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Sample records for catalytic-ifp ammonia scrubbing process

  1. 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.

  2. 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.

  3. Acid wash scrubbing as a countermeasure for ammonia emissions from a postcombustion CO2 Capture Plant

    NARCIS (Netherlands)

    Khakharia, P.M.; Huizinga, A.; Jurado Lopez, C.; Sanchez Sanchez, C.; Miguel Mercader, F. de; Vlugt, T.J.H.; Goetheer, E.L.V.

    2014-01-01

    Amine-based absorption-desorption processes are considered to be the state-of-the-art technology for CO2 capture. However, the typical amines used are susceptible to oxidative and thermal degradation. Ammonia is formed as a result of oxidative solvent degradation. Because of the volatility of ammoni

  4. Processing device with self-scrubbing logic

    Science.gov (United States)

    Wojahn, Christopher K.

    2016-03-01

    An apparatus includes a processing unit including a configuration memory and self-scrubber logic coupled to read the configuration memory to detect compromised data stored in the configuration memory. The apparatus also includes a watchdog unit external to the processing unit and coupled to the self-scrubber logic to detect a failure in the self-scrubber logic. The watchdog unit is coupled to the processing unit to selectively reset the processing unit in response to detecting the failure in the self-scrubber logic. The apparatus also includes an external memory external to the processing unit and coupled to send configuration data to the configuration memory in response to a data feed signal outputted by the self-scrubber logic.

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

    International Nuclear Information System (INIS)

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

  6. 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...... 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...

  7. 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...

  8. Wastewater centrate ammonia removal by chemisorption processes

    International Nuclear Information System (INIS)

    'Full text:' This presentation will describe the nature, scope, and findings of a third-party evaluation of a patent-protected wastewater treatment technology identified as the ThermoEnergy Ammonia Recovery Process TM (ARP). The ARP is a reversible chemisorption process using a zinc-impregnated ion exchange resin, and it is unique in that it removes/reduces the ammonia-nitrogen load in the solids processing liquor of municipal sewage treatment plants and recycles the recovered product into a pelletized ammonium salt that can be used as an agricultural fertilizer. The primary objective of the ARP evaluation was to perform well-defined field and laboratory tests to provide data on process performance. The evaluation process was overseen and coordinated by the Environmental Technology Evaluation Center (EvTEC), a program of the Civil Engineering Research Foundation (CERF), the research and technology transfer arm of the American Society of Civil Engineers (ASCE). EvTEC is a pilot program evaluating innovative environmental technologies under the US Environmental Protection Agency's (USEPA) Environmental Technology Verification (ETV) Program. A pilot scale ARP treatment facility was constructed and tested at the Oakwood Beach Water Pollution Control Plant (WPCP) in Staten Island, New York, from September through December of 1998. While operating during the 3 month period using the anaerobically digested centrate normally produced at the WPCP, the pilot study demonstrated that the ARP process was capable of removing/recovering ammonia with efficiencies ranging from 75-99+ % at influent concentrations exceeding 400 mg/L. During the pilot plant operations, forty-eight (48) complete validated runs of centrate processing were performed. The plant processed the centrate under normal day-to-day conditions at the WPCP, and no special operational considerations were given to the centrifuge operation to accommodate the ARP pilot plant. The Oakwood WPCP operated exactly the way

  9. Integration of a Water Scrubbing Technique and Two-Stage Pressurized Anaerobic Digestion in One Process

    OpenAIRE

    Andreas Lemmer; Yuling Chen; Anna-Maria Wonneberger; Frank Graf; Rainer Reimert

    2015-01-01

    Two-stage pressurized anaerobic digestion is a promising technology. This technology integrates in one process biogas production with upgrading and pressure boosting for grid injection. To investigate whether the efficiency of this novel system could be further increased, a water scrubbing system was integrated into the methanogensis step. Therefore, six leach-bed reactors were used for hydrolysis/acidification and a 30-L pressurized anaerobic filter operated at 9 bar was adopted for acetogen...

  10. A Markov decision process for managing habitat for Florida scrub-jays

    Science.gov (United States)

    Johnson, Fred A.; Breininger, David R.; Duncan, Brean W.; Nichols, James D.; Runge, Michael C.; Williams, B. Ken

    2011-01-01

    Florida scrub-jays Aphelocoma coerulescens are listed as threatened under the Endangered Species Act due to loss and degradation of scrub habitat. This study concerned the development of an optimal strategy for the restoration and management of scrub habitat at Merritt Island National Wildlife Refuge, which contains one of the few remaining large populations of scrub-jays in Florida. There are documented differences in the reproductive and survival rates of scrubjays among discrete classes of scrub height (management strategy that would maximize the long-term growth rate of the resident scrub-jay population. We used aerial imagery with multistate Markov models to estimate annual transition probabilities among the four scrub-height classes under three possible management actions: scrub restoration (mechanical cutting followed by burning), a prescribed burn, or no intervention. A strategy prescribing the optimal management action for management units exhibiting different proportions of scrub-height classes was derived using dynamic programming. Scrub restoration was the optimal management action only in units dominated by mixed and tall scrub, and burning tended to be the optimal action for intermediate levels of short scrub. The optimal action was to do nothing when the amount of short scrub was greater than 30%, because short scrub mostly transitions to optimal height scrub (i.e., that state with the highest demographic success of scrub-jays) in the absence of intervention. Monte Carlo simulation of the optimal policy suggested that some form of management would be required every year. We note, however, that estimates of scrub-height transition probabilities were subject to several sources of uncertainty, and so we explored the management implications of alternative sets of transition probabilities. Generally, our analysis demonstrated the difficulty of managing for a species that requires midsuccessional habitat, and suggests that innovative management tools may

  11. Production of adsorbent from palm shell for radioactive iodine scrubbing process

    International Nuclear Information System (INIS)

    The biggest biomass source in Malaysia comes from oil palm industry. According to the statistic of year 2004, Malaysia produced 40 million tones per year of biomass which 30 million tones of biomass originated from the oil palm industries. Therefore, the biomass waste such as palm kernel shell can be used to produce granular adsorbent for radioactive materials. For that reason, a newly system, called Rocking Kiln - Fluidized Bed (RK - FB) was developed to utilize large amount of the biomass to produce high value added product. Charcoal or chemically produced activated carbon could be produced by using the kiln. Washing process was introduced to remove particles, minerals and volatile matters from charcoal produced and then would create more surface area in the adsorbent by creating more active sites. In this research, the adsorbent produced was used to scrub iodine 131. In nuclear power reactor, iodine isotope 131 is produced during nuclear fission, and this elementary radioactive iodine may pollute exhaust air streams that could cause thyroid cancer. For removal of radioactive iodine, normally a potassium iodide - impregnated activated carbon (KI - AC) is used. Thus, a process will be developed to produce KI - AC and this product will be used to calculate the efficiency to remove the radioactive iodine 131.The results obtain show that adsorbent produced has a high potential to be used in radioactive adsorbing and likely more economics. This paper will elaborate further the experimental set-up of in Kiln - Fluidized Bed (RK - FB), adsorbent quality and radioactive scrubbing process. (author)

  12. 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.

  13. Scrub typhus

    Directory of Open Access Journals (Sweden)

    Amy G Rapsang

    2013-01-01

    Full Text Available Scrub typhus is an acute febrile illness caused by orientia tsutsugamushi, transmitted to humans by the bite of the larva of trombiculid mites. It causes a disseminated vasculitic and perivascular inflammatory lesions resulting in significant vascular leakage and end-organ injury. It affects people of all ages and even though scrub typhus in pregnancy is uncommon, it is associated with increased foetal loss, preterm delivery, and small for gestational age infants. After an incubation period of 6-21 days, onset is characterized by fever, headache, myalgia, cough, and gastrointestinal symptoms. A primary papular lesion which later crusts to form a flat black eschar, may be present. If untreated, serious complications may occur involving various organs. Laboratory studies usually reveal leukopenia, thrombocytopenia, deranged hepatic and renal function, proteinuria and reticulonodular infiltrate. Owing to the potential for severe complications, diagnosis, and decision to initiate treatment should be based on clinical suspicion and confirmed by serologic tests. A therapeutic trial of tetracycline or chloramphenicol is indicated in patients in whom the diagnosis of scrub typhus is suspected. The recommended treatment regimen for scrub typhus is doxycycline. Alternative regimens include tetracycline, chloramphenicol, azithromycin, ciprofloxacin, rifampicin, and roxithromycin. Treatment of pregnant women with azithromycin was successfully done without relapse and with favorable pregnancy outcomes. Hence, early diagnosis and treatment are essential in order to reduce the mortality and the complications associated with the disease. We searched the English-language literature for reports of scrub typhus in children, pregnant women, and non-pregnant patients with scrub typhus, using the MEDLINE/PubMed database, which includes citations from 1945 to the present time. We used the search terms ′scrub typhus′, ′scrub typhus′ and ′pregnancy′, ′scrub

  14. 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 ...

  15. Integration of a Water Scrubbing Technique and Two-Stage Pressurized Anaerobic Digestion in One Process

    Directory of Open Access Journals (Sweden)

    Andreas Lemmer

    2015-03-01

    Full Text Available Two-stage pressurized anaerobic digestion is a promising technology. This technology integrates in one process biogas production with upgrading and pressure boosting for grid injection. To investigate whether the efficiency of this novel system could be further increased, a water scrubbing system was integrated into the methanogensis step. Therefore, six leach-bed reactors were used for hydrolysis/acidification and a 30-L pressurized anaerobic filter operated at 9 bar was adopted for acetogenesis/methanogenesis. The fermentation liquid of the pressurized anaerobic filter was circulated periodically via a flash tank, operating at atmospheric pressure. Due to the pressure drop, part of dissolved carbon dioxide was released from the liquid phase into the flash tank. The depressurized fermentation liquid was then recycled to the pressurized reactor. Three different flow rates (0 L·day−1, 20 L·day−1 and 40 L·day−1 were tested with three repetitions. As the daily recycled flashed liquid flow was increased from 0 to 40 L, six times as much as the daily feeding, the methane content in the biogas increased from 75 molar percent (mol% to 87 mol%. The pH value of the substrate in the methane reactor rose simultaneously from 6.5 to 6.7. The experimental data were verified by calculation.

  16. 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...

  17. Summary of INCO corrosion tests in power plant flue gas scrubbing processes

    International Nuclear Information System (INIS)

    Corrosion tests in a number of flue-gas desulfurization units have shown that carbon steel, low alloy steels, and Type 304L stainless steel are inadequate in the wet portions of the scrubbers. Type 316L stainless steel is sometimes subject to localized corrosive attack in scrubber environments with certain combinations of pH and chloride content. A corollary is that corrosion of Type 316L stainless steel might be controlled by control of scrubbing media pH and chloride content. Although an attempt was made to correlate the pitting and crevice corrosion obtained on the Type 316 stainless steel test samples with chloride and pH measurements, relatively wide scatter in the data indicated only a modest correlation. This is attributed to variations in local conditions, especially beneath deposits, that differ from the liquor samples obtained for analysis, to processing upsets, to temperature differences, and to some extent to inaccuracies in measurement of pH and chloride levels. The data do show, however, that molybdenum as an alloying element in stainless steels and high nickel alloys was very beneficial in conferring resistance to localized attack in scrubber environments. High nickel alloys containing appreciable amounts of molybdenum such as Hastelloy alloy C-276 and Inconel alloy 625 can be used for critical components. Chloride stress corrosion cracking (SCC) of austenitic stainless steels has generally not been a problem in FGD scrubbers, apparently because operating temperatures are comparatively low. An exception is reheater tubing where some failures have occurred because of elevated temperatures in conjunction with condensate that forms during shut-down periods or carryover of chloride laden mist from the scrubber. This problem can be overcome by proper alloy selection or maintaining dry conditions

  18. Design and scale-up of an oxidative scrubbing process for the selective removal of hydrogen sulfide from biogas

    International Nuclear Information System (INIS)

    Highlights: ► Alkaline oxidative scrubbing proved for biogas desulfurization ► Effect of operating conditions on hydrogen sulfide removal efficiency. ► Minimization of caustic and oxidant consumption. ► Process control via pH, redox potential and conductivity measurement. ► Investigation of long-term behavior of pilot plant operation. - Abstract: Reliable and selective removal of hydrogen sulfide (H2S) is an essential part of the biogas upgrading procedure in order to obtain a marketable and competitive natural gas substitute for flexible utilization. A promising biogas desulfurization technology has to ensure high separation efficiency regardless of process conditions or H2S load without the use or production of toxic or ecologically harmful substances. Alkaline oxidative scrubbing is an interesting alternative to existing desulfurization technologies and is investigated in this work. In experiments on a stirred tank reactor and a continuous scrubbing column in laboratory-scale, H2S was absorbed from a gas stream containing large amounts of carbon dioxide (CO2) into an aqueous solution prepared from sodium hydroxide (NaOH), sodium bicarbonate (NaHCO3) and hydrogen peroxide (H2O2). The influence of pH, redox potential and solution aging on the absorption efficiency and the consumption of chemicals was investigated. Because of the irreversible oxidation reactions of dissolved H2S with H2O2, high H2S removal efficiencies were achieved while the CO2 absorption was kept low. At an existing biogas upgrading plant an industrial-scale pilot scrubber was constructed, which efficiently desulfurizes 180 m3/h of raw biogas with an average removal efficiency of 97%, even at relatively high and strongly fluctuating H2S contents in the crude gas.

  19. Combustion gas scrubbing system

    Energy Technology Data Exchange (ETDEWEB)

    Dahlstrom, D.A.; Ellison, W.; Wilhelm, J.H.

    1979-04-03

    In a cooperative combination of two scrubbing systems, the first scrubbing system operates upon combustion gases with an aqueous solution to remove hydrogen chloride gas and other chlorine components. The second scrubbing system subsequently operates upon the combustion gases with a sodium-base solution to absorb sulfur oxides. The products of the two scrubbing systems are treated in combination to form a material for disposal and to generate the aqueous scrubbing solution for the chloride scrubbing system.

  20. Recovery of actinides from TBP-Na2Co3 scrub-waste solutions: the ARALEX process

    International Nuclear Information System (INIS)

    A flowsheet for the recovery of actinides from TBP-Na2CO3 scrub-waste solutions has been developed, based on batch extraction data, and tested, using laboratory-scale countercurrent extraction techniques. The process, called the ARALEX process, uses 2-ethyl-1-hexanol (2-EHOH) to extract the TBP degradation products (HDBP and H2MBP) from acidified Na2CO3 scrub waste leaving the actinides in the aqueous phase. Dibutyl and monobutyl phosphoric acids are attached to the 2-EHOH molecules through hydrogen bonds, which also diminish the ability of the HDBP and H2MBP to complex actinides. Thus all actinides remain in the aqueous raffinate. Dilute sodium hydroxide solutions can be used to back-extract the dibutyl and monobutyl phosphoric acid esters as their sodium salts. The 2-EHOH can then be recycled. After extraction of the acidified carbonate waste with 2-EHOH, the actinides may be readily extracted from the raffinate with DHDECMP or, in the case of tetra- and hexavalent actinides, with TBP. The ARALEX process can also be applied to other actinide waste streams which contain appreciable concentrations of polar organic compounds (e.g., detergents) that interfere with conventional actinide ion exchange and liquid-liquid extraction procedures. 20 figures, 6 tables

  1. Pool scrubbing

    International Nuclear Information System (INIS)

    The Source Term Project in the Third Frame Work Programme of the European Union Was conducted under and important joined effort on pool scrubbing research. CIEMAT was the Task Manager of the project and several other organizations participated in it: JRC-Ispra, NNC Limited, RUB-NES and UPM. The project was divided into several tasks. A peer review of the models in the pool scrubbing codes SPARC90 and BUSCA-AUG92 was made, considering the different aspects in the hydrodynamic phenomenology, particle retention and fission product vapor abortions. Several dominant risk accident sequences were analyzed with MAAP, SPARC90 and BUSCA-AUG92 codes, and the predictions were compared. A churn-turbulent model was developed for the hydrodynamic behaviour of the pool. Finally, an experimental programme in the PECA facility of CIEMAT was conducted in order to study the decontamination factor under jet injection regime, and the experimental observations were compared with the SPARC and BUSCA codes. (Author)

  2. Design and scale-up of an oxidative scrubbing process for the selective removal of hydrogen sulfide from biogas.

    Science.gov (United States)

    Krischan, J; Makaruk, A; Harasek, M

    2012-05-15

    Reliable and selective removal of hydrogen sulfide (H(2)S) is an essential part of the biogas upgrading procedure in order to obtain a marketable and competitive natural gas substitute for flexible utilization. A promising biogas desulfurization technology has to ensure high separation efficiency regardless of process conditions or H(2)S load without the use or production of toxic or ecologically harmful substances. Alkaline oxidative scrubbing is an interesting alternative to existing desulfurization technologies and is investigated in this work. In experiments on a stirred tank reactor and a continuous scrubbing column in laboratory-scale, H(2)S was absorbed from a gas stream containing large amounts of carbon dioxide (CO(2)) into an aqueous solution prepared from sodium hydroxide (NaOH), sodium bicarbonate (NaHCO(3)) and hydrogen peroxide (H(2)O(2)). The influence of pH, redox potential and solution aging on the absorption efficiency and the consumption of chemicals was investigated. Because of the irreversible oxidation reactions of dissolved H(2)S with H(2)O(2), high H(2)S removal efficiencies were achieved while the CO(2) absorption was kept low. At an existing biogas upgrading plant an industrial-scale pilot scrubber was constructed, which efficiently desulfurizes 180m(3)/h of raw biogas with an average removal efficiency of 97%, even at relatively high and strongly fluctuating H(2)S contents in the crude gas. PMID:22440540

  3. Process for reprocessing and regenerating wash water containing ammonia

    International Nuclear Information System (INIS)

    In order to produce nuclear fuels, an oxide hydrate gel is precipitated by hydrolysis from nitrate solutions of uranium, plutonium and thorium, which contains the rest of the precipitation chemicals and by-products of the reaction, which have to be removed before further processing. Apart from ammonium salts, the 2-3% solution of ammonia in water used as wash water contains small quantities of heavy metal salts after being used several times. The waste water containing ammonia is evaporated to a concentration of about 1000 g/litre and the vapour produced is washed with hot (above 1000C) 30% caustic soda solution before condensation, in order to prevent dissolving of oxide particles by wash water containing carbonate. The regenerate obtained in this way, which is now free of carbonate, can be used to wash the oxide hydrate gel out, after adding the ammonia. The soda solution produced in this washing out or the soda produced by drying is the only waste product of the process, apart from filter material. (PW)

  4. Design and scale-up of an oxidative scrubbing process for the selective removal of hydrogen sulfide from biogas

    Energy Technology Data Exchange (ETDEWEB)

    Krischan, J., E-mail: jutta_krischan@hotmail.com [Vienna University of Technology, Institute of Chemical Engineering, Getreidemarkt 9/166, 1060 Vienna (Austria); Makaruk, A., E-mail: aleksander.makaruk@tuwien.ac.at [Vienna University of Technology, Institute of Chemical Engineering, Getreidemarkt 9/166, 1060 Vienna (Austria); Harasek, M., E-mail: michael.harasek@tuwien.ac.at [Vienna University of Technology, Institute of Chemical Engineering, Getreidemarkt 9/166, 1060 Vienna (Austria)

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Alkaline oxidative scrubbing proved for biogas desulfurization Black-Right-Pointing-Pointer Effect of operating conditions on hydrogen sulfide removal efficiency. Black-Right-Pointing-Pointer Minimization of caustic and oxidant consumption. Black-Right-Pointing-Pointer Process control via pH, redox potential and conductivity measurement. Black-Right-Pointing-Pointer Investigation of long-term behavior of pilot plant operation. - Abstract: Reliable and selective removal of hydrogen sulfide (H{sub 2}S) is an essential part of the biogas upgrading procedure in order to obtain a marketable and competitive natural gas substitute for flexible utilization. A promising biogas desulfurization technology has to ensure high separation efficiency regardless of process conditions or H{sub 2}S load without the use or production of toxic or ecologically harmful substances. Alkaline oxidative scrubbing is an interesting alternative to existing desulfurization technologies and is investigated in this work. In experiments on a stirred tank reactor and a continuous scrubbing column in laboratory-scale, H{sub 2}S was absorbed from a gas stream containing large amounts of carbon dioxide (CO{sub 2}) into an aqueous solution prepared from sodium hydroxide (NaOH), sodium bicarbonate (NaHCO{sub 3}) and hydrogen peroxide (H{sub 2}O{sub 2}). The influence of pH, redox potential and solution aging on the absorption efficiency and the consumption of chemicals was investigated. Because of the irreversible oxidation reactions of dissolved H{sub 2}S with H{sub 2}O{sub 2}, high H{sub 2}S removal efficiencies were achieved while the CO{sub 2} absorption was kept low. At an existing biogas upgrading plant an industrial-scale pilot scrubber was constructed, which efficiently desulfurizes 180 m{sup 3}/h of raw biogas with an average removal efficiency of 97%, even at relatively high and strongly fluctuating H{sub 2}S contents in the crude gas.

  5. 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...

  6. 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

  7. Optimization of biomethanation focusing on high ammonia loaded processes

    DEFF Research Database (Denmark)

    Wang, Han

    players in the SAO pathway. Thirdly, based on the same idea (promoting the syntrophic acetate oxidation pathway to alleviate ammonia inhibition), the hypothesis of bioaugmentation with high ammonia tolerant methanogenic archaea could be a new practical solution for fast recovery from ammonia inhibition......) in mesophilic and thermophilic condition, respectively. For the reactors without adding hydrogen, the methane yield decreased 65.0% (mesophilic) and 44.2% (thermophilic) when ammonia level increased to 7 g NH4+-N L-1. The results demonstrated that the hydrogen assisted biogas production and upgrading...

  8. 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.

  9. Bubble scrub : process aims to reduce oil content and dispose of solids in produced water

    International Nuclear Information System (INIS)

    The oil and water separation processes used by the petroleum industry typically leave behind between 5000 and 30,000 parts per million of oil in its produced water. The water is then injected back into the ground or disposed of in tailings ponds. This article described a water-oil remediation technology designed to reduce the hydrocarbon content in injected water to less than 5 parts per million. The process used aeration in a tank configuration that injected gas into the produced water. The aeration process created micron-sized gas bubbles that super-saturated the produced water in order to break the oil-water interfaces. A prototype unit has been designed to process 1000 bbls per day of water-oil mixture and is currently being used by an Alberta producer. It was concluded that the new system will help to reduce the massive amounts of water used in oil sands production. 1 fig

  10. 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.

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

    Science.gov (United States)

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

    2013-09-01

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

  12. 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

  13. Technical and operational feasibility of psychrophilic anaerobic digestion biotechnology for processing ammonia-rich waste

    International Nuclear Information System (INIS)

    Highlights: • Long-term anaerobic digestion (AD) process at high-ammonia (>5 gN/L) is limited. • PADSBR technology was validated to treat N-rich waste with 8.2 ± 0.3 gNH3-N/L. • Excess ammonia (8.2 gN/L) did not affect the digestion process with no inhibition. • VFA, an indicator for process stability, did not accumulate in PADSBR. • Biomass acclimation in PADSBR ensured a high-stabilization of the AD process. - Abstract: Ammonia nitrogen plays a critical role in the performance and stability of anaerobic digestion (AD) of ammonia rich wastes like animal manure. Nevertheless, inhibition due to high ammonia remains an acute limitation in AD process. A successful long-term operation of AD process at high ammonia (>5 gN/L) is limited. This study focused on validating technical feasibility of psychrophilic AD in sequencing batch reactor (PADSBR) to treat swine manure spiked with NH4Cl up to 8.2 ± 0.3 gN/L, as a representative of N-rich waste. CODt, CODs, VS removals of 86 ± 3, 82 ± 2 and 73 ± 3% were attained at an OLR of 3 gCOD/L.d, respectively. High-ammonia had no effect on methane yields (0.23 ± 0.04 L CH4/gTCODfed) and comparable to that of control reactors, which fed with raw swine manure alone (5.5 gN/L). Longer solids/hydraulic retention times in PADSBRs enhanced biomass acclimation even at high-ammonia. Thus VFA, an indicator for process stability, did not accumulate in PADSBR. Further investigation is essential to establish the maximum concentrations of TKN and free ammonia that the PADSBR can sustain

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

    Energy Technology Data Exchange (ETDEWEB)

    Bordalo, V.; Da Silveira, E. F. [Departamento de Fisica/Laboratorio do Acelerador Van de Graaff, Pontificia Universidade Catolica do Rio de Janeiro, Rua Marques de S. Vicente 225, 22451-900 Rio de Janeiro, RJ (Brazil); Lv, X. Y.; Domaracka, A.; Rothard, H.; Boduch, P. [Centre de Recherche sur les Ions, les Materiaux et la Photonique (CEA/CNRS/ENSICAEN/Universite de Caen-Basse Normandie), CIMAP-CIRIL-GANIL, Boulevard Henri Becquerel, BP 5133, F-14070 Caen Cedex 05 (France); Seperuelo Duarte, E., E-mail: vbordalo@fis.puc-rio.br [Grupo de Fisica e Astronomia, Instituto Federal do Rio de Janeiro, Rua Lucio Tavares 1045, 26530-060 Nilopolis, RJ (Brazil)

    2013-09-10

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

  15. 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....... Additionally, for comparison purposes, a soluble carbohydrate (i.e. glucose) was also used as a co-substrate in an identical CSTR reactor (RGLU). At 5 g NH4+-N·L-1, relative methane production of RGTO and RGLU, was 10.5% and 41% compared to the expected uninhibited production, respectively. At the same time...

  16. 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.

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

    OpenAIRE

    Kim, Sung Bong; Lee, Sang Jun; Lee, Ju Hun; Jung, You Ree; Thapa, Laxmi Prasad; Kim, Jun Seok; Um, Youngsoon; Park, Chulhwan; Kim, Seung Wook

    2013-01-01

    Background Use of lignocellulosic biomass has received attention lately because it can be converted into various versatile chemical compounds by biological processes. In this study, a two-step pretreatment with dilute sulfuric acid and aqueous ammonia was performed efficiently on rice straw to obtain fermentable sugar. The soaking in aqueous ammonia process was also optimized by a statistical method. Results Response surface methodology was employed. The determination coefficient (R2) value w...

  18. Escrubagem da Bauxita de Paragominas - PA. parte 2: modelagem matemática Scrubbing Process of the Miltonia 3 Bauxite. part 2: mathematical modeling

    Directory of Open Access Journals (Sweden)

    Jaime Henrique Barbosa da Costa

    2012-12-01

    Full Text Available O objetivo desse trabalho foi desenvolver um modelo matemático empírico para a operação de escrubagem da bauxita proveniente da jazida Miltônia 3, da Mina de Bauxita de Paragominas-PA, com vistas a fornecer parâmetros para previsão de seu desempenho e otimização. O modelo foi desenvolvido a partir de dados gerados em uma campanha de experimentos de escrubagem, em um tambor desagregador de laboratório, tomando-se, como base, o planejamento fatorial. A variável de resposta selecionada foi a quantidade de finos (partículas menores que 0,037 mm, no produto desagregado, sendo que tal quantidade foi relacionada com o grau de enchimento e com o tempo de residência da polpa através do modelo proposto. O modelo desenvolvido foi validado através da comparação entre os valores obtidos em ensaios de escrubagem, em uma unidade-piloto, e aqueles previstos pelo modelo. Os valores da quantidade de finos, no produto desagregado, previstos pelo modelo apresentaram uma excelente aproximação com os dados experimentais da operação em escala-piloto, visto que a maioria dos valores ficou dentro de uma faixa de ±10% desvio.The aim of this study was to model the bauxite scrubbing of bauxite samples from Miltonia 3, a Vale operation at Pará state, Brazil. The experimental program included the design of a standard laboratory test, from which parameters were derived for predicting the operation of a scrubber in steady state conditions. The amount of fines was determined through screening both feed and product of the scrubbing test. The former was considered as a material characteristic, while the second was the dependent variable, i.e. the result of the scrubbing process. An empirical model was developed according to which the load fraction was found to be the most important variable for the scrubbing process. Residence time was also included in the model due to its importance in designing scrubbers for industrial plants. To validate the model, a

  19. 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

  20. Modeling the water scrubbing process and energy requirements for CO2 capture to upgrade biogas to biomethane

    OpenAIRE

    Nock, William James; Walker, Mark; Kapoor, Rimika; Heaven, Sonia

    2014-01-01

    Water scrubbing is the most widely used technology for removing CO2 from biogas and landfill gas. This work developed a rate-based mass transfer model of the CO2–water system for upgrading biogas in a packed bed absorption column. The simulated results showed good agreement with both a pilot-scale plant operating at 10 bar, and a large-scale biogas upgrading plant operating at atmospheric pressure. The calculated energy requirement for the absorption column to upgrade biogas to 98% CH4 (0.23 ...

  1. Diagnosis of Scrub Typhus

    OpenAIRE

    Koh, Gavin C. K. W.; Maude, Richard J; Paris, Daniel H.; Newton, Paul N.; Blacksell, Stuart D.

    2010-01-01

    Scrub typhus is transmitted by trombiculid mites and is endemic to East and Southeast Asia and Northern Australia. The clinical syndrome classically consists of a fever, rash, and eschar, but scrub typhus also commonly presents as an undifferentiated fever that requires laboratory confirmation of the diagnosis, usually by indirect fluorescent antibody (IFA) assay. We discuss the limitations of IFA, debate the value of other methods based on antigen detection and nucleic acid amplification, an...

  2. Important engineering issues in FCC regenerable wet flue gas scrubbing process%催化裂化可再生湿法烟气脱硫工艺应关注的工程问题

    Institute of Scientific and Technical Information of China (English)

    胡敏; 郭宏昶; 胡永龙; 汤红年; 王刻文; 谭忻; 朱雷鸣

    2012-01-01

    The two typical and industrialized FCC regenerable wet flue gas scrubbing processes I. E. LABSORB process of DuPont BELCO and CANSOLV process of Shell Global Solutions are introduced and the main technical indexes and technical features of the two processes are compared. The main characteristics of RASO process and associated engineering technologies developed by SINOPEC Luoyang Petrochemical Engineering Corporation are described, and the ion liquid recycle flue gas scrubbing process developed by Chengdu Huaxi Chemical Technology Co, Ltd. Are discussed. The impacts of application of regenerable wet flue gas scrubbing process in FCC units on the upstream flue gas expander, waste heat boiler or CO boiler and on operating parameters and capacity of the downstream sulfur recovery unit are studied in detail. It is pointed out that the absorbent ( scrubbing liquid) is the core technology of the regenerable wet flue gas scrubbing process, which determines the advance of the technology as well as capital investment and energy consumption of the flue gas scrubbing unit. The engineering technologies for application of regenerable wet flue gas scrubbing technology in FCC unit need to be further improved in respect of long-term operation, equipment layout & plot area requirement, capital vestment, energy consumption and operating costs, etc. When selecting the regenerable wet flue gas scrubbing for FCC unit, the impacts on upstream flue gas expander, waste heat boiler or CO boiler and the downstream sulfur recovery unit have to be considered to design FCC unit, flue gas scrubbing unit and sulfur recovery unit into an integrated complex.The two typical and industrialized FCC regenerable wet flue gas scrubbing processes I. E. LABSORB. Process of DuPont, BELCO, And CANSOLV, Process of Shell Global Solutions are introduced and the main technical indexes and technical features of the two processes are compared. The main characteristics of RASO process and associated engineering

  3. 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

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

    Science.gov (United States)

    Limoli, Alice; Langone, Michela; Andreottola, Gianni

    2016-07-01

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

  5. 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

    Carbon dioxide capture using aqueous ammonia is a post-combustion technology that has shown a good potential. Therefore this process is studied by measuring the rate of absorption of carbon dioxide by aqueous ammonia and by performing process simulation. The rate of absorption of carbon dioxide by...... 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...

  6. Scrub typhus during pregnancy

    Directory of Open Access Journals (Sweden)

    Vaddadi S

    2016-04-01

    Full Text Available Scrub typhus is an uncommon cause of acute febrile illness during pregnancy. If not diagnosed early and treated appropriately it can lead to adverse maternal and foetal outcome. We report the case of a 27-year-old woman, gravida 2, para 1, live birth 1, with 29 weeks gestation who presented to the hospital with high grade fever, chills, severe headache and body pains of 9 days duration. The diagnosis of scrub typhus was confirmed by serum immunochromatography. She was successfully treated with azithromycin, and discharged. There were no foetal complicatons.

  7. Pancreatitis in scrub typhus

    Directory of Open Access Journals (Sweden)

    Alok Bhatt

    2014-01-01

    Full Text Available Scrub typhus is a rickettsial infection prevalent in most parts of India. Acute pancreatitis with pseudocyst formation is a rare complication of this condition. This paper reports acute renal failure, pancreatitis and pseudocyst formation in a 48-year-old female with scrub typhus. Ultrasonography of the abdomen revealed a bulky pancreas with fluid seen along the body of the pancreas in the lesser sac. The infection was successfully treated with doxycycline and supportive treatment. Pancreatitis was managed conservatively. This case report highlights the importance of identifying and managing uncommon complications of a common tropical disease for optimum outcome.

  8. PEDIATRIC SCRUB TYPHUS WITH MENINGOENCEPHALITIS

    OpenAIRE

    Swati M; Deepika,

    2014-01-01

    BACKGROUND: Pediatric Scrub typhus is under-diagnosed but life threatening febrile illness which requires early treatment. CASE CHARACTERISTICS: A 2-year-old boy presenting with fever, maculopapular rash, hepatosplenomegaly, altered sensorium and hemiparesis. OUTCOME: He was diagnosed as Scrub Typhus with Meningoencephalitis. MESSAGE: Pediatricians should consider scrub typhus in children with hemorrhagic rash, fever and hepatosplenomegaly, even in the absence of eschar.

  9. A process-based model of ammonia emissions from dairy cows: improved temporal and spatial resolution

    Science.gov (United States)

    Pinder, Robert W.; Pekney, Natalie J.; Davidson, Cliff I.; Adams, Peter J.

    This research has developed an integrated model of a dairy farm that predicts monthly ammonia emission factors based on farming practices and climate conditions, including temperature, wind speed, and precipitation. The model can be used to predict the seasonal and geographic variations in ammonia emission factors, which are important for accurately predicting aerosol nitrate concentrations. The model tracks the volume of manure and mass of ammoniacal nitrogen as the manure moves through the housing, storage, application, and grazing stages of a dairy farm. Most of the processes of ammonia volatilization are modeled explicitly, but poorly understood processes are parameterized and tuned to match empirical data. The tuned model has been compared to independent experimental data and is shown to be robust over the range of experimental conditions. We have characterized the differences in emissions resulting from changes in climate conditions and farming practices and found that both of these factors are significant and should be included when developing a national inventory.

  10. Large scale database scrubbing using object oriented software components.

    OpenAIRE

    Herting, R. L.; Barnes, M. R.

    1998-01-01

    Now that case managers, quality improvement teams, and researchers use medical databases extensively, the ability to share and disseminate such databases while maintaining patient confidentiality is paramount. A process called scrubbing addresses this problem by removing personally identifying information while keeping the integrity of the medical information intact. Scrubbing entire databases, containing multiple tables, requires that the implicit relationships between data elements in diffe...

  11. 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

  12. 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.

  13. 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...

  14. 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

  15. Duodenal perforation precipitated by scrub typhus

    Directory of Open Access Journals (Sweden)

    Raghunath Rajat

    2015-01-01

    Full Text Available Scrub typhus is an acute febrile illness usually presenting with fever, myalgia, headache, and a pathognomonic eschar. Severe infection may lead to multiple organ failure and death. Gastrointestinal tract involvement in the form of gastric mucosal erosions and ulcerations owing to vasculitis resulting in gastrointestinal bleeding is common. This process may worsen a pre-existent asymptomatic peptic ulcer, causing duodenal perforation, and present as an acute abdomen requiring surgical exploration. We report the case of a patient with no previous symptoms or risk factors for a duodenal ulcer, who presented with an acute duodenal perforation, probably precipitated by scrub typhus infection.

  16. Duodenal Perforation Precipitated by Scrub Typhus.

    Science.gov (United States)

    Rajat, Raghunath; Deepu, David; Jonathan, Arul Jeevan; Prabhakar, Abhilash Kundavaram Paul

    2015-01-01

    Scrub typhus is an acute febrile illness usually presenting with fever, myalgia, headache, and a pathognomonic eschar. Severe infection may lead to multiple organ failure and death. Gastrointestinal tract involvement in the form of gastric mucosal erosions and ulcerations owing to vasculitis resulting in gastrointestinal bleeding is common. This process may worsen a pre-existent asymptomatic peptic ulcer, causing duodenal perforation, and present as an acute abdomen requiring surgical exploration. We report the case of a patient with no previous symptoms or risk factors for a duodenal ulcer, who presented with an acute duodenal perforation, probably precipitated by scrub typhus infection. PMID:26069430

  17. Development of a novel method to recover rare earths from H2SO4 scrub solution obtained in DNPPA-TOPO-MGA process

    International Nuclear Information System (INIS)

    Appreciable concentration of rare earths (∼ 1.0 g/L) particularly heavy rare earths in wet process phosphoric acid (WPA) have drawn considerable interest in recovering them as a by-product while processing WPA for uranium recovery. WPA is often concentrated to merchant grade phosphoric acid (MGA) for trading purposes. Recently a novel process based on the use of synergistic mixture of 0.6M DNPPA (di-nonyl phenyl phosphoric acid) and 0.3 M TOPO (tri-n-octyl phosphine oxide) has been reported to recover uranium from MGA. An effort for simultaneous recovering of rare earths in the same process would not only improve the economics of the process but will lead to conserve the natural resources and also make the acid more environmental friendly. In the present work a novel method for the precipitation of employing a mixture of sulfamic acid and sodium nitrite for the recovery of rare earths as double sulphate from sulphuric acid scrub solution has been developed

  18. Ammonia, nitrite and nitrate nitrogen removal from polluted source water with ozonation and BAC processes

    International Nuclear Information System (INIS)

    Studies on the removal of ammonia-, nitrite-, and nitrate nitrogen with ozonation (O3), sand filtration (SF), biological activated carbon (BAC), SF-BAC, and/or O3-BAC processes were carried out in two pilot plants and a full scale plant, respectively. The results showed that all of the tested processes exhibited certain nitrogen removal efficiencies, of which both the O3-SF-BAC and O3-BAC processes were most effective and efficient in removing ammonia nitrogen, with mean removal efficiencies of some 90 and 80 percent, respectively. Ozonation was found able to oxidize some organic nitrogen into ammonia, and nitrite ion into nitrate ion. It was also found out, with interest, that the O3-BAC process can carry the nitrification process to the end under sufficient DO content, as well as more hydrocarbon substrates through ozonation that are more easily assimilated by some strains of nitrobacter that can multiply heterotrophically in its carbon beds. In the BAC process, both the DO and easily assimilated substrate contents were too low in its carbon beds due to no ozonation to sustain nitrobacter growth; but the nitrite conversion bacteria, like nitrosomas, can survive under such conditions. As a result, nitrite or nitrate ion content increased multiply in the effluents from BAC or O3-BAC processes over their influents, respectively. The removal mechanisms of various processes for the three forms of nitrogen were studied and discussed, and the optimum design parameters were determined as well

  19. Sulfur dioxide scrubbing system

    Energy Technology Data Exchange (ETDEWEB)

    Dahlstrom, D.A.; Cornell, C.F.

    1976-11-02

    Sulfur dioxide is scrubbed from stack gases in an absorption device by a sodium-based aqueous scrubbing solution, a portion of which is subsequently and continuously regenerated outside the absorption apparatus by a causticizing reaction with slaked lime. The causticized solution is routed through a settling device wherefrom a portion of the aqueous sediment is returned to the causticizing zone to provide seed crystals which encourage the formation of larger sized solid particles; also, a portion of the aqueous sediment from the settling device is continuously mechanically dewatered and then removed from the system. The liquid effluent solution from the settling device is passed to a solids-contacting and reaction device for mixing with sodium carbonate in order to reduce the calcium ion concentration and the solids content of the solution. The underflow of the solids-contacting device is conveyed back to the causticizing zone and the clarified overflow, i.e., the regenerated scrubbing liquor, is conveyed to the absorption apparatus.

  20. Integration of a gas turbine with an ammonia process for improving energy efficiency

    International Nuclear Information System (INIS)

    This paper is intended to investigate how one can improve the overall energy efficiency of an ammonia process. A gas turbine is integrated with the process to reduce the exergy loss associated with ammonia synthesis loop and produce electricity. Combined Pinch and Exergy Analysis is applied to identify how exergy loss is distributed throughout heat transfer process. This is needed to find appropriate placement for gas turbine integration. Having introduced an exergy loss index for the whole plant, including the heat transfer process and gas turbine system, optimum shaftwork can be generated through recovering part of the exergy loss. Eventually, heat integration of the process streams is done to reduce additional consumption of high pressure steam caused by temperature drop in gas turbine. The results show that 4 MW of electricity can be produced in exchange of adding 7350 kW of high pressure steam. Total amount of exergy loss is reduced by 3323 kW, which indicates 19% reduction compared to the existing process. Based on the economic data, the net income is estimated to be 2,549,653 US$/y with 3 years payback. -- Highlights: • A new configuration is proposed to improve the energy efficiency of ammonia plant. • Combined pinch and exergy is used to obtain the new configuration conditions. • Considerable net income is achieved by proposed modifications

  1. PEDIATRIC SCRUB TYPHUS WITH MENINGOENCEPHALITIS

    Directory of Open Access Journals (Sweden)

    Swati M

    2014-11-01

    Full Text Available BACKGROUND: Pediatric Scrub typhus is under-diagnosed but life threatening febrile illness which requires early treatment. CASE CHARACTERISTICS: A 2-year-old boy presenting with fever, maculopapular rash, hepatosplenomegaly, altered sensorium and hemiparesis. OUTCOME: He was diagnosed as Scrub Typhus with Meningoencephalitis. MESSAGE: Pediatricians should consider scrub typhus in children with hemorrhagic rash, fever and hepatosplenomegaly, even in the absence of eschar.

  2. Scrub Typhus, Republic of Palau

    OpenAIRE

    Demma, Linda J.; McQuiston, Jennifer H.; Nicholson, William L.; Murphy, Staci M.; Marumoto, Pearl; Sengebau-Kingzio, J. Maireng; Kuartei, Stevenson; Durand, A. Mark; Swerdlow, David L.

    2006-01-01

    Scrub typhus, caused by Orientia tsutsugamushi, is a severe febrile illness transmitted to humans by trombiculid mites, which normally feed on rodents. The first known outbreak of scrub typhus in Palau occurred in 2001 to 2003 among residents of the remote southwest islands. To determine the extent of scrub typhus distribution in Palau, we tested serum samples from humans and rodents for antibodies to O. tsutsugamushi. Of 212 Palau residents surveyed in 2003, 101 (47.6%) had immunoglobulin G ...

  3. 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

  4. 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

    The use of aqueous ammonia is a promising option to capture carbon dioxide from power plants thanks to the potential low heat requirement during the carbon dioxide desorption compared to monoethanolamine (MEA) based process. The patented Chilled Ammonia Process developed by Alstom absorbs carbon...... 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 a...... same range as the values reported recently for advanced amine processes. Assuming that cold cooling water is available, the electricity consumption remains limited. Hence the Chilled Ammonia Process is a promising option for post combustion carbon dioxide capture....

  5. A New Process for Co-production of Ammonia and Methanol

    International Nuclear Information System (INIS)

    A new process for co-production of ammonia and methanol is proposed. The process involves the production of synthesis gas by oxygen blown auto thermal reformer (ATR) at a pressure of 40-100 bars, a methanol synthesis loop at a pressure of 50-100 bars and an ammonia synthesis loop at a pressure of 200-300 bars. The oxygen required for the ATR is supplied by an air separation plant. The synthesis gases from the ATR are cooled and compressed, in a first stage compression, to the required methanol loop pressure. The purge stream from the methanol loop is sent to an intermediate temperature shift converter ITSC followed by a physical solvent CO2 removal unit and them purified in a pressure Swing Adsorber (PSA). The purified hydrogen from the PSA together with the almost pure nitrogen from the air separation plant are re compressed, in a second stage compression

  6. 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.

  7. Research and practice of intelligent scrub dispensing system in operation room under process reengineering%基于流程再造的手术室智能更衣系统的研究与实践

    Institute of Scientific and Technical Information of China (English)

    凌蒙蒙; 张群瑜; 潘传迪

    2016-01-01

    目的:采用信息技术优化手术室更衣流程,改善手工流程的不足。方法:集成自助更衣机、CPU卡、电子储物柜、红外感应器等设备,开发手术室智能更衣软、硬件系统。结果:完成手术室智能更衣系统研发并投入正常运行,实现手术人员签到和签退、自动出衣、自动分配及回收储物柜、回收手术衣等功能。结论:手术室智能更衣系统对优化手术室更衣流程,缩短医务人员术前更衣时间,改善手术室环境,节约人力成本,提高服务效率具有积极的作用。%Objective: To optimize scrub dispensing process in operating room and replace previous manual process by information technology. Methods: Integrate self-service scrub dispensing machine, CPU card, electronic lockers, infrared sensors and other equipment were used to develop intelligent scrub dispensing hardware and software system in operation room. Results: The system is developed and put into normal operation. The intelligent scrub dispensing system achieves automatic operation personnel sign-in and sign-out, self serving surgical gowns, automatic allocation and locker reuse, self-recycle of dirty surgical gowns and other functions. Conclusions: The intelligent scrub dispensing system in operation room is a positive effect on optimizing the scrub dispensing process in operating room, shorting the time of medical personnel to change surgical gowns, improving the environment of the operation room, reducing labor costs, improving the service efficiency.

  8. SPS: scrubbing or coating ?

    CERN Document Server

    Jimenez, J M

    2012-01-01

    The operation of the SPS with high intensity bunched beams is limited by the electron cloud building-up in both the arcs and long straight sections. Two consolidation options have been considered: mitigation of the electron cloud using coatings or relying, as before, on the scrubbing runs. A status report on both options will be given with a particular emphasis on measurements plans for 2012 and pending issues. The testing needs, corresponding beam parameters and MD time in 2012 will be addressed. The criteria for the decision making and the corresponding schedule will be discussed.

  9. A low energy aqueous ammonia CO2 capture process

    DEFF Research Database (Denmark)

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

    2014-01-01

    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...... 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 based CO2 capture with a thermal decomposition reactor. The overall energy penalty is reduced at the expense of introducing a solid handling section which consists of a saturation reactor, a crystallizer and a belt filter. The feasibility of the present approach is demonstrated by...

  10. NOx retention in scrubbing column

    International Nuclear Information System (INIS)

    During the UO2 dissolution in nitric acid, some different species of NOx are released. The off gas can either be refluxed to the dissolver or be released and retained on special columns. The final composition of the solution is the main parameter to take in account. A process for nitrous gases retention using scubber columns containing H2O or diluted HNO3 is presented. Chemiluminescence measurement was employed to NOx evalution before and after scrubbing. Gas flow, temperature, residence time are the main parameters considered in this paper. For the dissolution of 100g UO2 in 8M nitric acid, a 6NL/h O2 flow was the best condition for the NO/NO2 oxidation with maximum adsorption in the scrubber columns. (author)

  11. Review and Preliminary Evaluation of Pool Scrubbing Models

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Hyun-Joung; Ha, Kwang Soon; An, Sang Mo; Kim, Hwan Yeol [KAERI, Daejeon (Korea, Republic of); Jang, Dong Soon [Chungnam National University, Daejeon (Korea, Republic of)

    2015-05-15

    If a severe accident occurs in a nuclear power plant (NPP), the aerosol and gaseous fission products might be produced in the reactor vessel and the reactor cavity during a core meltdown and molten corium-concrete interaction (MCCI) process, and then released to the environment after the containment failure. FCVS (Filtered Containment Venting System) is one of the equipment for retaining the containment integrity by discharging the high-temperature and high-pressure fission products to the environment after passing through the filtration system. In general, the FCVS is categorized into two types, wet and dry types. The scrubbing pool could play an important role in the wet type FCVS because a large amount of aerosol is captured in the water pool. The pool scrubbing phenomena have been modelled and embedded in several computer codes, such as SPARC (Suppression Pool Aerosol Removal Code), BUSCA (BUbble Scrubbing Algorithm) and SUPRA (Suppression Pool Retention Analysis). These codes aim at simulating the pool scrubbing process and estimating the decontamination factor (DF) in the water pool, which is defined as the ratio of initial specific radioactivity to final specific radioactivity after passing through the water pool. In the present paper, the pool scrubbing models in the SPARC and BUSCA codes were reviewed and the pool scrubbing parameters such as globule diameter and bubble diameter were evaluated preliminarily. To estimate the decontamination factor (DF) of radioactive aerosol in the water pool during the severe accident in a nuclear power plant, variety models and codes has been developed. The pool scrubbing models such as hydrodynamics, thermo-hydraulics, and aerosol removal models in the SPARC and BUSCA codes were reviewed. Bubble diameter in the swarm region directly influence on decontaminant factor. Some pool scrubbing parameters such as globule diameter and bubble diameter were evaluated preliminarily. The decontamination factor by current pool

  12. Clear Liquor Scrubbing with Anhydrite Production

    International Nuclear Information System (INIS)

    The objective of this project to develop an advanced flue gas desulfurization (FGD) process that has decreased capital and operating costs, higher SO2 removal efficiency, and better by-product solids quality than existing, commercially available technology. A clear liquor process (which uses a scrubbing liquid with no solids) will be used to accomplish this objective rather than a slurry liquor process (which contains solids). This clear liquor scrubbing (CLS) project is focused on three research areas: (1) Development of a clear liquor scrubbing process that uses a clear solution to remove SO2 from flue gas and can be operated under inhibited-oxidation conditions; (2) Development of an anhydrite process that converts precipitated calcium sulfite to anhydrous calcium sulfate (anhydrite); and (3) Development of an alkali/humidification process to remove HCl from flue gas upstream of the FGD system. The anhydrite process also can be retrofit into existing FGD systems to produce a valuable by-product as an alternative to gypsum. This fits well into another of FETC's PRDA objectives of developing an advanced byproduct recovery subsystem capable of transforming SO2 into a useable byproduct or high-volume valuable commodities of interest. This paper describes the proposed processes, outlines the test approach, and preliminary Phase I test results

  13. 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.

  14. 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.

  15. Power requirements of biogas upgrading by water scrubbing and biomethane compression: comparative analysis of various plant configurations

    OpenAIRE

    Budzianowski, Wojciech; Wylock, Christophe; Marciniak, Przemysław

    2016-01-01

    Biogas upgrading by water scrubbing followed by biomethane compression is an environmentally benign process. It may be achieved using various plant configurations characterised by various power requirements with associated effects on biomethane sustainability. Therefore, the current study has been undertaken to systematically investigate the power requirements of a range of water scrubbing options. Two groups of water scrubbing are analysed: (1) high pressure water scrubbing (HPWS) and (2) ne...

  16. 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...... investigate the performance of the ISEC system. The ISEC concept approaches the efficiency of a number of heat pumps in series and the COP of the system may reach 6.8, which is up to 25 % higher than a conventional heat pump heating water in one step....

  17. Shrub-Scrub Habitat Evaluation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Conversion of the current shrub-scrub habitats west of Sandpiper Road and north of the Back BayNational Wildlife Refuge, into recreational facilities for a new...

  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. 几种催化裂化装置湿法烟气脱硫技术浅析%Analysis of FCCU wet flue gas scrubbing technologies

    Institute of Scientific and Technical Information of China (English)

    汤红年

    2012-01-01

    简要介绍催化裂化装置烟气脱硫技术.抛弃法重点介绍了杜邦-贝尔格(DuPont-Belco)公司的EDV技术、埃克森美孚( Exxon Mobil)的WGS技术和氨法烟气脱硫技术;可再生循环吸收法简要介绍中国石化集团洛阳石油化工工程公司自行开发的RASOC可再生湿法烟气脱硫工艺及其具有自主知识产权的LAS吸收剂.对主要湿法烟气脱硫工艺进行了分析,对湿法烟气脱硫工艺中的碱洗法和氨法以及RASOC进行了技术和经济对比.还将RASOC工艺与国内催化裂化烟气脱硫领域仅有的已应用技术(EDV)进行了对比分析,表明RASOC技术和EDV技术烟气中SO2质量浓度临界点均为6.278 g,/m3,当烟气中SO2浓度低于临界点时,采用EDV技术经济上更合理;当烟气中SO2浓度高于临界点时,采用RASOC技术经济上更合理.%The FCCU flue gas scrubbing technologies are briefed. The abandoning technologies are described in detail, such as DuPont-Belco' s EDV process, Exxon Mobil' s WGS process and ammonia scrubbing process. In addition, the regenerable recycle absorption process-RASOC and proprietary LAS absorbent developed by Sinopec Luoyang Petrochemical Engineering Corporation are introduced. The main wet flue gas scrubbing processes are analyzed, and technology and economics are compared for alkaline scrubbing process, ammonia process and RASOC process. The comparison analysis of RASOC process and EDV process applied in the flue gas scrubbing of FCC units in China shows that the critical concentration of S02 in flue gas is 6. 278 g/m3 for RASOC and EDV processes. When the SO2 in flue gas is lower than the critical value, the application of EDV process is more economic; When the SO2 in flue gas is higher than the critical value, the selection of RASOC process is more economically feasible.

  20. 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 is...... 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...

  1. 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.

  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. Synthesis and photocatalytic performances of BiVO4 by ammonia co-precipitation process

    International Nuclear Information System (INIS)

    This paper reports the preparation and photocatalytic performance of Bismuth vanadate (BiVO4) by a facile and inexpensive approach. An amorphous BiVO4 was first prepared by a co-precipitation process from aqueous solutions of Bi(NO3)3 and NH4VO3 using ammonia. Followed by heating treatment at various temperatures, the amorphous phase converted to crystalline BiVO4 with a structure between monoclinic and tetragonal scheelite. The crystallization of BiVO4 occurred at about 523 K, while the nanocrystalline BiVO4 were formed with a heat-treatment of lower than 673 K. However, when the heat-treatment was carried out at 773 K, the accumulation of nanocrystals to bulk particles was observed. The photocatalytic performances of the materials were investigated by O2 evolution under visible-light, and MB decomposition under solar simulator. The results demonstrated that the crystalline structure is still the vital factor for the activities of both reactions. However, the crystallinity of BiVO4 gives a major influence on the activity of O2 evolution, whereas the surface area, plays an important role for photocatalytic MB decomposition. - Abstract: BiVO4 was prepared by a co-precipitation process using aqueous ammonia solution, followed by heating treatment at various temperatures. The crystalline structure and crystallization process, and their influences on photocatalytic O2 evolution and organic pollutants degradation were investigated. It demonstrated that the crystalline structure is still the vital factor for the activities of both reactions. However, the crystallinity of BiVO4 gives a major influence on the activity of O2 evolution, whereas the surface area, plays an important role for photocatalytic MB decomposition. Display Omitted

  4. 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.

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

    Science.gov (United States)

    Pospíšil, Jiří; Fortelný, Zdeněk

    2012-04-01

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

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

    Science.gov (United States)

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

    1983-06-01

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

  8. Scrub Typhus with Unusual Presentation

    Directory of Open Access Journals (Sweden)

    A.S. Praveen Kumar

    2014-01-01

    Full Text Available Scrub typhus is an acute, febrile zoonosis caused by an obligate intracellular bacterium Orientia tsutsugamushi. The clinical manifestations of the disease range from subclinical to fatal organ failure. The common symptoms are fever, chills, headache, myalgia, dry cough, lymphadenopathy, and gastrointestinal disturbances. The presentation with complications is usually due to delay in diagnosis and treatment. We report three cases of scrub typhus that presented with features of meningo-encephalitis, which is very unusual, and all patients recovered with empirical doxycycline treatment.

  9. One hospital's clinical evaluation of brushless scrubbing.

    Science.gov (United States)

    Berman, Mara

    2004-02-01

    BRUSHLESS SCRUBBING rapidly is becoming an accepted method for surgical hand scrubbing. AN EVALUATION was undertaken at an acute care hospital in the southeastern United States to examine brushless scrubbing before laminectomy, craniotomy, and colectomy procedures. PATIENTS DID NOT SHOW an increase in postoperative surgical site infections when the brushless scrubbing product was used. SATISFACTION AND COMPLIANCE among users of the product was positive. PMID:15002831

  10. Acute Cholecystitis in Patients with Scrub Typhus

    OpenAIRE

    Lee, Hyun; Ji, Misuk; Hwang, Jeong-Hwan; Lee, Ja-Yeon; Lee, Ju-Hyung; Chung, Kyung Min; Lee, Chang-Seop

    2015-01-01

    Acute cholecystitis is a rare complication of scrub typhus. Although a few such cases have been reported in patients with scrub typhus, the clinical course is not well described. Of 12 patients, acute cholecystitis developed in 66.7% (8/12) of patients older than 60 yr. The scrub typhus group with acute cholecystitis had marginal significant longer hospital stay and higher cost than the group without cholecystitis according to propensity score matching. Scrub typhus should be kept in mind as ...

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

    Science.gov (United States)

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

  12. Scrub typhus, Republic of Palau.

    Science.gov (United States)

    Demma, Linda J; McQuiston, Jennifer H; Nicholson, William L; Murphy, Staci M; Marumoto, Pearl; Sengebau-Kingzio, Maireng; Kuartei, Stevenson; Durand, A Mark; Swerdlow, David L

    2006-02-01

    Scrub typhus, caused by Orientia tsutsugamushi, is a severe febrile illness transmitted to humans by trombiculid mites, which normally feed on rodents. The first known outbreak of scrub typhus in Palau occurred in 2001 to 2003 among residents of the remote southwest islands. To determine the extent of scrub typhus distribution in Palau, we tested serum samples from humans and rodents for antibodies to O. tsutsugamushi. Of 212 Palau residents surveyed in 2003, 101 (47.6%) had immunoglobulin G (IgG) antibody titers >1:64, and 56 (26.4%) had concurrent IgG and IgM antibody titers >1:512 and 1:64, respectively. Of 635 banked serum samples collected from Palau residents in 1995, 34 (5.4%) had IgG antibody titers >1:64. Sera collected from rodents (Rattus norvegicus and R. rattus) in 2003 and 2005 were tested, and 18 (28.6%) of 63 had IgG antibody titers >1:64. These findings suggest that scrub typhus is endemic in Palau. PMID:16494757

  13. Acute Cholecystitis in Patients with Scrub Typhus.

    Science.gov (United States)

    Lee, Hyun; Ji, Misuk; Hwang, Jeong-Hwan; Lee, Ja-Yeon; Lee, Ju-Hyung; Chung, Kyung Min; Lee, Chang-Seop

    2015-11-01

    Acute cholecystitis is a rare complication of scrub typhus. Although a few such cases have been reported in patients with scrub typhus, the clinical course is not well described. Of 12 patients, acute cholecystitis developed in 66.7% (8/12) of patients older than 60 yr. The scrub typhus group with acute cholecystitis had marginal significant longer hospital stay and higher cost than the group without cholecystitis according to propensity score matching. Scrub typhus should be kept in mind as a rare etiology of acute cholecystitis in endemic areas because the typical signs of scrub typhus such as skin rash and eschar can present after the abdominal pain. PMID:26539017

  14. Evaluation of ionic liquids as absorbents for ammonia absorption refrigeration cycles using COSMO-based process simulations

    International Nuclear Information System (INIS)

    Highlights: • NH3–IL absorption cycles are modeled by COSMO-based Aspen simulations. • Proposed a priori computational approach is validated using experimental data. • Cycle performance was analyzed for conventional and task-specific ILs. • IL solvents with high NH3 absorption capacity improve the cycle performance. • Using IL mixtures is revealed as promising alternative in NH3 absorption applications. - Abstract: COSMO-based process simulations with Aspen Plus/Aspen HYSYS are used, for the first time, to a priori estimate the thermodynamic performance of ammonia absorption refrigeration cycles using ionic liquids as absorbents. This allows not only broadening the criteria set used to select/design ionic liquids with optimized properties to be used in that role, but also evaluating innovative strategies to improve the cycle’s performances. COSMO-RS method provides the information required for both creating the ionic liquid non-database components and specifying the COSMOSAC property model to perform Aspen Plus calculations. The computational procedure used here gives at the same time reasonable good property predictions of the vapor (refrigerant) and the condensed (ammonia + ionic liquid) phases as well as physically consistent estimations of the cycle’s performance under different conditions. Current results agree with those previously reported in the literature for several ionic liquid-based systems taken for comparison. In addition, task-specific ionic liquids, with improved properties for ammonia absorption, and also binary ionic liquid mixtures are considered in the analysis. It is obtained that ionic liquids showing higher ammonia absorption capacity among the considered absorbents simultaneously provide the best cycle’s performances. The cycle performances vary in relatively wide intervals depending on the ammonia concentration in the (refrigerant + absorbent) solutions. This behavior is strongly modulated by the ammonia absorption

  15. The bacterial contamination of surgical scrubs.

    Science.gov (United States)

    Krueger, Chad A; Murray, Clinton K; Mende, Katrin; Guymon, Charles H; Gerlinger, Tad L

    2012-05-01

    To our knowledge, no study has examined the bacterial profile of residents' scrubs. The goal of this investigation was to determine the bacterial profile of worn and unworn resident scrubs. Thirty pairs of scrubs were swabbed in 10 predetermined locations both prior to and after being worn continuously by the on-call resident. All swabs were screened for aerobic gram-positive and gram-negative bacteria. Bacteria underwent antimicrobial resistance testing and genetic relatedness by pulsed-field gel electrophoresis. Forty-one percent (123) of unworn scrub samples yielded bacteria, compared with 89% (268) of post-call scrub samples. On unworn scrubs, the most common organisms were coagulase-negative Staphylococcus (CNS; 94), gram positive rods (GPR; 34) and Streptococcus viridians (8). On post-call scrubs, the most common bacteria were CNS (271), micrococcus (51), Staphylococcus aureus (33), and GPR (28). All S. aureus were methicillin susceptible. There were different species, pulse-field types and antibiotic resistance profiles found amongst the CNS identified. No scrubs were found to harbor multidrug-resistant (MDR) organisms. This study found that unworn scrubs harbored normal skin flora and scrubs worn for at least 24 hours have a higher burden of bacteria than unworn scrubs but not an increased incidence of contamination with MDR organisms. PMID:22715444

  16. 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

  17. 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

  18. 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

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. Acute encephalitis syndrome following scrub typhus infection

    OpenAIRE

    Ayan Kar; Dhanaraj, M.; Devaprasad Dedeepiya; Harikrishna, K.

    2014-01-01

    Objective: The aim was to find the incidence of acute encephalitis syndrome (AES) secondary to scrub infection and to observe the clinical, biochemical, radiological profile, and outcomes in these patients. Materials and Methods: A total of 20 consecutive patients of AES were evaluated for scrub infection using scrub typhus immunoglobulin M enzyme linked immuno-sorbant assay positivity along with the presence or absence of an eschar. Clinical profile, routine laboratory tests, cerebrospinal f...

  4. 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

  5. Scrub Typhus Presenting as Acute Mastoiditis

    Directory of Open Access Journals (Sweden)

    Bhushal Lal

    2014-02-01

    Full Text Available Scrub typhus, a zoonosis, is known to present with varied clinical presentation. We present a case of acute mastoiditis who did not respond to conventional antibiotic therapy. The detailed repeat clinical examination revealed lymphadenopathy with eschar and IgM antibodies for scrub typhus by ELISA were positive. Patient had dramatic response to doxycycline therapy.

  6. Scrub Typhus Presenting as Acute Mastoiditis

    OpenAIRE

    Bhushal Lal; Ravinder Singh Minhas; Dev Raj Sharma; Suresh Kumar

    2014-01-01

    Scrub typhus, a zoonosis, is known to present with varied clinical presentation. We present a case of acute mastoiditis who did not respond to conventional antibiotic therapy. The detailed repeat clinical examination revealed lymphadenopathy with eschar and IgM antibodies for scrub typhus by ELISA were positive. Patient had dramatic response to doxycycline therapy.

  7. Scrub typhus: Clinical spectrum and outcome

    Directory of Open Access Journals (Sweden)

    Pradeep M Venkategowda

    2015-01-01

    Full Text Available Background: Scrub typhus is one of the differential diagnoses for fever with thrombocytopenia. ARDS associated with Scrub typhus has high morbidity and mortality. Aims: To evaluate clinical features, lab values, and outcome in patients with scrub typhus and comparison in patients with or without ARDS. Methods: A prospective observational study was conducted on 109 patients with febrile illness and thrombocytopenia during a period of 12 months. All 109 patients were tested with both Immune-chromatography test and Weil felix test. Patients having either Immune-chromatography test/Weil felix test positive have been included and considered as scrub typhus positive whereas negative for both Immune-chromatography and Weil felix test were excluded. Clinical features, lab parameters, and outcome were evaluated in all patients with scrub typhus. Statistical analysis used in this study was T-test. Results: Among 58 patients who were included (After exclusion of 51 patients among total of 109 patients 34 patients had no ARDS and 24 patients had ARDS. The clinical feature like dyspnoea, cough, low blood pressure (MAP<65 mmHg, IVC collapsibility (by ultrasound and laboratory parameters like decreased Hemoglobin, Hematocrit, Serum albumin, and increased serum creatinine, serum total bilirubin, SGOT, SGPT, LDH, CPK, and serum lactate were statistically significant (P < 0.0001 in scrub typhus patients group with ARDS. The higher titers of Weil-felix can be correlated with more severe form of disease according to our observation. All 34 Scrub typhus patients without ARDS recovered completely. Among 24 Scrub typhus patients with ARDS, 22 patients recovered, and 2 patients died. Conclusion: Scrub typhus is an important differential diagnosis in a patients having fever with thrombocytopenia. Scrub typhus associated with ARDS has high morbidity and mortality. Early diagnosis and treatment with doxycycline can prevent the occurrence of ARDS

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

    Science.gov (United States)

    Bartłomiej, Wilk; Arabczyk, Walerian

    2015-08-21

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

  9. 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; Angelidaki, Irini

    2009-01-01

    oxidation) diluted with synthetic wastewater. High ammonium removal was achieved, up to 92.1 +/- 4.9% for diluted UASB-post-digested effluent (95 mg COD L-1) and up to 98.5 +/- 0.8% for diluted partially oxidized effluent (121 mg COD L-1). Mass balance clearly showed that an increase in organic loading...... improved ammonium removal at high organic matter concentration. Up to threshold organic load concentration of 142 mg COD L-1 of UASB-post-digested effluent and 242 mg COD L-1 of partially oxidized effluent, no effect of organic loading on ammonia removal was registered (ammonium removal was above 80...

  10. 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)....

  11. Operating experiences of Heavy Water Plant at Talcher using bithermal ammonia-hydrogen exchange process (Paper No. 1.9)

    International Nuclear Information System (INIS)

    A heavy water plant employing bithermal ammonia-hydrogen exchange process was set up at Talcher (India). The energy consumption in the process is lower as compared to monothermal process. The plant performance was affected by various problems and has resulted in low heavy water production. The problems are: (i)formation of solid deposits, (ii)inability of exchange towers to process design gas flow rates, (iii)inadequate exchange efficiency of the sieve trays provided as exchange trays, and (iv)differential amide concentration in different plant sections. These problems and their effect on the overall plant performance are discussed in detail and modifications to improve the performance are suggested. (author). 4 figs

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

    Science.gov (United States)

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

    2014-05-01

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

  13. 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

  14. Investigation of the effect of free ammonia concentration upon leachate treatment by shortcut biological nitrogen removal process.

    Science.gov (United States)

    Chung, Jinwook; Bae, Wookeun; Lee, Yong-Woo; Ko, Gwang-Beom; Lee, Sang-Uk; Park, Seong-Jun

    2004-01-01

    A shortcut biological nitrogen removal (SBNR) process was operated to treat an ammonium rich landfill leachate using a pilot-scale reactor. The SBNR process was intended to oxidize ammonia to nitrite and, then, to reduce it to nitrogen gas. When the hydraulic retention time was 4-3 days, a half of the ammonium oxidized was accumulated as nitrite in the oxidation tank. The nitrite was denitrified completely in the anoxic tank when recycled. The average free ammonia (FA) concentration in the ammonium oxidation tank was 3.7 mg/L. The specific substrate utilization rates of ammonium oxidizers and nitrite oxidizers were investigated at varying FA concentrations through batch experiments. The highest specific ammonium oxidation rate was observed when the FA concentration was 10 mg/L. The rate decreased slightly when the FA concentration was increased to 20 or 50 mg/L, or decreased significantly when it was 5 mg/L. In case of nitrite oxidation, the specific nitrite utilization rate decreased significantly with increasing FA concentration up to 10 mg/L. Consequently, the optimal FA concentration in leachate treatment was 10 mg/L for maximum nitrite accumulation and maximum ammonium removal, or 5 mg/L for lower ammonium concentration and reasonable nitrite accumulation. PMID:15242116

  15. Support for Systematic Code Reviews with the SCRUB Tool

    Science.gov (United States)

    Holzmann, Gerald J.

    2010-01-01

    SCRUB is a code review tool that supports both large, team-based software development efforts (e.g., for mission software) as well as individual tasks. The tool was developed at JPL to support a new, streamlined code review process that combines human-generated review reports with program-generated review reports from a customizable range of state-of-the-art source code analyzers. The leading commercial tools include Codesonar, Coverity, and Klocwork, each of which can achieve a reasonably low rate of false-positives in the warnings that they generate. The time required to analyze code with these tools can vary greatly. In each case, however, the tools produce results that would be difficult to realize with human code inspections alone. There is little overlap in the results produced by the different analyzers, and each analyzer used generally increases the effectiveness of the overall effort. The SCRUB tool allows all reports to be accessed through a single, uniform interface (see figure) that facilitates brows ing code and reports. Improvements over existing software include significant simplification, and leveraging of a range of commercial, static source code analyzers in a single, uniform framework. The tool runs as a small stand-alone application, avoiding the security problems related to tools based on Web browsers. A developer or reviewer, for instance, must have already obtained access rights to a code base before that code can be browsed and reviewed with the SCRUB tool. The tool cannot open any files or folders to which the user does not already have access. This means that the tool does not need to enforce or administer any additional security policies. The analysis results presented through the SCRUB tool s user interface are always computed off-line, given that, especially for larger projects, this computation can take longer than appropriate for interactive tool use. The recommended code review process that is supported by the SCRUB tool consists of

  16. Scrub typhus hepatitis confirmed by immunohistochemical staining

    Institute of Scientific and Technical Information of China (English)

    Jong-Hoon Chung; Sung-Chul Lim; Na-Ra Yun; Sung-Heui Shin; Choon-Mee Kim; Dong-Min Kim

    2012-01-01

    Scrub typhus is an acute febrile disease caused by Orientia tsutsugamushi (O.tsutsugamushi).We report herein the case of a woman who presented with fever and elevated serum levels of liver enzymes and who was definitively diagnosed with scrub typhus by histopathological examination of liver biopsy specimens,serological tests and nested polymerase chain reaction.Immunohistochemical staining using a monoclonal anti-O.tsutsugamushi antibody showed focally scattered positive immunoreactions in the cytoplasm of some hepatocytes.This case suggests that scrub typhus hepatitis causes mild focal inflammation due to direct liver damage without causing piecemeal necrosis or interface hepatitis.Thus,scrub typhus hepatitis differs from acute viral hepatitis secondary to liver damage due to host immune responses,which causes severe Iobular disarray with diffuse hepatocytic degeneration,necrosis and apoptosis as well as findings indicative of hepatic cholestasis,such as hepatic bile plugs or brown pigmentation of hepatocytes.

  17. Scrub typhus mimicking Parkinson’s disease

    OpenAIRE

    Premaratna, Ranjan; Wijayalath, S. H. Nuwan Chamara; Miththinda, J. K. N. Dhanushka; Bandara, N. K. B. K. R. G. Wijesinghe; de Silva, H. Janaka

    2015-01-01

    Background Scrub typhus is a re-emerging infection in Sri Lanka. It often poses a diagnostic challenge and tends to present as a febrile illness of uncertain origin. Undiagnosed illness may progress to serious multi-systemic complications. Here we report a case of scrub typhus presenting with features of Parkinsonism. Case presentation A 62-year-old previously healthy Sri Lankan native male from the Western province of Sri Lanka presented with high fever with malaise, myalgia and arthralgia f...

  18. 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

  19. 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

    Ammonia (NH4+/NH3) inhibition during anaerobic digestion process is one of the most frequent problems existing in biogas plants, resulting in unstable process and reduced biogas production. In this study, we developed a novel hybrid system, consisted of a submersed microbial resource recovery cell...

  20. Efficiency improvements for the coal-fired power plant retrofit with CO2 capture plant using chilled ammonia process

    International Nuclear Information System (INIS)

    Highlights: • NH3 has been proposed as a viable solvent to reduce the efficiency penalty. • Retrofit of a coal-fired power plant with a chilled ammonia process was analysed. • A base case scenario showed that efficiency penalty fell between 10.4% and 10.9%. • Alternative process configurations for the efficiency improvement were investigated. • The efficiency penalty was reduced to 8.7%. - Abstract: Development of clean coal technologies for power generation is crucial in meeting the European Union 2050 target to reduce greenhouse gas emissions. CO2 capture technology using chemical solvents currently has the highest potential to decarbonise coal-based power generation. Substitution of amine solvent with NH3 has been proposed as a viable option to reduce the efficiency penalty. In this study, the scenario of a supercritical coal-fired power plant retrofitted with a chilled ammonia process capture plant and CO2 compression unit was modelled in a common simulation environment. To fully assess the integration impact on power plant performance, the pressure loss due to steam extraction has been taken into account by using the Stodola ellipse law. Analysis of a basic integration scenario revealed that the efficiency penalty fell between 10.4% and 10.9% points depending on the stripper pressure. The quality of extracted steam became insufficient to meet the reboiler heat requirement above a stripper pressure of 21.8 bar, and the lowest efficiency penalty was obtained when reboiler condensate was returned to the deaerator in the power plant. In evaluating measures to improve integration, the efficiency penalty was reduced to 8.7–8.8% points through the integration of a single-stage or two-stage auxiliary steam turbine, respectively, and a back-pressure turbine. Nevertheless, the analysis has indicated that the net impact on power plant performance is similar to that of an amine-based post-combustion CO2 capture plant

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

    International Nuclear Information System (INIS)

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

  2. 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.

  3. Acute encephalitis syndrome following scrub typhus infection

    Directory of Open Access Journals (Sweden)

    Ayan Kar

    2014-01-01

    Full Text Available Objective: The aim was to find the incidence of acute encephalitis syndrome (AES secondary to scrub infection and to observe the clinical, biochemical, radiological profile, and outcomes in these patients. Materials and Methods: A total of 20 consecutive patients of AES were evaluated for scrub infection using scrub typhus immunoglobulin M enzyme linked immuno-sorbant assay positivity along with the presence or absence of an eschar. Clinical profile, routine laboratory tests, cerebrospinal fluid (CSF analysis, and neuroimaging were analyzed. Patients were treated with doxycycline and followed-up. Results: Among 20 consecutive patients with AES, 6 (30% were due to scrub infection. They presented with acute onset fever, altered sensorium, seizures. "Eschar" was seen in 50% of patients. CSF done in two of them was similar to consistent with viral meningitis. Magnetic resonance imaging brain revealed cerebral edema, bright lesions in the putamen and the thalamus on T2-weighted and fluid-attenuated inversion recovery sequences. Renal involvement was seen in all patients. All patients responded well to oral doxycycline. Conclusion: AES is not an uncommon neurological presentation following scrub typhus infection. It should be suspected in all patients with fever, altered sensorium, and renal involvement. Oral doxycycline should be started as early as possible for better outcomes.

  4. 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.

  5. Photocatalytic oxidation of nitric oxide from simulated flue gas by wet scrubbing using ultraviolet/TiO2/H2O2 process

    Institute of Scientific and Technical Information of China (English)

    张波; 仲兆平; 付宗明

    2015-01-01

    Nitric oxide (NO) from flue gas is hard to remove because of low solubility and reactivity. A new technology for photocatalytic oxidation of NO using ultraviolet (UV)/TiO2/H2O2 process is studied in an efficient laboratory-scale reactor. Effects of several key operational parameters on NO removal efficiency are studied, including TiO2 content, H2O2 initial concentration, UV lamp power, NO initial content, oxygen volume fraction and TiO2/H2O2 solution volume. The results illustrate that the NO removal efficiency increases with the increasing of H2O2 initial concentration or UV lamp power. Meanwhile, a lower NO initial content or a higher TiO2/H2O2 solution volume will result in higher NO removal efficiency. In addition, oxygen volume fraction has a little effect. The highest NO removal efficiency is achieved at the TiO2 content of 0.75 g/L, H2O2 initial concentration of 2.5 mol/L, UV lamp power of 36 W, NO initial content of 206×10−6 and TiO2/H2O2 solution volume of 600 mL. It is beneficial for the development and application of NO removal from coal-fired flue gas with UV/TiO2/H2O2 process.

  6. 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

    The use of aqueous ammonia is a promising option to capture carbon dioxide from the flue gas of coal-fired power plants. Compared to a capture process using monoethanolamine (MEA), the use of ammonia can reduce the heat requirement of the CO2 desorption significantly, although an additional effort...... is necessary to provide the cooling of the process. To allow for a fair evaluation of the integration of this CO2 capture process into a power plant process, an overall process evaluation is carried out. The use of detailed models of the power plant, of the compressor and of the CO2 capture process enables...... the calculation of the power loss due to the steam extraction as well as due to the required auxiliary power for CO2 compression, solvent and cooling pumps and mechanical chillers. To study the influence of the cold end of the process, two power plants with different cooling water temperatures are analysed...

  7. 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...

  8. Multi-organ dysfunction in scrub typhus

    Directory of Open Access Journals (Sweden)

    Praveen Kumar Arinaganhalli Subbanna

    2012-01-01

    Full Text Available Scrub typhus is an acute, febrile zoonosis, caused by an obligate intracellular bacterium Orientia tsutsugamushi (O tsutsugamushi. The disease is of greatest public health importance in rural areas of Asia and in Western Pacific Islands. The clinical manifestations of the disease range from sub-clinical disease to an organ failure. The various complications known with this disease are jaundice, renal failure, pneumonitis, acute respiratory distress syndrome (ARDS, septic shock, myocarditis and meningo-encephalitis. The complications of scrub typhus usually develop after the 1 st week of illness. We report a 60-year-old farmer with scrub typhus, who presented with multi-organ dysfunction and recovered completely with treatment.

  9. Wet scrubbing of biomass producer gas tars using vegetable oil

    Science.gov (United States)

    Bhoi, Prakashbhai Ramabhai

    experimental data from the wet scrubbing system would be useful in the design and operation of a pilot scale vegetable oil based system. The process model, validated using experimental data, would be a key design tool for the design and optimization of a pilot scale vegetable oil based system.

  10. Rhabdomyolysis in scrub typhus: An unusual presentation

    Directory of Open Access Journals (Sweden)

    Bhatrahalli Ashok Praveen Kumar

    2013-01-01

    Full Text Available Scrub typhus is the most common zoonosis of public health importance in rural areas of Asia, Northern Australia and Pacific Islands. The clinical spectrum of the disease varies from acute febrile illness to multi-organ involvement with systemic complications. Delay in diagnosis and treatment often lead to increased morbidity and mortality. Rhabdomyolysis is a rare complication seen in an infectious disease. We report a 50-year-old farmer with scrub typhus presented with rhabdomyolysis and acute renal failure who succumbed to the disease in hospital.

  11. Scrub Typhus Meningitis in South India — A Retrospective Study

    OpenAIRE

    Viswanathan, Stalin; Muthu, Vivekanandan; Iqbal, Nayyar; Remalayam, Bhavith; George, Tarun

    2013-01-01

    Background Scrub typhus is prevalent in India although definite statistics are not available. There has been only one study on scrub typhus meningitis 20 years ago. Most reports of meningitis/meningoencephalitis in scrub typhus are case reports Methods A retrospective study done in Pondicherry to extract cases of scrub typhus admitted to hospital between February 2011 and January 2012. Diagnosis was by a combination of any one of the following in a patient with an acute febrile illness- a pos...

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

    International Nuclear Information System (INIS)

    Bench-top feasibility studies with Hanford single-shell tank (SST) simulants, using a new, low-temperature (50 to 60C) process for converting nitrate to ammonia and ceramic (NAC), have conclusively shown that between 85 to 99% of the nitrate can be readily converted. In this process, aluminum powders or shot can be used to convert alkaline, nitrate-based supernate to ammonia and an aluminum oxide-sodium aluminate-based solid which might function as its own waste form. The process may actually be able to utilize already contaminated aluminum scrap metal from various DOE sites to effect the conversion. The final, nearly nitrate-free ceramic-like product can be pressed and sintered like other ceramics. Based upon the starting volumes of 6.2 and 3.1 M sodium nitrate solution, volume reductions of 50 to 55% were obtained for the waste form produced, compared to an expected 35 to 50% volume increase if the Hanford supernate were grouted. Engineering data extracted from bench-top studies indicate that the process will be very economical to operate, and data were used to cost a batch, 1,200-kg NO3/h plant for working off Hanford SST waste over 20 years. Their total process cost analysis presented in the appendix, indicates that between $2.01 to 2.66 per kilogram of nitrate converted will be required. Additionally, data on the fate of select radioelements present in solution are presented in this report as well as kinetic, operational, and control data for a number of experiments. Additionally, if the ceramic product functions as its own waste form, it too will offer other cost savings associated with having a smaller volume of waste form as well as eliminating other process steps such as grouting

  13. Scrub typhus with bilateral pneumonitis: a case report

    OpenAIRE

    P. Venkata Krishna; Shaik Moulali; Shaik Ahmed

    2014-01-01

    Scrub typhus caused by Orientia tsutsugamushi is an uncommon cause of pneumonitis. We report a case of scrub typhus presenting with bilateral pneumonitis, left ventricular dysfunction and eschar. The present case reiterates the importance of careful physical examination in the early diagnosis of scrub typhus as aetiological cause.

  14. Scrub typhus with bilateral pneumonitis: a case report

    Directory of Open Access Journals (Sweden)

    P. Venkata Krishna

    2014-04-01

    Full Text Available Scrub typhus caused by Orientia tsutsugamushi is an uncommon cause of pneumonitis. We report a case of scrub typhus presenting with bilateral pneumonitis, left ventricular dysfunction and eschar. The present case reiterates the importance of careful physical examination in the early diagnosis of scrub typhus as aetiological cause.

  15. 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.)

  16. The Surgical Scrub. Learning Activity Package.

    Science.gov (United States)

    Runge, Lillian

    This learning activity package on the surgical scrub is one of a series of 12 titles developed for use in health occupations education programs. Materials in the package include objectives, a list of materials needed, a list of definitions, information sheets, reviews (self evaluations) of portions of the content, and answers to reviews. These…

  17. FLY ASH RECYCLE IN DRY SCRUBBING

    Science.gov (United States)

    The paper describes the effects of fly ash recycle in dry scrubbing. (Previous workers have shown that the recycle of product solids improves the utilization of slaked lime--Ca(OH)2--for sulfur dioxide (SO2) removal by spray dryers with bag filters.) In laboratory-scale experimen...

  18. Acute pancreatitis due to scrub typhus

    Directory of Open Access Journals (Sweden)

    Atif Shaikh Iqbal Ahmed

    2014-01-01

    Full Text Available Scrub typhus is endemic in large parts of India and can cause multi-organ failure and death. Acute pancreatitis as a complication is very rare and is potentially fatal. This case series describes seven adult patients who presented with an acute febrile illness and were diagnosed to have scrub typhus with acute pancreatitis. The mean age of the seven patients with acute pancreatitis was 49.4 years, and mean duration of fever prior to presentation was 7.7 days. All seven patients had abdominal pain, and three had a pathognomonic eschar. The mean serum lipase level was 1,509 U/L (normal value: <190 U/L and the mean serum amylase level was 434 U/L (normal value: <200 U/L. Six patients had evidence of multi-organ dysfunction. Hematological and respiratory system dysfunction was seen in five patients, hepatic and renal dysfunction in four, and central nervous system dysfunction in three patients. Three patients who had ≥4 organs involved, died (mortality rate: 42.8%. Our case series shows that pancreatitis in scrub typhus is an extremely rare complication and when present, is associated with increased mortality (42.8%. Physicians may be familiar with the various complications of scrub typhus but less so with acute pancreatitis and hence may be underdiagnosed.

  19. Scrub typhus with typical cutaneous lesion

    Directory of Open Access Journals (Sweden)

    Sridhar MS

    2014-07-01

    Full Text Available A patient with scrub typhus was successfully treated with doxycycline following ‘spot diagnosis’ based on the presence of typical eschar in association with fever. The diagnosis was promptly suspected at the first referral consultation. Early diagnosis and treatment are important because this disease can be associated with considerable morbidity and simple effective treatment is easily available.

  20. Scrub typhus with typical cutaneous lesion

    OpenAIRE

    Sridhar MS; Jahangeer S

    2014-01-01

    A patient with scrub typhus was successfully treated with doxycycline following ‘spot diagnosis’ based on the presence of typical eschar in association with fever. The diagnosis was promptly suspected at the first referral consultation. Early diagnosis and treatment are important because this disease can be associated with considerable morbidity and simple effective treatment is easily available.

  1. Radionuclide scrubbing in water pools: Bubble hydrodynamics

    International Nuclear Information System (INIS)

    In assessing the severity of degraded core accidents in light water reactors, limited credit is taken currently for scrubbing of fission products, either vapors or aerosols, in water pools. The development and use of more realistic scrubbing decontamination factors (DF's) could have a significant effect on the perceived safety of nuclear power plants. In order to provide a technique for calculating more realistic scrubbing DF's, the Electric Power Research Institute (EPRI) is sponsoring a program which includes development of an analytical model for scrubbing of fission product aerosols from steam/noncondensible gas mixtures injected into subcooled or saturated water pools under appropriate accident conditions. Battelle-Columbus is carrying out experiments designed to provide data for development and validation of the predictive model. Key hydrodynamic features in characterizing the transfer of aerosol from the incoming gas phase to the liquid pool include the interphase contact time and the interfacial area available for transfer. Hydrodynamic parameters which affect these key features were varied over ranges defined by analyses of several degraded core accidents carried out with the MARCH computer code. This paper presents the results of the first phase of the experimental program, a study of hydrodynamics of steam/noncondensible gas mixtures injected into a water pool through a single orifice

  2. 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...

  3. Pool scrubbing models for iodine components

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K. [Battelle Ingenieurtechnik GmbH, Eschborn (Germany)

    1996-12-01

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs.

  4. Pool scrubbing models for iodine components

    International Nuclear Information System (INIS)

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs

  5. 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.

  6. 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

  7. Macrofungi in the lateritic scrub jungles of southwestern India

    Directory of Open Access Journals (Sweden)

    A. A. Greeshma

    2015-09-01

    Full Text Available A pilot study on macrofungi in scrub jungles (with and without fire-impact in lateritic region of southwestern coast of India was carried out.  Out of 11 species in 10 genera recovered, six and five species were confined to scrub jungle and fire-impacted scrub jungle, respectively.  An ectomycorrhizal Amanita sp. was the most frequent in scrub jungle associated with exotic (Acacia auriculiformis and A. mangium and plantation (Anacardium occidentale trees.  Based on traditional knowledge, it is a highly edible and nutritional delicacy in the coastal regions.  Astraeus odoratus was another common ectomycorrhizal fungus in native trees Hopea ponga, which was recovered from the fire-impacted scrub jungle and is possibly edible.  Edible termite mound mushroom Termitomyces striatus was also common in the fire-impacted scrub jungle.  Chlorophyllum molybdites was the most frequent mushroom in the fire-impacted scrub jungle.  

  8. 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 is...

  9. Escrubagem da bauxita de Paragominas - PA: Parte 1: influência de variáveis operacionais na desagregação da bauxita Scrubbing process of the Miltonia 3 Bauxite - Part 1: influence of operating variables on bauxite disintegration

    Directory of Open Access Journals (Sweden)

    Jaime Henrique Barbosa da Costa

    2012-06-01

    Full Text Available O objetivo desse trabalho foi investigar a influência de variáveis operacionais na geração de finos (material com granulometria menor que 0,037 mm durante o processo de escrubagem, em escala de laboratório, da bauxita proveniente da jazida Miltônia 3 da Mina de Bauxita de Paragominas-PA, com vistas a fornecer subsídios para a modelagem matemática da operação. Para isso, foi realizada uma campanha de experimentos de escrubagem, em um tambor desagregador de laboratório, baseada em planejamento fatorial. Os parâmetros operacionais avaliados foram os seguintes: grau de enchimento, tempo de residência da polpa e velocidade de rotação. A variável de resposta selecionada foi a quantidade de finos (partículas menores que 0,037 mm no produto desagregado. O programa de experimentos permitiu a análise da influência de cada variável operacional selecionada na desagregação da bauxita. De acordo com os resultados obtidos, o parâmetro operacional que produziu o efeito mais significativo, na variável de resposta, foi o grau de enchimento.The aim of this study was to investigate the bauxite scrubbing process on samples from Miltonia 3, a Vale operation in the State of Pará, Brazil. The experimental program included the design of a standard laboratory test, from which parameters were derived for predicting the operation of a scrubber in steady state conditions. Three main variables were selected for the laboratory experimental program using the factorial design technique. These were load fraction, residence time and rotation speed. The amount of fines was determined through screening both the feed and the product of the scrubbing test. The former was considered to be a characteristic material, while the second was the dependent variable, i.e. the result of the scrubbing process. According to experiments, the load fraction was the most important variable for the scrubbing process.

  10. Biological Behavior of Anammox Process for Municipal Wastewater Treatment: Effect of Ammonia Removal and Other Parameters

    Directory of Open Access Journals (Sweden)

    R. Nabizadeh

    2012-09-01

    Full Text Available Historically, nitrogen compound due to major environmental and public health problems have been considered. Anaerobic ammonium oxidation processes were proposed by many advantages such as; novelty, promising method and cost-effective. In this work, we used of anommax process for a wastewater with high C:N ratios and the main parameter likes pH; temperature, NO2/NH4 ratio and behavior of COD, ammonium and nitrite during operation time of 55 days were evaluated. High efficiency in nitrite and ammonium removal is observed at pH values between 7.5 to 8 and operation times between 9 to 23 days. Furthermorethe variation of the nitrite/ammonium ratio done dependence to pH, and a higher ratio was associated with higher pH values. And lower values of NO2/NH4 ratio have occurred with decrease of pH at third phase of anommax process. The average elimination efficiency of COD was occurred about 89.22%, but the removal efficiency of COD in anommax reactor was obtained about 49.5%. Furthermorethe removal efficiency of ammonium and nitrite were provided about 50% for each.

  11. Dissolution of Plutonium Scrub Alloy and Anode Heel Materials in H-Canyon

    International Nuclear Information System (INIS)

    H-Canyon has a ''gap'' in dissolver operations during the last three months of FY03. One group of material to be processed during the gap is pre-existing scrub alloy material. There are 14 cans of material containing approximately 3.8 kilograms of plutonium. Of the 14 cans, it was anticipated that four cans contain salts, two cans contain anode heel materials, and eight cans contain scrub alloy buttons. H-Canyon desires to process the materials using a flowsheet similar to the SS and C (sand, slag and crucible) dissolution flowsheet used in F-Canyon. The materials will be loaded into carbon steel cans and then placed into aluminum metal charging bundles. Samples were sent to Savannah River Technology Center (SRTC) for characterization and flowsheet testing -- four MSE salts, two anode heels, and seven scrub alloy buttons. SRTC dissolved and characterized each of the samples. Two of them, originally thought to be MSE salts, were found to be graphite mold materials and were unsuitable for processing in H-Canyon. Characterization studies confirmed that the identification of the remaining items as MSE salts, scrub alloy buttons, and anode heel materials was correct. The MSE salts and anode heels solids are comprised primarily of plutonium, potassium, sodium and chloride. Both the MSE salts and anode heels left behind small amounts of residual solids. The scrub alloy buttons are comprised primarily of plutonium and aluminum. The solids dissolve readily with light, effervescent gas generation at the material surface and only trace amounts of NOx generation. Of the seven button samples, four dissolved completely. Two button samples contained small amounts of tantalum that did not dissolve. The last of the seven scrub alloy samples left a trace amount of residual plutonium solids. It is anticipated that the presence of undissolved fissile material is a function of where the sample was located relative to the button surface

  12. 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.

  13. 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

  14. 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

  15. 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

  16. Application of high frequency vibration screen to dewatering process in kunyang Phosphate scrubbing concentrator%高频脱水筛在昆阳磷矿擦洗磷精矿脱水中的应用

    Institute of Scientific and Technical Information of China (English)

    郭云

    2011-01-01

    通过对高频脱水筛的技术参数及矿浆浓度调节,使擦洗过程中回收的微细粒级精矿最终水分含量小于14%,满足干式堆放的要求.%The pulp concentration technology parameters of type high frequency vibration screen were measured. Miorofine concentrate pulpof scrubbing can be reduced under 14 %,which can beachieved the surface dispoalresults.

  17. 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

  18. Scrub Typhus:Jammu Outbreak-2009

    Directory of Open Access Journals (Sweden)

    Annil Mahajan,D.S Jasrotia,R.S. Charak*,Tejinder Kumar,P.L.Bhagat,Neeraj Sharma,BB Gupta

    2010-04-01

    Full Text Available This is a first report of 20 adult cases describing clinical feature, epidemiological profile and treatment outcomeof clinically diagnosed scrub typhus confirmed by test for antibodies (IgM to O.tsutsugamushi using ELISAkit. Majority of the cases belonged to the district Rajouri (45% froming hilly & rural belts.Outbreak wasAutumn Winter type as all cases reported in month of September and October. The common clinical featureswere fever 100%, myalgia 50%, headache 30%, conjunctival congestion 30%, eschar 35%, rash 25%,lymphadenopathy 45%, splenomegaly 40%, hepatomegaly 40%, edema 25%, ARDS 35%, altered sensorium10%, hypotension 20% & metrorrhagia in 5% of patients. Use of Immunological test helped to establishdiagnosis of scrub typhus.Thus all the cases were managed successfully without any mortality with doxycyclineand or azithromycine & one with addition of rifampicin.

  19. Pediatric scrub typhus in Indian Himalayas

    OpenAIRE

    S. K. Mahajan; Rolain, J.M.; Sankhyan, N.; R K Kaushal; Raoult, Didier

    2008-01-01

    To retrospectively confirm the suspected rickettsial disease (Scrub typhus) using a gold standard diagnostic test i.e. microimmunofluorescence in pediatric patients with acute febrile illness of unknown etiology. Two serological tests, Weil-Felix and Microimmunofluorescence were used to confirm infection. All five children had fever, vomiting and generalized lymphadenopathy, but none had eschar or rash. One was cured with doxycycline, remaining four patients treated with azithromycin and one ...

  20. Scrub typhus presenting as an acute abdomen

    OpenAIRE

    PP Abhilash Kundavaram; Sohini Das; M Varghese George

    2014-01-01

    Scrub typhus is a mite-borne infectious disease caused by Orientia tsutsugamushi, which presents as an acute febrile illness with headache, myalgia, breathlessness, and an eschar, a pathognomonic sign, in a varying proportion of patients. However, this illness can present unusually with fever and severe abdominal pain mimicking acute abdomen. A careful search for an eschar in all patients with an acute febrile illness would provide a valuable diagnostic clue and avoid unnecessary investigatio...

  1. Scrub typhus presenting as an acute abdomen

    Directory of Open Access Journals (Sweden)

    PP Abhilash Kundavaram

    2014-01-01

    Full Text Available Scrub typhus is a mite-borne infectious disease caused by Orientia tsutsugamushi, which presents as an acute febrile illness with headache, myalgia, breathlessness, and an eschar, a pathognomonic sign, in a varying proportion of patients. However, this illness can present unusually with fever and severe abdominal pain mimicking acute abdomen. A careful search for an eschar in all patients with an acute febrile illness would provide a valuable diagnostic clue and avoid unnecessary investigations and surgical exploration.

  2. Surgical hand hygiene: scrub or rub?

    Science.gov (United States)

    Widmer, A F

    2013-02-01

    Surgical hand hygiene is standard care prior to any surgical procedure. Per-operative glove punctures are observed in almost 30% of all interventions, and a risk factor for postoperative infections. In the past, washing hands with antimicrobial soap and water (surgical scrub) was the norm, mainly with chlorhexidine or iodine. More recently, alcohol-based hand rub has been successfully introduced, showing greater effectiveness, less irritation to the hands, and requiring less time than washing hands. All products should have a remnant effect that delays microbial growth under the gloved hand. Some of the alcohol-based compounds are effective (as determined by the European Norm EN 12791) within 90 s whereas others require 3-5 min, similar to the scrub. The short procedure relies heavily on proper technique and timing, since lowering the exposure time to bacterial killing. Today, surgical hand hygiene should meet EN 12791 in Europe, or other standards, such as the US Food and Drug Administration tentative final monograph norm in the USA. It is best performed by using an alcohol-based hand rub, but a scrub with chlorhexidine-containing soap also meets these standards. PMID:23453175

  3. 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.

  4. Electron Cloud and Scrubbing Studies for the LHC

    CERN Document Server

    Iadarola, G; Baglin, V; Bartosik, H; Esteban Muller, J E; Rumolo, G; Shaposhnikova, E; Tavian, L; Zimmermann, F; Dominguez, O; Maury Cuna, GHI

    2013-01-01

    Electron cloud build-up resulting from beam-induced multipacting is one of the major limitations for the operation of the LHC with beams with close bunch spacing. Electron clouds induce unwanted pressure rise, heat loads on the beam screens of the superconducting magnets and beam instabilities. Operation with bunch spacing of 50 ns in 2011 and 2012 has required decreasing the Secondary Electron Yield of the beam screens below the multipacting threshold for beams with this bunch spacing. This was achieved by continuous electron bombardment induced by operating the machine with high intensity beams with 50 and 25 ns spacing during dedicated periods at injection energy (450 GeV) and at top energy (3.5 and 4 TeV). The evolution of the Secondary Electron Yield during these periods, in different sections of the machine, can be estimated by pressure rise, heat load and by bunch-by-bunch RF stable phase measurements. The experimental information on the scrubbing process will be discussed and a possible “scrubbing s...

  5. Application of Bacterial Cellulose (BC) in Natural Facial Scrub

    OpenAIRE

    Norhasliza Hasan; Dayang Radiah Awang Biak; Suryani Kamarudin

    2012-01-01

    A new facial scrub containing only natural ingredients and powdered bacterial cellulose (BC) was formulated. The other ingredients used in the formulation include powdered glutinous rice, aloe vera extract, ascorbic acid (Vitamin C) powder and olive oil. The rheological behaviours of the formulated and commercial facial scrubs were tested using plate and plate rheometer. Both formulated and commercial facial scrubs shows shear thinning  behaviour (non-Newtonian liquid). The formulated facial ...

  6. Usefulness of Eschar PCR for Diagnosis of Scrub Typhus

    OpenAIRE

    Lee, Seung-Hyun; Kim, Dong-Min; Cho, Young Shin; Yoon, Sung Ho; Shim, Soo Kyoung

    2006-01-01

    We report here on the case of a child who was infected with scrub typhus, and we made the diagnosis according to the serology and by performing PCRs on the child's eschar. The patient was treated with azithromycin, and he did not experience any complications. Performing nested PCR on the eschar might be both a rapid diagnostic test for scrub typhus in the early acute stage and a differential test as to whether or not a scab is a scrub typhus eschar.

  7. Eschar in scrub typhus: A valuable clue to the diagnosis

    OpenAIRE

    A P Kundavaram; A J Jonathan; S D Nathaniel; G M Varghese

    2013-01-01

    Background: Scrub typhus is an acute febrile illness widely prevalent in the ′tsutsugamushi triangle′ region of the world. Clinical features include fever, myalgia, headache, rash, and a pathognomonic eschar. An eschar is formed by the bite of chigger mite that inoculates the causative agent of Scrub typhus Orientia tsutsugamushi. The aim of this study is to determine the most common sites of eschars over the bodies of patients with Scrub typhus. Materials and Methods: In a retrospective anal...

  8. Clinical and laboratory findings associated with severe scrub typhus

    OpenAIRE

    Choi Seong-Hyung; Kim Seok; Kim Dong-Min; Yun Na

    2010-01-01

    Abstract Background Scrub typhus is a mite-borne bacterial infection of humans caused by Orientia tsutsugamushi that causes a generalized vasculitis that may involve the tissues of any organ system. The aim of this study was to identify factors associated to severe complications from scrub typhus. Methods We conducted this prospective, case-control study on scrub typhus patients who presented to the Department of Internal Medicine at Chosun University Hospital between September, 2004 and Dece...

  9. The Rapid Effectiveness of Minocycline against Scrub Typhus Meningoencephalitis.

    Science.gov (United States)

    Naoi, Tameto; Shimazaki, Haruo; Sawada, Mikio

    2016-01-01

    Scrub typhus is associated with various clinical symptoms. However, the pathogenesis of scrub typhus infection remains to be elucidated. A 73-year-old man was admitted to our hospital with consciousness disturbance and suspected meningoencephalitis. The patient's laboratory data showed deterioration and were indicative of hemophagocytic lymphohistiocytosis (HLH). A whole body examination to detect the trigger disease revealed an eschar, which is a characteristic of scrub typhus, on his back. His symptoms showed dramatic improvement after the administration of minocycline (MINO). This case report highlights that the clinical course of a case of scrub typhus meningoencephalitis that was cured with MINO. PMID:27041169

  10. 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...

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

    Science.gov (United States)

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

    1983-10-01

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

  12. Acute Q Fever and Scrub Typhus, Southern Taiwan

    OpenAIRE

    Lai, Chung-Hsu; Chen, Yen-Hsu; Lin, Jiun-Nong; Chang, Lin-Li; Chen, Wei-Fang; Lin, Hsi-Hsun

    2009-01-01

    Acute Q fever and scrub typhus are zoonoses endemic to southern Taiwan. Among the 137 patients with acute Q fever (89, 65.0%) or scrub typhus (43, 31.4%), we identified 5 patients (3.6%) who were co-infected with Coxiella burnetii and Orientia tsutsugamushi.

  13. Seroprevalence of Scrub typhus at a tertiary care hospital in Andhra Pradesh

    Directory of Open Access Journals (Sweden)

    A Ramyasree

    2015-01-01

    Full Text Available Introduction: Scrub typhus is a rickettsial infection which is caused by Orientia tsutsugamushi and transmitted by the bite of the chigger of a mite. Delay in diagnosis can be fatal otherwise the treatment is simple, doxycycline being the drug of choice. Indirect immunoflurescence is considered gold standard but it is not used in India as it is costly and also not available. There is need for rapid, economic and simple test for the diagnosis of scrub typhus. This study was taken up to study the seroprevalence of scrub typhus in Andhra Pradesh and to compare two commonly used serological methods; rapid test and IgM ELISA. Materials and methods: This is a prospective study in which 100 serum samples from clinically suspected cases collected over a period of 3 months were processed for the detection of IgM antibodies for scrub typhus by ELISA and Rapid test. Samples were also tested for leptospirosis and dengue fever which the other common causes of fever prevalent in this region. Results: Total number of samples processed was 100 of which 52 were males and 48 females. Among the hundred samples 39 were seropositive. Positivity was higher in the age group of patients between 16 and 30 yrs of age. There was 97% correlation between ELISA and rapid method. Of the 100 samples only three samples positive by ELISA were negative by rapid method. Fever was the most common manifestation and there was no eschar and no mortality reported. Conclusion: Scrub typhus should be included in the differential diagnosis of fever of unknown origin along with dengue, malaria and leptospirosis which are the other common endemic infections in this part of the country.

  14. SCRUB versus trade: Enemies or allies?

    International Nuclear Information System (INIS)

    Under the 1990 Clean Air Act Amendments (CAAA), scrubbing and emission allowance trading will play complementary roles. This paper reviews Phase I announced strategies and presents projections of technology controls, coal switching and industry-wide SO2 removal costs under different assumptions about trading. The principal uncertainties characterizing today's planning environment are discussed -- ranging from changing expectations for fuel costs to swings in allowance prices and questions about regulation and new operating procedures. Economic forecasting is difficult. A clearer picture of Phase 2 strategies is emerging from EPRI's integrated analysis of fuel, technology and allowance markets -- based on collaboration between A. Van Horn and K. White (management consultants) and T. Hewson (Energy Ventures Analysis). About half the SO2 reductions required in Phase 2 are likely to come from technology controls and half from coal switching. With trading, the highest cost open-quotes scrubsclose quotes and open-quotes switchesclose quotes can be avoided, more upgrading of low-cost scrubbing is expected, and the role of switching grows to a small extent. Additional benefits from trading, averaging and banking allowances are: better sequencing of technology controls, less stringent specs for equipment, and added flexibility/risk-sharing opportunities in contract arrangements

  15. Orthogonal Test About Biogas Upgrading by Pressured Water Scrubbing

    Institute of Scientific and Technical Information of China (English)

    HUANG Li; JIAO Youzhou; LEI Tingzhou; ZHANG Quanguo

    2010-01-01

    Biogas is a kind of regenerable energy which is inexpensive and friendly to the environment, but the potential of biogas is difficult to develop fully in China, for most biogas have badly qualities and the utilization of it is monotonous. The suitable operation term about biogas upgrading by pressurized water scrubbing was researched through the orthogonal test in this study. Two sorts of scrubber packing included the random multidimensional hollow sphere packing and the structured screen packing were also used, and the effects of experiment factors included packing, water temperature, gas flow speed, water flow speed and washing pressure were studied. The results showed that better effect was got when the screen structured packing was used; all the five test factors affected the processing significantly in the arrange as before and had better and better significant effects.

  16. Scrub Typhus Incidence Modeling with Meteorological Factors in South Korea

    Directory of Open Access Journals (Sweden)

    Jaewon Kwak

    2015-06-01

    Full Text Available Since its recurrence in 1986, scrub typhus has been occurring annually and it is considered as one of the most prevalent diseases in Korea. Scrub typhus is a 3rd grade nationally notifiable disease that has greatly increased in Korea since 2000. The objective of this study is to construct a disease incidence model for prediction and quantification of the incidences of scrub typhus. Using data from 2001 to 2010, the incidence Artificial Neural Network (ANN model, which considers the time-lag between scrub typhus and minimum temperature, precipitation and average wind speed based on the Granger causality and spectral analysis, is constructed and tested for 2011 to 2012. Results show reliable simulation of scrub typhus incidences with selected predictors, and indicate that the seasonality in meteorological data should be considered.

  17. 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

  18. 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.

  19. Masticophis flagellum selects florida scrub habitat at multiple spatial scales

    Science.gov (United States)

    Halstead, B.J.; Mushinsky, H.R.; McCoy, E.D.

    2009-01-01

    The use of space by individual animals strongly influences the spatial extent, abundance, and growth rates of their populations. We analyzed the spatial ecology and habitat selection of Masticophis flagellum (the coachwhip) at three different scales to determine which habitats are most important to this species. Home ranges and mean daily displacements of M. flagellum in Florida were large compared to individuals in other populations of this species. Home ranges contained a greater proportion of Florida scrub habitat than did the study site as a whole, and individuals selected Florida scrub habitat within their home ranges. For both selection of the home range within the study site and selection of habitats within the home range, mesic cutthroat and hydric swamp habitats were avoided. Standardized selection ratios of Florida scrub patches were positively correlated with lizard abundance. Several non-mutually exclusive mechanisms, including foraging success (prey abundance, prey vulnerability, and foraging efficiency), abundance of refugia, and thermoregulatory opportunity may underlie the selection of Florida scrub by M. flagellum. Historic rarity and anthropogenic loss and fragmentation of Florida scrub habitat, coupled with the long-distance movements, large home ranges, and selection of Florida scrub by M. flagellum, indicate that large contiguous tracts of land containing Florida scrub will be essential for the persistence of M. flagellum in central Florida. ?? 2009 by The Herpetologists' League, Inc.

  20. Eschar in scrub typhus: A valuable clue to the diagnosis

    Directory of Open Access Journals (Sweden)

    A P Kundavaram

    2013-01-01

    Full Text Available Background: Scrub typhus is an acute febrile illness widely prevalent in the ′tsutsugamushi triangle′ region of the world. Clinical features include fever, myalgia, headache, rash, and a pathognomonic eschar. An eschar is formed by the bite of chigger mite that inoculates the causative agent of Scrub typhus Orientia tsutsugamushi. The aim of this study is to determine the most common sites of eschars over the bodies of patients with Scrub typhus. Materials and Methods: In a retrospective analysis, we examined a total of 418 patients who presented to Christian Medical College, Vellore between 2009 and 2012 with an acute febrile illness and an eschar on clinical examination and confirmed to have scrub typhus with a positive Scrub typhus IgM ELISA test. We studied the distribution of eschars over the bodies of 418 patients with Scrub typhus. Results: There was a significant difference in the distribution of eschars between males and females with a preponderance of the chest and abdomen (42.3% among females and the axilla, groin and genitalia (55.8% in males. Some unusual sites of an eschar were the cheek, ear lobe and dorsum of the feet. Conclusion: The eschar is the most useful diagnostic clue in patients with acute febrile illness in areas endemic for Scrub typhus and therefore should be thoroughly examined for its presence especially over the covered areas such as the groin, genitalia, infra-mammary area and axilla.

  1. 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.

  2. Review and assessment of pool scrubbing models

    International Nuclear Information System (INIS)

    Decontamination of fission products bearing bubbles as they through aqueous pools becomes a crucial phenomenon for source term evaluation of hypothetical risk dominant sequences of Light Water Reactors. In the present report a peer review and assessment of models encapsulated in SPARC andBUSCA codes is presented. Several aspects of pool scrubbing have been addressed: particle removal, fission product vapour retention and bubble hydrodynamics. Particular emphasis has been given to the close link between retention and hydrodynamics, from both modelling and experimental point of view. In addition, RHR and SGTR sequences were simulated with SPARC90 and BUSCA-AUG92 codes, and their results were compared with those obtained with MAAP 3.0B.As a result of this work, model capabilities and shortcomings have beenassessed and some areas susceptible of further research have been identified.(Author) 73 refs

  3. Review and assessment of pool scrubbing models

    International Nuclear Information System (INIS)

    Decontamination of fission products bearing bubbles as they pass through aqueous pools becomes a crucial phenomenon for source term evaluation of hypothetical risk dominant sequences of Light Water Reactors. In the present report a peer review and assessment of models encapsulated in SPARC and BUSCA codes is presented. Several aspects of pool scrubbing have been addressed: particle removal, fission product vapour retention and bubble hydrodynamics. Particular emphasis has been given to the close link between retention and hydrodynamics, from both modelling and experimental point of view. In addition, RHR and SGTR sequences were simulated with SPARC90 and BUSCA-AUG92 codes, and their results were compared with those obtained with MAAP 3.0B. As a result of this work, model capabilities and shortcomings have been assessed and some areas susceptible of further research have been identified. (Author) 73 refs

  4. 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

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

    Science.gov (United States)

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

    2016-01-01

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

  6. 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

  7. 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 with the...... 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...

  8. Metal regeneration of iron chelates in nitric oxide scrubbing

    Science.gov (United States)

    Chang, S.G.; Littlejohn, D.; Shi, Y.

    1997-08-19

    The present invention relates to a process of using metal particles to reduce NO to NH{sub 3}. More specifically, the invention concerns an improved process to regenerate iron (II) (CHELATE) by reduction of iron (II) (CHELATE) (NO) complex, which process comprises: (a) contacting an aqueous solution containing iron (II) (CHELATE) (NO) with metal particles at between about 20 and 90 C to reduce NO present, produce ammonia or an ammonium ion, and produce free iron (II) (CHELATE) at a pH of between about 3 and 8. The process is useful to remove NO from flue gas and reduce pollution. 34 figs.

  9. Pancreatic abscess following scrub typhus associated with multiorgan failure

    Institute of Scientific and Technical Information of China (English)

    Sun Young Yi; Jung Hyun Tae

    2007-01-01

    Clinical severity of scrub typhus ranges from mild to fatal. Acute pancreatitis with abscess formation is a rare complication among patients with scrub typhus. This paper reports a case of scrub typhus in a 75 years old man with acute pancreatitis with abscess formation and multiorgan failure. Abdominal computed tomography showed multiple infected pancreatic pseudocysts with peri-pancreatic infiltration. Multiorgan failure was successfully treated with doxycycline, ceftriaxone, and supportive management. The pancreatic abscess was successfully drained percutaneously and the sizes of pseudocysts decreased remarkably.

  10. 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

  11. 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...

  12. Cd1−xZnxS thin films with low Zn content obtained by an ammonia-free chemical bath deposition process

    International Nuclear Information System (INIS)

    Cd1−xZnxS 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 Cd1−xZnxS films were also observed as effects of adding Zn to the CdS lattice. Optical studies show that Cd1−xZnxS thin films with energy band gaps in the range from 2.48 to 2.65 eV were obtained. - Highlights: • Cd1−xZnxS 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 • Cd1−xZnxS films have energy band gap values from 2.48 to 2.65 eV

  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. 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.

  15. 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

  16. Monitoring the progress of LHC electron-cloud scrubbing by benchmarking simulations and pressure-rise observations

    CERN Document Server

    Dominguez, Octavio; Arduini, Gianluigi; Metral, Elias; Rumolo, Giovanni; Zimmermann, Frank

    2012-01-01

    Electron bombardment of a surface has been proven to reduce drastically the secondary electron yield of a material. This technique, known as scrubbing, provides a mean to suppress electron cloud build-up and its undesired effects (e.g. vacuum pressure rise, heat load, beam instabilities) in particle accelerators operating with intense beams. Its effectiveness has been already observed at the LHC. In this paper we present the latest observations on the vacuum chamber conditioning and a proposal to optimize the scrubbing process by means of the map formalism.

  17. Massive small bowel bleeding caused by scrub typhus in Korea

    OpenAIRE

    2010-01-01

    A 79-year-old man was diagnosed with scrub typhus based on fever, eschar, skin rash and a markedly elevated serum tsutsugamushi antibody and doxycycline was started. Five days later, hematochezia developed and multiple small bowel ulcerations with hemorrhage were seen on colonoscopy. Despite intensive therapy, the massive hematochezia worsened and the distal small bowel was resected. Multiple ulcerated lesions were identified pathologically as vasculitis caused by scrub typhus. This is the fi...

  18. Scrub Typhus with Sepsis and Acute Respiratory Distress Syndrome

    OpenAIRE

    Kurup, Asok; Issac, Aneesh; Loh, Jin Phang; Lee, Too Bou; Chua, Robert; Bist, Pradeep; Chao, Chien-Chung; Lewis, Michael; Gubler, Duane J.; Ching, Wei Mei; Ooi, Eng Eong; Sukumaran, Bindu

    2013-01-01

    Scrub typhus is a major infectious threat in the Asia-Pacific region. We report an unusual case of scrub typhus in a patient in Singapore who presented with sepsis and acute respiratory distress syndrome but lacked the pathognomonic eschar. The patient recovered after appropriate diagnosis and doxycycline treatment. Rickettsial diseases should be included in the differential diagnosis of febrile illnesses in regions where the diseases are endemic, and absence of eschar should not be the crite...

  19. A Case Series Of Scrub Typhus In Obstetrics

    OpenAIRE

    G K, Poomalar; R., Rekha

    2014-01-01

    Scrub typhus is endemic and re-emerging in eastern and southern Asia. Illness varies from mild and self-limiting to fatal. Only few studies were published about its effect in maternal and neonatal outcome. A retrospective analysis was done in six prenatal and two postnatal women with scrub typhus. Details about clinical presentation, investigations, treatment given, response to treatment and pregnancy outcome were collected. The common symptoms were fever with chills, vomiting, myalgia, heada...

  20. Clinical and laboratory findings associated with severe scrub typhus

    Directory of Open Access Journals (Sweden)

    Choi Seong-Hyung

    2010-04-01

    Full Text Available Abstract Background Scrub typhus is a mite-borne bacterial infection of humans caused by Orientia tsutsugamushi that causes a generalized vasculitis that may involve the tissues of any organ system. The aim of this study was to identify factors associated to severe complications from scrub typhus. Methods We conducted this prospective, case-control study on scrub typhus patients who presented to the Department of Internal Medicine at Chosun University Hospital between September, 2004 and December, 2006. Cases were 89 scrub typhus patients with severe complications and controls were 119 scrub typhus patients without severe complications. Results There were significant differences in the absence of eschar, white blood cell (WBC counts, hemoglobin, albumin, serum creatinine, fibrinogen, C-reactive protein (CRP, and active partial thromboplastin time (aPTT between the two groups. Multivariate analysis demonstrated that only the following four factors were significantly associated with the severe complications of scrub typhus: (1 age ≥ 60 years (odd ratio [OR] = 3.13, P = 0.002, confidence interval [CI] = 1.53-6.41, (2 the absence of eschar (OR = 6.62, P = 0.03, CI = 1.22-35.8, (3 WBC counts > 10, 000/mm3 (OR = 3.6, P = 0.001, CI = 1.65-7.89, and (4 albumin ≤ 3.0 g/dL (OR = 5.01, P = 0.004, CI = 1.69-14.86. Conclusions Our results suggest that clinicians should be aware of the potential for complications, when scrub typhus patients are older (≥ 60 years, presents without eschar, or laboratory findings such as WBC counts > 10, 000/mm3, and serum albumin level ≤ 3.0 g/dL. Close observation and intensive care for scrub typhus patients with the potential for complications may prevent serious complications with subsequent reduction in its mortality rate.

  1. 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...

  2. Application of Bacterial Cellulose (BC in Natural Facial Scrub

    Directory of Open Access Journals (Sweden)

    Norhasliza Hasan

    2012-01-01

    Full Text Available A new facial scrub containing only natural ingredients and powdered bacterial cellulose (BC was formulated. The other ingredients used in the formulation include powdered glutinous rice, aloe vera extract, ascorbic acid (Vitamin C powder and olive oil. The rheological behaviours of the formulated and commercial facial scrubs were tested using plate and plate rheometer. Both formulated and commercial facial scrubs shows shear thinning  behaviour (non-Newtonian liquid. The formulated facial scrub sample had a higher viscosity at low shear rates compared to the commercial facial scrub (459.7 Pa.s against 359.2 Pa.s at 10s-1, but had a nearly similar viscosity at high shear rates (197.2 Pa.s against 192 Pa.s at 25s-1. By adding preservative, the shelf life of the scrub was two times longer than that without preservatives. The  tested sample dried out after 10 minutes at room temperature (~30°C.

  3. DISTRIBUTION OF ESCHAR IN CHILDREN WITH SCRUB TYPHUS

    Directory of Open Access Journals (Sweden)

    Bahubali D

    2015-08-01

    Full Text Available Scrub typhus is caused by an intracellular bacterium, Orientia tsutsugamushi. It causes a disseminated vasculitic and perivascular inflammatory lesions. These lead to significant vascular leakage and end ‑ organ injury. Eschar is the site of inoculation. It is painless and non - pruritic. It is a useful indicator of the disease. We studied the scrub typhus children with eschar to describe its distribution. MATERIAL AND METHODS: This is a retrospective study done in tertiary care hospital. Study was done with aim of studying the distribution of eschar. Patients included in study are: confirmed to have scrub typhus with a positive Scrub typhus IgM ELISA test and presence of eschar, Children less than 18 years. Data collected regarding clinical profile of cases and eschar distribution. RESULTS: Totally 52 cases with eschar were included in the study. Commonest site of eschar was axilla followed by groin. Other common sites of eschar included abdomen and chest. CONCLUSION: Detection of eschar helps clinically to distinguish scrub typhus from other febrile illness. Knowledge of common eschar sites would be useful for early clinical diagnosis of scrub typhus.

  4. A case series of scrub typhus in obstetrics.

    Science.gov (United States)

    G K, Poomalar; R, Rekha

    2014-12-01

    Scrub typhus is endemic and re-emerging in eastern and southern Asia. Illness varies from mild and self-limiting to fatal. Only few studies were published about its effect in maternal and neonatal outcome. A retrospective analysis was done in six prenatal and two postnatal women with scrub typhus. Details about clinical presentation, investigations, treatment given, response to treatment and pregnancy outcome were collected. The common symptoms were fever with chills, vomiting, myalgia, headache and abdominal pain. Typical features of eschar and lymphadenopathy were noted in only two cases. Two patients presented with jaundice and altered liver function test. Two patients presented with breathlessness. One patient developed oligohydramnios. Two postnatal women developed scrub typhus following blood transfusion for postpartum haemorrhage. Because of its high prevalence, scrub typhus should be included in fever investigations in endemic areas, even in the absence of eschar. Early diagnosis of cases will help in less severe organ damage and easy recovery with antibiotics. Few evidences state that scrub typhus can spread through blood transfusion. Correlation between blood transfusion and scrub typhus has to be further evaluated. PMID:25653996

  5. Mass transfer in the absorption of SO2 and NOx using aqueous euchlorine scrubbing solution

    Institute of Scientific and Technical Information of China (English)

    DESHWAL Bal-Raj; LEE Hyung-Keun

    2009-01-01

    Attempts have been made to generate euchlorine gas by chlorate-chloride process and to utilize it further to clean up SO2 and NOx from the flue gas in a lab scale bubbling reactor.Preliminary experiments were carried out to determine the gas and liquid phase mass transfer coefficients and their correlation equations have been established.Simultaneous removal of SO2 and NOx from the simulated flue gas using aqueous euchlorine scrubbing solution has been investigated.Euchlorine oxidized NO into NO2 completely and the later subsequently absorbed into the scrubbing solution in the form of nitrate.SO2 removal efficiency of around 100% and NOx removal efficiency of around 72 % were achieved under optimized conditions.Mass balance has been confirmed by analyzing the sulfate, nitrate, euchlorine and chloride ion using ion chromatograph/auto-titrator and comparing it with their corresponding calculated values.

  6. 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...

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

    Science.gov (United States)

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

    1983-12-01

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

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

    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.

  9. Influence of attrition scrubbing, ultrasonic treatment, and oxidant additions on uranium removal from contaminated soils

    International Nuclear Information System (INIS)

    As part of the Uranium in Soils Integrated Demonstration Project being conducted by the US Department of Energy, bench-scale investigations of selective leaching of uranium from soils at the Fernald Environmental Management Project site in Ohio were conducted at Oak Ridge National Laboratory. Two soils (storage pad soil and incinerator soil), representing the major contaminant sources at the site, were extracted using carbonate- and citric acid-based lixiviants. Physical and chemical processes were used in combination with the two extractants to increase the rate of uranium release from these soils. Attrition scrubbing and ultrasonic dispersion were the two physical processes utilized. Potassium permanganate was used as an oxidizing agent to transform tetravalent uranium to the hexavalent state. Hexavalent uranium is easily complexed in solution by the carbonate radical. Attrition scrubbing increased the rate of uranium release from both soils when compared with rotary shaking. At equivalent extraction times and solids loadings, however, attrition scrubbing proved effective only on the incinerator soil. Ultrasonic treatments on the incinerator soil removed 71% of the uranium contamination in a single extraction. Multiple extractions of the same sample removed up to 90% of the uranium. Additions of potassium permanganate to the carbonate extractant resulted in significant changes in the extractability of uranium from the incinerator soil but had no effect on the storage pad soil

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

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2015-01-01

    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...

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

    International Nuclear Information System (INIS)

    The paper presented an efficient integrated physicochemical process, which consists of chemical precipitation and air stripping, for the simultaneous removal of NH3-N, total P and COD from anaerobically digested piggery wastewater. In the integrated process, Ca(OH) 2 was used as the precipitant for NH4+, PO43- and organic phosphorous compounds, and as the pH adjuster for the air stripping of residual ammonia. The possibility of the suggested process and the related mechanisms were first investigated through a series of equilibrium tests. Laboratory scale tests were carried out to validate the application possibility of the integrated process using a new-patented water sparged aerocyclone reactor (WSA). The WSA could be effectively used for the simultaneous removal of NH3-N, total P and COD. 3 g/L of Ca(OH) 2 is a proper dosage for the simultaneous removal. The simultaneous removal of NH3-N, total P and COD in the WSA reactor could be easily optimized by selecting a proper air inlet velocity and a proper jet velocity of the liquid phase. In all the cases, the removal efficiencies of the NH3-N, total P and COD were over 91%, 99.2% and 52% for NH3-N, total P and COD, respectively. The formed precipitates in the process could be easily settled down from the suspension system. Therefore, the integrated process provided an efficient alternative for the simultaneous removal of NH3-N, total P and COD from the wastewater.

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

    Science.gov (United States)

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

    2014-01-01

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

  13. 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.

  14. 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...

  15. CansolvR system for sulfur dioxide scrubbing. 5. ed.

    International Nuclear Information System (INIS)

    Cansolv Technologies, a Montreal-based company, developed the CansolvR system scrubbing technology. The technology is based on an aqueous amine solvent in a conventional amine treater process flowsheet configuration which allows for high-efficiency removal of sulphur dioxide from a wide array of gas streams. The following sectors can benefit from the application of the CansolvR system: petroleum refining, natural gas sweetening, smelting of sulfide ores, power generation, pulp and paper plants, and industrial boilers. The by-product of this process is sulphur dioxide, a chemical used in pulping, corn wet milling, and a chemical reagent. The operation of three full-scale commercial reference plants began in 2002. The first commercial operation is a zinc smelter in Valleyfield, Quebec. The second commercial operation was at a chemical plant in Belgium, and the third was in Los Angeles at an oil refinery. Expectations were exceeded from those commercial applications of CansolvR system in terms of cost, removal efficiency, energy consumption, and solvent stability. 1 tab., 1 fig

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

    Science.gov (United States)

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

    2006-11-01

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

  17. The description of the copper deposition/dissolution process in ammonia buffer with the application of mathematical two-plate model

    International Nuclear Information System (INIS)

    The experimental Cu2+/Cu+/Cu0 system in ammonia buffer (pH = 9.25) has been investigated by cyclic voltammetry method and described by the advanced two-plate model with BET adsorption equation. A change of electrode properties during electrode process is included into the applied model. The model reproduces four one-electron peaks of electronation/deelectronation process together with a characteristic loop on cathodic part of CV response and covers 0.1; 0.2, 0.5; 1; 2; 5; 10; 20; 50 mM concentrations of Cu2+ at scan rate range 0.05–5 V/s. The values of elementary kinetic parameters have been determined, validated and discussed. It has been proved that CV technique and two-plate model is adequate to cover complete description of the deposition process for the wide range of concentration. The parameters of applied BET adsorption model coupled with kinetic parameters of electrochemical process model have been extensively discussed

  18. 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.

  19. Hybrid process for nitrogen oxides reduction

    Energy Technology Data Exchange (ETDEWEB)

    Epperly, W.R.; Sprague, B.N.

    1991-09-10

    This patent describes a process for reducing the nitrogen oxide concentration in the effluent from the combustion of a carbonaceous fuel. It comprises introducing into the effluent a first treatment agent comprising a nitrogenous composition selected from the group consisting of urea, ammonia, hexamethylenetetramine, ammonium salts of organic acids, 5- or 6-membered heterocyclic hydrocarbons having at least one cyclic nitrogen, hydroxy amino hydrocarbons, NH{sub 4}-lignosulfonate, fur-furylamine, tetrahydrofurylamine, hexamethylenediamine, barbituric acid, guanidine, guanidine carbonate, biguanidine, guanylurea sulfate, melamine, dicyandiamide, biuret, 1.1{prime}-azobisformamide, methylol urea, methylol urea-urea condensation product, dimethylol urea, methyl urea, dimethyl urea, calcium cyanamide, and mixtures thereof under conditions effective to reduce the nitrogen oxides concentration and ensure the presence of ammonia in the effluent; introducing into the effluent a second treatment agent comprising an oxygenated hydrocarbon at an effluent temperature of about 500{degrees} F. to about 1600{degrees} F. under conditions effective to oxidize nitric oxide in the effluent to nitrogen dioxide and ensure the presence of ammonia at a weight ratio of ammonia to nitrogen dioxide of about 1:5 to about 5:1; and contacting the effluent with an aqueous scrubbing solution having a pH of 12 or lower under conditions effective to cause nitrogen dioxide to be absorbed therein.

  20. 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.

  1. 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...

  2. Hydraulic Modeling of Novel Combined Nozzle for Pool Scrubbing System

    International Nuclear Information System (INIS)

    The particles are collected in the scrubbing liquid. Knowing that the particle is removed from the gas stream mainly by scrubbing phenomena, the filtration efficiency can be enhanced by enlarging the contact area between the scrubbing water and the gas/particle mixture (e.g. break the bulk of gas flow into fine bubbles) or by enlarging the contact time of them (e. g. increase the water pool depth). In this study, the novel design of the combined nozzle has been developed to minimize the size of the filtration system and to ensure the filtration efficiency over the wide range of operating conditions. The hydraulic simulation has been conducted to investigate the flow behavior inside of the nozzle prior to evaluate the filtering efficiency. The proto-typical combined nozzle has been modeling in CFD and simulated for different conditions. Preliminary CFD simulation is conducted to examine the effects of key features and the flow behaviors inside the combined nozzle

  3. Scrub typhus meningitis: An under-recognized cause of aseptic meningitis in India

    Directory of Open Access Journals (Sweden)

    Kundavaram Paul Prabhakar Abhilash

    2015-01-01

    Conclusions: In endemic regions, scrub typhus should be considered in the differential diagnosis of aseptic meningitis. Modest elevation of cells in the CSF with lymphocytic pleocytosis and multi-organ involvement may indicate scrub typhus meningitis/meningo-encephalitis.

  4. 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...

  5. Leukocytoclastic vasculitis and polyarthralgia in scrub typhus: An unusual presentation

    Directory of Open Access Journals (Sweden)

    Arinaganahalli Subbanna Praveen Kumar

    2013-10-01

    Full Text Available Scrub typhus is an acute, febrile zoonosis caused by an obligate intracellular bacterium Orientia tsutsugamushi. It is of greatest public health importance in tropical rural Asia. The clinical manifestations of the disease range from sub-clinical to fatal organ failure. The common symptoms are fever, chills, headache, myalgia, dry cough, lymphadenopathy and gastrointestinal disturbances. The first presentation with cutaneous vasculitis and polyarthralgia is rare and unusual. We report a case of scrub typhus that presented with cutaneous vasculitis and polyarthralgia, which is very unusual and patient recovered with doxycycline treatment.

  6. The effect of silver impregnation of surgical scrub suits on surface bacterial contamination

    OpenAIRE

    Freeman, A.I.; Halladay, L.J.; Cripps, P.

    2012-01-01

    Silver-impregnated fabrics are widely used for their antibacterial and antifungal effects, including for clinical clothing such as surgical scrub suits (scrubs). This study investigated whether silver impregnation reduces surface bacterial contamination of surgical scrubs during use in a veterinary hospital. Using agar contact plates, abdominal and lumbar areas of silver-impregnated nylon or polyester/cotton scrubs were sampled for surface bacterial contamination before (0 h) and after 4 and ...

  7. Is it time for brushless scrubbing with an alcohol-based agent?

    Science.gov (United States)

    Gruendemann, B J; Bjerke, N B

    2001-12-01

    The practice of surgical scrubbing in perioperative settings is changing rapidly. This article presents information about eliminating the traditional scrub brush technique and using an alcohol formulation for surgical hand scrubs. Also covered are antimicrobial agents, relevant US Food and Drug Administration classifications, skin and fingernail care, and implementation of changes. The article challenges surgical team members to evaluate a new and different approach to surgical hand scrubbing. PMID:11795059

  8. Scrub typhus in adults in a teaching hospital in north Karnataka, 2011-2012

    OpenAIRE

    Umesh G Rajoor; Shiddappa K Gundikeri; Jayaraj C Sindhur; M. Dhananjaya

    2013-01-01

    Background and Objectives: Scrub typhus is grossly under-diagnosed in India due to its non specific clinical presentation, limited awareness and low index of suspicion among clinicians, and lack of diagnostic facilities. As there is a resurgence of scrub typhus in this part of north Karnataka, an attempt is made to study the clinical prolife and complications of scrub typhus in adult patients. Materials and Methods: All cases of febrile illness diagnosed as scrub typhus over a period of 1 yea...

  9. Contrasting genetic structures in sister species of North American scrub-jays

    OpenAIRE

    McDonald, D. B.; Potts, W. K.; Fitzpatrick, J. W.; Woolfenden, G. E.

    1999-01-01

    Threatened Florida scrub-jays (Aphelocoma coerulescens breed communally, are restricted to xeric sandy scrub habitat, generally disperse fewer than three territory diameters. Closely related Western scrub-jays (A. californica) do not breed communally, have a broader habitat range, disperse greater distances, and are not threatened. We compared the genetic structure of 445 individuals in 11 populations in Florida with 157 individuals in eight populations of Western scrub-jays. At ten microsate...

  10. 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.

  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. 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...... nitrite oxidation only appeared in locations with minimal ammonia and nitrite levels. Nitrous oxide emission depended on anoxic microsites, and nitric oxide production was associated with nitrite accumulation. Water and biomass management appear to be the important tools for optimization of ammonia...

  13. 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

  14. 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...... microscopy and X-ray diffraction analysis. It is shown that the use of unsaturated hydrocarbon gas in nitrocarburising processes is a viable alternative to traditional nitrocarburising methods....

  15. Sample Results From The Extraction, Scrub, And Strip Test For The Blended NGS Solvent

    Energy Technology Data Exchange (ETDEWEB)

    Washington, A. L. II; Peters, T. B.

    2014-03-03

    This report summarizes the results of the extraction, scrub, and strip testing for the September 2013 sampling of the Next Generation Solvent (NGS) Blended solvent from the Modular Caustic Side-Solvent Extraction Unit (MCU) Solvent Hold Tank. MCU is in the process of transitioning from the BOBCalixC6 solvent to the NGS Blend solvent. As part of that transition, MCU has intentionally created a blended solvent to be processed using the Salt Batch program. This sample represents the first sample received from that blended solvent. There were two ESS tests performed where NGS blended solvent performance was assessed using either the Tank 21 material utilized in the Salt Batch 7 analyses or a simulant waste material used in the V-5/V-10 contactor testing. This report tabulates the temperature corrected cesium distribution, or DCs values, step recovery percentage, and actual temperatures recorded during the experiment. This report also identifies the sample receipt date, preparation method, and analysis performed in the accumulation of the listed values. The calculated extraction DCs values using the Tank 21H material and simulant are 59.4 and 53.8, respectively. The DCs values for two scrub and three strip processes for the Tank 21 material are 4.58, 2.91, 0.00184, 0.0252, and 0.00575, respectively. The D-values for two scrub and three strip processes for the simulant are 3.47, 2.18, 0.00468, 0.00057, and 0.00572, respectively. These values are similar to previous measurements of Salt Batch 7 feed with lab-prepared blended solvent. These numbers are considered compatible to allow simulant testing to be completed in place of actual waste due to the limited availability of feed material.

  16. Sample Results From The Extraction, Scrub, And Strip Test For The Blended NGS Solvent

    International Nuclear Information System (INIS)

    This report summarizes the results of the extraction, scrub, and strip testing for the September 2013 sampling of the Next Generation Solvent (NGS) Blended solvent from the Modular Caustic Side-Solvent Extraction Unit (MCU) Solvent Hold Tank. MCU is in the process of transitioning from the BOBCalixC6 solvent to the NGS Blend solvent. As part of that transition, MCU has intentionally created a blended solvent to be processed using the Salt Batch program. This sample represents the first sample received from that blended solvent. There were two ESS tests performed where NGS blended solvent performance was assessed using either the Tank 21 material utilized in the Salt Batch 7 analyses or a simulant waste material used in the V-5/V-10 contactor testing. This report tabulates the temperature corrected cesium distribution, or DCs values, step recovery percentage, and actual temperatures recorded during the experiment. This report also identifies the sample receipt date, preparation method, and analysis performed in the accumulation of the listed values. The calculated extraction DCs values using the Tank 21H material and simulant are 59.4 and 53.8, respectively. The DCs values for two scrub and three strip processes for the Tank 21 material are 4.58, 2.91, 0.00184, 0.0252, and 0.00575, respectively. The D-values for two scrub and three strip processes for the simulant are 3.47, 2.18, 0.00468, 0.00057, and 0.00572, respectively. These values are similar to previous measurements of Salt Batch 7 feed with lab-prepared blended solvent. These numbers are considered compatible to allow simulant testing to be completed in place of actual waste due to the limited availability of feed material

  17. Use of conventional sieve trays in ammonia-hydrogen exchange process for production of heavy water and the operating experience (Preprints No. PD-14)

    International Nuclear Information System (INIS)

    The sieve trays used in Heavy Water Plant at Talcher are simple and are free from any maintenance. Absence of pumps etc resulted in trouble-free installation and operation of these trays. Performance of the trays, has, however not been satisfactory due to the constraints of high foam height, reduced gas flow rates and higher pressure drop. These constraints may be removed for new trays by suitable modification of the tray geometry in the design stage like reduction of weir height, increase in tray spacing, change in hole diameter/spacing, reduction of design/flow rate per unit tray active area (i.e. increase in tray/tower diameter for same gas load) etc. Removal of the hydrodynamic limitations will permit operation at near design conditions of temperature, potassium amide concentration and gas flow rates. This is likely to improve the efficiency of the trays. Careful study of the operating behaviour of the sieve t rays and judicious modification of the tray geometry for future design may make the s ieve trays a useful contacting device in ammonia-hydrogen exchange process for heavy water production. (author). 1 tab ., 4 figs

  18. Ammonia synthesis at low temperatures

    DEFF Research Database (Denmark)

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

    2000-01-01

    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...... 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....

  19. 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

    methanogens are more robust to ammonia toxicity effect. It has been shown that bioaugmentation of a pure strain of a hydrogenotrophic methanogen (i.e. Methanoculleus bourgensis) in an ammonia inhibited continuous anaerobic reactor can improve methane production more than 30%. Nevertheless, cultivation......Ammonia is the most common inhibitor of anaerobic digestion (AD) process, resulting in suboptimal exploitation of the biogas potential of the feedstocks, causing significant economic losses to the biogas plants. Ammonia is mainly inhibiting the aceticlastic methanogens, while the hydrogenotrophic...... 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...

  20. The Surgical Scrub. Instructor's Packet. Learning Activity Package.

    Science.gov (United States)

    Runge, Lillian

    This instructor's packet accompanies the learning activity package (LAP) on the surgical scrub. Contents included in the packet are a time sheet, suggested uses for the LAP, an instruction sheet, final LAP reviews, a final LAP review answer key, a student performance checklist, suggested activities, an additional resources list, and student…

  1. DISTRIBUTION OF ESCHAR IN CHILDREN WITH SCRUB TYPHUS

    OpenAIRE

    Bahubali D; Natarajan; Hiremath

    2015-01-01

    Scrub typhus is caused by an intracellular bacterium, Orientia tsutsugamushi. It causes a disseminated vasculitic and perivascular inflammatory lesions. These lead to significant vascular leakage and end ‑ organ injury. Eschar is the site of inoculation. It is painless and non - pruritic. It is a useful indicator of the disease. We studied...

  2. Scrub Typhus in the Republic of Palau, Micronesia

    OpenAIRE

    Durand, A. Mark; Kuartei, Stevenson; Togamae, Ishmael; Sengebau, Maireng; Demma, Linda; Nicholson, William; O'Leary, Michael

    2004-01-01

    In October 2001, an outbreak of febrile illness began in the southwest islands group of the Republic of Palau. Through October 2003, a total of 15 southwest islanders experienced fever >39.5°C and abdominal distress, both lasting >7days. Orientia tsutsugamushi, the agent of scrub typhus, was subsequently identified as the cause.

  3. MAGNESIA SCRUBBING APPLIED TO A COAL-FIRED POWER PLANT

    Science.gov (United States)

    The report gives results of a full-size demonstration of the magnesia wet-scrubbing system for flue gas desulfurization (FGD) on a coal-fired utility boiler. The system was designed to desulfurize half the flue gas from a 190-MW rated capacity generating unit firing 3.5% sulfur c...

  4. Simultaneous stack-gas scrubbing and waste water treatment

    Science.gov (United States)

    Poradek, J. C.; Collins, D. D.

    1980-01-01

    Simultaneous treatment of wastewater and S02-laden stack gas make both treatments more efficient and economical. According to results of preliminary tests, solution generated by stack gas scrubbing cycle reduces bacterial content of wastewater. Both processess benefit by sharing concentrations of iron.

  5. Mitigate emissions of Ammonia from Nitrogen fertilizers

    International Nuclear Information System (INIS)

    Ammonia emissions are one of the main causes of acidification and eutrophication processes, and one of the most important contributors to the formation of secondary PM. The European NEC Directive 2001/81/CE introduced compulsory national emission ceiling for different pollutants and fixed for each countries a national ceiling for ammonia emissions to be reached in 2010. Agriculture plays a crucial role by emitting more than 90% of the total ammonia emissions. The main sources are livestock and fertilizer uses. In our activities we have studied the effects of different strategies to reduce Nitrogen fertilizer use and specifically Urea in Italy at the year 2010 and 2020. Different measures and techniques have been evaluated to estimate their effects as a potential options to mitigate emissions: fertilization, controlled release of fertilizers and biological agriculture. Each one of this option has been evaluated in terms of NH3 emission abatement showing that they could together provide good result in reducing ammonia air emission

  6. Synthesis of Scrub-Oak Ecosystem Responses to Elevated CO2

    Energy Technology Data Exchange (ETDEWEB)

    Hungate, Bruce

    2014-11-07

    This report summarizes a synthesis project of a long-term global change experiment conducted at the Kennedy Space Center, Florida, investigating how increasing concentrations of atmospheric carbon dioxide (CO2) influences the functioning of a fire-dominated scrub-oak ecosystem. The experiment began in 1996 and ended in 2007. Results presented here summarize the effects of elevated CO2 on plant growth, soil processes, carbon and nutrient cycling, and other responses. Products include archived data from the experiment, as well as six publications in the peer-reviewed literature.

  7. 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%。

  8. 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)

  9. 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.

  10. 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

  11. Release of ammonia from HAN-type PHA

    International Nuclear Information System (INIS)

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

  12. Recovery of oxalate from scrubbing solution containing rare earths and iron produced during uranium recovery from phosphoric acid

    International Nuclear Information System (INIS)

    In this paper a method has been described to recover oxalate from oxalic acid containing iron. The process involves the adjusting the pH of the solution, adding calcium chloride 100% excess than stoichiometric amount and digesting the slurry for 2 hours followed by filtration. The calcium oxalate is decomposed with sulphuric acid to obtain gypsum and oxalic acid. The acid is recycled for scrubbing of iron

  13. 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...... Regulation (EC) No 1565/2000. The present Flavouring Group Evaluation deals with ammonia [FL-no: 16.009], and three ammonia salts (diammonium sulphide [FL-no: 16.002], ammonium chloride [FL-no: 16.048] and ammonium hydrogen sulphide [FL-no: 16.059]). The flavouring substances cannot exist as geometrical or...... a wide range of food items up to very high amounts. Hydrogen sulphide is also reported to occur naturally in a wide range of food items. In its evaluation, the Panel as a default used the “Maximised Survey-derived Daily Intake” (MSDI) approach to estimate the per capita intakes of the flavouring...

  14. 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。

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

    Science.gov (United States)

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

  16. 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.

  17. 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.

  18. The effect of silver impregnation of surgical scrub suits on surface bacterial contamination.

    Science.gov (United States)

    Freeman, A I; Halladay, L J; Cripps, P

    2012-06-01

    Silver-impregnated fabrics are widely used for their antibacterial and antifungal effects, including for clinical clothing such as surgical scrub suits (scrubs). This study investigated whether silver impregnation reduces surface bacterial contamination of surgical scrubs during use in a veterinary hospital. Using agar contact plates, abdominal and lumbar areas of silver-impregnated nylon or polyester/cotton scrubs were sampled for surface bacterial contamination before (0 h) and after 4 and 8h of use. The number of bacterial colonies on each contact plate was counted after 24 and 48 h incubation at 37°C. Standard basic descriptive statistics and mixed-effects linear regression were used to investigate the association of possible predictors of the level of bacterial contamination of the scrubs with surface bacterial counts. Silver-impregnated scrubs had significantly lowered bacterial colony counts (BCC) at 0 h compared with polyester/cotton scrubs. However, after 4 and 8h of wear, silver impregnation had no effect on BCC. Scrub tops with higher BCC at 0 h had significantly higher BCC at 4 and 8h, suggesting that contamination present at 0 h persisted during wear. Sampling from the lumbar area was associated with lower BCC at all three time points. Other factors (contamination of the scrub top with a medication/drug, restraint of patients, working in the anaesthesia recovery area) also affected BCC at some time points. Silver impregnation appeared to be ineffective in reducing bacterial contamination of scrubs during use in a veterinary hospital. PMID:22015140

  19. Colour coding scrubs as a means of improving perioperative communication.

    Science.gov (United States)

    Litak, Dominika

    2011-05-01

    Effective communication within the operating department is essential for achieving patient safety. A large part of the perioperative communication is non-verbal. One type of non-verbal communication is 'object communication', the most common form of which is clothing. The colour coding of clothing such as scrubs has the potential to optimise perioperative communication with the patients and between the staff. A colour contains a coded message, and is a visual cue for an immediate identification of personnel. This is of key importance in the perioperative environment. The idea of colour coded scrubs in the perioperative setting has not been much explored to date and, given the potential contributiontowards improvement of patient outcomes, deserves consideration. PMID:21834289

  20. Electron Cloud and Scrubbing Studies for the SPS in 2012

    CERN Document Server

    Bartosik, H; Rumolo, G; Caspers, F; Driss Mensi, M; Federmann, S; Holz, M; Neupert, H; Taborelli, M

    2013-01-01

    It is important to collect all the relevant information to qualify the present status of the electron cloud in the SPS before the Long Shutdown (LS1). Therefore several electron cloud studies have taken place in the SPS during the 2012 run. At the beginning of the running period, five days were fully dedicated to electron cloud activities and scrubbing studies. After that, a few more MD sessions were devoted to following up on the studies started in the scrubbing week. These results, in combination with detailed simulation studies, will provide the basis for defining strategies of electron cloud mitigation as required for the production of future high intensity and high brightness beams within the LHC Injectors Upgrade (LIU) project.

  1. Phenological patterns in Mediterranean pastures and scrubs of Catalonia

    OpenAIRE

    Guàrdia i Rúbies, Roser; Casas i Arcarons, M. Carme (Maria Carme); Ninot i Sugrañes, Josep Maria

    1998-01-01

    On the basis of two parallel data sets refering to phenological events in open scrubs and pastures at two sites (Balaguer and Vic), the authors present a comprehensive report of the phenology of these Mediterranean communities. Four main phenophases (vegetative growth, flowering, fruiting and resting) were recorded monthly in 11 communities over 15 months. The results allow comparisons to be drawn between localities and communities, both at community and species levels, and to consider the ef...

  2. Severe scrub typhus infection: Clinical features, diagnostic challenges and management.

    Science.gov (United States)

    Peter, John Victor; Sudarsan, Thomas I; Prakash, John Anthony J; Varghese, George M

    2015-08-01

    Scrub typhus infection is an important cause of acute undifferentiated fever in South East Asia. The clinical picture is characterized by sudden onset fever with chills and non-specific symptoms that include headache, myalgia, sweating and vomiting. The presence of an eschar, in about half the patients with proven scrub typhus infection and usually seen in the axilla, groin or inguinal region, is characteristic of scrub typhus. Common laboratory findings are elevated liver transaminases, thrombocytopenia and leukocytosis. About a third of patients admitted to hospital with scrub typhus infection have evidence of organ dysfunction that may include respiratory failure, circulatory shock, mild renal or hepatic dysfunction, central nervous system involvement or hematological abnormalities. Since the symptoms and signs are non-specific and resemble other tropical infections like malaria, enteric fever, dengue or leptospirosis, appropriate laboratory tests are necessary to confirm diagnosis. Serological assays are the mainstay of diagnosis as they are easy to perform; the reference test is the indirect immunofluorescence assay (IFA) for the detection of IgM antibodies. However in clinical practice, the enzyme-linked immuno-sorbent assay is done due to the ease of performing this test and a good sensitivity and sensitivity when compared with the IFA. Paired samples, obtained at least two weeks apart, demonstrating a ≥ 4 fold rise in titre, is necessary for confirmation of serologic diagnosis. The mainstay of treatment is the tetracycline group of antibiotics or chloramphenicol although macrolides are used alternatively. In mild cases, recovery is complete. In severe cases with multi-organ failure, mortality may be as high as 24%. PMID:26261776

  3. Dry-Scrubbing of Acid Gases in Recirculating Cyclones

    OpenAIRE

    Chibante, Vania; Fonseca, Ana; Salcedo, Romualdo

    2007-01-01

    This paper describes a laboratory-scale study on the use of recirculating cyclones as reaction chambers for dry scrubbing of gaseous HCl with solid slaked lime particles. This gas cleaning system combines a numerically optimized reverse flow gas cyclone (RS_VHE geometry) with a straight-through cyclone concentrator, which simultaneously increases the capture of the solid particles and promotes their partial recirculation. A laboratory-scale study was undertaken to test this technology and to ...

  4. 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

  5. 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.

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

    DEFF Research Database (Denmark)

    Fotidis, Ioannis; Wang, Han; Fiedel, Nicolai Russell;

    2014-01-01

    Ammonia-rich substrates inhibit anaerobic digestion (AD) process and constitute the main reason of 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...... 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....

  7. POSSIBILITY OF BENEFICIATION OF SILICA SAND FROM THE CROATIAN DEPOSITS USING ATTRITION SCRUBBING

    Directory of Open Access Journals (Sweden)

    Ivan Sobota

    2011-12-01

    Full Text Available To meet high quality requirements defined for specific industrial applications, the raw sand often has to be subjected to extensive physical and chemical processing. The possibility of achieving silica sand concentrate of required quality depends mostly on raw sand properties, primarily mineral impurity types and contents, and features of applied beneficiation methods. When the impurities occur in the form of oxide coatings on the surfaces of the single sand grains, attriton scrubbing is applied. By reducing the proportion of oxide coatings on the grains, the quality of sand can be improved. With the aim to determine the possibilities of the beneficiation of silica sand from significant Croatian deposits (“Vrtlinska”, “Štefanac” and “Španovica” and achieve concentrate grade complying with the requirements of domestic industry, laboratory tests were conducted on three raw sand samples with different SiO2 and impurity contents. Grain size distribution, chemical and mineral composition of raw sand samples, and the possibility of their quality improvement by applying the washing, classification and attrition scrubbing were defined by analysis of test results (the paper is published in Croatian.

  8. Clinical indicators for severe prognosis of scrub typhus

    Directory of Open Access Journals (Sweden)

    Sriwongpan P

    2013-10-01

    Full Text Available Pamornsri Sriwongpan,1,2 Pornsuda Krittigamas,3 Pacharee Kantipong,4 Naowarat Kunyanone,5 Jayanton Patumanond,1 Sirianong Namwongprom1,61Clinical Epidemiology Program, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; 2Department of Social Medicine, Chiang Rai Prachanukroh Hospital, Chiang Rai, Thailand; 3Department of General Pediatrics, Nakornping Hospital, Chiang Mai, Thailand; 4Department of Internal Medicine, 5Department of Medical Technology, Chiang Rai Prachanukroh Hospital, Chiang Rai, Thailand; 6Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, ThailandBackground: The study explored clinical risk characteristics that may be used to forecast scrub typhus severity under routine clinical practices.Methods: Retrospective data were collected from patients registered at two university-affiliated tertiary care hospitals in the north of Thailand, from 2004 to 2010. Key information was retrieved from in-patient records, out patient cards, laboratory reports and registers. Patients were classified into three severity groups: nonsevere, severe (those with at least one organ involvement, and deceased. Prognostic characteristics for scrub typhus severity were analyzed by a multivariable ordinal continuation ratio regression.Results: A total of 526 patients were classified into nonsevere (n = 357, severe (n = 100, and deceased (n = 69. The significant multivariable prognostic characteristics for scrub typhus severity were increased body temperature (odds ratio [OR] = 0.58, 95% confidence interval [CI] = 0.45–0.74, P < 0.001, increased pulse rate (OR = 1.03, 95% CI = 1.01–1.05, P < 0.001, presence of crepitation (OR = 3.25, 95% CI = 1.52–6.96, P = 0.001, increased percentage of lymphocytes (OR = 0.97, 95% CI = 0.95–0.98, P = 0.001, increased aspartate aminotransferase (every 10 IU/L (OR = 1.04, 95% CI = 1.02–1.06, P < 0.001, increased serum albumin (OR = 0.47, 95% CI = 0.27–0.80, P = 0

  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. 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

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

    Science.gov (United States)

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

    2003-01-15

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

  12. Vehicular Quality Biomethane Production from Biogas by Using an Automated Water Scrubbing System

    OpenAIRE

    Chandra, R; Vijay, V. K.; Subbarao, P. M. V.

    2012-01-01

    This paper presents the results of an automated water scrubbing system used for enrichment of methane content in the biogas, to produce vehicular grade biomethane fuel. Incorporation of automatic control systems for precisely regulating the water level and maintaining constant operating pressure in the packed bed absorption column of water scrubbing system resulted in steady-state operation of the scrubbing system and a consistent supply of methane-enriched biogas from the gas outlet. The imp...

  13. Role of Advanced MRI Brain Sequences in Diagnosing Neurological Complications of Scrub Typhus

    Directory of Open Access Journals (Sweden)

    Shikha Sood

    2015-01-01

    Full Text Available Scrub typhus is a rare disease affecting many organs and causing vasculitis by affecting the endothelium of blood vessels. Review of literature shows that there are only a few case reports describing the neuroradiological manifestations of scrub typhus. This case report describes how newer and advanced MRI sequences are able to diagnose neurological complications of scrub typhus, such as hemorrhages, meningoencephalitis, infarctions, cranial nerve involvement, thrombosis, and hypoperfusion, that are not picked up on routine magnetic resonance imaging (MRI sequences.

  14. Scrub typhus meningitis: An under-recognized cause of aseptic meningitis in India

    OpenAIRE

    Kundavaram Paul Prabhakar Abhilash; Karthik Gunasekaran; Shubhanker Mitra; Shalom Patole; Sowmya Sathyendra; Sudha Jasmine; G M Varghese

    2015-01-01

    Background: Central nervous system (CNS) involvement in scrub typhus is seen in up to a quarter of patients. However, the literature on cerebrospinal fluid (CSF) analysis and outcome in meningitis/meningo-encephalitis due to scrub typhus is scant. Materials and Methods: This retrospective study included patients who were admitted to a medical college hospital with scrub typhus meningitis/meningo-encephalitis between 2005 and 2011. The clinical and laboratory profile, details of CSF analys...

  15. First case of scrub typhus with meningoencephalitis from Kerala: An emerging infectious threat

    OpenAIRE

    2012-01-01

    Scrub typhus is a rickettsial disease caused by Orientia tsutsugamushi, one of the most common infectious diseases in the Asia-Pacific region. It has been reported from northern, eastern, and southern India, and its presence has been documented in at least 11 Indian states. However, scrub typhus meningoencephalitis has not been well documented in Kerala. We report two cases of scrub typhus meningoencephalitis from northern Kerala. The diagnosis was made based on the clinical pictures, presenc...

  16. Tsutsugamushi Disease (Scrub Typhus) Meningoencephalitis in North Eastern India: A Prospective Study

    OpenAIRE

    Sharma, SR; Masaraf, H; Lynrah, KG; Lyngdoh, M

    2015-01-01

    Background: Scrub typhus is rampant in northern, eastern, and southern India. Central nervous system involvement in the form of meningitis or meningoencephalitis is common in scrub typhus. As specific laboratory methods remain inadequate or inaccessible in developing countries, prompt diagnosis is often difficult. Aim: The aim of this study was to characterize neurological complications in scrub typhus from northeastern region of India. Subjects and Methods: We did a prospective study of scru...

  17. Scrub Typhus: Surveillance, Clinical Profile and Diagnostic Issues in Shandong, China

    OpenAIRE

    Zhang, Meng; Zhao, Zhong-Tang; Wang, Xian-Jun; Li, Zhong; Ding, Lei; Ding, Shu-Jun

    2012-01-01

    To elucidate the epidemic status, clinical profile, and current diagnostic issues of scrub typhus in Shandong Province, we analyzed the surveillance data of scrub typhus from 2006 to 2011 and conducted a hospital-based disease survey in 2010. Scrub typhus was clustered in mountainous and coastal areas in Shandong Province, with an epidemic period from September to November. The most common manifestations were fever (100%), eschar or skin ulcer (86.3%), fatigue (71.6%), anorexia (71.6%), and r...

  18. Surgical swab counting: a qualitative analysis from the perspective of the scrub nurse.

    Science.gov (United States)

    D'Lima, D; Sacks, M; Blackman, W; Benn, J

    2014-05-01

    The aim of the study was to conduct a qualitative exploration of the sociotechnical processes underlying retained surgical swabs, and to explore the fundamental reasons why the swab count procedure and related protocols fail in practice. Data was collected through a set of 27 semistructured qualitative interviews with scrub nurses from a large, multi-site teaching hospital. Interview transcripts were analysed using established constant comparative methods, moving between inductive and deductive reasoning. Key findings were associated with interprofessional perspectives, team processes and climate and responsibility for the swab count. The analysis of risk factors revealed that perceived social and interprofessional issues played a significant role in the reliability of measures to prevent retained swabs. This work highlights the human, psychological and organisational factors that impact upon the reliability of the process and gives rise to recommendations to address contextual factors and improve perioperative practice and training. PMID:24908834

  19. Ammonia in Archives.

    Czech Academy of Sciences Publication Activity Database

    Mašková, Ludmila

    -: -, 2016, s. 58-59. ISBN N. [Indoor Air Quality - in Heritage and Historic Environment s. Birmingham (GB), 03.03.2016-04.03.2016] R&D Projects: GA MK DF11P01OVV020 Keywords : ammonia * diffusive sampling * indoor source Subject RIV: CF - Physical ; Theoretical Chemistry

  20. Possibility of scrub typhus in fever of unknown origin (FUO cases: An experience from Rajasthan

    Directory of Open Access Journals (Sweden)

    R Bithu

    2014-01-01

    Full Text Available Purpose: Fever of unknown origin (FUO has multiple causes. Scrub typhus is less known cause of FUO in India. The present study reports a recent epidemic of scrub typhus amongst cases of FUO from different areas of Rajasthan, India. There was high mortality in undiagnosed cases of FUO which lead to the diagnosis of scrub typhus. Objective: To study the possibility of scrub typhus as a causative factor in FUO cases by qualitative detection of IgM antibodies with ELISA. Materials and Methods: From September 2012 to December 2012, 271 serum samples of FUO cases were analysed for IgM antibodies to Orientia tsutsugamushi along with dengue, malaria, typhoid, tuberculosis and brucellosis. Results: Scrub typhus IgM antibodies by ELISA were detected in 133 (49.1% patients. Scrub typhus positivity was significantly higher among female in comparison to males (P < 0.05. Maximum positivity of scrub typhus was found in females of 46-60 years age group. The laboratory parameters were abnormal in most of the patients as evident by thrombocytopenia (63%, deranged liver functions (56% and renal functions (25%. Conclusion: The present study emphasises the importance of scrub typhus among cases of FUO especially after rainy season and during early cooler months. The study also highlights the significance of ELISA method for rapid and early reporting and ruling out scrub typhus in FUO cases.

  1. Enrichment of high ammonia tolerant methanogenic culture

    DEFF Research Database (Denmark)

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

    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...... 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...

  2. CLEAR LIQUOR SCRUBBING WITH ANHYDRITE PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    R.C. SKARUPA; T.R. CAREY

    1998-08-01

    This project is funded by the US Department of Energy's Federal Energy Technology Center (DOE/FETC) under a cost-sharing PRDA with Radian International. The Electric Power Research Institute (EPRI) is providing co-funding and technical oversight. The project is part of FETC's Advanced Power Systems Program, whose mission is to accelerate the commercialization of affordable, high-efficiency, low emission, coal-fueled electric generating technologies. This project was submitted in response to Area 4 of DOE's Mega-PRDA: Advanced High-Performance SO{sub 2} Control Concepts. The goals of this research area are to develop advanced flue gas desulfurization (FGD) processes that achieve greater than 99% SO{sub 2} removal efficiency, are 25% cheaper than commercial FGD systems, and provide a valuable byproduct that will be recycled rather than disposed. Area 4 also included the development of a byproduct process that could be added to FGD systems to produce high value byproducts for reuse rather than disposal.

  3. Modeling dry-scrubbing of gaseous HCl with hydrated lime in cyclones with and without recirculation.

    Science.gov (United States)

    Chibante, Vania G; Fonseca, Ana M; Salcedo, Romualdo R

    2010-06-15

    A mathematical model describing the dry-scrubbing of gaseous hydrogen chloride (HCl) with solid hydrated lime particles (Ca(OH)(2)) was developed and experimentally verified. The model applies to cyclone systems with and without recirculation, where reaction and particle collection occurs in the same processing unit. The Modified Grain Model was selected to describe the behavior of the reaction process and it was assumed that the gas and the solid particles flow in the reactor with a plug flow. In this work, this behavior is approximated by a cascade of N CSTRs in series. Some of the model parameters were estimated by optimization taking into account the experimental results obtained. A good agreement was observed between the experimental results and those predicted by the model, where the main control resistance is the diffusion of the gaseous reactant in the layer of solid product formed. PMID:20185231

  4. AFM, XPS and RBS studies of the growth process of CdS thin films on ITO/glass substrates deposited using an ammonia-free chemical process

    International Nuclear Information System (INIS)

    This paper deals with a detailed study of the growth stages of CdS thin films on ITO/glass substrates by chemical bath deposition (CBD). The chemical and morphological characterization was done through X-ray photoelectron spectroscopy (XPS), Rutherford backscattering spectrometry (RBS), and atomic force microscopy (AFM) techniques. On the other hand, optical transmission and X-ray diffraction (XRD) measurements were performed in order to study the optical and structural properties of the films. The time, the chemistry, and morphology of the different stages that form the growth process by CBD were identified through these results. Furthermore, clear evidence was obtained of the formation of Cd(OH)2 as the first chemical species adhered to the substrate surface which forms the first nucleation centers for a good CdS formation and growth. On the other hand, the ITO coating caused growth stages to occur earlier than in just glass substrates, with which we can obtain a determined thickness in a shorter deposition time. We were able to prove that CBD is a good technique for the manufacture of thin films of semiconductor materials, since the CdS film does not have any impurities. Completely formed films were transparent, uniform, with good adherence to the substrate, of a polycrystalline nature with a hexagonal structure. These results indicate that films obtained by CBD are good candidates to be applied in different optoelectronic devices.

  5. Sugar-Driven Prebiotic Synthesis of Ammonia from Nitrite

    Science.gov (United States)

    Weber, Arthur L.

    2010-03-01

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

  6. Pool scrubbing and hydrodynamic experiments on jet injection regime

    International Nuclear Information System (INIS)

    Plant analyses have shown that pool scrubbing can play an important role in source term during PWR risk dominant sequences. An examination ofboundary conditions governing fission products and aerosols transport through aqueous beds revealed that most of radioactivity is discharged into the pool under jet injection regime. This fact and the lack of experimental data under such conditions pointed the need of setting out an experimental programme which provided reliable experimental data to validate code models. In this report the major results of a pool scrubbing experimental programme carried out in PECA facility are presented. One of the major findings was that a remarkable fraction of particle absorption was not a function of the residence time of bubbles rising through the pool. Such a contribution was assumed to be associated to aerosol removal mechanisms acting at the pool entrance. As a consequence, a hydrodynamic experimental plan was launched to examine the gas behaviour during the initial stages in the pool. Size and shape of gas nuclei the pool were measured and fitted to a long normal distribution. Particularly, size was found to be quite sensitive to inletgas flow and at minor extent to gas composition and pool temperature. SPARC90 and BUSCA-AUG92 were used to simulate the retention tests. Whereas SPARC90 showed a pretty good agreement with experimental data, BUSCA-AUG92 results were far away from measurements in all the cases. SPARC90consistency apparently pointed out the important role of fission products and aerosols retention at the injection zone; nonetheless, a peer examination of pool scrubbing phenomenology at the pool entrance should be carried out to test both hydrodynamic and removal models. Hence, one of the major highlights drawn from this work was the need of further research under representative severe accident conditions (i.e., saturated pools, jet injection regimes, etc.), as well as separate effect tests to validate, improve and

  7. Self-Scrubbing Coal -- an integrated approach to clean air

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, K.E. [Custom Coals Corp., Pittsburgh, PA (United States)

    1997-12-31

    Carefree Coal is coal cleaned in a proprietary dense-media cyclone circuit, using ultrafine magnetite slurries, to remove noncombustible material, including up to 90% of the pyritic sulfur. Deep cleaning alone, however, cannot produce a compliance fuel from coals with high organic sulfur contents. In these cases, Self-Scrubbing Coal will be produced. Self-Scrubbing Coal is produced in the same manner as Carefree Coal except that the finest fraction of product from the cleaning circuit is mixed with limestone-based additives and briquetted. The reduced ash content of the deeply-cleaned coal will permit the addition of relatively large amounts of sorbent without exceeding boiler ash specifications or overloading electrostatic precipitators. This additive reacts with sulfur dioxide (SO{sub 2}) during combustion of the coal to remove most of the remaining sulfur. Overall, sulfur reductions in the range of 80--90% are achieved. After nearly 5 years of research and development of a proprietary coal cleaning technology coupled with pilot-scale validation studies of this technology and pilot-scale combustion testing of Self-Scrubbing Coal, Custom Coals Corporation organized a team of experts to prepare a proposal in response to DOE`s Round IV Program Opportunity Notice for its Clean Coal Technology Program under Public Law 101-121 and Public Law 101-512. The main objective of the demonstration project is the production of a coal fuel that will result in up to 90% reduction in sulfur emissions from coal-fired boilers at a cost competitive advantage over other technologies designed to accomplish the same sulfur emissions and over naturally occurring low sulfur coals.

  8. Sol-gel process for preparation of YBa2Cu4O8 from acidic acetates/ammonia/ascorbic acid systems

    International Nuclear Information System (INIS)

    YBa2Cu4Ox sols were prepared by addition of ammonia to acidic acetate solutions of Y3+, Ba2+, and Cu2+. Ascorbic acid was added to part of the sol. The resultant sols were gelled to a shard or a coating by evaporation at 60 C. Addition of ethanol to the sols facilitated formation of gel coatings, fabricated by a dipping technique, on Ag or glass or substrates. At 100 C, gels formed in the presence of ascorbic acid were perfectly amorphous, in contrast to crystalline acetate gels. The quality of coatings prepared from ascorbate gels was superior to that of acetate gel coatings

  9. New English words in Scrubs and their Finnish translations

    OpenAIRE

    Karvonen, Kati

    2011-01-01

    Tutkielman tarkoituksena on selvittää amerikkalaisessa komediasarjassa Tuho-osastossa (engl. Scrubs) esiintyvien uusien englanninkielisten sanojen syntytapoja ja näiden sanojen suomenkielisiä käännöksiä. Tutkimuksessa keskitytään seitsemään erilaiseen sananmuodostustekniikkaan, sekä tekstitysten kääntämiseen. Niinpä tutkimuskysymys on kaksiosainen: 1. Minkä tyyppisiä sananmuodostustekniikoita käytetään uusien englanninkielisten sanojen luomisessa Tuho-osastossa, ja 2. Kuinka nämä uudet sanat ...

  10. Scrub typhus:pathophysiology, clinical manifestations and prognosis

    Institute of Scientific and Technical Information of China (English)

    Senaka Rajapakse; Chaturaka Rodrigo; Deepika Fernando

    2012-01-01

    ABSTRACT Scrub typhus is a zoonosis caused by the pathogenOrientia tsutsugamushi (O. tsutsugamushi). The disease has significant prevalence in eastern and Southeast Asia. Usually presenting as an acute febrile illness, the diagnosis is often missed because of similarities with other tropical febrile infections. Many unusual manifestations are present, and these are described in this review, together with an outline of current knowledge of pathophysiology. Awareness of these unusual clinical manifestations will help the clinician to arrive at an early diagnosis, resulting in early administration of appropriate antibiotics. Prognostic indicators for severe disease have not yet been clearly established.

  11. Imaging of Scrub Typhus by PET/CT.

    Science.gov (United States)

    Lv, Jing; Liu, Shuai; Pan, Yu; Ju, Huijun; Zhang, Yifan

    2015-10-01

    A 19-year-old man had an unexplained fever, dizziness, headache, fatigue, and pain in the scrotum. An FDG PET/CT imaging was acquired to assess fever of unknown origin. The images showed multiple foci of increased FDG activity in the enlarged lymph nodes in the body. In addition, mildly increased activity in the enlarged spleen and lung bases was also noted. The patient was eventually diagnosed with scrub typhus based on positive results of the Weil-Felix agglutination test, eschar in the scrotum, and effective therapy. PMID:26252322

  12. Gulf-Wide Information System, Environmental Sensitivity Index Scrub-Shrub and Wetlands, Geographic NAD83, LDWF (2001) [esi_scrub-shrub_wetland_LDWF_2001

    Data.gov (United States)

    Louisiana Geographic Information Center — This data set contains Environmental Sensitivity Index (ESI) scrub-shrub and wetlands data of coastal Louisiana. The ESI is a classification and ranking system,...

  13. A randomized crossover trial to decrease bacterial contamination on hospital scrubs.

    Science.gov (United States)

    Boutin, Mallory A; Thom, Kerri A; Zhan, Min; Johnson, J Kristie

    2014-11-01

    Healthcare worker attire may become contaminated with pathogenic organisms during a normal shift. We performed a randomized crossover study to assess whether treatment with an antimicrobial coating would decrease bacterial contamination on scrubs. Thirty percent of all scrubs were contaminated; there was no difference in the rate of contamination between the intervention and control groups. PMID:25333437

  14. A randomized-crossover trial to decrease bacterial contamination on hospital scrubs

    OpenAIRE

    Boutin, Mallory A.; Thom, Kerri A.; Zhan, Min; Johnson, J. Kristie

    2014-01-01

    Healthcare worker attire may become contaminated with pathogenic organisms during a normal shift. We performed a randomized-crossover study to assess whether treatment with an antimicrobial coating would decrease bacterial contamination on scrubs. Thirty percent of all scrubs were contaminated; there was no difference in the rate of contamination between intervention/control.

  15. A Spatiotemporal Database to Track Human Scrub Typhus Using the VectorMap Application.

    Directory of Open Access Journals (Sweden)

    Daryl J Kelly

    2015-12-01

    Full Text Available Scrub typhus is a potentially fatal mite-borne febrile illness, primarily of the Asia-Pacific Rim. With an endemic area greater than 13 million km2 and millions of people at risk, scrub typhus remains an underreported, often misdiagnosed febrile illness. A comprehensive, updatable map of the true distribution of cases has been lacking, and therefore the true risk of disease within the very large endemic area remains unknown. The purpose of this study was to establish a database and map to track human scrub typhus. An online search using PubMed and the United States Armed Forces Pest Management Board Literature Retrieval System was performed to identify articles describing human scrub typhus cases both within and outside the traditionally accepted endemic regions. Using World Health Organization guidelines, stringent criteria were used to establish diagnoses for inclusion in the database. The preliminary screening of 181 scrub typhus publications yielded 145 publications that met the case criterion, 267 case records, and 13 serosurvey records that could be georeferenced, describing 13,739 probable or confirmed human cases in 28 countries. A map service has been established within VectorMap (www.vectormap.org to explore the role that relative location of vectors, hosts, and the pathogen play in the transmission of mite-borne scrub typhus. The online display of scrub typhus cases in VectorMap illustrates their presence and provides an up-to-date geographic distribution of proven scrub typhus cases.

  16. 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

  17. 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...... 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/L) and...... free ammonia levels (Mesophilic: 3.31, 38.2, 63.68 and 89.15 g NH3-N/L. Thermophilic: 8.48, 97.82, 163.03 and 228.24 g NH3-N/L). The results indicated that both T. acetatoxydans and T. phaeum were more sensitive to high ammonia levels compared to the hydrogenotrophic methanogens tested. Additionally...

  18. 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.

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

    Directory of Open Access Journals (Sweden)

    Abd Rahman Mohd Yusri

    2011-01-01

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

  20. Volatile organic compounds treatment by compact chemical scrubbing:scrubbing solution recycling by advanced oxidation O3/H2O2.

    OpenAIRE

    Biard, Pierre-François; Couvert, Annabelle; Renner, Christophe; Levasseur, Jean-Pierre

    2011-01-01

    National audience This study focuses on Volatile Organic Compounds (VOC) treatment in a compact chemical scrubber composed of a structured packing operating at co-current and high gas superficial velocity (> 10 m.s-1). The scrubbing liquid is composed of ozone and hydrogen peroxide to generate very reactive hydroxyl radicals. Results demonstrate a high mineralisation rate of the transferred VOC, even with low oxidant concentrations. Therefore, the scrubbing liquid can be recycled and recir...

  1. Brushes and picks used on nails during the surgical scrub to reduce bacteria: a randomised trial.

    Science.gov (United States)

    Tanner, J; Khan, D; Walsh, S; Chernova, J; Lamont, S; Laurent, T

    2009-03-01

    Though brushes are no longer used on the hands and forearms during the surgical scrub, they are still widely used on the nails. The aim of this study was to determine whether nail picks and nail brushes are effective in providing additional decontamination during a surgical hand scrub. A total of 164 operating department staff were randomised to undertake one of the following three surgical hand-scrub protocols: chlorhexidine only; chlorhexidine and a nail pick; or chlorhexidine and a nail brush. Bacterial hand sampling was conducted before and 1h after scrubbing using a modified version of the glove juice method. No statistically significant differences in bacterial numbers were found between any two of the three intervention groups. Nail brushes and nail picks used during surgical hand scrubs do not decrease bacterial numbers and are unnecessary. PMID:19162371

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

    Science.gov (United States)

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

    2014-08-01

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

  3. Systematic randomised sampling along three landscape transects in the Netherlands reveals the geographically structured variation in Rubus scrubs

    NARCIS (Netherlands)

    Haveman, R.; Ronde, de I.; Bijlsma, R.J.; Schaminee, J.H.J.

    2014-01-01

    Rubus scrubs belong to the least known and understood vegetation types in Europe. At least in part this is due to the complicated taxonomy and species richness of the main genus in these scrubs. In this study, we explored the regional diversity of Rubus scrubs in the Netherlands. In order to get a c

  4. Sol-gel process for preparing YBa2Cu4O8 precursors from Y, Ba, and Cu acidic acetates/ammonia/ascorbic acid systems

    International Nuclear Information System (INIS)

    Sols were prepared by addition of ammonia to acidic acetate solutions of Y3+, Ba2+, and Cu2+. Ascorbic acid was added to a part of the sol. The resultant sols were gelled to a shard, a film, or microspheres by evaporation at 60 C or by extraction of water from drops of emulsion suspended in 2-ethylhexanol-1. Addition of ethanol to the sols facilitated the formation of gel films, fabricated by a dipping technique, on glass or silver substrates. At 100 C, gels that were formed in the presence of ascorbic acid were perfectly amorphous, in contrast to the crystalline acetate gels. Conversion of the amorphous ascorbate gels to final products was easier than for the acetate gels. The quality of coatings prepared from ascorbate gels was superior to that of acetate gel coatings

  5. 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.

  6. Pool scrubbing and hydrodynamic experiment on jet injection regime

    International Nuclear Information System (INIS)

    Plant analyses nave shown that pool scrubbing can play an important role in source term during PWR risk dominant sequences. An examination of boundary conditions governing fission products and aerosols transport through aqueous beds revealed that most of radioactivity is discharged into the pool under jet injection regime. This fact and the lack of experimental data under such conditions pointed the need of setting out an experimental programme which provided reliable experimental data to validate code models. In this report the major results of a pool scrubbing experimental programme carried out in PECA facility are presented. One of the major findings was that a remarkable fraction of particle absorption was not a function of the residence time of bubbles rising through the pool. Such a contribution was assumed to be associated to aerosol removal mechanism acting at the pool entrance. As a consequence. a hydrodynamic experimental plan was launched to examine the gas behaviour during the initial stages in the pool. Size and shape of gas nuclei in the pool were measured and fitted to a lognormal distribution. Particularly, size was found to be quite sensitive to inlet gas flow and at minor extent to gas composition and pool temperature. SPARC90 and BUSCA-AUG92 were used to simulate the retention tests. Whereas SPARC90 showed a pretty good agreement with experimental data, BUSCA-AUG92 results were far away from measurements in all the cases. SPARC90 consistency apparently pointed out the important role of fission products and aerosols retention at the injection zone; nonetheless, a peer examination of pool scrubbing phenomenology at the pool entrance should be carried out to test both hydrodynamic and removal models. Hence, one of the major high lights drawn from this work was the need of further research under representative severe accident conditions (i.e., saturated pools, jet injection regimes, etc.), as well as separate effect tests to validate, improve and

  7. Pool scrubbing and hydrodynamic experiment on jet injection regime

    Energy Technology Data Exchange (ETDEWEB)

    Peyres, V.; Espigares, M.M.; Polo, J.; Escudero, M.J.; Herranz, L.E.; Lopez, J.

    1995-07-01

    Plant analyses nave shown that pool scrubbing can play an important role in source term during PWR risk dominant sequences. An examination of boundary conditions governing fission products and aerosols transport through aqueous beds revealed that most of radioactivity is discharged into the pool under jet injection regime. This fact and the lack of experimental data under such conditions pointed the need of setting out an experimental programme which provided reliable experimental data to validate code models. In this report the major results of a pool scrubbing experimental programme carried out in PECA facility are presented. One of the major findings was that a remarkable fraction of particle absorption was not a function of the residence time of bubbles rising through the pool. Such a contribution was assumed to be associated to aerosol removal mechanism acting at the pool entrance. As a consequence. a hydrodynamic experimental plan was launched to examine the gas behaviour during the initial stages in the pool. Size and shape of gas nuclei in the pool were measured and fitted to a lognormal distribution. Particularly, size was found to be quite sensitive to inlet gas flow and at minor extent to gas composition and pool temperature. SPARC90 and BUSCA-AUG92 were used to simulate the retention tests. Whereas SPARC90 showed a pretty good agreement with experimental data, BUSCA-AUG92 results were far away from measurements in all the cases. SPARC90 consistency apparently pointed out the important role of fission products and aerosols retention at the injection zone; nonetheless, a peer examination of pool scrubbing phenomenology at the pool entrance should be carried out to test both hydrodynamic and removal models. Hence, one of the major high lights drawn from this work was the need of further research under representative severe accident conditions (i.e., saturated pools, jet injection regimes, etc.), as well as separate effect tests to validate, improve and

  8. Limestone scrubbing for 2000 flue gas desulfurization system. Final report, October 1, 1993--April 1, 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-10-16

    As emission limits for sulfur dioxide from utility coal-fired boilers become lower due to increased regulation and environmental concern around the globe, power generating companies require increasingly cost-effective pollution control technology in order to maintain or reduce the cost of electricity to the end user. Limestone based wet flue gas desulfurization, or WFGD, is the preferred sulfur dioxide removal technology for utilities in the US and worldwide. This is a result of its extensive reference list, lower risks, and lower evaluated overall costs. For more than two decades ABB has supplied WFGD systems and currently has greater than 29,000 MWe of scrubbing capacity in operation. Given the industry`s ever-present need for lower costs, ABB funds a continuous research and development program focused on technology advancements that will reduce both capital and operating costs for its customers. As a result of this effort the LS-2 Concept WFGD System was developed through revolutionary design changes in every significant subprocess of conventional WFGD technology. To demonstrate the cumulative effects of all the individual advancements of the LS-2 Concept and to prove the process`s viability and cost-efficiency under representative US power plant conditions, the Limestone Scrubbing for 2000 project was initiated. This report is the final submittal to the Ohio Coal Development Office to document the results of this demonstrate project. The four-phase project execution, from the initial design and procurement through erection and extensive testing, proceeded as scheduled and on budget. The project resulted in a successful reference program that illustrates, in detail, the improved efficiencies and costs of the LS-2 advancements.

  9. Surgical scrubbing: can we clean up our carbon footprints by washing our hands?

    Science.gov (United States)

    Somner, J E A; Stone, N; Koukkoulli, A; Scott, K M; Field, A R; Zygmunt, J

    2008-11-01

    A growing scientific consensus states that the global climate is changing and that human activity is responsible for these changes. It folLows that each of us has a responsibility to look at how our own lives impact on the environment. This study aimed to investigate water use during surgical scrubbing. Two water delivery systems were assessed to see whether technological innovation can promote more 'environmentally friendly' scrubbing behaviour. At least 10 different individuals, comprising surgeons, assistants and scrub nurses, were observed at two sites. Twenty-five separate surgical scrubs were observed in each location and the length of time for which the tap was on recorded. The tap was on during surgical scrubbing for a mean of 2 min 23 s at Gartnavel General Hospital (maximum: 4 min 37 s; minimum: 49 s; SD: 55 s) and for a mean of 1 min 7 s at Stobhill Hospital (maximum: 2 min 25 s; minimum: 19 s; SD: 33 s). The mean 'tap on' time (in seconds) at Gartnavel was significantly greater than that at Stobhill [t(39.5)=Pscrub. Surgical scrubbing is a ubiquitous procedure performed daily in healthcare settings. A simple technological solution can reduce water and energy use by modifying hand-washing behaviour and thereby reduce the carbon footprint of surgical scrubbing. PMID:18701193

  10. 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...

  11. Effects of DDT on bird population of scrub forest

    Science.gov (United States)

    Robbins, C.S.; Stewart, R.E.

    1949-01-01

    An oil spray of DDT was applied at the rate of five pounds per acre to a 90-acre tract of 5-year-old scrub and sapling growth at Beltsville, Maryland. Bird population studies were carried on in a 30-acre plot at the center of the sprayed area, and in a 30-acre check area of the same habitat one-half mile away. Of the five commonest species in the sprayed area, the Maryland yellowthroat, prairie warbler, and house wren were reduced 80 per cent, and the red-eyed towhee was apparently reduced 35 per cent; while no appreciable change in the numbers of yellow-breasted chats was noted. The total decrease for the five commonest species, which represented 77 per cent of the original population, was 65 per cent.

  12. 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

  13. The Effects of Surgical Hand Scrubbing Protocols on Skin Integrity and Surgical Site Infection Rates: A Systematic Review.

    Science.gov (United States)

    Liu, Liang Qin; Mehigan, Sinead

    2016-05-01

    This systematic review aimed to critically appraise and synthesize updated evidence regarding the effect of surgical-scrub techniques on skin integrity and the incidence of surgical site infections. Databases searched include the Cumulative Index to Nursing and Allied Health Literature, MEDLINE, Embase, and Cochrane Central. Our review was limited to eight peer-reviewed, randomized controlled trials and two nonrandomized controlled trials published in English from 1990 to 2015. Comparison models included traditional hand scrubbing with chlorhexidine gluconate or povidone-iodine against alcohol-based hand rubbing, scrubbing with a brush versus without a brush, and detergent-based antiseptics alone versus antiseptics incorporating alcohol solutions. Evidence showed that hand rubbing techniques are as effective as traditional scrubbing and seem to be better tolerated. Hand rubbing appears to cause less skin damage than traditional scrub protocols, and scrub personnel tolerated brushless techniques better than scrubbing using a brush. PMID:27129749

  14. Ammonia caramels: specifications and analysis.

    Science.gov (United States)

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

    1985-01-01

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

  15. Differential laundering practices of white coats and scrubs among health care professionals.

    Science.gov (United States)

    Munoz-Price, L Silvia; Arheart, Kristopher L; Lubarsky, David A; Birnbach, David J

    2013-06-01

    The role played by health care worker's uniforms on the horizontal transmission of organisms within the hospital is still controversial. To determine the differential laundering practices in regards to white coats and scrubs, we surveyed physicians present at the 3 weekly academic conferences with largest attendance at our hospital (medicine, pediatrics, and anesthesiology). Out of 160 providers, white coats were washed every 12.4 ± 1.1 days and scrubs every 1.7 ± 0.1 days (mean ± standard error; P scrubs more frequently than house staff (1.0 vs 1.9 days, respectively, P = .018), and no differences were observed among specialties. PMID:23219673

  16. Suitable control choices: exploring the roles of clean air suits and scrub suits in infection control

    OpenAIRE

    Abreu, Maria José

    2014-01-01

    Experts in infection control are often asked about issues related to the use of scrubs and clean air suits in the operating room (OR). So far there is no clear explanation or mandatory obligation why the surgical team has to wear clean air suits or scrub suits in ORs and, more importantly, what the main differences are between these two types of clothing. There is a general perception that the two are equal or very similar. So, what are clean air suits and scrub ...

  17. 18F-FDG PET/CT Findings of Scrub Typhus.

    Science.gov (United States)

    Kim, Jahae; Kwon, Seong Young; Kang, Sae-Ryung; Cho, Sang-Geon; Song, Ho-Chun

    2015-10-01

    Scrub typhus is an acute infectious disease caused by Orienta tsutsugamushi, which is clinically manifested by fever, generalized lymphadenopathy, diffuse myalgia, headache, maculopapular rash, and eschars at the site of chigger feedings. Diagnosis of scrub typhus requires compatible clinical features, history of exposure, and result of selorogic testing. In recent years, F-FDG PET/CT is seen as having increasing potential for use in examination and management of patients with infectious or inflammatory disorders. This is a PET/CT case demonstrating scrub typhus in a patient without evidence of recurrence of thyroid papillary cancer. PMID:26098289

  18. Scrub Typhus Presenting with Bilateral Lateral Rectus Palsy in A Female.

    Science.gov (United States)

    Ete, Tony; Mishra, Jaya; Barman, Bhupen; Mondal, Sumantro; Sivam, Rondeep Kumar Nath

    2016-04-01

    Scrub typhus, a rickettsial disease is endemic in several parts of India usually presenting with acute symptoms. Fever, maculopapular rash, eschar, history of tick exposure and supportive diagnostic tests usually leads to diagnosis. Scrub typhus should be included in the differential diagnosis in occasions when a patient presents with fever with or without eschar and isolated cranial nerve palsy. Here we are reporting a case of Scrub typhus who presented with fever and altered sensorium of short duration, eschar formation and bilateral lateral rectus palsy. Patient was treated with doxycycline with complete reversal of neurodeficit. PMID:27190871

  19. First case of scrub typhus with meningoencephalitis from Kerala: An emerging infectious threat

    Directory of Open Access Journals (Sweden)

    K Saifudheen

    2012-01-01

    Full Text Available Scrub typhus is a rickettsial disease caused by Orientia tsutsugamushi, one of the most common infectious diseases in the Asia-Pacific region. It has been reported from northern, eastern, and southern India, and its presence has been documented in at least 11 Indian states. However, scrub typhus meningoencephalitis has not been well documented in Kerala. We report two cases of scrub typhus meningoencephalitis from northern Kerala. The diagnosis was made based on the clinical pictures, presence of eschar, and a positive Weil-Felix test with a titer of > 1:320. The first patient succumbed to illness due to respiratory failure and the second patient improved well.

  20. The production of ammonia by multiheme cytochromes C.

    Science.gov (United States)

    Simon, Jörg; Kroneck, Peter M H

    2014-01-01

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

  1. 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...

  2. Electrochemical Synthesis of Ammonia in Solid Electrolyte Cells

    OpenAIRE

    MichaelStoukides

    2014-01-01

    Developed in the early 1900s, the “Haber–Bosch” synthesis is the dominant NH3 synthesis process. Parallel to catalyst optimization, current research efforts are also focused on the investigation of new methods for ammonia synthesis, including the electrochemical synthesis with the use of solid electrolyte cells. Since the first report on Solid State Ammonia Synthesis (SSAS), more than 30 solid electrolyte materials were tested and at least 15 catalysts were used as working electrodes. Thus fa...

  3. Plasma source ion implantation of ammonia into electroplated chromium

    International Nuclear Information System (INIS)

    Ammonia gas (NH3) has been used as a nitrogen source for plasma source ion implantation processing of electroplated chromium. No evidence was found of increased hydrogen concentrations in the bulk material, implying that ammonia can be used without risking hydrogen embrittlement. The retained nitrogen dose of 2.1 x 1017 N-at/cm2 is sufficient to increase the surface hardness of electroplated Cr by 24% and decrease the wear rate by a factor of 4

  4. Nitrocarburising in ammonia-hydrocarbon gas mixtures

    DEFF Research Database (Denmark)

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

    The present work investigates the possibility of nitrocarburising in ammonia-acetylene-hydrogen and ammoniapropene- hydrogen gas mixtures, where unsaturated hydrocarbon gas is the carbon source during nitrocarburising. Consequently, nitrocarburising is carried out in a reducing atmosphere and...... microscopy and X-ray diffraction analysis. It is shown that the use of unsaturated hydrocarbon gas in nitrocarburising processes is a viable alternative to traditional nitrocarburising methods....

  5. 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.

  6. Effect of different ammonia concentrations on community succession of ammonia-oxidizing microorganisms in a simulated paddy soil column.

    Directory of Open Access Journals (Sweden)

    Hu Baolan

    Full Text Available Ammonia oxidation is performed by both ammonia-oxidizing bacteria (AOB and ammonia-oxidizing archaea (AOA. To explore the effect of ammonia concentration on the population dynamic changes of ammonia-oxidizing microorganisms, we examined changes in the abundance and community composition of AOA and AOB in different layers. Most of the archaeal amoA sequences were Nitrosotalea-related and the proportion that Nitrosotalea cluster occupied decreased in the surface layer and increased in the deep layer during the cultivation process. Nitrosopumilus-related sequences were only detected in the deep layer in the first stage and disappeared later. Both phylogenetic and quantitative analysis showed that there were increased Nitrosomonas-related sequences appeared in the surface layer where the ammonia concentration was the highest. Both AOA and AOB OTU numbers in different layers decreased under selective pressure and then recovered. The potential nitrification rates were 25.06 µg · N · L(-1 · g(-1 dry soil · h(-1 in the mid layer which was higher than the other two layers. In general, obvious population dynamic changes were found for both AOA and AOB under the selective pressure of exogenous ammonia and the changes were different in three layers of the soil column.

  7. 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)

  8. PROCEEDINGS: INDUSTRY BRIEFING ON EPA LIME/LIMESTONE WET SCRUBBING TEST PROGRAMS AUGUST 1978

    Science.gov (United States)

    The proceedings document presentations made during the August 29, 1978 industry briefing conference which dealt with the status of EPA/IERL-RTP's flue gas desulfurization (FGD) research, development, and application programs. Subjects considered included: lime/limestone scrubbing...

  9. Effect of Latitude and Seasonal Variation on Scrub Typhus, South Korea, 2001-2013.

    Science.gov (United States)

    Jeung, Ye Sul; Kim, Choon-Mee; Yun, Na Ra; Kim, Seok-Won; Han, Mi Ah; Kim, Dong-Min

    2016-01-01

    In South Korea, scrub typhus is one of the most common rickettsial diseases. The number of scrub typhus patients has increased in South Korea, a total of 69,210 cases were reported from 2001 to 2013. The seasonality and relation of scrub typhus cases to latitude were analyzed in this article using data obtained from the National Notifiable Diseases Surveillance System website of the Korea Centers for Disease Control and Prevention. The incidence of scrub typhus tended to increase in the later months of the year, especially in October-December. In general, lower latitudes were associated with a later peak incidence. Our results suggest for the first time that the monthly observed incidence tended to increase in the later months of the year as the latitude decreased, and on a yearly basis in Korea. PMID:26503283

  10. 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.

  11. Scrub-shrub bird habitat associations at multiple spatial scales in beaver meadows in Massachusetts

    Science.gov (United States)

    Chandler, R.B.; King, D.I.; DeStefano, S.

    2009-01-01

    Most scrub-shrub bird species are declining in the northeastern United States, and these declines are largely attributed to regional declines in habitat availability. American Beaver (Castor canadensis; hereafter "beaver") populations have been increasing in the Northeast in recent decades, and beavers create scrub-shrub habitat through their dam-building and foraging activities. Few systematic studies have been conducted on the value of beaver-modified habitats for scrub-shrub birds, and these data are important for understanding habitat selection of scrub-shrub birds as well as for assessing regional habitat availability for these species. We conducted surveys in 37 beaver meadows in a 2,800-km2 study area in western Massachusetts during 2005 and 2006 to determine the extent to which these beaver-modified habitats are used by scrub-shrub birds, as well as the characteristics of beaver meadows most closely related to bird use. We modeled bird abundance in relation to microhabitat-, patch-, and landscape-context variables while adjusting for survey-specific covariates affecting detectability using N-mixture models. We found that scrub-shrub birds of regional conservation concern occupied these sites and that birds responded differently to microhabitat, patch, and landscape characteristics of beaver meadows. Generally, scrub-shrub birds increased in abundance along a gradient of increasing vegetation complexity, and three species were positively related to patch size. We conclude that these habitats can potentially play an important role in regional conservation of scrub-shrub birds and recommend that conservation priority be given to larger beaver meadows with diverse vegetation structure and composition. ?? 2009 by The American Ornithologists' Union. All rights reserved.

  12. Diagnostic evaluation of rapid tests for scrub typhus in the Indian population is needed

    OpenAIRE

    Shivalli, Siddharudha

    2016-01-01

    Background Owing to frequent outbreaks witnessed in different parts of the country in the recent past, scrub typhus is being described as a re-emerging infectious disease in India. Differentiating scrub typhus from other endemic diseases like malaria, leptospirosis, dengue fever, typhoid, etc. is difficult due to overlapping clinical features and a lower positivity for eschars in Asian populations. Hence, the diagnosis heavily relies on laboratory tests. Discussion Costs and the need of techn...

  13. Interactions between climate and land use which drive dynamics in treeline ecotone scrub in Scotland

    OpenAIRE

    Gilbert, Diana

    2011-01-01

    Treeline ecotone scrub, the suite of tall woody plant communities that bridge the boundary between tall forest and higher altitude open summit heaths, is a rare and little studied transition habitat in the UK. Individual species have recently attracted emergency measures to secure their future, but little is known about the current dynamics of the habitats. This thesis increases knowledge of treeline scrub dynamics, particularly in relation to young plants, and develops an unde...

  14. 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.

  15. 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 ...

  16. 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...

  17. 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.

  18. CO2 emissions and mitigation potential in China's ammonia industry

    International Nuclear Information System (INIS)

    Significant pressure from increasing CO2 emissions and energy consumption in China's industrialization process has highlighted a need to understand and mitigate the sources of these emissions. Ammonia production, as one of the most important fundamental industries in China, represents those heavy industries that contribute largely to this sharp increasing trend. In the country with the largest population in the world, ammonia output has undergone fast growth spurred by increasing demand for fertilizer of food production since 1950s. However, various types of technologies implemented in the industry make ammonia plants in China operate with huge differences in both energy consumption and CO2 emissions. With consideration of these unique features, this paper attempts to estimate the amount of CO2 emission from China's ammonia production, and analyze the potential for carbon mitigation in the industry. Based on the estimation, related policy implications and measures required to realize the potential for mitigation are also discussed.

  19. Electrolytes and Electrodes for Electrochemical Synthesis of Ammonia

    DEFF Research Database (Denmark)

    Lapina, Alberto

    effective energy storage solutions. Production of synthetic fuels (e.g. ammonia) is a promising possibility. Ammonia (NH3) can be an interesting energy carrier, thanks to its high energy density and the existence of well developed storage and transportation technologies. However the present-day production...... technology is based on the Haber-Bosch process, which is energy intensive and requires large-scale plants. One possible way to produce ammonia from sustainable electricity, nitrogen and hydrogen/water is using an electrochemical cell. This thesis studies a number of electrolytes and electrocatalysts to...... evaluate their applicability to electrochemical synthesis of ammonia. First a number of potential electrolytes are investigated in the temperature range 25-400°C in order to find a proton conductor with a conductivity higher than 10-4 S/cm in dry atmosphere (pH2O < 0.001 atm). The conductivity of materials...

  20. Rapid Increase in Scrub Typhus Incidence in Mainland China, 2006-2014.

    Science.gov (United States)

    Wu, Yi-Cheng; Qian, Quan; Magalhaes, Ricardo J Soares; Han, Zhi-Hai; Haque, Ubydul; Weppelmann, Thomas A; Hu, Wen-Biao; Liu, Yun-Xi; Sun, Yan-Song; Zhang, Wen-Yi; Li, Shen-Long

    2016-03-01

    Scrub typhus is a vector-borne disease, which has recently reemerged in China. In this study, we describe the distribution and incidence of scrub typhus cases in China from 2006 to 2014 and quantify differences in scrub typhus cases with respect to sex, age, and occupation. The results of our study indicate that the annual incidence of scrub typhus has increased during the study period. The number of cases peaked in 2014, which was 12.8 times greater than the number of cases reported in 2006. Most (77.97%) of the cases were reported in five provinces (Guangdong, Yunnan, Anhui, Fujian, and Shandong). Our study also demonstrates that the incidence rate of scrub typhus was significantly higher in females compared to males (P age group, and that farmers had a higher incidence rate than nonfarmers (P < 0.001). Different seasonal trends were identified in the number of reported cases between the northern and southern provinces of China. These findings not only demonstrate that China has experienced a large increase in scrub typhus incidence, but also document an expansion in the geographic distribution throughout the country. PMID:26711517

  1. Photosynthetic 14C fixation in leaves and isolated chloroplasts of some scrub species under the influence of paraquat and 2,4,5-T

    International Nuclear Information System (INIS)

    The diurnal course of carbon dioxide uptake in the leaves of six nonsucculent semiarid scrub species was investigated. Five nonsucculent scrub species, Carissa spinarum, Maba buxifolia, Flacourtia sepiaria, Gymnosporia emerginata and Dodonaea viscosa exhibited nocturnal carbon assimilation while day time CO2 uptake was predominant in Chomelia asiatica. Foliar application of paraquat (100 mg 1sup(-1)) or 2,4,5-T (2000 mg 1sup(-1)) caused a marked inhibition in the dark uptake of CO2. On the other hand, carbon uptake during day was slightly reduced. Studies on the carbon assimilation of isolated chloroplasts under the influence of paraquat or 2,4,5-T revealed that paraquat is more effective than 2,4,5-T in the suppression of carbon assimilation of in vivo and in vitro chloroplasts. The data suggested that the process of nocturnal carbon assimilation is far more sensitive to paraquat than the light dependent carbon fixation during day. (author)

  2. 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...

  3. 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

  4. 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.

  5. Management of solid wastes from the Limestone Injection Dry Scrubbing (LIDS) clean coal technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Musiol, W.F. Jr.; Czuczwa, J.M.

    1993-03-01

    The objectives of this project were to characterize by-products from a pilot Limestone Injection Dry Scrubbing (LIDS) process and to develop processes directed toward the safe and economic use or disposal of these wastes. Because LIDS is a developing Clean Coal technology, a database of chemical and physical characteristics of the by-product was first developed. During the course of this project, it was found that the waste alone did not form high-strength products sufficient for use in construction and engineering applications. Therefore, the project was redirected to evaluate the by-product as a soil-cement and Portland cement raw material, agricultural liming agent, backfill/landfill material component, and mine reclamation/neutralizing agent. Based on these evaluations, the most viable uses for the LIDS byproduct include use in mine reclamation or as a neutralization agent. If soluble sulfites can be minimized by avoiding a dolomitic LIDS reagent, use as an agricultural liming agent has promise. Interest from an Ohio utility in the LIDS process suggests possible application of results at the demonstration or commercial stages.

  6. Evolutionary and demographic history of the Californian scrub white oak species complex: an integrative approach.

    Science.gov (United States)

    Ortego, Joaquín; Noguerales, Víctor; Gugger, Paul F; Sork, Victoria L

    2015-12-01

    Understanding the factors promoting species formation is a major task in evolutionary research. Here, we employ an integrative approach to study the evolutionary history of the Californian scrub white oak species complex (genus Quercus). To infer the relative importance of geographical isolation and ecological divergence in driving the speciation process, we (i) analysed inter- and intraspecific patterns of genetic differentiation and employed an approximate Bayesian computation (ABC) framework to evaluate different plausible scenarios of species divergence. In a second step, we (ii) linked the inferred divergence pathways with current and past species distribution models (SDMs) and (iii) tested for niche differentiation and phylogenetic niche conservatism across taxa. ABC analyses showed that the most plausible scenario is the one considering the divergence of two main lineages followed by a more recent pulse of speciation. Genotypic data in conjunction with SDMs and niche differentiation analyses support that different factors (geography vs. environment) and modes of speciation (parapatry, allopatry and maybe sympatry) have played a role in the divergence process within this complex. We found no significant relationship between genetic differentiation and niche overlap, which probably reflects niche lability and/or that multiple factors, have contributed to speciation. Our study shows that different mechanisms can drive divergence even among closely related taxa representing early stages of species formation and exemplifies the importance of adopting integrative approaches to get a better understanding of the speciation process. PMID:26547661

  7. 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/...

  8. Prevention of intraoperative wound contamination with chlorhexidine shower and scrub.

    Science.gov (United States)

    Garibaldi, R A

    1988-04-01

    In a prospective, controlled, clinical trial, we found that preoperative showering and scrubbing with 4% chlorhexidine gluconate was more effective than povidone-iodine or triclocarban medicated soap in reducing skin colonization at the site of surgical incision. Mean log colony counts of the incision site were one half to one log lower for patients who showered with chlorhexidine compared to those who showered with the other regimens. No growth was observed on 43% of the post shower skin cultures from patients in the chlorhexidine group compared with 16% of the cultures from patients who had povidone-iodine showers and 5% of those from patients who used medicated soap and water. The frequency of positive intraoperative wound cultures was 4% with chlorhexidine, 9% with povidone-iodine and 14% with medicated soap and water. This study demonstrates that chlorhexidine gluconate is a more effective skin disinfectant than either povidone-iodine or triclocarban soap and water and that its use is associated with lower rates of intraoperative wound contamination. PMID:2898503

  9. 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.

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

    Science.gov (United States)

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

    2015-09-15

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

  11. 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...

  12. 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

  13. 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.

  14. 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

  15. Application of Vertical Stirred Mill in Foam Scrubbing of Molybdenum Cleaning%立式螺旋搅拌磨机在钼精选泡沫擦洗中的应用

    Institute of Scientific and Technical Information of China (English)

    王漪靖; 俞国庆

    2011-01-01

    介绍了立式螺旋搅拌磨机的基本结构、工作原理及其在钼精选泡沫擦洗中的应用.根据立式磨摩擦研磨、剪切力强的特点,将其应用于钼精选段的泡沫擦洗,通过磨剥和擦洗清除掉矿物表面过多的油药,打开泡沫聚团,使辉钼矿与杂质有效分离,提高了钢精矿品位和同收率.实践证明立式螺旋搅拌磨机用于钼精矿泡沫擦洗技术可行,效果显著.%Basic structure, working mechanism of vertical stirred mill ( VSM ) and its application for foam scrubbing in the cleaning process of molybdenum flotation were introduced. VSM possesses characteristics of rubbing grinding and strong shear force, and has been used for foam scrubbing in cleaning process of molybdenum flotation. Conseguently excess mineral oil medicine coated on minerals can be peeled, scrubbed and washed down, and the bubble agglomeration can be disrupted and dispersed, molybdenum can be effectively beneficiated from the gangues, therewith the grade and recovery of molybdenum concentrate can be increased. This practice verified that it is technically feasible and effective to use VSM for foam scrubbing of molybdenum concentrate.

  16. Hemophagocytic lymphohistiocytosis: an unusual complication in Orientia tsutsugamushi disease (scrub typhus.

    Directory of Open Access Journals (Sweden)

    Aneesh Basheer

    2014-12-01

    Full Text Available Background: Hemophagocytic lymphohistiocytosis (HLH is an uncommon, potentially fatal, hyperinflammatory syndrome that may rarely complicate the clinical course of Orientia tsutsugamushi disease (scrub typhus. Methods: We describe here the clinicopathological features, laboratory parameters, management, and outcome data of three adult patients (1 female, 2 males with scrub typhus associated HLH from a tertiary center with a brief and concise review of international literature. Results: All three patients satisfied the HLH-2004 diagnostic criteria; one had multi organ dysfunction with “sky high” ferritin level; and all had a dramatic recovery following doxycyclin therapy. Literature review from January 1990 to March 2014 revealed that scrub typhus associated HLH were reported in 21 patients, mostly from the scrub endemic countries of the world. These included 11 females and 10 males with mean age of 35 years (range; 8 months to 81 years. Fifteen of 17 patients (where data was available had a favorable outcome following early serological diagnosis and initiation of definitive antibiotic therapy with (N=6 or without (N=9 immunosuppressive/immunomodulator therapy. Mutation analysis for primary HLH was performed in one patient only, and HLH-2004 protocol was used in two patients. Conclusion: We suggest that HLH should be considered in severe cases of scrub typhus especially if associated with cytopenia (s, liver dysfunction, and coagulation abnormalities.  Further studies are required to understand whether an immunosuppressive and/or immunomodulator therapy could be beneficial in those patients who remain unresponsive to definitive antibiotic therapy.

  17. Outbreak of scrub typhus in southern India during the cooler months.

    Science.gov (United States)

    Mathai, E; Rolain, J M; Verghese, G M; Abraham, O C; Mathai, D; Mathai, M; Raoult, D

    2003-06-01

    Orientia tsutsugamushi, the agent of scrub typhus, is a strict intracellular bacterium which is found in many parts of Asia including India. During the past few years, the number of patients with rickettsial infection and scrub typhus has increased, especially during the cooler months. We report in this study a recent outbreak of scrub typhus recorded during the cooler months (October 2001 to February 2002) in patients admitted to our hospital with acute febrile illness associated with diverse signs and symptoms. Overall, 28 patients were clinically and serologically confirmed to have scrub typhus. Fever for more than one week was the only common manifestation. Myalgias was the next most common feature (52%), and rash was observed in only 22% of the cases. Seventeen patients treated with doxycycline recovered in 1 to 3 days, as well as two patients who received chloramphenicol. In five patients who received ciprofloxacin, fever subsided only after five days. Finally three patients (10.7%) died, including one patient treated with doxycycline. These data indicate that scrub typhus is a reemerging infectious disease in India with a possibility of drug resistance. This reemergence emphasizes the need for further prospective studies to design effective control measures. PMID:12860654

  18. 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

  19. 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.

  20. Innovative bioelectrochemical-anaerobic-digestion integrated system for ammonia recovery and bioenergy production from ammonia-rich residues

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2015-01-01

    Ammonia (NH4+/NH3) inhibition during anaerobic digestion process is one of the most frequent problems existing in biogas plants, resulting in unstable process and reduced biogas production. In this study, we developed a novel hybrid system, consisted of a submersed microbial resource recovery cell...

  1. Scrub typhus in adults in a teaching hospital in north Karnataka, 2011-2012

    Directory of Open Access Journals (Sweden)

    Umesh G Rajoor

    2013-01-01

    Full Text Available Background and Objectives: Scrub typhus is grossly under-diagnosed in India due to its non specific clinical presentation, limited awareness and low index of suspicion among clinicians, and lack of diagnostic facilities. As there is a resurgence of scrub typhus in this part of north Karnataka, an attempt is made to study the clinical prolife and complications of scrub typhus in adult patients. Materials and Methods: All cases of febrile illness diagnosed as scrub typhus over a period of 1 year were analysed. Diagnosis was based on the presence of the eschar and /or positive Weil Felix test with a titre of > 1:80. Results: 50 patients diagnosed to have scrub typhus during study period of one year were included in the study. Headache, myalgia, nausea, vomiting and dry cough were common symptoms. More than half of the patients had fever of 7-14 days duration (54%. Eschar was seen only in six patients. Transaminitis was noted in 86.67% patients. Weil Felix test was positive in 48/50 patients with titers of 1:160 in 13 patients, 1:320 in 31 patients and 1:640 in 4 patients. In our study complications noted were acute renal failure (07cases, ARDS and encephalitis 04 cases each and septic shock 01 case. Conclusion: There is a resurgence of scrub typhus in this part of north Karnataka, as one of the important cause of acute febrile illness. Weil Felix test serves as a useful and cheap test for the laboratory diagnosis of Rickettsial disease.

  2. Recent outbreak of scrub typhus in North Western part of India

    Directory of Open Access Journals (Sweden)

    Parul Sinha

    2014-01-01

    Full Text Available Background: Scrub typhus usually affects previously healthy active persons and if undiagnosed or diagnosed late, may prove to be life-threatening. Diagnosis of scrub typhus should be largely based on a high index of suspicion and careful clinical, laboratory and epidemiological evaluation. Objective: To describe the diverse clinical and laboratory manifestations of scrub typhus diagnosed in Mahatma Gandhi Medical College and Hospital, Jaipur. Materials and Methods: All cases of febrile illness diagnosed as scrub typhus over a period of 3 months were analysed. Diagnosis was based on ELISA test for antibody detection against 56 kDa antigen. Results: Forty-two cases of scrub typhus were seen over a period of 3 months (October, 2012-December, 2012. Common symptoms were high grade fever of 4-30 days duration, cough, haemoptysis and breathlessness. Eschar was not seen even in a single patient. Liver enzymes were elevated in nearly all cases (95.9%. Multiple organ dysfunction syndrome (MODS was present in 16.66% of our patients (7 out of 42. Hypotension (6 patients, 14.2%, renal impairment (9 out of 15 patients, 60%, acute respiratory distress syndrome (4 patients, 9.52% and meningitis (4 patients, 9.52% were some of the important complications. There was a dramatic response to doxycycline in nearly all the patients, but initially when the disease was not diagnosed, seven patients had died. Conclusion: Scrub typhus has emerged as an important cause of febrile illness in Jaipur. Empirical treatment with doxycycline is justified in endemic areas.

  3. Does a robotic scrub nurse improve economy of movements?

    Science.gov (United States)

    Wachs, Juan P.; Jacob, Mithun; Li, Yu-Ting; Akingba, George

    2012-02-01

    Objective: Robotic assistance during surgery has been shown to be a useful resource to both augment the surgical skills of the surgeon through tele-operation, and to assist the surgeon handling the surgical instruments to the surgeon, similar to a surgical tech. We evaluated the performance and effect of a gesture driven surgical robotic nurse in the context of economy of movements, during an abdominal incision and closure exercise with a simulator. Methods: A longitudinal midline incision (100 mm) was performed on the simulated abdominal wall to enter the peritoneal cavity without damaging the internal organs. The wound was then closed using a blunt needle ensuring that no tissue is caught up by the suture material. All the instruments required to complete this task were delivered by a robotic surgical manipulator directly to the surgeon. The instruments were requested through voice and gesture recognition. The robotic system used a low end range sensor camera to extract the hand poses and for recognizing the gestures. The instruments were delivered to the vicinity of the patient, at chest height and at a reachable distance to the surgeon. Task performance measures for each of three abdominal incision and closure exercises were measured and compared to a human scrub nurse instrument delivery action. Picking instrument position variance, completion time and trajectory of the hand were recorded for further analysis. Results: The variance of the position of the robotic tip when delivering the surgical instrument is compared to the same position when a human delivers the instrument. The variance was found to be 88.86% smaller compared to the human delivery group. The mean task completion time to complete the surgical exercise was 162.7+/- 10.1 secs for the human assistant and 191.6+/- 3.3 secs (Pnurse assistant improves the surgical procedure by reducing the number of movements (lower variance in the picking position). The variance of the picking point is closely

  4. 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...

  5. 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

  6. 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.

  7. 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...... 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....

  8. SAMPLE RESULTS FROM THE NEXT GENERATION SOLVENT PROGRAM REAL WASTE EXTRACTION-SCRUB-STRIP TESTING

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T.; Washington, A.

    2013-06-03

    Savannah River National Laboratory (SRNL) performed multiple Extraction-Scrub-Strip (ESS) testing using real waste solutions, and three Next Generation Solvent (NGS) variations, which included radiologically clean pure NGS, a blend of radiologically clean NGS and radiologically clean BOBCalixC6 (NGS-MCU), and a blend of radiologically clean NGS and radiologically contaminated BOBCalixC6 from the MCU Solvent system. The results from the tests indicate that both the NGS and the NGS-MCU blend exhibit adequate extraction, scrub and strip behavior.

  9. Sample Results From The Next Generation Solvent Program Real Waste Extraction-Scrub-Strip Testing

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T. B.; Washington, A. L. II

    2013-08-08

    Savannah River National Laboratory (SRNL) performed multiple Extraction-Scrub-Strip (ESS) testing using real waste solutions, and three Next Generation Solvent (NGS) variations, which included radiologically clean pure NGS, a blend of radiologically clean NGS and radiologically clean BOBCalixC6 (NGS-MCU), and a blend of radiologically clean NGS and radiologically contaminated BOBCalixC6 from the MCU Solvent system. The results from the tests indicate that both the NGS and the NGS-MCU blend exhibit adequate extraction, scrub and strip behavior.

  10. 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

  11. Electrolytic removal of ammonia from aqueous phase by Pt/Ti anode.

    Science.gov (United States)

    Li, Liang; Huang, Yuanxing; Liu, Yan; Li, Yangyang

    2013-01-01

    This study investigated the mechanism and kinetic modeling of electrolytic degradation of ammonia with Pt/Ti anode. The results show that ammonia oxidation from direct oxidation or indirect oxidation with hydroxyl radicals was slow but can be observed under pH 9 and high initial ammonia concentration of 1,050 mg N L(-1). Indirect oxidation with HOCl was the mechanism for the chloride-mediated electrolytic removal of ammonia. In this process, pH between 3 and 9 had little effect on the ammonia removal rate, but current density (j) and chloride concentration ([Cl(-)]) showed a linear relationship with ammonia removal rate within the range of 3.8-15.4 mA cm(-2) and 30-300 mg L(-1), respectively. The ammonia removal could be described by a pseudo-zero order kinetics with a mathematic equation of k = 0.0003 × [Cl(-)] × j - 0.076. Treatment of the actual wastewater effluent from a secondary clarifier in a local wastewater treatment plant showed an ammonia removal rate of 0.8 mg N L(-1) h(-1) and energy cost of 14 kJ per mg N ammonia. PMID:23752376

  12. 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.

  13. 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. PMID:26490748

  14. 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

  15. 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.

  16. 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.

  17. Amine substitution into sulfuric acid – ammonia clusters

    Directory of Open Access Journals (Sweden)

    H. Vehkamäki

    2012-04-01

    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.

  18. 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.

  19. 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.

  20. 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%....

  1. 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.

  2. 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.

  3. 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...

  4. Ammonia dynamics in magnesium ammine from DFT and neutron scattering

    DEFF Research Database (Denmark)

    Tekin, Adem; Hummelshøj, Jens Strabo; Jacobsen, Hjalte Sylvest;

    2010-01-01

    Energy storage in the form of ammonia bound in metal salts, so-called metal ammines, combines high energy density with the possibility of fast and reversible NH3 ab- and desorption kinetics. The mechanisms and processes involved in the NH3 kinetics are investigated by density functional theory (D...

  5. Differences in Attentional Strategies by Novice and Experienced Operating Theatre Scrub Nurses

    Science.gov (United States)

    Koh, Ranieri Y. I.; Park, Taezoon; Wickens, Christopher D.; Ong, Lay Teng; Chia, Soon Noi

    2011-01-01

    This study investigated the effect of nursing experience on attention allocation and task performance during surgery. The prevention of cases of retained foreign bodies after surgery typically depends on scrub nurses, who are responsible for performing multiple tasks that impose heavy demands on the nurses' cognitive resources. However, the…

  6. Severity Predictors in Eschar-Positive Scrub Typhus and Role of Serum Osteopontin

    OpenAIRE

    Park, Sang-Won; Lee, Chang-Seop; Lee, Chi Kug; Kwak, Yee Gyung; Moon, Chisook; Kim, Baek-Nam; Kim, Eu Suk; Kang, Jae Myung; Oh, Myoung-don

    2011-01-01

    We prospectively evaluated severity predictors in terms of host, microorganism, and treatment factors in 153 eschar-positive scrub typhus patients. Severity was assessed with the Acute Physiology and Chronic Health Evaluation (APACHE) II score ( 100 ng/mL, and a g...

  7. Scrub Typhus in Adults – A Case Series from a Tertiary Care Hospital

    Directory of Open Access Journals (Sweden)

    Sudhakar M K

    2011-04-01

    Full Text Available Introduction: Scrub typhus is a zoonosis caused by the rickettsial bacteria Orientia tsutsugamushi. The disease in endemic in many parts of India and continues to be a public health problem. Materials and Methods: This study describes the clinical profile of eight consecutive scrub typhus positive cases admitted in a tertiary care hospital. After complete physical examination, complete blood count, liver function tests, renal function tests, urine analysis, blood & urine cultures were done in all cases. In all the cases, scrub typhus was diagnosed using a rapid single step immunochromatographic assay. Results: Of eight cases five were females and three were males. Fever was the chief present symptom in all the cases. Other signs and symptoms were headache, myalgia, cough, hepatosplenomegaly, abdominal pain and lymphadenopathy. Eschar was present in all the cases. Liver enzymes were elevated in all the patients. Hypotension, thrombocytopenia, hepatic dysfunction, hypoalbuminemia, hematuria and proteinuria were the complications observed. All cases were successfully treated with doxycycline and there was no mortality. Conclusion: Our report emphasizes the fact that a diagnosis of scrub typhus should be suspected when a patient presents with fever and laboratory evidence of liver dysfunction, as early detection of the disease could reduce morbidity and mortality.

  8. Comparison of surgical hand scrub and alcohol surgical hand rub on reducing hand microbial burden.

    Science.gov (United States)

    Ghorbani, Azam; Shahrokhi, Akram; Soltani, Zahra; Molapour, Azam; Shafikhani, Mahin

    2012-02-01

    This study was performed to compare the effects of two hand decontamination methods on the microbial burden of operating room staff hands. The surgical hand washing methods compared were a traditional surgical hand scrub using a povidone iodine solution, and a social wash using a liquid non-antibacterial soap followed by the application of an alcoholic hand rub. PMID:22724306

  9. Coincidence between geographical distribution of Leptotrombidium scutellare and scrub typhus incidence in South Korea.

    Directory of Open Access Journals (Sweden)

    Jong Yul Roh

    Full Text Available To clarify the geographical distribution of scrub typhus vectors in Korea, a survey of larval trombiculid mites was conducted from 2005 to 2007 by collecting wild small mammals twice a year (spring and autumn at 24 sites nationwide. A total of 67,325 mites representing 4 genera and 14 species were collected from 783 trapped rodents, corresponding to a chigger index (number of chigger mites per rodent of 86.0. The predominant mite species were Leptotrombidium pallidum (52.6%, Leptotrombiduim scutellare (27.1%, Leptotrombidium palpale (8.2%, Leptotrombidium orientale (5.6%, and Neotrombicula tamiyai (1.7%. However, the proportions of L. scutellare in southern areas, including endemic provinces such as Jeollabuk-Do (34.3%, Jeollanam-Do (49.0%, and Gyeongsangnam-Do (88%, were relatively higher than in central Korean regions where L. pallidum was predominant. In autumn, the ratio of L. scutellare increased to 42% while the ratio of L. pallidum decreased. The geographical distribution map of the L. scutellare chigger index was identical to the incidence pattern of scrub typhus, whereas those of overall mites and L. pallidum showed no relationship with case incidence patterns. Distribution mapping analysis shows an identical geographical distribution of L. scutellare and epidemic incidence of scrub typhus in South Korea. L. pallidum could be another vector at all other parts of the Korean peninsula, including the eastern and northern regions that have a low level of scrub typhus incidence.

  10. Anaerobic ammonia removal in presence of organic matter: A novel route

    International Nuclear Information System (INIS)

    This study describes the feasibility of anaerobic ammonia removal process in presence of organic matter. Different sources of biomass collected from diverse eco-systems containing ammonia and organic matter (OM) were screened for potential anaerobic ammonia removal. Sequential batch studies confirmed the possibility of anaerobic ammonia removal in presence of OM, but ammonia was oxidized anoxically to nitrate (at oxidation reduction potential; ORP -248 ± 25 mV) by an unknown mechanism unlike in the reported anammox process. The oxygen required for oxidation of ammonia might have been generated through catalase enzymatic activity of facultative anaerobes in mixed culture. The oxygen generation possibility by catalase enzyme route was demonstrated. Among the inorganic electron acceptors (NO2-, NO3- and SO42-) studied, NO2- was found to be most effective in total nitrogen removal. Denitrification by the developed culture was much effective and faster compared to ammonia oxidation. The results of this study show that anaerobic ammonia removal is feasible in presence of OM. The novel nitrogen removal route is hypothesized as enzymatic anoxic oxidation of NH4+ to NO3-, followed by denitrification via autotrophic and/or heterotrophic routes. The results of batch study were confirmed in continuous reactor operation

  11. 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

  12. 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

  13. Multistate modeling of habitat dynamics: Factors affecting Florida scrub transition probabilities

    Science.gov (United States)

    Breininger, D.R.; Nichols, J.D.; Duncan, B.W.; Stolen, Eric D.; Carter, G.M.; Hunt, D.K.; Drese, J.H.

    2010-01-01

    Many ecosystems are influenced by disturbances that create specific successional states and habitat structures that species need to persist. Estimating transition probabilities between habitat states and modeling the factors that influence such transitions have many applications for investigating and managing disturbance-prone ecosystems. We identify the correspondence between multistate capture-recapture models and Markov models of habitat dynamics. We exploit this correspondence by fitting and comparing competing models of different ecological covariates affecting habitat transition probabilities in Florida scrub and flatwoods, a habitat important to many unique plants and animals. We subdivided a large scrub and flatwoods ecosystem along central Florida's Atlantic coast into 10-ha grid cells, which approximated average territory size of the threatened Florida Scrub-Jay (Aphelocoma coerulescens), a management indicator species. We used 1.0-m resolution aerial imagery for 1994, 1999, and 2004 to classify grid cells into four habitat quality states that were directly related to Florida Scrub-Jay source-sink dynamics and management decision making. Results showed that static site features related to fire propagation (vegetation type, edges) and temporally varying disturbances (fires, mechanical cutting) best explained transition probabilities. Results indicated that much of the scrub and flatwoods ecosystem was resistant to moving from a degraded state to a desired state without mechanical cutting, an expensive restoration tool. We used habitat models parameterized with the estimated transition probabilities to investigate the consequences of alternative management scenarios on future habitat dynamics. We recommend this multistate modeling approach as being broadly applicable for studying ecosystem, land cover, or habitat dynamics. The approach provides maximum-likelihood estimates of transition parameters, including precision measures, and can be used to assess

  14. Scrub typhus caused by Orientia tsutsugamushi Kawasaki-related genotypes in Shandong Province, northern China.

    Science.gov (United States)

    Zhang, Luyan; Bi, Zhenwang; Kou, Zengqiang; Yang, Huili; Zhang, Aihua; Zhang, Shoufeng; Meng, Xiangpeng; Zheng, Li; Zhang, Meng; Yang, Hui; Zhao, Zhongtang

    2015-03-01

    Orientia tsutsugamushi, the causative agent of scrub typhus, is an obligate intracellular bacterium and characterized by dramatic genetic diversity. To elucidate the genotypes of O. tsutsugamushi populating in patients in Shandong Province, a new epidemic zone in China, we sequenced partial of the 56-kDa type-specific antigen gene (TSA) and identified the genotypes of 43 O. tsutsugamushi samples from human patients confirmed with scrub typhus from 2010 to 2013. All of the 43 sequences are in the same clade, 39 of them are in one branch and the other four sequences, nominated as SH1002, SH1306, SH1309, and SH1307 are in four separate branches. To clarify the clinical characterizations caused by Kawasaki-related genotypes, we studied the clinical profiles of these 43 scrub typhus patients. Most patients (88.1%) were farmers lived in rural areas. They presented with fever (100.0%), headache (79.1%), dizziness (32.6%), generalized myalgia (48.8%), fatigue (53.5%), anorexia (53.5%), facial flushing (23.3%), conjunctival congestion (11.6%), skin rashes (58.1%) and lymphadenopathy (23.3%). Eschar (97.7%) was quite common in patients, which provided doctors with a luminous clue for diagnosis of scrub typhus. Thrombocytopenia was seen in 23.1% of patients, and three patients (7.0%) had bronchopneumonia. There was no death report in Shandong Province during the study period. The present study provides beneficial data for clinical, serological, and molecular diagnosis of scrub typhus infections, and also provides foundations for subsequent studies. PMID:25575441

  15. Bacterial Agents Andantibiogram of Most Common Isolated Organisms from Hands of Surgical Team Members after Scrubbing

    Directory of Open Access Journals (Sweden)

    PS Mohseni- Meybodi

    2008-04-01

    Full Text Available Introduction: Many post-surgical wound infections in hospitals cause morbidity and morality of patients and these are usually transmitted via hands of surgical personnel. The aim of the present study was to detect and antibiogram the bacterial agents following scrubbing of hands of surgical personnel before operation. Methods: Hands of 134 personnels of operation room were swabbed following scrubbing with antiseptic Betadine solution. Swab samples were inoculated on selective and differential media such as blood ager, McConky and manitol salt agar(MSA. Following incubation of media at 37c° for 24hr, bacterial species were identified using differential related tests. The isolated species were than antibiogramed and the results together with other data was analysed by SPSS software program. Results: Of the total of 134 cases, 81(60.4% were male and 53(39.6% female. The mean scrub time for each person was (206.1+/-103.2 seconds; 6 to 60 seconds base change. Increasing time of scrub was significantly correlated with decreasing rate of bacteria (P=0.003, (R=-0.254. Contamination was present in 129(96.3% cases following scrubbing. Maximum contamination was observed in nails (92.5%. Average number of bacteria for each individual was between 0 and 159. 62.6% of isolated bacteria were non- staphylococci and 7.7% were S. aureus. Vancomycin and ceftizoxim were the most sensitive, while penicillin was the least sensitive antibiotic. Conclusion: Results revealed that hand contamination was more than the expected standard level. Therefore, regarding the critical task of surgical personnel, training of all operation room staff is highly recommended to minimize the rate of contamination.

  16. Superionic water-ammonia mixtures

    Science.gov (United States)

    Bethkenhagen, M.; Cebulla, D.; Redmer, R.; Hamel, S.

    2014-12-01

    The interior of the Giant Planets Uranus and Neptune contains large amounts of water, ammonia and methane (referred to as planetary ices). Many observable properties of these planets, such as luminosity, gravitational moments and magnetic fields, are thought to be determined by the physical and chemical properties of matter within this ice layer. Hence, the phase diagrams, equations of state and structural properties of these materials and their respective mixtures are of great interest.Especially the phase diagrams of water and ammonia gained much attention since Cavazzoni et al. [1] proposed superionic phases for these materials, which are characterized by highly mobile hydrogen ions in a lattice of oxygen and nitrogen ions, respectively. For water, the influence of such a phase on the properties of the Giant Planets as well as on exoplanets has been discussed widely. [2,3] Nevertheless, it is an open question how the properties of such a water layer change when another compound, e.g., ammonia is introduced. Considering a 1:1 mixture, we have performed ab initio simulations based on density functional theory using the VASP code [4] heating up structures which we had found from evolutionary random structure search calculations with XtalOpt [5]. We propose possible superionic water-ammonia structures present up to several Mbar. Moreover, we investigate the equation of state and transport properties of this mixture such as diffusion coefficients in order to compare with the pure compounds. These results are essential to construct new interior models for Neptune-like planets.[1] C. Cavazzoni et al., Science 283, 44 (1999).[2] R. Redmer et al., Icarus 211, 798 (2011).[3] L. Zeng and D. Sasselov, ApJ 784, 96 (2014).[4] G. Kresse and J. Hafner, Phys. Rev. B 47, 558 (1993).[5] D. C. Lonie and E. Zurek, Comput. Phys. Commun. 182, 372 (2011).

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

    OpenAIRE

    Ip, Yuen K.; 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...

  18. 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

  19. 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.

  20. Fluorographene based Ultrasensitive Ammonia Sensor.

    Science.gov (United States)

    Tadi, Kiran Kumar; Pal, Shubhadeep; Narayanan, Tharangattu N

    2016-01-01

    Single molecule detection using graphene can be brought by tuning the interactions via specific dopants. Electrostatic interaction between the most electronegative element fluorine (F) and hydrogen (H) is one of the strong interactions in hydrogen bonding, and here we report the selective binding of ammonia/ammonium with F in fluorographene (FG) resulting to a change in the impedance of the system. Very low limit of detection value of ~0.44 pM with linearity over wide range of concentrations (1 pM-0.1 μM) is achieved using the FG based impedance sensor, andthisscreen printed FG sensor works in both ionized (ammonium) and un-ionized ammonia sensing platforms. The interaction energies of FG and NH3/NH4(+) are evaluated using density functional theory calculations and the interactions are mapped. Here FGs with two different amounts of fluorinecontents -~5 atomic% (C39H16F2) and ~24 atomic% (C39H16F12) - are theoretically and experimentally studied for selective, high sensitive and ultra-low level detection of ammonia. Fast responding, high sensitive, large area patternable FG based sensor platform demonstrated here can open new avenues for the development of point-of-care devices and clinical sensors. PMID:27142522

  1. 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.

  2. Investigating the Efficiency of Biological Filters for Ammonia Removal

    Directory of Open Access Journals (Sweden)

    S Motesaddi Zarandi, MR Massoudinejad, A Mazaheri Tehrani, H Pouri

    2013-09-01

    Full Text Available Backgrounds and Aims: Ammonia removal from air to prevent severe damage to the environment and living organisms is very important. Biofiltration is an efficient, easy, cost-effective, and environmentally friendly process for degradation of ammonia from waste air. The aim of this study is to investigate the efficiency of biological filtration using a compost and scallop bed for ammonia removal. Materials and Methods: According to the ammonia removal method a column with 14cm inner diameter and 45cm height made from transparent Plexiglas was used. The column was filled up to 25 cm with compost and scallop (with a scallop: compost ratio of 1:4. In this study, performance of the biofilter was studied under 10 different flow rates (1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 lit/min and 5 different concentrations (0-20, 20-40, 40-60, 60-80 and 80-100 ppm at a temperature of 25 degrees Celsius. Results: The results of this study showed that efficiency is decreased when the flow rate or concentration is increased because the microbial population is reduced. The efficiency was reduced by 84.6-98.2 percent. Maximum efficiency occurred at a 0.19g/(m3.h loading rate. Efficiency was in 0-20 concentration intervals at a flow rate of 1 lit/min and at an Empty Bed Residence Time (EBRT of 240 seconds. Conclusion: The results show that a biofilter with a compost and scallop bed is efficient for ammonia removal from air. Results can be optimized in the design and operation of biological systems to be used in the industrial control of ammonia gas.

  3. Behavior of ammonia in hydrocarbon flames and its influence on electrophysical phenomena during combustion

    Energy Technology Data Exchange (ETDEWEB)

    Tsoi, L.P.; Botova, V.I.; Fialkov, B.S.; Shcherbakova, N.D.

    1985-09-01

    Introduction of ammonia into flames provides information on the relationships between individual components of the process by comparison of the consequences of such action on combustion characteristeics. The concentration and distribution of atomic hydrogen and peroxy radicals in the flame were determined by the ESR method. Mass spectrometry was used for determination of positive ion, stable components were determined chromatographically, and the distribution of the electric flame potential was studied with the aid of a passive probe. Tables show distribution of the rate of ammonia consumption over flame radius, and dependence on the rate of ammonia consumption on the ammonia content in fuel-air mixtures. It is inferred from the results that charged species play an active part in the combustion mechanism and, in particular, in oxidation of ammonia.

  4. 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

  5. Laundering habits of student nurses and correlation with the presence of Staphylococcus aureus on nursing scrub tops pre- and postlaundering.

    Science.gov (United States)

    Scott, Elizabeth; Goodyear, Nancy; Nicoloro, Jennifer M; Marika, Desta J; Killion, Emma; Duty, Susan M

    2015-09-01

    Little is known about student nurse laundering practices. Student nurses swabbed their scrub tops after clinical and after laundering, and they completed a laundry survey; 13.5% of students wore the same scrub more than once, and few followed recommended guidelines by using hot water (20%) or bleach (5.6%) when laundering scrubs. After clinical shifts, 17% of swabs tested positive for Staphylococcus aureus; however, laundering eradicated it from 64.3% of positive samples. This was not statistically significant. PMID:26143576

  6. Clean air suits vs scrub suits: what are the benefits of using them for infection control in hospitals?

    OpenAIRE

    Abreu, Maria José

    2014-01-01

    Experts in infection control are often asked about issues related to the use of scrubs and clean air suits in the operating room (OR). So far there is no clear explanation or mandatory obligation why the surgical team has to wear clean air suits or scrub suits in the operating rooms (OR´s) and more importantly, what are the main differences between these two type of clothing. There is a general perception that the two are equal or very similar. So, what are clean air suits and scrub suits? Wh...

  7. First Report of an Orientia tsutsugamushi Type TA716–Related Scrub Typhus Infection in Thailand

    OpenAIRE

    McGready, Rose; Blacksell, Stuart D.; Luksameetanasan, Rungnapa; Wuthiekanun, Vanaporn; Jedsadapanpong, Wilairat; Day, Nicholas P J; Nosten, Francois

    2010-01-01

    Orientia tsutsugamushi causes scrub typhus and is a rural zoonosis endemic in the Asia Pacific region. This is the first report of O. tsutsugamushi TA716–like strain in a human in Thailand. The patient was in the 1st trimester of pregnancy when she developed scrub typhus. The O. tsutsugamushi strain TA716 was detected from her admission blood sample, and the pregnancy ended in spontaneous abortion. The effects of scrub typhus in pregnant women and the pregnancy outcome are sparsely documented...

  8. EKOLOGI PENYAKIT SCRUB TYPHUS DI UNIT DESA TRANSMIGRASI MULYOREJO, WAY ABUNG IH, LAMPUNG UTARA: SUATU PENELITIAN PENDAHULUAN

    Directory of Open Access Journals (Sweden)

    Tuti R. Hadi

    2012-09-01

    Full Text Available A preliminary study on the ecology of scrub typhus was conducted in a transmigration village Mulyorejo, Way AbungIII, Lampung Utara, Sumatra, Indonesia, in 1982. Serological examination on the human population revealed 11.9% seropositive against scrub typhus, being higher in males than in females, likewise also higher in adults than children. Seropositivity against scrub typhus among murid rodents captured was 42.9%. It was highest on Rattus exulans followed by Rattus tiomanicus. Two species of chigger vectors, Leptotrombidium (L. deliensis and Leptotrombidium (LJ fletcheri were found in the area studied. The infestation of those two species were highest on R. exulans and R. tiomanicus.

  9. 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)

  10. 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

  11. Extraction of DBP and MBP from actinides: application to the recovery of actinides from TBP--Na2CO3 scrub solutions

    International Nuclear Information System (INIS)

    A flowsheet for the recovery of actinides from TBP--Na2CO3 scrub waste solutions has been developed, based on batch extraction data, and tested, using laboratory scale counter-current extraction techniques. The process utilizes 2-ethyl-1-hexanol (2-EHOH) to extract the TBP degradation products (HDBP and H2MBP) from acidified Na2CO3 scrub waste leaving the actinides in the aqueous phase. Dibutyl and monobutyl phosphoric acids are attached to the 2-EHOH molecules through hydrogen bonds. These hydrogen bonds also diminish the ability of the HDBP and H2MBP to complex actinides and thus all actinides remain in the aqueous raffinate. Dilute sodium hydroxide solutions can be used to back-extract the dibutyl and monobutyl phosphoric acid esters as their sodium salts. The 2-EHOH can then be recycled. After extraction of the acidified carbonate waste with 2-EHOH, the actinides may be readily extracted from the raffinate with DHDECMP or, in the case of tetra- and hexavalent actinides, with TBP. The alcohol extraction (ARALEX) process is relatively simple and involves inexpensive and readily available chemicals. The ARALEX process can also be applied to other actinide waste streams which contain appreciable concentrations of polar organic compounds that interfere with conventional actinide ion exchange and liquid--liquid extraction procedures

  12. 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.

  13. 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...

  14. CLINICAL PROFILE OF PEDIATRIC SCRUB TYPHUS PATIENTS : A HOSPITAL BASED STUDY

    Directory of Open Access Journals (Sweden)

    Sunil Dutt

    2015-07-01

    Full Text Available BACKGROUND : Scrub typhus is an acute febrile illness caused by Orientia tsutsugamushi. The organism is transmitted during the bite of trombiculid mites. Field rodents are the reservoir hosts. The disease is endemic in many parts of India including the stat e of Jammu and Kashmir but is often under reported due to lack of diagnostic facilities. AIM: The aim was to study the clinical and epidemiological profile of pediatric scrub typhus patients reporting to the Department of Pediatrics, Government Medical College Jammu, a referral hospital for whole of Jammu region. METHODS : Prospective study conducted in the Department of Pediatrics Govt . Medical College Jammu from January 2011 to December 2011. A total of 90 children who reported with fever and rash or ly mphadenopathy or both were tested using qualitative ELISA for IgM antibodies against Orientia tsutsugamushi . The clinical and epidemiological profile of 74 pediatric scrub typhus patients who tested positive for IgM ELISA for Scrub typhus was studied. OBSE RVATION: Most ( 71.6% patients were in the age group of 6 - 15 years. 83% of them reported in the months of September and October. One third of the patients belonged to Rajouri district. Common physical signs were fever ( 100%, rash ( 86.4% and generalised l ymphadenopathy ( 83.7%. Others included conjuctival congestion ( 44.59%, hepatosplenomegaly ( 36.48%, jaundice ( 22.97%, edema ( 18.91%, eschar ( 17.56%, meningeal signs ( 10.81%, and myocarditis ( 5.4%.Most of the children presented late with complication s like hepatic dysfunction ( 55.4% , renal dysfunction ( 24.32 %, shock ( 4% meningoencephalitis ( 9.4%, gastrointestinal haemorrhage ( 8.1% and myocarditis ( 4.05 % , bronchopneumonia ( 4.05% and multiorgan involvement ( 2.7%. Children were treated with chloramphenicol or doxycycline. There was no mortality in the study group. CONCLUSION: Scrub typhus is endemic in the Jammu region especially Nowshera - Sunderbani - Rajouri belt

  15. Analysis of Ammonia Toxicity in Landfill Leachates

    OpenAIRE

    Takuya Osada; Keisuke Nemoto; Hiroki Nakanishi; Ayumi Hatano; Ryo Shoji; Tomohiro Naruoka; Masato Yamada

    2011-01-01

    Toxicity identification evaluation (TIE) phase I manipulations and toxicity test with D. magna were conducted on leachates from an industrial waste landfill site in Japan. Physicochemical analysis detected heavy metals at concentrations insufficient to account for the observed acute toxicity. The graduated pH and aeration manipulations identified the prominent toxicity of ammonia. Based on joint toxicity with additive effects of unionized ammonia and ammonium ions, the unionized ammonia toxic...

  16. 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...

  17. 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].

  18. Scrub Typhus with Acute Respiratory Distress Syndrome (ARDS) and its Management in Intensive Care Unit: A Case Report.

    Science.gov (United States)

    Sankuratri, Srinivas; Kalagara, Pavani; Samala, Kartika Balaji; Veledandi, Prabhakar Krishna; Atiketi, Srinadh Babu

    2015-05-01

    Scrub typhus is zoonotic disease caused by Orientia tsutsugamushi (O tsutsugamushi). It is transmitted to humans by the bite of trombiculid mite larvae (chiggers). It is a re-emerging infectious disease in India. Clinical manifestations include fever, headache, anorexia, myalgia, eschar, adenopathy and maculopapular rash. Complications of Scrub typhus develop after first week of illness. Complications include meningoencephalitis, jaundice, myocarditis, ARDS and renal failure. Eschar and rash may be unnoticed or absent. Thorough physical examination, identification of eschar/rash throws light in thinking about scrub typhus, treating and preventing further complications. Here, we report a case of scrub typhus with Acute Respiratory Distress Syndrome (ARDS) and its management with non invasive ventilation in the intensive care unit. PMID:26155511

  19. 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

  20. 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.

  1. 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.

  2. 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...

  3. Atmospheric amines and ammonia measured with a Chemical Ionization Mass Spectrometer (CIMS

    Directory of Open Access Journals (Sweden)

    Y. You

    2014-06-01

    Full Text Available We report ambient measurements of amines and ammonia with a~fast response chemical ionization mass spectrometer (CIMS in a southeastern US forest in Alabama and a~moderately polluted Midwestern site during the summer. In the Alabama forest, mostly C3-amines (from pptv to tens of pptv and ammonia (up to 2 ppbv were detected on a daily basis. C3-amines and ammonia showed similar diurnal trends and temperature and wind direction dependences, and were not associated with transported CO and SO2 plumes. Consistent with temperature dependences, amine and ammonia in the gas and aerosol phases showed opposite diurnal trends, indicating gas-to-particle partitioning of amines and ammonia. Temperature dependences also imply reversible processes of amines and ammonia evaporation from soil surfaces in daytime and deposition of amines and ammonia to soil surfaces at nighttime. Various amines (C1–C6 at the pptv level were observed in the transported biomass burning plumes, showing that biomass burning can be a substantial source of amines in the Southeast US. At the moderately polluted Kent site, higher concentrations of amines (C1–C6, from pptv to tens of pptv and ammonia (up to 6 ppbv were detected. Diurnal variations of C1- to C3-amines and ammonia were correlated with the ambient temperature. C4- to C6-amines showed abrupt increases during the nighttime, suggesting that they were emitted from local sources. These abundant amines and ammonia may in part explain the frequent new particle formation events reported from Kent. Lower amine concentrations at the rural forested site highlight the importance of constraining anthropogenic sources of amines.

  4. Atmospheric Amines and Ammonia Measured with a Chemical Ionization Mass Spectrometer (CIMS)

    Energy Technology Data Exchange (ETDEWEB)

    You, Y.; Kanawade, V. P.; de Gouw, J. A.; Guenther, Alex B.; Madronich, Sasha; Sierra-Hernandez, M. R.; Lawler, M.; Smith, James N.; Takahama, S.; Ruggeri, G.; Koss, A.; Olson, K.; Baumann, K.; Weber, R. J.; Nenes, A.; Guo, H.; Edgerton, Eric S.; Porcelli, L.; Brune, W. H.; Goldstein, Allen H.; Lee, S.-H

    2014-11-19

    We report ambient measurements of amines and ammonia with a fast response chemical ionization mass spectrometer (CIMS) in a Southeastern U.S. forest in Alabama and a moderately polluted Midwestern site during the summer. In the Alabama forest, mostly C3-amines (from pptv to tens of pptv) and ammonia (up to 2 ppbv) were detected on a daily basis. C3-amines and ammonia showed similar diurnal trends and temperature and wind direction dependences, and were not associated with transported CO and SO2 plumes. Consistent with temperature dependences, amine and ammonia in the gas and aerosol phases showed opposite diurnal trends, indicating gas-to-particle partitioning of amines and ammonia. Temperature dependences also imply reversible processes of amines and ammonia evaporation from soil surfaces in daytime and deposition of amines and ammonia to soil surfaces at nighttime. Various amines (C1-C6) at the pptv level were observed in the transported biomass burning plumes, showing that biomass burning can be a substantial source of amines in the Southeast U.S. At the moderately polluted Kent site, higher concentrations of amines (C1-C6, from pptv to tens of pptv) and ammonia (up to 6 ppbv) were detected. Diurnal variations of C1- to C3-amines and ammonia were correlated with the ambient temperature. C4- to C6-amines showed abrupt increases during the nighttime, suggesting that they were emitted from local sources. These abundant amines and ammonia may in part explain the frequent new particle formation events reported from Kent. Lower amine concentrations at the rural forested site highlight the importance of constraining anthropogenic sources of amines.

  5. Scrub typhus in patients reporting with acute febrile illness at a tertiary health care institution in Goa

    OpenAIRE

    Narvencar, Kedareshwar P.S.; Rodrigues, Savio; Nevrekar, Ramnath P.; Dias, Lydia; Dias, Amit; Vaz, Marina; Gomes, E.

    2012-01-01

    Background & objectives: Scrub typhus is one of the differential diagnoses of haemorrhagic fevers especially if associated with jaundice and/or renal failure. Goa State in the western region of India has been witnessing increased incidence of such fevers, therefore, the present study was undertaken to identify whether scrub typhus is the aetiological agent. Methods: Adult patients presenting with undiagnosed febrile illness between June 2009 to October 2010, were evaluated. Testing was done u...

  6. Scrub Typhus with Acute Respiratory Distress Syndrome (ARDS) and its Management in Intensive Care Unit: A Case Report

    OpenAIRE

    Sankuratri, Srinivas; Kalagara, Pavani; Samala, Kartika Balaji; Veledandi, Prabhakar Krishna; Atiketi, Srinadh Babu

    2015-01-01

    Scrub typhus is zoonotic disease caused by Orientia tsutsugamushi (O tsutsugamushi). It is transmitted to humans by the bite of trombiculid mite larvae (chiggers). It is a re-emerging infectious disease in India. Clinical manifestations include fever, headache, anorexia, myalgia, eschar, adenopathy and maculopapular rash. Complications of Scrub typhus develop after first week of illness. Complications include meningoencephalitis, jaundice, myocarditis, ARDS and renal failure. Eschar and rash ...

  7. Reducing ammonia emissions in Europe

    DEFF Research Database (Denmark)

    Jacobsen, Brian H.

    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...... 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 2020 NEC ceiling....

  8. Comparative efficacy of alcohol-based surgical scrubs: the importance of formulation.

    Science.gov (United States)

    Macinga, David R; Edmonds, Sarah L; Campbell, Esther; McCormack, Robert R

    2014-12-01

    Alcohol-based surgical scrubs (ABSSs) are used to prevent surgical site infections. Chlorhexidine gluconate (CHG) often is added to enhance persistent germicidal activity. The aim of this study was to determine the influence of ABSS product formulation on efficacy. We evaluated three commercially available ABSS formulations and one control alcohol formulation according to the surgical scrub methodology specified by the US Food and Drug Administration (FDA). Only one ABSS formulation met FDA efficacy requirements when tested at the manufacturer's recommended dosage. In contrast, two ABSS formulations, one of which contained CHG, failed to meet the FDA acceptance criteria for a 3-log10 reduction on day 5, meaning the formulations did not sufficiently reduce bacteria levels on hands on the fifth day of product application. The data suggest that recommendations to include CHG in ABSS formulations should be reconsidered, and product efficacy, skin tolerability, and user acceptability should be evaluated on a case-by-case basis. PMID:25453683

  9. On the phylogenetic position of the scrub-birds (Passeriformes: Menurae: Atrichornithidae) of Australia

    Science.gov (United States)

    Chesser, R.T.; ten, Have J.

    2007-01-01

    Evolutionary relationships of the scrub-birds Atrichornis were investigated using complete sequences of the recombination-activating gene RAG-1 and the proto-oncogene c-mos for two individuals of the noisy scrub-bird Atrichornis clamosus. Phylogenetic analysis revealed that Atrichornis was sister to the genus Menura (the lyrebirds) and that these two genera (the Menurae) were sister to the rest of the oscine passerines. A sister relationship between Atrichornis and Menura supports the traditional view, based on morphology and DNA hybridization, that these taxa are closely related. Similarly, a sister relationship with the remaining oscine passerines agrees with the morphological distinctiveness of Atrichornis and Menura, although this result contradicts conclusions based on DNA hybridization studies. Although Atrichornis is very well known morphologically, previous conclusions regarding its relationships were hampered by a lack of comparative knowledge of other passerines, making concurrence of the sequence data of particular significance. ?? Dt. Ornithologen-Gesellschaft e.V. 2007.

  10. Efficacy of plant essential oils for the repellents against chiggers (Leptotrombidium imphalum) vector of scrub typhus.

    Science.gov (United States)

    Rodkvamtook, Wuttikon; Prasartvit, Anchana; Jatisatienr, Chaiwat; Jatisatienr, Araya; Gaywee, Jariyanart; Eamsobhana, Praphathip

    2012-05-01

    Scrub typhus caused by the Orientia tsutsugamushi. Rodents, particularly rats, serve as principal reservoir hosts. Infection in man is transmitted by the, chigger bite. Repellents provide an effective agent of protecting individuals from chigger. In the present study 6 plant essential oils were tested for evaluation of their repellent activity against the chigger, Leptotrombidium imphalum. The results showed that Clove oil was significantly more effective than others with ED50 and EC50 of 0.420 mg and 2.3%, followed by Zingiber oil (8.458 mg and 42.3%), Vetiver oil (19.582 mg and 97.9%), Turmeric oil (24.343 mg and 121.7%), Orange oil (27.310 mg and 136.6%) and Boesenbergia oil (30.486 mg and 152.4%). These results suggested that Clove oil was the most efficient repellent against chigger which is the vector for scrub typhus. PMID:22934454

  11. 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.

  12. 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.

  13. Etiologies of acute undifferentiated fever and clinical prediction of scrub typhus in a non-tropical endemic area.

    Science.gov (United States)

    Jung, Ho-Chul; Chon, Sung-Bin; Oh, Won Sup; Lee, Dong-Hyun; Lee, Ho-Jin

    2015-02-01

    Scrub typhus usually presents as acute undifferentiated fever. This cross-sectional study included adult patients presenting with acute undifferentiated fever defined as any febrile illness for ≤ 14 days without evidence of localized infection. Scrub typhus cases were defined by an antibody titer of a ≥ fourfold increase in paired sera, a ≥ 1:160 in a single serum using indirect immunofluorescence assay, or a positive result of the immunochromatographic test. Multiple regression analysis identified predictors associated with scrub typhus to develop a prediction rule. Of 250 cases with known etiology of acute undifferentiated fever, influenza (28.0%), hepatitis A (25.2%), and scrub typhus (16.4%) were major causes. A prediction rule for identifying suspected cases of scrub typhus consisted of age ≥ 65 years (two points), recent fieldwork/outdoor activities (one point), onset of illness during an outbreak period (two points), myalgia (one point), and eschar (two points). The c statistic was 0.977 (95% confidence interval = 0.960-0.994). At a cutoff value ≥ 4, the sensitivity and specificity were 92.7% (79.0-98.1%) and 90.9% (86.0-94.3%), respectively. Scrub typhus, the third leading cause of acute undifferentiated fever in our region, can be identified early using the prediction rule. PMID:25448236

  14. A STUDY OF CLINICAL AND EPIDEMIOLOGICAL CHARACTERISTICS OF SCRUB TYPHUS IN TERTIARY CARE HOSPITAL IN ANDHRA PRADESH

    Directory of Open Access Journals (Sweden)

    Ramachandra Rao

    2015-04-01

    Full Text Available Scrub typhus is a mite borne infectious disease caused by orientia tsutsugamushi. Scrub typhus is geographically confined to Asia pacific region. In India cases of scrub typhus are reported during world war – II from Assam and west Bengal, later the presence of this disease was found throughout I ndia, f rom S outh India isolated case reports are seen from Kerala, Tamilnadu and Karnataka. Recently there are isolated case reports from Andhra Pradesh but no documented case studies to our knowledge. It is possible that it exists in other states as well but goes unnoticed as physicians fail to recognize it, many physicians may be treating their patients with scrubtyphus without considering in their differential diagnosis as it responds to commonly used antibiotics. Recently we have been seeing a series of cases of scrub typhus in our hospital, so a prospective study has been done to study the clinical and epidemiological characters of this disease. Here we report a total of 56 cases of scrub typhus which were tested positive for IgM scrubtyphus by ELISA method. Through this study we hope to make physicians aware of this disease which is probably more widespread than considered and easily manageable if it is diagnosed early and prompt treatment is initiated. KEYWORDS: Scrub Typhus - Eschar.

  15. Patient attitudes toward the use of surgical scrubs in a military hospital clinic

    OpenAIRE

    Lund, Jon D; Rohrer, James E; Goldfarb, Susana

    2008-01-01

    Objective To determine whether obstetrics and gynecology (ob/gyn) patients in a large military teaching hospital have a negative attitude toward the wearing of surgical scrubs by ob/gyn providers. Methods A convenience sample questionnaire on patient preferences, including two questions relating independently to military and civilian staff attire, was offered to clinic patients over a 2 month period. Univariate and multiple logistic regression analyses were used to identify patient groups les...

  16. Bacterial abundance on hands and its implications for clinical trials of surgical scrubs.

    OpenAIRE

    Spradlin, C T

    1980-01-01

    The numbers of bacteria on the hands of 157 subjects volunteering for a clinical trial of a surgical scrub preparation were evaluated statistically. Differences among the volunteers with respect to day-to-day variability in bacterial counts were the most important source of variation in these counts. Generally, more bacteria were found on the left hand than on the right. The experimental plan, proposed by the U.S. Food and Drug Administration, contained criteria for acceptability of subjects ...

  17. Season-dependent and independent responses of Mediterranean scrub to light conditions.

    Science.gov (United States)

    Zunzunegui, María; Díaz-Barradas, Mari Cruz; Jáuregui, Juan; Rodríguez, Herminia; Álvarez-Cansino, Leonor

    2016-05-01

    Semi-arid plant species cope with excess of solar radiation with morphological and physiological adaptations that assure their survival when other abiotic stressors interact. At the leaf level, sun and shade plants may differ in the set of traits that regulate environmental stressors. Here, we evaluated if leaf-level physiological seasonal response of Mediterranean scrub species (Myrtus communis, Halimium halimifolium, Rosmarinus officinalis, and Cistus salvifolius) depended on light availability conditions. We aimed to determine which of these responses prevailed independently of the marked seasonality of Mediterranean climate, to define a leaf-level strategy in the scrub community. Thirty six leaf response variables - involving gas exchange, water status, photosystem II photochemical efficiency, photosynthetic pigments and leaf structure - were seasonally measured in sun exposed and shaded plants under field conditions. Physiological responses showed a common pattern throughout the year, in spite of the marked seasonality of the Mediterranean climate and of species-specific differences in the response to light intensity. Variables related to light use, CO2 assimilation, leaf pigment content, and LMA (leaf mass area) presented differences that were consistent throughout the year, although autumn was the season with greater contrast between sun and shade plants. Our data suggest that in Mediterranean scrub shade plants the lutein pool could have an important role in the photoprotection of the photosynthetic tissues. There was a negative linear correlation between the ratio lutein/total chlorophylls and the majority of leaf level variables. The combined effect of abiotic stress factors (light and drought or light and cold) was variable-specific, in some cases enhancing differences between sun and shade plants, while in others leading to unified strategies in all scrub species. PMID:26913795

  18. Optimal Cutoff Titers for Indirect Immunofluorescence Assay for Diagnosis of Scrub Typhus

    OpenAIRE

    Lim, Cherry; Blacksell, Stuart D; Laongnualpanich, Achara; Kantipong, Pacharee; Day, Nicholas P. J.; Paris, Daniel H.; Limmathurotsakul, Direk

    2015-01-01

    We determined the optimal cutoff titers in admission and convalescent-phase samples for scrub typhus indirect immunofluorescence assay using Bayesian latent class models. Cutoff titers of ≥1:3,200 in an admission sample or of a ≥4-fold rise to ≥1:3,200 in a convalescent-phase sample provided the highest accuracy (sensitivity, 81.6%; specificity, 100%).

  19. Emerging scrub typhus infection in the northern region of Sri Lanka

    OpenAIRE

    Pradeepan, Jebananthy Anandaselvam; Ketheesan, Natkunam; Murugananthan, Kalamathy

    2014-01-01

    Background There is an increasing trend in rickettsioses or typhus fevers in the island of Sri Lanka. The seroepidemiological mapping previously published did not include the northern region of the island. This study was conducted to demonstrate the presence of scrub typhus (ST) and to characterise the clinical presentation of ST in this region. Findings Serum samples from patients (n = 64) with clinical symptoms suspected of typhus fever following exclusion of other common febrile illnesses ...

  20. Determination of Cutoff of ELISA and Immunofluorescence Assay for Scrub Typhus

    Science.gov (United States)

    Gupta, Nitin; Chaudhry, Rama; Thakur, Chandan Kumar

    2016-01-01

    Background: The most common method employed for diagnosis of scrub typhus is serology. It is widely known that demonstration of ≥4-fold rise in titers of antibody in paired sera is required for diagnosis. However, for guidance of initial treatment, there is a need for rapid diagnosis at the time of admission. Therefore, there is a need for standardized region specific cutoff titers at the time of admission. Materials and Methods: A total of 258 patients of all age groups with clinically suspected scrub typhus over a period of 24 months (October 2013-October 2015) were enrolled. Serum samples of these patients were subjected to immunofluorescent antibody (IFA) for immunoglobulin M (IgM) (Fuller Labs, USA) with dilutions of 1:64, 1:128, 1:256, and 1:512. Serum samples of all 258 patients were subjected to IgM ELISA (Inbios Inc., USA). Any patient with response to antibiotics within 48 h accompanied by either presence of an eschar or positivity by polymerase chain reaction was taken as positive. Receiver operating characteristic (ROC) curve was drawn to generate cutoff for these tests. Results: A total of 20 patients were diagnosed as cases of scrub typhus. The ROC curve analysis revealed a cutoff optical density value of 0.87 with sensitivity and specificity of 100% and 94.12%, respectively. ROC curve analysis of IFA revealed sensitivity and specificity of 100% and 93.5%, respectively at 1:64 dilution. Conclusion: Considering cost constraints, centers in and around New Delhi region can use the cutoffs we determined for the diagnosis of scrub typhus.

  1. Q Fever, Scrub Typhus, and Rickettsial Diseases in Children, Kenya, 2011–2012

    Science.gov (United States)

    Farris, Christina M.; Odhiambo, Antony; Jiang, Ju; Laktabai, Jeremiah; Armstrong, Janice; Holland, Thomas; Richards, Allen L.; O’Meara, Wendy P.

    2016-01-01

    To increase knowledge of undifferentiated fevers in Kenya, we tested paired serum samples from febrile children in western Kenya for antibodies against pathogens increasingly recognized to cause febrile illness in Africa. Of patients assessed, 8.9%, 22.4%, 1.1%, and 3.6% had enhanced seroreactivity to Coxiella burnetii, spotted fever group rickettsiae, typhus group rickettsiae, and scrub typhus group orientiae, respectively. PMID:27088502

  2. 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

  3. [Improving the quality of work life. Awkward and strained postures among scrub nurses].

    Science.gov (United States)

    Martínez, María Ruzafa; Madrigal de Torres, Fernando; Ruíz García, M Jesús; Salinas Marín, Rufina

    2003-04-01

    Latest statistics show worrying figures about labour accidents and illnesses in surgical nursery, due to the lack of preventing measures or unsuitable working conditions. Actually the duties of a scrub nurse bring an important static physical burden and the fulfilment of reiterative movements, as well as environmental conditions that may raise the provability of the development of skeletal muscular diseases in a medium-long time. In order to monitor the correct accomplishment of preventing rules related to working postures and the handling of heavy loads and identify risk factors that may lead to these disorders and asses symptoms related to inadequate positions and/or heavy efforts, a descriptive quantitative study was carried out over 24 theatre nurses from 2 hospitals in Murcia. According to the gathered information, analysed with the statistic program SPSS, the adopted measures to avoid risks are inadequate and insufficient. The inquired population adopt unsuitable postures in a high proportion moreover, what let us establish a significant correlation with the obtained information referred to the posture adopted. As a result, we cannot any longer state that scrub nurses are undergoing the established preventive rules in order to avoid those symptoms associated to the kind of job they carry out. To sum up we believe as very necessary to improve the scrub nurses' quality of work life, the removal of risk factors and the supply of suitable instrumental, drawing up a protocol of safety and working behaviours as well as offering seminars to teach that protocol. PMID:14502935

  4. Reaction Mechanism for Ammonia Activation in the Selective Ammoxidation of Propene on Bismuth Molybdates

    OpenAIRE

    Pudar, Sanja; Goddard, William A.

    2015-01-01

    In this paper, we report quantum mechanical studies (using the B3LYP flavor of density functional theory) for various pathways of ammonia activation on bismuth molybdates, a process required for ammoxidation of propene to acrylonitrile. Using a Mo_3O_9 cluster to model the bulk surface, we examined the activation of ammonia by both fully oxidized (MoIV) and reduced (Mo^(IV)) molybdenum sites. Our results show that ammonia activation does not take place on the fully oxidized Mo(VI) sites. Here...

  5. 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...

  6. Ammonia Solubility in High Concentration Salt Solutions

    Energy Technology Data Exchange (ETDEWEB)

    HEDENGREN, D.C.

    2000-02-01

    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.

  7. Evaluation of ammonia emissions from broiler litter

    Science.gov (United States)

    Ammonia emissions from poultry litter results in air pollution and can cause high levels of ammonia in poultry houses, which negatively impacts bird performance. The objectives of this study were to: (1) conduct a nitrogen (N) mass balance in broiler houses by measuring the N inputs (bedding, chick...

  8. 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

  9. 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...

  10. Ammonia and urea permeability of mammalian aquaporins

    DEFF Research Database (Denmark)

    Litman, Thomas; Søgaard, Rikke; Zeuthen, Thomas

    2009-01-01

    /arginine region, and an exclusively water-permeable aquaporin can be transformed into an ammonia-permeable aquaporin by single point mutations in this region. The ammonia-permeable aquaporins fall into two groups: those that are permeable (AQP3, 7, 9, 10) and those that are impermeable (AQP8) to glycerol. The two......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...... significant at alkaline pH. It is debated whether the H(+) ion passes via the aquaporin or by some external route; the investigation of this problem requires the aquaporin-expressing cell to be voltage-clamped. The ammonia-permeable aquaporins differ from other aquaporins by having a less restrictive aromatic...

  11. 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.

  12. 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...

  13. 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.

  14. 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

  15. Catalytic synthesis of ammonia using vibrationally excited nitrogen molecules

    DEFF Research Database (Denmark)

    Hansen, Flemming Yssing; Henriksen, Niels Engholm; Billing, Gert D.; Guldberg, Annette

    The dissociation of nitrogen is the rate-limiting step in the catalytic synthesis of ammonia. Theoretical calculations have shown that the dissociative sticking probability of molecular nitrogen on catalytic active metal surfaces is enhanced by orders of magnitude when the molecules are vibration......The dissociation of nitrogen is the rate-limiting step in the catalytic synthesis of ammonia. Theoretical calculations have shown that the dissociative sticking probability of molecular nitrogen on catalytic active metal surfaces is enhanced by orders of magnitude when the molecules are...... vibrationally excited to states with quantum numbers 3-10. The rate and equilibrium constants for the process using vibrationally excited nitrogen molecules are calculated and expressions for the reaction rates are derived. A comparison with the ordinary process, where the nitrogen molecules are in the...

  16. Prevention of airborne disposal from staff in the O.R. reducing the risk of infection : what are the benefits of using clean air suits or scrub suits?

    OpenAIRE

    Abreu, Maria José Araújo Marques

    2012-01-01

    Experts in infection control are often asked about issues related to the use of scrubs and clean air suits in the operating room (OR). So, what are clean air suits and scrub suits? This article seeks to highlight the most relevant information of this products and try to define the benefits of using them for preventing airborne disposal from the surgical staff, reducing the risk of infection. No scientific data support the practice of using scrub suits as a means for preventing transmis...

  17. A gender based comparative analysis of laboratory investigations in scrub typhus patients at tertiary care teaching hospital of Southern Rajasthan, India

    OpenAIRE

    Syed Javed; Sanjay Paliwal; Shubhakaran Sharma; Savita Choudhary

    2016-01-01

    Background: Scrub typhus is an acute febrile infectious disease which is common in both male and female patients. This study was done to compare the laboratory tests of the scrub typhus patients with reference to sex. Methods: This retrospectively study was carried out in diagnosed scrub typhus patients who were admitted to intensive care unit of a tertiary care teaching hospital of Southern Rajasthan. Diagnosis was done by testing for specific IgM antibodies against Orientia tsutsugamushi...

  18. 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.

  19. 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.

  20. 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.

  1. 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 ...

  2. 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...

  3. 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...

  4. Performance studies on hydrofluoric acid fumes scrubbing systems

    International Nuclear Information System (INIS)

    Uranium hexafluoride gas is a major process medium for the production of nuclear fuels. Different types of scrubbers suitable for disposal of exhaust gases containing low concentration of HF/UF6 contaminants, treatment of contaminated air from the working environment of a plant and bulk quantity of HF/UF6 from storage vessels are described

  5. 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....... The effect of acidification on emissions of H2S differed between experiments. Implications of slurry acidification for subsequent field application, including N and S availability, and soil pH, are discussed....... rates were generally high. It was concluded that the contribution from floors to NH3 emissions was <50%. There was some evidence for reduced CH4 emissions from acidified slurry, but CH4 emissions were generally low and apparently dominated by enteric fermentation. No effect on N2O emissions was observed...

  6. 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.

  7. Electrochemical Synthesis of Ammonia in Solid Electrolyte Cells

    Directory of Open Access Journals (Sweden)

    MichaelStoukides

    2014-01-01

    Full Text Available Developed in the early 1900's, the “Haber-Bosch” synthesis is the dominant NH3 synthesis process. Parallel to catalyst optimization, current research efforts are also focused on the investigation of new methods for ammonia synthesis, including the electrochemical synthesis with the use of solid electrolyte cells. Since the first report on Solid State Ammonia Synthesis (SSAS, more than 30 solid electrolyte materials were tested and at least 15 catalysts were used as working electrodes. Thus far, the highest rate of ammonia formation reported is 1.13×10−8 mol s−1 cm−2, obtained at 80°C with a Nafion solid electrolyte and a mixed oxide, SmFe0.7Cu0.1Ni0.2O3, cathode. At high temperatures (>500oC the maximum rate was 9.5*10-9 mol s−1 cm−2 using Ce0.8Y0.2O2-δ -[Ca3(PO42 -K3PO4] as electrolyte and Ag-Pd as cathode. In this paper, the advantages and the disadvantages of SSAS vs the conventional process and the requirements that must be met in order to promote the electrochemical process into an industrial level, are discussed.

  8. 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).

  9. 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.

  10. 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.

  11. 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.

  12. Lyoluminescence of luminol in aqueous ammonia

    International Nuclear Information System (INIS)

    The emission spectrum of lyoluminescence of luminol in aqueous ammonia was recorded on a Fuess spectrograph. A continuous emission band from 370 to 600 nm, on resolution, showed three-banded emission with peaks at 413, 463 and 545 nm. The resolved fluorescence spectrum of luminol in ammonia showed two peaks, at 407 and 446 nm. The fluorescence lifetime of luminol in aqueous ammonia solution is 0.7 ns. The lyoluminescence emission bands are explained on the basis of the reactions of colour centres with luminol during the dissolution of irradiated NaCl crystals in an aqueous ammoniated solution of luminol. (author)

  13. Studies of the kinetics of two parallel reactions: ammonia decomposition and nitriding of iron catalyst.

    Science.gov (United States)

    Arabczyk, Walerian; Pelka, Rafat

    2009-01-15

    The reaction of ammonia decomposition and nitriding reaction as an example of the parallel reactions were studied. A surface reaction was assumed as the rate limiting step. The experiments were carried out in the range of temperatures from 623 to 723 K. Mixtures of different iron nitrides (gamma'-Fe(4)N, epsilon-Fe(3-2)N) were obtained. Differential tubular reactor with thermogravimetric (TG) measurement and analysis of the gas phase composition in the reaction volume was used. Reacting gases flowing through the reactor were mixed. Effective reactor volume was determined. The rate constants for ammonia decomposition and ammonia adsorption process at critical point between alpha-Fe and gamma'-Fe(4)N phases were estimated. The number of collisions and the sticking coefficient of ammonia over alpha-Fe phase were also assessed. PMID:19086865

  14. 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.

  15. 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

  16. 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.

  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. Comparative study on ammonia oxidation over Ni-based cermet anodes for solid oxide fuel cells

    Science.gov (United States)

    Molouk, Ahmed Fathi Salem; Yang, Jun; Okanishi, Takeou; Muroyama, Hiroki; Matsui, Toshiaki; Eguchi, Koichi

    2016-02-01

    In the current work, we investigate the performance of solid oxide fuel cells (SOFCs) with Ni‒yttria-stabilized zirconia (Ni-YSZ) and Ni‒gadolinia-dope ceria (Ni-GDC) cermet anodes fueled with H2 or NH3 in terms of the catalytic activity of ammonia decomposition. The cermet of Ni-GDC shows higher catalytic activity for ammonia decomposition than Ni-YSZ. In response to this, the performance of direct NH3-fueled SOFC improved by using Ni-GDC anode. Moreover, we observe further enhancement in the cell performance and the catalytic activity for ammonia decomposition with applying Ni-GDC anode synthesised by the glycine-nitrate combustion process. These results reveal that the high performance of Ni-GDC anode for the direct NH3-fueled SOFC results from its mixed ionic-electronic conductivity as well as high catalytic activity for ammonia decomposition.

  19. 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...... impacts. It was proved that at pH>9, the leaching of DOC increased significantly in the presence of high concentrations of ammonia (≥1357 mg·L-1), but there was little effect when the ammonia level in eluates was not higher than 537 mg·L-1. At pH12, for Cd, Cu, Ni and Zn, their leaching species were...

  20. The Correlation of Endoscopic Findings and Clinical Features in Korean Patients with Scrub Typhus: A Cohort Study.

    Directory of Open Access Journals (Sweden)

    Jun Lee

    Full Text Available Scrub typhus is an infectious disease caused by Orientia tsutsugamushi-induced systemic vasculitis, but the involvement of the gastrointestinal tract and the endoscopic findings associated with scrub typhus are not well understood. We performed a prospective study and recommend performing esophagogastroduodenoscopy (EGD for all possible scrub typhus patients, regardless of gastrointestinal symptoms. Gastrointestinal symptoms, endoscopic findings and clinical severity based on organ involvement and ICU admission were analyzed. Gastrointestinal symptoms occurred in up to 76.4% of scrub typhus patients. The major endoscopic findings were ulcers (43/127, 33.9%. Interestingly, 7.1% (9/127 of the patients presented with esophageal candidiasis. There was no correlation between the presence or absence of gastrointestinal symptoms and the endoscopic grade (P = 0.995. However, there was a positive correlation between the clinical severity and the endoscopic findings (P = 0.001. Sixty-three percent of the patients presented with erosion or ulcers on prospectively performed endoscopic evaluations, irrespective of gastrointestinal symptoms. Gastrointestinal symptoms did not reflect the need for endoscopy. Scrub typhus patients could have significant endoscopic abnormalities even in the absence of gastrointestinal symptoms.

  1. Clinical and Epidemiological Characteristics of Scrub Typhus and Murine Typhus among Hospitalized Patients with Acute Undifferentiated Fever in Northern Vietnam.

    Science.gov (United States)

    Hamaguchi, Sugihiro; Cuong, Ngo Chi; Tra, Doan Thu; Doan, Yen Hai; Shimizu, Kenta; Tuan, Nguyen Quang; Yoshida, Lay-Myint; Mai, Le Quynh; Duc-Anh, Dang; Ando, Shuji; Arikawa, Jiro; Parry, Christopher M; Ariyoshi, Koya; Thuy, Pham Thanh

    2015-05-01

    A descriptive study on rickettsiosis was conducted at the largest referral hospital in Hanoi, Vietnam, to identify epidemiological and clinical characteristics of specific rickettsiosis. Between March 2001 and February 2003, we enrolled 579 patients with acute undifferentiated fever (AUF), excluding patients with malaria, dengue fever, and typhoid fever, and serologically tested for Orientia tsutsugamushi and Rickettsia typhi. Of the patients, 237 (40.9%) and 193 (33.3%) had scrub and murine typhus, respectively, and 149 (25.7%) had neither of them (non-scrub and murine typhus [non-ST/MT]). The proportion of murine typhus was highest among patients living in Hanoi whereas that of scrub typhus was highest in national or regional border areas. The presence of an eschar, dyspnea, hypotension, and lymphadenopathy was significantly associated with a diagnosis of scrub typhus (OR = 46.56, 10.90, 9.01, and 7.92, respectively). Patients with murine typhus were less likely to have these findings but more likely to have myalgia, rash, and relative bradycardia (OR = 1.60, 1.56, and 1.45, respectively). Scrub typhus and murine typhus were shown to be common causes of AUF in northern Vietnam although the occurrence of spotted fever group rickettsiae was not determined. Clinical and epidemiological information may help local clinicians make clinical diagnosis of specific rickettsioses in a resource-limited setting. PMID:25778504

  2. The Clearing: Heidegger’s Lichtung and The Big Scrub

    Directory of Open Access Journals (Sweden)

    Rob Garbutt

    2010-02-01

    Full Text Available Clearings make settlement possible. Whether on a small scale using an axe and other hand implements to make way for a dwelling and a garden, or on a large scale with a chain strung between two D9 bulldozers in preparation for a major agribusiness development, the process of clearing creates spaces for installing something new. This paper uses the idea of (the clearing, as practice, process, outcome and metaphor, to examine the installation of the locals in a settler society. Using Lismore on the far-north coast of New South Wales, Australia, as a case example, the particular work of clearing that is discussed here is a practice that enables a form of colonisation and settlement that distances itself from its history of migration. This is a history of settler locals who were 'always here', and a colonial form of clearing clears the land and the mind of troubling pasts and of troubling presences. For the locals within a place, then, clearing manages and simplifies a complex set of social and material relations, histories and identities. Using Anthony Appiah's concept the 'space clearing gesture', the paper concludes with a reflection on the space in which the idea of "the clearing" and this paper appears. Do places, in this instance rural places, provide a type of clearing in which certain ideas might appear that may not appear elsewhere? If situatedness matters then the diversity of places where thinking is done is important for our ecology of thought, and in connection with this, perhaps what 'rural cultural studies' does is clear a particular type of space for thinking.

  3. The Clearing : Heidegger’s Lichtung and the big scrub

    Directory of Open Access Journals (Sweden)

    Garbutt, Rob

    2010-01-01

    Full Text Available Clearings make settlement possible. Whether on a small scale using an axe and other hand implements to make way for a dwelling and a garden, or on a large scale with a chain strung between two D9 bulldozers in preparation for a major agribusiness development, the process of clearing creates spaces for installing something new. This paper uses the idea of (the clearing, as practice, process, outcome and metaphor, to examine the installation of the locals in a settler society. Using Lismore on the far-north coast of New South Wales, Australia, as a case example, the particular work of clearing that is discussed here is a practice that enables a form of colonisation and settlement that distances itself from its history of migration. This is a history of settler locals who were 'always here', and a colonial form of clearing clears the land and the mind of troubling pasts and of troubling presences. For the locals within a place, then, clearing manages and simplifies a complex set of social and material relations, histories and identities.Using Anthony Appiah's concept the 'space clearing gesture', the paper concludes with a reflection on the space in which the idea of "the clearing" and this paper appears. Do places, in this instance rural places, provide a type of clearing in which certain ideas might appear that may not appear elsewhere? If situatedness matters then the diversity of places where thinking is done is important for our ecology of thought, and in connection with this, perhaps what 'rural cultural studies' does is clear a particular type of space for thinking.

  4. Surface Modifications of Polyester Films by Ammonia Plasma

    Science.gov (United States)

    Narushima, Kazuo; Yamashita, Nanami; Fukuoka, Megumi; Inagaki, Norihiro; Isono, Yoshihiro; Islam, Mohammed Rafiqul

    2007-07-01

    Effects of treatment using ammonia plasma on poly(lactic acid) (PLA), poly(ethylene terephthalate) (PET), and liquid-crystal polymer (LCP) were investigated to elucidate differences related to polymer structures and the mode of introduction of nitrogen functional groups onto the polyester surfaces. Nitrogen functional groups were introduced into PET and LCP, but were not introduced into PLA. Those results indicate reductions in the contact angle for PET and LCP. No decrease in the contact angle was observed for PLA. Reasons for differences in attachment of nitrogen functional groups by ammonia plasma processing on polyester surfaces were discussed. The respective actions of active species were investigated for radicals, electrons, and ions in plasma.

  5. 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.

  6. Thin boron nitride nanotubes formed during annealing in ammonia gas

    International Nuclear Information System (INIS)

    Full text: We present a mechano-thermal process to synthesis thin boron nitride nanotubes of diameter around 7 nanometers. They were produced by mechanical milling of amorphous boron powder at ambient temperature, followed by thermal annealing in ammonia gas. High energy ball milling creates a precursor containing a high density of nanocrystalline BN seeds and fine particles of metal catalyst. Nanotubes grow out from the milled boron powder during subsequent annealing. The novelty of this approach lies in the formation of the thin BN nanotubes by annealing in ammonia gas instead of nitrogen gas. The boron nitride nanotubes produced have a well-defined crystalline structure and there is no iron within them. If nitrogen gas is used, thicker nanotubes of diameter in the range of 20-100 nm were obtained and iron was more likely to be found inside the nanotubes. Copyright (2005) Australian Institute of Physics

  7. Catalytic synthesis of ammonia-a "never-ending story"?

    Science.gov (United States)

    Schlögl, Robert

    2003-05-01

    Nitrogen atoms are essential for the function of biological molecules and thus are and important component of fertilizers and medicaments. Bonds to nitrogen also find nonbiological uses in dyes, explosives, and resins. The synthesis of all these materials requires ammonia as an activated nitrogen building block. This situation is true for natural processes and the chemical industry. Knowledge of the various techniques for the preparation of ammonia is thus of fundamental importance for chemistry. The Haber-Bosch synthesis was the first heterogeneous catalytic system employed in the chemical industry and is still in use today. Understanding the mechanism and the translation of the knowledge into technical perfection has become a fundamental criterion for scientific development in catalysis research. PMID:12746811

  8. 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.

  9. Kinetics and thermodynamics of Si(111) surface nitridation in ammonia

    Science.gov (United States)

    Mansurov, Vladimir G.; Malin, Timur V.; Galitsyn, Yurij G.; Shklyaev, Alexander A.; Zhuravlev, Konstantin S.

    2016-05-01

    Kinetics and thermodynamics of Si(111) surface nitridation under an ammonia flux at different substrate temperatures are investigated by reflection high-energy electron diffraction. Two different stages of the nitridation process were revealed. The initial stage is the fast (within few seconds) formation of ordered two-dimensional SiN phase, occuring due to the topmost active surface Si atom (Sisurf) interaction with ammonia molecules. It is followed by the late stage consisting in the slow (within few minutes) amorphous Si3N4 phase formation as a result of the interaction of Si atoms in the lattice site (Siinc) with chemisorbed ammonia molecules. It was found that the ordered SiN phase formation rate decreases, as the temperature increases. The kinetic model of the initial stage was developed, in which the ordered SiN phase formation is the two-dimensional phase transition in the lattice gas with SiN cells. The enthalpy of the active surface Si atom generation on the clean Si(111) surface was estimated to be about 1.5 eV. In contrast, the amorphous Si3N4 phase formation is the normal (thermally activated) chemical process with the first-order kinetics, whose activation energy and pre-exponential factor are 2.4 eV and 108 1/s, respectively.

  10. Adsorption of ammonia on treated stainless steel and polymer surfaces

    Science.gov (United States)

    Vaittinen, O.; Metsälä, M.; Persijn, S.; Vainio, M.; Halonen, L.

    2014-05-01

    Adsorption of dynamically diluted ammonia at part-per-billion to low part-per-million concentrations in dry nitrogen was studied with treated and non-treated stainless steel and polymer test tubes. The treatments included electropolishing and two types of coatings based on amorphous silicon. Cavity ring-down spectroscopy with an external cavity diode laser operating in the near-infrared wavelength range was used to monitor the adsorption process in real time in continuous-flow conditions to obtain quantitative assessment of the adsorptive properties of the studied surfaces. The investigated polymers were all less adsorptive than any of the treated or non-treated stainless steel surfaces. Some of the commercial coatings reduced the adsorption loss of stainless steel by a factor of ten or more. Polyvinylidene fluoride was found to be superior (less adsorption) to the four other studied polymer coatings. The number of adsorbed ammonia molecules per surface area obtained at different ammonia gas phase concentrations was modeled with Langmuir and Freundlich isotherms. The time behavior of the adsorption-desorption process occurring in the time scale of seconds and minutes was simulated with a simple kinetic model.

  11. Energy efficiency improvements in ammonia production--perspectives and uncertainties

    International Nuclear Information System (INIS)

    The paper discusses the energy consumption and energy saving potential for a major energy-intensive product in the chemical industry-ammonia, based on technologies currently in use and possible process improvements. The paper consists of four parts. In the first part, mainly references to various ammonia production technologies are given. Energy consumption, emissions and saving potentials are discussed in the second part. Thereby, the situation in Europe, the US and India is highlighted and various data sources are compared. In the third part of the paper, a novel approach for modeling energy efficiency improvements is described that accounts for uncertainties and unobserved heterogeneity in the production processes. Besides new investments, revamping investments are also included in the modeling and the development of the production stock is accounted for. Finally, in the fourth part, this approach is applied to the modeling of energy efficiency improvements and CO2 emission reductions in ammonia production. Thereby, considerable improvements in specific energy use and CO2 emissions are found in the reference scenario, yet under the assumption of high oil and gas prices, a partial switch to coal based technologies is expected which lowers notably the CO2 efficiency. Introduction of a CO2 penalty under a certificate trading or other regime is on contrary found to foster energy efficiency and the use of low carbon technologies

  12. Autotrophic ammonia removal from landfill leachate in anaerobic membrane bioreactor.

    Science.gov (United States)

    Suneethi, S; Joseph, Kurian

    2013-01-01

    Anaerobic ammonium oxidation (ANAMMOX) process, an advanced biological nitrogen removal, removes ammonia using nitrite as the electron acceptor without oxygen. In this paper, ANAMMOX process was adopted for removing NH4+-N from landfill leachate having low COD using anaerobic membrane bioreactor (AnMBR). The AnMBR was optimized for nitrogen loading rate (NLR) varying from 0.025 to 5 kg NH4+-N/m3/d with hydraulic retention time (HRT) ranging from 1 to 3d. NH4+-N removal efficacy of 85.13 +/- 9.67% with the mean nitrogen removal rate of 5.54 +/- 0.63 kg NH4+-N/m3/d was achieved with NLR of 6.51 +/- 0.20kg NH4+-N/m3/d at 1.5 d HRT. The nitrogen transformation intermediates in the form of hydrazine (N2H4) and hydroxylamine (NH2OH) were 0.008 +/- 0.005 and 0.006 +/- 0.001 mg/l, respectively, indicating co-existence of aerobic ammonia oxidizers and ANAMMOX. The free ammonia (NH3) and free nitrous acid (HNO2) concentrations were 26.61 +/- 16.54 mg/l and (1.66 +/- 0.95) x 10(-5) mg/l, preventing NO2(-)-N oxidation to NO3(-)-N enabling sustained NH4+-N removal. PMID:24617075

  13. Reduction of the Livestock Ammonia Emission under the Changing Temperature during the Initial Manure Nitrogen Biomineralization

    Directory of Open Access Journals (Sweden)

    Rolandas Bleizgys

    2013-01-01

    Full Text Available Experimental data were applied for the modelling optimal cowshed temperature environment in laboratory test bench by a mass-flow method. The principal factor affecting exponent growth of ammonia emission was increasing air and manure surface temperature. With the manure temperature increasing from 4°C to 30°C, growth in the ammonia emission grew fourfold, that is, from 102 to 430 mg m−2h−1. Especial risk emerges when temperature exceeds 20°C: an increase in temperature of 1°C contributes to the intensity of ammonia emission by 17 mg m−2h−1. The temperatures of air and manure surface as well as those of its layers are important when analysing emission processes from manure. Indeed, it affects the processes occurring on the manure surface, namely, dehydration and crust formation. To reduce ammonia emission from cowshed, it is important to optimize the inner temperature control and to manage air circulation, especially at higher temperatures, preventing the warm ambient air from blowing direct to manure. Decrease in mean annual temperature of 1°C would reduce the annual ammonia emission by some 5.0%. The air temperature range varied between −15°C and 30°C in barns. The highest mean annual temperature (14.6°C and ammonia emission (218 mg m−2h−1 were observed in the semideep cowshed.

  14. Ammonia-nitrogen and phosphates sorption from simulated reclaimed waters by modified clinoptilolite

    International Nuclear Information System (INIS)

    Highlights: ► The salt and thermally modified clinoptilolite can effectively sorb NH3-N and phosphates. ► The phosphorus and nitrogen removal was consistent with Langmuir isotherm model. ► The modified clinoptilolite possesses rapid adsorption and slow balance characteristics. ► The adsorption is more in line with the Elovich adsorption dynamics equation. ► The entropy effect plays the role of the main driving force in the adsorption. - Abstract: This paper presents the investigation of the ammonia-nitrogen and phosphates sorption from simulated reclaimed wastewater by modified clinoptilolite. The results showed that the modified clinoptilolite has a high sorption efficiency and removal performance. The ammonia-nitrogen and phosphates removal rate of the modified clinoptilolite reached to 98.46% and 99.80%, respectively. The surface of modified clinoptilolite became loose and some pores appeared, which enlarged the specific surface area; the contents of Na and Fe increased, and the contents of Ca and Mg decreased. The modified clinoptilolite possesses rapid sorption and slow balance characteristics and ammonia-nitrogen and phosphates sorption is more consistent with the Langmuir isotherm model. The adsorption kinetics of ammonia-nitrogen and phosphates follows the Elovich adsorption dynamics equation, which describes the sorption of ammonia-nitrogen and phosphates in aqueous solution as mainly a chemical sorption. Results from the thermodynamics experiment involving ammonia-nitrogen and phosphates sorption reveal that the process is a spontaneous and endothermic process, and is mainly driven by entropy effect.

  15. Habitat-specific breeder survival of Florida Scrub-Jays: Inferences from multistate models

    Science.gov (United States)

    Breininger, D.R.; Nichols, J.D.; Carter, G.M.; Oddy, D.M.

    2009-01-01

    Quantifying habitat-specific survival and changes in habitat quality within disturbance-prone habitats is critical for understanding population dynamics and variation in fitness, and for managing degraded ecosystems. We used 18 years of color-banding data and multistate capture-recapture models to test whether habitat quality within territories influences survival and detection probability of breeding Florida Scrub-Jays (Aphelocoma coerulescens) and to estimate bird transition probabilities from one territory quality state to another. Our study sites were along central Florida's Atlantic coast and included two of the four largest metapopulations within the species range. We developed Markov models for habitat transitions and compared these to bird transition probabilities. Florida Scrub-Jay detection probabilities ranged from 0.88 in the tall territory state to 0.99 in the optimal state; detection probabilities were intermediate in the short state. Transition probabilities were similar for birds and habitat in grid cells mapped independently of birds. Thus, bird transitions resulted primarily from habitat transitions between states over time and not from bird movement. Survival ranged from 0.71 in the short state to 0.82 in the optimal state, with tall states being intermediate. We conclude that average Florida Scrub-Jay survival will remain at levels that lead to continued population declines because most current habitat quality is only marginally suitable across most of the species range. Improvements in habitat are likely to be slow and difficult because tall states are resistant to change and the optimal state represents an intermediate transitional stage. The multistate modeling approach to quantifying survival and habitat transition probabilities is useful for quantifying habitat transition probabilities and comparing them to bird transition probabilities to test for habitat selection in dynamic environments. ?? 2009 by the Ecological society ot America.

  16. Nutrient enrichment intensifies hurricane impact in scrub mangrove ecosystems in the Indian River Lagoon, Florida, USA.

    Science.gov (United States)

    Feller, Ilka C; Dangremond, Emily M; Devlin, Donna J; Lovelock, Catherine E; Proffitt, C Edward; Rodriguez, Wilfrid

    2015-11-01

    Mangroves are an ecological assemblage of trees and shrubs adapted to grow in intertidal environments along tropical, subtropical, and warm temperate coasts. Despite repeated demonstrations of their ecologic and economic value, multiple stressors including nutrient over-enrichment threaten these and other coastal wetlands globally. These ecosystems will be further stressed if tropical storm intensity and frequency increase in response to global climate changes. These stressors will likely interact, but the outcome of that interaction is uncertain. Here, we examined potential interaction between nutrient over-enrichment and the September 2004 hurricanes. Hurricanes Frances and Jeanne made landfall along Florida's Indian River Lagoon and caused extensive damage to a long-term fertilization experiment in a mangrove forest, which previously revealed that productivity was nitrogen (N) limited across the forest and, in particular, that N enrichment dramatically increased growth rates and aboveground biomass of stunted Avicennia germinans trees in the interior scrub zone. During the hurricanes, these trees experienced significant defoliation with three to four times greater reduction in leaf area index (LAI) than control trees. Over the long-term, the +N scrub trees took four years to recover compared to two years for controls. In the adjacent fringe and transition zones, LAI was reduced by > 70%, but with no differences based on zone or fertilization treatment. Despite continued delayed mortality for at least five years after the storms, LAI in the fringe and transition returned to pre-hurricane conditions in two years. Thus, nutrient over-enrichment of the coastal zone will increase the productivity of scrub mangroves, which dominate much of the mangrove landscape in Florida and the Caribbean; however, that benefit is offset by a decrease in their resistance and resilience to hurricane damage that has the potential to destabilize the system. PMID:27070015

  17. An outbreak investigation of scrub typhus in Western Province, Solomon Islands, 2014

    Directory of Open Access Journals (Sweden)

    Michael Marks

    2016-01-01

    Full Text Available Objective: To identify the etiology and risk factors of undifferentiated fever in a cluster of patients in Western Province, Solomon Islands, May 2014. Methods: An outbreak investigation with a case control study was conducted. A case was defined as an inpatient in one hospital in Western Province, Solomon Islands with high fever (> 38.5 °C and a negative malaria microscopy test admitted between 1 and 31 May 2014. Asymptomatic controls matched with the cases residentially were recruited in a ratio of 1:2. Serum samples from the subjects were tested for rickettsial infections using indirect micro-immunofluorescence assay. Results: Nine cases met the outbreak case definition. All cases were male. An eschar was noted in five cases (55%, and one developed pneumonitis. We did not identify any environmental factors associated with illness. Serum samples of all five follow-up cases (100% had strong-positive IgG responses to scrub typhus. All but one control (10% had a moderate response against scrub typhus. Four controls had low levels of antibodies against spotted fever group rickettsia, and only one had a low-level response to typhus group rickettsia. Discussion: This outbreak represents the first laboratory-confirmed outbreak of scrub typhus in the Western Province of Solomon Islands. The results suggest that rickettsial infections are more common than currently recognized as a cause of an acute febrile illness. A revised clinical case definition for rickettsial infections and treatment guidelines were developed and shared with provincial health staff for better surveillance and response to future outbreaks of a similar kind.

  18. A rapid, sensitive and reliable diagnostic test for scrub typhus in China

    Directory of Open Access Journals (Sweden)

    Zhang Lijuan

    2011-01-01

    Full Text Available Purpose: To evaluate the performances for detection of IgM and IgG antibodies to Orientia. tsutsugamushi (Ot using a gold conjugate-based rapid diagnostic test (RDT. Materials and Methods: The RDT employing mixture recombinant 56-kDa proteins of O. tsutsugamushi and the mIFA assay was performed on 33 patients from Fujian and Yunnan province respectively and 94 positive sera (36 from Hainan province and 58 from Jiangsu province from convalescent stages of the patients with scrub typhus respectively and 82 negative sera from healthy farmers from Anhui province and Beijing City respectively in 2009. A comparison of the RDT and mIFA assay was performed by using the c2 test and the P level of ≤0.05 was considered to be significant. Results: Among these 94 positive sera from convalescent stages of the illness and 82 sera from control farmers, the specificity of RDT was 100% for both IgM and IgG tests. In 33 cases with scrub typhus, 5 cases were positively detected earlier by RDT than by mIFA for the IgM test, and 2 cases were positive for the IgG test. The sensitivities of RDT were 93.9% and 90.9% for IgM and IgG, respectively. Considering IgM and IgG together, the sensitivity was 100%. The geometric mean titre (GMT of IFA and the RDT assay in diluted sera from confirmed cases were 1:37 versus 1:113 respectively (P<0.001 for IgM test and 1:99 versus 1:279 respectively (P<0.016 for IgG. Conclusions: The RDT was more sensitive than the traditional IFA for the early diagnosis of scrub typhus and was particularly suitable for use in rural areas.

  19. Ammonia as a Suitable Fuel for Fuel Cells

    OpenAIRE

    Lan, Rong; Tao, Shanwen

    2014-01-01

    Ammonia, an important basic chemical, is produced at a scale of 150 million tons per year. Half of hydrogen produced in chemical industry is used for ammonia production. Ammonia containing 17.5 wt% hydrogen is an ideal carbon-free fuel for fuel cells. Compared to hydrogen, ammonia has many advantages. In this mini-review, the suitability of ammonia as fuel for fuel cells, the development of different types of fuel cells using ammonia as the fuel and the potential applications of ammonia fuel ...

  20. Ammonia as a suitable fuel for fuel cells

    Directory of Open Access Journals (Sweden)

    ShanwenTao

    2014-08-01

    Full Text Available Ammonia, an important basic chemical, is produced at a scale of 150 million tons per year. Half of hydrogen produced in chemical industry is used for ammonia production. Ammonia containing 17.5wt% hydrogen is an ideal carbon-free fuel for fuel cells. Compared to hydrogen, ammonia has many advantages. In this mini-review, the suitability of ammonia as fuel for fuel cells, the development of different types of fuel cells using ammonia as the fuel and the potential applications of ammonia fuel cells are briefly reviewed.