s for Studying the Biodegradability and Kinetics of Cow Manure at Ambient Temperature

    Directory of Open Access Journals (Sweden)

    Yusuf O.L. MOMOH

    2014-02-01

    Full Text Available The application of a set of simplified anaerobic digestion models (SADM’s to describe the anaerobic biodegradability and kinetics of cow manure at ambient temperature was conducted in this study. It was observed that the Hill’s based biogas yield rate model was the most appropriate in describing biogas yield rate from cow manure. Parameter estimation revealed that the half saturation constant expressed as acidified substrate and volatile solids (VS equivalent were 0.163g/l and 21.9g VS/l respectively while the maximum biogas yield rate was estimated to be 1.957ml/g VS/day. The coefficient of acidogenic bacteria adaptation (n and coefficient of acetogenic/methanogenic bacterial cooperativity (m were estimated to be 1.28 and 0.65 respectively. The poor cooperativity amongst the acetogenic/methanogenic bacterial species can be attributed to poor adaptation, possibly due to interaction between ammonia and volatile fatty acids. In addition, the biodegradability and recalcitrance was estimated to be 0.42 and 0.433 respectively, while hydrolysis/acidogenesis was identified as the rate limiting step.

  13. Imaging hydrothermal systems associated with oceanic ridge: ambient noise and travel-time tomographies in the Reykjanes high-temperature area, SW-Iceland.

    Science.gov (United States)

    Jousset, Philippe; Ágústsson, Kristjan; Verdel, Arie; Blanck, Hanna; Franke, Steven; Specht, Sebastian; Stefánsson, Stefán; Tryggvason, Hörður; Erbas, Kemal; Deon, Fiorenza; Erlendsson, Ögmundur; Guðnason, Egill; Hersir, Gylfi; Ryberg, Trond; Halldórsdóttir, Sæunn; Weemstra, Cornelius; Bruhn, David; Flovenz, Ólafur; Friðleifsson, Ómar

    2015-04-01

    Analogue outcrops of hydrothermal fossil systems and simulating pressure/temperature conditions in the laboratory are classical methods for assessing supercritical conditions in magmatic environments. Scientific drilling is used when Earth surface sampled rocks cannot sufficiently explain past geological processes and when geophysical imaging does not sufficiently explain observed phenomena. However, our understanding of structural and dynamic characteristics of geothermal systems can be improved through application of advanced and/or innovative exploration technologies. Unlike resistivity imaging, active and passive seismic techniques have rarely been used in volcanic geothermal areas, because processing techniques were not adapted to geothermal conditions. Recent advances in volcano-seismology have introduced new processing techniques for assessing subsurface structures and controls on fluid flow in geothermal systems. We present here preliminary analyses of seismic records around a geothermal reservoir located both on-land and offshore along the Reykjanes Ridge, SW-Iceland. We deployed 214 on-land stations and 24 Ocean Bottom Seismometers since April 2014. We analyse more than 6 months of part of those records. We present first results of both travel-time tomography and ambient noise tomography and we discuss briefly implications for geothermal exploration in volcanic contexts.

  14. Preparation and characterization of mesoporous TiO2-sphere-supported Au-nanoparticle catalysts with high activity for CO oxidation at ambient temperature

    Science.gov (United States)

    Wang, Lili; Huang, Shouying; Zhu, Baolin; Zhang, Shoumin; Huang, Weiping

    2016-11-01

    Mesoporous TiO2-sphere-supported Au-nanoparticles (Au/m-TiO2-spheres) catalysts have been synthesized by a simple method using tetrabutyl titanate as TiO2 precursor and characterized with XRD, BET, ICP, SEM, TEM, UV-Vis DRS, XPS, as well as FT-IR. The samples with the size in the range of 200-400 nm were almost perfectly spherical. The average diameter of pores was about 3.6 nm, and the mesopore size distribution was in the range of 2-6 nm with a narrow distribution. When the catalyst was calcined at 300 °C, the Au NPs with the size ca. 5 nm were highly dispersed on the surfaces of m-TiO2 spheres and partially embedded in the supports. Remarkably, the specific surface area of the Au/m-TiO2-spheres was as high as 117 m2 g-1. The CO-adsorbed catalyst showed an apparent IR adsorption peak at 1714 cm-1 that matched with bridging model CO. It means the catalysts should be of high catalytic activity for the CO oxidation due to they could adsorb and activate CO commendably. When Au-content was 0.48 wt.%, the Au/m-TiO2-spheres could convert CO completely into CO2 at ambient temperature.

  15. Influence of applied voltage on the performance of bioelectrochemical anaerobic digestion of sewage sludge and planktonic microbial communities at ambient temperature.

    Science.gov (United States)

    Feng, Qing; Song, Young-Chae; Bae, Byung-Uk

    2016-11-01

    The influence of applied voltage on the bioelectrochemical anaerobic digestion of sewage sludge was studied at ambient temperature (25±2°C). The stability of the bioelectrochemical anaerobic digestion was considerably good in terms of pH, alkalinity and VFAs at 0.3V and 0.5V, but VFA accumulation occurred at 0.7V. The specific methane production rate (370mLCH4/L.d) was the highest at 0.3V, but the methane content (80.6%) in biogas and the methane yield (350mLCH4/gCODr) were higher at 0.5V, significantly better than those of 0.7V. The VS removal efficiency was 64-66% at 0.3V and 0.5V, but only 31% at 0.7V. The dominant species of planktonic microbial communities was Cloacamonas at 0.3V and 0.5V, but the percentage of hydrolytic bacteria species such as Saprospiraceae, Fimbriimonas, and Ottowia pentelensis was much higher at 0.7V. The optimal applied voltage for bioelectrochemical anaerobic digestion was 0.3-0.5V according to digestion performance and planktonic microbial communities.

  16. Effects of dietary DL-2-hydroxy-4(methylthio)butanoic acid supplementation on growth performance, indices of ascites syndrome, and antioxidant capacity of broilers reared at low ambient temperature

    Science.gov (United States)

    Yang, G. L.; Zhang, K. Y.; Ding, X. M.; Zheng, P.; Luo, Y. H.; Bai, S. P.; Wang, J. P.; Xuan, Y.; Su, Z. W.; Zeng, Q. F.

    2016-08-01

    This study examined the effects of dietary DL-2-hydroxy-4(methylthio)butanoic acid (DL-HMTBA) supplementation on growth performance, antioxidant capacity, and ascites syndrome (AS) in broilers reared at low ambient temperature (LAT) from 7 to 28 days of age. Eight hundred 7-day-old broilers were randomly assigned to two ambient temperatures (LAT and normal ambient temperature [NAT]), four supplemental DL-HMTBA levels (0.17, 0.34, 0.51, and 0.68 %) of the basal diet in a 2 × 4 factorial arrangement (ten replicate pens; ten birds/pen). LAT and NAT indicate temperatures of 12-14 and 24-26 °C in two chambers, respectively, and broilers were reared at these temperatures from 7 to 28 days of age. LAT significantly decreased body weight gain ( P increased feed conversion ratio (FCR) ( P red blood cell (RBC) count ( P cell hemoglobin (day 14, P = 0.035; day 21, P = 0.003), and serum protein carbonyl level (day 21, P = 0.009), while significantly increased serum GSH content (day 14, P = 0.022; day 28, P = 0.001), SOD and GSH-Px activities at 21 days of age ( P < 0.001 and P = 0.037). The optimal supplemental DL-HMTBA levels in basal diet of broilers aged from 7 to 28 days under low or normal temperatures were similar, so the authors recommended supplemental of DL-HMTBA level was 0.46 %.

  17. Vaulted trans-bis(salicylaldiminato)platinum(II) crystals: heat-resistant, chromatically sensitive platforms for solid-state phosphorescence at ambient temperature.

    Science.gov (United States)

    Komiya, Naruyoshi; Okada, Minoru; Fukumoto, Kanako; Kaneta, Kenji; Yoshida, Atsushi; Naota, Takeshi

    2013-04-08

    The synthesis, structure, and solid-state emission of vaulted trans-bis(salicylaldiminato)platinum(II) complexes are described. A series of polymethylene (1: n=8; 2: n=9; 3: n=10; 4: n=11; 5: n=12; 6: n=13) and polyoxyethylene (7: m=2; 8: m=3; 9: m=4) vaulted complexes (R=H (a), 3-MeO (b), 4-MeO (c), 5-MeO (d), 6-MeO (e), 4-CF3O (f), 5-CF3O (g)) was prepared by treating [PtCl2(CH3CN)2] with the corresponding N,N'-bis(salicylidene)-1,ω-alkanediamines. The trans coordination, vaulted structures, and the crystal packing of 1-9 have been unequivocally established from X-ray diffraction studies. Unpredictable, structure-dependent phosphorescent emission has been observed for crystals of the complexes under UV excitation at ambient temperature, whereas these complexes are entirely nonemissive in the solution state under the same conditions. The long-linked complex crystals 4-6, 8, and 9 exhibit intense emission (Φ77K =0.22-0.88) at 77 K, whereas short-linked complexes 1-3 and 7 are non- or slightly emissive at the same temperature (Φ77K solid-state emission over the range of 98 nm can be performed simply by introducing MeO groups at different positions on the aromatic rings. Orange, yellow-green, red, and yellow emissions are observed in the glass and crystalline state upon 3-, 4-, 5-, and 6-MeO substitution, respectively, whereas those with CF3 O substituents have orange emission, irrespective of the substitution position. DFT calculations (B3LYP/6-31G*, LanL2DZ) showed that such chromatic variation is ascribed to the position-specific influence of the substituents on the highest-occupied molecular orbital (HOMO) and lowest-unoccupied molecular orbital (LUMO) levels of the trans-bis(salicylaldiminato)platinum(II) platform. The solid-state emission and its heat resistance have been discussed on the basis of X-ray diffraction studies. The planarity of the trans-coordination sites is strongly correlated to the solid-state emission intensities of crystals 1-9 at lower

  18. A stochastic model for transmission, extinction and outbreak of Escherichia coli O157:H7 in cattle as affected by ambient temperature and cleaning practices

    KAUST Repository

    Wang, Xueying

    2013-07-18

    Many infectious agents transmitting through a contaminated environment are able to persist in the environment depending on the temperature and sanitation determined rates of their replication and clearance, respectively. There is a need to elucidate the effect of these factors on the infection transmission dynamics in terms of infection outbreaks and extinction while accounting for the random nature of the process. Also, it is important to distinguish between the true and apparent extinction, where the former means pathogen extinction in both the host and the environment while the latter means extinction only in the host population. This study proposes a stochastic-differential equation model as an approximation to a Markov jump process model, using Escherichia coli O157:H7 in cattle as a model system. In the model, the host population infection dynamics are described using the standard susceptible-infected-susceptible framework, and the E. coli O157:H7 population in the environment is represented by an additional variable. The backward Kolmogorov equations that determine the probability distribution and the expectation of the first passage time are provided in a general setting. The outbreak and apparent extinction of infection are investigated by numerically solving the Kolmogorov equations for the probability density function of the associated process and the expectation of the associated stopping time. The results provide insight into E. coli O157:H7 transmission and apparent extinction, and suggest ways for controlling the spread of infection in a cattle herd. Specifically, this study highlights the importance of ambient temperature and sanitation, especially during summer. © 2013 Springer-Verlag Berlin Heidelberg.

  19. Effect of ambient temperature on the thermoregulatory and locomotor stimulant effects of 4-methylmethcathinone in Wistar and Sprague-Dawley rats.

    Directory of Open Access Journals (Sweden)

    M Jerry Wright

    Full Text Available The drug 4-methylmethcathinone (4-MMC; aka, mephedrone, MMCAT, "plant food", "bath salts" is a recent addition to the list of popular recreational psychomotor-stimulant compounds. Relatively little information about this drug is available in the scientific literature, but popular media reports have driven recent drug control actions in the UK and several US States. Online user reports of subjective similarity to 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy" prompted the current investigation of the thermoregulatory and locomotor effects of 4-MMC. Male Wistar and Sprague-Dawley rats were monitored after subcutaneous administration of 4-MMC (1-10 mg/kg using an implantable radiotelemetry system under conditions of low (23°C and high (27°C ambient temperature. A reliable reduction of body temperature was produced by 4-MMC in Wistar rats at 23°C or 27°C with only minimal effect in Sprague-Dawley rats. Increased locomotor activity was observed after 4-MMC administration in both strains with significantly more activity produced in the Sprague-Dawley strain. The 10 mg/kg s.c. dose evoked greater increase in extracellular serotonin, compared with dopamine, in the nucleus accumbens. Follow-up studies confirmed that the degree of locomotor stimulation produced by 10 mg/kg 4-MMC was nearly identical to that produced by 1 mg/kg d-methamphetamine in each strain. Furthermore, hypothermia produced by the serotonin 1(A/7 receptor agonist 8-hydroxy-N,N-dipropyl-2-aminotetralin (8-OH-DPAT was similar in each strain. These results show that the cathinone analog 4-MMC exhibits thermoregulatory and locomotor properties that are distinct from those established for methamphetamine or MDMA in prior work, despite recent evidence of neuropharmacological similarity with MDMA.

  20. A thiol-activated lipase from Trichosporon asahii MSR 54: detergent compatibility and presoak formulation for oil removal from soiled cloth at ambient temperature.

    Science.gov (United States)

    Kumar, S Suresh; Kumar, Lalit; Sahai, Vikram; Gupta, Rani

    2009-03-01

    An alkaline lipase from Trichosporon asahii MSR 54 was used to develop presoak formulation for removing oil stains at ambient temperature. The lipase was produced in a reactor followed by concentration by ultrafiltration and then it was dried with starch. The biochemical characteristics of enzyme showed that it was an alkaline lipase having pH activity in the range of pH 8.0-10.0 and temperature in the range of 25-50 degrees C. The present lipase was active >80% at 25 degrees C. The lipase was cystein activated with fourfold enhancement in presence of 5 mM cystein and likewise the activity was also stimulated in presence of papain hydrolysate which served as source of cystein. The presoak formulation consisted of two components A and B, component A was enzyme additive and B was a mixture of carbonate/bicarbonate source of alkali and papain hydrolysate as source of cystein. The results indicated that the presoaking in enzyme formulation followed by detergent washing was a better strategy for stain removal than direct washing with detergent in presence of lipase. Further, it was observed that 0.25% presoak component B in presence of 100 U enzyme component A (0.1 g) was the best formulation in removing maximum stain from mustard oil/triolein soiled clothes as indicated by increase in reflectance which was found equal to that of control cloth. The lipase action in presoaked formulation was clearly indicated by quantitated fatty acid release and also the TLC results of wash water, where oil hydrolytic products were visible only in presence of enzyme in the treatment. The wash performance carried at 25 degrees C indicated that washing at 25 degrees C was at par with that at 40 degrees C as indicated by similar reflectance of the washed cloth piece though qualitative fatty acid release was higher at 40 degrees C.

  1. Temperatura e enriquecimento ambiental sobre o bem-estar de coelhos em crescimento Temperature and environmental enrichment on the welfare of growing rabbits

    Directory of Open Access Journals (Sweden)

    Estela Valéria Siloto

    2009-04-01

    Full Text Available O efeito da temperatura e o efeito do enriquecimento do piso de gaiola sobre o bem-estar de coelhos em crescimento foram avaliados. Quarenta e oito coelhos do grupo genético Botucatu, desmamados aos 35 dias de idade, foram alojados em Câmara Climática, quatro por gaiola (1,00 x 0,60 x 0,40m, em 12 gaiolas que tinham (ou não metade do piso coberto com cama de palha. As gaiolas foram instaladas metade em sala com temperatura ambiente e metade em sala resfriada. Os animais tiveram livre acesso à ração balanceada e à água nos dois tipos de piso. Para se avaliar o bem-estar, foram realizadas cinco observações de 24 horas cada, uma por semana, sendo registradas as freqüências dos comportamentos: lúdico, estereotipado, exploratório, cuidados corporais e interação e comparadas entre gaiolas enriquecidas ou não nas duas salas. A média de temperatura e a média de umidade relativa do ar foram: 23,6°C e 78,7% na sala natural e 20,6°C e 71,0% na sala resfriada. O comportamento lúdico foi mais freqüente nas gaiolas enriquecidas (7,6 vs 4,3% sala natural e 7,8 vs 3,8% sala resfriada, P0,01. Coelhos mantidos em temperatura natural preferiram a grade à cama de palha (77,9 vs. 22,1%, P>0,01, enquanto na sala resfriada eles não mostraram preferência em relação ao piso (45,9 vs 54,1%, P=0,41. Em sala resfriada, o enriquecimento com palha favoreceu o bem-estar animal.The effects of temperature and cage floor enrichment on the welfare of growing rabbits were evaluated. Forty-eight rabbits from the Botucatu genetic group, weaned at 35 days of age were housed in an Environmental Chamber, four per cage (1.00 x 0.60 x 0.40m, in 12 cages that had (or not half of the floor covered with litter straw. The cages were housed half in a room temperature chamber and half in a refrigerated chamber. Animals had free access to a balanced feed and water in the two types of floor. In order to evaluate welfare, five 24-hour observations were carried out

  2. Temperaturas superficiais de telhas e sua relação com o ambiente térmico Superficial temperatures of tiles and the relation with thermal environment

    Directory of Open Access Journals (Sweden)

    Carlos A. de P. Sampaio

    2011-04-01

    Full Text Available Este trabalho teve como objetivo a análise de temperaturas de telhas de barro, de fibrocimento com pintura branca na face superior e de aço zincado e sua relação com o ambiente térmico, quantificando também os Índices de Temperatura e Umidade (ITU, de Temperatura de Globo e Umidade (ITGU e Carga Térmica de Radiação (CTR. As análises foram realizadas em modelos de edificações e na área não sombreada. Os resultados mostraram que as telhas cerâmicas e de fibrocimento apresentaram comportamentos térmicos semelhantes, sendo que a opção pela telha de fibrocimento de 5 mm, pintada de branca na sua face superior, é vantajosa economicamente. As telhas metálicas superaram os 53 °C na sua superfície e foram piores no conforto térmico comparado com as outras telhas. O ITGU foi superior na indicação do conforto térmico em relação ao ITU, principalmente no verão. Houve redução significativa da CTR pelas telhas em relação à área não sombreada.The objective of this study was the analysis of temperatures of clay tiles, galvanized steel tiles and fiber-cement tiles with white painting on the roof and his relation with the thermal environment, in winter and summer conditions. The experiment was carried out in models of constructions quantifying the internal and extern temperatures from the tiles (TS, Temperature and humidity index (THI, Black Globe and Humidity (BGHI and Thermal Load of Radiation (TLR were employed for the characterization of the thermal environmental. The measured were performed inside and outside the housing. The results showed that the ceramic tiles and the fiber-cement tiles presented similar thermal behaviors and the choice of fiber-cement tiles of 5 mm with white painting on the roof is economically advantageous. The metal tiles were the ones that most heated up surpassing 53ºC in his surface and the worst regarding to the thermal comfort compared with the other tiles. The THI was not accurate for

  3. The effect of natural and synthetic antioxidants on performance, egg quality and blood constituents of laying hens grown under high ambient temperature

    Directory of Open Access Journals (Sweden)

    Mohammed A. Al-Harthi

    2014-06-01

    Full Text Available A total of 216 laying hens was kept at high ambient temperature (32±4°C, 60% relative humidity from week 24 to 32 of age. Birds were divided in 8 treatments with 9 replicates of 3 hens each. The groups were fed the same basal diet and submitted to these dietary treatments: control, un-supplemented; green tea (GT, fed GT at 1 g/kg diet; brown marine algae (BMA, fed BMA at 1 g/kg diet; vitamin E (vit. E, fed vit. E at 300 mg/kg diet; GT+BMA, fed GT and BMA at 1 g/kg of each; GT+vit. E, fed GT and vit. E at 1 g and 300 mg/kg, respectively; BMA+vit. E, fed BMA and vit. E at 1 g and 300 mg/kg, respectively. Feeding BMA at 0.1% increased laying rate by 1.2% and improved feed conversion ratio by 5.2% compared to the control. Vitamin E significantly increased shell thickness by 6.6% and Haugh unit by 4.6% compared to the control. In addition, BMA+vit. E or GT+vit. E increased yolk colour by 9.1 and 10.7%, and Haugh unit of stored eggs by 10.9 and 11.1%. Cholesterol of fresh eggs and plasma were significantly decreased by 16.0 and 9.4% due to supplementation with BMA, and by 19.2 and 8.1% with vit. E addition. Plasma phosphorus increased by 19.1% after vit. E+BMA supplementation. In conclusion, use of BMA or vit. E or GT in laying hens diets which grow under heat stress is recommended as it improves production performance and egg quality.

  4. Ion mobility spectrometric analysis of vaporous chemical warfare agents by the instrument with corona discharge ionization ammonia dopant ambient temperature operation.

    Science.gov (United States)

    Satoh, Takafumi; Kishi, Shintaro; Nagashima, Hisayuki; Tachikawa, Masumi; Kanamori-Kataoka, Mieko; Nakagawa, Takao; Kitagawa, Nobuyoshi; Tokita, Kenichi; Yamamoto, Soichiro; Seto, Yasuo

    2015-03-20

    The ion mobility behavior of nineteen chemical warfare agents (7 nerve gases, 5 blister agents, 2 lachrymators, 2 blood agents, 3 choking agents) and related compounds including simulants (8 agents) and organic solvents (39) was comparably investigated by the ion mobility spectrometry instrument utilizing weak electric field linear drift tube with corona discharge ionization, ammonia doping, purified inner air drift flow circulation operated at ambient temperature and pressure. Three alkyl methylphosphonofluoridates, tabun, and four organophosphorus simulants gave the intense characteristic positive monomer-derived ion peaks and small dimer-derived ion peaks, and the later ion peaks were increased with the vapor concentrations. VX, RVX and tabun gave both characteristic positive monomer-derived ions and degradation product ions. Nitrogen mustards gave the intense characteristic positive ion peaks, and in addition distinctive negative ion peak appeared from HN3. Mustard gas, lewisite 1, o-chlorobenzylidenemalononitrile and 2-mercaptoethanol gave the characteristic negative ion peaks. Methylphosphonyl difluoride, 2-chloroacetophenone and 1,4-thioxane gave the characteristic ion peaks both in the positive and negative ion mode. 2-Chloroethylethylsulfide and allylisothiocyanate gave weak ion peaks. The marker ion peaks derived from two blood agents and three choking agents were very close to the reactant ion peak in negative ion mode and the respective reduced ion mobility was fluctuated. The reduced ion mobility of the CWA monomer-derived peaks were positively correlated with molecular masses among structurally similar agents such as G-type nerve gases and organophosphorus simulants; V-type nerve gases and nitrogen mustards. The slope values of the calibration plots of the peak heights of the characteristic marker ions versus the vapor concentrations are related to the detection sensitivity, and within chemical warfare agents examined the slope values for sarin, soman

  5. Spatial and temporal variation of phthalic acid esters (PAEs) in atmospheric PM10 and PM2.5 and the influence of ambient temperature in Tianjin, China

    Science.gov (United States)

    Kong, Shaofei; Ji, Yaqin; Liu, Lingling; Chen, Li; Zhao, Xueyan; Wang, Jiajun; Bai, Zhipeng; Sun, Zengrong

    2013-08-01

    Phthalic acid esters (PAEs) are produced in large amounts throughout the world and are excessively used in various industries, which have posed a serious threat to human health and the environment. An investigation of six major PAEs congeners in atmospheric PM10 and PM2.5 was synchronously conducted at seven sites belonging to different functional zones in spring, summer and winter in Tianjin, China in 2010. Results showed that the average concentrations of DMP, DEP, DBP, BBP, DEHP and DOP in PM10 were 0.88, 0.73, 12.90, 0.15, 98.29 and 0.83 ng m-3, respectively, and in PM2.5, they were 0.54, 0.30, 8.72, 0.08, 75.68 and 0.33 ng m-3, respectively. DEHP and DBP were the predominant species. The industrial site exhibited highest PAEs values as 135.9 ± 202.8 ng m-3. In winter, the detected percentages for DOP were low. The other five PAEs concentrations were higher in winter than those in spring and summer, which may be related to the influence of emission sources, meteorological parameters and the chemical-physical characteristic of themselves. Except for DOP, other PAEs were negatively correlated with ambient temperature and the relationships were the best fitted as exponential forms. Significant positive correlations were found for PAEs in PM2.5 and PM10, indicating common sources. The PM2.5/PM10 ratios (0.53-0.70) for the six PAEs concentrations suggested that they were preferentially concentrated in finer particles. Principal component analysis indicated the emission from cosmetics and personal care products, plasticizers and sewage and industrial wastewater may be important sources for PAEs in atmospheric particulate matter in Tianjin.

  6. Um banho termostático de baixo custo (temperatura ambiente até 0ºC A low cost thermal bath (room temperature to 0 ºC

    Directory of Open Access Journals (Sweden)

    Cristina M. Quintella

    2003-01-01

    Full Text Available Thermal baths to decrease ambient temperature are an indispensable tool for most research and teaching laboratories, especially those in tropical or equatorial regions. A simple and inexpensive thermal bath has been developed based on a scratched compressor. It has three possible setups for cooling: sample immersed into the bath, sample flowing through the bath, and cooling liquid flowing in a jacket around the sample. It has been tested for 40 months. The temperature ranges from room temperature to 0 °C, when using water. The repeatability is better than 3% and the precision varies from 0.5% to 2%.

  7. Effect of Ambient Temperature on Industrial Applications of Sewage Sludge Composting%环境温度对污泥堆肥工业化生产的影响

    Institute of Scientific and Technical Information of China (English)

    宋应民; 刘瑞龙; 耿春茂; 王艳

    2014-01-01

    城市污泥堆肥受各种理化参数的影响,也与环境温度有密切关系。本试验通过对不同季节污泥堆肥过程及环境温度进行研究,表明污泥堆肥过程中,环境温度对污泥堆肥的升温存在影响,同时高温期内环境温度的波动对堆体温度影响较大;夏季堆肥无论其堆肥周期还是堆肥质量都优于冬季堆肥。%Sewage sludge compost affected by various physical and chemical parameters, but also closely related to the ambient temperature. In this research, in order to study the affection of ambient temperature, we made sewage sludge compost on different seasons. Our study shows that the warming up time, the change of compost temperature and the compost period were highly affected by ambient temperature. Compost in summer was better than winter for compost period and compost quality.

  8. Intellectual productivity under task ambient lighting

    OpenAIRE

    2016-01-01

    A subjective experiment was conducted to evaluate intellectual productivity in three lighting conditions: (a) conventional ambient lighting, (b) task ambient lighting with normal colour temperature (5000 K), and (c) task ambient lighting with high colour temperature (6200 K). In the experiment, cognitive tasks were given to 24 participants. The concentration time ratio, which is a quantitative and objective evaluation index of the degree of concentration, was measured. The results showed that...

  9. 环境温度对磷酸镁水泥凝结时间和强度发展的影响%Effect of Ambient Temperature on Setting Time and Strength Development of Magnesia-phosphate Cement

    Institute of Scientific and Technical Information of China (English)

    王庆珍; 钱觉时; 秦继辉; 尤超; 汪宏涛

    2013-01-01

    The confrontation between the prolonged setting time and high early strength impairs the practical use of magne-sia-phosphate cement (MPC) at a higher ambient temperature. The effect of ambient temperature on the setting time and strength de-velopment of MPC was investigated. The ambient temperatures used were 15, 20, 25, 30 and 35℃, and the borax contents used were 3%, 6%, 9% and 12%, respectively. An approach that the MPC paste after casting was cured for different periods at elevated ambient temperature was used to improve the early strength development of MPCs with a high borax content. The relationship between early temperature rise within MPC and setting time and early strength development of MPC were analyzed. The results show that a higher ambient temperature produces a faster early strength development and a quicker setting for MPC. At all ambient temperatures, the setting time was delayed and the early strength decreased with increasing the borax content. The higher and sooner the peak in the temperature rise curve, the faster the early strength and the quicker the setting could be. The initial setting time of MPC is 40min at the borax content of 12% and ambient temperature of 25℃. The strength at 1.5h increases to 27.2MPa when the elevating curing temperature increases to 50℃ for 10min after casting. It is suggested that increasing of borax content and elevating curing tempera-ture after casting could meet the practical engineering requirements on setting time and early strength of MPC.%在较高环境温度条件下,磷酸镁水泥(MPC)足够长的凝结时间和高早强之间的矛盾影响其实际应用。研究了环境温度为15、20、25、30和35℃,硼砂掺量为3%、6%、9%和12%时,MPC净浆凝结时间和抗压强度的变化规律。并研究了高硼砂掺量的MPC浇注一段时间后提高环境温度对其早期强度的改善作用,测量MPC体系早期温升曲线,并与凝结时间和早期强度相联系。结果

  10. Storage and Transport Technology of Hami Melon at Ambient Temperature%哈密瓜常温保鲜贮运技术研究

    Institute of Scientific and Technical Information of China (English)

    于新; 李竞; 张维一

    2002-01-01

    该研究旨在解决新疆哈密瓜采后低温贮运费用高,常温贮运腐烂率高,损失严重的问题.针对哈密瓜采后腐烂的主要病原菌匍枝根霉(R.stolonifer)、链格孢霉(A. Alternata)、半裸镰刀菌(F.semitectum)、脂状青霉(P.digitatum),筛选出对症的抑菌剂,并研究其最适使用浓度;以常温贮藏哈密的瓜失重率、呼吸强度、过氧化氢酶(CAT)、纤维素酶、果胶甲酯酶(PE)、多聚半乳糖醛酸酶(PG)活性等为指标,研究云南虫胶作为被膜对哈密瓜采后生理的影响及其最适使用浓度.含有0.60 g/L扑海因、0.8 g/L氯硝胺、0.6 g/L特克多、0.8 g/L施宝功和1∶24(V*V-1)虫胶的混合溶液浸泡哈密瓜10 s,于28℃,85% RH,贮藏30 d,腐烂率1.87%,同期对照腐烂率49.54%.处理后的哈密瓜在室外温度28~34℃、棚车内温度30~38℃的条件下,经过12~15 d由新疆哈密运抵苏州、上海、广州的腐烂率分别为3.37%、4.12%和4.86%.哈密瓜表皮以内0.8 cm几乎无抑菌剂残留.用上述配方的虫胶与抑菌剂的混合溶液浸泡哈密瓜,可有效降低哈密瓜采后常温贮运中的腐烂率,保持良好风味和商品质量,大量节省运输费用.%The research objective is to reduce expensive costs on storage and transport at low temperature and large loss at ambient temperature of Xinjiang Hami melon. The main pathogenic fungi, Rhizopus.stolonifer, Alternaia alternata, Fusarium semitectum, Penicillium digitatum were identified by potato-sucrose culture medium. Effective fungicides and their optimum application were assessed. Weight loss, respiration intensity(RI), and the activities of catalase(CAT), cellulase, pectinesterase(PE), polygalacturonase(PG) of Hami melon were measured during storage at normal atmospheric temperature. The use of shellac coat for physiological activities of postharvest Hami melon was evaluated. The melon was soaked in the solution with 0.6 g/L Iprodione, 0.8 g/L Botran, 0.6 g

  11. Armazenamento da polpa de acerola em pó a temperatura ambiente Storage of the pulp of powdered west indian cherry the temperature adapts

    Directory of Open Access Journals (Sweden)

    Patrícia M. de A. Gomes

    2004-09-01

    Full Text Available Este trabalho foi realizado com o objetivo de se estudar o armazenamento da polpa de acerola em pó embalada em sacos de polietileno durante 60 dias, sob atmosfera ambiente. O pó de acerola foi obtido mediante a secagem de uma solução contendo 90% de polpa de acerola e 10% de maltodextrina, em um secador do tipo leito de jorro, com temperatura do ar de secagem de 70ºC. A cada 10 dias foram feitas avaliações dos parâmetros ácido ascórbico, umidade, pH e cor. Os resultados demonstraram uma diminuição no teor de ácido ascórbico de 29,72%; um aumento de 51,31% na umidade; o valor do pH permaneceu praticamente inalterado oscilando entre 3,7 e 3,8 unidades de pH e observou-se alterações na cor do pó de acerola ao final do armazenamento, com acréscimo nos valores da intensidade de vermelho e amarelo e diminuição da luminosidade.This work had for objective, to study the storage of the pulp of powdered West Indian cherry wrapped in sacks of polyethylene for 60 days, under atmosphere it adapts. The West indian cherry powder was obtained by the drying of a solution containing 90% of West Indian cherry pulp and 10% of maltodextrin, in a dryer of the type spouted bed, with temperature of the air of drying of 70ºC. Every 10 days were made evaluations of the parameters ascorbic acid, humidity, pH and color. The results a decrease in the tenor of ascorbic acid of 29.72%; an increase of 51.31% in the humidity; the value of the pH stayed practically unaffected oscillating between 3.7 and 3.8 units of pH and it was observed alterations in the color of the West Indian cherry powder at the end of the storage, with increment in the values of the intensity of red and yellow and decrease of the brightness

  12. Effect of solar radiation and flaxseed supplementation on milk production and fatty acid profile of lactating ewes under high ambient temperature.

    Science.gov (United States)

    Caroprese, M; Albenzio, M; Bruno, A; Fedele, V; Santillo, A; Sevi, A

    2011-08-01

    The objectives of this study were to evaluate the effects of protection from solar radiation and whole flaxseed supplementation on milk yield and milk fatty acid profile in lactating ewes exposed to high ambient temperature. The experiment was conducted during summer and involved 40 ewes divided into 4 groups. The ewes were either exposed (not offered shade) or protected from solar radiation (offered shade). For each solar radiation treatment, ewes were supplemented with whole flaxseed or not. Milk samples from each ewe were collected at the morning and afternoon milking every week, and analyzed for pH, total protein, casein, fat, and lactose content, somatic cell count, and renneting parameters (clotting time, rate of clot formation, and clot firmness after 30 min). At the beginning of the experiment, and then at d 23 and 44, milk samples were analyzed for milk fatty acids using gas chromatography. Flaxseed supplementation significantly increased milk yield, fat, protein, and casein yields, and somatic cell count, and increased fat and lactose contents of milk. A decrease of saturated fatty acids from C6:0 to C16:0 and an increase of C18:1 trans-11 and C18:2 cis-9,trans-11 was observed in milk from flaxseed-supplemented ewes. Flaxseed supplementation decreased saturated fatty acids content and increased total monounsaturated fatty acids content, the total content of isomers of conjugated linoleic acid, and polyunsaturated fatty acids content in milk. Flaxseed also increased the α-linolenic acid content of milk. As a result, milk from supplemented groups showed an increase in n-3 fatty acid content. Flaxseed supplementation decreased short-chain and medium-chain fatty acids, and increased long-chain fatty acid content of milk. On average, flaxseed supplementation increased the C18:2 cis-9,trans-11/C18:1 trans-11 Δ(9)-desaturase index starting from d 23 of the experiment, in correspondence with the highest C18:2 cis-9,trans-11 content of milk from flaxseed

  13. 限制曝气实现常温条件下生活污水短程硝化%Partial Nitrification from Domestic Wastewater by Aeration Control at Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    彭永臻; 高守有; 王淑莹; 白璐

    2007-01-01

    The objective of this paper was to examine the feasibility of partial nitrification from raw domestic wastewater at ambient temperature by aeration control only. Airflow rate was selected as the sole operational parameter. A 14L sequencing batch reactor was operated at 23℃ for 8 months, with an input of domestic wastewater.deficiency in the reactor would eventually induce only nitrification to nitrite and not further to nitrate and that this system showed relatively stability at higher airflow rate independent of pH and temperature. About 50% of influent total nitrogen was eliminated coupling with partial nitrification, taking the advantage of low DO during the reaction.

  14. Morfometria da mucosa duodenal em frangos de corte submetidos à temperatura ambiente cíclica elevada Intestinal morphometry of the duodenal mucosa in broiler chickens underwent to high cyclic environment temperature

    Directory of Open Access Journals (Sweden)

    C.F.P. Marchini

    2009-04-01

    Full Text Available Os efeitos da temperatura ambiente cíclica elevada sobre a morfometria da mucosa duodenal e o peso corporal em frangos de corte foram avaliados. Setenta pintos de corte, machos, foram alojados em gaiolas e distribuídos em dois grupos. Um grupo foi submetido diariamente, durante uma hora, à temperatura ambiente cíclica elevada do primeiro até o 42º dia de idade (ambiente ST; e outro foi mantido em conforto térmico (ambiente TN. Cinco frangos de cada grupo foram sacrificados, semanalmente, por deslocamento cervical para mensuração da altura de vilosidades (VI, profundidade das criptas (CR e relação vilo/cripta (VI/CR duodenal. Dez aves de cada grupo foram pesadas semanalmente em balança digital. Utilizou-se delineamento inteiramente ao acaso em esquema fatorial 7x2 (sete idades: um, sete, 14, 21, 28, 35 e 42 dias, e dois ambientes: ST e TN. Os ambientes foram comparados pelo teste de Fisher (PThe effects of high cyclic environment temperature on body weight and morphometry of the duodenal mucosa in broiler chicken were evaluated. Seventy one-day-old male broiler chicks were sheltered in cages and distributed in two groups. One group was daily exposed to high cyclic environment temperature for an hour, from hatching to 42 days of age (group ST, the other one was kept under thermoneutral conditions (group TN. Five chickens of each group were weekly slaughtered by cervical delocation to mesure the villosities height (VI, crypts depth (CR, and villo/crypt ratio (VI/ CR in the duodenum. Ten chickens of each group were weighted weekly on a digital balance. A completely randomized experimental design in a 7x2 factorial arrangement (hatching, seven, 14, 21, 28, 35, and 42 days of age and two environments: ST and TN. The environments were compared by Fisher test (P<0.05 and the effects of days of life by polynomial regression. The ST group had reduction in VI at 14 and 21 days of age (P<0.01, CR at 28 days of age (P<0.05, and in VI/CR at 21

  15. Lithium-doped MOF impregnated with lithium-coated fullerenes: a hydrogen storage route for high gravimetric and volumetric uptakes at ambient temperatures.

    Science.gov (United States)

    Rao, Dewei; Lu, Ruifeng; Xiao, Chuanyun; Kan, Erjun; Deng, Kaiming

    2011-07-21

    We theoretically demonstrated that by the impregnation of Li-decorated IRMOF-10 with Li-coated C(60), the hydrogen storage capacity is improved to be 6.3 wt% and 42 g L(-1) at 100 bar and 243 K. Both the gravimetric and volumetric hydrogen uptakes reach the 2015 DOE target at near ambient conditions.

  16. 40 CFR 610.60 - Non-standard ambient conditions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Non-standard ambient conditions. 610... Non-standard ambient conditions. (a) Extreme temperatures. For vehicles required to be tested at... dynamometer, in ambient temperatures outside the 60° to 90° range specified in § 610.64 as determined by...

  17. Changes of Textural and Rheological Properties of Sterilized Processed Cheese Stored at Ambient Temperature%灭菌再制干酪常温储藏下质地和流变学特性变化

    Institute of Scientific and Technical Information of China (English)

    史亚丽; 李晓东; 王业菊

    2011-01-01

    To make the fact true that processed cheese can be stored at ambient temperature which can also save costs,sensory quality,textural and rheological properties of sterilized processed cheese(117 ℃,20 min) stored at ambient temperature and unsterilized processed cheese stored at low temperature were studied in this research.Sensory qualities and texture of sterilized processed cheese can be accepted.Sensory qualities,textural and rheological properties were found to be affected significantly by storage temperature(p0.05).And processed cheese stored at ambient temperature could not be accepted at the eighth week.Its hardness and springiness decreased,and it became much liquid.Fat were found to melt and overflow from the inside.%为实现再制干酪的常温储藏,节约成本,便于运输,试验对储藏在常温(23±2℃)下二次灭菌的再制干酪(117℃,20 min)和低温下未经灭菌再制干酪的感官、质构和流变学特性进行了研究。通过对储藏两个月内样品的各项指标进行对比分析,得出灭菌后再制干酪感官和质地可以接受,储藏温度对其感官、质构和流变学性质有显著影响(p〈0.05),经二次灭菌再制干酪第8周感官上已不具有可接受性,产品硬度和弹性下降,流体性增加,微观结构发现脂肪熔化溢出。

  18. Study on Effect of Storage in Ambient Temperature of Boar Semen Using Different Diluent%不同稀释液对公猪精液常温保存效果的研究

    Institute of Scientific and Technical Information of China (English)

    陈玉霞; 孙克宁; 林峰; 杨婷; 高汉婷; 高腾云

    2012-01-01

    In order to improve the storage effect of boar semen, three diluent formulas in ambient temperature was designed to preserve the boar semen, and the acrosome of the sperms was stained after they were preserved.The results showed that the storage time of the sperms stored by formula II was obviously different(P0.05) and all more than 95%.The storage effect of formula Ⅱ for sperms was better than that of formula I and formula Ⅲ in ambient temperature.This study provids the reference basis for the research of the storage technology in ambient temperature of boar semen and the semen diluents formula.%为提高猪精液的保存效果,设计了3种常温保存稀释液配方,并对保存后的精子进行了顶体染色,为猪精液常温保存技术及稀释液配方的研究提供参考依据.结果表明:当精子活率为50%与30%时,配方Ⅱ的精子保存时间均显著高于(P<0.05)配方Ⅰ与配方Ⅲ,且配方Ⅱ所保存精子的总存活时间也显著高于(P<0.05)配方Ⅰ与配方Ⅲ;在精液保存24h后,3种配方保存的精子顶体完整率均在95%以上,且差异不显著(P>0.05),配方Ⅱ对精子的常温保存效果要优于配方Ⅰ与配方Ⅲ.

  19. 计及温度的永磁操动机构动态特性仿真与分析%The simulation and analysis on permanent magnetism actuator dynamic characteristics considering ambient temperatures

    Institute of Scientific and Technical Information of China (English)

    张庆杰; 袁海文; 刘颖异

    2011-01-01

    针对环境温度变化会对永磁操动机构动态特性产生较明显影响的问题,考虑到温度变化的影响,建立永磁操动机构运动过程中两个阶段动态特性的数学模型.利用其模型,分析了计及温度的静态特性参数与电容器电容、线圈电阻等动态特性参数的温度特性,得到计及温度的永磁操动机构动态特性.通过计算及实验分析表明,在工作温度范围内,分合闸时间分散性较大,而在考虑温度影响后的动态特性计算结果与实验测试结果更为接近.通过分析曲线发现:当温度发生变化时,永磁操动机构的特性参数受温度影响的程度是不同的,即永磁体的性能参数受影响最大,其次是电容器电容,最后是线圈电阻.该计及温度的永磁机构特性分析方法可为完善同步投切控制及优化机构设计等方面提供理论指导和依据.%Aimed at impact on dynamic characteristics of permanent magnetic actuator as ambient temperature change, the paper establishes the dynamic characteristics mathematical models in two movement stages of permanent magnetic actuator considering ambient temperature impact. Based on the models, the paper analysed the static characteristics parameters considering ambient temperature and the temperature characteristics of control capacitor value and coil resistance. And the dynamic characteristics of permanent magnetic actuator taking the temperature into account were obtained in the paper. Experimental results show that in working temperature range, switching time dispersion is bigger and the dynamic characteristics calculation results of permanent magnetic actuator considering ambient temperature implications are closer to experimental test results. The temperature impact levels of permanent magnetic actuator characteristics parameters are different when the temperature changes after the curves are analyzed. And the largest temperature impact level is magnet performance parameters

  20. Influence of daily ambient temperature on mortality and years of life lost in Chongqing%重庆市逐日温度对人群死亡及寿命损失年影响的研究

    Institute of Scientific and Technical Information of China (English)

    李静; 罗书全; 丁贤彬; 杨军; 李京; 刘小波; 高景宏; 许磊; 唐文革

    2016-01-01

    目的 量化逐日温度对重庆市人群死亡率及寿命损失年(YLL)的影响.方法 利用2010-2013年重庆市主城区全人群死亡个案资料,结合同期气象及空气污染资料,采用分布滞后非线性模型(DLNM)拟合逐日平均气温与逐日死亡数及逐日YLL的关系,分析高温和低温对不同疾病别、不同人群死亡率及YLL的累积滞后效应.结果 日均气温与非意外、心血管系统及呼吸系统疾病死亡的日死亡数和日YLL呈“U”或“W”形.高温当日可增加人群死亡风险,累积滞后效应在第7天时达到最大,持续2周;低温滞后1周后才表现出危害效应,持续时间长达30 d.高温时,日均气温每升高1℃,人群非意外、呼吸系统和心血管系统疾病死亡的7d累积相对危险度(CRR)分别为1.05(95%CI:1.03~ 1.07)、1.08(95%CI:1.05~1.11)、1.05 (95%CI:1.01~ 1.09),YLL分别为23.81 (95%CI:12.31~ 35.31)年、14.34(95%CI:8.98~19.70)年、4.43 (95%CI:1.64~7.21)年;低温时,日均气温每降低1℃,人群非意外死亡、呼吸系统和心血管系统疾病死亡的14dCRR分别为1.06(95%CI:1.04~1.08)、1.09(95%CI:1.06~1.12)、1.06(95%CI:1.02~1.11);YLL分别为23.34(95%C1:10.04~36.64)年、16.39 (95%CI:10.19~ 22.59)年、2.61(95%CI:-0.61~5.82)年.高温和低温对≥65岁年龄组的影响明显大于<65岁年龄组.高温时,女性死亡率大于男性,男性的YLL大于女性;低温时,女性的死亡率和YLL均大于男性.结论重庆市高温和低温均可增加人群的死亡风险和YLL,≥65岁年龄组的人群更敏感,高温对年轻男性影响较大,低温对女性和老年男性影响较大,应有针对性保护极端温度敏感人群.%Objective To evaluate the influence of extreme ambient temperature on mortality and years of life lost (YLL) in Chongqing.Methods The daily mortality,meteorology and air pollution index data in Chongqing from the 1st January 2010 to the 31st December 2013 were

  1. Alterações na temperatura do ar mediante telas nas laterais de ambientes protegidos cultivados com tomateiro Changes in air temperature due to side screens of greenhouses cultivated with tomato

    Directory of Open Access Journals (Sweden)

    Larissa A Duarte

    2011-02-01

    Full Text Available Este trabalho avaliou a influência do uso de telas anti-insetos nas laterais de ambientes protegidos sobre a temperatura do ar de um cultivo de tomate. O experimento foi realizado em Itajaí, SC (27º 34' S; 48º 30' W, no período de 17/03 a 25/07/2003, onde foram instalados quatro ambientes cobertos com filme plástico de PEBD, sendo que um deles não possuía revestimento lateral e três estavam revestidos lateralmente, cada um com um tipo de tela anti-insetos. As telas anti-insetos utilizadas foram: clarite (5 fios por cm, citros (10 fios por cm e antiafídeo (20 fios por cm. O ambiente revestido com tela antiafídeo nas laterais apresentou maiores valores de temperatura máxima do ar durante o outono-inverno, o que ocasionou aumento médio de 2,0 °C na temperatura média diária, quando comparado com o ambiente sem tela nas laterais. A variação da temperatura do ar nos ambientes com tela citros e clarite foi semelhante, apresentando ganho térmico diário de 0,4 °C em relação ao ambiente sem tela anti-insetos e possibilitou condições mais estáveis entre as temperaturas noturna e diurna para o cultivo do tomateiro nessa época do ano.This study aims to assess the influence of insect-proof screens installed in plastic greenhouses cultivated with tomato on the air temperature and crop yield. The experiment was conducted in Itajaí, SC, Brazil (27º 34' S; 48º 30' W, from 17/03 to 25/07/2003. Four greenhouses cultivated with tomato and all covered with polyethylene of low density (PEBD in the superior part were used. Three of these environments were covered laterally, each one with a different kind of screen: clarite insect-proof screens (12 meshes per cm, citros insect-proof screens (25 meshes per cm and afideo insect-proof screens (50 meshes per cm. The fourth environment did not receive any side coverage. The covered environment with afideo insect-proof screens on sides presented the highest maximum air temperatures during the

  2. Evolución de huevos de Fasciola hepatica en el medio ambiente en Temuco,IX Región de Chile Development of Fasciola hepaticaeggs in outdoor temperatures in Temuco, southern Chile

    Directory of Open Access Journals (Sweden)

    G. VALENZUELA

    1998-01-01

    Full Text Available Se realizó un estudio de desarrollo de huevos de Fasciola hepatica en el medio ambiente en Temuco, Novena Región de Chile (38-41S y 72-25W. Las observaciones se realizaron desde abril de 1988 hasta junio de 1990. Los huevos obtenidos de vesículas de bovinos infectados con el parásito fueron colocados una vez al mes en vasos con agua destilada, en un sistema flotante. El sistema flotante se mantuvo en canales, en hábitat del parásito. Las muestras ueron examinadas una vez al mes hasta obtener el 50% de los huevos eclosionados. El tiempo de desarrollo más largo fue de 249 días en las muestras colocadas en abril de 1988 y el más corto, de 37 días, en las colocadas en enero de 1990. Los huevos colocados en el ambiente en marzo no eclosionaron hasta después del invierno, en octubre o noviembre. Se comprobó que los huevos no tienen un desarrollo paralelo. Se concluye que el desarrollo en el medio ambiente es influenciado por la temperatura ambiental, que varía de acuerdo a la latitud geográfica del hábitat, y que no hay eclosión de huevos a temperaturas medias inferiores a 10° C.A two-year study on the development of Fasciola hepatica eggs under outdoor conditions was carried out in Temuco, southern Chile (38-41S,72-25W. Eggs obtained from bile of infected cattle were placed in buckets in a medium of distilled water once a month, and examined at monthly intervals, until 50% had hatched. The shortest period of development was 37 days in eggs placed outside in January, 1990. The longest period required for development was 249 days for eggs placed outside in April 1988. Eggs placed outside in March failed to hatch in autumn and remained viable throughout the winter; most of them hatched in October or November. It was proved that liver fluke eggs do not have a parallel development and that the time taken to hatch vary within each sample. The hatching stage only occurred when the mean temperature was more than 10° C. It can be concluded

  3. 钛合金绝热剪切的敏感性分析及环境温度的影响%Analysis of Adiabatic Shear Sensitivity and Effect of Ambient Temperature for Titanium Alloy

    Institute of Scientific and Technical Information of China (English)

    王学滨

    2011-01-01

    通过引入与Batra及Kim类似的观点,将绝热剪切带宽度定义为绝热剪切带的中心区域的宽度(W5%),在该区域上温度比其峰值小5%,利用Johnson-cook模型及梯度塑性理论分析Ti-6A1-4V绝热剪切带的厚度随环境温度的演变规律.计算表明,随着环境温度的升高,绝热剪切带宽度增加,这与许多实验观测结果一致.当绝热剪切带的总厚度在上限时,绝热剪切带宽度-环境温度曲线是稍微上凹的;但是,当绝热剪切带的总厚度在下限时,绝热剪切带宽度-环境温度曲线基本上是直线,著名的Dodd及Bai模型无法预测这些新现象.关于绝热剪切带宽度的计算结果非常接近于Liao及Duffy的实测结果.在忽略应变硬化的条件下,采用线性软化模型及梯度塑性理论推导w5%的简化解析式,发现环境温度、密度、热容、软化模量、剪切应力的增加使绝热剪切的敏感性降低,而功热转化因子及抗剪强度的降低使绝热剪切的敏感性降低.%The Johnson-Cook model and gradient-dependent plasticity were used to investigate the adiabatic shear band (ASB) width and the ambient temperature effect for Ti-6Al-4V.The ASB width was defined as the width (w5%) of the region surrounding the band center over which the temperature differed from its peak value by less than 5%, which was similar to the viewpoint proposed by Batra and Kim.Theoretical results show that at higher ambient temperatures, the ASB is wider, as is in agreement with many experimental observations. At higher total ASB widths, the ASB width-ambient temperature curve is slightly concave-upward.However, at lower total ASB widths,the ASB width-ambient temperature curve is approximately linear.These new phenomena cannot be predicted by the famous Dodd and Bai's model.The calculated ASB widths are closer to the measured results by Liao and Duffy.A simple expression for the ASB width was derived under the condition of neglecting the strain

  4. O muco traqueobrônquico humano mantido em temperatura ambiente e suas propriedades físico-químicas Physicochemical properties of human tracheobronchial sputum maintained at room temperature

    Directory of Open Access Journals (Sweden)

    Renata Claudia Zanchet

    2007-02-01

    Full Text Available OBJETIVO: Verificar a influência da permanência em temperatura ambiente na análise da transportabilidade por ação ciliar e por tosse e do ângulo de contato do muco traqueobrônquico. MÉTODOS: Foi coletado muco hialino de 30 indivíduos sem doença pulmonar, e purulento de vinte pacientes com bronquiectasia. As amostras foram analisadas logo após a coleta e novamente após 24 h. RESULTADOS: Para o muco purulento, após 24 h em temperatura ambiente, houve aumento no deslocamento por tosse (96 ± 50 vs. 118 ± 61 mm e diminuição do ângulo de contato (32 ± 6 vs. 27 ± 6 graus (p OBJECTIVE: To evaluate the effect that maintaining tracheobronchial sputum at room temperature has on the analysis of ciliary transport and cough, as well as on the contact angle. METHODS: Hyaline sputum was collected from 30 individuals without pulmonary diseases, and purulent sputum was collected from patients with bronchiectasis. The samples were analyzed immediately after collection and again after 24 h. RESULTS: After 24 h at room temperature, the purulent sputum presented an increase in cough-induced dislodgment (96 ± 50 vs. 118 ± 61 mm and a decrease in the contact angle (32 ± 6 vs. 27 ± 6 degrees (p < 0.05. For the hyaline sputum, there were no alterations in the parameters analyzed. CONCLUSION: Hyaline tracheobronchial sputum can be stored in room temperature for 24 h without presenting alterations in ciliary transport or contact angle. However, purulent sputum should not be stored at room temperature for many hours, since ciliary transport and contact angle might be altered as a result.

  5. Fuel cells using ionic liquids as electrolyte and operating at room temperature; Celulas de combustivel utilizando como eletrolito liquidos ionicos e operando a temperatura ambiente

    Energy Technology Data Exchange (ETDEWEB)

    Botton, Janine Padilha; Souza, Roberto Fernando de; Goncalves, Reinaldo Simoes; Dupont, Jairton [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Inst. de Quimica], e-mail: janine@iq.ufrgs.br

    2004-07-01

    The room temperature imidazolium based ionic liquids, such as 1-n-butyl-3-methylimidazolium tetrafluoroborate (BMI.BF4) are outstanding electrolytes for fuel cells. A 67% overall cell efficiency is achieve using these liquids as supporting electrolytes for a commercially available alkaline fuel cell (AFC) at room temperature operating with air and hydrogen at atmospheric pressure. (author)

  6. Fracture and fatigue properties of Mo-Mo{sub 3}Si-Mo{sub 5}SiB{sub 2} refractory intermetallic alloys at ambient to elevated temperatures (25-1300 degrees Centigrade)

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Heeman; Schneibel, J.H.; Ritchie, R.O.

    2002-08-01

    The need for structural materials with high-temperature strength and oxidation resistance coupled with adequate lower-temperature toughness for potential use at temperatures above {approx} 1000 degrees C has remained a persistent challenge in materials science. In this work, one promising class of intermetallic alloys is examined, namely boron-containing molybdenum silicides, with compositions in the range Mo (bal), 12-17 at. percentSi, 8.5 at. percentB, processed using both ingot (I/M) and powder (P/M) metallurgy methods. Specifically, the oxidation (''pesting''), fracture toughness and fatigue-crack propagation resistance of four such alloys, which consisted of {approx}21 to 38 vol. percent a-Mo phase in an intermetallic matrix of Mo3Si and Mo5SiB2 (T2), were characterized at temperatures between 25 degrees and 1300 degrees C. The boron additions were found to confer superior ''pest'' resistance (at 400 degrees to 900 degrees C) as compared to unmodified molybdenum silicides, such as Mo5Si3. Moreover , although the fracture and fatigue properties of the finer-scale P/M alloys were only marginally better than those of MoSi2, for the I/M processed microstructures with coarse distributions of the a-Mo phase, fracture toughness properties were far superior, rising from values above 7 MPa sqrt m at ambient temperatures to almost 12 MPa sqrt m at 1300 degrees C.

  7. Psicologia do Ambiente

    OpenAIRE

    Antunes, Dalila; Bernardo, Fátima; Palma-Oliveira, José-Manuel

    2011-01-01

    Na aplicação da Psicologia à área do AMBIENTE importa em primeiro lugar definir o que se entende, neste contexto, por ambiente. O conceito é entendido como toda a envolvente que rodeia o ser humano. Referimo-nos pois ao espaço físico e aos estímulos que nele existem (som, ar, paisagem…), dirigindo-se a Psicologia do Ambiente ao estudo e intervenção sobre a forma como o ambiente influencia o indivíduo ou grupos, e sobre o modo como o comportamento dos indivíduos e grupos influenciam o ambiente...

  8. Atmosphere and Ambient Space

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    Atmosphere and Ambient Space This paper explores the relation between atmosphere and ambient space. Atmosphere and ambient space share many salient properties. They are both ontologically indeterminate, constantly varying and formally diffuse and they are both experienced as a subtle, non......-signifying property of a given space. But from a certain point of view, the two concepts also designate quite dissimilar experiences of space. To be ’ambient’ means to surround. Accordingly, ambient space is that space, which surrounds something or somebody. (Gibson 1987: 65) Since space is essentially...... of a surrounding character, all space can thus be described as having a fundamentally ambient character. So what precisely is an ambient space, then? As I will argue in my presentation, ambient space is a sensory effect of spatiality when a space is experienced as being particularly surrounding: a ‘space effect...

  9. Níveis de lisina digestível da ração e temperatura ambiente para frangos de corte em crescimento Dietary digestible lysine levels and environmental temperature for growing broiler chickens

    Directory of Open Access Journals (Sweden)

    Jefferson Costa de Siqueira

    2007-12-01

    Full Text Available Este estudo foi conduzido para avaliar os efeitos dos níveis de lisina digestível da ração e da temperatura ambiente sobre o desempenho e as características de carcaça de frangos de corte dos 22 a 42 dias de idade. Foram utilizados 672 frangos Ross®, machos, com peso médio de 726 g, em delineamento inteiramente casualizado segundo arranjo fatorial 4 × 4, com seis repetições de sete aves. Os frangos foram mantidos nas temperaturas de 18,5; 21,1; 24,5 e 27,0ºC e foram alimentados com rações com diferentes níveis de lisina digestível (0,934; 1,009; 1,084 e 1,159%. Não houve interação temperatura ambiente × níveis de lisina da ração para as variáveis estudadas. O consumo de ração (CR e o ganho de peso (GP não foram influenciados pelos níveis de lisina. O consumo de ração reduziu linearmente com a temperatura ambiente e o ganho de peso aumentou até a temperatura estimada de 21,5ºC. A conversão alimentar melhorou até o nível estimado de 1,085% de lisina digestível. Os pesos de carcaça (PC, peito com osso (PPO, coxa (PCX e sobrecoxa (PSCX aumentaram até as temperaturas estimadas de 21,9; 21,0; 22,7 e 23,7ºC, respectivamente. Os rendimentos de carcaça (RC, coxa (RCX e sobrecoxa (RSCX aumentaram, enquanto o peso do peito sem osso (PPSO e os rendimentos de peito com osso (RPO e sem osso (RPSO reduziram linearmente com a temperatura ambiente. O PCX e o RCX aumentaram, mas o RSCX reduziu linearmente com os níveis de lisina da ração. O PC, PPO, PSCX, RC, RPO e o RPSO não foram influenciados pelos níveis de lisina. A temperatura ambiente no intervalo de 18,5 e 27,0ºC não influenciou as exigências de lisina das aves. A condição para melhor conversão alimentar no período de 22 a 42 dias foi obtida com o nível de 1,085% de lisina digestível na ração e com a temperatura ambiente estimada de 23,3ºC.This study was aimed to evaluate the effects of the dietary digestible lysine levels and environmental

  10. 不同环境温度和活动强度下人体出汗率测定%The Measurement of Sweat Rate under Different Ambient Temperature and Activity Intensity

    Institute of Scientific and Technical Information of China (English)

    魏洋; 王革辉

    2011-01-01

    A new method which was called clothing weight gain was put forward for measuring the amount of sweat produced by human body. With this method the amount of sweat produced by human body was measured after 8 subjects ran on a treadmill for 15 min at speeds of 2,4,6mi/b (54, 107, 161 m/rain) and in the ambient temperature of 20, 25, 28℃ respectively. By carrying out paired-samples t test, the measurement results of sweat rate were analyzed. It was found that both ambient temperature and activity intensity had significant effects on sweat rate per unit area. When the ambient temperature was 20, 25, 28 ℃ and activity intensity was 2, 4, 6mi/h respectively, the sweat rate per unit area was in the range of 1.605-681.100 g/(h· m^2) .%提出了一种测定人体出汗量的方法一衣物增重法,并利用该法分别测定20、25、28℃环境温度下.8名受试者在跑步机上分别以2、4、6mi/h(54、107、161m/min)的速度跑步15min后的出汗量。运用配对样本t检验,并对出汗率测定结果进行分析后发现,环境温度和活动强度对人体单位面积出汗率均有显著影响。环境温度分别为20、25、28℃以及活动强度分别为2、4、6mi/h时,人体单位面积出汗率的范围为1.605-681.100g/(h·m^2)。

  11. Influence of ambient temperature on hibernation patterns and energy consumption in Daurian ground squirrels (Spermophilus dauricus)%环境温度对达乌尔黄鼠冬眠模式和能量消耗的影响

    Institute of Scientific and Technical Information of China (English)

    于超; 宋士一; 彭霞; 杨明

    2014-01-01

    In order to research the inflience of the ambient temperature on animals during hibernation,we used iButtons to monitor the body temperatures in winter,hibernation patterns and energy consumption of Daurian ground squirrels under different ambient temperature ((5±2)℃,(15±2)℃,(25±2)℃)in laboratory.Under different ambient temperature,the hibernation patterns and energy consumption in Daurian ground squirrels were significantly diversified. At 5 ℃,animals all showed deep hibernation.At 15 ℃,both deep hibernation and short hibernation were showed.At 25℃,the more deep hibernation and the lesss no hibernation were behaved.When the temperatuer was at 5 ℃,1 5 ℃ and 25 ℃ during hibernation,the total energy consumption was respectively (3 722±217.82)kJ,(18 907±2 895.07)kJ and (30 542±2 146.40)kJ.The diversity was significant(F(2,22)=45.198,P=0<0.01).From the view of energetics,the high ambient temperature is not conducive to spend winter for hibernation animals in hibernation season.%为研究环境温度对动物冬眠的影响,在实验室不同环境温度下((5±2)℃,(15±2)℃,(25±2)℃)用植入式半导体元件记录了达乌尔黄鼠冬季的体温,监测了冬眠模式及能量消耗。结果显示环境温度不同时,达乌尔黄鼠冬眠的模式和能量消耗均有显著差异。在5℃下,动物均表现为深冬眠型;15℃下,动物表现为深冬眠型和少冬眠型;25℃环境下动物表现为较多少冬眠型和少量不冬眠型。在5、15和25℃冬眠期间总能量消耗分别为(3722±217.82) kJ,(18907±2895.07)kJ,(30542±2146.40)kJ,差异显著(F(2,22)=45.198,P=0<0.01)。提示在冬眠动物的冬眠季节,从能量学角度来看,高的环境温度并不利于动物的越冬。

  12. Effects of living at two ambient temperatures on 24-h blood pressure and neuroendocrine function among obese and non-obese humans: a pilot study

    Science.gov (United States)

    Kanikowska, Dominika; Sato, Maki; Iwase, Satoshi; Shimizu, Yuuki; Nishimura, Naoki; Inukai, Yoko; Sugenoya, Junichi

    2013-05-01

    The effects of environmental temperature on blood pressure and hormones in obese subjects in Japan were compared in two seasons: summer vs winter. Five obese (BMI, 32 ± 5 kg/m2) and five non-obese (BMI, 23 ±3 kg/m2) men participated in this experiment at latitude 35°10' N and longitude 136°57.9' E. The average environmental temperature was 29 ± 1 °C in summer and 3 ± 1 °C in winter. Blood samples were analyzed for leptin, ghrelin, catecholamines, thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), total cholesterol, triglycerides, insulin and glucose. Blood pressure was measured over the course of 24 h in summer and winter. A Japanese version of the Profile of Mood States (POMS) questionnaire was also administered each season. Systolic and diastolic blood pressures in obese men were significantly higher in winter (lower environmental temperatures) than in summer (higher environmental temperatures). Noradrenaline and dopamine concentrations were also significantly higher at lower environmental temperatures in obese subjects, but ghrelin, TSH, fT3, fT4, insulin and glucose were not significantly different in summer and winter between obese and non-obese subjects. Leptin, total cholesterol and triglyceride concentrations were significantly higher in winter in obese than non-obese men. Results from the POMS questionnaire showed a significant rise in Confusion at lower environmental temperatures (winter) in obese subjects. In this pilot study, increased blood pressure may have been due to increased secretion of noradrenaline in obese men in winter, and the results suggest that blood pressure control in obese men is particularly important in winter.

  13. The influence of methanol on the chemical state of PtRu anodes in a high-temperature direct methanol fuel cell studied in situ by synchrotron-based near-ambient pressure x-ray photoelectron spectroscopy

    Science.gov (United States)

    Saveleva, Viktoriia A.; Daletou, Maria K.; Savinova, Elena R.

    2017-01-01

    Synchrotron radiation-based near-ambient pressure x-ray photoelectron spectroscopy (NAP-XPS) has recently become a powerful tool for the investigation of interfacial phenomena in electrochemical power sources such as batteries and fuel cells. Here we present an in situ NAP-XPS study of the anode of a high-temperature direct methanol fuel cell with a phosphoric acid-doped hydrocarbon membrane, which reveals an enhanced flooding of the Pt3Ru anode with phosphoric acid in the presence of methanol. An analysis of the electrode surface composition depending on the cell voltage and on the presence of methanol reveals the strong influence of the latter on the extent of Pt oxidation and on the transformation of Ru into Ru (IV) hydroxide.

  14. CsF mediated rapid condensation of 1,3-cyclohexadione with aromatic aldehydes: Comparative study of conventional heating vs.ambient temperature

    Institute of Scientific and Technical Information of China (English)

    Kamalakar P. Nandre; Vijay S. Patil; Sidhanath V. Bhosale

    2011-01-01

    A mild, efficient and high yielding protocol for the synthesis of 2,2'-arylmethelene dicyclohexane-1,3-dione derivatives at room temperature and 9-aryl-l,8-dihydrooctahydroxanthene at conventional heating using cesium fluoride as a catalyst is reported. The major advantages of this reaction are excellent yield, very short reaction time and use of inexpensive catalyst.

  15. Effect of Vaporizer Temperature on Ambient Non-Refractory Submicron Aerosol Composition and Mass Spectra Measured by the Aerosol Mass Spectrometer

    Science.gov (United States)

    Aerodyne Aerosol Mass Spectrometers (AMS) are routinely operated with a constant vaporizer temperature (Tvap) of 600oC in order to facilitate quantitative detection of non-refractory submicron (NR-PM1) species. By analogy with other thermal desorption instrument...

  16. Moisture rivals temperature in limiting photosynthesis by trees establishing beyond their cold-edge range limit under ambient and warmed conditions

    Science.gov (United States)

    Moyes, Andrew B.; Germino, Matthew J.; Kueppers, Lara M.

    2015-01-01

    Climate change is altering plant species distributions globally, and warming is expected to promote uphill shifts in mountain trees. However, at many cold-edge range limits, such as alpine treelines in the western United States, tree establishment may be colimited by low temperature and low moisture, making recruitment patterns with warming difficult to predict.

  17. Application of nano SnO2 as a green and recyclable catalyst for the synthesis of 2-aryl or alkylbenzoxazole derivatives under ambient temperature

    Indian Academy of Sciences (India)

    Seyed Mohammad Vahdat; Shima Ghafouri Raz; Saeed Baghery

    2014-05-01

    Application of nano SnO2 as an efficient and benign catalyst has been explored for the synthesis of 2-aryl or alkylbenzoxazole derivatives via condensation reaction of aldehyde with 2-aminophenol. The reactions proceed under heterogeneous and mild conditions in ethanol at room temperature to provide 2-aryl or alkylbenzoxazoles in high yields.

  18. Moisture rivals temperature in limiting photosynthesis by trees establishing beyond their cold-edge range limit under ambient and warmed conditions.

    Science.gov (United States)

    Moyes, Andrew B; Germino, Matthew J; Kueppers, Lara M

    2015-09-01

    Climate change is altering plant species distributions globally, and warming is expected to promote uphill shifts in mountain trees. However, at many cold-edge range limits, such as alpine treelines in the western United States, tree establishment may be colimited by low temperature and low moisture, making recruitment patterns with warming difficult to predict. We measured response functions linking carbon (C) assimilation and temperature- and moisture-related microclimatic factors for limber pine (Pinus flexilis) seedlings growing in a heating × watering experiment within and above the alpine treeline. We then extrapolated these response functions using observed microclimate conditions to estimate the net effects of warming and associated soil drying on C assimilation across an entire growing season. Moisture and temperature limitations were each estimated to reduce potential growing season C gain from a theoretical upper limit by 15-30% (c. 50% combined). Warming above current treeline conditions provided relatively little benefit to modeled net assimilation, whereas assimilation was sensitive to either wetter or drier conditions. Summer precipitation may be at least as important as temperature in constraining C gain by establishing subalpine trees at and above current alpine treelines as seasonally dry subalpine and alpine ecosystems continue to warm.

  19. Effects of ambient air temperature, humidity, and wind speed on seminal traits in Braford and Nellore bulls at the Brazilian Pantanal

    Science.gov (United States)

    Menegassi, Silvio Renato Oliveira; Pereira, Gabriel Ribas; Bremm, Carolina; Koetz, Celso; Lopes, Flávio Guiselli; Fiorentini, Eduardo Custódio; McManus, Concepta; Dias, Eduardo Antunes; da Rocha, Marcela Kuczynski; Lopes, Rubia Branco; Barcellos, Júlio Otávio Jardim

    2016-11-01

    The aim of this study was to evaluate the bioclimatic thermal stress assessed by Equivalent Temperature Index (ETI) and Temperature Humidity Index (THI) on Braford and Nellore bulls sperm quality during the reproductive seasons at the tropical region in the Brazilian Pantanal. We used 20 bulls aged approximately 24 months at the beginning of the study. Five ejaculates per animal were collected using an electroejaculator. Temperature, air humidity, and wind speed data were collected every hour from the automatic weather station at the National Institute of Meteorology. Infrared thermography images data were collected to assess the testicular temperature gradient in each animal. Data were analyzed with ANOVA using MIXED procedure of SAS and means were compared using Tukey's HSD test. The THI and ETI at 12 days (epididymal transit) were higher in January (89.7 and 28.5, respectively) and February (90.0 and 29.0, respectively) compared to other months ( P animals. Reproductive response to environmental changes is a consequence of Nellore and Braford adaptation to climate stress conditions. Both THI and ETI environmental indexes can be used to evaluate the morphological changes in the seminal parameters in Nellore or Braford bulls; however, more experiments should be performed focusing on larger sample numbers and also in reproductive assessment during the consecutive years to assess fertility potential.

  20. Donor Acceptor Polymerization Chemistry as a Vehicle to Low Energy Cure of Matrix Resins: Evolution of the 2-Tg Concept to Produce High Tg Polymers at Ambient Temperatures

    Science.gov (United States)

    1989-03-01

    tetrafunctional acceptors. DSC and TGA analysis of these polymers indicated they possessed the thermal stability necessary for performance in their...be enhanced by choosing comonomers that act as "solvents", and that the "onset of decomposition" temperature as measured by TGA analysis under nitrogen

  1. Influence of {gamma}-{alpha}'-phase transformation in metastable austenitic steels on the mechanical behavior during tensile and fatigue Loading at ambient and lower temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Hahnenberger, Frank; Smaga, Marek; Eifler, Dietmar [Institute of Materials Science and Engineering, University of Kaiserslautern, P.O. Box 3049, 67653 Kaiserslautern (Germany)

    2012-10-15

    The present investigation is concerned with the three metastable austenitic steels AISI 304 (X5CrNi1810), 321 (X6CrNiTi1810), and 348 (X10CrNiNb189). In the temperature range -60 C {<=} T {<=} 25 C tensile and fatigue tests were performed to characterize the mechanical and phase transformation behavior using stress-elongation, stress-strain hysteresis, and magnetic measurements. The mechanical properties are significantly influenced by the temperature dependent deformation induced phase transformation from austenite to {alpha}'-martensite which are combined with pronounced hardening processes. Furthermore microhardness measurements after fracture could be correlated with the results of the fatigue tests. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Toward ambient temperature operation with all-solid-state lithium metal batteries with a sp3 boron-based solid single ion conducting polymer electrolyte

    Science.gov (United States)

    Zhang, Yunfeng; Cai, Weiwei; Rohan, Rupesh; Pan, Meize; Liu, Yuan; Liu, Xupo; Li, Cuicui; Sun, Yubao; Cheng, Hansong

    2016-02-01

    The ionic conductivity decay problem of poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) when increase the lithium salt of the SPEs up to high concentration is here functionally overcome by the incorporation of a charge delocalized sp3 boron based single ion conducting polymer electrolyte (SIPE) with poly(ethylene oxide) to fabricate solid-state sp3 boron based SIPE membranes (S-BSMs). By characterizations, particularly differential scanning calorimeter (DSC) and ionic conductivity studies, the fabricated S-BSMs showed decreased melting points and increased ionic conductivity as steadily increase the content of sp3 boron based SIPE, which significantly improved the low temperature performance of the all-solid-state lithium batteries. The fabricated Li | S-BSMs | LiFePO4 cells exhibit highly electrochemical stability and excellent cycling at temperature below melting point of PEO, which has never been reported so far for SIPEs based all-solid-state lithium batteries.

  3. Influence of sample return time and ambient temperature on the performance of an immunochemical faecal occult blood test with a new buffer for colorectal cancer screening.

    Science.gov (United States)

    Dancourt, Vincent; Hamza, Samia; Manfredi, Sylvain; Drouillard, Antoine; Bidan, Jeanne-Marie; Faivre, Jean; Lepage, Come

    2016-03-01

    The haemoglobin concentration measured by faecal immunochemical tests (FIT) may be decreased in cases of delayed sample return or high temperature. It is an issue of great importance. The aim of this study was to investigate the effects of sample return time and of season on the performance of an FIT (FOB-Gold) with a new buffer. The study included 20 371 participants involved in the French organized colorectal cancer (CRC) screening programme. The probability of a positive screening test, detection rates and positive predictive values for CRC and advanced adenoma were analysed according to sample return time and season of screening. A sample of positive FIT was stored for 7 days in an incubator at 20°C or 30°C. The positivity rate was 4.1% for a sample return time of up to 3 days, 4.1% for 4-5 days and 4.6% for 6-7 days (P=0.25). In multivariate analysis, there was no association between positivity rates, detection rates and positive predictive values for CRC and advanced adenoma and the sample return time or the season of screening. At a constant temperature of 20°C, there was a decrease in the haemoglobin concentration of 5.1% after 7 days. The decrease reached 20.5% at a temperature of 30°C. It was only 4.5% during the first 4 days of storage in the incubator. With the new buffer, delay in sample return or season did not affect the clinical outcome. When temperatures reach 30°C, the faecal sample must be returned promptly.

  4. Effects of ambient air temperature, humidity, and wind speed on seminal traits in Braford and Nellore bulls at the Brazilian Pantanal

    Science.gov (United States)

    Menegassi, Silvio Renato Oliveira; Pereira, Gabriel Ribas; Bremm, Carolina; Koetz, Celso; Lopes, Flávio Guiselli; Fiorentini, Eduardo Custódio; McManus, Concepta; Dias, Eduardo Antunes; da Rocha, Marcela Kuczynski; Lopes, Rubia Branco; Barcellos, Júlio Otávio Jardim

    2016-04-01

    The aim of this study was to evaluate the bioclimatic thermal stress assessed by Equivalent Temperature Index (ETI) and Temperature Humidity Index (THI) on Braford and Nellore bulls sperm quality during the reproductive seasons at the tropical region in the Brazilian Pantanal. We used 20 bulls aged approximately 24 months at the beginning of the study. Five ejaculates per animal were collected using an electroejaculator. Temperature, air humidity, and wind speed data were collected every hour from the automatic weather station at the National Institute of Meteorology. Infrared thermography images data were collected to assess the testicular temperature gradient in each animal. Data were analyzed with ANOVA using MIXED procedure of SAS and means were compared using Tukey's HSD test. The THI and ETI at 12 days (epididymal transit) were higher in January (89.7 and 28.5, respectively) and February (90.0 and 29.0, respectively) compared to other months (P < 0.01). Total seminal defects differ only in Bradford bulls between the months of November and February. Nellore bulls had lower major defects (MaD) and total defects (TD) compared to Braford. Nellore bulls showed correlation between minor defects (MiD) and THI for 30 days (0.90) and 18 days (0.88; P < 0.05). Braford bulls showed correlation for MaD (0.89) in ETI for 12 days (P < 0.05). Infrared thermography showed no difference between animals. Reproductive response to environmental changes is a consequence of Nellore and Braford adaptation to climate stress conditions. Both THI and ETI environmental indexes can be used to evaluate the morphological changes in the seminal parameters in Nellore or Braford bulls; however, more experiments should be performed focusing on larger sample numbers and also in reproductive assessment during the consecutive years to assess fertility potential.

  5. Effects of Ambient Air and Temperature on Ionic Gel Gated Single-Walled Carbon Nanotube Thin-Film Transistor and Circuits.

    Science.gov (United States)

    Li, Huaping; Zhou, Lili

    2015-10-21

    Single-walled carbon nanotube thin-film transistor (SWCNT TFT) and circuits were fabricated by fully inkjet printing gold nanoparticles as source/drain electrodes, semiconducting SWCNT thin films as channel materials, PS-PMMA-PS/EMIM TFSI composite gel as gate dielectrics, and PEDOT/PSS as gate electrodes. The ionic gel gated SWCNT TFT shows reversible conversion from p-type transistor behavior in air to ambipolar features under vacuum due to reversible oxygen doping in semiconducting SWCNT thin films. The threshold voltages of ionic gel gated SWCNT TFT and inverters are largely shifted to the low value (0.5 V for p-region and 1.0 V for n-region) by vacuum annealing at 140 °C to exhausively remove water that is incorporated in the ionic gel as floating gates. The vacuum annealed ionic gel gated SWCNT TFT shows linear temperature dependent transconductances and threshold voltages for both p- and n-regions. The strong temperature dependent transconductances (0.08 μS/K for p-region, 0.4 μS/K for n-region) indicate their potential application in thermal sensors. In the other hand, the weak temperature dependent threshold voltages (-1.5 mV/K for p-region, -1.1 mV/K for n-region) reflect their excellent thermal stability.

  6. Ambient-temperature NO oxidation over amorphous CrOx-ZrO2 mixed oxide catalysts: Significant promoting effect of ZrO2

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Aiyong; Guo, Yanglong; Gao, Feng; Peden, Charles H. F.

    2017-03-01

    Three series of Cr-based mixed oxides (Cr-Co, Cr-Fe, and Cr-Ni oxides) with high specific surface areas and amorphous textures are synthesized using a novel sol-gel method. These mixed oxides, in comparison to their pure metal oxide (CrOx, Co3O4, FeOx and NiO) counterparts, display enhanced performance for catalytic oxidation of low-concentration NO at room temperature. Over best performing catalysts, 100% NO conversion can be maintained up to 30 h of operation at a high space velocity of 45,000 ml g-1 h-1. The amorphous structure is found to be critical for these catalysts to maintain high activity and durability. Cr/M (M=Co, Fe and Ni) molar ratio, nitrate precursor decomposition temperature and catalyst calcination temperature are important criteria for the synthesis of the highly active catalysts. This work was supported by National Basic Research Program of China (2013CB933200), National Natural Science Foundation of China (21577035, 21577034), Commission of Science and Technology of Shanghai Municipality (15DZ1205305) and 111 Project (B08021). Aiyong Wang gratefully acknowledges the China Scholarship Council for the Joint-Training Scholarship Program with the Pacific Northwest National Laboratory (PNNL). PNNL is operated for the U.S. Department of Energy (DOE) by Battelle. FG and CHFP are supported by the U.S. DOE/Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office.

  7. DERECHO AMBIENTAL EN ARGENTINA

    OpenAIRE

    2014-01-01

    El objetivo de la presente publicación es brindar un panorama general, introductorio y actualizado del derecho ambiental argentino. Entendiendo que el derecho ambiental es un signo de nuestra era y que por la dinamicidad de la cuestión ambiental requiere de permanente actualización regularoria. La autora desarrolla en forma objetiva su postura en relación con la necesidad de hacer sostenible al derecho ambiental. Para luego analizar brevemente la situación actual del derecho vigente en Argent...

  8. Influence of Constant High Ambient Temperature on Fat Metabolism of Different Parts in Finishing Pigs%持续高温对育肥猪不同部位脂肪代谢的影响

    Institute of Scientific and Technical Information of China (English)

    吴鑫; 冯京海; 张敏红; 苏红光; 贾安峰

    2015-01-01

    [Objective] The objective of this study is to investigate the effects of constant high ambient temperature on fat metabolism in finishing pigs and to preliminarily explore the mechanism of the impact.[Method] Sixteen Duroc × Landrace × Large White castrated male pigs were randomly assigned into a high-temperature environment (HT group: 30℃,ad libtum) and a normal thermal group (NT group: 22℃,ad libtum) with eight pigs in each treatment. Pigs were housed in individual wire cages under a 14-h lighting schedule and had free access to water. The experiment lasted for 3 weeks, and the temperature kept unchanged during this time. The relative humidity in the room was controlled at (55±5)%. The pigs were electrically stunned and exsanguinated after a 12-h period of feed withdrawal with free access to water at the end of the experiment.[Result] The results of the experiment showed that the carcass weight and backfat depth at 30℃ were lower than that at 22℃, but the differences were not significant (P>0.10). And high ambient temperature had a trend to increase the proportion of flare fat in carcass weight (+22.06%,P=0.07), to decrease the lipid content of longissimus dorsi (LM) (-22.39%,P=0.08). The activities of fatty acid synthase (FAS) (P0.10). High ambient temperature significantly increased the content of LPL in flare fat (P=0.05), and decreased the content of LPL in LM (P=0.05). The rule how high ambient temperature influenced fat deposition of the three parts was in accordance with the rule how high ambient temperature influenced the contents of LPL in the same part, which means that high ambient temperature may influence the fat deposition by regulating the content of LPL. The activities ofβ-hydroxyacyl coenzyme A dehydrogenase (HAD) at the front (P0.10). The plasma concentration of nonesterified fatty acid (NEFA) was higher (P0.10).[Conclusion]The results demonstrated that high ambient temperature had different effects on adipose tissues in different

  9. High Temperature, High Ambient CO₂ Affect the Interactions between Three Positive-Sense RNA Viruses and a Compatible Host Differentially, but not Their Silencing Suppression Efficiencies.

    Directory of Open Access Journals (Sweden)

    Francisco J Del Toro

    Full Text Available We compared infection of Nicotiana benthamiana plants by the positive-sense RNA viruses Cucumber mosaic virus (CMV, Potato virus Y (PVY, and by a Potato virus X (PVX vector, the latter either unaltered or expressing the CMV 2b protein or the PVY HCPro suppressors of silencing, at 25°C vs. 30°C, or at standard (~401 parts per million, ppm vs. elevated (970 ppm CO2 levels. We also assessed the activities of their suppressors of silencing under those conditions. We found that at 30°C, accumulation of the CMV isolate and infection symptoms remained comparable to those at 25°C, whereas accumulation of the PVY isolate and those of the three PVX constructs decreased markedly, even when expressing the heterologous suppressors 2b or HCPro, and plants had either very attenuated or no symptoms. Under elevated CO2 plants grew larger, but contained less total protein/unit of leaf area. In contrast to temperature, infection symptoms remained unaltered for the five viruses at elevated CO2 levels, but viral titers in leaf disks as a proportion of the total protein content increased in all cases, markedly for CMV, and less so for PVY and the PVX constructs. Despite these differences, we found that neither high temperature nor elevated CO2 prevented efficient suppression of silencing by their viral suppressors in agropatch assays. Our results suggest that the strength of antiviral silencing at high temperature or CO2 levels, or those of the viral suppressors that counteract it, may not be the main determinants of the observed infection outcomes.

  10. An Efficient, Simple and Green Zn(Phen2Cl2 Complex Catalyzed Synthesis of 4-H-Benzo[b]pyrans in Water at Ambient Temperature

    Directory of Open Access Journals (Sweden)

    E. Mosaddegh

    2011-01-01

    Full Text Available An efficient method for the synthesis of 4-H-benzo[b]pyrans has been developed by the use of Zn(Phen2Cl2(2 mol% as an ecofriendly catalyst. The mixture of an appropriate aldehyde, malononitrile and dimedone in the presence of the Zn(Phen2Cl2 as an inorganic catalyst in water at room temperature resulted excellent yields of the corresponding products in 5 min. Very short experimental time of the reaction, excellent yields, use of water as a green solvent, simple work-up and uses no extra catalyst and purification are the advantages of this method.

  11. Efficient catalytic interconversion between NADH and NAD+ accompanied by generation and consumption of hydrogen with a water-soluble iridium complex at ambient pressure and temperature.

    Science.gov (United States)

    Maenaka, Yuta; Suenobu, Tomoyoshi; Fukuzumi, Shunichi

    2012-01-11

    Regioselective hydrogenation of the oxidized form of β-nicotinamide adenine dinucleotide (NAD(+)) to the reduced form (NADH) with hydrogen (H(2)) has successfully been achieved in the presence of a catalytic amount of a [C,N] cyclometalated organoiridium complex [Ir(III)(Cp*)(4-(1H-pyrazol-1-yl-κN(2))benzoic acid-κC(3))(H(2)O)](2) SO(4) [1](2)·SO(4) under an atmospheric pressure of H(2) at room temperature in weakly basic water. The structure of the corresponding benzoate complex Ir(III)(Cp*)(4-(1H-pyrazol-1-yl-κN(2))-benzoate-κC(3))(H(2)O) 2 has been revealed by X-ray single-crystal structure analysis. The corresponding iridium hydride complex formed under an atmospheric pressure of H(2) undergoes the 1,4-selective hydrogenation of NAD(+) to form 1,4-NADH. On the other hand, in weakly acidic water the complex 1 was found to catalyze the hydrogen evolution from NADH to produce NAD(+) without photoirradiation at room temperature. NAD(+) exhibited an inhibitory behavior in both catalytic hydrogenation of NAD(+) with H(2) and H(2) evolution from NADH due to the binding of NAD(+) to the catalyst. The overall catalytic mechanism of interconversion between NADH and NAD(+) accompanied by generation and consumption of H(2) was revealed on the basis of the kinetic analysis and detection of the catalytic intermediates.

  12. PRESERVATION OF H2 PRODUCTION ACTIVITY IN NANOPOROUS LATEX COATINGS OF RHODOPSEUDOMONAS PALUSTRIS CGA009 DURING DRY STORAGE AT AMBIENT TEMPERATURES

    Energy Technology Data Exchange (ETDEWEB)

    Milliken, C.; Piskorska, M.; Soule, T.; Gosse, J.; Flickinger, M.; Smith, G.; Yeager, C.

    2012-08-27

    To assess the applicability of latex cell coatings as an "off-the-shelf' biocatalyst, the effect of osmoprotectants, temperature, humidity and O{sub 2} on preservation of H{sub 2} production in Rhodopseudomonas palustris coatings was evaluated. Immediately following latex coating coalescence (24 h) and for up to 2 weeks of dry storage, rehydrated coatings containing different osmoprotectants displayed similar rates of H{sub 2} production. Beyond 2 weeks of storage, sorbitol- treated coatings lost all H{sub 2} production activity, whereas considerable H{sub 2} production was still detected in sucrose- and trehalose-stabilized coatings. The relative humidity level at which the coatings were stored had a significant impact on the recovery and subsequent rates of H{sub 2} production. After 4 weeks storage under air at 60% humidity, coatings produced only trace amounts of H{sub 2} (0-0.1% headspace accumulation), whereas those stored at <5% humidity retained 27-53% of their H{sub 2} production activity after 8 weeks of storage. When stored in argon at <5% humidity and room temperature, R. palustris coatings retained full H{sub 2} production activity for 3 months, implicating oxidative damage as a key factor limiting coating storage. Overall, the results demonstrate that biocatalytic latex coatings are an attractive cell immobilization platform for preservation of bioactivity in the dry state.

  13. Radiactividad y medio ambiente

    OpenAIRE

    Sánchez León, José Guillermo

    1993-01-01

    En los medios de comunicación frecuentemente aparecen noticias que hacen referencia a la radiactividad y al medio ambiente y, sin embargo, lo que es la radiactividad y como influye ésta sobre el medio ambiente suele ser poco conocido, incluso por personas de formación científica.

  14. Response of laying hens to feeding low-protein amino acid-supplemented diets under high ambient temperature: performance, egg quality, leukocyte profile, blood lipids, and excreta pH.

    Science.gov (United States)

    Torki, Mehran; Mohebbifar, Ahmad; Ghasemi, Hossein Ali; Zardast, Afshin

    2015-05-01

    An experiment was conducted to determine whether, by using a low-protein amino acid-supplemented diet, the health status, stress response, and excreta quality could be improved without affecting the productive performance of heat-stressed laying hens. The requirements for egg production, egg mass, and feed conversion ratio were also estimated using second-order equations and broken-line regression. A total of 150 Lohmann Selected Leghorn (LSL-Lite) hens were divided randomly into five groups of 30 with five replicates of six hens. The hens were raised for an 8-week period (52 to 60 weeks) in wire cages situated in high ambient temperature in an open-sided housing system. The five experimental diets (ME; 2,720 kcal/kg) varied according to five crude protein (CP) levels: normal-CP diet (control, 16.5 % CP) and low-CP diets containing 15.0, 13.5, 12.0, or 10.5 % CP. All experimental diets were supplemented with crystalline amino acids at the levels sufficient to meet their requirements. The results showed that under high temperature conditions, all productive performance and egg quality parameters in the birds fed with 15.0, 13.5, and 12.0 % CP diets were similar to those of birds fed with control diet (16.5 % CP), whereas feeding 10.5 % CP diet significantly decreased egg production and egg mass. Estimations of requirements were of 13.93 and 12.77 % CP for egg production, 14.62 and 13.22 % CP for egg mass, and 12.93 and 12.26 % CP for feed conversion ratio using quadratic and broken-line models, respectively. Egg yolk color index, blood triglyceride level, and excreta acidity were also significantly higher in birds fed with 12.0 and 10.5 % CP diets compared with those of control birds. The heterophil to lymphocyte ratio, as a stress indicator, was significantly decreased by 15.0, 13.5, and 12 % CP diets. On the basis of our findings, reducing dietary CP from 16.5 to 12.0 % and supplementing the diets with the essential amino acids showed merit for improving the

  15. Response of laying hens to feeding low-protein amino acid-supplemented diets under high ambient temperature: performance, egg quality, leukocyte profile, blood lipids, and excreta pH

    Science.gov (United States)

    Torki, Mehran; Mohebbifar, Ahmad; Ghasemi, Hossein Ali; Zardast, Afshin

    2015-05-01

    An experiment was conducted to determine whether, by using a low-protein amino acid-supplemented diet, the health status, stress response, and excreta quality could be improved without affecting the productive performance of heat-stressed laying hens. The requirements for egg production, egg mass, and feed conversion ratio were also estimated using second-order equations and broken-line regression. A total of 150 Lohmann Selected Leghorn (LSL-Lite) hens were divided randomly into five groups of 30 with five replicates of six hens. The hens were raised for an 8-week period (52 to 60 weeks) in wire cages situated in high ambient temperature in an open-sided housing system. The five experimental diets (ME; 2,720 kcal/kg) varied according to five crude protein (CP) levels: normal-CP diet (control, 16.5 % CP) and low-CP diets containing 15.0, 13.5, 12.0, or 10.5 % CP. All experimental diets were supplemented with crystalline amino acids at the levels sufficient to meet their requirements. The results showed that under high temperature conditions, all productive performance and egg quality parameters in the birds fed with 15.0, 13.5, and 12.0 % CP diets were similar to those of birds fed with control diet (16.5 % CP), whereas feeding 10.5 % CP diet significantly decreased egg production and egg mass. Estimations of requirements were of 13.93 and 12.77 % CP for egg production, 14.62 and 13.22 % CP for egg mass, and 12.93 and 12.26 % CP for feed conversion ratio using quadratic and broken-line models, respectively. Egg yolk color index, blood triglyceride level, and excreta acidity were also significantly higher in birds fed with 12.0 and 10.5 % CP diets compared with those of control birds. The heterophil to lymphocyte ratio, as a stress indicator, was significantly decreased by 15.0, 13.5, and 12 % CP diets. On the basis of our findings, reducing dietary CP from 16.5 to 12.0 % and supplementing the diets with the essential amino acids showed merit for improving the

  16. DERECHO AMBIENTAL EN ARGENTINA

    Directory of Open Access Journals (Sweden)

    Silvia Nonna

    2014-05-01

    Full Text Available El objetivo de la presente publicación es brindar un panorama general, introductorio y actualizado del derecho ambiental argentino. Entendiendo que el derecho ambiental es un signo de nuestra era y que por la dinamicidad de la cuestión ambiental requiere de permanente actualización regulatoria. La autora desarrolla en forma objetiva su postura en relación con la necesidad de hacer sostenible al derecho ambiental. Para luego analizar brevemente la situación actual del derecho vigente en Argentina, haciendo un rápido y resumido recorrido desde la última reforma de la Constitución Nacional hasta la consideración especial de cada una de las nuevas normas de presupuestos mínimos de protección ambiental.

  17. Facile preparation of N-doped TiO2 at ambient temperature and pressure under UV light with 4-nitrophenol as the nitrogen source and its photocatalytic activities.

    Science.gov (United States)

    Horikoshi, Satoshi; Shirasaka, Yutaro; Uchida, Hiroshi; Horikoshi, Natsuko; Serpone, Nick

    2016-08-04

    To date syntheses of nitrogen-doped TiO2 photocatalysts (TiO2-xNx) have been carried out under high temperatures and high pressures with either NH3 or urea as the nitrogen sources. This article reports for the first time the facile preparation of N-doped TiO2 (P25 titania) in aqueous media at ambient temperature and pressure under inert conditions (Ar- and N2-purged dispersions) with 4-nitrophenol (or 4-nitrobenzaldehyde) as the nitrogen source. The resulting N-doped P25 TiO2 materials were characterized by UV/Vis and X-ray photoelectron spectroscopies (XPS) that confirmed the presence of nitrogen within the photocatalyst; X-ray diffraction (XRD) techniques confirmed the crystalline phases of the doped material. The photocatalytic activity of N-doped TiO2 was assessed through examining the photodegradation of 4-chlorophenol in aqueous media and iso-propanol as a volatile pollutant under UV/Vis and visible-light irradiation. Under visible light irradiation, undoped P25 was inactive contrary to N-doped P25 that successfully degraded 95% of the 4-chlorophenol (after 10 h) and 23% of iso-propanol (after 2.5 h).

  18. Interaction, at Ambient Temperature and 80 °C, between Minerals and Artificial Seawaters Resembling the Present Ocean Composition and that of 4.0 Billion Years Ago

    Science.gov (United States)

    Carneiro, Cristine E. A.; Stabile, Antonio C.; Gomes, Frederico P.; da Costa, Antonio C. S.; Zaia, Cássia T. B. V.; Zaia, Dimas A. M.

    2016-10-01

    Probably one of the most important roles played by minerals in the origin of life on Earth was to pre-concentrate biomolecules from the prebiotic seas. There are other ways to pre concentrate biomolecules such as wetting/drying cycles and freezing/sublimation. However, adsorption is most important. If the pre-concentration did not occur—because of degradation of the minerals—other roles played by them such as protection against degradation, formation of polymers, or even as primitive cell walls would be seriously compromised. We studied the interaction of two artificial seawaters with kaolinite, bentonite, montmorillonite, goethite, ferrihydrite and quartz. One seawater has a major cation and anion composition similar to that of the oceans of the Earth 4.0 billion years ago (ASW 4.0 Ga). In the other, the major cations and anions are an average of the compositions of the seawaters of today (ASWT). When ASWT, which is rich in Na+ and Cl-, interacted with bentonite and montmorrilonite structural collapse occurred on the 001 plane. However, ASW 4.0 Ga, which is rich in Mg2+ and SO4 2-, did not induce this behavior. When ASW 4.0 Ga was reacted with the minerals for 24 h at room temperature and 80 °C, the release of Si and Al to the fluid was below 1 % of the amount in the minerals—meaning that dissolution of the minerals did not occur. In general, minerals adsorbed Mg2+ and K+ from the ASW 4.0 Ga and these cations could be used for the formation of polymers. Also, when the minerals were mixed with ASW 4.0 Ga at 80 °C and ASWT at room temperature or 80 °C it caused the precipitation of CaSO4•2H2O and halite, respectively. Finally, further experiments (adsorption, formation of polymers, protection of molecules against degradation, primitive cell wall formation) performed under the conditions described in this paper will probably be more representative of what happened on the prebiotic Earth.

  19. Multifactorial effects of ambient temperature, precipitation, farm management, and environmental factors determine the level of generic Escherichia coli contamination on preharvested spinach.

    Science.gov (United States)

    Park, Sangshin; Navratil, Sarah; Gregory, Ashley; Bauer, Arin; Srinath, Indumathi; Szonyi, Barbara; Nightingale, Kendra; Anciso, Juan; Jun, Mikyoung; Han, Daikwon; Lawhon, Sara; Ivanek, Renata

    2015-04-01

    A repeated cross-sectional study was conducted to identify farm management, environment, weather, and landscape factors that predict the count of generic Escherichia coli on spinach at the preharvest level. E. coli was enumerated for 955 spinach samples collected on 12 farms in Texas and Colorado between 2010 and 2012. Farm management and environmental characteristics were surveyed using a questionnaire. Weather and landscape data were obtained from National Resources Information databases. A two-part mixed-effect negative binomial hurdle model, consisting of a logistic and zero-truncated negative binomial part with farm and date as random effects, was used to identify factors affecting E. coli counts on spinach. Results indicated that the odds of a contamination event (non-zero versus zero counts) vary by state (odds ratio [OR] = 108.1). Odds of contamination decreased with implementation of hygiene practices (OR = 0.06) and increased with an increasing average precipitation amount (mm) in the past 29 days (OR = 3.5) and the application of manure (OR = 52.2). On contaminated spinach, E. coli counts increased with the average precipitation amount over the past 29 days. The relationship between E. coli count and the average maximum daily temperature over the 9 days prior to sampling followed a quadratic function with the highest bacterial count at around 24°C. These findings indicate that the odds of a contamination event in spinach are determined by farm management, environment, and weather factors. However, once the contamination event has occurred, the count of E. coli on spinach is determined by weather only.

  20. Drought increases heat tolerance of leaf respiration in Eucalyptus globulus saplings grown under both ambient and elevated atmospheric [CO2] and temperature

    Science.gov (United States)

    Gauthier, Paul P. G.; Crous, Kristine Y.; Ayub, Gohar; Duan, Honglang; Weerasinghe, Lasantha K.; Ellsworth, David S.; Tjoelker, Mark G.; Evans, John R.; Tissue, David T.; Atkin, Owen K.

    2014-01-01

    Climate change is resulting in increasing atmospheric [CO2], rising growth temperature (T), and greater frequency/severity of drought, with each factor having the potential to alter the respiratory metabolism of leaves. Here, the effects of elevated atmospheric [CO2], sustained warming, and drought on leaf dark respiration (R dark), and the short-term T response of R dark were examined in Eucalyptus globulus. Comparisons were made using seedlings grown under different [CO2], T, and drought treatments. Using high resolution T–response curves of R dark measured over the 15–65 °C range, it was found that elevated [CO2], elevated growth T, and drought had little effect on rates of R dark measured at T drought increased R dark at high leaf T typical of heatwave events (35–45 °C), and increased the measuring T at which maximal rates of R dark occurred (T max) by 8 °C (from 52 °C in well-watered plants to 60 °C in drought-treated plants). Leaf starch and soluble sugars decreased under drought and elevated growth T, respectively, but no effect was found under elevated [CO2]. Elevated [CO2] increased the Q 10 of R dark (i.e. proportional rise in R dark per 10 °C) over the 15–35 °C range, while drought increased Q 10 values between 35 °C and 45 °C. Collectively, the study highlights the dynamic nature of the T dependence of R dark in plants experiencing future climate change scenarios, particularly with respect to drought and elevated [CO2]. PMID:25205579

  1. Effect of the slow (K or rapid (k+ feathering gene on body and feather growth and fatness according to ambient temperature in a Leghorn × brown egg type cross

    Directory of Open Access Journals (Sweden)

    Bordas André

    2001-11-01

    Full Text Available Abstract Chicks of both sexes issued from the cross of heterozygous K/k+ cocks for the slow-feathering sex linked K allele with k+ (rapid feathering hens, were compared from the age of 4 to 10 weeks at two ambient temperatures. In individual cages, 30 male chicks of each genotype (K/k+ and k+/k+ were raised at 21°C, and 60 others, distributed in the same way, were raised at 31°C. 71 K/W females and 69 k+/W females were raised in a floor pen at 31°C till 10 weeks of age. In the males, the body weight, feed consumption and feed efficiency at different ages were influenced only by temperature (lower growth rate and feed intake at 31°C; no significant effects of the genotype at locus K nor genotype × temperature interaction were observed. In females, all at 31°C, the genotype (K/W or k+/W had no significant effect on growth rate. Plumage weight and weight of abdominal fat (absolute or related to body weight were measured on half of the males of each group in individual cages, at 10 weeks of age. Moreover, on 36 males and 48 females of the two genotypes, in a group battery at 31°C, the absolute and relative weight of plumage were measured on a sample every two weeks between 4 and 10 weeks. In the first case, no significant effect of genotype appeared. In the second case, an interaction between age and genotype was suggested from plumage weight: its growth, especially in male chicks, appears to be temporarily and unexpectedly faster from 4 to 6 weeks of age for the K/k+ and K/W genotypes.

  2. Commissioning of Two-phase Anaerobic Biological Process for Treatment of Mustard Tuber Production Wastewater at Ambient Temperature%榨菜废水常温两相厌氧生物处理工艺的调试

    Institute of Scientific and Technical Information of China (English)

    许劲; 王阳阳; 田建波; 李森; 李家祥; 余泽强; 蒙丽容

    2013-01-01

    High salinity and difficult start-up are common problems faced by commissioning of twophase anaerobic biological process for treating mustard tuber production wastewater at ambient temperature.The hydrolysis acidification/anaerobic contact oxidation process was applied to wastewater treatment in a mustard tuber production plant in Chongqing.Several approaches,such as controlling the pH of anaerobic unit,domesticating anaerobic salt-tolerant microbes,analyzing biofilm and methanogens in anaerobic contact reactor and adjusting the function of two-phase anaerobic reactor,were investigated to achieve stable operation under low influent COD concentration.The commissioning results showed that the two-phase anaerobic biological process at ambient temperature could be operated stably,and the removal rate of COD was around 75% when pH and volumetric load of the hydrolysis acidification reactor were 6.5 to 7.5 and 1.31 kgCOD/(m3 · d).Those of the anaerobic contact reactor were 6.8 to 7.4 and 0.17kgCOD/(m3 · d) respectively,and the salinity was about 1% (measured by NaCl).%榨菜废水常温两相厌氧处理工艺的调试具有高盐、常温厌氧启动难等不利条件.重庆某榨菜废水处理采用水解酸化/厌氧接触氧化工艺,通过控制厌氧单元的pH值、驯化厌氧耐盐微生物、观察和分析厌氧接触池生物膜与产甲烷菌属、灵活调整两相厌氧反应器功能等方法,探讨了在进水COD浓度偏低的条件下,常温两相厌氧系统达到稳定运行的技术途径.调试结果表明,保持水解酸化池和厌氧接触池的pH值分别为(6.5 ~7.5)和(6.8~7.4)、容积负荷分别为1.31和0.17 kgCOD/(m3·d)、盐度(以NaCl计)为1%左右,可使系统运行稳定,对COD的去除率约为75%.

  3. Pós colheita de bananas-maçã submetidas ao 1-MCP e armazenadas á temperatura ambiente Postharvest of 'apple' banana submetted to 1-MCP and storage in room temperature

    Directory of Open Access Journals (Sweden)

    Ana Carla Marque Pinheiro

    2006-04-01

    Full Text Available Bananas da cultivar Maçã foram adquiridas no estádio dois de coloração da casca (verde maturos e submetidas à ação de 1-MCP. O 1-MCP foi aplicado por 12 horas nas seguintes concentrações: 0 (controle, 50, 100, 150, 200 hL.L-1. Após aplicação, os frutos foram armazenados à temperatura ambiente (temperatura média 20ºC ± 1 e umidade relativa 80% ± 5 e avaliados à medida que atingiam os graus 3, 5 e 7 de coloração da casca. O tratamento com 1-MCP atrasou o início do amadurecimento de bananas-maçã armazenadas sob temperatura ambiente, baseado nas primeiras mudanças de coloração da casca. A aplicação de 1-MCP em bananas-maçã, ditou maiores valores de perda de massa e relação polpa/casca (nos graus 5 e 7 de coloração da casca. O 1-MCP, nas doses 100, 150 e 200 hL.L-1 de 1-MCP promoveu desverdecimento desuniforme e tonalidade avermelhada na casca. O tratamento 50 hL.L-1 de 1-MCP é o mais adequado, por promover a extensão da vida pós-colheita de bananas-maçã da cultivar armazenadas sob temperatura ambiente sem afetar a coloração da casca dos frutos, apresentando qualidade, baseando-se na cor da casca, firmeza, acidez titulável, pH e sólidos solúveis, semelhante ao controle.Mature green 'Apple' bananas were submitted to five concentrations of 1-MCP (0, 50, 100, 150 and 200 hL.L-1 for 12 hours. After treatment, the fruits were stored at room temperature (20ºC ± 1 and 80% ± 5 RH and analyzed at 3,5 and 7 color degree of peel. The treatment with 1-MCP delayed the start of the ripening based in the first changes of peel color. The treatment of 'Apple' bananas with 1-MCP promoted higher values of mass loss and pulp/peel ratio (5 and 7 degrees of color peel. The fruits treated with 100, 150 and 200 nL.L-1 of 1-MCP showed heterogeneous degreening and development of red color on the peel. 1-MCP at 50 nL.L-1 was the most appropriated treatment for promoting the extension of postharvest life of 'Apple' bananas stored

  4. Preparation and performance of desulfurizer CuO/ATP at ambient temperature%CuO/ATP常温脱硫剂的制备及其性能评价

    Institute of Scientific and Technical Information of China (English)

    张智宏; 刘幸幸; 李蒙舟; 梁慧军

    2013-01-01

    用直接沉淀法制备了负载型CuO/ATP常温脱硫剂,用TEM、XRD对CuO/ATP进行了表征,并从扩散及热力学角度分析了焙烧温度、负载量、流速、硫化温度对H2S吸附性能的影响.结果表明,CuO分散在ATP表面,而其分散状态取决于焙烧温度和负载量.焙烧温度过高或负载量过高都将导致CuO的分散性变差,降低气体在脱硫剂中的扩散速率,使得脱硫剂的活性降低.降低流速可使脱硫剂的利用率达到97%,而降低硫化温度至0℃时,脱硫剂性能仍然表现良好,硫容达到了33.17%.%Desulfurizers CuO supported ATP were prepared using direct precipitation method and applied for sorbing H2S at ambient temperature.XRD and TEM were employed to characterize the desulfurizes.The effects of calcination temperature,CuO loading,gas flow rate and reaction temperature on the desulfurization performance were investigated.The diffusion and thermodynamics data demonstrate that dispersion state of CuO on the support depends highly on calcination temperature and CuO loading.Overcalcination or over-loadings may result in serious destructive and different dispersion state of CuO,which cause rapid decline of desulfurizer activity.Low gas flow rates are benefit for sorption capacity and the usage ratios of the sorbents can reach to 97%.When reaction temperature is at 0℃,the desulfurizers still be of high capacity 33.17%.

  5. 常温及常压至1.2GPa条件下异辛烷的拉曼光谱研究%Research on Raman Spectra of Isooctane at Ambient Temperature and Ambient Pressure to 1.2 GPa

    Institute of Scientific and Technical Information of China (English)

    张菲菲; 郑海飞

    2012-01-01

    利用碳化硅压腔在室温(25℃)下,研究了异辛烷(2,2,4-三甲基戊烷)在常压至1.2 GPa条件下的拉曼光谱特征.研究结果表明,异辛烷CH2和CHs的碳氢伸缩振动的拉曼位移随着压力的增大均呈线性向高频方向移动,其拉曼位移与压力的函数关系为:v2873=0.0028P+2873.3;v2905=0.0048P+2905.4;v2935=0.0027P+2935.0;v2960=0.012P+2960.9.在1.0 GPa附近,异辛烷的拉曼位移出现突变,与显微镜下观察发生的异辛烷液-固相变一致.结合异辛烷在常压下的熔点数据,获得了异辛烷的液-固两相相图,并根据克拉贝龙方程获得了液-固相转变过程中的摩尔体积变化量△Vm=4.46×10-6m3·mol-1和熵变△S=-30.32 J.K-1.mol-1.%The experimental study of the Raman spectral character for liquid isooctane(2,2,4-trimethylpentane, ATM) was conducted by moissanite anvil cell at the pressure of 0~l. 2 Gpa and the ambient temperature. The results show that the Raman peaks of the C-H stretching vibration shift to higher frenquencies with increasing pressures. The relations between the system pressure and peaks positions is given as following: v2873=0. 002 8P+2 873. 3; v2905 =0. 004 8P+2 905. 4; V2935 =0. 002 7P+ 2 935. 0; V2 960 =0. 012P+2 960. 9. The Raman spectra of isooctane abruptly changed at the pressure about 1.0 Gpa and the liquid-solid phase transition was observed by microscope. With the freezing pressure at ambient temperature and the melting temperature available at 1 atm, the authors got the liquid-solid phase diagram of isooctane. According to Clapeyron equation, the authors obtained the differences of volume and entropy for the liquid-solid phase transition of isooctane: △Vm =4. 46×10-6 m3 ? Mol-1 and △S=-30. 32 J ? K-1 ? Mol-1.

  6. Experimental study on control logic of lubricant position in direct current inverter compressor under low ambient temperature%低温条件下压缩机油位控制的实验研究

    Institute of Scientific and Technical Information of China (English)

    程德威; 邵丽萍; 沈婵; 姜灿华

    2011-01-01

    It's very important to control the lubricant position in direct current inverter compressor in order to ensure successful start-up and normal running under low ambient temperature. The results of eontrast experiment was showed. It' s favorable to keep lubricant position upon the safe position in starting stage that the oil-return step duration was belonged and oil-return cycle and defrosting cycle were added. It' s also necessary that the pulses must be larger than 350 pls. ,if only one indoor unit need to open in the starting stage.%在低温条件下,为了保证直流变频多练空调的正常启动和运行,压缩机油池内的油位控制是非常重要的.压缩机启动控制对比实验研究结果表明,在启动阶段,延长回油平台时长以及增加回油循环和除霜循环有利于油位保持在安全油位之上.单台室内机开机启动时,相应的电子膨胀阀开度必须在350步以上,才能确保机组正常启动成功及油位安全.

  7. Architectural models of ambient-PRISMA in channel ambient calculus

    OpenAIRE

    Ali, Nour; Tuosto, Emilio

    2011-01-01

    peer-reviewed Ambient-PRISMA is an architectural approach for specifying aspect-oriented software architecture and generating code of distributed and mobile systems. Ambient-PRISMA lacks a precise semantics due to the fact that it is based only on a metamodel. In this paper, Ambient-PRISMA is mapped into a formal language called Channel Ambient Calculus, a process algebra for specifying mobile applications that provides channels and ambients as first-class citizens. We...

  8. Polymeric electrolytes for ambient temperature lithium batteries

    Science.gov (United States)

    Farrington, G. C.

    1987-09-01

    During this reporting period a number of novel solid polymer electrolytes formed by salts of multivalent cations and polyethylene oxide (PEO) have been prepared and characterized. These materials are of interest not only because of their potential ionic conductivities, but also because some of them may have electronic conductivity and oxidizing power which would be useful for novel electrode materials in all-solid-state batteries. Two broad classes of materials were investigated: PEO solutions of Zn(2), Cd(2), and Pb(2), all of which are potential electrolytes for solid-state batteries, and PEO solutions of transition metal salts, which are of interest as possible cathode materials. Mixed compositions containing both divalent cations and lithium ions were also prepared. Electrolytes formed with small, highly-polarizing ions, such as Mg(2) and Ca(2), are essentially pure anion conductors. Electrolytes containing Zn(2) behave similarly, unless they are hydrated, in which case the Zn(2) ions are quite mobile. Electrolytes formed with larger, more polarizable cations, such as Pb(2) and Cd(2), conduct both anions and cations. Solutions of salts of transition metal cations form a third group of electrolytes. Of the electrolytes investigated so far, those formed with Ni(++) salts are the most unusual. It appears as if the transport number of Ni(2) and the electrolyte conductivity can be greatly enhanced by controlling the hydration and dehydration of the polymer.

  9. Studies in Ambient Temperature Ionic Liquids.

    Science.gov (United States)

    1987-06-30

    The polymer films are conductive in the oxidized state and non- conductive when reduced as indicated by the shaoe of cyclic voltammetric curves for...September 2, 1983. OR. A. Osteryoung, "Introduction to Pulse Voltametry ", Tutorial Session on Electrochemistry, Division of Inorganic Chemistry

  10. K2 CO3/AC常温下脱除密闭空间CO2反应机理%Reaction mechanism of dry potassium-based solid sorbent for CO2 capture in confined spaces at ambient temperature

    Institute of Scientific and Technical Information of China (English)

    郭亚飞; 赵传文; 黎昌海; 陆守香

    2014-01-01

    TheremovalofCO2fromconfinedspacestomaintainitsconcentrationatanacceptable level is emerging as a significant task in environmental control and life support system. It is crucial to develop a renewable sorbent with high activity for CO2 capture in confined spaces. A novel potassium-based sorbent of K2 CO3/AC ( AC: activated carbon ) was synthesized via impregnation method. The reaction mechanism and CO2 capture characteristics of the sorbent at ambient temperature were investigated with thermo-gravimetric apparatus ( TGA) . The results showed that weak adsorption capacity of the support of AC on CO2 and H2 O was attributed to the physisorption of its porous structure, while chemisorption was responsible for the CO2 capture process of K2 CO3/AC. It was confirmed that the sorbent exhibited superior capture capacity by converting K2 CO3 into K2 CO3 ·1. 5H2 O in H2 O and KHCO3 in CO2/H2 O with rapid chemical reactions, which were so-called hydration and carbonation. The CO2 capture performance of K2 CO3/AC increased with the increase of CO2 and H2 O concentrations but decreased with the increase of temperature. The results obtained in this study determined the mechanism of K2 CO3/AC for capturing CO2 of low concentration at ambient temperature, which would effectively provide statistical support for CO2 removal from confined spaces.%密闭空间CO2脱除是环境控制和生命保障系统的重要任务,研究适用于密闭空间高活性可再生CO2清除剂至关重要。本文利用热重分析系统对钾基负载型吸收剂K2 CO3/AC ( AC为活性炭)进行实验。在20℃,1%CO2和2%H2 O基准工况下,对比吸收剂和载体AC的反应特性,探索K2 CO3/AC常温下脱除密闭空间CO2反应机理,并探究温度、CO2浓度和H2 O浓度等反应条件对脱碳特性影响。结果表明:载体AC对H2 O和CO2脱除机制为物理吸附作用;K2 CO3/AC主要依靠活性组分K2 CO3与二者的化学反应,在H2 O气氛中通过水

  11. Ambient temperature‐directed flowering time regulation

    NARCIS (Netherlands)

    Verhage, Dina Sara Leonie

    2017-01-01

    As a consequence of a sessile lifestyle, plants are constantly facing a fluctuating environment. In order to both profit maximally and protect themselves from these environmental cues, plants evolved ways to sense and respond to signals. Ambient temperature is one of the cues for which plants have a

  12. Ambient oxygen promotes tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Ho Joong Sung

    Full Text Available Oxygen serves as an essential factor for oxidative stress, and it has been shown to be a mutagen in bacteria. While it is well established that ambient oxygen can also cause genomic instability in cultured mammalian cells, its effect on de novo tumorigenesis at the organismal level is unclear. Herein, by decreasing ambient oxygen exposure, we report a ∼50% increase in the median tumor-free survival time of p53-/- mice. In the thymus, reducing oxygen exposure decreased the levels of oxidative DNA damage and RAG recombinase, both of which are known to promote lymphomagenesis in p53-/- mice. Oxygen is further shown to be associated with genomic instability in two additional cancer models involving the APC tumor suppressor gene and chemical carcinogenesis. Together, these observations represent the first report directly testing the effect of ambient oxygen on de novo tumorigenesis and provide important physiologic evidence demonstrating its critical role in increasing genomic instability in vivo.

  13. Thermal explosion in oscillating ambient conditions

    Science.gov (United States)

    Novozhilov, Vasily

    2016-07-01

    Thermal explosion problem for a medium with oscillating ambient temperature at its boundaries is considered. This is a new problem in thermal explosion theory, not previously considered in a distributed system formulation, but important for combustion and fire science. It describes autoignition of wide range of fires (such as but not limited to piles of biosolids and other organic matter; storages of munitions, explosives, propellants) subjected to temperature variations, such as seasonal or day/night variation. The problem is considered in formulation adopted in classical studies of thermal explosion. Critical conditions are determined by frequency and amplitude of ambient temperature oscillations, as well as by a number of other parameters. Effects of all the parameters on critical conditions are quantified. Results are presented for the case of planar symmetry. Development of thermal explosion in time is also considered, and a new type of unsteady thermal explosion development is discovered where thermal runaway occurs after several periods of temperature oscillations within the medium.

  14. Liquid Water Structure from Anomalous Density under Ambient Condition

    Institute of Scientific and Technical Information of China (English)

    SUN Qiang; ZHENG Hai-Fei

    2006-01-01

    @@ From discussion of the structure of liquid water, we deduce that water under ambient condition is mainly composed of ice Ih-like molecular clusters and clathrate-like molecular clusters. The water molecular clusters remain in a state of chemical equilibrium (reversible clustering reactions). This structural model can be demonstrated by quantitative study on anomalous density with increasing temperature at ambient pressure.

  15. Crisis ambiental y cristianismo

    OpenAIRE

    Felipe Cárdenas

    2008-01-01

    En el artículo se identifican y reconocen algunas opciones que se pueden desarrollar en el cristianismo en relación con la problemática ambiental. Se aborda el dilema bíblico suscitado por interpretaciones antiecológicas y ecológicas. Con base en una lectura de la Biblia, de testimonios cristianos, y en una rememoria de estructuras institucionales, como la parroquia, se analiza el valor que tiene el mensaje cristiano en lo referido a la mitigación de la crisis ambiental.This article identifie...

  16. 不同药物配方对公猪精液常温保存效果研究%Effect of Storage in Ambient Temperature of Boar Semen Using Different Drug Formula

    Institute of Scientific and Technical Information of China (English)

    陈玉霞; 孙克宁; 林峰; 杨婷; 高汉婷; 高腾云

    2011-01-01

    为提高猪精液的保存效果,为猪精液常温保存技术及稀释液配方的研究提供参考依据,设计了3种常温保存希释液配方,并对保存后的精子进行了顶体染色.结果表明:当精子活率为50%与30%时,配方Ⅱ的精子保存时间均显著高于配方Ⅰ与配方Ⅲ(P<0.05),且配方Ⅱ所保存精子的总存活时间也显著高于配方Ⅰ与配方Ⅲ(P<0.05).上述结果表明,配方Ⅱ对猪精液的常温保存效果要优于配方Ⅰ与配方Ⅲ.%In order to improve the storage effect of boar semen, three diluent formulas in ambient temperature was designed to preserve the boar semen, and the acrosome of the sperms was stained after they were preserved. The results showed that the storage time of the sperms stored by formula II was obviously different(P>0.05)from that of formula I and formula Ⅲ when the sperm motility rate was 50% and 30% . The overall survival time of the sperms stored by formula II was also obviously different (P< 0. 05) from that of formula I and formula Ⅲ.

  17. Ambient mass spectrometry imaging

    DEFF Research Database (Denmark)

    Janfelt, Christian; Nørgaard, Asger W

    2012-01-01

    Easy ambient sonic spray ionization (EASI) and desorption electrospray ionization (DESI) were used for imaging of a number of samples, including sections of rat brain and imprints of plant material on porous Teflon. A novel approach termed Displaced Dual-mode Imaging was utilized for the direct...

  18. La radioactividad ambiental

    OpenAIRE

    Rafael Núñez-Lagos Roglá

    2011-01-01

    Se explican los conceptos fundamentales relacionados con la radiactividad y se utilizan para describir la radiactividad ambiental. Se explican también los isótopos de largo periodo y las principales familias radioactivas junto con la radiación cósmica y los radionucleidos cosmogénicos.

  19. La radioactividad ambiental

    Directory of Open Access Journals (Sweden)

    Rafael Núñez-Lagos Roglá

    2011-01-01

    Full Text Available Se explican los conceptos fundamentales relacionados con la radiactividad y se utilizan para describir la radiactividad ambiental. Se explican también los isótopos de largo periodo y las principales familias radioactivas junto con la radiación cósmica y los radionucleidos cosmogénicos.

  20. Ambient Air Quality Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Office of Air and Radiation??s (OAR) Ambient Air Quality Data (Current) contains ambient air pollution data collected by EPA, other federal agencies, as well as...

  1. Ambient Air Quality Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Office of Air and Radiation's (OAR) Ambient Air Quality Data (Current) contains ambient air pollution data collected by EPA, other federal agencies, as well as...

  2. Medio ambiente urbano

    OpenAIRE

    2009-01-01

    El estudio  y análisis  de las interacciones  entre  ambiente  y desarrollo y  su inserción  en los procesos  de  planificación del crecimiento  social y económico  de  los  países  de América Latina, reviste especial interés para proponer alternativas de acción que  conduzcan  al  logro  de  una mejor  calidad de  vida.  El impacto  que las conferencias sobre  el  Medio Ambiente Humano Estocolmo (1972),  Cocoyoc  (1974) o de documentos como "Nuestro Futuro Común" o "Nuestra Propia Agenda" ha...

  3. NIF Ambient Vibration Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Noble, C.R.; Hoehler, M.S., S.C. Sommer

    1999-11-29

    LLNL has an ongoing research and development project that includes developing data acquisition systems with remote wireless communication for monitoring the vibrations of large civil engineering structures. In order to establish the capability of performing remote sensing over an extended period of time, the researchers needed to apply this technology to a real structure. The construction of the National Ignition Facility provided an opportunity to test the data acquisition system on a large structure to monitor whether the facility is remaining within the strict ambient vibration guidelines. This document will briefly discuss the NIF ambient vibration requirements and summarize the vibration measurements performed during the Spring and Summer of 1999. In addition, a brief description of the sensors and the data acquisition systems will be provided in Appendix B.

  4. Utilização das vitaminas C e E em rações para frangos de corte mantidos em ambiente de alta temperatura Use of vitamins C and E on ration for broilers kept in high temperature environment

    Directory of Open Access Journals (Sweden)

    Marcos Gonçalves de Souza

    2011-10-01

    Full Text Available O experimento foi realizado para avaliar os efeitos da suplementação das vitaminas C ou E na ração sobre o desempenho, as características de carcaça e os parâmetros hematológicos de frangos de corte mantidos em ambiente de alta temperatura. Foram utilizados 450 frangos de corte distribuídos em delineamento inteiramente ao acaso, com cinco tratamentos, cada um com nove repetições de 10 aves (período 1 a 21 dias ou de 7 aves (período de 22 a 42 dias por unidade experimental. Os tratamentos foram: ração basal (RB sem suplementação de vitaminas C e E; RB + 300 ppm de vitamina E; RB + 230 ppm de vitamina C; RB + 300 ppm de vitamina E + 230 ppm de vitamina C; e RB + 150 ppm de vitamina E + 115 ppm de vitamina C. Não houve efeito da suplementação das vitaminas C e E no desempenho zootécnico das aves na fase de 1 a 21 dias de idade. Na fase de 1 a 42 dias, a suplementação das vitaminas C e E influenciou somente a conversão alimentar. Os melhores resultados para os pesos absoluto e relativo de peito foram observados nas aves que receberam a ração basal suplementada com as combinações das vitaminas C e E. A concentração plasmática de triiodotironina, a porcentagem de células sanguíneas, a relação heterófilo/linfócito e os pesos absoluto e relativo do baço aos 21 e 42 dias de idade não foram influenciados pela suplementação vitamínica. A suplementação das vitaminas C e ou E não influi no desempenho zootécnico, no peso do baço e nos parâmetros sanguíneos de frangos de corte mantidos até 42 dias de idade em ambiente de alta temperatura. As combinações das vitaminas C e E promovem melhora nos pesos absoluto e relativo de peito de frangos de corte sob alta temperatura.This experiment was carried out to evaluate the effect of supplementation of vitamins C or E in the diet on performance, carcass characteristics and hematological parameters of broilers kept under high environmental temperature. Four hundred and

  5. Generation of sub-part-per-billion gaseous volatile organic compounds at ambient temperature by headspace diffusion of aqueous standards through decoupling between ideal and nonideal Henry's law behavior.

    Science.gov (United States)

    Kim, Yong-Hyun; Kim, Ki-Hyun

    2013-05-21

    In the analysis of volatile organic compounds in air, the preparation of their gaseous standards at low (sub-ppb) concentration levels with high reliability is quite difficult. In this study, a simple dynamic headspace-based approach was evaluated as a means of generating vapor-phase volatile organic compounds from a liquid standard in an impinger at ambient temperature (25 °C). For a given sampling time, volatile organic compound vapor formed in the headspace was swept by bypassing the sweep gas through the impinger and collected four times in quick succession in separate sorbent tubes. In each experiment, a fresh liquid sample was used for each of the four sampling times (5, 10, 20, and 30 min) at a steady flow rate of 50 mL min(-1). The air-water partitioning at the most dynamic (earliest) sweeping stage was established initially in accord with ideal Henry's law, which was then followed by considerably reduced partitioning in a steady-state equilibrium (non-ideal Henry's law). The concentrations of gaseous volatile organic compounds, collected after the steady-state equilibrium, reached fairly constant values: for instance, the mole fraction of toluene measured at a sweeping interval of 10 and 30 min averaged 1.10 and 0.99 nmol mol(-1), respectively (after the initial 10 min sampling). In the second stage of our experiment, the effect of increasing the concentrations of liquid spiking standard was also examined by collecting sweep gas samples from two consecutive 10 min runs. The volatile organic compounds, collected in the first and second 10 min sweep gas samples, exhibited ideal and nonideal Henry's law behavior, respectively. From this observation, we established numerical relationships to predict the mole fraction (or mixing ratio) of each volatile organic compound in steady-state equilibrium in relation to the concentration of standard spiked into the system. This experimental approach can thus be used to produce sub-ppb levels of gaseous volatile organic

  6. Activity of fungal phytases stored in two ways in response to the period of storage at room temperature Atividade de fitases fúngicas armazenadas de duas maneiras em resposta ao período de armazenamento à temperatura ambiente

    Directory of Open Access Journals (Sweden)

    Luciana de Paula Naves

    2012-01-01

    Full Text Available Two distinct experiments were conducted simultaneously with phytases of Aspergillus oryzae and A. niger for determining enzyme activity in response to storage period (up to 180 days at room temperature - RT. In the first experiment, enzymes were stored as they were acquired (pure form and the activity was measured periodically during 180 days of storage at RT. In the second experiment, the phytases were incorporated to a supplement containing vitamins, minerals, and amino acids; and then this supplement was stored at RT up to 180 days, so that every 30 days of storage was collected one aliquot from each replicate for determining enzymatic activity. In conclusion, the phytase activity is affected by storage duration. To ensure 80% of the initial activity, the phytases of A. oryzae and A. niger can be stored in the pure forms for up to 53 and 135 days at RT, respectively. However, if the phytases of A. oryzae and A. niger are incorporated to a supplement containing vitamins, minerals, and amino acids then the storage period at RT should not exceed 67 and 77 days, respectively.Dois experimentos distintos foram realizados simultaneamente com fitases de Aspergillus oryzae e A. niger para a determinação da atividade enzimática em resposta ao período de armazenamento (por até 180 dias em temperatura ambiente - TA. No primeiro experimento, as enzimas foram armazenadas como adquiridas (forma pura e a atividade foi determinada periodicamente durante 180 dias de armazenamento em TA. No segundo experimento, as fitases foram incorporadas a um suplemento contendo vitaminas, minerais e aminoácidos. Então este suplemento foi armazenado em TA por até 180 dias, de modo que, a cada 30 dias de armazenamento, uma alíquota de cada repetição foi coletada para a determinação da atividade enzimática. Conclui-se que a atividade da fitase é afetada pela duração do armazenamento. Para assegurar 80% da atividade inicial, as fitases de A. oryzae e A. niger

  7. 钙基及钠基膨润土涂膜对芒果保鲜效果的研究%Fresh-Keeping Effect of Coating with Calcium Bentonite or Sodium Bentonite on Mango at Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    刘琨; 王雪玲; 陈勇

    2012-01-01

    "Guiqi" mangoes were coated with calcium bentonite or sodium bentonite and stored at ambient temperature(28–33 ℃).Physicochemical and physiological indexes were measured during the storage,including decay index,weight loss rate,respiration intensity,soluble sugar content,titritable acidity,soluble solids,membrane permeability,protopectin and soluble pectin.The results show both calcium bentonite and sodium bentonite could significantly decrease decay index and water loss,restrain the appearance of peak values of respiration intensity,soluble sugar content and soluble solids content,retard the decrease of titritable acidity,slow down the degradation speed of pectin,and maintain cell membrane functionality well.Furthermore,sodium bentonite was more effective in preserving mango than calcium bentonite.%以桂七芒果为试验材料,用钙基及钠基膨润土进行涂膜处理后在室温下(28~33℃)贮藏,对贮藏过程中发病指数、质量损失率、呼吸强度、可溶糖、可滴定酸、可溶性固形物、细胞膜透性、原果胶等物理、化学及生理指标进行测定。结果表明:经涂膜后可以明显降低芒果发病情况和失水率,抑制呼吸强度、可溶糖和可溶性固形物高峰的出现,降低了可滴定酸的下降程度,延缓了果胶的降解速度,较好的保持了细胞膜的功能活性。钠基膨润土涂膜处理的保鲜效果好于钙基膨润土。

  8. 环境温度对架空导线用碳纤维复合芯成型工艺及性能的影响%EFFECT OF AMBIENT TEMPERATURE ON FORMING PROCESS AND PERFORMANCE OF CARBON FIBER REINFORCED COMPOSITE CORE USED FOR OVERHEAD TRANSMISSION LINE

    Institute of Scientific and Technical Information of China (English)

    何州文; 陈新; 药宁娜

    2011-01-01

    The ambient temperature-viscosity relation and the gelation time-temperature relation of two resin system were studied, then the resin system used for pulltrusion molding was confirmed. Carbon fiber reinforced composite core used for overhead transmission line was prepared by using the confirmed resin system, the effects of ambient temperature on forming process and tensile property of carbon fiber reinforced composite core were analyzed and the tensile fracture mechanism of the carbon fiber reinforced composite core was analyzed by SEM. The results showed lhat ambient temperalure had great influence on tensile property and surface per-formance of carbon fiber reinforced composite core. If pulltrusion parameters weren't timely adjusted when ambient temperature changed greatly, the defect of composite core would appeared, such as instance die blocked, whiting, cavity. When ambient temperature was 30℃ , the composite core had highest tensile strength.%研究了两种不同树脂体系黏度与环境温度、凝胶化时间与温度的关系,确定了用于拉挤工艺的树脂体系.采用该树脂体系制备了架空导线用碳纤维复合芯,分析了环境温度对碳纤维复合芯制品成型工艺和拉伸强度的影响,采用扫描电子显微镜分析了碳纤维复合芯的拉伸断裂机理.结果表明,环境温度对碳纤维复合芯的拉伸强度及表现性能影响较大,当环境温度变化较大时如不及时调整成型工艺参数,复合芯制品会出现堵模、白粉、沟痕等缺陷:当环境温度为30C时复合芯制品拉伸强度最高.

  9. Efeito da temperatura ambiente sobre hormônios tireoideanos, temperatura corporal e empenamento de frangos de corte, fêmeas, de diferentes genótipos - DOI: 10.4025/actascianimsci.v27i3.1216 Effect of environmental temperature on tyroid hormones, body temperature and feathering of female broilers of different genotips - DOI: 10.4025/actascianimsci.v27i3.1216

    Directory of Open Access Journals (Sweden)

    Alex Maiorka

    2005-03-01

    Full Text Available Foram criados 360 frangos, fêmeas, Cobb-500 e 360 ISA-Label JA57, em temperaturas termoneutra, quente e fria, utilizando um delineamento inteiramente ao acaso, em modelo fatorial 2 x 3 (2 linhagens e 3 temperaturas com 8 repetições, para avaliar níveis hormonais de tiroxina (T4, triiodotironina (T3, temperatura corporal e empenamento. Alta temperatura ambiente promoveu redução nas concentrações de T3, aos 21, 35 e 42 dias e um aumento de T4 aos 21 dias de idade. Reduziu, também, o empenamento total, empenamento nas regiões do peito, asa e abdômen, promovendo, ainda, aumento na temperatura superficial e corporal das aves. Os frangos, fêmeas, ISA Label tiveram melhor empamento, porém, apresentaram menores temperaturas superficiais, temperatura superficial média e temperatura coporal. Assim, conclui-se que a temperatura ambiente afeta o empenamento de frangas de linhagens de rápido crescimento, que também apresentam menor tolerância ao calor, demonstrada através de uma maior temperatura corporal. A constituição hormonal de T3 e T4 é afetada pela temperatura ambienteThree hundred and sixty female broilers, Cobb – 500 and ISA – Label JA 57 were raised under cold, neutral and hot temperatures in a complete randomized design with 3 x 2 factorial scheme (3 temperatures and 2 strains, with 8 repetitions to evaluate plasmatic levels of Thyroxyne (T4 and Triiodothyronine (T3, body temperature and feathering birds. On hot temperature there was a decrease in T3 levels at 21, 35 and 42 days old and an increase in T4 levels at 21 days old. There was a decrease in the total feathering, in chest, wings and abdomen and an increase in superficial and body temperature. Female broilers ISA Label had better feathering, however lowest superficial temperature, average superficial temperature and body temperature. Environmental temperature affects the feathering of fast growing female broilers, that have low hot tolerance shown through the

  10. Ambient og intelligent teknologi

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh

     Dette notat handler om hvordan humanistisk og samfundsfaglig forskning i øjeblikket nyttiggøres ved udformning af IKT-anvendelser, der er indlejret i vor dagligdag i den forstand, at de indgår som et element i de aktiviteter, vi foretager på arbejdet eller i fritiden. Sådanne anvendelser kaldes ...... undertiden ambiente – noget der omslutter os på alle sider. Rapporten peger også på virkemidler som kan forbedre og øge en humanistisk og samfundsfaglig forskningsindsats....

  11. AOX y medio ambiente.

    OpenAIRE

    1996-01-01

    Los productos organohalogenados son muy utilizados por la industria y su presencia en el medio ambiente está siendo controlada. En los últimos años se han desarrollado varias técnicas de detección, siendo desde finales de los 80 los AOX (adsorbable organic halogens) uno de los parámetros sobre los que se han realizado más estudios. En muchos paises de la Unión Europea y en E.E.U.U. de América, la presencia de compuestos organohalogenados en aguas continentales y suelos está legislada indicand...

  12. Crisis ambiental y cristianismo

    Directory of Open Access Journals (Sweden)

    Felipe Cárdenas

    2008-01-01

    Full Text Available En el artículo se identifican y reconocen algunas opciones que se pueden desarrollar en el cristianismo en relación con la problemática ambiental. Se aborda el dilema bíblico suscitado por interpretaciones antiecológicas y ecológicas. Con base en una lectura de la Biblia, de testimonios cristianos, y en una rememoria de estructuras institucionales, como la parroquia, se analiza el valor que tiene el mensaje cristiano en lo referido a la mitigación de la crisis ambiental.This article identifies and recognizes some options that can be developed in Christianity in relation to the environmental problem. It starts by analyzing the biblical dilemma provoked by both ecological and antiecological interpretations. Based on a reading of the Bible, testimonies from Christians and with a rememory of institutional structures, like the parish, the valué of the Christian message for mitigating the environmental crisis is analyzed.

  13. Effect of KGM Compound Film on Post- harvest Storage of Mango Fruit at Ambient Temperature%魔芋葡甘聚糖复配膜对常温芒果保鲜效果的影响

    Institute of Scientific and Technical Information of China (English)

    李雪晖; 彭述辉; 林好; 余庞熔; 姚敏娜

    2012-01-01

    Fresh fruit of mango variety Haden 1 (Mangifera indicus L. ) were packaged with KGM compound film and polyethylene film with no film as the control, and stored at ambient temperature ( RH = 50%, T = 25 ℃). The mangoes treated were determined during the shelf life in terms of hardness, disease incidence, bad fruit rate, weight loss rate, soluble solid content, respiration rate, Vitamin C content, titratable acid and SOD, PPO and POD activities. Results indicated that the KGM compound film and polyethylene film exhibited the highest respiration peak on the 12th day, 6 days late as against the control, and a higher SOD content at the day 9, 1.75 times higher than the control. The KGM compound film and polyethylene film also significantly reduced mango disease incidences, bad fruit rate and water loss rate, and had higher fruit hardness and Vitamin C content but lower PPO and POD activities in the peel, effectively restraining occurrence of peel browning during mango storage, accumulation of soluble sugar and degradation of titratable acid, and retarding mango ripening. KGM compound film gave a better effect than polyethylene film in improving the mango quality during the shelf life.%利用魔芋葡甘聚糖复配膜、聚乙烯薄膜和无包装等处理,对“海顿1号”芒果进行采后常温(相对湿度为50%,温度为25℃)贮藏保鲜,并对货架期问芒果的硬度、病害、烂果率、失重率、可溶性固形物、呼吸强度、维生素C、可滴定酸和SOD,PPO,POD含量的变化进行了研究。结果表明:经魔芋葡甘聚糖复配膜和聚乙烯薄膜处理的芒果在第12天达到呼吸高峰,呼吸高峰与CK相比推迟了6d,且第9天时,SOD含量为CK的1.75倍。同时,魔芋葡甘聚糖复配膜和聚乙烯薄膜还能减少芒果病害、腐烂率与水分散失,保持较高的果实硬度和VC含量,降低果皮中PPO和POD活性,有效抑制芒果贮藏期间果皮褐变的发生,阻

  14. Efeito de injúrias mecânicas na qualidade de abobrinhas armazenadas em condição ambiente Effect of mechanical injuries on the quality of squash stored at room temperature

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Berlingieri Durigan

    2007-06-01

    Full Text Available Foram avaliados os efeitos de diferentes injúrias mecânicas na qualidade de abobrinhas verdes cv. caipira, em três tipos de lesões: por impacto, compressão e corte. No impacto os frutos foram soltos em queda livre de uma altura de 1,60 m duas vezes (uma batida de cada lado do fruto, a compressão foi feito pela pressão de um peso de 58,8 N por 1 hora e o corte (6 cm de comprimento e 2 mm de profundidade, em triplicata em 2 lados dos frutos efetuado com uma faca apropriada. Após esses tratamentos, os frutos injuriados e os do controle (intactos foram armazenados em condições de ambiente (25°C, 65% UR. As avaliações foram feitas a cada 3 dias, determinando-se atividade respiratória, aparência, perda de massa, pH, teores de sólidos solúveis, acidez titulável, ácido ascórbico, amido e carboidratos solúveis. Durante o período de armazenamento, de 15 dias, as lesões mostraram-se prejudiciais à qualidade, afetando distintamente os parâmetros químicos, a aparência, e diminuindo os dias de possível comercialização dos frutos, em especial naqueles submetidos ao corte e ao impacto. Estas injúrias também ocasionaram maior atividade respiratória dos frutos. A perda de massa fresca foi agravada quando os frutos foram submetidos ao corte. A injúria por impacto e por corte foram as mais prejudiciais para a qualidade das abobrinhas 'Caipira'.The effects of different mechanical injuries were evaluated on green squash cv. Caipira, such as impact, compression and cut. The impact injury was done by dropping the fruit from a height of 1.60 m on a hard and plain surface. Compression was made by pressing a weight of 58.8 N on the squash fruit for 1 hour and the cut was done by using a knife to make wounds (2 mm deep and 6 cm length three times in both sides of the fruits. Injuried and intact fruits were stored at room temperature (25ºC, 65% RH. Evaluations were done every three days, measuring the respiratory activity, appearance, loss

  15. Types for BioAmbients

    Directory of Open Access Journals (Sweden)

    Sara Capecchi

    2010-02-01

    Full Text Available The BioAmbients calculus is a process algebra suitable for representing compartmentalization, molecular localization and movements between compartments. In this paper we enrich this calculus with a static type system classifying each ambient with group types specifying the kind of compartments in which the ambient can stay. The type system ensures that, in a well-typed process, ambients cannot be nested in a way that violates the type hierarchy. Exploiting the information given by the group types, we also extend the operational semantics of BioAmbients with rules signalling errors that may derive from undesired ambients' moves (i.e. merging incompatible tissues. Thus, the signal of errors can help the modeller to detect and locate unwanted situations that may arise in a biological system, and give practical hints on how to avoid the undesired behaviour.

  16. Types for BioAmbients

    CERN Document Server

    Capecchi, Sara; 10.4204/EPTCS.19.7

    2010-01-01

    The BioAmbients calculus is a process algebra suitable for representing compartmentalization, molecular localization and movements between compartments. In this paper we enrich this calculus with a static type system classifying each ambient with group types specifying the kind of compartments in which the ambient can stay. The type system ensures that, in a well-typed process, ambients cannot be nested in a way that violates the type hierarchy. Exploiting the information given by the group types, we also extend the operational semantics of BioAmbients with rules signalling errors that may derive from undesired ambients' moves (i.e. merging incompatible tissues). Thus, the signal of errors can help the modeller to detect and locate unwanted situations that may arise in a biological system, and give practical hints on how to avoid the undesired behaviour.

  17. Reforma constitucional y ambiente

    Directory of Open Access Journals (Sweden)

    Teodoro Bustamante

    2013-09-01

    Full Text Available América Latina está atravesada por una ola de reformas constitucionales. Sus causas, las expectativas que ellas despiertan, los riesgos que se han asociado al proceso de lucha política en su entorno, son temas de un análisis fundamentalmente político; pero hay algunos aspectos en los cuales ese debate tiene una directa repercusión sobre el tema ambiental. En el caso del Ecuador, esto se refleja en el hecho de que una de las innovaciones que se proponen, se refieren a una nueva forma de abordar los temas ambientales, básicamente se establecen Derechos de la Naturaleza.

  18. 不同环境温度下铝球弹丸高速撞击编织物防护屏试验研究%Experimental Investigation of Woven Bumper Shield Impacted by a High-velocity Aluminum Sphere at Different Ambient Temperature

    Institute of Scientific and Technical Information of China (English)

    管公顺; 蒲东东; 哈跃; 庞宝君

    2015-01-01

    利用二级轻气炮发射2017铝球弹丸,在两种环境温度下高速撞击编织物单防护屏结构和填充式结构,研究环境温度对铝网、玄武岩纤维布、Kevlar纤维布防护结构高速撞击损伤与防护特性的影响。用于模拟空间碎片的铝球弹丸直径为3.97 mm,撞击速度为1.47~4.47 km/s,撞击角度为0°,环境温度分别为293 K和393 K。结果表明:当撞击条件相同时,在较高环境温度中,单防护屏结构的编织物防护屏及填充式结构的编织物填充层的撞击穿孔尺寸均增大,三种编织物单防护屏结构的高速撞击防护能力下降,铝网及玄武岩纤维布填充式结构的高速撞击防护性能降低,Kevlar纤维布填充式结构的高速撞击防护性能提高。%A two-stage light gas gun is used to launch 2017-T4 Al-sphere projectiles impacting on single-wall bumper shield and stuffed bumper shield of woven at two kinds of ambient temperature. The effect of ambient temperature on damage and protection characteristic of Al-mesh, Basalt fiber cloth and Kevlar fiber cloth bumpers are studied. The diameter of projectile used to simulate space debris is 3.97 mm. Impact velocities of Al-spheres are varied between 1.47 km/s and 4.47 km/s. The impact angle is 0°. Ambient temperatures are 293 K and 393 K respectively. The results indicated that perforation size of woven bumper of single-wall bumper shield and woven stuffed wall of stuffed bumper shield increased at higher ambient temperature for the same impact condition. At the same time, the protection performance of all single-wall bumper shields of three woven bumpers degraded along with the rising of the ambient temperature, the protection performance of Al-mesh, Basalt fiber cloth stuffed bumper shields degraded and the protection performance of Kevlar fiber cloth stuffed bumper shield enhanced at higher ambient temperature.

  19. CCN activation of ambient and "synthetic ambient" urban aerosol

    Science.gov (United States)

    Burkart, Julia; Reischl, Georg; Steiner, Gerhard; Bauer, Heidi; Leder, Klaus; Kistler, Magda; Puxbaum, Hans; Hitzenberger, R.

    2013-05-01

    In this study, the Cloud Condensation Nuclei (CCN) activation properties of the urban aerosol in Vienna, Austria, were investigated in a long term (11 month) field study. Filter samples of the aerosol below 100 nm were taken in parallel to these measurements, and later used to generate "synthetic ambient" aerosols. Activation parameters of this "synthetic ambient" aerosol were also obtained. Hygroscopicity parameters κ [1] were calculated both for the urban and the "synthetic ambient" aerosol and also from the chemical composition. Average κ for the "synthetic ambient" aerosol ranged from 0.20 to 0.30 with an average value of 0.24, while the κ from the chemical composition of this "synthetic ambient" aerosol was significantly higher (average 0.43). The full results of the study are given elsewhere [2,3].

  20. Effects of Ambient Pressure on Bubble Characteristics

    Institute of Scientific and Technical Information of China (English)

    卢新培; 刘明海; 江中和; 潘垣

    2002-01-01

    The effects of the ambient pressure Pambient on the bubble characteristics of pulsed discharge in water are investigated. The simulation results show that, when Pambient increases from 1 atm to 100 atm, the bubble radius R decreases from 4cma to 7mm, and its pulsation period decreases frown 8ms to 0.2ms. The results also show that the peak pressure of the first shock wave is independent of Pambient, but the peak pressure of the second shock wave caused by the bubble re-expansion decreases when Pambient increases. On the other hand, the larger the ambient pressure, the larger the peak pressure of the plasma in the bubble, while the plasma temperature is independent of Pambient.

  1. Foro Ambiental : CEDENMA, Asamblea Constituyente

    Directory of Open Access Journals (Sweden)

    Anne-Lise Naizot

    2013-09-01

    Full Text Available Resumen de la Mesa redonda: Orientaciones de la nueva Constitución ecuatoriana en materia ambiental: ¿avances o retrocesos en relación con el marco político y filosófico ambiental vigente en algunos países de la región?

  2. Ambient Intelligence Application Based on Environmental Measurements Performed with an Assistant Mobile Robot

    Directory of Open Access Journals (Sweden)

    Dani Martinez

    2014-03-01

    Full Text Available This paper proposes the use of an autonomous assistant mobile robot in order to monitor the environmental conditions of a large indoor area and develop an ambient intelligence application. The mobile robot uses single high performance embedded sensors in order to collect and geo-reference environmental information such as ambient temperature, air velocity and orientation and gas concentration. The data collected with the assistant mobile robot is analyzed in order to detect unusual measurements or discrepancies and develop focused corrective ambient actions. This paper shows an example of the measurements performed in a research facility which have enabled the detection and location of an uncomfortable temperature profile inside an office of the research facility. The ambient intelligent application has been developed by performing some localized ambient measurements that have been analyzed in order to propose some ambient actuations to correct the uncomfortable temperature profile.

  3. 46 CFR 111.01-15 - Temperature ratings.

    Science.gov (United States)

    2010-10-01

    ... type circuit breakers, the ambient temperature for that component is assumed to be 40 °C (104 °F). For installations using Navy type circuit breakers, the ambient temperature for that component is assumed to be...

  4. Does spacecraft potential depend on the ambient electron density?

    Science.gov (United States)

    Lai, S. T.; Martinez-Sanchez, M.; Cahoy, K.; Thomsen, M. F.; Shprits, Y.; Lohmeyer, W. Q.; Wong, F.

    2014-12-01

    In a Maxwellian space plasma model, the onset of spacecraft charging at geosynchronous altitudes is due to the ambient electron, ambient ions, and secondary electrons. By using current balance, one can show that the onset of spacecraft charging depends not on the ambient electron density but instead on the critical temperature of the ambient electrons. If the ambient plasma deviates significantly from equilibrium, a non-Maxwellian electron distribution results. For a kappa distribution, the onset of spacecraft charging remains independent of ambient electron density. However, for double Maxwellian distributions, the densities do have a role in the onset of spacecraft charging. For a dielectric spacecraft in sunlight, the trapping of photoelectrons on the sunlit side enhances the local electron density. Using the coordinated environmental satellite data from the Los Alamos National Laboratory geosynchronous satellites, we have obtained results that confirm that the observed spacecraft potential is independent of the ambient electron density during eclipse and that in sunlight charging the low-energy population around the sunlit side of the spacecraft is enhanced by photoelectrons trapped inside the potential barrier.

  5. Sociología ambiental

    OpenAIRE

    Domínguez Gómez, José Andrés; Aledo Tur, Antonio

    2001-01-01

    Este libro pretende ser un manual para los alumnos de las licenciaturas de sociología, ecología, ciencias ambientales o economía y profesionales de esas ramas que estén interesados en el estudio de las relaciones entre medio ambiente y sociedad desde una aproximación sociológica. El manual está divido en dos partes. La primera desarrolla las principales teorías sociológicas sobre el medio ambiente, así como el heterogéneo pensamiento ambiental. La segunda parte, ofrece capítulos diversos en l...

  6. Ciencia, cultura y medio ambiente

    OpenAIRE

    Ángel Maya, Augusto

    1991-01-01

    La crisis ambiental no es un fenómeno exclusivamente de orden tecnológico. Interroga por igual las organizaciones socio-políticas y los instrumentos científicos para el estudio de la realidad: posiblemente uno de los obstáculos mayores para el encuentro de soluciones adecuadas a la crisis ambiental, radica no en deficiencias de orden técnico, sino en la incapacidad de los instrumentos teóricos para entenderla. La crisis del medio ambiente ha puesto en claro la ambivalencia no sólo de la organ...

  7. La crisis del medio ambiente

    OpenAIRE

    Juan Carlos Quintero Vélez; Clemencia Camacho Delgado

    2013-01-01

    Este artículo, introducción al tema del medio ambiente, pretende proporcionar conceptos básicos para analizar y dimensionar el impacto que genera el hombre sobre los sistemas que soportan la vida. Para entender estos problemas, es indispensable partir de un análisis básico de la relación entre el hombre actual, su medio ambiente, sus necesidades y sus actividades. El autor revisa los antecedentes, las causas y las consecuencias de la crisis ambiental internacional, e intenta dar explicación a...

  8. Efeito da temperatura ambiente sobre o desempenho e características de carcaça de frangos de corte alimentados com dieta controlada e dois níveis de energia metabolizável Effect of environment temperature on performance and carcass characteristics in broilers pair-fed and two levels of metabolizable energy

    Directory of Open Access Journals (Sweden)

    Adhemar Rodrigues de Oliveira Neto

    2000-02-01

    Full Text Available RESUMO - O efeito da temperatura ambiente sobre desempenho e características de carcaça de frangos de corte alimentados com dieta controlada e dois níveis de energia metabolizável foi avaliado. Cento e sessenta frangos de corte machos Hubbard, de 21 dias de idade, com 791+4,12 g de peso médio inicial, foram alojados em ambiente com temperatura termoneutra (23,3±0,58ºC ou quente (32,3±0,31ºC até 42 dias de idade. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 2 x 2 (nível de energia metabolizável [3075 e 3300 kcal de EM/kg] e temperatura ambiente [termoneutro e calor], com cinco repetições e oito aves por unidade experimental. As aves receberam iguais quantidades de ração nos dois ambientes. Ganho de peso e conversão alimentar foram influenciados negativamente pelo calor. Embora os pesos absolutos da carcaça e dos cortes (coxa, sobrecoxa, pernas e peito e o rendimento de peito dos frangos mantidos sob estresse de calor tenham reduzido, o rendimento de carcaça aumentou. Os pesos, absoluto e relativo, das penas foram menores para os animais mantidos no calor. Os pesos, absoluto e relativo, da gordura abdominal foram maiores para os frangos de corte criados no calor. A alta temperatura ambiente reduziu os pesos, absoluto e relativo, de coração, fígado, moela e intestinos, entretanto, o peso relativo dos pulmões e do proventrículo não foi influenciado. O estresse de calor influenciou negativamente o desempenho, reduziu o rendimento de peito e o peso de órgãos vitais, bem como aumentou a gordura abdominal de frangos de corte, independente do nível energético da ração.ABSTRACT - The effect of environmental temperature on performance and carcass characteristics in broilers pair-fed and two levels of metabolizable energy was evaluated. One hundred and sixty Hubbard male broilers, with 21 days of age and 791±4.12 g average initial weight were allotted either under thermoneutral environment (23

  9. Efeitos da restrição alimentar protéica ou energética sobre o crescimento de frangos de corte criados em diferentes temperaturas ambiente Effect of protein or energy restriction on broilers growth reared at different environmental temperatures

    Directory of Open Access Journals (Sweden)

    Elizabete Regina Leone

    2001-06-01

    Full Text Available O presente experimento foi conduzido com o objetivo de avaliar o efeito da restrição protéica ou energética, entre o 8º e o 14º dia de idade, sobre o crescimento e a composição da carcaça de frangos de corte criados em diferentes temperaturas ambientes. Foram utilizados 900 pintos de um dia, machos, da linhagem Ross, os quais foram alojados em três diferentes câmaras climatizadas nas temperaturas de 18, 25 ou 33°C, do 1º ao 42º dia de idade. Para cada temperatura, o delineamento experimental utilizado foi o inteiramente casualizado, em esquema de parcelas subdivididas, em que as parcelas corresponderam ao programa alimentar (controle - 2850 kcal EM/kg e 20% de proteína bruta do 1º ao 21º dia de idade e 3040 kcal EM/kg e 17% de PB do 22º ao 42º dia; restrição energética - 2565 kcal EM/kg e 20% de PB e restrição protéica - 2850 kcal EM/kg e 15% de PB entre o 8º e o 14º dia de idade e as subparcelas, à idade das aves. Entre o 1º e o 7º dia de idade e após o período de restrição as aves receberam a mesma dieta do que os animais controles. Foram avaliados o peso vivo e a composição da carcaça das aves. Os resultados mostraram que, de forma independente da temperatura de criação, as restrições alimentares (energética ou protéica não afetaram o peso vivo e a composição da carcaça aos 42 dias de idade, evidenciando que o frango em temperaturas ambientes diversas mantém a capacidade de ganho compensatório.The present experiment was conducted to evaluate the effect of protein or energy restriction from 8th to 14th days of age, on growth and carcass composition of broiler chickens raised at different environmental temperatures. It was used 900 day-old, male chickens from Ross strain, reared in three environmentally controlled rooms where ambient temperature were maintained at 18, 25 and 33°C up to 42 days of age. For each temperature, a split-plot design was used with feed program as the main plot (control

  10. Association between Ambient Apparent Temperature and Cause-specific Mortality of Ischemic Heart Diseases in Beijing, China%北京市某城区居民缺血性心脏病死亡与大气表观温度之间的相关性研究

    Institute of Scientific and Technical Information of China (English)

    莫运政; 胥美美; 金晓滨; 李国星; 潘小川; 马文军

    2012-01-01

    Objective To explorer the relationship between ambient apparent temperature and ischemic heart disease mortality in one district of Beijing. Methods The data of meteorological factors, air pollutants(SO2, NO2 and PM10) and ischemic heart disease (IHD) mortality in one district of Beijing from 2004 to 2008 were collected and the generalized additive model were fitted with use of natural cubic spline function to adjust trends in time, day of week, air pollutants and other meteorological factors. Results A total of 6 664 IHD death cases were collected, included 3 559(53.41%) male, 3 105(46.59%) female and 4 403 (60.67%) of older people (≥75 years). The graphical associations between ambient apparent temperature and IHD mortality were observed "U" shape. Both decrease at lower temperature and increase at higher temperature of ambient apparent temperature (AAM) can cause more IHD death.Each 1 ℃ decrease in AAM when AAMS12 was associated with an increase in IHD mortality of 1.202%(95%C/:0.123%-2.293%) for all, 0.279%(95%C/:-1.210%-1.790%) for male, 1.807 (95%C/:0.238%-3.401%) for female.Each It decrease in AAM when AAM<12 associated with an increase in IHD mortality of 1.687%(95% CI: 0.623%-2.740%) for all,2.619%(95% CI:1.197%-4.021%) for male, 1.764 (95% C/:0.189%-3.314%) for female.After 24, 48 and 72 h treated, compared with the negative control, the cell survival rates of 64, 128 μg/ml group decreased significantly (P< 0.05), and the DNA Olive tail moment of all groups increased significantly (P<0.05). Compared with the 24 h group, the cell survival rates of all treated groups in 72 h decreased significantly (P<0.05), and the DNA Olive tail moment of all groups in 48 and 72 h increased significantly (P<0.05). Conclusion Stratified analysis shows different associations between ambient apparent temperature and ischemic heart disease mortality.Lower ambient apparent temperature causes stronger adverse effect than higher temperature.Gender causes different effect

  11. Effect of Environmental Temperature During the First Week of Brooding Period on Broiler Chick Body Weight, Viscera and Bone Development Efeito da Temperatura Ambiente Durante a Primeira Semana de Vida de Frangos Sobre o Peso Vivo, Desenvolvimento de Vísceras e Crescimento Ósseo

    Directory of Open Access Journals (Sweden)

    VMB Moraes

    2002-01-01

    Full Text Available The objective of the present study was to assess the development of broiler chicks during the first week post-hatching when reared at three different environmental temperatures. A total of 480 day-old chicks were placed in three environmentally controlled rooms (20, 25 and 35°C from 1 to 7 days of age. Body weight gain, feed and water intake, as well as liver, gizzard, heart, yolk sac and bursa of Fabricius weights were measured daily. Tibia and femur bones were weighed and their length and width (medial diameter were also obtained. The chicks reared at 20º C had lower weight gain and ingested less food than chicks reared at 25°C and less water than chicks kept at 35°C. Relative weights of the liver, heart, and gizzard were affected by environmental temperature, whereas yolk sac and bursa of Fabricius relative weights were not. The data showed that all bone parameters increased with bird age. Environmental temperature did not affect tibia or femur width, however a significant increase in bone weight and length occurred with increasing environmental temperature. These results indicate that brooding temperature of 20°C during the first seven days post-hatching was stressful decreasing broiler bone development and reducing chicks body weight.O presente trabalho teve como objetivo estudar o efeito de diferentes temperaturas-ambiente durante a primeira semana de vida de pintos de corte sob parâmetros zootécnicos, desenvolvimento visceral e crescimento ósseo. Foram utilizados 240 pintos de um dia, alojados em 3 câmaras climáticas, com temperaturas constantes de 20, 25 e 35°C do 1° ao 7° dia de vida. Diariamente, o consumo de água e ração, bem como o peso vivo, o peso relativo do fígado, moela, coração, saco vitelino e bursa de Fabricius foram avaliados. A tíbia e o fêmur também foram pesados e o comprimento e espessura (diâmetro médio mensurados. As aves criadas a 20°C ganharam menos peso e consumiram menos ração do que aves

  12. Ambiente juvenil: discurso ambiental entre jóvenes universitarios.

    OpenAIRE

    Quinn-Anderson, William C.

    2008-01-01

    Esta tesis pretende hacer una aportación al conocimiento del medio ambiente del occidente de México, específicamente de la zona metropolitana de Guadalajara, a partir del estudio de la cultura ambiental manifestada en el discurso de los jóvenes universitarios del ITESO. La apuesta es que puede ser provechoso considerar dentro del concepto de “medio ambiente” no solamente componentes bióticos y abióticos, sino también elementos socioculturales como cultura y significado. Es evidente que hay in...

  13. 环境温度和体内储备物共同影响煤山雀夜间体重的下降%Nocturnal body ass loss in coal tits Periparus ater:the combined effects of ambient temperature and body reserves

    Institute of Scientific and Technical Information of China (English)

    Vicente POLO; Luis M·Crrascal

    2008-01-01

    环境温度和体内储备物水平被认为是鸟类在静止状态下能量利用的重要调节因子(夜间体重降低).然而,以往的研究没有把环境温度和体内储备物对夜间能量维持加以明确的区分.为了研究环境温度是否是为煤山雀(Periparus ater)夜间体重调节的直接因子,在自由取食条件下,实验室控制日-日和日-夜环境温度.温度变化模拟西班牙中部地中海山区秋季日-夜温度的变化.夜间体重取决于黄昏时的体重以及前一天体重的增加值.当前一日白天煤山雀体重增加最大时,记录夜间体重最大降低的比率.然而,环境温度的不可预见性没有影响煤山雀夜间体重降低,可以解释煤山雀内在的生理能量平衡.这些结果提示,当一些环境因子如温度变得不可预见时,鸟类在狭小范围内保持体内储备物%The environmental temperature and the l evel of body reserves have been described as important regulating factors of the amount of energy used at resting (I.e. Nocturnal body mass loss). However, because these variables are associ ated in natural conditions, previous studies have not made a clear distinction between the separate effect of ambient temperature and body reserves on nightly energy management. To investigate whether ambient temperature acts as a proximate factor on nocturnal body mass regulation in captive coal tits Periparus ater, the day-to-day and day-to-night changes in environmental temperatures were experimentally manipulated, under unrestricted food availability. The experiment was conducted within the normal autumn range of temperature variation in a mountain area of continental Mediterranean climate in Central Spain. Nocturnal body mass loss depended on the level of body mass at dusk and daily body-mass gain in the previous day. The largest rates of body mass loss at night were recorded when birds ended the previous day-time period with the highest levels of body reserves obtained

  14. Conhecimento, interdisciplinaridade e Psicologia Ambiental

    Directory of Open Access Journals (Sweden)

    Ombretta Romice

    2005-01-01

    Full Text Available Responde às questões - como os métodos da Psicologia Ambiental devem ser discutidos em um enquadramento interdisciplinar; a Psicologia Ambiental pede alguma abordagem metodológica especial; como a intervenção ambiental é determinada pela interdisciplinaridade; quais são estas disciplinas e como elas se relacionam entre si - baseando-se em experiências profissionais como orientador em um projeto com comunidade, com habitação popular e exclusão social em vários países da Europa, e como consultora. Conclui que as abordagens usadas pelas diferentes profissões são muito separadas, e que apenas metas comuns não são suficientes, sendo também necessários um treino conjunto e identidade de valores.

  15. Validating Firewalls in Mobile Ambients

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis; Hansen, René Rydhof

    1999-01-01

    The ambient calculus is a calculus of computation that allows active processes (mobile ambients) to move between sites. A firewall is said to be protective whenever it denies entry to attackers not possessing the required passwords. We devise a polynomial time algorithm for rejecting proposed...... firewalls that are not guaranteed to be protective. This is based on a control flow analysis for recording what processes may turn up inside what other processes; in particular, we develop a syntax-directed system for specifying the acceptability of an analysis, we prove that all acceptable analyses...

  16. Ambient cosmology and spacetime singularities

    CERN Document Server

    Antoniadis, Ignatios

    2015-01-01

    We present a new approach to the issues of spacetime singularities and cosmic censorship in general relativity. This is based on the idea that standard 4-dimensional spacetime is the conformal infinity of an ambient metric for the 5-dimensional Einstein equations with fluid sources. We then find that the existence of spacetime singularities in four dimensions is constrained by asymptotic properties of the ambient 5-metric, while the non-degeneracy of the latter crucially depends on cosmic censorship holding on the boundary.

  17. Ambient cosmology and spacetime singularities

    Energy Technology Data Exchange (ETDEWEB)

    Antoniadis, Ignatios [Bern University, Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, Bern (Switzerland); Ecole Polytechnique, Palaiseau (France); Cotsakis, Spiros [CERN, Theory Division, Department of Physics, Geneva 23 (Switzerland); National Technical University, School of Applied Mathematics and Physical Sciences, Athens (Greece)

    2015-01-01

    We present a new approach to the issues of spacetime singularities and cosmic censorship in general relativity. This is based on the idea that standard 4-dimensional spacetime is the conformal infinity of an ambient metric for the 5-dimensional Einstein equations with fluid sources. We then find that the existence of spacetime singularities in four dimensions is constrained by asymptotic properties of the ambient 5-metric, while the non-degeneracy of the latter crucially depends on cosmic censorship holding on the boundary. (orig.)

  18. Medio ambiente y responsabilidad social

    OpenAIRE

    2012-01-01

    Las organizaciones, dentro de los procesos de responsabilidad social y con el fin de mejorar la calidad de vida de las comunidades que impactan, han optado por proteger y preservar el medio ambiente de acuerdo a ciertos protocolos y normas internacionales que generan una cultura al respecto. Este cuaderno de investigación aborda la norma ISO 26000, la cual asume el tema de la Responsabilidad Social Empresarial (RSE) en materia de medio ambiente y es una guía para ser implementada en las orga...

  19. Changes in ruminal fermentation and mineral serum level in animals kept in high temperature environments Mudança na fermentação ruminal do alimento e na concentração sérica de minerais em animais mantidos em ambientes de alta temperatura

    Directory of Open Access Journals (Sweden)

    Márcia Saladini Vieira Salles

    2010-04-01

    Full Text Available In order to evaluate the effect of environmental temperature on ruminal fermentation and on mineral levels of growing ruminants, it was used 12 male calves (initial average weight 82.9 ± 7.7 kg, 100 days of age, were employed in a randomized block design (by weight experiment, with repeated weight measurement and two environmental temperatures: thermoneutral (24ºC and heat-stressed (33ºC, during 38 days. The animals exposed to 33ºC presented lower dry matter ingestion, lower T3 (triiodothyronine serum level, higher ammoniacal nitrogen (NH3-N level in the rumen liquid, and higher rectal and body temperatures during all the experimental period when compared to the animals kept in thermoneutral environment (24ºC. The animals kept under heat stress environment (33ºC presented higher calcium serum level, which was the highest on 31st day and the lowest on the 38th day of the experiment; phosphorus level was the lowest during all the experimental period; sodium level was lower on the 17th, 31st and 38th experimental days. Potassium and zinc levels were lower after 24 days; copper level was lower until the 24th day; magnesium level was higher until the 17th day, if compared to the ones from the animals kept in thermoneutral environment (24ºC. The heat-stressed animals presented higher levels of ammoniacal nitrogen in the ruminal liquid and a decrease in the phosphorus, sodium, potassium and zinc serum levels. These results show the necessity of changes on feed management to ruminants in temperatures over the thermal comfort limits so that performance loss is decreased.Para verificar o efeito da temperatura ambiente na fermentação ruminal do alimento e nas concentrações de minerais em bovinos em crescimento, foram utilizados 12 bezerros machos (peso médio inicial de 82,9 ± 7,7 kg com 100 dias de idade, durante 38 dias, em delineamento experimental de blocos ao acaso, com medidas repetidas no tempo e duas temperaturas ambiente: ambiente

  20. Los estudios sobre el ambiente y la ciencia ambiental

    Directory of Open Access Journals (Sweden)

    Amelia Nancy Giannuzzo

    2010-03-01

    Full Text Available La existencia de la ciencia ambiental es reconocida en libros, revistas de publicación científica y carreras de grado y posgrado. Sin embargo, se desconoce su existencia en forma literal o indirecta, al no ser considerado su aporte, por ejemplo, en los planteos referidos sobre la ciencia y la tecnología de la sustentabilidad. En este trabajo se presentan estos antecedentes, relacionándolos con el objetivo del mismo, que es el de aportar a la dilucidación de la existencia y conformación de la ciencia ambiental. Para esto, se analiza la relación de las disciplinas con la dimensión compleja del ambiente como objeto de estudio y aspectos metodológicos derivados. A los fines de aportar al esclarecimiento conceptual, se identifican las distintas acepciones de ambiente comúnmente referidas en la bibliografía. Además, se discuten aspectos relacionados de multidisciplinariedad, interdisciplinariedad y transdisciplinariedad, y sobre el status epistémico de la ciencia ambiental. Se concluye que una mayor precisión conceptual embasada en un marco compartido por las disciplinas que estudian el ambiente, incluida la ciencia ambiental, y los distintos actores involucrados en las problemáticas ambientales, favorecerá el refinamiento de las metodologías tendientes a disminuir la fragmentación de las investigaciones concernientes y las aplicaciones para su resolución.The existence of an environmental science is recognized in books, journals of science as well as in undergraduate and graduate studies. Its existence, however, is unknown either literally or indirectly when, for instance, its contribution to topics connected to the science and technology of sustainability is not considered. This background is presented in this paper and connected to its objective, which is to elucidate the existence and structure of the environmental science. To this goal, I analyse the relationship of the disciplines with the complex dimension of the environment

  1. Gamma radiation effects of Cobalt-60 on tomatoes (Lycopersicon esculentum Mill.) stored at room temperature and under refrigerated conditions; Efeito da radiacao gama do Cobalto-60 em tomates (Lycopersicon esculentum Mill.) armazenados em temperatura ambiente e refrigeracao

    Energy Technology Data Exchange (ETDEWEB)

    Penna, Raquel Medeiros de Almeida

    1994-07-01

    This work was carried out in two distinct experiments. Tomatoes (Lycopersicon esculentum Mill.) of the variety 'Santa Clara in the 'turning' stage (first experiment) and of the variety 'Santa Cruz' in the 'mature-green' stage (second experiment), were irradiated in a Cobalt-60 source with doses of 0.0; 0.5; 1.0; 1.5 e 2.0 kGy, and stored at room temperature (20{+-}2 deg C) and under refrigeration (9 deg C). The aim of the experiments was to verify the effects of the gamma-radiation on the extension of the market life of tomatoes stored under two different temperatures. The following types of analysis were carried out: physical (weight and skin resistance), chemical (brix, pH), sensorial (general appearance, external coloration and firmness) and organoleptic (aroma and flavor), during 30 days of storage, with four evaluations. At the end of the experiment microbiologic and microscopic analyses of histological sections were also performed. In both experiments, occurred a greater loss of weight in the irradiated tomatoes in relation to the controls proportional to the increase in the period of storage, but not to the increase of doses. This effect was more pronounced in fruits stored at room temperature. Concerning the resistance, the fruits of the first experiment showed that irradiation causes softening of the fruit skin. This softening was proportional to the increase of doses, in the 1, 10 e 30th day, and also the fruits irradiated with 1.0, 1.5 and 2.0 kGy showed a higher softening on both temperatures. In the second experiment, on both temperatures, the fruits showed an increase of skin resistance until the 10th day, which diminished until the 30th day. The content of soluble solids was altered by irradiation in the first experiment, and this resulted in a decrease of Brix proportional to the increase of dose. In the second experiment, the radiation induced a maximum Brix value at the 10th day in the fruits maintained under

  2. Empenamento de frangos de corte: efeito da restrição alimentar qualitativa e quantitativa e temperatura ambiente - DOI: 10.4025/actascianimsci.v27i3.1211 Feathering of broiler chickens: effect of feed restriction and room temperature - DOI: 10.4025/actascianimsci.v27i3.1211

    Directory of Open Access Journals (Sweden)

    Alex Maiorka

    2005-03-01

    Full Text Available Estudou-se a restrição alimentar sobre o empenamento de frangos criados em diferentes temperaturas. Para restrição qualitativa, experimento 1, utilizou-se 900 pintainhos, Cobb-500, em delineamento inteiramente ao acaso, em esquema fatorial 3 x 3 (programas alimentares:Controle – 2.950 kcal EM/kg e 22% de PB; Restrição Protéica – 2.950 kcal EM/kg e 17% de PB; Restrição Energética – 2.500 kcal EM/kg e 22% de PB e temperaturas: fria, termoneutra e quente, totalizando 9 tratamentos com 5 repetições. A diminuição de energia e proteína reduziram o empenamento. Na restrição quantitativa, experimento 2, utilizou-se 1.080 pintainhos distribuídos em um delineamento ao acaso em esquema fatorial 3 (níveis de restrição: 0%, 40% e 70% x 3 (temperatura ambiente: fria, termoneutra e quente, totalizando 9 tratamentos com 5 repetições. O empenamento foi prejudicado pela restrição de 70%. O empenamento é sensível à variação protéica e energética da dieta e à temperatura ambienteThe effect of feed restriction on feathering was studied in broilers raised under different temperatures. For qualitative feed restriction trial, experiment 1, 900 Cobb-500 chicks were used in a completely randomized design in 3 x 3 factorial scheme (3 feed programs: Control – 2,950 kcal EM.kg-1 and 22% of CP; Protein Restriction – 2,950 kcal EM.kg-1 and 17% of CP; Energy Restriction – 2,500 kcal EM.kg-1 and 22% of CP; and 3 temperatures: cold, neutral and hot with 9 treatments and 5 repetitions. Energy and Protein restriction reduced feathering. In quantitative restriction, experiment 2, 1080 chicks were distributed in a completely randomized design in 3 x 3 factorial scheme (3 restriction levels: 0%, 40% and 70%; and 3 room temperatures: cold, neutral and hot with 9 treatments and 5 repetitions. Feathering was damaged by 70% of feed restriction. The feathering seems to feel considerably the variations in diet protein and energy and at room

  3. Near-ambient solid polymer fuel cell

    Science.gov (United States)

    Holleck, G. L.

    1993-01-01

    Fuel cells are extremely attractive for extraterrestrial and terrestrial applications because of their high energy conversion efficiency without noise or environmental pollution. Among the various fuel cell systems the advanced polymer electrolyte membrane fuel cells based on sulfonated fluoropolymers (e.g., Nafion) are particularly attractive because they are fairly rugged, solid state, quite conductive, of good chemical and thermal stability and show good oxygen reduction kinetics due to the low specific adsorption of the electrolyte on the platinum catalyst. The objective of this program is to develop a solid polymer fuel cell which can efficiently operate at near ambient temperatures without ancillary components for humidification and/or pressurization of the fuel or oxidant gases. During the Phase 1 effort we fabricated novel integral electrode-membrane structures where the dispersed platinum catalyst is precipitated within the Nafion ionomer. This resulted in electrode-membrane units without interfacial barriers permitting unhindered water diffusion from cathode to anode. The integral electrode-membrane structures were tested as fuel cells operating on H2 and O2 or air at 1 to 2 atm and 10 to 50 C without gas humidification. We demonstrated that cells with completely dry membranes could be self started at room temperature and subsequently operated on dry gas for extended time. Typical room temperature low pressure operation with unoptimized electrodes yielded 100 mA/cm(exp 2) at 0.5V and maximum currents over 300 mA/cm(exp 2) with low platinum loadings. Our results clearly demonstrate that operation of proton exchange membrane fuel cells at ambient conditions is feasible. Optimization of the electrode-membrane structure is necessary to assess the full performance potential but we expect significant gains in weight and volume power density for the system. The reduced complexity will make fuel cells also attractive for smaller and portable power supplies and as

  4. Abstract Interpretation of Mobile Ambients

    DEFF Research Database (Denmark)

    Hansen, René Rydhof; Jensen, J. G.; Nielson, Flemming

    1999-01-01

    We demonstrate that abstract interpretation is useful for analysing calculi of computation such as the ambient calculus (which is based on the p-calculus); more importantly, we show that the entire development can be expressed in a constraint-based formalism that is becoming exceedingly popular...

  5. Nanomaterials vs Ambient Ultrafine Particles

    DEFF Research Database (Denmark)

    Stone, Vicki; Miller, Mark R.; Clift, Martin J. D.

    2016-01-01

    BACKGROUND: A rich literature exists that has demonstrated adverse human health effects following exposure to ambient air particulate matter (PM), with strong support for an important role for ultrafine (nano-sized) particles. At present, relatively little human health or epidemiology data exists...

  6. Shape analysis for mobile ambients

    DEFF Research Database (Denmark)

    Nielson, Hanne Riis; Nielson, Flemming

    2001-01-01

    The ambient calculus is a calculus of computation that allows active processes to move between sites. We present an analysis inspired by state-of-the-art pointer analyses that safely and accurately predicts which processes may turn up at what sites during the execution of a composite system...

  7. Shape analysis for Mobile Ambients

    DEFF Research Database (Denmark)

    Nielson, Hanne Riis; Nielson, Flemming

    2000-01-01

    The ambient calculus is a calculus of computation that allows active processes to move between sites. We present an analysis inspired by state-of-the-art pointer analyses that safety and accurately predicts which processes may turn up at what sites during the execution of a composite system...

  8. Digital identity in ambient environments

    NARCIS (Netherlands)

    Schouten, Ben; Ambekar, Onkar

    2006-01-01

    Embedded systems and ambient technology enable users to interact at any time and anywhere. In the BASIS project for identity management, CWI investigates transparent biometrics in home environments. Possible application areas are user profiling for shopping , listening to one's favourite music and o

  9. La crisis del medio ambiente

    Directory of Open Access Journals (Sweden)

    Juan Carlos Quintero Vélez

    2013-07-01

    Full Text Available Este artículo, introducción al tema del medio ambiente, pretende proporcionar conceptos básicos para analizar y dimensionar el impacto que genera el hombre sobre los sistemas que soportan la vida. Para entender estos problemas, es indispensable partir de un análisis básico de la relación entre el hombre actual, su medio ambiente, sus necesidades y sus actividades. El autor revisa los antecedentes, las causas y las consecuencias de la crisis ambiental internacional, e intenta dar explicación a la problemática nacionalen este campo, y establecer los puntos más críticos en Colombia. Finalmente, con base en los parámetros establecidos por el gobierno, se presenta el concepto de“desarrollo sostenible" como modelo que interrelaciona los procesos económicos, sociales y tecnológicos con el medio ambiente.

  10. Seasonal association between ambient ozone and mortality in Zhengzhou, China

    Science.gov (United States)

    Qin, Lijie; Gu, Jianqin; Liang, Shijie; Fang, Fang; Bai, Weimin; Liu, Xu; Zhao, Tao; Walline, Joseph; Zhang, Shenglong; Cui, Yingjie; Xu, Yaxin; Lin, Hualiang

    2016-12-01

    Different seasonal health effects of ambient ozone (O3) have been reported in previous studies. This might be due to inappropriate adjustment of temperature in different seasons. We used daily data on non-accidental mortality and ambient air pollution in Zhengzhou from January 19, 2013 to June 30, 2015. Season-stratified analyses using generalized additive models were conducted to evaluate the seasonal associations with adjustment of temperature with different lagged days (lag0-1 for warm season, lag0-14 for cold season). We recorded a total of 70,443 non-accidental deaths in Zhengzhou during the study period. Significant associations were observed between ambient O3 and mortality in cold season. Every 10-μg/m3 increment of 24-h O3 of 1-day lagged time was associated with a 1.38% (95% CI 0.60, 2.16%) increase in all cause mortality, 1.35% (95% CI 0.41, 2.30%) increase in cardiovascular mortality, and 1.78% (95% CI 0.43, 3.14%) increase in respiratory mortality. Similar associations were observed when using daily 1- and 8-h maximum concentrations of O3. No significant association was found during warm season. This study suggests a more pronounced ozone-mortality association in cold season in Zhengzhou, and we suggest that different lagged temperatures should be considered when examining the seasonal health effects of ambient ozone.

  11. 不同温度下原油蒸气的爆炸极限和临界氧含量%Explosion limits and critical oxygen content of crude oil vapor at different ambient temperatures

    Institute of Scientific and Technical Information of China (English)

    刘振翼; 李浩; 邢冀; 黄平; 周轶

    2011-01-01

    An explosion accident is possible for process of oil recovery using air injection because of the existence of flammable mixture. So it is necessary to measure the explosion limits and the critical oxygen content of crude oil vapor at different temperatures from 15℃ to 150℃. The measurement result indicated that the explosion limit of crude oil vapor is 4. 62%-14.01% at 15℃ and 4.24%-15.62% at 150℃,while the critical oxygen is 13.15% at 15℃ and 12.47% at 150℃. The range of explosion limit widens and the critical oxygen content decreases with temperature increasing. The correlations between explosion limits as well as critical oxygen content and temperature are founded through numerical analysis, which could be used for forecasting the explosion limits and the critical oxygen content of crude oil at different temperatures.%注空气采油因其过程中存在可燃性混合物,会有发生爆炸事故的可能.通过实验测定了15~150℃之间5个初始温度点原油蒸气的爆炸极限和临界氧含量,15℃时爆炸极限范围为4.62%~14.01%,150℃时爆炸极限范围变宽为4.24%~15.62%,安全氧含量15℃时为13.15%,150℃时降低到12.47%,得出了原油蒸气爆炸极限范围随温度升高而变宽,临界氧含量随温度升高而降低的结论,并运用数值分析原理拟合出原油蒸气爆炸极限和临界氧含量各自随温度变化的规律函数,对预测原油蒸气在其他温度下的爆炸极限和临界氧含量有一定意义.

  12. Thermoluminescence of pure LiF and Lif (TLD-100) irradiated at room temperature; Termoluminiscencia en LiF puro y LiF dosimetrico (TLD-100), irradiados a temperatura ambiente

    Energy Technology Data Exchange (ETDEWEB)

    Sagastibelza Chivite, F.

    1980-07-01

    The thermoluminescence of pure LiF and LiF (TLD-100) crystals irradiated at room temperature with x - or gamma-rays has been studied up to 460 degree centigree. For most of the glow peaks found the kinetics, preexponential factors and activation energies have been determined. These parameters have been obtained by means of the isothermal method. The study of the thermal annealing of the radiation induced F and Z centres has allow to show that there is a correlation among the glow peaks and the annealing stages of these centres. It is concluded that the F and Z - centres play the role of recombination centres for halogen interstitial atom thermally released from traps. Light emission occurs in this recombination. (Author) 120 refs.

  13. Antimicrobial Applications of Ambient--Air Plasmas

    Science.gov (United States)

    Pavlovich, Matthew John

    The emerging field of plasma biotechology studies the applications of the plasma phase of matter to biological systems. "Ambient-condition" plasmas created at or near room temperature and atmospheric pressure are especially promising for biomedical applications because of their convenience, safety to patients, and compatibility with existing medical technology. Plasmas can be created from many different gases; plasma made from air contains a number of reactive oxygen and nitrogen species, or RONS, involved in various biological processes, including immune activity, signaling, and gene expression. Therefore, ambient-condition air plasma is of particular interest for biological applications. To understand and predict the effects of treating biological systems with ambient-air plasma, it is necessary to characterize and measure the chemical species that these plasmas produce. Understanding both gaseous chemistry and the chemistry in plasma-treated aqueous solution is important because many biological systems exist in aqueous media. Existing literature about ambient-air plasma hypothesizes the critical role of reactive oxygen and nitrogen species; a major aim of this dissertation is to better quantify RONS by produced ambient-air plasma and understand how RONS chemistry changes in response to different plasma processing conditions. Measurements imply that both gaseous and aqueous chemistry are highly sensitive to operating conditions. In particular, chemical species in air treated by plasma exist in either a low-power ozone-dominated mode or a high-power nitrogen oxide-dominated mode, with an unstable transition region at intermediate discharge power and treatment time. Ozone (O3) and nitrogen oxides (NO and NO2, or NOx) are mutually exclusive in this system and that the transition region corresponds to the transition from ozone- to nitrogen oxides-mode. Aqueous chemistry agrees well with to air plasma chemistry, and a similar transition in liquid-phase composition

  14. Anual variation of morphologic traits and hair coat surface temperature of Holstein cows in semi-arid environment Variação anual de características morfológicas e da temperatura de superfície do pelame de vacas da raça Holandesa em ambiente semiárido

    Directory of Open Access Journals (Sweden)

    Débora Andréa Evangelista Façanha

    2010-04-01

    Full Text Available This work aimed to study the annual variation of temperature of the coat surface and other traits of coat in Holstein cows managed in a tropical environment by separately considering black coat and white coat. It was measured the coat thickness (mm characteristic, hair length (mm, hair number (hair/cm² and coat surface temperature on 191 crossbred cows with 7/8 and 31/32 Holstein composition distributed in 3 herds in a semi-arid environment. Less dense coats with shorter, flattened hair occurred predominantly in March, a time coinciding to high levels of solar radiation. This type of coat shows low resistance to the flux of latent and sensitive heat through the skin, thus favoring heat loss. The black coat surface temperature was on average 4ºC higher than that of the white one during all the year and its variation followed that of the mean radiant temperature. The models developed to predict the effective thermal conductivity of the coat must take these differences into account because the thermal gradient parallel to the skin surface is not negligible for Holstein cows under the sun in a tropical environment, as well as the other traits.O objetivo neste trabalho foi estudar a variação anual da temperatura superficial e outras características do pelame de vacas holandesas em ambiente tropical, considerando separadamente as malhas negras e brancas. Foram medidas as características espessura da capa (mm, comprimento dos pelos (mm, número de pelos (pelos/cm² e temperatura da superfície do pelame em 191 vacas mestiças com alta proporção de sangue holandês (7/8 e 31/32, respectivamente, distribuídas em três rebanhos em ambiente semiárido. O pelame menos denso, com pelos mais curtos e assentados, que ocorreu predominantemente no mês de março, coincidiu com altos níveis de radiação solar. Esse tipo de pelame apresenta menor resistência ao fluxo de calor latente e sensível através da capa, favorecendo a termólise. A temperatura

  15. Historical Ambient Air Quality Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Historical Ambient Air Quality Data Inventory contains measured and estimated data on ambient air pollution for use in assessing air quality, assisting in...

  16. Interaction, at Ambient Temperature and 80 °C, between Minerals and Artificial Seawaters Resembling the Present Ocean Composition and that of 4.0 Billion Years Ago.

    Science.gov (United States)

    Carneiro, Cristine E A; Stabile, Antonio C; Gomes, Frederico P; da Costa, Antonio C S; Zaia, Cássia T B V; Zaia, Dimas A M

    2016-10-25

    Probably one of the most important roles played by minerals in the origin of life on Earth was to pre-concentrate biomolecules from the prebiotic seas. There are other ways to pre concentrate biomolecules such as wetting/drying cycles and freezing/sublimation. However, adsorption is most important. If the pre-concentration did not occur-because of degradation of the minerals-other roles played by them such as protection against degradation, formation of polymers, or even as primitive cell walls would be seriously compromised. We studied the interaction of two artificial seawaters with kaolinite, bentonite, montmorillonite, goethite, ferrihydrite and quartz. One seawater has a major cation and anion composition similar to that of the oceans of the Earth 4.0 billion years ago (ASW 4.0 Ga). In the other, the major cations and anions are an average of the compositions of the seawaters of today (ASWT). When ASWT, which is rich in Na(+) and Cl(-), interacted with bentonite and montmorrilonite structural collapse occurred on the 001 plane. However, ASW 4.0 Ga, which is rich in Mg(2+) and SO4(2-), did not induce this behavior. When ASW 4.0 Ga was reacted with the minerals for 24 h at room temperature and 80 °C, the release of Si and Al to the fluid was below 1 % of the amount in the minerals-meaning that dissolution of the minerals did not occur. In general, minerals adsorbed Mg(2+) and K(+) from the ASW 4.0 Ga and these cations could be used for the formation of polymers. Also, when the minerals were mixed with ASW 4.0 Ga at 80 °C and ASWT at room temperature or 80 °C it caused the precipitation of CaSO4∙2H2O and halite, respectively. Finally, further experiments (adsorption, formation of polymers, protection of molecules against degradation, primitive cell wall formation) performed under the conditions described in this paper will probably be more representative of what happened on the prebiotic Earth.

  17. GESTIÓN AMBIENTAL METROPOLITANA

    OpenAIRE

    Déctor García, Mtro. Romeo; Correctora de estilo

    2014-01-01

    El artículo aborda la gestión ambiental y metropolitana, a partir de los elementos que han expuesto autores como Raúl Brañes, María del Carmen Carmona Lara, o Martha Schteingart y Clara Eugenia Salazar y otros más que abordan el tema urbano. Se profundiza y detalla con base en la legislación de equilibrio ecológico y protección al ambiente, en la legislación sobre biodiversidad mexiquense como en la atinente a la administración pública local o municipal.Puntos de relieve son las menciones de ...

  18. Tipologia para a contabilidade ambiental

    Directory of Open Access Journals (Sweden)

    Nazlhe Faride Chein Schekaiban

    2007-06-01

    Full Text Available Este artigo revê a visão, as propostas e o desenvolvimento da contabilidade ambiental, refletindo sobre suas implicações, com a finalidade de descobrir e encontrar sua importância e situação. Para se chegar a esse resultado foi preciso realizar uma revisão epistemológica moldada e processo reflexivo de sustentabilidade e da aproximação ao usuário, da percepção da realidade contábil no México e da gerência interna das organizações. As conclusões mostram a contabilidade ambiental no México fora da re-alidade operativa do modelo contábil regional, aumentando a importância de se criar uma cultura capaz de examinar o controle da missão deste tipo de contabilidade.

  19. Ambient Art: Creative Information Representation

    Directory of Open Access Journals (Sweden)

    Russell Beale

    2007-01-01

    Full Text Available Ambient art is the aesthetic presentation of information, using artistic techniques to achieve a pleasing image that also contains hidden depths, where exposure to it over time allows a viewer to understand something about the information sources that it represents. This paper reviews the artistic and computational background of ambient systems, and presents two case studies of systems developed by our research team, from their initial design to the experiences of the people encountering them. The first case presents a photo mosaic of images based on the news headlines coupled with a structured picture based on the weather; the second presents stylistic perspectives on activity in a public space. Both are evaluated and demonstrate that different forms of aesthetically pleasing displays can convey information to viewers.

  20. Structural lubricity under ambient conditions

    Science.gov (United States)

    Cihan, Ebru; Ipek, Semran; Durgun, Engin; Baykara, Mehmet Z.

    2016-06-01

    Despite its fundamental importance, physical mechanisms that govern friction are poorly understood. While a state of ultra-low friction, termed structural lubricity, is expected for any clean, atomically flat interface consisting of two different materials with incommensurate structures, some associated predictions could only be quantitatively confirmed under ultra-high vacuum (UHV) conditions so far. Here, we report structurally lubric sliding under ambient conditions at mesoscopic (~4,000-130,000 nm2) interfaces formed by gold islands on graphite. Ab initio calculations reveal that the gold-graphite interface is expected to remain largely free from contaminant molecules, leading to structurally lubric sliding. The experiments reported here demonstrate the potential for practical lubrication schemes for micro- and nano-electromechanical systems, which would mainly rely on an atomic-scale structural mismatch between the slider and substrate components, via the utilization of material systems featuring clean, atomically flat interfaces under ambient conditions.

  1. Fiscalidad ambiental (curso 2011-2012)

    OpenAIRE

    Gil Maciá, Lorenzo

    2012-01-01

    Tema fiscalidad ambiental. 1. Necesidad económica y jurídica de la protección del medio ambiente. 2. Características, naturaleza y clasificación de los tributos ambientales. 3. Competencias tributarias en el ámbito estatal, autonómico y local. 4. La fiscalidad ambiental en la legislación fiscal española. 5. Perspectivas de futuro en materia de imposición ambiental.

  2. Ambiente psicologico en las organizaciones

    OpenAIRE

    2002-01-01

    El talento humano en las organizaciones se ha convertido en las ultimas decadas en un recurso que se administra de acuerdo al estilo de liderazgo del jefe, lo que implica una marcada relación hacia la tarea, hacia las relaciones con el personal o una combinación de estas dos, que desencadenan en un ambiente psicológico exclusive en cada organización.

  3. Ambiente psicologico en las organizaciones

    Directory of Open Access Journals (Sweden)

    Damarcy Cortés Baracaldo

    2002-01-01

    Full Text Available El talento humano en las organizaciones se ha convertido en las ultimas decadas en un recurso que se administra de acuerdo al estilo de liderazgo del jefe, lo que implica una marcada relación hacia la tarea, hacia las relaciones con el personal o una combinación de estas dos, que desencadenan en un ambiente psicológico exclusive en cada organización.

  4. Calculation of Contactor Action Voltage Value in Different Ambient Temperature%接触器在不同工作环境温度下动作电压值的计算

    Institute of Scientific and Technical Information of China (English)

    周月英

    2011-01-01

    Introduction was made to the method of using serial resistors for calculation when AC contactor was in action performance test under special temperature.Via theory calculation for suck in and release voltage of AC contactor winding,the problem of correctl%介绍了交流接触器动作性能试验时在不同工作环境温度下,使用串联电阻计算的方法。通过对交流接触器线圈吸合和释放电压的理论计算,解决制造企业虽不具备标准要求的环境温度条件而能准确地计算出线圈的吸合和释放电压问题,帮助制造企业合理地控制产品的主要技术数据,提高产品合格率。

  5. Estrategia para la sustentabilidad ambiental

    Directory of Open Access Journals (Sweden)

    Cecilia Erbiti

    2006-01-01

    Full Text Available En el contexto de los postulados conceptuales y metodológicos de la planificación estratégica y de sustentabilidad ambiental, el objetivo de esta investigación es describir el proceso de formulación del Plan de Ordenamiento Territorial del Municipio de Tandil (POTM y analizar su potencialidad para avanzar hacia la sustentabilidad ambiental del sistema. Los resultados de la misma muestran que el POTM no sólo prioriza principios, objetivos y estrategias que materializan las diferentes manifestaciones de la sustentabilidad (económic