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Sample records for chilled ammonia process

  1. Alstom's chilled ammonia CO{sub 2} capture process advances toward commercialization

    SciTech Connect

    Peltier, R.

    2008-02-15

    Carbon dioxide emissions aren't yet regulated by the EPA, but it is likely they will be soon. There are many technically feasible, but as-yet-undemonstrated ways to reduce the considerable carbon footprint of any coal-fired plant, whether it uses conventional or unconventional technology. One promising approach to removing CO{sub 2} from a plant's flue gas uses chilled ammonium bicarbonate to drive the separation process.

  2. Chills

    MedlinePlus

    ... of rest. Evaporation cools the skin and reduces body temperature. Sponging with lukewarm water (about 70°F [21. ... you actually shaking? What has been the highest body temperature connected with the chills? Did the chills happen ...

  3. The Ammonia-Soda Process.

    ERIC Educational Resources Information Center

    Tingle, M.

    1979-01-01

    This article is a condensed version of a commentary written to accompany a set of slides which describes the ammonia-soda process used by the ammonia-soda plant at Northwich of the United Kingdom. (HM)

  4. Chills

    MedlinePlus

    ... fever or an increase in the body's core temperature. Chills are an important symptom with certain diseases ... rest. Evaporation cools the skin and reduces body temperature. Sponging with lukewarm water (about 70°F [21. ...

  5. Chill Down Process of Hydrogen Transport Pipelines

    NASA Technical Reports Server (NTRS)

    Mei, Renwei; Klausner, James

    2006-01-01

    A pseudo-steady model has been developed to predict the chilldown history of pipe wall temperature in the horizontal transport pipeline for cryogenic fluids. A new film boiling heat transfer model is developed by incorporating the stratified flow structure for cryogenic chilldown. A modified nucleate boiling heat transfer correlation for cryogenic chilldown process inside a horizontal pipe is proposed. The efficacy of the correlations is assessed by comparing the model predictions with measured values of wall temperature in several azimuthal positions in a well controlled experiment by Chung et al. (2004). The computed pipe wall temperature histories match well with the measured results. The present model captures important features of thermal interaction between the pipe wall and the cryogenic fluid, provides a simple and robust platform for predicting pipe wall chilldown history in long horizontal pipe at relatively low computational cost, and builds a foundation to incorporate the two-phase hydrodynamic interaction in the chilldown process.

  6. TREATMENT OF AMMONIA PLANT PROCESS CONDENSATE EFFLUENT

    EPA Science Inventory

    The report gives results of an examination of contaminant content and selected treatment techniques for process condensate from seven different ammonia plants. Field tests were performed and data collected on an in-plant steam stripping column with vapor injection into the reform...

  7. Ammonia

    Integrated Risk Information System (IRIS)

    Ammonia ; CASRN 7664 - 41 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effects

  8. Ammonia measurement with a pH electrode in the ammonia/urea-SCR process

    NASA Astrophysics Data System (ADS)

    Kröcher, Oliver; Elsener, Martin

    2007-03-01

    The selective catalytic reduction of nitrogen oxides with ammonia (ammonia SCR) and urea (urea SCR), respectively, is a widespread process to clean flue and diesel exhaust gases due to its simplicity and efficiency. The main challenge of the process is to minimize the ammonia emissions downstream of the SCR catalyst. We found that ammonia emissions of >10 ppm can reliably be detected with a simple pH electrode in the presence of CO2, SOx, NOx, and moderately weak organic acids. 10-20 ppm of ammonia in the exhaust gas are sufficient to neutralize the acids and to increase the pH value from 3 to 6. On this basis a continuous measuring method for ammonia was developed, which was used to control the dosage of urea in the SCR process. While keeping the ammonia emissions after the SCR catalyst at 5-30 ppm an average NOx removal efficiency (DeNOx) of >95% were achieved at a diesel test rig. The method can also be applied for exhaust gases with higher acid contents, if a basic pre-filter is added adsorbing the acidic exhaust components. Compared to water as absorption solution, more precise ammonia measurements are possible, if a 0.1 M NH4Cl absorption solution is applied, whose pH value is changing as a Nernst function of the ammonia concentration.

  9. Chloroplast RNA-Binding Protein RBD1 Promotes Chilling Tolerance through 23S rRNA Processing in Arabidopsis.

    PubMed

    Wang, Shuai; Bai, Ge; Wang, Shu; Yang, Leiyun; Yang, Fen; Wang, Yi; Zhu, Jian-Kang; Hua, Jian

    2016-05-01

    Plants have varying abilities to tolerate chilling (low but not freezing temperatures), and it is largely unknown how plants such as Arabidopsis thaliana achieve chilling tolerance. Here, we describe a genome-wide screen for genes important for chilling tolerance by their putative knockout mutants in Arabidopsis thaliana. Out of 11,000 T-DNA insertion mutant lines representing half of the genome, 54 lines associated with disruption of 49 genes had a drastic chilling sensitive phenotype. Sixteen of these genes encode proteins with chloroplast localization, suggesting a critical role of chloroplast function in chilling tolerance. Study of one of these proteins RBD1 with an RNA binding domain further reveals the importance of chloroplast translation in chilling tolerance. RBD1 is expressed in the green tissues and is localized in the chloroplast nucleoid. It binds directly to 23S rRNA and the binding is stronger under chilling than at normal growth temperatures. The rbd1 mutants are defective in generating mature 23S rRNAs and deficient in chloroplast protein synthesis especially under chilling conditions. Together, our study identifies RBD1 as a regulator of 23S rRNA processing and reveals the importance of chloroplast function especially protein translation in chilling tolerance. PMID:27138552

  10. Chloroplast RNA-Binding Protein RBD1 Promotes Chilling Tolerance through 23S rRNA Processing in Arabidopsis

    PubMed Central

    Yang, Leiyun; Yang, Fen; Wang, Yi; Zhu, Jian-Kang; Hua, Jian

    2016-01-01

    Plants have varying abilities to tolerate chilling (low but not freezing temperatures), and it is largely unknown how plants such as Arabidopsis thaliana achieve chilling tolerance. Here, we describe a genome-wide screen for genes important for chilling tolerance by their putative knockout mutants in Arabidopsis thaliana. Out of 11,000 T-DNA insertion mutant lines representing half of the genome, 54 lines associated with disruption of 49 genes had a drastic chilling sensitive phenotype. Sixteen of these genes encode proteins with chloroplast localization, suggesting a critical role of chloroplast function in chilling tolerance. Study of one of these proteins RBD1 with an RNA binding domain further reveals the importance of chloroplast translation in chilling tolerance. RBD1 is expressed in the green tissues and is localized in the chloroplast nucleoid. It binds directly to 23S rRNA and the binding is stronger under chilling than at normal growth temperatures. The rbd1 mutants are defective in generating mature 23S rRNAs and deficient in chloroplast protein synthesis especially under chilling conditions. Together, our study identifies RBD1 as a regulator of 23S rRNA processing and reveals the importance of chloroplast function especially protein translation in chilling tolerance. PMID:27138552

  11. Localized stem chilling alters carbon processes in the adjacent stem and in source leaves.

    PubMed

    De Schepper, Veerle; Vanhaecke, Lynn; Steppe, Kathy

    2011-11-01

    Transport phloem is no longer associated with impermeable pipes, but is instead considered as a leaky system in which loss and retrieval mechanisms occur. Local stem chilling is often used to study these phenomena. In this study, 5-cm- lengths of stems of 3-year-old oak trees (Quercus robur L.) were locally chilled for 1 week to investigate whether observations at stem and leaf level can be explained by the leakage-retrieval mechanism. The chilling experiment was repeated three times across the growing season. Measurements were made of leaf photosynthesis, carbohydrate concentrations in leaves and bark, stem growth and maximum daily stem shrinkage. Across the growing season, a feedback inhibition in leaf photosynthesis was observed, causing increased dark respiration and starch concentration. This inhibition was attributed to the total phloem resistance which locally increased due to the cold temperatures. It is hypothesized that this higher phloem resistance increased the phloem pressure above the cold block up to the source leaves, inducing feedback inhibition. In addition, an increase in radial stem growth and carbohydrate concentration was observed above the cold block, while the opposite occurred below the block. These observations indicate that net lateral leakage of carbohydrates from the phloem was enhanced above the cold block and that translocation towards regions below the block decreased. This behaviour is probably also attributable to the higher phloem resistance. The chilling effects on radial stem growth and carbohydrate concentration were significant in the middle of the growing season, while they were not at the beginning and near the end of the growing season. Furthermore, maximum daily shrinkages were larger above the cold block during all chilling experiments, indicating an increased resistance in the xylem vessels, also generated by low temperatures. In conclusion, localized stem chilling altered multiple carbon processes in the source leaves

  12. Ammonia Process by Pressure Swing Adsorption

    SciTech Connect

    Dr Felix Jegede

    2010-12-27

    The overall objective of the project is to design, develop and demonstrate a technically feasible and commercially viable system to produce ammonia along with recovery of the products by adsorption separation methods and significantly decrease the energy requirement in ammonia production. This is achieved through a significantly more efficient ammonia psa recovery system. The new ammonia recovery system receives the reactor effluents and achieves complete ammonia recovery, (which completely eliminates the energy intensive refrigeration and condensation system currently used in ammonia production). It also recovers the unused reactants and recycles them back to the reactor, free of potential reactor contaminants, and without the need for re-compression and re-heat of recycle stream thereby further saving more energy. The result is a significantly lower energy consumption, along with capital cost savings.

  13. Streamlined ammonia removal from wastewater using biological deammonification process

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this work we evaluated biological deammonification process to more economically remove ammonia from livestock wastewater. The process combines partial nitritation (PN) and anammox. The anammox is a biologically mediated reaction that oxidizes ammonia (NH4+) and releases di-nitrogen gas (N2) unde...

  14. A lamp thermoelectricity based integrated bake/chill system for advanced photoresist processing

    NASA Astrophysics Data System (ADS)

    Tay, Arthur; Chua, Hui-Tong; Wu, Xiaodong; Wang, Yuheng

    2006-03-01

    The design of an integrated bake/chill module for photoresist processing in microlithography is presented, with emphasis on the spatial and temporal temperature uniformity of the substrate. The system consists of multiple radiant heating zones for heating the substrate, coupled with an array of thermoelectric devices (TEDs) which provide real-time dynamic and spatial control of the substrate temperature. The TEDs also provide active cooling for chilling the substrate to a temperature suitable for subsequent processing steps. The use of lamp for radiative heating also provide fast ramp-up and ramp-down rates during thermal cycling operations. The feasibility of the proposed approach is demonstrate via simulations based on first principle heat transfer modeling. The distributed nature of the design also means that a simple decentralized control scheme can be used to achieve tight spatial and temporal temperature uniformity specifications.

  15. Chilling-induced leaf abscission of Ixora coccinea plants. III. Enhancement by high light via increased oxidative processes.

    PubMed

    Michaeli, Rina; Philosoph-Hadas, Sonia; Riov, Joseph; Shahak, Yosepha; Ratner, Kira; Meir, Shimon

    2001-11-01

    The role of increased oxidation induced by successive stresses of chilling and high light in the induction of leaf abscission was studied in Ixora coccinea plants in relation to auxin metabolism and oxidative processes. Exposure of plants following dark chilling (7 degrees C for 3 days) to high light (500-700 &mgr;mol m-2 s-1 photosynthetically active radiation) for 5 h at 20-25 degrees C enhanced chilling-induced leaf abscission. This abscission was inhibited by pretreatment with the antioxidant butylated hydroxyanisole, alpha-naphthaleneacetic acid or the ethylene action inhibitor, 1-methylcyclopropene. The oxidative processes initiated during the low light period following the dark chilling period, such as indoleacetic acid (IAA) decarboxylation and lipid peroxidation, were further enhanced by subsequent exposure to high light. Photoinhibition, expressed by the reduction of the chlorophyll fluorescence parameter Fv/Fm, was evident following exposure to high light, irrespective of the temperature of the pretreatment, but this reduction persisted only in chilled plants. This suggests that oxidative processes generated during and after the chilling period might have inhibited the recovery from photoinhibition. The chilling stress under darkness induced a 60% reduction in superoxide dismutase (SOD) activity and significant increases (130-600%) in the activities of several other antioxidative enzymes. These data suggest that the chilling-induced reduction in SOD activity may well be responsible for the increase in the oxidative stress induced by the subsequent light treatment, as expressed by the increased enzymatic activities. Taken together, this study provides further support for the involvement of oxidative processes in the events occurring in tissues exposed to sequential chilling and light stresses, leading to reduction in free IAA content in the abscission zone and to leaf abscission. PMID:12060278

  16. Campylobacter and Salmonella in broiler processing – transport through chill

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When market age broilers are transported to processing plants, feces from individual birds in a Campylobacter positive flock can contaminate transport containers (1). Feces, and therefore Campylobacter, is deposited on the floor surface of transport cages. When placed in soiled transport cages pr...

  17. Dewaxing process using agitated heat exchanger to chill solvent-oil and wax slurry to wax filtration temperature

    SciTech Connect

    Broadhurst, Th.E.

    1984-04-10

    In an improved process for dewaxing waxy hydrocarbon oils, wherein said waxy oil is cooled in an indirect chilling zone to a temperature greater than the wax separation temperature whereby wax is precipitated to form a wax-oil-solvent slurry, cooling the slurry to the wax separation temperature in an indirect chilling zone thereby precipitating a further portion of wax from said waxy oil and separating said precipitated wax from the wax-oil-solvent slurry in solid-liquid separation means, the improvement comprises using as the indirect chilling zone an indirect heat exchanger means operated at a high level of agitation. Expressed in terms of Impeller Reynolds Number the agitation is on the order of about 1,000 to 1,000,000. Alternatively, the direct chilling zone is totally replaced by the high agitation indirect heat exchanger means.

  18. Process model for ammonia volatilization from anaerobic swine lagoons incorporating varying wind speeds and biogas bubbling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia volatilization from treatment lagoons varies widely with the total ammonia concentration, pH, temperature, suspended solids, atmospheric ammonia concentration above the water surface, and wind speed. Ammonia emissions were estimated with a process-based mechanistic model integrating ammonia ...

  19. Process monitoring and control: Ammonia measurements in off-gases

    SciTech Connect

    Allendorf, S.; Ottesen, D.; Johnson, H.; Lambert, D.

    1997-05-01

    This interim report describes technical progress in the development of a laser-based, real-time optical monitor for ammonia in off-gas streams from defense waste processing applications at the Savannah River Site (SRS). An optimized monitor has been fabricated by Spectrum Diagnostix using a tunable diode laser operating in the 1.55-{mu}m wavelength region. Instrument detection limits of 2-3 ppm for ammonia are demonstrated that are more than adequate for the SRS required sensitivity of 10 ppm. Laboratory research at Sandia revealed a lack of interference at the operating wavelength by other molecular species that might be present in the SRS off-gas stream. Initial tests of the ammonia monitor by Sandia were conducted at SRS using a bench-scale processing system for surrogate defense waste sludges. The results of these experiments confirmed that ammonia concentrations issuing from the ammonia-scrubber section of the bench-scale reactor were below the design limit of 10 ppm. We also found that no other molecular species in the off-gas produced observable false-positive readings from the monitor. 5 refs., 6 figs.

  20. Modeling and Analysis of Chill and Fill Processes for the EDU Tank

    NASA Technical Reports Server (NTRS)

    Hedayat, A.; Cartagena, W.; Majumdar, A. K.; Leclair, A. C.

    2015-01-01

    NASA's future missions may require long-term storage and transfer of cryogenic propellants. The Engineering Development Unit (EDU), a NASA in-house effort supported by both Marshall Space Flight Center (MSFC) and Glenn Research Center (GRC), is a Cryogenic Fluid Management (CFM) test article that primarily serves as a manufacturing pathfinder and a risk reduction task for a future CFM payload. The EDU test article, comprises a flight like tank, internal components, insulation, and attachment struts. The EDU is designed to perform integrated passive thermal control performance testing with liquid hydrogen in a space-like vacuum environment. A series of tests, with liquid hydrogen as a testing fluid, was conducted at Test Stand 300 at MSFC during summer of 2014. The objective of this effort was to develop a thermal/fluid model for evaluating the thermodynamic behavior of the EDU tank during the chill and fill processes. Generalized Fluid System Simulation Program (GFSSP), an MSFC in-house general-purpose computer program for flow network analysis, was utilized to model and simulate the chill and fill portion of the testing. The model contained the liquid hydrogen supply source, feed system, EDU tank, and vent system. The modeling description and comparison of model predictions with the test data will be presented in the final paper.

  1. The chilling of carcasses.

    PubMed

    Savell, J W; Mueller, S L; Baird, B E

    2005-07-01

    Biochemical processes and structural changes that occur in muscle during the first 24h postmortem play a great role in the ultimate quality and palatability of meat and are influenced by the chilling processes that carcasses are subjected to after slaughter. For beef and lamb, employing chilling parameters that minimize cold shortening is of greatest importance and can be best addressed by ensuring that muscle temperatures are not below 10°C before pH reaches 6.2. For pork, because of the impact of high muscle temperatures and low pH on the development of pale, soft, and exudative (PSE) pork, a more rapid chilling process is needed to reduce PSE with the recommended internal muscle temperature of 10°C at 12h and 2-4°C at 24h. Spray chilling, a system whereby chilled water is applied to carcasses during the early part of postmortem cooling, is used to control carcass shrinkage and to improve chilling rates through evaporative cooling. Delayed chilling can be used to reduce or prevent the negative effects of cold shortening; however, production constraints in high-volume facilities and food safety concerns make this method less useful in commercial settings. Electrical stimulation and alternative carcass suspension programs offer processors the opportunity to negate most or all of the effects of cold shortening while still using traditional chilling systems. Rapid or blast chilling can be an effective method to reduce the incidence of PSE in pork but extreme chilling systems may cause quality problems because of the differential between the cold temperatures on the outside of the carcass compared to the warm muscle temperatures within the carcass (i.e., muscles that are darker in color externally and lighter in color internally). PMID:22063744

  2. Heat-Transfer Measurements in the Primary Cooling Phase of the Direct-Chill Casting Process

    NASA Astrophysics Data System (ADS)

    Caron, Etienne J. F. R.; Baserinia, Amir R.; Ng, Harry; Wells, Mary A.; Weckman, David C.

    2012-10-01

    Thermal modeling of the direct-chill casting process requires accurate knowledge of (1) the different boundary conditions in the primary mold and secondary direct water-spray cooling regimes and (2) their variability with respect to process parameters. In this study, heat transfer in the primary cooling zone was investigated by using temperature measurements made with subsurface thermocouples in the mold as input to an inverse heat conduction algorithm. Laboratory-scale experiments were performed to investigate the primary cooling of AA3003 and AA4045 aluminum alloy ingots cast at speeds ranging between 1.58 and 2.10 mm/s. The average heat flux values were calculated for the steady-state phase of the casting process, and an effective heat-transfer coefficient for the global primary cooling process was derived that included convection at the mold surfaces and conduction through the mold wall. Effective heat-transfer coefficients were evaluated at different points along the mold height and compared with values from a previously derived computational fluid dynamics model of the direct-chill casting process that were based on predictions of the air gap thickness between the mold and ingot. The current experimental results closely matched the values previously predicted by the air gap models. The effective heat-transfer coefficient for primary cooling was also found to increase slightly with the casting speed and was higher near the mold top (up to 824 W/m2·K) where the molten aluminum first comes in contact with the mold than near the bottom (as low as 242 W/m2·K) where an air gap forms between the ingot and mold because of thermal contraction of the ingot. These results are consistent with previous studies.

  3. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT FOR AMMONIA RECOVERY PROCESS

    EPA Science Inventory

    This Technology Verification report describes the nature and scope of an environmental evaluation of ThermoEnergy Corporation’s Ammonia Recovery Process (ARP) system. The information contained in this report represents data that were collected over a 3-month pilot study. The ti...

  4. Determination of heat transfer coefficients at metal/chill interface in the casting solidification process

    NASA Astrophysics Data System (ADS)

    Zhang, Liqiang; Li, Luoxing

    2013-08-01

    The present work focuses on the determination of interfacial heat transfer coefficients (IHTCs) between the casting and metal chill during casting solidification. The proposed method is established based on the least-squares technique and sequential function specification method and can be applied to calculate heat fluxes and IHTCs for other alloys. The accuracy and stability of the method has been investigated by using a typical profile of heat fluxes simulating the practical conditions of casting solidification. In the test process, the effects of various calculation parameters in the inverse algorithm are also analyzed. Moreover, numerically calculated and experimental results are compared by applying the determined IHTCs into the forward heat conduction model with the same boundary conditions. The results show that the numerically calculated temperatures are in good agreement with those measured experimentally. This confirms that the proposed method is a feasible and effective tool for determination of the casting-mold IHTCs.

  5. In situ ammonia analyzer for process control and environmental monitoring

    SciTech Connect

    Monlux, G.; Brand, J.A.; Zmarzly, P.

    1996-12-31

    An ammonia monitor designed for in situ smoke stack or exhaust duct applications is discussed here. A probe composed of a diffusion cell with a protected multipass optical measurement cavity provides the optical interaction with the sample. Other components of the system include signal processing electronics and an embedded PC104 computer platform. This instrument is useful in a wide variety of ammonia monitoring and process control applications, particularly ammonia-based NO{sub x} control technologies, such as selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR). The in situ design eliminates sample handling problems, associated with extractive analysis of ammonia, such as sample line adsorption and heated sample trains and cells. The sensor technology exploited in this instrument is second harmonic spectroscopy using a near infrared diode laser. Data collected during field trials involving both SCR and SNCR applications demonstrate the feasibility and robust operation of this instrument in traditionally problematic operating environments. The instrument can measure other gases by changing the wavelength, either by changing the diode operational set point or by changing the diode. In addition, with straightforward modification the instrument can measure multiple species.

  6. PRETREATMENT AND FRACTIONATION OF CORN STOVER BY AMMONIA RECYCLE PERCOLATION PROCESS. (R831645)

    EPA Science Inventory

    Corn stover was pretreated with aqueous ammonia in a flow-through column reactor,
    a process termed as Ammonia Recycle Percolation (ARP). The aqueous ammonia causes
    swelling and efficient delignification of biomass at high temperatures. The ARP
    process solubilizes abou...

  7. Impact of broiler processing scalding and chilling profiles on carcass and breast meat yield.

    PubMed

    Buhr, R J; Walker, J M; Bourassa, D V; Caudill, A B; Kiepper, B H; Zhuang, H

    2014-06-01

    The effect of scalding and chilling procedures was evaluated on carcass and breast meat weight and yield in broilers. On 4 separate weeks (trials), broilers were subjected to feed withdrawal, weighed, and then stunned and bled in 4 sequential batches (n = 16 broilers/batch, 64 broilers/trial). In addition, breast skin was collected before scalding, after scalding, and after defeathering for proximate analysis. Each batch of 16 carcasses was subjected to either hard (60.0°C for 1.5 min) or soft (52.8°C for 3 min) immersion scalding. Following defeathering and evisceration, 8 carcasses/batch were air-chilled (0.5°C, 120 min, 86% RH) and 8 carcasses/batch were immersion water-chilled (water and ice 0.5°C, 40 min). Carcasses were reweighed individually following evisceration and following chilling. Breast meat was removed from the carcass and weighed within 4 h postmortem. There were significant (P < 0.05) differences among the trials for all weights and yields; however, postfeed withdrawal shackle weight and postscald-defeathered eviscerated weights did not differ between the scalding and chilling treatments. During air-chilling all carcasses lost weight, resulting in postchill carcass yield of 73.0% for soft-scalded and 71.3% for hard-scalded carcasses, a difference of 1.7%. During water-chilling all carcasses gained weight, resulting in heavier postchill carcass weights (2,031 g) than for air-chilled carcasses (1,899 g). Postchill carcass yields were correspondingly higher for water-chilled carcasses, 78.2% for soft-scalded and 76.1% for hard-scalded carcasses, a difference of 2.1%. Only in trials 1 and 4 was breast meat yield significantly lower for hard-scalded, air-chilled carcasses (16.1 and 17.5%) than the other treatments. Proximate analysis of skin sampled after scalding or defeathering did not differ significantly in moisture (P = 0.2530) or lipid (P = 0.6412) content compared with skin sampled before scalding. Skin protein content was significantly

  8. Study on Fabrication of AA4032/AA6069 Cladding Billet Using Direct Chill Casting Process

    NASA Astrophysics Data System (ADS)

    Han, Xing; Zhang, Haitao; Shao, Bo; Li, Lei; Liu, Xuan; Cui, Jianzhong

    2016-04-01

    AA4032/AA6069 cladding billet in size of φ130 mm/φ110 mm was prepared by the modified direct chill casting process, and the parametric effect on casting performance was investigated using numerical simulation. Microstructures, elements distribution, and mechanical properties of the bonding interface were examined. The results show that metallurgical bonding interface can be obtained with the optimal parameters: the casting speed of 130 to 140 mm/min, the internal liquid level height of 50 to 60 mm, and the contact height of 40 to 50 mm. The metallurgical bonding interface is free of any discontinuities due to the fact that the alloying elements diffused across the interface and formed Ni-containing phase. Tensile strength of the cladding billet reaches 225.3 MPa, and the fracture position was located in AA6069 side, suggesting that the interface bonding strength is higher than the strength of AA6069. The interfacial shearing strength is 159.3 MPa, indicating excellent metallurgical bonding.

  9. Photosynthetic responses to chilling in a chilling-tolerant and chilling-sensitive Miscanthus hybrid.

    PubMed

    Friesen, P C; Sage, R F

    2016-07-01

    Miscanthus is a C4 perennial grass being developed for bioenergy production in temperate regions where chilling events are common. To evaluate chilling effects on Miscanthus, we assessed the processes controlling net CO2 assimilation rate (A) in Miscanthus x giganteus (M161) and a chilling-sensitive Miscanthus hybrid (M115) before and after a chilling treatment of 12/5 °C. The temperature response of A and maximum Rubisco activity in vitro were identical below 20 °C in chilled and unchilled M161, demonstrating Rubisco capacity limits or co-limits A at cooler temperatures. By contrast, A in M115 decreased at all measurement temperatures after growth at 12/5 °C. Rubisco activity in vitro declined in proportion to the reduction in A in chilled M115 plants, indicating Rubisco capacity is responsible in part for the decline in A. Pyruvate orthophosphate dikinase activities were also reduced by the chilling treatment when assayed at 28 °C, indicating this enzyme may also contribute to the reduction in A in M115. The maximum extractable activities of PEPCase and NADP-ME remained largely unchanged after chilling. The carboxylation efficiency of the C4 cycle was depressed in both genotypes to a similar extent after chilling. ΦP :ΦCO2 remained unchanged in both genotypes indicating the C3 and C4 cycles decline equivalently upon chilling. PMID:26714623

  10. Process and apparatus for recovery of sulfur from ammonia containing acid gas streams

    SciTech Connect

    Palm, J.W.

    1987-02-17

    This patent describes a Claus process for the recovery of sulfur, the steps comprising: passing a first stream containing hydrogen sulfide, sulfur dioxide, and ammonia through a low temperature Claus catalytic conversion zone and depositing elemental sulfur and ammonium compounds on catalyst therein; deriving a regeneration stream from the Claus process and regenerating the resulting laden catalyst therewith vaporizing sulfur and ammonia therefrom and producing a regeneration effluent stream comprising elemental sulfur and ammonia; cooling the regeneration effluent stream and condensing elemental sulfur therefrom and producing a sulfur lean regeneration effluent stream; introducing at least a portion of the sulfur lean regeneration effluent stream into a hydrogenation zone and converting substantially all sulfur compounds therein to hydrogen sulfide. The resulting hydrogen sulfide containing stream is introduced into an ammonia removal zone. The resulting stream is contacted with a first aqueous stream and produces a second aqueous stream enriched in ammonia and a sulfur lean regeneration effluent stream reduced in ammonia content; removing ammonia from the second aqueous stream and producing an ammonia enriched stream; returning the sulfur lean regeneration effluent stream reduced in ammonia content to the Claus process adjacent and downstream of the point of derivation of the regeneration stream for the further recovery of sulfur therefrom; and introducing the ammonia enriched stream into an ammonia conversion zone and reducing the concentration of ammonia therein.

  11. Chilling rate effects on pork loin tenderness in commercial processing plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present experiment was conducted to provide a large-scale objective comparison of pork LM tenderness and other meat quality traits between packing plants that differ in stunning method and carcass chilling rate. For each of two replicates, hogs were sourced from a single barn of a commercial fi...

  12. Impact of broiler processing scalding and chilling profiles on carcass and breast meat yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of scalding and chilling profiles was evaluated on carcass and breast meat yield in broilers. On 4 separate weeks, 5 to 7 wk old broiler flocks were subjected to a 10 h feed withdrawal, cooped, transported, banded for identification, weighed (live weight), shackled, and then stunned (14...

  13. Impact of broiler processing scalding and chilling profiles on carcass and breast meat yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of scalding and chilling procedures was evaluated on carcass and breast meat yield in broilers. On 4 separate weeks, broilers were subjected to feed withdrawal, weighed, and then stunned and bled in sequential batches (n=16/batch). Breast skin was collected before scalding, after scaldi...

  14. CO/sub 2/ removal from ammonia synthesis gas with SELEXOL Solvent Process

    SciTech Connect

    Shah, V.A.

    1987-01-01

    The high cost of energy which has prevailed since the 70's has forced ammonia producers to seek new methods to save energy and lower the ammonia production cost. The purpose of this paper is to discuss the use of SELEXOL Solvent Process for treatment of ammonia synthesis gas and discuss a patented SELEXOL process scheme which permits substantially 100% carbon dioxide recovery. This paper also describes: the SELEXOL Process Technology; treating of Ammonia Synthesis Gas; philosophy; high CO/sub 2/ Recovery Process; 100% CO2 Recovery Process; cost and Utility Requirement; plant Performance Data.

  15. Chilling tolerant U.S. processing cucumber (Cucumis sativus L.): three advanced backcross and ten inbred backcross lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental stresses such as chilling temperatures can reduce seed germination rate, seeding emergence rate, flower and fruit development, marketable yield, and postharvest fruit storage longevity in cucumber (Cucumis sativus L.). Chilling temperatures occur in unpredictable patterns, making it d...

  16. Improved process model for ammonia volatilization from anaerobic swine lagoons under varying wind speeds and gas bubbling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia volatilization from treatment lagoons varies widely with the lagoon water total ammonia concentration, pH, temperature, suspended solids, atmospheric ammonia concentration above the water surface, and wind speed. Ammonia emissions were estimated with a process-based mechanistic model using a...

  17. Ammonia scrubber testing during IDMS SRAT and SME processing. Revision 1

    SciTech Connect

    Lambert, D.P.

    1995-04-28

    This report summarizes results of the Integrated DWPF (Defense Waste Processing Facility) Melter System (IDMS) ammonia scrubber testing during the PX-7 run (the 7th IDMS run with a Purex type sludge). Operation of the ammonia scrubber during IDMS Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) processing has been completed. The ammonia scrubber was successful in removing ammonia from the vapor stream to achieve NH3 concentrations far below the 10 ppM vapor exist design basis during SRAT processing. However, during SME processing, vapor NH3 concentrations as high as 450 ppM were measured exiting the scrubber. Problems during the SRAT and SME testing were vapor bypassing the scrubber and inefficient scrubbing of the ammonia at the end of the SME cycle (50% removal efficiency; 99.9% is design basis efficiency).

  18. Aerobic and anaerobic microbiology of the immersion chilling procedure during poultry processing.

    PubMed

    Voidarou, C; Vassos, D; Kegos, T; Koutsotoli, A; Tsiotsias, A; Skoufos, J; Tzora, A; Maipa, V; Alexopoulos, A; Bezirtzoglou, E

    2007-06-01

    The development of treatments to reduce bacterial numbers on poultry carcasses is important for the overall hygienic quality of birds. The important washing effect of the immersion chilling procedure is discussed. Systematic monitoring of fecal bacterial indicators as well as some classic pathogens was performed at selected critical points in a water chiller ecosystem. Clostridium perfringens, fecal coliforms, Enterococcus sp., and Streptococcus sp. were found in all water chiller samples. The temperature of the chiller ecosystem varied according to location: Escherichia coli and Salmonella sp. were found at 16 degrees C, compared with the 4 degrees C location, where these species were found in lower numbers. Moreover, the psychrotrophic bacterium Pseudomonas was found only at this last location. The temperature of the water during the immersion chilling procedure was unfavorable for the growth of Campylobacter sp., whose presence was always strictly associated with a pH close to 6. Spore forms of C. perfringens were persistent in all locations and seemed to be a reliable indicator of contamination of the water chiller ecosystem. PMID:17495095

  19. Process for synthesis of ammonia borane for bulk hydrogen storage

    SciTech Connect

    Autrey, S Thomas; Heldebrant, David J; Linehan, John C; Karkamkar, Abhijeet J; Zheng, Feng

    2011-03-01

    The present invention discloses new methods for synthesizing ammonia borane (NH.sub.3BH.sub.3, or AB). Ammonium borohydride (NH.sub.4BH.sub.4) is formed from the reaction of borohydride salts and ammonium salts in liquid ammonia. Ammonium borohydride is decomposed in an ether-based solvent that yields AB at a near quantitative yield. The AB product shows promise as a chemical hydrogen storage material for fuel cell powered applications.

  20. Modeling and analysis of chill and fill processes for the cryogenic storage and transfer engineering development unit tank

    NASA Astrophysics Data System (ADS)

    Hedayat, A.; Cartagena, W.; Majumdar, A. K.; LeClair, A. C.

    2016-03-01

    NASA's future missions may require long-term storage and transfer of cryogenic propellants. The Engineering Development Unit (EDU), a NASA in-house effort supported by both Marshall Space Flight Center (MSFC) and Glenn Research Center, is a cryogenic fluid management (CFM) test article that primarily serves as a manufacturing pathfinder and a risk reduction task for a future CFM payload. The EDU test article comprises a flight-like tank, internal components, insulation, and attachment struts. The EDU is designed to perform integrated passive thermal control performance testing with liquid hydrogen (LH2) in a test-like vacuum environment. A series of tests, with LH2 as a testing fluid, was conducted at Test Stand 300 at MSFC during the summer of 2014. The objective of this effort was to develop a thermal/fluid model for evaluating the thermodynamic behavior of the EDU tank during the chill and fill processes. The Generalized Fluid System Simulation Program, an MSFC in-house general-purpose computer program for flow network analysis, was utilized to model and simulate the chill and fill portion of the testing. The model contained the LH2 supply source, feed system, EDU tank, and vent system. The test setup, modeling description, and comparison of model predictions with the test data are presented.

  1. Chemical Processing of Pure Ammonia and Ammonia-Water Ices Induced by Heavy Ions

    NASA Astrophysics Data System (ADS)

    Bordalo, V.; da Silveira, E. F.; Lv, X. Y.; Domaracka, A.; Rothard, H.; Seperuelo Duarte, E.; Boduch, P.

    2013-09-01

    Cosmic rays are possibly the main agents to prevent the freeze-out of molecules onto grain surfaces in cold dense clouds. Ammonia (NH3) is one of the most abundant molecules present in dust ice mantles, with a concentration of up to 15% relative to water (H2O). FTIR spectroscopy is used to monitor pure NH3 and NH3-H2O ice samples as they are irradiated with Ni and Zn ion beams (500-600 MeV) at GANIL/France. New species, such as hydrazine (N2H4), diazene (N2H2 isomers), molecular hydrogen (H2), and nitrogen (N2) were identified after irradiation of pure NH3 ices. Nitrous oxide (N2O), nitrogen oxide (NO), nitrogen dioxide (NO2), and hydroxylamine (NH2OH) are some of the products of the NH3-H2O ice radiolysis. The spectral band at 6.85 μm was observed after irradiation of both types of ice. Besides the likely contribution of ammonium (NH_{4}^{+}) and amino (NH2) radicals, data suggest a small contribution of NH2OH to this band profile after high fluences of irradiation of NH3-H2O ices. The spectral shift of the NH3 "umbrella" mode (9.3 μm) band is parameterized as a function of NH3/H2O ratio in amorphous ices. Ammonia and water destruction cross-sections are obtained, as well as the rate of NH3-H2O (1:10) ice compaction, measured by the OH dangling bond destruction cross-section. Ammonia destruction is enhanced in the presence of H2O in the ice and a power law relationship between stopping power and NH3 destruction cross-section is verified. Such results may provide relevant information for the evolution of molecular species in dense molecular clouds.

  2. Control of ammonia air pollution through the management of thermal processes in cowsheds.

    PubMed

    Bleizgys, Rolandas; Bagdoniene, Indre

    2016-10-15

    Experimental researches performed in manufacturing cowsheds have demonstrated a variation of ammonia concentration and the factors influencing this most during different periods of the year. The process of ammonia evaporation from manure is influenced by many varying and interrelated factors with temperature and the intensity of air ventilation being the most critical ones. The influence of these factors on the process of ammonia evaporation was established by laboratory researches. An increase in temperature results in an exponential increase in ammonia emission, whereas the dependence of the emission on the air velocity is best expressed by a second degree polynomial. The results obtained may be used as a forecast of the ammonia emissions from cowsheds during different periods of the year. Intensive ventilation is required for the removal of excess moisture from the housing, and this limits the possibilities to reduce ammonia emissions by controlling the intensity of ventilation. A reduction in the amount of ventilation is only recommended if the air quality indices meet the requirements applied to the housing. Better opportunities to reduce ammonia emissions are provided through management of the thermal processes in a cowshed. If the average annual air temperature (11.3°C) is reduced by one degree in a cubicle housing cowshed, the ammonia emissions will decrease by 10%. PMID:27350091

  3. CHEMICAL PROCESSING OF PURE AMMONIA AND AMMONIA-WATER ICES INDUCED BY HEAVY IONS

    SciTech Connect

    Bordalo, V.; Da Silveira, E. F.; Seperuelo Duarte, E.

    2013-09-10

    Cosmic rays are possibly the main agents to prevent the freeze-out of molecules onto grain surfaces in cold dense clouds. Ammonia (NH{sub 3}) is one of the most abundant molecules present in dust ice mantles, with a concentration of up to 15% relative to water (H{sub 2}O). FTIR spectroscopy is used to monitor pure NH{sub 3} and NH{sub 3}-H{sub 2}O ice samples as they are irradiated with Ni and Zn ion beams (500-600 MeV) at GANIL/France. New species, such as hydrazine (N{sub 2}H{sub 4}), diazene (N{sub 2}H{sub 2} isomers), molecular hydrogen (H{sub 2}), and nitrogen (N{sub 2}) were identified after irradiation of pure NH{sub 3} ices. Nitrous oxide (N{sub 2}O), nitrogen oxide (NO), nitrogen dioxide (NO{sub 2}), and hydroxylamine (NH{sub 2}OH) are some of the products of the NH{sub 3}-H{sub 2}O ice radiolysis. The spectral band at 6.85 {mu}m was observed after irradiation of both types of ice. Besides the likely contribution of ammonium (NH{sub 4}{sup +}) and amino (NH{sub 2}) radicals, data suggest a small contribution of NH{sub 2}OH to this band profile after high fluences of irradiation of NH{sub 3}-H{sub 2}O ices. The spectral shift of the NH{sub 3} ''umbrella'' mode (9.3 {mu}m) band is parameterized as a function of NH{sub 3}/H{sub 2}O ratio in amorphous ices. Ammonia and water destruction cross-sections are obtained, as well as the rate of NH{sub 3}-H{sub 2}O (1:10) ice compaction, measured by the OH dangling bond destruction cross-section. Ammonia destruction is enhanced in the presence of H{sub 2}O in the ice and a power law relationship between stopping power and NH{sub 3} destruction cross-section is verified. Such results may provide relevant information for the evolution of molecular species in dense molecular clouds.

  4. Ammonia production from coal by utilization of Texaco coal gasification process

    SciTech Connect

    Watson, J.R.; McClanhan, T.S.; Weatherington, R.W.

    1983-12-01

    Operating data will be presented for the coal gasification and gas purification unit which has been retrofitted to the front end of an existing ammonia plant. The plant uses 200 tons per day of coal and produces 135 tons per day of ammonia. The plant uses the Texaco coal gasification process, Haldor-Topsoe catalyst systems, Selexol acid gas removal process, and the Holmes-Stretford sulfur recovery process.

  5. Carbon Capture by a Continuous, Regenerative Ammonia-Based Scrubbing Process

    SciTech Connect

    Resnik, K.P.; Yeh, J.T.; Pennline, H.W.

    2006-10-01

    Overview: To develop a knowledge/data base to determine whether an ammonia-based scrubbing process is a viable regenerable-capture technique that can simultaneously remove carbon dioxide, sulfur dioxide, nitric oxides, and trace pollutants from flue gas.

  6. Revamping existing ammonia plants with a new low-energy process

    SciTech Connect

    Banquy, D.

    1984-01-01

    In this process, only part of the natural gas feed is treated in the primary reformer, and the rest is reformed directly in the secondary reformer using excess air. The excess nitrogen is removed in a cryogenic separation upstream of the synthesis loop. The features of this new low energy ammonia process, and the related advantages in terms of energy savings, make it suitable for revamping existing ammonia plants, with attractive economics.

  7. Process-scale modelling of microstructure in direct chill casting of aluminium alloys

    NASA Astrophysics Data System (ADS)

    Bedel, M.; Heyvaert, L.; Založnik, M.; Combeau, H.; Daloz, D.; Lesoult, G.

    2015-06-01

    The mechanical properties of an alloy being related to its microstructure, the understanding of the mechanisms responsible for the grain structure formation in direct chill casting is crucial. However, the grain size prediction by modelling is difficult since a variety of multi-scale coupled phenomena have to be considered. Nucleation and growth of the grains are interrelated, and the macroscopic transport phenomena such as the motion of grains and inoculant particles with the flow impact the nucleation-gowth competition. Thus we propose to study the grain size distribution of a 5182 alloy industrial scale slab of 510 mm thickness, both non-inoculated and inoculated with Al-3Ti-1B, for which experimental grain size measurements are available. We use a volume-averaged two-phase multi-scale model that describes nucleation from inoculant particles and grain growth, fully coupled with macroscopic transport phenomena: fluid flow induced by natural convection and solidification shrinkage, heat, mass and solute mass transport, grains and inoculant particles motion. We analyze the effect of liquid and grain motion as the effect of grain morphology on microstructure formation and we show in which extent those phenomena are responsible for the grain size distribution observed experimentally. The effect of the refiner level is also studied.

  8. Process for removal of ammonia and acid gases from contaminated waters

    DOEpatents

    King, C.J.; Mackenzie, P.D.

    1982-09-03

    Contaminating basic gases, i.e., ammonia and acid gases, e.g., carbon dioxide, are removed from process waters or waste waters in a combined extraction and stripping process. Ammonia in the form of ammonium ion is extracted by an immiscible organic phase comprising a liquid cation exchange component, especially an organic phosphoric acid derivative, and preferably di-2-ethyl hexyl phosphoric acid, dissolved in an alkyl hydrocarbon, aryl hydrocarbon, higher alcohol, oxygenated hydrocarbon, halogenated hydrocarbon, and mixtures thereof. Concurrently, the acidic gaseous contaminants are stripped from the process or waste waters by stripping with stream, air, nitrogen, or the like. The liquid cation exchange component has the ammonia stripped therefrom by heating, and the component may be recycled to extract additional amounts of ammonia.

  9. Process for removal of ammonia and acid gases from contaminated waters

    DOEpatents

    King, C. Judson; MacKenzie, Patricia D.

    1985-01-01

    Contaminating basic gases, i.e., ammonia, and acid gases, e.g., carbon dioxide, are removed from process waters or waste waters in a combined extraction and stripping process. Ammonia in the form of ammonium ion is extracted by an immiscible organic phase comprising a liquid cation exchange component, especially an organic phosphoric acid derivative, and preferably di-2-ethyl hexyl phosphoric acid, dissolved in an alkyl hydrocarbon, aryl hydrocarbon, higher alcohol, oxygenated hydrocarbon, halogenated hydrocarbon, and mixtures thereof. Concurrently, the acidic gaseous contaminants are stripped from the process or waste waters by stripping with steam, air, nitrogen, or the like. The liquid cation exchange component has the ammonia stripped therefrom by heating, and the component may be recycled to extract additional amounts of ammonia.

  10. The kinetics of process dependent ammonia inhibition of methanogenesis from acetic acid.

    PubMed

    Wilson, Christopher Allen; Novak, John; Takacs, Imre; Wett, Bernhard; Murthy, Sudhir

    2012-12-01

    Advanced anaerobic digestion processes aimed at improving the methanization of sewage sludge may be potentially impaired by the production of inhibitory compounds (e.g. free ammonia). The result of methanogenic inhibition is relatively high effluent concentrations of acetic acid and other soluble organics, as well as reduced methane yields. An extreme example of such an advanced process is the thermal hydrolytic pretreatment of sludge prior to high solids digestion (THD). Compared to a conventional mesophilic anaerobic digestion process (MAD), THD operates in a state of constant inhibition driven by high free ammonia concentrations, and elevated pH values. As such, previous investigations of the kinetics of methanogenesis from acetic acid under uninhibited conditions do not necessarily apply well to the modeling of extreme processes such as THD. By conducting batch ammonia toxicity assays using biomass from THD and MAD reactors, we compared the response of these communities over a broad range of ammonia inhibition. For both processes, increased inhibitor concentrations resulted in a reduction of biomass growth rate (r(max) = μ(max)∙X) and a resulting decrease in the substrate half saturation coefficient (K(S)). These two parameters exhibited a high degree of correlation, suggesting that for a constant transport limited system, the K(S) was mostly a linear function of the growth rate. After correcting for reactor pH and temperature, we found that the THD and MAD biomass were both able to perform methanogenesis from acetate at high free ammonia concentrations (equivalent to 3-5 g/L total ammonia nitrogen), albeit at less than 30% of their respective maximum rates. The reduction in methane production was slightly less pronounced for the THD biomass than for MAD, suggesting that the long term exposure to ammonia had selected for a methanogenic pathway less dependent on those organisms most sensitive to ammonia inhibition (i.e. aceticlastic methanogens). PMID

  11. UV/chlorine process for ammonia removal and disinfection by-product reduction: comparison with chlorination.

    PubMed

    Zhang, Xinran; Li, Weiguang; Blatchley, Ernest R; Wang, Xiaoju; Ren, Pengfei

    2015-01-01

    The combined application of UV irradiation at 254 nm and chlorination (UV/chlorine process) was investigated for ammonia removal in water treatment. The UV/chlorine process led to higher ammonia removal with less chlorine demand, as compared to breakpoint chlorination. Chlorination of NH₃ led to NH₂Cl formation in the first step. The photolysis of NH₂Cl and radical- mediated oxidation of ammonia appeared to represent the main pathways for ammonia removal. The trivalent nitrogen of ammonia was oxidized, presumably by reactions with aminyl radicals and chlorine radicals. Measured products included NO₃⁻and NO₂⁻; it is likely that N₂ and N₂O were also generated. In addition, UV irradiation appeared to have altered the reactivity of NOM toward free chlorine. The UV/chlorine process had lower chlorine demand, less C-DBPs (THMs and HAAs), but more HANs than chlorination. These results indicate that the UV/chlorine process could represent an alternative to conventional breakpoint chlorination for ammonia-containing water, with several advantages in terms of simplicity, short reaction time, and reduced chemical dosage. PMID:25466638

  12. Ammonia scrubbing

    SciTech Connect

    Epperly, W.R.; Peter-Hoblyn, J.D.; Sullivan, J.C

    1989-05-16

    A process is described for reducing the concentration of ammonia in the effluent from the combustion of a carbonaceous fuel, the process comprising introducing a non-nitrogeneous treatment agent which comprises a paraffinic, olefinic, aromatic oxygenated hydrocarbon into the effluent at a ratio of non-nitrogenous treatment agent to effluent ammonia of about 2:1 to about 200:1 to combine with ammonia present in the effluent, wherein the effluent temperature is about 1350/sup 0/F to about 2000/sup 0/F, and further wherein the non-nitrogenous treatment agent is introduced under conditions effective to perform ammonia scrubbing.

  13. Ammonia Monitor

    NASA Technical Reports Server (NTRS)

    Sauer, Richard L. (Inventor); Akse, James R. (Inventor); Thompson, John O. (Inventor); Atwater, James E. (Inventor)

    1999-01-01

    Ammonia monitor and method of use are disclosed. A continuous, real-time determination of the concentration of ammonia in an aqueous process stream is possible over a wide dynamic range of concentrations. No reagents are required because pH is controlled by an in-line solid-phase base. Ammonia is selectively transported across a membrane from the process stream to an analytical stream to an analytical stream under pH control. The specific electrical conductance of the analytical stream is measured and used to determine the concentration of ammonia.

  14. DM-2 Chilling

    NASA Video Gallery

    How do you chill down 1.4 million pounds of solid rocket fuel in the hot Utah desert? Lots of air conditioning! Learn how ATK chilled down DM-2, the second Ares first stage development motor in adv...

  15. Development of a simultaneous partial nitrification, anaerobic ammonia oxidation and denitrification (SNAD) bench scale process for removal of ammonia from effluent of a fertilizer industry.

    PubMed

    Keluskar, Radhika; Nerurkar, Anuradha; Desai, Anjana

    2013-02-01

    A simultaneous partial nitrification, anammox and denitrification (SNAD) process was developed for the treatment of ammonia laden effluent of a fertilizer industry. Autotrophic aerobic and anaerobic ammonia oxidizing biomass was enriched and their ammonia removal ability was confirmed in synthetic effluent system. Seed consortium developed from these was applied in the treatment of effluent in an oxygen limited bench scale SNAD type (1L) reactor run at ambient temperature (∼30°C). Around 98.9% ammonia removal was achieved with ammonia loading rate 0.35kgNH(4)(+)-N/m(3)day in the presence of 46.6mg/L COD at 2.31days hydraulic retention time. Qualitative and quantitative analysis of the biomass from upper and lower zone of the reactor revealed presence of autotrophic ammonia oxidizing bacteria (AOB), Planctomycetes and denitrifiers as the dominant bacteria carrying out anoxic oxidation of ammonia in the reactor. Physiological and molecular studies strongly indicate presence of anammox bacteria in the anoxic zone of the SNAD reactor. PMID:23313684

  16. Ammonia removal from raw manure digestate by means of a turbulent mixing stripping process.

    PubMed

    Limoli, Alice; Langone, Michela; Andreottola, Gianni

    2016-07-01

    In this study, ammonia stripping by means of a turbulent mixing process followed by pH neutralization was investigated as a simple and cost-effective ammonia removal technique to treat raw manure digestate. Batch tests conducted using CaO, NaOH and H2O2 to control pH and temperature and combinations thereof showed that sodium hydroxide was the most suitable chemical, as it is easy to handle, minimizes treatment time and costs, does not increase the solid content of the sludge and allows to easily control the stripping process. NaOH dosage mainly depended on buffering capacity rather than on total solid content. The analysis of the ammonia stripping process indicated that ammonia removal was strongly dependent on pH, and ammonia removal rate followed the pseudo-first-order kinetics. Total solid content slightly influenced TAN removal efficiency. When NaOH was applied to treat raw digestate at pH 10 and mean temperature of 23 ± 2 °C, TAN removal efficiency reached 88.7% after 24 h of turbulent mixing stripping, without reaching inhibitory salinity levels. Moreover, pH neutralization with sulfuric acid following the stripping process improved raw digestate dewaterability. PMID:27031295

  17. Effect of high pressure processing on textural and microbiological quality of pink perch (Nemipterus japonicus) sausage during chilled storage

    NASA Astrophysics Data System (ADS)

    Kunnath, Sarika; Panda, Satyen Kumar; Jaganath, Bindu; Gudipati, Venkateshwarlu

    2015-10-01

    The non-thermal high pressure (HP) processing was studied on fish sausage to enhance the quality during chilled storage. Pink perch (Nemipterus japonicus) sausages, packed in poly amide casing under vacuum were subjected to 400, 500 and 600 MPa pressures (dwell time: 10 min and ramp rate: 300 MPa/min) and compared with heat-set samples for physico-chemical and microbial quality parameters. Pressurized samples formed softer and glossier gels with a slight reduction in water-holding capacity. HP made the texture of sausage softer, cohesive and less chewy and gummier than heat-treated ones. Folding test seen higher acceptance values in samples treated at 500 and 600 MPa, during storage. Maximum log reduction in microbial count was observed in 600 MPa immediately, and significant difference in cooked and pressurized sausages was seen only up to 7th day. This revealed the potential application of HP in replacing conventional heat treatment for sausages preparation with enhanced shelf-life.

  18. Temperature and bacterial profile of post chill poultry carcasses stored in processing combo held at room temperature.

    PubMed

    Handley, John A; Hanning, Irene; Ricke, Steven C; Johnson, Michael G; Jones, Frank T; Apple, Robert O

    2010-10-01

    Post chill whole poultry carcasses from a commercial processing plant were stored in a processing combo at room temperature (70 °F/21 °C) for 54 h to mimic the scenario of temperature abuse before further processing. Temperature data were collected in 1-min intervals and averaged each hour by 9 temperature data loggers. Two linear regressions were developed for the combo and internal breast temperature and slopes were nearly identical. Microbial data was collected by performing whole bird carcass rinses that were enumerated for aerobic plate count (APC), Enterobacteriaceae, Escherichia coli, and total coliform. Samples were collected from the chiller chute at time zero for initial bacterial counts. Carcass sampling continued once the internal breast temperature achieved 45 °F (7 °C 10 h) and continued every 2 h until the final internal breast temperature was 63 °F (17 °C 54 h). Linear regressions were developed for the first 26 h, which exhibited no statistically significant growth except for Enterobacteriaceae. A 2nd linear regression (28 to 54 h) exhibited significant growth for all analyses. Overall, APC increased from a log(10) colony forming unit (CFU)/mL count of 2.86 to 7.02, Enterobacteriaceae increased from 0.66 to 6.64, coliform increased from 0.72 to 4.81, and E. coli increased from 0.53 to 4.45. Denaturing gradient gel electrophoresis was performed to detect changes in the bacterial populations, which indicated 95% similarity within sampled groups, but the overall percent similarity among samples collected over 54 h was 8%. From the data, microbial growth demonstrates a period of 26 h for minimal growth; therefore, the product could be further processed rather than designated as waste. PMID:21535507

  19. Effect of Ammonia Concentration on Silica Spheres Morphology and Solution Hydroxyl Concentration in Stober Process.

    PubMed

    Zeng, Dejun; Zhang, Haihong; Wang, Bo; Sang, Kezheng; Yang, Jianfeng

    2015-09-01

    Ammonia was used as catalyst to synthesize spherical silica particles by Stober process. More details about the effect of ammonia concentration on the silica powders were investigated. With increase of ammonia concentration from 0.05 to 1.75 mol/L, it was found that particle size increased from 0.068 to 0.91 μm and number density of silica particles decreased rapidly from 9242.40 x 10(10) to 4.62 x 10(10)/mL. Besides, the ratio of standard deviation and the particle size decreased with the increase of ammonia concentration. These results were well consistent with prediction of aggregation model. It was proved that ammonia resulted in persistently high pH values of solutions, which were vital to form large silica spheres. In the formation process of silica spheres, solution hydroxyl concentration was reduced, which might be attributed to transfer of negative charge in hydroxyl groups to silica spheres. PMID:26716345

  20. Effect of Soy Protein Hydrolysates Prepared by Subcritical Water Processing on the Physicochemical Properties of Pork Patty during Chilled Storage

    PubMed Central

    Min, Sang-Gi

    2015-01-01

    The present study was carried out to investigate the effects of soy protein hydrolysates (SPHs) addition on the quality characteristics of pork patties. The SPHs was prepared by subcritical water process (SWP) at 180℃ without holding time and mixed with the pork patty components at varying concentrations (0-3%), and the patties were stored at 4℃ for 14 d. As quality parameters, instrumental color, thiobarbituric acid-reactive substances (TBARS), pH, water holding capacity (WHC) and shear force were measured at the end of storage. Regardless of SPHs concentration, the addition of SPHs significantly manifested low L* and high a* values compared to those of untreated control (p<0.05). For b* value, addition of SPHs in the 0.5-1.5% was unaffected, while >2.0% of SPHs caused significantly lower b* than control (p<0.05). The color changes in pork patties with and without SPHs were also identified in visual appearance where the pork patties containing 0.5-2.0% showed bright red color which was comparable to brownish color of control and patties containing >2.5% SPHs. Lipid oxidation was delayed by the addition of 0.5-1.5% SPHs, while it was accelerated by the addition of 3% SPHs. The pH of patties increased with increasing concentration of SPHs, whereas there were no significant differences in WHC and shear force of patties. Consequently, the results indicated that the addition of 0.5-1.5% SPHs had a potential advantage in suppressing oxidative deterioration of fat-containing meat products during chilled storage. PMID:26761879

  1. Ammonia, Dimethylamine, Trimethylamine, and Trimethylamine Oxide from Raw and Processed Fish By-Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concentrations of ammonia, monomethylamine (MMA), dimethylamine (DMA), trimethylamine (TMA) and trimethylamine oxide (TMAO) in raw and processed fish by-products were determined in cold water marine fish using a capillary electrophoresis (CE) method. The CE method provides a fast and sensitive proce...

  2. Impact of Anaerobic Digestion of Liquid Dairy Manure on Ammonia Volatilization Process

    NASA Astrophysics Data System (ADS)

    Koirala, K.

    2013-12-01

    The goal of this study was to determine the effect of anaerobic digestion (AD) on the mechanism of ammonia volatilization from liquid dairy manure, in storage or treatment lagoon, prior to land application. Physical-chemical properties of liquid dairy manure, which may affect ammonia volatilization process, were determined before and after AD. The properties of interest included: particle size distribution (PSD), total solids (TS), volatile solids (VS), viscosity, pH, total ammoniacal nitrogen (TAN), and ionic strength (IS). The overall mass transfer coefficient of ammonia (KoL) and the NH3 fraction of TAN (β) for the undigested (UD) and AD manures were then experimentally determined in a laboratory convective emission chamber (CEC) at a constant wind speed of 1.5 m s-1 and fixed air temperature of 25 °C at liquid manure temperatures of 15, 25, and 35 °C. The PSD indicated non-normal left skewed distribution for both AD and UD manures particles, suggestive of heavier concentrations of particles towards the lower particle size range. The volume median diameters (VMD) for solids from UD and AD were not significantly different (p= 0.65), but the geometric standard deviations (GSD) were significantly different (p = 0.001), indicating slightly larger particles but more widely distributed solids in UD than AD manure. Results also indicated significantly higher pH, TAN, ionic strength (IS) and viscosity in AD manure. The KoL and β for AD manure determined under identical conditions (air temperature, liquid temperature, and airflow) were significantly higher (p > 0.05) than for UD manure. Overall, these findings suggest that AD of dairy manure significantly increased initial ammonia volatilization potential from liquid dairy manure; with the largest increase (~62%) emanating from increased ammonium dissociation. The initial flux of ammonia, during the experiment period, was ~84% more from AD than in UD dairy manure. Keywords. Process based models, mass transfer

  3. Ammonia removal in the carbon contactor of a hybrid membrane process.

    PubMed

    Stoquart, Céline; Servais, Pierre; Barbeau, Benoit

    2014-12-15

    The hybrid membrane process (HMP) coupling powdered activated carbon (PAC) and low-pressure membrane filtration is emerging as a promising new option to remove dissolved contaminants from drinking water. Yet, defining optimal HMP operating conditions has not been confirmed. In this study, ammonia removal occurring in the PAC contactor of an HMP was simulated at lab-scale. Kinetics were monitored using three PAC concentrations (1-5-10 g L(-1)), three PAC ages (0-10-60 days), two temperatures (7-22 °C), in ambient influent condition (100 μg N-NH4 L(-1)) as well as with a simulated peak pollution scenario (1000 μg N-NH4L(-1)). The following conclusions were drawn: i) Using a colonized PAC in the HMP is essential to reach complete ammonia removal, ii) an older PAC offers a higher resilience to temperature decrease as well as lower operating costs; ii) PAC concentration inside the HMP reactor is not a key operating parameter as under the conditions tested, PAC colonization was not limited by the available surface; iii) ammonia flux limited biomass growth and iv) hydraulic retention time was a critical parameter. In the case of a peak pollution, the process was most probably phosphate-limited but a mixed adsorption/nitrification still allowed reaching a 50% ammonia removal. Finally, a kinetic model based on these experiments is proposed to predict ammonia removal occurring in the PAC reactor of the HMP. The model determines the relative importance of the adsorption and biological oxidation of ammonia on colonized PAC, and demonstrates the combined role of nitrification and residual adsorption capacity of colonized PAC. PMID:25459222

  4. Ammonia Leaching: A New Approach of Copper Industry in Hydrometallurgical Processes

    NASA Astrophysics Data System (ADS)

    Radmehr, Vahid; Koleini, Seyed Mohammad Javad; Khalesi, Mohammad Reza; Tavakoli Mohammadi, Mohammad Reza

    2013-10-01

    Ammonia and ammonium salts have been recognized as effective leaching agents in hydrometallurgical processes due to low toxicity and cost, easy recovery and high selective recovery of metals. New research findings on considerable advantages of leaching by these agents and elimination of problems associated with acid leaching have resulted in a new approach in the world to this method. The investigations in this field indicate more frequent use of this method for extracting copper from ore and concentrate relative to other basic metals. In this paper, an attempt was made to describe the basis and different ammonia leaching methods and present the major research activities in this field for copper. Also latest findings and related novel processes have been presented. Comparisons including assessment of advantages and disadvantages of this method relative to acid leaching method, kinetic study of copper ammonia leaching and evaluation of Eh-pH diagrams in a system containing water and ammonia are other parts of this study. Finally, by describing the studies on copper extraction from the resulting pregnant solutions, the applicable extraction agents have been reviewed.

  5. Pretreatment of rice straw with combined process using dilute sulfuric acid and aqueous ammonia

    PubMed Central

    2013-01-01

    Background Use of lignocellulosic biomass has received attention lately because it can be converted into various versatile chemical compounds by biological processes. In this study, a two-step pretreatment with dilute sulfuric acid and aqueous ammonia was performed efficiently on rice straw to obtain fermentable sugar. The soaking in aqueous ammonia process was also optimized by a statistical method. Results Response surface methodology was employed. The determination coefficient (R2) value was found to be 0.9607 and the coefficient of variance was 6.77. The optimal pretreatment conditions were a temperature of 42.75°C, an aqueous ammonia concentration of 20.93%, and a reaction time of 48 h. The optimal enzyme concentration for saccharification was 30 filter paper units. The crystallinity index was approximately 60.23% and the Fourier transform infrared results showed the distinct peaks of glucan. Ethanol production using Saccharomyces cerevisiae K35 was performed to verify whether the glucose saccharified from rice straw was fermentable. Conclusions The combined pretreatment using dilute sulfuric acid and aqueous ammonia on rice straw efficiently yielded fermentable sugar and achieved almost the same crystallinity index as that of α-cellulose. PMID:23898802

  6. Study of an ammonia-based wet scrubbing process in a continuous flow system

    SciTech Connect

    Mao, James X.; Lee, Anita S.; Kitchin, John R.; Nulwala, Hunaid B.; Luebke, David R.; Damodaran, Krishnan

    2013-01-01

    A continuous gas and liquid flow, regenerative scrubbing process for CO{sub 2} capture was demonstrated at the bench-scale level. An aqueous ammonia-based solution captures CO{sub 2} from simulated flue gas in an absorber and releases a nearly pure stream of CO{sub 2} in the regenerator. After the regeneration, the solution of ammonium compounds is recycled to the absorber. The design of a continuous flow unit was based on earlier exploratory results from a semi-batch reactor, where a CO{sub 2} and N{sub 2} simulated flue gas mixture flowed through a well-mixed batch of ammonia-based solution. During the semi-batch tests, the solution was cycled between absorption and regeneration steps to measure the carrying capacity of the solution at various initial ammonia concentrations and temperatures. Consequentially, a series of tests were conducted on the continuous unit to observe the effect of various parameters on CO{sub 2} removal efficiency and regenerator effectiveness within the flow system. The parameters that were studied included absorber temperature, regenerator temperature, initial NH{sub 3} concentration, simulated flue gas flow rate, liquid solvent inventory in the flow system, and height of the packed-bed absorber. From this testing and subsequent testing, ammonia losses from both the absorption and regeneration steps were quantified, and attempts were made to maintain steady state during operations. Implications of experimental results with respect to process design are discussed.

  7. The chemistry, waste form development, and properties of the Nitrate to Ammonia and Ceramic (NAC) process

    SciTech Connect

    Mattus, A.J.; Lee, D.D.; Youngblood, E.L.; Walker, J.F. Jr.; Tiegs, T.N.

    1994-06-01

    A process for the conversion of alkaline, aqueous nitrate wastes to ammonia gas at low temperature, based upon the use of the active metal reductant aluminum, has been developed at the Oak Ridge National Laboratory (ORNL). The process is also well suited for the removal of low-level waste (LLW) radioelements and hazardous metals which report to the solid, alumina-based by-product. ne chemistry of the interaction of aluminum powders with nitrate, and other waste stream metals is presented.

  8. Enhanced ammonia content in compost leachate processed by black soldier fly larvae.

    PubMed

    Green, Terrence R; Popa, Radu

    2012-03-01

    Black soldier fly (BSF) larvae (Hermetia illucens), feeding on leachate from decaying vegetable and food scrap waste, increase ammonia (NH (4) (+) ) concentration five- to sixfold relative to leachate unprocessed by larvae. NH (4) (+) in larva-processed leachate reached levels as high as ∼100 mM. Most of this NH (4) (+) appears to have come from organic nitrogen within the frass produced by the larvae as they fed on leachate. In nitrate-enriched solutions, BSF larvae also facilitate dissimilatory nitrate reduction to ammonia. The markedly higher concentration of NH (4) (+) recovered in leachates processed with BSF larvae and concomitant diversion of nutrients into insect biomass (itself a valuable feedstock) indicate that the use of BSF larvae in processing leachate of decaying organic waste could be advantageous in offsetting capital and environmental costs incurred in composting. PMID:22238016

  9. A process-based model for ammonia emission from urine patches, GAG (Generation of Ammonia from Grazing): description and sensitivity analysis

    NASA Astrophysics Data System (ADS)

    Móring, Andrea; Vieno, Massimo; Doherty, Ruth M.; Laubach, Johannes; Taghizadeh-Toosi, Arezoo; Sutton, Mark A.

    2016-03-01

    In this paper a new process-based, weather-driven model for ammonia (NH3) emission from a urine patch has been developed and its sensitivity to various factors assessed. The GAG model (Generation of Ammonia from Grazing) is capable of simulating the TAN (total ammoniacal nitrogen) and the water content of the soil under a urine patch and also soil pH dynamics. The model tests suggest that ammonia volatilization from a urine patch can be affected by the possible restart of urea hydrolysis after a rain event as well as CO2 emission from the soil. The vital role of temperature in NH3 exchange is supported by our model results; however, the GAG model provides only a modest overall temperature dependence in total NH3 emission compared with the literature. This, according to our findings, can be explained by the higher sensitivity to temperature close to urine application than in the later stages and may depend on interactions with other nitrogen cycling processes. In addition, we found that wind speed and relative humidity are also significant influencing factors. Considering that all the input parameters can be obtained for larger scales, GAG is potentially suitable for field and regional scale application, serving as a tool for further investigation of the effects of climate change on ammonia emissions and deposition.

  10. Passivation of InGaAs surfaces with an integrated process including an ammonia DECR plasma

    SciTech Connect

    Lescaut, B.; Nissim, Y.I.; Bresse, J.F.

    1996-12-31

    Stable and optimum characteristics of micro-optoelectronic devices and circuits require the passivation of the free surface of the III-V materials. An integrated process using a combination of surface cleaning and photochemical dielectric encapsulation is proposed for passivation. The passivation of InGaAs with a short ammonia plasma cleaning has been obtained. The treated surface has been protected with a photochemical dielectric encapsulation. MIS structures fabricated on treated InGaAs surfaces have shown a low density of interface traps and a small hysteresis. This process is an integration of two cold processes that enable its use at the end of the process fabrication of circuits.

  11. Effects of lactic acid and commercial chilling processes on survival of Salmonella, Yersinia enterocolitica, and Campylobacter coli in pork variety meats.

    PubMed

    King, Amanda M; Miller, Rhonda K; Castillo, Alejandro; Griffin, Davey B; Hardin, Margaret D

    2012-09-01

    Current industry chilling practices with and without the application of 2% L-lactic acid were compared for their effectiveness at reducing levels of Salmonella, Yersinia enterocolitica, and Campylobacter coli on pork variety meats. Pork variety meats (livers, intestines, hearts, and stomachs) were inoculated individually with one of the three pathogens and subjected to five different treatment combinations that included one or more of the following: water wash (25°C), lactic acid spray (2%, 40 to 50°C), chilling (4°C), and freezing (-15°C). Samples were analyzed before treatment, after each treatment step, and after 2, 4, and 6 months of frozen storage. Results showed that when a lactic acid spray was used in combination with water spray, immediate reductions were approximately 0.5 log CFU per sample of Salmonella, 0.8 log CFU per sample of Y. enterocolitica, and 1.1 log CFU per sample of C. coli. Chilling, both alone and in combination with spray treatments, had little effect on pathogens, while freezing resulted in additional 0.5-log CFU per sample reductions in levels of Salmonella and Y. enterocolitica, and an additional 1.0-log CFU per sample reduction in levels of C. coli. While reductions of at least 1 log CFU per sample were observed on variety meats treated with only a water wash and subsequently frozen, samples treated with lactic acid had greater additional reductions than those treated with only a water spray throughout frozen storage. The results of this study suggest that the use of lactic acid as a decontamination intervention, when used in combination with good manufacturing practices during processing, causes significant reductions in levels of Salmonella, Y. enterocolitica, and C. coli on pork variety meats. PMID:22947465

  12. Process for the liquefaction of solid carbonaceous materials wherein nitrogen is separated from hydrogen via ammonia synthesis

    DOEpatents

    Stetka, Steven S.; Nazario, Francisco N.

    1982-01-01

    In a process for the liquefaction of solid carbonaceous materials wherein bottoms residues are upgraded with a process wherein air is employed, the improvement wherein nitrogen buildup in the system is avoided by ammonia synthesis. In a preferred embodiment hydrogen from other portions of the liquefaction process will be combined with hydrogen produced as a result of the bottoms upgrading to increase the H.sub.2 :N.sub.2 ratio in the ammonia reactor.

  13. Pretreatment of corn stover using low-moisture anhydrous ammonia (LMAA) process

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A simple pretreatment method using anhydrous ammonia was developed to minimize water and ammonia inputs for cellulosic ethanol production, termed the low moisture anhydrous ammonia (LMAA) pretreatment. In this method, corn stover with 30 - 70 percent moisture was contacted with anhydrous ammonia in ...

  14. Experimental investigation of the start-up phase during direct chill and low frequency electromagnetic casting of 6063 aluminum alloy processes

    NASA Astrophysics Data System (ADS)

    Wang, Xiangjie; Zhang, Haitao; Zhao, Zhihao; Zhu, Qingfeng; Wang, Gaosong; Jiang, Huixue; Cui, Jianzhong

    2010-06-01

    On the basis of conventional hot-top casting and Casting, Refining and Electromagnetic process, a lower frequency electromagnetic field was applied during the conventional hot-top casting process. Nine thermocouples (type K) were introduced into the metal to study the temperature profile in the ingot during the start-up phase of casting process. The experimental results show that under the effect of the low frequency electromagnetic filed, the heat transfer is changed greatly and the film boiling disappears, which could restrain the formation of fine subsurface cracks; the sump is shallow, and the macrostructure of the ingot butt is fine during the start-up phase of direct chill casting process.

  15. Electrochemical process combined with UV light irradiation for synergistic degradation of ammonia in chloride-containing solutions.

    PubMed

    Xiao, Shuhu; Qu, Jiuhui; Zhao, Xu; Liu, Hujuan; Wan, Dongjin

    2009-03-01

    An electrochemical process combined with ultraviolet light irradiation (UPE) using nonphotoactive dimensionally stable anodes (DSAs) like RuO2/Ti and IrO2/Ti in the presence of chlorides was investigated for ammonia degradation. In this process, the in situ electrogenerated active chlorine and in situ photogenerated chlorine radicals were responsible for the high efficiency of ammonia degradation. More than 97% of ammonia was converted to nitrogen and a significantly synergistic effect was confirmed. Compared with the single electrochemical (E) and photochemical (P) process, the degradation rates of ammonia and the average current efficiencies (ACEs) of the UPE process increased by 1.5 and 1.7 times using RuO2/Ti and IrO2/Ti electrodes, respectively. On the basis of the linear voltammograms, Electrochemical Impedance Spectra (EIS), UV-vis spectra, Electron Spin Resonance (ESR) analysis and a series of experiments designed, the synergistic mechanism was investigated. In addition, this unique process succeeded in transferring the reaction from the electrode surface to the bulk of the solution compared with the conventional photoelectrocatalytic (PEC) process. The loss of chloride decreased from 21.0% to 7.2% and the recycle of chloride was accelerated in the UPE process. Finally the effects of initial pH, current density and ammonia-nitrogen concentration were discussed. Results indicated that pH and ammonia concentration exerted little influences on the degradation rates and current density was the "rate-determining" factor. PMID:19135227

  16. Ultrasonic Treatment Enhanced Ammonia-Oxidizing Bacterial (AOB) Activity for Nitritation Process.

    PubMed

    Zheng, Min; Liu, Yan-Chen; Xin, Jia; Zuo, Hao; Wang, Cheng-Wen; Wu, Wei-Min

    2016-01-19

    Oxidation of ammonia to nitrite rather than nitrate is critical for nitritation process for wastewater treatment. We proposed a promising approach by using controlled ultrasonic treatment to enhance the activity of ammonia-oxidizing bacteria (AOB) and suppress that of nitrite-oxidizing bacteria (NOB). Batch activity assays indicated that when ultrasound was applied, AOB activity reached a peak level and then declined but NOB activity deteriorated continuously as the power intensity of ultrasound increased. Kinetic analysis of relative microbial activity versus ultrasonic energy density was performed to investigate the effect of operational factors (power, sludge concentration, and aeration) on AOB and NOB activities and the test parameters were selected for reactor tests. Laboratory sequential batch reactor (SBR) was further used to test the ultrasonic stimulus with 8 h per day operational cycle and synthetic waste urine as influent. With specific ultrasonic energy density of 0.09 kJ/mg VSS and continuously fed influent containing above 200 mg NH3-N/L, high AOB reproductive activity was achieved and nearly complete conversion of ammonia-N to nitrite was maintained. Microbial structure analysis confirmed that the treatment changed community of AOB, NOB, and heterotrophs. Known AOB Nitrosomonas genus remained at similar level in the biomass while typical NOB Nitrospira genus disappeared in the SBR under ultrasonic treatment and after the treatment was off for 30 days. PMID:26678011

  17. Novel Regenerated Solvent Extraction Processes for the Recovery of Carboxylic Acids or Ammonia from Aqueous Solutions Part II. Recovery of Ammonia from Sour Waters

    SciTech Connect

    Poole, L.J.; King, C.J.

    1990-03-01

    Two novel regenerated solvent extraction processes are examined. The first process has the potential to reduce the energy costs inherent in the recovery of low-volatility carboxylic acids from dilute aqueous solutions. The second process has the potential for reducing the energy costs required for separate recovery of ammonia and acid gases (e.g. CO{sub 2} and H{sub 2}S) from industrial sour waters. The recovery of carboxylic acids from dilute aqueous solution can be achieved by extraction with tertiary amines. An approach for regeneration and product recovery from such extracts is to back-extract the carboxylic acid with a water-soluble, volatile tertiary amine, such as trimethylamine. The resulting trimethylammonium carboxylate solution can be concentrated and thermally decomposed, yielding the product acid and the volatile amine for recycle. Experimental work was performed with lactic acid, SUCCiOlC acid, and fumaric acid. Equilibrium data show near-stoichiometric recovery of the carboxylic acids from an organic solution of Alamine 336 into aqueous solutions of trimethylamine. For fumaric and succinic acids, partial evaporation of the aqueous back extract decomposes the carboxylate and yields the acid product in crystalline form. The decomposition of aqueous solutions of trimethylammonium lactates was not carried out to completion, due to the high water solubility of lactic acid and the tendency of the acid to self-associate. The separate recovery of ammonia and acid gases from sour waters can be achieved by combining steam-stripping of the acid gases with simultaneous removal of ammonia by extraction with a liquid cation exchanger. The use of di-2,4,4-trimethylpentyl phosphinic acid as the liquid cation exchanger is explored in this work. Batch extraction experiments were carried out to measure the equilibrium distribution ratio of ammonia between an aqueous buffer solution and an organic solution of the phosphinic acid (0.2N) in Norpar 12. The concentration

  18. Effect of cooled and chlorinated chiller water on Campylobacter and coliform counts on broiler carcasses during chilling at a middle-size poultry processing plant.

    PubMed

    Kameyama, Mitsuhiro; Chuma, Takehisa; Nishimoto, Tadahiro; Oniki, Hiroyuki; Yanagitani, Yasuo; Kanetou, Ryouichi; Gotou, Kouichi; Shahada, Francis; Iwata, Hiroyuki; Okamoto, Karoku

    2012-01-01

    To evaluate the effect of cooled and chlorinated chill water for Campylobacter and coliforms at a middle-size processing plant which was considered to be difficult for eliminate pathogenic bacteria on carcasses, following three conditions were examined; keeping temperature at < 20, < 10 and < 10°C, and chlorine concentration at < 50, < 50 and 50 to 70 ppm during processing in experiment 1, 2 and 3 respectively. Fifteen prechill and 15 postchill carcasses were examined in each experiment. In lower temperature of experiment 2, decreasing rate (%) of coliforms was significantly higher (P<0.01) than that in experiment 1. In higher chlorination of experiment 3, no Campylobacter was detected from all postchill carcasses. PMID:21897062

  19. Rheological properties of the product slurry of the Nitrate to Ammonia and Ceramic (NAC) process

    SciTech Connect

    Muguercia, I.; Yang, G.; Ebadian, M.A.; Lee, D.D.; Mattus, A.J.; Hunt, R.D.

    1995-03-01

    The Nitrate to Ammonia and Ceramic (NAC) process is an innovative technology for immobilizing the liquid from Low Level radioactive Waste (LLW). An experimental study was conducted to measure the rheological properties of the pipe flow of the NAC product slurry. Test results indicate that the NAC product slurry has a profound rheological behavior. At low solids concentration, the slurry exhibits a typical dilatant fluid (or shear thinning)fluid. The transition from dilatant fluid to pseudo-plastic fluid will occur at between 25% to 30% solids concentration in temperature ranges of 50--80{degree}C. Correlation equations are developed based on the test data.

  20. EXAMINING THE TEMPORAL VARIABILITY OF AMMONIA AND NITRIC OXIDE EMISSIONS FROM AGRICULTURAL PROCESSES

    EPA Science Inventory

    This paper examines the temporal variability of airborne emissions of ammonia from livestock operations and fertilizer application and nitric oxide from soils. In the United States, the livestock operations and fertilizer categories comprise the majority of the ammonia emissions...

  1. Recovery of ammonia in digestates of calf manure through a struvite precipitation process using unconventional reagents.

    PubMed

    Siciliano, A; De Rosa, S

    2014-01-01

    Land spreading of digestates causes the discharge of large quantities of nutrients into the environment, which contributes to eutrophication and depletion of dissolved oxygen in water bodies. For the removal of ammonia nitrogen, there is increasing interest in the chemical precipitation of struvite, which is a mineral that can be reused as a slow-release fertilizer. However, this process is an expensive treatment of digestate because large amounts of magnesium and phosphorus reagents are required. In this paper, a struvite precipitation-based process is proposed for an efficient recovery of digestate nutrients using low-cost reagents. In particular, seawater bittern, a by-product of marine salt manufacturing and bone meal, a by-product of the thermal treatment of meat waste, have been used as low-cost sources of magnesium and phosphorus, respectively. Once the operating conditions are defined, the process enables the removal of more than 90% ammonia load, the almost complete recovery of magnesium and phosphorus and the production of a potentially valuable precipitate containing struvite crystals. PMID:24645466

  2. The Full-Scale Implementation of an Innovative Biological Ammonia Treatment Process

    EPA Science Inventory

    Across the United States, high levels of ammonia in drinking water sources can be found, including small communities like Palo, Iowa (approximate population of 1,026). Although ammonia in water does not pose a direct health concern, ammonia nitrification can cause a number of iss...

  3. Role of osmolytes in adaptation of osmotically stressed and chill-stressed Listeria monocytogenes grown in liquid media and on processed meat surfaces.

    PubMed Central

    Smith, L T

    1996-01-01

    Listeria monocytogenes is a food-borne pathogen that is widely distributed in nature and is found in many kinds of fresh and processed foods. The pervasiveness of this organism is due, in part, to its ability to tolerate environments with elevated osmolarity and reduced temperatures. Previously, we showed that L. monocytogenes adapts to osmotic and chill stress by transporting the osmolyte glycine betaine from the environment and accumulating it intracellularly (R. Ko, L. T. Smith, and G. M. Smith, J. Bacteriol. 176:426-431, 1994). In the present study, the influence of various environmental conditions on the accumulation of glycine betaine and another osmolyte, carnitine, was investigated. Carnitine was shown to confer both chill and osmotic tolerance to the pathogen but was less effective than glycine betaine. The absolute amount of each osmolyte accumulated by the cell was dependent on the temperature, the osmolarity of the medium, and the phase of growth of the culture. L. monocytogenes also accumulated high levels of osmolytes when grown on a variety of processed meats at reduced temperatures. However, the contribution of carnitine to the total intracellular osmolyte concentration was much greater in samples grown on meat than in those grown in liquid media. While the amount of each osmolyte in meat was less than 1 nmol/mg (fresh weight), the overall levels of osmolytes in L. monocytogenes grown on meat were about the same as those in liquid samples, from about 200 to 1,000 nmol/mg of cell protein for each osmolyte. This finding suggests that the accumulation of osmolytes is as important in the survival of L. monocytogenes in meat as it is in liquid media. PMID:8795194

  4. Control of salmonella at the chill tank

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Control of Salmonella on poultry meat should be in the form of a continuous effort from the breeder farm to the fully processed and further processed product, as well as, consumer education. However, control is often measured at the chill tank and efforts are made to relate prevalence to processing...

  5. Process modeling of an advanced NH₃ abatement and recycling technology in the ammonia-based CO₂ capture process.

    PubMed

    Li, Kangkang; Yu, Hai; Tade, Moses; Feron, Paul; Yu, Jingwen; Wang, Shujuan

    2014-06-17

    An advanced NH3 abatement and recycling process that makes great use of the waste heat in flue gas was proposed to solve the problems of ammonia slip, NH3 makeup, and flue gas cooling in the ammonia-based CO2 capture process. The rigorous rate-based model, RateFrac in Aspen Plus, was thermodynamically and kinetically validated by experimental data from open literature and CSIRO pilot trials at Munmorah Power Station, Australia, respectively. After a thorough sensitivity analysis and process improvement, the NH3 recycling efficiency reached as high as 99.87%, and the NH3 exhaust concentration was only 15.4 ppmv. Most importantly, the energy consumption of the NH3 abatement and recycling system was only 59.34 kJ/kg CO2 of electricity. The evaluation of mass balance and temperature steady shows that this NH3 recovery process was technically effective and feasible. This process therefore is a promising prospect toward industrial application. PMID:24850444

  6. Chilling temperatures affect flavor quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomatoes are harvested green in Florida and gassed with ethylene, then stored at chilling temperatures. These chilled temperatures of 12-13ºC can cause a decrease in aroma. Green fruit are more susceptible to chilling injury (CI) which manifests as a pitting of the peel through which decay organisms...

  7. Thermal and energetic processing of ammonia and carbon dioxide bearing solid mixtures.

    PubMed

    Lv, X Y; Boduch, P; Ding, J J; Domaracka, A; Langlinay, T; Palumbo, M E; Rothard, H; Strazzulla, G

    2014-02-28

    We present new experimental results on thermal and ion irradiation processing of frozen ammonia-carbon dioxide mixtures. Some mixtures were deposited at low temperatures (T ≈ 16 K). Upon warming up to 160 K, complex chemical reactions occur leading to the formation of new molecules and, in particular, of ammonium carbamate. We also show that the same species are produced when water is the dominant species in the ternary mixture with ammonia and carbon dioxide. The samples have been irradiated with 144 keV S(9+) ions at 16 K and 50 K. Also in this case, new chemical species are formed as e.g. ammonium formate, CO and OCN(-). The results are discussed in the light of their relevance to the chemical evolution of ices in the interstellar medium and in the solar system. In particular, we suggest searching for them among the gas phase species sublimating from grains around young stellar objects and from the cometary nuclei approaching the Sun. PMID:24358469

  8. Quality and safety of broiler meat in various chilling systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chilling is a critical step in poultry processing to attain high quality meat and to meet the USDA-FSIS temperature standards. This study was conducted to determine the effects of commercially available chilling systems on quality and safety of broiler meat. A total of 300 carcasses in two replica...

  9. An Assessment of the Technical Readiness of the Vapor Phase Catalytic Ammonia Removal Process (VPCAR) Technology

    NASA Technical Reports Server (NTRS)

    Flynn, Michael

    2000-01-01

    This poster provides an assessment of the technical readiness of the Vapor Phase Catalytic Ammonia Removal Process (VPCAR). The VPCAR technology is a fully regenerative water recycling technology designed specifically for applications such as a near term Mars exploration mission. The VPCAR technology is a highly integrated distillation/catalytic oxidation based water processor. It is designed to accept a combined wastewater stream (urine, condensate, and hygiene) and produces potable water in a single process step which requires -no regularly scheduled re-supply or maintenance for a 3 year mission. The technology is designed to be modular and to fit into a volume comparable to a single International Space Station Rack (when sized for a crew of 6). This poster provides a description of the VPCAR technology and a summary of the current performance of the technology. Also provided are the results of two separate NASA sponsored system trade studies which investigated the potential payback of further development of the VPCAR technology.

  10. Biotransformation of pharmaceuticals by ammonia oxidizing bacteria in wastewater treatment processes.

    PubMed

    Xu, Yifeng; Yuan, Zhiguo; Ni, Bing-Jie

    2016-10-01

    Pharmaceutical residues could potentially pose detrimental effects on aquatic ecosystems and human health, with wastewater treatment being one of the major pathways for pharmaceuticals to enter into the environment. Enhanced removal of pharmaceuticals by ammonia oxidizing bacteria (AOB) has been widely observed in wastewater treatment processes. This article reviews the current knowledge on the biotransformation of pharmaceuticals by AOB. The relationship between the pharmaceuticals removal and nitrification process was revealed. The important role of AOB-induced cometabolism on the biotransformation of pharmaceuticals as well as their transformation products and pathways was elucidated. Kinetics and mathematical models describing the biotransformation of pharmaceuticals by AOB were also reviewed. The results highlighted the high degradation capabilities of AOB toward some refractory pharmaceuticals, with their degradations being clearly related to the nitrification rate and their transformation products being identified, which may exhibit similar or higher ecotoxicological impacts compared to the parent compound. PMID:27243932

  11. Mathematical modeling of the evolution of thermal field during start-up phase of the direct chill casting process for AA5182 sheet ingots

    NASA Astrophysics Data System (ADS)

    Sengupta, Joydeep

    The control of the thermal cooling conditions at the start-up phase of the Direct Chill (DC) casting process for aluminum sheet ingots is difficult, and is critical from the standpoint of defect formation. Firstly, boiling water heat transfer governs the secondary cooling experienced by the ingot surfaces as they emerge from the mould. This results in varying rates of heat transfer from the ingot faces as the surface temperature of the ingot changes with time during the start-up phase. Moreover, if the ingot surface temperature at locations below the point of water impingement is high enough to promote film boiling, the water is ejected away from the surface. This can result in a sudden decrease in heat transfer and the formation of local hot spots. Also, the chill water may enter into the gap formed between the ingot base and the bottom block with the evolution of the butt curl. This process of water incursion alters the heat transfer from the base of the ingot, and in turn affects the surface temperature of the ingot faces. A comprehensive mathematical model has been developed to describe heat transfer during the start-up phase of the D.C. casting process. The model, based on the commercial finite element package ABAQUS, includes primary cooling to the mould, secondary cooling to water, and ingot base cooling. The algorithm used to account for secondary cooling to the water includes boiling curves that are a function of surface temperature, water flow rate, impingement point temperature, and position relative to the point of water impingement. In addition, the secondary cooling algorithm accounts for water ejection, which can occur at low water flow rates (low heat extraction rates). The algorithm used to describe ingot base cooling includes the drop in contact heat transfer due to base deformation (butt curl), and also the increase in heat transfer due to the process of water incursion between the ingot base and bottom block. The model has been extensively

  12. A Chilling Experience.

    ERIC Educational Resources Information Center

    Knill, George; Fawcett, George

    1982-01-01

    Wind chill is detailed and noted as an estimate of how cold the wind makes a person feel in cold weather. A worksheet master that provides a table of temperatures and wind speeds is provided along with a set of problems. Answers to the brief question set are provided. (MP)

  13. Chilling requirement of Ribes cultivars

    PubMed Central

    Jones, Hamlyn G.; Gordon, Sandra L.; Brennan, Rex M.

    2015-01-01

    It is usually thought that adequate winter chill is required for the full flowering of many temperate woody species. This paper investigates the sensitivity of blackcurrant bud burst and flowering to natural weather fluctuations in a temperate maritime climate, and compares a range of chill models that have been proposed for assessing the accumulation of winter chill. Bud break for four contrasting cultivars are compared in an exceptionally cold and in a mild winter in Eastern Scotland. The results confirm the importance of chilling at temperatures lower than 0°C and demonstrate that no single chilling function applies equally to all blackcurrant cultivars. There is a pressing need for further model development to take into account the relationship between chilling temperatures and warming temperatures occurring both during and after the chill accumulation period. PMID:25610448

  14. Graphical expression of thermodynamic characteristics of absorption process in ammonia-water system

    NASA Astrophysics Data System (ADS)

    Pospíšil, Jiří; Fortelný, Zdeněk

    2012-04-01

    The adiabatic sorption is very interesting phenomenon that occurs when vapor of refrigerant is in contact with unsaturated liquid absorbent-refrigerant mixture and exchange of heat is forbid between the system and an environment. This contribution introduces new auxiliary lines that enable correct position determination of the adiabatic sorption process in the p-T-x diagram of ammoniawater system. The presented auxiliary lines were obtained from common functions for fast calculation of water-ammonia system properties. Absorption cycles designers often utilize p-t-x diagrams of working mixtures for first suggestion of new absorption cycles. The p-t-x diagrams enable fast correct determination of saturate states of liquid (and gaseous) mixtures of refrigerants and absorbents. The working mixture isn't only at saturated state during a real working cycle. If we know pressure and temperature of an unsaturated mixture, exact position determination is possible in the p-t-x diagrams too.

  15. Thio residue from thermal processing of cometary ices containing carbon disulfide and ammonia

    NASA Astrophysics Data System (ADS)

    Methikkalam, R. R. J.; Pavithraa, S.; Murali Babu, S. P.; Hill, H.; Raja Sekhar, B. N.; Pradeep, T.; Sivaraman, B.

    2016-08-01

    We have carried out experimental investigation on binary ice mixture containing carbon disulfide (CS2) and ammonia (NH3) ices formed at 10 K. Icy films were formed in various combinations to investigate the reactivity of CS2 and NH3 molecules on cometary nucleus. In the case of NH3 ices, deposition carried out at 10 K was found to contain NH3 homo-dimers that was found to reorient upon annealing to 40 K. Phase transition was found to take place as the 10 K ice was warmed to higher temperatures and the phase transition temperature was found to be 5 K higher for the mixed ice in comparison to the layered deposits. Thermal processing of the mixed deposition of CS2sbnd NH3 ice was found to leave thio residue, which could be ammonium dithiocarbamate that was even found to be present at 340 K.

  16. Carcinogenicity study of ammonia-process caramel in F344 rats.

    PubMed

    Maekawa, A; Ogiu, T; Matsuoka, C; Onodera, H; Furuta, K; Tanigawa, H; Hayashi, Y; Odashima, S

    1983-06-01

    The carcinogenicity of ammonia-process caramel, a food colouring, was examined in F344 rats. Caramel was dissolved in distilled water at levels of 0, 1 and 4% and groups of 50 male and 50 female rats were given 20-25 ml of one of these solutions/rat/day as their drinking water for 2 yr. There were no significant differences between the total incidences of tumours or mean survival times of control and experimental groups. A variety of tumours developed in all groups including the control group, and no dose-related effects were found either in the incidence or induction time of tumours in the various organs and tissues except in the pituitary gland of males, in which the incidence of tumours in males given 4% caramel solution was significantly higher than that in controls. Pituitary tumours are among the most common spontaneous tumours in ageing rats of this strain and have a variable incidence. In addition, almost all pituitary tumours detected in males given the 4% solution were microscopic tumours, and there was no significant difference between controls and treated groups in the incidence of hyperplasia or pre-neoplastic lesions in the pituitary gland. These results indicate that the significantly higher incidence of pituitary tumours in males given the 4% caramel solution was not related to caramel administration, but could be explained by the variability of the incidence of spontaneous pituitary tumours. Thus it is concluded that under these experimental conditions ammonia-process caramel was not carcinogenic in F344 rats. PMID:6683219

  17. Stress-Strain Predictions of Semisolid Al-Mg-Mn Alloys During Direct Chill Casting: Effects of Microstructure and Process Variables

    NASA Astrophysics Data System (ADS)

    Jamaly, Nasim; Phillion, A. B.; Drezet, J.-M.

    2013-10-01

    The occurrence of hot tearing during the industrial direct chill (DC) casting process results in significant quality issues and a reduction in productivity. In order to investigate their occurrence, a new semisolid constitutive law (Phillion et al.) for AA5182 that takes into account cooling rate, grain size, and porosity has been incorporated within a DC casting finite element process model for round billets. A hot tearing index was calculated from the semisolid strain predictions from the model. This hot tearing index, along with semisolid stress-strain predictions from the model, was used to perform a sensitivity analysis on the relative effects of microstructural features ( e.g., grain size, coalescence temperature) as well as process parameters ( e.g., casting speed) on hot tearing. It was found that grain refinement plays an important role in the formation of hot cracks. In addition, the combination of slow casting speeds and a low temperature for mechanical coalescence was found to improve hot tearing resistance.

  18. Nut crop yield records show that budbreak-based chilling requirements may not reflect yield decline chill thresholds.

    PubMed

    Pope, Katherine S; Dose, Volker; Da Silva, David; Brown, Patrick H; DeJong, Theodore M

    2015-06-01

    Warming winters due to climate change may critically affect temperate tree species. Insufficiently cold winters are thought to result in fewer viable flower buds and the subsequent development of fewer fruits or nuts, decreasing the yield of an orchard or fecundity of a species. The best existing approximation for a threshold of sufficient cold accumulation, the "chilling requirement" of a species or variety, has been quantified by manipulating or modeling the conditions that result in dormant bud breaking. However, the physiological processes that affect budbreak are not the same as those that determine yield. This study sought to test whether budbreak-based chilling thresholds can reasonably approximate the thresholds that affect yield, particularly regarding the potential impacts of climate change on temperate tree crop yields. County-wide yield records for almond (Prunus dulcis), pistachio (Pistacia vera), and walnut (Juglans regia) in the Central Valley of California were compared with 50 years of weather records. Bayesian nonparametric function estimation was used to model yield potentials at varying amounts of chill accumulation. In almonds, average yields occurred when chill accumulation was close to the budbreak-based chilling requirement. However, in the other two crops, pistachios and walnuts, the best previous estimate of the budbreak-based chilling requirements was 19-32 % higher than the chilling accumulations associated with average or above average yields. This research indicates that physiological processes beyond requirements for budbreak should be considered when estimating chill accumulation thresholds of yield decline and potential impacts of climate change. PMID:25119825

  19. Nut crop yield records show that budbreak-based chilling requirements may not reflect yield decline chill thresholds

    NASA Astrophysics Data System (ADS)

    Pope, Katherine S.; Dose, Volker; Da Silva, David; Brown, Patrick H.; DeJong, Theodore M.

    2015-06-01

    Warming winters due to climate change may critically affect temperate tree species. Insufficiently cold winters are thought to result in fewer viable flower buds and the subsequent development of fewer fruits or nuts, decreasing the yield of an orchard or fecundity of a species. The best existing approximation for a threshold of sufficient cold accumulation, the "chilling requirement" of a species or variety, has been quantified by manipulating or modeling the conditions that result in dormant bud breaking. However, the physiological processes that affect budbreak are not the same as those that determine yield. This study sought to test whether budbreak-based chilling thresholds can reasonably approximate the thresholds that affect yield, particularly regarding the potential impacts of climate change on temperate tree crop yields. County-wide yield records for almond ( Prunus dulcis), pistachio ( Pistacia vera), and walnut ( Juglans regia) in the Central Valley of California were compared with 50 years of weather records. Bayesian nonparametric function estimation was used to model yield potentials at varying amounts of chill accumulation. In almonds, average yields occurred when chill accumulation was close to the budbreak-based chilling requirement. However, in the other two crops, pistachios and walnuts, the best previous estimate of the budbreak-based chilling requirements was 19-32 % higher than the chilling accumulations associated with average or above average yields. This research indicates that physiological processes beyond requirements for budbreak should be considered when estimating chill accumulation thresholds of yield decline and potential impacts of climate change.

  20. Process Modeling of Ammonia Volatilization from Ammonium Solution and Manure Surfaces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia emissions occur from manure surfaces on the barn floor, during storage, and following field application. Based upon theoretical principles and associated published information on ammonia emission, relationships were refined for modeling the dissociation constant (Ka), Henry’s law constant (K...

  1. Process modeling of ammonia volatilization from ammonium solution and manure surfaces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia emissions from animal feeding operations have become an important concern because of their potential effects on animal and human health and the environment. Emissions occur from manure surfaces on the barn floor, during storage, and following field application. To better quantify ammonia emi...

  2. Results of TDLS application for ammonia monitoring in a process of high-purity arsine and phosphine production

    NASA Astrophysics Data System (ADS)

    Kotkov, A. P.; Ivanov, V. A.; Grishnova, N. D.; Shirayev, A. V.; Berezin, A. G.; Nadezhdinskii, A. I.; Ponurovskii, Y. Y.; Popov, I. P.; Shapovalov, Y. P.; Stavrovskii, D. B.; Vyazov, I. E.

    2010-08-01

    Using the TDLS method it has been found that ammonia (NH3) is the main impurity in arsine (AsH3) and phosphine (PH3), produced by hydrolysis of magnesium arsinide and phosphinide, respectively. NH3 behavior is abnormal in solutions of these hydrides: NH3 reveals the properties of a more volatile impurity in relation to arsine and phosphine, although its boiling temperature is higher than that of AsH3 and PH3. The observable anomaly is connected with the fact that in solutions of arsine and phosphine NH3 shows properties differing from the properties of pure ammonia. It was supposed that the influence of intermolecular interaction between ammonia molecules, when diluted by arsine or phosphine, decreases. During the purification of arsine or phosphine one must continuously monitor the NH3.concentration in the extraction of the light fraction in order to define the point at which to terminate the purification process.

  3. ATMOSPHERIC AMMONIA EMISSIONS FROM THE LIVESTOCK SECTOR: DEVELOPMENT AND EVALUATION OF A PROCESS-BASED MODELING APPROACH

    EPA Science Inventory

    We propose multi-faceted research to enhance our understanding of NH3 emissions from livestock feeding operations. A process-based emissions modeling approach will be used, and we will investigate ammonia emissions from the scale of the individual farm out to impacts on region...

  4. Quantum states for quantum processes: A toy model for ammonia inversion spectra

    SciTech Connect

    Arteca, Gustavo A.; Tapia, O.

    2011-07-15

    Chemical transformations are viewed here as quantum processes modulated by external fields, that is, as shifts in reactant to product amplitudes within a quantum state represented by a linear (coherent) superposition of electronuclear basis functions; their electronic quantum numbers identify the ''chemical species.'' This basis set can be mapped from attractors built from a unique electronic configurational space that is invariant with respect to the nuclear geometry. In turn, the quantum numbers that label these basis functions and the semiclassical potentials for the electronic attractors may be used to derive reaction coordinates to monitor progress as a function of the applied field. A generalization of Feynman's three-state model for the ammonia inversion process illustrates the scheme; to enforce symmetry for the entire inversion process model and ensure invariance with respect to nuclear configurations, the three attractors and their basis functions are computed with a grid of fixed floating Gaussian functions. The external-field modulation of the effective inversion barrier is discussed within this conceptual approach. This analysis brings the descriptions of chemical processes near modern technologies that employ molecules to encode information by means of confinement and external fields.

  5. Identification of chilling and heat requirements of cherry trees—a statistical approach

    NASA Astrophysics Data System (ADS)

    Luedeling, Eike; Kunz, Achim; Blanke, Michael M.

    2013-09-01

    Most trees from temperate climates require the accumulation of winter chill and subsequent heat during their dormant phase to resume growth and initiate flowering in the following spring. Global warming could reduce chill and hence hamper the cultivation of high-chill species such as cherries. Yet determining chilling and heat requirements requires large-scale controlled-forcing experiments, and estimates are thus often unavailable. Where long-term phenology datasets exist, partial least squares (PLS) regression can be used as an alternative, to determine climatic requirements statistically. Bloom dates of cherry cv. `Schneiders späte Knorpelkirsche' trees in Klein-Altendorf, Germany, from 24 growing seasons were correlated with 11-day running means of daily mean temperature. Based on the output of the PLS regression, five candidate chilling periods ranging in length from 17 to 102 days, and one forcing phase of 66 days were delineated. Among three common chill models used to quantify chill, the Dynamic Model showed the lowest variation in chill, indicating that it may be more accurate than the Utah and Chilling Hours Models. Based on the longest candidate chilling phase with the earliest starting date, cv. `Schneiders späte Knorpelkirsche' cherries at Bonn exhibited a chilling requirement of 68.6 ± 5.7 chill portions (or 1,375 ± 178 chilling hours or 1,410 ± 238 Utah chill units) and a heat requirement of 3,473 ± 1,236 growing degree hours. Closer investigation of the distinct chilling phases detected by PLS regression could contribute to our understanding of dormancy processes and thus help fruit and nut growers identify suitable tree cultivars for a future in which static climatic conditions can no longer be assumed. All procedures used in this study were bundled in an R package (`chillR') and are provided as Supplementary materials. The procedure was also applied to leaf emergence dates of walnut (cv. `Payne') at Davis, California.

  6. Chemically deposited CdS by an ammonia-free process for solar cells window layers

    SciTech Connect

    Ochoa-Landin, R.; Sastre-Hernandez, J.; Vigil-Galan, O.; Ramirez-Bon, R.

    2010-02-15

    Chemically deposited CdS window layers were studied on two different transparent conductive substrates, namely indium tin oxide (ITO) and fluorine doped tin oxide (FTO), to determine the influence of their properties on CdS/CdTe solar cells performance. Three types of CdS films obtained from different chemical bath deposition (CBD) processes were studied. The three CBD processes employed sodium citrate as the complexing agent in partial or full substitution of ammonia. The CdS films were studied by X-ray diffraction, optical transmission spectroscopy and atomic force microscopy. CdS/CdTe devices were completed by depositing 3 {mu}m thick CdTe absorbent layers by means of the close-spaced vapor transport technique (CSVT). Evaporated Cu-Au was used as the back contact in all the solar cells. Dark and under illumination J-V characteristic and quantum efficiency measurements were done on the CdS/CdTe devices to determine their conversion efficiency and spectral response. The efficiency of the cells depended on the window layer and on the transparent contact with values between 5.7% and 8.7%. (author)

  7. Ammonia removal from wastewaters using natural Australian zeolite. 2. Pilot-scale study using continuous packed column process

    SciTech Connect

    Cooney, E.L.; Booker, N.A.; Shallcross, D.C.; Stevens, G.W.

    1999-10-01

    A pilot-scale process was designed and operated to investigate the continuous removal of ammonia from sewage using natural zeolite from Australia. The process consisted of a fixed-bed ion-exchange system operated in the downflow mode. Evaluation of the pilot process was initially undertaken for ammonia removal from tap water spiked with ammonium chloride to provide performance data in the absence of competing cations. The performance of the pilot process was then assessed using sewage as feed. Breakthrough curves were constructed for a range of treatment flow rates. Existing models for packed bed performance were shown to be able to predict the breakthrough behavior of the process. The results of a study are presented that show that Australian natural zeolite, clinoptilolite, may be successfully employed in a fixed-bed ion-exchange process to achieve high ammonia removal efficiencies from aqueous solution at rates commensurate with sand filtration. The rate of uptake of ammonium by the zeolite is sufficient to support a continuous high rate process.

  8. Photoinduced radical processes on the spinel (MgAl2O4) surface involving methane, ammonia, and methane/ammonia.

    PubMed

    Emeline, A V; Abramkin, D A; Zonov, I S; Sheremetyeva, N V; Rudakova, A V; Ryabchuk, V K; Serpone, N

    2012-05-15

    The present study explored photoinduced radical processes caused by interaction of CH(4) and NH(3) with a photoexcited surface of a complex metal oxide: magnesium-aluminum spinel (MgAl(2)O(4); MAS). UV irradiation of MAS in vacuo yielded V-type color centers as evidenced by the 360 nm band in difference diffuse reflectance spectra. Interaction of these H-bearing molecules with photogenerated surface-active hole states (O(S)(-)•) yielded radical species which on recombination produced more complex molecules (including heteroatomic species) relative to the initial molecules. For the MAS/CH(4) system, photoinduced dissociative adsorption of CH(4) on surface-active hole centers produced •CH(3) radicals that recombined to yield CH(3)CH(3). For MAS/NH(3), a similar dissociative adsorption process led to formation of •NH(2) radicals with formation of NH(2)NH(2) as an intermediate product; continued UV irradiation ultimately yielded N(2). For the mixed MAS/CH(4)/NH(3) system, however, interaction of adsorbed NH(3) and CH(4) on the UV-activated surface of MAS yielded •NH(2) and •CH(3) radicals, respectively, which produced CH(3)-NH(2) followed by loss of the remaining hydrogens to form a surface-adsorbed cyanide, CN(S), species. Recombination of photochemically produced radicals released sufficient energy to re-excite the solid spinel, generating new surface-active sites and a flash luminescence (emission decay time at 520 nm, τ ~ 6 s for the MAS/NH(3) case) referred to as the PhICL effect. PMID:22497296

  9. Ammonia-LCFA synergetic co-inhibition effect in manure-based continuous biomethanation process.

    PubMed

    Wang, Han; Fotidis, Ioannis A; Angelidaki, Irini

    2016-06-01

    In the current study it has been hypothesized that, when organic loading of an anaerobic reactor is increased, the additional cell biomass biosynthesis would capture more ammonia nitrogen and thereby reduce the ammonia toxicity. Therefore, the alleviation of the toxicity of high ammonia levels using lipids (glycerol trioleate-GTO) or carbohydrates (glucose-GLU) as co-substrates in manure-based thermophilic continuous stirred-tank reactors (R(GTO) and R(GLU), respectively) was tested. At 5gNH4(+)-NL(-1), relative methane production of R(GTO) and R(GLU), was 10.5% and 41% compared to the expected uninhibited production, respectively. At the same time control reactor (R(CTL)), only fed with manure, reached 32.7% compared to the uninhibited basis production. Therefore, it seems that using lipids to counteract the ammonia effect in CSTR reactors creates an "ammonia-LCFA (long chain fatty acids) synergetic co-inhibition" effect. Moreover, co-digestion with glucose in R(GLU) was more robust to ammonia toxicity compared to R(CTL). PMID:26985628

  10. Ammonia recycled percolation as a complementary pretreatment to the dilute-acid process

    SciTech Connect

    Wu, Zhangwen, Lee, Y.Y.

    1997-12-31

    A two-stage dilute-acid percolation (DA) was investigated as a pre-treatment method for switchgrass. With use of extremely low acid (0.078 wt% sulfuric acid) under moderate temperature (145-170{degrees}C), hemicellulose in switchgrass was completely solubilized showing no sugar decomposition. The treated switchgrass contained about 70% glucan and 30% lignin. The high lignin content in the treated feedstock raises a concern that it may cause a high enzyme consumption because of irreversible adsorption of cellulose enzymes to lignin. This problem may be amplified in the SSF operation since it is usually run in fed-batch mode and the residual lignin is accumulated. The DA pretreatment was, therefore, combined with the ammonia recycled percolation (ARP) process that has been proven to be effective in delignification. The combined pretreatment essentially fractionated the switchgrass into three major components. The treated feedstock contained about 90% glucan and 10% lignin. The digestibility of these samples was consistently higher than that of DA treated samples. Further study on the interaction of cellulase with xylan and that with lignin has shown that the enzymatic hydrolysis of cellulose is inhibited by lignin as well as xylan. The external xylan was found to be a noncompetitive inhibitor to cellulose hydrolysis. The cellulose used in this study was proven to have the xylanase activity. 23 refs., 8 figs., 4 tabs.

  11. Synthesis and photocatalytic performances of BiVO 4 by ammonia co-precipitation process

    NASA Astrophysics Data System (ADS)

    Yu, Jianqiang; Zhang, Yan; Kudo, Akihiko

    2009-02-01

    This paper reports the preparation and photocatalytic performance of Bismuth vanadate (BiVO 4) by a facile and inexpensive approach. An amorphous BiVO 4 was first prepared by a co-precipitation process from aqueous solutions of Bi(NO 3) 3 and NH 4VO 3 using ammonia. Followed by heating treatment at various temperatures, the amorphous phase converted to crystalline BiVO 4 with a structure between monoclinic and tetragonal scheelite. The crystallization of BiVO 4 occurred at about 523 K, while the nanocrystalline BiVO 4 were formed with a heat-treatment of lower than 673 K. However, when the heat-treatment was carried out at 773 K, the accumulation of nanocrystals to bulk particles was observed. The photocatalytic performances of the materials were investigated by O 2 evolution under visible-light, and MB decomposition under solar simulator. The results demonstrated that the crystalline structure is still the vital factor for the activities of both reactions. However, the crystallinity of BiVO 4 gives a major influence on the activity of O 2 evolution, whereas the surface area, plays an important role for photocatalytic MB decomposition.

  12. Improved temporal resolution in process-based modelling of agricultural soil ammonia emissions

    NASA Astrophysics Data System (ADS)

    Beuning, J. D.; Pattey, E.; Edwards, G.; Van Heyst, B. J.

    An emerging environmental issue in Canada is how to quantify the contribution of agricultural soil emissions of ammonia (NH 3) to environmental pollution. Emission inventories are essential to predict these emissions and their subsequent atmospheric transportation, transformation, and deposition. Due to the high spatial and temporal variability associated with NH 3 emissions, emission inventories based on measurements become expensive and emission factors lose accuracy. Process-based models are capable of accounting for the complex soil interactions, but current models lack temporal refinement and few models consider NH 3 emissions. This paper presents the development of a one-dimensional (vertical), time-dependent model capable of predicting NH 3 emissions from a slurry applied to a bare soil. The model is based on chemical, physical and biological relationships that govern soil heat, moisture, and nitrogen movement. Processes considered include convection, diffusion, decomposition, nitrification, denitrification, and surface to atmosphere transport. The model is tested with experimental data from Agriculture and Agri-Food Canada which conducted NH 3 measurements following application of dairy cattle slurry to a bare field. An investigation into the sensitivity of emissions to pH and slurry infiltration rate is conducted and model predictions are best fit to measurements based on this investigation. Testing demonstrated the model's ability to predict the large NH 3 emissions immediately following application and subsequent emission trends associated with diurnal patterns that emission factors cannot capture. Results showed that model performance could benefit from a more in depth measurement program and empirical or process models of surface pH. Potential exists for the model to become a useful tool in predicting emissions on local, regional, or national scales.

  13. A process-based model for ammonia emission from urine patches, GAG (Generation of Ammonia from Grazing): description, validation and sensitivity analysis

    NASA Astrophysics Data System (ADS)

    Móring, A.; Vieno, M.; Doherty, R. M.; Laubach, J.; Taghizadeh-Toosi, A.; Sutton, M. A.

    2015-07-01

    In this paper a new process-based, weather-driven model for ammonia (NH3) emission from a urine patch has been developed and its sensitivity to various factors assessed. This model, the GAG model (Generation of Ammonia from Grazing) was developed as a part of a suite of weather-driven NH3 exchange models, as a necessary basis for assessing the effects of climate change on NH3 related atmospheric processes. GAG is capable of simulating the TAN (Total Ammoniacal Nitrogen) content, pH and the water content of the soil under a urine patch. To calculate the TAN budget, GAG takes into account urea hydrolysis as a TAN input and NH3 volatilization as a loss. In the water budget, in addition to the water content of urine, precipitation and evaporation are also considered. In the pH module we assumed that the main regulating processes are the dissociation and dissolution equilibria related to the two products of urea hydrolysis: ammonium and bicarbonate. Finally, in the NH3 exchange flux calculation we adapted a canopy compensation point model that accounts for exchange with soil pores and stomata as well as deposition to the leaf surface. We validated our model against measurements, and carried out a sensitivity analysis. The validation showed that the simulated parameters (NH3 exchange flux, soil pH, TAN budget and water budget) are well captured by the model (r > 0.5 for every parameter at p < 0.01 significance level). We found that process-based modelling of pH is necessary to reproduce the temporal development of NH3 emission. In addition, our results suggested that more sophisticated simulation of CO2 emission in the model could potentially improve the modelling of pH. The sensitivity analysis highlighted the vital role of temperature in NH3 exchange; however, presumably due to the TAN limitation, the GAG model currently provides only a modest overall temperature dependence in total NH3 emission compared with the values in the literature. Since all the input parameters

  14. 5A Zirconium Dioxide Ammonia Microsensor Integrated with a Readout Circuit Manufactured Using the 0.18 μm CMOS Process

    PubMed Central

    Lin, Guan-Ming; Dai, Ching-Liang; Yang, Ming-Zhi

    2013-01-01

    The study presents an ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS) process. The integrated sensor chip consists of a heater, an ammonia sensor and a readout circuit. The ammonia sensor is constructed by a sensitive film and the interdigitated electrodes. The sensitive film is zirconium dioxide that is coated on the interdigitated electrodes. The heater is used to provide a working temperature to the sensitive film. A post-process is employed to remove the sacrificial layer and to coat zirconium dioxide on the sensor. When the sensitive film adsorbs or desorbs ammonia gas, the sensor produces a change in resistance. The readout circuit converts the resistance variation of the sensor into the output voltage. The experiments show that the integrated ammonia sensor has a sensitivity of 4.1 mV/ppm. PMID:23503294

  15. Photophosphorylation after Chilling in the Light 1

    PubMed Central

    Wise, Robert R.; Ort, Donald R.

    1989-01-01

    The response of in situ photophosphorylation in attached cucumber (Cucumis sativus L. cv Ashley) leaves to chilling under strong illumination was investigated. A single-beam kinetic spectrophotometer fitted with a clamp-on, whole leaf cuvette was used to measure the flash-induced electrochromic absorbance change at 518 minus 540 nanometers (ΔA518−540) in attached leaves. The relaxation kinetics of the electric field-indicating ΔA518−540 measures the rate of depolarization of the thylakoid membrane. Since this depolarization process is normally dominated by proton efflux through the coupling factor during ATP synthesis, this technique can be used, in conjuction with careful controls, as a monitor of in situ ATP formation competence. Whole, attached leaves were chilled at 5°C and 1000 microeinsteins per square meter per second for up to 6 hours then rewarmed in the dark at room temperature for 30 minutes and 100% relative humidity. Leaf water potential, chlorophyll content, and the effective optical pathlength for the absorption measurements were not affected by the treatment. Light- and CO2-saturated leaf disc oxygen evolution and the quantum efficiency of photosynthesis were inhibited by approximately 50% after 3 hours of light chilling and by approximately 75% after 6 hours. Despite the large inhibition to net photosynthesis, the measurements of ΔA518−540 relaxation kinetics showed photophosphorylation to be largely unaffected by the chilling and light exposure. The amplitude of the ΔA518-540 measures the degree of energization of the photosynthetic membranes and was reduced significantly by chilling in the light. The cause of the decreased energization was traced to impaired turnover of photosystem II. Our measurements showed that the chilling of whole leaves in the light caused neither an uncoupling of photophosphorylation from photosynthetic electron transport nor any irreversible inhibition of the chloroplast coupling factor in situ. The sizeable

  16. Continuous monitoring of ammonia slip in deNOx processes: extending the detection limits of UV spectroscopy

    NASA Astrophysics Data System (ADS)

    Barshad, Yoav; Barshad, Yael S.

    2002-02-01

    Studies have shown that nitrogen oxides released to the atmosphere as a result of combustion processes can be linked to the formation of acid rain and ground level ozone (smog). Several different processes to reduce the amount of NOx (deNOx process) have been developed and applied. A common factor in all is the need to control the ammonia slip below the low PPM levels. The flue gas stream contains ammonia, nitrogen oxides and in some cases sulfur dioxide. These components all absorb UV radiation, and therefore can be monitored by a UV diode array process spectrometer. In some applications, however, the sulfur dioxide concentration in the gas can be too high to allow for the accurate and direct measurements of the ammonia slip. To overcome this difficulty a fast separation cell is utilized to remove the SO2 from the stream prior to measurement. The analyzer measures the spectrum of the almost separated components; the spectra are then analyzed by a multicomponent method to give the concentration of the individual components. Withdrawing a representative sample across the stack is a crucial factor in this application; spatial averaging across the stack is obtained by drawing a sample through 12 holes with non-equal diameters. The spectroscopic methods, separation of stream components, and the in-situ sampling will be discussed.

  17. Ammonia diffusion through Nalophan™ bags.

    PubMed

    Sironi, Selena; Eusebio, Lidia; Dentoni, Licinia; Capelli, Laura; Del Rosso, Renato

    2014-01-01

    The aim of the work is to verify the diffusion rate of ammonia through the Nalophan™ film that constitutes the sampling bag, considering storage times ranging from 1 to 26 h. The ammonia decay over time was evaluated using gas-chromatography for the quantification of ammonia concentration inside the bag. The research assesses the roles of both of ammonia and water concentration gradients at the polymeric film interface on the diffusion process. The results show that both the ammonia concentration gradient and, in a less pronounced way, the water concentration gradient are the main 'engines' of ammonia diffusion. Double bags seem to represent a simple solution for preventing ammonia losses during storage. Another interesting result concerns the role of the bag surface on the ammonia diffusion rate: the higher the surface/volume (S/V) ratio, the higher the ammonia diffusion rate through the polymeric film. PMID:24552718

  18. Use of ammonia to reduce the viscosity of bottoms streams produced in hydroconversion processes

    DOEpatents

    Zaczepinski, Sioma; Billimoria, Rustom M.; Tao, Frank; Lington, Christopher G.; Plumlee, Karl W.

    1984-01-01

    Coal, petroleum residuum and similar carbonaceous feed materials are subjected to hydroconversion in the presence of molecular hydrogen to produce a hydroconversion effluent which is then subjected to one or more separation steps to remove lower molecular weight liquids and produce a heavy bottoms stream containing high molecular weight liquids and unconverted carbonaceous material. The viscosity of the bottoms streams produced in the separation step or steps is prevented from increasing rapidly by treating the feed to the separation step or steps with ammonia gas prior to or during the separation step or steps. The viscosity of the heavy bottoms stream produced in the final separation step is also controlled by treating these bottoms with ammonia gas. In a preferred embodiment of the invention, the effluent from the hydroconversion reactor is subjected to an atmospheric distillation followed by a vacuum distillation and the feeds to these distillations are contacted with ammonia during the distillations.

  19. Microbial ecology and performance of ammonia oxidizing bacteria (AOB) in biological processes treating petrochemical wastewater with high strength of ammonia: effect of Na(2)CO(3) addition.

    PubMed

    Whang, L M; Yang, K H; Yang, Y F; Han, Y L; Chen, Y J; Cheng, S S

    2009-01-01

    This study evaluated nitrification performance and microbial ecology of AOB in a full-scale biological process, powder activated carbon treatment (PACT), and a pilot-scale biological process, moving bed biofilm reactor (MBBR), treating wastewater collected from a petrochemical industry park. The petrochemical influent wastewater characteristics showed a relative low carbon to nitrogen ratio around 1 with average COD and ammonia concentrations of 310 mg/L and 325 mg-N/L, respectively. The average nitrification efficiency of the full-scale PACT process was around 11% during this study. For the pilot-scale MBBR, the average nitrification efficiency was 24% during the Run I operation mode, which provided a slightly better performance in nitrification than that of the PACT process. During the Run II operation, the pH control mode was switched from addition of NaOH to Na(2)CO(3), leading to a significant improvement in nitrification efficiency of 51%. In addition to a dramatic change in nitrification performance, the microbial ecology of AOB, monitored with the terminal restriction fragment length polymorphism (T-RFLP) molecular methodology, was found to be different between Runs I and II. The amoA-based TRFLP results indicated that Nitrosomonas europaea lineage was the dominant AOB population during Run I operation, while Nitrosospira-like AOB was dominant during Run II operation. To confirm the effects of Na(2)CO(3) addition on the nitrification performance and AOB microbial ecology observed in the MBBR process, batch experiments were conducted. The results suggest that addition of Na(2)CO(3) as a pH control strategy can improve nitrification performance and also influence AOB microbial ecology as well. Although the exact mechanisms are not clear at this time, the results showing the effects of adding different buffering chemicals such as NaOH or Na(2)CO(3) on AOB populations have never been demonstrated until this study. PMID:19182331

  20. Chemical additive to enhance antimicrobial efficacy of chlorine and control cross-contamination during immersion chill of broiler carcasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immersion chilling during broiler processing can be a site for cross contamination between the occasional highly contaminated carcass and those that are co-chilled. Chlorine is often used as a chill tank antimicrobial but it can be overcome with heavy organic loads associated with the constant supp...

  1. Influence of Citric Acid on the Pink Color and Characteristics of Sous Vide Processed Chicken Breasts During Chill Storage

    PubMed Central

    Lim, Ki-Won

    2015-01-01

    Chicken breast dipped with citric acid (CA) was treated by sous vide processing and stored in a refrigerated state for 0, 3, 6, 9, and 14 d. A non-dipped control group (CON) and three groups dipped in different concentrations of citric acid concentration were analyzed (0.5%, 0.5CIT; 2.0%, 2CIT and 5.0%, 5CIT; w/v). Cooking yield and moisture content increased due to the citric acid. While the redness of the juice and meat in all groups showed significant increase during storage, the redness of the citric acid groups was reduced compared to the control group (p<0.05). The percentage of myoglobin denaturation (PMD) of the CA groups was also increased according to the level of CA during storage. Total aerobic counts, Enterobacteriaceae counts, volatile basic nitrogen and thiobarbituric acid reactive substances (TBARS) were generally lower in the citric acid-treated samples than in untreated ones, indicating extended shelf life of the cooked chicken breast dipped in citric acid solution. The shear force of the 2CIT and 5CIT groups was significantly lower (p<0.05). The findings indicated positive effects in the physicochemical properties and storage ability of sous vide chicken breast at 2% and 5% citric acid concentrations. PMID:26761885

  2. Welding Using Chilled-Inert-Gas Purging

    NASA Technical Reports Server (NTRS)

    Mcgee, William F.; Rybicki, Daniel J.

    1995-01-01

    Report describes study of fusion welding using chilled inert gas. Marked improvement shown in welding of aluminum using chilled helium gas. Chilling inert gas produces two additional benefits: 1) creation of ultradense inert atmosphere around welds; 2) chilled gas cools metal more quickly down to temperature at which metals not reactive.

  3. Photosynthesis of ammonia

    SciTech Connect

    Mallow, W.A.

    1984-09-24

    This study has demonstrated the technical feasibility of producing ammonia using an innovative technique of combining air, water and sunlight. The technique involves passing moist air over a catalyst-doped, open-celled silica foam bed illuminated by concentrated sunlight. A catalytic reaction results in tounts of ammonia. The work summarized in this report included testing of a pilot (small scale) ammonia production system located on the roof of a Southwest Research Institute (SwRI) Laboratory located in San Antonio, Texas. The system consisted of a catalyst foam bed located in a glass tube about three meters long and 5 centimeters in diameter and mounted on the focal line of a parabolic trough solar collector focused at the sun. The primary active ingredient in the catalyst was titanium dioxide. Moist air was blown through the glass tube, over illuminated catalyst foam bed. A catalytic reaction took place in the foam bed resulting in the production of ammonia gas. The ammonia gas was bubbled through a water scrubber where the ammonia was dissolved. The ammonia concentration in the scrubber water was then measured using chemiluminescence and spectrophotometry techniques to determine the ammonia production rate. Thirty-one tests were conducted in the roof top facility. A number of important process parameters were evaluated. The ammonia production rate from these tests varied from several milligrams per hour to a few micrograms per hour. The tests showed that ammonia production was possible although the yields were relatively low. Several aspects of the process could be improved to increase the yield rates. Specifically, better techniques for illuminating the catalyst with concentrated sunlight and for providing moisture at the catalyst surface should enhance the ammonia production rate. 13 references, 7 figures, 1 table.

  4. Short and long term effects of root and shoot chilling of ransom soybean.

    PubMed

    Musser, R L; Thomas, S A; Kramer, P J

    1983-11-01

    The immediate short term effects on some physiological processes and the long term effects on morphology and reproductive development of root- and shoot-chilled soybeans (Glycine max L. cv Ransom) were studied. Roots or shoots of 16- or 17-day-old plants were chilled at 10 degrees C for one week, and then rewarmed to 25 degrees C. Leaf elongation rate, net CO(2) uptake rate, and stomatal conductance decreased during root or shoot chilling. Root chilling had only temporary effects on water relations, while shoot chilling caused large changes in potentials during chilling. Most processes measured returned to control levels after two days of rewarming. Root-chilled plants harvested 90 days after emergence were similar in morphology and seed weight to controls. Shoot-chilled plants showed a large increase over controls in axillary branch growth, but an early abortion of flowers and a delayed resumption of flowering caused a 78% reduction in seed weight. Root chilling in this study was found to have little or no long term effect on the plants, while shoot chilling caused significant changes in vegetative morphology, and a delay in flowering and subsequent pod filling. PMID:16663300

  5. A low-temperature process for the denitration of Hanford single-shell tank, nitrate-based waste utilizing the nitrate to ammonia and ceramic (NAC) or nitrate to ammonia and glass (NAG) process: Phase 2 report

    SciTech Connect

    Mattus, A.J.; Walker, J.F. Jr.; Youngblood, E.L.; Farr, L.L.; Lee, D.D.; Dillow, T.A.; Tiegs, T.N.

    1994-12-01

    Continuing benchtop studies using Hanford single-shell tank (SST) simulants and actual Oak Ridge National Laboratory (ORNL) low-level waste (LLW), employing a new denitration process for converting nitrate to ammonia and ceramic (NAC), have conclusively shown that between 85 and 99% of the nitrate can be readily converted to gaseous ammonia. In this process, aluminum powders can be used to convert alkaline, nitrate-based supernate to ammonia and an aluminum oxide-sodium aluminate-based solid. The process may be able to use contaminated aluminum scrap metal from DOE sites to effect the conversion. The final, nitrate-free ceramic product can be pressed and sintered like other ceramics or silica and/or fluxing agents can be added to form a glassy ceramic or a flowable glass product. Based upon the starting volumes of 6.2 and 3.1 M sodium nitrate solution, volume reductions of 50 to 70% were obtained for the waste form produced. Sintered pellets produced from supernate from Melton Valley Storage Tanks (MVSTs) have been leached in accordance with the 16.1 leach test for the radioelements {sup 85}Sr and {sup 137}Cs. Despite lengthy counting times, {sup 85}Sr could not be detected in the leachates. {sup 137}Cs was only slightly above background and corresponded to a leach index of 12.2 to 13.7 after 8 months of leaching. Leach testing of unsintered and sintered reactor product spiked with hazardous metals proved that both sintered and unsintered product passed the Toxicity Characteristic Leaching Procedure (TCLP) test. Design of the equipment and flowsheet for a pilot demonstration-scale system to prove the nitrate destruction portion of the NAC process and product formation is under way.

  6. Investigation of nitriding and reduction processes in a nanocrystalline iron-ammonia-hydrogen system at 350 °C.

    PubMed

    Bartłomiej, Wilk; Arabczyk, Walerian

    2015-08-21

    In this paper, the series of phase transitions occurring during the gaseous nitriding of nanocrystalline iron was studied. The nitriding process of nanocrystalline iron and the reduction process of the obtained nanocrystalline iron nitrides were carried out at 350 °C in a tubular differential reactor equipped with systems for thermogravimetric measurements and analysis of gas phase composition. The samples were reduced with hydrogen at 500 °C in the above mentioned reactor. Then the sample was nitrided at 350 °C in a stream of ammonia-hydrogen mixtures of various nitriding potentials, P = pNH3/pH2(3/2). At each nitriding potential stationary states were obtained - the nitriding reaction rate is zero and the catalytic ammonia decomposition reaction rate is constant. The reduction process of the obtained nanocrystalline iron nitrides was studied at 350 °C in the stationary states as well. The phase composition of products obtained in both reaction directions (nitriding and reduction) was different despite the identical concentration of nitrogen in the nitriding mixture. The hysteresis phenomenon, occurring at the iron nitriding degree - nitriding potential system, was explained. In the single-phase areas of α-Fe(N), γ'-Fe4N or ε-Fe3-2N, a state of chemical equilibrium between the ammonia-hydrogen mixture, nanocrystalline iron surface and volume was observed. In the multi-phase areas, between the gas phase and the iron surface a state of chemical equilibrium holds, but between the gas phase and solid phase volume a state of quasi-equilibrium exists. The model of the nitriding process of nanocrystalline iron to iron nitride (γ'-Fe4N) was presented. It was found that nanocrystallites reacted in the order of their sizes from the largest to the smallest. PMID:26182186

  7. Impact of Added Sand on the Recovery of Salmonella, Campylobacter, Escherichia coli, and Coliforms from Pre-Chill and Post-Chill Broiler Carcass Halves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to evaluate the use of sand to a rinse for bacterial enumeration and determining the incidence of pathogens from broiler carcasses. During each of 4 replications, 6 pre-chill and 6 post-chill broiler carcasses were collected from a commercial processing plant. All carcasses wer...

  8. Impact of the sampling method and chilling on the Salmonella recovery from pig carcasses.

    PubMed

    Vanantwerpen, Gerty; De Zutter, Lieven; Berkvens, Dirk; Houf, Kurt

    2016-09-01

    Differences in recovery of Salmonella on pig carcasses using non-destructive and destructive sampling methods is not well understood in respect to the chilling processes applied in slaughterhouses. Therefore, in two slaughterhouses, four strains at two different concentrations were inoculated onto pork skin. Inoculated skin samples were sampled before and after chilling with two sampling methods: swabbing and destruction. Both slaughterhouses were visited three times and all tests were performed in triplicate. All samples were analysed using the ISO-method and recovered isolates were confirmed by PFGE. The chilling system (fast or conventional cooling) nor the sampling step (before and after chilling) did not significantly influence the recovery of Salmonella. However, swabbing after chilling leads to an underestimation of the real number of contaminated carcasses. Therefore, destructive sampling is the more designated sampling method after chilling. PMID:27236225

  9. An Evaluation of the Vapor Phase Catalytic Ammonia Removal Process for Use in a Mars Transit Vehicle

    NASA Technical Reports Server (NTRS)

    Flynn, Michael; Borchers, Bruce

    1998-01-01

    An experimental program has been developed to evaluate the potential of the Vapor Phase Catalytic Ammonia Reduction (VPCAR) technology for use as a Mars Transit Vehicle water purification system. Design modifications which will be required to ensure proper operation of the VPCAR system in reduced gravity are also evaluated. The VPCAR system is an integrated wastewater treatment technology that combines a distillation process with high temperature catalytic oxidation. The distillation portion of the system utilizes a vapor compression distillation process to provide an energy efficient phase change separation. This portion of the system removes any inorganic salts and large molecular weight, organic contaminates, i.e., non-volatile, from the product water stream and concentrates these contaminates into a byproduct stream. To oxidize the volatile organic compounds and ammonia, a vapor phase, high temperature catalytic oxidizer is used. This catalytic system converts these compounds along with the aqueous product into CO2, H2O, and N2O. A secondary catalytic bed can then be used to reduce the N2O to nitrogen and oxygen (although not evaluated in this study). This paper describes the design specification of the VPCAR process, the relative benefits of its utilization in a Mars Transit Vehicle, and the design modification which will be required to ensure its proper operation in reduced gravity. In addition, the results of an experimental evaluation of the processors is presented. This evaluation presents the processors performance based upon product water purity, water recovery rates, and power.

  10. Process-based modelling of ammonia emission over a urine patch - Towards developing a field scale emission model for regional use

    NASA Astrophysics Data System (ADS)

    Moring, Andrea; Vieno, Massimo; Doherty, Ruth; Sutton, Mark A.

    2014-05-01

    This work investigates the influence of meteorological factors on ammonia related atmospheric processes, with a special focus on emission from grazing. For this purpose we are developing a process-based model (GAG: Generation of Ammonia from Grazing) driven by meteorology that can simulate the ammonia emission from a field covered by urine patches. The aim of this work is to implement the GAG model into the EMEP atmospheric chemical transport model (ACTM), and examine the changes of surface ammonia concentrations under future climate scenarios. The research is carried out within the framework of the ECLAIRE project (Effects of Climate Change on Air Pollution and Response Strategies for European Ecosystems). To estimate the sensitivity of surface concentrations of ammonia to a temperature dependent emission approach, we applied a temperature function in the EMEP model for the agricultural ammonia emissions from the UK. With the original emissions the resulting surface ammonia concentration has a bimodal seasonal tendency, with a peak in the beginning of the spring when agricultural management starts and with a second maximum during the autumn when fertilizer is typically spread. With our new temperature dependent approach the seasonal cycle became unimodal with a peak in June. This significant difference supports the need for a dynamic emission approach in ACTMs. The GAG model currently works for a single urine patch. Before it calculates the ammonia emission flux over the urine patch the model simulates the ammoniacal nitrogen budget and the water budget under the patch. The preliminary results for emission fluxes are in good agreement with the measurements. However, the differences highlight that further improvements are necessary.

  11. Ammonia mobility in chabazite: insight into the diffusion component of the NH3-SCR process.

    PubMed

    O'Malley, Alexander J; Hitchcock, Iain; Sarwar, Misbah; Silverwood, Ian P; Hindocha, Sheena; Catlow, C Richard A; York, Andrew P E; Collier, P J

    2016-06-29

    The diffusion of ammonia in commercial NH3-SCR catalyst Cu-CHA was measured and compared with H-CHA using quasielastic neutron scattering (QENS) and molecular dynamics (MD) simulations to assess the effect of counterion presence on NH3 mobility in automotive emission control relevant zeolite catalysts. QENS experiments observed jump diffusion with a jump distance of 3 Å, giving similar self-diffusion coefficient measurements for both Cu- and H-CHA samples, in the range of ca. 5-10 × 10(-10) m(2) s(-1) over the measured temperature range. Self-diffusivities calculated by MD were within a factor of 6 of those measured experimentally at each temperature. The activation energies of diffusion were also similar for both studied systems: 3.7 and 4.4 kJ mol(-1) for the H- and Cu-chabazite respectively, suggesting that counterion presence has little impact on ammonia diffusivity on the timescale of the QENS experiment. An explanation is given by the MD simulations, which showed the strong coordination of NH3 with Cu(2+) counterions in the centre of the chabazite cage, shielding other molecules from interaction with the ion, and allowing for intercage diffusion through the 8-ring windows (consistent with the experimentally observed jump length) to carry on unhindered. PMID:27306298

  12. Removal of ammonium chloride generated by ammonia slip from the SNCR process in municipal solid waste incinerators.

    PubMed

    Hwang, In-Hee; Minoya, Hiroshi; Matsuto, Toshihiko; Matsuo, Takayuki; Matsumoto, Akihiro; Sameshima, Ryoji

    2009-03-01

    The selective non-catalytic reduction (SNCR) process is one of the methods used to reduce NO(x) to N(2) and H(2)O by injecting NH(3) or urea solution into a high-temperature furnace. Merits of this method include simple handling, low cost, and energy savings. However, a critical problem of the SNCR process is the generation of ammonia slip; in reactions with HCl in flue gas, ammonium chloride is generated and forms detached white plumes near the stack. Using a laboratory-scale experimental apparatus, we examined the possibility of NH(4)Cl collection and removal by a bag filter (BF). The molar NH(3)/HCl ratio of the compound collected at the filter was nearly one, regardless of gas temperature, retention time, and concentration, confirming the formation of NH(4)Cl. The NH(4)Cl generation ratio increased as reaction temperature decreased, indicating that the collection efficiency of NH(4)Cl should increase if the BF is operated at the lowest possible temperature while avoiding the critical point causing low-temperature corrosion (e.g., 150 degrees C). In addition, the use of activated carbon injection in the front of the BF and the dust layer on the BF are expected to capture slipped ammonia at the BF and reduce NH(4)Cl fume generation in the stack. PMID:19108871

  13. Synthesis of D- and L-phenylalanine derivatives by phenylalanine ammonia lyases: a multienzymatic cascade process.

    PubMed

    Parmeggiani, Fabio; Lovelock, Sarah L; Weise, Nicholas J; Ahmed, Syed T; Turner, Nicholas J

    2015-04-01

    The synthesis of substituted D-phenylalanines in high yield and excellent optical purity, starting from inexpensive cinnamic acids, has been achieved with a novel one-pot approach by coupling phenylalanine ammonia lyase (PAL) amination with a chemoenzymatic deracemization (based on stereoselective oxidation and nonselective reduction). A simple high-throughput solid-phase screening method has also been developed to identify PALs with higher rates of formation of non-natural D-phenylalanines. The best variants were exploited in the chemoenzymatic cascade, thus increasing the yield and ee value of the D-configured product. Furthermore, the system was extended to the preparation of those L-phenylalanines which are obtained with a low ee value using PAL amination. PMID:25728350

  14. Identification of chilling and heat requirements of cherry trees--a statistical approach.

    PubMed

    Luedeling, Eike; Kunz, Achim; Blanke, Michael M

    2013-09-01

    Most trees from temperate climates require the accumulation of winter chill and subsequent heat during their dormant phase to resume growth and initiate flowering in the following spring. Global warming could reduce chill and hence hamper the cultivation of high-chill species such as cherries. Yet determining chilling and heat requirements requires large-scale controlled-forcing experiments, and estimates are thus often unavailable. Where long-term phenology datasets exist, partial least squares (PLS) regression can be used as an alternative, to determine climatic requirements statistically. Bloom dates of cherry cv. 'Schneiders späte Knorpelkirsche' trees in Klein-Altendorf, Germany, from 24 growing seasons were correlated with 11-day running means of daily mean temperature. Based on the output of the PLS regression, five candidate chilling periods ranging in length from 17 to 102 days, and one forcing phase of 66 days were delineated. Among three common chill models used to quantify chill, the Dynamic Model showed the lowest variation in chill, indicating that it may be more accurate than the Utah and Chilling Hours Models. Based on the longest candidate chilling phase with the earliest starting date, cv. 'Schneiders späte Knorpelkirsche' cherries at Bonn exhibited a chilling requirement of 68.6 ± 5.7 chill portions (or 1,375 ± 178 chilling hours or 1,410 ± 238 Utah chill units) and a heat requirement of 3,473 ± 1,236 growing degree hours. Closer investigation of the distinct chilling phases detected by PLS regression could contribute to our understanding of dormancy processes and thus help fruit and nut growers identify suitable tree cultivars for a future in which static climatic conditions can no longer be assumed. All procedures used in this study were bundled in an R package ('chillR') and are provided as Supplementary materials. The procedure was also applied to leaf emergence dates of walnut (cv. 'Payne') at Davis, California. PMID

  15. Cross effect of temperature, pH and free ammonia on autotrophic denitrification process with sulphide as electron donor.

    PubMed

    Fajardo, Carmen; Mora, Mabel; Fernández, Isaac; Mosquera-Corral, Anuska; Campos, José Luis; Méndez, Ramón

    2014-02-01

    Autotrophic denitrification is a suitable technology to simultaneously remove oxidised nitrogen compounds and reduced sulphur compounds yielding nitrogen gas, sulphur and sulphate as the main products. In this work, several batch tests were conducted to investigate the cross effect of temperature, pH and free ammonia on the autotrophic denitrification. Denitrification efficiencies above 95% were achieved at 35°C and pH 7.5-8.0 with maximum specific autotrophic denitrifying activities up to 188mgN2g(-1)VSSd(-1). Free ammonia did not show any effect on denitrification at concentrations up to 53mg NH3-NL(-1). Different sulphide concentrations were also tested with stoichiometric nitrite and nitrate concentrations. Sulphide inhibited denitrification at concentrations higher than 200mgS(2-)L(-1). A 50% inhibition was also found at nitrite concentrations above 48mg NO2(-)-NL(-1). The maximum specific activity decreased until a value of 25mgN2g(-1) VSSd(-1) at 232mg NO2(-)-NL(-1). The Haldane model was used to describe denitrification inhibition caused by nitrite. Kinetic parameters determined from the fitting of experimental data were rmax=176mgN2g(-1)VSSd(-1), Ks=10.7mg NO2(-)-NL(-1) and Ki=34.7mg NO2(-)-NL(-1). The obtained model allowed optimising an autotrophic denitrification process by avoiding situations of inhibition and thus obtaining higher denitrification efficiencies. PMID:24216266

  16. Effect of Immersion or Dry Chilling on Broiler Carcass Moisture Retention and Breast Fillet Functionality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to investigate the effect of chilling method on broiler carcass skin color, carcass moisture retention, and breast fillet quality and functionality. One hundred fifty eviscerated broilers carcasses were removed from a commercial processing line prior to chilling, transported to...

  17. Salmonella recovery following air chilling for matched neck-skin and whole carcass sampling methodologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prevalence and serogroups of Salmonella recovered following air chilling were determined for both enriched neck skin and matching enriched whole carcass samples. Commercially processed and eviscerated carcasses were air chilled to 4C before removing the neck skin (8.3 g) and stomaching in 83 mL...

  18. Effect of chilling method and post-mortem aging time on broiler breast fillet quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to determine the effects of chilling method and post-mortem aging time on broiler breast fillet quality. One hundred-fifty eviscerated broiler carcasses were removed from a commercial processing line prior to chilling and transported to the laboratory. Half of the carcasses we...

  19. Salmonella Recovery Following Immersion Chilling for Matched Neck Skin and Whole Carcass Enrichment Sampling Methodologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prevalence and serogroups of Salmonella recovered following immersion chilling were determined for both neck skin and the matching whole carcass enriched samples. Commercially processed and eviscerated broiler carcasses were immersion chilled in ice and tap water for 40 min. Following immersio...

  20. Putative paternal factors controlling chilling tolerance in Korean market-type cucumber (Cucumis sativus L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chilling temperatures (<10 degrees C) may cause damage to Korean market-type cucumber (Cucumis sativus L.) plants during winter and early spring growing seasons. Inheritance to chilling in U.S. processing cucumber is controlled by cytoplasmic (maternally) and nuclear factors. To understand inherit...

  1. Effects of Dry Chilling on the Microflora on Beef Carcasses at a Canadian Beef Packing Plant.

    PubMed

    Liu, Y; Youssef, M K; Yang, X

    2016-04-01

    The aim of this study was to determine the course of effects on the microflora on beef carcasses of a commercial dry chilling process in which carcasses were dry chilled for 3 days. Groups of 25 carcasses selected at random were sampled when the chilling process commenced and after the carcasses were chilled for 1, 2, 4, 6, 8, 24, and 67 h for determination of the numbers of aerobes, coliforms, and Escherichia coli. The temperatures of the surfaces and the thickest part of the hip (deep leg) of carcasses, as well as the ambient air conditions, including air temperature, velocity, and relative humidity (RH), were monitored throughout the chilling process. The chiller was operated at 0°C with an off-coil RH of 88%. The air velocity was 1.65 m/s when the chiller was loaded. The initial RH levels of the air in the vicinity of carcasses varied with the locations of carcasses in the chiller and decreased rapidly during the first hour of chilling. The average times for shoulder surfaces, rump surfaces, and the deep leg of carcasses to reach 7°C were 13.6 ± 3.1, 16.0 ± 2.4 and 32.4 ± 3.2 h, respectively. The numbers of aerobes, coliforms, and E. coli on carcasses before chilling were 5.33 ± 0.42, 1.95 ± 0.77, 1.42 ± 0.78 log CFU/4,000 cm(2), respectively. The number of aerobes on carcasses was reduced by 1 log unit each in the first hour of chilling and in the subsequent 23 h of chilling. There was no significant difference (P > 0.05) between the numbers of aerobes recovered from carcasses after 24 and 67 h of chilling. The total numbers (log CFU/100,000 cm(2)) on carcasses before chilling and after the first hour of chilling were 3.86 and 2.24 for coliforms and 3.30 and 2.04 for E. coli. The subsequent 23 h of chilling reduced the numbers of both groups of organisms by a further log unit. No coliforms or E. coli were recovered after 67 h of chilling. The findings show that the chilling regime investigated in this study resulted in significant reductions of all

  2. Endogenous salicylic acid accumulation is required for chilling tolerance in cucumber (Cucumis sativus L.) seedlings.

    PubMed

    Dong, Chun-Juan; Li, Liang; Shang, Qing-Mao; Liu, Xin-Yan; Zhang, Zhi-Gang

    2014-10-01

    Salicylic acid (SA) is an important plant hormone, and its exogenous application can induce tolerance to multiple environmental stresses in plants. In this study, we examine the potential involvement of endogenous SA in response to chilling in cucumber (Cucumis sativus L.) seedlings. A low temperature of 8 °C induces a moderate increase in endogenous SA levels. Chilling stimulates the enzymatic activities and the expression of genes for phenylalanine ammonia-lyase (PAL) and benzoic acid-2-hydroxylase rather than isochorismate synthase. This indicates that the PAL enzymatic pathway contributes to chilling-induced SA production. Cucumber seedlings pretreated with SA biosynthesis inhibitors accumulate less endogenous SA and suffer more from chilling damage. The expression of cold-responsive genes is also repressed by SA inhibitors. The reduction in stress tolerance and in gene expression can be restored by the exogenous application of SA, confirming the critical roles of SA in chilling responses in cucumber seedlings. Furthermore, the inhibition of SA biosynthesis under chilling stress results in a prolonged and enhanced hydrogen peroxide (H2O2) accumulation. The application of exogenous SA and the chemical scavenger of H2O2 reduces the excess H2O2 and alleviates chilling injury. In contrast, the protective effects of SA are negated by foliar spraying with high concentrations of H2O2 and an inhibitor of the antioxidant enzyme. These results suggest that endogenous SA is required in response to chilling stress in cucumber seedlings, by modulating the expression of cold-responsive genes and the precise induction of cellular H2O2 levels. PMID:25034826

  3. Quality and bacteriological consequences of beef carcass spray-chilling: Effects of spray duration and boxed beef storage temperature.

    PubMed

    Greer, G G; Jones, S D

    1997-01-01

    The effects of water spray-chilling on beef carcass traits and muscle quality, bacteriology and retail case life were determined in a research abattoir. Chilling treatments were compared using 10 crossbred steer carcasses (280 ± 4 kg) at each spray duration (4, 8, 12 and 16 h) and each vacuum storage temperature (1, 4, 8 and 12 °C). Control sides were air-chilled (1 °C, 24 h) while spray-chilled sides were sprayed with an intermittent water mist at 1 °C in four, 60 s cycles/h for the initial 4-16 h of chilling. The effects of storage temperature were evaluated using vacuum packaged longissimus thoracis (LT) muscle at post-chill intervals of 2, 16, 30 and 44 days. Chilling treatment effects were similar at all spray-chill durations and LT vacuum storage times and temperatures. Carcass spray-chilling did not effect pH, lean colour, % moisture, sarcomere length, shear value or weight loss during the vacuum storage of LT muscle. Carcass fat colour tended to brighten as spray duration was extended up to 12 h, but there was a grey discoloration of fat at spray durations beyond 12 h. Chilling treatment had only marginal effects on anaerobic bacteria during the vacuum storage of LT muscles, or aerobic bacteria during the retail display of rib-eye steaks, and the retail case life of steaks was largely unaffected by spray-chilling. A linear relationship between spray-chill duration and carcass weight loss was determined and carcass shrinkage was reduced by 0.08 g/100 g for every hour of spray-chilling. It was estimated that a major beef processing abattoir could utilize spray-chilling to save more than 2000 kg daily in carcass shrinkage, without compromising quality or increasing spoilage losses. PMID:22061138

  4. Convective heat transfer behavior of the product slurry of the nitrate to ammonia and ceramic (NAC) process

    SciTech Connect

    Muguercia, I.; Yang, G.; Ebadian, M.A.; Lee, D.D.; Mattus, A.J.; Hunt, R.D.

    1995-12-01

    The Nitrate to Ammonia and Ceramic (NAC) process is an innovative technology for immobilizing liquid form low level radioactive waste (LLW). An experimental study has been conducted to measure the heat transfer properties of the NAC product slurry. The results indicate that the heat transfer coefficient for both concentration slurries is much higher than that of pure water, which may be due to the higher conductivity of the gibbsite powder. For the 20% concentration slurry, the heat transfer coefficient increased as the generalized Reynolds number and slurry temperature increased. The heat transfer coefficient of 40% is a function of the Reynolds number only. The test results also indicate that the thermal entrance region can be observed only when the generalized Reynolds number is smaller than 1,000. The correlation equation is also developed based on the experimental data in this paper.

  5. Effect of pelleting process variables on physical properties and sugar yields of ammonia fiber expansion pretreated corn stover

    SciTech Connect

    Amber N. Hoover; Jaya Shankar Tumuluru; Farzaneh Teymouri; Garold L. Gresham; Janette Moore

    2014-07-01

    Pelletization process variables including grind size (4, 6 mm), die speed (40, 50, 60 Hz), and preheating (none, 70 degrees C) were evaluated to understand their effect on pellet quality attributes and sugar yields of ammonia fiber expansion (AFEX) pretreated biomass. The bulk density of the pelletized AFEX corn stover was three to six times greater compared to untreated and AFEX-treated corn stover. Also the durability of the pelletized AFEX corn stover was >97.5% for all pelletization conditions studied except for preheated pellets. Die speed had no effect on enzymatic hydrolysis sugar yields of pellets. Pellets produced with preheating or a larger grind size (6 mm) had similar or lower sugar yields. Pellets generated with 4 mm AFEX-treated corn stover, a 60 Hz die speed, and no preheating resulted in pellets with similar or greater density, durability, and sugar yields compared to other pelletization conditions.

  6. Alternative E ammonia feedstock

    SciTech Connect

    Lentz, M.J.; Wright, R.A.

    1999-07-01

    Power plants are using more Ammonia for increasing precipitator and baghouse efficiency, for SCR and SNCR processes, and for controlling acid stack plumes and dewpoint corrosion. These simple systems inject ammonia and air into the furnace or the precipitator or baghouse inlet ductwork. The common feedstocks in use today are Anhydrous ammonia [NH{sub 3}] and Aqueous ammonia [NH{sub 4}OH], both defined as poison gases by US authorities and most Western nations. Storage and handling procedures for these products are strictly regulated. Wilhelm Environmental Technologies Inc. is developing use of solid, formed or prilled Urea [CO(NH{sub 2}){sub 2}] as the feedstock. When heated in moist air, Urea sublimes to ammonia [NH{sub 3}] and carbon dioxide [CO{sub 2}]. Urea is stored and handled without restrictions or environmental concerns. Urea is a more expensive feedstock than NH{sub 3}, but much less expensive than [NH{sub 4}OH]. The design, and operating results, of a pilot system at Jacksonville Electric St. John's River Plant [Unit 2] are described. The pilot plant successfully sublimed Urea up to 100 pounds/hour. Further testing is planned. Very large ammonia use may favor NH{sub 3}, but smaller quantities can be produced at attractive prices with Urea based ammonia systems. Storage costs are far less. Many fluidized-bed boilers can use pastille or solid urea metered directly into the existing cyclones for NO{sub x} control. This is more economical than aqueous ammonia or aqueous urea based technology.

  7. Effect of dry-air chilling on sensory descriptive profiles of cooked broiler breast meat deboned four hours after the initiation of chilling.

    PubMed

    Zhuang, H; Savage, E M; Smith, D P; Berrang, M E

    2009-06-01

    The objective of this study was to evaluate the effect of a dry air-chilling (AC) method on sensory texture and flavor descriptive profiles of broiler pectoralis major (fillet) and pectoralis minor (tender). The profiles of the muscles immersion-chilled and deboned at the same postmortem time and the profiles of the muscles hot-boned (or no chill) were used for the comparison. A total of 108 eviscerated carcasses (6-wk-old broilers) were obtained from a commercial processing line before the chillers. Carcasses were transported to a laboratory facility where they were either i) chilled by a dry AC method (0.7 degrees C, 150 min in a cold room), ii) chilled by immersion chilling (IC; 0.3 degrees C, 50 min in a chiller), or iii) not chilled (9 birds per treatment per replication). Both IC and AC fillets and tenders were removed from the bone at 4 h after the initiation of chilling (approximately 4.75 h postmortem) in a processing area (18 degrees C). The no-chill muscles were removed immediately upon arrival. The sensory properties (21 attributes) of cooked broiler breast meat were evaluated by trained panelists using 0- to 15-point universal intensity scales. The average intensity scores of the 9 flavor attributes analyzed ranged from 0.9 to 4.0. Regardless of breast muscle type, there were no significant differences in sensory flavor descriptive profiles between the 3 treatments. The average intensity scores of the 12 texture attributes ranged from 1.5 to 7.5 and there were no significant differences between the AC and IC samples. The average intensity scores of the texture attributes, cohesiveness, hardness, cohesiveness of mass, rate of breakdown, and chewiness of the no chill fillets and tenders were significantly higher than those of either of the chilled samples. These results demonstrate that chicken breast meat from AC retains sensory flavor profile characteristics but AC results in sensory texture profile differences when compared with no-chill meat. Sensory

  8. From the Solution Processing of Hydrophilic Molecules to Polymer-Phthalocyanine Hybrid Materials for Ammonia Sensing in High Humidity Atmospheres

    PubMed Central

    Gaudillat, Pierre; Jurin, Florian; Lakard, Boris; Buron, Cédric; Suisse, Jean-Moïse; Bouvet, Marcel

    2014-01-01

    We have prepared different hybrid polymer-phthalocyanine materials by solution processing, starting from two sulfonated phthalocyanines, s-CoPc and CuTsPc, and polyvinylpyrrolidone (PVP), polyethylene glycol (PEG), poly(acrylic acid-co-acrylamide) (PAA-AM), poly(diallyldimethylammonium chloride) (PDDA) and polyaniline (PANI) as polymers. We also studied the response to ammonia (NH3) of resistors prepared from these sensing materials. The solvent casted films, prepared from s-CoPc and PVP, PEG and PAA-AM, were highly insulating and very sensitive to the relative humidity (RH) variation. The incorporation of s-CoPc in PDDA by means of layer-by-layer (LBL) technique allowed to stabilize the film, but was too insulating to be interesting. We also prepared PANI-CuTsPc hybrid films by LBL technique. It allowed a regular deposition as evidenced by the linear increase of the absorbance at 688 nm as a function of the number of bilayers. The sensitivity to ammonia (NH3) of PANi-CuTsPc resistors was very high compared to that of individual materials, giving up to 80% of current decrease when exposed to 30 ppm NH3. Contrarily to what happens with neutral polymers, in PANI, CuTsPc was stabilized by strong electrostatic interactions, leading to a stable response to NH3, whatever the relative humidity in the range 10%–70%. Thus, the synergy of PANI with ionic macrocycles used as counteranions combined with their simple aqueous solution processing opens the way to the development of new gas sensors capable of operating in real world conditions. PMID:25061841

  9. Atmospheric dispersion of ammonia: an ammonia fog model

    SciTech Connect

    Kansa, E.J.; Ermak, D.L.

    1983-01-01

    Ammonia (NH/sub 3/), a by-product of many chemical processes, is widely used as a fertilizer and as a raw material for many chemical syntheses. The purpose of this paper is to discuss the atmospheric dispersion of ammonia resulting from a high pressure release. The resulting nature of the two-phase cloud of ammonia vapor and droplets has a significant effect on its dispersion characteristics. Our calculations of a 40 ton release show that even under moderately high wind conditions, the resulting ammonia cloud remains negatively buoyant for considerable distances downwind.

  10. Atmospheric dispersion of ammonia: an ammonia fog model

    SciTech Connect

    Kansa, E.J.; Ermak,D.L.

    1983-04-01

    Ammonia (NH/sub 3/), a by-product of many chemical processes, is widely used as a fertilizer and as a raw material for many chemical syntheses. The purpose of this paper is to discuss the atmospheric dispersion of ammonia resulting from a high pressure release. The resulting nature of the two-phase clouds of ammonia vapor and droplets has a significant effect on its dispersion characteristics. Our calculations of a 40 ton release show that even under moderately high wind conditions, the resulting ammonia cloud remains negatively buoyant for considerable distances downwind.

  11. Atmospheric dispersion of ammonia: an ammonia fog model

    SciTech Connect

    Kansa, E.J.; Ermak, D.L.; Chan, S.T.; Rodean, H.C.

    1983-07-01

    Ammonia (NH/sub 3/), a by-product of many chemical processes, is widely used as a fertilizer and as a raw material for many chemical syntheses. The purpose of this paper is to discuss the atmospheric dispersion of ammonia resulting from a high pressure release. The resulting nature of the two-phase cloud of ammonia vapor and droplets has a significant effect on its dispersion characteristics. Our calculations of a 40 ton release show that even under moderately high wind conditions, the resulting ammonia cloud remains negatively buoyant for considerable distances downwind. 10 references, 15 figures.

  12. Molecular basis of chill resistance adaptations in poikilothermic animals.

    PubMed

    Hayward, Scott A L; Manso, Bruno; Cossins, Andrew R

    2014-01-01

    Chill and freeze represent very different components of low temperature stress. Whilst the principal mechanisms of tissue damage and of acquired protection from freeze-induced effects are reasonably well established, those for chill damage and protection are not. Non-freeze cold exposure (i.e. chill) can lead to serious disruption to normal life processes, including disruption to energy metabolism, loss of membrane perm-selectivity and collapse of ion gradients, as well as loss of neuromuscular coordination. If the primary lesions are not relieved then the progressive functional debilitation can lead to death. Thus, identifying the underpinning molecular lesions can point to the means of building resistance to subsequent chill exposures. Researchers have focused on four specific lesions: (i) failure of neuromuscular coordination, (ii) perturbation of bio-membrane structure and adaptations due to altered lipid composition, (iii) protein unfolding, which might be mitigated by the induced expression of compatible osmolytes acting as 'chemical chaperones', (iv) or the induced expression of protein chaperones along with the suppression of general protein synthesis. Progress in all these potential mechanisms has been ongoing but not substantial, due in part to an over-reliance on straightforward correlative approaches. Also, few studies have intervened by adoption of single gene ablation, which provides much more direct and compelling evidence for the role of specific genes, and thus processes, in adaptive phenotypes. Another difficulty is the existence of multiple mechanisms, which often act together, thus resulting in compensatory responses to gene manipulations, which may potentially mask disruptive effects on the chill tolerance phenotype. Consequently, there is little direct evidence of the underpinning regulatory mechanisms leading to induced resistance to chill injury. Here, we review recent advances mainly in lower vertebrates and in arthropods, but increasingly

  13. Engineering Design and Operation Report: Biological Treatment Process for the Removal of Ammonia from a Small Drinking Water System in Iowa: Pilot to Full-Scale

    EPA Science Inventory

    Many regions in the United States have excessive levels of ammonia in their drinking water sources (e.g., ground and surface waters) as a result of naturally occurring processes, agricultural and urban runoff, concentrated animal feeding operations, municipal wastewater treatment...

  14. Summary Report: Pilot Study of an Innovative Biological Treatment Process for the Removal of Ammonia from a Small Drinking Water System

    EPA Science Inventory

    The use of biologically active filtration to oxidize ammonia as a full-scale drinking water treatment process has not been thoroughly considered in the United States. A number of concerns with biological water treatment exist including the potential release of excessive numbers o...

  15. Cooling of Poultry Using Immersion or air chilling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During processing, poultry carcasses must be cooled to 40 F or below within 4 to 8 hours after slaughter to retard growth of pathogenic and spoilage microorganisms. In the U.S., poultry has traditionally been cooled using immersion chilling because this method is both economical and efficient; howe...

  16. Interaction of chill and heat in peach flower bud dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peach bud dormancy requirement is a critical factor in selecting adapted cultivars, but the dormancy process is not well-understood. The Utah model proposes bloom occurs after a cultivar-specific amount of chilling followed by 5000 heat units above 4 °C. This model works well in colder climates, but...

  17. Membrane-Based Gas Traps for Ammonia, Freon-21, and Water Systems to Simplify Ground Processing

    NASA Technical Reports Server (NTRS)

    Ritchie, Stephen M. C.

    2003-01-01

    is when particles adhere to the hydrophobic membrane, promoting formation of a water layer about it that can blind the membrane for gas transport (Figure 1). This mechanism is the most probable cause for observed failures with the existing design. The objective of this project was to devise a strategy for choosing new membrane materials (database development and procedure), redesign of the gas trap to mitigate blinding effects, and to develop a design that can be used in ammonia and Freon-21 coolant loops.

  18. Chilling acclimation provides immunity to stress by altering regulatory networks and inducing genes with protective functions in Cassava

    PubMed Central

    2014-01-01

    Background Stress acclimation is an effective mechanism that plants acquired for adaption to dynamic environment. Even though generally considered to be sensitive to low temperature, Cassava, a major tropical crop, can be tolerant to much lower temperature after chilling acclimation. Improvement to chilling resistance could be beneficial to breeding. However, the underlying mechanism and the effects of chilling acclimation on chilling tolerance remain largely unexplored. Results In order to understand the mechanism of chilling acclimation, we profiled and analyzed the transcriptome and microRNAome of Cassava, using high-throughput deep sequencing, across the normal condition, a moderate chilling stress (14°C), a harsh stress (4°C) after chilling acclimation (14°C), and a chilling shock from 24°C to 4°C. The results revealed that moderate stress and chilling shock triggered comparable degrees of transcriptional perturbation, and more importantly, about two thirds of differentially expressed genes reversed their expression from up-regulation to down-regulation or vice versa in response to hash stress after experiencing moderate stress. In addition, microRNAs played important roles in the process of this massive genetic circuitry rewiring. Furthermore, function analysis revealed that chilling acclimation helped the plant develop immunity to further harsh stress by exclusively inducing genes with function for nutrient reservation therefore providing protection, whereas chilling shock induced genes with function for viral reproduction therefore causing damage. Conclusions Our study revealed, for the first time, the molecular basis of chilling acclimation, and showed potential regulation role of microRNA in chilling response and acclimation in Euphorbia. PMID:25090992

  19. A low-temperature process for the denitration of Hanford single-shell tank, nitrate-based waste utilizing the nitrate to ammonia and ceramic (NAC) process

    SciTech Connect

    Mattus, A.J.; Lee, D.D.; Dillow, T.A.; Farr, L.L.; Loghry, S.L.; Pitt, W.W.; Gibson, M.R.

    1994-12-01

    Bench-top feasibility studies with Hanford single-shell tank (SST) simulants, using a new, low-temperature (50 to 60C) process for converting nitrate to ammonia and ceramic (NAC), have conclusively shown that between 85 to 99% of the nitrate can be readily converted. In this process, aluminum powders or shot can be used to convert alkaline, nitrate-based supernate to ammonia and an aluminum oxide-sodium aluminate-based solid which might function as its own waste form. The process may actually be able to utilize already contaminated aluminum scrap metal from various DOE sites to effect the conversion. The final, nearly nitrate-free ceramic-like product can be pressed and sintered like other ceramics. Based upon the starting volumes of 6.2 and 3.1 M sodium nitrate solution, volume reductions of 50 to 55% were obtained for the waste form produced, compared to an expected 35 to 50% volume increase if the Hanford supernate were grouted. Engineering data extracted from bench-top studies indicate that the process will be very economical to operate, and data were used to cost a batch, 1,200-kg NO{sub 3}/h plant for working off Hanford SST waste over 20 years. Their total process cost analysis presented in the appendix, indicates that between $2.01 to 2.66 per kilogram of nitrate converted will be required. Additionally, data on the fate of select radioelements present in solution are presented in this report as well as kinetic, operational, and control data for a number of experiments. Additionally, if the ceramic product functions as its own waste form, it too will offer other cost savings associated with having a smaller volume of waste form as well as eliminating other process steps such as grouting.

  20. Ammonia Test

    MedlinePlus

    ... be ordered, along with other tests such as glucose , electrolytes , and kidney and liver function tests , to help diagnose the cause of ... Pages tab.) An increased ammonia level and decreased glucose ... may indicate that severe liver or kidney damage has impacted the body's ability ...

  1. Broiler carcass bacterial counts after immersion chilling using either a low or high volume of water.

    PubMed

    Northcutt, J K; Cason, J A; Smith, D P; Buhr, R J; Fletcher, D L

    2006-10-01

    A study was conducted to investigate the bacteriological impact of using different volumes of water during immersion chilling of broiler carcasses. Market-aged broilers were processed, and carcasses were cut into left and right halves along the keel bone immediately after the final bird wash. One half of each carcass pair was individually chilled at 4 degrees C in a separate bag containing either 2.1 L/kg (low) or 16.8 L/kg (high) of distilled water. Carcass halves were submersed in a secondary chill tank containing approximately 150 L of an ice-water mix (0.6 degrees C). After chilling for 45 min, carcass halves were rinsed with 100 mL of sterile water for 1 min. Rinses and chill water were analyzed for total aerobic bacteria (APC), Escherichia coli, Enterobacteriaceae, and Campylobacter. After chilling with a low volume of water, counts were 3.7, 2.5, 2.6, and 2.1 log(10) cfu/mL of rinse for APC, E. coli, Enterobacteriaceae, and Campylobacter, respectively. When a high volume of chill water was used, counts were 3.2, 1.7, 1.6, and 1.8 log(10) cfu/mL of rinse for APC, E. coli, Enterobacteriaceae, and Campylobacter, respectively. There was no difference in bacterial counts per milliliter of chill water among treatments. These results show that using additional water during immersion chilling of inoculated broilers will remove more bacteria from the carcass surfaces, but numbers of bacteria per milliliter in the chiller water will remain constant. The bacteriological impact of using more water during commercial immersion chilling may not be enough to offset economic costs. PMID:17012173

  2. [Emissions of greenhouse gas and ammonia from the full process of sewage sludge composting and land application of compost].

    PubMed

    Zhong, Jia; Wei, Yuan-Song; Zhao, Zhen-Feng; Ying, Mei-Juan; Zhou, Guo-Sheng; Xiong, Jian-Jun; Liu, Pei-Cai; Ge, Zhen; Ding, Gang-Qiang

    2013-11-01

    There is a great uncertainty of greenhouse gas (GHG) reduction and nitrogen conservation from the full process of sludge composting and land application of compost in China due to the lack of emission data of GHG such as N2O and CH4 and ammonia (NH3). The purpose of this study is to get emission characteristics of GHGs and NH3 from the full process with on-site observation. Results showed that the total GHG emission factor from full process of the turning windrow (TW) system (eCO2/dry sludge, 196.21 kg x t(-1)) was 1.61 times higher of that from the ATP system. Among the full process, N2O was mostly from the land application of compost, whereas CH4 mainly resulted from the sludge composting. In the sludge composting of ATP, the GHG emission equivalence of the ATP (eCO2/dry sludge, 12.47 kg x t(-1) was much lower than that of the TW (eCO2/dry sludge, 86.84 kg x t(-1)). The total NH3 emission factor of the TW (NH3/dry sludge, 6.86 kg x t(-1)) was slightly higher than that of the ATP (NH3/dry sludge, 6.63 kg x t(-1)). NH3 was the major contributor of nitrogen loss in the full process. During the composting, the nitrogen loss as NH3 from both TW and ATP was nearly the same as 30% of TN loss from raw materials, and the N and C loss caused by N2O and CH4 were negligible. These results clearly showed that the ATP was a kind of environmentally friendly composting technology. PMID:24455923

  3. Development of hyperspectral imaging technique for the detection of chilling injury in cucumbers

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Chen, Yud-Ren; Wang, C. Y.; Chan, D. E.; Kim, Moon S.

    2004-11-01

    Hyperspectral images of cucumbers were acquired before and during cold storage treatments as well as during subsequent room temperature (RT) storage to explore the potential for the detection of chilling induced damage in whole cucumbers. Region of interest (ROI) spectral features of chilling injured areas, resulting from cold storage treatments at 0°C or 5°C, showed a reduction in reflectance intensity during multi-day post chilling periods of RT storage. Large spectral differences between good-smooth skins and chilling injured skins occurred in the 700-850 nm visible/NIR region. A number of data processing methods, including simple spectral band algorithms, second difference, and principal component analysis (PCA), were attempted to discriminate the ROI spectra of good cucumber skins from those of chilling injured skins. Results revealed that using either a dual-band ratio algorithm (Q811/756) or a PCA model from a narrow spectral region of 733-848 nm could detect chilling injured skins with a success rate of over 90%. Furthermore, the dual-band algorithm was applied to the analysis of images of cucumbers at different conditions, and the resultant images showed more correct identification of chilling injured spots than other processing methods.

  4. Novel process of bio-chemical ammonia removal from air streams using a water reflux system and zeolite as filter media.

    PubMed

    Vitzthum von Eckstaedt, Sebastian; Charles, Wipa; Ho, Goen; Cord-Ruwisch, Ralf

    2016-02-01

    A novel biofilter that removes ammonia from air streams and converts it to nitrogen gas has been developed and operated continuously for 300 days. The ammonia from the incoming up-flow air stream is first absorbed into water and the carrier material, zeolite. A continuous gravity reflux of condensed water from the exit of the biofilter provides moisture for nitrifying bacteria to develop and convert dissolved ammonia (ammonium) to nitrite/nitrate. The down-flow of the condensed water reflux washes down nitrite/nitrate preventing ammonium and nitrite/nitrate accumulation at the top region of the biofilter. The evaporation caused by the inflow air leads to the accumulation of nitrite to extremely high concentrations in the bottom of the biofilter. The high nitrite concentrations favour the spontaneous chemical oxidation of ammonium by nitrite to nitrogen (N2). Tests showed that this chemical reaction was catalysed by the zeolite filter medium and allowed it to take place at room temperature. This study shows that ammonia can be removed from air streams and converted to N2 in a fully aerated single step biofilter. The process also overcomes the problem of microorganism-inhibition and resulted in zero leachate production. PMID:26363328

  5. Acidification of In-Storage-Psychrophilic-Anaerobic-Digestion (ISPAD) process to reduce ammonia volatilization: Model development and validation.

    PubMed

    Madani-Hosseini, Mahsa; Mulligan, Catherine N; Barrington, Suzelle

    2016-06-01

    In-Storage-Psychrophilic-Anaerobic-Digestion (ISPAD) is an ambient temperature treatment system for wastewaters stored for over 100days under temperate climates, which produces a nitrogen rich digestate susceptible to ammonia (NH3) volatilization. Present acidification techniques reducing NH3 volatilization are not only expensive and with secondary environmental effects, but do not apply to ISPAD relying on batch-to-batch inoculation. The objectives of this study were to identify and validate sequential organic loading (OL) strategies producing imbalances in acidogen and methanogen growth, acidifying ISPAD content one week before emptying to a pH of 6, while also preserving the inoculation potential. This acidification process is challenging as wastewaters often offer a high buffering capacity and ISPAD operational practices foster low microbial populations. A model simulating the ISPAD pH regime was used to optimize 3 different sequential OLs to decrease the ISPAD pH to 6.0. All 3 strategies were compared in terms of biogas production, volatile fatty acid (VFA) concentration, microbial activity, glucose consumption, and pH decrease. Laboratory validation of the model outputs confirmed that a sequential OL of 13kg glucose/m(3) of ISPAD content over 4days could indeed reduce the pH to 6.0. Such OL competes feasibly with present acidification techniques. Nevertheless, more research is required to explain the 3-day lag between the model results and the experimental data. PMID:27060886

  6. 21 CFR 890.5940 - Chilling unit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Chilling unit. 890.5940 Section 890.5940 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5940 Chilling unit....

  7. 21 CFR 890.5940 - Chilling unit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Chilling unit. 890.5940 Section 890.5940 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5940 Chilling unit....

  8. 21 CFR 890.5940 - Chilling unit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Chilling unit. 890.5940 Section 890.5940 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5940 Chilling unit....

  9. 21 CFR 890.5940 - Chilling unit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Chilling unit. 890.5940 Section 890.5940 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5940 Chilling unit....

  10. 21 CFR 890.5940 - Chilling unit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Chilling unit. 890.5940 Section 890.5940 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5940 Chilling unit....

  11. Renal Ammonia Metabolism and Transport

    PubMed Central

    Weiner, I. David; Verlander, Jill W.

    2015-01-01

    Renal ammonia metabolism and transport mediates a central role in acid-base homeostasis. In contrast to most renal solutes, the majority of renal ammonia excretion derives from intrarenal production, not from glomerular filtration. Renal ammoniagenesis predominantly results from glutamine metabolism, which produces 2 NH4+ and 2 HCO3− for each glutamine metabolized. The proximal tubule is the primary site for ammoniagenesis, but there is evidence for ammoniagenesis by most renal epithelial cells. Ammonia produced in the kidney is either excreted into the urine or returned to the systemic circulation through the renal veins. Ammonia excreted in the urine promotes acid excretion; ammonia returned to the systemic circulation is metabolized in the liver in a HCO3−-consuming process, resulting in no net benefit to acid-base homeostasis. Highly regulated ammonia transport by renal epithelial cells determines the proportion of ammonia excreted in the urine versus returned to the systemic circulation. The traditional paradigm of ammonia transport involving passive NH3 diffusion, protonation in the lumen and NH4+ trapping due to an inability to cross plasma membranes is being replaced by the recognition of limited plasma membrane NH3 permeability in combination with the presence of specific NH3-transporting and NH4+-transporting proteins in specific renal epithelial cells. Ammonia production and transport are regulated by a variety of factors, including extracellular pH and K+, and by several hormones, such as mineralocorticoids, glucocorticoids and angiotensin II. This coordinated process of regulated ammonia production and transport is critical for the effective maintenance of acid-base homeostasis. PMID:23720285

  12. Process-based Modeling of Ammonia Emission from Beef Cattle Feedyards with the Integrated Farm Systems Model.

    PubMed

    Waldrip, Heidi M; Rotz, C Alan; Hafner, Sasha D; Todd, Richard W; Cole, N Andy

    2014-07-01

    Ammonia (NH) volatilization from manure in beef cattle feedyards results in loss of agronomically important nitrogen (N) and potentially leads to overfertilization and acidification of aquatic and terrestrial ecosystems. In addition, NH is involved in the formation of atmospheric fine particulate matter (PM), which can affect human health. Process-based models have been developed to estimate NH emissions from various livestock production systems; however, little work has been conducted to assess their accuracy for large, open-lot beef cattle feedyards. This work describes the extension of an existing process-based model, the Integrated Farm Systems Model (IFSM), to include simulation of N dynamics in this type of system. To evaluate the model, IFSM-simulated daily per capita NH emission rates were compared with emissions data collected from two commercial feedyards in the Texas High Plains from 2007 to 2009. Model predictions were in good agreement with observations and were sensitive to variations in air temperature and dietary crude protein concentration. Predicted mean daily NH emission rates for the two feedyards had 71 to 81% agreement with observations. In addition, IFSM estimates of annual feedyard emissions were within 11 to 24% of observations, whereas a constant emission factor currently in use by the USEPA underestimated feedyard emissions by as much as 79%. The results from this study indicate that IFSM can quantify average feedyard NH emissions, assist with emissions reporting, provide accurate information for legislators and policymakers, investigate methods to mitigate NH losses, and evaluate the effects of specific management practices on farm nutrient balances. PMID:25603064

  13. Processes of ammonia air-surface exchange in a fertilized Zea mays canopy

    NASA Astrophysics Data System (ADS)

    Walker, J. T.; Jones, M. R.; Bash, J. O.; Myles, L.; Meyers, T.; Schwede, D.; Herrick, J.; Nemitz, E.; Robarge, W.

    2013-02-01

    Recent incorporation of coupled soil biogeochemical and bi-directional NH3 air-surface exchange algorithms into regional air quality models holds promise for further reducing uncertainty in estimates of NH3 emissions from fertilized soils. While this represents a significant advancement over previous approaches, the evaluation and improvement of such modeling systems for fertilized crops requires process-level field measurements over extended periods of time that capture the range of soil, vegetation, and atmospheric conditions that drive short-term (i.e., post-fertilization) and total growing season NH3 fluxes. This study examines the processes of NH3 air-surface exchange in a fertilized corn (Zea mays) canopy over the majority of a growing season to characterize soil emissions after fertilization and investigate soil-canopy interactions. Micrometeorological flux measurements above the canopy, measurements of soil, leaf apoplast and dew/guttation chemistry, and a combination of in-canopy measurements, inverse source/sink, and resistance modeling were employed. Over a period of approximately 10 weeks following fertilization, daily mean and median net canopy-scale fluxes yielded cumulative total N losses of 8.4% and 6.1%, respectively, of the 134 kg N ha-1 surface applied to the soil as urea ammonium nitrate (UAN). During the first month after fertilization, daily mean emission fluxes were positively correlated with soil temperature and soil volumetric water. Diurnally, maximum hourly average fluxes of ≈ 700 ng N m-2 s-1 occurred near mid-day, coincident with the daily maximum in friction velocity. Net emission was still observed 5 to 10 weeks after fertilization, although mid-day peak fluxes had declined to ≈ 125 ng N m-2 s-1. A key finding of the surface chemistry measurements was the observation of high pH (7.0-8.5) in leaf dew/guttation, which reduced the ability of the canopy to recapture soil emissions during wet periods. In-canopy measurements near peak

  14. Processes of ammonia air-surface exchange in a fertilized Zea mays canopy

    NASA Astrophysics Data System (ADS)

    Walker, J. T.; Jones, M. R.; Bash, J. O.; Myles, L.; Meyers, T.; Schwede, D.; Herrick, J.; Nemitz, E.; Robarge, W.

    2012-06-01

    Recent incorporation of coupled soil biogeochemical and bi-directional NH3 air-surface exchange algorithms into regional air quality models holds promise for further reducing uncertainty in estimates of NH3 emissions from fertilized soils. While this represents a significant advancement over previous approaches, the evaluation and improvement of such modeling systems for fertilized crops requires process level field measurements over extended periods of time that capture the range of soil, vegetation, and atmospheric conditions that drive short term (i.e., post fertilization) and total growing seasonNH3 fluxes. This study examines the processes of NH3 air-surface exchange in a fertilized corn (Zea mays) canopy over the majority of a growing season to characterize soil emissions after fertilization and investigate soil-canopy interactions. Micrometeorological flux measurements above the canopy, measurements of soil, leaf apoplast and dew/guttation chemistry, and a combination of in-canopy measurements, inverse source/sink, and resistance modeling were employed. Over a period of approximately 10 weeks following fertilization, daily mean and median net canopy-scale fluxes yielded cumulative total N losses of 8.4% and 6.1%, respectively, of the 134 kg N ha-1 surface applied to the soil as urea ammonium nitrate (UAN). During the first month after fertilization, daily mean emission fluxes were positively correlated with soil temperature and soil volumetric water. Diurnally, maximum hourly average fluxes of ≈700 ng N m-2 s-1 occurred near mid-day, coincident with the daily maximum in friction velocity. Net emission was still observed 5 to 10 weeks after fertilization, although mid-day peak fluxes had declined to ≈125 ng N m-2 s-1 A key finding of the surface chemistry measurements was the observation of high pH (7.0 - 8.5) in leaf dew/guttation, which reduced the ability of the canopy to recapture soil emissions during wet periods. In-canopy measurements near peak LAI

  15. Prevalence of Salmonella Following Immersion Chilling for Matched Neck Skin, Whole Carcass Rinse, and Whole Carcass Enrichment Sampling Methodologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella prevalence and the serogroups recovered following immersion chilling were determined for matched enriched neck skin, whole carcass rinse, and whole carcass samples. Commercially processed and eviscerated broiler carcasses were chilled in ice/tap water 40 min with or without 20 ppm free c...

  16. Novel Regenerated Solvent Extraction Processes for the Recovery of Carboxylic Acids or Ammonia from Aqueous Solutions Part I. Regeneration of Amine-Carboxylic Acid Extracts

    SciTech Connect

    Poole, L.J.; King, C.J.

    1990-03-01

    Two novel regenerated solvent extraction processes are examined. The first process has the potential to reduce the energy costs inherent in the recovery of low-volatility carboxylic acids from dilute aqueous solutions. The second process has the potential for reducing the energy costs required for separate recovery of ammonia and acid gases (e.g. CO{sub 2} and H{sub 2}S) from industrial sour waters. The recovery of carboxylic acids from dilute aqueous solution can be achieved by extraction with tertiary amines. An approach for regeneration and product recovery from such extracts is to back-extract the carboxylic acid with a water-soluble, volatile tertiary amine, such as trimethylamine. The resulting trimethylammonium carboxylate solution can be concentrated and thermally decomposed, yielding the product acid and the volatile amine for recycle. Experimental work was performed with lactic acid, succinic acid, and fumaric acid. Equilibrium data show near-stoichiometric recovery of the carboxylic acids from an organic solution of Alamine 336 into aqueous solutions of trimethylamine. For fumaric and succinic acids, partial evaporation of the aqueous back extract decomposes the carboxylate and yields the acid product in crystalline form. The decomposition of aqueous solutions of trimethylammonium lactates was not carried out to completion, due to the high water solubility of lactic acid and the tendency of the acid to self-associate. The separate recovery of ammonia and acid gases from sour waters can be achieved by combining steam-stripping of the acid gases with simultaneous removal of ammonia by extraction with a liquid cation exchanger. The use of di-2,4,4-trimethylpentyl phosphinic acid as the liquid cation exchanger is explored in this work. Batch extraction experiments were carried out to measure the equilibrium distribution ratio of ammonia between an aqueous buffer solution and an organic solution of the phosphinic acid (0.2N) in Norpar 12. The concentration

  17. Chilling and frost tolerance in Miscanthus and Saccharum genotypes bred for cool temperate climates

    PubMed Central

    Friesen, Patrick C.; Peixoto, Murilo M.; Busch, Florian A.; Johnson, Daniel C.; Sage, Rowan F.

    2014-01-01

    Miscanthus hybrids are leading candidates for bioenergy feedstocks in mid to high latitudes of North America and Eurasia, due to high productivity associated with the C4 photosynthetic pathway and their tolerance of cooler conditions. However, as C4 plants, they may lack tolerance of chilling conditions (0–10 °C) and frost, particularly when compared with candidate C3 crops at high latitudes. In higher latitudes, cold tolerance is particularly important if the feedstock is to utilize fully the long, early-season days of May and June. Here, leaf gas exchange and fluorescence are used to assess chilling tolerance of photosynthesis in five Miscanthus hybrids bred for cold tolerance, a complex Saccharum hybrid (energycane), and an upland sugarcane variety with some chilling tolerance. The chilling treatment consisted of transferring warm-grown plants (25/20 °C day/night growth temperatures) to chilling (12/5 °C) conditions for 1 week, followed by assessing recovery after return to warm temperatures. Chilling tolerance was also evaluated in outdoor, spring-grown Miscanthus genotypes before and after a cold front that was punctuated by a frost event. Miscanthus×giganteus was found to be the most chilling-tolerant genotype based on its ability to maintain a high net CO2 assimilation rate (A) during chilling, and recover A to a greater degree following a return to warm conditions. This was associated with increasing its capacity for short-term dark-reversible photoprotective processes (ΦREG) and the proportion of open photosystem II reaction centres (qL) while minimizing photoinactivation (ΦNF). Similarly, in the field, M.×giganteus exhibited a significantly greater A and pre-dawn F v/F m after the cold front compared with the other chilling-sensitive Miscanthus hybrids. PMID:24642848

  18. Chilling and frost tolerance in Miscanthus and Saccharum genotypes bred for cool temperate climates.

    PubMed

    Friesen, Patrick C; Peixoto, Murilo M; Busch, Florian A; Johnson, Daniel C; Sage, Rowan F

    2014-07-01

    Miscanthus hybrids are leading candidates for bioenergy feedstocks in mid to high latitudes of North America and Eurasia, due to high productivity associated with the C4 photosynthetic pathway and their tolerance of cooler conditions. However, as C4 plants, they may lack tolerance of chilling conditions (0-10 °C) and frost, particularly when compared with candidate C3 crops at high latitudes. In higher latitudes, cold tolerance is particularly important if the feedstock is to utilize fully the long, early-season days of May and June. Here, leaf gas exchange and fluorescence are used to assess chilling tolerance of photosynthesis in five Miscanthus hybrids bred for cold tolerance, a complex Saccharum hybrid (energycane), and an upland sugarcane variety with some chilling tolerance. The chilling treatment consisted of transferring warm-grown plants (25/20 °C day/night growth temperatures) to chilling (12/5 °C) conditions for 1 week, followed by assessing recovery after return to warm temperatures. Chilling tolerance was also evaluated in outdoor, spring-grown Miscanthus genotypes before and after a cold front that was punctuated by a frost event. Miscanthus×giganteus was found to be the most chilling-tolerant genotype based on its ability to maintain a high net CO2 assimilation rate (A) during chilling, and recover A to a greater degree following a return to warm conditions. This was associated with increasing its capacity for short-term dark-reversible photoprotective processes (ΦREG) and the proportion of open photosystem II reaction centres (qL) while minimizing photoinactivation (ΦNF). Similarly, in the field, M.×giganteus exhibited a significantly greater A and pre-dawn F v/F m after the cold front compared with the other chilling-sensitive Miscanthus hybrids. PMID:24642848

  19. Salicylic acid and methyl jasmonate improve chilling tolerance in cold-stored lemon fruit (Citrus limon).

    PubMed

    Siboza, Xolani Irvin; Bertling, Isa; Odindo, Alfred Oduor

    2014-11-15

    Chilling injury (CI) is associated with the degradation of membrane integrity which can be aligned to phenolic oxidation activated by polyphenol oxidase (PPO) and peroxidase (POD), enzymes responsible for tissue browning. Phenylalanine ammonia-lyase (PAL) is a further enzyme prominent in the phenolic metabolism that is involved in acclimation against chilling stress. It was hypothesized that treatment with methyl jasmonate (MJ) and salicylic acid (SA) may enhance chilling tolerance in lemon fruit by increasing the synthesis of total phenolics and PAL by activating the key enzyme regulating the shikimic acid pathway whilst inhibiting the activity of POD and PPO. Lemon fruit were treated with 10μM MJ, 2mM SA or 10μM MJ plus 2mM SA, waxed, stored at -0.5, 2 or 4.5°C for up to 28 days plus 7 days at 23°C. Membrane integrity was studied by investigating membrane permeability and the degree of membrane lipid peroxidation in lemon flavedo following cold storage. The 10μM MJ plus 2mM SA treatment was most effective in enhancing chilling tolerance of lemon fruit, significantly reducing chilling-induced membrane permeability and membrane lipid peroxidation of lemon flavedo tissue. This treatment also increased total phenolics and PAL activity in such tissue while inhibiting POD activity, the latter possibly contributing to the delay of CI manifestation. PPO activity was found to be a poor biochemical marker of CI. Treatment with 10μM MJ plus 2mM SA resulted in an alteration of the phenolic metabolism, enhancing chilling tolerance, possibly through increased production of total phenolics and the activation of PAL and inhibition of POD. PMID:25216124

  20. Manure-DNDC: a biogeochemical process model for quantifying greenhouse gas and ammonia emissions from livestock manure systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    From the point of view of biogeochemistry, manure is a complex of organic matter containing minor minerals. When manure is excreted by animals, it undergoes a series of reactions such as decomposition, hydrolysis, ammonia volatilization, nitrification, denitrification, and fermentation from which ca...

  1. Process-based modeling of ammonia emission from beef cattle feedyards with the integrated farm systems model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia volatilization from manure in beef cattle feedyards results in loss of agronomically important nitrogen (N), and potentially leads to over-fertilization and acidification of aquatic and terrestrial ecosystems and formation of atmospheric fine particulate matter that can impact human health. ...

  2. Effect of 24-epibrassinolide treatment on the metabolism of eggplant fruits in relation to development of pulp browning under chilling stress.

    PubMed

    Gao, Hui; Kang, LiNa; Liu, Qing; Cheng, Ni; Wang, BiNi; Cao, Wei

    2015-06-01

    This study aims to investigate the effect of 24-epibrassinolide (EBR) on the metabolism in relation to development of chilling injury-induced pulp browning of eggplant fruit. The fruits were dipped for 10 min in solutions containing 10 μmM EBR and then stored at 1 °C for 15 days. Chilling injury index, weight loss, electrolyte leakage and malondialdehyde (MDA) content of control fruit increased during storage. Chilling injury improved phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), and peroxidase (POD) activities, which are correlated with the increase of total phenolic content and pulp browning of eggplant fruit. The inhibition of pulp browning by EBR treatment was possibly attributed to preserving the cell membrane integrity, reducing total phenolic content, and decreasing PAL, PPO, and POD activities. These results suggest that EBR may inhibit chilling injury and pulp browning in eggplant fruit during cold storage. PMID:26028720

  3. Mutagenic activity at different stages of an industrial ammonia caramel process detected in Salmonella typhimurium TA100 following pre-incubation.

    PubMed

    Jensen, N J; Willumsen, D; Knudsen, I

    1983-10-01

    Mutagenic activity of a commercial ammonia caramel colouring was demonstrated in Salmonella typhimurium TA100 without metabolic activation. The activity in strain TA100 was increased using a 10-min pre-incubation, and a clear dose-response relationship was seen using this method. Investigation of samples taken from the different stages in the industrial process showed a constant level of mutagenic activity in samples from the middle to the end of the heating process with a steep increase in the sample taken after the end of heating. No mutagenic activity was seen in assays with S. typhimurium strains TA1535 and TA98. PMID:6360827

  4. Phosphatidylglycerol and Chilling Sensitivity in Plants

    PubMed Central

    Roughan, P. Grattan

    1985-01-01

    The hypothesis that molecular species of thylakoid phosphatidylglycerol containing two saturated fatty acids (disaturated phosphatidylglycerol) confer chilling sensitivity upon plants was tested by analyzing the fatty acid composition of phosphatidylglycerols isolated from leaves of a range of plants expected to have different sensitivities to chilling temperatures. `Saturated' fatty acids (palmitate plus stearate plus hexadeca-trans-3-enoate) as a proportion of total phosphatidylglycerol fatty acids varied from 51 to 80 mole per cent in the plants analyzed but appeared to be rigidly fixed for a given plant species, being unaffected by leaf maturity or by environment. Hexadeca-trans-3-enoate occurred only at the sn-2 position, whereas C-18 fatty acids occurred only at the sn-1 position of thylakoid phosphatidylglycerol. Therefore, the proportion of disaturated molecular species could be predicted accurately from the total fatty acids of phosphatidylglycerol. Disaturated molecular species accounted for <25% of the total phosphatidylglycerol from leaves of chilling-resistant plants and for 50 to 60% of the phosphatidylglycerol in leaves from some of the most chilling-sensitive plants. However, not all chilling-sensitive plants contained high proportions of disaturated phosphatidylglycerol; solanaceous and other 16:3-plants and C4 grasses may be important exceptions. Nonetheless, proportions of disaturated phosphatidylglycerol increased concomitantly with increasing chilling sensitivity of plants within a genus. PMID:16664127

  5. Suppression of volatile production in tomato fruit exposed to chilling temperature and alleviation of chilling injury by a pre-chilling heat treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chilling exposure of tomatoes to 5°C for longer than 6-8 days can cause surface pitting, irregular (blotchy) color development and other symptoms of chilling injury (CI). The objectives for this study were to investigate whether a 4-day exposure of tomato fruit to chilling at the mature green stage ...

  6. Suppression of volatile production in tomato fruit exposed to chilling temperature and alleviation of chilling injury by a pre-chilling heat treatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chilling exposure of tomato fruit to 5 °C for less than 5 days at mature green stage does not cause visual symptom of chilling injury (CI), however, it is unknown whether such conditions would impact flavor quality (internal CI) after ripening, and if a pre-chilling heat treatment could alleviate in...

  7. Microbiological evaluation of chicken carcasses in an immersion chilling system with water renewal at 8 and 16 hours.

    PubMed

    Souza, L C T; Pereira, J G; Spina, T L B; Izidoro, T B; Oliveira, A C; Pinto, J P A N

    2012-05-01

    Since 2004, Brazil has been the leading exporter of chicken. Because of the importance of this sector in the Brazilian economy, food safety must be ensured by control and monitoring of the production stages susceptible to contamination, such as the chilling process. The goal of this study was to evaluate changes in microbial levels on chicken carcasses and in chilling water after immersion in a chilling system for 8 and 16 h during commercial processing. An objective of the study was to encourage discussion regarding the Brazilian Ministry of Agriculture Livestock and Food Supply regulation that requires chicken processors to completely empty, clean, and disinfect each tank of the chilling system after every 8-h shift. Before and after immersion chilling, carcasses were collected and analyzed for mesophilic bacteria, Enterobacteriaceae, coliforms, and Escherichia coli. Samples of water from the chilling system were also analyzed for residual free chlorine. The results do not support required emptying of the chiller tank after 8 h; these tanks could be emptied after 16 h. The results for all carcasses tested at the 8- and 16-h time points indicated no significant differences in the microbiological indicators evaluated. These data provide both technical and scientific support for discussing changes in federal law regarding the management of immersion chilling water systems used as part of the poultry processing line. PMID:22564950

  8. Abundance and diversity of ammonia-oxidizing archaea and bacteria on granular activated carbon and their fates during drinking water purification process.

    PubMed

    Niu, Jia; Kasuga, Ikuro; Kurisu, Futoshi; Furumai, Hiroaki; Shigeeda, Takaaki; Takahashi, Kazuhiko

    2016-01-01

    Ammonia is a precursor to trichloramine, which causes an undesirable chlorinous odor. Granular activated carbon (GAC) filtration is used to biologically oxidize ammonia during drinking water purification; however, little information is available regarding the abundance and diversity of ammonia-oxidizing archaea (AOA) and bacteria (AOB) associated with GAC. In addition, their sources and fates in water purification process remain unknown. In this study, six GAC samples were collected from five full-scale drinking water purification plants in Tokyo during summer and winter, and the abundance and community structure of AOA and AOB associated with GAC were studied in these two seasons. In summer, archaeal and bacterial amoA genes on GACs were present at 3.7 × 10(5)-3.9 × 10(8) gene copies/g-dry and 4.5 × 10(6)-4.2 × 10(8) gene copies/g-dry, respectively. In winter, archaeal amoA genes remained at the same level, while bacterial amoA genes decreased significantly for all GACs. No differences were observed in the community diversity of AOA and AOB from summer to winter. Phylogenetic analysis revealed high AOA diversity in group I.1a and group I.1b in raw water. Terminal-restriction fragment length polymorphism analysis of processed water samples revealed that AOA diversity decreased dramatically to only two OTUs in group I.1a after ozonation, which were identical to those detected on GAC. It suggests that ozonation plays an important role in determining AOA diversity on GAC. Further study on the cell-specific activity of AOA and AOB is necessary to understand their contributions to in situ nitrification performance. PMID:26463999

  9. Deep-sequencing transcriptome analysis of chilling tolerance mechanisms of a subnival alpine plant, Chorispora bungeana

    PubMed Central

    2012-01-01

    Background The plant tolerance mechanisms to low temperature have been studied extensively in the model plant Arabidopsis at the transcriptional level. However, few studies were carried out in plants with strong inherited cold tolerance. Chorispora bungeana is a subnival alpine plant possessing strong cold tolerance mechanisms. To get a deeper insight into its cold tolerance mechanisms, the transcriptome profiles of chilling-treated C. bungeana seedlings were analyzed by Illumina deep-sequencing and compared with Arabidopsis. Results Two cDNA libraries constructed from mRNAs of control and chilling-treated seedlings were sequenced by Illumina technology. A total of 54,870 unigenes were obtained by de novo assembly, and 3,484 chilling up-regulated and 4,571 down-regulated unigenes were identified. The expressions of 18 out of top 20 up-regulated unigenes were confirmed by qPCR analysis. Functional network analysis of the up-regulated genes revealed some common biological processes, including cold responses, and molecular functions in C. bungeana and Arabidopsis responding to chilling. Karrikins were found as new plant growth regulators involved in chilling responses of C. bungeana and Arabidopsis. However, genes involved in cold acclimation were enriched in chilling up-regulated genes in Arabidopsis but not in C. bungeana. In addition, although transcription activations were stimulated in both C. bungeana and Arabidopsis, no CBF putative ortholog was up-regulated in C. bungeana while CBF2 and CBF3 were chilling up-regulated in Arabidopsis. On the other hand, up-regulated genes related to protein phosphorylation and auto-ubiquitination processes were over-represented in C. bungeana but not in Arabidopsis. Conclusions We conducted the first deep-sequencing transcriptome profiling and chilling stress regulatory network analysis of C. bungeana, a subnival alpine plant with inherited cold tolerance. Comparative transcriptome analysis suggests that cold acclimation is not

  10. Semi-empirical process-based models for ammonia emissions from beef, swine, and poultry operations in the United States

    NASA Astrophysics Data System (ADS)

    McQuilling, Alyssa M.; Adams, Peter J.

    2015-11-01

    Farm-level ammonia emissions factors in the literature vary by an order of magnitude due to variations in manure management practices and meteorology, and it is essential to capture this variability in emission inventories used for atmospheric modeling. Loss of ammonia to the atmosphere is modeled here through a nitrogen mass balance with losses controlled by mass transfer resistance parameters, which vary with meteorological conditions and are tuned to match literature-reported emissions factors. Variations due to management practices are captured by having tuned parameters that are specific to each set of management practices. The resulting farm emissions models (FEMs) explain between 20% and 70% of the variability in published emissions factors and typically estimate emission factors within a factor of 2. The r2 values are: 0.53 for swine housing (0.67 for shallow-pit houses); 0.48 for swine storage; 0.29 for broiler chickens; 0.70 for layer chickens; and 0.21 for beef feedlots (0.36 for beef feedlots with more farm-specific input data). Mean fractional error was found to be 22-44% for beef feedlots, swine housing, and layer housing; fractional errors were greater for swine lagoons (90%) and broiler housing (69%). Unexplained variability and errors result from model limitations, measurement errors in reported emissions factors, and a lack of information about measurement conditions.

  11. Recovery of bacteria from broiler carcasses after immersion chilling in different volumes of water, part 2.

    PubMed

    Northcutt, J K; Cason, J A; Ingram, K D; Smith, D P; Buhr, R J; Fletcher, D L

    2008-03-01

    Experiments were conducted to determine the relationship between poultry chilling water volume and carcass microbiology. In the first study, the volume of water used during immersion chilling was found to have a significant effect on the counts of bacteria recovered from broiler carcass halves; however, these volumes (2.1 and 16.8 L/kg) were extreme and did not reflect commercial levels. A second study using commercial chilling volumes was conducted with 3.3 L/kg (low) or 6.7 L/kg (high) distilled water in the chiller. Prechill broiler carcasses were removed from a commercial processing line, cut into left and right halves, and one-half of each pair was individually chilled in a bag containing low or high volume of water. Bags containing halves were submersed in a secondary chill tank containing approximately 150 L of an ice-water mix (0.6 degrees C). After 45 min, halves were removed, allowed to drip for 5 min, and rinsed with 100 mL of sterile water for 1 min. Rinses were analyzed for total aerobic bacteria, Escherichia coli, Enterobacteriaceae, and Campylobacter. When the numbers of bacteria in the half-carcass rinses (HCR) were compared, counts recovered from halves chilled in a low volume of water were the same as those recovered from the halves chilled with a high volume of water (P > 0.05). Levels found in the HCR ranged from 4.0 to 4.2 log(10) cfu/mL for aerobic bacteria, 3.3 to 3.5 log(10) cfu/mL for E. coli, 3.6 to 3.8 log(10) cfu/mL for Enterobacteriaceae, and 2.4 to 2.6 log(10) cfu/mL for Campylobacter. Data were also analyzed using a paired comparison t-test, and this analysis showed that there was no difference (P > 0.05) in the numbers of aerobic bacteria, E. coli, Enterobacteriaceae, or Campylobacter recovered from paired-halves chilled in different volumes of water. The present study shows that under the conditions outlined in this experiment, doubling the amount of water during immersion chilling (3.3 vs. 6.7 L/kg) did not improve the removal of

  12. Removal of ammonia from tarry water using a tubular furnace

    SciTech Connect

    V.V. Grabko; V.A. Kofanova; V.M. Li; M.A. Solov'ev

    2009-07-15

    An ammonia-processing system without the use of live steam from OAO Alchevskkoks plant's supply network is considered. Steam obtained from the wastewater that leaves the ammonia column is used to process the excess tarry water, with the release of volatile ammonia.

  13. Inhibiting Wet Oxidation of Ammonia

    NASA Technical Reports Server (NTRS)

    Onisko, D. B. L.

    1985-01-01

    Simple modification of wet-oxidation process for treating organicwaste reduces loss of fixed nitrogen, potentially valuable byproduct of process. Addition of sufficient sulfuric acid to maintain reaction pH below 3 greatly reduces oxidation of ammonia to free nitrogen. No equipment modification required.

  14. [Music-induced chills as a strong emotional experience].

    PubMed

    Mori, Kazuma; Iwanaga, Makoto

    2014-12-01

    While enjoying music and other works of art, people sometimes experience "chills," a strong emotional response characterized by a sensation of goose bumps or shivers. Such experiences differ from having goose bumps as a defense response or from shivering in reaction to cold temperatures. The current paper presents the phenomenon of music-induced chills and reviews the chill-related emotional response, autonomic nervous system activity, and brain activity. It also reviews the musico-acoustic features, listening contexts, and individual differences that cause chills. Based on the review, we propose a hypothetical model regarding the evocation of music-induced chills. Furthermore, we investigate the strong emotional response associated with chills by exploring the relationship between music-related chills and non-music-related chills, and discuss future research directions. PMID:25639033

  15. On the accretion process in a high-mass star forming region. A multitransitional THz Herschel-HIFI study of ammonia toward G34.26+0.15

    NASA Astrophysics Data System (ADS)

    Hajigholi, M.; Persson, C. M.; Wirström, E. S.; Black, J. H.; Bergman, P.; Olofsson, A. O. H.; Olberg, M.; Wyrowski, F.; Coutens, A.; Hjalmarson, Å.; Menten, K. M.

    2016-01-01

    Aims: Our aim is to explore the gas dynamics and the accretion process in the early phase of high-mass star formation. Methods: The inward motion of molecular gas in the massive star forming region G34.26+0.15 is investigated by using high-resolution profiles of seven transitions of ammonia at THz frequencies observed with Herschel-HIFI. The shapes and intensities of these lines are interpreted in terms of radiative transfer models of a spherical, collapsing molecular envelope. An accelerated Lambda Iteration (ALI) method is used to compute the models. Results: The seven ammonia lines show mixed absorption and emission with inverse P-Cygni-type profiles that suggest infall onto the central source. A trend toward absorption at increasingly higher velocities for higher excitation transitions is clearly seen in the line profiles. The J = 3 ← 2 lines show only very weak emission, so these absorption profiles can be used directly to analyze the inward motion of the gas. This is the first time a multitransitional study of spectrally resolved rotational ammonia lines has been used for this purpose. Broad emission is, in addition, mixed with the absorption in the 10-00 ortho-NH3 line, possibly tracing a molecular outflow from the star forming region. The best-fitting ALI model reproduces the continuum fluxes and line profiles, but slightly underpredicts the emission and absorption depth in the ground-state ortho line 10-00. An ammonia abundance on the order of 10-9 relative to H2 is needed to fit the profiles. The derived ortho-to-para ratio is approximately 0.5 throughout the infalling cloud core similar to recent findings for translucent clouds in sight lines toward W31C and W49N. We find evidence of two gas components moving inwards toward the central region with constant velocities: 2.7 and 5.3 km s-1, relative to the source systemic velocity. Attempts to model the inward motion with a single gas cloud in free-fall collapse did not succeed. Herschel is an ESA space

  16. The New Wind Chill Equivalent Temperature Chart.

    NASA Astrophysics Data System (ADS)

    Osczevski, Randall; Bluestein, Maurice

    2005-10-01

    The formula used in the U.S. and Canada to express the combined effect of wind and low temperature on how cold it feels was changed in November 2001. Many had felt that the old formula for equivalent temperature, derived in the 1960s from Siple and Passel's flawed but quite useful Wind Chill Index, unnecessarily exaggerated the severity of the weather. The new formula is based on a mathematical model of heat flow from the upwind side of a head-sized cylinder moving at walking speed into the wind. The paper details the assumptions that were made in generating the new wind chill charts. It also points out weaknesses in the concept of wind chill equivalent temperature, including its steady-state character and a seemingly paradoxical effect of the internal thermal resistance of the cylinder on comfort and equivalent temperature. Some improvements and alternatives are suggested.

  17. Ammonia stripping, activated carbon adsorption and anaerobic biological oxidation as process combination for the treatment of oil shale wastewater.

    PubMed

    Alexandre, Verônica M F; do Nascimento, Felipe V; Cammarota, Magali C

    2016-10-01

    Anaerobic biodegradability of oil shale wastewater was investigated after the following pretreatment sequence: ammonia stripping and activated carbon adsorption. Anaerobic biological treatment of oil shale wastewater is technically feasible after stripping at pH 11 for reducing the N-NH3 concentration, adsorption with 5 g/L of activated carbon in order to reduce recalcitrance and pH adjustment with CO2 so that the sulphate concentration in the medium remains low. After this pretreatment sequence, it was possible to submit the wastewater without dilution to an anaerobic treatment with 62.7% soluble chemical oxygen demand removal and specific methane production of 233.2 mL CH4STP/g CODremoved. PMID:27003628

  18. Decontaminating Aluminum/Ammonia Heat Pipes

    NASA Technical Reports Server (NTRS)

    Jones, J. A.

    1985-01-01

    Internal gas slugs reduced or eliminated. Manufacturing method increases efficiency of aluminum heat pipes in which ammonia is working fluid by insuring pipe filled with nearly pure charge of ammonia. In new process heat pipe initially closed with stainless-steel valve instead of weld so pipe put through several cycles of filling, purging, and accelerated aging.

  19. Ammonia emissions from land application of manures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia volatilization can be a major nitrogen (N) loss process for surface-applied manures. There is concern that current manure management practices are contributing to ammonia losses in the Mid-Atlantic region with subsequent reductions in air quality and increases in N losses to streams and est...

  20. Chilling stress response of post-emergent cotton seedlings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    • Early season development of cotton is often impaired by sudden episodes of chilling temperature. We determined the chilling response specific to post-emergent 13-d-old cotton seedlings. • Seedlings were gradually chilled during the dark period and rewarmed during the night-to-day transition. Fo...

  1. Cold Vacuum Drying (CVD) Facility Vacuum Purge System Chilled Water System Design Description (SYS 47-4)

    SciTech Connect

    IRWIN, J.J.

    2000-06-13

    This system design description (SDD) addresses the Vacuum Purge System Chilled Water (VPSCHW) system. The discussion that follows is limited to the VPSCHW system and its interfaces with associated systems. The reader's attention is directed to Drawings H-1-82162, Cold Vacuum Drying Facility Process Equipment Skid P&ID Vacuum System, and H-1-82224, Cold Vacuum Drying Facility Mechanical Utilities Process Chilled Water P&ID. Figure 1-1 shows the location and equipment arrangement for the VPSCHW system. The VPSCHW system provides chilled water to the Vacuum Purge System (VPS). The chilled water provides the ability to condense water from the multi-canister overpack (MCO) outlet gases during the MCO vacuum and purge cycles. By condensing water from the MCO purge gas, the VPS can assist in drying the contents of the MCO.

  2. A demonstration of chill block melt spinning of metal

    NASA Technical Reports Server (NTRS)

    Pond, Robert B.

    1990-01-01

    One of the most exciting adventures in materials in recent times has been the discovery of amorphous metals and the pursuit of methods of manufacturing various alloys into various shapes which are amorphous. Some of these alloys possess electrical properties which are extremely beneficial, whereas others offer different benefits such as corrosion resistence and no solidification shrinkage anomalies. There are a number of techniques for producing such amorphous shapes, but one of the earliest systems used is referred to as chill block melt spinning. The object of this demonstration is to show the simplicity of the process. The equipment and procedures are described.

  3. Catalytic Organometallic Reactions of Ammonia

    PubMed Central

    Klinkenberg, Jessica L.

    2012-01-01

    Until recently, ammonia had rarely succumbed to catalytic transformations with homogeneous catalysts, and the development of such reactions that are selective for the formation of single products under mild conditions has encountered numerous challenges. However, recently developed catalysts have allowed several classes of reactions to create products with nitrogen-containing functional groups from ammonia. These reactions include hydroaminomethylation, reductive amination, alkylation, allylic substitution, hydroamination, and cross-coupling. This Minireview describes examples of these processes and the factors that control catalyst activity and selectivity. PMID:20857466

  4. Argon purge gas cooled by chill box

    NASA Technical Reports Server (NTRS)

    Spiro, L. W.

    1966-01-01

    Cooling argon purge gas by routing it through a shop-fabricated chill box reduces charring of tungsten inert gas torch head components. The argon gas is in a cooled state as it enters the torch and prevents buildup of char caused by the high concentrations of heat in the weld area during welding operations.

  5. Guns on Campus: A Chilling Effect

    ERIC Educational Resources Information Center

    Mash, Kenneth M.

    2013-01-01

    The author of this article observes that, while much has been written on the overall topic of safety with regard to allowing guns on college campuses, little has been said about how allowing the possession of deadly weapons can create a "chilling effect" on academic discussions. This article considers how some universities have…

  6. Quality assessment of rainbow trout (Oncorhynchus mykiss) fillets during super chilling and chilled storage.

    PubMed

    Shen, Song; Jiang, Yan; Liu, Xiaochang; Luo, Yongkang; Gao, Liang

    2015-08-01

    In order to evaluate the effect of super chilling (-3 °C) and chilled (3 °C) storage on the quality of rainbow trout fillets, total volatile base nitrogen (TVB-N), drip loss, pH, electric conductivity (EC), total aerobic count (TAC), K and related values, adenosine triphosphate (ATP) and related compounds, color and sensory score were determined and correlation between these indicators were analyzed. According to the comprehensive evaluation of TAC, K value and sensory score, the limit for acceptability of rainbow trout fillets was 5 days at 3 °C and 11 days at -3 °C. Additionally, the correlation coefficients between TVB-N and other freshness indicators (TAC, K value, sensory score) were relatively low. TVB-N may be inadequate for evaluating freshness changes of rainbow trout fillets compared with other indicators. Among the K and related values, H value was a better freshness indicator in rainbow trout fillets during chilled and super chilling storage for its better correlation coefficients with other freshness indicators. Super chilling storage could extend the shelf life of rainbow trout fillets by 6 days compared to chilled storage. PMID:26243943

  7. Long-term toxicity and carcinogenicity test of ammonia-process caramel colouring given to B6C3F1 mice in the drinking-water.

    PubMed

    Hagiwara, A; Shibata, M; Kurata, Y; Seki, K; Fukushima, S; Ito, N

    1983-12-01

    Caramel colouring (ammonia process) was given at levels of 0 (control), 1.25 and 5.0% in the drinking-water to groups of 50 male and 50 female mice for 96 wk, and then all all the animals were maintained without caramel for a further 8 wk. Males given 5.0% caramel showed increased cumulative mortality from wk 100 to the end of the experiment. The white blood cell count in treated males was significantly elevated in a dose-related manner. However, these changes were not considered to be biologically significant. There were no treatment-related effects on clinical signs, body or organ weights, results of urine analyses, or histological features. Therefore, this study did not demonstrate any carcinogenic effect of caramel on mice at levels of up to 5.0% in the drinking-water. PMID:6686574

  8. Functionalization of Multiwalled Carbon Nanotubes by Solution Plasma Processing in Ammonia Aqueous Solution and Preparation of Composite Material with Polyamide 6

    NASA Astrophysics Data System (ADS)

    Shirafuji, Tatsuru; Noguchi, Yohei; Yamamoto, Taibou; Hieda, Junko; Saito, Nagahiro; Takai, Osamu; Tsuchimoto, Akiharu; Nojima, Kazuhiro; Okabe, Youji

    2013-12-01

    Solution plasma processing (SPP) has been performed on multiwalled carbon nanotubes (MWCNTs) in ammonia aqueous solution. The MWCNTs, which do not disperse in aqueous solution, uniformly dispersed after the SPP. Only 2 h was required to obtain 10 g of the dispersed MWCNTs, while 7 days and additional chemicals were required for 185 mg in a previous study. The X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy of the SPP-treated MWCNTs revealed that nitrogen- and oxygen-containing groups are formed on the MWCNTs. Serious damage to the MWCNT structure was not observed in the Raman spectrum or transmission electron microscopy images of the SPP-treated MWCNTs. The composite materials prepared using polyamide 6 with the SPP-treated MWCNTs showed better tensile, bending, and impact strength than those prepared with nontreated MWCNTs.

  9. Transcriptome Analysis of Pepper (Capsicum annuum) Revealed a Role of 24-Epibrassinolide in Response to Chilling

    PubMed Central

    Li, Jie; Yang, Ping; Kang, Jungen; Gan, Yantai; Yu, Jihua; Calderón-Urrea, Alejandro; Lyu, Jian; Zhang, Guobin; Feng, Zhi; Xie, Jianming

    2016-01-01

    Brassinosteroids (BRs) have positive effects on many processes during plant growth, development, and various abiotic stress responses. However, little information is available regarding the global gene expression of BRs in response to chilling stress in pepper. In this study, we used RNA sequencing to determine the molecular roles of 24-epibrassinolide (EBR) during a chilling stress response. There were 39,829 transcripts, and, among them, 656 were differently-expressed genes (DEGs) following EBR treatment (Chill+EBR) compared with the control (Chill only), including 335 up-regulated and 321 down-regulated DEGs. We selected 20 genes out of the 656 DEGs for RT-qPCR analysis to confirm the RNA-Seq. Based on GO enrich and KEGG pathway analysis, we found that photosynthesis was significantly up-enriched in biological processes, accompanied by significant increases in the net photosynthetic rate (Pn), Fv/Fm, and chlorophyll content. Furthermore, the results indicate that EBR enhanced endogenous levels of salicylic acid (SA) and jasmonic acid (JA) while suppressing the ethylene (ETH) biosynthesis pathway, suggesting that BRs function via a synergistic cross-talk with SA, JA, and ETH signaling pathways in response to chilling stress. In addition, EBR induced cellulose synthase-like protein and UDP-glycosyltransferase, suggesting a contribution to the formation of cell wall and hormone metabolism. EBR also triggered the calcium signaling transduction in cytoplasm, and activated the expression of cellular redox homeostasis related genes, such as GSTX1, PER72, and CAT2. This work, therefor, identified the specific genes showed different expression patterns in EBR-treated pepper and associated with the processes of hormone metabolism, redox, signaling, transcription, and defense. Our study provides the first evidence of the potent roles of BRs, at the transcription level, to induce the tolerance to chilling stress in pepper as a function of the combination of the

  10. Transcriptome Analysis of Pepper (Capsicum annuum) Revealed a Role of 24-Epibrassinolide in Response to Chilling.

    PubMed

    Li, Jie; Yang, Ping; Kang, Jungen; Gan, Yantai; Yu, Jihua; Calderón-Urrea, Alejandro; Lyu, Jian; Zhang, Guobin; Feng, Zhi; Xie, Jianming

    2016-01-01

    Brassinosteroids (BRs) have positive effects on many processes during plant growth, development, and various abiotic stress responses. However, little information is available regarding the global gene expression of BRs in response to chilling stress in pepper. In this study, we used RNA sequencing to determine the molecular roles of 24-epibrassinolide (EBR) during a chilling stress response. There were 39,829 transcripts, and, among them, 656 were differently-expressed genes (DEGs) following EBR treatment (Chill+EBR) compared with the control (Chill only), including 335 up-regulated and 321 down-regulated DEGs. We selected 20 genes out of the 656 DEGs for RT-qPCR analysis to confirm the RNA-Seq. Based on GO enrich and KEGG pathway analysis, we found that photosynthesis was significantly up-enriched in biological processes, accompanied by significant increases in the net photosynthetic rate (Pn), Fv/Fm, and chlorophyll content. Furthermore, the results indicate that EBR enhanced endogenous levels of salicylic acid (SA) and jasmonic acid (JA) while suppressing the ethylene (ETH) biosynthesis pathway, suggesting that BRs function via a synergistic cross-talk with SA, JA, and ETH signaling pathways in response to chilling stress. In addition, EBR induced cellulose synthase-like protein and UDP-glycosyltransferase, suggesting a contribution to the formation of cell wall and hormone metabolism. EBR also triggered the calcium signaling transduction in cytoplasm, and activated the expression of cellular redox homeostasis related genes, such as GSTX1, PER72, and CAT2. This work, therefor, identified the specific genes showed different expression patterns in EBR-treated pepper and associated with the processes of hormone metabolism, redox, signaling, transcription, and defense. Our study provides the first evidence of the potent roles of BRs, at the transcription level, to induce the tolerance to chilling stress in pepper as a function of the combination of the

  11. Chilling-Mediated DNA Methylation Changes during Dormancy and Its Release Reveal the Importance of Epigenetic Regulation during Winter Dormancy in Apple (Malus x domestica Borkh.)

    PubMed Central

    Kumar, Gulshan; Rattan, Usha Kumari; Singh, Anil Kumar

    2016-01-01

    Winter dormancy is a well known mechanism adopted by temperate plants, to mitigate the chilling temperature of winters. However, acquisition of sufficient chilling during winter dormancy ensures the normal phenological traits in subsequent growing period. Thus, low temperature appears to play crucial roles in growth and development of temperate plants. Apple, being an important temperate fruit crop, also requires sufficient chilling to release winter dormancy and normal phenological traits, which are often associated with yield and quality of fruits. DNA cytosine methylation is one of the important epigenetic modifications which remarkably affect the gene expression during various developmental and adaptive processes. In present study, methylation sensitive amplified polymorphism was employed to assess the changes in cytosine methylation during dormancy, active growth and fruit set in apple, under differential chilling conditions. Under high chill conditions, total methylation was decreased from 27.2% in dormant bud to 21.0% in fruit set stage, while no significant reduction was found under low chill conditions. Moreover, the demethylation was found to be decreased, while methylation increased from dormant bud to fruit set stage under low chill as compared to high chill conditions. In addition, RNA-Seq analysis showed high expression of DNA methyltransferases and histone methyltransferases during dormancy and fruit set, and low expression of DNA glcosylases during active growth under low chill conditions, which was in accordance with changes in methylation patterns. The RNA-Seq data of 47 genes associated with MSAP fragments involved in cellular metabolism, stress response, antioxidant system and transcriptional regulation showed correlation between methylation and their expression. Similarly, bisulfite sequencing and qRT-PCR analysis of selected genes also showed correlation between gene body methylation and gene expression. Moreover, significant association

  12. N2O emission in short-cut simultaneous nitrification and denitrification process: dynamic emission characteristics and succession of ammonia-oxidizing bacteria.

    PubMed

    Yan, Yingyan; Li, Ping; Wu, Jinhua; Zhu, Nengwu; Wu, Pingxiao; Wang, Xiangde

    2014-01-01

    A sequencing batch airlift reactor was used to investigate the characteristics of nitrous oxide (N2O) emission and the succession of an ammonia-oxidizing bacteria (AOB) community. The bioreactor could successfully switch from the complete simultaneous nitrification and denitrification (SND) process to the short-cut SND process by increasing the influent pH from 7.0-7.3 to 8.0-8.3. The results obtained showed that, compared with the complete SND process, the TN removal rate and SND efficiency were improved in the short-cut SND process by approximately 13 and 11%, respectively, while the amount of N2O emission was nearly three times larger than that in the complete SND process. The N2O emission was closely associated to nitrite accumulation. Analysis of the AOB microbial community showed that nitrifier denitrification by Nitrosomonas-like AOB could be an important pathway for the enhancement of N2O emission in the short-cut SND process. PMID:24960019

  13. DEAMOX--new biological nitrogen removal process based on anaerobic ammonia oxidation coupled to sulphide-driven conversion of nitrate into nitrite.

    PubMed

    Kalyuzhnyi, Sergey; Gladchenko, Marina; Mulder, Arnold; Versprille, Bram

    2006-11-01

    This paper reports about the successful laboratory testing of a new nitrogen removal process called DEAMOX (DEnitrifying AMmonium OXidation) for treatment of typical strong nitrogenous wastewater such as baker's yeast effluent. The concept of this process combines the recently discovered anammox (anaerobic ammonium oxidation) reaction with autotrophic denitrifying conditions using sulphide as an electron donor for the production of nitrite from nitrate within an anaerobic biofilm. To generate sulphide and ammonia, a Upflow Anaerobic Sludge Bed (UASB) reactor was used as a pre-treatment step. The UASB effluent was split and partially fed to a nitrifying reactor (to generate nitrate) and the remaining part was directly fed to the DEAMOX reactor where this stream was mixed with the nitrified effluent. Stable process performance and volumetric nitrogen loading rates of the DEAMOX reactor well above 1000 mgN/l/d with total nitrogen removal efficiencies of around 90% were obtained after long-term (410 days) optimisation of the process. Important prerequisites for this performance are appropriate influent ratios of the key species fed to the DEAMOX reactor, namely influent N-NO(x)/N-NH(4) ratios >1.2 (stoichiometry of the anammox reaction) and influent S-H(2)S/N-NO(3) ratios >0.57 mgS/mgN (stoichiometry of the sulphide-driven denitrification of nitrate to nitrite). The paper further describes some characteristics of the DEAMOX sludge as well as the preliminary results of its microbiological characterisation. PMID:16893559

  14. Pre-chill antimicrobial treatment to enhance the safety of chicken parts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: There is an increase in microbial prevalence as a chicken carcass transitions from a whole broiler to cut-up parts. One hypothesis to explain this occurrence is that bacteria in water retained during the pre-chill processing step is released upon cut-up, leading to contamination of chi...

  15. Growth of Salmonella on chilled meat.

    PubMed Central

    Mackey, B. M.; Roberts, T. A.; Mansfield, J.; Farkas, G.

    1980-01-01

    Growth rates of a mixture of Salmonella serotypes inoculated on beef from a commercial abattoir were measured at chill temperatures. The minimum recorded mean generation times were 8.1 h at 10 degrees C; 5.2 h at 12.5 degrees C and 2.9 h at 15 degrees C. Growth did not occur at 7-8 degrees C. From these data the maximum extent of growth of Salmonella during storage of meat for different times at chill temperatures was calculated. Criteria for deciding safe handling temperatures for meat are discussed. Maintaining an internal temperature below 10 degrees C during the boning operation would be sufficient to safeguard public health requirements. PMID:7052227

  16. Directional distribution of chilling winds in Estonia.

    PubMed

    Saue, Triin

    2016-08-01

    Wind chill equivalent temperature (WCET) is used to define thermal discomfort in winter months. Directional distributions of winds, which are associated with uncomfortable weather, were composed of three climatologically different Estonian locations: Vilsandi, Kuusiku, and Jõhvi. Cases with wind chill equivalent temperature <-10 °C, which could be classified as "uncomfortable or worse," were investigated. Additional thresholds were used to measure weather risk. The 25th percentile of daily minimum WCET was tested to measure classical prevalent wind directions in Estonia: W, SW, and NW bring warm air in winter from the North Atlantic, while winds from the East-European plain (NE, E, and SE) are associated with cold air. The eastern prevalence was stronger when a lower threshold was used. A directional approach may find several applications, such as building, agricultural, landscape, or settlement planning. PMID:26585350

  17. Directional distribution of chilling winds in Estonia

    NASA Astrophysics Data System (ADS)

    Saue, Triin

    2015-11-01

    Wind chill equivalent temperature (WCET) is used to define thermal discomfort in winter months. Directional distributions of winds, which are associated with uncomfortable weather, were composed of three climatologically different Estonian locations: Vilsandi, Kuusiku, and Jõhvi. Cases with wind chill equivalent temperature <-10 °C, which could be classified as "uncomfortable or worse," were investigated. Additional thresholds were used to measure weather risk. The 25th percentile of daily minimum WCET was tested to measure classical prevalent wind directions in Estonia: W, SW, and NW bring warm air in winter from the North Atlantic, while winds from the East-European plain (NE, E, and SE) are associated with cold air. The eastern prevalence was stronger when a lower threshold was used. A directional approach may find several applications, such as building, agricultural, landscape, or settlement planning.

  18. Directional distribution of chilling winds in Estonia

    NASA Astrophysics Data System (ADS)

    Saue, Triin

    2016-08-01

    Wind chill equivalent temperature (WCET) is used to define thermal discomfort in winter months. Directional distributions of winds, which are associated with uncomfortable weather, were composed of three climatologically different Estonian locations: Vilsandi, Kuusiku, and Jõhvi. Cases with wind chill equivalent temperature <-10 °C, which could be classified as "uncomfortable or worse," were investigated. Additional thresholds were used to measure weather risk. The 25th percentile of daily minimum WCET was tested to measure classical prevalent wind directions in Estonia: W, SW, and NW bring warm air in winter from the North Atlantic, while winds from the East-European plain (NE, E, and SE) are associated with cold air. The eastern prevalence was stronger when a lower threshold was used. A directional approach may find several applications, such as building, agricultural, landscape, or settlement planning.

  19. Identification of chilling-responsive microRNAs and their targets in vegetable soybean (Glycine max L.).

    PubMed

    Xu, Shengchun; Liu, Na; Mao, Weihua; Hu, Qizan; Wang, Guofu; Gong, Yaming

    2016-01-01

    Chilling stress is a major factor limiting the yield and quality of vegetable soybean (Glycine max L.) on a global scale. In the present study, systematic identification and functional analysis of miRNAs under chilling stress were carried out to clarify the molecular mechanism of chilling resistance. Two independent small RNA libraries from leaves of soybean were constructed and sequenced with the high-throughput Illumina Solexa system. A total of 434 known miRNAs and 3 novel miRNAs were identified. Thirty-five miRNAs were verified by qRT-PCR analysis. Furthermore, their gene targets were identified via high-throughput degradome sequencing. A total of 898 transcripts were targeted by 54 miRNA families attributed to five categories. More importantly, we identified 51 miRNAs differentially expressed between chilling stress and control conditions. The targets of these miRNAs were enriched in oxidation-reduction, signal transduction, and metabolic process functional categories. Our qRT-PCR analysis confirmed a negative relationship among the miRNAs and their targets under chilling stress. Our work thus provides comprehensive molecular evidence supporting the involvement of miRNAs in chilling-stress responses in vegetable soybean. PMID:27216963

  20. Identification of chilling-responsive microRNAs and their targets in vegetable soybean (Glycine max L.)

    PubMed Central

    Xu, Shengchun; Liu, Na; Mao, Weihua; Hu, Qizan; Wang, Guofu; Gong, Yaming

    2016-01-01

    Chilling stress is a major factor limiting the yield and quality of vegetable soybean (Glycine max L.) on a global scale. In the present study, systematic identification and functional analysis of miRNAs under chilling stress were carried out to clarify the molecular mechanism of chilling resistance. Two independent small RNA libraries from leaves of soybean were constructed and sequenced with the high-throughput Illumina Solexa system. A total of 434 known miRNAs and 3 novel miRNAs were identified. Thirty-five miRNAs were verified by qRT-PCR analysis. Furthermore, their gene targets were identified via high-throughput degradome sequencing. A total of 898 transcripts were targeted by 54 miRNA families attributed to five categories. More importantly, we identified 51 miRNAs differentially expressed between chilling stress and control conditions. The targets of these miRNAs were enriched in oxidation-reduction, signal transduction, and metabolic process functional categories. Our qRT-PCR analysis confirmed a negative relationship among the miRNAs and their targets under chilling stress. Our work thus provides comprehensive molecular evidence supporting the involvement of miRNAs in chilling-stress responses in vegetable soybean. PMID:27216963

  1. Economic uncertainties in chilled water system design

    SciTech Connect

    Kammerud, R.; Gillespie, K.L. Jr.; Hydeman, M.M.

    1999-07-01

    The analysis described here examines how uncertainties in engineering and economic assumptions made during chilled water system design translate to uncertainty in commonly used design decision metrics. The metric used is the benefit-cost ratio based on discounted cash flow. This analysis was performed as part of a project that is developing engineering tools for use in selecting energy-efficient chilled water system components, controls, and operating strategies. These tools include cooling thermal load prediction capabilities and performance data and models for chillers and cooling towers. The purpose of this study is to estimate accuracy requirements for the load and performance data that will be provided as part of the chilled water system tools. The logic is that there is inherent uncertainty in the decision metric due to uncertainty in inputs other than load and equipment performance, and, consequently, there is a limit below which further improvements in the accuracy of the load and equipment performance do not appreciably improve the quality of information available to the decision maker.

  2. Conversion of ammonia into hydrogen and nitrogen by reaction with a sulfided catalyst

    DOEpatents

    Matthews, Charles W.

    1977-01-01

    A method is provided for removing ammonia from the sour water stream of a coal gasification process. The basic steps comprise stripping the ammonia from the sour water; heating the stripped ammonia to a temperature from between 400.degree. to 1,000.degree. F; passing the gaseous ammonia through a reactor containing a sulfided catalyst to produce elemental hydrogen and nitrogen; and scrubbing the reaction product to obtain an ammonia-free gas. The residual equilibrium ammonia produced by the reactor is recycled into the stripper. The ammonia-free gas may be advantageously treated in a Claus process to recover elemental sulfur. Iron sulfide or cobalt molybdenum sulfide catalysts are used.

  3. Pretreatment of Biomass by Aqueous Ammonia for Bioethanol Production

    NASA Astrophysics Data System (ADS)

    Kim, Tae Hyun; Gupta, Rajesh; Lee, Y. Y.

    The methods of pretreatment of lignocellulosic biomass using aqueous ammonia are described. The main effect of ammonia treatment of biomass is delignification without significantly affecting the carbohydrate contents. It is a very effective pretreatment method especially for substrates that have low lignin contents such as agricultural residues and herbaceous feedstock. The ammonia-based pretreatment is well suited for simultaneous saccharification and co-fermentation (SSCF) because the treated biomass retains cellulose as well as hemicellulose. It has been demonstrated that overall ethanol yield above 75% of the theoretical maximum on the basis of total carbohydrate is achievable from corn stover pretreated with aqueous ammonia by way of SSCF. There are two different types of pretreatment methods based on aqueous ammonia: (1) high severity, low contact time process (ammonia recycle percolation; ARP), (2) low severity, high treatment time process (soaking in aqueous ammonia; SAA). Both of these methods are described and discussed for their features and effectiveness.

  4. Simulation Study of Al-1Mn/Al-10Si Circular Clad Ingots Prepared by Direct Chill Casting

    NASA Astrophysics Data System (ADS)

    Wu, Li; Kang, Huijun; Chen, Zongning; Fu, Ying; Wang, Tongmin

    2016-02-01

    A modified direct chill casting process based on Novelis FusionTM Technology co-casting process was used recently to prepare Al-1Mn/Al-10Si circular clad ingots. In the current study, a comprehensive simulation model was developed to investigate the direct chill casting process for preparing the Al-1Mn/Al-10Si circular clad ingots, and a parametric study and experimental research of the direct chill casting process was conducted to explore potential success and failure casting conditions. The simulation results revealed the bonding mechanism of the Al-1Mn/Al-10Si interface in the direct chill casting process and identified the effect of certain parameters on casting performance. The results indicated that the effect of casting speed and Al-1Mn casting temperature on the variations of the minimum solid fraction of Al-1Mn at the interface is stronger than that of cooling water flow rate in inner mold, while Al-10Si casting temperature is the weakest of the four casting parameters. The corresponding experimental results verified that Al-1Mn/Al-10Si circular clad ingot with acceptable metallurgical bonding can be successfully prepared by direct chill casting process under the proper casting parameters. The thickness of diffusion zone is about 40 μm, and the fractured position in tensile test was located in the Al-1Mn alloy side which indicated the strength of the interfacial region is higher than that of Al-1Mn alloy.

  5. Simultaneous removal of ammonia, P and COD from anaerobically digested piggery wastewater using an integrated process of chemical precipitation and air stripping.

    PubMed

    Quan, Xuejun; Ye, Changying; Xiong, Yanqi; Xiang, Jinxin; Wang, Fuping

    2010-06-15

    The paper presented an efficient integrated physicochemical process, which consists of chemical precipitation and air stripping, for the simultaneous removal of NH(3)-N, total P and COD from anaerobically digested piggery wastewater. In the integrated process, Ca(OH) (2) was used as the precipitant for NH(4)(+), PO(4)(3-) and organic phosphorous compounds, and as the pH adjuster for the air stripping of residual ammonia. The possibility of the suggested process and the related mechanisms were first investigated through a series of equilibrium tests. Laboratory scale tests were carried out to validate the application possibility of the integrated process using a new-patented water sparged aerocyclone reactor (WSA). The WSA could be effectively used for the simultaneous removal of NH(3)-N, total P and COD. 3g/L of Ca(OH) (2) is a proper dosage for the simultaneous removal. The simultaneous removal of NH(3)-N, total P and COD in the WSA reactor could be easily optimized by selecting a proper air inlet velocity and a proper jet velocity of the liquid phase. In all the cases, the removal efficiencies of the NH(3)-N, total P and COD were over 91%, 99.2% and 52% for NH(3)-N, total P and COD, respectively. The formed precipitates in the process could be easily settled down from the suspension system. Therefore, the integrated process provided an efficient alternative for the simultaneous removal of NH(3)-N, total P and COD from the wastewater. PMID:20189301

  6. Bacteria recovery from genetically feathered and featherless broiler carcasses after immersion chilling.

    PubMed

    Buhr, R J; Bourassa, D V; Northcutt, J K; Hinton, A; Ingram, K D; Cason, J A

    2005-09-01

    Feathered and featherless (scaleless) sibling broilers were reared and processed together to evaluate the influence of feathers and feather follicles on carcass bacteria recovery after chilling. In each experiment, broilers were inoculated 1 wk prior to processing by oral gavage with a suspension of salmonellae or Campylobacter at 106 cells/mL. Broilers were stunned and bled, and carcasses were single-tank or triple-tank scalded, defeathered, eviscerated, and washed. Carcasses were chilled for 45 min in ice and water immersion chillers with or without 20 mg of chlorine/L added. Postchill carcass rinsates were evaluated for Escherichia coli, coliforms, total aerobes, and salmonellae or Campylobacter. Following processing and immersion chilling, genetically featherless carcasses had slightly higher counts (by log10 0.35 cfu/100 mL of carcass rinsate) for E. coli, coliforms, and total aerobes than feathered carcasses. However, there were no significant differences in the prevalence of salmonellae (25%) or Campylobacter (93%) between feathered and featherless carcasses. Recovery of E. coli, coliforms, and total aerobic bacteria were lower for carcasses that were single-tank scalded, and following enrichment, salmonellae were recovered from fewer carcasses subjected to the single-tank (71%) than triple-tank (86%) scalding. Addition of chlorine to chiller water significantly decreased carcass bacteria recovery (by log10 0.43 cfu/100 mL of carcass rinsate) for E. coli, coliforms, total aerobes, and Campylobacter but did not affect salmonellae recovery. The presence of feathers and feather follicles during processing and immersion chilling appears to have minimal influence on the recovery of salmonellae or Campylobacter from carcasses sampled after immersion chilling. PMID:16206575

  7. Assessing Ammonia Treatment Options

    EPA Science Inventory

    This is the second of three articles to help water system operators understand ammonia and how to monitor and control its effects at the plant and in the distribution system. The first article (Opflow, April 2012) provided an overview of ammonia's chemistry, origins, and water sy...

  8. Method for forming ammonia

    DOEpatents

    Kong, Peter C.; Pink, Robert J.; Zuck, Larry D.

    2008-08-19

    A method for forming ammonia is disclosed and which includes the steps of forming a plasma; providing a source of metal particles, and supplying the metal particles to the plasma to form metal nitride particles; and providing a substance, and reacting the metal nitride particles with the substance to produce ammonia, and an oxide byproduct.

  9. Ethylene Production by Chilled Cucumbers (Cucumis sativus L.).

    PubMed

    Wang, C Y; Adams, D O

    1980-11-01

    Chilling at 2.5 C accelerated the synthesis of 1-aminocyclopropane-1-carboxylic acid (ACC) and C(2)H(4) production in cucumber fruit. Skin tissue contained higher levels of ACC and was more sensitive to chilling than was cortex tissue. Accumulation of ACC in chilled tissue was detected after 1 day of chilling and remained elevated even after C(2)H(4) production started to decline. These data suggest that ACC synthesis is readily stimulated by chilling, whereas the system that converts ACC to C(2)H(4) is vulnerable to chilling injury. Chilling-induced C(2)H(4) production was inhibited by amino-ethoxyvinylglycine, sodium benzoate, propyl gallate, 2,4-dinitrophenol, carbonyl cyanide m-chlorophenylhydrazone, and cycloheximide. The utilization of methionine for ACC formation and chilling-induced C(2)H(4) biosynthesis was established using l-[3,4-(14)C]methionine. Chilled tissue had a higher capacity to convert l-[3,4-(14)C]methionine to ACC and C(2)H(4) than did nonchilled tissue. PMID:16661538

  10. Ethylene Production by Chilled Cucumbers (Cucumis sativus L.) 1

    PubMed Central

    Wang, Chien Yi; Adams, Douglas O.

    1980-01-01

    Chilling at 2.5 C accelerated the synthesis of 1-aminocyclopropane-1-carboxylic acid (ACC) and C2H4 production in cucumber fruit. Skin tissue contained higher levels of ACC and was more sensitive to chilling than was cortex tissue. Accumulation of ACC in chilled tissue was detected after 1 day of chilling and remained elevated even after C2H4 production started to decline. These data suggest that ACC synthesis is readily stimulated by chilling, whereas the system that converts ACC to C2H4 is vulnerable to chilling injury. Chilling-induced C2H4 production was inhibited by amino-ethoxyvinylglycine, sodium benzoate, propyl gallate, 2,4-dinitrophenol, carbonyl cyanide m-chlorophenylhydrazone, and cycloheximide. The utilization of methionine for ACC formation and chilling-induced C2H4 biosynthesis was established using l-[3,4-14C]methionine. Chilled tissue had a higher capacity to convert l-[3,4-14C]methionine to ACC and C2H4 than did nonchilled tissue. PMID:16661538

  11. Ultrafast Dynamics of Electrons in Ammonia

    NASA Astrophysics Data System (ADS)

    Vöhringer, Peter

    2015-04-01

    Solvated electrons were first discovered in solutions of metals in liquid ammonia. The physical and chemical properties of these species have been studied extensively for many decades using an arsenal of electrochemical, spectroscopic, and theoretical techniques. Yet, in contrast to their hydrated counterpart, the ultrafast dynamics of ammoniated electrons remained completely unexplored until quite recently. Femtosecond pump-probe spectroscopy on metal-ammonia solutions and femtosecond multiphoton ionization spectroscopy on the neat ammonia solvent have provided new insights into the optical properties and the reactivities of this fascinating species. This article reviews the nature of the optical transition, which gives the metal-ammonia solutions their characteristic blue appearance, in terms of ultrafast relaxation processes involving bound and continuum excited states. The recombination processes following the injection of an electron via photoionization of the solvent are discussed in the context of the electronic structure of the liquid and the anionic defect associated with the solvated electron.

  12. Ultrafast dynamics of electrons in ammonia.

    PubMed

    Vöhringer, Peter

    2015-04-01

    Solvated electrons were first discovered in solutions of metals in liquid ammonia. The physical and chemical properties of these species have been studied extensively for many decades using an arsenal of electrochemical, spectroscopic, and theoretical techniques. Yet, in contrast to their hydrated counterpart, the ultrafast dynamics of ammoniated electrons remained completely unexplored until quite recently. Femtosecond pump-probe spectroscopy on metal-ammonia solutions and femtosecond multiphoton ionization spectroscopy on the neat ammonia solvent have provided new insights into the optical properties and the reactivities of this fascinating species. This article reviews the nature of the optical transition, which gives the metal-ammonia solutions their characteristic blue appearance, in terms of ultrafast relaxation processes involving bound and continuum excited states. The recombination processes following the injection of an electron via photoionization of the solvent are discussed in the context of the electronic structure of the liquid and the anionic defect associated with the solvated electron. PMID:25493716

  13. Effect of catalyst on electrolysis of ammonia effluents

    NASA Astrophysics Data System (ADS)

    Bonnin, Egilda P.; Biddinger, Elizabeth J.; Botte, Gerardine G.

    The electrolysis of ammonia (NH 3) was studied as a remediation process for the removal of ammonia from wastewater, with the advantage of producing hydrogen while returning clean water to the environment. An electro-catalyst able to support the electro-oxidation of ammonia at low concentrations was designed. Two substrates were tested, Raney nickel and carbon fiber. Carbon fiber was found to be a better substrate for the electrolysis of ammonia at low concentrations. The performance of noble metals such as Rh, Pt and Ir, electroplated on the carbon fiber substrate was also evaluated. Rh-Pt-Ir and Pt-Ir on carbon fiber substrate were found to be the most promising electrodes for the electrolysis of ammonia at low concentrations. The maximum ammonia conversion was 91.49 ± 0.01% for a typical concentration of ammonia found in sewage water and the Faradaic efficiency was 91.81 ± 0.13% on the selected anode.

  14. The big chill: accidental hypothermia.

    PubMed

    Davis, Robert Allan

    2012-01-01

    A potential cause of such emergent issues as cardiac arrhythmias, hypotension, and fluid and electrolyte shifts, accidental hypothermia can be deadly, is common among trauma patients, and is often difficult to recognize. The author discusses predisposing conditions, the classic presentation, and the effects on normal thermoregulatory processes; explains how to conduct a systems assessment of the hypothermic patient; and describes crucial management strategies. PMID:22186703

  15. Rested and stressed farmed Atlantic cod (Gadus morhua) chilled in ice or slurry and effects on quality.

    PubMed

    Digre, Hanne; Erikson, Ulf; Aursand, Ida G; Gallart-Jornet, Lorena; Misimi, Ekrem; Rustad, Turid

    2011-01-01

    The main objectives of this study were to investigate (1) whether rested harvest of farmed cod was better maintained by chilling with slurry rather than by traditional ice storage, (2) whether chilling with slurry would be a feasible chilling method to assure low core temperatures (≤0 °C) at packing of gutted fish, and (3) the effects of superchilling compared with traditional ice on selected quality parameters of cod during storage. In the experiment, seawater slurry at -2.0 ± 0.3 °C was used. Anesthetized (AQUI-S™), percussion stunned, and stressed cod chilled in slurry were compared. Cod stored on ice were used as reference group. The fish were evaluated at the day of slaughter, and after 7 and 14 d of storage according to handling stress (initial muscle pH, muscle twitches, rigor mortis), core temperatures, quality index method, microbial counts, weight changes, salt and water content, water distribution, pH, adenosine triphosphate-degradation products, K-value, water-holding capacity, fillet color, and texture. Chilling cod in slurry was more rapid than chilling in ice. Prechilling (1 d) of cod in slurry before subsequent ice storage resulted in lower quality 7 d postmortem compared with both ice and continuous slurry storage. The potential advantages of superchilling became more prominent after 14 d with lower microbiological activity, better maintenance of freshness (lower total quality index scores and lower K-values) compared with fish stored on ice. A drawback with slurry-stored fish was that cloudy eyes developed earlier, in addition to weight gain and salt uptake compared to ice-stored fish. Practical Application: Chilling is an essential operation in any fish-processing plant. This manuscript addresses different applications of slurry ice in the processing and storage of Atlantic cod. Cod quality was assessed after 7 and 14 d of iced and superchilled storage. PMID:21535722

  16. Tomato flavor changes at chilling and non-chilling temperatures as influenced by controlled atmospheres

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Postharvest temperatures recommended as safe to avoid chilling injury (CI) based on lack of visible symptoms suppress tomato aroma development. We investigated how temperatures at or above the putative CI threshold of 12.5°C affected aroma of pink ‘Tasti Lee’ tomatoes and if controlled atmosphere (C...

  17. Waste Heat Powered Ammonia Absorption Refrigeration Unit for LPG Recovery

    SciTech Connect

    Donald C, Energy Concepts Co.; Lauber, Eric, Western Refining Co.

    2008-06-20

    An emerging DOE-sponsored technology has been deployed. The technology recovers light ends from a catalytic reformer plant using waste heat powered ammonia absorption refrigeration. It is deployed at the 17,000 bpd Bloomfield, New Mexico refinery of Western Refining Company. The technology recovers approximately 50,000 barrels per year of liquefied petroleum gas that was formerly being flared. The elimination of the flare also reduces CO2 emissions by 17,000 tons per year, plus tons per year reductions in NOx, CO, and VOCs. The waste heat is supplied directly to the absorption unit from the Unifiner effluent. The added cooling of that stream relieves a bottleneck formerly present due to restricted availability of cooling water. The 350oF Unifiner effluent is cooled to 260oF. The catalytic reformer vent gas is directly chilled to minus 25oF, and the FCC column overhead reflux is chilled by 25oF glycol. Notwithstanding a substantial cost overrun and schedule slippage, this project can now be considered a success: it is both profitable and highly beneficial to the environment. The capabilities of directly-integrated waste-heat powered ammonia absorption refrigeration and their benefits to the refining industry have been demonstrated.

  18. Performance of a chill ATES system

    SciTech Connect

    Midkiff, K.C.; Song, Y.K.; Schaetzle, W.J.

    1989-03-01

    An aquifer air-conditioning system has been installed to cool the Student Recreation Center on the University of Alabama Campus. This research program encompasses the monitoring of the operation of the aquifer system and provision of emplacements to the system. The monitoring includes establishing the instrumentation, acquiring data, and analyzing the results. The instrumentation allows the measurement of water flow rates and corresponding temperatures, electrical energy input, aquifer temperatures at nineteen monitoring wells, and aquifer levels at six monitoring wells. Recent acquifer performance data indicate that 76% of the chill energy stored was recovered for the period Oct/86 - Sep/87 and 70% for the period Oct/87 - Sep/88. This is a substantial improvement over recoveries of 38% for the 1985 season and 55% for 1986. The overall coefficient of performance was 5.4 for Oct/86 - Sep/87 and 4.6 for Oct/87 - Sep/88. THe system has supplied 100% of the cooling with only about one-half of the energy input required by a conventional system. Some of the increased recovery of chilled water is a result of modifying the production well operation to reduce the regional flow of water toward the northwest. All warm water is withdrawn form the southeast wells, chilled, and injected in northwest wells. The cold water then withdrawn from the cold wells is used for air-conditioning but not reinjected into the aquifer. Additional flow control is provided by pumping (and discarding) water out of a southeast well, although the complete results of this new strategy are as yet unclear.

  19. Ammonia Leak Locator Study

    NASA Technical Reports Server (NTRS)

    Dodge, Franklin T.; Wuest, Martin P.; Deffenbaugh, Danny M.

    1995-01-01

    The thermal control system of International Space Station Alpha will use liquid ammonia as the heat exchange fluid. It is expected that small leaks (of the order perhaps of one pound of ammonia per day) may develop in the lines transporting the ammonia to the various facilities as well as in the heat exchange equipment. Such leaks must be detected and located before the supply of ammonia becomes critically low. For that reason, NASA-JSC has a program underway to evaluate instruments that can detect and locate ultra-small concentrations of ammonia in a high vacuum environment. To be useful, the instrument must be portable and small enough that an astronaut can easily handle it during extravehicular activity. An additional complication in the design of the instrument is that the environment immediately surrounding ISSA will contain small concentrations of many other gases from venting of onboard experiments as well as from other kinds of leaks. These other vapors include water, cabin air, CO2, CO, argon, N2, and ethylene glycol. Altogether, this local environment might have a pressure of the order of 10(exp -7) to 10(exp -6) torr. Southwest Research Institute (SwRI) was contracted by NASA-JSC to provide support to NASA-JSC and its prime contractors in evaluating ammonia-location instruments and to make a preliminary trade study of the advantages and limitations of potential instruments. The present effort builds upon an earlier SwRI study to evaluate ammonia leak detection instruments [Jolly and Deffenbaugh]. The objectives of the present effort include: (1) Estimate the characteristics of representative ammonia leaks; (2) Evaluate the baseline instrument in the light of the estimated ammonia leak characteristics; (3) Propose alternative instrument concepts; and (4) Conduct a trade study of the proposed alternative concepts and recommend promising instruments. The baseline leak-location instrument selected by NASA-JSC was an ion gauge.

  20. Increasing chilling reduces heat requirement for floral budbreak in peach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Response to chilling temperatures is a critical factor in the suitability of peach [Prunus persica (L.) Batsch] cultivars to moderate climates such as in the southeastern United States. Time of bloom depends on the innate chilling requirement of the cultivar as well as the timing and quantity of co...

  1. 76 FR 166 - Fresh and Chilled Atlantic Salmon From Norway

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-03

    ... imports of fresh and chilled Atlantic salmon from Norway (56 FR 14920, 14921). Following five-year reviews... imports of fresh and chilled Atlantic salmon from Norway (71 FR 7512). The Commission is now conducting...), as most recently amended at 74 FR 2847 (January 16, 2009). \\1\\ \\1\\ No response to this request...

  2. Incidence of chilling injury in fresh-cut 'Kent' mangoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The preferred storage temperature for fresh-cut fruits in terms of visual quality retention is around 5 °C, which is considered to be a chilling temperature for chilling sensitive tropical fruits like mango (Mangifera indica L.). Changes in visual and compositional quality factors, aroma volatile pr...

  3. Chilling and heat requirements for flowering in temperate fruit trees

    NASA Astrophysics Data System (ADS)

    Guo, Liang; Dai, Junhu; Ranjitkar, Sailesh; Yu, Haiying; Xu, Jianchu; Luedeling, Eike

    2014-08-01

    Climate change has affected the rates of chilling and heat accumulation, which are vital for flowering and production, in temperate fruit trees, but few studies have been conducted in the cold-winter climates of East Asia. To evaluate tree responses to variation in chill and heat accumulation rates, partial least squares regression was used to correlate first flowering dates of chestnut ( Castanea mollissima Blume) and jujube ( Zizyphus jujube Mill.) in Beijing, China, with daily chill and heat accumulation between 1963 and 2008. The Dynamic Model and the Growing Degree Hour Model were used to convert daily records of minimum and maximum temperature into horticulturally meaningful metrics. Regression analyses identified the chilling and forcing periods for chestnut and jujube. The forcing periods started when half the chilling requirements were fulfilled. Over the past 50 years, heat accumulation during tree dormancy increased significantly, while chill accumulation remained relatively stable for both species. Heat accumulation was the main driver of bloom timing, with effects of variation in chill accumulation negligible in Beijing's cold-winter climate. It does not seem likely that reductions in chill will have a major effect on the studied species in Beijing in the near future. Such problems are much more likely for trees grown in locations that are substantially warmer than their native habitats, such as temperate species in the subtropics and tropics.

  4. Diurnal variation of wind-chill at Thessaloniki, Greece

    NASA Astrophysics Data System (ADS)

    Balafoutis, Ch. J.

    1989-12-01

    The diurnal variations of wind-chill at Thessaloniki, Greece, are considered using hourly data from January 1960 to December 1977. This is the first attempt in Greece to describe bioclimatic conditions using wind-chill data. The hourly values of wind-chill were calculated by Siple-Passel's formula which still appears to be most widely used. The values of wind-chill are discussed in terms of Terjung's scale. Thessaloniki does not experience “frost-bite” conditions during the coldest months but does experience “warm” conditions during the summer period. A comparison of hourly and daily mean values show that the means do not indicate the real range of wind-chill during the day.

  5. Sugar metabolism in relation to chilling tolerance of loquat fruit.

    PubMed

    Cao, Shifeng; Yang, Zhenfeng; Zheng, Yonghua

    2013-01-01

    The relationship between chilling injury and sugar metabolism was investigated in loquat fruit stored at 1°C for 35days. No symptoms of chilling injury occurred in the fruit, of 'Ninghaibai' cultivar, during the whole storage whereas, in 'Dahongpao' fruit, severe chilling symptoms were observed after 20days of storage at 1°C. 'Ninghaibai' fruit had higher levels of glucose and fructose and higher activities of sucrose hydrolyzing enzymes, such as sucrose synthase-cleavage and invertase, than had 'Dahongpao'. Furthermore, the chilling resistant 'Ninghaibai' fruit also showed higher activities of hexokinase and fructokinase, involved in hexose phoshorylation and sugar signal generation. These results suggest that the higher content of hexoses and activities of hexose sensors were likely part of the mechanism for chilling tolerance of loquat fruit. PMID:23017404

  6. Effects of chilling on protein synthesis in tomato suspension cultures

    SciTech Connect

    Matadial, B.; Pauls, K.P. )

    1989-04-01

    The effect of chilling on cell growth, cell viability, protein content and protein composition in suspension cultures of L. esculentum and L. hirsutum was investigated. Cell growth for both species was arrested at 2{degrees}C but when cultures were transferred to 25{degree}C cell growth resumed. There was no difference in viability between control and chilled cultures of L. esculentum, however, L. hirsutum control cultures exhibited larger amounts of Fluorescein Diacetate induced fluorescence than chilled cultures. {sup 35}S-methionine incorporation into proteins was 2.5-2 times higher in L. hirsutum than in L. esculentum. Quantitative and qualitative differences, in {sup 35}S-methionine labelled proteins, between chilled and control cultures were observed by SDS-PAGE and fluorography. Protein content in chilled cultures decreased over time but then increased when cultures were transferred to 25{degrees}C.

  7. The Chilled-Mirror Humidity Sensor: Improved Radiosonde Measurements

    NASA Technical Reports Server (NTRS)

    Schmidlin, F. J.

    1999-01-01

    Chilled-mirror humidity sensor technology recently was adapted for use with the VIZ radiosonde. The principle of the chilled-mirror operation is to lower its temperature until dew forms on the mirror, at that point the dew point temperature is noted and the mirror is then heated to evaporate the moisture. The cycle is repeated. Research conducted from NASA's Wallops Flight Facility has provided comparisons between the chilled-mirror sensor and the carbon hygristor of VIZ, and the capacitive sensors of AIR Inc. and Vaisala Co. We believe the chilled-mirror sensor is accurate and would serve as a reference standard for evaluating operational radiosonde relative humidity sensors. Thus, differences seen in the comparisons are beginning to furnish insight into developing better humidity sensors. We discuss these comparison results as well as reproducibility results from a dual chilled-mirror measurement.

  8. Ammonia Release on ISS

    NASA Technical Reports Server (NTRS)

    Macatangay, Ariel

    2009-01-01

    Crew: Approximately 53% metabolic load Product of protein metabolism Limit production of ammonia by external regulation NOT possbile Payloads Potential source Scientific experiments Thorough safety review ensures sufficient levels of containment

  9. Reactor for removing ammonia

    DOEpatents

    Luo, Weifang; Stewart, Kenneth D.

    2009-11-17

    Disclosed is a device for removing trace amounts of ammonia from a stream of gas, particularly hydrogen gas, prepared by a reformation apparatus. The apparatus is used to prevent PEM "poisoning" in a fuel cell receiving the incoming hydrogen stream.

  10. Ammonia and sediment toxicity

    SciTech Connect

    Ogle, R.S.; Hansen, S.R.

    1994-12-31

    Ammonia toxicity to aquatic organisms has received considerable study, with most of these studies focusing on water column organisms. However, with the development and implementation of sediment (and pore water) toxicity tests, the toxicity of ammonia to benthic infauna and other sediment toxicity test organisms has become important, especially since sediment/porewater ammonia occurs at higher concentrations than in the water column. Unfortunately, there has been very little of this type information, especially for marine/estuarine organisms. This laboratory determined the toxicity of ammonia to three key marine/estuarine test organisms: the amphipod Eohaustorius estuarius, the bivalve Mytilus edulis, and the echinoderm Strongylocentrotus purpuratus. Because sediment/porewater pH can differ substantially from typical seawater pH, the toxicity evaluations covered a range of pH levels (6, 7, 8, and 9). Eohaustorius results indicate that while Total Ammonia increased in toxicity (measured as EC50) as pH increased (from 460 mg/L at pH 6, to 13 mg/L at pH 9), unionized ammonia toxicity decreased from 0.13 mg/L at pH 6 to 2.8 mg/L at pH 9. The amphipod was much less sensitive to ammonia than were the bivalve and echinoderm, with an unionized ammonia EC50 at pH 8 of 2.14 mg/L relative to 0.43 mg/L for the mussel and 0.13 mg/L for the purple urchin. These results are discussed with respect to design and interpretation of sediment toxicity test results, including an interpretation approach based on partitioning of Toxic Units (TU).

  11. Titan's Ammonia Feature

    NASA Technical Reports Server (NTRS)

    Smythe, W.; Nelson, R.; Boryta, M.; Choukroun, M.

    2011-01-01

    NH3 has long been considered an important component in the formation and evolution of the outer planet satellites. NH3 is particularly important for Titan, since it may serve as the reservoir for atmospheric nitrogen. A brightening seen on Titan starting in 2004 may arise from a transient low-lying fog or surface coating of ammonia. The spectral shape suggests the ammonia is anhydrous, a molecule that hydrates quickly in the presence of water.

  12. Ammonia Clouds on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Click on the image for movie of Ammonia Ice Clouds on Jupiter

    In this movie, put together from false-color images taken by the New Horizons Ralph instrument as the spacecraft flew past Jupiter in early 2007, show ammonia clouds (appearing as bright blue areas) as they form and disperse over five successive Jupiter 'days.' Scientists noted how the larger cloud travels along with a small, local deep hole.

  13. The nitrate to ammonia and ceramic (NAC) process for the denitration and immobilization of low-level radioactive liquid waste (LLW)

    NASA Astrophysics Data System (ADS)

    Muguercia, Ivan

    Hazardous radioactive liquid waste is the legacy of more than 50 years of plutonium production associated with the United States' nuclear weapons program. It is estimated that more than 245,000 tons of nitrate wastes are stored at facilities such as the single-shell tanks (SST) at the Hanford Site in the state of Washington, and the Melton Valley storage tanks at Oak Ridge National Laboratory (ORNL) in Tennessee. In order to develop an innovative, new technology for the destruction and immobilization of nitrate-based radioactive liquid waste, the United State Department of Energy (DOE) initiated the research project which resulted in the technology known as the Nitrate to Ammonia and Ceramic (NAC) process. However, inasmuch as the nitrate anion is highly mobile and difficult to immobilize, especially in relatively porous cement-based grout which has been used to date as a method for the immobilization of liquid waste, it presents a major obstacle to environmental clean-up initiatives. Thus, in an effort to contribute to the existing body of knowledge and enhance the efficacy of the NAC process, this research involved the experimental measurement of the rheological and heat transfer behaviors of the NAC product slurry and the determination of the optimal operating parameters for the continuous NAC chemical reaction process. Test results indicate that the NAC product slurry exhibits a typical non-Newtonian flow behavior. Correlation equations for the slurry's rheological properties and heat transfer rate in a pipe flow have been developed; these should prove valuable in the design of a full-scale NAC processing plant. The 20-percent slurry exhibited a typical dilatant (shear thickening) behavior and was in the turbulent flow regime due to its lower viscosity. The 40-percent slurry exhibited a typical pseudoplastic (shear thinning) behavior and remained in the laminar flow regime throughout its experimental range. The reactions were found to be more efficient in the

  14. Release of ammonia from HAN-type PHA

    SciTech Connect

    Zamecnik, J.R.

    1992-06-10

    A preliminary design basis for ammonia scrubbers in the DWPF has been issued. This design basis is based on a theoretical model of ammonia evolution from the SRAT, SME and RCT. It is desirable to acquire actual process data on ammonia evolution prior to performing detailed design of scrubbers for DWPF. The evolution of ammonia from the SRAT and SME in the Integrated DWPF Melter System (IDMS) was investigated during the HM4 run. In this run, Precipitate Hydrolysis Aqueous (PHA), which was made in the Precipitate Hydrolysis Experimental Facility (PHEF) using the HAN (hydroxylamine nitrate) process was used, thus resulting in PHA with a high concentration of ammonium ion.

  15. Application of Internal Fusible Chills in Thick-Walled Castings Made of EN-GJS with an Optimized Microstructure

    NASA Astrophysics Data System (ADS)

    Krupa, Wojciech; Tonn, Babette

    2011-01-01

    The degeneration of graphite in thick-walled components made of ductile iron due to slower solidification affects the mechanical properties and is unacceptable for all safety-relevant components. The inoculation of the melt no longer leads to a fine microstructure. After exceeding the critical solidification time, degenerated shapes of graphite are to be expected. The external cooling with a chill-mould does not eliminate graphite degeneration in the thermal centres. The positive effect of these chills is also limited by the wall thickness. The aim of this study was to increase the heat dissipation of the melt by positioning the internal fusible chills in the thermal centre of the mould cavity. This should lead to accelerated solidification. The plate-shaped chills were placed in the middle of rectangular samples. The solidification processes were first simulated with Magmasoft in order to optimize the size and shape of the fusible chills and to thus guarantee a complete dissolving of the chills. A reduction in the solidification time of approximately 15% was achieved. In the experiments thick-walled samples were cast with and without internal fusible chills and compared. Areas with degenerated graphite, including chunky graphite, were found in the centres of the cast samples without internal cooling. Placing fusible chills in castings increased the number of graphite spheroids in the microstructure and exhibited no graphite degeneration. A homogenous microstructure was developed—no residues of the chills were found. Differences in microstructure and mechanical properties between the edges and centres of the casting could be nullified. The optimized graphite morphology of the casting with internal cooling led to an increase in tensile strength in the thermal centre of about 30 MPa (8%). This process was successfully implemented in an industrial environment. Blocks out of EN-GJS-400 for use in hydraulic engineering with a total weight of eight tonnes were cast in

  16. Reactions of dehydrodiferulates with ammonia.

    PubMed

    Azarpira, Ali; Lu, Fachuang; Ralph, John

    2011-10-01

    Lignocellulosic materials derived from forages and agricultural residues are potential sustainable resources for production of bioethanol or other liquid biofuels. However, the natural recalcitrance of such materials to enzymatic hydrolysis is a major obstacle in their efficient utilization. In grasses, much of the recalcitrance is associated with ferulate cross-linking in the cell wall, i.e., with polysaccharide-polysaccharide cross-linking that results from ferulate dehydrodimerization or with lignin-polysaccharide cross-linking that results from the incorporation of (polysaccharide-bound) ferulates or diferulates into lignin, mainly via free-radical coupling reactions. Many pretreatment methods have been developed to address recalcitrance, with ammonia pretreatments in general, and the AFEX (Ammonia Fiber Expansion) process in particular, among the more promising methods. In order to understand the polysaccharide liberating reactions involved in the cleavage of diferulate cell wall cross-links during AFEX pretreatment, reaction products from five esters modeling the major diferulates in grass cell walls treated under AFEX-like conditions were separated and characterized by NMR and HR-MS. Results from this study indicate that, beyond the anticipated amide products, a range of degradation products derive from an array of cleavage and substitution reactions, and reveal various pathways for incorporating ammonia-based nitrogen into biomass. PMID:21853208

  17. QUANTIFICATION OF AMMONIA, MMA, DMA, TMA AND TMAO IN FISH PROCESSING BY-PRODUCTS FROM DIFFERENT COLD WATER MARINE SPECIES BY CAPILLARY ELECTROPHORESIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Determinations of the total volatile base nitrogen (TVB-N) are routinely used to evaluate fish quality. TVB-N consists of ammonia, monomethylamine (MMA), dimethylamine (DMA), and trimethylamine (TMA), the levels of which are altered during spoilage by bacterial or enzymic degradation of trimethylami...

  18. Modeling of Chill Down in Cryogenic Transfer Lines

    NASA Technical Reports Server (NTRS)

    Cross, Matthew F.; Majumdar, Alok K.; Bennett, John C., Jr.; Malla, Ramesh B.; Rodriquez, Pete (Technical Monitor)

    2001-01-01

    A numerical model to predict chill down in cryogenic transfer lines has been developed. Three chill down cases using hydrogen as the working fluid are solved: 1) a simplified model amenable to analytical solution, 2) a realistic model of superheated vapor flow, and 3) a realistic model of initially subcooled liquid flow. The first case compares a numerical model with an analytical solution with very good agreement between the two. Additionally, the analytical solution provides a convenient way to look at parametric effects on the chill down. The second and third cases are numerical models which provide temperature histories of the fluid and solid tube wall during chill down as well as several other quantities of interest such as pressure and mass flow rate. Of great interest is the ability to predict accurate values of chill down time (the time required to achieve steady-state cryogenic flow). The models predict that a 26 in. long, 3/16 in. ID aluminum tube has a shorter chill down time (approx. equal to 100 sec) and uses less hydrogen with superheated vapor flow than with initially subcooled liquid flow (greater than 200 sec for chill down).

  19. The effects of blast chilling on pork quality.

    PubMed

    Rybarczyk, Artur; Karamucki, Tadeusz; Pietruszka, Arkadiusz; Rybak, Kinga; Matysiak, Beata

    2015-03-01

    The aim of this study was to determine the effects of blast chilling of pig carcasses on the physiochemical and sensory properties of the longissimus lumborum muscle. To this end, right half-carcasses were blast-chilled for 70min at -24°C and then for 22h and 50min at 1°C, while left half-carcasses were chilled conventionally at 1°C for 24h. At 2h and 6h post mortem, blast chilling had significantly reduced the temperature of the carcasses, as well as the rate of pH decrease and the rate of increase in EC. It had no significant effect on the ultimate pH or its range, or on EC at 24h post mortem, but it significantly lowered L*, b*, C* and drip loss compared to the conventionally chilled carcasses. Blast chilling adversely affected sensory characteristics such as tenderness and flavor. There were no significant differences between the effects of blast and conventional chilling systems on meat quality between conformation classes. PMID:25462383

  20. Ammonia emission time profiles based on manure transport data improve ammonia modelling across north western Europe

    NASA Astrophysics Data System (ADS)

    Hendriks, C.; Kranenburg, R.; Kuenen, J. J. P.; Van den Bril, B.; Verguts, V.; Schaap, M.

    2016-04-01

    Accurate modelling of mitigation measures for nitrogen deposition and secondary inorganic aerosol (SIA) episodes requires a detailed representation of emission patterns from agriculture. In this study the meteorological influence on the temporal variability of ammonia emissions from livestock housing and application of manure and fertilizer are included in the chemistry transport model LOTOS-EUROS. For manure application, manure transport data from Flanders (Belgium) were used as a proxy to derive the emission variability. Using improved ammonia emission variability strongly improves model performance for ammonia, mainly by a better representation of the spring maximum. The impact on model performance for SIA was negligible as explained by the limited, ammonia rich region in which the emission variability was updated. The contribution of Flemish agriculture to modelled annual mean ammonia and SIA concentrations in Flanders were quantified at respectively 7-8 and 1-2 μg/m3. A scenario study was performed to investigate the effects of reducing ammonia emissions from manure application during PM episodes by 75%, yielding a maximum reduction in modelled SIA levels of 1-3 μg/m3 during episodes. Year-to-year emission variability and a soil module to explicitly model the emission process from manure and fertilizer application are needed to further improve the modelling of the ammonia budget.

  1. Nitric oxide scavengers differentially inhibit ammonia oxidation in ammonia-oxidizing archaea and bacteria.

    PubMed

    Sauder, Laura A; Ross, Ashley A; Neufeld, Josh D

    2016-04-01

    Differential inhibitors are important for measuring the relative contributions of microbial groups, such as ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA), to biogeochemical processes in environmental samples. In particular, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO) represents a nitric oxide scavenger used for the specific inhibition of AOA, implicating nitric oxide as an intermediate of thaumarchaeotal ammonia oxidation. This study investigated four alternative nitric oxide scavengers for their ability to differentially inhibit AOA and AOB in comparison to PTIO. Caffeic acid, curcumin, methylene blue hydrate and trolox were tested onNitrosopumilus maritimus, two unpublished AOA representatives (AOA-6f and AOA-G6) as well as the AOB representativeNitrosomonas europaea All four scavengers inhibited ammonia oxidation by AOA at lower concentrations than for AOB. In particular, differential inhibition of AOA and AOB by caffeic acid (100 μM) and methylene blue hydrate (3 μM) was comparable to carboxy-PTIO (100 μM) in pure and enrichment culture incubations. However, when added to aquarium sponge biofilm microcosms, both scavengers were unable to inhibit ammonia oxidation consistently, likely due to degradation of the inhibitors themselves. This study provides evidence that a variety of nitric oxide scavengers result in differential inhibition of ammonia oxidation in AOA and AOB, and provides support to the proposed role of nitric oxide as a key intermediate in the thaumarchaeotal ammonia oxidation pathway. PMID:26946536

  2. Temperature-Induced Leakage from Chilling-Sensitive and Chilling-Resistant Plants 12

    PubMed Central

    Paull, Robert E.

    1981-01-01

    Leakage rates were determined from leaf cells loaded with rubidium and [3H]leucine. There was a differential response between leucine and rubidium leakage depending upon the species used. The rate of leucine leakage shows a small decline below 5 C for two altitudinal variants of Lycopersicon hirsutum Humb. and Bonpl., whereas Lycopersicon esculentum L. showed a marked increase below 5 C. Rubidium showed a marked increase in leakage rate below 10 C with the altitudinal variants, with only a slight increase for the L. esculentum species. A rough relationship existed between rubidium leakage rate at 1 C and the altitude of origin of the L. hirsutum race, the low altitudinal forms having higher leakage rates than the higher altitudinal variants. The L. esculentum lines show a rubidium leakage response similar to that of the high altitude L. hirsutum variants. Higher leakage rates were obtained if the calcium concentration in the medium was less than 1 millimolar and upon addition of metabolic poisons and detergents. The results are consistent with the view that chilling injury causes changes in the membrane and that cell leakage is an early symptom of this change in some species. Some chilling-sensitive species have increased leakage within 1 hour of exposure to chilling temperature. PMID:16661859

  3. Mechanics of buried chilled gas pipelines

    SciTech Connect

    Selvadurai, A.P.S.; Hu, J.

    1996-12-31

    This paper examines the factors influencing the modelling of soil-pipeline interaction for a pipeline which is used to transport chilled gas. The soil-pipeline interaction is induced by the generation of discontinuous frost heave at a boundary between soils with differing frost susceptibility. The three-dimensional modelling takes into consideration the time-dependent evolution of frost heave due to moisture migration, the creep and elastic behavior of the frozen soil and flexural behavior of the embedded pipeline. The results of the computational model are compared with experimental results obtained from the frost heave induced soil-pipeline interaction test performed at the full scale test facilities in Caen, France.

  4. Oxydesulfurization of a Turkish hard lignite with ammonia solutions

    SciTech Connect

    Yaman, S.; Kuecuekbayrak, S.

    1996-09-01

    In this study the desulfurization of a high pyritic and high organic sulfur lignite taken from the Gediz area (western Turkey) was investigated by the oxydesulfurization method using ammonia solutions. The influence of such parameters as the concentration of ammonia solution, partial pressure of oxygen, temperature, and reaction time were studied. The ranges of these parameters were selected as 0--10 M concentration of ammonia solution, 0--1.5 MPa partial pressure of oxygen, 403--473 K temperature, and 10--60 min reaction time. It was concluded that the use of ammonia solution as an extraction solution increased the efficiency of the oxydesulfurization process.

  5. Effects of chilling rate and spray-chilling on weight loss and tenderness in beef strip loin steaks.

    PubMed

    Prado, C S; de Felício, P E

    2010-10-01

    We evaluated the effects of chilling rate and the use of a spray-chilling system on the weight loss by evaporation on carcasses. We also evaluated the effects on meat purge in vacuum package, cooking losses, and on parameters related to the tenderness of strip loin steaks (M. longissimus lumborum). Forty non-castrated males of approximately 12 months old, finished in feed-lot were harvested in 16 Montana cattle (a composite breed), and 24 SimmentalxNellore crossbred cattle. After bleeding, the bodies were electrically stimulated and assigned to one of the four treatments: conventional air-chilling (CAC), conventional spray-chilling (CSC), slow air-chilling (SAC), and slow spray-chilling (SSC). Strip loin steaks (M. longissimus lumborum) of approximately 2.5 cm thick were removed, vacuum packed and aged for 7, 14, 30 or 60 days. Samples were analyzed for sarcomere length, myofibrillar fragmentation index, Warner-Bratzler shear force, and weight losses by purge and cooking. Spraying was efficient in reducing weight loss by evaporation (P<0.05). Effects of treatments and aging period on purge losses were observed, where samples from sprayed carcasses or aged cuts showed higher losses. Cooking losses were not affected either by spraying or aging. The slow chilling, with or without spraying, was more efficient in producing strip loin steaks with lower average shear force and longer sarcomere. The myofibrillar fragmentation index increased with aging time, but was not affected by carcasses spraying. PMID:20647150

  6. Sugar-driven prebiotic synthesis of ammonia from nitrite.

    PubMed

    Weber, Arthur L

    2010-06-01

    Reaction of 3-5 carbon sugars, glycolaldehyde, and alpha-ketoaldehydes with nitrite under mild anaerobic aqueous conditions yielded ammonia, an essential substrate for the synthesis of nitrogen-containing molecules during abiogenesis. Under the same conditions, ammonia synthesis was not driven by formaldehyde, glyoxylate, 2-deoxyribose, and glucose, a result indicating that the reduction process requires an organic reductant containing either an accessible alpha-hydroxycarbonyl group or an alpha-dicarbonyl group. Small amounts of aqueous Fe(+3) catalyzed the sugar-driven synthesis of ammonia. The glyceraldehyde concentration dependence of ammonia synthesis, and control studies of ammonia's reaction with glyceraldehyde, indicated that ammonia formation is accompanied by incorporation of part of the synthesized ammonia into sugar-derived organic products. The ability of sugars to drive the synthesis of ammonia is considered important to abiogenesis because it provides a way to generate photochemically unstable ammonia at sites of sugar-based origin-of-life processes from nitrite, a plausible prebiotic nitrogen species. PMID:20213158

  7. Comparative Transcriptome Profiling of Chilling Stress Responsiveness in Two Contrasting Rice Genotypes

    PubMed Central

    Zhang, Ting; Zhao, Xiuqin; Wang, Wensheng; Pan, Yajiao; Huang, Liyu; Liu, Xiaoyue; Zong, Ying; Zhu, Linghua; Yang, Daichang; Fu, Binying

    2012-01-01

    Rice is sensitive to chilling stress, especially at the seedling stage. To elucidate the molecular genetic mechanisms of chilling tolerance in rice, comprehensive gene expressions of two rice genotypes (chilling-tolerant LTH and chilling-sensitive IR29) with contrasting responses to chilling stress were comparatively analyzed. Results revealed a differential constitutive gene expression prior to stress and distinct global transcription reprogramming between the two rice genotypes under time-series chilling stress and subsequent recovery conditions. A set of genes with higher basal expression were identified in chilling-tolerant LTH compared with chilling-sensitive IR29, indicating their possible role in intrinsic tolerance to chilling stress. Under chilling stress, the major effect on gene expression was up-regulation in the chilling- tolerant genotype and strong repression in chilling-sensitive genotype. Early responses to chilling stress in both genotypes featured commonly up-regulated genes related to transcription regulation and signal transduction, while functional categories for late phase chilling regulated genes were diverse with a wide range of functional adaptations to continuous stress. Following the cessation of chilling treatments, there was quick and efficient reversion of gene expression in the chilling-tolerant genotype, while the chilling-sensitive genotype displayed considerably slower recovering capacity at the transcriptional level. In addition, the detection of differentially-regulated TF genes and enriched cis-elements demonstrated that multiple regulatory pathways, including CBF and MYBS3 regulons, were involved in chilling stress tolerance. A number of the chilling-regulated genes identified in this study were co-localized onto previously fine-mapped cold-tolerance-related QTLs, providing candidates for gene cloning and elucidation of molecular mechanisms responsible for chilling tolerance in rice. PMID:22912843

  8. Liberation of ammonia by cyanobacteria

    SciTech Connect

    Newton, J.W.

    1986-04-01

    Photoheterotrophic nitrogen-fixing cyanobacteria release ammonia when treated with methionine sulfoximine (MSX) to inhibit nitrogen incorporation into protein. This released ammonia can be derived from recently fixed nitrogen (nitrogen atmosphere) or endogenous reserves (argon atmosphere). Anaerobic ammonia release requires light and is stimulated by the photosystem II herbicides DCMU and Atrazine, regardless of the source of ammonia. As much as one quarter of the total cellular nitrogen can be released as ammonia by cyanbacteria treated with MSX and DCMU under argon in light. Chromatography of cell extracts indicates that virtually all cellular proteins are degraded. DCMU and Atrazine, at very low concentration, inhibit sustained uptake of the ammonia analog /sup 14/C methylamine. These data indicate that the herbicides interrupt ammonia uptake and retention by the cells, and support a role for photosystem II in ammonia metabolism.

  9. The Chemistry of Liquid Ammonia.

    ERIC Educational Resources Information Center

    Lagowski, J. J.

    1978-01-01

    The solvent and chemical properties of liquid ammonia are presented. In a certain sense, ammonia is a more versatile solvent than is water because of its ability to solubilize, without reaction, highly negative or reducing species. (Author/BB)

  10. Dissociation and Mass Transfer Coefficients for Ammonia Volatilization Models

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Process-based models are being used to predict ammonia emissions from manure sources, but their accuracy has not been fully evaluated for cattle manure. Laboratory trials were conducted to measure the dissociation and mass transfer coefficients for ammonia volatilization from media of buffered ammon...

  11. Electrolytic synthesis of ammonia in molten salts under atmospheric pressure.

    PubMed

    Murakami, Tsuyoshi; Nishikiori, Tokujiro; Nohira, Toshiyuki; Ito, Yasuhiko

    2003-01-15

    Ammonia was successfully synthesized by using a new electrochemical reaction with high current efficiency at atmospheric pressure and at lower temperatures than the Haber-Bosch process. In this method, nitride ion (N3-), which is produced by the reduction from nitrogen gas at the cathode, is anodically oxidized and reacts with hydrogen to produce ammonia at the anode. PMID:12517136

  12. Chemical additive to enhance antimicrobial efficacy of chlorine and control cross-contamination during immersion chill of broiler carcasses.

    PubMed

    Schambach, B T; Berrang, M E; Harrison, M A; Meinersmann, R J

    2014-09-01

    Immersion chilling of broiler carcasses can be a site for cross-contamination between the occasional highly contaminated carcass and those that are co-chilled. Chlorine is often used as an antimicrobial but can be overcome by organic material. A proprietary chlorine stabilizer (T-128) based on phosphoric acid-propylene glycol was tested as a chill tank additive in experiments simulating commercial broiler chilling. In bench-scale experiments, 0.5% T-128 was compared with plain water (control), 50 ppm of chlorine, and the combination of 0.5% T-128 with 50 ppm of chlorine to control transfer of Salmonella and Campylobacter from inoculated wing drummettes to co-chilled uninoculated drummettes. Both chlorine and T-128 lessened cross-contamination with Salmonella (P < 0.05); T-128 and T-128 with chlorine were significantly more effective (P < 0.05) than the control or plain chlorine for control of Campylobacter. T-128 treatments were noted to have a pH of less than 4.0; an additional experiment demonstrated that the antimicrobial effect of T-128 was not due merely to a lower pH. In commercial broiler chilling, a pH close to 6.0 is preferred to maximize chlorine effectiveness, while maintaining water-holding capacity of the meat. In a set of pilot-scale experiments with T-128, a near-ideal pH of 6.3 was achieved by using tap water instead of the distilled water used in bench-scale experiments. Pilot-scale chill tanks were used to compare the combination of 0.5% T-128 and 50 ppm of chlorine with 50 ppm of plain chlorine for control of cross-contamination between whole carcasses inoculated with Salmonella and Campylobacter and co-chilled uninoculated carcasses. The T-128 treatment resulted in significantly less crosscontamination by either direct contact or water transfer with both organisms compared with plain chlorine treatment. T-128 may have use in commercial broiler processing to enhance the effectiveness of chlorine in processing water. PMID:25198851

  13. The effect of chilling broiler carcasses in cold air or ice water on the population of Campylobacter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Broiler carcasses from a Campylobacter positive flock may remain contaminated with Campylobacter after processing. Most broiler companies in the U.S. use an ice water immersion method to bring carcasses down in temperature; air chilling of broiler carcasses is more common in Europe. The objective ...

  14. Chilling outweighs photoperiod in preventing precocious spring development.

    PubMed

    Laube, Julia; Sparks, Tim H; Estrella, Nicole; Höfler, Josef; Ankerst, Donna P; Menzel, Annette

    2014-01-01

    It is well known that increased spring temperatures cause earlier onset dates of leaf unfolding and flowering. However, a temperature increase in winter may be associated with delayed development when species' chilling requirements are not fulfilled. Furthermore, photosensitivity is supposed to interfere with temperature triggers. To date, neither the relative importance nor possible interactions of these three factors have been elucidated. In this study, we present a multispecies climate chamber experiment to test the effects of chilling and photoperiod on the spring phenology of 36 woody species. Several hypotheses regarding their variation with species traits (successional strategy, floristic status, climate of their native range) were tested. Long photoperiods advanced budburst for one-third of the studied species, but magnitudes of these effects were generally minor. In contrast to prior hypotheses, photosensitive responses were not restricted to climax or oceanic species. Increased chilling length advanced budburst for almost all species; its effect greatly exceeding that of photoperiod. Moreover, we suggest that photosensitivity and chilling effects have to be rigorously disentangled, as the response to photoperiod was restricted to individuals that had not been fully chilled. The results indicate that temperature requirements and successional strategy are linked, with climax species having higher chilling and forcing requirements than pioneer species. Temperature requirements of invasive species closely matched those of native species, suggesting that high phenological concordance is a prerequisite for successful establishment. Lack of chilling not only led to a considerable delay in budburst but also caused substantial changes in the chronological order of species' budburst. The results reveal that increased winter temperatures might impact forest ecosystems more than formerly assumed. Species with lower chilling requirements, such as pioneer or invasive

  15. Aquifer thermal energy storage costs with a seasonal chill source

    SciTech Connect

    Brown, D.R.

    1983-01-01

    The cost of energy supplied by an aquifer thermal energy storage (ATES) system from a seasonal chill source was investigated. Costs were estimated for point demand and residential development ATES systems using the computer code AQUASTOR. AQUASTOR was developed at PNL specifically for the economic analysis of ATES systems. In this analysis the cost effect of varying a wide range of technical and economic parameters was examined. Those parameters exhibiting a substantial influence on the costs of ATES delivered chill were: system size; well flow rate; transmission distance; source temperature; well depth; and cost of capital. The effects of each parameter are discussed. Two primary constraints of ATES chill systems are the extremely low energy density of the storage fluid and the prohibitive costs of lengthy pipelines for delivering chill to residential users. This economic analysis concludes that ATES-delivered chill will not be competitive for residential cooling applications. The otherwise marginal attractiveness of ATES chill systems vanishes under the extremely low load factors characteristic of residential cooling systems. (LCL)

  16. Ammonia tank failure

    SciTech Connect

    Sweat, M.E.

    1983-04-01

    An ammonia tank failure at Hawkeye Chemical of Clinton, Iowa is discussed. The tank was a double-wall, 27,000 metric-ton tank built in 1968 and commissioned in December 1969. The paper presented covers the cause of the failure, repair, and procedural changes made to prevent recurrence of the failure. (JMT)

  17. Effect of dry-air chilling on sensory descriptive profiles of cooked broiler breast meat deboned four hours after the initiation of chilling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Air chilled chicken products are gaining popularity in the USA. It has been claimed that air chilling (AC) results in improved tenderness and flavor of broiler meat compared with immersion chilling (IC). However, there is a lack of published sensory study results to support the claims. The objecti...

  18. Ammonia excretion in aquatic and terrestrial crabs.

    PubMed

    Weihrauch, Dirk; Morris, Steve; Towle, David W

    2004-12-01

    The excretory transport of toxic ammonia across epithelia is not fully understood. This review presents data combined with models of ammonia excretion derived from studies on decapod crabs, with a view to providing new impetus to investigation of this essential issue. The majority of crabs preserve ammonotely regardless of their habitat, which varies from extreme hypersaline to freshwater aquatic environments, and ranges from transient air exposure to obligate air breathing. Important components in the excretory process are the Na+/K+(NH4+)-ATPase and other membrane-bound transport proteins identified in many species, an exocytotic ammonia excretion mechanism thought to function in gills of aquatic crabs such as Carcinus maenas, and gaseous ammonia release found in terrestrial crabs, such as Geograpsus grayi and Ocypode quadrata. In addition, this review presents evidence for a crustacean Rhesus-like protein that shows high homology to the human Rhesus-like ammonia transporter both in its amino acid sequence and in its predicted secondary structure. PMID:15579545

  19. Developmental stages of cultivated strawberry flowers in relation to chilling sensitivity

    PubMed Central

    Ariza, Maria Teresa; Soria, Carmen; Martínez-Ferri, Elsa

    2015-01-01

    Environmental factors affecting flower development may limit the yields of fruiting crops worldwide. In temperate regions, chilling temperatures during flower development can compromise fruit production, but their negative effects vary depending on the differing susceptibilities of each developmental stage. The cultivated strawberry (Fragaria× ananassa Duch.) is widely grown worldwide but financial returns are influenced by sudden shifts to chilling temperatures occurring during the cropping cycle. Despite this important limitation, knowledge of F.× ananassa flower development is lacking, in contrast to the diploid wild-type strawberry (F. vesca). In this study we describe steps in floral development of cultivated strawberry and define their vulnerability to chilling temperatures. To achieve this, flower buds from strawberry plants of cv. ‘Camarosa’ were labelled and monitored from bud initiation until anthesis. Description of morphological and functional changes during flower development was based on histological sections and scanning electron microscopy. To determine the impact of low temperatures at different developmental stages, plants carrying buds of different sizes were chilled at 2 °C for 24 h. Several parameters related to male and female gametophyte development were later evaluated in flowers as they approached anthesis. Fragaria× ananassa flower development was divided into 16 stages according to landmark events. These stages were similar to those documented for F. vesca but three new additional intermediate stages were described. Timing of developmental processes was achieved by correlating developmental staging with specific bud sizes and days before anthesis. Time to reach anthesis from early bud stages was 17–18 days. During this period, we detected four critical periods vulnerable to low temperatures. These were mostly related to male gametophyte development but also to injury to female organs at late developmental stages. These results

  20. Developmental stages of cultivated strawberry flowers in relation to chilling sensitivity.

    PubMed

    Ariza, Maria Teresa; Soria, Carmen; Martínez-Ferri, Elsa

    2015-01-01

    Environmental factors affecting flower development may limit the yields of fruiting crops worldwide. In temperate regions, chilling temperatures during flower development can compromise fruit production, but their negative effects vary depending on the differing susceptibilities of each developmental stage. The cultivated strawberry (Fragaria× ananassa Duch.) is widely grown worldwide but financial returns are influenced by sudden shifts to chilling temperatures occurring during the cropping cycle. Despite this important limitation, knowledge of F.× ananassa flower development is lacking, in contrast to the diploid wild-type strawberry (F. vesca). In this study we describe steps in floral development of cultivated strawberry and define their vulnerability to chilling temperatures. To achieve this, flower buds from strawberry plants of cv. 'Camarosa' were labelled and monitored from bud initiation until anthesis. Description of morphological and functional changes during flower development was based on histological sections and scanning electron microscopy. To determine the impact of low temperatures at different developmental stages, plants carrying buds of different sizes were chilled at 2 °C for 24 h. Several parameters related to male and female gametophyte development were later evaluated in flowers as they approached anthesis. Fragaria× ananassa flower development was divided into 16 stages according to landmark events. These stages were similar to those documented for F. vesca but three new additional intermediate stages were described. Timing of developmental processes was achieved by correlating developmental staging with specific bud sizes and days before anthesis. Time to reach anthesis from early bud stages was 17-18 days. During this period, we detected four critical periods vulnerable to low temperatures. These were mostly related to male gametophyte development but also to injury to female organs at late developmental stages. These results provide

  1. Prevalence and Serogroup Diversity of Salmonella for Broiler Neck Skin, Whole Carcass Rinse, and Whole Carcass Enrichment Sampling Methodologies following Air or Immersion Chilling.

    PubMed

    Bourassa, D V; Holmes, J M; Cason, J A; Cox, N A; Rigsby, L L; Buhr, R J

    2015-11-01

    The purpose of this study was to evaluate neck skin (NS), whole carcass rinse (WCR), and whole carcass enrichment (WCE) sampling procedures for Salmonella isolation and serogroup identification from the same broiler chicken carcass treated with air or immersion chilling. Commercially processed and eviscerated broiler carcasses were collected from a commercial processing plant, individually bagged, and transported to the pilot processing plant. In experiment 1, carcasses were air chilled to 4°C. In experiment 2, carcasses were immersion chilled with or without chlorine. After air chilling, Salmonella was detected on 78% of NS and 89% of WCE samples. Only one Salmonella serogroup was detected from each of 13 Salmonella-positive NS samples, and two serogroups were detected on 1 Salmonella-positive NS sample. Only one Salmonella serogroup was detected from each of 13 Salmonella-positive WCE samples, and two serogroups were detected from 3 Salmonella-positive WCE samples. After immersion chilling without chlorine, Salmonella was detected on 38% of NS, 45% of WCR, and 100% of WCE samples. Without chlorine, the 15 Salmonella-positive NS samples included 14 samples with one serogroup and 1 sample with two serogroups. Only one Salmonella serogroup was detected from WCR samples after immersion chilling. Of 40 Salmonella-positive WCE samples, 23 had a one, 14 had two, and 3 had three Salmonella serogroups. After immersion chilling with chlorine, Salmonella was detected on 35% of NS, 0% of WCR, and 90% of WCE samples. With chlorine, the 14 Salmonella-positive NS samples included 11 samples with one serogroup and 3 samples with two serogroups. No Salmonella serogroups were detected from WCR samples after immersion chilling with 20 mg/liter free chlorine. The 36 Salmonella-positive WCE samples included 21 samples with one serogroup and 15 samples with two serogroups. NS and WCE sampling methodologies yielded similar prevalence and serogroup diversity after air chilling. However

  2. Sugar-Driven Prebiotic Synthesis of Ammonia from Nitrite

    NASA Astrophysics Data System (ADS)

    Weber, Arthur L.

    2010-03-01

    Reaction of 3-5 carbon sugars, glycolaldehyde, and α-ketoaldehydes with nitrite under mild anaerobic aqueous conditions yielded ammonia, an essential substrate for the synthesis of nitrogen-containing molecules during abiogenesis. Under the same conditions, ammonia synthesis was not driven by formaldehyde, glyoxylate, 2-deoxyribose, and glucose, a result indicating that the reduction process requires an organic reductant containing either an accessible α-hydroxycarbonyl group or an α-dicarbonyl group. Small amounts of aqueous Fe+3 catalyzed the sugar-driven synthesis of ammonia. The glyceraldehyde concentration dependence of ammonia synthesis, and control studies of ammonia’s reaction with glyceraldehyde, indicated that ammonia formation is accompanied by incorporation of part of the synthesized ammonia into sugar-derived organic products. The ability of sugars to drive the synthesis of ammonia is considered important to abiogenesis because it provides a way to generate photochemically unstable ammonia at sites of sugar-based origin-of-life processes from nitrite, a plausible prebiotic nitrogen species.

  3. Synthesis of chemically-modified single-walled carbon nanotubes by counter-current ammonia gas injection into the induction thermal plasma process

    NASA Astrophysics Data System (ADS)

    Shahverdi, Ali

    Pristine single-walled carbon nanotubes (SWCNTs) are poorly dispersible and insoluble in many solvents and need to be chemically modified prior to their use in many applications. This work is focused on the investigation of the synthesis of chemically modified SWCNTs material through an in situ approach. The main objectives of the presented research are: 1) to explore the in situ chemical process during the synthesis of SWCNT and 2) to closely examine the effect of a reactive environment on SWCNTs. Effects of the catalyst type and content on the SWCNTs final product, synthesized by induction thermal plasma (ITP), were studied to replace toxic cobalt (Co) in the feedstock. In this regard, three different catalyst mixtures (i.e. Ni-Y2O3, Ni-Co-Y2O3, and Ni-Mo-Y2O3) were used. Experimental results showed that the catalyst type affects the quality of the SWCNT final product. Similar quality SWCNTs can be produced when the same amount of Co was replaced by Ni. Moreover, the results observed in this experimental work were further explained by thermodynamic calculation results. Thermogravimetry (TG) was used throughout the work to characterize the SWCNTs product. TG was firstly standardized by studying the effects of three main instrumental parameters (temperature ramp, TR, initial mass of the sample, IM, and gas flow rate, FR) on the Tonset and full-width half maximum (FWHM) obtained from TG and derivative TG graphs of carbon black, respectively. Therefore, a two-level factorial statistical design was performed. The statistical analysis showed that the effect of TR, IM, and to a lower extent, FR, is significant on FWHM and insignificant on Tonset. A methodology was then developed based upon the SWCNTs synthesis using the ITP system, through an in situ chemistry approach. Ammonia (NH3) was selected and counter-currently injected into the ITP reactor at three different flow rates and by four different nozzle designs. Numerical simulation indicated a better mixing of NH3 in

  4. Tomato expressing Arabidopsis glutaredoxin gene AtGRXS17 confers tolerance to chilling stress via modulating cold responsive components

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chilling stress is a production constraint of tomato, a tropical origin, chilling-sensitive horticultural crop. The development of chilling tolerant tomato thus has significant potential to impact tomato production. Glutaredoxins (GRXs) are ubiquitous oxidoreductases, which utilize the reducing powe...

  5. Oceanic emissions of ammonia

    NASA Astrophysics Data System (ADS)

    Paulot, F.; Jacob, D. J.; Johnson, M.; Bell, T. G.; Stock, C. A.; Doney, S. C.

    2013-12-01

    Half of natural ammonia (NH3) emissions is thought to originate from the oceans. Such large emissions have implications for the global budget of N and the acidity of marine aerosols. We develop two new inventories of oceanic NH3 emissions based on simulated monthly NH3 seawater concentrations from the GFDL-COBALT and the CESM-BEC ocean models. These new inventories explicitly account for the effect of temperature on the water-atmosphere exchange of NH3. We evaluate these inventory using cruise observations of gas-phase ammonia (AMT cruises) and ammonium (NOAA cruises) as well as seawater measurement of NHx. Implications of atmospheric NHx observations for the exchange of N between ocean and land and ocean N/P limitations are discussed.

  6. Ammonia scrubbing makes alternative fuels economical

    SciTech Connect

    Brown, G.N.

    1997-09-01

    The first commercial in-situ forced oxidation ammonia scrubber system developed and patented by GE Environmental Systems (GEESI) has been completed at the Dakota Gasification Company`s Great Plains Synfuels Plant near Beulah, North Dakota, US. The process simultaneously removes acid gases while producing a valuable byproduct. It was developed to eliminate the performance issues associated with first generation ammonia scrubbing systems. In contrast to the ever increasing cost of lower sulfur fuels, the increasing levels of sulfur in the fuel can represent a greater economic benefit to the utility by burning a lower cost fuel coupled with production of a high value by-product. The sale of the by-product ammonium sulfate off-sets most of the scrubber capital and operating costs and in some cases can generate revenue. In this paper, the 300 MW commercial ammonium sulfate process installed in North Dakota is described. The initial operation is discussed. The ammonia scrubbing system economics and materials selections is presented. The ammonia scrubbing process economics for application using various fuels is presented.

  7. Comparative Transcriptomics of Sijung and Jumli Marshi Rice during Early Chilling Stress Imply Multiple Protective Mechanisms

    PubMed Central

    Lindlöf, Angelica; Chawade, Aakash; Sikora, Per; Olsson, Olof

    2015-01-01

    Introduction Low temperature is one of the major environmental factors that adversely affect plant growth and yield. Many cereal crops from tropical regions, such as rice, are chilling sensitive and, therefore, are affected already at <10°C. Interestingly, it has been demonstrated that chilling susceptibility varies greatly among rice varieties, which indicates differences in the underlying molecular responses. Understanding these differences is vital for continued development of rational breeding and transgenic strategies for more tolerant varieties. Thus, in this study, we conducted a comparative global gene expression profiling analysis of the chilling tolerant varieties Sijung and Jumli Marshi (spp. Japonica) during early chilling stress (<24 h, 10°C). Methods and Results Global gene expression experiments were conducted with Agilent Rice Gene Expression Microarray 4x44K. The analysed results showed that there was a relatively low (percentage or number) overlap in differentially expressed genes in the two varieties and that substantially more genes were up-regulated in Jumli Marshi than in Sijung but the number of down-regulated genes were higher in Sijung. In broad GO annotation terms, the activated response pathways in Sijung and Jumli Marshi were coherent, as a majority of the genes belonged to the catalytic, transcription regulator or transporter activity categories. However, a more detailed analysis revealed essential differences. For example, in Sijung, activation of calcium and phosphorylation signaling pathways, as well as of lipid transporters and exocytosis-related proteins take place very early in the stress response. Such responses can be coupled to processes aimed at strengthening the cell wall and plasma membrane against disruption. On the contrary, in Jumli Marshi, sugar production, detoxification, ROS scavenging, protection of chloroplast translation, and plausibly the activation of the jasmonic acid pathway were the very first response

  8. Industrial ammonia gassing

    PubMed Central

    Walton, M.

    1973-01-01

    Walton, M. (1972).British Journal of Industrial Medicine,30, 78-86. Industrial ammonia gassing. Seven cases of ammonia gassing are described with follow-up for five years of the six survivors and the post-mortem findings of the fatal case. All the survivors attributed continuing symptoms to the gassing. The study failed to demonstrate permanent ill effects in the one case of mild exposure. Of the more serious cases one has stopped smoking and taken up physical training teaching. He now has above average lung function. Two serious cases who continued to smoke have the lung function abnormalities expected from their smoking. In the other two seriously exposed cases, who also continued to smoke, there is a persistent reduction in ventilation and gas transfer which seems to be due to the ammonia gassing. The post-mortem findings in the fatal case showed acute congestion and oedema of the mucosa of the respiratory tract, the bronchial walls being stripped of their lining epithelium and the alveoli stuffed with red blood cells and oedema fluid. Images PMID:4685304

  9. Alkaline Ammonia Electrolysis on Electrodeposited Platinum for Controllable Hydrogen Production.

    PubMed

    Gwak, Jieun; Choun, Myounghoon; Lee, Jaeyoung

    2016-02-19

    Ammonia is beginning to attract a great deal of attention as an alternative energy source carrier, because clean hydrogen can be produced through electrolytic processes without the emission of COx . In this study, we deposited various shapes of Pt catalysts under potentiostatic mode; the electrocatalytic oxidation behavior of ammonia using these catalysts was studied in alkaline media. The electrodeposited Pt was characterized by both qualitative and quantitative analysis. To discover the optimal structure and the effect of ammonia concentration, the bulk pH value, reaction temperature, and applied current of ammonia oxidation were investigated using potential sweep and galvanostatic methods. Finally, ammonia electrolysis was conducted using a zero-gap cell, producing highly pure hydrogen with an energy efficiency over 80 %. PMID:26530809

  10. A simple route to vertical array of quasi-1D ZnO nanofilms on FTO surfaces: 1D-crystal growth of nanoseeds under ammonia-assisted hydrolysis process

    PubMed Central

    2011-01-01

    A simple method for the synthesis of ZnO nanofilms composed of vertical array of quasi-1D ZnO nanostructures (quasi-NRs) on the surface was demonstrated via a 1D crystal growth of the attached nanoseeds under a rapid hydrolysis process of zinc salts in the presence of ammonia at room temperature. In a typical procedure, by simply controlling the concentration of zinc acetate and ammonia in the reaction, a high density of vertically oriented nanorod-like morphology could be successfully obtained in a relatively short growth period (approximately 4 to 5 min) and at a room-temperature process. The average diameter and the length of the nanostructures are approximately 30 and 110 nm, respectively. The as-prepared quasi-NRs products were pure ZnO phase in nature without the presence of any zinc complexes as confirmed by the XRD characterisation. Room-temperature optical absorption spectroscopy exhibits the presence of two separate excitonic characters inferring that the as-prepared ZnO quasi-NRs are high-crystallinity properties in nature. The mechanism of growth for the ZnO quasi-NRs will be proposed. Due to their simplicity, the method should become a potential alternative for a rapid and cost-effective preparation of high-quality ZnO quasi-NRs nanofilms for use in photovoltaic or photocatalytics applications. PACS: 81.07.Bc; 81.16.-c; 81.07.Gf. PMID:22027275

  11. Concurrent effects of cold and hyperkalaemia cause insect chilling injury.

    PubMed

    MacMillan, Heath A; Baatrup, Erik; Overgaard, Johannes

    2015-10-22

    Chilling injury and death are the ultimate consequence of low temperature exposure for chill susceptible insects, and low temperature tolerance is considered one of the most important factors determining insect distribution patterns. The physiological mechanisms that cause chilling injury are unknown, but chronic cold exposure that causes injury is consistently associated with elevated extracellular [K(+)], and cold tolerant insects possess a greater capacity to maintain ion balance at low temperatures. Here, we use the muscle tissue of the migratory locust (Locusta migratoria) to examine whether chill injury occurs during cold exposure or following return to benign temperature and we specifically examine if elevated extracellular [K(+)], low temperature, or a combination thereof causes cell death. We find that in vivo chill injury occurs during the cold exposure (when extracellular [K(+)] is high) and that there is limited capacity for repair immediately following the cold stress. Further, we demonstrate that that high extracellular [K(+)] causes cell death in situ, but only when experienced at low temperatures. These findings strongly suggest that that the ability to maintain ion (particularly K(+)) balance is critical to insect low temperature survival, and highlight novel routes of study in the mechanisms regulating cell death in insects in the cold. PMID:26468241

  12. Delayed light emission and fluorescence responses of plants to chilling

    SciTech Connect

    Abbott, J.A.; Campbell, T.A.; Massie, D.R. . Agricultural Research Service)

    1994-01-01

    Delayed light emission (DLE) of chlorophyll has the same excitation and emission spectra as chlorophyll fluorescence and was formerly called delayed fluorescence. DLE has a much longer time response than true chlorophyll fluorescence and is detectable for times ranging from milliseconds to many minutes. DLE is induced by back reactions of the photosynthetic pathway and therefore requires functional chloroplasts. It is detectable only in the dark following light excitation, yields very low energy, and decays very rapidly. DLE repetitively excited over time, which they term refreshed DLE (RDLE), shows a shoulder and broad peak in the measurements, indicating participation of at least two energy pools. DLE is altered by physiological stresses that affect chloroplasts or photosynthesis, and as illustration, plant species known to be very susceptible or very tolerant to chilling were exposed to chilling temperatures for varying times. RDLE at 0.3 s (the initial shoulder on the curves) rose in response to chilling damage in the susceptible species. The major RDLE peak was greatly inhibited in the susceptible species and showed only small changes in the tolerant species. Fluorescence measurements made on the chilling-tolerant species indicated similar responses and similar coefficients of determination were derived. These results indicate that measurement of precisely timed delayed light emission or of refreshed delayed light emission at a less precisely controlled time can be used to detect chilling stress.

  13. Impact of future warming on winter chilling in Australia.

    PubMed

    Darbyshire, Rebecca; Webb, Leanne; Goodwin, Ian; Barlow, E W R

    2013-05-01

    Increases in temperature as a result of anthropogenically generated greenhouse gas (GHG) emissions are likely to impact key aspects of horticultural production. The potential effect of higher temperatures on fruit and nut trees' ability to break winter dormancy, which requires exposure to winter chilling temperatures, was considered. Three chill models (the 0-7.2°C, Modified Utah, and Dynamic models) were used to investigate changes in chill accumulation at 13 sites across Australia according to localised temperature change related to 1, 2 and 3°C increases in global average temperatures. This methodology avoids reliance on outcomes of future GHG emission pathways, which vary and are likely to change. Regional impacts and rates of decline in chilling differ among the chill models, with the 0-7.2°C model indicating the greatest reduction and the Dynamic model the slowest rate of decline. Elevated and high latitude eastern Australian sites were the least affected while the three more maritime, less elevated Western Australian locations were shown to bear the greatest impact from future warming. PMID:22674019

  14. GLUTAMINE AS A MEDIATOR OF AMMONIA NEUROTOXICITY: A CRITICAL APPRAISAL

    PubMed Central

    Albrecht, Jan; Zielińska, Magdalena; Norenberg, Michael D.

    2010-01-01

    Ammonia is a major neurotoxin implicated in hepatic encephalopathy (HE). Here we discuss evidence that many aspects of ammonia toxicity in HE-affected brain are mediated by glutamine (Gln), synthesized in excess from ammonia and glutamate by glutamine synthetase (GS), an astrocytic enzyme. The degree to which Gln is increased in brains of patients with HE was found to positively correlate with the grade of HE. In animals with HE, a GS inhibitor, methionine sulfoximine (MSO), reversed a spectrum of manifestations of ammonia toxicity, including brain edema and increased intracranial pressure, even though MSO itself increased brain ammonia levels. MSO inhibited, while incubation with Gln reproduced the oxidative stress and cell swelling observed in ammonia-exposed cultured astrocytes. Recent studies have shown that astrocytes swell subsequent to Gln transport into mitochondria and its degradation back to ammonia, which then generates reactive oxygen species and the mitochondrial permeability transition. This sequence of events led to the formulation of the “Trojan Horse” hypothesis. Further verification of the role of Gln in the pathogenesis of HE will have to account for: 1) modification of the effects of Gln by interaction of astrocytes with other CNS cells; and 2) direct effects of Gln on these cells. Recent studies have demonstrated a “Trojan Horse”-like effect of Gln in microglia, as well as an interference by Gln with the activation of the NMDA/NO/cGMP pathway by ammonia as measured in whole brain, a process that likely also involves neurons. PMID:20654582

  15. Atmospheric dispersion of ammonia: an ammonia fog model

    SciTech Connect

    Kansa, E.J.; Rodean, H.C.; Chan, S.T.; Ermak, D.L.

    1983-01-01

    A simplification to the two-phase ammonia vapor-droplet fog problem has been implemented to study the dispersion of a spill of 40 tons of ammonia. We have circumvented the necessity of adding the partial differential equations for mass, momentum, and energy for the ammonia in the liquid phase by certain assumptions. It is assumed that the ammonia fog behaves as an ideal gas including the droplets. A temperature-dependent molecular weight was introduced to simulate the transition from a vapor-droplet cloud to a pure vapor cloud of ammonia. Likewise, the vaporization of ammonia was spread out over a temperature range. Mass, momentum, energy, and total ammonia is conserved rigorously. The observed features of the ammonia spill simulation have pointed out phenomena that could not be predicted in simpler calculations. Perhaps the most obvious feature is the cloud bifurcation due to the strength of the gravity current relative to the ambient wind. The gravity spreading of the denser ammonia fog significantly perturbs the unidirectional windfield in the vicinity of the spill, setting up complex eddy patterns in the cloud which are enhanced by ground heating and warm dry air entrainment. The lower concentrations appear to lift off by a buoyancy-induced flow. The ammonia cloud, rather than being cigar shaped as assumed in simpler models, ranges from pancake shaped to pear shaped, depending upon the ambient windfield. The fact that the ammonia cloud remains cold, very low, and wide is in qualitative agreement with some of the large-scale ammonia spill accidents. 14 figures.

  16. Ammonia scrubbing makes high sulfur fuels economical

    SciTech Connect

    Brown, G.N.

    1998-04-01

    The first commercial insitu forced oxidation ammonia scrubber system developed by Marsulex Environmental Technologies (MET), formerly GE Environmental Systems (GEESI), was completed at the Dakota Gasification Company`s Great Plains Synfuels Plant near Beulah, North Dakota, USA. The patented MET ammonia scrubbing system simultaneously removes acid gases while producing a high value byproduct, ammonium sulfate. The MET process was developed to eliminate performance issues associated with first generation ammonia scrubbing systems by unique application of standard, proven FGD equipment. The MET ammonia scrubbing process is particularly attractive for application on units which can reduce power generating costs by firing high sulfur content fuels. In contrast to the ever increasing cost of lower sulfur fuels, the increasing levels of sulfur in the fuel can represent a greater economic benefit to the utility by burning a lower cost fuel, coupled with production of a high value byproduct. The sale of the byproduct, ammonium sulfate, offsets most of the scrubber capital and operating costs and, in some cases, can generate revenue for the utility. This, in combination with the increasing need to replenish depleted sulfur from soil, makes production of ammonium sulfate an ideal product for sale in the agricultural market. In this paper, the 300 MW commercial ammonium sulfate process installed in North Dakota is described. The results of initial operation and testing are discussed. Current photos that illustrate the unique equipment and materials selection are presented. The ammonia scrubbing process economics for application using various sulfur fuels are compared. An economic comparison, in $/mmBTU, which incorporates reduced high sulfur fuel cost and the life cycle economics of the air pollution control system is also presented.

  17. Ammonia scrubbing makes high sulfur fuels economical

    SciTech Connect

    Brown, G.N.

    1998-07-01

    The first commercial in situ forced oxidation ammonia scrubber system developed by marsulex Environmental Technologies (MET), formerly GE Environmental Systems (GEESI), was completed at the Dakota Gasification Company's Great Plains Synfuels Plant near Beulah, North Dakota, USA. The patented MET ammonia scrubbing system simultaneously removes acid gases while producing a high value byproduct, ammonium sulfate. The MET process was developed to eliminate performance issues associated with first generation ammonia scrubbing systems by unique application of standard, proven FGD equipment. The MET ammonia scrubbing process is particularly attractive for application on units which can reduce power generating costs by firing high sulfur content fuels. In contrast to the ever increasing cost of lower sulfur fuels, the increasing levels of sulfur in the fuel can represent a greater economic benefit to the utility by burning a lower cost fuel, coupled with production of a high value byproduct. The sale of the byproduct, ammonium sulfate, offsets most of the scrubber capital and operating costs and, in some cases, can generate revenue for the utility. This, in combination with the increasing need to replenish depleted sulfur from soil, makes production of ammonium sulfate an ideal product for sale in the agricultural market. In this paper, the 300 MW commercial ammonium sulfate process installed in North Dakota is described. The results of initial operation and testing are discussed. Current photos that illustrate the unique equipment and materials selection are presented. The ammonia scrubbing process economics for application using various sulfur fuels are compared. An economic comparison, in $/mmBTU, which incorporates reduced high sulfur fuel cost and the life cycle economics of the air pollution control system is also presented.

  18. Ammonia synthesis. Ammonia synthesis by N₂ and steam electrolysis in molten hydroxide suspensions of nanoscale Fe₂O₃.

    PubMed

    Licht, Stuart; Cui, Baochen; Wang, Baohui; Li, Fang-Fang; Lau, Jason; Liu, Shuzhi

    2014-08-01

    The Haber-Bosch process to produce ammonia for fertilizer currently relies on carbon-intensive steam reforming of methane as a hydrogen source. We present an electrochemical pathway in which ammonia is produced by electrolysis of air and steam in a molten hydroxide suspension of nano-Fe2O3. At 200°C in an electrolyte with a molar ratio of 0.5 NaOH/0.5 KOH, ammonia is produced at 1.2 volts (V) under 2 milliamperes per centimeter squared (mA cm(-2)) of applied current at coulombic efficiency of 35% (35% of the applied current results in the six-electron conversion of N2 and water to ammonia, and excess H2 is cogenerated with the ammonia). At 250°C and 25 bar of steam pressure, the electrolysis voltage necessary for 2 mA cm(-2) current density decreased to 1.0 V. PMID:25104378

  19. Modeling of ingot development during the start-up phase of direct chill casting

    NASA Astrophysics Data System (ADS)

    Williams, A. J.; Croft, T. N.; Cross, M.

    2003-10-01

    Direct chill (DC) casting is a core primary process in the production of aluminum ingots. However, its operational optimization is still under investigation with regard to a number of features, one of which is the issue of curvature at the base of the ingot. Analysis of these features requires a computational model of the process that accounts for the fluid flow, heat transfer, solidification phase change, and thermomechanical anlaysis. This article describes an integrated approach to the modeling of all the preceding phenomena and their interactions

  20. Ammonia emissions from seabird colonies

    NASA Astrophysics Data System (ADS)

    Blackall, Trevor D.; Wilson, Linda J.; Theobald, Mark R.; Milford, Celia; Nemitz, Eiko; Bull, Jennifer; Bacon, Philip J.; Hamer, Keith C.; Wanless, Sarah; Sutton, Mark A.

    2007-05-01

    Ammonia emissions were measured from two entire seabird colonies with contrasting species assemblages, to ascertain the ammonia volatilisation potentials among seabird species in relation to their nesting behaviour. Emissions were calculated from downwind plume measurements of ammonia concentration using both inverse dispersion and tracer ratio methods. Measured colony emissions ranged 1-90 kg NH3 hour-1, and equated to 16 and 36% volatilization of excreted nitrogen for colonies dominated by ground/burrow nesting and bare rock nesting birds, respectively. The results were applied in a bioenergetics model with a global seabird database. Seabird colonies are found to represent the largest point sources of ammonia globally (up to ~6 Gg NH3 colony-1 year-1). Moreover the largest emissions occur mainly in remote environments with otherwise low NH3 emissions. These ammonia ``hot spots'' explain significant perturbations of the nitrogen cycle in these regions and add ~20% to oceanic ammonia emissions south of latitude 45°S.

  1. 36. JL photographer, summer 1978, general view of experimental ammonia ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. JL photographer, summer 1978, general view of experimental ammonia chlorine process equipment from ca 1930's at Baldwin Filtration Plant. - Division Avenue Pumping Station & Filtration Plant, West 45th Street and Division Avenue, Cleveland, Cuyahoga County, OH

  2. Development of Vapor-Phase Catalytic Ammonia Removal System

    NASA Technical Reports Server (NTRS)

    Flynn, Michael; Fisher, John; Kiss, Mark; Borchers, Bruce; Tleimat, Badawi; Tleimat, Maher; Quinn, Gregory; Fort, James; Nalette, Tim; Baker, Gale; Genovese, Joseph

    2007-01-01

    A report describes recent accomplishments of a continuing effort to develop the vapor-phase catalytic ammonia removal (VPCAR) process for recycling wastewater for consumption by humans aboard a spacecraft in transit to Mars.

  3. Chill sensitivity of honey bee, Apis mellifera, embryos.

    PubMed

    Collins, Anita M; Mazur, Peter

    2006-08-01

    Improved methods for preservation of honey bee, Apis mellifera L., germplasm would be very welcome to beekeeping industry queen breeders. The introduction of two parasites and the emergence of an antibiotic resistant disease have increased demands for resistant stock. Techniques for artificial insemination of queens are available, and semen has been cryopreserved with limited success. However, cryopreservation of embryos for rearing queens would mesh well with current practices and also provide drones (haploid males). Eggs at five ages between twenty-four hours and sixty-two hours were exposed to 0, -6.6, and/or -15 degrees C for various times, and successful hatch measured. Honey bee embryos show chill sensitivity as do other insect embryos, and the rate of chill injury increases dramatically with decrease in holding temperature. The 48 h embryos in both groups showed the greatest tolerance to chilling, although 44 h embryos were only slightly less so. PMID:16677625

  4. Improved Humidity Sensing with the Chilled Mirror: Really?

    NASA Technical Reports Server (NTRS)

    Schmidlin, Francis J.; Zukor, Dorothy (Technical Monitor)

    2001-01-01

    Testing of the chilled mirror sensor was initiated at Wallops Island in 1997. The chilled mirror dew point system is integrated with the Sippican, Inc., MK2 radiosonde providing a relatively inexpensive instrument. Early tests suggested that better stratospheric humidity measurements might be available. But, recent tests with different configurations of the mirror's cooler indicated that the systems capability to cool to the very low dew point temperatures required in the stratosphere were not being met with the present system. Nonetheless, the present mirror technology, while still undergoing development gives better humidity information between 400 and 100 hPa than the current routine radiosonde sensor. Comparisons are given of the chilled mirror and the typical operational humidity sensors.

  5. Sol-gel process for preparation of YBa{sub 2}Cu{sub 4}O{sub 8} from acidic acetates/ammonia/ascorbic acid systems

    SciTech Connect

    Deptula, A.; Lada, W.; Olczak, T.; Goretta, K.C.; Bartolomeo, A.; Casadio, S.

    1997-03-01

    YBa{sub 2}Cu{sub 4}O{sub x} sols were prepared by addition of ammonia to acidic acetate solutions of Y{sup 3+}, Ba{sup 2+}, and Cu{sup 2+}. Ascorbic acid was added to part of the sol. The resultant sols were gelled to a shard or a coating by evaporation at 60 C. Addition of ethanol to the sols facilitated formation of gel coatings, fabricated by a dipping technique, on Ag or glass or substrates. At 100 C, gels formed in the presence of ascorbic acid were perfectly amorphous, in contrast to crystalline acetate gels. The quality of coatings prepared from ascorbate gels was superior to that of acetate gel coatings.

  6. Revised Wind Chill Index (The Development of a New Wind Chill Temperature Chart)

    SciTech Connect

    Bluestein, Maurice

    2009-04-10

    It had been known for many years that the original wind chill temperature charts used by the weather services of Canada and the U.S. were flawed. This speaker applied modern heat transfer principles to the Antarctic research that was the basis for the original charts to demonstrate that the temperatures were much too cold. He then proposed an alternative model that would more accurately depict the effect of wind in cold weather on exposed skin. Media attention and an internet conference sponsored in Canada prompted the U.S. Weather Service to initiate a program to update their charts. This speaker and a Canadian researcher who worked with a similar approach were charged with developing a new chart. An algorithm was completed and the new chart was put into effect in Canada in October and in the U.S. in November, 2001.

  7. Revised Wind Chill Index (The Development of a New Wind Chill Temperature Chart)

    SciTech Connect

    Bluestein, Maurice

    2002-04-10

    It had been known for many years that the original wind chill temperature charts used by the weather services of Canada and the U.S. were flawed. This speaker applied modern heat transfer principles to the Antarctic research that was the basis for the original charts to demonstrate that the temperatures were much too cold. He then proposed an alternative model that would more accurately depict the effect of wind in cold weather on exposed skin. Media attention and an internet conference sponsored in Canada prompted the U.S. Weather Service to initiate a program to update their charts. This speaker and a Canadian researcher who worked with a similar approach were charged with developing a new chart. An algorithm was completed and the new chart was put into effect in Canada in October and in the U.S. in November, 2001.

  8. Bronchiectasis following pulmonary ammonia burn

    SciTech Connect

    Hoeffler, H.B.; Schweppe, H.I.; Greenberg, S.D.

    1982-12-01

    Long-term follow-up of the pulmonary lesions of severe exposure to ammonia in humans has seldom been documented, and development of bronchiectasis continues to be of concern. We studied a previously healthy 30-year-old woman whose lungs at time of necropsy, three years after massive exposure to ammonia fumes, had extensive cylindrical and saccular bronchiectasis. We concluded that massive exposure to ammonia can lead to bronchiectasis. It is not known, however, whether the bronchiectasis resulted from chemical injury by ammonia or from a superimposed bacterial bronchitis.

  9. Modeling and Test Data Analysis of a Tank Rapid Chill and Fill System for the Advanced Shuttle Upper Stage (ASUS) Concept

    NASA Technical Reports Server (NTRS)

    Flachbart, Robin; Hedayat, Ali; Holt, Kimberly A.; Cruit, Wendy (Technical Monitor)

    2001-01-01

    The Advanced Shuttle Upper Stage (ASUS) concept addresses safety concerns associated .with cryogenic stages by launching empty, and filling on ascent. The ASUS employs a rapid chill and fill concept. A spray bar is used to completely chill the tank before fill, allowing the vent valve to be closed during the fill process. The first tests of this concept, using a flight size (not flight weight) tank. were conducted at Marshall Space Flight Center (MSFC) during the summer of 2000. The objectives of the testing were to: 1) demonstrate that a flight size tank could be filled in roughly 5 minutes to accommodate the shuttle ascent window, and 2) demonstrate a no-vent fill of the tank. A total of 12 tests were conducted. Models of the test facility fill and vent systems, as well as the tank, were constructed. The objective of achieving tank fill in 5 minutes was met during the test series. However, liquid began to accumulate in the tank before it was chilled. Since the tank was not chilled until the end of each test, vent valve closure during fill was not possible. Even though the chill and fill process did not occur as expected, reasonable model correlation with the test data was achieved.

  10. Vapor Phase Catalytic Ammonia Reduction

    NASA Technical Reports Server (NTRS)

    Flynn, Michael T.; Harper, Lynn D. (Technical Monitor)

    1994-01-01

    This paper discusses the development of a Vapor Phase Catalytic Ammonia Reduction (VPCAR) teststand and the results of an experimental program designed to evaluate the potential of the technology as a water purification process. In the experimental program the technology is evaluated based upon product water purity, water recovery rate, and power consumption. The experimental work demonstrates that the technology produces high purity product water and attains high water recovery rates at a relatively high specific power consumption. The experimental program was conducted in 3 phases. In phase I an Igepon(TM) soap and water mixture was used to evaluate the performance of an innovative Wiped-Film Rotating-Disk evaporator and associated demister. In phase II a phenol-water solution was used to evaluate the performance of the high temperature catalytic oxidation reactor. In phase III a urine analog was used to evaluate the performance of the combined distillation/oxidation functions of the processor.

  11. Heat treatment alleviation of chilling-induced suppression of aroma volatile levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chilling exposure of tomatoes to 5 °C for longer than 6-8 days can cause surface pitting, irregular (blotchy) color development and other symptoms of chilling injury (CI). The objectives for this study were to investigate whether a 4-day exposure of tomato fruit to 5 °C chilling temperature at the m...

  12. 77 FR 12800 - Fresh and Chilled Atlantic Salmon From Norway: Revocation of Antidumping and Countervailing Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-02

    ... of Five-Year (``Sunset'') Review, 76 FR 89 (January 3, 2011); Fresh and Chilled Atlantic Salmon From... Duty Order, 76 FR 70409 (November 14, 2011), and Fresh and Chilled Atlantic Salmon From Norway: Final... Antidumping and Countervailing Duty Orders: Fresh and Chilled Atlantic Salmon from Norway, 71 FR...

  13. Temperature conditioning alters transcript abundance of genes related to chilling stress in 'Marsh' grapefruit flavedo

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grapefruit (Citrus x paradisi) develop symptoms of chilling injury (CI) if held at temperatures below about 10 degrees C. Conditioning grapefruit at a low, but non-chilling temperature prior to storage at a chilling temperature reduces the development of CI symptoms. Changes in transcript abundanc...

  14. Chilling and chipping influence plant growth and reproduction of star-of-Bethlehem (Ornithogalum umbellatum)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Greenhouse studies were conducted on two southern Illinois star-of-Bethlehem biotypes to determine the influence of chilling and bulb chipping on plant growth and reproduction. Chilling was not required for leaf emergence of dormant bulbs, but an increase to 10 weeks of chilling proportionally delay...

  15. Sensory descriptive Profiles of Air and Water Chilled Broiler Breast Fillets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Air chilled chicken products are gaining popularity in the USA. It has been claimed that air chilling (AC) results in improved tenderness and flavor of broiler meat compared with water chilling (WC). However, there was lack of published sensory study results to support the claims. The objective of...

  16. Combined effect of chilling and desiccation on survival of Escherichia coli suggests a transient loss of culturability.

    PubMed

    Mellefont, L A; Kocharunchitt, C; Ross, T

    2015-09-01

    Dry air carcass chilling regimes used in some Australian meat works, which not only rapidly reduce the temperature of the carcasses but also dry the meat surface initially, are reported to cause reductions in the number of Escherichia coli present on carcasses after processing. This study used a laboratory broth model system to systematically investigate the basis of such reductions by simulating chilling and desiccation profiles observed on carcasses separately and, finally, in combination. Observed growth was compared to the predictions generated by a strain-specific modification of a validated E. coli growth model (Mellefont et al., 2003; Performance evaluation of a model describing the effects of temperature, water activity, pH and lactic acid concentration on the growth of E. coli). Good agreement between observed and predicted growth was evident when chilling or desiccation profiles were simulated individually. However, when chilling and desiccation profiles were applied simultaneously the observed population kinetics deviated from those predicted by the model. An initial reduction in cell numbers, not predicted by the model, was observed followed by an anomalously rapid increase in population density before growth resumed at a rate expected for the conditions imposed. From our analysis of the kinetics of the population changes, we suggest that the initial decrease in cell numbers was unlikely due to cell death, because conditions were growth permissive. Considering all possible explanations from the observed population kinetics, we propose that a temporary loss of the ability to produce colonies on agar plates may occur. These results may explain reports of increases in E. coli numbers two to three days after commencement of chilling, compared to those observed after 16-24h, despite the imposition of growth-preventing temperatures. PMID:26004386

  17. Advances in Support of the CMAQ Bidirectional Science Option for the Estimation of Ammonia Flux from Agricultural cropland

    EPA Science Inventory

    Proposed Session: Emissions Inventories, Models and processes: Last year a new CMAQ bidirectional option for the estimation of ammonia flux (emission and deposition) was released. This option essentially replaces NEI crop ammonia emissions with emissions calculated dynamically...

  18. Ironmaking with ammonia at low temperature.

    PubMed

    Hosokai, Sou; Kasiwaya, Yoshiaki; Matsui, Kosuke; Okinaka, Noriyuki; Akiyama, Tomohiro

    2011-01-15

    This paper describes the reduction of hematite with ammonia for ironmaking, in which the effect of temperature on the products was examined. The results showed that the reduction process began at 430 °C during heating, and with an increase in temperature, the reduction mechanism changed apparently from a direct reduction of ammonia (Fe(2)O(3) + 2NH(3) → 2Fe + N(2) + 3H(2)O) to an indirect reduction via the thermal decomposition of ammonia (2NH(3) → N(2) + 3H(2), Fe(2)O(3) + 3H(2) → 2Fe + 3H(2)O) at temperatures over 530 °C. The final product obtained at 600 and 700 °C was pure metallic iron, in contrast with that formed at 450 °C, that is, a mixture of metallic iron and iron nitride. The results suggest the possibility of using ammonia as a reducing agent for carbonless ironmaking, which is operated at a much lower temperature than 900 °C in conventional coal-based ironmaking. PMID:21126038

  19. Differential expression proteins associated with bud dormancy release during chilling treatment of tree peony (Paeonia suffruticosa).

    PubMed

    Zhang, Y X; Yu, D; Tian, X L; Liu, C Y; Gai, S P; Zheng, G S

    2015-01-01

    Endo-dormant flower buds of tree peony must have sufficient chilling duration to reinitiate growth, which is a major obstacle to the forcing culture of tree peony in winter. We used a combination of two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionisation time of flight/time of flight mass spectrometry (MALDI-TOF/TOF MS) to identify the differentially expressed proteins of tree peony after three different chilling treatments: endo-dormancy, endo-dormancy release and eco-dormancy stages. More than 200 highly reproducible protein spots were detected, and 31 differentially expressed spots (P < 0.05) were selected for further analysis. Finally, 20 protein spots were confidently identified from databases, which were annotated and classified into seven functional categories: response to abiotic or biotic stimulus (four), metabolic processes (four), other binding (three), transcription or transcription regulation (two), biological processes (one), cell biogenesis (one) and unclassified (five). The results of qPCR of five genes were mainly consistent with that of the protein accumulation analysis as determined by 2-DE. This indicated that most of these genes were mainly regulated at transcriptional level. The activity of nitrate reductase and pyruvate dehydrogenase E1 was consistent with the 2-DE results. The proteomic profiles indicated activation of citrate cycle, amino acid metabolism, lipid metabolism, energy production, calcium signalling and cell growth processes by chilling fulfilment to facilitate dormancy release in tree peony. Analysis of functions of identified proteins will increase our knowledge of endo-dormancy release in tree peony. PMID:25091021

  20. Proteomic analysis of peach fruit mesocarp softening and chilling injury using difference gel electrophoresis (DIGE)

    PubMed Central

    2010-01-01

    Background Peach fruit undergoes a rapid softening process that involves a number of metabolic changes. Storing fruit at low temperatures has been widely used to extend its postharvest life. However, this leads to undesired changes, such as mealiness and browning, which affect the quality of the fruit. In this study, a 2-D DIGE approach was designed to screen for differentially accumulated proteins in peach fruit during normal softening as well as under conditions that led to fruit chilling injury. Results The analysis allowed us to identify 43 spots -representing about 18% of the total number analyzed- that show statistically significant changes. Thirty-nine of the proteins could be identified by mass spectrometry. Some of the proteins that changed during postharvest had been related to peach fruit ripening and cold stress in the past. However, we identified other proteins that had not been linked to these processes. A graphical display of the relationship between the differentially accumulated proteins was obtained using pairwise average-linkage cluster analysis and principal component analysis. Proteins such as endopolygalacturonase, catalase, NADP-dependent isocitrate dehydrogenase, pectin methylesterase and dehydrins were found to be very important for distinguishing between healthy and chill injured fruit. A categorization of the differentially accumulated proteins was performed using Gene Ontology annotation. The results showed that the 'response to stress', 'cellular homeostasis', 'metabolism of carbohydrates' and 'amino acid metabolism' biological processes were affected the most during the postharvest. Conclusions Using a comparative proteomic approach with 2-D DIGE allowed us to identify proteins that showed stage-specific changes in their accumulation pattern. Several proteins that are related to response to stress, cellular homeostasis, cellular component organization and carbohydrate metabolism were detected as being differentially accumulated

  1. Inhibition of photosynthesis by chilling in moderate light: a comparison of plants sensitive and insensitive to chilling.

    PubMed

    Hodgson, R A; Raison, J K

    1989-12-01

    Photosynthetic activity, in leaf slices and isolated thylakoids, was examined at 25° C after preincubation of the slices at either 25° C or 4° C at a moderate photon flux density (PFD) of 450 μmol·m(-2)·s(-1), or at 4° C in the dark. The plants used wereSpinacia oleracea L.,Cucumis sativus L. andNerium oleander L. which was acclimated to growth at 20° C or 45° C. The plants were grown at a PFD of 550 μmol·m(-2)·s(-1). Photosynthesis, measured as CO2-dependent O2 evolution, was not inhibited in leaf slices from any plant after preincubation at 25° C at a moderate PFD or at 4° C in the dark. However, exposure to 4° C at a moderate PFD induced an inhibition of CO2-dependent O2 evolution within 1 h inC. sativus, a chilling-sensitive plant, and in 45° C-grownN. oleander. The inhibition in these plants after 5 h reached 80% and 40%, respectively, and was independent of the CO2 concentration but was reduced at O2 concentrations of less than 3%. Methyl-viologen-dependent O2 exchange in leaf slices from these plants was not inhibited. There was no photoxidation of chlorophyll, in isolated thylakoids, or any inhibition of electron transport at photosystem (PS)II, PSI or through both photosystems which would account for the inhibition of photosynthesis. The conditions which inhibit photosynthesis in chilling-sensitive plants do not cause inhibition inS. oleracea, a chilling-insensitive plant, or in 20° C-grownN. oleander. The CO2-dependent photosynthesis, measured at 5° C, was reduced to about 3% of that recorded at 25° C in chilling-sensitive plants but only to about 30% in the chilling-insensitive plants. Methyl-viologen-dependent O2 exchange, measured at 5° C, was greater than 25% of the activity at 25° C in all the plants. The results indicate that the mechanism of the chilling-induced inhibition of photosynthesis does not involve damage to PSII. That inhibition of photosynthesis is observed only in the chilling-sensitive plants indicates it is

  2. The Sugar Model: Autocatalytic Activity of the Triose Ammonia Reaction

    NASA Astrophysics Data System (ADS)

    Weber, Arthur L.

    2007-04-01

    Reaction of triose sugars with ammonia under anaerobic conditions yielded autocatalytic products. The autocatalytic behavior of the products was examined by measuring the effect of the crude triose ammonia reaction product on the kinetics of a second identical triose ammonia reaction. The reaction product showed autocatalytic activity by increasing both the rate of disappearance of triose and the rate of formation of pyruvaldehyde, the product of triose dehydration. This synthetic process is considered a reasonable model of origin-of-life chemistry because it uses plausible prebiotic substrates, and resembles modern biosynthesis by employing the energized carbon groups of sugars to drive the synthesis of autocatalytic molecules.

  3. Primary arm spacing in chill block melt spun Ni-Mo alloys

    NASA Technical Reports Server (NTRS)

    Tewari, S. N.; Glasgow, T. K.

    1986-01-01

    Chill block melt spun ribbons of Ni-Mo binary alloys containing 8.0 to 41.8 wt % Mo have been prepared under carefully controlled processing conditions. The growth velocity has been determined as a function of distance from the quench surface from the observed ribbon thickness dependence on the melt puddle residence time. Primary arm spacings measured at the midribbon thickness locations show a dependence on growth velocity and alloy composition which is expected from dendritic growth models for binary alloys directionally solidified in a positive temperature gradient.

  4. Ammonia caramels: specifications and analysis.

    PubMed

    Patey, A L; Shearer, G; Knowles, M E; Denner, W H

    1985-01-01

    Twenty three UK commercially produced ammonia caramels and eight experimentally produced ammonia caramels have been analysed by a range of physical and chemical tests, which include solids content, nitrogen levels, colour intensity and pH. A statistical treatment of the results is reported. PMID:4018316

  5. Meaningful wind chill indicators derived from heat transfer principles.

    PubMed

    Brauner, N; Shacham, M

    1995-08-01

    The wind chill index (WCI) and the more widely used wind chill equivalent temperature represent an attempt to combine several weather-related variables (temperature, wind velocity and solar radiation) into a single index which can indicate human comfort. Since its introduction in 1945, the WCI has been criticized mainly on the ground that the underlying model does not comply with modern heat transfer theory. In spite of that, the WCI, "calibrated" to human comfort, has proven to be successful in predicting discomfort and tolerance of man to the cold. Nevertheless, neither the WCI nor the wind chill equivalent temperature can be actually measured and, therefore, without the additional 'calibration' they are meaningless. In this study we have shown that the WCI represents the instantaneous rate of heat loss from bare skin at the moment of exposure to the cold, and as such, it correlates reasonably well with measurable variables that represent a feeling of cold. Two new wind chill indicators have been introduced: exposed skin temperature and maximum exposure time. These indicators yield more information than the WCI provides, are measurable, have physical meaning and are based on established heat transfer principles. PMID:7558408

  6. Meaningful wind chill indicators derived from heat transfer principles

    NASA Astrophysics Data System (ADS)

    Brauner, Neima; Shacham, M.

    1995-03-01

    The wind chill index (WCI) and the more widely used wind chill equivalent temperature represent an attempt to combine several weather-related variables (temperature, wind velocity and solar radiation) into a single index which can indicate human comfort. Since its introduction in 1945, the WCI has been criticized mainly on the ground that the underlying model does not comply with modern heat transfer theory. In spite of that, the WCI, “calibrated” to human comfort, has proven to be successful in predicting discomfort and tolerance of man to the cold. Nevertheless, neither the WCI nor the wind chill equivalent temperature can be actually measured and, therefore, without the additional ‘calibration’ they are meaningless. In this study we have shown that the WCI represents the instantaneous rate of heat loss from bare skin at the moment of exposure to the cold, and as such, it correlates reasonably well with measurable variables that represent a feeling of cold. Two new wind chill indicators have been introduced: exposed skin temperature and maximum exposure time. These indicators yield more information than the WCI provides, are measurable, have physical meaning and are based on established heat transfer principles.

  7. 77 FR 10772 - Fresh and Chilled Atlantic Salmon From Norway

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-23

    ..., 2011 (76 FR 166) and determined on April 8, 2011 that it would conduct full reviews (76 FR 22422, April..., 2011 (76 FR 38698). The hearing was held in Washington, DC, on November 30, 2011, and all persons who... COMMISSION Fresh and Chilled Atlantic Salmon From Norway Determination On the basis of the record...

  8. Imagining Citizenship as Friendship in "The Big Chill"

    ERIC Educational Resources Information Center

    Kaplan, Michael

    2005-01-01

    This essay stages a theoretically driven critique of Lawrence Kasdan's film "The Big Chill" as a productive example of a constitutive contradiction animating the liberal political imaginary. In particular, it argues that liberalism relies irreducibly on an under-examined conception of friendship to supply its model of citizenship as a distinctive,…

  9. Chilling the Messenger: The Impact of Libel on Community Newspapers.

    ERIC Educational Resources Information Center

    Hansen, Elizabeth K.; Moore, Roy L.

    A study used a new attitude and behavioral scale for measuring the chilling effect--an undercurrent of fear with respect to publishing decisions--and to determine the impact, if any, of threatened or actual libel suits on community newspapers. The editors and/or publishers of all 167 newspapers in Kentucky with a circulation of less than 50,000…

  10. Microencapsulation of Bifidobacterium animalis subsp. lactis and Lactobacillus acidophilus in cocoa butter using spray chilling technology

    PubMed Central

    Pedroso, D.L.; Dogenski, M.; Thomazini, M.; Heinemann, R.J.B.; Favaro-Trindade, C.S.

    2013-01-01

    In the present study, the cells of Bifidobacterium animalis subsp. lactis (BI-01) and Lactobacillus acidophilus (LAC-04) were encapsulated in cocoa butter using spray-chilling technology. Survival assays were conducted to evaluate the resistance of the probiotics to the spray-chilling process, their resistance to the simulated gastric and intestinal fluids (SGF and SIF), and their stability during 90 days of storage. The viability of the cells was not affected by microencapsulation. The free and encapsulated cells of B. animalis subsp. lactis were resistant to both SGF and SIF. The micro-encapsulated cells of L. acidophilus were more resistant to SGF and SIF than the free cells; the viability of the encapsulated cells was enhanced by 67%, while the free cells reached the detection limit of the method (103 CFU/g). The encapsulated probiotics were unstable when they were stored at 20 °C. The population of encapsulated L. acidophilus decreased drastically when they were stored at 7 °C; only 20% of cells were viable after 90 days of storage. The percentage of viable cells of the encapsulated B. animalis subsp.lactis, however, was 72% after the same period of storage. Promising results were obtained when the microparticles were stored at −18 °C; the freeze granted 90 days of shelf life to the encapsulated cells. These results suggest that the spray-chilling process using cocoa butter as carrier protects L. acidophilus from gastrointestinal fluids. However, the viability of the cells during storage must be improved. PMID:24516445

  11. The production of ammonia by multiheme cytochromes C.

    PubMed

    Simon, Jörg; Kroneck, Peter M H

    2014-01-01

    The global biogeochemical nitrogen cycle is essential for life on Earth. Many of the underlying biotic reactions are catalyzed by a multitude of prokaryotic and eukaryotic life forms whereas others are exclusively carried out by microorganisms. The last century has seen the rise of a dramatic imbalance in the global nitrogen cycle due to human behavior that was mainly caused by the invention of the Haber-Bosch process. Its main product, ammonia, is a chemically reactive and biotically favorable form of bound nitrogen. The anthropogenic supply of reduced nitrogen to the biosphere in the form of ammonia, for example during environmental fertilization, livestock farming, and industrial processes, is mandatory in feeding an increasing world population. In this chapter, environmental ammonia pollution is linked to the activity of microbial metalloenzymes involved in respiratory energy metabolism and bioenergetics. Ammonia-producing multiheme cytochromes c are discussed as paradigm enzymes. PMID:25416396

  12. Ammonia synthesis and ER-MCFC-technology - a profitable combination?

    SciTech Connect

    Dijkema, G.P.J.; Vervoort, J.; Daniels, R.J.E.; Luteijn, C.P.

    1996-12-31

    Similar to stand-alone ER-MCFC power systems industrial ammonia production facilities include hydrogen-rich synthesis-gas production. Therefore, integration of ER-MCFC stacks in a conventional industrial ammonia plant was investigated. By preliminary process design calculations three promising process structures were evaluated: (1) ER-MCFC is fed by the ammonia plant`s steam-reformer; anode off-gas to firing (2) similar to structure 1; in this case the anode off-gas is redirected to the ammonia process (3) ER-MCFC is fed by ammonia-synthesis purge gas The results indicate that for options 1 and 3 a return-on-investment for the ER-MCFC of around 8% is achievable at a stack cost of $250/kW and a revenue of 7c/kWh. Option 2 is not profitable, because of the associated reduction in ammonia production. The degree of hydrogen-utilization in the ER-MCFC to be selected for maximum profit varies with the process structure and indicates that there is scope for ER-MCFC stacks which operate at low hydrogen-utilization.

  13. Transcript Profiling of Paoenia ostii during Artificial Chilling Induced Dormancy Release Identifies Activation of GA Pathway and Carbohydrate Metabolism

    PubMed Central

    Liu, Chunying; Zhang, Yang; Zheng, Guosheng

    2013-01-01

    Endo-dormant flower buds must pass through a period of chilling to reinitiate growth and subsequent flowering, which is a major obstacle to the forcing culture of tree peony in winter. Customized cDNA microarray (8×15 K element) was used to investigate gene expression profiling in tree peony ‘Feng Dan Bai’ buds during 24 d chilling treatment at 0–4°C. According to the morphological changes after the whole plants were transferred to green house, endo-dormancy was released after 18 d chilling treatment, and prolonged chilling treatment increased bud break rate. Pearson correlation hierarchical clustering of sample groups was highly consistent with the dormancy transitions revealed by morphological changes. Totally 3,174 significantly differentially-expressed genes (P<0.05) were observed through endo-dormancy release process, of which the number of up-regulated (1,611) and that of down-regulated (1,563) was almost the same. Functional annotation of differentially-expressed genes revealed that cellular process, metabolic process, response to stimulus, regulation of biological process and development process were well-represented. Hierarchical clustering indicated that activation of genes involved in carbohydrate metabolism (Glycolysis, Citrate cycle and Pentose phosphate pathway), energy metabolism and cell growth. Based on the results of GO analysis, totally 51 probes presented in the microarray were associated with GA response and GA signaling pathway, and 22 of them were differently expressed. The expression profiles also revealed that the genes of GA biosynthesis, signaling and response involved in endo-dormancy release. We hypothesized that activation of GA pathway played a central role in the regulation of dormancy release in tree peony. PMID:23405132

  14. QuikChill software for efficient chiller upgrade assessment

    SciTech Connect

    Rose, R.J.; Anderson, D.

    1998-07-01

    Chiller upgrades, required by recent CFC legislation, have not occurred in most large US facilities. Opportunities for compliance via efficient, correctly-sized chillers is significant, but there is little industry infrastructure encouraging downsizing and maximum efficiency, nor are changeouts approached as investments. Upgrade performance analysis is either too simplistic (missing integration and downsizing opportunities) or too difficult, detailed, and expensive. A niche exists for dedicated tools that can be used for both early screening and more detailed final design analysis, including downsizing, system integration, and staging. QuickChill, a chiller upgrade analysis software tool, as developed by EPA's ENERGY STAR Buildings Program to address these issues. It performs economic and energy analyses of potential centrifugal chiller upgrades using minimal information, and performs more accurate calculations as the quality and detail or inputs are increased. QuikChill assesses the consolidation of existing chillers, integration/staging of new chillers, and refrigerant conversion retrofits. QuikChill was designed for facility managers and consulting engineers facing CFC phaseouts. Rather than require time-consuming, detailed building shell and operational inputs, QuikChill estimates loads using DOE2-generated curves which plot the relationship between cooling load and outdoor temperature. Surprisingly, these curves reasonably predict annual cooling system operating requirements when used with local hourly temperatures and the peak load met by the existing system. Hourly temperature data is available for over 240 locations and users can easily supply peak information. QuikChill's combination of simplified inputs, investment-orientation, and unique approach to hourly cooling load estimation help fill an analytical void for the post-CFC chiller industry.

  15. Growth of Organic Microspherules in Sugar-Ammonia Reactions

    NASA Astrophysics Data System (ADS)

    Weber, Arthur L.

    2005-12-01

    Reaction of small sugars of less than four carbons with ammonia in water yielded organic microspherules generally less than ten microns in size. The time course of microspherule growth was examined for the D-erythrose-ammonia reaction that yielded microspherules attached to the glass walls of containers. Measurements were made of the elemental composition and infrared spectrum of the microspherule material. These viscose semi-solid microspherules are viewed as possible containers for prebiotic catalytic processes relevant to the origin of life.

  16. Submersible microbial desalination cell for simultaneous ammonia recovery and electricity production from anaerobic reactors containing high levels of ammonia.

    PubMed

    Zhang, Yifeng; Angelidaki, Irini

    2015-02-01

    High ammonia concentration in anaerobic reactors can seriously inhibit the anaerobic digestion process. In this study, a submersible microbial desalination cell (SMDC) was developed as an innovative method to lower the ammonia level in a continuous stirred tank reactor (CSTR) by in situ ammonia recovery and electricity production. In batch experiment, the ammonia concentration in the CSTR decreased from 6 to 0.7 g-N/L during 30 days, resulting in an average recovery rate of 80 g-N/m(2)/d. Meanwhile, a maximum power density of 0.71±0.5 W/m(2) was generated at 2.85 A/m(2). Both current driven NH4(+) migration and free NH3 diffusion were identified as the mechanisms responsible for the ammonia transportation. With an increase in initial ammonia concentration and a decrease in external resistance, the SMDC performance was enhanced. In addition, the coexistence of other cations in CSTR or cathode had no negative effect on the ammonia transportation. PMID:25496943

  17. Characteristics of Three Thioredoxin Genes and Their Role in Chilling Tolerance of Harvested Banana Fruit.

    PubMed

    Wu, Fuwang; Li, Qing; Yan, Huiling; Zhang, Dandan; Jiang, Guoxiang; Jiang, Yueming; Duan, Xuewu

    2016-01-01

    Thioredoxins (Trxs) are small proteins with a conserved redox active site WCGPC and are involved in a wide range of cellular redox processes. However, little information on the role of Trx in regulating low-temperature stress of harvested fruit is available. In this study, three full-length Trx cDNAs, designated MaTrx6, MaTrx9 and MaTrx12, were cloned from banana (Musa acuminata) fruit. Phylogenetic analysis and protein sequence alignments showed that MaTrx6 was grouped to h2 type with a typical active site of WCGPC, whereas MaTrx9 and MaTrx12 were assigned to atypical cys his-rich Trxs (ACHT) and h3 type with atypical active sites of GCAGC and WCSPC, respectively. Subcellular localization indicated that MaTrx6 and MaTrx12 were located in the plasma membrane and cytoplasm, respectively, whereas MaTrx9 showed a dual cytoplasmic and chloroplast localization. Application of ethylene induced chilling tolerance of harvested banana fruit, whereas 1-MCP, an inhibitor of ethylene perception, aggravated the development of chilling injury. RT-qPCR analysis showed that expression of MaTrx12 was up-regulated and down-regulated in ethylene- and 1-MCP-treated banana fruit at low temperature, respectively. Furthermore, heterologous expression of MaTrx12 in cytoplasmic Trx-deficient Saccharomyces cerevisiae strain increased the viability of the strain under H₂O₂. These results suggest that MaTrx12 plays an important role in the chilling tolerance of harvested banana fruit, possibly by regulating redox homeostasis. PMID:27618038

  18. Ammonia Ice Clouds on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The top cloud layer on Jupiter is thought to consist of ammonia ice, but most of that ammonia 'hides' from spectrometers. It does not absorb light in the same way ammonia does. To many scientists, this implies that ammonia churned up from lower layers of the atmosphere 'ages' in some way after it condenses, possibly by being covered with a photochemically generated hydrocarbon mixture. The New Horizons Linear Etalon Imaging Spectral Array (LEISA), the half of the Ralph instrument that is able to 'see' in infrared wavelengths that are absorbed by ammonia ice, spotted these clouds and watched them evolve over five Jupiter days (about 40 Earth hours). In these images, spectroscopically identified fresh ammonia clouds are shown in bright blue. The largest cloud appeared as a localized source on day 1, intensified and broadened on day 2, became more diffuse on days 3 and 4, and disappeared on day 5. The diffusion seemed to follow the movement of a dark spot along the boundary of the oval region. Because the source of this ammonia lies deeper than the cloud, images like these can tell scientists much about the dynamics and heat conduction in Jupiter's lower atmosphere.

  19. AQUEOUS AMMONIA EQUILIBRIUM - TABULATION OF PERCENT UN-IONIZED AMMONIA

    EPA Science Inventory

    The percent of un-ionized ammonia as a function of pH and temperature in aqueous ammonia solutions of zero salinity is presented in tabular form over the following ranges: temperature 0.0 to 40.0 C in increments of 0.2 degree, and pH 5.00 to 12.00 in increments of 0.01 pH unit.

  20. Development of a convenience and safety chilled sous vide fish dish: Diversification of aquacultural products.

    PubMed

    Espinosa, M C; López, G; Díaz, P; Linares, M B; Garrido, M D

    2016-04-01

    The dynamic expansion of the ready-to-eat seabream sector in its adaptation to new lifestyles has led to the search for new presentation formats in seabream (Sparus aurata). Green sauce (olive oil, wine vinegar, garlic, fresh parsley, black pepper, basil and salt) and 60 ℃ of cooking temperature were chosen by the panellists for the sous vide cooking process. Seabream fillet and sauce were packaged in polypropylene trays, cooked, chilled and stored at 2 ℃. Microbiological (total viable counts,Enterobacteriaceae,lactic acid bacteria, anaerobic psychrotrophic, moulds and yeasts, Salmonella and Listeria monocytogenes), chemical (pH and TBARs) and sensory parameters were determined at 0, 7, 17, 34, 48 and 62 days. In the conditions used, the microbiological counts remained stable, and Salmonella and Listeria monocytogenes were absent. The acidic sauce had a positive effect on the pH of the product, and low TBARs were obtained throughout storage. The processing conditions used in the present study allowed a chilled ready-to-eat seabream product of consistently high quality up to 62 days of storage to be obtained, representing an expansion of the products offered by the aquacultural industry. PMID:25941212

  1. Biogenic amines in pressurized vacuum-packaged cooked sliced ham under different chilled storage conditions.

    PubMed

    Ruiz-Capillas, C; Carballo, J; Jiménez Colmenero, F

    2007-03-01

    This work was undertaken to study how storage conditions (at constant temperatures of 2±1 and 12±1°C and temperature fluctuations at 7±5°C) affect microbial development and the production of biogenic amines in vacuum-packaged cooked sliced ham subjected to high pressure (400MPa/10min/30°C). Initially, the product exhibited low levels of contamination. Microbiological changes during storage depend on the processing (non-pressure and pressure treatment) and the chilled storage conditions. Generally, microbial growth in pressurized samples was similar to that in the non-pressurized samples, although the total viable count and lactic flora were lower and growth was delayed. Processing and storage conditions affected the formation of each amine differently. The most important changes were in tyramine, which formed more quickly in non-pressurized products stored at 12°C and with temperature fluctuations. The formation of biogenic amines in these products can be prevented not only by ensuring good manufacturing practices and applying high pressure but also by ensuring the right chilled storage conditions. PMID:22063795

  2. ENGINEERING DESIGN CONFIGURATIONS FOR BIOLOGICAL AMMONIA REMOVAL

    EPA Science Inventory

    Many regions in the United States have excessive levels of nutrients including ammonia in their source waters. For example, farming and agricultural sources of ammonia in the Midwest contribute to relatively high levels of ammonia in many ground waters. Although ammonia in water ...

  3. Interorgan ammonia metabolism in health and disease: a surgeon's view.

    PubMed

    Souba, W W

    1987-01-01

    Ammonia is a toxic molecule that is the principal by-product of amino acid metabolism. Although the transport of ammonia in a nontoxic form protects the brain against high circulating levels, the interorgan transport of this molecule and the orchestration between tissues that has evolved is related primarily to the fact that the nitrogen molecule is an essential molecule for the maintenance of the body's nutrition economy and overall metabolic homeostasis. Efficient handling and disposal of ammonia requires a cooperative effort between tissues in order to maintain nitrogen homeostasis. The liver is the central organ of ammonia metabolism, but other organs also play a key role in the interorgan exchange of this molecule. Alterations in ammonia metabolism occur during critical illness. These changes are adaptive and are designed to maintain metabolic homeostasis. Interorgan cooperation in ammonia metabolism is necessary to insure the proper integration of the metabolic processes which contribute to and are essential for survival during critical illness. An understanding of these processes improves our knowledge of metabolic regulation and will lead to a rational approach to the nutritional and metabolic support provided to critically ill patients. PMID:3323556

  4. Use of smart photochromic indicator for dynamic monitoring of the shelf life of chilled chicken based products.

    PubMed

    Brizio, Ana Paula Dutra Resem; Prentice, Carlos

    2014-03-01

    This study evaluated the applicability of a photochromic time temperature indicator (TTI) to monitor the time-temperature history and shelf life of chilled boneless chicken breast. The results showed that the smart indicator showed good reproducibility during the discoloring process in all the conditions investigated. The response was not only visibly interpretable but also well adaptable to measurement using appropriate equipment. For an activation configuration of 4 s of ultraviolet light (UV) per label, the TTI's rate of discoloration was similar to the quality loss of the meat samples analyzed. Thus, the photochromic label (4 s UV/label) attached to the samples set out to be a dynamic shelf-life label, assuring consumers the final point of quality of chilled boneless chicken breast in an easy and precise form, providing a reliable tool to monitor the supply chain of this product. PMID:24334043

  5. Refining the ammonia hypothesis: a physiology-driven approach to the treatment of hepatic encephalopathy.

    PubMed

    Tapper, Elliot B; Jiang, Z Gordon; Patwardhan, Vilas R

    2015-05-01

    Hepatic encephalopathy (HE) is one of the most important complications of cirrhosis and portal hypertension. Although the etiology is incompletely understood, it has been linked to ammonia directly and indirectly. Our goal is to review for the clinician the mechanisms behind hyperammonemia and the pathogenesis of HE to explain the rationale for its therapy. We reviewed articles collected through a search of MEDLINE/PubMed, Cochrane Database of Systematic Reviews, and Google Scholar between October 1, 1948, and December 8, 2014, and by a manual search of citations within retrieved articles. Search terms included hepatic encephalopathy, ammonia hypothesis, brain and ammonia, liver failure and ammonia, acute-on-chronic liver failure and ammonia, cirrhosis and ammonia, portosytemic shunt, ammonia and lactulose, rifaximin, zinc, and nutrition. Ammonia homeostatsis is a multiorgan process involving the liver, brain, kidneys, and muscle as well as the gastrointestinal tract. Indeed, hyperammonemia may be the first clue to poor functional reserves, malnutrition, and impending multiorgan dysfunction. Furthermore, the neuropathology of ammonia is critically linked to states of systemic inflammation and endotoxemia. Given the complex interplay among ammonia, inflammation, and other factors, ammonia levels have questionable utility in the staging of HE. The use of nonabsorbable disaccharides, antibiotics, and probiotics reduces gut ammoniagenesis and, in the case of antibiotics and probiotics, systemic inflammation. Nutritional support preserves urea cycle function and prevents wasting of skeletal muscle, a significant site of ammonia metabolism. Correction of hypokalemia, hypovolemia, and acidosis further assists in the reduction of ammonia production in the kidney. Finally, early and aggressive treatment of infection, avoidance of sedatives, and modification of portosystemic shunts are also helpful in reducing the neurocognitive effects of hyperammonemia. Refining the

  6. Prevalence and serogroup diversity of Salmonella for broiler neck skin, whole carcass rinse, and whole carcass enrichment sampling methodologies following air or immersion chilling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to evaluate neck skin (NS), whole carcass rinse (WCR), and whole carcass enrichment (WCE) sampling procedures for Salmonella isolation and serogroup from the same broiler carcass following either air or immersion chilling. Commercially processed and eviscerated broiler ...

  7. Tradeoffs between chilling and forcing in satisfying dormancy requirements for Pacific Northwest tree species

    PubMed Central

    Harrington, Constance A.; Gould, Peter J.

    2015-01-01

    Many temperate and boreal tree species have a chilling requirement, that is, they need to experience cold temperatures during fall and winter to burst bud normally in the spring. Results from trials with 11 Pacific Northwest tree species are consistent with the concept that plants can accumulate both chilling and forcing units simultaneously during the dormant season and they exhibit a tradeoff between amount of forcing and chilling. That is, the parallel model of chilling and forcing was effective in predicting budburst and well chilled plants require less forcing for bud burst than plants which have received less chilling. Genotypes differed in the shape of the possibility line which describes the quantitative tradeoff between chilling and forcing units. Plants which have an obligate chilling requirement (Douglas-fir, western hemlock, western larch, pines, and true firs) and received no or very low levels of chilling did not burst bud normally even with long photoperiods. Pacific madrone and western redcedar benefited from chilling in terms of requiring less forcing to promote bud burst but many plants burst bud normally without chilling. Equations predicting budburst were developed for each species in our trials for a portion of western North America under current climatic conditions and for 2080. Mean winter temperature was predicted to increase 3.2–5.5°C and this change resulted in earlier predicted budburst for Douglas-fir throughout much of our study area (up to 74 days earlier) but later budburst in some southern portions of its current range (up to 48 days later) as insufficient chilling is predicted to occur. Other species all had earlier predicted dates of budburst by 2080 than currently. Recent warming trends have resulted in earlier budburst for some woody plant species; however, the substantial winter warming predicted by some climate models will reduce future chilling in some locations such that budburst will not consistently occur earlier. PMID

  8. Getter materials for cracking ammonia

    DOEpatents

    Boffito, Claudio; Baker, John D.

    1999-11-02

    A method is provided for cracking ammonia to produce hydrogen. The method includes the steps of passing ammonia over an ammonia-cracking catalyst which is an alloy including (1) alloys having the general formula Zr.sub.1-x Ti.sub.x M.sub.1 M.sub.2, wherein M.sub.1 and M.sub.2 are selected independently from the group consisting of Cr, Mn, Fe, Co, and Ni, and x is between about 0.0 and about 1.0 inclusive; and between about 20% and about 50% Al by weight. In another aspect, the method of the invention is used to provide methods for operating hydrogen-fueled internal combustion engines and hydrogen fuel cells. In still another aspect, the present invention provides a hydrogen-fueled internal combustion engine and a hydrogen fuel cell including the above-described ammonia-cracking catalyst.

  9. Compatibility testing with anhydrous ammonia

    NASA Technical Reports Server (NTRS)

    Benner, Steve M.; Schweickart, Russell B.

    1992-01-01

    Anhydrous ammonia has been proposed as the working fluid for a number of two-phase thermal control systems to be used in future space applications, including the Space Station Freedom and the Earth Observing Station (EOS). The compatibility of ammonia with the components in these systems is a major concern due to the corrosive nature of the fluid. Compatibility of ammonia with stainless steel and some aluminum alloys is well documented; however, data on other materials potentially suitable for aerospace use is less common. This paper documents the compatibility testing of nine materials with both gaseous and liquid ammonia. The test procedures are presented along with the resulting measurement data. Tensile strength was the only mechanical property tested that indicated a significant material incompatibility.

  10. Satellite Observations of Tropospheric Ammonia

    NASA Astrophysics Data System (ADS)

    Shephard, M. W.; Luo, M.; Rinsland, C. P.; Cady-Pereira, K. E.; Beer, R.; Pinder, R. W.; Henze, D.; Payne, V. H.; Clough, S.; Rodgers, C. D.; Osterman, G. B.; Bowman, K. W.; Worden, H. M.

    2008-12-01

    Global high-spectral resolution (0.06 cm-1) nadir measurements from TES-Aura enable the simultaneous retrieval of a number of tropospheric pollutants and trace gases in addition to the TES standard operationally retrieved products (e.g. carbon monoxide, ozone). Ammonia (NH3) is one of the additional species that can be retrieved in conjunction with the TES standard products, and is important for local, regional, and global tropospheric chemistry studies. Ammonia emissions contribute significantly to several well-known environmental problems, yet the magnitude and seasonal/spatial variability of the emissions are poorly constrained. In the atmosphere, an important fraction of fine particulate matter is composed of ammonium nitrate and ammonium sulfate. These particles are statistically associated with health impacts. When deposited to ecosystems in excess, nitrogen, including ammonia can cause nutrient imbalances, change in ecosystem species composition, eutrophication, algal blooms and hypoxia. Ammonia is also challenging to measure in-situ. Observations of surface concentrations are rare and are particularly sparse in North America. Satellite observations of ammonia are therefore highly desirable. We recently demonstrated that tropospheric ammonia is detectable in the TES spectra and presented some corresponding preliminary retrievals over a very limited range of conditions (Beer et al., 2008). Presented here are results that expand upon these initial TES ammonia retrievals in order to evaluate/validate the retrieval results utilizing in-situ surface observations (e.g. LADCO, CASTNet, EPA /NC State) and chemical models (e.g. GEOS-Chem and CMAQ). We also present retrievals over regions of interest that have the potential to help further understand air quality and the active nitrogen cycle. Beer, R., M. W. Shephard, S. S. Kulawik, S. A. Clough, A. Eldering, K. W. Bowman, S. P. Sander, B. M. Fisher, V. H. Payne, M. Luo, G. B. Osterman, and J. R. Worden, First

  11. Rapid-Chill Cryogenic Coaxial Direct-Acting Solenoid Valve

    NASA Technical Reports Server (NTRS)

    Richard, James; Castor, Jim; Sheller, Richard

    2006-01-01

    A commercially available cryogenic direct- acting solenoid valve has been modified to incorporate a rapid-chill feature. The net effect of the modifications is to divert some of the cryogenic liquid to the task of cooling the remainder of the cryogenic liquid that flows to the outlet. Among the modifications are the addition of several holes and a gallery into a valve-seat retainer and the addition of a narrow vent passage from the gallery to the atmosphere.

  12. Inhibition of flowering 'Arbequina' olives from chilling at lower temperatures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of four nighttime chilling temperatures on the induction of flowering in ‘Arbequina’ olives was investigated. Daytime temperature was kept at 17.5 ± 0.8°C (8 hrs) while nighttime temperatures (8 hrs ) were maintained at 7.8 ± 0.5, 4.4 ± 0.5, 2.2 ± 0.5, or -1.2 ± 0.6°C; transition from da...

  13. Chill-inducing music enhances altruism in humans.

    PubMed

    Fukui, Hajime; Toyoshima, Kumiko

    2014-01-01

    Music is a universal feature of human cultures, and it has both fascinated and troubled many researchers. In this paper we show through the dictator game (DG) that an individual's listening to preferred "chill-inducing" music may promote altruistic behavior that extends beyond the bounds of kin selection or reciprocal altruism. Participants were 22 undergraduate and postgraduate students who were divided into two groups, the in-group and the out-group, and they acted as dictators. The dictators listened to their own preferred "chill-inducing" music, to music they disliked, or to silence, and then played the DG. In this hypothetical experiment, the dictators were given real money (which they did not keep) and were asked to distribute it to the recipients, who were presented as stylized images of men and women displayed on a computer screen. The dictators played the DG both before and after listening to the music. Both male and female dictators gave more money after listening to their preferred music and less after listening to the music they disliked, whereas silence had no effect on the allocated amounts. The group to which the recipient belonged did not influence these trends. The results suggest that listening to preferred "chill-inducing" music promotes altruistic behavior. PMID:25389411

  14. Chill-inducing music enhances altruism in humans

    PubMed Central

    Fukui, Hajime; Toyoshima, Kumiko

    2014-01-01

    Music is a universal feature of human cultures, and it has both fascinated and troubled many researchers. In this paper we show through the dictator game (DG) that an individual’s listening to preferred “chill-inducing” music may promote altruistic behavior that extends beyond the bounds of kin selection or reciprocal altruism. Participants were 22 undergraduate and postgraduate students who were divided into two groups, the in-group and the out-group, and they acted as dictators. The dictators listened to their own preferred “chill-inducing” music, to music they disliked, or to silence, and then played the DG. In this hypothetical experiment, the dictators were given real money (which they did not keep) and were asked to distribute it to the recipients, who were presented as stylized images of men and women displayed on a computer screen. The dictators played the DG both before and after listening to the music. Both male and female dictators gave more money after listening to their preferred music and less after listening to the music they disliked, whereas silence had no effect on the allocated amounts. The group to which the recipient belonged did not influence these trends. The results suggest that listening to preferred “chill-inducing” music promotes altruistic behavior. PMID:25389411

  15. "Chilled" pork--Part II. Consumer perception of sensory quality.

    PubMed

    Ngapo, T M; Riendeau, L; Laberge, C; Fortin, J

    2012-12-01

    The objective of this study was to compare consumer perception of the sensory quality of grilled Canadian pork destined for Japanese and domestic markets, with particular reference to export selection criteria imposed by Japanese importers and transportation conditions. Consumers from Quebec, Canada tasted local and export quality pork subjected to "chilled" (aged 43 days at -1.7 °C) or conventional ageing (5 days at 3.1 °C). Consumers' scores (out of 10) were higher (P<0.05) in the "chilled" than conventionally aged pork for tenderness (6.8 vs 5.7), juiciness (6.6 vs 6.0), taste liking (6.4 vs 5.9) and overall acceptability (6.7 vs 6.1). When informed that the conventionally aged, domestic quality pork was destined for the domestic market, consumer scores increased significantly (P<0.05). No effect of information was observed on the perception of the 'chilled' export quality meat, perhaps a consequence of the high sensory quality observed prior to labelling. PMID:22647653

  16. Macrosegregation in horizontal direct chill casting of ternary Al alloys: Investigation of solid motion

    NASA Astrophysics Data System (ADS)

    Vušanović, I.; Krane, M. J. M.

    2012-01-01

    Macrosegregation in direct chill casting processes is controlled by fluid flow due to the thermosolutal natural and forced convection, shrinkage, and transport of unattached solid grains. Because grain refinement is usually used in aluminum direct chill casting, some effort must be made to model free-floating solid grains, and their attachment to a rigid mushy zone. Criteria for attachment vary, but many are based on using a critical solid packing fraction, which is treated as uniform and constant throughout the domain. In the case of horizontal casting (HDC), gravity acts perpendicularly to the casting direction, and the assumption of a uniform packing fraction cannot be applied because the solid particles attach to some surfaces by settling and others by being swept into the rigid solid from below. In this simulation of HDC casting of an Al-Cu-Mg alloy, the rigid and unattached solid is tracked separately, and a rule set is developed to determine the attachment of free-floating solid. Comparison between cases with and without unattached solid movement shows qualitatively different results, particularly in bottom part of slab. Non-uniform packing fractions cause very different segregation patterns in the lower half of the ingot compared to the cases with no solid movement, less segregation near centerline compared to uniform packing fraction cases, and positive segregation near the place where inlet jet impinges on the mushy zone.

  17. Mechanism of ammonia excretion in the freshwater leech Nephelopsis obscura: characterization of a primitive Rh protein and effects of high environmental ammonia.

    PubMed

    Quijada-Rodriguez, Alex R; Treberg, Jason R; Weihrauch, Dirk

    2015-09-15

    Remarkably little is known about nitrogenous excretion in freshwater invertebrates. In the current study, the nitrogen excretion mechanism in the carnivorous ribbon leech, Nephelopsis obscura, was investigated. Excretion experiments showed that the ribbon leech is ammonotelic, excreting 166.0 ± 8.6 nmol·grams fresh weight (gFW)(-1)·h(-1) ammonia and 14.7 ± 1.9 nmol·gFW(-1)·h(-1) urea. Exposure to high and low pH hampered and enhanced, respectively, ammonia excretion rates, indicating an acid-linked ammonia trapping mechanism across the skin epithelia. Accordingly, compared with body tissues, the skin exhibited elevated mRNA expression levels of a newly identified Rhesus protein and at least in tendency the Na(+)/K(+)-ATPase. Pharmacological experiments and enzyme assays suggested an ammonia excretion mechanism that involves the V-ATPase, Na(+)/K(+)-ATPase, and carbonic anhydrase, but not necessarily a functional microtubule system. Most importantly, functional expression studies of the identified Rh protein cloned from leech skin tissue revealed an ammonia transport capability of this protein when expressed in yeast. The leech Rh-ammonia transporter (NoRhp) is a member of the primitive Rh protein family, which is a sister group to the common ancestor of vertebrate ammonia-transporting Rh proteins. Exposure to high environmental ammonia (HEA) caused a new adjustment of body ammonia, accompanied with a decrease in NoRhp and Na(+)/K(+)-ATPase mRNA levels, but unaltered ammonia excretion rates. To our knowledge, this is only the second comprehensive study regarding the ammonia excretion mechanisms in a freshwater invertebrate, but our results show that basic processes of ammonia excretion appear to also be comparable to those found in freshwater fish, suggesting an early evolution of ionoregulatory mechanisms in freshwater organisms. PMID:26180186

  18. Ammonia concentration modeling based on retained gas sampler data

    SciTech Connect

    Terrones, G.; Palmer, B.J.; Cuta, J.M.

    1997-09-01

    The vertical ammonia concentration distributions determined by the retained gas sampler (RGS) apparatus were modeled for double-shell tanks (DSTs) AW-101, AN-103, AN-104, and AN-105 and single-shell tanks (SSTs) A-101, S-106, and U-103. One the vertical transport of ammonia in the tanks were used for the modeling. Transport in the non-convective settled solids and floating solids layers is assumed to occur primarily via some type of diffusion process, while transport in the convective liquid layers is incorporated into the model via mass transfer coefficients based on empirical correlations. Mass transfer between the top of the waste and the tank headspace and the effects of ventilation of the headspace are also included in the models. The resulting models contain a large number of parameters, but many of them can be determined from known properties of the waste configuration or can be estimated within reasonable bounds from data on the waste samples themselves. The models are used to extract effective diffusion coefficients for transport in the nonconvective layers based on the measured values of ammonia from the RGS apparatus. The modeling indicates that the higher concentrations of ammonia seen in bubbles trapped inside the waste relative to the ammonia concentrations in the tank headspace can be explained by a combination of slow transport of ammonia via diffusion in the nonconvective layers and ventilation of the tank headspace by either passive or active means. Slow transport by diffusion causes a higher concentration of ammonia to build up deep within the waste until the concentration gradients between the interior and top of the waste are sufficient to allow ammonia to escape at the same rate at which it is being generated in the waste.

  19. Removal and recovery of ammonia from liquid manure using gas-permeable membranes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated the use of gas-permeable membranes as components of a new process to capture and recover ammonia from liquid manures and other concentrated effluents. The process includes the passage of gaseous ammonia through a microporous hydrophobic membrane and capture and concentration with cir...

  20. Removal and recovery of ammonia from liquid swine manure and poultry litter using gas permeable membranes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated the use of gas-permeable membranes as components of new processes to capture and recover ammonia from liquid manures and other concentrated effluents as well as from the air in poultry houses. The basic process includes the passage of gaseous ammonia through a microporous hydrophobic...

  1. Recovery of ammonia from anaerobically digested manure using gas-permeable membranes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The gas-permeable membrane process can recover ammonia from wastewater with high nitrogen load, reducing pollution whilst converting ammonia into an ammonium salt fertilizer. The process involves manure pH control to increase ammonium (NH4) recovery rate that is normally carried out using an alkali....

  2. Optimality in the zonation of ammonia detoxification in rodent liver.

    PubMed

    Bartl, Martin; Pfaff, Michael; Ghallab, Ahmed; Driesch, Dominik; Henkel, Sebastian G; Hengstler, Jan G; Schuster, Stefan; Kaleta, Christoph; Gebhardt, Rolf; Zellmer, Sebastian; Li, Pu

    2015-11-01

    The rodent liver eliminates toxic ammonia. In mammals, three enzymes (or enzyme systems) are involved in this process: glutaminase, glutamine synthetase and the urea cycle enzymes, represented by carbamoyl phosphate synthetase. The distribution of these enzymes for optimal ammonia detoxification was determined by numerical optimization. This in silico approach predicted that the enzymes have to be zonated in order to achieve maximal removal of toxic ammonia and minimal changes in glutamine concentration. Using 13 compartments, representing hepatocytes, the following predictions were generated: glutamine synthetase is active only within a narrow pericentral zone. Glutaminase and carbamoyl phosphate synthetase are located in the periportal zone in a non-homogeneous distribution. This correlates well with the paradoxical observation that in a first step glutamine-bound ammonia is released (by glutaminase) although one of the functions of the liver is detoxification by ammonia fixation. The in silico approach correctly predicted the in vivo enzyme distributions also for non-physiological conditions (e.g. starvation) and during regeneration after tetrachloromethane (CCl4) intoxication. Metabolite concentrations of glutamine, ammonia and urea in each compartment, representing individual hepatocytes, were predicted. Finally, a sensitivity analysis showed a striking robustness of the results. These bioinformatics predictions were validated experimentally by immunohistochemistry and are supported by the literature. In summary, optimization approaches like the one applied can provide valuable explanations and high-quality predictions for in vivo enzyme and metabolite distributions in tissues and can reveal unknown metabolic functions. PMID:26438405

  3. Experimental study of graphitic nanoribbon films for ammonia sensing

    NASA Astrophysics Data System (ADS)

    Johnson, Jason L.; Behnam, Ashkan; An, Yanbin; Pearton, S. J.; Ural, Ant

    2011-06-01

    We fabricate and study the ammonia sensing properties of graphitic nanoribbon films consisting of multi-layer graphene nanoribbons. These films show very good sensitivity to parts-per-million (ppm) level concentrations of ammonia, which is further enhanced by platinum functionalization, resulting in a relative resistance response of ˜70% when exposed to 50 ppm ammonia. In addition, the sensing response exhibits excellent repeatability and full recovery in air. We also study in detail the dependence of the sensing response on ammonia concentration and temperature. We find that the relative resistance response of the graphitic nanoribbon films shows a power-law dependence on the ammonia concentration, which can be explained based on the Freundlich isotherm. The activation energy obtained from an Arrhenius plot of the temperature-dependent measurements is ˜50 meV, which is consistent with the theoretical calculations of the adsorption energies of ammonia on large graphene sheets and nanoribbons. Their simple and low-cost fabrication process and good sensing response open up the possibility of using graphitic nanoribbon films for large-scale sensing applications.

  4. A Pervaporation Study of Ammonia Solutions Using Molecular Sieve Silica Membranes

    PubMed Central

    Yang, Xing; Fraser, Thomas; Myat, Darli; Smart, Simon; Zhang, Jianhua; Diniz da Costa, João C.; Liubinas, Audra; Duke, Mikel

    2014-01-01

    An innovative concept is proposed to recover ammonia from industrial wastewater using a molecular sieve silica membrane in pervaporation (PV), benchmarked against vacuum membrane distillation (VMD). Cobalt and iron doped molecular sieve silica-based ceramic membranes were evaluated based on the ammonia concentration factor downstream and long-term performance. A modified low-temperature membrane evaluation system was utilized, featuring the ability to capture and measure ammonia in the permeate. It was found that the silica membrane with confirmed molecular sieving features had higher water selectivity over ammonia. This was due to a size selectivity mechanism that favoured water, but blocked ammonia. However, a cobalt doped silica membrane previously treated with high temperature water solutions demonstrated extraordinary preference towards ammonia by achieving up to a 50,000 mg/L ammonia concentration (a reusable concentration level) measured in the permeate when fed with 800 mg/L of ammonia solution. This exceeded the concentration factor expected by the benchmark VMD process by four-fold, suspected to be due to the competitive adsorption of ammonia over water into the silica structure with pores now large enough to accommodate ammonia. However, this membrane showed a gradual decline in selectivity, suspected to be due to the degradation of the silica material/pore structure after several hours of operation. PMID:24957120

  5. Global Seabird Ammonia Emissions

    NASA Astrophysics Data System (ADS)

    Riddick, S. N.; Blackall, T. D.; Dragosits, U.; Daunt, F. H.; Braban, C. F.; Tang, Y. S.; Trathan, P.; Wanless, S.; Sutton, M. A.

    2010-12-01

    Seabird colonies represent a major source of atmospheric ammonia (NH3) in remote coastal and marine systems in temperate, tropical and polar regions. Previous studies have shown that NH3 emissions from Scottish seabird colonies were substantial - of similar magnitude to the most intensive agricultural point source emissions. The UK data were used to model global seabird NH3 emissions and suggested that penguins are a major source of emissions on and around the Antarctic continent. The largest seabird colonies are in the order of millions of seabirds. Due to the isolation of these colonies from anthropogenic nitrogen sources, they may play a major role in the nitrogen cycle within these ecosystems. A global seabird database was constructed and used in conjunction with a species-specific seabird bioenergetics model to map the locations of NH3 emissions from seabird colonies. The accuracy of the modelled emissions was validated with field data of NH3 emissions measured at key seabird colonies in different climatic regions of the world: temperate (Isle of May, Scotland), tropical (Ascension Island) and polar (Signy Island, South Georgia). The field data indicated good agreement between modelled and measured NH3 emissions. The measured NH3 emissions also showed the variability of emission with climate. Climate dependence of seabird NH3 emissions may have further implications under a changing global climate. Seabird colonies represent NH3 emission ‘hotspots’, often far from anthropogenic sources, and are likely to be the major source of nitrogen input to these remote coastal ecosystems. The direct manuring by seabirds at colony locations may strongly influence species richness and biodiversity. The subsequent volatilisation and deposition of NH3 increases the spatial extent of seabird influence on nitrogen cycling in their local ecosystem. As many seabird populations are fluctuating due to changing food supply, climate change or anthropogenic pressures, these factors

  6. MEASUREMENT OF AMMONIA RELEASE FROM SALTSTONE

    SciTech Connect

    Zamecnik, J; Alex Cozzi, A

    2009-01-15

    SRNL was requested by WSRC Waste Solidification Engineering to characterize the release of ammonia from saltstone curing at 95 C by performing experimental testing. These tests were performed with an MCU-type Tank 50H salt simulant containing 0, 50, and 200 mg/L ammonia. The testing program showed that above saltstone made from the 200 mg/L ammonia simulant, the vapor space ammonia concentration was about 2.7 mg/L vapor at 95 C. An upper 95% confidence value for this concentration was found to be 3.9 mg/L. Testing also showed that ammonia was chemically generated from curing saltstone at 95 C; the amount of ammonia generated was estimated to be equivalent to 121 mg/L additional ammonia in the salt solution feed. Even with chemical generation, the ammonia release from saltstone was found to be lower than its release from salt solution only with 200 mg/L ammonia.

  7. Moderate Photoinhibition of Photosystem II Protects Photosystem I from Photodamage at Chilling Stress in Tobacco Leaves.

    PubMed

    Huang, Wei; Yang, Ying-Jie; Hu, Hong; Zhang, Shi-Bao

    2016-01-01

    It has been indicated that photosystem I (PSI) is susceptible to chilling-light stress in tobacco leaves, but the effect of growth light intensity on chilling-induced PSI photoinhibition in tobacco is unclear. We examined the effects of chilling temperature (4°C) associated with moderate light intensity (300 μmol photons m(-2) s(-1)) on the activities of PSI and photosystem II (PSII) in leaves from sun- and shade-grown plants of tobacco (Nicotiana tabacum cv. k326). The sun leaves had a higher activity of alternative electron flow than the shade leaves. After 4 h chilling treatment, the sun leaves showed significantly a higher PSI photoinhibition than the shade leaves. At chilling temperature the sun leaves showed a greater electron flow from PSII to PSI, accompanying with a lower P700 oxidation ratio. When leaves were pre-treated with lincomycin, PSII activity decreased by 42% (sun leaves) and 47% (shade leaves) after 2 h exposure to the chilling-light stress, but PSI activity remained stable during the chilling-light treatment, because the electron flow from PSII to PSI was remarkably depressed. These results indicated that the stronger chilling-induced PSI photoinhibition in the sun leaves was resulted from a greater electron flow from PSII to PSI. Furthermore, moderate PSII photoinhibition depressed electron flow to PSI and then protected PSI activity against further photodamage in chilled tobacco leaves. PMID:26941755

  8. Moderate Photoinhibition of Photosystem II Protects Photosystem I from Photodamage at Chilling Stress in Tobacco Leaves

    PubMed Central

    Huang, Wei; Yang, Ying-Jie; Hu, Hong; Zhang, Shi-Bao

    2016-01-01

    It has been indicated that photosystem I (PSI) is susceptible to chilling-light stress in tobacco leaves, but the effect of growth light intensity on chilling-induced PSI photoinhibition in tobacco is unclear. We examined the effects of chilling temperature (4°C) associated with moderate light intensity (300 μmol photons m-2 s-1) on the activities of PSI and photosystem II (PSII) in leaves from sun- and shade-grown plants of tobacco (Nicotiana tabacum cv. k326). The sun leaves had a higher activity of alternative electron flow than the shade leaves. After 4 h chilling treatment, the sun leaves showed significantly a higher PSI photoinhibition than the shade leaves. At chilling temperature the sun leaves showed a greater electron flow from PSII to PSI, accompanying with a lower P700 oxidation ratio. When leaves were pre-treated with lincomycin, PSII activity decreased by 42% (sun leaves) and 47% (shade leaves) after 2 h exposure to the chilling-light stress, but PSI activity remained stable during the chilling-light treatment, because the electron flow from PSII to PSI was remarkably depressed. These results indicated that the stronger chilling-induced PSI photoinhibition in the sun leaves was resulted from a greater electron flow from PSII to PSI. Furthermore, moderate PSII photoinhibition depressed electron flow to PSI and then protected PSI activity against further photodamage in chilled tobacco leaves. PMID:26941755

  9. Twenty-five ways to raise your chilled-water temperature differential

    SciTech Connect

    Fiorino, D.P.

    1996-11-01

    This paper recommends practical methods of achieving high chilled-water temperature differentials invariable-flow hydronic cooling systems. After high chilled-water temperature differentials are realized, more Btus (J/s) of cooling will be accomplished per gallon (liter) of chilled-water distributed, and pressure losses and pumping energy will decline considerably. Also, water chiller capacities no longer will be limited by maximum evaporator flow rates and chilled-water storage tanks will store many more ton-hours (megajoules) of cooling. This fundamental approach provides significant, enduring improvements in the performance of variable-flow hydronic cooling systems with great leverage.

  10. A Numerical Study of the Direct-Chill Co-Casting of Aluminum Ingots via Fusion™ Technology

    NASA Astrophysics Data System (ADS)

    Baserinia, Amir R.; Caron, Etienne J. F. R.; Wells, Mary A.; Weckman, David C.; Barker, Simon; Gallerneault, Mark

    2013-08-01

    For the last 70 years, direct-chill (DC) casting has been the mainstay of the aluminum industry for the production of monolithic sheet and extruded products. Traditionally, clad aluminum sheet products have been made from separate core and clad DC cast ingots by an expensive roll-bonding process; however, in 2005, Novelis unveiled an innovative variant of the DC casting process called the Fusion™ Technology process that allows the production of multialloy ingots that can be rolled directly into laminated or clad sheet products. Of paramount importance for the successful commercialization of this new technology is a scientific and quantitative understanding of the Fusion™ casting process that will facilitate process optimization and aid in the future development of casting methodology for different alloy combinations and ingot and clad dimensions. In the current study, a numerical steady-state thermofluids model of the Fusion™ Technology casting process was developed and used to simulate the casting of rectangular bimetallic ingots made from the typical brazing sheet combination of AA3003 core clad with an AA4045 aluminum alloy. The analysis is followed by a parametric study of the process. The influence of casting speed and chill-bar height on the steady-state thermal field within the ingot is investigated. According to the criteria developed with the thermofluids model, the AA3003/AA4045 combination of aluminum alloys can be cast successfully with casting speeds up to 2.4 mm s-1. The quality of the metallurgical bond between the core and the clad is decreased for low casting speeds and chill-bar heights >35 mm. These results can be used as a guideline for improving the productivity of the Fusion™ Technology process.

  11. Enzymatic hydrolysis of ammonia-treated rice straw.

    PubMed

    Sulbarán-de-Ferrer, Betzabé; Aristiguieta, Marielena; Dale, Bruce E; Ferrer, Alexis; Ojeda-de-Rodriguez, Graciela

    2003-01-01

    Rice straw pretreated with liquid anhydrous ammonia was hydrolyzed with cellulase, cellobiase, and hemicellulase. Ammonia-processing conditions were 1.5 g of NH3/g of dry matter, 85 degrees C, and several sample moisture contents. There were four ammonia addition time (min)-processing time (min) combinations. Sugars produced were analyzed as reducing sugars (dinitrosalicylic acid method) and by high-performance liquid chromatography. Monomeric sugars increased from 11% in the nontreated rice straw to 61% of theoretical in treated rice straw (79.2% conversion as reducing sugars). Production of monosaccharides was greater at higher moisture content and was processing time dependent. Glucose was the monosaccharide produced in greater amounts, 56.0%, followed by xylose, arabinose, and fructose, with 35.8, 6.6, and 1.4%, respectively. PMID:12721482

  12. Study of removal of ammonia from urine vapor by dual catalyst

    NASA Technical Reports Server (NTRS)

    Budininkas, P.

    1976-01-01

    The feasibility of ammonia removal from urine vapor by a low temperature dual-catalyst system was investigated. The process is based on the initial catalytic oxidation of ammonia present in urine vapor to nitrogen and nitrous oxide, followed by a catalytic decomposition of the nitrous oxide formed into its elements. The most active catalysts for the oxidation of ammonia and for the decomposition of N2O, identified in screening tests, were then combined into dual catalyst systems and tested to establish their overall efficiencies for the removal of ammonia from artificial gas mixtures. Dual catalyst systems capable of ammonia removal from the artificial gas mixtures were then tested with the actual urine vapor produced by boiling untreated urine. A suitable dual catalyst bed arrangement was found that achieved the removal of ammonia and organic carbon, and recovered water of good quality from urine vapor.

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

    PubMed Central

    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. PMID:23362454

  14. Ammonia synthesis for producing supercritical steam in the context of solar thermochemical energy storage

    NASA Astrophysics Data System (ADS)

    Chen, Chen; Aryafar, Hamarz; Warrier, Gopinath; Lovegrove, Keith M.; Lavine, Adrienne S.

    2016-05-01

    In ammonia-based solar thermochemical energy storage systems, the stored energy is released when the hydrogen (H2) and nitrogen (N2) react exothermically to synthesize ammonia (NH3), providing thermal energy to a power block for electricity generation. However, ammonia synthesis has not yet been shown to reach temperatures consistent with the highest performance modern power blocks. Two similar ammonia synthesis reactors with different lengths have been used to study the ammonia synthesis reaction at high temperature and pressure and to begin the process of model improvement and validation. With the longer reactor, supercritical steam with flow rate up to 0.09 g/s has been heated from less than 350°C to ˜650°C. This result shows the technical feasibility of using ammonia-based thermochemical energy storage in a CSP plant with a supercritical steam Rankine cycle power block.

  15. Organic reactivity in liquid ammonia.

    PubMed

    Ji, Pengju; Atherton, John; Page, Michael I

    2012-08-14

    Liquid ammonia is a useful solvent for many organic reactions including aliphatic and aromatic nucleophilic substitution and metal-ion catalysed reactions. The acidity of acids is modified in liquid ammonia giving rise to differences from conventional solvents. The ionisation constants of phenols and carbon acids are the product of those for ion-pair formation and dissociation to the free ions. There is a linear relationship between the pK(a) of phenols and carbon acids in liquid ammonia and those in water of slope 1.68 and 0.7, respectively. Aminium ions exist in their unprotonated free base form in liquid ammonia. The rates of solvolysis and aminolysis by neutral amines of substituted benzyl chlorides in liquid ammonia show little or no dependence upon ring substituents, in stark contrast with the hydrolysis rates of substituted benzyl halides in water which vary 10(7) fold. However, the rates of the reaction of phenoxide ions and amine anions with 4-substituted benzyl chlorides gives a Hammett ρ = 1.1 and 0.93, respectively. The second order rate constants for the substitution of benzyl chlorides by neutral and anionic amines show a single Brønsted β(nuc) = 0.21 whereas those for substituted phenoxide ions generate a Brønsted β(nuc) = 0.40. The rates of aromatic nucleophilic substitution reactions in liquid ammonia are much faster than those in protic solvents indicating that liquid ammonia behaves like a typical dipolar aprotic solvent in its solvent effects on organic reactions. Nitrofluorobenzenes (NFB) readily undergo solvolysis in liquid ammonia but oxygen nucleophiles, such as alkoxide and phenoxide ions, displace the fluorine of 4-NFB in liquid ammonia to give the corresponding substitution product with little or no competing solvolysis product. The Brønsted β(nuc) for the reaction of 4-NFB with para-substituted phenoxides is 0.91, indicative that the decomposition of the Meisenheimer σ-intermediate is rate limiting. The aminolysis of 4-NFB occurs

  16. pH Regulation of ammonia secretion by Colletotrichum gloeosporioides and its effect on appressorium formation and pathogenicity.

    PubMed

    Miyara, Itay; Shafran, Hadas; Davidzon, Maayan; Sherman, Amir; Prusky, Dov

    2010-03-01

    Host-tissue alkalinization via ammonia accumulation is key to Colletotrichum spp. colonization. Using macroarrays carrying C. gloeosporioides cDNAs, we monitored gene expression during the alkalinization process. A set of genes involved in synthesis and catabolism of ammonia accumulation were identified. Expression of NAD(+)-specific glutamate dehydrogenase (GDH2, encoding ammonia synthesis) and the ammonia exporter AMET were induced at pH 4.0 to 4.5. Conversely, ammonia uptake and transcript activation of the ammonia and glutamate importers (MEP and GLT, respectively) and glutamine synthase (GS1) were higher at pH 6.0 to 7.0. Accumulated ammonia in the wild-type mycelium decreased during ambient alkalinization, concurrent with increased GS1 expression. Deltapac1 mutants of C. gloeosporioides, which are sensitive to alkaline pH changes, showed upregulation of the acid-expressed GDH2 and downregulation of the alkaline-expressed GS1, resulting in 60% higher ammonia accumulation inside the mycelium. Deltagdh2 strains of C. gloeosporioides, impaired in ammonia production, showed 85% inhibition in appressorium formation followed by reduced colonization on avocado fruit (Persea americana cv. Fuerte) pericarp, while exogenic ammonia addition restored appressoria formation. Thus the modulation of genes involved in ammonia metabolism and catabolism by C. gloeosporioides is ambient pH-dependent. Aside from its contribution to necrotrophic stages, ammonia accumulation by germinating spores regulates appressorium formation and determines the initiation of biotrophic stages of avocado-fruit colonization by Colletotrichum spp. PMID:20121452

  17. Removal of ammonia from urine vapor by a dual-catalyst system

    NASA Technical Reports Server (NTRS)

    Budininkas, P.

    1977-01-01

    The feasibility of removing ammonia from urine vapor by a low-temperature dual-catalyst system has been demonstrated. The process is based on the catalytic oxidation of ammonia to a mixture of nitrogen, nitrous oxide, and water, followed by a catalytic decomposition of the nitrous oxide into its elements. Potential ammonia oxidation and nitrous oxide decomposition catalysts were first screened with artificial gas mixtures, then tested with the actual urine vapor produced by boiling untreated urine. A suitable dual-catalyst bed arrangement was found that achieved the removal of ammonia and also organic carbon, and recovered water of good quality from urine vapor.

  18. Scale Rules for Macrosegregation during Direct-Chill Casting of Aluminum Alloys

    NASA Astrophysics Data System (ADS)

    Eskin, Dmitry G.; Du, Qiang; Katgerman, Laurens

    2008-05-01

    An analysis of published experimental and numerical results shows that there is a scaling relationship between the magnitude and direction of centerline segregation in direct-chill (DC) cast billets from aluminum alloys and the process parameters, i.e., billet diameter and casting speed. It seems that there is always a range of these process parameters where the centerline segregation is positive, and there is a threshold when the centerline segregation vanishes. Numerical simulations of macrosegregation during DC casting of a binary Al-Cu alloy were performed at different ratios of casting speed and billet diameter. The macrosegregation model takes into account only two mechanisms of macrosegregation, i.e., thermosolutal convection and shrinkage-induced flow. The results of these computer simulations fit well to the dependence obtained using numerous reference data. The results are discussed in terms of the contribution of different mechanisms of macrosegregation and the shape of the billet sump.

  19. Ammonia removal using nitrification and anammox in a single reactor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this work we evaluated the combination of nitrification and anammox bacteria in a single tank to remove ammonia by deammonification process. The deammonification process is a completely autotrophic nitrogen removal approach that eliminates the carbon needs for denitrification. Thus, it can be a p...

  20. AMMONIA-FREE NOx CONTROL SYSTEM

    SciTech Connect

    Song Wu; Zhen Fan; Andrew H. Seltzer; Richard G. Herman

    2006-06-01

    This report describes a novel NOx control system that has the potential to drastically reduce cost, and enhance performance, operation and safety of power plant NOx control. The new system optimizes the burner and the furnace to achieve very low NOx levels and to provide an adequate amount of CO, and uses the CO for reducing NO both in-furnace and over a downstream AFSCR (ammonia-free selective catalytic reduction) reactor. The AF-SCR combines the advantages of the highly successful SCR technology for power plants and the TWC (three-way catalytic converter) widely used on automobiles. Like the SCR, it works in oxidizing environment of combustion flue gas and uses only base metal catalysts. Like the TWC, the AF-SCR removes NO and excess CO simultaneously without using any external reagent, such as ammonia. This new process has been studied in a development program jointed funded by the US Department of Energy and Foster Wheeler. The report outlines the experimental catalyst work performed on a bench-scale reactor, including test procedure, operating conditions, and results of various catalyst formulations. Several candidate catalysts, prepared with readily available transition metal oxides and common substrate materials, have shown over 80-90% removal for both NO and CO in oxidizing gas mixtures and at elevated temperatures. A detailed combustion study of a 400 MWe coal-fired boiler, applying computational fluid dynamics techniques to model boiler and burner design, has been carried out to investigate ways to optimize the combustion process for the lowest NOx formation and optimum CO/NO ratios. Results of this boiler and burner optimization work are reported. The paper further discusses catalyst scale-up considerations and the conceptual design of a 400 MWe size AF-SCR reactor, as well as economics analysis indicating large cost savings of the ammonia-free NOx control process over the current SCR technology.

  1. Ammonia-Free NOx Control System

    SciTech Connect

    Song Wu; Zhen Fan; Andrew H. Seltzer

    2005-06-30

    Research is being conducted under United States Department of Energy (DOE) Contract DEFC26-03NT41865 to develop a new technology to achieve very low levels of NOx emissions from pulverized coal fired boiler systems by employing a novel system level integration between the PC combustion process and the catalytic NOx reduction with CO present in the combustion flue gas. The combustor design and operating conditions will be optimized to achieve atypical flue gas conditions. This approach will not only suppress NOx generation during combustion but also further reduce NOx over a downstream catalytic reactor that does not require addition of an external reductant, such as ammonia.

  2. Ammonia-Free NOx Control System

    SciTech Connect

    Song Wu; Zhen Fan; Andrew H. Seltzer; Richard G. Herman

    2005-03-31

    Research is being conducted under United States Department of Energy (DOE) Contract DE-FC26-03NT41865 to develop a new technology to achieve very low levels of NOx emissions from pulverized coal fired boiler systems by employing a novel system level integration between the PC combustion process and the catalytic NOx reduction with CO present in the combustion flue gas. The combustor design and operating conditions will be optimized to achieve atypical flue gas conditions. This approach will not only suppress NOx generation during combustion but also further reduce NOx over a downstream catalytic reactor that does not require addition of an external reductant, such as ammonia.

  3. Molecular Mechanisms of Renal Ammonia Transport

    PubMed Central

    Weiner, I. David; Hamm, L. Lee

    2015-01-01

    Acid-base homeostasis to a great extent relies on renal ammonia metabolism. In the past several years, seminal studies have generated important new insights into the mechanisms of renal ammonia transport. In particular, the theory that ammonia transport occurs almost exclusively through nonionic NH3 diffusion and NH4+ trapping has given way to a model postulating that a variety of proteins specifically transport NH3 and NH4+ and that this transport is critical for normal ammonia metabolism. Many of these proteins transport primarily H+ or K+ but also transport NH4+. Nonerythroid Rh glycoproteins transport ammonia and may represent critical facilitators of ammonia transport in the kidney. This review discusses the underlying aspects of renal ammonia transport as well as specific proteins with important roles in renal ammonia transport. PMID:17002591

  4. THE FATE AND TRANSPORT OF AMMONIA AT THE LOCAL TO REGIONAL LEVEL

    EPA Science Inventory

    Air quality model results are developed and presented as to where ammonia goes once it is emitted. The ammonia budget is dissected in terms of dry and wet deposition and turbulent and wind transport. The domain of analysis is the eastern U.S. The CMAQ model is used with process ...

  5. Recovery of ammonia from swine manure using gas-permeable membranes: Effect of aeration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gas-permeable membranes can recover ammonia from manure, reducing pollution whilst converting ammonia into ammonium salt fertilizer. The process involves manure pH control to increase ammonium (NH4) recovery rate that is normally carried out using an alkali. In this study a new strategy to avoid the...

  6. Ammonia Emissions from Land-Applied Manure: Environmental and Economic Benefits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia volatilization is a major N loss process for surface-applied manures and urea fertilizers. The lost ammonia is important for both agricultural and non-agricultural ecosystems because it: a) is a direct loss of plant available N to the farmer, b) reduces the N:P ratio in manure, which accele...

  7. Design and Calibration of Chambers for Measuring Ammonia Emissions from Tie-stall Dairy Barns

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dairy barns are thought to emit large amounts of ammonia, which can have detrimental effects on human health and natural ecosystems. In the U.S., relatively little is known about the processes that affect the rate and magnitude of ammonia emissions from dairy barns. The end of a conventional tie-sta...

  8. Development of Small Gas-fired Ammonia Absorption Air Conditioner for Residential Use

    NASA Astrophysics Data System (ADS)

    Sawada, Takashi; Yamamoto, Yoshiaki; Kobayashi, Hirotake; Shimaoka, Takaharu; Kawahara, Michinori; Uedono, Norio

    Due to the global environmental problems, the usage of natural refrigerants, such as water, ammonia, and hydrocarbons, are examined widely. Especially, absorption heat pump system using ammonia and water is penetrated widely for residential use in the U.S. and Europe, because it is easy to make the air-cooled system and to perform with high COP for heating. Authors have been developing an ammonia/water heat pump system for residential use. This system is driven by natural gas and supplies chilled water for cooling and hot water for heating. The results of performance tests indicated 6.8kW for cooling capacity and 10.3kW for heating capacity. And, some indexes which were related the charge of ammonium and the weight of the out-door unit, were compared with the same item of other equipments, such as, gas-fired LiBr absorption air-conditioners and gas engine driven heat pumps for residential use. The objective of this paper is to introduce the specifications and performance test results of the latest model, and to evaluate the performance of this heat pump system.

  9. Seasonal variation in denitrification and dissimilatory nitrate reduction to ammonia process rates and corresponding key functional genes along an estuarine nitrate gradient

    PubMed Central

    Smith, Cindy J.; Dong, Liang F.; Wilson, John; Stott, Andrew; Osborn, A. Mark; Nedwell, David B.

    2015-01-01

    This research investigated spatial-temporal variation in benthic bacterial community structure, rates of denitrification and dissimilatory nitrate reduction to ammonium (DNRA) processes and abundances of corresponding genes and transcripts at three sites—the estuary-head, mid-estuary and the estuary mouth (EM) along the nitrate gradient of the Colne estuary over an annual cycle. Denitrification rates declined down the estuary, while DNRA rates were higher at the estuary head and middle than the EM. In four out of the six 2-monthly time-points, rates of DNRA were greater than denitrification at each site. Abundance of gene markers for nitrate-reduction (nitrate reductase narG and napA), denitrification (nitrite reductase nirS) and DNRA (DNRA nitrite reductase nrfA) declined along the estuary with significant relationships between denitrification and nirS abundance, and DNRA and nrfA abundance. Spatially, rates of denitrification, DNRA and corresponding functional gene abundances decreased along the estuary. However, temporal correlations between rate processes and functional gene and transcript abundances were not observed. PMID:26082763

  10. Biological denitrification process based on the Fe(0)-carbon micro-electrolysis for simultaneous ammonia and nitrate removal from low organic carbon water under a microaerobic condition.

    PubMed

    Deng, Shihai; Li, Desheng; Yang, Xue; Xing, Wei; Li, Jinlong; Zhang, Qi

    2016-11-01

    A combined process between micro-electrolysis and biological denitrification (MEBD) using iron scraps and an activated carbon-based micro-electrolysis carrier was developed for nitrogen removal under a microaerobic condition. The process provided NH4(+)-N and total nitrogen (TN) removal efficiencies of 92.6% and 95.3%, respectively, and TN removal rate of 0.373±0.11kgN/(m(3)d) at corresponding DO of 1.0±0.1mg/L and HRT of 3h, and the optimal pH of 7.6-8.4. High-throughput sequencing analysis verified that dominant classes belonged to β-, α-, and γ-Proteobacteria, and Nitrospira. The dominant genera Hydrogenophaga and Sphaerotilus significantly increased during the operation, covering 13.2% and 6.1% in biofilms attached to the carrier in the middle of the reactor, respectively. Autotrophic denitrification contributed to >80% of the TN removal. The developed MEBD achieved efficient simultaneous nitrification and autotrophic denitrification, presenting significant potential for application in practical low organic carbon water treatment. PMID:27544918

  11. Ammonia toxicity induces glutamine accumulation, oxidative stress and immunosuppression in juvenile yellow catfish Pelteobagrus fulvidraco.

    PubMed

    Li, Ming; Gong, Shiyan; Li, Qing; Yuan, Lixia; Meng, Fanxing; Wang, Rixin

    2016-01-01

    A study was carried to test the response of yellow catfish for 28days under two ammonia concentrations. Weight gain of fish exposure to high and low ammonia abruptly increased at day 3. There were no significant changes in fish physiological indexes and immune responses at different times during 28-day exposure to low ammonia. Fish physiological indexes and immune responses in the treatment of high ammonia were lower than those of fish in the treatment of low ammonia. When fish were exposed to high ammonia, the ammonia concentration in the brain increased by 19-fold on day 1. By comparison, liver ammonia concentration reached its highest level much earlier at hour 12. In spite of a significant increase in brain and liver glutamine concentration, there was no significant change in glutamate level throughout the 28-day period. The total superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione reductase (GR) activities in the brain gradually decreased from hour 0 to day 28. Liver SOD, GPX and GR activities reached the highest levels at hour 12, and then gradually decreased. Thiobarbituric acid reactive substance brain and liver content gradually increased throughout the 28-day period. Lysozyme, acid phosphatase and alkaline phosphatase activities in the liver reached exceptionally low levels after day 14. This study indicated that glutamine accumulation in the brain was not the major cause of ammonia poisoning, the toxic reactive oxygen species is not fully counter acted by the antioxidant enzymes and immunosuppression is a process of gradual accumulation of immunosuppressive factors. PMID:26811908

  12. Ammonia effect on hydrogenotrophic methanogens and syntrophic acetate-oxidizing bacteria.

    PubMed

    Wang, Han; Fotidis, Ioannis A; Angelidaki, Irini

    2015-11-01

    Ammonia-rich substrates can cause inhibition on anaerobic digestion process. Syntrophic acetate-oxidizing bacteria (SAOB) and hydrogenotrophic methanogens are important for the ammonia inhibitory mechanism on anaerobic digestion. The roles and interactions of SAOB and hydrogenotrophic methanogens to ammonia inhibition effect are still unclear. The aim of the current study was to determine the ammonia toxicity levels of various pure strains of SAOB and hydrogenotrophic methanogens. Moreover, ammonia toxicity on the syntrophic-cultivated strains of SAOB and hydrogenotrophic methanogens was tested. Thus, four hydrogenotrophic methanogens (i.e. Methanoculleus bourgensis, Methanobacterium congolense, Methanoculleu thermophilus and Methanothermobacter thermautotrophicus), two SAOB (i.e. Tepidanaerobacter acetatoxydans and Thermacetogenium phaeum) and their syntrophic cultivation were assessed under 0.26, 3, 5 and 7 g NH4 (+)-N L(-1). The results showed that some hydrogenotrophic methanogens were equally, or in some cases, more tolerant to high ammonia levels compared to SAOB. Furthermore, a mesophilic hydrogenotrophic methanogen was more sensitive to ammonia toxicity compared to thermophilic methanogens tested in the study, which is contradicting to the general belief that thermophilic methanogens are more vulnerable to high ammonia loads compared to mesophilic. This unexpected finding underlines the fact that the complete knowledge of ammonia inhibition effect on hydrogenotrophic methanogens is still absent. PMID:26490748

  13. Electrolytic removal of ammonia from aqueous phase by Pt/Ti anode.

    PubMed

    Li, Liang; Huang, Yuanxing; Liu, Yan; Li, Yangyang

    2013-01-01

    This study investigated the mechanism and kinetic modeling of electrolytic degradation of ammonia with Pt/Ti anode. The results show that ammonia oxidation from direct oxidation or indirect oxidation with hydroxyl radicals was slow but can be observed under pH 9 and high initial ammonia concentration of 1,050 mg N L(-1). Indirect oxidation with HOCl was the mechanism for the chloride-mediated electrolytic removal of ammonia. In this process, pH between 3 and 9 had little effect on the ammonia removal rate, but current density (j) and chloride concentration ([Cl(-)]) showed a linear relationship with ammonia removal rate within the range of 3.8-15.4 mA cm(-2) and 30-300 mg L(-1), respectively. The ammonia removal could be described by a pseudo-zero order kinetics with a mathematic equation of k = 0.0003 × [Cl(-)] × j - 0.076. Treatment of the actual wastewater effluent from a secondary clarifier in a local wastewater treatment plant showed an ammonia removal rate of 0.8 mg N L(-1) h(-1) and energy cost of 14 kJ per mg N ammonia. PMID:23752376

  14. Heterogeneous decomposition of indoor ammonia in a photoreactor with TiO2-finished cotton fabrics.

    PubMed

    Dong, Y; Bai, Z; Liu, R; Wang, X; Yan, H; Zhu, T

    2006-07-01

    Addition of urea-based antifreeze admixtures during cement mixing can make it possible to concrete cement in construction of buildings in cold weather. This, however has led to increasing indoor air pollution due to continuous transformation and emission from urea to gaseous ammonia in indoor concrete walls. In order to control ammonia from indoor concrete walls, aqueous dispersion of nano-titanium dioxide (TiO2) was prepared and mixed with silicone additive to establish a treating bath. Cotton fabrics were finished with this treating bath by using pad-dry-cure process and then characterized by X-Ray Diffractometer, Infrared Fourier Transform Spectrometer and Scanning Electron Microscope. The gaseous ammonia was derived from an environmental condition simulated chamber. The heterogeneous decomposition of gaseous ammonia by UV/TiO2 process in an annular photoreactor fixed with the TiO2-coated cotton fabric was studied under various dosages of aqueous nano-TiO2 dispersion, initial ammonia concentration, relative humidity and gas flow rate. A design equation of surface catalytic kinetics was developed for describing the decomposition of ammonia in air streams by UV/TiO2 process at given operating conditions. Experimental results indicated that increasing dosage of aqueous nano-TiO2 dispersion improved the ammonia decomposition of cotton fabric, which was prepared. At a constant temperature of 25 degrees C, ammonia in the air stream was effective removed by decreasing initial ammonia concentration and gas flow rate. For moisture in the range of 15-65%, when the relatively humidity level was increased to 45%, the decomposition of ammonia was remarkably enhanced, and the decomposition of ammonia could be inhibited by excessive moisture. PMID:16894814

  15. Investigation of hygiene aspects during air chilling of poultry carcases using a model rig.

    PubMed

    Allen, V M; Burton, C H; Corry, J E; Mead, G C; Tinker, D B

    2000-12-01

    1. An experimental rig, designed and built to simulate conditions found in commercial poultry chilling systems, was used to investigate the effects of varying air temperature and chilling duration, and the effect of chlorinated water sprays, on the microbial load present on the skin and in the body cavity of freshly eviscerated poultry carcases; deep muscle and skin temperatures were monitored during chilling at three different temperatures. 2. During dry chilling for 2 h, total viable microbe counts (TVC) and counts of coliforms and pseudomonads from the body cavity fell by between half and one log unit; smaller reductions were observed in samples from the breast skin. 3. The situation changed when chlorinated water sprays (50, 100 or 250 ppm available chlorine) were applied for the first hour of chilling; spraying carcases enhanced the reduction in numbers on the skin; the effect was most pronounced with 250 ppm chlorine; conversely in the body cavity, the general effects of sprays was to increase contamination by up to one log unit. 4. There was no evidence that sprays increased the rate of chilling. 5. When carcases were held overnight in the rig at 11 degrees C after chilling, microbe counts on dry-chilled carcases remained stable, but increased on carcases that had been sprayed with chlorinated water. PMID:11201437

  16. 9 CFR 381.66 - Temperatures and chilling and freezing procedures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Temperatures and chilling and freezing... Procedures § 381.66 Temperatures and chilling and freezing procedures. (a) General. Temperatures and... temperature is reduced to 40 °F. or less, as provided in paragraph (b)(2) of this section unless such...

  17. Chilling-Induced Lipid Degradation in Cucumber (Cucumis sativa L. cv Hybrid C) Fruit 1

    PubMed Central

    Parkin, Kirk L.; Kuo, Shu-Jung

    1989-01-01

    Chilling at 4°C in the dark induced lipid degradation in cucumber (Cucumis sativa L.) fruit upon rewarming at 14°C. Rates of ethane evolution by fruits rewarmed after 3 days of chilling were up to four-fold higher than those evolved by unchilled (14°C) fruits (0.02-0.05 picomoles gram fresh weight−1 hour−1). This potentiation of lipid peroxidation occurred prior to irreversible injury (requiring 3 to 7 days of chilling) as indicated by increases in ethylene evolution and visual observations. Decreases in unsaturation of peel tissue glycolipids were observed in fruits rewarmed after 3 days of chilling, indicating the plastids to be the site of the early phases of chilling-induced peroxidation. Losses in unsaturation of tissue phospholipids were first observed only after chilling for 7 days. Phospholipase D activity appeared to be potentiated in fruits rewarmed after 7 days of chilling as indicated by a decrease in phosphatidylcholine (and secondarily phosphatidylethanolamine) with a corresponding increase in phosphatidic acid. These results indicate that lipid peroxidation may have a role in conferring chilling injury. PMID:16666850

  18. Chills in Different Sensory Domains: Frisson Elicited by Acoustical, Visual, Tactile and Gustatory Stimuli

    ERIC Educational Resources Information Center

    Grewe, Oliver; Katzur, Bjorn; Kopiez, Reinhard; Altenmuller, Eckart

    2011-01-01

    "Chills" (frisson manifested as goose bumps or shivers) have been used in an increasing number of studies as indicators of emotions in response to music (e.g., Craig, 2005; Guhn, Hamm, & Zentner, 2007; McCrae, 2007; Panksepp, 1995; Sloboda, 1991). In this study we present evidence that chills can be induced through aural, visual, tactile, and…

  19. A chemical additive to limit potential bacterial contamination in chill tanks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Broiler carcasses with different types and numbers of bacteria are commonly chilled together in an ice water bath which may lead to transfer of unwanted bacteria from carcass to carcass. Historically chill tanks have been chlorinated to help prevent cross contamination and recently other chemical a...

  20. 9 CFR 381.66 - Temperatures and chilling and freezing procedures.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Temperatures and chilling and freezing... Procedures § 381.66 Temperatures and chilling and freezing procedures. (a) General. Temperatures and... temperature is reduced to 40 °F. or less, as provided in paragraph (b)(2) of this section unless such...

  1. 9 CFR 381.66 - Temperatures and chilling and freezing procedures.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Temperatures and chilling and freezing... Procedures § 381.66 Temperatures and chilling and freezing procedures. (a) General. Temperatures and... temperature is reduced to 40 °F. or less, as provided in paragraph (b)(2) of this section unless such...

  2. 9 CFR 381.66 - Temperatures and chilling and freezing procedures.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Temperatures and chilling and freezing... Procedures § 381.66 Temperatures and chilling and freezing procedures. (a) General. Temperatures and... temperature is reduced to 40 °F. or less, as provided in paragraph (b)(2) of this section unless such...

  3. 9 CFR 381.66 - Temperatures and chilling and freezing procedures.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Temperatures and chilling and freezing... Procedures § 381.66 Temperatures and chilling and freezing procedures. (a) General. Temperatures and... temperature is reduced to 40 °F. or less, as provided in paragraph (b)(2) of this section unless such...

  4. TEMPERATURE CONDITIONING ALTERS TRANSCRIPT ABUNDANCE OF GENES RELATED TO CHILLING STRESS IN GRAPEFRUIT.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grapefruit (Citrus paradisi) are susceptible to chilling injury (CI) if held at temperatures below about 10C. Changes in transcript abundance for a number of genes have been correlated with chilling stress in citrus fruit. We tested the hypothesis that conditioning affects transcript abundance of ...

  5. Occurrence of chilling injury in fresh-cut ‘Kent’ mangoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For best visual quality retention of fresh-cut fruits, the preferred storage temperature is about 5 °C, which is considered a chilling temperature for chilling sensitive tropical fruits like mango. Changes in visual and compositional attributes, aroma volatile production, respiration rate, and elect...

  6. Interactive effects of light and chilling on peach flower and leaf budbreak

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Response to chilling temperatures is a critical factor in the suitability of peach cultivars to moderate climates such as that in the southeastern United States. Much of the research on chilling uses cuttings exposed to various treatments and forced under controlled conditions. Light is not genera...

  7. Diversity of low chill peaches from Asia, Brasil, Europe and the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One hundred fifty-five peach (Prunus persica) cultivars, from Asia, Brazil, Europe, and the USA, were examined using eleven SSRs to study the genetic relationships among low chill as compared to high chill peach germplasm. Data was analyzed by NTSYSpc to form a similarity matrix using Nei and Li’s ...

  8. How does music arouse "chills"? Investigating strong emotions, combining psychological, physiological, and psychoacoustical methods.

    PubMed

    Grewe, Oliver; Nagel, Frederik; Kopiez, Reinhard; Altenmüller, Eckart

    2005-12-01

    Music can arouse ecstatic "chill" experiences defined as "goose pimples" and as "shivers down the spine." We recorded chills both via subjects' self-reports and physiological reactions, finding that they do not occur in a reflex-like manner, but as a result of attentive, experienced, and conscious musical enjoyment. PMID:16597800

  9. Maternal Effects Supersede Nuclear Effects Conditioning Chilling Response in Cucumber (Cucumis Sativus L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chilling damage can be a major determinant of yield reduction in cucumber production by acting to alter in sex expression, flowering dates, and plant development. Previous research determined that the ability of cucumber plants to withstand a chilling event (i.e., tolerance and susceptibility) is d...

  10. Ammonia emissions from cattle feeding operations.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia is a colorless gas with an pungent odor that occurs naturally in trace amounts in the atmosphere, where it is the dominant base. Ammonia is produced during the decomposition of livestock manure. There is concern about atmospheric ammonia because of its potential effects on air quality, wat...

  11. 46 CFR 154.1760 - Liquid ammonia.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Liquid ammonia. 154.1760 Section 154.1760 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR....1760 Liquid ammonia. The master shall ensure that no person sprays liquid ammonia into a cargo...

  12. 46 CFR 154.1760 - Liquid ammonia.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Liquid ammonia. 154.1760 Section 154.1760 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR....1760 Liquid ammonia. The master shall ensure that no person sprays liquid ammonia into a cargo...

  13. 46 CFR 154.1760 - Liquid ammonia.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Liquid ammonia. 154.1760 Section 154.1760 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR....1760 Liquid ammonia. The master shall ensure that no person sprays liquid ammonia into a cargo...

  14. 46 CFR 154.1760 - Liquid ammonia.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Liquid ammonia. 154.1760 Section 154.1760 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR....1760 Liquid ammonia. The master shall ensure that no person sprays liquid ammonia into a cargo...

  15. 46 CFR 154.1760 - Liquid ammonia.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Liquid ammonia. 154.1760 Section 154.1760 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR....1760 Liquid ammonia. The master shall ensure that no person sprays liquid ammonia into a cargo...

  16. 27 CFR 21.96 - Ammonia, aqueous.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Ammonia, aqueous. 21.96 Section 21.96 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Ammonia, aqueous. (a) Alkalinity. Strongly alkaline to litmus. (b) Ammonia content. 27 to 30 percent...

  17. Update on cerebral uptake of blood ammonia.

    PubMed

    Sørensen, Michael

    2013-06-01

    Ammonia is believed to play a key role in the development of hepatic encephalopathy (HE) with increased formation of glutamine playing a central role. It has been debated whether blood ammonia enters the brain by passive diffusion and/or active transport by ion-transporters and that changes in blood pH could affect the blood-to-brain transfer of ammonia. It has also been proposed that the permeability-surface area product for ammonia across the blood-brain barrier (PSBBB) should be increased in cirrhosis and HE. In the present paper it is argued that changes in blood pH does not alter PSBBB for ammonia and the question of passive diffusion versus active transport of ammonia remains unresolved. Furthermore, recent studies do not find evidence for increased PSBBB for ammonia in cirrhosis. The main determent for cerebral uptake of blood ammonia (i.e. flux) is the arterial blood ammonia concentration. This means that the only way to protect the brain from hyperammonemia is by lowering blood ammonia, inhibit cerebral uptake of ammonia, or by manipulating cerebral ammonia metabolism so that less glutamine is produced. PMID:23479402

  18. Secondary Cooling in the Direct-Chill Casting of Magnesium Alloy AZ31

    NASA Astrophysics Data System (ADS)

    Caron, E.; Wells, M. A.

    2009-08-01

    Secondary cooling information is critical when modeling the direct-chill (DC) casting process of magnesium alloys. However, accurate data for the heat flux in the secondary cooling zone are scarce, and most reported research is concerned with the DC casting of aluminum alloys. Cooling experiments that simulated the secondary cooling of magnesium AZ31 were conducted in order to observe the influence of various parameters on the different boiling-water heat-transfer phenomena. The heat flux in each boiling regime was quantified as a function of the cooling-water flow rate, water temperature, and initial sample temperature. Equations developed from the cooling experiments could be combined to build “idealized” boiling curves for a given set of DC casting conditions.

  19. Infection-Related Declines in Chill Coma Recovery and Negative Geotaxis in Drosophila melanogaster

    PubMed Central

    Linderman, Jessica A.; Chambers, Moria C.; Gupta, Avni S.; Schneider, David S.

    2012-01-01

    Studies of infection in Drosophila melanogaster provide insight into both mechanisms of host resistance and tolerance of pathogens. However, research into the pathways involved in these processes has been limited by the relatively few metrics that can be used to measure sickness and health throughout the course of infection. Here we report measurements of infection-related declines in flies' performance on two different behavioral assays. D. melanogaster are slower to recover from a chill-induced coma during infection with either Listeria monocytogenes or Streptococcus pneumoniae. L. monocytogenes infection also impacts flies' performance during a negative geotaxis assay, revealing a decline in their rate of climbing as part of their innate escape response after startle. In addition to providing new measures for assessing health, these assays also suggest pathological consequences of and metabolic shifts that may occur over the course of an infection. PMID:23028430

  20. Insights on the development, kinetics, and variation of photoinhibition using chlorophyll fluorescence imaging of a chilled, variegated leaf.

    PubMed

    Hogewoning, Sander W; Harbinson, Jeremy

    2007-01-01

    The effect of chilling on photosystem II (PSII) efficiency was studied in the variegated leaves of Calathea makoyana, in order to gain insight into the causes of chilling-induced photoinhibition. Additionally, a relationship was revealed between (chilling) stress and variation in photosynthesis. Chilling treatments (5 degrees C and 10 degrees C) were performed for different durations (1-7 d) under a moderate irradiance (120 micromol m-2 s-1). The individual leaves were divided into a shaded zone and two illuminated, chilled zones. The leaf tip and sometimes the leaf base were not chilled. Measurements of the dark-adapted Fv/Fm were made on the different leaf zones at the end of the chilling treatment, and then for several days thereafter to monitor recovery. Chilling up to 7 d in the dark did not affect PSII efficiency and visual appearance, whereas chilling in the light caused severe photoinhibition, sometimes followed by leaf necrosis. Photoinhibition increased with the duration of the chilling period, whereas, remarkably, chilling temperature had no effect. In the unchilled leaf tip, photoinhibition also occurred, whereas in the unchilled leaf base it did not. Whatever the leaf zone, photoinhibition became permanent if the mean value dropped below 0.4, although chlorosis and necrosis were associated solely with chilled illuminated tissue. Starch accumulated in the unchilled leaf tip, in contrast to the adjacent chilled irradiated zone. This suggests that photoinhibition was due to a secondary effect in the unchilled leaf tip (sink limitation), whereas it was a direct effect of chilling and irradiance in the chilled illuminated zones. The PSII efficiency and its coefficient of variation showed a unique negative linearity across all leaf zones and different tissue types. The slope of this curve was steeper for chilled leaves than it was for healthy, non-stressed leaves, suggesting that the coefficient of variation may be an important tool for assessing stress in

  1. Hydrogen production using ammonia borane

    SciTech Connect

    Hamilton, Charles W; Baker, R. Thomas; Semelsberger, Troy A; Shrestha, Roshan P

    2013-12-24

    Hydrogen ("H.sub.2") is produced when ammonia borane reacts with a catalyst complex of the formula L.sub.nM-X wherein M is a base metal such as iron, X is an anionic nitrogen- or phosphorus-based ligand or hydride, and L is a neutral ancillary ligand that is a neutral monodentate or polydentate ligand.

  2. Ammonia excretion by Azobacter chroococcum

    SciTech Connect

    Narula, N.; Lakshminarayana, K.; Tauro, P.

    1981-02-01

    In recent years, research has focused attention on the development of biological systems for nitrogen fixation. In this report, two strains of Azotobacter chroococcum are identified which can excrete as much as 45 mg ammonia/ml of the culture broth in a sucrose supplemented synthetic medium.

  3. Stratified storage economically increases capacity and efficiency of campus chilled water system

    SciTech Connect

    Bahnfleth, W.P.; Joyce, W.S.

    1995-03-01

    This article describes how the addition of stratified chilled water storage to the Cornell University campus chilled water system has increased its capacity and efficiency and reduced its operating costs for less than the cost of a conventional chilled water plant expansion. While chilled water storage is not appropriate for all chilled water systems, the experience at Cornell indicates that it can be very cost effective when favorable conditions exist. It should receive serious consideration by owners of large systems who are investigating alternatives for system expansion. The benefits of variable speed chiller operation were found to be considerable. It is hoped that this successful application will stimulate further interest in the development and application of variable speed drive chillers.

  4. An Inexpensive Radiosonde Chilled Mirror Sensor: An Old Technology With New Impact

    NASA Technical Reports Server (NTRS)

    Schmidlin, F. J.; Busalacchi, Antonio J. (Technical Monitor)

    1999-01-01

    The availability of an inexpensive chilled mirror dewpoint sensor has made improved atmospheric relative humidity measurements accessible. Comparisons between the chilled mirror sensor and routine radiosonde sensors have provided new information on the limitation and reliability of the routine measurements. The chilled mirror has observed detailed moisture profiles at cirrus cloud levels when cirrus was not visible, a feature that routine sensors fail to observe. Comparison measurements between the chilled mirror, the carbon resistive (hygristor) and, the capacitive sensors will be discussed. Measurements from three locations (Wallops Island; Andros Island, Bahamas; and Camborne, UK) will be highlighted. It is conceivable that the chilled mirror sensor, when its capability is fully understood, may be sufficiently reliable to serve as a reference.

  5. Warm Root Temperature Mitigates the Effect of Chilling in the Dark on Photosynthesis in Cotton (Gossypium hirsutum) Seedlings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Productivity of warm season crops such as cotton (Gossypium hirsutum L.) can be reduced by untimely episodes of chilling temperature that often occur during the first weeks after planting. We examined the impact of chilling stress on cotton seedlings two weeks after planting by chilling both shoots...

  6. Nondestructive detection of chilling injury in cucumber fruit using hyperspectral imaging with feature selection and supervised classification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chilling injury, as a physiological disorder in cucumbers, occurs after the fruit has been subjected to low temperatures. It is thus desirable to detect chilling injury at early stages and/or remove chilling injured cucumbers during sorting and grading. This research was aimed to apply hyperspectral...

  7. A mass transfer model of ammonia volatilisation from anaerobic digestate

    SciTech Connect

    Whelan, M.J.; Everitt, T.; Villa, R.

    2010-10-15

    Anaerobic digestion (AD) is becoming increasingly popular for treating organic waste. The methane produced can be burned to generate electricity and the digestate, which is high in mineral nitrogen, can be used as a fertiliser. In this paper we evaluate potential losses of ammonia via volatilisation from food waste anaerobic digestate using a closed chamber system equipped with a sulphuric acid trap. Ammonia losses represent a pollution source and, over long periods could reduce the agronomic value of the digestate. Observed ammonia losses from the experimental system were linear with time. A simple non-steady-state partitioning model was developed to represent the process. After calibration, the model was able to describe the behaviour of ammonia in the digestate and in the trap very well. The average rate of volatilisation was approximately 5.2 g N m{sup -2} week{sup -1}. The model was used to extrapolate the findings of the laboratory study to a number of AD storage scenarios. The simulations highlight that open storage of digestate could result in significant losses of ammonia to the atmosphere. Losses are predicted to be relatively minor from covered facilities, particularly if depth to surface area ratio is high.

  8. Ammonia modification of oxide-free Si(111) surfaces

    NASA Astrophysics Data System (ADS)

    Chopra, Tatiana Peixoto; Longo, Roberto C.; Cho, Kyeongjae; Chabal, Yves J.

    2016-08-01

    Amination of surfaces is useful in a variety of fields, ranging from device manufacturing to biological applications. Previous studies of ammonia reaction on silicon surfaces have concentrated on vapor phase rather than wet chemical processes, and mostly on clean Si surfaces. In this work, the interaction of liquid and vapor-phase ammonia is examined on three types of oxide-free surfaces - passivated by hydrogen, fluorine (1/3 monolayer) or chlorine - combining infrared absorption spectroscopy, X-ray photoelectron spectroscopy, and first-principles calculations. The resulting chemical composition highly depends on the starting surface; there is a stronger reaction on both F- and Cl-terminated than on the H-terminated Si surfaces, as evidenced by the formation of Si-NH2. Side reactions can also occur, such as solvent reaction with surfaces, formation of ammonium salt by-products (in the case of 0.2 M ammonia in dioxane solution), and nitridation of silicon (in the case of neat and gas-phase ammonia reactions for instance). Unexpectedly, there is formation of Si-H bonds on hydrogen-free Cl-terminated Si(111) surfaces in all cases, whether vapor phase of neat liquid ammonia is used. The first-principles modeling of this complex system suggests that step-edge surface defects may play a key role in enabling the reaction under certain circumstances, despite the endothermic nature for Si-H bond formation.

  9. Effects of Aesthetic Chills on a Cardiac Signature of Emotionality

    PubMed Central

    Sumpf, Maria; Jentschke, Sebastian; Koelsch, Stefan

    2015-01-01

    Background Previous studies have shown that a cardiac signature of emotionality (referred to as EK, which can be computed from the standard 12 lead electrocardiogram, ECG), predicts inter-individual differences in the tendency to experience and express positive emotion. Here, we investigated whether EK values can be transiently modulated during stimulation with participant-selected music pieces and film scenes that elicit strongly positive emotion. Methodology/Principal Findings The phenomenon of aesthetic chills, as indicated by measurable piloerection on the forearm, was used to accurately locate moments of peak emotional responses during stimulation. From 58 healthy participants, continuous EK values, heart rate, and respiratory frequency were recorded during stimulation with film scenes and music pieces, and were related to the aesthetic chills. EK values, as well as heart rate, increased significantly during moments of peak positive emotion accompanied by piloerection. Conclusions/Significance These results are the first to provide evidence for an influence of momentary psychological state on a cardiac signature of emotional personality (as reflected in EK values). The possibility to modulate ECG amplitude signatures via stimulation with emotionally significant music pieces and film scenes opens up new perspectives for the use of emotional peak experiences in the therapy of disorders characterized by flattened emotionality, such as depression or schizoid personality disorder. PMID:26083383

  10. Flow Analysis on a Limited Volume Chilled Water System

    SciTech Connect

    Zheng, Lin

    2012-07-31

    LANL Currently has a limited volume chilled water system for use in a glove box, but the system needs to be updated. Before we start building our new system, a flow analysis is needed to ensure that there are no high flow rates, extreme pressures, or any other hazards involved in the system. In this project the piping system is extremely important to us because it directly affects the overall design of the entire system. The primary components necessary for the chilled water piping system are shown in the design. They include the pipes themselves (perhaps of more than one diameter), the various fitting used to connect the individual pipes to form the desired system, the flow rate control devices (valves), and the pumps that add energy to the fluid. Even the most simple pipe systems are actually quite complex when they are viewed in terms of rigorous analytical considerations. I used an 'exact' analysis and dimensional analysis considerations combined with experimental results for this project. When 'real-world' effects are important (such as viscous effects in pipe flows), it is often difficult or impossible to use only theoretical methods to obtain the desired results. A judicious combination of experimental data with theoretical considerations and dimensional analysis are needed in order to reduce risks to an acceptable level.

  11. Climate Change Affects Winter Chill for Temperate Fruit and Nut Trees

    PubMed Central

    Luedeling, Eike; Girvetz, Evan H.; Semenov, Mikhail A.; Brown, Patrick H.

    2011-01-01

    Background Temperate fruit and nut trees require adequate winter chill to produce economically viable yields. Global warming has the potential to reduce available winter chill and greatly impact crop yields. Methodology/Principal Findings We estimated winter chill for two past (1975 and 2000) and 18 future scenarios (mid and end 21st century; 3 Global Climate Models [GCMs]; 3 greenhouse gas emissions [GHG] scenarios). For 4,293 weather stations around the world and GCM projections, Safe Winter Chill (SWC), the amount of winter chill that is exceeded in 90% of all years, was estimated for all scenarios using the “Dynamic Model” and interpolated globally. We found that SWC ranged between 0 and about 170 Chill Portions (CP) for all climate scenarios, but that the global distribution varied across scenarios. Warm regions are likely to experience severe reductions in available winter chill, potentially threatening production there. In contrast, SWC in most temperate growing regions is likely to remain relatively unchanged, and cold regions may even see an increase in SWC. Climate change impacts on SWC differed quantitatively among GCMs and GHG scenarios, with the highest GHG leading to losses up to 40 CP in warm regions, compared to 20 CP for the lowest GHG. Conclusions/Significance The extent of projected changes in winter chill in many major growing regions of fruits and nuts indicates that growers of these commodities will likely experience problems in the future. Mitigation of climate change through reductions in greenhouse gas emissions can help reduce the impacts, however, adaption to changes will have to occur. To better prepare for likely impacts of climate change, efforts should be undertaken to breed tree cultivars for lower chilling requirements, to develop tools to cope with insufficient winter chill, and to better understand the temperature responses of tree crops. PMID:21629649

  12. [Effects of chilling stress on antioxidant system and ultrastructure of walnut cultivars].

    PubMed

    Tian, Jing-hua; Wang, Hong-xia; Zhang, Zhi-hua; Gao, Yi

    2015-05-01

    In order to reveal cold hardiness mechanisms and ascertain suitable cold hardiness biochemical indicators of walnut (Juglans regia) , three walnut cultivars ' Hartley' , 'Jinlong 1' and 'Jinlong 2' with strong to weak tolerance of chilling stress, were used to investigate variations of leaf antioxidant enzyme activity and superoxide anion (O2-·) content in one year-old branches under chilling stress at 1 °C in leaf-expansion period. The mesophyll cells ultrastructure of ' Hartley' and 'Jinlong 2' under chilling stress were also observed by transmission electron microscope. The results showed that the superoxide dismutase (SOD) and peroxidase (POD) enzyme activities were the strongest and O2-· content was the lowest in chilling-tolerant cultivar ' Hartley' under chilling stress among the three cultivars. The ultrastructure of the mesophyll cells was stable, and chilling injury symptoms of the leaves were not observed. In chilling-sensitive cultivar 'Jinlong 2' , the SOD, POD and catalase enzyme ( CAT) activities decreased sharply, and the O2-· content was kept at a high level under chilling stress. The ultrastructure of the mesophyll cells was injured obviously at 1 °C∟ for 72 hours. Most of chloroplasts were swollen, and grana lamella became thinner and fewer. A number of chloroplasts envelope and plasma membrane were damaged and became indistinct. At the same time, the edges of some of 'Jinlong 2' young leaves became water-soaked. It was concluded that the ultrastructure stability of mesophyll cells under chilling stress was closely related to walnut cold hardiness. SOD, POD enzyme activities and O2-· content in walnut leaves could be used as biochemical indicators of walnut cold hardiness in leaf-expansion period. There might be a correlation between the damage of cell membrane system and reactive oxygen accumulation under chilling stress. PMID:26571647

  13. Characterization of ammonia volatilization from liquid dairy manure

    NASA Astrophysics Data System (ADS)

    Koirala, Kedar

    Emission of gases, odor, and particulate matters from livestock manure is a major concern because of their potential adverse environmental impacts. For example, ammonia in the air has the potential to: negatively affect animal, human health and environment. Mitigation of ammonia emissions from livestock manure to protect animal and human health, and the environment, in general, is thus an important agenda for livestock producers, engineers, and environmental scientists. Proper understanding of the mechanisms or process of its volatilization from manure is the first step towards designing or formulating appropriate emissions mitigation strategies. This research investigated the effects of suspended solids, anaerobic digestion, and ionic strength on the ammonia (NH3) volatilization mechanism from liquid dairy manure. Experiments were conducted to: (i) assess the role of suspended solids characteristics on ammonia volatilization, (ii) evaluate the impacts of anaerobic digestion on the process governing NH 3 volatilization, and (iii) delineate the influences of suspended solids (SS) and ionic strength (IS) on the ammonia volatilization process from dairy manure. Two key parameters (the ammonia dissociation and the overall mass transfer coefficient (KoL)) that govern ammonia volatilization were evaluated to achieve these objectives. The physical and chemical properties of manure were also evaluated to further elucidate the respective processes. The suspended solids ammoniacal nitrogen adsorption properties did not significantly affect either the ammonium dissociation or the K oL; suggesting that the characteristics of manure suspended solids did not play a significant role in ammonia volatilization from liquid dairy manure. The dissociation of ammonium in anaerobically digested (AD) manure was significantly higher than in the undigested (UD) manure. However, KoL was less in AD manure than in UD manure, while an increase in total ammoniacal nitrogen (TAN) was observed

  14. Effects of liquid ammonia treatment on the physical properties of knit fabric

    NASA Astrophysics Data System (ADS)

    Lee, I. Y.; Kim, S. D.; Hwang, C. S.; Kim, S. R.; Park, S. W.

    2016-07-01

    The cellulosic knit fabric must be treated by NaOH solution in silket process to modify dyeability, luster, physical property, etc. But the silket treated knit fabric has a stiff touch, and must be treated with much of silicone softener. But it has bad durability of laundry. And the silket process has a problem that must discharge a lot of alkaline wastewater. In case of woven fabrics, as an alternative to silket process, liquid ammonia process was developed and this process is eco-friendly because the used ammonia is recovered by 98%. But the knit fabrics are not applicable to the conventional liquid ammonia process because they have selvedge curling problem and are very sensitive to tension. Recently, Korea High Tech Textile Research Institute(Korea) and Lafer SPA(Italy) worked together to develop the new liquid ammonia process for knit fabrics. In the present study, the physical properties of knit fabric after the newly-developed liquid ammonia treatment were investigated. The basic physical properties of knit fabric were measured using the Kawabata evaluation system. In addition, the dyeability, dimensional stability, eco-friendliness were investigated. The results showed that liquid ammonia treatment gave improved physical properties, which can be attributed to fast and uniform swelling, to knit fabric and resulted in a dimensional stability. The knit fabric treated in liquid ammonia showed a darker colour and unique appearance. Above all, the knit fabric treated in liquid ammonia had softer touch and superior gloss than the knit fabric of silket process. The new liquid ammonia process for knit fabrics will become the highest quality standard for knits and will be considered the preferred finish also thanks to eco-friendliness.

  15. Nitrate to ammonia ceramic (NAC) bench scale stabilization study

    SciTech Connect

    Caime, W.J.; Hoeffner, S.L.

    1995-10-01

    Department of Energy (DOE) sites such as the Hanford site, Idaho National Engineering Laboratory (INEL), Savannah River site, Oak Ridge National Laboratory (ORNL) have large quantities of sodium-nitrate based liquid wastes. A process to reduce the nitrates to ammonia has been developed at ORNL. This technology creates a sludge lower in nitrates. This report describes stabilization possibilities of the sludge.

  16. Ammonia recovery from livestock waste using gas permeable membrane technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This presentation shows new methods and systems being developed for reducing ammonia emissions from livestock waste and recovering concentrated liquid nitrogen that could be sold as fertilizer. These systems use gas-permeable membranes as components of new processes to capture and recover the ammoni...

  17. Ammonia recovery from livestock wastewater with gas permeable membranes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This presentation shows new methods and systems being developed for reducing ammonia emissions from livestock waste and recovering concentrated liquid nitrogen that could be sold as fertilizer. These systems use gas-permeable membranes as components of new processes to capture and recover the ammoni...

  18. Electrochemically driven extraction and recovery of ammonia from human urine.

    PubMed

    Luther, Amanda K; Desloover, Joachim; Fennell, Donna E; Rabaey, Korneel

    2015-12-15

    Human urine contains high concentrations of nitrogen, contributing about 75% of the nitrogen in municipal wastewaters yet only 1% of the volume. Source separation of urine produces an ideal waste stream for nitrogen and phosphorus recovery, reducing downstream costs of nutrient treatment at wastewater treatment facilities. We examined the efficiency and feasibility of ammonia extraction and recovery from synthetic and undiluted human urine using an electrochemical cell (EC). EC processing of synthetic urine produced an ammonium flux of 384 ± 8 g N m(-2) d(-1) with a 61 ± 1% current efficiency at an energy input of 12 kWh kg(-1) N removed. EC processing of real urine displayed similar performance, with an average ammonium flux of 275 ± 5 g N m(-2) d(-1) sustained over 10 days with 55 ± 1% current efficiency for ammonia and at an energy input of 13 kWh kg(-1) N removed. With the incorporation of an ammonia stripping and absorption unit into the real urine system, 57 ± 0.5% of the total nitrogen was recovered as ammonium sulfate. A system configuration additionally incorporating stripping of the influent headspace increased total nitrogen recovery to 79% but led to reduced performance of the EC as the urine ammonium concentration decrease. Direct stripping of ammonia (NH3) from urine with no chemical addition achieved only 12% total nitrogen recovery at hydraulic retention times comparable with the EC systems. Our results demonstrate that ammonia can be extracted via electrochemical means at reasonable energy inputs of approximately 12 kWh kg(-1) N. Considering also that the hydrogen generated is worth 4.3 kWh kg(-1) N, the net electrical input for extraction becomes approximately 8 kWh kg(-1) N if the hydrogen can be used. Critical for further development will be the inclusion of a passive means for ammonia stripping to reduce additional energy inputs. PMID:26453942

  19. Ammonia-oxidising archaea--physiology, ecology and evolution.

    PubMed

    Schleper, Christa; Nicol, Graeme W

    2010-01-01

    Nitrification is a microbially mediated process that plays a central role in the global cycling of nitrogen and is also of economic importance in agriculture and wastewater treatment. The first step in nitrification is performed by ammonia-oxidising microorganisms, which convert ammonia into nitrite ions. Ammonia-oxidising bacteria (AOB) have been known for more than 100 years. However, metagenomic studies and subsequent cultivation efforts have recently demonstrated that microorganisms of the domain archaea are also capable of performing this process. Astonishingly, members of this group of ammonia-oxidising archaea (AOA), which was overlooked for so long, are present in almost every environment on Earth and typically outnumber the known bacterial ammonia oxidisers by orders of magnitudes in common environments such as the marine plankton, soils, sediments and estuaries. Molecular studies indicate that AOA are amongst the most abundant organisms on this planet, adapted to the most common environments, but are also present in those considered extreme, such as hot springs. The ecological distribution and community dynamics of these archaea are currently the subject of intensive study by many research groups who are attempting to understand the physiological diversity and the ecosystem function of these organisms. The cultivation of a single marine isolate and two enrichments from hot terrestrial environments has demonstrated a chemolithoautotrophic mode of growth. Both pure culture-based and environmental studies indicate that at least some AOA have a high substrate affinity for ammonia and are able to grow under extremely oligotrophic conditions. Information from the first available genomes of AOA indicate that their metabolism is fundamentally different from that of their bacterial counterparts, involving a highly copper-dependent system for ammonia oxidation and electron transport, as well as a novel carbon fixation pathway that has recently been discovered in

  20. Nitrification resilience and community dynamics of ammonia-oxidizing bacteria with respect to ammonia loading shock in a nitrification reactor treating steel wastewater.

    PubMed

    Cho, Kyungjin; Shin, Seung Gu; Lee, Joonyeob; Koo, Taewoan; Kim, Woong; Hwang, Seokhwan

    2016-08-01

    The aim of this study was to investigate the nitrification resilience pattern and examine the key ammonia-oxidizing bacteria (AOB) with respect to ammonia loading shocks (ALSs) in a nitrification bioreactor treating steel wastewater. The perturbation experiments were conducted in a 4-L bioreactor operated in continuous mode with a hydraulic retention time of 10 d. Three sequential ALSs were given to the bioreactor (120, 180 and 180 mg total ammonia nitrogen (TAN)/L. When the first shock was given, the nitrification process completely recovered after 14 d of further operation. However, the resilience duration was significantly reduced to ∼1 d after the second and third ALSs. In the bioreactor, Nitrosomonas aestuarii dominated the other AOB species, Nitrosomonas europaea and N. nitrosa, throughout the process. In addition, the population of N. aestuarii increased with ammonia utilization following each ALS; i.e., this species responded to acute ammonia overloadings by contributing to ammonia oxidation. This finding suggests that N. aestuarii could be exploited to achieve stable nitrification in industrial wastewaters that contain high concentrations of ammonia. PMID:26896313

  1. Cerebroside C Increases Tolerance to Chilling Injury and Alters Lipid Composition in Wheat Roots

    PubMed Central

    Li, Hong-Xia; Xiao, Yu; Cao, Ling-Ling; Yan, Xu; Li, Cong; Shi, Hai-Yan; Wang, Jian-Wen; Ye, Yong-Hao

    2013-01-01

    Chilling tolerance was increased in seed germination and root growth of wheat seedlings grown in media containing 20 µg/mL cerebroside C (CC), isolated from the endophytic Phyllosticta sp. TG78. Seeds treated with 20 µg/mL CC at 4°C expressed the higher germination rate (77.78%), potential (23.46%), index (3.44) and the shorter germination time (6.19 d); root growth was also significantly improved by 13.76% in length, 13.44% in fresh weight and 6.88% in dry mass compared to controls. During the cultivation process at 4°C for three days and the followed 24 h at 25°C, lipid peroxidation, expressed by malondialdehyde (MDA) content and relative membrane permeability (RMP) was significantly reduced in CC-treated roots; activities of lipoxygenase (LOX), phospholipid C (PLC) and phospholipid D (PLD) were inhibited by 13.62–62.26%, 13.54–63.93% and 13.90–61.17%, respectively; unsaturation degree of fatty acids was enhanced through detecting the contents of CC-induced linoleic acid, linolenic acid, palmitic acid and stearic acid using GC-MS; capacities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were individually increased by 7.69–46.06%, 3.37–37.96%, and −7.00–178.07%. These results suggest that increased chilling tolerance may be due, in part, to the reduction of lipid peroxidation and alternation of lipid composition of roots in the presence of CC. PMID:24058471

  2. Impact of TiO₂ and ZnO nanoparticles at predicted environmentally relevant concentrations on ammonia-oxidizing bacteria cultures under ammonia oxidation.

    PubMed

    Luo, Zhuanxi; Qiu, Zhaozheng; Chen, Zheng; Du Laing, Gijs; Liu, Aifen; Yan, Changzhou

    2015-02-01

    Increased application of titanium dioxide and zinc oxide nanoparticles (nano-TiO2 and nano-ZnO) raises concerns related to their environmental impacts. The effects that such nanoparticles have on environmental processes and the bacteria that carry them out are largely unknown. In this study, ammonia-oxidizing bacteria (AOB) enrichment cultures, grown from surface sediments taken from an estuary wetland in Fujian Province, China, were spiked with nano-TiO2 and nano-ZnO (with an average size of 32 and 43 nm, respectively) at predicted environmentally relevant concentrations (≤2 mg L(-1)) to determine their impacts on ammonia oxidation and the mechanisms involved. Results showed that higher nano-TiO2 concentrations significantly inhibited ammonia oxidation in enrichment cultures. It is noteworthy that the average ammonia oxidation rate was significantly correlated to the Shannon index, the Simpson's index, and AOB abundance. This suggested that ammonia oxidation inhibition primarily resulted from a reduction of AOB biodiversity and abundance. However, AOB biodiversity and abundance as well as the average ammonia oxidation rate were not inhibited by nano-ZnO at predicted environmentally relevant concentrations. Accordingly, an insignificant correlation was established between biodiversity and abundance of the AOB amoA gene and the average ammonia oxidation rate under nano-ZnO treatments. AOB present in samples belonged to the β-Proteobacteria class with an affinity close to Nitrosospira and Nitrosomonas genera. This suggested that identified impacts of nano-TiO2 and nano-ZnO on ammonia oxidation processes can be extrapolated to some extent to natural aquatic environments. Complex impacts on AOB may result from different nanomaterials present in aquatic environments at various ambient conditions. Further investigation on how and to what extent different nanomaterials influence AOB diversity and abundance and their subsequent ammonia oxidation processes is therefore

  3. Music chills: The eye pupil as a mirror to music's soul.

    PubMed

    Laeng, Bruno; Eidet, Lise Mette; Sulutvedt, Unni; Panksepp, Jaak

    2016-08-01

    This study evaluated whether music-induced aesthetic "chill" responses, which typically correspond to peak emotional experiences, can be objectively monitored by degree of pupillary dilation. Participants listened to self-chosen songs versus control songs chosen by other participants. The experiment included an active condition where participants made key presses to indicate when experiencing chills and a passive condition (without key presses). Chills were reported more frequently for self-selected songs than control songs. Pupil diameter was concurrently measured by an eye-tracker while participants listened to each of the songs. Pupil size was larger within specific time-windows around the chill events, as monitored by key responses, than in comparison to pupil size observed during 'passive' song listening. In addition, there was a clear relationship between pupil diameter within the chills-related time-windows during both active and passive conditions, thus ruling out the possibility that chills-related pupil dilations were an artifact of making a manual response. These findings strongly suggest that music chills can be visible in the moment-to-moment changes in the size of pupillary responses and that a neuromodulatory role of the central norepinephrine system is thereby implicated in this phenomenon. PMID:27500655

  4. A chilling sensitive mutant of Arabidopsis with altered steryl-ester metabolism

    SciTech Connect

    Hugly, S.; McCourt, P.; Somerville, C. ); Browse, J. ); Patterson, G.W. )

    1990-07-01

    A chilling-sensitive mutant of Arabidopsis thaliana was isolated and subjected to genetic, physiological, and biochemical analysis. The chilling-sensitive nature of the mutant line is due to a single recessive nuclear mutation at a locus designated chs1. In contrast to wild-type plants, which are not adversely affected by low temperatures, the chs1 mutant is killed by several days of exposure to temperatures below 18{degree}C. Following exposure to chilling temperatures, the mutant displays two common symptoms of chilling injury - leaf chlorosis and electrolyte leakage. In these respects, the physiological response of the mutant to low temperatures mimics the response observed in some naturally occurring chilling sensitive species. The biochemical basis of chilling sensitivity was explored by examining the pattern of incorporation of {sup 14}CO{sub 2} into soluble metabolites and lipids in wild-type and mutant plants. The only difference observed between the mutant and wild type was that following low temperature treatment, the mutant accumulated 10-fold more radioactivity in a specific class of neutral lipids which were identified by a variety of criteria to be steryl-esters. The accumulation of radioactivity in the steryl-ester fraction occurs 24 hours before there is any visible evidence of chilling injury.

  5. Anammox Coupled With Nitrification Impacts a Saline, High Ammonia Groundwater

    NASA Astrophysics Data System (ADS)

    Figueroa, L. A.; Landkamer, L.; Peterson, D. M.; Metzler, D.

    2007-05-01

    High amounts of ammonia (130 to 2200 mg-N/l) in a saline environment (TDS = 10-20 g/l) are present in a groundwater plume adjacent to the Colorado River near Moab, Utah. Ammonia levels sufficient to affect aquatic life have been observed in limited sections of the river adjacent to the site, which has prompted interim treatment efforts. Microcosm studies were performed to assess the potential for microbial transformations of ammonia in the hyporheic zone sediment and the effect of ground/river-water mixing on transformations. Experiments were conducted using sub-riverbed sediment and mixtures of groundwater (290 mg-N/L ammonia) and river water (100%, 50% and 10% plume water) in anaerobic and aerobic environments. Aqueous NH4+, NO2-, NO3-, pH, dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) were monitored over 38 days. Interestingly, the ammonia concentration decreased in all microcosms (29% to 100%) with the highest removal occurring in the oxic microcosms. Total nitrogen removal ranged from 27% to 83%. Three lines of evidence suggest that anammox occurred in the anaerobic microcosms: 1) NH4+ concentrations decreased, 2) little change in DOC occurred and 3) DIC decreased. DIC should increase if denitrification were the dominant process. It is possible that small amounts of O2 diffused into the microcosms, driving some nitrification that supplied NO2- for anammox. In the aerobic microcosms, denitrification or anammox occurred in addition to nitrification because nitrate did not accumulate in general. Again, we believe anammox occurred because of DOC and DIC trends. In the aerobic 10% groundwater microcosm, NO3- accumulated once the ammonia concentration became low and the nitrate level stabilized after the ammonia was gone. This also indicated that anammox was the dominant process because denitrification should not stop due to ammonia depletion. The aerobic microcosms were only agitated twice per week, which would allow the sediments to become

  6. Fluorographene based Ultrasensitive Ammonia Sensor

    PubMed Central

    Tadi, Kiran Kumar; Pal, Shubhadeep; Narayanan, Tharangattu N.

    2016-01-01

    Single molecule detection using graphene can be brought by tuning the interactions via specific dopants. Electrostatic interaction between the most electronegative element fluorine (F) and hydrogen (H) is one of the strong interactions in hydrogen bonding, and here we report the selective binding of ammonia/ammonium with F in fluorographene (FG) resulting to a change in the impedance of the system. Very low limit of detection value of ~0.44 pM with linearity over wide range of concentrations (1 pM–0.1 μM) is achieved using the FG based impedance sensor, andthisscreen printed FG sensor works in both ionized (ammonium) and un-ionized ammonia sensing platforms. The interaction energies of FG and NH3/NH4+ are evaluated using density functional theory calculations and the interactions are mapped. Here FGs with two different amounts of fluorinecontents −~5 atomic% (C39H16F2) and ~24 atomic% (C39H16F12) - are theoretically and experimentally studied for selective, high sensitive and ultra-low level detection of ammonia. Fast responding, high sensitive, large area patternable FG based sensor platform demonstrated here can open new avenues for the development of point-of-care devices and clinical sensors. PMID:27142522

  7. Planar waveguide sensor of ammonia

    NASA Astrophysics Data System (ADS)

    Rogoziński, Roman; Tyszkiewicz, Cuma; Karasiński, Paweł; Izydorczyk, Weronika

    2015-12-01

    The paper presents the concept of forming ammonia sensor based on a planar waveguide structure. It is an amplitude sensor produced on the basis of the multimode waveguide. The technological base for this kind of structure is the ion exchange method and the sol-gel method. The planar multimode waveguide of channel type is produced in glass substrate (soda-lime glass of Menzel-Glaser company) by the selective Ag+↔Na+ ion exchange. On the surface of the glass substrate a porous (~40%) silica layer is produced by the sol-gel method. This layer is sensitized to the presence of ammonia in the surrounding atmosphere by impregnation with Bromocresol Purple (BCP) dye. Therefore it constitutes a sensor layer. Spectrophotometric tests carried out showed about 50% reduction of cross-transmission changes of such sensor layer for a wave λ=593 nm caused by the presence of 25% ammonia water vapor in its ambience. The radiation source used in this type of sensor structure is a light emitting diode LED. The gradient channel waveguide is designed for frontal connection (optical glue) with a standard multimode telecommunications waveguide 62.5/125μm.

  8. Fluorographene based Ultrasensitive Ammonia Sensor

    NASA Astrophysics Data System (ADS)

    Tadi, Kiran Kumar; Pal, Shubhadeep; Narayanan, Tharangattu N.

    2016-05-01

    Single molecule detection using graphene can be brought by tuning the interactions via specific dopants. Electrostatic interaction between the most electronegative element fluorine (F) and hydrogen (H) is one of the strong interactions in hydrogen bonding, and here we report the selective binding of ammonia/ammonium with F in fluorographene (FG) resulting to a change in the impedance of the system. Very low limit of detection value of ~0.44 pM with linearity over wide range of concentrations (1 pM–0.1 μM) is achieved using the FG based impedance sensor, andthisscreen printed FG sensor works in both ionized (ammonium) and un-ionized ammonia sensing platforms. The interaction energies of FG and NH3/NH4+ are evaluated using density functional theory calculations and the interactions are mapped. Here FGs with two different amounts of fluorinecontents ‑~5 atomic% (C39H16F2) and ~24 atomic% (C39H16F12) - are theoretically and experimentally studied for selective, high sensitive and ultra-low level detection of ammonia. Fast responding, high sensitive, large area patternable FG based sensor platform demonstrated here can open new avenues for the development of point-of-care devices and clinical sensors.

  9. Fiber-Optic Ammonia Sensors

    NASA Technical Reports Server (NTRS)

    Carter, Michael T.

    2003-01-01

    Reversible, colorimetric fiber-optic sensors are undergoing development for use in measuring concentrations of ammonia in air at levels relevant to human health [0 to 50 parts per million (ppm)]. A sensor of this type includes an optical fiber that has been modified by replacing a portion of its cladding with a polymer coat that contains a dye that reacts reversibly with ammonia and changes color when it does so. The change in color is measured as a change in the amount of light transmitted from one end of the fiber to the other. Responses are reversible and proportional to the concentration of ammonia over the range from 9 to 175 ppm and in some cases the range of reversibility extends up to 270 ppm. The characteristic time for the response of a sensor to rise from 10 to 90 percent of full scale is about 25 seconds. These sensors are fully operational in pure carbon dioxide and are not adversely affected by humidity. This work was done by Michael T. Carter

  10. Fluorographene based Ultrasensitive Ammonia Sensor.

    PubMed

    Tadi, Kiran Kumar; Pal, Shubhadeep; Narayanan, Tharangattu N

    2016-01-01

    Single molecule detection using graphene can be brought by tuning the interactions via specific dopants. Electrostatic interaction between the most electronegative element fluorine (F) and hydrogen (H) is one of the strong interactions in hydrogen bonding, and here we report the selective binding of ammonia/ammonium with F in fluorographene (FG) resulting to a change in the impedance of the system. Very low limit of detection value of ~0.44 pM with linearity over wide range of concentrations (1 pM-0.1 μM) is achieved using the FG based impedance sensor, andthisscreen printed FG sensor works in both ionized (ammonium) and un-ionized ammonia sensing platforms. The interaction energies of FG and NH3/NH4(+) are evaluated using density functional theory calculations and the interactions are mapped. Here FGs with two different amounts of fluorinecontents -~5 atomic% (C39H16F2) and ~24 atomic% (C39H16F12) - are theoretically and experimentally studied for selective, high sensitive and ultra-low level detection of ammonia. Fast responding, high sensitive, large area patternable FG based sensor platform demonstrated here can open new avenues for the development of point-of-care devices and clinical sensors. PMID:27142522

  11. Physiological and Biochemical Mechanisms of Seed Priming-Induced Chilling Tolerance in Rice Cultivars.

    PubMed

    Hussain, Saddam; Khan, Fahad; Hussain, Hafiz A; Nie, Lixiao

    2016-01-01

    Rice belongs to tropical and subtropical environments and is extremely sensitive to chilling stress particularly during emergence and early stages of seedling development. Seed priming can be a good approach to enhance rice germination and stand establishment under chilling stress. The present study examined the role of different seed priming techniques viz., hydropriming, osmopriming, redox priming, chemical priming, and hormonal priming, in enhancing the chilling tolerance in rice. The most effective reagents and their pre-optimized concentrations based on preliminary experiments were used in this study. Two different rice cultivars were sown under chilling stress (18°C) and normal temperatures (28°C) in separate growth chambers. A non-primed control treatment was also maintained for comparison. Chilling stress caused erratic and delayed germination, poor seedling growth, reduced starch metabolism, and lower respiration rate, while higher lipid peroxidation and hydrogen peroxide accumulation in rice seedlings of both cultivars. Nevertheless, all the seed priming treatments effectively alleviated the negative effects of chilling stress. In addition, seed priming treatments triggered the activities of superoxide dismutase, peroxidase, and catalase, and enhanced the accumulations of glutathione and free proline in rice seedlings, which suggests that these measures help prevent the rice seedlings from chilling induced oxidative stress. Chemical priming with selenium and hormonal priming with salicylic acid remained more effective treatments for both rice cultivars under chilling stress than all other priming treatments. The better performance and greater tolerance of primed rice seedlings was associated with enhanced starch metabolism, high respiration rate, lower lipid peroxidation, and strong antioxidative defense system under chilling stress. PMID:26904078

  12. "On-off" thermoresponsive coating agent containing salicylic acid applied to maize seeds for chilling tolerance.

    PubMed

    Guan, Yajing; Li, Zhan; He, Fei; Huang, Yutao; Song, Wenjian; Hu, Jin

    2015-01-01

    Chilling stress is an important constraint for maize seed establishment in the field. In this study, a type of "on-off" thermoresponsive coating agent containing poly (N-isopropylacrylamide-co-butylmethacrylate) (Abbr. P(NIPAm-co-BMA)) hydrogel was developed to improve the chilling tolerance of coated maize seed. The P(NIPAm-co-BMA) hydrogel was synthesized by free-radical polymerization of N-isopropylacrylamide (NIPAm) and butylmethacrylate (BMA). Salicylic acid (SA) was loaded in the hydrogel as the chilling resistance agent. SA-loaded P(NIPAm-co-BMA) was used for seed film-coating of two maize varieties, Huang C (HC, chilling-tolerant) and Mo17 (chilling-sensitive), to investigate the coated seed germination and seedling growth status under chilling stress. The results showed that the hydrogel obtained a phase transition temperature near 12°C with a NIPAM to MBA weight ratio of 1: 0.1988 (w/w). The temperature of 12°C was considered the "on-off" temperature for chilling-resistant agent release; the SA was released from the hydrogel more rapidly at external temperatures below 12°C than above 12°C. In addition, when seedlings of both maize varieties suffered a short chilling stress (5°C), higher concentrations of SA-loaded hydrogel resulted in increased germination energy, germination percentage, germination index, root length, shoot height, dry weight of roots and shoots and protective enzyme activities and a decreased malondialdehyde content in coated maize seeds compared to single SA treatments. The majority of these physiological and biochemical parameters achieved significant levels compared with the control. Therefore, SA-loaded P(NIPAm-co-BMA), a nontoxic thermoresponsive hydrogel, can be used as an effective material for chilling tolerance in film-coated maize seeds. PMID:25807522

  13. Role of the aquaporin PIP1 subfamily in the chilling tolerance of rice.

    PubMed

    Matsumoto, Tadashi; Lian, Hong-Li; Su, Wei-Ai; Tanaka, Daisuke; Liu, Cheng wei; Iwasaki, Ikuko; Kitagawa, Yoshichika

    2009-02-01

    Although an association between chilling tolerance and aquaporins has been reported, the exact mechanisms involved in this relationship remain unclear. We compared the expression profiles of aquaporin genes between a chilling-tolerant and a low temperature-sensitive rice variety using real-time PCR and identified seven genes that closely correlated with chilling tolerance. Chemical treatment experiments, by which rice plants were induced to lose their chilling tolerance, implicated the PIP1 (plasma membrane intrinsic protein 1) subfamily member genes in chilling tolerance. Of these members, changes in expression of the OsPIP1;3 gene suggested this to be the most closely related to chilling tolerance. Although OsPIP1;3 showed a much lower water permeability than members of the OsPIP2 family, OsPIP1;3 enhanced the water permeability of OsPIP2;2 and OsPIP2;4 when co-expressed with either of these proteins in oocytes. Transgenic rice plants (OE1) overexpressing OsPIP1;3 showed an enhanced level of chilling tolerance and the ability to maintain high OsPIP1;3 expression levels under low temperature treatment, similar to that of chilling-tolerant rice plants. We assume that OsPIP1;3, constitutively overexpressed in the leaf and root of transgenic OE1 plants, interacts with members of the OsPIP2 subfamily, thereby improving the plants' water balance under low temperatures and resulting in the observed chilling tolerance of the plants. PMID:19098326

  14. Physiological and Biochemical Mechanisms of Seed Priming-Induced Chilling Tolerance in Rice Cultivars

    PubMed Central

    Hussain, Saddam; Khan, Fahad; Hussain, Hafiz A.; Nie, Lixiao

    2016-01-01

    Rice belongs to tropical and subtropical environments and is extremely sensitive to chilling stress particularly during emergence and early stages of seedling development. Seed priming can be a good approach to enhance rice germination and stand establishment under chilling stress. The present study examined the role of different seed priming techniques viz., hydropriming, osmopriming, redox priming, chemical priming, and hormonal priming, in enhancing the chilling tolerance in rice. The most effective reagents and their pre-optimized concentrations based on preliminary experiments were used in this study. Two different rice cultivars were sown under chilling stress (18°C) and normal temperatures (28°C) in separate growth chambers. A non-primed control treatment was also maintained for comparison. Chilling stress caused erratic and delayed germination, poor seedling growth, reduced starch metabolism, and lower respiration rate, while higher lipid peroxidation and hydrogen peroxide accumulation in rice seedlings of both cultivars. Nevertheless, all the seed priming treatments effectively alleviated the negative effects of chilling stress. In addition, seed priming treatments triggered the activities of superoxide dismutase, peroxidase, and catalase, and enhanced the accumulations of glutathione and free proline in rice seedlings, which suggests that these measures help prevent the rice seedlings from chilling induced oxidative stress. Chemical priming with selenium and hormonal priming with salicylic acid remained more effective treatments for both rice cultivars under chilling stress than all other priming treatments. The better performance and greater tolerance of primed rice seedlings was associated with enhanced starch metabolism, high respiration rate, lower lipid peroxidation, and strong antioxidative defense system under chilling stress. PMID:26904078

  15. Effect of Light and Chilling Temperatures on Chilling-sensitive and Chilling-resistant Plants. Pretreatment of Cucumber and Spinach Thylakoids in Vivo and in Vitro.

    PubMed

    Garber, M P

    1977-05-01

    The effects of chilling temperatures, in light or dark, on the isolated thylakoids and leaf discs of cucumber (Cucumis sativa L. "Marketer") and spinach (Spinacia oleracea L. "Bloomsdale") were studied. The pretreatment of isolated thylakoids and leaf discs at 4 C in the dark did not affect the phenazine methosulfate-dependent phosphorylation, proton uptake, osmotic response to sucrose, Ca(2+)-dependent ATPase activity, or chlorophyll content. Exposure of cucumber cotyledon discs and isolated thylakoids of cucumber and spinach to 4 C in light resulted in a rapid inactivation of the thylakoids. The sequence of activities or components lost during inactivation (starting with the most sensitive) are: phenazine methosulfate-dependent cyclic phosphorylation, proton uptake, osmotic response to sucrose, Ca(2+)-dependent ATPase activity, and chlorophyll. The rate of loss of proton uptake, osmotic response to sucrose, Ca(2+)-dependent ATPase activity and chlorophyll is similar for isolated cucumber and spinach thylakoids, whereas spinach thylakoids are more resistant to the loss of phenazine methosulfate-dependent phosphorylation. The thylakoids of spinach leaf discs were unaffected by exposure to 4 C in light. The results question whether the extreme resistance of spinach thylakoids treated in vivo is solely a function of the chloroplast thylakoid membranes and establish the validity of using in vitro results to make inferences about cucumber thylakoids treated in vivo at 4 C in light. PMID:16659980

  16. pH-dependent ammonia removal pathways in microbial fuel cell system.

    PubMed

    Kim, Taeyoung; An, Junyeong; Lee, Hyeryeong; Jang, Jae Kyung; Chang, In Seop

    2016-09-01

    In this work, ammonia removal paths in microbial fuel cells (MFCs) under different initial pH conditions (pH 7.0, 8.0, and 8.6) were investigated. At a neutral pH condition (pH 7.0), MFC used an electrical energy of 27.4% and removed 23.3% of total ammonia by electrochemical pathway for 192h. At the identical pH condition, 36.1% of the total ammonia was also removed by the biological path suspected to be biological ammonia oxidation process (e.g., Anammox). With the initial pH increased, the electrochemical removal efficiency decreased to less than 5.0%, while the biological removal efficiency highly increased to 61.8%. In this study, a neutral pH should be maintained in the anode to utilize MFCs for ammonia recovery via electrochemical pathways from wastewater stream. PMID:27090407

  17. A comparison of chilled DI water/ozone and CO{sub 2}-based supercritical fluids as replacements for photoresist-stripping solvents

    SciTech Connect

    Rubin, J.B.; Davenhall, L.B.; Barton, J.; Taylor, C.M.V.; Tiefert, K.

    1998-12-31

    Part of the Hewlett Packard Components Group`s Product Stewardship program is the ongoing effort to investigate ways to eliminate or reduce as much as possible the use of chemical substances from manufacturing processes. Currently used techniques to remove hard-baked photoresists from semiconductor wafers require the use of inorganic chemicals or organic strippers and associated organic solvents. Environmental, health and safety, as well as cost considerations prompted the search for alternative, more environmentally-benign, and cost-effective solutions. Two promising, emerging technologies were selected for evaluation: the chilled DI water/ozone technique and supercritical fluids based on carbon dioxide (CO{sub 2}). Evaluating chilled DI water/ozone shows this process to be effective for positive photoresist removal, but may not be compatible with all metallization systems. Testing of a closed-loop CO{sub 2}-based supercritical CO{sub 2} Resist Remover, or SCORR, at Los Alamos, on behalf of Hewlett-packard, shows that this treatment process is effective in removing photoresists, and is fully compatible with commonly used metallization systems. In this paper, the authors present details on the testing programs conducted with both the chilled DI H{sub 2}O/ozone and SCORR treatment processes.

  18. Monitoring and analysis of a chill storage system

    NASA Astrophysics Data System (ADS)

    Schaetzle, W. J.; Brett, C. E.

    1982-12-01

    Parisian, a major department store in University Mall, Tuscaloosa, Alabama, has a free cooling system installed to provide air conditioning. The system uses a cooling tower during cold weather, below 47 F Wet bulb temperature, to chill water to an average 43 F. The cold water is stored in an unconfined aquifer and recovered as required for air conditioning on an annual basis. This contract provides monitoring of this system to evaluate system performance. Instrumentation for monitoring has been selected and is being installed. Water temperatures and integrated flow entering and leaving the air conditioning cooling coils and the cooling tower are the prime measurements. Power input to all pumps and cooling tower is also measured. In addition, the temperatures leaving and entering the wells and near the bottom of the wells are measured at random intervals. The water levels in the wells are measured at similar times. Store and ambient data are also recorded.

  19. Advances, shortcomings, and recommendations for wind chill estimation.

    PubMed

    Shitzer, Avraham; Tikuisis, Peter

    2012-05-01

    This article discusses briefly the advances made and the remaining short-comings in the "new" wind chill charts adopted in the US and Canada in 2001. A number of indicated refinements are proposed, including the use of whole body models in the computations, verification of heat exchange coefficients by human experiments, reconsideration of "calm" wind conditions, reconsideration of frostbite threshold levels, the inclusion of cold-related pain and numbness in the charts, etc. A dynamic numerical model is applied to compare the effects of wind speeds, on the one hand, and air temperatures, on the other, on the steady-state exposed facial and bare finger temperatures. An apparent asymmetry is demonstrated, favoring the effects of wind speeds over those of air temperatures for an identical final facial temperature. This asymmetry is reversed, however, when SI unit changes in these quantities are considered. PMID:20852897

  20. Advances, shortcomings, and recommendations for wind chill estimation

    NASA Astrophysics Data System (ADS)

    Shitzer, Avraham; Tikuisis, Peter

    2012-05-01

    This article discusses briefly the advances made and the remaining short-comings in the "new" wind chill charts adopted in the US and Canada in 2001. A number of indicated refinements are proposed, including the use of whole body models in the computations, verification of heat exchange coefficients by human experiments, reconsideration of "calm" wind conditions, reconsideration of frostbite threshold levels, the inclusion of cold-related pain and numbness in the charts, etc. A dynamic numerical model is applied to compare the effects of wind speeds, on the one hand, and air temperatures, on the other, on the steady-state exposed facial and bare finger temperatures. An apparent asymmetry is demonstrated, favoring the effects of wind speeds over those of air temperatures for an identical final facial temperature. This asymmetry is reversed, however, when SI unit changes in these quantities are considered.

  1. Thermophilic two-stage dry anaerobic digestion of model garbage with ammonia stripping.

    PubMed

    Yabu, Hironori; Sakai, Chikako; Fujiwara, Tomoko; Nishio, Naomichi; Nakashimada, Yutaka

    2011-03-01

    To avoid the inhibition of methane production by ammonia that occurs during the degradation of garbage, anaerobic digestion with prior ammonia production and subsequent stripping was investigated. In the ammonia production phase, the maximum ammonia concentration was approximately 2800 mg N/kg of total wet sludge in the range of 4 days of sludge retention time, indicating that only 43% of total nitrogen in the model garbage was converted to ammonia. The model garbage from which ammonia was produced and stripped was subjected to semi-continuous thermophilic dry anaerobic digestion over 180 days. The gas yield was in the range of 0.68 to 0.75 Nm(3)/kg volatile solid, and it decreased with the decrease of the sludge retention time. The ammonia-nitrogen concentration in the sludge was kept below 3000 mg N/kg total wet sludge. Microbial community structure analysis revealed that the phylum Firmicutes dominated in the ammonia production, but the community structure changed at different sludge retention times. In dry anaerobic digestion, the dominant bacteria shifted from the phylum Thermotogae to Firmicutes. The dominant archaeon was the genus Methanothermobacter, but the ratio of Methanosarcina increased during the process of dry anaerobic digestion. PMID:21094085

  2. Physiological and Transcriptomic Analyses of the Thermophilic, Aceticlastic Methanogen Methanosaeta thermophila Responding to Ammonia Stress

    PubMed Central

    Kato, Souichiro; Sasaki, Konomi; Watanabe, Kazuya; Yumoto, Isao; Kamagata, Yoichi

    2014-01-01

    The inhibitory effects of ammonia on two different degradation pathways of methanogenic acetate were evaluated using a pure culture (Methanosaeta thermophila strain PT) and defined co-culture (Methanothermobacter thermautotrophicus strain TM and Thermacetogenium phaeum strain PB), which represented aceticlastic and syntrophic methanogenesis, respectively. Growth experiments with high concentrations of ammonia clearly demonstrated that sensitivity to ammonia stress was markedly higher in M. thermophila PT than in the syntrophic co-culture. M. thermophila PT also exhibited higher sensitivity to high pH stress, which indicated that an inability to maintain pH homeostasis is an underlying cause of ammonia inhibition. Methanogenesis was inhibited in the resting cells of M. thermophila PT with moderate concentrations of ammonia, suggesting that the inhibition of enzymes involved in methanogenesis may be one of the major factors responsible for ammonia toxicity. Transcriptomic analysis revealed a broad range of disturbances in M. thermophila PT cells under ammonia stress conditions, including protein denaturation, oxidative stress, and intracellular cation imbalances. The results of the present study clearly demonstrated that syntrophic acetate degradation dominated over aceticlastic methanogenesis under ammonia stress conditions, which is consistent with the findings of previous studies on complex microbial community systems. Our results also imply that the co-existence of multiple metabolic pathways and their different sensitivities to stress factors confer resiliency on methanogenic processes. PMID:24920170

  3. Cryoprotectants protect medaka (Oryzias latipes) embryos from chilling injury.

    PubMed

    Zhang, Qing-Jing; Zhou, Guang-Bin; Wang, Yan-Ping; Fu, Xiang-Wei; Zhu, Shi-En

    2012-01-01

    This study was conducted to investigate the effect of six cryoprotectants (dimethyl sulfoxide (DMSO), glycerol (Gly), methanol (MeOH), ethylene glycol (EG), 1,2-propylene glycol (PG) and N,N-dimethylformamide (DMF) on the survival of medaka (Oryzias lapites) embryos at low temperatures (0 and -5C). Firstly, the embryos at 8 to 16-cell stages were exposed to different concentrations (1 to 4 mol per L) of DMSO, Gly, MeOH, EG, PG and DMF for 40min at 26C. After removal of the cryoprotectants (CPAs), the embryo survivals were assessed by their development into live fries following 9 day of culture. The results showed that the higher concentration of the CPA, the lower survival of the embryos; and that the toxicity of the six CPAs to medaka embryos is in the order of PG < MeOH = DMSO < Gly < EG < DMF (P < 0.05). Secondly, based on the results obtained above, embryos at 8 to 16-cell stages or other stages were exposed to 2 mol per L of PG, MeOH or DMSO for up to 180 min at 0C and up to 80 min at -5C respectively. The 8 to 16-cell embryos treated with MeOH at low temperatures showed highest survival. Thirdly, when embryos at different stages were treated with 2 mol per L of MeOH at -5C for 60 min, 16-somite stage embryos showed highest survival, followed by 4-somite, neurula, 50 percent epiboly, blastula, 32-cell and 8 to 16-cell embryos. These results demonstrated that PG had the lowest toxicity to medaka embryos among the six permeable CPAs at 26C, whereas MeOH showed highest cryoprotective efficiency under chilling conditions and chilling injury decreased gradually with the development of medaka embryos. PMID:22576114

  4. Rapid Chill and Fill of a Liquid Hydrogen Tank Demonstrated

    NASA Technical Reports Server (NTRS)

    Kudlac, Maureen T.

    1999-01-01

    The NASA Lewis Research Center, in conjunction with Boeing North American, has been supporting the High Energy Upper Stage (HEUS) program by performing feasibility studies at Lewis Supplemental Multilayer Insulation Research Facility (SMIRF). These tests were performed to demonstrate the feasibility of chilling and filling a tank with liquid hydrogen in under 5 minutes. The goal of the HEUS program is to release a satellite from the shuttle cargo bay and then use a cryogenic (high-energy) upper stage to allow the satellite to achieve final orbit. Because of safety considerations, the propellant tanks for the upper stage will be launched warm and dry. They will be filled from the shuttle's external tank during the mission phase after the solid rocket boosters have jettisoned and prior to jettison of the external tank. Data from previous shuttle missions have been analyzed to ensure that sufficient propellant would be available in the external tank to fill the propellant tank of the proposed vehicle upper stage. Because of mission time-line considerations, the propellant tanks for the upper stage will have to be chilled down and filled in approximately 5 minutes. An existing uninsulated flight weight test tank was installed inside the vacuum chamber at SMIRF, and the chamber was evacuated to the 10(exp -5) torr range to simulate space vacuum conditions in the cargo bay with the doors open. During prerun operations, the facility liquid hydrogen (LH2) supply piping was prechilled with the vent gas bypassing the test article. The liquid hydrogen supply dewar was saturated at local ambient pressure and then pressurized with ambient temperature gaseous helium to the test pressure. A control system was used to ensure that the liquid hydrogen supply pressure was maintained at the test pressure.

  5. Ammonia plant designers talk of big energy savings

    SciTech Connect

    Axelrod, L.C.

    1980-08-27

    The ammonia plant that Pullman Kellogg has designed for Sherritt-Gordon Mines Ltd. in Alberta will require < 27 million Btu/ton of ammonia, and save $8.10/ton in energy costs because of improvements involving increased pressure in the primary reformer; more efficient use of the heat from the secondary reformer; carbon dioxide recovery by Allied Chemical Corp.'s Selexol process; the reduction of power requirements in the synthesis recycle loop; and the use of a horizontal reactor. C. F. Braun and Co. claims that its Purifier process will require < 25 million Btu/ton, due to the use of excess air in the secondary reformer. C-E Lummus offers a 1500 ton/day plant which, incorporating cryogenic recovery of hydrogen from purge gas and operation at a lower steam-to-carbon ratio, would require only 26 million Btu/ton; Haldor Topsoe Inc. offers a design rated at 26.3 million Btu/ton. According to L. C. Axelrod of Pullman Kellogg, ammonia plant construction will shift to gas-rich areas outside the U.S. and Europe. The 3% of the U.S. natural gas used by the fertilizer industry accounts for > 95% of ammonia feedstock.

  6. Transcriptome Profile Analysis of Breast Muscle Tissues from High or Low Levels of Atmospheric Ammonia Exposed Broilers (Gallus gallus).

    PubMed

    Yi, Bao; Chen, Liang; Sa, Renna; Zhong, Ruqing; Xing, Huan; Zhang, Hongfu

    2016-01-01

    Atmospheric ammonia is a common problem in poultry industry. High concentrations of aerial ammonia cause great harm to broilers' health and production. For the consideration of human health, the limit exposure concentration of ammonia in houses is set at 25 ppm. Previous reports have shown that 25 ppm is still detrimental to livestock, especially the gastrointestinal tract and respiratory tract, but the negative relationship between ammonia exposure and the tissue of breast muscle of broilers is still unknown. In the present study, 25 ppm ammonia in poultry houses was found to lower slaughter performance and breast yield. Then, high-throughput RNA sequencing was utilized to identify differentially expressed genes in breast muscle of broiler chickens exposed to high (25 ppm) or low (3 ppm) levels of atmospheric ammonia. The transcriptome analysis showed that 163 genes (fold change ≥ 2 or ≤ 0.5; P-value < 0.05) were differentially expressed between Ammonia25 (treatment group) and Ammonia3 (control group), including 96 down-regulated and 67 up-regulated genes. qRT-PCR analysis validated the transcriptomic results of RNA sequencing. Gene Ontology (GO) functional annotation analysis revealed potential genes, processes and pathways with putative involvement in growth and development inhibition of breast muscle in broilers caused by aerial ammonia exposure. This study facilitates understanding of the genetic architecture of the chicken breast muscle transcriptome, and has identified candidate genes for breast muscle response to atmospheric ammonia exposure. PMID:27611572

  7. Maximum production of fermentable sugars from barley straw using optimized soaking in aqueous ammonia (SAA) pretreatment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soaking in aqueous ammonia (SAA) pretreatment was investigated to improve enzymatic digestibility and consequently to increase total fermentable sugar production from barley straw. Various effects of pretreatment process parameters, such as reaction temperature, reaction time, solid:liquid ratio, an...

  8. Polyaniline-based optical ammonia detector

    DOEpatents

    Duan, Yixiang; Jin, Zhe; Su, Yongxuan

    2002-01-01

    Electronic absorption spectroscopy of a polyaniline film deposited on a polyethylene surface by chemical oxidation of aniline monomer at room temperature was used to quantitatively detect ammonia gas. The present optical ammonia gas detector was found to have a response time of less than 15 s, a regeneration time of less than 2 min. at room temperature, and a detection limit of 1 ppm (v/v) for ammonia, with a linear dynamic range from 180 ppm to 18,000 ppm.

  9. Adsorption of ammonia on multilayer iron phthalocyanine

    SciTech Connect

    Isvoranu, Cristina; Knudsen, Jan; Ataman, Evren; Andersen, Jesper N.; Schnadt, Joachim; Schulte, Karina; Wang Bin; Bocquet, Marie-Laure

    2011-03-21

    The adsorption of ammonia on multilayers of well-ordered, flat-lying iron phthalocyanine (FePc) molecules on a Au(111) support was investigated by x-ray photoelectron spectroscopy. We find that the electron-donating ammonia molecules coordinate to the metal centers of iron phthlalocyanine. The coordination of ammonia induces changes of the electronic structure of the iron phthalocyanine layer, which, in particular, lead to a modification of the FePc valence electron spin.

  10. Cold Cracking Development in AA7050 Direct Chill-Cast Billets under Various Casting Conditions

    NASA Astrophysics Data System (ADS)

    Lalpoor, M.; Eskin, D. G.; Katgerman, L.

    2010-09-01

    Cold cracking is a potentially catastrophic phenomenon in direct chill (DC) casting of 7 xxx series aluminum alloys that leads to safety hazards and loss of production. The relatively low thermal conductivity and wide solidification temperature range in these alloys results in accumulation of residual thermal stress under nonuniform cooling conditions of the billets. In addition, such alloys show a severe loss in ductility below a critical temperature of 573 K (300 °C). This brittleness along with high stress concentration at the tips of voids and microcracks can lead to catastrophic failure. Casting process parameters affect the magnitude and distribution of stresses in the billet and increase the susceptibility of the material to cold cracking. In order to investigate the effect of casting process parameters such as casting speed, billet size, and water flow rate, thermomechanical simulations were applied using ALSIM5 casting simulation software. Among the studied casting process parameters, the increased billet size and high casting speed resulted in the most dramatic increase in residual stress level. Critical crack sizes that led to catastrophic failure were also calculated and are reported against process parameters.

  11. A multiphysics and multiscale model for low frequency electromagnetic direct-chill casting

    NASA Astrophysics Data System (ADS)

    Košnik, N.; Guštin, A. Z.; Mavrič, B.; Šarler, B.

    2016-03-01

    Simulation and control of macrosegregation, deformation and grain size in low frequency electromagnetic (EM) direct-chill casting (LFEMC) is important for downstream processing. Respectively, a multiphysics and multiscale model is developed for solution of Lorentz force, temperature, velocity, concentration, deformation and grain structure of LFEMC processed aluminum alloys, with focus on axisymmetric billets. The mixture equations with lever rule, linearized phase diagram, and stationary thermoelastic solid phase are assumed, together with EM induction equation for the field imposed by the coil. Explicit diffuse approximate meshless solution procedure [1] is used for solving the EM field, and the explicit local radial basis function collocation method [2] is used for solving the coupled transport phenomena and thermomechanics fields. Pressure-velocity coupling is performed by the fractional step method [3]. The point automata method with modified KGT model is used to estimate the grain structure [4] in a post-processing mode. Thermal, mechanical, EM and grain structure outcomes of the model are demonstrated. A systematic study of the complicated influences of the process parameters can be investigated by the model, including intensity and frequency of the electromagnetic field. The meshless solution framework, with the implemented simplest physical models, will be further extended by including more sophisticated microsegregation and grain structure models, as well as a more realistic solid and solid-liquid phase rheology.

  12. Ammonia removal by sweep gas membrane distillation.

    PubMed

    Xie, Zongli; Duong, Tuan; Hoang, Manh; Nguyen, Cuong; Bolto, Brian

    2009-04-01

    Wastewater containing low levels of ammonia (100 mg/L) has been simulated in experiments with sweep gas membrane distillation at pH 11.5. The effects of feed temperature, gas flow rate and feed flow rate on ammonia removal, permeate flux and selectivity were investigated. The feed temperature is a crucial operating factor, with increasing feed temperature increasing the permeate flux significantly, but reducing the selectivity. The best-performing conditions of highest temperature and fastest gas flow rate resulted in 97% removal of the ammonia, to give a treated water containing only 3.3 mg/L of ammonia. PMID:19195677

  13. A baseline study of atmospheric ammonia concentration and fluxes for forest

    NASA Astrophysics Data System (ADS)

    Hansen, K.; Boegh, E.; Hornsby, K. E.; Pryor, S. C.; Sørensen, L. L.

    2014-12-01

    Natural ammonia emissions are difficult to address because most measurement sites are influenced by nearby anthropogenic ammonia sources. Furthermore, measuring the net exchange of ammonia is challenging due to bi-directionality of the flux and the high reactivity of ammonia. In this study we present two months of half-hourly ammonia fluxes and concentrations measured above the remote forest site Morgan-Monroe State Forest (MMSF) in the central Midwest in USA. Measurements are conducted during the late summer and autumn 2013 using the Relaxed Eddy Accumulation Method with the purpose is to quantify the baseline concentration and exchange of ammonia in a natural forest ecosystem and to understand the controlling processes. Combined with additional ammonia studies for MMSF a seasonal baseline of the ammonia concentration above the forest of spring = 0.39±0.39, summer = 0.30±0.39, autumn = 0.20±0.26, and winter = 0.26±0.1 μg m-3 was concluded. The mean concentration of ammonia measured in this study was 0.23 μg m-3 but shorter periods with concentration higher than 1 μg m-3 were also seen. The fluxes were mainly upward (emission) of up to 0.11 μg m-2 s-1, however, when the atmospheric concentration was higher, downward fluxes (deposition) up to -0.07 μg m-2 s-1 occurred. Air mass back trajectories from the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model did not identify any specific source area causing the higher ammonia concentrations measured affirming that the atmospheric ammonia is surface controlled. The largest fluxes was found shortly after rain events indication that the humidity of the forest ecosystem in crucial in controlling both deposition and emission of atmospheric ammonia. Measurements of size resolved aerosol concentrations and nitric acid gas concentrations and fluxes indicated that gas-particle phase partitioning occurred and influenced the exchange of ammonia. At last, a clear diurnal pattern in the ammonia

  14. Mathematical Modeling of Ammonia Electro-Oxidation on Polycrystalline Pt Deposited Electrodes

    NASA Astrophysics Data System (ADS)

    Diaz Aldana, Luis A.

    The ammonia electrolysis process has been proposed as a feasible way for electrochemical generation of fuel grade hydrogen (H2). Ammonia is identified as one of the most suitable energy carriers due to its high hydrogen density, and its safe and efficient distribution chain. Moreover, the fact that this process can be applied even at low ammonia concentration feedstock opens its application to wastewater treatment along with H 2 co-generation. In the ammonia electrolysis process, ammonia is electro-oxidized in the anode side to produce N2 while H2 is evolved from water reduction in the cathode. A thermodynamic energy requirement of just five percent of the energy used in hydrogen production from water electrolysis is expected from ammonia electrolysis. However, the absence of a complete understanding of the reaction mechanism and kinetics involved in the ammonia electro-oxidation has not yet allowed the full commercialization of this process. For that reason, a kinetic model that can be trusted in the design and scale up of the ammonia electrolyzer needs to be developed. This research focused on the elucidation of the reaction mechanism and kinetic parameters for the ammonia electro-oxidation. The definition of the most relevant elementary reactions steps was obtained through the parallel analysis of experimental data and the development of a mathematical model of the ammonia electro-oxidation in a well defined hydrodynamic system, such as the rotating disk electrode (RDE). Ammonia electro-oxidation to N 2 as final product was concluded to be a slow surface confined process where parallel reactions leading to the deactivation of the catalyst are present. Through the development of this work it was possible to define a reaction mechanism and values for the kinetic parameters for ammonia electro-oxidation that allow an accurate representation of the experimental observations on a RDE system. Additionally, the validity of the reaction mechanism and kinetic parameters

  15. Alleviation of postharvest chilling injury of tomato fruit by salicylic acid treatment.

    PubMed

    Aghdam, Morteza Soleimani; Asghari, Mohammadreza; Khorsandi, Orojali; Mohayeji, Mehdi

    2014-10-01

    Tomato fruit at the mature green stage were treated with salicylic acid at different concentration (0, 1 and 2 mM) and analyzed for chilling injury (CI), electrolyte leakage (EL), malondialdehyde (MDA) and proline contents and phospholipase D (PLD) and lipoxygenase (LOX) activities during cold storage. PLD and LOX activities were significantly reduced by salicylic acid treatment. Compared with the control fruit, salicylic acid treatment alleviated chilling injury, reduced electrolyte leakage, malondialdehyde content and increased proline content. Our result suggest that the reduce activity of PLD and LOX, by salicylic acid may be a chilling tolerance strategy in tomato fruit. Inhibition of PLD and LOX activity during low temperature storage could ameliorate chilling injury and oxidation damage and enhance membrane integrity in tomato fruit. PMID:25328231

  16. Aesthetic Chills: Knowledge-Acquisition, Meaning-Making, and Aesthetic Emotions.

    PubMed

    Schoeller, Felix; Perlovsky, Leonid

    2016-01-01

    This article addresses the relation between aesthetic emotions, knowledge-acquisition, and meaning-making. We briefly review theoretical foundations and present experimental data related to aesthetic chills. These results suggest that aesthetic chills are inhibited by exposing the subject to an incoherent prime prior to the chill-eliciting stimulation and that a meaningful prime makes the aesthetic experience more pleasurable than a neutral or an incoherent one. Aesthetic chills induced by narrative structures seem to be related to the pinnacle of the story, to have a significant calming effect and subjects describe a strong empathy for the characters. We discuss the relation between meaning-making and aesthetic emotions at the psychological, physiological, narratological, and mathematical levels and propose a series of hypotheses to be tested in future research. PMID:27540366

  17. Aesthetic Chills: Knowledge-Acquisition, Meaning-Making, and Aesthetic Emotions

    PubMed Central

    Schoeller, Felix; Perlovsky, Leonid

    2016-01-01

    This article addresses the relation between aesthetic emotions, knowledge-acquisition, and meaning-making. We briefly review theoretical foundations and present experimental data related to aesthetic chills. These results suggest that aesthetic chills are inhibited by exposing the subject to an incoherent prime prior to the chill-eliciting stimulation and that a meaningful prime makes the aesthetic experience more pleasurable than a neutral or an incoherent one. Aesthetic chills induced by narrative structures seem to be related to the pinnacle of the story, to have a significant calming effect and subjects describe a strong empathy for the characters. We discuss the relation between meaning-making and aesthetic emotions at the psychological, physiological, narratological, and mathematical levels and propose a series of hypotheses to be tested in future research. PMID:27540366

  18. Ammonia-Free NOx Control System

    SciTech Connect

    Zhen Fan; Song Wu; Richard G. Herman

    2004-06-30

    Research is being conducted under United States Department of Energy (DOE) Contract DEFC26-03NT41865 to develop a new technology to achieve very low levels of NOx emissions from pulverized coal fired boiler systems by employing a novel system level integration between the PC combustion process and the catalytic NOx reduction with CO present in the combustion flue gas. The combustor design and operating conditions will be optimized to achieve atypical flue gas conditions. This approach will not only suppress NOx generation during combustion but also further reduce NOx over a downstream catalytic reactor that does not require addition of an external reductant, such as ammonia. This report describes the work performed during the April 1 to June 30, 2004 time period.

  19. Ammonia-Free NOx Control System

    SciTech Connect

    Song Wu; Zhen Fan; Andrew H. Seltzer

    2005-09-30

    Research is being conducted under United States Department of Energy (DOE) Contract DEFC26-03NT41865 to develop a new technology to achieve very low levels of NOx emissions from pulverized coal fired boiler systems by employing a novel system level integration between the PC combustion process and the catalytic NOx reduction with CO present in the combustion flue gas. The combustor design and operating conditions will be optimized to achieve atypical flue gas conditions. This approach will not only suppress NOx generation during combustion but also further reduce NOx over a downstream catalytic reactor that does not require addition of an external reductant, such as ammonia. This report describes the work performed during the July 1 to September 30, 2005 time period.

  20. Ammonia-Free NOx Control System

    SciTech Connect

    S. Wu; Z. Fan; R. Herman

    2004-03-31

    Research is being conducted under United States Department of Energy (DOE) Contract DEFC26-03NT41865 to develop a new technology to achieve very low levels of NOx emissions from pulverized coal fired boiler systems by employing a novel system level integration between the PC combustion process and the catalytic NOx reduction with CO present in the combustion flue gas. The combustor design and operating conditions will be optimized to achieve atypical flue gas conditions. This approach will not only suppress NOx generation during combustion but also further reduce NOx over a downstream catalytic reactor that does not require addition of an external reductant, such as ammonia. This report describes the work performed during the January 1 to March 31, 2004 time period.

  1. Ammonia-Free NOx Control System

    SciTech Connect

    Song Wu; Zhen Fan; Richard G. Herman

    2004-12-31

    Research is being conducted under United States Department of Energy (DOE) Contract DEFC26-03NT41865 to develop a new technology to achieve very low levels of NOx emissions from pulverized coal fired boiler systems by employing a novel system level integration between the PC combustion process and the catalytic NOx reduction with CO present in the combustion flue gas. The combustor design and operating conditions will be optimized to achieve atypical flue gas conditions. This approach will not only suppress NOx generation during combustion but also further reduce NOx over a downstream catalytic reactor that does not require addition of an external reductant, such as ammonia. This report describes the work performed during the October 1 to December 30, 2004 time period.

  2. Ammonia-Free NOx Control System

    SciTech Connect

    Song Wu; Zhen Fan; Andrew H. Seltzer; Richard G. Herman

    2004-09-30

    Research is being conducted under United States Department of Energy (DOE) Contract DEFC26-03NT41865 to develop a new technology to achieve very low levels of NOx emissions from pulverized coal fired boiler systems by employing a novel system level integration between the PC combustion process and the catalytic NOx reduction with CO present in the combustion flue gas. The combustor design and operating conditions will be optimized to achieve atypical flue gas conditions. This approach will not only suppress NOx generation during combustion but also further reduce NOx over a downstream catalytic reactor that does not require addition of an external reductant, such as ammonia. This report describes the work performed during the July 1 to September 30, 2004 time period.

  3. Atmospheric amines and ammonia measured with a Chemical Ionization Mass Spectrometer (CIMS)

    NASA Astrophysics Data System (ADS)

    You, Y.; Kanawade, V. P.; de Gouw, J. A.; Guenther, A. B.; Madronich, S.; Sierra-Hernández, M. R.; Lawler, M.; Smith, J. N.; Takahama, S.; Ruggeri, G.; Koss, A.; Olson, K.; Baumann, K.; Weber, R. J.; Nenes, A.; Guo, H.; Edgerton, E. S.; Porcelli, L.; Brune, W. H.; Goldstein, A. H.; Lee, S.-H.

    2014-06-01

    We report ambient measurements of amines and ammonia with a~fast response chemical ionization mass spectrometer (CIMS) in a southeastern US forest in Alabama and a~moderately polluted Midwestern site during the summer. In the Alabama forest, mostly C3-amines (from pptv to tens of pptv) and ammonia (up to 2 ppbv) were detected on a daily basis. C3-amines and ammonia showed similar diurnal trends and temperature and wind direction dependences, and were not associated with transported CO and SO2 plumes. Consistent with temperature dependences, amine and ammonia in the gas and aerosol phases showed opposite diurnal trends, indicating gas-to-particle partitioning of amines and ammonia. Temperature dependences also imply reversible processes of amines and ammonia evaporation from soil surfaces in daytime and deposition of amines and ammonia to soil surfaces at nighttime. Various amines (C1-C6) at the pptv level were observed in the transported biomass burning plumes, showing that biomass burning can be a substantial source of amines in the Southeast US. At the moderately polluted Kent site, higher concentrations of amines (C1-C6, from pptv to tens of pptv) and ammonia (up to 6 ppbv) were detected. Diurnal variations of C1- to C3-amines and ammonia were correlated with the ambient temperature. C4- to C6-amines showed abrupt increases during the nighttime, suggesting that they were emitted from local sources. These abundant amines and ammonia may in part explain the frequent new particle formation events reported from Kent. Lower amine concentrations at the rural forested site highlight the importance of constraining anthropogenic sources of amines.

  4. Atmospheric Amines and Ammonia Measured with a Chemical Ionization Mass Spectrometer (CIMS)

    SciTech Connect

    You, Y.; Kanawade, V. P.; de Gouw, J. A.; Guenther, Alex B.; Madronich, Sasha; Sierra-Hernandez, M. R.; Lawler, M.; Smith, James N.; Takahama, S.; Ruggeri, G.; Koss, A.; Olson, K.; Baumann, K.; Weber, R. J.; Nenes, A.; Guo, H.; Edgerton, Eric S.; Porcelli, L.; Brune, W. H.; Goldstein, Allen H.; Lee, S.-H

    2014-11-19

    We report ambient measurements of amines and ammonia with a fast response chemical ionization mass spectrometer (CIMS) in a Southeastern U.S. forest in Alabama and a moderately polluted Midwestern site during the summer. In the Alabama forest, mostly C3-amines (from pptv to tens of pptv) and ammonia (up to 2 ppbv) were detected on a daily basis. C3-amines and ammonia showed similar diurnal trends and temperature and wind direction dependences, and were not associated with transported CO and SO2 plumes. Consistent with temperature dependences, amine and ammonia in the gas and aerosol phases showed opposite diurnal trends, indicating gas-to-particle partitioning of amines and ammonia. Temperature dependences also imply reversible processes of amines and ammonia evaporation from soil surfaces in daytime and deposition of amines and ammonia to soil surfaces at nighttime. Various amines (C1-C6) at the pptv level were observed in the transported biomass burning plumes, showing that biomass burning can be a substantial source of amines in the Southeast U.S. At the moderately polluted Kent site, higher concentrations of amines (C1-C6, from pptv to tens of pptv) and ammonia (up to 6 ppbv) were detected. Diurnal variations of C1- to C3-amines and ammonia were correlated with the ambient temperature. C4- to C6-amines showed abrupt increases during the nighttime, suggesting that they were emitted from local sources. These abundant amines and ammonia may in part explain the frequent new particle formation events reported from Kent. Lower amine concentrations at the rural forested site highlight the importance of constraining anthropogenic sources of amines.

  5. Dormancy release and flowering time in Ziziphus jujuba Mill., a "direct flowering" fruit tree, has a facultative requirement for chilling.

    PubMed

    Meir, Michal; Ransbotyn, Vanessa; Raveh, Eran; Barak, Simon; Tel-Zur, Noemi; Zaccai, Michele

    2016-03-15

    In deciduous fruit trees, the effect of chilling on flowering has mostly been investigated in the "indirect flowering" group, characterized by a period of rest between flower bud formation and blooming. In the present study, we explored the effects of chilling and chilling deprivation on the flowering of Ziziphus jujuba, a temperate deciduous fruit tree belonging to the "direct flowering" group, in which flower bud differentiation, blooming and fruit development occur after dormancy release, during a single growing season. Dormancy release, vegetative growth and flowering time in Z. jujuba cv. Ben-Li were assessed following several treatments of chilling. Chilling treatments quantitatively decreased the timing of vegetative bud dormancy release, thereby accelerating flowering, but had no effect on the time from dormancy release to flowering. Trees grown at a constant temperature of 25°C, without chilling, broke dormancy and flowered, indicating the facultative character of chilling in this species. We measured the expression of Z. jujuba LFY and AP1 homologues (ZjLFY and ZjAP1). Chilling decreased ZjLFY expression in dormant vegetative buds but had no effect on ZjAP1expression, which reached peak expression before dormancy release and at anthesis. In conclusion, chilling is not obligatory for dormancy release of Z. jujuba cv. Ben-Li vegetative buds. However, the exposure to chilling during dormancy does accelerate vegetative bud dormancy release and flowering. PMID:26949231

  6. Water Status Related Root-to-Shoot Communication Regulates the Chilling Tolerance of Shoot in Cucumber (Cucumis sativus L.) Plants

    PubMed Central

    Zhang, Zi-Shan; Liu, Mei-Jun; Gao, Hui-Yuan; Jin, Li-Qiao; Li, Yu-Ting; Li, Qing-Ming; Ai, Xi-Zhen

    2015-01-01

    Although root-to-shoot communication has been intensively investigated in plants under drought, few studies have examined root-to-shoot communication under chilling. Here we explored whether root-to-shoot communication contributes to the chilling-light tolerance of cucumber shoots and clarified the key signal involves in this communication. After leaf discs chilling-light treatment, the photoinhibitions of Photosystem I (PSI) and Photosystem II (PSII) were similar in leaf discs of two cucumber varieties (JY-3 and JC-4). When the whole plants, including roots, were chilled under light, the photosynthetic performances in JC-4 leaves decreased more seriously than that in JY-3 leaves. However, when the water status of leaves was maintained by warming roots or floating the attached leaves on water, the PSII activity and amount of PSI in the leaves of the two varieties were similar after chilling-light treatment. In addition, the differences of PSII activities and amount of PSI between the two varieties under whole plant chilling-light treatment were independent of ABA pretreatment. Above results indicate that (1) the better water status in leaves under chilling contributes to the higher chilling tolerance of JY-3; (2) the water status, rather than an ABA signal, dominates root-to-shoot communication under chilling and the chilling tolerance of cucumber shoot. PMID:26471979

  7. Effect of heat shock on the chilling sensitivity of trichomes and petioles of African violet (Saintpaulia ionantha).

    PubMed

    Saltveit, Mikal E.; Hepler, Peter K.

    2004-05-01

    Chilling at 6 degrees C caused an immediate cessation of protoplasmic streaming in trichomes from African violets (Saintpaulia ionantha), and a slower aggregation of chloroplasts in the cells. Streaming slowly recovered upon warming to 20 degrees C, reaching fairly stable rates after 4, 15, 25 and 35 min for tissue chilled for 2 min and for 2, 14 and 24 h, respectively. The rate of ion leakage from excised petioles into an isotonic 0.2 M mannitol solution increased after 12 h of chilling and reached a maximum after 3 days of chilling. A heat shock at 45 degrees C for 6 min reduced chilling-induced rates of ion leakage from excised 1-cm petiole segments by over 50%, namely to levels near that from non-chilled control tissue. Heat-shock treatments themselves had no effect on the rate of ion leakage from non-chilled petiole segments. Protoplasmic streaming was stopped by 1 min of heat shock at 45 degrees C, but slowly recovered to normal levels after about 30 min Chloroplasts aggregation was prevented by a 1 or 2 min 45 degrees C heat-shock treatment administered 1.5 h before chilling, but heat-shock treatments up to 6 min only slightly delayed the reduction in protoplasmic streaming caused by chilling. Tradescantia virginiana did not exhibit symptoms associated with chilling injury in sensitive species (i.e. cessation of protoplasmic streaming in stamen hairs and increased ion leakage from leaf tissue). PMID:15086815

  8. Androsterone-induced molecular and physiological changes in maize seedlings in response to chilling stress.

    PubMed

    Erdal, Serkan

    2012-08-01

    The aim of study was to elucidate the influence of foliar sprays of androsterone in alleviating detrimental effects of chilling stress in maize seedlings. Eleven-days-old maize seedlings were treated with 10(-9) mol L(-1) androsterone and then transferred to a chamber with temperature of 10/7 °C (day/night) for 3 days. The stress injury was measured in terms of increase in electrolyte leakage, superoxide production and hydrogen peroxide level, and decrease in chlorophyll content. Androsterone application mitigated significantly the chilling-induced stress injury. Under chilling stress, the oxidative damage which was measured as malondialdehyde content was lesser in androsterone-applied seedlings that were associated with greater activities of superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (POX), ascorbate peroxidase (APX) and glutathione reductase (GR). Moreover, SOD, POX and APX isozymes exhibited a strong correlation with changes in their activities. Androsterone application enhanced the level of antioxidant compounds like ascorbic acid, glutathione, proline and carotenoid as well as activities of antioxidant enzymes. Similarly, while androsterone treatment increased total antioxidant status, it reduced total oxidant status relative to chilling-stressed seedlings alone. Soluble protein profile was significantly changed by only chilling stress and chilling stress plus androsterone treatment, as well. According to these findings, it is possible to say that androsterone could be used to alleviate the damaging effects of chilling stress by improving antioxidative system in maize seedlings. This is the first study elucidating the effects of androsterone on resistance to chilling stress of plants. PMID:22634365

  9. Chill-coma recovery time, age and sex determine lipid profiles in Ceratitis capitata tissues.

    PubMed

    Pujol-Lereis, Luciana Mercedes; Fagali, Natalia Soledad; Rabossi, Alejandro; Catalá, Ángel; Quesada-Allué, Luis Alberto

    2016-04-01

    The remodeling of membrane composition by changes in phospholipid head groups and fatty acids (FA) degree of unsaturation has been associated with the maintenance of membrane homeostasis under stress conditions. Overall lipid levels and the composition of cuticle lipids also influence insect stress resistance and tissue protection. In a previous study, we demonstrated differences in survival, behavior and Cu/Zn superoxide dismutase gene expression between subgroups of Ceratitis capitata flies that had a reversible recovery from chill-coma and those that developed chilling-injury. Here, we analyzed lipid profiles from comparable subgroups of 15 and 30-day-old flies separated according to their recovery time after a chill-coma treatment. Neutral and polar lipid classes of chill-coma subgroups were separated by thin layer chromatography and quantified by densitometry. FA composition of polar lipids of chill-coma subgroups and non-stressed flies was evaluated using gas chromatography coupled to mass spectrometry. Higher amounts of neutral lipids such as triglycerides, diacylglycerol, wax esters, sterol esters and free esters were found in male flies that recovered faster from chill-coma compared to slower flies. A multivariate analysis revealed changes in patterns of storage and cuticle lipids among subgroups both in males and females. FA unsaturation increased after cold exposure, and was higher in thorax of slower subgroups compared to faster subgroups. The changes in neutral lipid patterns and FA composition depended on recovery time, sex, age and body-part, and were not specifically associated with the development of chilling-injury. An analysis of phospholipid classes showed that the phosphatidylcholine to lysophosphatidylcholine ratio (PC/LPC) was significantly higher, or showed a tendency, in subgroups that may have developed chilling-injury compared to those with a reversible recovery from coma. PMID:26868723

  10. Study on adsorption and desorption of ammonia on graphene.

    PubMed

    Zhang, Zhengwei; Zhang, Xinfang; Luo, Wei; Yang, Hang; He, Yanlan; Liu, Yixing; Zhang, Xueao; Peng, Gang

    2015-12-01

    The gas sensor based on pristine graphene with conductance type was studied theoretically and experimentally. The time response of conductance measurements showed a quickly and largely increased conductivity when the sensor was exposed to ammonia gas produced by a bubble system of ammonia water. However, the desorption process in vacuum took more than 1 h which indicated that there was a larger number of transferred carriers and a strong adsorption force between ammonia and graphene. The desorption time could be greatly shortened down to about 2 min by adding the flow of water-vapor-enriched air at the beginning of the recovery stage which had been confirmed as a rapid and high-efficiency desorption process. Moreover, the optimum geometries, adsorption energies, and the charge transfer number of the composite systems were studied with first-principle calculations. However, the theoretical results showed that the adsorption energy between NH3 and graphene was too small to fit for the experimental phenomenon, and there were few charges transferred between graphene and NH3 molecules, which was completely different from the experiment measurement. The adsorption energy between NH4 and graphene increased stage by stage which showed NH4 was a strong donor. The calculation suggested that H2O molecule could help a quick desorption of NH4 from graphene by converting NH4 to NH3 or (NH3)n(H2O)m groups, which was consistent with the experimental results. This study demonstrates that the ammonia gas produced by a bubble system of ammonia water is mainly ammonium groups of NH3 and NH4, and the NH4 moleculars are ideal candidates for the molecular doping of graphene while the interaction between graphene and the NH3 moleculars is weak. PMID:26377212

  11. Study on adsorption and desorption of ammonia on graphene

    NASA Astrophysics Data System (ADS)

    Zhang, Zhengwei; Zhang, Xinfang; Luo, Wei; Yang, Hang; He, Yanlan; Liu, Yixing; Zhang, Xueao; Peng, Gang

    2015-09-01

    The gas sensor based on pristine graphene with conductance type was studied theoretically and experimentally. The time response of conductance measurements showed a quickly and largely increased conductivity when the sensor was exposed to ammonia gas produced by a bubble system of ammonia water. However, the desorption process in vacuum took more than 1 h which indicated that there was a larger number of transferred carriers and a strong adsorption force between ammonia and graphene. The desorption time could be greatly shortened down to about 2 min by adding the flow of water-vapor-enriched air at the beginning of the recovery stage which had been confirmed as a rapid and high-efficiency desorption process. Moreover, the optimum geometries, adsorption energies, and the charge transfer number of the composite systems were studied with first-principle calculations. However, the theoretical results showed that the adsorption energy between NH3 and graphene was too small to fit for the experimental phenomenon, and there were few charges transferred between graphene and NH3 molecules, which was completely different from the experiment measurement. The adsorption energy between NH4 and graphene increased stage by stage which showed NH4 was a strong donor. The calculation suggested that H2O molecule could help a quick desorption of NH4 from graphene by converting NH4 to NH3 or (NH3)n(H2O)m groups, which was consistent with the experimental results. This study demonstrates that the ammonia gas produced by a bubble system of ammonia water is mainly ammonium groups of NH3 and NH4, and the NH4 moleculars are ideal candidates for the molecular doping of graphene while the interaction between graphene and the NH3 moleculars is weak.

  12. System Modeling for Ammonia Synthesis Energy Recovery System

    NASA Astrophysics Data System (ADS)

    Bran Anleu, Gabriela; Kavehpour, Pirouz; Lavine, Adrienne; Ammonia thermochemical Energy Storage Team

    2015-11-01

    An ammonia thermochemical energy storage system is an alternative solution to the state-of-the-art molten salt TES system for concentrating solar power. Some of the advantages of this emerging technology include its high energy density, no heat losses during the storage duration, and the possibility of long storage periods. Solar energy powers an endothermic reaction to disassociate ammonia into hydrogen and nitrogen, which can be stored for future use. The reverse reaction is carried out in the energy recovery process; a hydrogen-nitrogen mixture flowing through a catalyst bed undergoes the exothermic ammonia synthesis reaction. The goal is to use the ammonia synthesis reaction to heat supercritical steam to temperatures on the order of 650°C as required for a supercritical steam Rankine cycle. The steam will flow through channels in a combined reactor-heat exchanger. A numerical model has been developed to determine the optimal design to heat supercritical steam while maintaining a stable exothermic reaction. The model consists of a transient one dimensional concentric tube counter-flow reactor-heat exchanger. The numerical model determines the inlet mixture conditions needed to achieve various steam outlet conditions.

  13. Fabrication of a photocurable highly sensitive optical ammonia sensor for aquaculture application

    NASA Astrophysics Data System (ADS)

    Aziz, Aiman; Hafizah I., N.; Norzaliman M. Z., M.; Witjaksono, G.

    2014-05-01

    A simple sensor fabrication process for ammonia fluorescence based optical sensing has been developed by immobilizing fluorescence pair dyes in a UV-photocurable acrylate host polymer matrix. The direct process for optical sensor was designed by entrapping ammonia sensitive components in a certain ratio of acrylate monomers of methyl methacrylate (MMA) and butyl acrylate (BA). The copolymers poly(methyl metha-co-butyl acrylate) (MB) glassy transparent thin film ammonia sensor was photopolymerized under ultra-violet (UV) illumination. The acrylate based host matrix offers rapid curing, ease of preparation, excellent dyes entrapment and self-adhesive properties. The nonplasticized acrylate matrix containing ammonia sensitive components have demonstrated excellent sensitivity towards target analyte with linear sensor response to dissolved ammonia in the range of 1 to 100 μgL-1 (R2 of 0.9) with a limit detection of 1 μgL-1ammonia. The simple single step fabrication of ammonia fluorescence based optical sensor offers great manufacturing capability for aquaculture quality monitoring.

  14. Decreasing ammonia inhibition in thermophilic methanogenic bioreactors using carbon fiber textiles.

    PubMed

    Sasaki, Kengo; Morita, Masahiko; Hirano, Shin-ichi; Ohmura, Naoya; Igarashi, Yasuo

    2011-05-01

    Ammonia accumulation is one of the main causes of the loss of methane production observed during fermentation. We investigated the effect of addition of carbon fiber textiles (CFT) to thermophilic methanogenic bioreactors with respect to ammonia tolerance during the process of degradation of artificial garbage slurry, by comparing the performance of the reactors containing CFT with the performance of reactors without CFT. Under total ammonia-N concentrations of 3,000 mg L(-1), the reactors containing CFT were found to mediate stable removal of organic compounds and methane production. Under these conditions, high levels of methanogenic archaea were retained at the CFT, as determined by 16S rRNA gene analysis for methanogenic archaea. In addition, Methanobacterium sp. was found to be dominant in the suspended fraction, and Methanosarcina sp. was dominant in the retained fraction of the reactors with CFT. However, the reactors without CFT had lower rates of removal of organic compounds and production of methane under total ammonia-N concentrations of 1,500 mg L(-1). Under this ammonia concentration, a significant accumulation of acetate was observed in the reactors without CFT (130.0 mM), relative to the reactors with CFT (4.2 mM). Only Methanobacterium sp. was identified in the reactors without CFT. These results suggest that CFT enables stable proliferation of aceticlastic methanogens by preventing ammonia inhibition. This improves the process of stable garbage degradation and production of methane in thermophilic bioreactors that include high levels of ammonia. PMID:21468711

  15. Chilling temperature stimulates growth, gene over-expression and podophyllotoxin biosynthesis in Podophyllum hexandrum Royle.

    PubMed

    Yang, De Long; Sun, Ping; Li, Meng Fei

    2016-10-01

    Podophyllotoxin (PPT) and its derivatives, isolated from the rhizome of Podophyllum hexandrum Royle (P. hexandrum), are typically used in clinical settings for anti-cancer and anti-virus treatments. Empirical studies have verified that P. hexandrum had stronger tolerance to chilling, due to involving PPT accumulation in rhizome induced by cold stress. However, the cold-adaptive mechanism and its association with PPT accumulation at a molecular level in P. hexandrum are still limited. In this study, the morpho-physiological traits related to plant growth, PPT accumulation and key gene expressions controlling PPT biosynthesis were assessed by exposing P. hexandrum seedlings to different temperatures (4 °C and 10 °C as chilling stress and 22 °C as the control). The results showed that chilling significantly increased chlorophyll content, net photosynthetic rate, stomatal conductance, and plant biomass, whereas it greatly decreased transpiration rates and intercellular CO2 concentration. Compared to the control, the chilling treatments under 4 °C and 10 °C conditions induced a 5.00- and 3.33-fold increase in PPT contents, respectively. The mRNA expressions of six key genes were also up-regulated by chilling stresses. The findings are useful in understanding the molecular basis of P. hexandrum response to chilling. PMID:27314513

  16. Effects of exogenous nitric oxide in wheat seedlings under chilling stress.

    PubMed

    Esim, Nevzat; Atici, Okkes; Mutlu, Salih

    2014-04-01

    The effects of nitric oxide (NO) on chilling tolerance (contents of hydrogen peroxide (H2O2) and superoxide anion (O2 (-)) and lipid peroxidation level (malondialdehyde, MDA)) and the activities of antioxidant enzymes (superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT)) were investigated in the leaves of wheat (Triticum aestivum L.) exposed to chilling. NO treatment was carried out through spraying of sodium nitroprusside (SNP), which is a donor of NO. To do this, SNP concentrations of 0.1 and 1 mM were applied on the leaves of 11-day plants and the plants were then exposed to chilling conditions (5/2°C) for 3 days. The chilling stress treatment increased both the activities of antioxidant enzymes and the levels of MDA, H2O2 and O2 (-). Similarly, NO treatment enhanced SOD, POX and CAT activities under chilling stress, whereas it decreased H2O2 and O2 (.) (-) contents as well as MDA level. The most effective concentration was determined as 0.1 mM SNP. Exogenous SNP application as a donor of NO was found to have an important ameliorative effect on cold tolerance of seedling exposed to chilling stress by stimulating antioxidant enzyme activity. PMID:22903172

  17. Preparation and characterization of microparticles of piroxicam by spray drying and spray chilling methods

    PubMed Central

    Dixit, M.; Kini, A.G.; Kulkarni, P.K.

    2010-01-01

    Piroxicam, an anti-inflammatory drug, exhibits poor water solubility and flow properties, poor dissolution and poor wetting. Consequently, the aim of this study was to improve the dissolution of piroxicam. Microparticles containing piroxicam were produced by spray drying, using isopropyl alcohol and water in the ratio of 40:60 v/v as solvent system, and spray chilling technology by melting the drug and chilling it with a pneumatic nozzle to enhance dissolution rate. The prepared formulations were evaluated for in vitro dissolution and solubility. The prepared drug particles were characterized by scanning electron microscopy (SEM), differential scanning calorimeter, X-ray diffraction and Fourier transform infrared spectroscopy. Dissolution profile of the spray dried microparticles was compared with spray-chilled microparticles, pure and recrystallized samples. Spray dried microparticles and spray chilled microparticles exhibited decreased crystallinity and improved micromeritic properties. The dissolution of the spray dried microparticle and spray chilled particles were improved compared with recrystallized and pure sample of piroxicam. Consequently, it was believed that spray drying of piroxicam is a useful tool to improve dissolution but not in case of spray chilling. This may be due to the degradation of drug or variations in the resonance structure or could be due to minor distortion of bond angles. Hence, this spray drying technique can be used for formulation of tablets of piroxicam by direct compression with directly compressible tablet excipients. PMID:21589797

  18. Effect of spray-chilling on quality of beef from lean and fatter carcasses.

    PubMed

    Hippe, C L; Field, R A; Ray, B; Russell, W C

    1991-01-01

    Carcasses from five trim cows and five choice steers were used to study the effects of spray-chilling on cooler shrink, chill rate, purge loss from vacuum-packaged cuts, cook loss, shear values and bacterial growth. Spray-chilling reduced cooler shrink but had no effect on chill rate, purge loss from vacuum-packaged cuts, cook loss or shear values. Aerobes, facultative anaerobes, aerobic psychrotrophs, facultative anaerobic psychrotrophs and lactic acid bacteria all tended to be higher on rounds from spray-chilled sides. Leaner (and lighter) cow carcasses chilled faster and had lost a higher percentage of their weight at 24 h than fatter and heavier steer carcasses. The leaner carcasses had higher bacterial counts initially and throughout storage. This difference may have been due to differences in the level of initial contamination during dressing and not due to the carcasses' leanness. Purge-weight loss for each carcass increased and cooking weight loss decreased with increased storage times, making the total weight loss from meat aged 5 vs 10 wk similar. PMID:2005011

  19. Metabolism and energy supply below the critical thermal minimum of a chill-susceptible insect.

    PubMed

    Macmillan, Heath A; Williams, Caroline M; Staples, James F; Sinclair, Brent J

    2012-04-15

    When exposed to temperatures below their critical thermal minimum (CT(min)), insects enter chill-coma and accumulate chilling injuries. While the critical thermal limits of water-breathing marine animals may be caused by oxygen- and capacity-limitation of thermal tolerance (OCLT), the mechanisms are poorly understood in air-breathing terrestrial insects. We used thermolimit respirometry to characterize entry into chill-coma in a laboratory population of fall field crickets (Gryllus pennsylvanicus). To detect potential oxygen limitation, we quantified muscle ATP, lactate and alanine concentrations in crickets following prolonged exposure to 0°C (a temperature that causes chill-coma, chilling injury and eventual death). Although there was a sharp (44%) drop in the rate of CO(2) emission at the CT(min) and spiracular control was lost, there was a low, continuous rate of CO(2) release throughout chill-coma, indicating that the spiracles were open and gas exchange could occur through the tracheal system. Prolonged exposure to 0°C caused muscle ATP levels to increase marginally (rather than decrease as OCLT would predict), and there was no change in muscle lactate or alanine concentration. Thus, it appears that insects are not susceptible to OCLT at low temperatures but that the CT(min) may instead be set by temperature effects on whole-animal ion homeostasis. PMID:22442375

  20. Ammonia oxidizing bacteria and archaea in horizontal flow biofilm reactors treating ammonia-contaminated air at 10 °C.

    PubMed

    Gerrity, Seán; Clifford, Eoghan; Kennelly, Colm; Collins, Gavin

    2016-05-01

    The objective of this study was to demonstrate the feasibility of novel, Horizontal Flow Biofilm Reactor (HFBR) technology for the treatment of ammonia (NH3)-contaminated airstreams. Three laboratory-scale HFBRs were used for remediation of an NH3-containing airstream at 10 °C during a 90-d trial to test the efficacy of low-temperature treatment. Average ammonia removal efficiencies of 99.7 % were achieved at maximum loading rates of 4.8 g NH3 m(3) h(-1). Biological nitrification of ammonia to nitrite (NO2 (-)) and nitrate (NO3 (-)) was mediated by nitrifying bacterial and archaeal biofilm populations. Ammonia-oxidising bacteria (AOB) were significantly more abundant than ammonia-oxidising archaea (AOA) vertically at each of seven sampling zones along the vertical HFBRs. Nitrosomonas and Nitrosospira, were the two most dominant bacterial genera detected in the HFBRs, while an uncultured archaeal clone dominated the AOA community. The bacterial community composition across the three HFBRs was highly conserved, although variations occurred between HFBR zones and were driven by physicochemical variables. The study demonstrates the feasibility of HFBRs for the treatment of ammonia-contaminated airstreams at low temperatures; identifies key nitrifying microorganisms driving the removal process; and provides insights for process optimisation and control. The findings are significant for industrial applications of gas oxidation technology in temperate climates. PMID:26879980