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Sample records for chilled ammonia process

  1. Chilled Ammonia Process for CO2 Capture

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; Thomsen, Kaj; Well, Willy J.M. van;

    2010-01-01

    The chilled ammonia process absorbs the CO2 at low temperature (2–10°C). The heat of absorption of carbon dioxide by ammonia is significantly lower than for amines. In addition, degradation problems can be avoided and a high carbon dioxide capacity is achieved. Hence, this process shows good...... and pressure up to 100bars. The results show that solid phases consisting of ammonium carbonate and bicarbonate are formed in the absorber. The heat requirements in the absorber and in the desorber have been studied. The enthalpy calculations show that a heat requirement for the desorber lower than 2GJ/ton CO2...

  2. Chilled ammonia process for CO2 capture

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; Thomsen, Kaj; van Well, Willy J. M;

    2009-01-01

    The chilled ammonia process absorbs the CO2 at low temperature (2-10 degrees C). The heat of absorption of carbon dioxide by ammonia is significantly lower than for amines. In addition, degradation problems can be avoided and a high carbon dioxide capacity is achieved. Hence, this process shows...... C and pressure up to 100 bars [1]. The results show that solid phases consisting of ammonium carbonate and bicarbonate are formed in the absorber. The energy requirements in the absorber and in the desorber have been studied. The enthalpy calculations show that an energy requirement for the desorber...

  3. Alternative Layouts for the Carbon Capture with the Chilled Ammonia Process

    DEFF Research Database (Denmark)

    Valenti, Gianluca; Bonalumi, Davide; Fosbøl, Philip Loldrup;

    2013-01-01

    Many alternatives are being investigated for the carbon capture, but none appears to have been proved as the choice for full-scale applications. This work considers the Chilled Ammonia Process for coal-fired Ultra Super Critical power plants. Three layouts are simulated with Aspen Plus and the Ex......Many alternatives are being investigated for the carbon capture, but none appears to have been proved as the choice for full-scale applications. This work considers the Chilled Ammonia Process for coal-fired Ultra Super Critical power plants. Three layouts are simulated with Aspen Plus...

  4. Alternative Layouts for the Carbon Capture with the Chilled Ammonia Process

    OpenAIRE

    Valenti, Gianluca; Bonalumi, Davide; Fosbøl, Philip Loldrup; Macchi, Ennio; Thomsen, Kaj; Gatti, Dominicc

    2013-01-01

    Many alternatives are being investigated for the carbon capture, but none appears to have been proved as the choice for full-scale applications. This work considers the Chilled Ammonia Process for coal-fired Ultra Super Critical power plants. Three layouts are simulated with Aspen Plus and the Extended UNIQUAC thermodynamic model. Compared to a traditional layout, stripping of the wash water of the absorber or, better, splitting the rich solution between the middle and the top of the column l...

  5. Chills

    Science.gov (United States)

    Chills refers to feeling cold after being in a cold environment. The word can also refer to ... Chills (shivering) may occur at the beginning of an infection. They are most often associated with a ...

  6. SOME ASPECTS OF TECHNOLOGICAL PROCESS OF CASTINGS IN COATED CHILL

    Directory of Open Access Journals (Sweden)

    A. N. Krutilin

    2010-01-01

    Full Text Available Analysis of technological process of pouring into coated iron chill is presented. It is shown that the process is very sensitive to the change of technological parameters, is rather complex in regulation and control.

  7. Chill Down Process of Hydrogen Transport Pipelines

    Science.gov (United States)

    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.

  8. Effects of chill casting processes on secondary dendrite arm spacing and densification of Al-Si-Mg alloy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on the resin bonded sand casting process, the effects of chill processes on the secondary dendrite arm spacing(SDAS) and densification of Al-Si-Mg alloy were studied. The influences of the chill thickness and effective distance of chill operating on the SDAS were researched; and the effect of chillheat capacity on SDAS was investigated. The result reveals that,SDAS decreases with increasing the thickness of chill but the effect of chill is finite. The effective distance of chill operating for the chill with different thickness were obtained, and the functional relations among modulus, length of castings and thickness of chill were discussed, and the synthetical network chart of the relation among them was plotted. The relationship between local solidification rate and SDAS was defined by means of quadratic polynomial regression.

  9. Quality and safety of fish curry processed by sous vide cook chilled and hot filled technology process during refrigerated storage.

    Science.gov (United States)

    Shakila, R Jeya; Raj, B Edwin; Felix, N

    2012-06-01

    Fish curry, a traditional Indian dish was prepared from farmed fish Cobia (Rachycentron canadum), packaged by two different cook-chill processes namely, sous vide cook chilled and hot filled technology and held at 2 °C. Biochemical composition revealed that fish curry contained 5% protein and 6% fat. Omega-3 fatty acids, eicosapentaenoic acid (EPA) retained 55.44% while docosahexaenoic acid (DHA) retained 29% during cook-chilling process. The major fatty acids in fish curry were C18:2, C12:0, C16:0 and C18:1. Shelf-life of sous vide cook chilled and hot filled technology processed fish curry were 8 and 12 weeks, respectively. Total bacterial counts were detected after 4 weeks and 12 weeks in sous vide cook chilled and hot filled technology processes, respectively. Total staphylococci were detected in sous vide cook chilled and hot filled technology processed cobia fish curry after 4 and 12 weeks, respectively. Total bacilli, anaerobic sulfite reducing clostridia, Salmonella, and lactic acid bacteria were absent. Hot filled technology process was more efficient and could be applied for chilled fish curry preservation for 12 weeks without any safety problems.

  10. Quality and safety of fish curry processed by sous vide cook chilled and hot filled technology process during refrigerated storage.

    Science.gov (United States)

    Shakila, R Jeya; Raj, B Edwin; Felix, N

    2012-06-01

    Fish curry, a traditional Indian dish was prepared from farmed fish Cobia (Rachycentron canadum), packaged by two different cook-chill processes namely, sous vide cook chilled and hot filled technology and held at 2 °C. Biochemical composition revealed that fish curry contained 5% protein and 6% fat. Omega-3 fatty acids, eicosapentaenoic acid (EPA) retained 55.44% while docosahexaenoic acid (DHA) retained 29% during cook-chilling process. The major fatty acids in fish curry were C18:2, C12:0, C16:0 and C18:1. Shelf-life of sous vide cook chilled and hot filled technology processed fish curry were 8 and 12 weeks, respectively. Total bacterial counts were detected after 4 weeks and 12 weeks in sous vide cook chilled and hot filled technology processes, respectively. Total staphylococci were detected in sous vide cook chilled and hot filled technology processed cobia fish curry after 4 and 12 weeks, respectively. Total bacilli, anaerobic sulfite reducing clostridia, Salmonella, and lactic acid bacteria were absent. Hot filled technology process was more efficient and could be applied for chilled fish curry preservation for 12 weeks without any safety problems. PMID:22701059

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  13. Ammonia Process by Pressure Swing Adsorption

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Optimization of biomethanation focusing on high ammonia loaded processes

    DEFF Research Database (Denmark)

    Wang, Han

    , could theoretically mitigate the ammonia inhibition problem (Angelidaki et al., 1999). Therefore, the effect of co-digestion of cattle manure with lipids (i.e. glycerol trioleate (GTO)) under high ammonia levels (5 g NH4+-N·L-1) in anaerobic continuous stirred tank (CSTR) reactors (RGTO) was assessed......” was observed, which caused a deterioration of the inhibition effect in anaerobic digestion process. On contrary, the reactor where glucose was co-digested demonstrated higher tolerance to ammonia toxicity compared with the reactor where GTO was used. Secondly, the problem of ammonia inhibition during...... in continuous reactors. Furthermore, bioaugmentation with an ammonia tolerant methanogen to alleviate ammonia toxicity could be applied for improving the efficiency of biomethanation process in full-scale continuous reactors. Finally, an innovative method, where hydrogen is injected in the anaerobic reactor...

  15. Experimental investigation on chill-down process of cryogenic flow line

    Science.gov (United States)

    Jin, Lingxue; Park, Changgi; Cho, Hyokjin; Lee, Cheonkyu; Jeong, Sangkwon

    2016-10-01

    This paper describes the cryogenic chill-down experiments that are conducted on a 12.7 mm outer diameter, 1.25 mm wall thickness and 7 m long stainless steel horizontal pipe with liquid nitrogen (LN2). The pipe is vacuum insulated during the experiment to minimize the heat leak from room temperature and to enable one to numerically simulate the process easily. The temperature and the pressure profiles of the chill-down line are obtained at the location which is 5.5 m in a distance from the pipe inlet. The mass flux range is approximately from 19 kg/m2 s to 49 kg/m2 s, which corresponds to the Reynolds numbers range from 1469 to 5240. The transient histories of temperature, pressure and mass flow rate during the line chill-down process are monitored, and the heat transfer coefficient and the heat flux are computed by an inverse problem solving method. The amplitude of the pressure oscillation and the oscillating period become larger and longer at higher pressure conditions. In the low mass flux conditions, the critical heat flux in horizontal pipes is not sensitive to mass flux, and is higher than that in vertical pipes. Kutateladze's correlation with the constant coefficient, B = 0.029 , well matches the experimental data in the current work. In nucleate flow boiling regime, heat transfer coefficient, h , is proportional to (q″)n , and n is equal to 0.7.

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

    Science.gov (United States)

    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 ...

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

    Science.gov (United States)

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

  18. A Study of Life-type Processes in Liquid Ammonia

    OpenAIRE

    Griffin, Joseph

    2015-01-01

    Liquid ammonia (LNH3) has a number of properties similar to water, such as the ability to dissolve a diverse range of chemical compounds and, based on the variety of chemical reactions in this non-aqueous solvent, speculation has arisen about the possibility of life processes in liquid ammonia. "Life" is difficult to define, but the general consensus is that it is comprised of a variety of individual process that could be regarded as "processes of life", some of which can be modelled withi...

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

    Science.gov (United States)

    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.

  20. The chilling of carcasses.

    Science.gov (United States)

    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).

  1. Evaluating the impact of an ammonia-based post-combustion CO2 capture process on a steam power plant with different cooling water temperatures

    DEFF Research Database (Denmark)

    Linnenberg, Sebastian; Darde, Victor Camille Alfred; Oexmann, Jochen;

    2012-01-01

    pressure, solvent circulation rate, solvent recycling rate and chilling temperature) are evaluated and the optimal configuration with respect to the overall net efficiency penalty is determined.The study shows that the configuration of the process with absorption at low temperature (approximately 10°C......) with or without precipitation of ammonium carbonate compounds leads to a lower net efficiency penalty than an MEA-based process, assuming that low temperature cooling water is available. An estimate of the size of the absorber shows that the absorber columns of an ammonia-based process are significantly higher...

  2. A comparative kinetic study of SNCR process using ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Javed, M. Tayyeb; Ahmed, Z.; Ibrahim, M. Asim; Irfan, N.

    2008-07-01

    The paper presents comparative kinetic modelling of nitrogen oxides (NOx) removal from flue gases by selective non-catalytic reduction process using ammonia as reducing agent. The computer code SENKIN is used in this study with the three published chemical kinetic mechanisms; Zanoelo, Kilpinen and Skreiberg. Kinetic modeling was performed for an isothermal plug flow reactor at atmospheric pressure so as to compare it with the experimental results. A 500 ppm NOx background in the flue gas is considered and kept constant throughout the investigation. The ammonia performance was modeled in the range of 750 to 1250{sup o}C using the molar ratios NH{sub 3}/NOx from 0.25 to 3.0 and residence times up to 1.5 seconds. The modeling using all the mechanisms exhibits and confirms a temperature window of NOx reduction with ammonia. It was observed that 80% of NOx reduction efficiency could be achieved if the flue gas is given 300 msec to react with ammonia, while it is passing through a section within a temperature range of 910 to 1060{sup o}C (Kilpinen mechanism) or within a temperature range of 925 to 1030{sup o}C (Zanoelo mechanism) or within a temperature range of 890 to 1090{sup o}C (Skreiberg mechanism). 20 refs., 6 figs.

  3. Application of Silicon Carbide Chills in Controlling the Solidification Process of Casts Made of IN-713C Nickel Superalloy

    Directory of Open Access Journals (Sweden)

    D. Szeliga

    2012-12-01

    Full Text Available The paper presents the method of manufacturing casts made of the IN-713C nickel superalloy using the wax lost investment castingprocess and silicon carbide chills. The authors designed experimental casts, the gating system and selected the chills material. Wax pattern,ceramic shell mould and experimental casts were prepared for the purposes of research. On the basis of the temperature distributionmeasurements, the kinetics of the solidification process was determined in the thickened part of the plate cast. This allowed to establish thequantity of phase transitions which occurred during cast cooling process and the approximate values of liquidus, eutectic, solidus andsolvus temperatures as well as the solidification time and the average value of cast cooling rate. Non-destructive testing and macroscopicanalysis were applied to determine the location and size of shrinkage defects. The authors present the mechanism of solidification andformation of shrinkage defects in casts with and without chills. It was found that the applied chills influence significantly the hot spots andthe remaining part of the cast. Their presence allows to create conditions for solidification of IN-713C nickel superalloy cast withoutshrinkage defects.

  4. Process for nondestructively testing with radioactive gas using a chill set sealant

    International Nuclear Information System (INIS)

    An article surface is nondestructively tested for substantially invisible surface voids by absorbing a radioactive gas thereon. The adsorbed radioactive gas is disproportionately retained on those surfaces presented by the substantially invisible surface voids as compared to the remaining surfaces of the article contacted by the radioactive gas. The radiation released by the radioactive gas remaining adsorbed is used to identify the substantially invisible voids. To immobilize the radioactive gas adjacent or within the surface voids, a sealant composition is provided which is capable of being chill set. The temperatures of the article surface to be tested and the sealant composition are then related so that the article surface is at a temperature below the chill set temperature of the sealant composition and the sealant composition is at a temperature above its chill set temperature. The article portion to be tested is then coated with sealant composition to form a chill set coating thereon of substantially uniform thickness. (U.S.)

  5. Chilling Tendency and Chill of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    E. Fra(s); M. Górny; W. Kapturkiewicz; H. López

    2008-01-01

    An analytical expression is presented for the susceptibility of liquid cast iron to solidify according tothe Fe-C-X metastable system (also known as the chilling tendency of cast iron, CT). The analysis incorpo-rates the nucleation and growth processes associated with the eutectic transformation. The CT is related tothe physicochemical state of the liquid, the eutectic cells in the flake graphite, and the number of nodules innodular cast iron. In particular, the CT can be related to the critical wall thickness, Scr, or the chill width, Wcr,in wedge shaped castings. Finally, this work serves as a guide for understanding the effect of technical fac-tors such as the melt chemistry, the spheroidizing and inoculation practice, and the holding time and tam-perature on the resultant CT and chill of the cast iron. Theoretical calculations of Scr and Wcr compare wellwith experimental data for flake graphite and nodular cast iron.

  6. Aqueous ammonia process for CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Darde, V.; Thomsen, K.; Stenby, E.H. (Technical Univ. of Denmark, Dept. of Chemical and Biochemical Engineering, Kgs. Lyngby (Denmark)); Well, W.J.M. van (DONG Energy Power, Chemical and Materials Dept (Denmark))

    2009-09-15

    This work deals with the study of a post combustion carbon dioxide capture process using aqueous solutions of ammonia as solvent. Amine solutions have been commonly used for the commercial production of CO{sub 2}. The main disadvantage related to the use of amine solutions is the high energy consumption (3.5 - 4 GJ/ton CO{sub 2}) and the high degradation rate of the amines. The heat of absorption of carbon dioxide by ammonia is significantly lower than for alkanolamines. Hence, this process shows good perspectives. However, a scientific understanding of the processes is required. In order to simulate and optimize the process, a thermodynamic model for the system is required. The properties of the NH{sub 3}-CO{sub 2}-H{sub 2}O system were previously modeled using the Extended UNIQUAC electrolyte model in the temperature range from 0 to 110 deg. C, the pressure range from 0 to 100 bars and for a molality of ammonia up to approximately 80. In this work, the validity of this model was extended up to 150 deg. C. Also additional data for the enthalpy of partial evaporation and speciation data were used. The equilibrium composition and enthalpy of the different streams of the process have been studied, based on the information from a patent. The results show that solid phases consisting of ammonium carbonate compounds are formed in the absorber. It also shows that the pure CO{sub 2} stream that leaves the stripper is pressurized. The energy requirements in the absorber and in the desorber have been studied. An energy consumption in the desorber lower than 2 GJ/ton CO{sub 2} can be reached. (au)

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

    Science.gov (United States)

    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.

  8. Detection of Ammonia-Oxidizing Archaea in Fish Processing Effluent Treatment Plants

    OpenAIRE

    Devivaraprasad Reddy, A.; Subrahmanyam, Gangavarapu; Shivani Kallappa, Girisha; Karunasagar, Iddya; Karunasagar, Indrani

    2014-01-01

    Ammonia oxidation is the rate limiting step in nitrification and thus have an important role in removal of ammonia in natural and engineered systems with participation of both ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB). However, their relative distribution and activity in fish processing effluent treatment plants (FPETPs) though significant, is hitherto unreported. Presence of AOA in sludge samples obtained from FPETPs was studied by amplification and sequencing of t...

  9. Process for the preparation of ammonia and heavy water

    International Nuclear Information System (INIS)

    A process for the production of ammonia and heavy water comprises the steps of enriching a flow of water with deuterium in a monothermal isotropic process; supplying a first portion of the deuterium-enriched water to a heavy water preparation plant to produce heavy water and hydrogen; storing a second portion of the deuterium-enriched water substantially without interruption during the colder half of a year; electrolytically dissociating the stored deuterium-enriched water substantially without interruption during the wamer half of a year to form hydrogen; storing a portion of the electrolytically-produced hydrogen during said warmer half of a year while supplying the remainder to a synthesis circuit of a synthesizing plant and subsequently supplying the stored hydrogen to the synthesis circuit during said colder half of a year; removing some of the synthesis gas mixture from the synthesis circuit of the synthesizing plant; burning the removed synthesis gas mixture with air to produce a mixture consisting mainly of water and nitrogen; thereafter condensing and separating the water from the mixture of water and nitrogen; supplying the nitrogen of the mixture of water and nitrogen, the hydrogen from the heavy water preparation plant and the electrolytically-produced hydrogen to the synthesis circuit of the synthesizing plant to produce ammonia; and collecting deuterium-depleted water resulting from said burning step and feeding the collected deuterium-depleted water into the monothermal process

  10. Sustainable Ammonia Synthesis – Exploring the scientific challenges associated with discovering alternative, sustainable processes for ammonia production

    Energy Technology Data Exchange (ETDEWEB)

    Nørskov, Jens [Stanford Univ., CA (United States); ; SLAC National Accelerator Lab., Menlo Park, CA (United States); Chen, Jingguang [Columbia Univ., New York, NY (United States); Brookhaven National Lab. (BNL), Upton, NY (United States); Miranda, Raul [Dept. of Energy (DOE), Washington DC (United States). Office of Science; Fitzsimmons, Tim [Dept. of Energy (DOE), Washington DC (United States). Office of Science; Stack, Robert [Dept. of Energy (DOE), Washington DC (United States). Office of Science

    2016-02-18

    Ammonia (NH3) is essential to all life on our planet. Until about 100 years ago, NH3 produced by reduction of dinitrogen (N2) in air came almost exclusively from bacteria containing the enzyme nitrogenase.. DOE convened a roundtable of experts on February 18, 2016. Participants in the Roundtable discussions concluded that the scientific basis for sustainable processes for ammonia synthesis is currently lacking, and it needs to be enhanced substantially before it can form the foundation for alternative processes. The Roundtable Panel identified an overarching grand challenge and several additional scientific grand challenges and research opportunities: -Discovery of active, selective, scalable, long-lived catalysts for sustainable ammonia synthesis. -Development of relatively low pressure (<10 atm) and relatively low temperature (<200 C) thermal processes. -Integration of knowledge from nature (enzyme catalysis), molecular/homogeneous and heterogeneous catalysis. -Development of electrochemical and photochemical routes for N2 reduction based on proton and electron transfer -Development of biochemical routes to N2 reduction -Development of chemical looping (solar thermochemical) approaches -Identification of descriptors of catalytic activity using a combination of theory and experiments -Characterization of surface adsorbates and catalyst structures (chemical, physical and electronic) under conditions relevant to ammonia synthesis.

  11. STUDY OF CYLPEBS CHILLING

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2016-01-01

    Full Text Available Methods of increasing the shock resistance of cast-iron grinding bodies are researched. The models of heat transfer in the process of casting and shock-abrasive wear are presented. Tooling to produce experimental samples of milling bodies chilling(gravity die casting is manufactured, samples of cylpebs are produced.

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

    Science.gov (United States)

    Autrey, S Thomas [West Richland, WA; Heldebrant, David J [Richland, WA; Linehan, John C [Richland, WA; Karkamkar, Abhijeet J [Richland, WA; Zheng, Feng [Richland, WA

    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.

  13. ThermoEnergy Ammonia Recovery Process for Municipal and Agricultural Wastes

    Directory of Open Access Journals (Sweden)

    Alex G. Fassbender

    2001-01-01

    Full Text Available The Ammonia Recovery Process (ARP is an award-winning, low-cost, environmentally responsible method of recovering nitrogen, in the form of ammonia, from various dilute waste streams and converting it into concentrated ammonium sulfate. The ThermoEnergy Biogas System utilizes the new chemisorption-based ARP to recover ammonia from anaerobically digested wastes. The process provides for optimal biogas production and significantly reduced nitrogen levels in the treated water discharge. Process flows for the ammonia recovery and ThermoEnergy biogas processes are presented and discussed. A comparison with other techniques such as biological nitrogen removal is made. The ARP technology uses reversible chemisorption and double salt crystal precipitation to recover and concentrate the ammonia. The ARP technology was successfully proven in a recent large-scale field demonstration at New York City’s Oakwood Beach Wastewater Treatment Plant, located on Staten Island. This project was a joint effort with Foster Wheeler Environmental Corporation, the Civil Engineering Research Foundation, and New York City Department of Environmental Protection. Independent validated plant data show that ARP consistently recovers up to 99.9% of the ammonia from the city’s centrate waste stream (derived from dewatering of sewage sludge, as ammonium sulfate. ARP technology can reduce the nitrogen (ammonia discharged daily into local bodies of water by municipalities, concentrated animal farming operations, and industry. Recent advances to ARP enhance its performance and economic competitiveness in comparison to stripping or ammonia destruction technologies.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  16. Effects of high-pressure processing on Listeria monocytogenes , spoilage microflora and multiple compound quality indices in chilled cold-smoked salmon

    DEFF Research Database (Denmark)

    Lakshmanan, R.; Dalgaard, Paw

    2004-01-01

    Aims: To evaluate the effect of high-pressure processing (HPP) on Listeria monocytogenes, microbial and chemical changes and shelf-life in chilled cold-smoked salmon (CSS).Methods and Results: First, challenge tests with L. monocytogenes were carried out using HPP of the product at 0.1 (control),...

  17. Nitrogen removal from sludge dewatering effluent through anaerobic ammonia oxidation process

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shao-hui; ZHENG Ping; HUA Yu-mei

    2005-01-01

    Anaerobic ammonia oxidation(Anammox) process is a novel and promising wastewater nitrogen removal process. The feasibility of transition of Anammox from denitrification and the performance of lab-scale Anammox biofilm reactor were investigated with sludge dewatering effluent. The results showed that Anammox process could be successfully started up after cultivation of denitrification biofilm and using it as inoculum. The transition of Anammox from denitrification was accomplished within 85 d. Anammox process was found suitable to remove ammonia from sludge dewatering effluent. The effluent ammonia concentration was detected to be 23.11 mgN/L at HRT of 28 h when influent ammonia concentration was fed 245 mgN/L, which was less than that for the national discharge standard Ⅱ (25 mgN/L) of 243.25 mg NH4+ -N/L and 288.31 mg NO2- -N/L.

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

    Science.gov (United States)

    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

  19. Study of the acceleration of ammonia generation process from poultry residues aiming at hydrogen production

    International Nuclear Information System (INIS)

    The hydrogen, utilized in fuel cells, can be produced from a variety of intermediate chemicals, between them, the ammonia. The ammonia gas as a raw material for the hydrogen production has been used due to its high energetic content, facility of decomposition, high availability, low prices, low storage pressure and its by-products are environmentally correct. One of the sources of ammonia is poultry and egg production systems. In these systems the ammonia is produced from the decomposition of uric acid present in the excreta of birds. The residue from the poultry-rearing farms is the broiler litter and from the egg production system is the excreta without any substrate. The characterization of these residues was performed using the Wavelength-Dispersive X-Ray Fluorescence (WDXRF), Elementary Analysis (CHN), Thermogravimetry and GC/MS - Gas chromatography/ Mass spectrometry. The studied factors which influence the ammonia volatilization were: nitrogen content, raising period, urease enzyme, temperature, pH and moisture content. The experiment results with poultry litter and excreta allow to conclude that the manipulation of the following parameters increased the ammonia emission: pH, nitrogen content, raising period, age of birds and excreta accumulation, urease enzyme and the temperature. The addition of different amounts of sand in the excreta and different volumes of water in the poultry litter inhibited the emission of ammonia. The variation of the quantity of material (broiler litter or excreta) and the volume of the flask used as incubator chamber showed no significant alterations to be chosen as a variable. The excreta was considered more appropriate than poultry litter for the objectives of this work due to the higher ammonia concentrations determined in this material. Due to the large amount of poultry litter and excreta from the production processes, the reuse of poultry residues to obtain ammonia is necessary to improve the quality of the local

  20. Microstructure and mechanical properties of NZ30K alloy by semi-continuous direct chill and sand mould casting processes

    Directory of Open Access Journals (Sweden)

    Zheng Xingwei

    2011-02-01

    Full Text Available The Mg-3.0Nd-0.2Zn-0.4Zr (NZ30K alloys were prepared by direct-chill casting (DCC and sand mould casting (SMC processes, respectively and their microstructures and mechanical properties were investigated. The results indicate that casting method plays a remarkable influence on the microstructure and mechanical properties of as-cast NZ30K alloy. The grain size increases from 35-40 μm in the billets made by the DCC to about 100-120 μm in the billets by the SMC. The aggregation of Mg12Nd usually found at the triple joints of grain boundaries in the billets prepared by SMC while is not observable from the billets by DCC. The tensile strengths and elongations of the billets are 195.2 MPa and 15.5% by DCC, and 162.5 MPa and 3.2% by SMC, respectively. The tensile strength of the alloy by DCC is remarkably enhanced by T6 heat treatment, which reached 308.5 MPa. Fracture surfaces of NZ30K alloy have been characterized as intergranular fracture by SMC and quasi-cleavage fracture by DCC, respectively.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  3. A low energy aqueous ammonia CO2 capture process

    DEFF Research Database (Denmark)

    Gaspar, Jozsef; Waseem Arshad, Muhammad; Blaker, Eirik Ask;

    2014-01-01

    by increasing temperature and L/G ratio but this leads to higher heat consumption, jeopardizing the economic feasibility. Here we developed, investigated, and optimized a novel CO2 capture process design using aqueous ammonia as solvent. The proposed configuration replaces the traditional stripper for solvent......The most pressing challenges regarding the use of ammonia for CO2 capture are the precipitation limitation and the energy penalty of solvent regeneration. Precipitation-free operation is a vital task since solids may cause the shutdown of the plant. Precipitation and slurry formation can be avoided...... with existing aqueous ammonia CO2 capture processes. Moreover, the thermal reactor can operate at 1 bar and 86 °C, therefore the NH3 regeneration temperature is reduced by approximately 50 qC. The integration of low- and mid- temperature waste heat becomes possible which can greatly improve the economics...

  4. Consumer acceptance of high pressure processed beef-based chilled ready meals: the mediating role of food-related lifestyle factors.

    Science.gov (United States)

    Sorenson, Douglas; Henchion, Maeve; Marcos, Begonya; Ward, Paddy; Mullen, Anne Maria; Allen, Paul

    2011-01-01

    The aim of this research was to investigate the effects of high pressure processing (HPP) on consumer acceptance for chilled ready meals manufactured using a low-value beef cut. Three hundred consumers evaluated chilled ready meals subjected to 4 pressure treatments and a non-treated control monadically on a 9-point scale for liking for beef tenderness and juiciness, overall flavour, overall liking, and purchase intent. Data were also collected on consumers' food consumption patterns, their attitudes towards food by means of the reduced food-related lifestyle (FRL) instrument, and socio-demographics. The results indicated that a pressure treatment of 200 MPa was acceptable to most consumers. K-means cluster analysis identified 4 consumer groups with similar preferences, and the optimal pressure treatments acceptable to specific consumer groups were identified for those firms that would wish to target attitudinally differentiated consumer segments.

  5. Ammonia removal from leachate by photochemical process using H2O2

    Directory of Open Access Journals (Sweden)

    Giovani Archanjo Brota

    2010-08-01

    Full Text Available In this work, it was studied the optimization of the photochemical process using H2O2/UV in order to reduce the concentration of ammonia in leachate. It was used landfills leachate previously treated in the development of studies. A photochemical reactor with the capacity of 1.7 liters equipped with refrigeration system and recirculation of leachate was employed in the research. The influence of temperature, the light bulb power, the concentration of H2O2 and treatment time were tested during the study. A removal of 97% of ammonia was observed at 90 min.

  6. Technological and economic update on the nitrate to ammonia and ceramic process

    International Nuclear Information System (INIS)

    The Nitrate to Ammonia and Ceramic (NAC) process, which was developed several years ago at the Oak Ridge National Laboratory (ORNL), still remains relatively unknown. This is despite its simplicity in converting nitrate or nitrite to ammonia gas at high efficiency while forming a very useful hydrated alumina-based solid that binds most metals and nonmetals. Two recent Department of Energy (DOE)-contracted total life-cycle cost analyses, related to treating nitrate-based wastes at Hanford, Savannah River, and Oak Ridge, have shown that the NAC technology is only one-third to one-fourth the cost of vitrification, electroreduction, steam reforming, and plasma arc

  7. High efficient ammonia heat pump system for industrial process water using the ISEC concept. Part 1

    DEFF Research Database (Denmark)

    Rothuizen, Erasmus Damgaard; Madsen, C.; Elmegaard, Brian;

    2014-01-01

    The purpose of the Isolated System Energy Charging (ISEC) is to provide a high-efficient ammonia heat pump system for hot water production. The ISEC concept uses two storage tanks for the water, one discharged and one charged. The charged tank is used for the industrial process while the discharged...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  10. Pretreatment of Process Condensate with Ammonia Degassing in CAN Fertilizer Production

    Directory of Open Access Journals (Sweden)

    Leaković, S.

    2011-10-01

    Full Text Available In the production process of calcium ammonium nitrate (CAN fertilizer, process-condensate is generated with a high content of ammonium nitrogen. Such high mass concentration of ammonium nitrogen (approximately 2 g L-1 significantly burdens the operation of the wastewater treatment plant, where the process condensate is treated by method of ion exchange. At CAN 1 Plant, a degassing system for process condensate was built. After pretreatment, the concentration of ammonium nitrogen in the process condensate was reduced to less than 500 mg L-1.Before upgrading with degassing system, the process condensate from CAN 1 Plant was collected in tank TK 17 301, from which it was pumped to the wastewater treatment plant to be treated by the method of ion exchange. When CAN 1 Plant is in normal operation, 10 m3h-1 of process condensate is formed with pH around 10, and temperatures around 50 °C. The degassing system of process condensate consists of a new tank, TK 17 504, which is connected with new pipeline to the tank TK 17 301. The process condensate input was transferred from the old to the new tank, TK 17 504. A new pump was installed for regulation of process condensate and bursting above the condensate level.Additional stimulation for ammonia degassing followed, after the return of 12 bar steam condensate into the tank TK 17 504. Consequently, the process condensate temperature increased to 80 C. Degassed ammonia is introduced into the existing system for washing gases and returns into the process of fertilizer production.By degassing ammonia from the process condensate at CAN 1 Plant, 10.7 kg h-1of ammonia returns into the fertilizer production process.Additionally, there has been an improved performance of the wastewater treatment plant, so that in December 2010, the volume of treated wastewater was almost 80 000 m3 which is an increase of 86 %.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. Chilled beam application guidebook

    CERN Document Server

    Butler, David; Gräslund, Jonas; Hogeling, Jaap; Lund Kristiansen, Erik; Reinikanen, Mika; Svensson, Gunnar

    2007-01-01

    Chilled beam systems are primarily used for cooling and ventilation in spaces, which appreciate good indoor environmental quality and individual space control. Active chilled beams are connected to the ventilation ductwork, high temperature cold water, and when desired, low temperature hot water system. Primary air supply induces room air to be recirculated through the heat exchanger of the chilled beam. In order to cool or heat the room either cold or warm water is cycled through the heat exchanger.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  15. 冰鲜鸭加工车间的菌相变化分析%Microflora changes of chilled duck at processing plants

    Institute of Scientific and Technical Information of China (English)

    王华伟; 刘芳; 王道营; 诸永志; 徐幸莲; 徐为民

    2013-01-01

    应用传统微生物培养和聚合酶链反应-变性梯度凝胶电泳(PCR-DGGE)技术,综合分析冰鲜鸭加工中主要工序点的菌相变化.同时对车间环境包括车间空气、工人手面、案板、胴体表面以及预冷水进行污染调查,并通过PCR-DGGE研究车间环境菌种的多样性.结果表明:影响冰鲜鸭产品微生物污染状况的主要来源为净膛间,主要菌种有Aeromonas veronii、Macrococcus caseolyticus、Acinetobacter lwoffii、Shewanella baltica、Enhydrobacter aerosaccus、Rothia mucilaginosa以及Staphylococcus 属;直接来源为二阶预冷水,主要菌种为Aeromonas veronii、Enhydrobacter aerosaccus、Pseudomonas fluorescens、Shewanella baltica 和Acinetobacter lwoffii,与产品菌种组成相同.前区与后区的隔离对降低后区微生物污染起到关键作用,净膛工序和预冷工序是影响产品微生物指标的关键.%Assisted with traditional microbial culture and polymerase chain reaction-denaturing gradient gel electrophoresis ( PCR-DGGE) technology,the microflora changes of chilled duck at major processing steps were detected. The microbiological contamination of air, workers' hands, table, carcass surface and pre-chilling water was assayed with conventional culture method and the diversity of microbes was analyzed with PCR-DGGE technology. Taken together.it showed that the main contamination source of the product was eviscerating plant,with the major strains being Aeromonas veronii,Macrococcus caseolyticus,Acinetobacter lwoffii,Shewanella baltica, Enhydrobacter aerosaccus ,Rothia mucilaginosa and Staphylococcus, and the direct contamination source was the second stage pre-chilling water,with the major strains being Aeromonas veronii,Enhydrobacter aerosaccus,Pseudomonas fluorescens,Shewanella baltica and Acinetobacter Iwqffii, which were identical with the strain composition of the products. The separation of products between front area and back area had a critical effect on

  16. Effects of Different Concentrations of Ammonia Nitrogen on N_2O Emission in the Process of Partial Nitrification

    Institute of Scientific and Technical Information of China (English)

    TIAN; Lin; KONG; Qiang; ZHANG; Jian; MIAO; Ming-sheng

    2012-01-01

    [Objective] The study aimed to discuss the effects of different concentrations of ammonia nitrogen on N2O emission in the process of partial nitrification. [Method] By using a sequencing batch biofilm reactor (SBBR) under intermittent aeration, the influences of various concentrations of influent ammonia nitrogen on nitrous oxide (N2O) emission from partial nitrification were analyzed. [Result] When the concentration of influent ammonia nitrogen varied from 200 to 400 mg/L, the changing trends of DO and ORP value were consistent during the process of partial nitrification, and the concentration ratio of NO-2-N to NH+4-N in effluent water reached 1∶1, with lower NO-3-N level. In addition, ammonia nitrogen concentration in the influent had significant effects on N2O emission in the process of partial nitrification, that is, the higher the ammonia nitrogen concentration, the more the N2O emission. When ammonia nitrogen concentration was 400 mg/L, N2O emission was up to about 37 mg. [Conclusion] N2O emission in the process of partial nitrification might be related to the concentrations of NH+4 and NO-2.

  17. Effects of Different Concentrations of Ammonia Nitrogen on N2O Emission in the Process of Partial Nitrification

    Institute of Scientific and Technical Information of China (English)

    TIAN; Lin; KONG; Qiang; ZHANG; Jian; MIAO; Ming-sheng

    2012-01-01

    [Objective] The study aimed to discuss the effects of different concentrations of ammonia nitrogen on N2O emission in the process of partial nitrification. [Method] By using a sequencing batch biofilm reactor (SBBR) under intermittent aeration, the influences of various concentrations of influent ammonia nitrogen on nitrous oxide (N2O) emission from partial nitrification were analyzed. [Result] When the concentration of influent ammonia nitrogen varied from 200 to 400 mg/L, the changing trends of DO and ORP value were consistent during the process of partial nitrification, and the concentration ratio of NO-2-N to NH+4-N in effluent water reached 1∶1, with lower NO-3-N level. In addition, ammonia nitrogen concentration in the influent had significant effects on N2O emission in the process of partial nitrification, that is, the higher the ammonia nitrogen concentration, the more the N2O emission. When ammonia nitrogen concentration was 400 mg/L, N2O emission was up to about 37 mg. [Conclusion] N2O emission in the process of partial nitrification might be related to the concentrations of NH+4 and NO-2.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    Chilling temperatures (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. Process simulation of CO2 capture with aqueous ammonia using the Extended UNIQUAC model

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; Maribo-Mogensen, Bjørn; van Well, Willy J.M.;

    2012-01-01

    of the process is necessary.In this work, the performance of the carbon dioxide capture process using aqueous ammonia has been analyzed by process simulation. The Extended UNIQUAC thermodynamic model available for the CO2–NH3–H2O system has been implemented in the commercial simulator Aspen Plus®1 by using...

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

    Science.gov (United States)

    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

  3. Influence of dielectric constant of polymerization medium on processability and ammonia gas sensing properties of polyaniline

    Indian Academy of Sciences (India)

    Partha Pratim Sengupta; Pradip Kar; Basudam Adhikari

    2011-04-01

    Polyaniline (PANI) was synthesized by the oxidation of aniline hydrochloride in the presence of ammonium persulphate and hydrochloric acid. The polymerization reaction was carried out in several batches in different solvent media by changing the volume ratio of ,-dimethyl formamide (DMF) and water as binary solvent mixture. The dielectric constant of the polymerizationmedium for each batch reaction was determined by measuring the capacitance with change in frequency. The UV spectra of the synthesized polyaniline solutions helped us to optimize the ratio of the binary solvent to get sufficient polymer growth and processability. Thin film of processable polyaniline was then deposited on glass slides coated with polyvinyl alcohol (PVA) crosslinked with maleic anhydride (MA). FTIR and XRD studies of the coated film were also done. AFM studies further helped in the morphological study of the film deposited. Finally, conductivity and ammonia gas-sensing property of the polyaniline film were also studied.

  4. Ammonia-based feedforward and feedback aeration control in activated sludge processes.

    Science.gov (United States)

    Rieger, Leiv; Jones, Richard M; Dold, Peter L; Bott, Charles B

    2014-01-01

    Aeration control at wastewater treatment plants based on ammonia as the controlled variable is applied for one of two reasons: (1) to reduce aeration costs, or (2) to reduce peaks in effluent ammonia. Aeration limitation has proven to result in significant energy savings, may reduce external carbon addition, and can improve denitrification and biological phosphorus (bio-P) performance. Ammonia control for limiting aeration has been based mainly on feedback control to constrain complete nitrification by maintaining approximately one to two milligrams of nitrogen per liter of ammonia in the effluent. Increased attention has been given to feedforward ammonia control, where aeration control is based on monitoring influent ammonia load. Typically, the intent is to anticipate the impact of sudden load changes, and thereby reduce effluent ammonia peaks. This paper evaluates the fundamentals of ammonia control with a primary focus on feedforward control concepts. A case study discussion is presented that reviews different ammonia-based control approaches. In most instances, feedback control meets the objectives for both aeration limitation and containment of effluent ammonia peaks. Feedforward control, applied specifically for switching aeration on or off in swing zones, can be beneficial when the plant encounters particularly unusual influent disturbances.

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

    Directory of Open Access Journals (Sweden)

    Fortelný Zdeněk

    2012-04-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Arteca, Gustavo A. [Departement de Chimie et Biochimie and Biomolecular Sciences Programme, Laurentian University, Ramsey Lake Road, Sudbury, Ontario, Canada P3E 2C6 (Canada); Department of Physical Chemistry, Uppsala University, A ring ngstroemlaboratoriet, Box 259, S-751 05 Uppsala (Sweden); Tapia, O. [Department of Physical Chemistry, Uppsala University, A ring ngstroemlaboratoriet, Box 259, S-751 05 Uppsala (Sweden)

    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.

  9. Optimization on refreshment process in chilled meat hurdle preservative technology%冷却肉栅栏保鲜工艺优化

    Institute of Scientific and Technical Information of China (English)

    张根生; 姜艳; 张毅超; 姚烨

    2015-01-01

    目的:以新鲜猪肉为原料,开发一种能延长冷却肉货架期的保鲜工艺。方法根据栅栏因子理论选取3种栅栏因子,研究低温冷藏、紫外灭菌和天然保鲜液对冷却肉综合保鲜的影响。在单因素基础上,通过正交试验,以菌落总数和挥发性盐基氮(TVB-N)值为评价指标。结果紫外灭菌(20 W、90 s和30 cm)+天然保鲜液配方(ε-聚赖氨酸0.5%、茶多酚1.75%和植酸0.3%)能在4℃保存18 d。结论根据栅栏技术因子保鲜理论,采用多种栅栏因子的科学组合能有效将货架期从4 d延长至18 d。%ABSTRACT:Objective To develop a new technology for prolonging the shelf life of chilled meat using fresh pork as raw material.Methods According to the theory of barrier factors, 3 kinds of barrier factors were selected to study the effect of low temperature, UV-C, and natural fresh keeping agents on the preservation of chilled meat. Based on the single factor, the total numbers of colony and total volatile basic nitrogen (TVB-N) were evaluated by orthogonal test.Results After process of UV-contamination control (20 W, 90 s, 30 cm)+natural preservation fluid formulations (ε-polylysine 0.5%, tea polyphenol 1.75% and phytic acid 0.3%) + vacuum packaging, products could maintain refresh under refrigerated (4℃ ) for 18 d without corruption or deterioration.Conclusion Based on the theory of the technology factor of the fence, the combination of a va-riety of fence factor can effectively extend the shelf life from 4 d to 18 d.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

  13. Phenols in anaerobic digestion processes and inhibition of ammonia oxidising bacteria (AOB) in soil

    International Nuclear Information System (INIS)

    This study focuses on the presence of phenols in digestate from seven Swedish large-scale anaerobic digestion processes and their impact on the activity of ammonia oxidising bacteria (AOB) in soil. In addition, the importance of feedstock composition and phenol degradation capacity for the occurrence of phenols in the digestate was investigated in the same processes. The results revealed that the content of phenols in the digestate was related to the inhibition of the activity of AOB in soil (EC5 = 26 μg phenols g-1 d.w. soil). In addition, five pure phenols (phenol, o-, p-, m-cresol and 4-ethylphenol) inhibited the AOB to a similar extent (EC5 = 43-110 μg g-1 d.w. soil). The phenol content in the digestate was mainly dependent on the composition of the feedstock, but also to some extent by the degradation capacity in the anaerobic digestion process. Swine manure in the feedstock resulted in digestate containing higher amounts of phenols than digestate from reactors with less or no swine manure in the feedstock. The degradation capacity of phenol and p-cresol was studied in diluted small-scale batch cultures and revealed that anaerobic digestion at mesophilic temperatures generally exhibited a higher degradation capacity compared to digestion at thermophilic temperature. Although phenol, p-cresol and 4-ethylphenol were quickly degraded in soil, the phenols added with the digestate constitute an environmental risk according to the guideline values for contaminated soils set by the Swedish Environmental Protection Agency. In conclusion, the management of anaerobic digestion processes is of decisive importance for the production of digestate with low amounts of phenols, and thereby little risks for negative effects of the phenols on the soil ecosystem

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

    Science.gov (United States)

    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.

  15. Biogenic amine formation and nitrite reactions in meat batter as affected by high-pressure processing and chilled storage.

    Science.gov (United States)

    Ruiz-Capillas, C; Aller-Guiote, P; Carballo, J; Colmenero, F Jiménez

    2006-12-27

    Changes in biogenic amine formation and nitrite depletion in meat batters as affected by pressure-temperature combinations (300 MPa/30 min/7, 20, and 40 degrees C), cooking process (70 degrees C/30 min), and storage (54 days/2 degrees C) were studied. Changes in residual nitrite concentration in raw meat batters were conditioned by the temperature and not by the pressure applied. Cooking process decreased (P batters. High-pressure processing conditions had no effect on the rate of residual nitrite loss throughout the storage. The application of high pressure decreased (P < 0.05) the concentration of some biogenic amines (tyramine, agmatine, and spermine). Irrespective of the high processing conditions, generally, throughout storage biogenic amine levels did not change or increased, although quantitatively this effect was not very important.

  16. [Climatic risk zoning for banana and litchi's chilling injury in South China].

    Science.gov (United States)

    Li, Na; Huo, Zhi-guo; He, Nan; Xiao, Jing-jing; Wen, Quan-pei

    2010-05-01

    Based on the 1951-2006 climatic observation data from 224 meteorological stations in South China (Guangdong Province, Guangxi Autonomous Region, and Fujian Province) and the historical information about the chilling injury losses of banana and litchi, the accumulated harmful chilling for the processes with minimum daily temperature banana and litchi's chilling injury were drawn, and the spatial variation of climatic risk for banana and litchi's chilling injury was commented. The results indicated that in the study area, climate warming might lead to the decrease of cold resistance of banana and litchi, which could increase the disaster risk of chilling injury. The geographical distribution of climatic risk probability for banana and litchi's chilling injury showed a zonal pattern. According to the integrated climatic risk index, the banana and litchi's chilling injury region was divided into three risk types, i.e., high risk, moderate risk, and low risk, which provided an important basis for the adjustment of agricultural production structure.

  17. A zirconium dioxide ammonia microsensor integrated with a readout circuit manufactured using the 0.18 μm CMOS process.

    Science.gov (United States)

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

    2013-03-15

    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.

  18. 5A Zirconium Dioxide Ammonia Microsensor Integrated with a Readout Circuit Manufactured Using the 0.18 μm CMOS Process

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Ming-Zhi Yang

    2013-03-01

    Full Text Available 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.

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

    Directory of Open Access Journals (Sweden)

    A. Móring

    2015-07-01

    Full Text Available 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 3 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 can be obtained for study at larger scales, GAG is potentially suitable for larger scale application, such as

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

    Science.gov (United States)

    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 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 can be obtained for study at larger scales, GAG is potentially suitable for larger scale application, such as in regional atmospheric and ecosystem models.

  2. Stable isotope composition of biogas allows early warning of complete process failure as a result of ammonia inhibition in anaerobic digesters.

    Science.gov (United States)

    Lv, Zuopeng; Hu, Meng; Harms, Hauke; Richnow, Hans Hermann; Liebetrau, Jan; Nikolausz, Marcell

    2014-09-01

    Four 15-L lab-scale continuous stirred tank reactors were operated under mesophilic conditions to investigate the effect of ammonia inhibition. Stable isotope fingerprinting of biogas was applied as a process monitoring tool. Ammonia inhibition was initiated by amendment of chicken manure to maize silage fed reactors. During the accumulation of ammonia, the concentration of volatile fatty acids increased while the biogas production and pH decreased. However, in one reactor, an inhibited steady state with stable gas production even at high ammonia levels was achieved, while the other reactor proceeded to complete process failure. A depletion of the δ(13)CH4 and δ(13)CO2 values preceded the process inhibition. Moreover, the stable isotope composition of biogas also forecasted the complete process failure earlier than other standard parameters. The stable isotope analyses of biogas have a potential for mechanistic insights in anaerobic processes, and may be used to pre-warn process failure under stress conditions.

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

    Science.gov (United States)

    Kim, Ji-Han; Hong, Go-Eun; Lim, Ki-Won; Park, Woojoon; Lee, Chi-Ho

    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 (pacid 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 (pcitric acid concentrations.

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

    Science.gov (United States)

    Kim, Ji-Han; Hong, Go-Eun; Lim, Ki-Won; Park, Woojoon; Lee, Chi-Ho

    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 (psous vide chicken breast at 2% and 5% citric acid concentrations. PMID:26761885

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

    Science.gov (United States)

    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...

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

    DEFF Research Database (Denmark)

    Wang, Han; Fotidis, Ioannis; Angelidaki, Irini

    2016-01-01

    uninhibited production, respectively. At the same time control reactor (RCTL), 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...

  7. Welding Using Chilled-Inert-Gas Purging

    Science.gov (United States)

    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.

  8. 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

    International Nuclear Information System (INIS)

    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 85Sr and 137Cs. Despite lengthy counting times, 85Sr could not be detected in the leachates. 137Cs 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

  9. Implementation of flowsheet change to minimize hydrogen and ammonia generation during chemical processing of high level waste in the defense waste processing facility

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, Dan P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Woodham, Wesley H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Williams, Matthew S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Newell, J. David [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Luther, Michelle C. [Auburn Univ., AL (United States); Brandenburg, Clayton H. [Univ.of South Carolina, Columbia, SC (United States)

    2016-09-27

    Testing was completed to develop a chemical processing flowsheet for the Defense Waste Processing Facility (DWPF), designed to vitrify and stabilize high level radioactive waste. DWPF processing uses a reducing acid (formic acid) and an oxidizing acid (nitric acid) to rheologically thin the slurry and complete the necessary acid base and reduction reactions (primarily mercury and manganese). Formic acid reduces mercuric oxide to elemental mercury, allowing the mercury to be removed during the boiling phase of processing through steam stripping. In runs with active catalysts, formic acid can decompose to hydrogen and nitrate can be reduced to ammonia, both flammable gases, due to rhodium and ruthenium catalysis. Replacement of formic acid with glycolic acid eliminates the generation of rhodium- and ruthenium-catalyzed hydrogen and ammonia. In addition, mercury reduction is still effective with glycolic acid. Hydrogen, ammonia and mercury are discussed in the body of the report. Ten abbreviated tests were completed to develop the operating window for implementation of the flowsheet and determine the impact of changes in acid stoichiometry and the blend of nitric and glycolic acid as it impacts various processing variables over a wide processing region. Three full-length 4-L lab-scale simulations demonstrated the viability of the flowsheet under planned operating conditions. The flowsheet is planned for implementation in early 2017.

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

    DEFF Research Database (Denmark)

    Móring, Andrea; Vieno, Massimo; M. Doherty, Ruth;

    2016-01-01

    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...

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

    Science.gov (United States)

    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

  12. Quality effect of freeze-chilling in cod and rainbow trout

    DEFF Research Database (Denmark)

    Jensen, Louise Helene Søgaard; Nielsen, Jette; Jørgensen, Bo;

    staff combines the different meal components to a complete meal. Freeze-chilling is a process consisting of freezing and frozen storage followed by thawing and chilled storage and could be an ideal technique to combine with the concept of meal elements. Freeze-chilling would enable manufacturers...... to produce large quantities of frozen meal elements to be released into the chill chain according to market demands. This procedure would allow the products to thaw during transport, and by arrival the thawed meal elements would be ready for use or chill storage. We have studied the influence of freeze...... is practically applicable and cod and rainbow trout seem potential candidates for freeze-chilled meal elements....

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

    Science.gov (United States)

    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.

  14. Effect of tryptone and ammonia on the biogas process in continuously stirred tank reactors treating cattle manure

    DEFF Research Database (Denmark)

    Nielsen, Hanne Bjerg; Ahring, Birgitte Kiær

    2007-01-01

    Two themophilic continuously stirred tank reactors, R1 and Two thermophilic continuously stirred tank reactors, R1 and R2, were subject to pulses of tryptone and ammonia. R1 was operated at an ammonia-N concentration of 3.0 g l(-1) and R2 was operated at an ammonia-N concentration of 1.7 g l(-1)....

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  17. Redox Signaling and CBF-Responsive Pathway Are Involved in Salicylic Acid-Improved Photosynthesis and Growth under Chilling Stress in Watermelon

    Science.gov (United States)

    Cheng, Fei; Lu, Junyang; Gao, Min; Shi, Kai; Kong, Qiusheng; Huang, Yuan; Bie, Zhilong

    2016-01-01

    Salicylic acid (SA) plays an important role in plant response to abiotic stresses. This study investigated the potential role of SA in alleviating the adverse effects of chilling stress on photosynthesis and growth in watermelon (Citrullus lanatus). Chilling stress induced the simultaneous accumulation of free and conjugated SA in watermelon plants, and the chilling-induced SA production was attributed to the phenylalanine ammonia-lyase pathway. Applying SA at moderate concentrations induced chilling tolerance, whereas inhibition of SA biosynthesis by L-α-aminooxy-β-phenylpropionic acid (AOPP) increased the photooxidation of PS II under chilling stress in watermelon, resulting in reduced photosynthesis and growth. Chilling induced a transient increase in the ratios of reduced to oxidized glutathione and reduced ascorbate to dehydroascorbate. Then, the expression of antioxidant genes was upregulated, and the activities of antioxidant enzymes were enhanced. Furthermore, SA-induced chilling tolerance was associated with cellular glutathione and ascorbate homeostasis, which served as redox signals to regulate antioxidant metabolism under chilling stress. AOPP treatment stimulated the chilling-induced expression of cold-responsive genes, particularly via C-repeat binding factors CBF3 and CBF4. These results confirm the synergistic role of SA signaling and the CBF-dependent responsive pathway during chilling stress in watermelon. PMID:27777580

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

    Science.gov (United States)

    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.

  19. 钴渣氨浸工艺的研究%Studies on Process for Ammonia Leaching of Cobalt Dregs

    Institute of Scientific and Technical Information of China (English)

    王开毅; 蔡春林; 钱东; 李涛; 陈小毅; 赖德勇

    2001-01-01

    The process for ammonia leaching of cobalt dregs was studied. In the course of ammonia leaching of cobalt dregs, the yield of cobalt can increase greatly when cobaltic(Ⅲ) is reduced to coboltous(Ⅱ) by the reductant such as sodium sulfite. In the experiment,when the concentration of ammonia water is 14%,the concentration of ammonium sulfate is 160 g/L and the ratio of liquid-solid is 8∶1, the cobalt dregs were reacted with leaching solution for 30 min at 70℃. Then double ammount of the reductant sodium sulfite with respect to the amount of cobalt (mol ratio) was added and the leaching reaction was continued for another 5 h at 50℃. The yield of cobalt and nickel are 97.46% and 95.00%, respectively.%研究了钴渣的氨浸工艺.在钴渣氨浸过程中,用亚硫酸钠将钴渣中三价钴还原成二价钴,可较大程度地提高钴的浸出率.实验中,在氨水浓度为 14%,硫酸铵浓度为 160 g/L,液固比为 8∶1条件下,浸出液与钴渣在 70℃下反应 30 min,然后加入二倍钴量(摩尔比)的还原剂亚硫酸钠于 50℃下浸出 5 h,钴的浸出率达到了 97.46%,镍的浸出率为 95.00%.

  20. Cod and rainbow trout as freeze-chilled meal elements

    DEFF Research Database (Denmark)

    Jensen, Louise Helene Søgaard; Nielsen, Jette; Jørgensen, Bo;

    2010-01-01

    Meal elements' are elements of a meal, e.g. portions of pre-fried meat, sauces, frozen fish or pre-processed vegetables typically prepared industrially. The meal elements are distributed to professional satellite kitchens, where the staff can combine them into complete meals. Freeze-chilling is a......Meal elements' are elements of a meal, e.g. portions of pre-fried meat, sauces, frozen fish or pre-processed vegetables typically prepared industrially. The meal elements are distributed to professional satellite kitchens, where the staff can combine them into complete meals. Freeze......-chilling is a process consisting of freezing and frozen storage followed by thawing and chilled storage. Combining the two would enable the manufacturer to produce large quantities of frozen meal elements to be released into the chill chain according to demand. We have studied the influence of freeze...... and cod and rainbow trout seem potential candidates for freeze-chilled meal elements. (C) 2009 Society of Chemical Industry...

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

    Science.gov (United States)

    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.

  2. Distribution and rate of microbial processes in ammonia-loaded air filter biofilm

    DEFF Research Database (Denmark)

    Juhler, Susanne; Nielsen, Lars Peter; Schramm, Andreas;

    2009-01-01

    The in situ activity and distribution of heterotrophic and nitrifying bacteria and their potential interactions were investigated in a full-scale, two-section, trickling filter designed for biological degradation of volatile organics and NH3 in ventilation air from pig farms. The filter biofilm...... was investigated by microsensor analysis, fluorescence in situ hybridization, quantitative PCR, and batch incubation activity measurements. In situ aerobic activity showed a significant decrease through the filter, while the distribution of ammonia-oxidizing bacteria (AOB) was highly skewed toward the filter...... with heterotrophic bacteria for O2 and inhibition by the protonated form of NO2-, HNO2. Product inhibition of AOB growth could explain why this type of filter tends to emit air with a rather constant NH3 concentration irrespective of variations in inlet concentration and airflow....

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

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

    2014-07-01

    Pelletization process variables, including grind size (4, 6mm), die speed (40, 50, 60 Hz), and preheating (none, 70°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 (6mm) had similar or lower sugar yields. Pellets generated with 4mm AFEX-treated corn stover, a 60Hz die speed, and no preheating resulted in pellets with similar or greater density, durability, and sugar yields compared to other pelletization conditions.

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

    Energy Technology Data Exchange (ETDEWEB)

    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. Analysis and improvement of ammonia stripping process by heat transfer oil%导热油蒸氨工艺分析与改进

    Institute of Scientific and Technical Information of China (English)

    张利杰

    2016-01-01

    The problems in ammonia stripping process by heat transfer oil is analyzed. After improve-ment, the efficiency of ammonia stripping is increased, the index of waste water is stabilized and maintenance costs of the equipment are lowered.%分析了导热油蒸氨工艺存在的问题,改进后提高了蒸氨效率,稳定了废水指标,降低了蒸氨系统的设备维修费用。

  7. Process Optimization of Ammonia Steam Heating System in Coking Plant%焦化厂蒸氨供热系统工艺优化

    Institute of Scientific and Technical Information of China (English)

    苏琼

    2015-01-01

    主要阐述了焦化厂蒸氨塔供热系统工艺优化方案,介绍了蒸汽喷射热泵在蒸氨系统中的应用。运行结果证明,蒸氨塔供热系统工艺优化后取得了良好的节能降耗效果。%The process optimization of ammonia distil ation tower heating system is elaborated.And the application of steam injection hot pump in ammonia steam system is introduced.The running results show that good energy saving effect is achieved after the optimization of ammonia distil ation tower heating system.

  8. The Technical Characteristics and Comparison of New Ammonia Synthesis Process%新型氨合成工艺技术的特点及比较

    Institute of Scientific and Technical Information of China (English)

    张占一

    2011-01-01

    The supply and demand of synthetic ammonia in domestic market is briefly overviewed in this paper,while several kinds of new ammonia synthesis process and flow is introduced in details,with the analysis and comparison of different technical characteristics and the prospect of the development trend of synthetic ammonia industry in our country.%分析了国内合成氨的市场供需概况;介绍了几种新型氨合成工艺技术、装置特点和工艺流程;以50万t/a合成氨生产装置为例,对比了KBR、托普索、卡萨利氨合成工艺的综合技术参数;展望了我国合成氨工艺技术的发展趋势。

  9. 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

    Science.gov (United States)

    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...

  10. The Relationships between Rheological Properties and Structural Changes of Chilled Abalone Meat

    Institute of Scientific and Technical Information of China (English)

    GAO Xin; ZHANG Zhaohui; TANG Zhixu; TASHIRO Yuri; OGAWA Hiroo

    2003-01-01

    The quantitative correlation between theological properties and structural characteristic values of chilled abalone meat was studied. Structural changes were observed, and these values were enumerated using image processing and analysis technique. Structural changes in the myofibrils and collagen fibrils were the greatest in chilling for 24 h. After chilling for 48 h, similar structures of vertical and cross sections were observed. For chilling from 0h to 72h, the instantaneous modulus E0 of the both section meat decreases gradually with time, but no significant differences were observed after chilling for 48 h.The relaxation time and viscosity of both sections attained the same values for the same chilling time, but increased gradually with increasing chilling time. Meanwhile, a negative correlation between the structural characteristic values (Dm, Am,Rvm), and rheological properties (E1,τi,η1) clearly exists. Some logarithmic expressions have been obtained for these negative correlations. These results suggest that the difference in rheological properties between the cross and vertical sections was mainly due to the structural changes of myofibrils and collagen fibrils, and rheological properties are influenced quantitatively by the structural characteristic values for chilling from 0 h to 72 h.

  11. THE EFFECTS OF SPRAY-CHILLING ASSOCIATED TO CONVENTIONAL CHILLING ON MASS LOSS, BACTERIOLOGYCAL AND PHYSICO-CHEMICAL QUALITY OF BEEF CARCASS

    Directory of Open Access Journals (Sweden)

    Moacir Evandro Lage

    2006-10-01

    Full Text Available The purpose of this study was to verify the effect of conventional air chilling associated to intermittent spray-chilling treatment, on weight loss, physico-chemical and bacteriological quality of beef carcasses. Two plants of commercial beef slaughterhouse located in Goiânia and fiscalized by the Federal Inspection Service were used to develop the research. The spray-chilling treatment was accomplished in an intermittent way, commanded by acontrolled logical program, with cycles of 90 seconds, in intervals of 30 minutes, during the first 4 hours of the chilling process. Physico-chemical and bacteriological analysis were made in spray-chilled water and carcasses samples, according to recommendation of the effective legislation.The average values of carcasses weight loss of treatment group were lower to the ones verified for the control group,in both plants, A and B, (P < 0,001, showing a high economic potential. As a conclusion of physico-chemical and bacteriological analysis results of water and meat samples, it is clear that the technology of chilling beef carcasses inthe conventional system associated to spraying did not interfere in the quality of meat, and it can become an analysis object on part of official organs for sanitary regulation and fiscalization, for its definitive adoption. KEY WORDS: Spray-chilling, shrinkage, beef carcass.

  12. Morphological and chemical study of the initial growth of CdS thin films deposited using an ammonia-free chemical process

    Energy Technology Data Exchange (ETDEWEB)

    Mazon-Montijo, D.A.; Sotelo-Lerma, M.; Quevedo-Lopez, M. [Centro de Investigacion en Polimeros y Materiales, Universidad de Sonora, Apdo. Postal 130, 83190 Hermosillo, Son. (Mexico); El-Bouanani, M. [Department of Materials Science and Engineering, University of North Texas, P.O. Box 305310 Denton, TX 76203-5310 (United States); Alshareef, H.N. [SEMATECH, 2706 Montopolis Drive, Austin, TX 78741 (United States); Espinoza-Beltran, F.J. [Centro de Investigacion y Estudios Avanzados del IPN, Unidad Queretaro, Apdo. Postal 1-798, 76001 Queretaro, Qro. (Mexico); Ramirez-Bon, R. [Centro de Investigacion y Estudios Avanzados del IPN, Unidad Queretaro, Apdo. Postal 1-798, 76001 Queretaro, Qro. (Mexico)], E-mail: rrbon@qro.cinvestav.mx

    2007-11-15

    We study the initial growth stages of CdS thin films deposited by an ammonia-free chemical bath deposition process. This ammonia-free process is more environmentally benign because it reduces potential ammonia release to the environment due to its high volatility. Instead of ammonia, sodium citrate was used as the complexing agent. We used atomic force microscopy (AFM), Rutherford backscattering (RBS) and X-ray photoelectron spectroscopy (XPS) to investigate the morphological and chemical modifications at the substrate surface during the first initial stages of the CdS deposition process. Additionally, X-ray diffraction (XRD) and optical transmission spectroscopy measurements were carried out to compliment the study. XPS results show that the first nucleation centers are composed by Cd(OH){sub 2} which agglomerate in patterns of bands, as demonstrated by AFM results. It is also observed that the conversion to CdS (by anionic exchange) of the first nucleus begins before the substrate surface is completely covered by a homogenous film.

  13. Parameter Optimization on Experimental Study to Reduce Ammonia Escape in CO2 Absorption by Ammonia Scrubbing

    Institute of Scientific and Technical Information of China (English)

    Hao Leng; Jianmin Gao; Mingyue He; Min Xie; Qian Du; Rui Sun; Shaohua Wu

    2016-01-01

    In order to research ammonia escape in CO2 absorption by ammonia scrubbing, ammonia escape was studied in CO2 absorption process using the bubbling reactor in different conditions as gas flow rate, CO2 ratio, absorbent temperature and ammonia concentration and quantity of escaped ammonia was measured by chemical titration. The results indicated that, the amount of ammonia escape can be around 20% of original amount in 90 min and the escaped amount will increase with the rise of gas flow rate, absorbent temperature, concentration of ammonia while decrease as CO2 ratio goes up. Through the analysis of the law of ammonia escape, at the same time, combined with ammonia escape and the influence of the relationship between the CO2 absorption efficiency, reducing ammonia escape working condition parameter optimization is given.

  14. Deammonification in the moving-bed process for the treatment of wastewater with high ammonia content

    Energy Technology Data Exchange (ETDEWEB)

    Rosenwinkel, K.H.; Cornelius, A. [Institut fuer Siedlungswasserwirtschaft und Abfalltechnik der Universitaet Hannover (ISAH), Welfengarten 1, D-30167 Hannover (Germany)

    2005-01-01

    The process of deammonification for the biological treatment of sludge water was investigated in a full-scale pilot plant at Hattingen, Germany. Since deammonification is a completely autotrophic process, no organic carbon is needed for bacteria growth. So, deammonification is an attractive and cost-effective process for the treatment of wastewater with unfavorable COD/N ratio without using an external carbon source. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  15. Anammox for ammonia removal from pig manure effluents: Effect of organic matter content on process performance

    DEFF Research Database (Denmark)

    Salces, Beatriz Molinuevo; García, M. C.; Karakashev, Dimitar Borisov;

    2009-01-01

    The anammox process, under different organic loading rates (COD), was evaluated using a semi-continous UASB reactor at 37 degrees C. Three different substrates were used: initially, synthetic wastewater, and later, two different pig manure effluents (after UASB-post-digestion and after partial...... (from 95 mg COD L-1 to 237 mg COD L-1 and from 121 mg COD L-1 to 290 mg COD L-1 for the UASB-post-digested effluent and the partially oxidized effluent, respectively) negatively affected the anammox process and facilitated heterotrophic denitrification. Partial oxidation as a pre-treatment method...... and anammox process were simultaneously occurring in the reactor. Denitrification became the dominant ammonium removal process when the COD loading was increased....

  16. A Systematic Approach for Conceptual and Sustainable Process Design: Production of Methylamines From Methanol and Ammonia

    DEFF Research Database (Denmark)

    Mansouri, Seyed Soheil; Ismail, Muhammad Imran Bin; Almoor, Karim

    2012-01-01

    and LCA measures such as sustainability metrics for environment, economic and social; carbon footprint; safety index and many more. In addition, PRO/II is used for process simulation (for verification of design), ICAS for property prediction and analysis of design options; ECON for cost and economic......Methylamines are very important chemicals as they are commonly used as intermediates for a wide range of agricultural chemicals, animal nutrients, catalysts, electronics, explosives, fuel additives as well as gas and oil treatments. A systematic method is applied to design a sustainable...... of the process flow sheet and preliminary calculations to the detailed process simulations, equipment sizing, costing, an economic evaluation, and sustainability of the designed process. At the end of task-9, the base case design is obtained, which is then further refined and improved with respect to heat...

  17. Low Energy Consumption Technique for Processing Rapeseed with Two-phase Extraction System without Ammonia

    Institute of Scientific and Technical Information of China (English)

    Shi Meiren; Qin Jinping; SQian Renyuan

    2000-01-01

    the mother liquid of methanol phase obtained from rapeseed two-phase extraction process can directly be reused in large amounts to process rapeseed again together with some fresh methanol phase, so long as it is treated with a litter of proper additives in advance. The ratio of the reused mother liquid may be more than 3/ 4 of the total amount of the methanol phase needed for processing rapeseed, so the energy consumption can be decreased tremendously. The meal obtained by use of the reused mother liquid keeps the quality as good as those obtained by use of totally fresh methanol phase with light color, weak taste, crispness, good palatability, high protein content, and a low level of glucosinolates much more less than that stipulated by the State for the fodder of grade A.

  18. Low Energy Consumption Technique for Processing Rapeseed with Two—phase Extraction System without Ammonia

    Institute of Scientific and Technical Information of China (English)

    ShiMeiren; QinJinping; 等

    2000-01-01

    The mother liquid of methanol phase obtained from rapeseed two-phase extraction process can directly be reused in large amounts to process rapeseed again together with some fresh methanol phase,so long as it is treated with a litter of proper additives in advance.The ratio of the reused mother liquid may be more than 3/4 of the total amount of the methanol phase needed for processing rapeseed,so the energy consumption can be decreased tremendously.The meal obtained by use of the reused mother liquid keeps the quality as good as those obtained by use of totally fresh methanol phase with light color,weak taste,crispness,good palatability,high protein content,and a low level of glu-cosinolates much more less than that stipulated by the State for the fodder of grade A.

  19. Niche specialization of terrestrial archaeal ammonia oxidizers

    OpenAIRE

    Gubry-Rangin, Cécile; Hai, Brigitte; Quince, Christopher; Engel, Marion; Thomson, Bruce C.; James, Phillip; Schloter, Michael; Robert I. Griffiths; Prosser, James I.; Nicol, Graeme W.

    2011-01-01

    Soil pH is a major determinant of microbial ecosystem processes and potentially a major driver of evolution, adaptation, and diversity of ammonia oxidizers, which control soil nitrification. Archaea are major components of soil microbial communities and contribute significantly to ammonia oxidation in some soils. To determine whether pH drives evolutionary adaptation and community structure of soil archaeal ammonia oxidizers, sequences of amoA, a key functional gene of ammonia oxidation, were...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  2. Optimization on processing of low-temperature drying of chilled meat by uniform design method%均匀设计法优化冷鲜肉低温干燥工艺

    Institute of Scientific and Technical Information of China (English)

    赵惠麟; 周林

    2014-01-01

    The low-temperature food drying equipment was running at 0-10℃ to simulate the win-ter climate. The chilled meat with little salt and without food additives was dried. Through single factor ex-periment and uniform design method, the optimal processing technology was optimized. The quality differ-ences of product processed by low-temperature drying, natural drying and hot air drying was compared and analyzed. The result showed that the optimal low-temperature drying technology of chilled meat was 60% humidity, dried 72h at 5℃. The quality of product reached the best state with neat appearance, fresh color, cured flavor, smooth taste and modest hardness and the moisture content was 60. 2%. The product processed by low-temperature drying technology had significant advantages compared with natural drying and hot air drying.%利用低温食品干燥机在0~10℃运行,全年模拟冬季气候,用于低盐化无添加风干冷鲜肉,采用单因素实验法和均匀设计法优化了冷鲜肉低温干燥的最佳工艺,并对比分析了低温干燥与自然晾晒及热风干燥两种干燥方式的产品品质差异。结果表明:冷鲜肉的最佳低温干燥工艺为:5℃、60%湿度、干燥72h;产品外观整齐、色泽鲜嫩、腊味浓郁,含水率为60.2%,口感爽滑软硬适中,产品品质达到最佳状态;低温干燥与自然晾晒及热风干燥两种干燥方式相比,低温干燥产品品质优势明显。

  3. CO2 capture using aqueous ammonia: kinetic study and process simulation

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; van Well, Willy J.M.; Stenby, Erling Halfdan;

    2011-01-01

    to 0.6. The results were compared with those found for 30 wt% mono-ethanolamine (MEA) solutions.The capture process was simulated successfully using the simulator Aspen Plus coupled with the extended UNIQUAC thermodynamic model available for the NH3–CO2–H2O system. For this purpose, a user model...

  4. High efficient ammonia heat pump system for industrial process water using the ISEC concept. Part 2

    DEFF Research Database (Denmark)

    Olesen, Martin F.; Madsen, Claus; Olsen, Lars;

    2014-01-01

    The Isolated System Energy Charging (ISEC) concept allows for a high efficiency of a heat pump system for hot water production. The ISEC concept consists of two water storage tanks, one charged and one discharged. The charged tank is used for the industrial process, while the discharged tank...

  5. A pilot plant study for CO{sub 2} capture by aqueous ammonia applied to blast furnace gas in iron and steel making process

    Energy Technology Data Exchange (ETDEWEB)

    Young Kim, J.; Han, K.; Dong Chun, H. [CO2 Project, Research Inst. of Industrial Science and Technology, Pohang (Korea, Republic of)

    2009-07-01

    This presentation reported on a study in which carbon dioxide (CO{sub 2}) was captured from a demonstration iron and steel plant using low concentration aqueous ammonia as the absorbent chemical. The pilot plant was designed to process 50 Nm{sup 3}/h of blast furnace gas (BFG). The feed gas contained more than 20 per cent CO{sub 2} at 35 to 60 degrees C. Test runs revealed that the absorption efficiency of CO{sub 2} exceeded 80 per cent with a CO{sub 2} purity of more than 90 per cent in the product stream. The process parameters are currently being studied along with the various salts needed to prevent salt precipitation. It was determined that the use of waste heat recovery technology in the iron and steel-making process can render ammonia-based CO{sub 2} capture technology more economically feasible for the reduction of CO{sub 2}.

  6. Influence of mist-chilling on post-harvest quality of fresh strawberries Cv. Mara des Bois and Gariguette

    Energy Technology Data Exchange (ETDEWEB)

    Allais, Irene [Cemagref, UMR Genial, 24, avenue des Landais B.P. 50085, 63172 Aubiere Cedex (France); Letang, Guy [Cemagref, UMR Genial, Parc de Tourvoie, B.P. 44, 92163 Antony Cedex (France)

    2009-09-15

    The aim of this study was to assess the impact of mist-chilling on high-grade strawberry post-harvest quality (Cultivars ''Gariguette'' and ''Mara des Bois''). Strawberries were chilled at 2 C using three processes: air blast chilling at 0.3 m s{sup -1} or 1 m s{sup -1} and mist-chilling at 1 m s{sup -1}. After chilling, fruits were submitted to different distribution chains characterised by different handling conditions and storage temperatures (2 C or 7 C) and by a 12 h retailing step at 20 C. Strawberry quality was assessed by measuring 7 parameters: weight loss, commercial loss, firmness, sugar content, acidity, colour and sensory quality. Compared to air-chilling, mist-chilling did not reduce chilling time but it reduced weight loss by 20-40%. Mist-chilling had no detrimental effect on commercial loss defined as the percentage of fruit more than 1/3 of surface affected. It did not induce any major changes on strawberry quality. Temperature fluctuations undergone during cold storage and retailing had a detrimental effect on weight loss. The beneficial effect of packaging on weight loss was confirmed. (author)

  7. Liquid ammonia processing of hemp fiber and its dying performance%汉麻纤维的液氨整理及其染色性能

    Institute of Scientific and Technical Information of China (English)

    张华; 张建春

    2009-01-01

    为研究液氨处理对汉麻性能的影响,本文将预处理后的纤维浸入液氨中,对比液氨处理前后汉麻纤维染色性能和其它性能的变化.发现汉麻纤维的木质素和果胶的含量对其染色性能有影响,特别果胶的影响最为显著;麻纤维均存在染色困难的问题,但不同的麻纤维的染色性也不完全相同,苎麻纤维的染色性略好于汉麻纤维;液氨处理有利于提高麻纤维的染色性,但去氨方式的不同,对麻纤维的染色性能的提高程度也有所不同,水洗去氨要好于烘燥去氨;随着液氨处理时间的延长,汉麻纤维的回潮率不断升高,但当处理时间超过30min后,其回潮率又会有所降低,但仍高于未处理试样.%In order to investigate the infection of liquid ammonia processing, hemp fiber after pretreatment was dip into liquid ammonia and the contrast was -made. It was found that the content of lignin and pectin of hemp effect the performance of dying, especially the pectin. It's hard to dye for Hemp fiber. But the dying performance was different and ramie fiber is slightly better than that of hemp fiber. Liquid ammonia processing was favor to improve the dying performance. Different way of removing ammonia brought different effect on the dying performance of hemp fiber. Washing is better than drying to remove ammonia. With ammonia processing passing by, regain of hemp fiber raise continuously. But when the time of processing exceed 30min, the regain fall down, which was still higher than unsettled sample.

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

    Science.gov (United States)

    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

  9. Processes of ammonia air–surface exchange in a fertilized Zea mays canopy

    Directory of Open Access Journals (Sweden)

    E. Nemitz

    2013-02-01

    Full Text Available 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

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

    Directory of Open Access Journals (Sweden)

    E. Nemitz

    2012-06-01

    Full Text Available 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  12. 冷却肉微生物腐败与冷链系统%Chilled meat microbial spoilage and chill chain system

    Institute of Scientific and Technical Information of China (English)

    金鑫; 周光宏; 徐幸莲

    2012-01-01

    冷却肉极易发生微生物腐败,温度是最关键的影响因素。冷链系统持续的低温能抑制微生物的生长繁殖,预防冷却肉腐败。本文简述了微生物代谢活动对冷却肉腐败的影响,重点将冷链系统分为加工冷链、运输冷链、销售冷链和家庭保藏四部分,分别从概念及存在的问题等方面加以阐述,并展望了其未来有待提高完善的地方。%Chilled meat highly prone to microbial spoilage,temperature seems to be the most important factor that influences the spoilage.Sustained low-temperature of chill chain can inhibit microbial growth and prevent chilled meat spoilage.The effect of microbial metabolism on chilled meat spoilage was briefly introduced.Attention was drawn to the chill chain system which divided into four parts of processing, transportation, retail and domestic storage,and separately discussed the concept and issues of each part. The advance of chilled meat were prosoected as well.

  13. 氨氧化工艺(AMOXP)处理高氨氮有机废水%Ammonia oxidation process for the treatment of organic wastewater containing high-cncentration ammonia nitrogen

    Institute of Scientific and Technical Information of China (English)

    刘卫霞; 张科; 刘天宇; 李丽; 高照吉

    2015-01-01

    介绍了某生物工程厂采用厌氧工艺(循环式颗粒污泥反应器,即MQIC反应器)、氨氧化工艺和絮凝沉淀池处理厂区生产废水,处理量为10000 m3/d,该工艺系统对原水中COD、NH4+-N、TN的去除率分别可达97%、98%、90%,运行稳定,整个工艺处理出水水质可达到园区接管要求。同时,对厂区MQIC反应器和氨氧化工艺的启动调试进行了阐述,实践证明该工艺系统对处理高氨氮有机废水效果显著。%The plant-produced wastewater of a bioengineering plant has been treated by anaerobic process (circula-ting granula sludge reactor,i.e. MQIC reactor),ammonia oxidation process and flocculation-sedimentation tank, whose treatment capacity is 10 000 m3/d. The removing rates of COD,NH4+-N and TN are 97%,98% and 90%, respectively. The operation is stable and the effluent water quality could meet the acceptable requirements specified by the industrial park. In addition,the statement on the start-up and debugging for MQIC reactor and AMOXP are made. The practice proves that this process has remarkable effect on the treatment of organic wastewater containing highly concentrated ammonia nitrogen.

  14. Ammonia as efficient fuel for SOFC

    Energy Technology Data Exchange (ETDEWEB)

    Fuerte, A.; Valenzuela, R.X.; Escudero, M.J. [CIEMAT, Departamento de Energia, Av. Complutense 22, 28040 Madrid (Spain); Daza, L. [CIEMAT, Departamento de Energia, Av. Complutense 22, 28040 Madrid (Spain); Instituto de Catalisis y Petroleoquimica (CSIC), C/Marie Curie 2, Campus Cantoblanco, 28049 Madrid (Spain)

    2009-07-01

    Ammonia is a possible candidate as the fuel for SOFCs. In this work, the influence on the performance of a tubular SOFC running on ammonia is studied. Analysis of open circuit voltages (OCVs) on the cell indicated the oxidation of ammonia within a SOFC is a two-stage process: decomposition of the inlet ammonia into nitrogen and hydrogen, followed by oxidation of hydrogen to water. For comparison, cell was also tested with hydrogen as the fuel and air as oxidant at different temperatures showing a similar behaviour. The performance of the cell tested under various conditions shows the high potential of ammonia as fuel for SOFCs. (author)

  15. Archaeal ammonia oxidation in volcanic grassland soils of Iceland. Effects of elevated temperature and N availability on processes and organisms

    NARCIS (Netherlands)

    Daebeler, A.

    2014-01-01

    Thaumarchaea are recognized today as the most abundant and ubiquitously dis­tributed archaeal organisms, especially in the oceans and soil. Their phylogenetic placement as a phylum, the capability of all cultivated Thaumarchaea to oxidize ammonia for energy conservation as well as many further aspec

  16. 氨法制取纳米氧化锌的粒径控制研究%Particle size control of nano - sized zinc oxide by ammonia process

    Institute of Scientific and Technical Information of China (English)

    蔡建国; 蔡睿敏

    2009-01-01

    为有效控制氨法制取纳米氧化锌的粒径,在蒸氨前将浸出原液用一定量的纯净水稀释,可增加初期沉淀生成的晶核数,使沉淀粒径更加均匀和细化,同时发现蒸氨残液不可以作为浸出原液的稀释剂回用.蒸氨的加热方式对纳米氧化锌的粒径也有影响,选择蒸汽直接加热,当溶液含锌质量浓度小于0.3 g/L时,所制取的纳米氧化锌粒径满足GB/T 19589-2004纳米氧化锌的要求 .%In order to effectively control the particle size of nano - sized zinc oxide prepared by ammonia process,leaching stock solution was diluted with a certain amount of purified water before ammonia distillation process,which could increase the quantity of crystal nucleus generated by initial precipitation and make particle size of precipitate more uniform and refined.Meanwhile,it was found that distilled ammonia residual liquid could not be served as diluent of leaching stock solution for recycling.Also,heating method of ammonia distillation will affect the particle size of nano - sized zinc oxide.Particle size of prepared nano - sized zinc oxide can satisfy the requirements of GB/T 19589-2004,when direct steam heating was selected and mass concentration of zinc in the solution was less than 0.3 g/L.

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

    DEFF Research Database (Denmark)

    Móring, A; Vieno, M.; Doherty, R M;

    2015-01-01

    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...... 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 pH is necessary to reproduce the temporal...

  18. Study of Ammonia Emissions in a Ventilated Pig Pen

    OpenAIRE

    Rong, Li

    2011-01-01

    Pig productions cause a wide emission of odors, such as ammonia (NH3), hydrogen sulfide (H2S), and methane (CH4). Ammonia is one of the most important emissions for evaluating the air quality either in animal buildings or atmospheric environment. In studies of ammonia emission from animal buildings reported in literature, little effort has been made to investigate the accuracy of current Henry’s law constant for modeling ammonia mass transfer process and study ammonia emissions in a full scal...

  19. Chilling of carcasses from double muscled cattle: time-temperature evolution and predictive modelling of growth of Listeria monocytogenes and Clostridium perfringens

    OpenAIRE

    Delhalle, Laurent; Collignon, Bertrand; Dehard, Sandrine; Didimo Imazaki, Pedro Henrique; Daube, Georges; Clinquart, Antoine

    2010-01-01

    The time/temperature combination during carcass chilling is of concern in order to avoid bacterial growth. The chilling speed is lower in carcasses with high muscular development such as large cattle from the Belgian Blue breed. Three slaughterhouses were selected for temperature and pH measurements during the chilling process at 6 different days on 4 half carcasses in order to obtain representative data from heavy carcasses with high muscular development. Predictive microbiology was used to ...

  20. An innovative bioelectrochemical-anaerobic digestion-coupled system for in-situ ammonia recovery and biogas enhancement: process performance and microbial ecology

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    (SMRC) and a continuous stirred tank reactor (CSTR), to prevent ammonia toxicity during anaerobic digestion 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 with an average recovery rate of 0.18 g-N/L(CSTR...... performance was enhanced. In addition, the coexistence of other cations in CSTR or cathode had no negative effect on the ammonia transportation. In continuous reactor operation, 112% extra biogas production was achieved due to ammonia recovery. High-throughput molecular sequencing analysis showed an impact...... of ammonia recovery on the microbial community composition in the integrated system. Results clearly indicate the great potential of the SMRC-CSTR-coupled system for efficient and cost-effective ammonia recovery, energy production and treatment of ammonia-rich residues....

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  5. Ammonia effect on hydrogenotrophic methanogens and syntrophic acetate oxidizing bacteria

    DEFF Research Database (Denmark)

    Wang, Han; Fotidis, Ioannis; Angelidaki, Irini

    2015-01-01

    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...

  6. Studies of Radiation Mechanisms as Applied to the Potential Manufacturing Processes: Hydrazine from Ammonia, Nitrogen Fixation and Ozone from Oxygen

    International Nuclear Information System (INIS)

    The slow progress of the past decade toward industrial utilization of radiation in chemical manufacturing is related, among other things, to the tendency to oversimplify or ignore the basic mechanisms and the essential complexity of the radiation chemical systems. The importance of the fundamental approach is illustrated by the radiation systems of hydrazine from ammonia, nitrogen fixation, and ozone from oxygen. Since the First Geneva Conference on the ''Peaceful Uses of Atomic Energy'', radiation production of hydrazine has been of interest because of its high traditional cost and its potential large scale use for rocketry. While considerable efforts had been made on the engineering aspects of such a system, little attention was paid to its radiation chemistry. We have examined this system theoretically and experimentally and have identified the basic mechanism by which yields of hydrazine are limited. On the basis of this mechanism we have proposed a method to increase yields, which has been confirmed by experimental studies. Coincidence mass spectrometry shows a major ionization reaction over a wide energy range forming hydrogen radicals and amino ions, NH2+. Workers.studying the photolysis of ammonia have shown that hydrogen radicals destroy hydrazine. Under radiolysis conditions that allow krypton or xenon to absorb nearly all of the radiation energy, the subsequent charge exchange reactions are unable to form hydrogen atoms directly, since the recombination energy of xenon and krypton are such that direct H formation is strongly endothermic: under these conditions we find a significant increase in the yield of hydrazine. By contrast, the charge exchange of ammonia with neon ions to form hydrogen radicals and the amino ion is strongly exothermic: under these conditions we find a large decrease in the hydrazine yield. For nitrogen fixation by irradiation, there is insufficient experimental data to allow confidence in theoretical predictions. Mass spectrometer

  7. CFX Analysis of the Heat and Mass Transfer During the Chilling of a Lamb Carcass using a 3D Model

    OpenAIRE

    Hannon, Joseph; Keane, Garrett; O'Flaherty, Micheal

    2013-01-01

    Lamb meat is a popular red meat which must go through a complex refrigeration process before being served at the dinner table to reduce bacterial growth and retain meat quality. A major disadvantage of chilling is the drip losses which are losses in weight by evaporation of water contained within the meat. The aim of this work is to simulate the conventional chilling process of a lamb carcass using a three dimensional model.

  8. Study of the acceleration of ammonia generation process from poultry residues aiming at hydrogen production; Estudo do processo para a aceleracao da geracao de amonia a partir de residuos avicolas visando a producao de hidrogenio

    Energy Technology Data Exchange (ETDEWEB)

    Egute, Nayara dos Santos

    2010-07-01

    The hydrogen, utilized in fuel cells, can be produced from a variety of intermediate chemicals, between them, the ammonia. The ammonia gas as a raw material for the hydrogen production has been used due to its high energetic content, facility of decomposition, high availability, low prices, low storage pressure and its by-products are environmentally correct. One of the sources of ammonia is poultry and egg production systems. In these systems the ammonia is produced from the decomposition of uric acid present in the excreta of birds. The residue from the poultry-rearing farms is the broiler litter and from the egg production system is the excreta without any substrate. The characterization of these residues was performed using the Wavelength-Dispersive X-Ray Fluorescence (WDXRF), Elementary Analysis (CHN), Thermogravimetry and GC/MS - Gas chromatography/ Mass spectrometry. The studied factors which influence the ammonia volatilization were: nitrogen content, raising period, urease enzyme, temperature, pH and moisture content. The experiment results with poultry litter and excreta allow to conclude that the manipulation of the following parameters increased the ammonia emission: pH, nitrogen content, raising period, age of birds and excreta accumulation, urease enzyme and the temperature. The addition of different amounts of sand in the excreta and different volumes of water in the poultry litter inhibited the emission of ammonia. The variation of the quantity of material (broiler litter or excreta) and the volume of the flask used as incubator chamber showed no significant alterations to be chosen as a variable. The excreta was considered more appropriate than poultry litter for the objectives of this work due to the higher ammonia concentrations determined in this material. Due to the large amount of poultry litter and excreta from the production processes, the reuse of poultry residues to obtain ammonia is necessary to improve the quality of the local

  9. Study of the process for accelerating ammonia generation from poultry residues aiming its hydrogen production; Estudo do processo para a aceleracao da geracao de amonia a partir de residuos avicolas visando a producao de hidrogenio

    Energy Technology Data Exchange (ETDEWEB)

    Egute, Nayara dos Santos

    2010-07-01

    The hydrogen, utilized in fuel cells, can be produced from a variety of intermediate chemicals, between them, the ammonia. The ammonia gas as a raw material for the hydrogen production has been used due to its high energetic content, facility of decomposition, high availability, low prices, low storage pressure and its by-products are environmentally correct. One of the sources of ammonia is poultry and egg production systems. In these systems the ammonia is produced from the decomposition of uric acid present in the excreta of birds. The residue from the poultry-rearing farms is the broiler litter and from the egg production system is the excreta without any substrate. The characterization of these residues was performed using the wavelength-dispersive X-ray fluorescence (WDXRF), elementary analysis (CHN), thermogravimetry and GC/MS - gas chromatography/ mass spectrometry. The studied factors which influence the ammonia volatilization were: nitrogen content, raising period, urease enzyme, temperature, pH and moisture content. The experiment results with poultry litter and excreta allow to conclude that the manipulation of the following parameters increased the ammonia emission: pH, nitrogen content, raising period, age of birds and excreta accumulation, urease enzyme and the temperature. The addition of different amounts of sand in the excreta and different volumes of water in the poultry litter inhibited the emission of ammonia. The variation of the quantity of material (broiler litter or excreta) and the volume of the flask used as incubator chamber showed no significant alterations to be chosen as a variable. The excreta was considered more appropriate than poultry litter for the objectives of this work due to the higher ammonia concentrations determined in this material. Due to the large amount of poultry litter and excreta from the production processes, the reuse of poultry residues to obtain ammonia is necessary to improve the quality of the local

  10. Inhibiting Wet Oxidation of Ammonia

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  13. Cd{sub 1−x}Zn{sub x}S thin films with low Zn content obtained by an ammonia-free chemical bath deposition process

    Energy Technology Data Exchange (ETDEWEB)

    Carreón-Moncada, I. [Centro de Investigación y de Estudios Avanzados del IPN, Unidad Saltillo, Av. Industria Metalúrgica 1062, CP. 25900, Ramos Arizpe, Coah., México (Mexico); González, L.A., E-mail: luis.gonzalez@cinvestav.edu.mx [Centro de Investigación y de Estudios Avanzados del IPN, Unidad Saltillo, Av. Industria Metalúrgica 1062, CP. 25900, Ramos Arizpe, Coah., México (Mexico); Pech-Canul, M.I. [Centro de Investigación y de Estudios Avanzados del IPN, Unidad Saltillo, Av. Industria Metalúrgica 1062, CP. 25900, Ramos Arizpe, Coah., México (Mexico); Ramírez-Bon, R. [Centro de Investigación y de Estudios Avanzados del IPN, Unidad Querétaro, Apartado Postal 1-798, CP. 76001 Querétaro, Qro., México (Mexico)

    2013-12-02

    Cd{sub 1−x}Zn{sub x}S films with low Zn content were obtained on glass substrates by an ammonia-free chemical bath deposition process. Alkaline reaction solutions were prepared using cadmium chloride, zinc chloride, sodium citrate, thiourea and potassium hydroxide. As a result of varying the mixture ratio between Cd and Zn precursors, microstructural studies from X-ray diffraction reveal that the resulting films have hexagonal, wurzite type, crystalline structure with changes in the preferential growth orientation. Important changes on the surface morphology and thickness of the Cd{sub 1−x}Zn{sub x}S films were also observed as effects of adding Zn to the CdS lattice. Optical studies show that Cd{sub 1−x}Zn{sub x}S thin films with energy band gaps in the range from 2.48 to 2.65 eV were obtained. - Highlights: • Cd{sub 1−x}Zn{sub x}S layers were grown on glass by ammonia-free chemical bath deposition • Films with low Zn content were obtained using reaction solutions with pH11.5 • Zn addition produced changes on the orientation growth and morphology of the films • Cd{sub 1−x}Zn{sub x}S films have energy band gap values from 2.48 to 2.65 eV.

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

    CERN Document Server

    Hajigholi, 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

    [Abridged] Our aim is to explore the gas dynamics and the accretion process in the early phase of high-mass star formation. 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. 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 $J = 3\\leftarrow2$ 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...

  15. Ammonia emissions in Europe

    DEFF Research Database (Denmark)

    Jacobsen, Brian H.

    2012-01-01

    The NEC (National Emission Ceiling) directive has set targets for the 2010 ammonia emissions from a number of European countries. The target will be reached by most EU-countries and the total emission for EU-27 has been reduced by 22% from 1990 to 2007. Denmark is one of the countries...... technology is adopted quicker and that the farm has the right location. It is concluded that the new application process so far has not lived up to the high expectations at the outset. Despite this, the paper concludes that Denmark is likely to reduce emission by 50% from 1990 to 2020 and reach the likely...

  16. Ammonia Sensor Using Wavelength Modulation Spectroscopy

    KAUST Repository

    Farooq, Aamir

    2015-09-01

    An ammonia sensor can include a laser detector configured to provide stable sample readings. The sensor can implement a method including processing the recorded intensity of the laser beam to determine a first harmonic component and a second harmonic component and the amount of ammonia in the sample.

  17. Cylinder supplied ammonia scrubber testing in IDMS

    International Nuclear Information System (INIS)

    This report summarizes the results of the off-line testing the Integrated DWPF Melter System (IDMS) ammonia scrubbers using ammonia supplied from cylinders. Three additional tests with ammonia are planned to verify the data collected during off-line testing. Operation of the ammonia scrubber during IDMS SRAT and SME processing will be completed during the next IDMS run. The Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) scrubbers were successful in removing ammonia from the vapor stream to achieve ammonia vapor concentrations far below the 10 ppM vapor exit design basis. In most of the tests, the ammonia concentration in the vapor exit was lower than the detection limit of the analyzers so results are generally reported as <0.05 parts per million (ppM). During SRAT scrubber testing, the ammonia concentration was no higher than 2 ppM and during SME testing the ammonia concentration was no higher than 0.05 m

  18. 基于Aspen Plus的稀氨水吹脱工艺流程模拟%Simulation for Stripping Process flow of Dilute Ammonia Liquor Based on Aspen Plus

    Institute of Scientific and Technical Information of China (English)

    任苏孟; 陈洁; 宣爱国; 李志刚

    2014-01-01

    为了降低合成氨工艺中稀氨水的排放浓度,使用Aspen Plus 软件对氨水吹脱过程进行模拟计算,在满足塔底氨含量小于0.5%的要求下,得出吹脱塔适宜的操作参数:进料空气流量为500 kg/h,进料氨水温度为60℃,理论塔板为6块,选用50 mm钢制矩鞍环填料,塔径为1.4 m。%In order to decrease the concentration of diluted ammonia water emissions in synthetic ammonia process , the ammonia water stripping process was simulated based on Aspen Plus software.Under satisfying the condition that ammonia content in the tower bottom was less than 0.5%, the suitable operation parameters were obtained for the air stripping tower .The feeding temperature of ammonia water was 60℃, number of theoretical tower plates was 6, the feeding air flow was 500 kg/h, and the diameter of the stripping tower was 1.4 m with φ50 steel INTX packing selected.

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

    Science.gov (United States)

    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.

  20. Molecular Characterization of Soil Ammonia-Oxidizing Bacteria Based on the Genes Encoding Ammonia Monooxygenase

    OpenAIRE

    Alzerreca, Jose Javier

    1999-01-01

    Ammonia-oxidizing bacteria (AOB) are chemolithotrophs that oxidize ammonia/ammonium to nitrite in a two-step process to obtain energy for survival. AOB are difficult to isolate from the environment and iso lated strains may not represent the diversity in soil. A genetic database and molecular tools were developed based on the ammonia monooxygenase (AMO) encoding genes that can be used to assess the diversity of AOB that exist in soil and aquatic environments without the isolation of pure cult...

  1. Guns on Campus: A Chilling Effect

    Science.gov (United States)

    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…

  2. Chill unit accumulation and necessity of rest breaking agents in South African table grape production regions

    Directory of Open Access Journals (Sweden)

    Avenant Eunice

    2014-01-01

    Full Text Available Cultivation of table grapes in warm regions of South Africa is complicated by problems associated with delayed and uneven bud break. Rest breaking agents, mainly hydrogen cyanamide, are applied to overcome these problems. The chill unit accumulation of the five major table grape production regions in South Africa was compared with the minimum chilling required to obtain a high bud break percentage (>80% and even bud break, defined as 200 hours between 0 and 10 ∘C, or 400 hours at 3 ∘C. The effect of chilling accumulation (0, 50, 100, 200, 400 and 800 hours at 3 ∘C on bud break of dormant cuttings of three table grape cultivars was investigated in controlled studies in a glass house over a three year period. Cuttings used in the study were collected from commercial vineyards in Saron in the Berg River Valley (representing a warm region and the Hex River Valley (representing a cool region. Sultanina and Sugraone cuttings from Saron required at least 200 hours at 3 ∘C to obtain a final bud break % of 80%+. A final bud break % of 80%+ was obtained with all Sultanina cuttings from Hex River Valley. Treatments receiving 400 and 800 hours at 3 ∘C, showed the most rapid rate of bud break. Prime cuttings collected from Saron, receiving 0, 50, 100 and 400 hours at 3 ∘C, showed a more rapid bud break process, as well as a higher final bud break % compared to Sugraone and Sultanina. It seems as if Prime has a lower chilling requirement than the other two cultivars. The model of Dokoozlian for quantifying chilling status is applicable to Saron and the Hex River Valley. The necessity of using rest breaking chemicals in the Saron area, for obtaining a high bud break % and even bud break, was confirmed. The Hex River Valley receives sufficient chilling temperatures to obtain a high bud break %, but rest breaking chemicals can be used to obtain more even bud break. The use of hydrogen cyanamide for improved and even bud break is a general

  3. Modelling of ammonia emissions from dairy cow houses

    OpenAIRE

    Monteny, G.J.

    2000-01-01

    Dairy cow husbandry contributes to environmental acidification through the emission of ammonia. In-depth knowledge on the processes and variable factors that play a role in the emission of ammonia from dairy cow houses benefits the production of emission data, the development of low emission housing systems, and evaluation of emission levels in a farming system approach. A mechanistic simulation model for the ammonia emission from dairy cow houses was developed to facilitate this.An ammonia p...

  4. 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..

    Directory of Open Access Journals (Sweden)

    Gulshan Kumar

    Full Text Available 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

  5. 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.)

    Science.gov (United States)

    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

  6. 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.).

    Science.gov (United States)

    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

  7. Transcriptome Analysis of Pepper (Capsicum annuum Revealed a Role of 24-epibrassinolide in Response to Chilling

    Directory of Open Access Journals (Sweden)

    Li Jie

    2016-08-01

    Full Text Available 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

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

    Science.gov (United States)

    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

  9. [The use of "sous vide" technology in the packaging of chilled and ready to serve food].

    Science.gov (United States)

    Zalewski, S

    1999-01-01

    As chilled precooked dishes show limited to 3-5 days shelf life several additional factors have to be applied to extend it up to 21 or even 42 days as is sometimes allowed for sous vide technology products. Those factors comprise high hygienic standards for raw materials and premises as well as technological steps and parameters that efficiently destroy microbial contamination, and do not allow for recontamination or bacterial growth. Such steps include precooking which also means pasteurisation in high vacuum or anaerobic atmosphere in sealed pouches, blast chilling, low temperature storage parameters as well as high temperature of reheating process and quick serving procedures. Paper specifies parameters for each technological steps and presents microbiological requirements for final products. Sous vide technology allows for good quality and high nutritional value in soups, meats in sauces and stewed vegetables. It is used for individual consumer in chilled "ready to eat" line dishes in supermarkets and supplies such dishes for catering units. PMID:10523935

  10. Design and Optimization of the Shift Process in the Ammonia Production System%合成氨系统变换工艺的设计与优化

    Institute of Scientific and Technical Information of China (English)

    马如芬; 汪旭红; 魏焕景

    2012-01-01

    针对某合成氨系统粗煤气中CO含量高、水碳比低的特点,进行了CO变换工艺设计与优化.为达到设定的各段变换炉出口CO体积分数的设计指标,提出了两种补水(补汽)方案,并从平衡温距、甲烷化副反应及变换炉出口CO含量方面进行了对比,最终从工艺流程及补入蒸汽量方面进行了优化,确定了一个既经济合理又能达到预期指标的工艺方案.%The shift process is an important purification unit of an ammonia production system, and how to determine the right process becomes a key issue in the design. Based on the known characteristics of the gas components and the indications of the shift process, two different scenarios were made on the water and gas make -up and comparisons were also made on their equilibrium temperature intervals, side reactions of methanation and also the CO contents at the outlet of the converter. The process and the steam make-up quantity were optimized and finally a sound process program was determined which was both economical and practical.

  11. Comparison of Aeration Strategies for Optimization of Nitrogen Removal in an Adsorption/Bio-oxidation (A/B) Process with an Emphasis on Ammonia vs. NOx (AvN) control

    OpenAIRE

    Sadowski, Michael Stuart

    2015-01-01

    Research was performed at a pilot-scale wastewater treatment plant operating an adsorption/bio-oxidation (A/B) process at 20C. The study compared B-Stage performance under DO Control, Ammonia Based Aeration Control (ABAC), and Ammonia vs. NOx (AvN) control. AvN in 1) fully-intermittent and 2) intermittently-aerated MLE configurations was compared to DO Control and ABAC, each with continuous aeration, in an MLE configuration. The study also examined operation of each aeration strategy with two...

  12. Experimental evaluation of desuperheating and oil cooling process through liquid injection in two-staged ammonia refrigeration systems with screw compressors

    International Nuclear Information System (INIS)

    This paper examines the problem of achieving desuperheating through liquid injection in two-staged refrigeration systems based on screw compressors. The oil cooling process by refrigerant injection is also included. The basic thermodynamic principles of desuperheating and compressor cooling as well as short comparison with traditional method with a thermosyphon system have also been presented. Finally, the collected data referring to a big refrigeration plant are analyzed in the paper. Specific ammonia system concept applied in this refrigeration plant has demonstrated its advantages and disadvantages. - Highlights: ► An experiment was setup during a frozen food factory refrigeration system reconstruction and adaptation. ► Desuperheating and low-stage compressors oil cooling process were investigated. ► Efficiency of compression process and high-stage compressors functioning were examined. ► Evaporation temperature reduction has great influence on the need for injected liquid refrigerant. ► Several cases in which desuperheating and oil cooling process application are justified were determined.

  13. Texture evolution of continuous cast and direct chill cast AA 3003 aluminum alloys during cold rolling

    International Nuclear Information System (INIS)

    The texture evolution of continuous cast (CC) and direct chill cast (DC) AA 3003 aluminum alloys during cold rolling was investigated by X-ray diffraction. The relationship between texture volume fractions and rolling true strain was described quantitatively by mathematical formulae. The effect of processing method (CC vs. DC) on texture evolution was determined

  14. FORMATION OF WEAR-RESISTANT CHROMIUM CAST IRON CASTING INTO THE CHILL MOLD

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2013-01-01

    Full Text Available The analysis of thermal processes of formation of castings from wearproof chromic cast irons for replaceable details of centrifugal mills and crushers is carried out. Influence of protective and dividing coverings on intensity of heating of the chill mold is investigated.

  15. Rapid chilling cannot prevent inferior pork quality caused by high preslaughter stress

    NARCIS (Netherlands)

    Hambrecht, E.; Eissen, J.J.; Klein, W.J.H.; Ducro, B.J.; Smits, C.H.M.; Verstegen, M.W.A.; Hartog, den L.A.

    2004-01-01

    The present experiment investigated whether increasing chilling rate could improve meat quality in pigs exposed to either minimal or high stress immediately preslaughter. Pigs (n = 192) were offspring of halothane-free lines. On various days, four groups of 48 pigs were processed at a commercial pla

  16. Higher Chilling-Tolerance of Grafted-Cucumber Seedling Leaves upon Exposure to Chilling Stress

    Institute of Scientific and Technical Information of China (English)

    LI Jian-yong; TIAN Hai-xia; LI Xin-guo; MENG Jing-jing; HE Qi-wei

    2008-01-01

    The roots of figleaf gourd (Cucurbita ficifolia, as rootstock) could improve the resistance of cucumber plants (Cucumis sativus L. cv. Jinyan 4, as scion) to low temperature. In this experiment, the root activity and photosynthetic activity of photosystems in the own-rooted and grafted-cucumber plants were studied at chilling temperature (4℃) under low irradiance (100 μmol m-2 s-1 PFD). Compared with dark adaptation seedlings, the chlorophyll a fluorescence transient curve and the oxidizable P700 (P700+) of both the own-rooted and grafted seedlings decreased, and PS2 and PSl of the own-rooted seedling leaves were more inhibited than that of grafted ones at the end of chilling stress. The reduced triphenyltetrazolium chloride (TTC), which was used to reflect the root activity, kept stable in grafted seedling roots at the end of chilling stress, while it decreased noticeably in the own-rooted seedling roots. These results implied that the root system activity of the grafted seedling roots was higher than that of the own-rooted ones. Superoxide dismutase (SOD) activity was higher in both the grafted seedling roots and leaves than that in own-rooted seedlings at both room temperature and chilling temperature. Upon exposure to chilling stress, the malondialdehyde (MDA) content, which reflects the degree of lipid peroxidation, increased markedly in the own-rooted seedling roots and leaves and kept stable in the grafted-cucumber seedlings.

  17. Directional distribution of chilling winds in Estonia

    Science.gov (United States)

    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.

  18. Pretreatment of Biomass by Aqueous Ammonia for Bioethanol Production

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  20. Cook & Chill - Rapid Chilling of Food 'in situ'

    DEFF Research Database (Denmark)

    Paul, Joachim

    2003-01-01

    Rapid cooling of products is of increasing importance for food preservation and for industrial processes. Slurry ice (Binary Ice) is a two-phase cooling fluid consisting of suspended ice crystals in an aqueous solution or mixture. Latent energy contained in the fluid yields rapid cooling which...

  1. 氨合成系统开车初期避免设备结冰损坏的方式比较%Comparison of Equipment Freezing Damage Avoidance Processes during Initial Start ̄up of Ammonia Synthesis System

    Institute of Scientific and Technical Information of China (English)

    李雁

    2015-01-01

    Author has introduced 3 processes for avoiding equipment freezing damage during initial start ̄up of ammonia synthesis system, i. e. manu ̄al pressure control process, ammonia injection process and gas once passage. Expatiated upon the ammonia injection process principles and made analysis and comparison on these three processes from the viewpoint of process, and gave out preliminary recommendations for selection of start ̄up processes.%介绍了氨合成系统开车初期避免设备结冰损坏的3种主要方式,即手动控制压力流程、注氨流程和气体一次性通过流程。着重阐述了注氨流程的原理,并从工艺的角度对3种流程进行了分析和比较,对开车方式的选择给出了初步建议。

  2. Analisis Kecepatan Bottom Block Terhadap Struktur Mikro Produk Direct Chill Casting

    Directory of Open Access Journals (Sweden)

    Soejono Tjitro

    2004-01-01

    Full Text Available Direct chill casting process is used to produce to ingot. To produce to ingot is influenced such as bottom block speed. The objective of this research is to examine to ingot's microstructures. To use to bottom block speed is 57 mm/min and 67 mm/min. The pouring temperature of melt aluminum alloys is 750oC. Water flow rate is constant. Testing specimen is round shape which diameter and length each 70 mm and 400 mm. Microstructures on longitudinal and transversal round is investigated. Generally, microstructures of product of Direct Casting Process is non-uniform dendritic. Grain shape of 67 mm/minute bottom block rate is larger than 57 mm/minute bottom block rate. Abstract in Bahasa Indonesia : Proses Direct Chill Casting digunakan untuk menghasilkan ingot. Proses pembuatan ingot ini dipengaruhi antara lain kecepatan bottom block. Penelitian ini bertujuan untuk mengamati pengaruh kecepatan bottom block terhadap struktur mikro ingot. Kecepatan bottom block yang digunakan 57 mm/menit dan 67 mm/menit. Temperatur tuang paduan aluminium 750oC. Debit air konstan. Spesimen uji berbentuk round dengan diameter 70 mm dan panjang 400 mm. Struktur mikro yang diamati pada ke arah longitudinal dan transversal round. Struktur mikro yang dihasilkan proses direct chill casting secara umum adalah dendritik yang tidak seragam. Bentuk butir kecepatan bottom block 67 mm/menit lebih besar daripada kecepatan bottom block 57 mm/menit. Kata kunci: direct chill casting, struktur mikro, kecepatan bottom block.

  3. Catalyst for Ammonia Oxidation

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a bimetallic catalyst for ammonia oxidation, a method for producing a bimetallic catalyst for ammonia oxidation and a method for tuning the catalytic activity of a transition metal. By depositing an overlayer of less catalytic active metal onto a more catalytic...

  4. Assessing Ammonia Treatment Options

    Science.gov (United States)

    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...

  5. Method for forming ammonia

    Science.gov (United States)

    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.

  6. Vaporization reduction characteristics of aqueous ammonia solutions by the addition of ethylene glycol, glycerol and glycine to the CO2 absorption process

    Institute of Scientific and Technical Information of China (English)

    Jong-Beom Seo; Soo-Bin Jeon; Je-Young Kim; Gang-Woo Lee; Jong-Hyeon Jung; Kwang-Joong Oh

    2012-01-01

    Aqueous ammonia(NH3)solution can be used as an alternative absorption for the control of CO2 emitted from flue gases due to its high absorption capacity,fast absorption rate and low corrosion problem.The emission of CO2 from iron and steel plants requires much attention,as they are higher than those emitted from power plants at a single point source.In the present work,low concentration ammonia liquor,9 wt.%,was used with various additives to obtain the kinetic properties using the blast furnace gas model.Although a solution with a high ammonia concentration enables high CO2 absorption efficiency,ammonium ions are lost as ammonia vapor,resulting in reduced CO2 absorption due to the lower concentration of the ammonia absorbent.To decrease the vaporization of ammonia,ethylene glycol,glycerol and glycine,which contain more than one hydroxyl radical,were chosen.The experiments were conducted at 313 K similar to the CO2 absorption conditions for the blast furnace gas model.

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

    Science.gov (United States)

    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

  8. Ammonia transformation in a biotrickling air filter

    DEFF Research Database (Denmark)

    Nielsen, Lars Peter; Nielsen, Marie Louise; Andersen, Mathias;

    2007-01-01

    measurements and model was obtained by using conventional substrate and inhibition kinetics of ammonium and nitrite oxidizing bacteria. Highest rates of ammonia removal were observed in the central section of the filter. Near the air outlet and water inlet the process was ammonia limited, while high nitrous...... acid concentrations almost excluded any biological activity near the air inlet and water outlet. Nitrous acid inhibition also stabilized pH at 6.5-7 all through the filter. Being sensitive to both ammonia and nitrous acid the nitrite oxidation process occurred mainly in the filter sections near the air...... outlet / water inlet, and only 8% of the nitrite was turned into nitrate. Water supply only exceeded evaporation by 20% but modelling indicated that additional watering would have limited effect on filter efficiency. The filter was also robust to varying loading, as a 4-fold increase in ammonia inlet...

  9. Ultrafast dynamics of electrons in ammonia.

    Science.gov (United States)

    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

  10. Low-cost anodes for ammonia electrooxidation

    Science.gov (United States)

    Selverston, Steven M.

    This research focused on the development of low-cost electrodes for the electrochemical oxidation of ammonia to nitrogen, a reaction that has possible applications in hydrogen generation, direct ammonia fuel cells, water treatment, and sensors. Statistical design of experiments was used to help develop an efficient and scalable process for electrodeposition of platinum with a specific electrochemical surface area of over 25 m2 /g. Catalyst surface area and activity were evaluated using cyclic voltammetry, and the material microstructure and morphology were investigated using x-ray diffraction and scanning electron microscopy. The synthesized electrodes were found to be active toward the ammonia electrooxidation reaction, particularly when supporting electrolyte was added. However, supporting electrolyte was not required in order to oxidize the ammonia. As proof of concept, a homemade direct ammonia fuel cell employing a commercial anion exchange membrane was tested at room temperature with gravity-fed fuel and without supporting electrolyte. At room temperature, with passive reactant supply and using dissolved oxygen at the cathode, the cell produced about one quarter the power of a direct methanol fuel cell that used active transport of humidified oxygen and preheated (50 °C) methanol. With continued development of the membrane, cathode and membrane electrode assembly, the passive direct ammonia fuel cell using anion exchange membrane could have performance similar to the equivalent direct methanol fuel cell, and it could benefit from many advantages of ammonia over methanol such as lower cost, higher energy density, and reduced greenhouse gas emissions.

  11. WOOD COLOR CHANGES BY AMMONIA FUMING

    Directory of Open Access Journals (Sweden)

    Josip Miklečić,

    2012-06-01

    Full Text Available This paper studies the influence of ammonia gas on wood color changes in response to an increasing demand for dark colored wood specimens. The darker wood color in ammonia fuming is accomplished through chemical reactions between ammonia gas and wood compounds. We exposed oak, maple, spruce, and larch wood samples to ammonia gas for 16 days. During fuming, the color changes were studied using CIE L*a*b* parameters. After fuming, the changes in extractives content, tannin, and nitrogen content were analyzed. The chemical changes of wood and residues of wood extractives after fuming were analyzed by FTIR spectroscopy. Oak wood reacted intensively with ammonia gas in a very short time, and the darkening was prominent for all the investigated wood species. It was established that tannin had no major influence on color changes of maple and larch wood in the ammonia-fuming process. The FTIR spectra of fumed wood indicated involvement of carbonyl groups, and the FTIR spectra of wood extractives indicated involvement of carbonyl, aromatic, and alcohol groups in reaction with ammonia gas.

  12. Study of Ammonia Emissions in a Ventilated Pig Pen

    DEFF Research Database (Denmark)

    Rong, Li

    reported in literature, little effort has been made to investigate the accuracy of current Henry’s law constant for modeling ammonia mass transfer process and study ammonia emissions in a full scale pig pen from fluid dynamics by CFD simulations. This will be the main objectives of this study. The ammonia...... the accuracy of Henry’s law constants to determine the ammonia concentration in the air through the air-liquid interface. None of the present Henry’s law constant models provide a respectable agreement between simulated and measured results. A simplified model to determine the ammonia concentration in the air...... through the air-liquid interface is suggested from vapor-liquid equilibrium properties of ammonia water. Furthermore, the effects of airflow and temperature on ammonia mass transfer coefficient are also analyzed under different concentration boundary conditions determined by various Henry’s law constant...

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

    Science.gov (United States)

    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

  14. Ammonia synthesis at low temperatures

    DEFF Research Database (Denmark)

    Rod, Thomas Holm; Logadottir, Ashildur; Nørskov, Jens Kehlet

    2000-01-01

    have been carried out to evaluate its feasibility. The calculations suggest that it might be possible to catalytically produce ammonia from molecular nitrogen at low temperatures and pressures, in particular if energy is fed into the process electrochemically. (C) 2000 American Institute of Physics........ In contrast to the biological process, the industrial process requires high temperatures and pressures to proceed, and an explanation of this important difference is discussed. The possibility of a metal surface catalyzed process running at low temperatures and pressures is addressed, and DFT calculations...

  15. Comparative Proteomic Analysis of Rice at Filling Stage under Chilling Stress

    Institute of Scientific and Technical Information of China (English)

    Ying Wang; Weitong Cui; Shihua Shen

    2012-01-01

    Using comparative proteomic analysis,we carried out an investigation aiming at a better understanding of the molecular mechanisms of chilling stress adaptation in rice (O.sativa L.ssp.indica cultivar 93-11) at early filling stage.The rice plants at early filling stage were exposed to 12℃ for 6 h,12 h,24 h,48 h.Analysis of the dynamic proteome profile of the uppermost internodes showed that 99 protein spots were differentially expressed during this process.Among them,45 protein spots were found to be up-regulated and 54 protein spots were down-regulated in responding to chilling stress.81 protein spots were successfully identified through MALDITOF MS and database searching.Those identified proteins were the products of 65 genes,and could be sorted into 8 functional categories.Among them,secondary metabolism related proteins such as S-adenosylmethionine synthetase were up-regulated.That lignification-related proteins were up-regulated by chilling stress indicated the uppermost internodes supporting ear would be enhanced to resist the chilling stress.

  16. Corrosion of an aluminum alloy chilled in flowing seawater and the effect of cathodic prevention

    Energy Technology Data Exchange (ETDEWEB)

    Yabuki, A. [Graduate School of Engineering, Hiroshima University 1-4-1 Kagamiyama, Higashi-hiroshima, 739-8527 (Japan); Yasunaga, D.T. [Technical Development Group, Kobe Steel Ltd. 9-12, Kita-Shinagawa 5-chome, Shinagawa-ku, Tokyo, 141-0001 (Japan); Shibutani, T.; Shinkai, K. [Machinery and Engineering Company, Kobe Steel Ltd. 3-1, Shinhama 2-chome, Arai, Takasago, Hyogo 676-8670 (Japan)

    2007-05-15

    A new type of jet-in-slit testing apparatus for a specimen, chilled with a peltier element, was developed to investigate corrosion on the heat transfer surface of an aluminum alloy heat exchanger, in contact with a liquefaction gas at cryogenic temperature and in flowing seawater. The specimen can be chilled, even under flowing conditions, using this apparatus. Corrosion tests and polarization measurements of a specimen chilled by a peltier element were carried out in flowing seawater at various temperatures. The effect of chilling a specimen was equivalent to the effect achieved for a test in solution at a lower temperature. The process was dependent on a passive film, formed on the surface of the aluminum alloy specimen, as evidenced by polarization measurements. The extent of corrosion damage increased with increasing temperature of the solution, and showed maximum damage at high temperature. At high temperatures, erosion-corrosion was found at the central part of the specimen, but the effect of flow was negligible at low temperature. Corrosion tests for a cathodically polarized specimen were conducted under flowing conditions. Corrosion damage was accelerated by cathodic polarization at lower temperatures. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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. Ammonia transformations and abundance of ammonia oxidizers in a clay soil underlying a manure pond.

    Science.gov (United States)

    Sher, Yonatan; Baram, Shahar; Dahan, Ofer; Ronen, Zeev; Nejidat, Ali

    2012-07-01

    Unlined manure ponds are constructed on clay soil worldwide to manage farm waste. Seepage of ammonia-rich liquor into underlying soil layers contributes to groundwater contamination by nitrate. To identify the possible processes that lead to the production of nitrate from ammonia in this oxygen-limited environment, we studied the diversity and abundance of ammonia-transforming microorganisms under an unlined manure pond. The numbers of ammonia-oxidizing bacteria and anammox bacteria were most abundant in the top of the soil profile and decreased significantly with depth (0.5 m), correlating with soil pore-water ammonia concentrations and soil ammonia concentrations, respectively. On the other hand, the numbers of ammonia-oxidizing archaea were relatively constant throughout the soil profile (10(7) amoA copies per g(soil)). Nitrite-oxidizing bacteria were detected mainly in the top 0.2 m. The results suggest that nitrate accumulation in the vadose zone under the manure pond could be the result of complete aerobic nitrification (ammonia oxidation to nitrate) and could exist as a byproduct of anammox activity. While the majority of the nitrogen was removed within the 0.5-m soil section, possibly by combined anammox and heterotrophic denitrification, a fraction of the produced nitrate leached into the groundwater.

  19. Performance of a chill ATES system

    Energy Technology Data Exchange (ETDEWEB)

    Midkiff, K.C.; Song, Y.K.; Schaetzle, W.J. [Univ. of Alabama, Tuscaloosa, AL (United States)] [and others

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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. Preparation of soil nutrient amendment using white mud produced in ammonia-soda process and its environmental assessment

    Institute of Scientific and Technical Information of China (English)

    SHI Lin; LUO Han-jin

    2009-01-01

    A novel method to prepare soil nutrient amendment by calcining a mixture of white mud and potassium feldspar and its environmental assessment were investigated. Under the optimal conditions of a blending mass ratio of 70-30 for white mud to potassium feldspar, a calcination temperature of 1 000 ℃, a calcination time of 1.5 h and spherulitic diameter of 2.0 cm, the calcined product, as a soil nutrient amendment, could be prepared with the following nutrient composition (mass fraction): K2O 4.16%, CaO 23.43%, MgO 5.04%, SiO_2 22.92%, SO_4~(2-) 3.71%, and Cl- 3.87% in 0.1 mol/L citric acid solution. The concentrations of heavy metals in the calcined product and the emission concentrations of harmful gases from a mixture of white mud and potassium feldspar during calcination process could qualify the National Standards without causing secondary environmental pollution.

  3. 牛粪堆肥高温期氨氧化古菌与氨氧化细菌的多样性分析%Diversity of Ammonia-Oxidizing Bacteria and Ammonia-Oxidizing Archaea at High Temperature Phase during the Livestock Manure Composting Process

    Institute of Scientific and Technical Information of China (English)

    孙志远; 晏磊; 王彦杰; 林匡飞; 李辉; 王伟东

    2013-01-01

    The transmutation and loss of nitrogen materials were effected significantly by ammonia-oxidizing microorganisms during the composting process. In order to detect the diversity of Ammonia-Oxidizing Archaea (AOA)and Ammonia-Oxidizing Bacteria (AOB),the monooxygenase gene (amoA)was used to analyze as the tag at high-temperature phase during the livestock manure composting process. The results showed that Nitrosomonas genus and Nitrosospira genus were the dominant genus of AOB,and the amount of clones accounted for 59.3% and 40.7% among the clone library at the high-temperature period,respectively,and the amount of Nitrosomonas was more dominant than that of the Nitrosospira. For communities of AOA,the amount of AOA resulting from soil were greatly more than that of AOA resulting from sea. The ratio of clones of soil AOA was 94.2%,but the ratio of sea AOA accounted for only 5.8%among all of AOA clones.%堆肥化过程中,氨氧化微生物对堆肥原料的氮素转化和氮损失影响重大。为了分析牛粪堆肥高温期微生物的多样性,研究以氨单加氧酶基因(amoA)为标记,分析了牛粪堆肥高温阶段氨氧化古菌(Ammonia-Oxidizing Archaea,AOA)和氨氧化细菌(Ammonia-Oxidizing Bacteria,AOB)菌群多样性。结果表明,在AOB类群中,亚硝化单胞菌属(Nitrosomonas)和亚硝化螺菌属(Nitrosospira)克隆子数量分别占整个克隆文库的59.3%和40.7%,它们是堆肥高温期的优势氨氧化细菌,但是Nitrosomonas的数量比Nitrosospira更占优势。在AOA群落中,soil/sediment菌群占据绝对数量优势,其克隆子数量占AOA文库的94.2%,sea/sediment菌群仅占5.8%。

  4. Experimental characterization of the rectification process in ammonia-water absorption systems with a large-specific-area corrugated sheet structured packing

    Energy Technology Data Exchange (ETDEWEB)

    Sieres, Jaime; Fernandez-Seara, Jose; Uhia, Francisco J. [Area de Maquinas y Motores Termicos, E.T.S. de Ingenieros Industriales, Campus Lagoas-Marcosende No 9, 36310 Vigo, Pontevedra (Spain)

    2009-09-15

    In this paper, the mass transfer performance of a large-specific-area corrugated sheet structured packing for ammonia-water absorption refrigeration systems (AARS) is reported. An experimental facility was used to test the performance of the packing. Experimental results of the temperature, ammonia concentration and mass flow rate of the rectified vapour are presented and discussed for different operating conditions including reflux ratio values from 0.2 to 1. The volumetric vapour phase mass transfer coefficient is calculated from the measured data and compared with different correlations found in the literature. A new correlation is proposed which was fitted from the experimental data. Finally, a comparison is made between the actual packing height used in the experimental setup and the height required to obtain the same ammonia rectification in AARS with different packings previously tested by the authors. (author)

  5. Mechanism of silicon influence on the chill of cast iron

    Directory of Open Access Journals (Sweden)

    E. Fraś

    2007-12-01

    Full Text Available In this work an analytical solution of general validity is used to explain mechanism of the silicon influence on the absolute chill tendency (CT and chill (w of cast iron. It is found that CT can be related to nucleation potential of graphite (Nv, growth parameter (μ of eutectic cells, temperature range (ΔTsc and the pre-eutectic austenite volume fraction (fγ. It has been shown that silicon additions: a impede the growth of graphite eutectic cells, μ, b expands the temperature range ΔTsc, c increases the nucleation potential of graphite Nv, d lowers the pre-eutectic austenite volume fraction, fγ. and in consequence the absolute chilling tendency, CT decreases. The minimum wall thicknesses for chilled castings, or chill widths (w in wedge shaped castings is related to CT and as silcon contents increases, the w value also increases.

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

    Science.gov (United States)

    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

  7. Reactor for removing ammonia

    Science.gov (United States)

    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.

  8. Ammonia Clouds on Jupiter

    Science.gov (United States)

    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.

  9. Comparative evaluation of gum arabic coating and vacuum packaging on chilled storage characteristics of Indian mackerel (Rastrelliger kanagurta).

    Science.gov (United States)

    Binsi, P K; Nayak, Natasha; Sarkar, P C; Sahu, Upali; Ninan, George; Ravishankar, C N

    2016-04-01

    The effect of edible coating using gum arabic on biochemical, microbiological, textural and sensory characteristics of fresh gutted mackerel stored at 4 °C was investigated. The results were further compared against the samples packed under vacuum (VP) and conventional polyethylene pouches (CP). Coating with gum arabic (GC) markedly retarded lipid oxidation process in gutted mackerel compared to VP and CP samples. Moreover, VP and CP samples showed higher degree of textural deterioration compared to GC samples. Microbiologically, the shelf life of chilled gutted Indian mackerel was estimated to be 7-8, 17 and 19-20 days for CP, GC and VP samples, respectively. The sensory analysis scores confirmed the efficacy of gum coating in retarding the spoilage process during chilled storage. The current study identifies the potential of edible coating with gum arabic to improve the overall quality of Indian mackerel and extend its storage life during chilled storage. PMID:27413215

  10. Discussing Typical Process and Layout Scheme for Large/Middle-sized Coal-Made Synthetic Ammonia Plant%大中型煤制合成氨装置典型工艺与布置方案探讨

    Institute of Scientific and Technical Information of China (English)

    张占一; 孟强; 邹隐文

    2012-01-01

    Author has described the typical process technology and layout scheme in plant of the large/middle-sized synthetic ammonia made by feed- stock of coal; has discussed the problems to be possibly encountered in the design progress of the synthetic ammonia plant and its related matters to be no- ticed ; in combination with example of the Vietnam North Nitrogen Project, has summarized the principles and gist in the respects of process selection and equipment layout in the large/middle-sized synthetic ammonia plant.%阐述了大中型煤制合成氨装置的典型工艺技术和装置布置方案;探讨了合成氨装置设计过程中可能遇到的问题和相关注意事项;结合越南河北氮肥工程实例,总结了大中型合成氨装置在工艺选择和设备布置方面的原则和要领。

  11. Effect of modification melt treatment on casting/chill interfacial heat transfer and electrical conductivity of Al-13% Si alloy

    Energy Technology Data Exchange (ETDEWEB)

    Narayan Prabhu, K.; Ravishankar, B.N

    2003-11-15

    For successful modelling of the solidification process, a reliable heat transfer boundary condition data is required. These boundary conditions are significantly influenced by the casting and mould parameters. In the present work, the effect of sodium modification melt treatment on casting/chill interfacial heat transfer during upward solidification of an Al-13% Si alloy against metallic chills is investigated using thermal analysis and inverse modelling techniques. In the presence of chills, modification melt treatment resulted in an increase in the cooling rate of the solidifying casting near the casting/chill interfacial region. The corresponding interfacial heat flux transients and electrical conductivities are also found to be higher. This is attributed to (i) improvement in the casting/chill interfacial thermal contact condition brought about by the decrease in the surface tension of the liquid metal on addition of sodium and (ii) increase in the electronic heat conduction in the initial solidified shell due to change in the morphology of silicon from a acicular type to a fine fibrous structure and increase in the ratio of the modification rating to the secondary dendrite arm spacing.

  12. 含氨放射性废水吹脱法除氨研究%Treatment of Reactive Process Wastewater With High-Level Ammonia by Blow-off Method

    Institute of Scientific and Technical Information of China (English)

    陈晓彤; 权英; 王阳; 付亘娜; 刘兵; 唐亚平

    2012-01-01

    采用吹脱除氨工艺,对高温气冷堆燃料元件二氧化铀核芯颗粒生产中产生的含氨工艺放射性废液进行了除氨处理研究.分析了废水pH、加碱量、加热和吹脱时间等因素对吹脱除氨效果的影响,于80℃、吹脱3h后,废液的除氨效率可超过95%.对除氨后的废液体系进行了阴离子交换树脂吸附铀的静态实验,结果表明,树脂对铀吸附容量较未除氨时有明显提高.%The ceramic UO2 kernels for nuclear fuel elements of high temperature gas cooled reactors were prepared through sol-gel process with uranyl nitrate, which produces process wastewater containing high-level ammonia and uranium. The blow-off method on a bench scale was investigated to remove ammonia from reactive wastewater. Under the optimized operating conditions, the ammonia can be removed by more than 95%, with little reactive uranium distilled. The effects of pH, heating temperature and stripping time were studied. Static tests with ion-exchange resin indicate that ammonia removal treatment increases uranium accumulation in anion exchange resin.

  13. Use of gamma irradiation for improving the hygienic quality of chilled chicken

    International Nuclear Information System (INIS)

    Fresh, chilled chicken carcasses were irradiated at 2.5 kGy and stored at 40 degree C. At intervals samples were withdrawn for microbial, chemical and sensory evaluation. Result showed that combination of a 2.5 kGy irradiation dose and storage at 4 degree C were adequate for a radicidised chicken process. Immediately after irradiation, the microbial spoilage was reduced by at least 4 log cycles. The carcasses were qf excellent quality for at least 16 days of storage and were free from Salmonella and other food pathogens. Changes in chemical composition (moisture, fat, protein, ash and amino acids) and sensory quality of chicken carcasses irradiated at 2.5 kGy were not significant. Therefore the dose of 2.5 kGy should be the target for chilled chicken irradiation process

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

    Science.gov (United States)

    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.

  15. Why do insects enter chill coma? Low temperature and high extracellular potassium compromises muscle function in Locusta migratoria

    DEFF Research Database (Denmark)

    Findsen, Anders; Pedersen, Thomas Holm; Nielsen, Ole Bækgaard;

    -depressing effects that occur secondary to loss of ion-homeostasis. Using isolated tibial muscle of the chill susceptible locust we investigated the relationship between tetanic force production, temperature and extracellular [K+]. Tetanic force was elicited every 10 minutes using 2s trains of 1ms 12-V pulses...... temperature was reduced from 23°C to 0.5°C. Similarly, elevation of extracellular [K+] from a control value of 10 mM to 30 mM also caused a 50 % reduction of force. When muscles were simultaneously cooled and exposed to elevated K+, force was reduced to around 1 % of the control. These results suggest......Many insect species enter a comatose state when their body temperature is lowered to a critical limit (critical thermal minimum) but the physiological and cellular processes that underlie chill coma are still unresolved. Several studies have demonstrated that transition into chill-coma involves...

  16. Survival of Listeria monocytogenes, Listeria innocua, and Lactic acid bacteria species in chill brine

    OpenAIRE

    Meadows, Bridget Archibald

    2004-01-01

    SURVIVAL OF LISTERIA MONOCYTOGENES, LISTERIA INNOCUA, AND LACTIC ACID BACTERIA SPECIES IN CHILL BRINES Bridget Archibald Meadows (ABSTRACT) Listeria monocytogenes is the major pathogen in ready-to-eat meat products such as deli meats and frankfurters. Contamination can occur via the salt brines that are used to cool thermally processed meats. Both L. monocytogenes and lactic acid bacteria can grow and thrive under these brine conditions, and may become competitive with each ot...

  17. Sensory quality control in the chilled and frozen ready meal, soup and sauce sectors

    OpenAIRE

    Swainson, Mark; McWatt, Linda

    2010-01-01

    This chapter discusses the use of sensory evaluation in the assurance of product quality within the food production sectors of ready meals, soups and sauces. The chapter methodically reviews typical food processing stages, from recipe development through to end product supply, and considers how sensory assessment methods can be utilised to help assure the quality of the end products within these selected High Risk Chilled Food sectors.

  18. Oxydesulfurization of a Turkish hard lignite with ammonia solutions

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ. (Turkey). Chemical and Metallurgical Engineering Faculty

    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.

  19. Reseptioptimointi cook and chill -tuotantotapaan : Case: Kolarin keskuskeittiö

    OpenAIRE

    Pääkkölä, Henna

    2010-01-01

    Opinnäytetyön tarkoituksena oli perehtyä cook and chill -tuotantotapaan ja tutkia sen vaikutuksia reseptioptimointiin. Tavoitteena oli selvittää cook and chill -tuotantotavan etuja ja mahdollisia haasteita ammattikeittiön ruokatuotannossa sekä tuottaa aiheesta tietoa suomenkielisiä lukijoita varten. Opinnäytetyön tavoitteena oli myös optimoida Kolarin keskuskeittiön lounasruokalistan lämpimille aterioille cook and chill -tuotantotapaan soveltuvat ruokaohjeet sekä valmistusprosessikuvaukset. T...

  20. Manufacture of a Polyaniline Nanofiber Ammonia Sensor Integrated with a Readout Circuit Using the CMOS-MEMS Technique

    Science.gov (United States)

    Liu, Mao-Chen; Dai, Ching-Liang; Chan, Chih-Hua; Wu, Chyan-Chyi

    2009-01-01

    This study presents the fabrication of a polyaniline nanofiber ammonia sensor integrated with a readout circuit on a chip using the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process and a post-process. The micro ammonia sensor consists of a sensing resistor and an ammonia sensing film. Polyaniline prepared by a chemical polymerization method was adopted as the ammonia sensing film. The fabrication of the ammonia sensor needs a post-process to etch the sacrificial layers and to expose the sensing resistor, and then the ammonia sensing film is coated on the sensing resistor. The ammonia sensor, which is of resistive type, changes its resistance when the sensing film adsorbs or desorbs ammonia gas. A readout circuit is employed to convert the resistance of the ammonia sensor into the voltage output. Experimental results show that the sensitivity of the ammonia sensor is about 0.88 mV/ppm at room temperature. PMID:22399944

  1. Manufacture of a Polyaniline Nanofiber Ammonia Sensor Integrated with a Readout Circuit Using the CMOS-MEMS Technique

    Directory of Open Access Journals (Sweden)

    Chyan-Chyi Wu

    2009-02-01

    Full Text Available This study presents the fabrication of a polyaniline nanofiber ammonia sensor integrated with a readout circuit on a chip using the commercial 0.35 mm complementary metal oxide semiconductor (CMOS process and a post-process. The micro ammonia sensor consists of a sensing resistor and an ammonia sensing film. Polyaniline prepared by a chemical polymerization method was adopted as the ammonia sensing film. The fabrication of the ammonia sensor needs a post-process to etch the sacrificial layers and to expose the sensing resistor, and then the ammonia sensing film is coated on the sensing resistor. The ammonia sensor, which is of resistive type, changes its resistance when the sensing film adsorbs or desorbs ammonia gas. A readout circuit is employed to convert the resistance of the ammonia sensor into the voltage output. Experimental results show that the sensitivity of the ammonia sensor is about 0.88 mV/ppm at room temperature

  2. Industrialization of New Process to Electrolysis Zinc from Zinc Chloride and Ammonia Complex%氯化锌氨络合物制锌新工艺的工业化实践

    Institute of Scientific and Technical Information of China (English)

    邓良勋; 吴保庆

    2011-01-01

    用氯化铵与含氧化锌原料反应生成氯化锌氨络合物,净化后电解制取阴极锌.介绍了该流程的原理及工业试生产的有关情况.%The zinc chloride and ammonia complex was produced by reacting ammonium chloride with zinc oxide containing raw materials, after purification which was used to produce cathode zinc via electrolysis process.The principles of this process and industrialization pilot production were introduced in detail.

  3. Ammonia regeneration for a combined lime/ammonia spray dryer for SO[sub 2] control

    Energy Technology Data Exchange (ETDEWEB)

    Xinjian, Yang (Cincinnati Univ., OH (United States). Dept. of Civil and Environmental Engineering)

    1992-12-23

    A research project designed to study the feasibility of ammonia regeneration for a combined lime/ammonia FGD process was conducted at the University of Cincinnati. The major objective for this project was to regenerate ammonia from a combined ammonia/calcium hydroxide spray dryer FGD byproduct for reuse which would reduce the operating cost of this FGD process. This final report covers the six phases of the project: (1) generation of original feedstock, (2) batch regeneration studies, (3) continuous regeneration studies, (4) waste characteristic analysis, (5) pilot scale demonstration and (6) economic analysis. This research has shown that regeneration of ammonia is feasible at a reasonable cost. The effects on Ohio coal use from the results of this research could be substantial, depending on the Phase II application of FGD systems for controlling SO[sub 2] emissions. In conclusion, experiments in this study have shown that ammonia recovery efficiencies greater than 90% are technically and economically feasible. In addition, the sludge produced from the regeneration process is stable and will meet existing Federal standards.

  4. Transformation of ammonia i biological airfilters

    DEFF Research Database (Denmark)

    Nielsen, Lars Peter; Sørensen, Karen; Andersen, Mathias;

    2007-01-01

    Ammonia is a major compound in ventilation air from animal houses. In biological filters it is with varying efficiency transformed by physical, biological, and chemical processes and ends up as ammonium, nitrate, and nitrite dissolved in water and as dinitrogen, nitrous oxide and nitric oxide emi...... removal without too much energy consumption, waste water production, green house gas emission, or suppression of the filters odor removal efficiency.......Ammonia is a major compound in ventilation air from animal houses. In biological filters it is with varying efficiency transformed by physical, biological, and chemical processes and ends up as ammonium, nitrate, and nitrite dissolved in water and as dinitrogen, nitrous oxide and nitric oxide...

  5. Human perception of indoor environment generated by chilled ceiling combined with mixing ventilation or localised chilled beam under cooling mode

    DEFF Research Database (Denmark)

    Bolashikov, Zhecho Dimitrov; Nygaard, Linette; Uth, Simon C.;

    2014-01-01

    Experiments with 24 subjects were performed to study and compare the human perception of the indoor environment under summer conditions generated by a chilled ceiling combined with overhead mixing ventilation and localised chilled beam. The experiments were performed in an experimental chamber (4....../s during the 20 min period of physical activity, when the occupant was not at the desk with the localised chilled beam, resulting in increase of the air temperature in the room. Subjects used questionnaires to answer on thermal sensation and acceptability, perceived air quality, air movement and SBS...

  6. Respiratory ammonia output and blood ammonia concentration during incremental exercise

    NARCIS (Netherlands)

    Ament, W; Huizenga, [No Value; Kort, E; van der Mark, TW; Grevink, RG; Verkerke, GJ

    1999-01-01

    The aim of this study was to investigate whether the increase of ammonia concentration and lactate concentration in blood was accompanied by an increased expiration of ammonia during graded exercise. Eleven healthy subjects performed an incremental cycle ergometer test. Blood ammonia, blood lactate

  7. Enrichment of high ammonia tolerant methanogenic culture

    DEFF Research Database (Denmark)

    Fotidis, Ioannis; Karakashev, Dimitar Borisov; Proietti, Nicolas;

    of the current study was to isolate and identify methanogenic cultures tolerant to high ammonia concentrations. A mixed methanogenic population was stepwise exposed to ammonia concentrations (1 to 9.26 g NH4+-N L-1) during an enrichment process with successive batch cultivations. The methanogenic population...... was derived from a full scale biogas reactor (Hashøj, Denmark), fed with 75% animal manure and 25% food industries organic waste. Basal anaerobic medium was used for the enrichment along with sodium acetate (1 g HAc L-1) as a carbon source. Fluorescence insitu hybridization (FISH) was used to determine...... microbial community composition. The outcome of the enrichment process was a mesophilic aceticlastic methanogenic enriched culture able to withstand high ammonia loads and utilize acetate and form methane stoichiometrically. FISH analysis showed that the methanogens of the enriched culture belonged...

  8. 氨—碳铵法浸出含锌烟灰%Leaching of Zinc-bearing Ash with Ammonia-ammonium Bicarbonate Process

    Institute of Scientific and Technical Information of China (English)

    陈启元; 王树宾; 胡慧萍; 王为振

    2012-01-01

    研究氨—碳铵体系中pH、总氨浓度、液固比(L/S)、反应温度、反应时间等因素对三种含锌烟灰中锌和主要杂质元素浸出行为的影响.结果表明,较佳的工艺条件是:浸出剂总氨浓度9 mol/L、pH=10.00、L/S=5、反应温度50℃、反应时间60 min.此时锌浸出率大于80%.%The effects of pH, total ammonia concentration of ammonia-ammonium bicarbonate system, ratio of solid to liquid (L/S) , temperature and leaching time on the leaching behavior of zinc and main impurities in three kinds of zinc-bearing ash were investigated. The results show that the zinc leaching rate is over 80% under the optimum conditions including total ammonia concentration of 9 mol/L and pH of 10.00, L/S of 5, temperature of 50 ℃ , and the leaching time of 60 min.

  9. Liberation of ammonia by cyanobacteria

    International Nuclear Information System (INIS)

    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 14C 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

  10. Ammonia tolerant enriched methanogenic cultures as bioaugmentation inocula to alleviate ammonia inhibition in continuous anaerobic reactors

    DEFF Research Database (Denmark)

    Fotidis, Ioannis; Wang, Han; Angelidaki, Irini

    tolerant methanogenic culture as potential bioaugmentation inoculum in a continuous stirred tank reactor (CSTR) operating under “inhibited steady-state”, triggered by high ammonia levels (5 g NH4+-N L-1). The results of the current study established for the first time that bioaugmentation of an enriched...... ammonia tolerant methanogen in a CSTR reactor could completely alleviate the ammonia inhibitory effect. Furthermore, it was found that bioaugmentation with the enriched culture resulted in 25% higher methane production compared to when the bioaugmentation was achieved with pure methanogenic strains....... The bioaugmentation was performed without pausing the continuous operation of the CSTR reactor and without excluding the ammonia-rich substrate from the feedstock. Thus, bioaugmentation with mixed methanogenic cultures could potentially support the development of an efficient and cost-effective biomethanation process...

  11. Treatment of nickel-ammonia complex ion-containing ammonia nitrogen wastewater

    Institute of Scientific and Technical Information of China (English)

    MIN Xiao-bo; ZHOU Min; CHAI Li-yuan; WANG Yun-yan; SHU Yu-de

    2009-01-01

    Air stripping was adopted to treat nickel ammonia complex ion-containing wastewater in order to remove nickel and ammonia simultaneously in one technological process. The relationship among pH, the concentration of nickel ammonia complex ion and total ammonia concentration was analyzed theoretically. Influence of pH value, water temperature, airflow rate and time on air stripping was studied in detail by static experiment in laboratory. The results show that at pH 11, temperature of 60 ℃ and airflow rate of 0.12 m~3/h, NH_3 and Ni~(2+) concentrations remained in wastewater are less than 2 and 0.2 mg/L, respectively, after blowing for 75 min, which reaches the standard of the state discharge. When the tail gas is absorbed by 0.5 mol/L H_2SO_4 in order to avoid the secondary pollution, the absorption rate can achieve 70%.

  12. CHANGES OF BACKSCATTERING PARAMETERS DURING CHILLING INJURY IN BANANAS

    Directory of Open Access Journals (Sweden)

    NORHASHILA HASHIM

    2014-06-01

    Full Text Available The change in backscattering parameters during the appearance of chilling injury in bananas was investigated. Bananas were stored at a chilling temperature for two days and the degrees of the chilling injuries that appeared were measured before, during and after storage using backscattering imaging and visual assessment. Laser lights at 660 nm and 785 nm wavelengths were shot consecutively onto the samples in a dark room and a camera was used to capture the backscattered lights that appeared on the samples. The captured images were analysed and the changes of intensity against pixel count were plotted into graphs. The plotted graph provides useful information of backscattering parameters such as inflection point (IP, slope after inflection point (SA, and full width at half maximum (FWHM and saturation radius (RSAT. Results of statistical analysis indicated that there were significant changes of these backscattering parameters as chilling injury developed.

  13. Modelling of ammonia emissions from dairy cow houses

    NARCIS (Netherlands)

    Monteny, G.J.

    2000-01-01

    Dairy cow husbandry contributes to environmental acidification through the emission of ammonia. In-depth knowledge on the processes and variable factors that play a role in the emission of ammonia from dairy cow houses benefits the production of emission data, the development of low emission housing

  14. Dissociation and Mass Transfer Coefficients for Ammonia Volatilization Models

    Science.gov (United States)

    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...

  15. Ammonia effect on hydrogenotrophic methanogens and syntrophic acetate oxidizing bacteria

    DEFF Research Database (Denmark)

    Wang, Han; Fotidis, Ioannis; Angelidaki, Irini

    Substrates that contain high ammonia levels can cause inhibition on anaerobic digestion process and unstable biogas production. The aim of the current study was to assess the effects of different ammonia levels on pure strains of (syntrophic acetate oxidizing) SAO bacteria and hydrogenotrophic...

  16. 废水中氨氮的处理工艺技术方法探讨%Discussion on Ammonia-nitrogen-containing Wastewater Removal Process Technologics and Methods

    Institute of Scientific and Technical Information of China (English)

    王界智

    2012-01-01

    Several main ammonia-nitrogen removal technical processes were introduced in the paper.Biological treatment methods including UASB,A/O membrane bioreactor,IMO-SBR were summarized.Meanwhile electrochemical oxidation method and membrane treatment technology were also discussed in the paper.%文中对目前常用的几种废水脱氮技术方法进行了简单介绍,其中包括生物法的UASB工艺、A/O膜生物反应器法、IMO-SBR生物组合工艺,电化学氧化法及膜处理技术。

  17. An early response regulatory cluster induced by low temperature and hydrogen peroxide in seedlings of chilling-tolerant japonica rice

    Directory of Open Access Journals (Sweden)

    Jia Yulin

    2007-06-01

    Full Text Available Abstract Background Plants respond to low temperature through an intricately coordinated transcriptional network. The CBF/DREB-regulated network of genes has been shown to play a prominent role in freeze-tolerance of Arabidopsis through the process of cold acclimation (CA. Recent evidence also showed that the CBF/DREB regulon is not unique to CA but evolutionarily conserved between chilling-insensitive (temperate and chilling-sensitive (warm-season plants. In this study, the wide contrast in chilling sensitivity between indica and japonica rice was used as model to identify other regulatory clusters by integrative analysis of promoter architecture (ab initio and gene expression profiles. Results Transcriptome analysis in chilling tolerant japonica rice identified a subset of 121 'early response' genes that were upregulated during the initial 24 hours at 10°C. Among this group were four transcription factors including ROS-bZIP1 and another larger sub-group with a common feature of having as1/ocs-like elements in their promoters. Cold-induction of ROS-bZIP1 preceded the induction of as1/ocs-like element-containing genes and they were also induced by exogenous H2O2 at ambient temperature. Coordinated expression patterns and similar promoter architectures among the 'early response' genes suggest that they belong to a potential regulon (ROS-bZIP – as1/ocs regulatory module that responds to elevated levels of ROS during chilling stress. Cultivar-specific expression signatures of the candidate genes indicate a positive correlation between the activity of the putative regulon and genotypic variation in chilling tolerance. Conclusion A hypothetical model of an ROS-mediated regulon (ROS-bZIP – as1/ocs triggered by chilling stress was assembled in rice. Based on the current results, it appears that this regulon is independent of ABA and CBF/DREB, and that its activation has an important contribution in configuring the rapid responses of rice seedlings

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

    Science.gov (United States)

    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

  19. [Visible/NIR analysis of fat, protein and water in chilled pork].

    Science.gov (United States)

    Liu, Kui-Wu; Cheng, Fang; Lin, Hong-Jian; Sun, Tong; Xu, Kai; Hu, Lei-Xiu; Ying, Yi-Bin; Xu, Hui-Rong

    2009-01-01

    Fat, protein and water were determined by visible and NIR transmittance spectroscopy in chilled pork. After preprocessed by multiplicative scatter correction (MSC), the quantitative analysis models were developed based on the original, first derivative and second derivative spectra by using partial least squares (PLS) at the temperatures of 0-4 degrees C and 20 degrees C, respectively. By comparing the correlation coefficient (r), RMSEC, and SEP, we found that the first derivative model was the best, and the performance for 0-4 degrees C was better than that for 20 degrees C. At 0-4 degrees C and 20 degrees C, the correlation coefficients were 0.950 and 0.924 for fat, 0.713 and 0.455 for protein and 0.944 and 0.914 for water respectively, SEP values were 2.41 and 2.95 for fat, 5.44 and 4.25 for protein, and 2.37 and 2.38 for water respectively. The results showed that the visible and NIR analysis could measure the fat and water contents in chilled pork well, but was bad for protein, and this was caused by processing line of chilled pork. What's more, the spectrum offset was found in the original spectra at about 770 nm to be about 10 nm.

  20. Hydrogen sulfide is involved in the chilling stress response in Vitis vinifera L.

    Directory of Open Access Journals (Sweden)

    Peining Fu

    2013-11-01

    Full Text Available Hydrogen sulfide (H2S is an important signaling molecule involved in several stress-resistance processes in plants, such as drought and heavy metal stresses. However, little is known about the roles of H2S in responses to chilling stress. In this paper, we demonstrated that chilling stress enhance the H2S levels, the H2S synthetase (L-/D-cysteine desulfhydrase, L/DCD activities, and the expression of L/DCD gene in Vitis vinifera L. ‘F-242’. Furthermore, the seedlings were treated with sodium hydrosulfide (NaHS, a H2S donor and hypotaurine (HT, a H2S scavenger at 4°C to examine the effects of exogenous H2S on grape. The results revealed that the high activity of superoxide dismutase and enhanced expression of VvICE1 and VvCBF3 genes, but low level of super oxide anion radical, malondialdehyde content and cell membrane permeability were detected after addition of NaHS. In contrast, HT treatment displayed contrary effect under the chilling temperature. Taken together, these data suggested that H2S might be directly involved in the cold signal transduction pathway of grape.

  1. Ammonia-Nitrogen Removal during Startup of Biological Process for Treatment of Source Water%水源水生物处理工艺启动中氨氮的去除

    Institute of Scientific and Technical Information of China (English)

    梅翔; 陈洪斌; 张全兴; 高廷耀

    2001-01-01

    The variations of ammonia-nitrogen and nitrite-nitrogen during startup of the biological contact oxidation process for treating slightly polluted source water have been analyzed by using the experimental system with the sedimentation tank and the biochemical tank in series. The research results showed that the growth of Nitrobacter always depended on the conversion of ammonia-nitrogen to nitrite-nitrogen by Nitrosomonas under both no aeration and aeration. The startup during which ammonia-nitrogen removal approached the steady state was such a stage, during which the growth rates and conversion capacities of two groups of nitrifying bacteria approached the steady state, respectively. Sufficient air supply for the biochemical tank was necessary for the steady growth of nitrifying bacteria on the packing materials and the smooth completion of process startup.%通过沉淀槽与生化槽串联的试验系统,分析了微污染水源水生物接触氧化处理工艺启动过程氨氮和亚硝酸盐氮的变化规律。研究结果表明,在无曝气条件下和曝气条件下,填料上硝酸盐细菌的生长均依赖于亚硝酸盐细菌转化氨氮为亚硝酸盐氮的过程。启动中氨氮去除效果趋于稳定的过程是两类硝化细菌在生长速率和转化能力上趋于稳定的过程。提供生化槽充足的曝气量是保证填料上硝化细菌稳定生长,顺利完成启动过程的必要条件。

  2. Start of the big chill for the LHC

    CERN Multimedia

    2007-01-01

    The cooling of Sector 7-8 of the LHC, the first to undergo the process, is under way to the 1.9 K necessary for superconductivity. During the night of 14 to 15 March, an important milestone was reached when the entire sector was cooled to 4.5 K, the temperature of liquid helium. The two graphs above show the progression of cooling in Sector 7-8. The first gives the status of the sector on Tuesday 6 March at 4:00 pm, the second on Wednesday 7 March at 10:00 am. Each square represents a magnet.It's the start of the big chill for the LHC. Since the middle of January, the teams from the Accelerator Cryogenics group have been working to cool down the first sector of the machine. Three kilometres of magnets between Point 7 (Ferney-Voltaire) and Point 8 (Prévessin) are to be cooled to 1.9 Kelvin (-271°C), colder than outer space. The first step in the process was to cool the sector to 80 K. Following mechanical and electrical integrity tests at this temperature, it was then further cooled to 20 K for additional e...

  3. Fracture analysis of chilled cast iron camshaft

    Institute of Scientific and Technical Information of China (English)

    Li Ping; Li Fengjun; Cai Anke; Wei Bokang

    2009-01-01

    The fracture of a camshaft made of chilled cast iron, installed in a home-made Fukang car, happened only after running over a distance of 6,200 km. The fractured camshaft was received to conduct a series of failure analyses using visual inspection, SEM observation of fracture section, microstructure analysis, chemical composition analysis and hardness examination and so on, while those of CKD camshaft made by Citroen Company in France was also simultaneously analyzed to compare the difference between them. The results showed that the fracture of the camshaft mainly results from white section in macrostructure and Ledeburite in microstructure; the crack in the fractured camshaft should be recognized to initiate at the boundary of coarser needle-like carbide and matrix, and then propagate through the transverse section. At the same time, the casting defects such as dendritic shrinkage, accumulated inclusion and initiated crack and abnormal external force might stimulate the fracture of camshaft as well. Based on failure analysis, some measures have been employed, and as a result, the fracture of home-made camshafts has been effectively prevented.

  4. Effect of Low Frequency Electromagnetic Field on Macrosegregation of Horizontal Direct Chill Casting Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    Zhihao ZHAO; Jianzhong CUI; Jie DONG; Beijiang ZHANG

    2005-01-01

    The horizontal direct chill (HDC) casting process is a well-established production route for aluminum alloy ingot but the ingot may suffer from macrosegregation sometimes. In order to control the defect, a low frequency electromagnetic field has been applied in HDC casting process and the relevant influence has been studied. The results show that application of low frequency electromagnetic field can reduce macrosegregation in HDC casting process; and two main parameters of electromagnetic field density and frequency, have great influences on the solution distribution along the diameter of ingot. Moreover, the mechanisms of reduction of macrosegregation by electromagnetic field have been discussed.

  5. Biofilter Treating Ammonia Gas Using Agricultural Residues Media

    Directory of Open Access Journals (Sweden)

    Thaniya Kaosol

    2012-01-01

    Full Text Available Problem statement: Agricultural residues such as manure and sugarcane bagasse are wastes from agro-industry which has low value and requires some sustainable waste management method. In this research, a mixture of manure fertilizer and sugarcane bagasse is used as a biofilter media for an ammonia gas removal application. The aim of this research is to study the ammonia gas removal efficiency of such media. Approach: The experiments were conducted in laboratory-scale biofilters. Two inlet ammonia gas concentrations were used which are 500 and 1,000 ppm. Three ratios of manure fertilizer and sugarcane bagasse were studied including 1:3, 1:5 and 1:7 by volume. All experiments were conducted for a period of 40 days. Two Empty Bed Retention Time (EBRT of these experiments were used which is 39s and 78s. The moisture content of the biofilter media was maintained at 45-60% by adding water. Results: The maximum ammonia gas removal efficiency at 89.93% is observed from the following conditions: 500 ppm of the inlet ammonia gas concentration, the manure fertilizer and sugarcane bagasse mixture ratio of 1:5 and the EBRT of 78s. The important factors of the ammonia gas removal in biofiltration process are the inlet ammonia gas concentration and the EBRT. Conclusion: The experimental results showed that the mixture of manure fertilizer and sugarcane bagasse is an effective biofilter media for ammonia gas removal applications. However, the biofilter is more effective at low inlet ammonia gas concentration, while the ratio of manure fertilizer and sugarcane bagasse has no significant effect on the ammonia gas removal efficiency. Therefore, using both residues as biofilter media for ammonia gas removal application is an alternative sustainable way to such manage argo-industry waste.

  6. Review of Options for Ammonia/Ammonium Management

    Energy Technology Data Exchange (ETDEWEB)

    Nash, C. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-05-06

    This report is a review of literature supporting practical ammonia/ammonium destruction processes. Melter research supporting Hanford Low Activity Waste (LAW) glass production has shown that significant amounts of ammonia will be in the melter offgas condensate. Further work with secondary waste forms indicates the potential need to remove the ammonia, perhaps by an oxidative process. This review finds likely practical chemical methods to oxidize ammonia in aqueous solution at moderate temperatures and atmospheric pressure, using easily obtained reagents. Leading candidates include nitrite oxidation to produce nitrogen gas, various peroxide oxidative processes, and air stripping. This work reviews many other processes and provides reasoning to not consider those processes further for this application.

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

    Science.gov (United States)

    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

  8. Ammonia effect on hydrogenotrophic methanogens and syntrophic acetate oxidizing bacteria

    DEFF Research Database (Denmark)

    Wang, Han; Fotidis, Ioannis; Angelidaki, Irini

    2015-01-01

    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, Methanoculleus thermophilus and Methanothermobacter thermautotrophicus), two SAOB (i.e. Tepidanaerobacter acetatoxydans and Thermacetogenium phaeum) and their syntrophic cultivation, were assessed under 0...

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

    Science.gov (United States)

    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 %.

  10. Study of ammonia process generation from the avian residues aiming the hydrogen production; Estudo do processo da geracao de amonia a partir de residuos avicolas visando a producao de hidrogenio

    Energy Technology Data Exchange (ETDEWEB)

    Egute, Nayara dos Santos; Abrao, Alcidio; Carvalho, Fatima Maria Sequeira de [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: nayara.egute@usp.br

    2010-03-15

    The hydrogen used in fuel cells can be classified as green or black hydrogen. Ammonia as an hydrogen source has the great advantage of being carbon-free. One of the sources of ammonia is poultry and egg production systems. In these systems the ammonia is produced from the decomposition of uric acid present in the excreta of birds. Among the factors which influence the ammonia volatilization, are the pH and the nitrogen content. Poultry litter and excreta isolated were also analyzed, The addition of sodium carbonate, with the rise of pH promoted an increase in the levels of ammonia volatilization. The high nitrogen excreta presented higher ammonia volatilization than the other one. The excreta was considered more appropriate than poultry litter for the objectives of this work due to the higher ammonia concentrations determined int his material. (author)

  11. Determination of unidirectional heat transfer coefficient during unsteady-state solidification at metal casting-chill interface

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, Haci Mehmet [Gazi Ueniversitesi, Teknik Egitim Fakueltesi, Teknikokullar, Ankara 06503 (Turkey)]. E-mail: mesahin@gazi.edu.tr; Kocatepe, Kadir [Gazi Ueniversitesi, Teknik Egitim Fakueltesi, Teknikokullar, Ankara 06503 (Turkey); Kayikci, Ramazan [Sakarya Ueniversitesi, Teknik Egitim Fakueltesi, Sakarya (Turkey); Akar, Neset [Gazi Ueniversitesi, Teknik Egitim Fakueltesi, Teknikokullar, Ankara 06503 (Turkey)

    2006-01-15

    In this study, the interfacial heat transfer coefficient (IHTC) for vertically upward unidirectional solidification of a eutectic Al-Si casting on water cooled copper and steel chills was measured during solidification. A finite difference method (FDM) was used for solution of the inverse heat conduction problem (IHCP). Six computer guided thermocouples were connected with the chill and casting, and the time-temperature data were recorded automatically. The thermocouples were placed, located symmetrically, at 5 mm, 37.5 mm and 75 mm from the interface. As the lateral surfaces are very well heat isolated, the unidirectional solidification process starts vertically upward at the interface surface. The measured time-temperature data files were used by a FDM using an explicit technique. A heat flow computer program has been written to estimate the transient metal-chill IHTC in the IHCP. The experimental and calculated temperatures have shown excellent agreement. The IHTC during vertically upward unidirectional solidification of an Al-Si casting on copper and steel chills have varied between about 19-9.5 kW/m{sup 2} K and 6.5-5 kW/m{sup 2} K, respectively.

  12. Evaluation of trigeneration system using microturbine, ammonia-water absorption chiller, and a heat recovery boiler

    Energy Technology Data Exchange (ETDEWEB)

    Preter, Felipe C.; Rocha, Marcelo S.; Simoes-Moreira, Jose Roberto [SISEA - Alternative Energy Systems Lab. Dept. of Mechanical Engineering. University of Sao Paulo (EP/USP), SP (Brazil)], e-mails: felipe.preter@poli.usp.br, msrocha@poli.usp.br, jrsimoes@usp.br; Andreos, Ronaldo [COMGAS - Companhia de Gas de Sao Paulo, SP (Brazil)], e-mail: randreos@comgas.com.br

    2010-07-01

    In this work, a CCHP or tri generation system has been projected, mounted, and tested in laboratory, combining a microturbine for power generation, a heat recovery boiler for hot water production, and an ammonia water absorption chiller for chilled water production. The project was motivated by the large practical applications of this kind of energy recovery system in commerce, and industry, and, in general, more than 85% of the energy source is used as power, hot water, and cold water. In the first part, the trigeneration system theoretical model is detailed, and in the second part, experimental results are presented for different operation conditions. (author)

  13. Ammonia Processing Technology in A Recirculating System in Industrial Aquaculture:A Review%工厂化水产养殖水中氨氮处理技术的研究

    Institute of Scientific and Technical Information of China (English)

    韩世成; 郭常有; 蒋树义; 曹广斌

    2014-01-01

    氨氮处理技术是工厂化水产养殖的关键技术之一。本文综述国内外工厂化养殖中常用的氨氮处理方法,如空气吹脱、离子交换吸附、微生物处理、臭氧氧化处理、沉水植物处理等,分析各种方法的优缺点,论证LED特定光照沉水植物处理氨氮方法的优势、可行性和发展方向,为实际应用和新技术开发提供参考。%Ammonia processing technology as a key in a recirculating aquaculture system is summarized including a bubble-washed bead filter, ion exchange and adsorption, microorganism treatment, and use of ozone and submerged plants. The advantages and disad-vantages of these methods are evaluated, and a new method, specific LED light irradiation submerged plants handling ammonia, is in-troduced. The future researches on those methods are discussed to provide a base for practice application.

  14. Selection and Execution for Process Scheme of Synthetic Ammonia Made by Coke-Oven Gas%焦炉煤气制合成氨工艺方案的选取和实施

    Institute of Scientific and Technical Information of China (English)

    文德国; 苏庆贺; 陈世通

    2014-01-01

    介绍了山东临沂恒昌化工科技有限公司焦炉煤气制合成氨装置的立项背景;确定了装置的工艺方案和主要设备;简述了装置节能降耗的主要措施。结果表明:该装置一次试车成功,吨氨电耗约1000 kW· h,制造成本约1500元/t,经济效益明显。%Author has introduced the project approval background for plant of synthetic ammonia made by coke-oven gas in the Shandong Linyi Hengchang Chemical Engineering Science and Technology Company Ltd .; has determined the process scheme and main equipment; has described the main measures about energy saving and consume lowering.Result indicates that the trial run of plant was succesful in one time, the electricity power per ton of ammonia is saved by 1 000 kW· h, fabrication cost is saved by 1 500 Yuan RMB per ton, the economic benefit is obvious.

  15. Preparation of grade zinc oxide f rom blast furnace dust by using ammonia process%氨法处理高炉瓦斯灰制取等级氧化锌研究

    Institute of Scientific and Technical Information of China (English)

    张保平; 杨芳

    2014-01-01

    以氨-碳酸氢铵混合液为浸出剂浸出高炉瓦斯灰中的有价金属锌,经净化、蒸氨、煅烧得到等级氧化锌,对相关工艺参数进行优化选择。结果表明,最佳浸出条件为:[氨水]/[N H4 HCO3]=2、液固比为4、总氨浓度为5mol·L -1,浸出时间为3h,此条件下锌浸出率为82.55%;最佳净化条件为:锌粉用量为1.5g·L -1、净化时间为2.5h,此条件下铅的脱除率为97.70%;最佳蒸氨条件为90℃下蒸氨至终点溶液pH值为6~7,此条件下蒸氨后锌的沉淀率可达99.95%。沉淀物在500℃下煅烧1 h ,得到纯度为96.03%的氧化锌粉末,达到了H G/T 2527-94的一级标准。%Given the valuable metal zinc in blast furnace dust ,the grade zinc oxide was prepared from blast furnace dust by the process of leaching with ammonia-ammonium ,purification with zinc pow-der ,ammonia still process and calcination .The results show that the optimal conditions of leaching are the ratio of the concentration of ammonia to that of ammonium being 2 ,the ratio of liquid to solid being 4 ,the total ammonia concentration being 5 mol · L -1 ,and the leaching time being 3 hours ,un-der which the extraction rate of zinc is 82 .55% ;the optimal conditions of purification are that the con-sumption of zinc powder is 1 .5 g · L -1 ,the purification time is 2 .5 hours ,under which the desorption rate of Pb is 97 .70% ;and the optimal conditions of ammonia still process are that the temperature is 90 ℃ and pH value of pH is 6 to 7 ,under w hich the precipitation rate of zinc is 99 .95% .Calcined at 500 ℃ for 1 hour ,the content of zinc oxide powder is 96 .03% ,which complies with the primary standard of HG/T2527-94 .

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

    Science.gov (United States)

    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.

  17. Amelioration of Chilling Injuries in Watermelon Seedlings by Abscisic Acid

    OpenAIRE

    Korkmaz, Ahmet

    2002-01-01

    A greenhouse study, designed in a randomized complete block design with five replications, was carried out at Clemson University, Clemson, SC, USA, in the spring of 1997. The objective of the study was to investigate whether abscisic acid (ABA) would mitigate chilling damages in the watermelon, a chilling-sensitive plant. 'Crimson Sweet' [Citrullus lanatus (Thumb) Matsum. & Nakai.] watermelon seedlings were grown in a greenhouse with a temperature regime of 25ºC (day) and 20ºC...

  18. Fast responsive, optical trace level ammonia sensor for environmental monitoring

    OpenAIRE

    Abel Tobias; Ungerböck Birgit; Klimant Ingo; Mayr Torsten

    2012-01-01

    Abstract Background Ammonia is a ubiquitous chemical substance which is created in technical and biological processes and harmful to many different organisms. One specific problem is the toxicity of ammonia in fish at levels of 25 μg/l - a very common issue in today’s aqua culture. In this study we report a development of a fast responsive, optical ammonia sensor for trace concentrations. Results Different hydrogels have been investigated as host polymers for a pH based sensing mechanism base...

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

    Science.gov (United States)

    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

  20. Ammonia tolerant enriched methanogenic cultures as bioaugmentation inocula to alleviate ammonia inhibition in continuous anaerobic reactors

    DEFF Research Database (Denmark)

    Fotidis, Ioannis; Wang, Han; Angelidaki, Irini

    . The bioaugmentation was performed without pausing the continuous operation of the CSTR reactor and without excluding the ammonia-rich substrate from the feedstock. Thus, bioaugmentation with mixed methanogenic cultures could potentially support the development of an efficient and cost-effective biomethanation process...... of a pure culture, to be used as bioaugmentation inoculum, poses technical difficulties due to the required sterile conditions and the special growing media. On the contrary acclimatized enrichment methanogenic cultures have lower requirements to sterility. In the present study, we used an enriched ammonia...... tolerant methanogenic culture as potential bioaugmentation inoculum in a continuous stirred tank reactor (CSTR) operating under “inhibited steady-state”, triggered by high ammonia levels (5 g NH4+-N L-1). The results of the current study established for the first time that bioaugmentation of an enriched...

  1. Livestock wastewater treatment: ammonia removal

    International Nuclear Information System (INIS)

    Livestock wastewater contains high concentration of ammonia. Removal of this inorganic species of nitrogen could be achieved through nitrification and de-nitrification. Nitrification process was conducted in the laboratory using activated sludge process with HRT of three and five days. After wastewater undergone nitrification process at Livestock Wastewater Treatment Plant the concentration of influent for N-NH4+ reduced from 400 mg/l to 0 mg/l and concentration of N-NO3- increased from 11 mg/l to 300 mg/l. Nitrification using lab-scale activated sludge process also recorded similar result. Concentration of N-NH4+ reduced from 400 mg/l to 2 mg/l and 380 mg/l to 1.1 mg/l for HRT=5 days and HRT=3 days respectively. N-NO3- was increased from 11 mg/l to 398 mg/l and 14 mg/l to 394 mg/l for HRT=5 days and HRT=3 days, respectively. However changes of N-NH4+ and N=NO3- were not observed using gamma irradiation. The combination of gamma irradiation with activated sludge process indicated difference and its contribution is still investigated

  2. EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF); Flavouring Group Evaluation 46, Revision 1 (FGE.46Rev1): Ammonia and three ammonium salts from chemical group 30

    DEFF Research Database (Denmark)

    Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;

    The Scientific Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (the Panel) was asked to provide scientific advice to the Commission on the implications for human health of chemically defined flavouring substances used in or on foodstuffs in the Member States. In particular...... or optical isomers. Two of the flavouring substances are classified into structural class I and two are classified into structural class III according to the decision tree approach presented by Cramer et al. (1978). The flavouring substance ammonia in the present group has been reported to occur naturally...... substances in Europe. However, when the Panel examined the information provided by the European Flavouring Industry on the use levels in various foods, it appeared obvious that the MSDI approach in a number of cases would grossly underestimate the intake by regular consumers of products flavoured at the use...

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

    Science.gov (United States)

    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…

  4. 77 FR 10772 - Fresh and Chilled Atlantic Salmon From Norway

    Science.gov (United States)

    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...

  5. Transcript profiling of Paoenia ostii during artificial chilling induced dormancy release identifies activation of GA pathway and carbohydrate metabolism.

    Directory of Open Access Journals (Sweden)

    Shupeng Gai

    Full Text Available 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.

  6. Global Ecological Pattern of Ammonia-Oxidizing Archaea

    OpenAIRE

    Huiluo Cao; Jean-Christophe Auguet; Ji-Dong Gu

    2013-01-01

    BACKGROUND: The global distribution of ammonia-oxidizing archaea (AOA), which play a pivotal role in the nitrification process, has been confirmed through numerous ecological studies. Though newly available amoA (ammonia monooxygenase subunit A) gene sequences from new environments are accumulating rapidly in public repositories, a lack of information on the ecological and evolutionary factors shaping community assembly of AOA on the global scale is apparent. METHODOLOGY AND RESULTS: We condu...

  7. Catalytic ammonia oxidation to nitrogen (I) oxide

    OpenAIRE

    MASALITINA NATALIYA YUREVNA; SAVENKOV ANATOLIY SERGEEVICH

    2015-01-01

    The process of synthesis of nitrous oxide by low-temperature catalytical oxidation of NH has been investigated for organic synthesis. The investigation has been carried out by the stage separation approach with NH oxidation occurring in several reaction zones, which characterized by different catalytic conditions. The selectivity for N₂O was 92–92,5 % at the ammonia conversion of 98–99.5 % in the optimal temperature range.

  8. Use of MBR Process in Wastewater Treatment of Synthetic Ammonia Industry%MBR 工艺在合成氨工业废水处理中的应用

    Institute of Scientific and Technical Information of China (English)

    魏维刚; 刘岚

    2015-01-01

    Membrane bioreactor (MBR) is a high efficient wastewater biological treatment process which combines wastewater biological treatment technology and membrane separation technology,and can treat high ammonia-nitrogen content wastewater generated by synthetic ammonia industry effectively.After putting into operation of the MBR systems,COD content of effluent is less than 70 mg/L,ammonia-nitrogen content is stabilized less than 25 mg/L,water yield of each of the 2 MBR systems is 150 m3 /h,reaching the design requirements.The actual operation for more than one year shows that the wastewater treatment system provides a reliable guarantee for energy conservation and emission reduction of the enterprise,but some problems have appeared during operation,effectively solving these problems is crucial to long-term and stable running of the wastewater treatment station.%膜生物反应器(MBR)是将污水的生物处理技术与膜分离技术相结合的高效废水生物处理工艺,可有效处理合成氨工业产生的高 NH3-N 含量的废水。MBR 投运后,出水 COD 含量<70 mg/L,NH3-N 含量可稳定在<25 mg/L,2套 MBR 系统的产水量均为150 m3/h,达到了设计要求。1年多的实际运行情况表明,该污水处理系统为企业的节能减排提供了可靠保障,但运行中也出现了一些问题,这些问题的有效解决对废水处理站的长期稳定运行至关重要。

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

    Science.gov (United States)

    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.

  10. Lattice dynamics of ammonia

    International Nuclear Information System (INIS)

    The frequencies of selected intermolecular modes of vibration and libration in a single crystal of deuterated ammonia (ND3) have been measured by the technique of coherent inelastic neutron scattering, at temperatures of 20 and 95K. The results are compared with the previous optical measurements at the Γ point, and with calculations based on two different models for the intermolecular potential function. A detailed assessment of these data leads to a set of mode frequencies for the Γ, R, and M points. The elastic constants are calculated from the measured acoustic mode dispersion curves propagating along the three major symmetry directions. The existing intermolecular force models are in good qualitative agreement with experiment, but significant discrepancies remain to be resolved by future theoretical refinements. (author)

  11. Effects of low-frequency magnetic field on grain boundary segregation in horizontal direct chill casting of 2024 aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Effects of low frequency electromagnetic field on grain boundary segregation in horizontal direct chill (HDC)casting process was investigated experimentally. The grain boundary segregation and microstructures of the ingots,which manufactured by conventional HDC casting and low frequency electromagnetic HDC casting were compared.Results show that low frequency electromagnetic field significantly refines the microstructures and reduces grain boundary segregation. Decreasing electromagnetic frequency or increasing electromagnetic intensity has great effects in reducing grain boundary segregation. Meanwhile, the governing mechanisms were discussed.

  12. Autotrophic ammonia oxidation at low pH through urea hydrolysis.

    Science.gov (United States)

    Burton, S A; Prosser, J I

    2001-07-01

    Ammonia oxidation in laboratory liquid batch cultures of autotrophic ammonia oxidizers rarely occurs at pH values less than 7, due to ionization of ammonia and the requirement for ammonium transport rather than diffusion of ammonia. Nevertheless, there is strong evidence for autotrophic nitrification in acid soils, which may be carried out by ammonia oxidizers capable of using urea as a source of ammonia. To determine the mechanism of urea-linked ammonia oxidation, a ureolytic autotrophic ammonia oxidizer, Nitrosospira sp. strain NPAV, was grown in liquid batch culture at a range of pH values with either ammonium or urea as the sole nitrogen source. Growth and nitrite production from ammonium did not occur at pH values below 7. Growth on urea occurred at pH values in the range 4 to 7.5 but ceased when urea hydrolysis was complete, even though ammonia, released during urea hydrolysis, remained in the medium. The results support a mechanism whereby urea enters the cells by diffusion and intracellular urea hydrolysis and ammonia oxidation occur independently of extracellular pH in the range 4 to 7.5. A proportion of the ammonia produced during this process diffuses from the cell and is not subsequently available for growth if the extracellular pH is less than 7. Ureolysis therefore provides a mechanism for nitrification in acid soils, but a proportion of the ammonium produced is likely to be released from the cell and may be used by other soil organisms.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Fuwang Wu

    2016-09-01

    Full Text Available 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.

  16. Ammonia Ice Clouds on Jupiter

    Science.gov (United States)

    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.

  17. PROCESS ANALYSIS AND OPTIMIZATION OF AMMONIA BURNING IN A SULFUR RECOVERY UNIT%硫磺回收装置烧氨过程分析及条件优化

    Institute of Scientific and Technical Information of China (English)

    马恒亮; 唐战胜; 耿庆光

    2012-01-01

    对中国石化洛阳分公司硫磺回收装置在烧氨过程中遇到的问题进行分析,结合实际操作情况,提出烧氨条件优化方案.结果表明,适当提高风气比、提高酸性气进炉温度、调节燃烧气氨的负荷和优化仪表控制方案后,一、二级反应器的入口和床层间的温差均增大,系统压力基本维持在0.038MPa左右,急冷水中NH3-N质量浓度控制在300 mg/L左右,取得了较好的综合效益.%After a period of operation and analysis, the process conditions of ammonia burning at the sulfur recovery unit of SINOPEC Luoyang Branch Company were optimized. Results showed that by increasing the air/feed gas volume ratio and the inlet temperature of sour gas to furnace, adjusting the volume fraction of ammonia in sour gas and optimizing instrumentation and control, the temperature difference of reactor inlet and bed layer increased to ensure fully reactions; the system pressure was maintained at 0. 038 MPa and the NH3-N content in quench water was around 300 mg/L. Good economic, environmental and social benefits were obtained.

  18. Rapid and dissimilar response of ammonia oxidising archaea and bacteria to nitrogen and water amendment in two temperate forest soils

    OpenAIRE

    Szukics, Ute; Hackl, Evelyn; Zechmeister-Boltenstern, Sophie; Sessitsch, Angela

    2011-01-01

    Biochemical processes relevant to soil nitrogen (N) cycling are performed by soil microorganisms affiliated with diverse phylogenetic groups. For example, the oxidation of ammonia, representing the first step of nitrification, can be performed by ammonia oxidizing bacteria (AOB) and, as recently reported, also by ammonia oxidizing archaea (AOA). However, the contribution to ammonia oxidation of the phylogenetically separated AOA versus AOB and their respective responsiveness to environmental ...

  19. Distribution of Ammonia-Oxidizing Archaea and Bacteria in the Surface Sediments of Matsushima Bay in Relation to Environmental Variables

    OpenAIRE

    Sakami, Tomoko

    2011-01-01

    Ammonia oxidization is the first and a rate-limiting step of nitrification, which is often a critical process in nitrogen removal from estuarine and coastal environments. To clarify the correlation of environmental conditions with the distribution of ammonia oxidizers in organic matter-rich coastal sediments, ammonia-oxidizing archaea (AOA) and bacteria (AOB) ammonia monooxygenase alpha subunit gene (amoA) abundance was determined in sediments of Matsushima Bay located in northeast Japan. The...

  20. Ammonia regeneration for a combined lime/ammonia spray dryer for SO{sub 2} control. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Xinjian, Yang [Cincinnati Univ., OH (United States). Dept. of Civil and Environmental Engineering

    1992-12-23

    A research project designed to study the feasibility of ammonia regeneration for a combined lime/ammonia FGD process was conducted at the University of Cincinnati. The major objective for this project was to regenerate ammonia from a combined ammonia/calcium hydroxide spray dryer FGD byproduct for reuse which would reduce the operating cost of this FGD process. This final report covers the six phases of the project: (1) generation of original feedstock, (2) batch regeneration studies, (3) continuous regeneration studies, (4) waste characteristic analysis, (5) pilot scale demonstration and (6) economic analysis. This research has shown that regeneration of ammonia is feasible at a reasonable cost. The effects on Ohio coal use from the results of this research could be substantial, depending on the Phase II application of FGD systems for controlling SO{sub 2} emissions. In conclusion, experiments in this study have shown that ammonia recovery efficiencies greater than 90% are technically and economically feasible. In addition, the sludge produced from the regeneration process is stable and will meet existing Federal standards.

  1. Ammonia effect on hydrogenotrophic methanogens and syntrophic acetate oxidizing bacteria

    DEFF Research Database (Denmark)

    Wang, Han; Fotidis, Ioannis; Angelidaki, Irini

    methanogens. Two pure strains of hydrogenotrophic methanogens (i.e: Methanoculleus bourgensis and Methanoculleus thermophiles) and two pure strains of SAO bacteria (i.e: Tepidanaerobacter acetatoxydans and Thermacetogenium phaeum) were inoculated under four different ammonia (0.26, 3, 5 and 7g NH4+-N......, the total incubation periods of hydrogenotrophic methanogens were significantly shorter compared to the SAO bacteria incubation periods. Thus, it seems that hydrogenotrophic methanogens could be equally, if not more, tolerant to high ammonia levels compared to SAO bacteria.......Substrates that contain high ammonia levels can cause inhibition on anaerobic digestion process and unstable biogas production. The aim of the current study was to assess the effects of different ammonia levels on pure strains of (syntrophic acetate oxidizing) SAO bacteria and hydrogenotrophic...

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

    Science.gov (United States)

    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.

  3. [Visualization of the chilling storage time for turbot flesh based on hyperspectral imaging technique].

    Science.gov (United States)

    Zhu, Feng-Le; Zhang, Hai-Liang; Shao, Yong-Ni; He, Yong

    2014-07-01

    This study proposed a new method using visible and near infrared (Vis/NIR) hyperspectral imaging for the detection and visualization of the chilling storage time for turbot flesh rapid and nondestructively. A total of 160 fish samples with 8 different storage days were collected for hyperspectral image scanning, and mean spectra were extracted from the region of interest (ROD inside each image. Partial least squares regression (PLSR) was applied as calibration method to correlate the spectral data and storage time for the 120 samples in calibration set. Then the PLSR model was used to predict the storage time for the 40 prediction samples, which achieved accurate results with determination coefficient (R2) of 0.966 2 and root mean square error of prediction (RMSEP) of 0.679 9 d. Finally, the storage time of each pixel in the hyperspectral images for all prediction samples was predicted and displayed in different colors for visualization based on pseudo-color images with the aid of an IDL program. The results indicated that hyperspectral imaging technique combined with chemometrics and image processing allows the determination and visualization of the chilling storage time for fish, displaying fish freshness status and distribution vividly and laying a foundation for the automatic processing of aquatic products.

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

    Science.gov (United States)

    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

  5. Ammonia-oxidizing archaea have more important role than ammonia-oxidizing bacteria in ammonia oxidation of strongly acidic soils

    OpenAIRE

    Zhang, Li-Mei; Hu, Hang-Wei; Shen, Ju-Pei; He, Ji-Zheng

    2011-01-01

    Increasing evidence demonstrated the involvement of ammonia-oxidizing archaea (AOA) in the global nitrogen cycle, but the relative contributions of AOA and ammonia-oxidizing bacteria (AOB) to ammonia oxidation are still in debate. Previous studies suggest that AOA would be more adapted to ammonia-limited oligotrophic conditions, which seems to be favored by protonation of ammonia, turning into ammonium in low-pH environments. Here, we investigated the autotrophic nitrification activity of AOA...

  6. 21 CFR 573.180 - Anhydrous ammonia.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Anhydrous ammonia. 573.180 Section 573.180 Food... Additive Listing § 573.180 Anhydrous ammonia. (a) The food additive anhydrous ammonia is applied directly...: (1)(i) The food additive anhydrous ammonia is applied as a component of an aqueous premix...

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  10. Manufacture of Catalyst Systems for Ammonia Conversion

    Institute of Scientific and Technical Information of China (English)

    GAKH S.V.; SAVENKOV D.A.

    2012-01-01

    Platinum catalyst gauzes have been in use since the moment of development of the process of catalyst oxidation of ammonia for production of nitric acid or hydrocyanic acid.Catalyst gauzes are usually made of platinum or its alloys with rhodium and palladium.These precious metals have remarkable properties that make them ideal catalysts for acceleration of the ammonia/oxygen reaction.In 2008,OJSC "SIC ‘Supermetal’" and Umicore AG&Co.KG launched a production line for Pt-alloy-based catalyst systems to be used for ammonia oxidation in the production of weak nitric acid.Catalyst systems consist of a pack of catalyst gauzes and a pack of catchment gauzes,which are made using flat-bed knitting machines and wire-cloth looms.Today,up-to-date catalyst systems MKSpreciseTM are being manufactured,the basic advantages of which are an individual structure of gauzes and composition of the material,which allows to define precisely the position of each gauze in the catalyst pack,a high activity of the catalyst pack,direct catching of platinum and rhodium in the catalyst system,and a reasonable combination of single- and multilayer types of gauzes.This makes it possible to vary the configuration of the catalyst and select an optimum composition of the system to ensure the maximum efficiency of the ammonia oxidation process.We also produce the catchment systems that allow to find the best decision from the economic point view for each individual case.

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

    Science.gov (United States)

    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 ...

  12. Chilling Tolerance Improving of Watermelon Seedling by Salicylic Acid Seed and Foliar Application

    Directory of Open Access Journals (Sweden)

    Mohammad SAYYARI

    2013-02-01

    Full Text Available Chilling temperatures lead to numerous physiological disturbances in the cells of chilling-sensitive plants and result in chilling injury and death of tropical and subtropical plants such as watermelon. In this study, the possibility of cold stress tolerance enhancing of watermelon seedling (Citrullus lanatus by exogenous application of Salicylic acid (SA was investigated. SA was applied through seed soaking or foliar spray at 0, 0.5, 1 and 1.5 mM concentration. After SA treatment, the seedlings were subjected to chilling 5 h/day at 4°C for 5 days. Statistical analysis showed significant effects of the application methods and SA concentrations on plant growth parameters, photosynthetic pigments, electrolyte leakage, proline and chilling injury index. SA application improved growth parameters and increased chlorophyll content of watermelon seedling subjected to chilling stress and provided significant protection against chilling stress compared to non-SA-treated seedlings. Although two SA application methods improved chilling stress tolerance, seed soaking method provided better protection compared to foliar spray method. SA ameliorated the injury caused by chilling stress via inhibiting proline accumulation and leaf electrolyte leakage. The highest cold tolerance was obtained with 0.5 mM SA application. Results indicate that SA could be used effectively to protect watermelon seedling from damaging effects of chilling stress at the early stages of growth.

  13. Recrystallization and crystallographic texture in AA4006 aluminum alloy sheets produced by twin roll caster and direct chill processes Recristalização e textura cristalográfica de chapas produzidas por lingotamento contínuo e semicontínuo da liga de alumínio AA4006

    Directory of Open Access Journals (Sweden)

    Fabrício Mendes Souza

    2012-09-01

    Full Text Available A recrystallization study of cold rolled metallic sheets is very important to evaluate the softening temperature for subsequent annealing. Crystallographic texture evolves during metal rolling and recrystallization. These processing steps can lead to an optimization of the grain orientation distribution in a metal strip and can improve, for instance, the stamping process, hence leading to a product with aggregated value. Softening curves were determined and compared for two sheets of the AA4006 aluminum alloy produced by the twin roll caster-TRC and by the direct chill-DC (under industrial process condition. It has been detected that the recrystallization of the strip produced by TRC process occurs at a higher temperature than the produced by DC process despite the little differences in their softening curves. The precipitation, in the TRC strip sample, occurs mainly before recrystallization and may occur during recrystallization. There is precipitation occurrence before and during recrystallization more expressive in the DC strip sample. Crystallographic texture of the sheet samples was obtained by X-ray diffraction and electron back scattering diffraction (EBSD techniques. Results indicated the presence of a shear texture at the surface and β-fiber at the center of the cold rolled (70% area reduction sample for the sheet produced by TRC process. In the strip sample obtained by the DC process, under the same conditions, the cube component and the β-fiber on the surface and at the center were observed. A random oriented grain texture has been detected in the two (TRC and DC recrystallized (after cold rolling sheet samples possibly due to the particle stimulated nucleation. The absence of β fiber in the recrystallized samples (TRC and DC has also been observed.O estudo da recristalização de chapas metálicas laminadas a frio é muito útil para a obtenção da temperatura de amolecimento do material submetido a um tratamento térmico. Al

  14. Solubility of ammonia in rainwater

    OpenAIRE

    G. P. Ayers; Gras, J. L.; Adriaansen, A.; Gillett, R. W.

    2011-01-01

    Partitioning of ammonia between the gaseous and rainwater phases has been investigated at theAustralian Baseline Air Pollution Station during in-situ experiments in which rainwater andammonia gas were sampled concurrently. The relationship between ammonia concentrations inthe gaseous and aqueous phases did not follow either traditional solubility theory based onHenry’s Law, or a recent modified theory that includes secondary equilibria between dissolvedammonia and carbon dioxide.DOI: 10.1111/...

  15. Ammonia oxidizing bacteria and archaea in horizontal flow biofilm reactors treating ammonia-contaminated air at 10 °C.

    Science.gov (United States)

    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

  16. AMMONIA AND COD REMOVAL FROM SYNTHETIC LEACHATE USING RICE HUSK COMPOSITE ADSORBENT

    Directory of Open Access Journals (Sweden)

    Azhar Abdul Halim

    2011-06-01

    Full Text Available Ammonia and chemical oxygen demand (COD were the most two problematic parameters in the landfill leachate. In this study, a new composite adsorbent derived from rice husk ash waste is evaluated with respect to its ability to remove these contaminants from synthetic leachate. Results indicate that the new composite adsorbent is able to adsorb both ammonia and COD. It has a higher adsorption capacity for ammonia (Q = 2.2578 mg/g and an almost equal adsorption capacity for COD (Q = 2.8893 when compared with commercially activated carbon. The adsorption kinetics of this new product for ammonia and COD were primarily represented by the pseudo second-order mechanism. The overall adsorption rate of the ammonia and COD adsorption processes appears to be determined by chemisorption process. The regenerated composite adsorbent indicated higher adsorption capacities of ammonia and COD, i.e. 12.9366 mg/g and 3.1162 mg/g, respectively.

  17. ChillFish: A Respiration Game for Children with ADHD

    DEFF Research Database (Denmark)

    Sonne, Tobias; Jensen, Mads Møller

    Breathing exercises can help children with ADHD control their stress level, but it can be hard for a child to sustain attention throughout such an exercise. In this paper, we present ChillFish, a breath-controlled biofeedback game designed in collaboration with ADHD professionals to investigate...... the possibilities of combining breathing exercises and game design. Based on a pilot study with 16 adults, we found that playing ChillFish had a positive effect, helping the participants to reach a relaxed state similar to the one offered by traditional breathing exercises. Further, we analyze the opportunities...... and challenges of creating a tangible respiration-based controller and use it as a core game mechanic. Finally, we discuss the challenge of balancing engagement and relaxation in physically controlled games for children with ADHD in order to make a game that can be calming and still sustain their attention....

  18. Action of Cryogenic chill on Mechanical properties of Nickel alloy Metal Matrix Composites

    Science.gov (United States)

    Kumar, B. K. Anil; Ananthaprasad, M. G.; GopalaKrishna, K.

    2016-09-01

    In the area of material science engineering, metallurgists may be at the forefront of new technologies, developing metals for new applications, or involved in the traditional manufacture. By doing so it is possible for metallurgist to apply their knowledge of metals to solve complex problems and looking for ways to improve the mechanical properties of the materials. Therefore, an investigation in the present research was made to fabricate and evaluate the microstructure and mechanical properties of composites developed using cryogenically cooled copper chills, consisting of nickel alloy matrix and garnet particles as the reinforcement. The reinforcement being added ranges from 3 to 12 wt.% in steps of 3%. A stir casting process was used to fabricate the nickel base matrix alloy fused with garnet reinforcement particle. The matrix alloy was melted in a casting furnace at around 1350°C, the garnet particulates which was preheated to 600°C, was introduced evenly into the molten metal alloy. An arrangement was made at one end of the mould by placing copper chill blocks of varying thickness brazed with MS hallow block in which liquid nitrogen was circulated for cryogenic effect. After solidification, the composite materials thus synthesized were examined for microstructural and mechanical properties as per ASTM standards.

  19. A new method for chill and shrinkage control in ladle treated ductile iron

    Institute of Scientific and Technical Information of China (English)

    Torbj(o)rn Skaland

    2006-01-01

    The paper is undertaken with the objective of describing a new method for treating ductile cast iron in a ladle process, where the main objective is to minimize formation of eutectic carbides and shrinkage porosity during solidification. The suppression of carbide formation is associated with the nucleating properties of the nodularizer and inoculant alloys. By nucleating properties it is understood the number and potency of nuclei formed by an alloy addition. The nodularizer and inoculant additions also influence ductile iron solidification shrinkage. Some alloys may give good protection against shrinkage while others tend to promote more shrinkage.The use of vanous rare earth elements is found to have a pronounced impact on these conditions. It has been discovered that the use of pure lanthanum as the primary rare earth source in the magnesium ferrosilicon nodularizer surprisingly further improves the performance of the ductile iron ladle treatment method compared to similar methods using cerium or mishmetal bearing nodularizers. The nucleating properties are substantially improved and the risk for carbides (chill) and shrinkage formation in the sandwich or tundish ladle treated ductile iron is then minimized.The paper describes this new ladle treatment concept in detail, and gives examples from successful testing of the new nodularizing technology and how it simultaneously affects and minimizes critical ductile iron chill and shrinkage tendencies.

  20. Quality and sensory acceptability of a chilled functional apple ready-dessert.

    Science.gov (United States)

    Keenan, D F; Brunton, N P; Gormley, T R; Butler, F

    2012-04-01

    An apple and dairy based ready-dessert with an added prebiotic was stored and chill temperatures and number of quality attributes were monitored during chill (4 °C) storage for 30 days. All ready-desserts were thermally processed by sous vide (P (90) > 10 min). The stability of the dairy component in ready-desserts was monitored by measuring volatile free fatty acids. Changes in these components were more evident in prebiotic-enriched samples compared to controls. However, no significant differences were observed over storage in control and prebiotic-enriched ready-desserts. This was supported by sensory analysis that showed no significant changes over storage in control or prebiotic-enriched samples. Of the other quality parameters, the addition of prebiotic inclusions resulted in lower L and b values and dry matter (p < 0.05), while increasing (p < 0.05) soluble solids content compared to control samples. Fluctuations in some of the quality parameters were also observed over storage. Rheological characteristics, i.e. flow behaviour (n), consistency index (K), storage (G'), loss (G″) and complex (G*) moduli were unaffected by prebiotic inclusion. However, storage affected the rheological characteristics of ready-desserts. A decrease (p < 0.05) in flow behaviour (n) led to concomitant increases in consistency index (K) and complex modulus (G*) values in control samples. PMID:22407955

  1. SNCR - Improved control utilising modern gas analysis systems, ammonia slip retention and formation of ammonium salts in flue gas processes; SNCR - Foerbaettrad reglering genom modern gasanalysteknik, infaangning och saltbildning av ammoniakoeverskott vid roekgasrening

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Christer; Holmberg, P.; Soederbom, J.

    1996-10-01

    A key and fundamental feature of all regulating systems, including SNCR, is the collection of representative measurement parameters which reflect the changes in the process, preferably with the shortest response time possible. Effective regulating equipment, the injection system in the SNCR process, is required which must offer sufficient flexibility so that the reducing agent dosage is suited to flue gas flow, geometry of the channel, and can accommodate variations of the combustion process. The link between the injection system and the parameter signals is provided by a suitable computer algorithm which steers the process to achieve optimum performance within economic and environmental constraints. This project represents the first stage towards investigating the possibilities of improving the steering system of existing SNCR installations. The work focuses on the technical aspects associated with the measurement parameters, especially on how continual gas analysis techniques can be applied and used to regulate the process. In certain cases, gas measurements including ammonia, NH{sub 3}, are necessary in particle laden, raw flue gases (in situ measurements). The optical DOAS technique has been shown to be a suitable option for this application. A system for on-line speciation measurements of both gaseous and particle bound NH{sub 3} has been developed and proven in the field. An additional part of the project was to identify the most influential parameters affecting the process at two SNCR installations. Furthermore the degree of NH{sub 3} retention for three different types of flue gas cleaning systems has been studied. 32 refs, 39 figs, 6 tabs

  2. Thermoeconomic evaluation of air conditioning system with chilled water storage

    International Nuclear Information System (INIS)

    Highlights: • A new thermoeconomic evaluation methodology has been presented. • The relationship between thermodynamic and economic performances has been revealed. • A key point for thermal storage technology further application is discovered. • A system has been analyzed via the new method and EUD method. - Abstract: As a good load shifting technology for power grid, chilled energy storage has been paid more and more attention, but it always consumes more energy than traditional air conditioning system, and the performance analysis is mostly from the viewpoint of peak-valley power price to get cost saving. The paper presents a thermoeconomic evaluation methodology for the system with chilled energy storage, by which thermodynamic performance influence on cost saving has been revealed. And a system with chilled storage has been analyzed, which can save more than 15% of power cost with no energy consumption increment, and just certain difference between peak and valley power prices can make the technology for good economic application. The results show that difference between peak and valley power prices is not the only factor on economic performance, thermodynamic performance of the storage system is the more important factor, and too big price difference is a barrier for its application, instead of for more cost saving. All of these give a new direction for thermal storage technology application

  3. Chill-inducing music enhances altruism in humans

    Directory of Open Access Journals (Sweden)

    Hajime eFukui

    2014-10-01

    Full Text Available 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 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 (IG and the Out-group (OG, 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 Dictator Game. 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 Dictator Game 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.

  4. Chill-inducing music enhances altruism in humans.

    Science.gov (United States)

    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

  5. Ammonia concentration modeling based on retained gas sampler data

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Aquarium Nitrification Revisited: Thaumarchaeota Are the Dominant Ammonia Oxidizers in Freshwater Aquarium Biofilters

    OpenAIRE

    Sauder, Laura A; Katja Engel; Stearns, Jennifer C; Masella, Andre P; Richard Pawliszyn; Neufeld, Josh D.

    2011-01-01

    Ammonia-oxidizing archaea (AOA) outnumber ammonia-oxidizing bacteria (AOB) in many terrestrial and aquatic environments. Although nitrification is the primary function of aquarium biofilters, very few studies have investigated the microorganisms responsible for this process in aquaria. This study used quantitative real-time PCR (qPCR) to quantify the ammonia monooxygenase (amoA) and 16S rRNA genes of Bacteria and Thaumarchaeota in freshwater aquarium biofilters, in addition to assessing the d...

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

    Science.gov (United States)

    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.

  8. A Pervaporation Study of Ammonia Solutions Using Molecular Sieve Silica Membranes

    Directory of Open Access Journals (Sweden)

    Xing Yang

    2014-02-01

    Full Text Available 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.

  9. A pervaporation study of ammonia solutions using molecular sieve silica membranes.

    Science.gov (United States)

    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

  10. Ammonia removal from water: The comparison between using the wind speed and agitation method

    Directory of Open Access Journals (Sweden)

    Intamanee, J.

    2005-01-01

    Full Text Available Ammonia removal from skim latex is an essential step in skim block production process. In general, skim latex contains about 0.4% ammonia by weight of skim latex and needs to be reduced in order to minimize acid usage during rubber coagulation step. The method used to remove ammonia from skim latex in many concentrated rubber latex plants is ammonia volatilization by agitating skim latex using a large agitator in a mixing pool. In this research, a new method to remove ammonia from water by blowing wind over the water surface was investigated. The effects of agitation speed and wind speed on overall mass transfer coefficient and removal rate of ammonia were investigated in a pilot scale experiment. The result has shown that the overall mass transfer coefficient and the ammonia removal rate increase linearly with increasing Reynolds number of air and liquid. However, the ammonia removal rate by using wind speed was much higher than that given by agitation method. The wind speed method proposed in this study is then recommended for ammonia removal from skim latex. Possible ways for applying the wind speed method for skim latex production plant are also suggested. The relationship between the wind speed or Reynolds number and the mass transfer coefficient can also be used to design the system for ammonia removal from water byusing wind speed.

  11. A meta-analysis study of the effect of chilling on prevalence of Salmonella on pig carcasses.

    Science.gov (United States)

    Gonzales Barron, U; Bergin, D; Butler, F

    2008-07-01

    In the field of food safety, meta-analysis can be used to combine results of prevalence studies of pathogens at critical stages within the food processing chain so that policy makers can access reliable and concise information on the effectiveness of interventions for controlling and preventing foodborne illnesses in humans. The objective of this work was to demonstrate the applicability of a parametric approach of meta-analysis to the specific case of determining the overall effect of chilling on Salmonella prevalence on pig carcasses. A meta-analysis was performed on each of two parameters measuring effect size for binary outcomes (relative risk and risk difference). Both meta-analyses confirmed that the chilling operation has a significant beneficial effect (P pig carcasses. Because risk difference is a parameter sensitive to the differences across studies in carcass swab areas and Salmonella detection methods, its meta-analysis highly reflected this heterogeneity (P meta-analysis solution, which is deemed more suitable for compilations based on a small number of individual studies (n = 9). Because of the systematic approach of meta-analysis (i.e., individual studies are weighed according to precision) and its reliance for actual data, the output distribution of the relative risk effect size (approximately eN(-0.868,0.166)) merits consideration for inclusion in the chilling stage of quantitative risk assessments modeling the prevalence of this pathogen along the pork production chain.

  12. Ammonia disinfection of corn grains intended for ethanol fermentation

    Directory of Open Access Journals (Sweden)

    Magdalena Broda

    2009-12-01

    Full Text Available Background. Bacterial contamination is an ongoing problem for commercial bioethanol plants. It concerns factories using grain and also other raw materials for ethanol fermentation. Bacteria compete with precious yeasts for sugar substrates and micronutrients, secrete lactic and acetic acids, which are toxic for yeast and this competition leads to significant decrease of bioethanol productivity. For this study, bacterial contamination of corn grain was examined. Then the grain was treated by ammonia solution to reduce microbial pollution and after that the microbiological purity of grain was tested one more time. Disinfected and non-disinfected corn grains were ground and fermentation process was performed. Microbiological purity of this process and ethanol yield was checked out. Material and methods. The grain was disinfected by ammonia solution for two weeks. Then the grain was milled and used as a raw material for the ethanol fermentation. The fermentation process was carried out in 500-ml Erlenmeyer flasks. Samples were withdrawn for analysis at 0, 24, 48, 72 hrs. The number of total viable bacteria, lactic acid bacteria, acetic acid bacteria, anaerobic bacteria and the quantity of yeasts and moulds were signified by plate method. Results. Ammonia solution effectively reduces bacterial contamination of corn grain. Mash from grain disinfected by ammonia contains less undesirable microorganisms than mash from crude grain. Moreover, ethanol yield from disinfected grain is at the highest level. Conclusions. The ammonia solution proved to be a good disinfection agent for grain used as a raw material for bioethanol fermentation process.

  13. Global Seabird Ammonia Emissions

    Science.gov (United States)

    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

  14. Physiological and Biochemical Mechanisms of Seed Priming-Induced Chilling Tolerance in Rice Cultivars

    OpenAIRE

    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...

  15. Dormancy release and chilling requirement of buds of latitudinal ecotypes of Betula pendula and B. pubescens.

    Science.gov (United States)

    Myking, T; Heide, O M

    1995-11-01

    Bud burst and dormancy release of latitudinal ecotypes of Betula pendula Roth and B. pubescens Ehrh. from Denmark ( approximately 56 degrees N), mid-Norway ( approximately 64 degrees N) and northern Norway ( approximately 69 degrees N) were studied in controlled environments. Dormant seedlings were chilled at 0, 5 or 10 degrees C from October 4 onward and then, at monthly intervals from mid-November to February, batches of seedlings were held at 15 degrees C in an 8-h (SD) or 24-h (LD) photoperiod to permit flushing. A decline in days to bud burst occurred with increasing chilling time in all ecotypes. In November, after 44 chilling days, time to bud burst was least in plants chilled at 0 and 5 degrees C. The difference diminished with increasing chilling time, and in February, after 136 chilling days, bud burst was earliest in plants chilled at 10 degrees C. Long photoperiods during flushing significantly reduced thermal time after short chilling periods (44 and 74 days), but had no effect when the chilling requirement was fully met after 105 or more chilling days. No significant difference in these responses was found between the two species. In both species, chilling requirement decreased significantly with increasing latitude of origin. Bud burst was normal in seedlings overwintered at 12 degrees C, but was erratic and delayed in seedlings overwintered at 15 and especially at 21 degrees C, indicating that the critical overwintering temperature is between 12 and 15 degrees C. We conclude that there is little risk of a chilling deficit in birch under Scandinavian winter conditions even with a climatic warming of 7-8 degrees C. The likely effects of a climatic warming include earlier bud burst, a longer growing season and increased risk of spring frost injury, especially in high latitude ecotypes. PMID:14965987

  16. Reestablishment of ion homeostasis during chill-coma recovery in the cricket Gryllus pennsylvanicus

    OpenAIRE

    MacMillan, Heath A.; Williams, Caroline M.; Staples, James F.; Sinclair, Brent J.

    2012-01-01

    The time required to recover from cold-induced paralysis (chill-coma) is a common measure of insect cold tolerance used to test central questions in thermal biology and predict the effects of climate change on insect populations. The onset of chill-coma in the fall field cricket (Gryllus pennsylvanicus, Orthoptera: Gryllidae) is accompanied by a progressive drift of Na+ and water from the hemolymph to the gut, but the physiological mechanisms underlying recovery from chill-coma are not unders...

  17. Tolerance response to in situ ammonia stress in a pilot-scale anaerobic digestion reactor for alleviating ammonia inhibition.

    Science.gov (United States)

    Gao, Shumei; Zhao, Mingxing; Chen, Yang; Yu, Meijuan; Ruan, Wenquan

    2015-12-01

    The anaerobic digestion (AD) of protein-rich substrates is generally inhibited by ammonia. In this study, ammonia-tolerant acclimation was exposed to a stepwise in situ ammonia stress during the continuous AD of solid residual kitchen waste by using a continuous stirred tank reactor with a 50 L active volume. The reactor worked well during the acclimation process, with an average daily biogas production of 58 L/d, an effluent soluble chemical oxygen demand of 7238 mg/L, a volatile fatty acid (VFA) content of 578 mg/L, and a VFA/alkalinity ratio of less than 0.4. Moreover, ammonia stress enhanced the activity of Coenzyme F420. The results of high-throughput 16S rDNA sequencing showed that ammonia stress increased the relative abundance of Firmicutes bacteria and hydrogenotrophic methanogens but decreased the abundance of acetotrophic methanogens. This microbial community shift was proposed to be an in situ response strategy for ammonia stress adaptation.

  18. Changes of biogenic amines and quality indicators of grass carp (Ctenpharyngodon idellus) during chilled storage and effect on biogenic amines during thermal processing%草鱼冷藏过程鱼肉品质与生物胺的变化及热处理对生物胺的影响

    Institute of Scientific and Technical Information of China (English)

    张月美; 包玉龙; 罗永康; 王航

    2013-01-01

    We investigated the changes in biogenic amines and other quality indicators during chilled storage(4 ℃) and effect of thermal processing on biogenic amines (85 ℃,15 min) of grass carp (Ctenpharyngodon idellus) by observing the drip loss,sensory assessment,total volatile basic nitrogen(TVB-N),total viable counts and content of eight biogenic amines (tryptamine,2-phenylethyl-amine,putrescine,cadaverine,histamine,tyramine,spermidine and spermine).The correlation was analyzed between biogenic amines and quality indicators of grass carp.The resuhs showed that drip loss,TVB-N and total viable counts increased with storage time,which accorded with the changes of sensory scores.The preservation life of grass carp at 4 ℃ was 9 days.During the storage,putrescine and cadaverine changed most significantly that putrescine content reached (17.12 ± 4.40) mg·kg-1 and cadaverine content reached (237.47 ±3.96) mg·kg-1 at 15th day.Besides,cadaverine and putrescine had good correlation with drip loss,sensory assessment,TVB-N and total viable counts.After thermal processing,contents of putrescine,cadaverine,histamine and spermine decreased slightly,saying that thermal processing could not remove the biogenic amines of grass carp effectively.%文章研究了草鱼(Ctenpharyngodon idellus)冷藏过程鱼肉品质与生物胺的变化及热处理对生物胺的影响.将经过前处理的草鱼鱼片于4℃条件下贮藏,对其感官品质、挥发性盐基氮(TVB-N)、菌落总数、汁液流失率以及生物胺等指标进行测定,另外经过85℃、15 min的热处理后对草鱼鱼片的生物胺进行测定,探求其变化规律及草鱼的生物胺与其品质指标的相关性.结果表明,随着贮藏时间的延长,草鱼的汁液流失率、TVB-N、菌落总数均呈现明显的上升趋势,与感官分值的变化趋势相符,草鱼的感官接受极限为9d.草鱼鱼片在冷藏加工过程中变化最显著的生物胺是腐胺和尸胺,第15

  19. Tenderness of Pork Muscles as Influenced by Chilling Rate and Altered Carcass Suspension

    DEFF Research Database (Denmark)

    Kirkegaard, Elin; Møller, Anders Juel

    1987-01-01

    Evaluation of tenderness improvements in porcine muscles (longissimus dorsi, semimembranosus, biceps femoris) in 72 carcasses by using combinations of three different chilling rates and two different suspennnsion methods....

  20. Effect of processing plant on pork quality

    NARCIS (Netherlands)

    Hambrecht, E.; Eissen, J.J.; Verstegen, M.W.A.

    2003-01-01

    The impact of processing plant on pork quality was studied by assessing pork quality in three commercial plants (A, B, Q. Plants differed in the layout of the races, stunning systems (A and B: electrical, C: CO2 stunning) and chilling systems (A: rapid chilling, B and C: conventional). Factors not r

  1. Influence of pH on the kinetics of short-cut nitrification process inhibited by high concentrate ammonia%pH对高浓度氨氮短程硝化抑制动力学的影响

    Institute of Scientific and Technical Information of China (English)

    遇光禄; 喻立军; 唐颖栋

    2013-01-01

    在移动床生物膜反应器(MBBR)实现稳定短程硝化的前提下,采用模拟废水进行批式实验,研究生物膜短程硝化过程的基质抑制动力学特性及pH的影响.基于Haldane模型建立短程硝化基质抑制动力学方程,确定不同pH条件下的动力学常数.结果表明,不同pH条件下,高浓度氨氮对短程硝化的抑制特性均符合Haldane模型.pH为7.0、8.0和9.0时的氨氮最大比降解速率(qmax)分别为9.906、16.234、14.742mg/(g·h),pH=8.0是获得高效的短程硝化效果的适宜运行条件.但半亚硝化的实现则需要在氨氮降解速率适当降低的条件下(pH=7.0)才能实现.%The substrate inhibition kinetic characteristics of short-cut nitrification under different pH conditions were evaluated when the aerobic moving-bed biofilm reactor achieved a stable nitrite accumulation rate.Batch test with simulate wastewater was conducted and the kinetic equations for the different pH was established based on Haldane model.The results showed that Haldane model was able to represent the inhibitions caused by high concentrate ammonia during short-cut nitrification process under different pH.The maximal specific degrading rate (qmax) for per gram volatile suspended solids was calculated by Haldane model,when the pH value was 7.0,8.0 and 9.0,the obtained qmax was 9.906,16.234 and 14.742mg/(g·h),respectively.The pH of 8.0 was appropriate condition for short-cut nitrification,but not for the half partial nitrification.Appropriately reducing the ammonia decomposition rate could be beneficial to half partial nitrification,and pH 7.0 was the suitable condition for half partial nitrification.

  2. Enrichment and Characterization of an Autotrophic Ammonia-Oxidizing Archaeon of Mesophilic Crenarchaeal Group I.1a from an Agricultural Soil

    NARCIS (Netherlands)

    Jung, M.Y.; Park, S.J.; Min, D.; Kim, J.S.; Rijpstra, W.I.C.; Sinninghe Damsté, J.S.; Kim, G.J.; Madsen, E.L.; Rhee, S.K.

    2011-01-01

    Soil nitrification is an important process for agricultural productivity and environmental pollution. Though one cultivated representative of ammonia-oxidizing Archaea from soil has been described, additional representatives warrant characterization. We describe an ammonia-oxidizing archaeon (strain

  3. AMMONIA-FREE NOx CONTROL SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. Dark-chilling of Seedlings Affects Initiation and Morphology of Broccoli Inflorescence

    Directory of Open Access Journals (Sweden)

    Aneta GRABOWSKA

    2013-05-01

    Full Text Available The constant supply of broccoli heads for a vegetable market can be kept by the differentiation of sowing time and the age of seedlings. Dark-chilling of young seedlings can also modify the time of transplanting, subsequent plant development, yield and inflorescence quality. The aim of the present study was to analyze the influence of seedling dark-chilling on the inflorescence initiation and the morphological quality of broccoli heads. The experiment was carried out at the University of Agriculture in Krakow (South Poland in the years 2009 and 2010, with broccoli (Brassica oleracea L. var. italica Plenck medium late cultivar ‘Monaco’ F1. The examined factors were the age of seedlings (4-, 6-, 8-, and 10-week-old and dark-chilling (2°C/2 weeks and non-chilled control. Microscopic analysis of the apex sections was performed to determine the time of the inflorescence differentiation in chilled and non-chilled seedlings of different age. Chosen morphological features of the mature heads were also described as depended on age and chilling of seedlings. The inflorescence initiation was observed between 4 and 6 week of the plant ontogeny. Especially 4-week-old seedlings, chilled by two weeks, were more advanced in the generative development in comparison to non-chilled control. Low temperature applied in the seedling stage did not cause the head buttoning. Inflorescences developed by broccoli planted from 4 and 6-week-old seedlings, both chilled and control, were characterized by the best visual quality, determined by a convex head shape, tight branching angle, small and uniform size and regular form of flower buds. Chilling of oldest, 8- and 10-week-old seedlings negatively affected the inflorescence quality, through planed and spread shape of heads and non-uniform shape of flower buds.

  5. Recovery of ammonia from swine manure using gas-permeable membranes: Effect of aeration

    Science.gov (United States)

    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. Influence of ammonia on leaching behaviors of incineration fly ash and its geochemical modeling

    DEFF Research Database (Denmark)

    Astrup, Thomas Fruergaard; Guan, Zhen Zhen; Chen, De Zhen

    2013-01-01

    Incineration fly ash could be contaminated with NH3 that was slipped from the ammonia-based selective non-catalytic reduction(SNCR) process and from evaporation of municipal solid wastes' leachate involved in the wastes. This research was conducted to investigate the impacts of ammonia on leaching...

  7. Habitat-associated phylogenetic community patterns of microbial ammonia oxidizers.

    Directory of Open Access Journals (Sweden)

    Antoni Fernàndez-Guerra

    Full Text Available Microorganisms mediating ammonia oxidation play a fundamental role in the connection between biological nitrogen fixation and anaerobic nitrogen losses. Bacteria and Archaea ammonia oxidizers (AOB and AOA, respectively have colonized similar habitats worldwide. Ammonia oxidation is the rate-limiting step in nitrification, and the ammonia monooxygenase (Amo is the key enzyme involved. The molecular ecology of this process has been extensively explored by surveying the gene of the subunit A of the Amo (amoA gene. In the present study, we explored the phylogenetic community ecology of AOB and AOA, analyzing 5776 amoA gene sequences from >300 isolation sources, and clustering habitats by environmental ontologies. As a whole, phylogenetic richness was larger in AOA than in AOB, and sediments contained the highest phylogenetic richness whereas marine plankton the lowest. We also observed that freshwater ammonia oxidizers were phylogenetically richer than their marine counterparts. AOA communities were more dissimilar to each other than those of AOB, and consistent monophyletic lineages were observed for sediments, soils, and marine plankton in AOA but not in AOB. The diversification patterns showed a more constant cladogenesis through time for AOB whereas AOA apparently experienced two fast diversification events separated by a long steady-state episode. The diversification rate (γ statistic for most of the habitats indicated γ(AOA > γ(AOB. Soil and sediment experienced earlier bursts of diversification whereas habitats usually eutrophic and rich in ammonium such as wastewater and sludge showed accelerated diversification rates towards the present. Overall, this work shows for the first time a global picture of the phylogenetic community structure of both AOB and AOA assemblages following the strictest analytical standards, and provides an ecological view on the differential evolutionary paths experienced by widespread ammonia

  8. DETERMINATION OF AMMONIA IN EAR-LOBE CAPILLARY BLOOD IS AN ALTERNATIVE TO ARTERIAL BLOOD AMMONIA

    NARCIS (Netherlands)

    HUIZENGA, [No Value; GIPS, CH; CONN, HO; JANSEN, PLM

    1995-01-01

    Blood ammonia determination is a laboratory test to diagnose hepatic encephalopathy. Arterial blood is superior to peripheral venous blood ammonia because of ammonia metabolism in muscle. We have compared capillary with arterial whole blood ammonia as capillary sampling is an attractive alternative.

  9. Interannual variability of ammonia concentrations over the United States: sources and implications

    Science.gov (United States)

    Schiferl, Luke D.; Heald, Colette L.; Van Damme, Martin; Clarisse, Lieven; Clerbaux, Cathy; Coheur, Pierre-François; Nowak, John B.; Neuman, J. Andrew; Herndon, Scott C.; Roscioli, Joseph R.; Eilerman, Scott J.

    2016-09-01

    The variability of atmospheric ammonia (NH3), emitted largely from agricultural sources, is an important factor when considering how inorganic fine particulate matter (PM2.5) concentrations and nitrogen cycling are changing over the United States. This study combines new observations of ammonia concentration from the surface, aboard aircraft, and retrieved by satellite to both evaluate the simulation of ammonia in a chemical transport model (GEOS-Chem) and identify which processes control the variability of these concentrations over a 5-year period (2008-2012). We find that the model generally underrepresents the ammonia concentration near large source regions (by 26 % at surface sites) and fails to reproduce the extent of interannual variability observed at the surface during the summer (JJA). Variability in the base simulation surface ammonia concentration is dominated by meteorology (64 %) as compared to reductions in SO2 and NOx emissions imposed by regulation (32 %) over this period. Introduction of year-to-year varying ammonia emissions based on animal population, fertilizer application, and meteorologically driven volatilization does not substantially improve the model comparison with observed ammonia concentrations, and these ammonia emissions changes have little effect on the simulated ammonia concentration variability compared to those caused by the variability of meteorology and acid-precursor emissions. There is also little effect on the PM2.5 concentration due to ammonia emissions variability in the summer when gas-phase changes are favored, but variability in wintertime emissions, as well as in early spring and late fall, will have a larger impact on PM2.5 formation. This work highlights the need for continued improvement in both satellite-based and in situ ammonia measurements to better constrain the magnitude and impacts of spatial and temporal variability in ammonia concentrations.

  10. Lifa Air Secure Box method for chilled beam cleaning

    OpenAIRE

    Leppälä, Vesa-Jukka

    2014-01-01

    The objective of this Bachelor’s Thesis was to introduce a chilled beam cleaning method and to develop an improved version for the prototype introduced in 2011. This thesis was commissioned by Lifa Air Ltd. The company itself is specialized in improving Indoor Air Quality and offers a wide range of products meant for ventilation cleaning. The aim for the development work was to fill the requirements and needs set by the company based on the research done, and to construct a working and improv...

  11. Integrated Quality Assurance of Chilled Food Fish at Sea

    DEFF Research Database (Denmark)

    Frederiksen, Marco Thorup; Olsen, Karsten Bæk; Popescu, Valeriu

    1997-01-01

    The aim of the IQAS project is to improve the quality of fresh fish (white fish and flat fish) landed by the Community vessels significantly and to increase the proportion of the fish caught used for food purposes, as well as to improve the on-board working conditions. This will be achieved...... by specifying and developing safe, efficient, mechanized on-board handling systems enabling the catch to be sorted, gutted, bled, characterized for length and weight, prepared quickly and correctly for rapid chilling and to be stored in appropriate, labelled containers at 0°C until sold. A monitoring, measuring...

  12. ChillFish: A Respiration Game for Children with ADHD

    DEFF Research Database (Denmark)

    Sonne, Tobias; Jensen, Mads Møller

    2016-01-01

    Breathing exercises can help children with ADHD control their stress level, but it can be hard for a child to sustain attention throughout such an exercise. In this paper, we present ChillFish, a breath-controlled biofeedback game designed in collaboration with ADHD professionals to investigate...... and challenges of creating a tangible respiration-based controller and use it as a core game mechanic. Finally, we discuss the challenge of balancing engagement and relaxation in physically controlled games for children with ADHD in order to make a game that can be calming and still sustain their attention....

  13. Human Response to Personalized Ventilation Combined with Chilled Ceiling

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Kaczmarczyk, Jan; Marcol, Bartosz;

    2014-01-01

    , the use of radiant ceiling cooling will provide operative temperature lower than the air temperature and will improve further occupants’ thermal comfort at warm environment. Therefore combining PV with chilled ceiling may be an effective way to provide thermal comfort in rooms at temperature higher than...... period subjects’ thermal sensation ranged between warm and hot. After returning to the workstations the use of PV helped subjects to improve their thermal sensation much faster (5 min) compared to the CCMV (30 min). Air at workstation was perceived as more fresh with CCPV than with CCMV. Percentage...

  14. Chill-inducing music enhances altruism in humans

    OpenAIRE

    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 dictato...

  15. Ammonia toxicity induces glutamine accumulation, oxidative stress and immunosuppression in juvenile yellow catfish Pelteobagrus fulvidraco.

    Science.gov (United States)

    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

  16. Emergency membrane contactor based absorption system for ammonia leaks in water treatment plants

    Institute of Scientific and Technical Information of China (English)

    SHAO Jiahui; FANG Xuliang; HE Yiliang; JIN Qiang

    2008-01-01

    Because of the suspected health risks of trihalomethanes (THMs), more and more water treatment plants have replaced traditionalchlorine disinfection process with chloramines but often without the proper absorption system installed in the case of ammonia leaksin the storage room. A pilot plant membrane absorption system was developed and installed in a water treatment plant for this purpose.Experimentally determined contact angle, surface tension, and corrosion tests indicated that the sulfuric acid was the proper choice as the absorbent for leaking ammonia using polypropylene hollow fiber membrane contactor. Effects of several operating conditionson the mass transfer coefficient, ammonia absorption, and removal efficiency were examined, including the liquid concentration,liquid velocity, and feed gas concentration. Under the operation conditions investigated, the gas absorption efficiency over 99.9%was achieved. This indicated that the designed pilot plant membrane absorption system was effective to absorb the leaking ammonia in the model storage room. The removal rate of the ammonia in the model storage room was also experimentally and theoretically foundto be primarily determined by the ammonia suction flow rate from the ammonia storage room to the membrane contactor. The ammoniaremoval rate of 99.9% was expected to be achieved within 1.3 h at the ammonia gas flow rate of 500 m3/h. The success of the pilot plantmembrane absorption system developed in this study illustrated the potential of this technology for ammonia leaks in water treatmentplant, also paved the way towards a larger scale application.

  17. Ammonia effect on hydrogenotrophic methanogens and syntrophic acetate-oxidizing bacteria.

    Science.gov (United States)

    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.

  18. Tomato chilling injury threshold defined by the volatile profiles of pink harvested tomato fruit

    Science.gov (United States)

    Fresh tomato fruit show visible symptoms of chilling injury (CI) when stored at temperatures lower than the reported chilling threshold of 12.5°C. However, their sensitivity has been reported to decrease as they ripen. Volatile profiles change during ripening and are affected by physiological change...

  19. Dual roles for hepatic lectin receptors in the clearance of chilled platelets

    DEFF Research Database (Denmark)

    Rumjantseva, Viktoria; Grewal, Prabhjit K; Wandall, Hans H;

    2009-01-01

    Rapid chilling causes glycoprotein-Ib (GPIb) receptors to cluster on blood platelets. Hepatic macrophage beta(2) integrin binding to beta-N-acetylglucosamine (beta-GlcNAc) residues in the clusters leads to rapid clearance of acutely chilled platelets after transfusion. Although capping the beta-G...

  20. A chilling-resistant agent for seedling raising of early-season rice

    Institute of Scientific and Technical Information of China (English)

    JIANLingcheng; SUNLonghua

    1992-01-01

    Our lab experiments in 1986 and 1987 showed that the CR-4, a kind of chilling-sesistant agent, could obviously increase the chilling resistance of rice seedlings. The survival of seedlings was significantly higher than that of the check when located in low temperature. For example, after the seedlings were treated for 2 d at 1-0℃,

  1. Chilling Tolerance and Physiological Parameters as Influenced by Grafting in Watermelon Seedlings

    Institute of Scientific and Technical Information of China (English)

    LIU Hui-ying; ZHU Zhu-jun; LU Guo-hua; QIAN Qiong-qiu

    2003-01-01

    The influences of different rootstocks on chilling tolerance and physiological parameters in wa-termelon seedlings have been studied. The results showed that grafting improved the chilling tolerance. Com-pared with own-rooted watermelon seedlings, the grafted watermelon seedlings had lower chilling injury index,lower electrolytic leakage (%), lower malondialdehyde (MDA) content, higher chlorophyll and proline con-tent, and higher activities of superoxide dismutase (SOD), ascorbate peroxidase (AsA-POD) and de-hydroascorbate reductase (DR) in the leaves under iow temperature stress. There was a considerable differenceof chilling tolerance among different grafted watermelon seedlings due to the difference of rootstock chillingtolerance. After low temperature treatment, the grafted seedling with higher chilling tolerance had lower elec-trolytic leakage ( %), lower MDA content, higher proline content and higher activities of SOD, AsA-POD andDR in the leaves compared with the grafted seedling with weaker chilling tolerance. From these, we could con-clude that chilling tolerance of watermelon seedlings may be related to higher antioxidative ability and mem-brane stability in the plants. The chilling tolerance of grafted seedling could be properly evaluated by compre-hensive physiological indexes but not a single physiological index.

  2. Impact of personalized ventilation combined with chilled ceiling on eye irritation symptoms

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Marcol, Bartosz; Kaczmarczyk, Jan;

    2014-01-01

    , elevated air movement toward face and increased radiant cooling may have impact on the eye symptoms. Twenty four human subjects participated in experiments with PV combined with chilled ceiling system (CCPV) and with mixing ventilation (MV) combined with chilled ceiling (CCMV). In the experiments with PV...... an impact on their subjective and physiological response....

  3. Chills in Different Sensory Domains: Frisson Elicited by Acoustical, Visual, Tactile and Gustatory Stimuli

    Science.gov (United States)

    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…

  4. Tenderness of Pork Muscles as Influenced by Chilling Rate and Altered Carcass Suspension

    DEFF Research Database (Denmark)

    Kirkegaard, Elin; Møller, Anders Juel

    1987-01-01

    Evaluation of tenderness improvements in porcine muscles (longissimus dorsi, semimembranosus, biceps femoris) in 72 carcasses by using combinations of three different chilling rates and two different suspennnsion methods.......Evaluation of tenderness improvements in porcine muscles (longissimus dorsi, semimembranosus, biceps femoris) in 72 carcasses by using combinations of three different chilling rates and two different suspennnsion methods....

  5. 9 CFR 381.66 - Temperatures and chilling and freezing procedures.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Temperatures and chilling and freezing procedures. 381.66 Section 381.66 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT... Procedures § 381.66 Temperatures and chilling and freezing procedures. (a) General. Temperatures...

  6. 46 CFR 154.1760 - Liquid ammonia.

    Science.gov (United States)

    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...

  7. 27 CFR 21.96 - Ammonia, aqueous.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 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...

  8. Occurrence of Campylobacter jejuni and C. coli on broiler carcasses after chilling in southern Brazil

    Directory of Open Access Journals (Sweden)

    Gustavo Perdoncini

    2015-04-01

    Full Text Available Campylobacter jejuni and C. coli have been associated with gastrointestinal disorders in human beings, due mainly to the consumption of chicken meat. Despite control measures for reducing contamination by these bacteria, the detection of Campylobacter in carcasses after chilling remains high. A total of 105 carcasses were assessed by the horizontal detection method in five federally inspected slaughterhouses in southern Brazil in 2012 and in the first three months of 2013. Campylobacterwas isolated in 37.1% of the carcasses, of which 97.5% contained C. jejuni and 2.5% were infected by C. coli. The rate of positive carcasses across the slaughterhouses ranged from 0 to 71.4%. Determining the occurrence of Campylobacter among flocks is crucial for estimating the microbial load at specific points along the slaughtering process and for minimizing the risk of contamination of end products by Campylobacter.

  9. Forthcoming Oversupply for Synthetic Ammonia

    Institute of Scientific and Technical Information of China (English)

    Zhang Zhantong

    2007-01-01

    @@ Stable output increase The total capacity of synthetic ammonia in China is 52.0 million t/a today.There are around 540 producers mainly located in Shandong, Shanxi, Hebei,Henan, Jiangsu and Sichuan provinces.The cumulative capacity in Shandong province ranks the highest, accounting for 14.6% of the national total.

  10. Hydrogen production using ammonia borane

    Science.gov (United States)

    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.

  11. Ammonia in power plant emission

    Science.gov (United States)

    Hammerich, Mads; Henningsen, J. O.; Olafsson, Ari

    1990-08-01

    Ammonia monitoring is needed in most schemes for denitrification of power plant emission. In the PALAMON system we use a 500 MHz tunable, single mode, single line, CO2 laser as light source for a low pressure, high temperature, photoacoustic cell. With this cell we can resolve the sR(5,O) line of the ammonia spectrum, and suppress the interfering C02(9R30) absorption line down to a lppm NH3 detection limit. The validity of the measured ammonia concentrations is strongly dependent on details of the sampling system and on the reliability of the calibration routines. In particular calibration with certified mixtures of NH3:N2 has proved insufficient due to the multiple and long time constants caused by adsorption of ammonia to different materials in the system. Presence of water vapor in the gas greatly reduces these time constants. Therefore a number of methods for simple production of moist calibration gases from macroscopic amounts of NH3 are applied. The calibrations are translated to response from an easily managable absorber in order to allow automated recalibration of the photoacoustic response. Data from a field test of the system, and calibration data will be presented.

  12. 两段式冷却对牛肉食用品质的影响%Effect of two-stage chilling on eating quality of beef

    Institute of Scientific and Technical Information of China (English)

    高淑娟; 毛衍伟; 王秀江; 胡铁军; 罗欣

    2009-01-01

    The objective was to study the effect of two-stage chilling on eating quality of beef. Twenty crossbred cattle were selected (Yanbian cattle X Simmental cattle) to study the effect of two-stage chilling (TC -13--15℃ for 2 h, air velocity of 3 m/s, then changed into conventional chilling till 24 h) and conventional chilling (CC 0-4℃ for 24 h) on eating quality value of beef. The test results showed: Two-stage chilling increased the rate of the carcass temperature drop, decreased the rate of pH value drop, decreased evaporative loss of carcasses, helped to improve the color of beef, and increased shear stress, but had no significant effect on water holding capacity of beef, In the cattle slaughter process, the separate two-stage chilling treatment could decrease the tenderness of meat. With the increase of aging time, shear stress value would decrease. Electrical stimulation treatment should be combined with two-stage chilling to improve the eating quality of meat.%为探讨两段式冷却对牛肉食用品质的影响,以20头杂交牛胴体(延边牛×西门塔尔牛)按试验设计进行两段式冷却(温度-13~-15℃、时间2 h,风速3 m/s,随后转入常规冷却间至24 h)和常规冷却处理(温度0~4℃、时间24 h)相比较,研究不同处理对牛肉食用品质的影响.表明:两段式冷却处理加快胴体温度下降速率,减缓pH值下降速率,显著降低胴体冷却质量损失,使肉的色泽鲜红,提高肉的剪切力,对背最长肌的保水性无影响.可以认为在肉牛屠宰加工流程中,单独采用两段式冷却处理能降低肉的嫩度,但随时间的增加,剪切力值会有所降低,建议应用时结合电刺激处理来同时改善肉的食用品质.

  13. Power cycles with ammonia-water mixtures as working fluid

    Energy Technology Data Exchange (ETDEWEB)

    Thorin, Eva

    2000-05-01

    It is of great interest to improve the efficiency of power generating processes, i.e. to convert more of the energy in the heat source to power. This is favorable from an environmental point of view and can also be an economic advantage. To use an ammonia-water mixture instead of water as working fluid is a possible way to improve the efficiency of steam turbine processes. This thesis includes studies of power cycles with ammonia-water mixtures as working fluid utilizing different kinds of heat sources for power and heat generation. The thermophysical properties of the mixture are also studied. They play an important role in the calculations of the process performance and for the design of its components, such as heat exchangers. The studies concern thermodynamic simulations of processes in applications suitable for Swedish conditions. Available correlations for the thermophysical properties are compared and their influence on simulations and heat exchanger area predictions is investigated. Measurements of ammonia-water mixture viscosities using a vibrating wire viscometer are also described. The studies performed show that power cycles with ammonia-water mixtures as the working fluid are well suited for utilization of waste heat from industry and from gas engines. The ammonia-water power cycles can give up to 32 % more power in the industrial waste heat application and up to 54 % more power in the gas engine bottoming cycle application compared to a conventional Rankine steam cycle. However, ammonia-water power cycles in small direct-fired biomass-fueled cogeneration plants do not show better performance than a conventional Rankine steam cycle. When different correlations for the thermodynamic properties are used in simulations of a simple ammonia-water power cycle the difference in efficiency is not larger than 4 %, corresponding to about 1.3 percentage points. The differences in saturation properties between the correlations are, however, considerable at high

  14. Counteracting ammonia inhibition in anaerobic digestion by removal with a hollow fiber membrane contactor.

    Science.gov (United States)

    Lauterböck, B; Ortner, M; Haider, R; Fuchs, W

    2012-10-01

    The aim of the current study was to investigate the feasibility of membrane contactors for continuous ammonia (NH₃-N) removal in an anaerobic digestion process and to counteract ammonia inhibition. Two laboratory anaerobic digesters were fed slaughterhouse wastes with ammonium (NH₄⁺) concentrations ranging from 6 to 7.4 g/L. One reactor was used as reference reactor without any ammonia removal. In the second reactor, a hollow fiber membrane contactor module was used for continuous ammonia removal. The hollow fiber membranes were directly submerged into the digestate of the anaerobic reactor. Sulfuric acid was circulated in the lumen as an adsorbent solution. Using this set up, the NH₄⁺-N concentration in the membrane reactor was significantly reduced. Moreover the extraction of ammonia lowered the pH by 0.2 units. In combination that led to a lowering of the free NH₃-N concentration by about 70%. Ammonia inhibition in the reference reactor was observed when the concentration exceeded 6 g/L NH₄⁺-N or 1-1.2 g/L NH₃-N. In contrast, in the membrane reactor the volatile fatty acid concentration, an indicator for process stability, was much lower and a higher gas yield and better degradation was observed. The chosen approach offers an appealing technology to remove ammonia directly from media having high concentrations of solids and it can help to improve process efficiency in anaerobic digestion of ammonia rich substrates.

  15. Influence of the ventilation system on thermal comfort of the chilled panel system in heating mode

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Zhe; Ding, Yan; Wang, Shuo; Yin, Xinglei; Wang, Menglei [Tianjin University, Tianjin 300072 (China)

    2010-12-15

    In heating mode, fresh air is still essential for a chilled panel system in order to ensure the indoor air quality. In this paper, a chilled ceiling panel system was designed and built in a typical office room. The thermal environment and thermal comfort in the room were fully measured and evaluated by using the Fanger's PMV-PPD model and the standard of ISO 7730 respectively, when room was heated in two modes, one of which is the chilled panel heating mode and the other of which is the combined heating mode of chilled panel and supply air. The research results indicate that in the combined mode, ceiling ventilation improves the general thermal comfort and reduces the risk of local discomfort. Under the condition of same general thermal comfort, the heating supply upper limit of chilled panel can be increased by 12.3% because of air mixing effect caused by introduction of air ventilation. (author)

  16. Development of transport technique by chilling for melon fly, Bactrocera cucurbitae Coquillett (Diptela: Dephritidae)

    International Nuclear Information System (INIS)

    To evaluate the effect of chilling on mass-reared melon fly, Bactrocera cucurbitae COQ., groups of adult flies were exposed to 3, 0.5, -2.2 and -3.5°C for 6, 12, 24 and 48h. The recovery and longevity of adult chilled for less than 24h at about 0.5°C was not adversely affected. A special container for chilled flies, which was able to keep the temperature below 10°C for 4h, was designed for their long-distance transport. The longevities of flies using aerial distribution by helicopter and hand release on the ground using the chilled transport container were compared with direct release from an emergence box without chilling at Miyagi Island in Okinawa Prefecture. There were no significant differences in longevity between the three release methods

  17. An Inexpensive Radiosonde Chilled Mirror Sensor: An Old Technology With New Impact

    Science.gov (United States)

    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.

  18. Transcriptional Response of the Archaeal Ammonia Oxidizer Nitrosopumilus maritimus to Low and Environmentally Relevant Ammonia Concentrations

    OpenAIRE

    Nakagawa, Tatsunori; Stahl, David A.

    2013-01-01

    The ability of chemoautotrophic ammonia-oxidizing archaea to compete for ammonia among marine microorganisms at low ambient concentrations has been in part attributed to their extremely high affinity for ammonia, but as yet there is no mechanistic understanding of supporting metabolism. We examined transcription of selected genes for anabolic functions (CO2 fixation, ammonia transport, and cell wall synthesis) and a central catabolic function (ammonia oxidation) in the thaumarchaeon Nitrosopu...

  19. Fast responsive, optical trace level ammonia sensor for environmental monitoring

    Directory of Open Access Journals (Sweden)

    Abel Tobias

    2012-10-01

    Full Text Available Abstract Background Ammonia is a ubiquitous chemical substance which is created in technical and biological processes and harmful to many different organisms. One specific problem is the toxicity of ammonia in fish at levels of 25 μg/l - a very common issue in today’s aqua culture. In this study we report a development of a fast responsive, optical ammonia sensor for trace concentrations. Results Different hydrogels have been investigated as host polymers for a pH based sensing mechanism based on fluorescent dyes. A porous hydrophobic fluoropolymer membrane was used as an ion barrier cover layer to achieve a good ammonia permeability. The sensor’s sensitivity towards ammonia as well as crosssensitivity towards pH-value and salinity, and the temperature dependency have been determined. Two different methods to reference fluorescence signals have been employed to eliminate intensity-based measurement drawbacks. Conclusion The presented sensor features high sensitivity and a fast response even at concentrations near 1 ppb. No cross sensitivity towards pH and salinity could be observed and temperature dependency was determined as compensateable. Both referencing approaches prove themselves to be able to provide a simple use of the sensor for in-field applications.

  20. Amine substitution into sulfuric acid – ammonia clusters

    Directory of Open Access Journals (Sweden)

    O. Kupiainen

    2011-11-01

    Full Text Available The substitution of ammonia by dimethylamine in sulfuric acid – ammonia – dimethylamine clusters was studied using a collision and evaporation dynamics model. Quantum chemical formation free energies were computed using B3LYP/CBSB7 for geometries and frequencies and RI-CC2/aug-cc-pV(T+dZ for electronic energies. We first demonstrate the good performance of our method by a comparison with an experimental study investigating base substitution in positively charged clusters, and then continue by simulating base exchange in neutral clusters, which cannot be measured directly. Collisions of a dimethylamine molecule with an ammonia containing positively charged cluster result in the instantaneous evaporation of an ammonia molecule, while the dimethylamine molecule remains in the cluster. According to our simulations, a similar base exchange can take place in neutral clusters, although the overall process is more complicated. Neutral sulfuric acid – ammonia clusters are significantly less stable than their positively charged counterparts, resulting in a competition between cluster evaporation and base exchange.

  1. Ammonia modification of oxide-free Si(111) surfaces

    Science.gov (United States)

    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.

  2. Effects of Aesthetic Chills on a Cardiac Signature of Emotionality.

    Directory of Open Access Journals (Sweden)

    Maria Sumpf

    Full Text Available 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.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.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.

  3. Effects of Aesthetic Chills on a Cardiac Signature of Emotionality

    Science.gov (United States)

    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

  4. A Zinc Oxide Nanorod Ammonia Microsensor Integrated with a Readout Circuit on-a-Chip

    Directory of Open Access Journals (Sweden)

    Chyan-Chyi Wu

    2011-11-01

    Full Text Available A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.35 mm complementary metal oxide semiconductor (CMOS process was investigated. The structure of the ammonia sensor is composed of a sensitive film and polysilicon electrodes. The ammonia sensor requires a post-process to etch the sacrificial layer, and to coat the sensitive film on the polysilicon electrodes. The sensitive film that is prepared by a hydrothermal method is made of zinc oxide. The sensor resistance changes when the sensitive film adsorbs or desorbs ammonia gas. The readout circuit is used to convert the sensor resistance into the voltage output. Experiments show that the ammonia sensor has a sensitivity of about 1.5 mV/ppm at room temperature.

  5. A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip.

    Science.gov (United States)

    Yang, Ming-Zhi; Dai, Ching-Liang; Wu, Chyan-Chyi

    2011-01-01

    A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process was investigated. The structure of the ammonia sensor is composed of a sensitive film and polysilicon electrodes. The ammonia sensor requires a post-process to etch the sacrificial layer, and to coat the sensitive film on the polysilicon electrodes. The sensitive film that is prepared by a hydrothermal method is made of zinc oxide. The sensor resistance changes when the sensitive film adsorbs or desorbs ammonia gas. The readout circuit is used to convert the sensor resistance into the voltage output. Experiments show that the ammonia sensor has a sensitivity of about 1.5 mV/ppm at room temperature.

  6. A Zinc Oxide Nanorod Ammonia Microsensor Integrated with a Readout Circuit on-a-Chip

    Science.gov (United States)

    Yang, Ming-Zhi; Dai, Ching-Liang; Wu, Chyan-Chyi

    2011-01-01

    A zinc oxide nanorod ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.35 μm complementary metal oxide semiconductor (CMOS) process was investigated. The structure of the ammonia sensor is composed of a sensitive film and polysilicon electrodes. The ammonia sensor requires a post-process to etch the sacrificial layer, and to coat the sensitive film on the polysilicon electrodes. The sensitive film that is prepared by a hydrothermal method is made of zinc oxide. The sensor resistance changes when the sensitive film adsorbs or desorbs ammonia gas. The readout circuit is used to convert the sensor resistance into the voltage output. Experiments show that the ammonia sensor has a sensitivity of about 1.5 mV/ppm at room temperature. PMID:22247656

  7. Efficiency of deodorant materials for ammonia reduction in indoor air

    DEFF Research Database (Denmark)

    Bivolarova, Mariya Petrova; Mizutani, Chiyomi; Melikov, Arsen Krikor;

    2014-01-01

    A comparative study about the removability of ammonia gas in the air by activated carbon fiber (ACF) felt chemically treated with acid and a cotton fabric processed with iron phthalocyanine with copper (Cu) was performed in small-scale experiments. The test rig consisted of a heated plate and its...... proved activated carbon fiber felt with acid to be highly efficient in removing ammonia gas. Air temperature did not have profound effect on ACF performance. However, efficiency of the carbon fiber felt decreased when relative humidity was raised from 20 to 80%....

  8. Effects of liquid ammonia treatment on the physical properties of knit fabric

    Science.gov (United States)

    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.

  9. Growth of ammonia-oxidizing archaea and bacteria in cattle manure compost under various temperatures and ammonia concentrations.

    Science.gov (United States)

    Oishi, Ryu; Tada, Chika; Asano, Ryoki; Yamamoto, Nozomi; Suyama, Yoshihisa; Nakai, Yutaka

    2012-05-01

    A recent study showed that ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) coexist in the process of cattle manure composting. To investigate their physiological characteristics, liquid cultures seeded with fermenting cattle manure compost were incubated at various temperatures (37°C, 46°C, or 60°C) and ammonium concentrations (0.5, 1, 4, or 10 mM NH (4) (+) -N). The growth rates of the AOB and AOA were monitored using real-time polymerase chain reaction analysis targeting the bacterial and archaeal ammonia monooxygenase subunit A genes. AOB grew at 37°C and 4 or 10 mM NH (4) (+) -N, whereas AOA grew at 46°C and 10 mM NH (4) (+) -N. Incubation with allylthiourea indicated that the AOB and AOA grew by oxidizing ammonia. Denaturing gradient gel electrophoresis and subsequent sequencing analyses revealed that a bacterium related to Nitrosomonas halophila and an archaeon related to Candidatus Nitrososphaera gargensis were the predominant AOB and AOA, respectively, in the seed compost and in cultures after incubation. This is the first report to demonstrate that the predominant AOA in cattle manure compost can grow and can probably oxidize ammonia under moderately thermophilic conditions.

  10. Nitrate to ammonia ceramic (NAC) bench scale stabilization study

    Energy Technology Data Exchange (ETDEWEB)

    Caime, W.J.; Hoeffner, S.L. [RUST - Clemson Technical Center, Anderson, SC (United States)

    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.

  11. Ammonia recovery from livestock waste using gas permeable membrane technology

    Science.gov (United States)

    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...

  12. Electrochemically driven extraction and recovery of ammonia from human urine.

    Science.gov (United States)

    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.

  13. Ammonia for hydrogen storage: challenges and opportunities

    DEFF Research Database (Denmark)

    Klerke, Asbjørn; Christensen, Claus H.; Nørskov, Jens Kehlet;

    2008-01-01

    The possibility of using ammonia as a hydrogen carrier is discussed. Compared to other hydrogen storage materials, ammonia has the advantages of a high hydrogen density, a well-developed technology for synthesis and distribution, and easy catalytic decomposition. Compared to hydrocarbons...... and alcohols, it has the advantage that there is no CO2 emission at the end user. The drawbacks are mainly the toxicity of liquid ammonia and the problems related to trace amounts of ammonia in the hydrogen after decomposition. Storage of ammonia in metal ammine salts is discussed, and it is shown...... that this maintains the high volumetric hydrogen density while alleviating the problems of handling the ammonia. Some of the remaining challenges for research in ammonia as a hydrogen carrier are outlined....

  14. Bioaugmentation as a solution to increase methane production from an ammonia-rich substrate.

    Science.gov (United States)

    Fotidis, Ioannis A; Wang, Han; Fiedel, Nicolai R; Luo, Gang; Karakashev, Dimitar B; Angelidaki, Irini

    2014-07-01

    Ammonia-rich substrates inhibit the anaerobic digestion (AD) process and constitute the main reason for low energy recovery in full-scale reactors. It is estimated that many full-scale AD reactors are operating in ammonia induced "inhibited steady-state" with significant losses of the potential biogas production yield. To date there are not any reliable methods to alleviate the ammonia toxicity effect or to efficiently digest ammonia-rich waste. In the current study, bioaugmentation as a possible method to alleviate ammonia toxicity effect in a mesophilic continuously stirred-tank reactor (CSTR) operating under "inhibited steady state" was tested. A fast growing hydrogenotrophic methanogen (i.e., Methanoculleus bourgensis MS2(T)) was bioaugmented in the CSTR reactor at high ammonia levels (5 g NH4(+)-N L(-1)). A second CSTR reactor was used as control with no bioaugmentation. The results derived from this study clearly demonstrated a 31.3% increase in methane production yield in the CSTR reactor, at steady-state, after bioaugmentation. Additionally, high-throughput 16S rRNA gene sequencing analysis showed a 5-fold increase in relative abundance of Methanoculleus spp. after bioaugmentation. On the contrary to all methods used today to alleviate ammonia toxicity effect, the tested bioaugmentation process performed without interrupting the continuous operation of the reactor and without replacing the ammonia-rich feedstock.

  15. Use of Ultraviolet Light for the Inactivation of Listeria monocytogenes and Lactic Acid Bacteria Species in Recycled Chill Brines

    OpenAIRE

    Gailunas, Karol Marie

    2003-01-01

    Ready-to-eat meat products have been implicated in several foodborne listeriosis outbreaks. Microbial contamination of these products can occur after the product has been thermally processed and is being rapidly chilled using salt brines. The objective of this study was to determine the effect of ultraviolet irradiation on the inactivation of Listeria monocytogenes and lactic acid bacteria in a model brine chiller system. Two concentrations of brines (7.9%w/w or 13.2%w/w) were inoculated w...

  16. Effect of low frequency electromagnetic field on microstructures and macrosegregation of horizontal direct chill casting aluminum alloy

    Institute of Scientific and Technical Information of China (English)

    赵志浩; 崔建忠; 董杰; 张海涛; 张北江

    2004-01-01

    The influences of low frequency electromagnetic field on cast surface, microstructures and macrosegregation in horizontal direct chill(HDC) casting process were investigated experimentally. The cast surfaces, microstructures and macrosegregation of the ingots manufactured by conventional HDC and low frequency electromagnetic HDC casting were compared. The results show that low frequency electromagnetic field significantly improves the surface quality, refines the microstructures and reduces macrosegregation. Further more, increasing electromagnetic intensity or decreasing frequency is beneficial to the improvement. In the range of ampere-turns and frequency employed in the experiments, the optimum ampere-turns is found to be 10 000 A · turn and the frequency to be 30 Hz.

  17. Ammonia-oxidising archaea--physiology, ecology and evolution.

    Science.gov (United States)

    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

  18. Nitrification resilience and community dynamics of ammonia-oxidizing bacteria with respect to ammonia loading shock in a nitrification reactor treating steel wastewater.

    Science.gov (United States)

    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

  19. Cerebroside C increases tolerance to chilling injury and alters lipid composition in wheat roots.

    Directory of Open Access Journals (Sweden)

    Hong-Xia Li

    Full Text Available 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.

  20. Reduction of Chilling Injury and Ultrastructural Damage in Cherry Tomato Fruits After Hot Water Treatment

    Institute of Scientific and Technical Information of China (English)

    YANG Jing; FU Mao-run; ZHAO Yu-ying; MAO Lin-chun

    2009-01-01

    The effects of hot water treatment in alleviating chilling injury and reducing ultrastructural damage of mature-green cherry tomatoes (Lycopersicun esculentum cv. cerasiform Alef) were investigated. Mature-green cherry tomato fruits were treated in water at 40℃ or 45℃ for 5 rain or 15 rain, and then stored at 5℃ for 19 days followed by ripening at 20℃. Water treatment at 40℃ for 15 rain increased tolerance of cherry tomato fruits to chilling stress, indicating as low outbreak of skin lesion, high color a* value, and low electrolyte leakage. Treated fi'uits showed typical climacteric respiration and developed normal red color with chlorophyll degradation and lyeopene accumulation during ripening, while fruits without treatment failed to develop red color and suffered skin lesion. After 19 days of chilling, heated fruits showed the conversion of chloroplast to ehromoplast with the disappearance of thylakoids. Mitochondria and other cell organelles were not adversely affected in treated fruits. However, ultrastruetures in periearp cells in control fruits severely damaged with extensive disorganization of cytoplasm, swelled chloroplasts, distorted and unstacked thylakoids. Chloroplast was the first and most severely impacted organelle by chilling stress. Hot water treatment (40℃ for 15 min) before storage alleviated chilling injury in cherry tomato fruits. The results suggest that chilling injury is related with the damage of cell structure under chilling stress.

  1. Effects of Short-Term Chilling Stress on the Photosystems and Chloroplast Ultrastructure in Sweet Pepper

    Institute of Scientific and Technical Information of China (English)

    LI Xin-guo; BI Yu-ping; ZHAO Shi-jie; MENG Qing-wei; HE Qi-wei; ZOU Qi

    2005-01-01

    By measuring chlorophyll fluorescence parameters, composition of fatty acids, active oxygen species and activities of some antioxidant enzymes, effects of chilling stress (4℃) in the low light (100 μmol m-2 s-1) on chilling-sensitive plants were studied. After 6 h chilling stress (4℃) in the low light, the maximal photochemical efficiency of PSⅡ (Fv/Fm) of sweet pepper leaves decreased by 35.6%, and the oxidizable P700 decreased by 60%. However, chilling stress in the dark had no effect on both of them. Unsaturation of fatty acids in thylakoid membrane was accelerated, which might be helpful to stabilize photosynthetic apparatus. Distortion and swelling of grana caused by chilling in the dark probably decreased activities of antioxidant enzymes, which resulted in the accumulation of active oxygen species. On the contrary,photooxidation might be related to the disintegration and unstacking of grana. Chilling stress induced photoinhibition of PSⅡ and PSⅠ, and active oxygen species might be one of the factors causing the decrease of the oxidizable P700. PSⅠseemed to be more sensitive to chilling stress in the low light than PSⅡ.

  2. Music chills: The eye pupil as a mirror to music's soul.

    Science.gov (United States)

    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.

  3. Music chills: The eye pupil as a mirror to music's soul.

    Science.gov (United States)

    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. Ammonia abatement by slurry acidification

    DEFF Research Database (Denmark)

    Petersen, Søren O.; Hutchings, Nicholas John; Hafner, Sasha;

    2016-01-01

    Livestock production systems can be major sources of trace gases including ammonia (NH3), the greenhouse gases methane (CH4) and nitrous oxide (N2O), and odorous compounds such as hydrogen sulphide (H2S). Short-term campaigns have indicated that acidification of livestock slurry during in...... generally high. It was concluded that the contribution from floors to NH3 emissions was effect on N2O emissions was observed. The effect...

  5. Ammonia Production, Excretion, Toxicity, and Defense in Fish: A Review

    OpenAIRE

    Yuen K Ip; Chew, Shit F.

    2010-01-01

    Many fishes are ammonotelic but some species can detoxify ammonia to glutamine or urea. Certain fish species can accumulate high levels of ammonia in the brain or defense against ammonia toxicity by enhancing the effectiveness of ammonia excretion through active NH 4 + transport, manipulation of ambient pH, or reduction in ammonia permeability through the branchial and cutaneous epithelia. Recent reports on ammonia toxicity in mammalian brain reveal the importance of permeation of ammonia thr...

  6. Fiber-Optic Ammonia Sensors

    Science.gov (United States)

    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

  7. Planar waveguide sensor of ammonia

    Science.gov (United States)

    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. A comparison of chilled DI water/ozone and CO{sub 2}-based supercritical fluids as replacements for photoresist-stripping solvents

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, J.B.; Davenhall, L.B.; Barton, J.; Taylor, C.M.V. [Los Alamos National Lab., NM (United States). Chemical Science and Technology Div.; Tiefert, K. [Hewlett-Packard Co., Santa Clara, CA (United States)

    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.

  9. Synthesis of hydrides by interaction of intermetallic compounds with ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Tarasov, Boris P., E-mail: tarasov@icp.ac.ru [Institute of Problems of Chemical Physics of the Russian Academy of Sciences, Chernogolovka 142432 (Russian Federation); Fokin, Valentin N.; Fokina, Evelina E. [Institute of Problems of Chemical Physics of the Russian Academy of Sciences, Chernogolovka 142432 (Russian Federation); Yartys, Volodymyr A., E-mail: volodymyr.yartys@ife.no [Institute for Energy Technology, Kjeller NO 2027 (Norway); Department of Materials Science and Engineering, Norwegian University of Science and Technology, Trondheim NO 7491 (Norway)

    2015-10-05

    Highlights: • Interaction of the intermetallics A{sub 2}B, AB, AB{sub 2}, AB{sub 5} and A{sub 2}B{sub 17} with NH{sub 3} was studied. • The mechanism of interaction of the alloys with ammonia is temperature-dependent. • Hydrides, hydridonitrides, disproportionation products or metal–N–H compounds are formed. • NH{sub 4}Cl was used as an activator of the reaction between ammonia and intermetallics. • Interaction with ammonia results in the synthesis of the nanopowders. - Abstract: Interaction of intermetallic compounds with ammonia was studied as a processing route to synthesize hydrides and hydridonitrides of intermetallic compounds having various stoichiometries and types of crystal structures, including A{sub 2}B, AB, AB{sub 2}, AB{sub 5} and A{sub 2}B{sub 17} (A = Mg, Ti, Zr, Sc, Nd, Sm; B = transition metals, including Fe, Co, Ni, Ti and nontransition elements, Al and B). In presence of NH{sub 4}Cl used as an activator of the reaction between ammonia and intermetallic alloys, their interaction proceeds at rather mild P–T conditions, at temperatures 100–200 °C and at pressures of 0.6–0.8 MPa. The mechanism of interaction of the alloys with ammonia appears to be temperature-dependent and, following a rise of the interaction temperature, it leads to the formation of interstitial hydrides; interstitial hydridonitrides; disproportionation products (binary hydride; new intermetallic hydrides and binary nitrides) or new metal–nitrogen–hydrogen compounds like magnesium amide Mg(NH{sub 2}){sub 2}. The interaction results in the synthesis of the nanopowders where hydrogen and nitrogen atoms become incorporated into the crystal lattices of the intermetallic alloys. The nitrogenated materials have the smallest particle size, down to 40 nm, and a specific surface area close to 20 m{sup 2}/g.

  10. Application of PTFE membrane for ammonia removal in a membrane contactor.

    Science.gov (United States)

    Ahn, Y T; Hwang, Y H; Shin, H S

    2011-01-01

    The feasibility of a membrane contactor system for ammonia removal was studied. The mass transfer coefficient was used to quantitatively compare the effect of various operation conditions on ammonia removal efficiency. Effective removal of ammonia was possible with a Polytetrafluoroethylene (PTFE) membrane contactor system at all tested conditions. Among the various operation parameters, contact time and solution pH showed significant effect on the ammonia removal mechanism. The overall ammonia removal rate was not affected by influent suspended solution concentration unlike other pressure driven membrane filtration processes. Also the osmotic distillation phenomena which deteriorate the mass transfer efficiency can be minimized by preheating of influent wastewater. A membrane contactor system can be a possible alternative to treat high strength nitrogen wastewater by optimizing operation conditions such as stripping solution flow rate, influent wastewater temperature, and influent pH.

  11. pH-dependent ammonia removal pathways in microbial fuel cell system.

    Science.gov (United States)

    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

  12. Physiological and Biochemical Mechanisms of Seed Priming-Induced Chilling Tolerance in Rice Cultivars.

    Science.gov (United States)

    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

  13. "On-off" thermoresponsive coating agent containing salicylic acid applied to maize seeds for chilling tolerance.

    Directory of Open Access Journals (Sweden)

    Yajing Guan

    Full Text Available 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.

  14. "On-off" thermoresponsive coating agent containing salicylic acid applied to maize seeds for chilling tolerance.

    Science.gov (United States)

    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

  15. Physiological and biochemical mechanisms of seed priming-induced chilling tolerance in rice cultivars

    Directory of Open Access Journals (Sweden)

    Saddam eHussain

    2016-02-01

    Full Text Available 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.

  16. Simple model for the prediction of ammonia volatilization from water basin: effect of water temperature and pH

    Directory of Open Access Journals (Sweden)

    Intamanee, J.

    2004-03-01

    Full Text Available Ammonia is a primary chemical used for preserving rubber latex. Consequently, the wastewater from concentrated rubber latex processing contains high ammonia concentration. The volatilization of ammonia from such wastewater may cause an air pollution problem such as the formation of an acid rain or an aerosol of ammonium nitrate and ammonium sulfate, which can seriously affect environment and human being. To assess the air pollution problem regarding atmospheric ammonia volatized from wastewater, the model for the prediction of ammonia volatilization rate and flux is therefore desirable. The purposes of this study were to investigate the effects of water temperature and pH on ammonia volatilization process and to develop a model to describe ammonia volatilization rate and flux including such effects.Ammonia volatilization from water was studied by using a volatilization tank (surface area = 780 cm2, volume = 7 L placed in a water bath in order to control the water temperature. The temperature and pH in the range of 25 to 50ºC and 5 to 11 were respectively investigated. The overall mass transfer coefficients of ammonia were measured as a function of temperature and pH. The quadratic multiple regression technique was used to obtain the model for mass transfer coefficient from experimental data. The model suggests that the overall mass transfer coefficient of ammonia increases with increasing water temperature and pH while the temperature-pH interaction retards the increasing characteristic of mass transfer coefficient. Thus the increasing in mass transfer coefficient at higher temperature and pH was slower than that at the lower one. The simple model for the prediction of ammonia volatilization rate and flux was developed based on mass transfer theory and mass transfer coefficient model obtained from this study. This simple ammonia emission model can be used to predict ammonia volatilization rate and flux at any pH, water temperature and

  17. Enhanced electrokinetic remediation of fluorine-contaminated soil by applying an ammonia continuous circulation system

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Shufa; Zhou, Ming; Zhang, Shuangyan [Henan University of Science and Technology, Luoyang (China)

    2016-02-15

    The objective of this research was to investigate the effects of ammonia continuous circulation enhanced electrokinetic remediation of fluorine contaminated soil and to analyze its influence on soil pH after remediation. An experimental study was carried out in self-made electrokinetic apparatus. The voltage gradient was set at 1.0V/cm and ammonia water with different concentrations was used as electrolyte which circulated in series. Comparative studies were made by using deionized water as electrolyte which circulated separately in one experiment and continuously in another. According to the experiment the continuous circulation of ammonia water increased the current value during the remediation process and maintained current through the soil cell stabler, which not only increased fluorine migration but also reduced energy consumption. Among the given ammonia concentrations (0, 0.01, 0.1 and 0.2mol/L) the removal rate increased with ammonia concentration. 0.2mol/L had the highest current (26.8mA), and the removal rate amounted up to 57.3%. By using ammonia circulation enhanced electrokinetic technology, the difference between pH values of cathode soil and anode soil became smaller. Ammonia continuous circulation enhanced electrokinetics can effectively remediate fluorine contaminated soil and the residual ammonia in the soil can also improve soil fertility.

  18. Ammonia-a refrigerant in the past and present, more and more in the future

    International Nuclear Information System (INIS)

    The harmful influence on the global climate of CFCs (R11, R12, R502) and HCFCs (R22) refrigerants causes the depletion of the stratospheric ozone and the greenhouse effect. The international activity for the phase-out of the ozone depletion substances (ODSS) is the Montreal Protocol. The alternative refrigerants on the market are natural working fluids: ammonia, hydrocarbons (HCs), carbon dioxide, water and air. HFCs are for some applications the alternatives for CFC/HCFCs and have no ozone depletion (ODP=O), but the HFCs are greenhouse gases and have GWP and are regulated in the Kyoto Protocol. Ammonia has been in use for more than 125 years. The advantages of ammonia are excellent thermodynamic and heat transport properties, but ammonia is regarded as toxic and flammable. The ammonia refrigerating systems are liable under codes and standards, which shall be followed. With better knowledge and understanding, good practice and right comprehension of people involved in ammonia refrigeration, this refrigerant is a winner. There are many research projects and activities in order to widen the use of ammonia in the applications where CFC/HCFCs were used in the past. Regarding to this trend, it is a paradoxical situation in Macedonia and other developing countries where ammonia systems of cold stores, diaries, breweries and food processing go out of use. (Author)

  19. Application of HACCP in Production of Chilled Meat%HACCP体系在冷却肉生产中的应用

    Institute of Scientific and Technical Information of China (English)

    刘娟

    2012-01-01

    介绍了HACCP体系及其在肉制品中的应用现状,并阐述了HACCP质量管理体系在冷却肉生产加工过程中的应用.%This paper introduced the HACCP system and its application status in meat product, and then expounded the application of HACCP quality management system in the processing of chilled pork.

  20. Integrated Quality Assurance of Chilled Food Fish at Sea

    DEFF Research Database (Denmark)

    Frederiksen, Marco Thorup; Olsen, Karsten Bæk; Popescu, Valeriu

    1997-01-01

    The aim of the IQAS project is to improve the quality of fresh fish (white fish and flat fish) landed by the Community vessels significantly and to increase the proportion of the fish caught used for food purposes, as well as to improve the on-board working conditions. This will be achieved by......, container labelling and data storage system has been developed to specify the quality of the fish to the buyer at the point of sale by reference to the actual time/temperature history of the fish prior to the sale and to the measurements of length and weight...... specifying and developing safe, efficient, mechanized on-board handling systems enabling the catch to be sorted, gutted, bled, characterized for length and weight, prepared quickly and correctly for rapid chilling and to be stored in appropriate, labelled containers at 0°C until sold. A monitoring, measuring...

  1. Respiratory Response of Dormant Nectarine Floral Buds on Chilling Deficiency

    Institute of Scientific and Technical Information of China (English)

    TAN Yue; GAO Dong-sheng; LI Ling; CHEN Xiu-de; XU Ai-hong

    2010-01-01

    Changes in main biochemical respiratory pathways in dormant nectarine floral buds were studied with nectarine trees (Prunus persica.var,nectariana cv.Shuguang) in order to determine the function of respiration in dormancy release.Oxygen-electrode system and respiratory inhibitors were used to measure total respiratory rates and rates of respiratory pathways.Results showed that chilling deficiency blocked the transition of respiratory mode,and made buds stay in a state of high level pentose phosphate pathway (PPP) and low level tricarboxylic acid cycle (TCA).The decline of PPP and activation of TCA occurred synchronously with the release of dormancy.In addition,the inhibition of PPP stimulated a respiration increase related with TCA.It could be concluded that the function of PPP activation in dormancy release might be limited and PPP declination inducing TCA activation might be part of respiration mode transition mechanism during bud sprouting.

  2. Two-Pipe Chilled Beam System for Both Cooling and Heating of Office Buildings

    OpenAIRE

    Afshari, Alireza; Gordnorouzi, Rouzbeh; Hultmark, Göran; Bergsøe, Niels Christian

    2013-01-01

    Simulations were performed to compare a conventional 4-pipe chilled beam system and a 2-pipe chilled beam system. The objective was to establish requirements, possibilities and limitations for a well-functioning 2-pipe chilled beam system for both cooling and heating of office buildings. The building model had a net volume of 3669 m3, (L*B: 25.5m*11.5 m) and net ceiling height of 2.55 m. The building model was assumed to consist of 78 office rooms, 6 meeting rooms and 5 corridors with a 50% o...

  3. Analysis and Evaluation Indicator Selection of Chilling Tolerance of Different Cotton Genotypes

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objectivc] This study aimed to investigate the chilling tolerance of seedlings of different cotton genotypes and screen appropriate indicators for assess- ing chilling tolerance, to establish reliable mathematical evaluation model for chilling tolerance of cotton, thus providing theoretical basis for breeding and promoting new chilling-tolerant cotton germplasms and large-scale evaluation of chilling tolerance of cotton varieties. [Method] Fifteen cotton varieties (lines) were used as experimental materials. The photosynthetic gas exchange parameters, chlorophyll fluorescence ki- netic parameters, chlorophyll content, relative soluble sugar content, malonaldehyde content, relative proiine content, relative conductivity and other 12 physiological indi- cators of seedling leaves under low temperature treatment (5 ℃, 12 h) and recovery treatment (25 ℃. 24 h) were determined; based on the chilling tolerance coefficient (CTC) of various individual indicators, the comprehensive evaluation of chilling toler- ance was conducled by using principal component analysis, hierarchical cluster anal- ysis and stepwise regression analysis. [Result] The results showed that the 12 indi- vidual physiological indicators could be classified into 7 independent comprehensive components by principal component analysis; 15 cotton varieties (lines) were clus- tered into three categories by using membership function method and hierarchical cluster analysis; the mathematical model for evaluating chilling tolerance of cotton seedlings was established: D =0.275 -0.244Fo1 +0.206Fv/Fm1+0.326g,%-0.056SS + 0.225MDA+O.O38REC (FF=0.995), and the evaluation accuracy of the equation was higher than 94.25%,0. Six identification indicators closely related to chilling tolerance were screened, including Fo,, Fv/Fm1, Seedling leaves of cotton varieties (lines) gs2, SS, MDA, and REC. [Conclusion] with high chilling tolerance are less dam- aged under low temperature stress, and are able to maintain

  4. Prediction of Pressure Drop in Chilled Water Piping System Using Theoretical and CFD Analysis

    Directory of Open Access Journals (Sweden)

    Shirish P. Patil

    2013-08-01

    Full Text Available In the present study, three dimensional models of chilled water piping system is created using design modeler of Ansys-13. Ansys-13 fluent is used to analyses flow through chilled water pipe for pressure drop prediction. Karman-Prandtl equation is used for defining velocity profile of turbulent flow with the help of user defined function. Result obtained from CFD analysis is compared with results of 3K, 2K, ISHARE and Carrier equivalent length methods. Statistical analysis of performance based relative error has been carried out and based on that optimum analytical method for pressure drop prediction in chilled water piping is suggested.

  5. 火电厂氨法烟气脱硫装置运行参数检测与控制系统设计%Operation Parameters Detection and Control System Design for Ammonia-based Flue Gas Desulfurization Process of Thermal Power Plant

    Institute of Scientific and Technical Information of China (English)

    徐澎波; 何仁初; 赵立华

    2011-01-01

    大型氨法烟气脱硫(FGD)作为一项新的环保技术,其装置几乎涉及了所有的化工操作单元,对工艺及控制也提出了很高的要求.本文以国内首套某电厂2×300MW机组氨法烟气脱硫装置为例,设计了一套氨法烟气脱硫系统运行参数检测及控制系统,使得装置操作更加安全平稳,有效的降低了氨耗并且改善了副产品质量,在满足环保要求的同时使氨法脱硫装置能经济有效地运行.%Large scale ammonia-based FGD is a new environmental protection technology almost including all chemical engineering operation units. This type equipment is very strict on process and control system. In this paper, taking the first control project with 2×300MW units ammonia-based FGD in a domestic thermal power plant as an example, an operation parameters detection and control system is designed according to the FGD technical requirements. This control system can make the equipment run stably and reducing ammonia consumption greatly with improving by-product quality, and this ammonia-based FGD equipment can run economically and effectively base on the meeting the requirements of environmental protection.

  6. Inhibition of Direct Electrolytic Ammonia Oxidation Due to a Change in Local pH

    International Nuclear Information System (INIS)

    Electrochemical ammonia oxidation has gained a lot of attention recently as an efficient method for ammonia removal from wastewater, for the use in ammonia-based fuel cells and the production of high purity hydrogen. Thermally decomposed iridium oxide films (TDIROF) have been shown to be catalytically active for direct ammonia oxidation in aqueous solutions if NH3 is present. However, the process was reported to be rapidly inhibited on TDIROF. Herein, we show that this fast inhibition of direct ammonia oxidation does not result from surface poisoning by adsorbed elemental nitrogen (Nads). Instead, we propose that direct ammonia oxidation and oxygen evolution can lead to a drop of the local pH at the electrode resulting in a low availability of the actual reactant, NH3. The hypothesis was tested with cyclic voltammetry (CV) experiments on stagnant and rotating disk electrodes (RDE). The CV experiments on the stagnant electrode revealed that the decrease of the ammonia oxidation peaks was considerably reduced by introducing an idle phase at open circuit potential between subsequent scans. Furthermore, the polarization of the TDIROF electrode into the hydrogen evolution region (HER) resulted in increased ammonia oxidation peaks in the following anodic scans which can be explained with an increased local pH after the consumption of protons in the HER. On the RDE, the ammonia oxidation peaks did not decrease in immediately consecutive scans. These findings would not be expected if surface poisoning was responsible for the fast inhibition but they are in good agreement with the proposed mechanism of pH induced limitation by the reactant, NH3. The plausibility of the mechanism was also supported by our numerical simulations of the processes in the Nernstian diffusion layer. The knowledge about this inhibition mechanism of direct ammonia oxidation is especially important for the design of electrochemical cells for wastewater treatment. The mechanism is not only valid for

  7. Microbial quality of industrial liquid egg white: assumptions on spoiling issues in egg-based chilled desserts.

    Science.gov (United States)

    Techer, Clarisse; Daoud, Amina; Madec, Marie-Noëlle; Gautier, Michel; Jan, Sophie; Baron, Florence

    2015-02-01

    As a 1st step, this study aimed at investigating the microbial quality of liquid egg white in a French egg processing company. Thirty raw and 33 pasteurized liquid egg white samples were analyzed. Pasteurization was globally found efficient on mesophilic contaminants (1.7 ± 1.6 and 0.8 ± 0.9 log CFU/mL in raw and pasteurized samples, respectively), including for the control of Salmonella. However, Gram-positive enterococci were still detected in the pasteurized samples. As a 2nd step, a representative bacterial collection was built for exploring the spoilage issue in egg-based chilled desserts. Custard cream was chosen as growth medium since this food is widely used for the production of French chilled desserts. All of the 166 isolates of the bacterial collection were shown to be able to grow and to induce spoilage of the custard cream at refrigeration temperature (10 °C). Several spoilage types were highlighted in the custard cream, on the basis of changes regarding pH, consistency, production of holes or gas. As a 3rd step, bacterial enzymatic activities were explored on custard cream-based agar media. The bacterial collection was reduced to 43 isolates, based on further selection regarding the genera and the spoilage types previously highlighted. Albeit to different degrees, all these isolates were able to produce proteases. A large part of these isolates also expressed lipolytic and amylolytic activities. This study emphasizes the need to control egg white contamination and especially with Gram-positive heat-resistant Enterococi, in order to guarantee the shelf life of egg-based chilled desserts. PMID:25588552

  8. Measures to reduce ammonia emissions from livestock manures: now, soon and later

    NARCIS (Netherlands)

    Groenestein, C.M.; Smits, M.C.J.; Huijsmans, J.F.M.; Oenema, O.

    2011-01-01

    Various possible options to further decrease ammonia emissions from livestock manure were explored in a desk study. Techniques and their impact on the processes leading to NH3 production and volatilization are described. Research priorities are identified.

  9. Recovery of ammonia and sulfate from waste streams and bioenergy production via bipolar bioelectrodialysis

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2015-01-01

    Ammonia and sulfate, which are prevalent pollutants in agricultural and industrial wastewaters, can cause serious inhibition in several biological treatment processes, such as anaerobic digestion. In this study, a novel bioelectrochemical approach termed bipolar bioelectrodialysis was developed t...

  10. Ammonia inhibition on hydrogen enriched anaerobic digestion of manure under mesophilic and thermophilic conditions

    DEFF Research Database (Denmark)

    Wang, Han; Zhang, Yifeng; Angelidaki, Irini

    2016-01-01

    Capturing of carbon dioxide by hydrogen derived from excess renewable energy (e.g., wind mills) to methane in a microbially catalyzed process offers an attractive technology for biogas production and upgrading. This bioconversion process is catalyzed by hydrogenotrophic methanogens, which are known...... to be sensitive to ammonia. In this study, the tolerance of the biogas process under supply of hydrogen, to ammonia toxicity was studied under mesophilic and thermophilic conditions. When the initial hydrogen partial pressure was 0.5 atm, the methane yield at high ammonia load (7 g NH4+-N L−1) was 41.0% and 22...... methanogens in the hydrogen enriched biogas production and upgrading processes. The highest methane production yield was achieved under 0.5 atm hydrogen partial pressure in batch reactors at all the tested ammonia levels. Furthermore, the thermophilic methanogens at 0.5 atm of hydrogen partial pressure were...

  11. Ammonia emission from crop residues : quantification of ammonia volatilization based on crop residue properties

    NARCIS (Netherlands)

    Ruijter, de F.J.; Huijsmans, J.F.M.

    2012-01-01

    This paper gives an overview of available literature data on ammonia volatilization from crop residues. From these data, a relation is derived for the ammonia emission depending on the N-content of crop residue.

  12. Autotrophic ammonia oxidation by soil thaumarchaea

    OpenAIRE

    Zhang, Li-Mei; Offre, Pierre R.; He, Ji-Zheng; Verhamme, Daniel T.; Nicol, Graeme W.; Prosser, James I.

    2010-01-01

    Nitrification plays a central role in the global nitrogen cycle and is responsible for significant losses of nitrogen fertilizer, atmospheric pollution by the greenhouse gas nitrous oxide, and nitrate pollution of groundwaters. Ammonia oxidation, the first step in nitrification, was thought to be performed by autotrophic bacteria until the recent discovery of archaeal ammonia oxidizers. Autotrophic archaeal ammonia oxidizers have been cultivated from marine and thermal spring environments, bu...

  13. The chilled storage life and retail display performance of vacuum and carbon dioxide packed hot deboned beef striploins.

    Science.gov (United States)

    Bell, R G; Penney, N; Gilbert, K V; Moorhead, S M; Scott, S M

    1996-04-01

    Two cooling regimes that complied with the New Zealand meat hygiene requirement that hot deboned meat be chilled to +7 °C or less within 24 hr of leaving the slaughter floor were evaluated for the production of chilled table meats. Electrically stimulated hot deboned bull beef half striploins were either vacuum or carbon dioxide packed before being cooled in accordance with either Regime 1 (cool at +5 °C for 24 hr, transfer to chiller operating at -1.0 ± 0.5 °C) or Regime 2 (cool at +5 °C for 24 hr, hold at 5 °C for 6 days, transfer to chiller operating at -1.0 ± 0.5 °C). Striploins were removed from -1.0 °C storage 8, 28, 42, 56, 70, 84 and 98 days after slaughter and subjected to microbiological, tenderness, sensory and retail display performance evaluations. Both Regimes 1 and 2 produced meat of acceptable mean tenderness, 8 kgF (MIRINZ Tenderometer) in either vacuum or carbon dioxide packs within 28 and 8 days of slaughter, respectively. However, 70 days after slaughter the first signs of over-ageing became apparent. Steaks from Regimes 1 and 2 maintained acceptable visual appearance during retail display at 5 °C for 48 hr and 24 hr, respectively. After these times, the product was judged by the panel to be unacceptable because of its dull dark lean tissue and grey to green discoloration of the fat. Poor colour stability during retail display was mirrored by deterioration of sensory attributes, particularly aroma which is indicative of incipient spoilage. While carbon dioxide packaging in combination with Regime 1 offered an initial microbiological advantage over vacuum packaging, this advantage was not, however, carried over into retail display. Poor colour and sensory stability during retail display suggest that chilled table cuts derived from hot deboned bull beef are more suited to the Hotel-Restaurant-Institutional (HRI) trade than supermarket retailing. To serve the HRI, vacuum packed hot deboned bull beef primal cuts processed by Regime 1

  14. A multiphysics and multiscale model for low frequency electromagnetic direct-chill casting

    Science.gov (United States)

    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.

  15. Mathematical Modeling of Ammonia Electro-Oxidation on Polycrystalline Pt Deposited Electrodes

    Science.gov (United States)

    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

  16. Tetraammineplatinum(II dichloride ammonia tetrasolvate

    Directory of Open Access Journals (Sweden)

    Tobias Grassl

    2014-07-01

    Full Text Available The title compound, [Pt(NH34]Cl2·4NH3, was crystallized in liquid ammonia from the salt PtCl2. The platinum cation is coordinated by four ammonia molecules, forming a square-planar complex. The chloride anions are surrounded by nine ammonia molecules, either bound within the platinum complex or solvent molecules. The solvent ammonia molecules are packed in such a way that an extended network of N—H...N and N—H...Cl hydrogen bonds is formed. The structure is isotypic with [Pd(NH34]Cl2·4NH3 [Grassl & Korber (2014. Acta Cryst. E70, i32].

  17. Ammonia and urea permeability of mammalian aquaporins

    DEFF Research Database (Denmark)

    Litman, Thomas; Søgaard, Rikke; Zeuthen, Thomas

    2009-01-01

    The human aquaporins,AQP3,AQP7, AQP8,AQP9, and possibly AQP10, are permeable to ammonia, and AQP7, AQP9, and possibly AQP3, are permeable to urea. In humans, these aquaporins supplement the ammonia transport of the Rhesus (Rh) proteins and the urea transporters (UTs). The mechanism by which...... and 9 are found together with Rh proteins in cells exposed to portal blood coming from the intestine. In the kidney, AQP3 might participate in the excretion of NH(4) (+) in the collecting duct. The interplay between the ammonia-permeable aquaporins and the other types of ammonia- and urea...

  18. Avocado by-products as inhibitors of color deterioration and lipid and protein oxidation in raw porcine patties subjected to chilled storage.

    Science.gov (United States)

    Rodríguez-Carpena, J G; Morcuende, D; Estévez, M

    2011-10-01

    Processing of avocados generates an important amount of by-products such as peels and seeds that are rich in bioactive substances with proven radical suppressing activities. The objective of this study was to evaluate the effectiveness of peel and seed extracts from two avocado varieties-'Hass' and 'Fuerte'-as inhibitors of lipid and protein oxidation and color deterioration of raw porcine patties during chilled storage (4 °C/15 days). Avocado extracts significantly (pHass' extracts. Patties treated with avocado extracts had significantly lower amounts of TBA-RS than control ones throughout the storage. 'Hass' avocado extracts significantly inhibited the formation of protein carbonyls in chilled patties at day 15. The present results highlight the potential usage of extracts from avocado by-products as ingredients for the production of muscle foods with enhanced quality traits.

  19. Aesthetic Chills: Knowledge-Acquisition, Meaning-Making, and Aesthetic Emotions.

    Science.gov (United States)

    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

  20. Human response to individually controlled micro environment generated with localized chilled beam

    DEFF Research Database (Denmark)

    Uth, Simon C.; Nygaard, Linette; Bolashikov, Zhecho Dimitrov;

    2014-01-01

    Indoor environment in a single-office room created by a localised chilled beam with individual control of the primary air flow was studied. Response of 24 human subjects when exposed to the environment generated by the chilled beam was collected via questionnaires under a 2-hour exposure including...... different work tasks at three locations in the room. Response of the subjects to the environment generated with a chilled ceiling combined with mixing air distribution was used for comparison. The air temperature in the room was kept at 26 or 28 °C. Results show no significant difference in the overall and...... local thermal sensation reported by the subjects with the two systems. Both systems were equally acceptable. At 26°C the individual control of the localised chilled beam lead to higher acceptability of the work environment. At 28°C the acceptability decreased with the two systems. It was not acceptable...

  1. Two-Pipe Chilled Beam System for Both Cooling and Heating of Office Buildings

    DEFF Research Database (Denmark)

    Afshari, Alireza; Gordnorouzi, Rouzbeh; Hultmark, Göran;

    2013-01-01

    . The building model had a net volume of 3669 m3, (L*B: 25.5m*11.5 m) and net ceiling height of 2.55 m. The building model was assumed to consist of 78 office rooms, 6 meeting rooms and 5 corridors with a 50% occupancy. Simulations were executed using Bsim, an energy simulation program, to calculate the energy...... advantage of renewable energy. The results showed that the energy consumption was 3% less in the 2-pipe chilled beam system in comparison with the conventional 4-pipe system when moving cooled and heated water through the building, transferring the energy to where it is needed. Using free cooling (taking......Simulations were performed to compare a conventional 4-pipe chilled beam system and a 2-pipe chilled beam system. The objective was to establish requirements, possibilities and limitations for a well-functioning 2-pipe chilled beam system for both cooling and heating of office buildings...

  2. Neutrino oscillation provides clues to dark matter and signals from the chilled universe

    CERN Multimedia

    2006-01-01

    The new verification that oscillations exists and neutrinos have mass though not detectible easy provides the first clue to extra dimensions, dark matter, hyperspace and chilled universe acting as a platform below it. (1/2 page)

  3. Aesthetic Chills: Knowledge-Acquisition, Meaning-Making, and Aesthetic Emotions.

    Science.gov (United States)

    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.

  4. Molecular characterization of microbial populations in full-scale biofilters treating iron, manganese and ammonia containing groundwater in Harbin, China.

    Science.gov (United States)

    Li, Xiang-kun; Chu, Zhao-rui; Liu, Ya-jun; Zhu, Meng-ting; Yang, Liu; Zhang, Jie

    2013-11-01

    In iron and manganese-containing groundwater treatment for drinking water production, biological filter is an effective process to remove such pollutants. Until now the exact microbial mechanism of iron and manganese removal, especially coupled with other pollutants, such as ammonia, has not been clearly understood. To assess this issue, the performance of a full-scale biofilter located in Harbin, China was monitored over four months. Microbial populations in the biofilter were investigated using T-RFLP and clone library technique. Results suggested that Gallionella, Leptothrix, Nitrospira, Hyphomicrobium and Pseudomonas are dominant in the biofilter and play major roles in the removal of iron, manganese and ammonia. The spatial distribution of microbial populations along the depth of the biofilter demonstrated the stratification of the removal of iron, manganese and ammonia. Additionally, the absence of ammonia-oxidizing bacteria in the biofilter implicated that ammonia-oxidizing archaea might be responsible for the oxidation of ammonia to nitrite.

  5. Bioaugmentation of an acetate-oxidising anaerobic consortium in up-flow sludge blanket reactor subjected to high ammonia loads

    DEFF Research Database (Denmark)

    Fotidis, Ioannis; Karakashev, Dimitar Borisov; Angelidaki, Irini

    methanogens, in syntrophic association with acetate oxidising bacteria, are more resistant to ammonia toxicity effect. The use of syntrophic acetate oxidising methanogenic consortia could provide a new approach to tackle ammonia toxicity effect in AD. The SAO culture (i.e. Clostridium ultunense spp. nov......Ammonia is the major inhibitor of anaerobic digestion (AD) process leading to suboptimal utilisation of the biogas potential of the feedstocks and causing economical losses to the biogas plants. However, ammonia is mainly inhibiting the aceticlastic methanogens, while the hydrogenotrophic....... in association with Methanoculleus spp. strain MAB1), is an acetate oxidising methanogenic consortium that can produce methane (CH4) at high ammonia levels. In the current study the bioaugmentation of the SAO culture in a mesophilic up-flow anaerobic sludge blanket (UASB) reactor subjected to high ammonia loads...

  6. Ammonia-Free NOx Control System

    Energy Technology Data Exchange (ETDEWEB)

    S. Wu

    2003-12-31

    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 31, 2003 time period.

  7. Ammonia-Free NOx Control System

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Ammonia-Free NOx Control System

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Towards an ammonia-mediated hydrogen economy?

    DEFF Research Database (Denmark)

    Christensen, Claus H.; Johannessen, Tue; Sørensen, Rasmus Zink;

    2006-01-01

    Materialization of a hydrogen economy could provide a solution to significant global challenges, In particular. the possibility of improving the efficiency and simultaneously minimizing the environmental impact of energy conversion processes, together with the opportunity to reduce the dependency...... of fossil fuels, are main drivers for the currently increasing research and development efforts. However. significant technological breakthroughs are necessary for making a hydrogen economy feasible. In particular, it is necessary to develop appropriate hydrogen storage and transportation technologies....... Recently, metal ammine salts were proposed as safe, reversible. high-density and low-cost hydrogen carriers. Here, we discuss how this development could provide a platform for using ammonia as a fuel for the hydrogen economy, We do that by comparing various possible hydrogen carriers with respect to energy...

  10. Effect of heat shock on the chilling sensitivity of trichomes and petioles of African violet (Saintpaulia ionantha).

    Science.gov (United States)

    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

  11. Relationship between N2O production rate and ammonia oxidation rate during nitritation process%短程硝化过程中硝化速率与N2O产生速率的关系

    Institute of Scientific and Technical Information of China (English)

    刘越; 李鹏章; 彭永臻

    2015-01-01

    Nitrous oxide (N2O) is one of the three main greenhouse gases (CO2, CH4, N2O), about 265 times more effective than carbon dioxide (CO2), and it may also destruct the ozone layer. In wastewater biological nitrogen removal process, autotrophic nitrification has been thought to be the major source of N2O production. In this study, by testing the production of N2Ounder different conditions, the relationship between N2Oproduction rate and ammonia oxidation rate during nitritation process was investigated in a laboratory batch-scale system with activated sludge for treating domestic wastewater. The experimental data indicated that the ammonia oxidation rate (AOR) increased with higher DO while N2O production rate (N2OR) increased first then decreased. Besides the AOR and N2OR were by varying the initial ammonium (+4NH-N) concentration in batch experiments. The max N2OR was 1.29 mg N2O·(g MLVSS)−1·h−1 when DO was 0.6 mg·L−1. At low DO level, the increase of AOR would promote the N2OR. On the other hand, higher AOR might not produce more N2O when DO was high. There were different pathways of N2O production under various conditions which led to the change of N2OR. When DO was low, N2O was mainly produced by nitrosyl radical (NOH), while increasing AOR promoted the N2OR formation. However, nitrifier denitrification by AOB was the main way of producing N2O at high DO level. This pathway might be inhibited by high DO, and thus even there was high AOR, the net production of N2O was still less. In addition, the existence of+4NH was very important to N2O production too.%N2O是3种主要的温室气体之一,污水的生物脱氮过程是N2O产生的一个主要人为来源。通过对不同条件下生活污水短程硝化过程中N2O的产生情况进行研究,考察了短程硝化过程中硝化速率(AOR)与N2O产生速率(N2OR)之间的关系。结果表明:随着DO水平的提高,AOR逐渐上升,N2OR则呈现先增加后减少的趋势;最大N2

  12. Reducing ammonia emissions in Europe

    DEFF Research Database (Denmark)

    Jacobsen, Brian H.

    2011-01-01

    The NEC directive has set targets for the 2010 ammonia emissions from a number of European countries. The target will be reached by most EU-countries and the total emission for EU-27 has been reduced by 22% from 1990 to 2007. Denmark is one of the countries with the largest reductions since 1990...... to the high expectations at the outset. Despite this, the paper concludes that Denmark is likely to reduce emission by 50% from 1990 to 2020 and reach the likely 2020 NEC ceiling....

  13. Self-optimizing Control of Cooling Tower for Efficient Operation of Chilled Water Systems

    OpenAIRE

    Li, Xiao; Li, Yaoyu; Seem, John E.; Li, Pengfei

    2012-01-01

    The chilled-water systems, mainly consisting of electric chillers and cooling towers, are crucial for the ventilating and air conditioning systems in commercial buildings. Energy efficient operation of such systems is thus important for the energy saving of commercial buildings. This paper presents an extremum seeking control (ESC) scheme for energy efficient operation of the chilled-water system, and presents a Modelica based dynamic simulation model for demonstrating the effectiveness of th...

  14. The effect of lethal doses of X-rays on chilled and thyroidectomized animals

    Energy Technology Data Exchange (ETDEWEB)

    Hempelmann, L.H.; Trujillo, T.T.; Knowlton, N.P. Jr.

    1949-04-19

    The chilling of animals has been shown to offer some protection from the lethal effects of radiation. An effort has been made to extend the study of the effects of chilling on the lethal effects of x radiation and to determine whether or not the lowering of the basal metabolic rate by thyroidectomy will give similar protection. Five experiments were carried out using mice and rats as the experimental animals.

  15. Effect of LaCI3 on the chilling tolerance of rice seedlings

    Institute of Scientific and Technical Information of China (English)

    LIMeiru; LIUHongxian; WANGYirou

    1997-01-01

    The rice variety Tesanai 2 is susceptible to chilling. Exposure of the seedlings grown at 28±1℃ and under a photo flux density(PFD) of 30 μmol/m2s to 1℃ and under a PFD of 150μmol/m2s for 2 d caused a physiological disorder called chilling injury which reduced the survival rate to 50%.

  16. Exploring Aesthetic Chill Parameters and their Associations with Demographic, Lifestyle and Personality Variables

    OpenAIRE

    Hobbel, Sabine Hobbel

    2010-01-01

    This dissertation reviews the literature on individual differences associated with the experience of Aesthetic Chills, and reports a large questionnaire study, completed by 46 international students. Ordinal logistic regressions confirmed previously reported significant and positive relations between Openness and the frequency of Aesthetic Chills in poetry and music (McCrae 2007; Kunkel, Pramstaller, Grant, & von Georgi, 2008). Prior reported correlations between the frequency of Aesthetic Ch...

  17. Preparation and characterization of microparticles of piroxicam by spray drying and spray chilling methods

    OpenAIRE

    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 ...

  18. Conventional food preparation, cook and chill and sous-vide as optional methods for institutional kitchens. Perinteinen ruoanvalmistus, cook and chill ja sous-vide toimintavaihtoehdot suurkeittioessae

    Energy Technology Data Exchange (ETDEWEB)

    Paeivaerinta, T., Reisbacka, A., Salminen, M.

    1993-01-01

    The purpose of the study was to clarify the situation concerning the energy consumption, economics and the appropriateness of the three options when applied in institutional households. The options included in the study were conventional (preparation-cooking-serving), cook and chill and sous-vide (vacuum cooking-chilling). A further aim was to compare industrially produced products to self-made products. Each option was studied in connection with several devices embodying latest technology. The overall price for a portion was found to be cheapest when using the conventional preparation method. The cook and chill method was only slightly more expensive. The result of this study also support the understanding that when appropriately planned, cook and chill and sous-vide food preparation options make possible the rationalisation of kitchen work. The appropriateness of different food preparation methods depends on the versatility of the functions and programmes built into cooking devices. A combination oven is appropriate and conserves energy when cooking or heating up large quantities. Significant waste of water (126-146 1/h) is possible because of the structural solutions and modes of use of such an oven. A microwave oven saves energy when used to heat up ready-made portions. The amount of energy consumed by an air-cooled chilling cabinet in the cooling of food makes it more economical to use than a water-cooled model. The amount of electricity consumed by a refrigerator or an equivalent cold storage is 5-14 times less than that consumed by chilling devices

  19. Studies on Ammonia Spectral Signatures Relevant to Jupiter's Clouds

    Science.gov (United States)

    Oza, A. U.; Marschall, J.; Wong, M. H.; Kalogerakis, K. S.

    2006-12-01

    Observational evidence and thermochemical models indicate an abundance of ammonia ice clouds in Jupiter's atmosphere. However, spectrally identifiable ammonia ice clouds are found covering less than 1% of Jupiter's atmosphere, notably in turbulent areas [1,2]. Current literature suggests two possible explanations: coating by a hydrocarbon haze and/or photochemical processing ("tanning")[2,3]. We are pursuing a research program investigating the above hypotheses. In the experiments, thin films of ammonia ices are deposited in a cryogenic apparatus, coated with hydrocarbons, and characterized by infrared spectroscopy. The ice films can be irradiated by ultraviolet light to study their photochemistry. The spectroscopic measurements aim to identify the processes that control the optical properties of the ice mixtures and quantify their dependence on the identity of the coating, the temperature, and the ice composition. We have observed a consistent suppression of the ammonia absorption feature at 3 μm with coverage by thin layers of hydrocarbons. Modeling calculations of the multi-layer thin films assist in the interpretation of the experimental results and reveal the role of optical interference in masking the aforementioned ammonia spectral feature. The implications of these results for Jupiter's atmosphere will be discussed. Funding from the NSF Planetary Astronomy Program under grant AST-0206270 and from the NASA Outer Planets Research Program under grant NNG06GF37G is gratefully acknowledged. The participation of Anand Oza (Princeton University) was made possible by the NSF Research Experiences for Undergraduates Program under grant PHY-0353745. 1. S. K. Atreya, A.-S. Wong, K. H. Baines, M. H. Wong, T. C. Owen, Planet. Space Science 53, 498 (2005). 2. K. H. Baines, R. W. Carlson, and L. W. Kamp, Icarus 159, 74 (2002). 3. A.-S. Wong, Y. L. Yung, and A. J. Friedson, Geophys. Res. Lett. 30, 1447 (2003).

  20. Study on adsorption and desorption of ammonia on graphene.

    Science.gov (United States)

    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.

  1. Fabrication of a photocurable highly sensitive optical ammonia sensor for aquaculture application

    Science.gov (United States)

    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.

  2. REGENERATION OF AMMONIA SOLUTION FOR CO2 CAPTURE IN POSTCOMBUSTION

    Directory of Open Access Journals (Sweden)

    CAROL TORO

    2014-01-01

    Full Text Available This study investigated enthalpy of solutions and solubility for a NH3/CO2 system. Measurements were performed in a thermoregulated Lewis-type cell reactor, temperatures ranging from 278 to 303 K and mass concentrations from 2 wt% to 5 wt%. Enthalpies of solution of CO2 and solubility have been obtained as function of loading, α (moles CO2/mol NH3. Results show that ammonia solutions concentrations of 3 and 5 wt% promote the formation of ammonium bicarbonate. Beside, ammonia concentration of 2 wt% promotes the formation of ammonium carbonate. Therefore, to use ammonia concentrations of 3 and 5 wt% need less energy that a concentration of 2 wt% to reverse the reaction. Regeneration system was simulated using Aspen plus™ software for a pulverised coal fired power plant (CF in a post-combustion process. Model analysis established that NH3 heat duty is lower than MEA and MDEA ones. The energy consumption reaches 2.83 GJ•t-1 CO2. Regarding heat duty and ammonia losses, 3 wt% NH3 is the suitable concentration to capture CO2.

  3. System Modeling for Ammonia Synthesis Energy Recovery System

    Science.gov (United States)

    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.

  4. Improving chill control in iron powder treated slightly hypereutectic grey cast irons

    Directory of Open Access Journals (Sweden)

    Iulian Riposan

    2011-05-01

    Full Text Available Recent studies revealed that in eutectic to slightly hypereutectic grey irons (CE = 4.3%-4.5% the presence of austenite dendrites provides an opportunity to improve the cast iron properties, as a high number of eutectic cells are “reinforced” by austenite dendrites. An iron powder addition proved to be important by promoting dendritic austenite in hypereutectic irons, but was accompanied by adverse effect on the characteristics of potential nuclei for graphite. The purpose of the present paper is to investigate the solidification pattern of these irons. Chill wedges with different cooling moduli (CM = 0.11 – 0.43 cm were poured in resin bonded sand and metal moulds. Relative clear / mottled / total chill measurement criteria were applied. Iron powder additions led to a higher chill tendency, while single inoculation showed the strongest graphitizing effect. The various double treatments show an intermediate position, but the inoculant added after iron powder appears to be the most effective in reducing base iron chill tendency, for all cooling moduli and chill evaluation parameters. This performance reflects the improved properties of (Mn,XS polygonal compounds as nucleation sites for graphite, especially in resin bonded sand mould castings. Both austenite and graphite nucleation benefit from a double addition of iron powder + inoculant, with positive effect on the final structure and chill tendency.

  5. A missense mutation in CHS1, a TIR-NB protein, induces chilling sensitivity in Arabidopsis.

    Science.gov (United States)

    Wang, Yuancong; Zhang, Yao; Wang, Zheng; Zhang, Xiaoyan; Yang, Shuhua

    2013-08-01

    Low temperature is an environmental factor that affects plant growth and development and plant-pathogen interactions. How temperature regulates plant defense responses is not well understood. In this study, we characterized chilling-sensitive mutant 1 (chs1), and functionally analyzed the role of the CHS1 gene in plant responses to chilling stress. The chs1 mutant displayed a chilling-sensitive phenotype, and also displayed defense-associated phenotypes, including extensive cell death, the accumulation of hydrogen peroxide and salicylic acid, and an increased expression of PR genes: these phenotypes indicated that the mutation in chs1 activates the defense responses under chilling stress. A map-based cloning analysis revealed that CHS1 encodes a TIR-NB-type protein. The chilling sensitivity of chs1 was fully rescued by pad4 and eds1, but not by ndr1. The overexpression of the TIR and NB domains can suppress the chs1-conferred phenotypes. Interestingly, the stability of the CHS1 protein was positively regulated by low temperatures independently of the 26S proteasome pathway. This study revealed the role of a TIR-NB-type gene in plant growth and cell death under chilling stress, and suggests that temperature modulates the stability of the TIR-NB protein in Arabidopsis.

  6. Use of the spray chilling method to deliver hydrophobic components: physical characterization of microparticles

    Directory of Open Access Journals (Sweden)

    Izabela Dutra Alvim

    2013-02-01

    Full Text Available Food industry has been developing products to meet the demands of increasing number of consumers who are concerned with their health and who seek food products that satisfy their needs. Therefore, the development of processed foods that contain functional components has become important for this industry. Microencapsulation can be used to reduce the effects of processing on functional components and preserve their bioactivity. The present study investigated the production of lipid microparticles containing phytosterols by spray chilling. The matrices comprised mixtures of stearic acid and hydrogenated vegetable fat, and the ratio of the matrix components to phytosterols was defined by an experimental design using the mean diameters of the microparticles as the response variable. The melting point of the matrices ranged from 44.5 and 53.4 ºC. The process yield was melting point dependent; the particles that exhibited lower melting point had greater losses than those with higher melting point. The microparticles' mean diameters ranged from 13.8 and 32.2 µm and were influenced by the amount of phytosterols and stearic acid. The microparticles exhibited spherical shape and typical polydispersity of atomized products. From a technological and practical (handling, yield, and agglomeration points of view, lipid microparticles with higher melting point proved promising as phytosterol carriers.

  7. Ammonia Sensing Behaviors of TiO2-PANI/PA6 Composite Nanofibers

    OpenAIRE

    Fenglin Huang; Qufu Wei; Xin Xia; Zengyuan Pang; Yuanzhi Du; Xianjun Dong; Qingqing Wang

    2012-01-01

    Titanium dioxide-polyaniline/polyamide 6 (TiO2-PANI/PA6) composite nanofibers were prepared by in situ polymerization of aniline in the presence of PA6 nanofibers and a sputtering-deposition process with a high purity titanium sputtering target. TiO2-PANI/PA6 composite nanofibers and PANI/PA6 composite nanofibers were fabricated for ammonia gas sensing. The ammonia sensing behaviors of the sensors were examined at room temperature. All the results indicated that the ammonia sensing property o...

  8. Mediterranean Berries as Inhibitors of Lipid Oxidation in Porcine Burger Patties Subjected to Cooking and Chilled Storage

    Institute of Scientific and Technical Information of China (English)

    Rui Ganho; Mario Estvez; Mnica Armenteros; David Morcuende

    2013-01-01

    The efifciency of extracts from Arbutus unedo L. (AU), Crataegus monogyna L. (CM), Rosa canina L. (RC), and Rubus ulmifolius Schott. (RU) to inhibit lipid oxidation in raw, cooked and cooked and chilled (2°C/12 d) porcine burger patties, was investigated. The modiifcation of the fatty acid proifle during processing treatments (cooking and chilling), the quantitative measurements of thiobarbituric acid reactive substances (TBA-RS), and lipid-derived volatiles, were used as indicators of lipid oxidation. Polyunsaturated fatty acids (PUFA) gradually decreased during cooking and the subsequent storage of cooked burger patties with this decrease being signiifcantly greater (P<0.05) in control patties than in those with added berry extracts. In accordance, the control patties showed signiifcantly higher TBA-RS numbers and counts of lipid-derived volatiles in all treatments when compared to the berry-added counterparts (P<0.05). Results from the present work show, for the ifrst time, that extracts from A. unedo, C. monogyna, R. canina, and R. ulmifolius are promising antioxidants which could enhance the nutritional, safety and sensory properties of porcine burger patties.

  9. Atmospheric behaviour of ammonia and ammonium.

    NARCIS (Netherlands)

    Asman, W.A.J.

    1987-01-01

    1.4.1 Scope of this thesisA few models for ammonia and ammonium exist. Russell et al. (1983) made a multi-layer Lagrangian transport model describing the transport and formation of ammonium nitrate aerosol for California. They did not take reactions of ammonia and sulphuric acid into account, nor we

  10. Nitrocarburizing in ammonia-hydrocarbon gas mixtures

    DEFF Research Database (Denmark)

    Pedersen, Hanne; Christiansen, Thomas; Somers, Marcel A. J.

    2011-01-01

    The present work investigates the possibility of nitrocarburising in ammonia-acetylene-hydrogen and ammonia-propene-hydrogen gas mixtures, where unsaturated hydrocarbon gas is the carbon source during nitrocarburising. Consequently, nitrocarburising is carried out in a reducing atmosphere and str...

  11. Regeneration of ammonia borane from polyborazylene

    Science.gov (United States)

    Sutton, Andrew; Gordon, John C; Ott, Kevin C; Burrell, Anthony K

    2013-02-05

    Method of producing ammonia borane, comprising providing a reagent comprising a dehydrogenated material in a suitable solvent; and combining the reagent with a reducing agent comprising hydrazine, a hydrazine derivative, or combinations thereof, in a reaction which produces a mixture comprising ammonia borane.

  12. Method for releasing hydrogen from ammonia borane

    Science.gov (United States)

    Varma, Arvind; Diwan, Moiz; Shafirovich, Evgeny; Hwang, Hyun-Tae; Al-Kukhun, Ahmad

    2013-02-19

    A method of releasing hydrogen from ammonia borane is disclosed. The method comprises heating an aqueous ammonia borane solution to between about 80-135.degree. C. at between about 14.7 and 200 pounds per square inch absolute (psia) to release hydrogen by hydrothermolysis.

  13. Ammonia and hydrogen sulfide removal using biochar

    Science.gov (United States)

    Reducing ammonia and hydrogen sulfide emissions from livestock facilities is an important issue for many communities and livestock producers. Ammonia has been regarded as odorous, precursor for particulate matter (PM), and contributed to livestock mortality. Hydrogen sulfide is highly toxic at elev...

  14. Ammonia Solubility in High Concentration Salt Solutions

    International Nuclear Information System (INIS)

    Solubility data for ammonia in water and various dilute solutions are abundant in the literature. However, there is a noticeable lack of ammonia solubility data for high salt, basic solutions of various mixtures of salts including those found in many of the Hanford Washington underground waste tanks. As a result, models based on solubility data for dilute salt solutions have been used to extrapolate to high salt solutions. These significant extrapolations need to be checked against actual laboratory data. Some indirect vapor measurements have been made. A more direct approach is to determine the ratio of solubility of ammonia in water to its solubility in high salt solutions. In various experiments, pairs of solutions, one of which is water and the other a high salt solution, are allowed to come to equilibrium with a common ammonia vapor pressure. The ratio of concentrations of ammonia in the two solutions is equal to the ratio of the respective ammonia solubilities (Henry's Law constants) at a given temperature. This information can then be used to refine the models that predict vapor space compositions of ammonia. Ammonia at Hanford is of concern because of its toxicity in the environment and its contribution to the flammability of vapor space gas mixtures in waste tanks

  15. Effects of carbon dioxide emission, kinetically-limited reactions, and diffusive transport on ammonia emission from manure

    Science.gov (United States)

    Volatilization of ammonia (NH3) from animal manure causes significant loss of fixed N from livestock operations. Ammonia emission from manure is the culmination of biological, chemical, and physical processes, all of which are well-understood. In this work, we present a speciation and transport mode...

  16. Monnte Carlo Simulation of Kinetics of Ammonia Oxidative Decomposition over the Commercial Propylene Ammoxidation Catalyst(Mo-Bi)

    Institute of Scientific and Technical Information of China (English)

    罗正鸿; 詹晓力; 等

    2003-01-01

    Monte Carlo method is applied to investigate the kinetics of ammonia oxidative decomposition over the commercial propylene ammoxidation catalyst(Mo-Bi).The simulation is quite in agreement with experimetal results.Monte Carlo simulation proves that the process of ammonia oxidation decomposition is a two-step reaction.

  17. Salmonella and Campylobacter reduction and quality characteristics of poultry carcasses treated with various antimicrobials in a post-chill immersion tank.

    Science.gov (United States)

    Nagel, G M; Bauermeister, L J; Bratcher, C L; Singh, M; McKee, S R

    2013-08-01

    Innovations in poultry processing include implementation of antimicrobials in post-chill decontamination tanks. In this study, a total of 160 broiler carcasses were analyzed to evaluate the efficacy of five post-chill water treatments consisting of 0.004% (40ppm) total chlorine, 0.04% (400ppm) or 0.1% (1000ppm) peracetic acid (PAA), and 0.1% (1000ppm) or 0.5% (5000ppm) lysozyme against Salmonella and Campylobacter spp. In addition, sensory analysis was performed to evaluate any associated effects of the antimicrobials on quality attributes of chicken breast meat. Treatment with 0.04% and 0.1% PAA was most effective (P≤0.05) in reducing populations of Salmonella and Campylobacter as compared to the chlorine treatment at 0.004% and lysozyme treatments at 0.1% and 0.5%, as well as the water treatment and the positive control. Treatment with the various antimicrobials was not found to have negative (P≤0.05) impacts on sensory attributes. Results from this study suggest that utilizing PAA as an antimicrobial in a post-chill immersion tank is an effective application for reducing Salmonella and Campylobacter on carcasses while maintaining product quality.

  18. On-board hydrogen storage and production: An application of ammonia electrolysis

    Science.gov (United States)

    Boggs, Bryan K.; Botte, Gerardine G.

    On-board hydrogen storage and production via ammonia electrolysis was evaluated to determine whether the process was feasible using galvanostatic studies between an ammonia electrolytic cell (AEC) and a breathable proton exchange membrane fuel cell (PEMFC). Hydrogen-dense liquid ammonia stored at ambient temperature and pressure is an excellent source for hydrogen storage. This hydrogen is released from ammonia through electrolysis, which theoretically consumes 95% less energy than water electrolysis; 1.55 Wh g -1 H 2 is required for ammonia electrolysis and 33 Wh g -1 H 2 for water electrolysis. An ammonia electrolytic cell (AEC), comprised of carbon fiber paper (CFP) electrodes supported by Ti foil and deposited with Pt-Ir, was designed and constructed for electrolyzing an alkaline ammonia solution. Hydrogen from the cathode compartment of the AEC was fed to a polymer exchange membrane fuel cell (PEMFC). In terms of electric energy, input to the AEC was less than the output from the PEMFC yielding net electrical energies as high as 9.7 ± 1.1 Wh g -1 H 2 while maintaining H 2 production equivalent to consumption.

  19. Pretreatment of anaerobic digestion effluent with ammonia stripping and biogas purification.

    Science.gov (United States)

    Lei, Xiaohui; Sugiura, Norio; Feng, Chuanping; Maekawa, Takaaki

    2007-07-16

    In this study, ammonia stripping was optimized for pretreating anaerobic digestion effluent from an anaerobic digestion plant, and the possibility of using CO(2) stripping and biogas injection for adjusting the pH of the effluent before and after the ammonia stripping process was also investigated. For ammonia stripping, the results showed that an overdose of calcium hydroxide, i.e., 27.5g/L wastewater, achieved higher ammonia, phosphorus, chemical oxygen demand, suspended solids, and turbidity removal efficiency. An air flow rate of 5L/min for 1L of wastewater was thought as suitable for engineering application. The pH of the anaerobic digestion effluent can be increased from about 7 to about 9 by CO(2) stripping, however which is insufficient for ammonia stripping. For 1L of wastewater treated after ammonia stripping, the pH can be neutralized to about 7 from greater than 11 through biogas injection at 1L/min for less than 30min, and continuous injection does not decrease the pH. It was roughly estimated that 43m(3) of biogas (CH(4):CO(2) approximately 60%:40%) produced daily could be purified to CH(4):CO(2) approximately 74%:26% by neutralizing the pH of the 5m(3) anaerobic digestion effluent pretreated by ammonia stripping. PMID:17178436

  20. Clinical utility of breath ammonia for evaluation of ammonia physiology in healthy and cirrhotic adults.

    Science.gov (United States)

    Spacek, Lisa A; Mudalel, Matthew; Tittel, Frank; Risby, Terence H; Solga, Steven F

    2015-12-01

    Blood ammonia is routinely used in clinical settings to assess systemic ammonia in hepatic encephalopathy and urea cycle disorders. Despite its drawbacks, blood measurement is often used as a comparator in breath studies because it is a standard clinical test. We sought to evaluate sources of measurement error and potential clinical utility of breath ammonia compared to blood ammonia. We measured breath ammonia in real time by quartz enhanced photoacoustic spectrometry and blood ammonia in 10 healthy and 10 cirrhotic participants. Each participant contributed 5 breath samples and blood for ammonia measurement within 1 h. We calculated the coefficient of variation (CV) for 5 breath ammonia values, reported medians of healthy and cirrhotic participants, and used scatterplots to display breath and blood ammonia. For healthy participants, mean age was 22 years (±4), 70% were men, and body mass index (BMI) was 27 (±5). For cirrhotic participants, mean age was 61 years (±8), 60% were men, and BMI was 31 (±7). Median blood ammonia for healthy participants was within normal range, 10 μmol L(-1) (interquartile range (IQR), 3-18) versus 46 μmol L(-1) (IQR, 23-66) for cirrhotic participants. Median breath ammonia was 379 pmol mL(-1) CO2 (IQR, 265-765) for healthy versus 350 pmol mL(-1) CO2 (IQR, 180-1013) for cirrhotic participants. CV was 17  ±  6%. There remains an important unmet need in the evaluation of systemic ammonia, and breath measurement continues to demonstrate promise to fulfill this need. Given the many differences between breath and blood ammonia measurement, we examined biological explanations for our findings in healthy and cirrhotic participants. We conclude that based upon these preliminary data breath may offer clinically important information this is not provided by blood ammonia.

  1. Processing Experiments and Engineering on High Concentrated Ammonia and Heavy Metals Composite Wastewater%高浓度氨氮-重金属复合废水资源化处理试验及工程研究

    Institute of Scientific and Technical Information of China (English)

    蒋晓云

    2014-01-01

    针对高浓度氨氮-重金属复合废水,采用HSJ脱氨-资源化回收技术-电化学组合工艺,研究分析了废水pH、进料流量、进塔温度对脱氨-资源化回收系统脱除氨氮的影响、废水pH、电流密度、电解时间对电化学去除重金属的影响及整套系统运行稳定性。结果表明:当pH=12,进塔温度=95℃、进料流量=8 m3/h、蒸汽流量=1.2 m3/h时, HSJ脱氨-资源化回收技术氨氮去除率>99%,出水氨氮稳定低于15 mg/L。当pH=9、电流密度=40 A/m2、电解时间=40 min时,电化学系统出水中铅、锑去除率>99%,出水中铅、锑稳定小于0.5 mg/L。HSJ脱氨-资源化回收技术-电化学组合工艺处理高浓度氨氮-重金属复合废水具有良好的运行稳定性。%The com bined processofH SJam m onia rem ovaland recycling with electrocoagulation wasapplied to treat high concentration ofammonia and heavy metalcombined polluted waste water. The impactofpH,influentvelocity and towerinlettemperature on ammonia removalefficiency forthe whole system and impactofpH,currentdensity and electrolysistime on the heavy metalremovalefficiency and the steadinessofthe whole system were researched. Itwasshown thatwhen pH is12,towerinlettem perature is95 Celsiusdegrees,influentvelocity is8 m 3/h and steam velocity is1.2 m 3/h,the am m onia rem ovalefficiency ishigh than 99 % and effluentconcentration islow erthan 15 m g/L. When pH is9,currentdensity is40 A/m2,electrolysistime is40 minutes,the Pb and Sb'sremovalefficiency ishigh than 99 % and effluent concentration of Pb and Sb is both lower than 0.5 m g/L.The com bined process of H SJ am m onia rem oval and recycling w ith electrocoagulation is feasible and suitable for treating high concentration of am m onia and heavy m etalwastewaterand the system isof high steadiness.

  2. Film with anthocyanins as an indicator of chilled pork deterioration

    Directory of Open Access Journals (Sweden)

    Luana Baptista Golasz

    2013-02-01

    Full Text Available An indicator can be defined as a substance which indicates the presence or absence of another substance or the degree of a certain reaction through characteristic changes, especially color. Therefore, the aim of this work is to evaluate the performance of a bio-based film with anthocyanin as an indicator of chilled pork deterioration. A film made of cassava starch, glycerol, and grape anthocyanins was prepared using the casting technique. Pork loin samples were put in Petri dishes containing an anthocyanin film on the bottom and stored at 4 ºC. Psychrotrophic microorganism count and the pH of the pork loin samples were analyzed for a 14 day- period. At the same time, the films were subjected to colorimetric analysis using D65 illuminant and the CIELAB system. Chroma and hue angle data for these films were evaluated by Anova and Dunnett's test. An increase in the microbial population and in the pH was observed over the storage period as result of pork deterioration. Color changes were also identified in the film. However, only at the beginning of the storage period was it possible to establish a correlation between film color and pork deterioration. The shelf life end-point could not be clearly detected by the film.

  3. Running Club Warm Up Staves Off Winter's Chill

    CERN Multimedia

    2001-01-01

    Not deterred by winter's chill, over 900 runners met at the CERN Prévesin site for Escalade training. Think the sudden cold snap is a reason to stay indoors? Think again! The CERN running club has just recently had the honour of holding the November 11th Escalade training session, and with over 900 runners present at the Prévessin site it was clear that the chilly temperatures were no barrier whatsoever. The story behind Escalade training starts back in 1977 when a group of running enthusiasts from the Stade Genève club decided to organize a running race in the Old Town in conjunction with the Escalade festivities. They were told that no normal people would think of organizing a running race in the month of December, but fortunately they ignored the advice! From the initial 50 or so runners, these Escalade races have grown into an institution and now attract upwards of 15,000 people of all ages from 5 to over 80 each year. And with over 30% of each year's runners participat...

  4. Soft Sensor for Ammonia Concentration at the Ammonia Converter Outlet Based on an Improved Group Search Optimization and BP Neural Network

    Institute of Scientific and Technical Information of China (English)

    阎兴頔; 杨文; 马贺贺; 侍洪波

    2012-01-01

    The ammonia synthesis reactor is the core unit in the whole ammonia synthesis production. The ammo- nia concentration at the ammonia converter outlet is a significant process variable, which reflects directly the pro- duction efficiency. However, it is hard to be measured reliably online in real applications. In this paper, a soft sensor based on BP neural network (BPNN) is applied to estimate the ammonia concentration. A modified group search optimization with nearest neighborhood (GSO-NH) is proposed to optimize the weights and thresholds of BPNN. GSO-NH is integrated with BPNN to build a soft sensor model. Finally, the soft sensor model based on BPNN and GSO-NH (GSO-NH-NN) is used to infer the outlet ammonia concentration in a real-world application. Three other modeling methods are applied for comparison with GSO-NH-NN. The results show that the soft sensor based on GSO-NH-NN has a good prediction performance with high accuracy. Moreover, the GSO-NH-NN also provides good generalization ability to other modeling problems in ammonia synthesis production.

  5. Genome wide identification of chilling responsive microRNAs in Prunus persica

    Directory of Open Access Journals (Sweden)

    Barakat Abdelali

    2012-09-01

    species. Several conserved and non-conserved miRNAs and miRNA-regulated genes co-localize with Quantitative Trait Loci (QTLs for chilling requirement (CR-QTL and bloom date (BD-QTL. Conclusions In this work, we identified a large set of conserved and non-conserved miRNAs and describe their evolutionary footprint in angiosperm lineages. Several of these miRNAs were induced in winter buds and co-localized with QTLs for chilling requirement and bloom date thus making their gene targets potential candidates for mediating plant responses to cold stress. Several peach homologs of genes participating in the regulation of vernalization in Arabidopsis were identified as differentially expressed miRNAs targets, potentially linking these gene activities to cold responses in peach dormant buds. The non-conserved miRNAs may regulate cellular, physiological or developmental processes specific to peach and/or other tree species.

  6. Genome-wide Association Analysis of Ten Chilling Tolerance Indices at the Germination and Seedling Stages in Maize

    Institute of Scientific and Technical Information of China (English)

    Juan Huang; Jianhua Zhang; Wenzhen Li; Wei Hu; Lichao Duan; Yang Feng; Fazhan Qiu

    2013-01-01

    Maize seedlings are very sensitive to chilling,especially during the transition phase from heterotrophic to autotrophic growth.Genetic dissection of the genetic basis of chilling tolerance would provide useful information for genetic improvement of maize inbreds.In this study,genome-wide association analysis was conducted to explore the genetic architecture of maize chilling tolerance at the seed germination and seedling stages with an association panel of 125 inbreds.Ten tolerance indices (ratios of the performance of 10 germination rates and seedling growth-related traits under chilling stress and control conditions)were investigated to assess the ability of chilling tolerance of the inbreds,and a total of 43 single nucleotide polymorphisms associated with chilling tolerance were detected,with none of them being related to chilling tolerance at both the germination and seedling stages simultaneously.Correlation analysis also revealed that the genetic basis of chilling tolerance at the seed germination stage is generally different from that at the seedling stage.In addition,a total of 40 candidate genes involving 31 of the 43 single nucleotide polymorphisms were predicted,and were grouped into five categories according to their functions.The possible roles of these candidate genes in chilling tolerance were also discussed.

  7. Genome-wide association analysis of ten chilling tolerance indices at the germination and seedling stages in maize.

    Science.gov (United States)

    Huang, Juan; Zhang, Jianhua; Li, Wenzhen; Hu, Wei; Duan, Lichao; Feng, Yang; Qiu, Fazhan; Yue, Bing

    2013-08-01

    Maize seedlings are very sensitive to chilling, especially during the transition phase from heterotrophic to autotrophic growth. Genetic dissection of the genetic basis of chilling tolerance would provide useful information for genetic improvement of maize inbreds. In this study, genome-wide association analysis was conducted to explore the genetic architecture of maize chilling tolerance at the seed germination and seedling stages with an association panel of 125 inbreds. Ten tolerance indices (ratios of the performance of 10 germination rates and seedling growth-related traits under chilling stress and control conditions) were investigated to assess the ability of chilling tolerance of the inbreds, and a total of 43 single nucleotide polymorphisms associated with chilling tolerance were detected, with none of them being related to chilling tolerance at both the germination and seedling stages simultaneously. Correlation analysis also revealed that the genetic basis of chilling tolerance at the seed germination stage is generally different from that at the seedling stage. In addition, a total of 40 candidate genes involving 31 of the 43 single nucleotide polymorphisms were predicted, and were grouped into five categories according to their functions. The possible roles of these candidate genes in chilling tolerance were also discussed. PMID:23551400

  8. Thermal desorption of ammonia from crystalline forsterite surfaces

    OpenAIRE

    Suhasaria, T.; Thrower, J. D.; Zacharias, H.

    2015-01-01

    The thermal desorption of ammonia (NH$_3$) from single crystal forsterite (010) has been investigated using temperature-programmed desorption. The effect of defects on the desorption process has been probed by the use of a rough cut forsterite surface prepared from the cleaved forsterite sample. Several approaches have been used to extract the desorption energy and pre-exponential factor describing the desorption kinetics. In the sub-monolayer coverage regime, the NH$_3$ desorption shows a br...

  9. Diversity of Ammonia Oxidizing Archaea in Tropical Compost Systems

    OpenAIRE

    Vidya eDe Gannes; Gaius eEudoxie; Dyer, David H.; William James Hickey

    2012-01-01

    Composting is widely used to transform waste materials into valuable agricultural products. In the tropics, large quantities of agricultural wastes could be potentially useful in agriculture after composting. However, while microbiological processes of composts in general are well established, relatively little is known about microbial communities that may be unique to these in tropical systems, particularly nitrifiers. The recent discovery of ammonia oxidizing archaea (AOA) has changed the p...

  10. Porous Materials for Hydrolytic Dehydrogenation of Ammonia Borane

    OpenAIRE

    Tetsuo Umegaki; Qiang Xu; Yoshiyuki Kojima

    2015-01-01

    Hydrogen storage is still one of the most significant issues hindering the development of a “hydrogen energy economy”. Ammonia borane is notable for its high hydrogen densities. For the material, one of the main challenges is to release efficiently the maximum amount of the stored hydrogen. Hydrolysis reaction is a promising process by which hydrogen can be easily generated from this compound. High purity hydrogen from this compound can be evolved in the presence of solid acid or metal based ...

  11. A novel way to synthesize Pb nanotapes in liquid ammonia

    Institute of Scientific and Technical Information of China (English)

    Lei Sun; Meng Lei Zhang; Xiao Jun Tao; Yan Bao Zhao

    2011-01-01

    Lead nanotapes were synthesized in liquid ammonia solvent in the presence of sodium metal at low temperature. The process was template free. Transmission electron microscopy (TEM) observations and X-ray diffraction (XRD) characterizations revealed that the as-prepared Pb nanotapes have average diameters in the range of 40-50 nm, and lengths up to several hundred nanometers, and exhibit cubic crystal structures.

  12. Analysis of Cryogenic Ammonia System for Energy Conservation

    OpenAIRE

    B. Raei; F. Shahraki; Khorrami, M.; A. Ghadi

    2010-01-01

    There are several alternatives to enhance the efficiency of energy usage and to decrease energy losses. Pinch technology is the best method of approach to enhance energy efficiency. Heat exchangers network (HEN) of refrigeration unit of ammonia production process was analyzed to use pinch technology to decrease energy usage. The obtained results showed that pinch technology was unsuccessful for the shaft work targeting capabilities. In contrast, it is posed that for optimization of such syste...

  13. Chilling requirements for hatching of a New Zealand isolate of Nematodirus filicollis.

    Science.gov (United States)

    Oliver, A-M B; Pomroy, W E; Ganesh, S; Leathwick, D M

    2016-08-15

    The eggs of some species of the parasitic nematode Nematodirus require a period of chilling before they can hatch; N. filicollis is one such species. This study investigated this requirement for chilling in a New Zealand strain of this species. Eggs of N. filicollis were extracted from lamb's faeces and incubated at 20°C to allow development to the third stage larvae within the egg. These eggs were then placed into tissue culture plates and incubated at: 2.7°C (±0.99), 3.6°C (±0.90), 4.7°C (±0.35), 6.4°C (±0.37), 8.0°C (±1.54) or 9.9°C (±0.14) for up to 224 days. At 14day intervals until day 84, then every 28 days, one plate was removed from each temperature and placed at 13.1°C (±0.44) for 14 days. Eggs were then assessed for hatching. From this data, chill units were calculated by subtracting the culture temperature from a constant threshold of 11°C and multiplying by the number of days for which the sample was cultured; then the Gompertz model fitted. Even though hatching overall was low, a greater proportion of eggs hatched with chill accumulation. Maximum hatching of eggs required 800-1000 chill units. Consequently in the field, more than one season of chilling would be required before hatching. As such a generation time could take more than one year to complete. This is different to the hatching dynamics of N. spathiger, the other main species found in New Zealand sheep, which does not display this requirement for chilling and hatches immediately once the third stage larvae are developed.

  14. Experimental research on removing cyanide and ammonia nitrogen from industrial waste water produced by gold smelting with electro-catalytic oxidation process%电催化氧化法去除黄金冶炼废水中氰化物和氨氮试验研究

    Institute of Scientific and Technical Information of China (English)

    方荣茂; 廖小山; 廖斌; 林烽先; 刘亚建

    2013-01-01

    Research started with treating industrial waste water produced by gold smelting with electro-catalytic oxidation process, during which the influences of chloride ion mass concentration, plate clearance and current density on the removal of cyanide and ammonia nitrogen were analyzed. The result shows the optimal conditions for removing cyanide and ammonia nitrogen with electro-catalytic oxidation process are like this; the initial pH of waste water 9. 28, initial chloride ion concentration 25 g/L, plate clearance 20 mm, current density 16.3 mA/cm2 , and waste water circulation velocity 64 mL/min. With the above conditions and electrolysis time 150 min,the cyanide concentration decreases from 28. 84 mg/L to 0. 20 mg/L,and ammonia nitrogen from 700 mg/L to 7 mg/L. The removal rate is respectively 99. 3 % and 99. 0 %. The cyanide and ammonia nitrogen concentration remained in the treated water has reached of Grade 1 requirements of Integrated waste water discharge standard ( GB 8978 - 1996). The power consumption per ton water is 13.1 kw·h.%对黄金冶炼废水进行了电催化氧化处理研究,考察了氯离子质量浓度、极板间距、电流密度等因素对氰化物和氨氮去除效果的影响.最佳工艺参数为:废水初始pH值9.28、氯离子初始质量浓度25 g/L、极板间距20 mm、电流密度16.3 mA/cm2、废水循环流速64 mL/min.在最佳工艺条件下,电解150 min,氰化物质量浓度从28.84 mg/L降至0.20 mg/L,氨氮质量浓度从700 mg/L降至7 mg/L,去除率分别为99.3%、99.0%,处理后废水中的总氰、氨氮均可达到《GB 8978-1996污水综合排放标准》一级标准.

  15. Distribution of ammonia oxidizers in relation to vegetation characteristics in the Qilian Mountains, northwestern China

    Science.gov (United States)

    Tai, X. S.; Mao, W. L.; Liu, G. X.; Chen, T.; Zhang, W.; Wu, X. K.; Long, H. Z.; Zhang, B. G.; Gao, T. P.

    2014-04-01

    Nitrogen is the major limiting nutrient in cold environments, and its availability is strongly dependent on nitrification. However, microbial communities driving this process remain largely uncharacterized in alpine meadow soils in northwestern China, namely those catalyzing the rate-limiting step of ammonia oxidation. In this study, ammonia-oxidizing communities in alpine meadow soils were characterized by real-time PCR and clone sequencing by targeting on amoA genes, which putatively encode ammonia monooxygenase subunit A. The results demonstrated that ammonia-oxidizing archaea (AOA) outnumbered ammonia-oxidizing bacteria (AOB) in the alpine meadow soils. Most of the AOA phylotypes detected in the study region fell within typical Group I.1b of Thaumarchaeota. Interestingly, a new ammonia-oxidizing archaeal group named "Kobresia meadow soil group" was found. Phylogenetic analysis of AOB communities exhibited a dominance of Nitrosospira-like sequences affiliated to beta-Proteobacteria. Compared with other alpine environments, Qilian Mountains had a great phylogenetic diversity of ammonia oxidizers. Principal Component Analysis (PCA) analysis showed that distinct AOA/AOB phylotype groups were attributed to different meadow types, reflecting an overall distribution of ammonia-oxidizing communities associated with meadow types. Redundancy Analysis (RDA) analysis showed that Axis 1 (90.9%) together with Axis 2 (9.1%) explained all the variables while Axis 1 exhibited a significant explanatory power. So that vegetation coverage mostly correlated to Axis 1 was the most powerful environmental factor in the study region. Characteristics of ammonia-oxidizing communities showed a close association with vegetation coverage.

  16. Real-Time, In Situ Sensor for Control of Ammonia Slip in SCR Installations

    Energy Technology Data Exchange (ETDEWEB)

    James Daly

    2005-09-30

    In this program, we proposed to demonstrate a compact, rugged, low-cost ammonia sensor with better than {+-}0.2 ppmv lower detection limit and resolution. Extensive design and trade studies indicated that this measurement could be made by exploiting the infrared absorbance of ammonia at 1527 nm to determine concentration. Key features of the design were (1) a electronically-tunable, wavelength-agile diode laser-pumped fiber laser, (2) a unique, low-cost folded path optical cell, and (3) an InGaAs photodiode (light detector). The sensor would be designed to make in situ measurements of ammonia in flue gas just downstream from the catalyst. The design proved robust and was able to operate at pressures in the range 1-3 atm and temperatures up to 500 C. With extensive signal processing, the sensor was able to make unambiguous ammonia measurements. But the signal processing degraded response time to almost 3 seconds and the measurement ambient conditions limited achievable resolution to about 20 ppmv ammonia. Extensive re-design, including a much longer optical path length and more robust real-time signal processing would be required to make sub-ppm measurements using this approach. During the performance period of this project, conventional in-situ laser based monitors and thick film ceramic ammonia sensors have been introduced and have gained acceptance in real-time feed-forward control for this application.

  17. Gold cementation with zinc powder from leaching solutions with ammonia-thiosulphate; Cementacion de oro con polvo de cinc en soluciones de lixiviacion coon amoniaco-tiosulfato

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, P.; Vargas, C.; Alvarez, R.; Alguacil, F. J.

    2005-07-01

    The cementation of gold with powder of zinc, from solutions with thiosulphate and ammonia, was studied. the variables evaluated were: thiosulphate concentration, ammonia concentration, pH, copper concentration and zinc concentration. the results have revealed the great importance of ammonia/thiosulphate relationship in this process and that the impurities presence like copper and zinc will to inhibit the cementation process. (Author) 16 refs.

  18. Effect of electromagnetic vibration on the microstructure of direct chill cast Al-Zn-Mg-Cu alloy

    Science.gov (United States)

    Zuo, Y.; Fu, X.; Zhu, Q.; Li, L.; Wang, P.; Cui, J.

    2016-03-01

    An electromagnetic vibration was achieved by the combined application of an alternating magnetic field and a stationary magnetic field during direct chill (DC) casting process. The ingots with 200 mm in diameter were prepared under the influence of electromagnetic vibration. The effect of electromagnetic vibration on the microstructure of an Al-Zn-Mg-Cu alloy was studied. The results showed that electromagnetic vibration has a significant effect on the solidification behaviour, under the influence of electromagnetic vibration during DC casting process, the microstructure is significantly refined and the uniformity of microstructure is evidently improved. This paper introduces the DC casting technology with the application of electromagnetic vibration, presents these results and gives corresponding discussions.

  19. Thermal sensitivity of excitation-contraction-coupling in a chill susceptible insect, Locusta migratoria

    DEFF Research Database (Denmark)

    Findsen, Anders; Pedersen, Thomas Holm; Overgaard, Johannes

    Many insect species enter a state of neuromuscular paralysis when their body temperature is lowered to a critical limit but the physiological and cellular processes underlying this chill coma are largely unknown. Previous studies on locusts show that muscle force production is highly depressed...... at low temperature implicating impairment in cellular mechanism in the muscle per se. Aiming to determine these mechanisms we examined the thermal sensitivity of several events in the excitation-contraction-coupling process including: i) Passive membrane properties and propagation of electrical signals......; ii) Intracellular Ca2+ regulation during muscle stimulation and iii) Ca2+-affinity/sensitivity and maximum force of the contractile proteins. Thus far the data show that low temperature resulted in a marked depolarization of resting membrane potential, but had negligible effects on the passive...

  20. Exploration Test on Gold Extraction from Arsenopyrite Gold Concentrate with Oxidation Pressure Leaching Process in Ammonium Thiocyanate-Ammonia System%某毒砂金矿硫氰酸盐氨性体系加压氧化提金探索试验

    Institute of Scientific and Technical Information of China (English)

    胡燕清; 杨声海; 陈永明

    2012-01-01

    对某毒砂金矿进行了硫氰酸盐氨性体系氧压提取金的探索试验,考察了反应温度、Cu2+浓度、浸出时间、液固比、氨水浓度、氧分压和硫氰酸铵浓度等对金浸出率的影响.结果表明,在下述优化条件下金浸出率为61.7%,即硫氰酸铵浓度3 mol/L,液固比5:1,反应温度150℃,浸出时间6h,搅拌速度750r/min,氨水浓度4.64 mo/L,铜加入量1.5 g/L.而经400℃焙烧预处理后金浸出率达到86.2%.%The exploration test on gold extraction from arsenopyrite gold concentrate with oxidation pressure leaching process in ammonium thiocyanate-ammonia system was performed. The effects of leaching temperature,copper concentration, leaching time, ratio of liquid to solid (L/S), ammonia concentration, oxygen pressure, and the concentration of ammonium thiocyanate on gold leaching rate were studied. The results show that the gold leaching ratio is 61. 7% under the optimum conditions including NH4SCN concentration of 3 mol/L, L/S=5, leaching temperature of 150 °C , leaching time of 6 hours, stirring speed of 750 r/min, ammonia concentration of 4. 64 mol/L, and copper dosage of 1. 5 g/L. The gold leaching ratio can leach 86. 2% after the pretreatment of roasting at 400℃.

  1. Resveratrol prevents ammonia toxicity in astroglial cells.

    Directory of Open Access Journals (Sweden)

    Larissa Daniele Bobermin

    Full Text Available Ammonia is implicated as a neurotoxin in brain metabolic disorders associated with hyperammonemia. Acute ammonia toxicity can be mediated by an excitotoxic mechanism, oxidative stress and nitric oxide (NO production. Astrocytes interact with neurons, providing metabolic support and protecting against oxidative stress and excitotoxicity. Astrocytes also convert excess ammonia and glutamate into glutamine via glutamine synthetase (GS. Resveratrol, a polyphenol found in grapes and red wines, exhibits antioxidant and anti-inflammatory properties and modulates glial functions, such as glutamate metabolism. We investigated the effect of resveratrol on the production of reactive oxygen species (ROS, GS activity, S100B secretion, TNF-α, IL-1β and IL-6 levels in astroglial cells exposed to ammonia. Ammonia induced oxidative stress, decreased GS activity and increased cytokines release, probably by a mechanism dependent on protein kinase A (PKA and extracellular signal-regulated kinase (ERK pathways. Resveratrol prevented ammonia toxicity by modulating oxidative stress, glial and inflammatory responses. The ERK and nuclear factor-κB (NF-κB are involved in the protective effect of resveratrol on cytokines proinflammatory release. In contrast, other antioxidants (e.g., ascorbic acid and trolox were not effective against hyperammonemia. Thus, resveratrol could be used to protect against ammonia-induced neurotoxicity.

  2. Ammonia synthesis using magnetic induction method (MIM)

    Science.gov (United States)

    Puspitasari, P.; Razak, J. Abd; Yahya, N.

    2012-09-01

    The most challenging issues for ammonia synthesis is to get the high yield. New approach of ammonia synthesis by using Magnetic Induction Method (MIM) and the Helmholtz Coils has been proposed. The ammonia detection was done by using Kjeldahl Method and FTIR. The system was designed by using Autocad software. The magnetic field of MIM was vary from 100mT-200mT and the magnetic field for the Helmholtz coils was 14mT. The FTIR result shows that ammonia has been successfully formed at stretching peaks 1097,1119,1162,1236, 1377, and 1464 cm-1. UV-VIS result shows the ammonia bond at 195nm of wavelength. The ammonia yield was increase to 244.72μmole/g.h by using the MIM and six pairs of Helmholtz coils. Therefore this new method will be a new promising method to achieve the high yield ammonia at ambient condition (at 25δC and 1atm), under the Magnetic Induction Method (MIM).

  3. Impact of Physical-Chemical Properties on Ammonia Emissions of Dairy Manure

    Science.gov (United States)

    Koirala, K.

    2015-12-01

    Ammonia emission is a major concern due to its adverse effects on animal and human health. Ionic strength and suspended solids play key roles in the ammonia volatilization process. These two parameters, however, are usually lumped together in form of totalsolids. The objective of this study was to separate the contribution of suspended solids (SS) from that of ionic strength (IS) on ammonia volatilization in liquid dairy manure. A two-way factorial experiment was conducted to simultaneously test the effects of IS and SS on ammonium dissociation: a key element of the ammonia volatilization process. The fraction of ammonia (β) in total ammoniacal nitrogen (TAN) was experimentally determined in a convective emission chamber, for each level of SS and IS, at a constant wind speed of 1.5 m s-1, and air and liquid temperature of 25°C. The two way analysis of variance showed a significant effect of SS concentration (p = 0.04) on fraction of ammonia in the liquid dairy manure, while the effect of ionic strength was marginal (p = 0.05). The highest dissociation of ammonium was observed in manure with the lowest SS concentration (0%) and the lowest ionic strength (0.10 mol L-1). Significant increases in suspended solids concentration and ionic strength were necessary to influence the ammonium dissociation in dairy manure. Results revealed that substantially high content of suspended solids (> 3.0%) or relatively high dilution of manure with water (30%) were necessary for these two parameters to play significant rolesin the ammonia volatilization mechanism in liquid dairy manure. Results also showed that the β was more sensitive to the changes in suspended solids concentration than in the changes in ionic strength within the ranges of SS and IS examined in this study.Overall, the SS and IS effects on ammonium dissociation (and by extension on ammonia volatilization process) were thus found negligible within the normal ranges of liquid dairy manure characteristics.

  4. Delineating Effects of Ionic Strength and Suspended Solids on Ammonia Volatilization from Dairy Manure Slurry

    Science.gov (United States)

    Koirala, K.

    2014-12-01

    Ammonia emission is a major concern due to its adverse effects on animal and human health. Ionic strength and suspended solids play key roles in the ammonia volatilization process. These two parameters, however, are usually lumped together in form of total solids. The objective of this study was to separate the contribution of suspended solids (SS) from that of ionic strength (IS) on ammonia volatilization in liquid dairy manure. A two-way factorial experiment was conducted to simultaneously test the effects of IS and SS on ammonium dissociation: a key element of the ammonia volatilization process. The fraction of ammonia (β) in total ammoniacal nitrogen (TAN) was experimentally determined in a convective emission chamber, for each level of SS and IS, at a constant wind speed of 1.5 m s-1, and air and liquid temperature of 25°C. The two way analysis of variance showed a significant effect of SS concentration (p = 0.04) on fraction of ammonia in the liquid dairy manure, while the effect of ionic strength was marginal (p = 0.05). The highest dissociation of ammonium was observed in manure with the lowest SS concentration (0%) and the lowest ionic strength (0.10 mol L-1). Significant increases in suspended solids concentration and ionic strength were necessary to influence the ammonium dissociation in dairy manure. Results revealed that substantially high content of suspended solids (> 3.0%) or relatively high dilution of manure with water (30%) were necessary for these two parameters to play significant roles in the ammonia volatilization mechanism in liquid dairy manure. Results also showed that the β was more sensitive to the changes in suspended solids concentration than in the changes in ionic strength within the ranges of SS and IS examined in this study. Overall, the SS and IS effects on ammonium dissociation (and by extension on ammonia volatilization process) were thus found negligible within the normal ranges of liquid dairy manure characteristics.

  5. OXIDATIVE STABILITY OF CHILLED CHICKEN MEAT AFTER FEEDING OF SELECTED PLANTS

    Directory of Open Access Journals (Sweden)

    Mária Martonová

    2010-07-01

    Full Text Available  The effect of feeding of lemon balm (Melissa officinalis, L and combination of yarrow (Achillea millefolium L and hawthorn (Crataegus oxyacantha L on oxidative stability and sensory properties of produced poultry meat was investigated. Sixty one-day-old commercial broiler chicks (ROSS 308 were used in our experiment, divided into 3 groups, and fed 41 days, as follows: control (K was fed with standard diet without supplementation of plants; second group (M was fed with standard diet supplemented with grounded lemon balm in concentration 2 % per 1 kg; and third group was fed with standard diet supplemented with grounded yarrow (2 % and hawthorn (1 %. Results showed that supplementation with lemon balm, and mainly combination of yarrow and hawthorn in the diet significantly caused reduction of lipid oxidation processes in thigh meat during chilling storage of samples. In addition, supplementation of plants in the diet had positive effect on sensory quality of meat of broiler chickens.    doi:10.5219/38 

  6. A Direct Numerical Simulation of Axisymmetric Cryogenic Chill Down in a Pipe in Microgravity

    Science.gov (United States)

    Agarwal, Alpana; Chung, J. N.

    2015-05-01

    Cryogenic two-phase flow with phase change heat transfer, consisting of a saturated liquid slug translating in its own superheated vapor in a circular pipe, was numerically simulated. The cryogenic chill down process was simplified by assuming ideal inverted annular flow regime. The method used is based on a sharp interface concept and developed on an Eulerian Cartesian fixed-grid with a cut-cell scheme and marker points to track the moving interface. The unsteady, axisymmetric Navier-Stokes equations in both liquid and vapor phases are solved separately and used to compute the velocity, pressure, and temperature fields and the deformation of the liquid core very accurately. Three most common cryogenic fluids, viz. nitrogen, oxygen, and argon were included in the study. The influence of non-dimensional parameters like Reynolds number Weber number , and Jakob number on flow characteristics was studied by systematically varying only one at a time. was found to affect the mass flow rates, but did not have a significant influence on the wall cooling or the Nusselt number. affected the interface shape at the leading edge of the liquid slug, also influencing the heat transfer and velocity field there. affects all three quantities of interest, i.e., mass flow rate, wall cooling, and the Nusselt number.

  7. Quality indicators and shelf life of red octopus (Octopus maya in chilling storage

    Directory of Open Access Journals (Sweden)

    Mariel GULLIAN-KLANIAN

    2016-01-01

    Full Text Available Abstract There are no precedents concerning the quality of Octopus maya during chilled storage. This study evaluated the shelf life of the red octopus in chilling storage (4oC and the correlation of the sensory quality index with microbiological counting and the biochemical indicators (hypoxanthine, histamine and volatile amines. A total of 112 whole raw octopi (average weight of 896 g were randomly selected from seven batches and exposed to 4°C for 18, 24, 48, 72, 84, 96, and 100 h. The histamine concentration (91.7%, followed by the counts of psychrotrophic bacteria (5.5% and hypoxanthine (2.2%, were the predictors from the redundancy analysis that better explained the changes taking place during the chilling hours. After 72 h of chilling, the microbial count was determined to be log 4.7 CFU/g, and the octopus samples were classified as B quality (minor sensory quality defects based on the sensory quality scale. Although the samples were not classified as unacceptable at 100 h of refrigeration by the sensory index, the level of histamine reached the defect action level (5 mg/100 g as ruled by the International Food Safety Authorities. The shelf life of the red octopus in chilling storage was predicted to be 119 h.

  8. Determination of Chilling and Heat Requirements of Pistachio (Pistacia vera L.) Cultivars

    Institute of Scientific and Technical Information of China (English)

    Majid Rahemi; Zahra Pakkish

    2009-01-01

    Determination of chilling and heat requirements of pistachio (Pistacia vera L.) cultivars is important for satisfactory growth and development, particularly when large-scale commercial production is desired. This experiment was conducted to determine chilling requirement inducing vegetative and flower buds of Kalle-Ghuchi, Owhadi, Ahmad-Ahgaei, and Akbari pistachio. Shoots with enough vegetative and flower buds were taken from pistachio trees during autumn 2007 and 2008 when temperature reached to≤15℃. Cuttings with flower buds were kept under (5±1)℃ for 0, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, 1200, 1250, and 1300 h, respectively, and cuttings with vegetative buds were kept at 51℃ until 1 500 h. The results indicated that pistachio eultivars requite chilling time between 750-1 400 h and heat requirements between 8 852-15 420 growing degree hours (GDH). Consequently, Kalle-Ghuehi had the lowest chilling (750-950 h), and heat (8 852-9 768 GDH) requirements, Ahmad-Aghaei and Owhadi had intermediate (1 000-1 250 h, 10 656-13 320 GDH) and Akbari had the highest chilling (1 200-1 400 h) and heat (11 863-15420 GDH) requirement.

  9. Effect of Polyamine Priming on Chilling Tolerance of Lolium perenne during Seed Imbibition

    Institute of Scientific and Technical Information of China (English)

    Yingfen WANG; Puchang WANG; Jiahai WU; Lili ZHAO; Bentian MO; Jun LI

    2012-01-01

    [Objective] This study aimed to investigate the effect of potyamine priming on physiological and biochemical variations of Lolium perenne embryos and seed germination. [Method] With annual Lolium perenne (Diamond T and Grazing-8000) as experimental materials, after priming with 0.5 mmol/L putrescine (Put), spermidine (Spd) and spermine (Spm) for 24 h and chilling imbibition at 5 ℃ for 12, 24, 36 and 48 h, the effect of Put, Spd and Spm priming on chilling tolerance and germination ability of annual Lolium perenne seeds during imbibition was investigated. [Result] Put, Spd and Spm priming improved the activities of peroxidase (POD), catalase (CAT), superoxide dismutase (SOD) and ascorbate peroxidase (APX) and content of soluble protein content under low temperature stress, significantly in-creased the germination rate, and shortened the average germination duration. After chilling imbibition for 48 h, compared with the control, the average germination rate of annual Lolium perenne seeds was improved by 15.5% and 12.0% after Put, Spd and Spm priming, and the average germination duration was shortened by 1.21 and 1.14 d. During seed imbibition, the chilling tolerance of Grazing-8000 was stronger than that of Diamond T. Overall, Put, Spd and Spm treatment could increase the chilling tolerance of annual Lolium perenne seeds during imbibition, and improve the germination ability of seeds under low temperature stress. [Conclusion] Results of this study provided theoretical basis for the application of seed priming technology in the production of annual ryegrass.

  10. Quantitative Phosphoproteomics Reveals Signaling Mechanisms Associated with Rapid Cold Hardening in a Chill-Tolerant Fly.

    Science.gov (United States)

    Teets, Nicholas M; Denlinger, David L

    2016-08-01

    Rapid cold hardening (RCH) is a physiological adaptation in which brief chilling (minutes to hours) significantly enhances the cold tolerance of insects. RCH allows insects to cope with sudden cold snaps and diurnal variation in temperature, but the mechanistic basis of this rapid stress response is poorly understood. Here, we used phosphoproteomics to identify phosphorylation-mediated signaling events that are regulated by chilling that induces RCH. Phosphoproteomic changes were measured in both brain and fat bodies, two tissues that are essential for sensing cold and coordinating RCH at the organismal level. Tissues were chilled ex vivo, and changes in phosphoprotein abundance were measured using 2D electrophoresis coupled with Pro-Q diamond labeling of phosphoproteins followed by protein identification via LC-MS/MS. In both tissues, we observed an abundance of protein phosphorylation events in response to chilling. Some of the proteins regulated by RCH-inducing chilling include proteins involved in cytoskeletal reorganization, heat shock proteins, and proteins involved in the degradation of damaged cellular components via the proteasome and autophagosome. Our results suggest that phosphorylation-mediated signaling cascades are major drivers of RCH and enhance our mechanistic understanding of this complex phenotype. PMID:27362561

  11. Identification of Clathrate Hydrates, Hexagonal Ice, Cubic Ice, and Liquid Water in Simulations: the CHILL+ Algorithm.

    Science.gov (United States)

    Nguyen, Andrew H; Molinero, Valeria

    2015-07-23

    Clathrate hydrates and ice I are the most abundant crystals of water. The study of their nucleation, growth, and decomposition using molecular simulations requires an accurate and efficient algorithm that distinguishes water molecules that belong to each of these crystals and the liquid phase. Existing algorithms identify ice or clathrates, but not both. This poses a challenge for cases in which ice and hydrate coexist, such as in the synthesis of clathrates from ice and the formation of ice from clathrates during self-preservation of methane hydrates. Here we present an efficient algorithm for the identification of clathrate hydrates, hexagonal ice, cubic ice, and liquid water in molecular simulations. CHILL+ uses the number of staggered and eclipsed water-water bonds to identify water molecules in cubic ice, hexagonal ice, and clathrate hydrate. CHILL+ is an extension of CHILL (Moore et al. Phys. Chem. Chem. Phys. 2010, 12, 4124-4134), which identifies hexagonal and cubic ice but not clathrates. In addition to the identification of hydrates, CHILL+ significantly improves the detection of hexagonal ice up to its melting point. We validate the use of CHILL+ for the identification of stacking faults in ice and the nucleation and growth of clathrate hydrates. To our knowledge, this is the first algorithm that allows for the simultaneous identification of ice and clathrate hydrates, and it does so in a way that is competitive with respect to existing methods used to identify any of these crystals. PMID:25389702

  12. Competition for ammonia influences the structure of chemotrophic communities in geothermal springs.

    Science.gov (United States)

    Hamilton, Trinity L; Koonce, Evangeline; Howells, Alta; Havig, Jeff R; Jewell, Talia; de la Torre, José R; Peters, John W; Boyd, Eric S

    2014-01-01

    Source waters sampled from Perpetual Spouter hot spring (pH 7.03, 86.4°C), Yellowstone National Park, WY, have low concentrations of total ammonia, nitrite, and nitrate, suggesting nitrogen (N) limitation and/or tight coupling of N cycling processes. Dominant small-subunit rRNA sequences in Perpetual Spouter source sediments are closely affiliated with the ammonia-oxidizing archaeon "Candidatus Nitrosocaldus yellowstonii" and the putatively nitrogen-fixing (diazotrophic) bacterium Thermocrinis albus, respectively, suggesting that these populations may interact at the level of the bioavailable N pool, specifically, ammonia. This hypothesis was evaluated by using a combination of geochemical, physiological, and transcriptomic analyses of sediment microcosms. Amendment of microcosms with allylthiourea, an inhibitor of ammonia oxidation, decreased rates of acetylene reduction (a proxy for N2 fixation) and nitrite production (a proxy for ammonia oxidation) and decreased transcript levels of structural genes involved in both nitrogen fixation (nifH) and ammonia oxidation (amoA). In contrast, amendment of microcosms with ammonia stimulated nitrite production and increased amoA transcript levels while it suppressed rates of acetylene reduction and decreased nifH transcript levels. Sequencing of amplified nifH and amoA transcripts from native sediments, as well as microcosms, at 2 and 4 h postamendment, indicates that the dominant and responsive populations involved in ammonia oxidation and N2 fixation are closely affiliated with Ca. Nitrosocaldus yellowstonii and T. albus, respectively. Collectively, these results suggest that ammonia-oxidizing archaea, such as Ca. Nitrosocaldus yellowstonii, have an apparent affinity for ammonia that is higher than that of the diazotrophs present in this ecosystem. Depletion of the bioavailable N pool through the activity of ammonia-oxidizing archaea likely represents a strong selective pressure for the inclusion of organisms capable of

  13. Ammonia Sensing Behaviors of TiO2-PANI/PA6 Composite Nanofibers

    Directory of Open Access Journals (Sweden)

    Fenglin Huang

    2012-12-01

    Full Text Available Titanium dioxide-polyaniline/polyamide 6 (TiO2-PANI/PA6 composite nanofibers were prepared by in situ polymerization of aniline in the presence of PA6 nanofibers and a sputtering-deposition process with a high purity titanium sputtering target. TiO2-PANI/PA6 composite nanofibers and PANI/PA6 composite nanofibers were fabricated for ammonia gas sensing. The ammonia sensing behaviors of the sensors were examined at room temperature. All the results indicated that the ammonia sensing property of TiO2-PANI/PA6 composite nanofibers was superior to that of PANI/PA6 composite nanofibers. TiO2-PANI/PA6 composite nanofibers had good selectivity to ammonia. It was also found that the content of TiO2 had a great influence on both the morphology and the sensing property of TiO2-PANI/PA6 composite nanofibers.

  14. Ammonia Nitrogen Transformations in a Reactor with Aggregate made of Sewage Sludge Combustion Fly Ash.

    Science.gov (United States)

    Rodziewicz, Joanna; Mielcarek, Artur; Janczukowicz, Wojciech; Białowiec, Andrzej; Gotkowska-Płachta, Anna; Proniewicz, Marcin

    2016-08-01

    The influence of light weight aggregate made of fly ash from sewage sludge thermal treatment (FASSTT LWA) on ammonia nitrogen metabolism, and on quantitative and qualitative changes of microorganisms colonizing the filling, was investigated. Two reactors were used in the experiment. The first was filled with gravel, the other with FASSTT LWA. The reactors were operated with a wastewater hydraulic loading rate of 5 mm(3) mm(-2) d(-1). During the eleven-week experiment, high efficiency of ammonia removal was observed. The lower concentrations of nitrites and nitrates in the effluent indicate that ammonia nitrogen removal resulted not just from nitrification. Nitrate concentration increase was reflected in a decrease in nitrogen removal efficiency. One possible explanation for this phenomenon is that in the period when ammonia nitrogen and nitrites were present in the reactor's FASSTT LWA filling, facilitating conditions occurred for the deammonification process. PMID:27456142

  15. Bromocresol Green/Mesoporous Silica Adsorbent for Ammonia Gas Sensing via an Optical Sensing Instrument

    Directory of Open Access Journals (Sweden)

    Chun-Nan Kuo

    2011-04-01

    Full Text Available A meso-structured Al-MCM-41 material was impregnated with bromocresol green (BG dye and then incorporated into a UV-Vis DRA spectroscopic instrument for the online detection of ammonia gas. The absorption response of the Al-MCM-41/BG ammonia sensing material was very sensitive at the optical absorption wavelength of 630 nm. A high linear correlation was achieved for ppmv and sub-ppmv levels of ammonia gas. The response time for the quantitative detection of ammonia gas concentrations ranging from 0.25 to 2.0 ppmv was only a few minutes. The lower detection limit achieved was 0.185 ppmv. The color change process was fully reversible during tens of cycling tests. These features together make this mesoporous Al-MCM-41 material very promising for optical sensing applications.

  16. Bromocresol green/mesoporous silica adsorbent for ammonia gas sensing via an optical sensing instrument.

    Science.gov (United States)

    Chang, Yu-Chang; Bai, Hsunling; Li, Shou-Nan; Kuo, Chun-Nan

    2011-01-01

    A meso-structured Al-MCM-41 material was impregnated with bromocresol green (BG) dye and then incorporated into a UV-Vis DRA spectroscopic instrument for the online detection of ammonia gas. The absorption response of the Al-MCM-41/BG ammonia sensing material was very sensitive at the optical absorption wavelength of 630 nm. A high linear correlation was achieved for ppmv and sub-ppmv levels of ammonia gas. The response time for the quantitative detection of ammonia gas concentrations ranging from 0.25 to 2.0 ppmv was only a few minutes. The lower detection limit achieved was 0.185 ppmv. The color change process was fully reversible during tens of cycling tests. These features together make this mesoporous Al-MCM-41 material very promising for optical sensing applications.

  17. Ammonia sensing behaviors of TiO2-PANI/PA6 composite nanofibers.

    Science.gov (United States)

    Wang, Qingqing; Dong, Xianjun; Pang, Zengyuan; Du, Yuanzhi; Xia, Xin; Wei, Qufu; Huang, Fenglin

    2012-01-01

    Titanium dioxide-polyaniline/polyamide 6 (TiO(2)-PANI/PA6) composite nanofibers were prepared by in situ polymerization of aniline in the presence of PA6 nanofibers and a sputtering-deposition process with a high purity titanium sputtering target. TiO(2)-PANI/PA6 composite nanofibers and PANI/PA6 composite nanofibers were fabricated for ammonia gas sensing. The ammonia sensing behaviors of the sensors were examined at room temperature. All the results indicated that the ammonia sensing property of TiO(2)-PANI/PA6 composite nanofibers was superior to that of PANI/PA6 composite nanofibers. TiO(2)-PANI/PA6 composite nanofibers had good selectivity to ammonia. It was also found that the content of TiO(2) had a great influence on both the morphology and the sensing property of TiO(2)-PANI/PA6 composite nanofibers. PMID:23235446

  18. Effect of ammonia on hydrogenotrophic methanogens and syntrophic acetate oxidizing bacteria

    DEFF Research Database (Denmark)

    Wang, Han; Fotidis, Ioannis; Angelidaki, Irini

    2015-01-01

    methanogens. Two pure strains of hydrogenotrophic methanogens (i.e: Methanoculleus bourgensis and Methanoculleus thermophiles) and two pure strains of SAO bacteria (i.e: Tepidanaerobacter acetatoxydans and Thermacetogenium phaeum) were inoculated under four different ammonia (0.26, 3, 5 and 7g NH4+-N...... compared to the hydrogenotrophic methanogens tested. Thus, it seems that hydrogenotrophic methanogens could be equally, if not more, tolerant to high ammonia levels compared to SAO bacteria.......Substrates that contain high ammonia levels can cause inhibition on anaerobic digestion process and unstable biogas production. The aim of the current study was to assess the effects of different ammonia levels on pure strains of (syntrophic acetate oxidizing) SAO bacteria and hydrogenotrophic...

  19. The role of ammonia in sulfuric acid ion induced nucleation

    Directory of Open Access Journals (Sweden)

    I. K. Ortega

    2008-06-01

    Full Text Available We have developed a new multi-step strategy for quantum chemical calculations on atmospherically relevant cluster structures that makes calculation for large clusters affordable with a good accuracy-to-computational effort ratio. We have applied this strategy to evaluate the relevance of ternary ion induced nucleation; we have also performed calculations for neutral ternary nucleation for comparison. The results for neutral ternary nucleation agree with previous results, and confirm the important role of ammonia in enhancing the growth of sulfuric acid clusters. On the other hand, we have found that ammonia does not enhance the growth of ionic sulfuric acid clusters. The results also confirm that ion-induced nucleation is a barrierless process at high altitudes, but at ground level there exists a barrier due to the presence of a local minimum on the free energy surface.

  20. Porous Materials for Hydrolytic Dehydrogenation of Ammonia Borane

    Directory of Open Access Journals (Sweden)

    Tetsuo Umegaki

    2015-07-01

    Full Text Available Hydrogen storage is still one of the most significant issues hindering the development of a “hydrogen energy economy”. Ammonia borane is notable for its high hydrogen densities. For the material, one of the main challenges is to release efficiently the maximum amount of the stored hydrogen. Hydrolysis reaction is a promising process by which hydrogen can be easily generated from this compound. High purity hydrogen from this compound can be evolved in the presence of solid acid or metal based catalyst. The reaction performance depends on the morphology and/or structure of these materials. In this review, we survey the research on nanostructured materials, especially porous materials for hydrogen generation from hydrolysis of ammonia borane.