Laser Diagnostics for Spacecraft Propulsion

Science.gov (United States)

2015-10-13

for public release; distribution unlimited.  AFTC/PA Clearance No.  XXXX 3 Motivation • Many satellite propulsion technologies were developed in the...distribution unlimited.  AFTC/PA Clearance No.  XXXX Propellant Catalyst Bed Decomposition Chamber Thrust Chamber 5 Diode Laser Absorption Spectroscopy Beer...Hydrazine Thruster NH3 Iν(L)Iν0 Ramp t I L DISTRIBUTION A:  Approved for public release; distribution unlimited.  AFTC/PA Clearance No.  XXXX 6 Wavelength

Estimation of Hydrazine Decomposition on Measuring the High-Temperature pH in Hydrazine/ETA Solutions at 553 K

International Nuclear Information System (INIS)

Hwang, Jae Sik; Yeon, Jei Won; Yun, Myung Hee; Song, Kyu Seok; Lee, Sang Ill

2010-01-01

Hydrazine is one of the most excellent oxygen scavengers used in the secondary circuit of nuclear power plants. Furthermore, in some pants, the hydrazine is used as a source of hydrogen required to suppress radiolysis of the coolant water in the primary loop. When hydrazine was exposed in the high temperature and high pressure water, it can be decomposed into the various products such as NH 3 , N 2 , H 2 , and NO 3 ions. As the result, the pH of solution containing hydrazine in the condition of the high temperature and high pressure can be changed by those decomposed products. In the present work, we investigated the decomposition behavior of hydrazine in ETA (ethanol amine) solution. In addition, we measured the high temperature pH at 553 K on the various hydrazine/ETA solutions for confirming the applicability of the yttria stabilized zirconia (YSZ)- based pH electrode in secondary circuit of the nuclear power plants

Tubing For Sampling Hydrazine Vapor

Science.gov (United States)

Travis, Josh; Taffe, Patricia S.; Rose-Pehrsson, Susan L.; Wyatt, Jeffrey R.

1993-01-01

Report evaluates flexible tubing used for transporting such hypergolic vapors as those of hydrazines for quantitative analysis. Describes experiments in which variety of tubing materials, chosen for their known compatibility with hydrazine, flexibility, and resistance to heat.

Preliminary Assessment of Using Gelled and Hybrid Propellant Propulsion for VTOL/SSTO Launch Systems

Science.gov (United States)

Palaszewski, Bryan; OLeary, Robert; Pelaccio, Dennis G.

1998-01-01

A novel, reusable, Vertical-Takeoff-and-Vertical-Takeoff-and-Landing, Single-Stage-to-Orbit (VTOL/SSTO) launch system concept, named AUGMENT-SSTO, is presented in this paper to help quantify the advantages of employing gelled and hybrid propellant propulsion system options for such applications. The launch vehicle system concept considered uses a highly coupled, main high performance liquid oxygen/liquid hydrogen (LO2/LH2) propulsion system, that is used only for launch, while a gelled or hybrid propellant propulsion system auxiliary propulsion system is used during final orbit insertion, major orbit maneuvering, and landing propulsive burn phases of flight. Using a gelled or hybrid propellant propulsion system for major orbit maneuver burns and landing has many advantages over conventional VTOL/SSTO concepts that use LO2/LH2 propulsion system(s) burns for all phases of flight. The applicability of three gelled propellant systems, O2/H2/Al, O2/RP-1/Al, and NTO/MMH/Al, and a state-of-the-art (SOA) hybrid propulsion system are examined in this study. Additionally, this paper addresses the applicability of a high performance gelled O2/H2 propulsion system to perform the primary, as well as the auxiliary propulsion system functions of the vehicle.

Occupational safety considerations with hydrazine fuels

Science.gov (United States)

Clewell, H. J.; Haddad, T. S.; George, M. E.; Mcdougal, J. N.; Andersen, M. E.

1992-01-01

A simple pharmacokinetic model and a specially designed dermal vapor exposure chamber which provides respiratory protection were used to determine the rate of penetration of hydrazine and 1,1-dimethylhydrazine (UDMH) vapor through the skin of rats. Parameters for the pharmacokinetic model were determined from intravenous and inhalation exposure data. The model was then used to estimate the skin permeation coefficient for hydrazine or UDMH vapor from the dermal-vapor exposure data. This analysis indicates that UDMH vapor has a relatively high permeability through skin (0.7 cm/hr), a value somewhat higher than was obtained for hydrazine by the same procedure (0.09 cm/hr). Based on these skin permeability results, a skin-only vapor exposure limit giving protection equivalent to the inhalation Threshold Limit Value (TLV) could be calculated. The current TLV's for UDMH and hydrazine are 0.5 and 0.1 ppm, respectively. The corresponding skin-only TLV equivalents, for personnel wearing respiratory protection, are 32 ppm for UDMH and 48 ppm for hydrazine. Should the proposed lowering to the TLV's for these compounds to 0.01 ppm be adopted, the equivalent skin-only TLV's would become 0.64 ppm for UDMH and 4.8 for hydrazine.

Materials Advance Chemical Propulsion Technology

Science.gov (United States)

2012-01-01

In the future, the Planetary Science Division of NASA's Science Mission Directorate hopes to use better-performing and lower-cost propulsion systems to send rovers, probes, and observers to places like Mars, Jupiter, and Saturn. For such purposes, a new propulsion technology called the Advanced Materials Bipropellant Rocket (AMBR) was developed under NASA's In-Space Propulsion Technology (ISPT) project, located at Glenn Research Center. As an advanced chemical propulsion system, AMBR uses nitrogen tetroxide oxidizer and hydrazine fuel to propel a spacecraft. Based on current research and development efforts, the technology shows great promise for increasing engine operation and engine lifespan, as well as lowering manufacturing costs. In developing AMBR, ISPT has several goals: to decrease the time it takes for a spacecraft to travel to its destination, reduce the cost of making the propulsion system, and lessen the weight of the propulsion system. If goals like these are met, it could result in greater capabilities for in-space science investigations. For example, if the amount (and weight) of propellant required on a spacecraft is reduced, more scientific instruments (and weight) could be added to the spacecraft. To achieve AMBR s maximum potential performance, the engine needed to be capable of operating at extremely high temperatures and pressure. To this end, ISPT required engine chambers made of iridium-coated rhenium (strong, high-temperature metallic elements) that allowed operation at temperatures close to 4,000 F. In addition, ISPT needed an advanced manufacturing technique for better coating methods to increase the strength of the engine chamber without increasing the costs of fabricating the chamber.

A general purpose diagnostic technique for marine diesel engines - Application on the main propulsion and auxiliary diesel units of a marine vessel

International Nuclear Information System (INIS)

Lamaris, V.T.; Hountalas, D.T.

2010-01-01

Diesel engines are widely used in marine applications (i.e. propulsion and auxiliaries) except from a few cases where gas or steam turbines are used. This is the result of their high efficiency, power concentration and reliability compared to other compatible or alternative power sources. The proper and efficient operation of the engines (main engine and diesel generator units) in marine applications is critical, and therefore techniques or systems that determine engine current condition and detect potential faults are extremely important. Furthermore, it is advantageous when such techniques can be applied on different engine configurations and provide reliable results, because on a vessel usually exist diesel engines of different type, i.e. the main propulsion unit is a large low-speed two-stroke diesel engine while the diesel generators are four-stroke medium or high speed engines. In the present work is described and evaluated for the first time the application of an improved diagnostic technique, developed by the authors, on both the main engine and the auxiliary units of a commercial marine vessel. The diagnostic technique is based on a thermodynamic simulation model. The simulation model embedded in the technique has been modified, namely an existing two-zone model is replaced by a multi-zone one. With this modification it is avoided model constant tuning with the operating conditions. This is extremely important for the diagnostic philosophy of the proposed technique. Using data from engine shop tests, the simulation model is calibrated (i.e. model constants are determined) and the engine reference condition is obtained. The simulation model is then used to estimate the current engine condition, using field measurements (i.e. cylinder pressure measurements, periphery data, etc.). From the results it is revealed that the diagnosis method provides detailed information for the operating condition of both engines and the values of parameters that cannot be

A data acquisition and storage system for the ion auxiliary propulsion system cyclic thruster test

Science.gov (United States)

Hamley, John A.

1989-01-01

A nine-track tape drive interfaced to a standard personal computer was used to transport data from a remote test site to the NASA Lewis mainframe computer for analysis. The Cyclic Ground Test of the Ion Auxiliary Propulsion System (IAPS), which successfully achieved its goal of 2557 cycles and 7057 hr of thrusting beam on time generated several megabytes of test data over many months of continuous testing. A flight-like controller and power supply were used to control the thruster and acquire data. Thruster data was converted to RS232 format and transmitted to a personal computer, which stored the raw digital data on the nine-track tape. The tape format was such that with minor modifications, mainframe flight data analysis software could be used to analyze the Cyclic Ground Test data. The personal computer also converted the digital data to engineering units and displayed real time thruster parameters. Hardcopy data was printed at a rate dependent on thruster operating conditions. The tape drive provided a convenient means to transport the data to the mainframe for analysis, and avoided a development effort for new data analysis software for the Cyclic test. This paper describes the data system, interfacing and software requirements.

Treatment for hydrazine-containing waste water solution

Science.gov (United States)

Yade, N.

1986-01-01

The treatment for waste solutions containing hydrazine is presented. The invention attempts oxidation and decomposition of hydrazine in waste water in a simple and effective processing. The method adds activated charcoal to waste solutions containing hydrazine while maintaining a pH value higher than 8, and adding iron salts if necessary. Then, the solution is aerated.

Power processing for electric propulsion

Science.gov (United States)

Finke, R. C.; Herron, B. G.; Gant, G. D.

1975-01-01

The potential of achieving up to 30 per cent more spacecraft payload or 50 per cent more useful operating life by the use of electric propulsion in place of conventional cold gas or hydrazine systems in science, communications, and earth applications spacecraft is a compelling reason to consider the inclusion of electric thruster systems in new spacecraft design. The propulsion requirements of such spacecraft dictate a wide range of thruster power levels and operational lifetimes, which must be matched by lightweight, efficient, and reliable thruster power processing systems. This paper will present electron bombardment ion thruster requirements; review the performance characteristics of present power processing systems; discuss design philosophies and alternatives in areas such as inverter type, arc protection, and control methods; and project future performance potentials for meeting goals in the areas of power processor weight (10 kg/kW), efficiency (approaching 92 per cent), reliability (0.96 for 15,000 hr), and thermal control capability (0.3 to 5 AU).

Space storable propulsion components development

Science.gov (United States)

Hagler, R., Jr.

1982-01-01

The current development status of components to control the flow of propellants (liquid fluorine and hydrazine) in a demonstration space storable propulsion system is discussed. The criteria which determined the designs for the pressure regulator, explosive-actuated valves, propellant shutoff valve, latching solenoid-actuated valve and propellant filter are presented. The test philosophy that was followed during component development is outlined. The results from compatibility demonstrations for reusable connectors, flange seals, and CRES/Ti-6Al4V transition tubes and the evaluations of processes for welding (hand-held TIG, automated TIG, and EB), cleaning for fluorine service, and decontamination after fluorine exposure are described.

Research on anhydrous hydrazine synthesis; Recherche sur la synthese de l'hydrazine anhydre

Energy Technology Data Exchange (ETDEWEB)

Gaussens, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-03-15

The first part of this work concerns the radiolysis of pure liquid ammonia. The fundamental importance of the dose rate and of the dose on the yield of radiolytic products has been demonstrated. By using a capture solute at concentrations of between 10{sup -3} and 1.2 mole s/litre, it has been possible to determine the yields of radicals and of molecules in the irradiated pure ammonia. During later work, it was possible to determine, by systematically varying the physico-chemical parameters, the most favorable conditions for carrying out the radiosynthesis; the maximum radiochemical yield of the hydrazine obtained has a value: G (N{sub 2}H{sub 4}) = 2.2/100 eV. An analysis of the molecular yields in the presence of deuterated solutes makes it possible to explain partially the role of the capture species. A project is also described for an installation producing hydrazine continuously; it is followed by an economic study of the process. From this work it appears that the yields of hydrazine obtained justify an industrial application, especially if strong radiation sources are available, for example nuclear reactors. (author) [French] La premiere partie de l'etude a porte sur la radiolyse de l'ammoniac liquide pur. Le role fondamental du debit de dose et de la dose sur les rendements des produits de radiolyse a ete mise en evidence. L'emploi de solute capteur dont les concentrations sont comprises entre 10{sup -3} et 1,2 mole/litre, a permis de determiner la valeur des rendements radicalaires et moleculaires dans l'ammoniac pur irradie. Au cours d'une etape ulterieure, une variation systematique des parametres physico-chimiques a permis de determiner les conditions les plus favorables a la radiosynthese le rendement radiochimique maximum de l'hydrazine obtenu a pour valeur: G(N{sub 2}H{sub 4}) 2,2/100 eV. L'analyse des rendements moleculaires en presence de solutes deuteres nous permet de rendre compte partiellement du role des capteurs. Un projet d'une installation

Indirect Spectrophotometric Determination of Trace Quantities of Hydrazine

Energy Technology Data Exchange (ETDEWEB)

Shabani, A. M. Haji; Dadfarnia, S.; Dehghan, K. [Yazd University, Yazd (Iran, Islamic Republic of)

2004-02-15

An indirect, sensitive and accurate method for the determination of trace amounts of hydrazine is described. The method is based on the oxidation of hydrazine by a known excess of iodate in the presence of hydrochloric acid. The unreacted iodate is used in the oxidation of hydroxylamine to nitrite. Sulfanilic acid is diazotized by the nitrite formed. The resulting diazonium ion is coupled with N-(1-naphthyl)ethylenediamine to form a stable azo dye, which shows an absorption maximum at 540 nm. Hydrazine can be determined in the range of 20-400 ng mL{sup -1} with a detection limit of 3.1 ng mL{sup -1}. The relative standard deviation for 50, 200 and 400 ng mL{sup -1} of hydrazine is 2, 1.5 and 1.3%, respectively (n = 10). The method was applied to the determination of hydrazine in water samples

Preparation of fine Ni powders from nickel hydrazine complex

International Nuclear Information System (INIS)

Park, Jung Woo; Chae, Eun H.; Kim, Sang H.; Lee, Jong Ho; Kim, Jeong Wook; Yoon, Seon Mi; Choi, Jae-Young

2006-01-01

Fine nickel powders with narrow size distribution have been prepared from the reduction of nickel hydrazine complexes in aqueous solution. The pure nickel hydrazine complexes, [Ni(N 2 H 4 ) 3 ]Cl 2 were prepared with the molar ratio of N 2 H 4 /Ni 2+ = 4.5, while a mixture of complexes, such as Ni(N 2 H 4 ) 2 Cl 2 , [Ni(N 2 H 4 ) 3 ]Cl 2 , and [Ni(NH 3 ) 6 ]Cl 2 were formed with N 2 H 4 /Ni 2+ 2+ to metallic Ni powder proceeded via the formation of nickel hydroxide which was reduced by hydrazine liberated from the ligand exchange reaction between the nickel hydrazine complex and NaOH. The standard deviation of the particle size decreased with the decreasing molar concentration of nickel hydrazine complex while the mean particle size increased. As the amount of hydrazine increased, the surface roughness of the particles was improved significantly due to the catalytic decomposition of the excess hydrazine at the surface of the nickel particle. It was found that average particle size could be controlled from 150 to 380 nm by adjusting the reaction molar ratio and temperature

Research on anhydrous hydrazine synthesis; Recherche sur la synthese de l'hydrazine anhydre

Energy Technology Data Exchange (ETDEWEB)

Gaussens, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-03-15

The first part of this work concerns the radiolysis of pure liquid ammonia. The fundamental importance of the dose rate and of the dose on the yield of radiolytic products has been demonstrated. By using a capture solute at concentrations of between 10{sup -3} and 1.2 mole s/litre, it has been possible to determine the yields of radicals and of molecules in the irradiated pure ammonia. During later work, it was possible to determine, by systematically varying the physico-chemical parameters, the most favorable conditions for carrying out the radiosynthesis; the maximum radiochemical yield of the hydrazine obtained has a value: G (N{sub 2}H{sub 4}) = 2.2/100 eV. An analysis of the molecular yields in the presence of deuterated solutes makes it possible to explain partially the role of the capture species. A project is also described for an installation producing hydrazine continuously; it is followed by an economic study of the process. From this work it appears that the yields of hydrazine obtained justify an industrial application, especially if strong radiation sources are available, for example nuclear reactors. (author) [French] La premiere partie de l'etude a porte sur la radiolyse de l'ammoniac liquide pur. Le role fondamental du debit de dose et de la dose sur les rendements des produits de radiolyse a ete mise en evidence. L'emploi de solute capteur dont les concentrations sont comprises entre 10{sup -3} et 1,2 mole/litre, a permis de determiner la valeur des rendements radicalaires et moleculaires dans l'ammoniac pur irradie. Au cours d'une etape ulterieure, une variation systematique des parametres physico-chimiques a permis de determiner les conditions les plus favorables a la radiosynthese le rendement radiochimique maximum de l'hydrazine obtenu a pour valeur: G(N{sub 2}H{sub 4}) 2,2/100 eV. L'analyse des rendements moleculaires en presence de solutes deuteres nous permet de rendre compte partiellement du role des

Analysis on Sealing Reliability of Bolted Joint Ball Head Component of Satellite Propulsion System

Science.gov (United States)

Guo, Tao; Fan, Yougao; Gao, Feng; Gu, Shixin; Wang, Wei

2018-01-01

Propulsion system is one of the important subsystems of satellite, and its performance directly affects the service life, attitude control and reliability of the satellite. The Paper analyzes the sealing principle of bolted joint ball head component of satellite propulsion system and discuss from the compatibility of hydrazine anhydrous and bolted joint ball head component, influence of ground environment on the sealing performance of bolted joint ball heads, and material failure caused by environment, showing that the sealing reliability of bolted joint ball head component is good and the influence of above three aspects on sealing of bolted joint ball head component can be ignored.

Epoxide reduction with hydrazine on graphene: a first principles study.

Science.gov (United States)

Kim, Min Chan; Hwang, Gyeong S; Ruoff, Rodney S

2009-08-14

Mechanisms for epoxide reduction with hydrazine on a single-layer graphene sheet are examined using quantum mechanical calculations within the framework of gradient-corrected spin-polarized density-functional theory. We find that the reduction reaction is mainly governed by epoxide ring opening which is initiated by H transfer from hydrazine or its derivatives. In addition, our calculations suggest that the epoxide reduction by hydrazine may predominantly follow a direct Eley-Rideal mechanism rather than a Langmuir-Hinshelwood mechanism. We also discuss the generation of various hydrazine derivatives during the reduction of graphene oxide with hydrazine and their potential contribution to lowering the barrier height of epoxide ring opening.

Integrated propulsion for near-Earth space missions. Volume 2: Technical

Science.gov (United States)

Dailey, C. L.; Meissinger, H. F.; Lovberg, R. H.; Zafran, S.

1981-01-01

The calculation approach is described for parametric analysis of candidate electric propulsion systems employed in LEO to GEO missions. Occultation relations, atmospheric density effects, and natural radiation effects are presented. A solar cell cover glass tradeoff is performed to determine optimum glass thickness. Solar array and spacecraft pointing strategies are described for low altitude flight and for optimum array illumination during ascent. Mass ratio tradeoffs versus transfer time provide direction for thruster technology improvements. Integrated electric propulsion analysis is performed for orbit boosting, inclination change, attitude control, stationkeeping, repositioning, and disposal functions as well as power sharing with payload on orbit. Comparison with chemical auxiliary propulsion is made to quantify the advantages of integrated propulsion in terms of weight savings and concomittant launch cost savings.

Hydrazine Determination in Sludge Samples by High Performance Liquid Chromatography

Energy Technology Data Exchange (ETDEWEB)

G. Elias; G. A. Park

2006-02-01

A high-performance liquid chromatographic method using ultraviolet (UV) detection was developed to detect and quantify hydrazine in a variety of environmental matrices. The method was developed primarily for sludge samples, but it is also applicable to soil and water samples. The hydrazine in the matrices was derivatized to their hydrazones with benzaldehyde. The derivatized hydrazones were separated using high performance liquid chromatography (HPLC) with a reversed-phase C-18 column in an isocratic mode with methanol-water (95:5, v/v), and detected with UV detection at 313 nm. The detection limit (25 ml) for the new analytical method is 0.0067 mg ml-1of hydrazine. Hydrazine showed low recovery in soil samples because components in soil oxidized hydrazine. Sludge samples that contained relatively high soil content also showed lower recovery. The technique is relatively simple and cost-effective, and is applicable for hydrazine analysis in different environmental matrices.

Upgrading non-oxidized carbon nanotubes by thermally decomposed hydrazine

Energy Technology Data Exchange (ETDEWEB)

Wang, Pen-Cheng, E-mail: wangpc@ess.nthu.edu.tw [Department of Engineering and System Science, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Graduate Program for Science and Technology of Synchrotron Light Source, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Liao, Yu-Chun [Department of Engineering and System Science, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Graduate Program for Science and Technology of Synchrotron Light Source, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Liu, Li-Hung [Department of Engineering and System Science, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Lai, Yu-Ling; Lin, Ying-Chang [National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Hsu, Yao-Jane [Graduate Program for Science and Technology of Synchrotron Light Source, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan (China)

2014-06-01

We found that the electrical properties of conductive thin films based on non-oxidized carbon nanotubes (CNTs) could be further improved when the CNTs consecutively underwent a mild hydrazine adsorption treatment and then a sufficiently effective thermal desorption treatment. We also found that, after several rounds of vapor-phase hydrazine treatments and baking treatments were applied to an inferior single-CNT field-effect transistor device, the device showed improvement in I{sub on}/I{sub off} ratio and reduction in the extent of gate-sweeping hysteresis. Our experimental results indicate that, even though hydrazine is a well-known reducing agent, the characteristics of our hydrazine-exposed CNT samples subject to certain treatment conditions could become more graphenic than graphanic, suggesting that the improvement in the electrical and electronic properties of CNT samples could be related to the transient bonding and chemical scavenging of thermally decomposed hydrazine on the surface of CNTs.

Upgrading non-oxidized carbon nanotubes by thermally decomposed hydrazine

Science.gov (United States)

Wang, Pen-Cheng; Liao, Yu-Chun; Liu, Li-Hung; Lai, Yu-Ling; Lin, Ying-Chang; Hsu, Yao-Jane

2014-06-01

We found that the electrical properties of conductive thin films based on non-oxidized carbon nanotubes (CNTs) could be further improved when the CNTs consecutively underwent a mild hydrazine adsorption treatment and then a sufficiently effective thermal desorption treatment. We also found that, after several rounds of vapor-phase hydrazine treatments and baking treatments were applied to an inferior single-CNT field-effect transistor device, the device showed improvement in Ion/Ioff ratio and reduction in the extent of gate-sweeping hysteresis. Our experimental results indicate that, even though hydrazine is a well-known reducing agent, the characteristics of our hydrazine-exposed CNT samples subject to certain treatment conditions could become more graphenic than graphanic, suggesting that the improvement in the electrical and electronic properties of CNT samples could be related to the transient bonding and chemical scavenging of thermally decomposed hydrazine on the surface of CNTs.

The platinum catalysed decomposition of hydrazine in acidic media

International Nuclear Information System (INIS)

Ananiev, A.V.; Tananaev, I.G.; Brossard, Ph.; Broudic, J.C.

2000-01-01

Kinetic study of the hydrazine decomposition in the solutions of HClO 4 , H 2 SO 4 and HNO 3 in the presence of Pt/SiO 2 catalyst has been undertaken. It was shown that the kinetics of the hydrazine catalytic decomposition in HClO 4 and H 2 SO 4 are identical. The process is determined by the heterogeneous catalytic auto-decomposition of N 2 H 4 on the catalyst's surface. The platinum catalysed hydrazine decomposition in the nitric acid solutions is a complex process, including heterogeneous catalytic auto-decomposition of N 2 H 4 , reaction of hydrazine with catalytically generated nitrous acid and the catalytic oxidation of hydrazine by nitric acid. The kinetic parameters of these reactions have been determined. The contribution of each reaction in the total process is determined by the liquid phase composition and by the temperature. (authors)

Performance evaluation of a colorimetric hydrazine dosimeter

Science.gov (United States)

Brenner, Karen P.; Rose-Pehrsson, Susan L.

1994-06-01

A dosimeter for real-time, colorimetric detection of hydrazine in air has been developed. The passive badge consists of a dosimeter card containing a vanillin solution coated on a thin paper substrate. The active patch consists of a thick cellulose substrate coated with a vanillin solution. When placed in a plastic sample holder attached to a personnel pump, up to 5 L/min can be drawn through the active badge substrate. Through a condensation reaction, vanillin reacts with hydrazine to form a colored product that absorbs in the visible region. The hydrazone formed in the reaction is yellow; its intensity is proportional to the dose. When exposed passively to hydrazine, the experimental detection limit is less than 20 ppb-hrs. Extrapolated results indicate a detection limit of less than 5 ppb-hrs for long sampling periods. Actively sampling of hydrazine vapors gives an experimental detection limit of less than 100 ppb-L at a sample rate of 5 L/min. Relative humidity effects on badge response were minor. High humidity enhanced the color development on the vanillin badge; while low humidity had no effect on badge response. Interference testing of the dosimeters revealed a tobacco smoke interference. Preliminary shelf life tests indicated no decrease in sensitivity to hydrazine when stored at room temperature for 6 months.

Mobility Spectrometer Studies on Hydrazine and Ammonia Detection

Science.gov (United States)

Niu, William; Eiceman, Gary; Szumlas, Andrew; Lewis, John

2011-01-01

An airborne vapor analyzer for detecting sub- to low- parts-per-million (ppm) hydrazine in the presence of higher concentration levels of ammonia has been under development for the Orion program. The detector is based on ambient pressure ionization and ion mobility characterization. The detector encompasses: 1) a membrane inlet to exclude particulate and aerosols from the analyzer inlet; 2) a method to separate hydrazine from ammonia which would otherwise lead to loss of calibration and quantitative accuracy for the hydrazine determination; and 3) response and quantitative determinations for both hydrazine and ammonia. Laboratory studies were made to explore some of these features including mobility measurements mindful of power, size, and weight issues. The study recommended the use of a mobility spectrometer of traditional design with a reagent gas and equipped with an inlet transfer line of bonded phase fused silica tube. The inlet transfer line provided gas phase separation of neutrals of ammonia from hydrazine at 50 C simplifying significantly the ionization chemistry that underlies response in a mobility spectrometer. Performance of the analyzer was acceptable between ranges of 30 to 80 C for both the pre-fractionation column and the drift tube. An inlet comprised of a combined membrane with valve-less injector allowed high speed quantitative determination of ammonia and hydrazine without cross reactivity from common metabolites such as alcohols, esters, and aldehydes. Preliminary test results and some of the design features are discussed.

System of ytterbium nitrate-hydrazine(mono-)dinitrate-water

International Nuclear Information System (INIS)

Khisaeva, D.A.; Katamanov, V.L.

1986-01-01

Solubility in ternary systems ytterbium nitrate-hydrazine monohydrate-water and ytterbium nitrate-hydrazine dinitrate-water is studied at 25 and 50 deg C. Salt components of both systems do not form with each other double addition compounds in the chosen temperature range. Initial salts are equilibrium solid phases of saturated solutions. Correlation of the range of primary crystallization of nitrate acydocomplexes of lanthanides formed in similar systems with their atomic number is considered. It is shown that hydrazine dinitrate can be used for separation of rare earth elements of cerium group

Determination of U(IV) and hydrazine nitrate by volumetry

International Nuclear Information System (INIS)

Cao Xi; Wang Nanjie; Zhang Tao; Wang Lin; Guo Yuhua

2006-01-01

To be determined U(IV) and hydrazine nitrate in exist together, chromium (VI) and 1,10-phenanthroline is used individually as oxidation titrator and indicator for U(IV), and N-bromineimino and methyl red is used individually as oxidation titrator and indicator for hydrazine nitrate, U(IV) and hydrazine nitrate in the same sample is determined sequentially in the nitric acid by adjusting concentration of nitric acid. Results show that the precision is better than 2.0% when the mass concentration of U(IV) is ranged over 5.5-205 mg/mL; and the precision is better than 2.0% when the concentration of hydrazine nitrate is ranged over 0.05-1.0 mol/L. (authors)

The reaction of hydrazine nitrate with nitric acid

International Nuclear Information System (INIS)

Kida, Takashi; Sugikawa, Susumu

2004-03-01

It is known that hydrazine nitrate used in nuclear fuel reprocessing plants is an unstable substance thermochemically like hydroxylamine nitrate. In order to take the basic data regarding the reaction of hydrazine nitrate with nitric acid, initiation temperatures and heats of this reaction, effect of impurity on initiation temperature and self-accelerating reaction when it holds at constant temperature for a long time were measured by the pressure vessel type reaction calorimeter etc. In this paper, the experimental data and evaluation of the safe handling of hydrazine nitrate in nuclear fuel reprocessing plants are described. (author)

Research on anhydrous hydrazine synthesis

International Nuclear Information System (INIS)

Gaussens, G.

1967-03-01

The first part of this work concerns the radiolysis of pure liquid ammonia. The fundamental importance of the dose rate and of the dose on the yield of radiolytic products has been demonstrated. By using a capture solute at concentrations of between 10 -3 and 1.2 mole s/litre, it has been possible to determine the yields of radicals and of molecules in the irradiated pure ammonia. During later work, it was possible to determine, by systematically varying the physico-chemical parameters, the most favorable conditions for carrying out the radiosynthesis; the maximum radiochemical yield of the hydrazine obtained has a value: G (N 2 H 4 ) = 2.2/100 eV. An analysis of the molecular yields in the presence of deuterated solutes makes it possible to explain partially the role of the capture species. A project is also described for an installation producing hydrazine continuously; it is followed by an economic study of the process. From this work it appears that the yields of hydrazine obtained justify an industrial application, especially if strong radiation sources are available, for example nuclear reactors. (author) [fr

Hydrazine determination in presence of uranium by modified spectrophotometric method

International Nuclear Information System (INIS)

Velavendan, P.; Pandey, N.K.; Kamachi Mudali, U.; Natarajan, R.

2011-01-01

In the present work an indirect, sensitive and accurate method for the determination of hydrazine is described. The method is based on the formation of yellow coloured azine complex by post column derivatization of hydrazine with P-dimethylamino benzaldehyde. The formed yellow coloured complex is stable in acidic medium and has a maximum absorption at 460 nm. Interference due to uranium was studied and the method was applied for the determination of hydrazine in presence of uranium in aqueous stream of nuclear fuel reprocessing. A calibration graph was made for the concentration range of hydrazine from 0.05 ppm to 10 ppm with RSD 0.807% and correlation coefficient of 0.99996. (author)

Hydrazine - hydrate water regime and operation of fuel elements

International Nuclear Information System (INIS)

Pashevitch, V.I.; Pashevitch, D.V.; Bogancs, J.; Tilky, P.

1997-01-01

Water chemistries currently used in WWER reactors are potassium based water chemistry (KOH) to adjust the pH with ammonia or hydrazine as oxygen scavenger. Based on the measurements of Zr 95 which is a corrosion product of the zirconium cladding, it is shown in this paper that the amount of corrosion products accompanying the reactor shutdown is smaller when hydrazine is used. This is particularly obvious on PAKS 1 and 2 when Zr 95 measurements are performed before and after switching the water chemistry from ammonia to hydrazine. It is concluded that the main advantage of using the hydrazine water chemistry is to decrease the thickness of the corrosion product layer formed on the fuel cladding, therefore the fuel temperature can be kept low. It is estimated that the fuel temperature increase due to the layer of corrosion products is 120 deg. C for KOLA 3 which is operated with ammonia water chemistry. (author). 5 figs

Hydrazine - hydrate water regime and operation of fuel elements

Energy Technology Data Exchange (ETDEWEB)

Pashevitch, V I; Pashevitch, D V [Pand Co. (Russian Federation); Bogancs, J; Tilky, P [Paks NPP (Hungary)

1997-02-01

Water chemistries currently used in WWER reactors are potassium based water chemistry (KOH) to adjust the pH with ammonia or hydrazine as oxygen scavenger. Based on the measurements of Zr 95 which is a corrosion product of the zirconium cladding, it is shown in this paper that the amount of corrosion products accompanying the reactor shutdown is smaller when hydrazine is used. This is particularly obvious on PAKS 1 and 2 when Zr 95 measurements are performed before and after switching the water chemistry from ammonia to hydrazine. It is concluded that the main advantage of using the hydrazine water chemistry is to decrease the thickness of the corrosion product layer formed on the fuel cladding, therefore the fuel temperature can be kept low. It is estimated that the fuel temperature increase due to the layer of corrosion products is 120 deg. C for KOLA 3 which is operated with ammonia water chemistry. (author). 5 figs.

Oxygen consumption by hydrazine in long sample lines

International Nuclear Information System (INIS)

Chi, Lisheng; Turner, Carl-W.

2012-09-01

In nuclear power plants secondary side system dissolved oxygen concentration is a strictly controlled chemistry parameter intended to minimize corrosion and fouling of steam cycle components. Low dissolved oxygen concentration is maintained by a combination of mechanical de-aeration and chemical reaction. The dissolved oxygen concentration in feedwater is monitored by sampling systems to ensure it remains within station specification during operation. The sample lines in a nuclear power plant's sampling system can be from 5 to nearly 200 meters in length, resulting in sample residence times between the take-off point to the analyzer from a few seconds to several minutes, depending on the flow rate and the length of the sample line. For many chemical parameters the residence time is of no concern. For measurements of dissolved oxygen and hydrazine in the secondary coolant, however, for residence times longer than one minute, it is uncertain whether the sample is representative of conditions in the secondary coolant, especially for samples taken from locations where the temperature is well over 100 deg. C. To address this concern, a series of tests were conducted under both warm-up and power operation conditions, respectively, to investigate the effect of temperature, residence time, sample line length, surface area, hydrazine-to-oxygen ratio, and the concentrations of dissolved oxygen and hydrazine on the consumption of oxygen by hydrazine. The test results revealed that dissolved oxygen measurements in CANDU plants are underestimated to various degrees, depending on the sampling system operating conditions. Two distinct types of behaviours are observed for the oxygen removal rate: 1) the percentage removal of dissolved oxygen is invariant with time during the tests, and increases with increasing residence time in the test section, when the reaction between hydrazine and oxygen is better described by a homogenous reaction mechanism, and 2) the percentage oxygen

Clustering of amines and hydrazines in atmospheric nucleation

Science.gov (United States)

Li, Siyang; Qu, Kun; Zhao, Hailiang; Ding, Lei; Du, Lin

2016-06-01

It has been proved that the presence of amines in the atmosphere can enhance aerosol formation. Hydrazine (HD) and its substituted derivatives, monomethylhydrazine (MMH) and unsymmetrical dimethylhydrazine (UDMH), which are organic derivatives of amine and ammonia, are common trace atmospheric species that may contribute to the growth of nucleation clusters. The structures of the hydrazine and amine clusters containing one or two common nucleation molecules (ammonia, water, methanol and sulfuric acid) have been optimized using density functional theory (DFT) methods. The clusters growth mechanism has been explored from the thermochemistry by calculating the Gibbs free energies of adding an ammonia, water, methanol or sulfuric acid molecule step by step at room temperature, respectively. The results show that hydrazine and its derivatives could enhance heteromolecular homogeneous nucleation in the earth's atmosphere.

Assessment of Cost Impacts of Using Non-Toxic Propulsion in Satellites

Science.gov (United States)

Schiebener, P. J.; Gies, O.; Stuhlberger, J.; Schmitz, H.-D.

2002-01-01

The growing costs of space missions, the need for increased mission performance, and concerns associated with environmental issues deeply influence propulsion system design and propellant selection criteria. A propellant's performance was defined in the past exclusively in terms of specific impulse and density, but now high-performance, non-toxic, non-sophisticated mono- propellant systems are key drivers, and are considered for development to replace the traditional hydrazine (N2H4) mono-propellant thrusters. The mono-propellants under consideration are propellant formulations, which should be environmentally friendly, should have a high density, equal or better performance and better thermal characteristics than hydrazine. These considerations raised interest specially in the candidates of Hydroxylammonium Nitrate (HAN)-based propellants, Ammoniumdinitramide (ADN)-based propellants, Tri-ethanol (TEAN)-based propellants, Hydrazinium Nitroformate (HNF)-based propellants, Hydrogen Peroxide (H2O2)-based propellants. A near-term objective in consideration of satellite related process optimisation is to significantly reduce on-ground operations costs and at the same time improve mission performance. A far-term objective is to obtain a system presenting a very high performance, illustrated by a high specific impulse. Moving to a "non-toxic" propulsion system seems to be a solution to these two goals. The sought after benefits for non-toxic spacecraft mono-propellant propulsion are under investigation taking into account the four main parameters which are mandatory for customer satisfaction while meeting the price constraints: - Reliability, availability, maintainability and safety, - Manufacturing, assembly, integration and test, - Launch preparation and support, - Ground support equipment. These benefits of non-toxic mono-propellants can be proven by various examples, like an expected reduction of development costs due the non-toxicity of propellants which might allow

Hydrazine reagents as derivatizing agents in environmental analysis--a critical review.

Science.gov (United States)

Vogel, M; Büldt, A; Karst, U

2000-04-01

Hydrazine reagents are a well-known group of derivatizing agents for the determination of aldehydes and ketones in liquid and gaseous samples. Within this article, the most important hydrazine reagents are critically summarized, and their major applications in different fields, including environmental analysis, food chemistry and industrial analysis are introduced. As 2,4-dinitrophenylhydrazine (DNPH) is the basic reagent for several international standard procedures, its properties are discussed in detail. Particular focus is directed on the chemistry of the hydrazine reagents, and chemical interferences are considered. Recent methods for the determination of various oxidants using hydrazine reagents are presented as well. Due to limited space, this review does not cover the related field of carbohydrate analysis, although many chemical aspects are similar.

Enthalpy of Formation of N2H4 (Hydrazine) Revisited.

Science.gov (United States)

Feller, David; Bross, David H; Ruscic, Branko

2017-08-17

In order to address the accuracy of the long-standing experimental enthalpy of formation of gas-phase hydrazine, fully confirmed in earlier versions of Active Thermochemical Tables (ATcT), the provenance of that value is re-examined in light of new high-end calculations of the Feller-Peterson-Dixon (FPD) variety. An overly optimistic determination of the vaporization enthalpy of hydrazine, which created an unrealistically strong connection between the gas phase thermochemistry and the calorimetric results defining the thermochemistry of liquid hydrazine, was identified as the probable culprit. The new enthalpy of formation of gas-phase hydrazine, based on balancing all available knowledge, was determined to be 111.57 ± 0.47 kJ/mol at 0 K (97.42 ± 0.47 kJ/mol at 298.15 K). Close agreement was found between the ATcT (even excluding the latest theoretical result) and the FPD enthalpy.

Some observations on hydrazine and ammonia based chemistries in PWRs

International Nuclear Information System (INIS)

Brunning, J.; Cake, P.; Harper, A.; Sims, H.E.

1997-01-01

This paper presents a comparison of factors related to activated corrosion product transport in pressurized water reactors (PWRs) operating hydrazine and ammonia-based chemistries. Measurements of the concentrations of corrosion products in the coolant of reactors operating both chemistry regimes are compared under steady operation and during shutdown. These data allow some comparisons to be drawn of corrosion product transport under ammonia and hydrazine based chemistries. Experimental measurements of electrochemical potential under PWR conditions in the presence and absence of radiation fields and under hydrazine and ammonia chemistries are also presented. (author). 4 refs, 5 figs, 2 tabs

Some observations on hydrazine and ammonia based chemistries in PWRs

Energy Technology Data Exchange (ETDEWEB)

Brunning, J; Cake, P; Harper, A; Sims, H E [AEA Technology, Oxon (United Kingdom)

1997-02-01

This paper presents a comparison of factors related to activated corrosion product transport in pressurized water reactors (PWRs) operating hydrazine and ammonia-based chemistries. Measurements of the concentrations of corrosion products in the coolant of reactors operating both chemistry regimes are compared under steady operation and during shutdown. These data allow some comparisons to be drawn of corrosion product transport under ammonia and hydrazine based chemistries. Experimental measurements of electrochemical potential under PWR conditions in the presence and absence of radiation fields and under hydrazine and ammonia chemistries are also presented. (author). 4 refs, 5 figs, 2 tabs.

Advanced Chemical Propulsion System Study

Science.gov (United States)

Portz, Ron; Alexander, Leslie; Chapman, Jack; England, Chris; Henderson, Scott; Krismer, David; Lu, Frank; Wilson, Kim; Miller, Scott

2007-01-01

A detailed; mission-level systems study has been performed to show the benefit resulting from engine performance gains that will result from NASA's In-Space Propulsion ROSS Cycle 3A NRA, Advanced Chemical Technology sub-topic. The technology development roadmap to accomplish the NRA goals are also detailed in this paper. NASA-Marshall and NASA-JPL have conducted mission-level studies to define engine requirements, operating conditions, and interfaces. Five reference missions have been chosen for this analysis based on scientific interest, current launch vehicle capability and trends in space craft size: a) GTO to GEO, 4800 kg, delta-V for GEO insertion only approx.1830 m/s; b) Titan Orbiter with aerocapture, 6620 kg, total delta V approx.210 m/s, mostly for periapsis raise after aerocapture; c) Enceladus Orbiter (Titan aerocapture) 6620 kg, delta V approx.2400 m/s; d) Europa Orbiter, 2170 kg, total delta V approx.2600 m/s; and e) Mars Orbiter, 2250 kg, total delta V approx.1860 m/s. The figures of merit used to define the benefit of increased propulsion efficiency at the spacecraft level include propulsion subsystem wet mass, volume and overall cost. The objective of the NRA is to increase the specific impulse of pressure-fed earth storable bipropellant rocket engines to greater than 330 seconds with nitrogen tetroxide and monomothylhydrazine propellants and greater than 335 , seconds with nitrogen tetroxide and hydrazine. Achievement of the NRA goals will significantly benefit NASA interplanetary missions and other government and commercial opportunities by enabling reduced launch weight and/or increased payload. The study also constitutes a crucial stepping stone to future development, such as pump-fed storable engines.

Ag supported on carbon fiber cloth as the catalyst for hydrazine oxidation in alkaline medium

International Nuclear Information System (INIS)

Liu, Ran; Ye, Ke; Gao, Yinyi; Zhang, Wenping; Wang, Guiling; Cao, Dianxue

2015-01-01

Highlights: • CFC supported microspherical Ag is obtained by square-wave potential method. • Ag/CFC electrode has high catalytic activity toward hydrazine oxidation. • Hydrazine oxidation on the electrode proceeds by a near 4-electron pathway. - Abstract: Silver particles with microspheric structure are directly electrodeposited on carbon fiber cloth (CFC) substrate by square-wave potential electrodeposition method. The electrocatalytic behaviors of the Ag/CFC electrode toward hydrazine oxidation in alkaline solution are examined by cyclic voltammetry and chronoamperometry. An onset oxidation potential of -0.5 V and a peak current density of 30 mA cm −2 are achieved in the solution containing 1.0 mol L −1 KOH and 20.0 mmol L −1 hydrazine. The microspheric structure of the Ag/CFC electrode provides large electroactive surface area, hence, abundant active sites are vacant for hydrazine oxidation. The calculated apparent activation energies at different potentials show that hydrazine electro-oxidation at higher potential has faster kinetics than that at lower potential. In addition, the transfer electron number of hydrazine oxidation reaction on the Ag/CFC electrode is close to four, suggesting hydrazine is almost completely electrooxidized on the electrode and the full use of hydrazine fuel is basically achieved.

Catalog of components for electric and hybrid vehicle propulsion systems

Science.gov (United States)

Eissler, H. C.

1981-01-01

This catalog of commercially available electric and hybrid vehicle propulsion system components is intended for designers and builders of these vehicles and contains 50 categories of components. These categories include those components used between the battery terminals and the output axle hub, as well as some auxiliary equipment. An index of the components and a listing of the suppliers and their addresses and phone numbers are included.

Hematoxylin multi-wall carbon nanotubes modified glassy carbon electrode for electrocatalytic oxidation of hydrazine

International Nuclear Information System (INIS)

Zare, Hamid R.; Nasirizadeh, Navid

2007-01-01

A new hydrazine sensor has been fabricated by immobilizing hematoxylin at the surface of a glassy carbon electrode (GCE) modified with multi-wall carbon nanotube (MWCNT). The adsorbed thin films of hematoxylin on the MWCNT modified GCE show one pair of peaks with surface confined characteristics. The hematoxylin MWCNT (HMWCNT) modified GCE shows highly catalytic activity toward hydrazine electro-oxidation. The results show that the peak potential of hydrazine at HMWCNT modified GCE surface shifted by about 167 and 255 mV toward negative values compared with that at an MWCNT and activated modified GCE surface, respectively. In addition, at HMWCNT modified electrode surface remarkably improvement the sensitivity of determination of hydrazine. The kinetic parameters, such as the electron transfer coefficient, α, and the standard heterogeneous rate constant, k 0 , for oxidation of hydrazine at the HMWCNT modified GCE were determined and also is shown that the heterogeneous rate constant, k', is strongly potential dependent. The overall number of electron involved in the catalytic oxidation of hydrazine and the number of electrons involved in the rate-determining steps are 2 and 1, respectively. The amperometric detection of hydrazine is carried out at 220 mV in 0.1 M phosphate buffer solution (pH 7) with linear response range 2.0-122.8 μM hydrazine, detection limit of 0.68 μM and sensitivity of 0.0208 μA μM -1 . Finally the amperometric response for hydrazine determination is reproducible, fast and extremely stable, with no loss in sensitivity over a continual 400 s operation

A rhodol-based fluorescent chemosensor for hydrazine and its application in live cell bioimaging

Science.gov (United States)

Tiensomjitr, Khomsan; Noorat, Rattha; Wechakorn, Kanokorn; Prabpai, Samran; Suksen, Kanoknetr; Kanjanasirirat, Phongthon; Pewkliang, Yongyut; Borwornpinyo, Suparerk; Kongsaeree, Palangpon

2017-10-01

A rhodol cinnamate fluorescent chemosensor (RC) has been developed for selective detection of hydrazine (N2H4). In aqueous medium, the rhodol-based probe exhibited high selectivity for hydrazine among other molecules. The addition of hydrazine triggered a fluorescence emission with 48-fold enhancement based on hydrazinolysis and a subsequent ring-opening process. The chemical probe also displayed a selective colorimetric response toward N2H4 from colorless solution to pink, readily observed by the naked eye. The detection limit of RC for hydrazine was calculated to be 300 nM (9.6 ppb). RC is membrane permeable and was successfully demonstrated to detect hydrazine in live HepG2 cells by confocal fluorescence microscopy.

Antisymmetric Amino-Wagging Band of Hydrazine up toK‧ = 13 Levels

Science.gov (United States)

Gulaczyk, Iwona; Kre, Marek; Valentin, Alain

1997-12-01

A newly recorded high-resolution infrared spectrum of hydrazine has been studied in the 729-1198 cm-1region (the ν12antisymmetric wagging band) with a resolution of 0.002 cm-1. About 1350 transitions withK‧ from 7 to 13 have been newly assigned and about 2350 transitions with lower values ofK‧ reanalyzed with the improved precision. The effective parameters have been calculated separately for each value ofK‧ using the Hougen-Ohashi hamiltonian for hydrazine. The extended assignment completes the analysis of the ν12band of hydrazine.

Effect of Water Chemistry Factors on Flow Accelerated Corrosion : pH, DO, Hydrazine

International Nuclear Information System (INIS)

Lee, Eun Hee; Kim, Kyung Mo; Kim, Hong Pyo

2013-01-01

Flow accelerated corrosion(FAC) of the carbon steel piping in pressurized water reactors(PWRs) has been major issue in nuclear industry. Severe accident at Surry Unit 2 in 1986 initiated the worldwide interest in this area. Major parameters influencing FAC are material composition, microstructure, water chemistry, and hydrodynamics. Qualitative behaviors of FAC have been well understood but quantitative data about FAC have not been published for proprietary reason. In order to minimize the FAC in PWRs, the optimal method is to control water chemistry factors. Chemistry factors influencing FAC such as pH, corrosion potential, and hydrazine contents were reviewed in this paper. FAC rate decreased with pH up to 10 because magnetite solubility decreased with pH. Corrosion potential is generally controlled dissolved oxygen (DO) and hydrazine in secondary water. DO increased corrosion potential. FAC rate decreased with DO by stabilizing magnetite at low DO concentration or by formation of hematite at high DO concentration. Even though hydrazine is generally used to remove DO, hydrazine itself thermally decomposed to ammonia, nitrogen, and hydrogen raising pH. Hydrazine could react with iron and increased FAC rate. Effect of hydrazine on FAC is rather complex and should be careful in FAC analysis. FAC could be managed by adequate combination of pH, corrosion potential, and hydrazine

Research about the hydrazine-ammonia system. Untersuchungen am system hydrazin-ammoniak

Energy Technology Data Exchange (ETDEWEB)

None

1967-03-15

Some qualities of hydrazine-ammonia mixtures are investigated with regard to their use as rocket fuels by means of conventional measuring methods being adapted to the problems of these systems vapor pressures, densities and viscosities of such mixtures are determined as functions of compositions. The findings of these studies show in view to vapor pressure and densities deviations from ideal behavior, which are however, of disadvantage when using this system as fuel for rocket engines.

INSPACE CHEMICAL PROPULSION SYSTEMS AT NASA's MARSHALL SPACE FLIGHT CENTER: HERITAGE AND CAPABILITIES

Science.gov (United States)

McRight, P. S.; Sheehy, J. A.; Blevins, J. A.

2005-01-01

NASA s Marshall Space Flight Center (MSFC) is well known for its contributions to large ascent propulsion systems such as the Saturn V rocket and the Space Shuttle external tank, solid rocket boosters, and main engines. This paper highlights a lesser known but very rich side of MSFC-its heritage in the development of in-space chemical propulsion systems and its current capabilities for spacecraft propulsion system development and chemical propulsion research. The historical narrative describes the flight development activities associated with upper stage main propulsion systems such as the Saturn S-IVB as well as orbital maneuvering and reaction control systems such as the S-IVB auxiliary propulsion system, the Skylab thruster attitude control system, and many more recent activities such as Chandra, the Demonstration of Automated Rendezvous Technology (DART), X-37, the X-38 de-orbit propulsion system, the Interim Control Module, the US Propulsion Module, and multiple technology development activities. This paper also highlights MSFC s advanced chemical propulsion research capabilities, including an overview of the center s Propulsion Systems Department and ongoing activities. The authors highlight near-term and long-term technology challenges to which MSFC research and system development competencies are relevant. This paper concludes by assessing the value of the full range of aforementioned activities, strengths, and capabilities in light of NASA s exploration missions.

Optimization of wet lay-up conditions for steam generators hydrazine chemical treatment

International Nuclear Information System (INIS)

Long, A.; Organista, M.; Brun, C.; Combrade, P.

2002-01-01

Since a long time, hydrazine is used as a chemical agent to prevent corrosion of unalloyed steels. This is a conventional treatment widely used by nuclear power plant operators. But its application in SG lay-up at French nuclear power plants has, however, lead to some drawbacks. Effluent releases: Due to regulation relative to release of hydrazine and alkaline chemical compounds, some plant operators limit the concentrations of reagents to levels that could lead to insufficient protection of materials. Safety hazards associated with SG nitrogen blanketing: Prohibiting use of nitrogen blankets for SG wet lay-up due to associated safety hazards could likewise jeopardize corrosion protection at normally specified hydrazine levels. As the exact limits of hydrazine action against corrosion during SG lay-up are not well known, it is sometimes difficult to evaluate the risk associated to low dosage of N 2 H 4 . In order to answer to these problems, Framatome ANP (France) decided to carry out a test program aimed to determine the limit conditions for use of hydrazine in a wet lay-up environment. (authors)

Concentric-Electrode Organic Electrochemical Transistors: Case Study for Selective Hydrazine Sensing

Directory of Open Access Journals (Sweden)

Sébastien Pecqueur

2017-03-01

Full Text Available We report on hydrazine-sensing organic electrochemical transistors (OECTs with a design consisting of concentric annular electrodes. The design engineering of these OECTs was motivated by the great potential of using OECT sensing arrays in fields such as bioelectronics. In this work, poly(3,4-ethylenedioxythiophene:poly(styrenesulfonate (PEDOT:PSS-based OECTs have been studied as aqueous sensors that are specifically sensitive to the lethal hydrazine molecule. These amperometric sensors have many relevant features for the development of hydrazine sensors, such as a sensitivity down to 10−5 M of hydrazine in water, an order of magnitude higher selectivity for hydrazine than for nine other water-soluble common analytes, the capability to entirely recover its base signal after water flushing, and a very low operation voltage. The specificity for hydrazine to be sensed by our OECTs is caused by its catalytic oxidation at the gate electrode, and enables an increase in the output current modulation of the devices. This has permitted the device-geometry study of the whole series of 80 micrometric OECT devices with sub-20-nm PEDOT:PSS layers, channel lengths down to 1 µm, and a specific device geometry of coplanar and concentric electrodes. The numerous geometries unravel new aspects of the OECT mechanisms governing the electrochemical sensing behaviours of the device—more particularly the effect of the contacts which are inherent at the micro-scale. By lowering the device cross-talk, micrometric gate-integrated radial OECTs shall contribute to the diminishing of the readout invasiveness and therefore further promote the development of OECT biosensors.

Reaction kinetics of hydrazine neutralization in steam generator wet lay-up solution: Identifying optimal degradation conditions

International Nuclear Information System (INIS)

Schildermans, Kim; Lecocq, Raphael; Girasa, Emmanuel

2012-09-01

During a nuclear power plant outage, hydrazine is used as an oxygen scavenger in the steam generator lay-up solution. However, due to the carcinogenic effects of hydrazine, more stringent discharge limits are or will be imposed in the environmental permits. Hydrazine discharge could even be prohibited. Consequently, hydrazine alternatives or hydrazine degradation before discharge is needed. This paper presents the laboratory tests performed to characterize the reaction kinetics of hydrazine neutralization using bleach or hydrogen peroxide, catalyzed with either copper sulfate (CuSO 4 ) or potassium permanganate (KMnO 4 ). The tests are performed on two standard steam generator lay-up solutions based on different pH control agents: ammonia or ethanolamine. Different neutralization conditions are tested by varying temperature, oxidant addition, and catalyst concentration, among others, in order to identify the optimal parameters for hydrazine neutralization in a steam generator wet lay-up solution. (authors)

Evaluation of consequence due to higher hydrazine content in partitioning stream of PUREX process

Energy Technology Data Exchange (ETDEWEB)

Kumar, K. Suresh [Bhabha Atomic Research Centre, Mumbai (India). Special Nuclear Recycle Facility

2016-07-01

Hydrazine nitrate is being used as a stabilizer for U(IV) as well as Pu(III) during partitioning of Pu in PUREX process by scavenging the nitrous acid present along with nitric acid. As hydrazine hydrate as well as its salts have been successfully used for scrubbing of degradation products of TBP to aqueous phase, experiments were conducted to evaluate the consequence of hydrazine content during Pu partitioning. It was observed that higher amount of hydrazine nitrate along with uranous nitrate in the partitioning stream of PUREX process leads to build up of DBP in aqueous phase and resulted in precipitation of Pu.

Hydrazine selective dual signaling chemodosimetric probe in physiological conditions and its application in live cells

Energy Technology Data Exchange (ETDEWEB)

Nandi, Sandip; Sahana, Animesh; Mandal, Sandip [Department of Chemistry, The University of Burdwan, Burdwan, 713104 West Bengal (India); Sengupta, Archya; Chatterjee, Ansuman [Department of Zoology, Visva Bharati University, Santiniketan, West Bengal (India); Safin, Damir A., E-mail: damir.a.safin@gmail.com [Institute of Condensed Matter and Nanosciences, Molecules, Solids and Reactivity (IMCN/MOST), Université catholique de Louvain, Place L. Pasteur 1, 1348 Louvain-la-Neuve (Belgium); Babashkina, Maria G.; Tumanov, Nikolay A.; Filinchuk, Yaroslav [Institute of Condensed Matter and Nanosciences, Molecules, Solids and Reactivity (IMCN/MOST), Université catholique de Louvain, Place L. Pasteur 1, 1348 Louvain-la-Neuve (Belgium); Das, Debasis, E-mail: ddas100in@yahoo.com [Department of Chemistry, The University of Burdwan, Burdwan, 713104 West Bengal (India)

2015-09-17

A rhodamine–cyanobenzene conjugate, (E)-4-((2-(3′,6′-bis(diethylamino)-3-oxospiro[isoindoline-1,9′-xanthene] -2-yl)ethylimino)methyl)benzonitrile (1), which structure has been elucidated by single crystal X-ray diffraction, was synthesized for selective fluorescent “turn-on” and colorimetric recognition of hydrazine at physiological pH 7.4. It was established that 1 detects hydrazine up to 58 nM. The probe is useful for the detection of intracellular hydrazine in the human breast cancer cells MCF-7 using a fluorescence microscope. Spirolactam ring opening of 1, followed by its hydrolysis, was established as a probable mechanism for the selective sensing of hydrazine. - Highlights: • A selective rhodamine–cyanobenzene conjugate is synthesized. • The conjugate is a selective dual signaling chemodosimetric probe towards hydrazine. • Spirolactam ring opening of the probe, followed by its hydrolysis, is the sensing mechanism. • The probe detects hydrazine in the human breast cancer cells MCF-7 imaging.

A new potentiometric determination of hydrazine in the presence of uranium(IV)

International Nuclear Information System (INIS)

Singh, N.S.; Mohan, S.V.

1996-01-01

The present method describes the determination of hydrazine by making use of potentiometric titration technique. The underlying principle is back titration of unreacted excess cerium remaining after the complete oxidation of hydrazine. Standardized ferrous ammonium sulfate was used for titration. This method was applied to 'real samples' generated from a nuclear reprocessing plant wherein control of hydrazine is of paramount importance. The interference of U(IV), Cr(III), U(VI), nitrite, and chloride was studied and of all these ions the way to eliminate the interference of U(IV) was only attempted. The relative standard deviations (RSD) for synthetic as well as 'real samples' were determined. The method gives RSD of less than 1% in the range of 1 mg to 20 mg of hydrazine. The error in the range 3 mg to 17 mg was found to be less than 1%. (author). 5 refs., 3 tabs

Hydrazine blending and storage facility, interim response action, draft implementation document for rinsewater transfer, phase 2

Energy Technology Data Exchange (ETDEWEB)

1991-08-09

This Draft Implementation Document (ID) for Rinsewater Transfer has been prepared as a requirement for conducting and completing the Interim Response Action (IRA) at the Hydrazine Blending and Storage Facility (HBSF) located at Rocky Mountain Arsenal (RMA) in Commerce City, Colorado. This document has been prepared in accordance with requirements set forth in the October 1988 Final Decision Document for the HBSF IRA (Peer, 1988) and the Amendment to the Final Decision Document (HLA, 1991). The HBSF IRA task was separated into two phases that comprise complete decommissioning of the HBSF as cited in the Federal Facility Agreement. The design portion of Phase I of the HBSF IRA included analytical methods development and laboratory certification for analysis of hydrazine fuel compounds (hydrazine, monomethyl hydrazine) (MMH), and unsymmetrical dimethyl hydrazine (UDMH) and n-nitrosodimethylamine (NDMA) in HBSF rinsewater, chemical characterization of hydrazine rinsewater, bench- and pilot-scale testing of ultraviolet (UV) light/chemical oxidation treatment systems for treatment of hydrazine rinsewater, full-scale startup testing of a UV light/chemical oxidation treatment system, and air monitoring during startup testing as described in the Draft Final Treatment Report (HLA, 1991).

Electric propulsion options for 10 kW class earth space missions

Science.gov (United States)

Patterson, M. J.; Curran, Francis M.

1989-01-01

Five and 10 kW ion and arcjet propulsion system options for a near-term space demonstration experiment have been evaluated. Analyses were conducted to determine first-order propulsion system performance and system component mass estimates. Overall mission performance of the electric propulsion systems was quantified in terms of the maximum thrusting time, total impulse, and velocity increment capability available when integrated onto a generic spacecraft under fixed mission model assumptions. Maximum available thrusting times for the ion-propelled spacecraft options, launched on a DELTA II 6920 vehicle, range from approximately 8,600 hours for a 4-engine 10 kW system to more than 29,600 hours for a single-engine 5 kW system. Maximum total impulse values and maximum delta-v's range from 1.2x10(7) to 2.1x10(7) N-s, and 3550 to 6200 m/s, respectively. Maximum available thrusting times for the arcjet propelled spacecraft launched on the DELTA II 6920 vehicle range from approximately 528 hours for the 6-engine 10 kW hydrazine system to 2328 hours for the single-engine 5 kW system. Maximum total impulse values and maximum delta-v's range from 2.2x10(6) to 3.6x10(6) N-s, and approximately 662 to 1072 m/s, respectively.

Electric Propulsion Options for 10 kW Class Earth-Space Missions

Science.gov (United States)

Patterson, M. J.; Curran, Francis M.

1989-01-01

Five and 10 kW ion and arcjet propulsion system options for a near-term space demonstration experiment were evaluated. Analyses were conducted to determine first-order propulsion system performance and system component mass estimates. Overall mission performance of the electric propulsion systems was quantified in terms of the maximum thrusting time, total impulse, and velocity increment capability available when integrated onto a generic spacecraft under fixed mission model assumptions. Maximum available thrusting times for the ion-propelled spacecraft options, launched on a DELTA 2 6920 vehicle, range from approximately 8,600 hours for a 4-engine 10 kW system to more than 29,600 hours for a single-engine 5 kW system. Maximum total impulse values and maximum delta-v's range from 1.2x10 (exp 7) to 2.1x10 (exp 7) N-s, and 3550 to 6200 m/s, respectively. Maximum available thrusting times for the arcjet propelled spacecraft launched on the DELTA 2 6920 vehicle range from approximately 528 hours for the 6-engine 10 kW hydrazine system to 2328 hours for the single-engine 5 kW system. Maximum total impulse values and maximum delta-v's range from 2.2x10 (exp 6) to 3.6x10 (exp 6) N-s, and approximately 662 to 1072 m/s, respectively.

Radiation chemistry of aqueous solutions of hydrazine at elevated temperatures: Pt. 2. Solutions containing oxygen

International Nuclear Information System (INIS)

Buxton, G.V.; Stuart, C.R.

1997-01-01

Here, we investigate the effects of oxygen on the radiation chemistry of hydrazine at elevated temperatures. The chemistry of this system is important to reactor coolant chemistry, particularly under start-up conditions when hydrazine is added to suppress corrosion which would otherwise be caused by the ingress of oxygen. The radiation chemistry of aqueous solutions of hydrazine has been investigated previously in the presence of oxygen by Ershov et al., but only at room temperature. In those experiments, both steady-state γ-radiolysis and pulse radiolysis were used to deduce the mechanism of decomposition of hydrazine in the presence of oxygen. (author)

Enhanced biodegradation of methylhydrazine and hydrazine contaminated NASA wastewater in fixed-film bioreactor.

Science.gov (United States)

Nwankwoala, A U; Egiebor, N O; Nyavor, K

2001-01-01

The aerobic biodegradation of National Aeronautics and Space Administration (NASA) wastewater that contains mixtures of highly concentrated methylhydrazine/hydrazine, citric acid and their reaction product was studied on a laboratory-scale fixed film trickle-bed reactor. The degrading organisms, Achromobacter sp., Rhodococcus B30 and Rhodococcus J10, were immobilized on coarse sand grains used as support-media in the columns. Under continuous flow operation, Rhodococcus sp. degraded the methylhydrazine content of the wastewater from a concentration of 10 to 2.5 mg/mL within 12 days and the hydrazine from approximately 0.8 to 0.1 mg/mL in 7 days. The Achromobacter sp. was equally efficient in degrading the organics present in the wastewater, reducing the concentration of the methylhydrazine from 10 to approximately 5 mg/mL within 12 days and that of the hydrazine from approximately 0.8 to 0.2 mg/mL in 7 days. The pseudo first-order rate constants of 0.137 day(-1) and 0.232 day(-1) were obtained for the removal of methylhydrazine and hydrazine, respectively, in wastewater in the reactor column. In the batch cultures, rate constants for the degradation were 0.046 and 0.079 day(-1) for methylhydrazine and hydrazine respectively. These results demonstrate that the continuous flow bioreactor afford greater degradation efficiencies than those obtained when the wastewater was incubated with the microbes in growth-limited batch experiments. They also show that wastewater containing hydrazine is more amenable to microbial degradation than one that is predominant in methylhydrazine, in spite of the longer lag period observed for hydrazine containing wastewater. The influence of substrate concentration and recycle rate on the degradation efficiency is reported. The major advantages of the trickle-bed reactor over the batch system include very high substrate volumetric rate of turnover, higher rates of degradation and tolerance of the 100% concentrated NASA wastewater. The

Feasibility of a responsive, hybrid propulsion augmented, Vertical-Takeoff-and-Landing, Single-Stage-to-Orbit launch system

Science.gov (United States)

Pelaccio, Dennis G.

1996-03-01

A novel, reusable, Vertical-Takeoff-and-Landing, Single-Stage-to-Orbit (VTOL/SSTO) launch system concept, named HYP-SSTO, is presented in this paper. This launch vehicle system concept uses a highly coupled, main high performance liquid oxygen/liquid hydrogen (LOX/LH2) propulsion system, that is used only for launch, with a hybrid auxiliary propulsion system which is used during final orbit insertion, major orbit maneuvering, and landing propulsive burn phases of flight. By using a hybrid propulsion system for major orbit maneuver burns and landing, this launch system concept has many advantages over conventional VTOL/SSTO concepts that use LOX/LH2 propulsion system(s) burns for all phases of flight. Because hybrid propulsion systems are relatively simple and inert by their nature, this concept has the potential to support short turnaround times between launches, be economical to develop, and be competitive in terms of overall system life-cycle cost. This paper provides a technical description of the novel, reusable HYP-SSTO launch system concept. Launch capability performance, as well as major design and operational system attributes, are identified and discussed.

Proposed amendment to the final decision document for the hydrazine blending and storage facility, interim response action

Energy Technology Data Exchange (ETDEWEB)

1991-02-25

From April through August 1989, a bench-/pilot-scale testing program was conducted to evaluate whether qualified manufactures of ultraviolet (UV)/chemical oxidation equipment could reduce the concentrations of hydrazine fuel compounds (hydrazine, monomethyl hydrazine (MMH), and unsymmetrical dimethyl hydrazine (UDMH)) and n-nitrosodimethylamine (NDMA) in the wastewater to action levels identified in the Final Decision Document. A secondary objective of this testing program was to generate design and operational information for use during the full-scale startup program.

Hydrazine in the Ugi Tetrazole Reaction

NARCIS (Netherlands)

Patil, Pravin; Zhang, Ji; Kurpiewska, Katarzyna; Kalinowska-Tłuścik, Justyna; Dömling, Alexander

2016-01-01

We describe the hitherto unknown use of N-Boc-protected hydrazine in the Ugi tetrazole reaction to access a library of highly substituted 5-(hydrazinomethyl)-1-methyl-1H-tetrazoles. The reaction is very versatile and good to high yielding. A one-pot, two-step procedure is given.

Developing a New Sampling And Analysis Method For Hydrazine And Monomethyl Hydrazine: Using a Derivatizing Agent With Solid Phase Microextraction

Science.gov (United States)

Allen, John

2001-01-01

Solid phase microextraction (SPME) will be used to develop a method for detecting monomethyl hydrazine (MMH) and hydrazine (Hz). A derivatizing agent, pentafluorobenzoyl chloride (PFBCI), is known to react readily with MMH and Hz. The SPME fiber can either be coated with PFBCl and introduced into a gaseous stream containing MMH, or PFBCl and MMH can react first in a syringe barrel and after a short equilibration period a SPME is used to sample the resulting solution. These methods were optimized and compared. Because Hz and MMH can degrade the SPME, letting the reaction occur first gave better results. Only MMH could be detected using either of these methods. Future research will concentrate on constructing calibration curves and determining the detection limit.

Isolation of N-linked glycopeptides by hydrazine-functionalized magnetic particles.

Science.gov (United States)

Sun, Shisheng; Yang, Ganglong; Wang, Ting; Wang, Qinzhe; Chen, Chao; Li, Zheng

2010-04-01

We introduce a novel combination of magnetic particles with hydrazine chemistry, dubbed as hydrazine-functionalized magnetic particles (HFMP) for isolation of glycopeptides. Four methods have been developed and compared for the production of HFMP by hydrazine modification of the surface of the carboxyl and epoxy-silanized magnetic particles, respectively. The evaluation of the capability and specificity of HFMP as well as the optimization of the coupling condition for capturing of glycoproteins were systematically investigated. The results showed that HFMP prepared by adipic dihydrazide functionalization from carboxyl-silanized magnetic particles (HFCA) displayed the maximum capture capacity and isolated efficiency for glycoprotein. When measured with glycoproteins, the capacity of the HFCA (1 g) for coupling bovine fetuin was 130 +/- 5.3 mg. The capability of this method was also confirmed by successful isolation of all formerly glycosylated peptides from standard glycoproteins and identification of their glycosylation sites, which demonstrated the feasibility of the HFCA as an alternative solid support for isolation of glycoproteins/glycopeptides.

A chromogenic and fluorogenic rhodol-based chemosensor for hydrazine detection and its application in live cell bioimaging

Science.gov (United States)

Tiensomjitr, Khomsan; Noorat, Rattha; Chomngam, Sinchai; Wechakorn, Kanokorn; Prabpai, Samran; Kanjanasirirat, Phongthon; Pewkliang, Yongyut; Borwornpinyo, Suparerk; Kongsaeree, Palangpon

2018-04-01

A rhodol-based fluorescent probe has been developed as a selective hydrazine chemosensor using levulinate as a recognition site. The rhodol levulinate probe (RL) demonstrated high selectivity and sensitivity toward hydrazine among other molecules. The chromogenic response of RL solution to hydrazine from colorless to pink could be readily observed by the naked eye, while strong fluorescence emission could be monitored upon excitation at 525 nm. The detection process occurred via a ring-opening process of the spirolactone initiated by hydrazinolysis, triggering the fluorescence emission with a 53-fold enhancement. The probe rapidly reacted with hydrazine in aqueous medium with the detection limit of 26 nM (0.83 ppb), lower than the threshold limit value (TLV) of 10 ppb suggested by the U.S. Environmental Protection Agency. Furthermore, RL-impregnated paper strips could detect hydrazine vapor. For biological applicability of RL, its membrane-permeable property led to bioimaging of hydrazine in live HepG2 cells by confocal fluorescence microscopy.

Crystal structures of nitrato-(2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) aquacopper and chloro-(2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) copper

Energy Technology Data Exchange (ETDEWEB)

Chumakov, Yu. M. [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Paholnitcaia, A. Yu. [State University of Moldova (Moldova, Republic of); Petrenko, P. A. [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Tsapkov, V. I., E-mail: vtsapkov@gmail.com [State University of Moldova (Moldova, Republic of); Poirier, D. [Centre Hospitalier Universitaire de Quebec (Canada); Gulea, A. P. [State University of Moldova (Moldova, Republic of)

2015-01-15

Two crystal modifications of nitrato-(2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) aquacopper (I and II) and two modifications of chloro-(2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) copper (III and IV) have been synthesized and studied by X-ray diffraction. In structures I and II, the copper atoms coordinate a monodeprotonated molecule of the organic ligand, nitrate ions, and a water molecule. In crystals of I, the complexes are monomeric, whereas complexes II are linked via nitrate ions to form polymeric chains. In both structures the coordination polyhedron of the copper atom can be described as a distorted tetragonal bipyramid—(4 + 1 + 1) in I and (4 + 2) in II. These coordination polyherdra have different compositions. In structures III and IV, the metal atoms coordinate a monodeprotonated (2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazole molecule and chloride ions. In III the complex-forming ion has square-planar coordination geometry, whereas structure IV consists of centrosymmetric dimers with two bridging chlorine atoms. It was found that nitrato-(2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) aquacopper possesses antitumor activity.

Synthesis and structural studies of Cp{sup *} rhodium and Cp{sup *} iridium complexes of picolinic hydrazine ligand

Energy Technology Data Exchange (ETDEWEB)

Palepu, Narasinga Rao; Kollipara, Mohan Rao [Centre for Advanced Studies in Chemistry, North-Eastern Hill University, Shillong (India); Kaminsky Werner [Dept. of Chemistry, University of Washington, Seattle (United States)

2017-01-15

A series of Cp{sup *}Rh and Cp{sup *}Ir complexes of picolinic hydrazine ligand are synthesized and characterized. Picolinic hydrazine has yielded only dinuclear complexes in the case of rhodium metal whereas both mono and dinuclear complexes with iridium metal. Iridium complexes are formed as quaternary salts by the migration of the N–H proton onto the adjacent amine group of the hydrazine after binding to the metal. Picolinic hydrazine acts as nitrogen and oxygen donor ligand in the form of bi and tetradentate bonding modes.

Auxiliary cooling device for power plant

International Nuclear Information System (INIS)

Yamanoi, Kozo.

1996-01-01

An auxiliary cooling sea water pipeline for pumping up cooling sea water, an auxiliary cooling sea water pipeline and a primary side of an auxiliary cooling heat exchanger are connected between a sea water taking vessel and a sea water discharge pit. An auxiliary cooling water pump is connected to an auxiliary water cooling pipeline on the second side of the auxiliary cooling heat exchanger. The auxiliary cooling water pipeline is connected with each of auxiliary equipments of a reactor system and each of auxiliary equipments of the turbine system connected to a turbine auxiliary cooling water pipeline in parallel. During ordinary operation of the reactor, heat exchange for each of the auxiliary equipments of the reactor and heat exchange for each of the equipments of the turbine system are conducted simultaneously. Since most portions of the cooling devices of each of the auxiliary equipments of the reactor system and each of the auxiliary equipments of the turbine system can be used in common, the operation efficiency of the cooling device is improved. In addition, the space for the pipelines and the cost for the equipments can be reduced. (I.N.)

Interactions of Hydrazine and of Hydrazine Derivatives with Soil Constituents and with Soils

Science.gov (United States)

1984-08-23

the amount of hydrazine adsorbed per meq of A1 3+ was nearly thrice as inch for kaolinite (420 Peq me - 1 ) than for montmorillonite (150 peg -1) showing...1952) Absorption (cm ) Assignment Vapour Liquid 3350 3338 N-H stretching 3325 3314 3280 3200 1628 N-H bending 1587 1493 1275 1280 Table 15 IR spectra of...contrast, the spectrum of the monomethylhydrazine-clay complex when treated in a similar way, still included an absorption at 3350 cm 1 which assigned to

Green Application for Space Power

Science.gov (United States)

Robinson, Joel

2015-01-01

Most space vehicle auxiliary power units (APUs) use hydrazine propellant for generating power. Hydrazine is a toxic, hazardous fuel that requires special safety equipment and processes for handling and loading. In recent years, there has been development of two green propellants (less toxic) that could enable their use in APUs. The Swedish government, in concert with the Swedish Space Corporation, has developed a propellant based on ammonium dinitramide (LMP-103S) that was flown on the Prisma spacecraft in 2010. The United States Air Force (USAF) has been developing a propellant based on hydroxylammonium nitrate (AFM315E) that is scheduled to fly on the Green Propellant Infusion Mission in the spring of 2016 to demonstrate apogee and reaction control thrusters. However, no one else in the Agency is currently pursuing use of green propellants for application to the APUs. Per the TA-01 Launch Propulsion Roadmap, the Space Technology Mission Directorate had identified the need to have a green propellant APU by 2015. This is our motivation for continuing activities.

Cyclic voltammetry deposition of copper nanostructure on MWCNTs modified pencil graphite electrode: An ultra-sensitive hydrazine sensor

Energy Technology Data Exchange (ETDEWEB)

Heydari, Hamid [Faculty of Sciences, Razi University, Kermanshah (Iran, Islamic Republic of); Gholivand, Mohammad B., E-mail: mbgholivand@razi.ac.ir [Faculty of Sciences, Razi University, Kermanshah (Iran, Islamic Republic of); Abdolmaleki, Abbas [Department of Chemistry, Malek Ashtar University of Technology, Tehran (Iran, Islamic Republic of)

2016-09-01

In this study, Copper (Cu) nanostructures (CuNS) were electrochemically deposited on a film of multiwall carbon nanotubes (MWCNTs) modified pencil graphite electrode (MWCNTs/PGE) by cyclic voltammetry method to fabricate a CuNS–MWCNTs composite sensor (CuNS–MWCNT/PGE) for hydrazine detection. Scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) were used for the characterization of CuNS on the MWCNTs matrix. The composite of CuNS-MWCNTs was characterized with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The preliminary studies showed that the proposed sensor have a synergistic electrocatalytic activity for the oxidation of hydrazine in phosphate buffer. The catalytic currents of square wave voltammetry had a linear correlation with the hydrazine concentration in the range of 0.1 to 800 μM with a low detection limit of 70 nM. Moreover, the amperometric oxidation current exhibited a linear correlation with hydrazine concentration in the concentration range of 50–800 μM with the detection limit of 4.3 μM. The proposed electrode was used for the determination of hydrazine in real samples and the results were promising. Empirical results also indicated that the sensor had good reproducibility, long-term stability, and the response of the sensor to hydrazine was free from interferences. Moreover, the proposed sensor benefits from simple preparation, low cost, outstanding sensitivity, selectivity, and reproducibility for hydrazine determination. - Highlights: • The Copper nanostructures (CuNS) were prepared by cyclic voltammetry deposition. • The CuNS-MWCNT/PGE sensor shows high activity toward hydrazine (N{sub 2}H{sub 4}). • The proposed sensor exhibits a wide linear range (0.1 to 800 μM), low detection limit (70 nM), high sensitivity and stability for hydrazine.

Comparative metabonomics of differential hydrazine toxicity in the rat and mouse

International Nuclear Information System (INIS)

Bollard, Mary E.; Keun, Hector C.; Beckonert, Olaf; Ebbels, Tim M.D.; Antti, Henrik; Nicholls, Andrew W.; Shockcor, John P.; Cantor, Glenn H.; Stevens, Greg; Lindon, John C.; Holmes, Elaine; Nicholson, Jeremy K.

2005-01-01

Interspecies variation between rats and mice has been studied for hydrazine toxicity using a novel metabonomics approach. Hydrazine hydrochloride was administered to male Sprague-Dawley rats (30 mg/kg, n = 10 and 90 mg/kg, n = 10) and male B6C3F mice (100 mg/kg, n = 8 and 250 mg/kg, n = 8) by oral gavage. In each species, the high dose was selected to produce the major histopathologic effect, hepatocellular lipid accumulation. Urine samples were collected at sequential time points up to 168 h post dose and analyzed by 1 H NMR spectroscopy. The metabolites of hydrazine, namely diacetyl hydrazine and 1,4,5,6-tetrahydro-6-oxo-3-pyridazine carboxylic acid (THOPC), were detected in both the rat and mouse urine samples. Monoacetyl hydrazine was detected only in urine samples from the rat and its absence in the urine of the mouse was attributed to a higher activity of N-acetyl transferases in the mouse compared with the rat. Differential metabolic effects observed between the two species included elevated urinary β-alanine, 3-D-hydroxybutyrate, citrulline, N-acetylcitrulline, and reduced trimethylamine-N-oxide excretion unique to the rat. Metabolic principal component (PC) trajectories highlighted the greater degree of toxic response in the rat. A data scaling method, scaled to maximum aligned and reduced trajectories (SMART) analysis, was used to remove the differences between the metabolic starting positions of the rat and mouse and varying magnitudes of effect, to facilitate comparison of the response geometries between the rat and mouse. Mice followed 'biphasic' open PC trajectories, with incomplete recovery 7 days after dosing, whereas rats followed closed 'hairpin' time profiles, indicating functional reversibility. The greater magnitude of metabolic effects observed in the rat was supported by the more pronounced effect on liver pathology in the rat when compared with the mouse

Enthalpy of Formation of N ₂ H ₄ (Hydrazine) Revisited

Energy Technology Data Exchange (ETDEWEB)

Feller, David [Department; Bross, David H. [Chemical; Ruscic, Branko [Chemical; Computation

2017-08-02

In order to address the accuracy of the long-standing experimental enthalpy of formation of gas-phase hydrazine, fully confirmed in earlier versions of Active Thermochemical Tables (ATcT), the provenance of that value is re-examined in light of new high-end calculations of the Feller-Peterson-Dixon (FPD) variety. An overly optimistic determination of the vaporization enthalpy of hydrazine, which created an unrealistically strong connection between the gas phase thermochemistry and the calorimetric results defining the thermochemistry of liquid hydrazine was identified as the probable culprit. The new enthalpy of formation of gas-phase hydrazine, based on balancing all available knowledge, was determined to be 111.57 ± 0.47 kJ/mol at 0 K (97.41 kJ/mol at 298.15 K). Close agreement was found between the ATcT (even excluding the latest theoretical result) and FPD enthalpies.

The Acquisition of Auxiliary Syntax: A Longitudinal Elicitation Study. Part 1: Auxiliary BE

Science.gov (United States)

Theakston, Anna L.; Rowland, Caroline F.

2009-01-01

Purpose: The question of how and when English-speaking children acquire auxiliaries is the subject of extensive debate. Some researchers posit the existence of innately given Universal Grammar principles to guide acquisition, although some aspects of the auxiliary system must be learned from the input. Others suggest that auxiliaries can be…

Auxiliary buildings

International Nuclear Information System (INIS)

Lakner, I.; Lestyan, E.

1979-01-01

The nuclear power station represents a complicated and a particular industrial project. Consequently, the design of the auxiliary buildings serving the power station (offices, kitchen, refreshment room, workshops, depots, water treatment plant building, boiler houses, etc.) requires more attention than usual. This chapter gives a short survey of the auxiliary buildings already completed and discusses the problems of their design, location and structure. (author)

Metabolomics of Hydrazine-Induced Hepatotoxicity in Rats for Discovering Potential Biomarkers

Directory of Open Access Journals (Sweden)

Zhuoling An

2018-01-01

Full Text Available Metabolic pathway disturbances associated with drug-induced liver injury remain unsatisfactorily characterized. Diagnostic biomarkers for hepatotoxicity have been used to minimize drug-induced liver injury and to increase the clinical safety. A metabolomics strategy using rapid-resolution liquid chromatography/tandem mass spectrometry (RRLC-MS/MS analyses and multivariate statistics was implemented to identify potential biomarkers for hydrazine-induced hepatotoxicity. The global serum and urine metabolomics of 30 hydrazine-treated rats at 24 or 48 h postdosing and 24 healthy rats were characterized by a metabolomics approach. Multivariate statistical data analyses and receiver operating characteristic (ROC curves were performed to identify the most significantly altered metabolites. The 16 most significant potential biomarkers were identified to be closely related to hydrazine-induced liver injury. The combination of these biomarkers had an area under the curve (AUC > 0.85, with 100% specificity and sensitivity, respectively. This high-quality classification group included amino acids and their derivatives, glutathione metabolites, vitamins, fatty acids, intermediates of pyrimidine metabolism, and lipids. Additionally, metabolomics pathway analyses confirmed that phenylalanine, tyrosine, and tryptophan biosynthesis as well as tyrosine metabolism had great interactions with hydrazine-induced liver injury in rats. These discriminating metabolites might be useful in understanding the pathogenesis mechanisms of liver injury and provide good prospects for drug-induced liver injury diagnosis clinically.

Hydrazine levels in formulations of hydralazine, isoniazid, and phenelzine over a 2-year period.

Science.gov (United States)

Lovering, E G; Matsui, F; Curran, N M; Robertson, D L; Sears, R W

1983-08-01

Hydrazine levels in formulations of hydralazine, isoniazid, and phenelzine have been measured over a 2-year period under ambient conditions and under temperature and humidity stress. Hydralazine tablets are stable under ambient conditions, but the hydrazine level in an injectable formulation increased from 4.5 to 10 micrograms/ml over a 23-month period. Isoniazid tablets are also stable, but hydrazine levels in an elixir and a pyridoxine combination product doubled to 44 micrograms/ml and 19 micrograms/tablet, respectively. Levels in phenelzine tablets appeared to remain constant at approximately 60 micrograms/tablet, with considerable tablet-to-tablet variation.

Ultra-high sensitive hydrazine chemical sensor based on low-temperature grown ZnO nanoparticles

International Nuclear Information System (INIS)

Mehta, S.K.; Singh, Kulvinder; Umar, Ahmad; Chaudhary, G.R.; Singh, Sukhjinder

2012-01-01

Graphical abstract: Systematic representation of the fabricated amperometric hydrazine chemical sensor based on ZnO NPs/Au modified electrode. Highlights: ► Synthesis of well-crystalline ZnO NPs has been achieved in aqueous solution. ► ZnO NPs act as efficient electron mediators for hydrazine sensor. ► Extremely high sensitivity and low-detection limit have been obtained. - Abstract: Using well-crystalline ZnO nanoparticles (NPs), an ultra high sensitive hydrazine amperometric sensor has been fabricated and reported in this paper. The ZnO NPs have been synthesized by very simple aqueous solution process at 90 °C and characterized in detail in terms of their morphological, compositional, structural and optical properties. The detailed investigations reveal that the synthesized products are well-crystalline NPs, possessing wurtzite hexagonal phase and exhibit good optical properties. The fabricated amperometric hydrazine sensor exhibits ultra-high sensitivity of ∼97.133 μA cm −2 μM −1 and very low-detection limit of 147.54 nM. To the best of our knowledge, this is the first report in which an ultra-high sensitivity and low-detection limit have been obtained for the hydrazine chemical sensor based on ZnO nanostructures.

Auxiliary verbs in Dinka

DEFF Research Database (Denmark)

Andersen, Torben

2007-01-01

Dinka, a Western Nilotic language, has a class of auxiliary verbs which is remarkable in the following four respects: (i) It is unusually large, comprising some 20 members; (ii) it is grammatically homogeneous in terms of both morphology and syntax; (iii) most of the auxiliary verbs correspond...... to adverbs in languages like English, while the rest are tense-aspect markers; and (iv) it is possible to combine several auxiliary verbs in a single clause. For some of the auxiliary verbs there are extant full verbs from which they have evolved. To some extent, therefore, it is possible to observe what...

Effect of hydrazine on general corrosion of carbon and low-alloyed steels in pressurized water reactor secondary side water

Energy Technology Data Exchange (ETDEWEB)

Järvimäki, Sari [Fortum Ltd, Loviisa Power Plant, Loviisa (Finland); Saario, Timo; Sipilä, Konsta [VTT Technical Research Centre of Finland Ltd., Nuclear Safety, P.O. Box 1000, FIN-02044 VTT (Finland); Bojinov, Martin, E-mail: martin@uctm.edu [Department of Physical Chemistry, University of Chemical Technology and Metallurgy, Kl. Ohridski Blvd, 8, 1756 Sofia (Bulgaria)

2015-12-15

Highlights: • The effect of hydrazine on the corrosion of steel in secondary side water investigated by in situ and ex situ techniques. • Oxide grown on steel in 100 ppb hydrazine shows weaker protective properties – higher corrosion rates. • Possible explanation of the accelerating effect of higher concentrations of hydrazine on flow assisted corrosion offered. - Abstract: The effect of hydrazine on corrosion rate of low-alloyed steel (LAS) and carbon steel (CS) was studied by in situ and ex situ techniques under pressurized water reactor secondary side water chemistry conditions at T = 228 °C and pH{sub RT} = 9.2 (adjusted by NH{sub 3}). It is found that hydrazine injection to a maximum level of 5.06 μmol l{sup −1} onto surfaces previously oxidized in ammonia does not affect the corrosion rate of LAS or CS. This is confirmed also by plant measurements at Loviisa NPP. On the other hand, hydrazine at the level of 3.1 μmol l{sup −1} decreases markedly the amount and the size of deposited oxide crystals on LAS and CS surface. In addition, the oxide grown in the presence of 3.1 μmol l{sup −1} hydrazine is somewhat less protective and sustains a higher corrosion rate compared to an oxide film grown without hydrazine. These observations could explain the accelerating effect of higher concentrations of hydrazine found in corrosion studies of LAS and CS.

Control and management of the chemical risk linked with hydrazine hydrate storage, unloading and injection across French nuclear fleet

International Nuclear Information System (INIS)

Spahic, Mersiha; Dzemidzic Aida; Dijoux, Michel; Pages, Danielle; Rigal, Jean-Francois; Boize, Magali

2012-09-01

Across the EDF nuclear fleet, the chemical risk linked with hydrazine hydrate storage, unloading and injection has received much attention in the past decades. Since 1997, continuous investigation into the substitution of dangerous and carcinogenic chemicals has been conducted and regularly updated by EDF. As a downstream user of hydrazine hydrate, EDF is concerned by REACH legislation, in force since 1 June 2007. As part of the compliance process with REACH, EDF provided its hydrazine hydrate suppliers with information regarding the uses of the chemical. This was done by the end of 2008, as per REACH deadline. On the other hand, EDF contributed throughout European Chemicals Agency consultation phase by submitting data relating to hydrazine hydrate uses across nuclear sites. The absence of a suitable hydrazine hydrate replacement product, able to satisfy the entirety of technical requirements, entails rigorous arrangements to be implemented in order to segregate the zones where use of hydrazine is made and therefore eradicate the risk to personnel regarding hydrazine effects. Consequently, a number of engineering changes and modifications are to be carried out on the chemical injection systems of 58 French nuclear power plants over the next few years as part of the EDF Hydrazine Fleet Programme. (authors)

Determination of hydrazine in technological waters of power plants

International Nuclear Information System (INIS)

Novak, M.; Hlatky, J.; Santova, E.; Nadasky, A.

1991-01-01

The available commercial automatic analyzers for the determination of hydrazine with spectrophotometric detection are described. Analyzers that are manufactured at present in Czechoslovakia can be divided into two groups. The first group involves the commercially available UPFA IV NH industrial analyzer. Experience in the introduction of this analyzer in the conditions of the nuclear power plant secondary circuit bear out the earlier observation of failures in the injection and dispensing of reagents and frequent failures of the mechanical programmer. For the determination of hydrazine, the reagent was dissolved in sulfuric acid, and in a time the analyzer had to be put out of operation due to corrosion problems. A remedy consists in the replacement of sulfuric acid with the less aggressive oxalic acid. Another group of automatic analyzers for the determination of hydrazine is based on the flow injection analysis (FIA) method. Although exhibiting a high throughput, analyzers of this kind put high demands on the purity of reagents. The instruments are better suited to laboratory work, whereas problems can arise in industrial conditions. Based on experience gained in the use of automatic analyzers of the two groups, two new analyzers were designed. The one is based on the flow analysis principle and is of modular design, whereas the other is based on the stopped-flow FIA principle; an adapted flow cell is accommodated in the detector, and the device uses a hydraulic path whose diameter is 2 to 5 mm. The determination of hydrazine occurs in a closed system, the reagent being protected from contact with air; this extends the lifetime of the facility and minimizes personnel exposure to toxic and/or radioactive substances. (author). 5 figs., 2 tabs., 8 refs

Electroless plating of Ni–B film as a binder-free highly efficient electrocatalyst for hydrazine oxidation

Energy Technology Data Exchange (ETDEWEB)

Wen, Xiao-Ping; Dai, Hong-Bin, E-mail: mshbdai@scut.edu.cn; Wu, Lin-Song; Wang, Ping, E-mail: mspwang@scut.edu.cn

2017-07-01

Graphical abstract: A Ni–B film was grown on Ni foam to form a binder-free highly efficient electrocatalyst for hydrazine oxidation in alkaline medium. The newly-developed Ni–B/Ni foam electrocatalyst may promote the practical application of hydrazine as a viable energy carrier for fuel cells. - Highlights: • A Ni–B film grown on Ni foam electrocatalyst is prepared by the electrless plating. • The Ni–B film shows high activity and stability for N{sub 2}H{sub 4} electrooxidation reaction. • The improved catalytic property is ascribed to B-tuned electronic structure of Ni. • The resultant catalyst may promote application of N{sub 2}H{sub 4} as a viable energy carrier. - Abstract: Hydrazine is a promising energy carrier for fuel cells owing to its combined advantages of high theoretical cell voltage, high-power density, and no greenhouse gas emission. By using an electroless plating process, we have prepared a robust Ni–B film grown on Ni foam that is highly effective for hydrazine electrooxidation in alkaline media. The effects of reaction temperature, concentrations of hydrous hydrazine and sodium hydroxide in the fuel solution on performance of hydrazine electrooxidation reaction are investigated. The mechanistic reason for the property advantage of as-prepared Ni–B/Ni foam catalyst over the relevant catalysts is discussed based on careful kinetics studies and characterization. The facile synthesis of Ni-based catalyst with high activity and good stability is of clear significance for the development of hydrous hydrazine as a viable energy carrier.

Electroless plating of Ni–B film as a binder-free highly efficient electrocatalyst for hydrazine oxidation

International Nuclear Information System (INIS)

Wen, Xiao-Ping; Dai, Hong-Bin; Wu, Lin-Song; Wang, Ping

2017-01-01

Graphical abstract: A Ni–B film was grown on Ni foam to form a binder-free highly efficient electrocatalyst for hydrazine oxidation in alkaline medium. The newly-developed Ni–B/Ni foam electrocatalyst may promote the practical application of hydrazine as a viable energy carrier for fuel cells. - Highlights: • A Ni–B film grown on Ni foam electrocatalyst is prepared by the electrless plating. • The Ni–B film shows high activity and stability for N_2H_4 electrooxidation reaction. • The improved catalytic property is ascribed to B-tuned electronic structure of Ni. • The resultant catalyst may promote application of N_2H_4 as a viable energy carrier. - Abstract: Hydrazine is a promising energy carrier for fuel cells owing to its combined advantages of high theoretical cell voltage, high-power density, and no greenhouse gas emission. By using an electroless plating process, we have prepared a robust Ni–B film grown on Ni foam that is highly effective for hydrazine electrooxidation in alkaline media. The effects of reaction temperature, concentrations of hydrous hydrazine and sodium hydroxide in the fuel solution on performance of hydrazine electrooxidation reaction are investigated. The mechanistic reason for the property advantage of as-prepared Ni–B/Ni foam catalyst over the relevant catalysts is discussed based on careful kinetics studies and characterization. The facile synthesis of Ni-based catalyst with high activity and good stability is of clear significance for the development of hydrous hydrazine as a viable energy carrier.

Synthesis, characterization and antioxidant study of N,N’-bis(2-chlorobenzamidothiocarbonyl)hydrazine

Energy Technology Data Exchange (ETDEWEB)

Firdausiah, Syadza; Hasbullah, Siti Aishah; Yamin, Bohari M. [School of Chemical Science and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

2015-09-25

N,N’-bis(2-chlorobenzamidothiocarbonyl)hydrazine was synthesized from 2-chlorobenzoylisothiocyanate and hydrazine in acetone. The compound was characterized by infrared, {sup 1}H and {sup 13}C NMR, and UV-Vis spectroscopies. X-ray crystallography study showed the molecule adopt trans configuration at both N-N and C-N bonds. The compound showed high antioxidant activity, EC{sub 50} of 374.89 µM, compared to ascorbic acid (EC{sub 50} of 561.36 µM)

Enthalpies of Formation of Hydrazine and Its Derivatives.

Science.gov (United States)

Dorofeeva, Olga V; Ryzhova, Oxana N; Suchkova, Taisiya A

2017-07-20

Enthalpies of formation, Δ f H 298 ° , in both the gas and condensed phase, and enthalpies of sublimation or vaporization have been estimated for hydrazine, NH 2 NH 2 , and its 36 various derivatives using quantum chemical calculations. The composite G4 method has been used along with isodesmic reaction schemes to derive a set of self-consistent high-accuracy gas-phase enthalpies of formation. To estimate the enthalpies of sublimation and vaporization with reasonable accuracy (5-20 kJ/mol), the method of molecular electrostatic potential (MEP) has been used. The value of Δ f H 298 ° (NH 2 NH 2 ,g) = 97.0 ± 3.0 kJ/mol was determined from 75 isogyric reactions involving about 50 reference species; for most of these species, the accurate Δ f H 298 ° (g) values are available in Active Thermochemical Tables (ATcT). The calculated value is in excellent agreement with the reported results of the most accurate models based on coupled cluster theory (97.3 kJ/mol, the average of six calculations). Thus, the difference between the values predicted by high-level theoretical calculations and the experimental value of Δ f H 298 ° (NH 2 NH 2 ,g) = 95.55 ± 0.19 kJ/mol recommended in the ATcT and other comprehensive reference sources is sufficiently large and requires further investigation. Different hydrazine derivatives have been also considered in this work. For some of them, both the enthalpy of formation in the condensed phase and the enthalpy of sublimation or vaporization are available; for other compounds, experimental data for only one of these properties exist. Evidence of accuracy of experimental data for the first group of compounds was provided by the agreement with theoretical Δ f H 298 ° (g) value. The unknown property for the second group of compounds was predicted using the MEP model. This paper presents a systematic comparison of experimentally determined enthalpies of formation and enthalpies of sublimation or vaporization with the results of

Morpho-functional Blood Changes Under the Influence of Hydrazine and Correction with “Salsokollin” Drug

Directory of Open Access Journals (Sweden)

Marat R. Khanturin

2012-09-01

Full Text Available Hydrazine derivatives are used in different areas: airspace industry, healthcare, laboratory-diagnostic activity, that’s why the environment is subjected to contamination by hydrazines. For Kazakhstan, which houses the "Baikonur" Cosmodrome, the problem of environmental pollution by rocket fuel and its components is a burning issue nowadays. This article deals with the impacts by industrial hydrazines on biochemical data of the blood and its correction with the “Salsokollin” Drug. The samples of bilirubin, the whole protein, urea, creatinine, cholesterol, glucose, aminotransferase a-amylases, α-amylase were taken. The thymol test was carried out.

Electrodeposited nano-scale islands of ruthenium oxide as a bifunctional electrocatalyst for simultaneous catalytic oxidation of hydrazine and hydroxylamine

Energy Technology Data Exchange (ETDEWEB)

Zare, Hamid R., E-mail: hrzare@yazduni.ac.ir [Department of Chemistry, Yazd University, P.O. Box 89195-741, Yazd (Iran, Islamic Republic of); Nanotechnology Research Center, Yazd University, P.O. Box 89195-741, Yazd (Iran, Islamic Republic of); Hashemi, S. Hossein; Benvidi, Ali [Department of Chemistry, Yazd University, P.O. Box 89195-741, Yazd (Iran, Islamic Republic of)

2010-06-04

For the first time, an electrodeposited nano-scale islands of ruthenium oxide (ruthenium oxide nanoparticles), as an excellent bifunctional electrocatalyst, was successfully used for hydrazine and hydroxylamine electrocatalytic oxidation. The results show that, at the present bifunctional modified electrode, two different redox couples of ruthenium oxides serve as electrocatalysts for simultaneous electrocatalytic oxidation of hydrazine and hydroxylamine. At the modified electrode surface, the peaks of differential pulse voltammetry (DPV) for hydrazine and hydroxylamine oxidation were clearly separated from each other when they co-exited in solution. Thus, it was possible to simultaneously determine hydrazine and hydroxylamine in the samples at a ruthenium oxide nanoparticles modified glassy carbon electrode (RuON-GCE). Linear calibration curves were obtained for 2.0-268.3 {mu}M and 268.3-417.3 {mu}M of hydrazine and for 4.0-33.8 {mu}M and 33.8-78.3 {mu}M of hydroxylamine at the modified electrode surface using an amperometric method. The amperometric method also exhibited the detection limits of 0.15 {mu}M and 0.45 {mu}M for hydrazine and hydroxylamine respectively. RuON-GCE was satisfactorily used for determination of spiked hydrazine in two water samples. Moreover, the studied bifunctional modified electrode exhibited high sensitivity, good repeatability, wide linear range and long-term stability.

Synthesis, structurale elucidation and antioxidant study of Ortho-substituted N,N’-bis(benzamidothiocarbonyl)hydrazine derivatives

Science.gov (United States)

Firdausiah, Syadza; Hasbullah, S. A.; Yamin, B. M.

2018-03-01

Some bis(thiourea) compounds have been reported to posses excellent performance in pharmaceutical and environmental fields because of their ability to form chelating complexes with various anions and metal ions. Structurally for carbonyl thiourea derivatives, to become a chelating agent, it must adopt cis-configuration. In the present study, four new bis(thiourea) derivatives namely N,N’-bis(o-fluorobenzamidothiocarbonyl)hydrazine (1), N,N’- bis(o-chloro-benzamidothiocarbonyl)hydrazine (2), N,N’-bis(o-nitrobenzamidothiocarbonyl)-hydrazine (3), and N,N’-bis(o-methylbenzamidothiocarbonyl)hydrazine (4) were successfully synthesized and characterized by CHNS microelemental analysis, FTIR, UV-Vis, and 1H and 13C NMR spectroscopy. However chemical crystallography study showed that both thiourea moieties in compound (2) and (3) adopt trans geometry. Therefore they are potential monodentate ligand with two active moieties. DPPH radical scavenging experiment showed that compound (1), (2), and (4) exhibited higher antioxidant activity than ascorbic acid (Vitamin C).

Investigation of the direct and indirect electrochemical oxidation of hydrazine in nitric acid medium on platinum; Etude de l`oxydation electrochimique directe et indirecte de l`hydrazine en milieu acide nitrique sur platine

Energy Technology Data Exchange (ETDEWEB)

Cames, B

1997-12-31

In nuclear fuel processing by the PUREX process, the purification of plutonium in nitric acid medium requires the oxidation of Pu(III) to Pu(IV), and of hydrazinium nitrate to nitrogen. The study helped to characterize the electrochemical behavior of the oxidation of hydrazinium nitrate and the reduction of nitric acid to nitrous acid, a compound which can chemically oxidize hydrazinium nitrate and Pu(III). Electro-analytical studies on polycrystalline platinum showed that hydrazine is oxidized in two potential zones, which depend on the surface texture of the platinum anode. Electrolysis in separate compartments, carried out in medium-acid media (2 and 4 mo/l) in the potential zone where these processes take place, showed that, at 0.9 V/ECS, the hydrazine oxidation reactions involved are: a four-electron process (75 %) with nitrogen formation and a one-electron process (25 %) with formation of nitrogen and ammonium ion. By contrast, electrolysis carried out at 0.65 V/ECS (with reactivation of the electrode at - 0.2 V/ECS to remove the poison from the platinum) allowed the selective oxidation of hydrazine to nitrogen by the four-electron reaction. Nitric acid can only be reduced to nitrous acid in the absence of hydrazine. For medium-acid media ({<=} 6 mol/l), this reaction takes place at potentials below - 0.2 V/ECS. However, the production rate of nitrous acid (partial order 0 with respect to nitric acid) is very low compared with the values obtained for strongly-acid media (6 to 10 mol/l) at the potential of - 0.1 V/ECS. Note that, in concentrated nitric medium, the selectivity of the reduction reaction is 47 to 85 % for nitrous acid, depending on the nitric acid concentration (6 to 10 mol/l) and the potential imposed (- 0.1 {<=} E {<=} 0.6 V/ECS). A kinetic study helped to determine the hydrazine oxidation rates as a function of the operating conditions. In all cases, the reaction rate is of partial order 0 with respect to hydrazine. These studies accordingly

Steam generator auxiliary systems

International Nuclear Information System (INIS)

Heinz, A.

1982-01-01

The author deals with damage and defect types obtaining in auxiliary systems of power plants. These concern water/steam auxiliary systems (feed-water tank, injection-control valves, slide valves) and air/fluegas auxiliary systems (blowers, air preheaters, etc.). Operating errors and associated damage are not dealt with; by contrast, weak spots are pointed out which result from planning and design. Damage types and events are collected in statistics in order to facilitate damage evaluation for arriving at improved design solutions. (HAG) [de

Environmental simulation testing of solar cell contamination by hydrazine

Science.gov (United States)

Moore, W. W., Jr.

1972-01-01

Test results for thermal vacuum and radiation environment simulation of hydrazine contamination are discussed. Solar cell performance degradation, measured by short circuit current, is presented in correlation with the variations used in environmental parameters.

Sensitive amperometric determination of hydrazine using a carbon ...

Indian Academy of Sciences (India)

Silver-loaded nanozeolite-L-modified carbon paste electrode (Ag/L–CPE) was used as a novel sensing platform for enhanced electrocatalytic oxidation and determination of hydrazine. Zeolite L nanoparticles were synthesized via hydrothermal approach and then characterized using various techniques such as X-ray ...

CU(II): catalyzed hydrazine reduction of ferric nitrate

International Nuclear Information System (INIS)

Karraker, D.G.

1981-11-01

A method is described for producing ferrous nitrate solutions by the cupric ion-catalyzed reduction of ferric nitrate with hydrazine. The reaction is complete in about 1.5 hours at 40 0 C. Hydrazoic acid is also produced in substantial quantities as a reaction byproduct

Effect of gold nanoparticle as a novel nanocatalyst on luminol-hydrazine chemiluminescence system and its analytical application

International Nuclear Information System (INIS)

Safavi, A.; Absalan, G.; Bamdad, F.

2008-01-01

In this work the catalytic role of unsupported gold nanoparticles on the luminol-hydrazine reaction is investigated. Gold nanoparticles catalyze the reaction of hydrazine and dissolved oxygen to generate hydrogen peroxide and also catalyze the oxidation of luminol by the produced hydrogen peroxide. The result is an intense chemiluminescence (CL) due to the excited 3-aminophthalate anion. In the absence of gold nanoparticles no detectable CL was observed by the reaction of luminol and hydrazine unless an external oxidant is present in the system. The size effect of gold nanoparticles on the CL intensity was investigated. The most intensive CL signals were obtained with 15-nm gold nanoparticles. UV-vis spectra and transmission electron microscopy studies were used to investigate the CL mechanism. The luminol and hydroxide ion concentration, gold nanoparticles size and flow rate were optimized. The proposed method was successfully applied to the determination of hydrazine in boiler feed water samples. Between 0.1 and 30 μM of hydrazine could be determined with a detection limit of 30 nM

METHODOLOGY OF THE HYBRID PROPULSION SYSTEM (DMP & DEP FOR TRIMARAN TYPE FAST PATROL BOAT

Directory of Open Access Journals (Sweden)

Aulia Widyandari

2012-04-01

Full Text Available There are lot of research done to develop a patrol boat, from the modification of hull model until propulsion system equipment. For example the model ship type AMV (Advanced Marine Vehicle was developed starting from the Catamaran, Trimaran and  Pentamaran model. Everything is aimed at obtaining the ship design that has the speed and stability. In addition to achieving high-speed vessel must be equipped with propulsion (Main Power is great, that means the main engine dimensions, auxiliary equipments and fuel tanks is too large. Many Limitations of space on the ship's engine room trimaran vessel is the main obstacle in designing propulsion system. Beside that Patrol boat should have many missions speed, so propulsion system should be designed at that conditions.   Hybrid propulsion is a combination of Diesel Mechanical Propulsion (DMP with Diesel Electric Propulsion (DEP. DMP system is connected directly to the propeller shaft (or through a reduction-gear. DMP has provide more efficiency rate of 95%. While DEP is only able to provide efficiency by 85% - 89% is slightly lower than DMP, but the DEP offers many advantages such as simplicity and suitability in the rotational speed settings, control systems, engine power production Redundancy, Flexibility in the design of equipments layout in engine rooms, noise, vibration and fuel consumption efficiency which affects the lower pollution.   Design of Hybrid Propulsion system can be satisfied and achieved the Power requirements and optimally at all speed condition of patrol boat. Therefore the author made using modeling Maxsurf-11.12 software and carried out various optimization of the choice of main engine, propeller and system conditions for fast patrol boat cruise. 

Thionine-Bromate as a New Reaction System for Kinetic Spectrophotometric Determination of Hydrazine in Cooling Tower Water Samples

Directory of Open Access Journals (Sweden)

Masoud Reza Shishehbore

2013-01-01

Full Text Available A simple, selective, and inexpensive kinetic method was developed for the determination of hydrazine based on its inhibitory effect on the thionine-bromate system in sulfuric acid media. The reaction was monitored spectrophotometrically at 601 nm by a fixed time method. The effect of different parameters such as concentration of reactants, ionic strength, temperature, and time on the rate of reaction was investigated, and the optimum conditions were obtained. Under optimum conditions, the calibration curve was linear in the concentration range from 0.8–23.0 μg mL−1 of hydrazine, and the detection limit of the method was 0.22 μg mL−1. The relative standard deviation for five replicate determinations of 1.0 μg mL−1 of hydrazine was 0.74%. The potential of interfering effect of foreign species on the hydrazine determination was studied. The proposed method was successfully applied for the determination of hydrazine in different water samples.

The development of hydrazine-processed Cu(In,Ga)(Se,S){sub 2} solar cells

Energy Technology Data Exchange (ETDEWEB)

Bob, Brion; Lei, Bao; Chung, Choong-Heui; Yang, Wenbing; Hsu, Wan-Ching; Duan, Hsin-Sheng; Hou, William Wei-Jen; Li, Sheng-Han; Yang, Yang [Department of Materials Science and Engineering, University of California, Los Angeles, CA (United States)

2012-05-15

The hydrazine-based deposition of Cu(In,Ga)(S,Se){sub 2} (CIGS) thin films has attracted considerable attention in recent years due to its potential for the high-throughput production of photovoltaic devices based on this absorber material. This article provides an introduction as well as presenting a complete picture of the current status of hydrazine-based CIGS solar-cell fabrication, including the three major steps of this deposition process: dissolution of the precursor materials in hydrazine, deposition of a film from the resulting precursor solution, and the completion and characterization of a photovoltaic device following absorber deposition. Recent discoveries are then discussed, regarding the dissolution chemistry of the relevant precursor complexes in hydrazine, which together represent the true foundation of this processing method. Recent studies on CIGS film formation are then summarized, including the control and analysis of the crystalline phase, electronic bandgap, and film morphology. Finally, the latest progress in high-performance device fabrication is highlighted, with a focus on optoelectronic characterization including current-voltage, junction capacitance, and minority carrier lifetime measurements. Finally, a discussion and future outlook is provided. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

The CEGB programme on comparative assessment of alternatives to hydrazine for oxygen removal from aqueous systems

International Nuclear Information System (INIS)

Case, B.; Wall, K.H.; Wates, R.W.

1994-01-01

The principal conclusion from the programme of work carried out by the CEGB was that Carbohydrazide appeared to be the most promising alternative to hydrazine for boiler feedwater conditioning. It is an effective oxygen scavenger at higher feedwater temperatures, its breakdown products are not a serious threat to circuit materials and it is safer to handle than hydrazine. The main disadvantages, at the time of the study, appeared to be the lack of a simple reliable method for measuring residual carbohydrazide in feedwater and a cost for the alternative chemical of up to 20 times that of hydrazine. (orig.)

Chemical reactions in organic monomolecular layers. Condensation of hydrazine on carbonyl functions

International Nuclear Information System (INIS)

Rosilio, Charles; Ruaudel-Teixier, Annie.

1976-01-01

Evidence is given for chemical reactions of hydrazine (NH 2 -NH 2 ) with different carbonyl functional groups of organic molecules in the solid state, in monomolecular layer structures. The condensation of hydrazine with these molecules leads to conjugated systems by bridging the N-N links, to cyclizations, and also to polycondensations. The reactions investigated were followed up by infrared spectrophotometry, by transmission and metallic reflection. These chemical reactions revealed in the solid phase constitute a polycondensation procedure which is valuable in obtaining organized polymers in monomolecular layers [fr

Electrocatalytic oxidation of hydrazine and hydroxylamine by graphene oxide-Pd nanoparticle-modified glassy carbon electrode.

Science.gov (United States)

Lee, Eunhee; Kim, Daekun; You, Jung-Min; Kim, Seul Ki; Yun, Mira; Jeon, Seungwon

2012-12-01

Pd nanoparticle catalysts supported by thiolated graphene oxide (tGO) on a glassy carbon electrode (GCE), and denoted as tGO-Pd/GCE, are used in this study for the electrochemical determination of hydroxylamine and hydrazine. The physicochemical properties of tGO-Pd were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). They showed strong catalytic activity toward the oxidation of hydroxylamine and hydrazine. Cyclic voltammetry (CV) and amperometry were used to characterize the sensors' performances. The detection limits of hydroxylamine and hydrazine by tGO-Pd/GCE were 0.31 and 0.25 microM (s/n = 3), respectively. The sensors' sensitivity, selectivity, and stability were also investigated.

Chemistry and propulsion; Chimie et propulsions

Energy Technology Data Exchange (ETDEWEB)

Potier, P [Maison de la Chimie, 75 - Paris (France); Davenas, A [societe Nationale des Poudres et des Explosifs - SNPE (France); Berman, M [Air Force Office of Scientific Research, Arlington, VA (United States); and others

2002-07-01

During the colloquium on chemistry and propulsion, held in march 2002, ten papers have been presented. The proceedings are brought in this document: ramjet, scram-jet and Pulse Detonation Engine; researches and applications on energetic materials and propulsion; advances in poly-nitrogen chemistry; evolution of space propulsion; environmental and technological stakes of aeronautic propulsion; ramjet engines and pulse detonation engines, automobiles thermal engines for 2015, high temperature fuel cells for the propulsion domain, the hydrogen and the fuel cells in the future transports. (A.L.B.)

Proceedings: Power Plant Electric Auxiliary Systems Workshop

International Nuclear Information System (INIS)

1992-06-01

The EPRI Power Plant Electric Auxiliary Systems Workshop, held April 24--25, 1991, in Princeton, New Jersey, brought together utilities, architect/engineers, and equipment suppliers to discuss common problems with power plant auxiliary systems. Workshop participants presented papers on monitoring, identifying, and solving problems with auxiliary systems. Panel discussions focused on improving systems and existing and future plants. The solutions presented to common auxiliary system problems focused on practical ideas that can enhance plant availability, reduce maintenance costs, and simplify the engineering process. The 13 papers in these proceedings include: Tutorials on auxiliary electrical systems and motors; descriptions of evaluations, software development, and new technologies used recently by electric utilities; an analysis of historical performance losses caused by power plant auxiliary systems; innovative design concepts for improving auxiliary system performance in future power plants

X-ray absorption spectroscopy study on the thermal and hydrazine reduction of graphene oxide

International Nuclear Information System (INIS)

Liang, Xianqing; Wang, Yu; Zheng, Huiyuan; Wu, Ziyu

2014-01-01

Highlights: • XAS study of GO and reduced GO was performed. • Detailed evolution of the electronic structures and chemical bonding of GO was revealed. • A new efficient route for the reduction of GO is proposed. - Abstract: X-ray absorption spectroscopy (XAS) was applied to systemically investigate the deoxygenation of graphene oxide (GO) via annealing and hydrazine treatment. Detailed evolution of the electronic structures and chemical bonding of GO was presented. The enhanced intensity of π * resonance and the appearance of splitting σ * resonance in C K-edge XAS spectra suggest high extents of recoveries of π-conjugation upon reduction using thermal annealing or hydrazine. Experimental results revealed that the carboxyl as well as epoxide and hydroxyl groups on the surface of GO were thermally reduced first, followed by the more difficult removal of carbonyl and cyclic ether groups at higher temperatures. The hydrazine reduction could remove epoxide, hydroxyl and carboxyl groups effectively, whereas the carbonyl groups were partially reduced with the incorporation of nitrogen species simultaneously. The residual oxygen functional groups on hydrazine-reduced GO could be further removed after modest thermal annealing. It was proposed that a combination of both types of reductions would give the best deoxygenation efficiency for the production of graphene

Auxiliary Deep Generative Models

DEFF Research Database (Denmark)

Maaløe, Lars; Sønderby, Casper Kaae; Sønderby, Søren Kaae

2016-01-01

Deep generative models parameterized by neural networks have recently achieved state-of-the-art performance in unsupervised and semi-supervised learning. We extend deep generative models with auxiliary variables which improves the variational approximation. The auxiliary variables leave...... the generative model unchanged but make the variational distribution more expressive. Inspired by the structure of the auxiliary variable we also propose a model with two stochastic layers and skip connections. Our findings suggest that more expressive and properly specified deep generative models converge...... faster with better results. We show state-of-the-art performance within semi-supervised learning on MNIST (0.96%), SVHN (16.61%) and NORB (9.40%) datasets....

30 CFR 57.6161 - Auxiliary facilities.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Auxiliary facilities. 57.6161 Section 57.6161...-Underground Only § 57.6161 Auxiliary facilities. (a) Auxiliary facilities used to store explosive material near work places shall be wooden, box-type containers equipped with covers or doors, or facilities...

45 CFR 707.10 - Auxiliary aids.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false Auxiliary aids. 707.10 Section 707.10 Public Welfare Regulations Relating to Public Welfare (Continued) COMMISSION ON CIVIL RIGHTS ENFORCEMENT OF... § 707.10 Auxiliary aids. (a) The Agency shall furnish appropriate auxiliary aids where necessary to...

Sea trials of wave propulsion of a yacht using a flexible fin propeller

Energy Technology Data Exchange (ETDEWEB)

McGregor, R.C.; Thomson, G.R. [Glasgow Univ. (United Kingdom). Dept. of Mechanical Engineering

1997-02-01

Evidence has been accumulating from theoretical and model test studies over several years that propellers that could be designated as ``oscillating foil`` are potentially more energy efficient than conventional screw propellers. There has been demonstrations that, in the controlled conditions of a laboratory, the flexible fin propeller can convert wave energy into an auxiliary means of forward propulsion. Two questions which are immediately raised are ``is the effect realisable in a real seaway?`` and ``what is the mechanism of energy transfer?``. This paper provides clear evidence of a positive answer to the first question. (author)

An Improved Calibration Method for Hydrazine Monitors for the United States Air Force

Energy Technology Data Exchange (ETDEWEB)

Korsah, K

2003-07-07

This report documents the results of Phase 1 of the ''Air Force Hydrazine Detector Characterization and Calibration Project''. A method for calibrating model MDA 7100 hydrazine detectors in the United States Air Force (AF) inventory has been developed. The calibration system consists of a Kintek 491 reference gas generation system, a humidifier/mixer system which combines the dry reference hydrazine gas with humidified diluent or carrier gas to generate the required humidified reference for calibrations, and a gas sampling interface. The Kintek reference gas generation system itself is periodically calibrated using an ORNL-constructed coulometric titration system to verify the hydrazine concentration of the sample atmosphere in the interface module. The Kintek reference gas is then used to calibrate the hydrazine monitors. Thus, coulometric titration is only used to periodically assess the performance of the Kintek reference gas generation system, and is not required for hydrazine monitor calibrations. One advantage of using coulometric titration for verifying the concentration of the reference gas is that it is a primary standard (if used for simple solutions), thereby guaranteeing, in principle, that measurements will be traceable to SI units (i.e., to the mole). The effect of humidity of the reference gas was characterized by using the results of concentrations determined by coulometric titration to develop a humidity correction graph for the Kintek 491 reference gas generation system. Using this calibration method, calibration uncertainty has been reduced by 50% compared to the current method used to calibrate hydrazine monitors in the Air Force inventory and calibration time has also been reduced by more than 20%. Significant findings from studies documented in this report are the following: (1) The Kintek 491 reference gas generation system (generator, humidifier and interface module) can be used to calibrate hydrazine detectors. (2) The

and Silver(I) Complexes of Hydrazine-Bridged Diphosphine Ligands

African Journals Online (AJOL)

NICO

Gold(I), silver(I), hydrazine, diphosphine, antitumour, anticancer, mitochondrial membrane potential. 1. Introduction. The use of inorganic compounds as cancer treatment became well established with the FDA approval of cisplatin in 1978.1. Cisplatin, carboplatin and oxaliplatin are widely used in clinical settings today.

A Fluorescent Probe for Sensitive Detection of Hydrazine and Its Application in Red Wine and Water.

Science.gov (United States)

Wang, Jialin; Wang, Hao; Yang, Shaoxiang; Tian, Hongyu; Liu, Yongguo; Hao, Yanfeng; Zhang, Jie; Sun, Baoguo

2018-01-01

A fluorescent probe, 7-(diethylamino)-2-oxo-2H-chromene-4-carbaldehyde (probe 1), was designed and synthesized for the sensitive detection of hydrazine. The addition of N 2 H 4 caused the fluorescence intensity of probe 1 to decrease. The probe's fluorescence was turn-off after adding N 2 H 4 , which could be observed under UV light at 365 nm. Moreover, once treated with different concentrations N 2 H 4 solutions, the solution color change could be distinguished, which indicates that probe 1 could be used as a visual sensor for hydrazine. Moreover, probe 1 can be used as a signal tool to determine hydrazine levels in solutions, such as red wine and water.

Gas chromatographic determination of residual hydrazine and morpholine in boiler feed water and steam condensates

International Nuclear Information System (INIS)

Vatsala, S.; Bansal, V.; Tuli, D.K.; Rai, M.M.; Jain, S.K.; Srivastava, S.P.; Bhatnagar, A.K.

1994-01-01

Hydrazine, an oxygen scavenger in boiler water, was derivatised to the corresponding acetone azine and determined at the ng ml -1 level by gas chromatography. Morpholine, a corrosion inhibitor used in steam boilers, was estimated either directly (if >2.0 μg ml -1 ) or by quantitative preconcentration (0.1 ng-2.0 μg ml -1 ). To obtain symmetrical peaks for these amines, the column packing was coated with KOH. Use of a nitrogen-specific detector improved accuracy of estimation of hydrazine and morpholine, giving a RSD of 1.9-3.6%. Chromatographic analysis of these amines in boiler feed water and steam condensate samples collected from boilers servicing a pertroleum refinery is described. Environmental safety regulations calls for monitoring of hydrazine and the methods developed can easily be adapted for this purpose. (orig.)

Investigation of the direct and indirect electrochemical oxidation of hydrazine in nitric acid medium on platinum

International Nuclear Information System (INIS)

Cames, B.

1997-01-01

In nuclear fuel processing by the PUREX process, the purification of plutonium in nitric acid medium requires the oxidation of Pu(III) to Pu(IV), and of hydrazinium nitrate to nitrogen. The study helped to characterize the electrochemical behavior of the oxidation of hydrazinium nitrate and the reduction of nitric acid to nitrous acid, a compound which can chemically oxidize hydrazinium nitrate and Pu(III). Electro-analytical studies on polycrystalline platinum showed that hydrazine is oxidized in two potential zones, which depend on the surface texture of the platinum anode. Electrolysis in separate compartments, carried out in medium-acid media (2 and 4 mo/l) in the potential zone where these processes take place, showed that, at 0.9 V/ECS, the hydrazine oxidation reactions involved are: a four-electron process (75 %) with nitrogen formation and a one-electron process (25 %) with formation of nitrogen and ammonium ion. By contrast, electrolysis carried out at 0.65 V/ECS (with reactivation of the electrode at - 0.2 V/ECS to remove the poison from the platinum) allowed the selective oxidation of hydrazine to nitrogen by the four-electron reaction. Nitric acid can only be reduced to nitrous acid in the absence of hydrazine. For medium-acid media (≤ 6 mol/l), this reaction takes place at potentials below - 0.2 V/ECS. However, the production rate of nitrous acid (partial order 0 with respect to nitric acid) is very low compared with the values obtained for strongly-acid media (6 to 10 mol/l) at the potential of - 0.1 V/ECS. Note that, in concentrated nitric medium, the selectivity of the reduction reaction is 47 to 85 % for nitrous acid, depending on the nitric acid concentration (6 to 10 mol/l) and the potential imposed (- 0.1 ≤ E ≤ 0.6 V/ECS). A kinetic study helped to determine the hydrazine oxidation rates as a function of the operating conditions. In all cases, the reaction rate is of partial order 0 with respect to hydrazine. These studies accordingly

Auxiliary mine ventilation manual

International Nuclear Information System (INIS)

Workplace Safety North

2010-01-01

An adequate ventilation system is needed for air quality and handling in a mine and is comprised of many different pieces of equipment for removing contaminated air and supplying fresh air and thereby provide a satisfactory working environment. This manual highlights auxiliary ventilation systems made up of small fans, ducts, tubes, air movers, deflectors and additional air flow controls which distribute fresh air delivered by the primary system to all areas. A review of auxiliary ventilation is provided. Design, operation and management issues are discussed and guidelines are furnished. This manual is limited to underground hard rock operations and does not address directly other, specific auxiliary systems, either in underground coal mines or uranium mines.

Auxiliary mine ventilation manual

Energy Technology Data Exchange (ETDEWEB)

Workplace Safety North

2010-07-01

An adequate ventilation system is needed for air quality and handling in a mine and is comprised of many different pieces of equipment for removing contaminated air and supplying fresh air and thereby provide a satisfactory working environment. This manual highlights auxiliary ventilation systems made up of small fans, ducts, tubes, air movers, deflectors and additional air flow controls which distribute fresh air delivered by the primary system to all areas. A review of auxiliary ventilation is provided. Design, operation and management issues are discussed and guidelines are furnished. This manual is limited to underground hard rock operations and does not address directly other, specific auxiliary systems, either in underground coal mines or uranium mines.

Mechanical (turbines and auxiliary equipment)

CERN Document Server

Sherry, A; Cruddace, AE

2013-01-01

Modern Power Station Practice, Volume 3: Mechanical (Turbines and Auxiliary Equipment) focuses on the development of turbines and auxiliary equipment used in power stations in Great Britain. Topics covered include thermodynamics and steam turbine theory; turbine auxiliary systems such as lubrication systems, feed water heating systems, and the condenser and cooling water plants. Miscellaneous station services, and pipework in power plants are also described. This book is comprised of five chapters and begins with an overview of thermodynamics and steam turbine theory, paying particular attenti

Hydrazine and hydroxylamine as probes for O2-reduction site of mitochondrial cytochrome c oxidase.

Science.gov (United States)

Kubota, T; Yoshikawa, S

1993-01-01

Reactions of hydrazine and hydroxylamine with bovine heart cytochrome c oxidase in the fully reduced state were investigated under anaerobic conditions following the visible-Soret spectral change. Hydrazine gave a sharp band at 575 nm with 20% decrease in the alpha band at 603 nm, and hydroxylamine induced a 2 nm blue-shift for the alpha band without any clear splitting. The Soret band at 443 nm was decreased significantly in intensity, with the concomitant appearance of a shoulder with hydrazine or a peak with hydroxylamine, both near 430 nm. The dependence on pH of the affinity of these reagents for the enzyme indicates that only the deprotonated forms of these reagents bind to the enzyme, suggesting a highly hydrophobic environment of the haem ligand-biding site. These spectral changes were largely removed by addition of cyanide or CO. However, detailed analysis of these spectral changes indicates that hydrazine perturbs the shape of the spectral change induced by cyanide and hydroxylamine perturbs that induced by CO. These results suggest that these aldehyde reagents bind to haem a3 iron as well as to a second site which is most likely to be the formyl group on the haem periphery, and that these two sites bind these reagents anti-cooperatively with each other. PMID:8389138

Hydrazine-induced thermo-reversible optical shifts in silver-gelatin bionanocomposites

Science.gov (United States)

Aimé, Carole; Rietveld, Ivo B.; Coradin, Thibaud

2011-03-01

Bionanocomposites formed by in situ growth of silver nanoparticles within gelatin gels exhibit large (up to 100 nm) thermo-reversible optical shifts resulting from the enhancement of gel matrix scattering by the interaction of the biopolymer with the hydrazine reducing agent.

hydrazines and their nickel(II) complexes: Syntheses, structures and ...

Indian Academy of Sciences (India)

G Narendra Babu

Abstract. The Schiff bases N-(acyl)-N -(ferrocenylidene)hydrazines (HFcah (1) and HFcbh (2), where acyl = acetyl in 1 and benzoyl in 2 and H represents the dissociable amide proton) were synthesized in high yields (74 and 81%) by condensation reactions of equimolar amounts of ferrocene-carboxaldehyde and the ...

Proceedings of the Conference on the Environmental Chemistry of Hydrazine Fuels (3rd) Held in Panama City Beach, Florida on 15-17 September 1987

Science.gov (United States)

1988-01-01

aqueous or alcoholic hydrazine. It is interesting to note that no chromium (II) hydrazine complex has been prepared directly from a chromium (III...S.E. Bowden, " Oxydation of Hydrazine in Aqueous Solutions", CEEDO-TR-78-11 (1978). AD-A058239. N72-12242. 117p VIBRATIONAL SPECTROSCOPIC STUDY OF THE...phthalocyanlne. Stearyl alcohol was added to improve the transfer, The response to hydrazine was fast, but the sensors were very slow to recover.(3) The

Auxiliary reactor for a hydrocarbon reforming system

Science.gov (United States)

Clawson, Lawrence G.; Dorson, Matthew H.; Mitchell, William L.; Nowicki, Brian J.; Bentley, Jeffrey M.; Davis, Robert; Rumsey, Jennifer W.

2006-01-17

An auxiliary reactor for use with a reformer reactor having at least one reaction zone, and including a burner for burning fuel and creating a heated auxiliary reactor gas stream, and heat exchanger for transferring heat from auxiliary reactor gas stream and heat transfer medium, preferably two-phase water, to reformer reaction zone. Auxiliary reactor may include first cylindrical wall defining a chamber for burning fuel and creating a heated auxiliary reactor gas stream, the chamber having an inlet end, an outlet end, a second cylindrical wall surrounding first wall and a second annular chamber there between. The reactor being configured so heated auxiliary reactor gas flows out the outlet end and into and through second annular chamber and conduit which is disposed in second annular chamber, the conduit adapted to carry heat transfer medium and being connectable to reformer reaction zone for additional heat exchange.

30 CFR 75.331 - Auxiliary fans and tubing.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Auxiliary fans and tubing. 75.331 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.331 Auxiliary fans and tubing. (a) When auxiliary fans and tubing are used for face ventilation, each auxiliary fan shall be— (1...

2-(Hetero(aryl)methylene)hydrazine-1-carbothioamides as potent urease inhibitors.

Science.gov (United States)

Saeed, Aamer; Imran, Aqeel; Channar, Pervaiz A; Shahid, Mohammad; Mahmood, Wajahat; Iqbal, Jamshed

2015-02-01

A small series of 2-(hetero(aryl)methylene) hydrazine-1-carbothioamides including two aryl derivatives was synthesized and tested for their inhibitory activity against urease. Compound (E)-2-(Furan-2-ylmethylene) hydrazine-1-carbothioamide (3f), having a furan ring, was the most potent inhibitor of urease with an IC50 value of 0.58 μM. Molecular modeling was carried out through docking the designed compounds into the urease binding site to predict whether these derivatives have analogous binding mode to the urease inhibitors. The study revealed that all of the tested compounds bind with both metal atoms at the active site of the enzyme. The aromatic ring of the compounds forms ionic interactions with the residues, Ala(440), Asp(494), Ala(636), and Met(637). © 2014 John Wiley & Sons A/S.

The influence of tertiary butyl hydrazine as a co-reactant on the atomic layer deposition of silver

Energy Technology Data Exchange (ETDEWEB)

Golrokhi, Zahra; Marshall, Paul A.; Romani, Simon [Centre for Materials and Structures, School of Engineering,The University of Liverpool, Liverpool L69 3GH (United Kingdom); Rushworth, Simon [EpiValence, The Wilton Centre, Redcar, Cleveland, TS10 4RF (United Kingdom); Chalker, Paul R. [Centre for Materials and Structures, School of Engineering,The University of Liverpool, Liverpool L69 3GH (United Kingdom); Potter, Richard J., E-mail: rjpott@liverpool.ac.uk [Centre for Materials and Structures, School of Engineering,The University of Liverpool, Liverpool L69 3GH (United Kingdom)

2017-03-31

Highlights: • We demonstrate metallic silver growth by direct liquid injection thermal ALD. • A substituted hydrazine is used as a powerful reducing agent for the first time. • The hydrazine extends the ALD temperature window compared with alcohol. • Hydrazine promotes a more planar growth mode compared to alcohol. • Film adhesion is improved using hydrazine compared with alcohol. - Abstract: Ultra-thin conformal silver films are the focus of development for applications such as anti-microbial surfaces, optical components and electronic devices. In this study, metallic silver films have been deposited using direct liquid injection thermal atomic layer deposition (ALD) using (hfac)Ag(1,5-COD) ((hexafluoroacetylacetonato)silver(I)(1,5-cyclooctadiene)) as the metal source and tertiary butyl hydrazine (TBH) as a co-reactant. The process provides a 23 °C wide ‘self-limiting’ ALD temperature window between 105 and 128 °C, which is significantly wider than is achievable using alcohol as a co-reactant. A mass deposition rate of ∼20 ng/cm{sup 2}/cycle (∼0.18 Å/cycle) is observed under self-limiting growth conditions. The resulting films are crystalline metallic silver with a near planar film-like morphology which are electrically conductive. By extending the temperature range of the ALD window by the use of TBH as a co-reactant, it is envisaged that the process will be exploitable in a range of new low temperature applications.

Alkalization of steam and condensate with 2-amino-1-butanol and hydrazine; Alkalisering av aanga och kondensat med butanolamin och hydrazin

Energy Technology Data Exchange (ETDEWEB)

Falk, I [Studsvik Material AB, Nykoeping (Sweden)

1996-04-01

To maintain a low corrosion level in steam- and condensate systems at power and industrial plants, an alkalization of the steam is needed. A low corrosion level lowers the risk of operation disturbances and reduces the cost of the condensate clean up. A better knowledge in the behavior of the alkalis will improve the possibilities to avoid the corrosion attacks. In this work experimental measurements have been carried out during steam boiler conditions as temperature, continuous steam generation and condensation. It has been found that the volatility of 2-amino-1-butanol is very low during stationary dynamic conditions at 250 deg C and 120 deg C. To achieve a high ph-value in the final condensate a very high concentration of 2-amino-1-butanol is thus needed especially when the steam contains acidic compounds. The alkalization effect is obtained from ammonia which is created by thermal decomposition of hydrazine in the boiler water. It is necessary to carry out experimental investigations showing the thermal stability of organic compounds in boiler water before it is possible to recommend them as better volatile alkalis than ammonia and hydrazine. 6 refs, 13 figs

The development of a non-cryogenic nitrogen/oxygen supply system. [using hydrazine/water electrolysis

Science.gov (United States)

Greenough, B. M.; Mahan, R. E.

1974-01-01

A hydrazine/water electrolysis process system module design was fabricated and tested to demonstrate component and module performance. This module is capable of providing both the metabolic oxygen for crew needs and the oxygen and nitrogen for spacecraft leak makeup. The component designs evolved through previous R and D efforts, and were fabricated and tested individually and then were assembled into a complete module which was successfully tested for 1000 hours to demonstrate integration of the individual components. A survey was made of hydrazine sensor technology and a cell math model was derived.

46 CFR 63.25-1 - Small automatic auxiliary boilers.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Small automatic auxiliary boilers. 63.25-1 Section 63.25... AUXILIARY BOILERS Requirements for Specific Types of Automatic Auxiliary Boilers § 63.25-1 Small automatic auxiliary boilers. Small automatic auxiliary boilers defined as having heat-input ratings of 400,000 Btu/hr...

7 CFR 15b.37 - Auxiliary aids.

Science.gov (United States)

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Auxiliary aids. 15b.37 Section 15b.37 Agriculture... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Other Aid, Benefits, or Services § 15b.37 Auxiliary aids... appropriate auxiliary aids to persons with impaired sensory, manual, or speaking skills, where necessary to...

30 CFR 57.8529 - Auxiliary fan systems

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Auxiliary fan systems 57.8529 Section 57.8529 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Underground Only § 57.8529 Auxiliary fan systems When auxiliary fan systems are used, such systems shall...

Ammonia and hydrazine. Transition-metal-catalyzed hydroamination and metal-free catalyzed functionalization

Energy Technology Data Exchange (ETDEWEB)

Bertrand, Guy [Univ. of California, San Diego, CA (United States)

2012-06-29

The efficient and selective preparation of organic molecules is critical for mankind. For the future, it is of paramount importance to find catalysts able to transform abundant and cheap feedstocks into useful compounds. Acyclic and heterocyclic nitrogen-containing derivatives are common components of naturally occurring compounds, agrochemicals, cosmetics, and pharmaceuticals; they are also useful intermediates in a number of industrial processes. One of the most widely used synthetic strategies, allowing the formation of an N-C bond, is the addition of an N-H bond across a carbon-carbon multiple bond, the so-called hydroamination reaction. This chemical transformation fulfills the principle of “green chemistry” since it ideally occurs with 100% atom economy. Various catalysts have been found to promote this reaction, although many limitations remain; one of the most prominent is the lack of methods that permit the use of NH₃ and NH₂NH₂ as the amine partners. In fact, ammonia and hydrazine have rarely succumbed to homogeneous catalytic transformations. Considering the low cost and abundance of ammonia (136 million metric tons produced in 2011) and hydrazine, catalysts able to improve the reactivity and selectivity of the NH₃- and NH₂NH₂-hydroamination reaction, and more broadly speaking the functionalization of these chemicals, are highly desirable. In the last funded period, we discovered the first homogeneous catalysts able to promote the hydroamination of alkynes and allenes with ammonia and the parent hydrazine. The key feature of our catalytic systems is that the formation of catalytically inactive Werner complexes is reversible, in marked contrast to most of the known ammonia and hydrazine transition metal complexes. This is due to the peculiar electronic properties of our neutral ancillary ligands, especially their strong donating capabilities. However, our catalysts currently require

Preparation of three-dimensional porous Cu film supported on Cu foam and its electrocatalytic performance for hydrazine electrooxidation in alkaline medium

International Nuclear Information System (INIS)

Liu, Ran; Ye, Ke; Gao, Yinyi; Long, Ziyao; Cheng, Kui; Zhang, Wenping; Wang, Guiling; Cao, Dianxue

2016-01-01

Highlights: • A binder-free Cu/Cu foam electrode is prepared by an electrochemical method. • The electrode owns a novel three-dimensional porous structure. • The electrode exhibits superior catalytic activity for hydrazine electrooxidation. - Abstract: A three-dimensional porous copper film is directly deposited on Cu foam by an electrodeposition method using hydrogen bubbles as dynamic template (denoted as Cu/Cu foam). Its electrocatalytic activity toward hydrazine electrooxidation is tested by linear sweep voltammetry, chronoamperometry and electrochemical impedance spectroscopy. Compared with Cu foam, hydrazine electrooxidation on the Cu/Cu foam electrode shows that the onset oxidation potential displays a ~100 mV negative shift, the current density at −0.6 V raises about 14 times, the apparent activation energy and the charge transfer resistance reduce significantly. The increasing electrocatalytic performance for hydrazine electrooxidation is mainly caused by the highly porous structure of the Cu/Cu foam electrode which can provide a large surface area and make electrolyte access the electrocatalyst surfaces more easily. Hydrazine electrooxidation on the Cu/Cu foam electrode proceeds through a near 4-electron process.

Synthesis and Free Radical Scavenging Activity of New Hydroxybenzylidene Hydrazines.

Science.gov (United States)

Sersen, Frantisek; Gregan, Fridrich; Kotora, Peter; Kmetova, Jarmila; Filo, Juraj; Loos, Dusan; Gregan, Juraj

2017-05-29

Hydroxybenzylidene hydrazines exhibit a wide spectrum of biological activities. Here, we report synthesis and free radical scavenging activity of nine new N-(hydroxybenzylidene)-N'-[2,6-dinitro-4-(trifluoromethyl)]phenylhydrazines. The chemical structures of these compounds were confirmed by 1H-NMR, 13C-NMR, 19F-NMR, IR spectroscopy, LC-MS, and elemental analysis. The prepared compounds were tested for their activity to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH), galvinoxyl radical (GOR), and 2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulphonic acid (ABTS) radicals. The free radical scavenging activity expressed as SC50 values of these compounds varied in a wide range, from a strong to no radical scavenging effect. The most effective radical scavengers were hydroxybenzylidene hydrazines containing three hydroxyl groups in the benzylidene part of their molecules. The prepared compounds were also tested for their activity to inhibit photosynthetic electron transport in spinach chloroplasts. IC50 values of these compounds varied in wide range, from an intermediate to no inhibitory effect.

Preparation of 3,5-disubstituted pyrazoles and isoxazoles from terminal alkynes, aldehydes, hydrazines, and hydroxylamine.

Science.gov (United States)

Harigae, Ryo; Moriyama, Katsuhiko; Togo, Hideo

2014-03-07

The reaction of terminal alkynes with n-BuLi, and then with aldehydes, followed by the treatment with molecular iodine, and subsequently hydrazines or hydroxylamine provided the corresponding 3,5-disubstituted pyrazoles or isoxazoles in good yields with high regioselectivity, through the formations of propargyl secondary alkoxides and α-alkynyl ketones. The present reactions are one-pot preparation of 3,5-disubstituted pyrazoles from terminal alkynes, aldehydes, molecular iodine, and hydrazines, and 3,5-disubstituted isoxazoles from terminal alkynes, aldehydes, molecular iodine, and hydroxylamine.

Nanostructured SnO{sub 2} encapsulated guar-gum hybrid nanocomposites for electrocatalytic determination of hydrazine

Energy Technology Data Exchange (ETDEWEB)

Malik, Priya [Department of Applied Chemistry & Polymer Technology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042 (India); Srivastava, Manish [Department of Physics & Astrophysics, University of Delhi, Delhi 110007 (India); Verma, Ranjana [Solar Energy Material Laboratory, Department of Energy, Tezpur University, Tezpur, Assam 784 028 (India); Kumar, Manish [Department of Applied Chemistry & Polymer Technology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042 (India); Kumar, D., E-mail: dkumar@dce.ac.in [Department of Applied Chemistry & Polymer Technology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042 (India); Singh, Jay, E-mail: jay_singh143@yahoo.co.in [Department of Applied Chemistry & Polymer Technology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042 (India)

2016-01-01

The present article deals with synthesis of sol–gel derived tin dioxide (SnO{sub 2}) nanoparticles encapsulated in to guar gum (GG) biopolymer as the organic–inorganic hybrid materials for the determination of hydrazine. The organic–inorganic hybrid combines the perfunctory strength offered by the inorganic SnO{sub 2} nanoparticles with flexible binding sites provided by the organic biopolymer (GG) solution by the ultrasonication. The phase identification, crystalline size, surface morphology and optical properties of prepared SnO{sub 2} and SnO{sub 2}-GG nanocomposites has been investigated through FT-IR, XRD, SEM, AFM, TEM, UV–Vis, and PL techniques. The colloidal solution of SnO{sub 2} and GG is electrophoretically deposited (EPD) onto the indium tin-oxide (ITO) glass substrate and studied for the electrooxidation of hydrazine. Under the optimized experimental conditions, the linearity between the current response and the hydrazine concentration has been obtained in the range of 2–22 mM, with a low detection limit of 2.76 mM and a high sensitivity of 5.72 μA cm{sup −2}. Based on the linear increase in amperometric current, a sensitive hydrazine electrochemical sensor is constructed. The proposed SnO{sub 2}-GG/ITO electrode shows a good response time (35 s), reproducibility, and long-term stability. The obtained results suggest that SnO{sub 2}-GG nanocomposites electrode provides a favorable sensing platform for the electrochemical studies. In addition, the cyclic voltammetry (CV) studies are used to evaluate the kinetic parameters. - Graphical abstract: Synthesis of sol–gel derived tin dioxide (SnO{sub 2}) nanoparticles grafted in to gaur gum (GG) organic–inorganic hybrid nanocomposite for determination of hydrazine (HZ). Under optimized experimental conditions, SnO{sub 2}-GG/ITO electrode shows, linearity 2–22 mM, and detection limit 2.769 mM with high sensitivity of 5.72 μA cm{sup −2}. The results clearly suggest that SnO{sub 2}-GG

33 CFR 5.47 - Auxiliary ensign.

Science.gov (United States)

2010-07-01

... matching blue Coast Guard Auxiliary emblem is centered. The white slash shall be at a 70 degree angle, rising away from the hoist. (c) The Auxiliary emblem consists of a disk with the shield of the Coat of...

Electrochemical behavior of rhodium acetamidate immobilized on a carbon paste electrode: a hydrazine sensor

Directory of Open Access Journals (Sweden)

Gil Eric de S.

2000-01-01

Full Text Available The electrochemical behavior of rhodium acetamidate immobilized in carbon paste electrode and the consequences for sensor construction were evaluated. The electrode showed good stability and redox properties. Two reversible redox couples with midpoint potentials between 0.15 and 0.55 V vs SCE were observed. However, peak resolution in voltammetric studies was very dependent on the supporting electrolyte. The correlation between coordinating power of the electrolyte and peak potential suggests that the electrolyte can coordinate through the axial position of the complexes. Furthermore, the axial position may be also the catalytic site, as a catalytical response was observed for hydrazine oxidation. A good linear response range for hydrazine was fit by the equation i = 23.13 (± 0.34 c , where i = current in mA and c = concentration in mol dm-3 in the range of 10-5 up to 10-2 mol dm-3. The low applied potential (<300 mV indicates a good device for hydrazine sensor, minimizing interference problems. The short response time (~1 s may be useful in flow injection analysis. Furthermore, this system was very stable presenting good repeatability even after 30 measurements with a variance of 0.5 %.

Influence of hydrazine primary water chemistry on corrosion of fuel cladding and primary circuit components

International Nuclear Information System (INIS)

Iourmanov, V.; Pashevich, V.; Bogancs, J.; Tilky, P.; Schunk, J.; Pinter, T.

1999-01-01

Earlier at Paks 1-4 NPP standard ammonia chemistry was in use. The following station performance indicators were improved when hydrazine primary water chemistry was introduced: occupational radiation exposures of personnel; gamma-radiation dose rates near primary system components during refuelling and maintenance outages. The reduction of radiation exposures and radiation fields were achieved without significant expenses. Recent results of experimental studies allowed to explain the mechanism of hydrazine dosing influence on: corrosion rate of structure materials in primary coolant; behaviour of soluble and insoluble corrosion products including long-life corrosion-induced radionuclides in primary system during steady-state and transient operation modes; radiolytic generation of oxidising radiolytic products in core and its corrosion activity in primary system; radiation situation during refuelling and maintenance outages; foreign material degradation and removal (including corrosion active oxidant species) from primary system during abnormal events. Operational experience and experimental data have shown that hydrazine primary water chemistry allows to reduce corrosion wear and thereby makes it possible to extend the life-time of plant components in primary system. (author)

Solvent properties of hydrazine in the preparation of metal chalcogenide bulk materials and films.

Science.gov (United States)

Yuan, Min; Mitzi, David B

2009-08-21

A combination of unique solvent properties of hydrazine enables the direct dissolution of a range of metal chalcogenides at ambient temperature, rendering this an extraordinarily simple and soft synthetic approach to prepare new metal chalcogenide-based materials. The extended metal chalcogenide parent framework is broken up during this process, and the resulting metal chalcogenide building units are re-organized into network structures (from 0D to 3D) based upon their interactions with the hydrazine/hydrazinium moieties. This Perspective will review recent crystal and materials chemistry developments within this family of compounds and will briefly discuss the utility of this approach in metal chalcogenide thin-film deposition.

Selective fluorescent detection of aspartic acid and glutamic acid employing dansyl hydrazine dextran conjugate.

Science.gov (United States)

Nasomphan, Weerachai; Tangboriboonrat, Pramuan; Tanapongpipat, Sutipa; Smanmoo, Srung

2014-01-01

Highly water soluble polymer (DD) was prepared and evaluated for its fluorescence response towards various amino acids. The polymer consists of dansyl hydrazine unit conjugated into dextran template. The conjugation enhances higher water solubility of dansyl hydrazine moiety. Of screened amino acids, DD exhibited selective fluorescence quenching in the presence of aspartic acid (Asp) and glutamic acid (Glu). A plot of fluorescence intensity change of DD against the concentration of corresponding amino acids gave a good linear relationship in the range of 1 × 10(-4) M to 25 × 10(-3) M. This establishes DD as a potential polymeric sensor for selective sensing of Asp and Glu.

Performances and improvement of copper-hydrazine complexation deoxidising resin

International Nuclear Information System (INIS)

Liu Fenfen; Zhang Hao; Sun Haijun; Liu Xiaojie

2012-01-01

Copper-hydrazine complexation deoxidising resin is tested to examine its performances including effluent water quality and capacity of deoxidisation. By the means of changing the resin type and regeneration, the deoxidising capacity of the resin can be improved to 13 times more than before. At the same time, physical performances of the resin are also greatly improved while maintaining its velocity of deoxidisation and effluent quality. (authors)

The Acquisition of Auxiliary Syntax: A Longitudinal Elicitation Study. Part 2: The Modals and Auxiliary DO

Science.gov (United States)

Rowland, Caroline F.; Theakston, Anna L.

2009-01-01

Purpose: The study of auxiliary acquisition is central to work on language development and has attracted theoretical work from both nativist and constructivist approaches. This study is part of a 2-part companion set that represents a unique attempt to trace the development of auxiliary syntax by using a longitudinal elicitation methodology. The…

Synthesis and Free Radical Scavenging Activity of New Hydroxybenzylidene Hydrazines

Directory of Open Access Journals (Sweden)

Frantisek Sersen

2017-05-01

Full Text Available Hydroxybenzylidene hydrazines exhibit a wide spectrum of biological activities. Here, we report synthesis and free radical scavenging activity of nine new N-(hydroxybenzylidene-N′-[2,6-dinitro-4-(trifluoromethyl]phenylhydrazines. The chemical structures of these compounds were confirmed by 1H-NMR, 13C-NMR, 19F-NMR, IR spectroscopy, LC-MS, and elemental analysis. The prepared compounds were tested for their activity to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH, galvinoxyl radical (GOR, and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS radicals. The free radical scavenging activity expressed as SC50 values of these compounds varied in a wide range, from a strong to no radical scavenging effect. The most effective radical scavengers were hydroxybenzylidene hydrazines containing three hydroxyl groups in the benzylidene part of their molecules. The prepared compounds were also tested for their activity to inhibit photosynthetic electron transport in spinach chloroplasts. IC50 values of these compounds varied in wide range, from an intermediate to no inhibitory effect.

Destruction of oxalate by reaction with hydrogen peroxide. [Hydrazine oxalate

Energy Technology Data Exchange (ETDEWEB)

Mailen, J.C.; Tallent, O.K.; Arwood, P.C.

1981-09-01

The destruction of oxalate by oxidation to carbon dioxide using hydrogen peroxide was studied as an alternative method for the disposal of oxalate in connection with the possible use of an aqueous hydrazine oxalate solution as a scrubbing agent for solvent cleanup in processes for the recovery of uranium, plutonium, and thorium by solvent extraction. The rate of oxidation of oxalate by hydrogen peroxide in acid solution at the reflux temperature was adequate for process application; reaction half-times at 100/sup 0/C were less than one hour when the hydrogen peroxide concentration was greater than 0.5 M. The reaction was first order with respect to both the oxalate and hydrogen peroxide concentrations and had an activation energy of 58.7 kJ/g-mol. The rate increased with the hydrogen ion concentration as (H/sup +/)/sup 0/ /sup 3/ but was not significantly affected by the presence of 100 ppM of uranium or copper in solution. In the near-neutral hydrazine oxalate solutions, the reaction of either component with hydrogen peroxide was too slow for process application.

Determination of hydrazine in third loops of China experimental fast reactor by spectrophotometry

International Nuclear Information System (INIS)

Huang Wenjie; Wang Mi; Gao Yaopeng; Xie Chun; Yu Xiaochen

2013-01-01

The method for the determination of hydrazine by Uv-vis spectrophotometer was proposed. The coloration conditions and instrument parameters were also optimized. In HCl, hydrazine formed a yellow azine with para-dimethyl aminobenzaldehyde ((CH 3 ) 2 NC 6 H 4 CHO), and then determined by spectrophotometer. The complex's maximum absorption was exhibited at 458 nm. The coloration effect was excellent in conditions of 1% HCl, 10 mL para-dimethyl aminobenzaldehyde and 10 minutes' developing time. A good liner relationship was obtained in the range of 5∼200 μg/L, and the recovery was (101.1±1.9)%. This method was used in the third loop of China experimental fast reactor with satisfactory results. (authors)

CAREM-25. Auxiliary systems

International Nuclear Information System (INIS)

Acosta, Eduardo; Amaya, Daniel; Carlevaris, Rodolfo; Patrignani, A.; Ramilo, L.; Santecchia, A.; Vindrola, C.

2000-01-01

CAREM is an innovative PWR reactor whose prototype will be of small power generation capacity (100MWt, about 25MWe).CAREM design is based on light water integrated reactor with slightly enriched uranium.In this work, a summary of the functions and most relevant design characteristics of main auxiliary systems associated to the chain of heat removal and physicochemical - radiological treatment of the cooling fluids of the CAREM-25 prototype is presented.Even though these auxiliary systems of the reactor are not safety system, they fulfill functions related with the nuclear safety at different operative modes of the reactor

CAREM-25. Auxiliary systems

International Nuclear Information System (INIS)

Acosta, Eduardo; Amaya, Daniel; Carlevaris, Rodolfo; Patrignani, Alberto; Santecchia, Alberto; Vindrola, Carlos; Ramilo, Lucia B.

2000-01-01

CAREM is an innovative PWR reactor whose prototype will be of small power generation capacity (100 M Wt, about 25 M We). CAREM design is based on light water integrated reactor with slightly enriched uranium. In this work, a summary of the functions and most relevant design characteristics of main auxiliary systems associated to the chain of heat removal and physicochemical - radiological treatment of the cooling fluids of the CAREM-25 prototype is presented. Even though these auxiliary systems of the reactor are not safety system, they fulfill functions related with the nuclear safety at different operative modes of the reactor. (author)

Hydrazine-hydrothermal method to synthesize three-dimensional chalcogenide framework for photocatalytic hydrogen generation

International Nuclear Information System (INIS)

Liu Yi; Kanhere, Pushkar D.; Wong, Chui Ling; Tian Yuefeng; Feng Yuhua; Boey, Freddy; Wu, Tom; Chen Hongyu; White, Tim J.; Chen Zhong; Zhang Qichun

2010-01-01

A novel chalcogenide, [Mn 2 Sb 2 S 5 (N 2 H 4 ) 3 ] (1), has been synthesized by the hydrazine-hydrothermal method. X-ray crystallography study reveals that the new compound 1 crystallizes in space group P1-bar (no. 2) of the triclinic system. The structure features an open neutral three-dimensional framework, where two-dimensional mesh-like inorganic layers are bridged by intra- and inter-layer hydrazine ligands. Both two Mn1 and Mn2 sites adopt distorted octahedral coordination. While two Sb1 and Sb2 sites exhibit two different coordination geometries, the Sb1 site is coordinated with three S atoms to generate a SbS 3 trigonal-pyramidal geometry, and the Sb2 site adopts a SbS 4 trigonal bipyramidal coordination geometry. It has an optical band gap of about ∼2.09 eV, which was deduced from the diffuse reflectance spectrum, and displays photocatalytic behaviors under visible light irradiation. Magnetic susceptibility measurements show compound 1 obeys the Curie-Weiss law in the range of 50-300 K. -- Graphical abstract: A novel chalcogenide, [Mn 2 Sb 2 S 5 (N 2 H 4 ) 3 ] (1), synthesized by hydrazine-hydrothermal method, has a band gap of about ∼2.09 eV and displays photocatalytic behaviors under visible light irradiation. Display Omitted

Homoaromatics as intermediates in the substitution reactions of 1,2,4,5-tetrazines with ammonia and hydrazine

International Nuclear Information System (INIS)

Counotte-Potman, A.D.

1981-01-01

This thesis describes some nucleophilic substitution reactions between the red 1,2,4,5-tetrazines and hydrazine-hydrate or ammonia. Special attention was paid to the occurrence of the Ssub(N) (ANRORC) mechanism in these substitution reactions. This mechanism comprises a sequence of reactions, involving the Addition of a Nucleopile to a heteroaromatic species, followed by a Ring-Opening and Ring Closure reaction to the substitution product. 3-Alkyl(aryl)-1,2,4,5-tetrazines were found to undergo a Chichibabin hydrazination into 6-hydrazino-3-alkyl(aryl)-1,2,4,5-tetrazines on treatment with hydrazine-hydrate. The first step in this reaction sequence was the formation of a homoaromatic sigma-adduct. Subsequently an open-chain intermediate was observed by NMR, on raising the temperature. Finally the hydrazino compound is formed by ring closure. This reaction sequence can be considered as an Ssub(N)(ANRORC) process. With 15 N-labelled hydrazine, only part of the label was found to be built in the 1,2,4,5-tetrazine ring of the 6-hydrazino compounds. This is the first example of a reaction in which both the hydrazino compound with the 15 N-label in the ring and with the 15 N-label in the exocyclic hydrazino group are formed according to the Ssub(N)(ANRORC) mechanism. (Auth.)

The Reduction Reaction of Dissolved Oxygen in Water by Hydrazine over Platinum Catalyst Supported on Activated Carbon Fiber

Energy Technology Data Exchange (ETDEWEB)

Park, K.K.; Moon, J.S. [Korea Electric Power Research Institute, Taejon (Korea)

1999-07-01

The reduction reaction of dissolved oxygen (DO) by hydrazine was investigated on activated carbon fiber (ACF) and Pt/ACF catalysts using a batch reactor with an external circulating loop. The ACF itself showed catalytic activity and this was further improved by supporting platinum on ACF. The catalytic role platinum is ascribed to its acceleration of hydrazine decomposition, based on electric potential and current measurements as well as the kinetic study. (author). 15 refs., 13 figs.

Computation within the auxiliary field approach

International Nuclear Information System (INIS)

Baeurle, S.A.

2003-01-01

Recently, the classical auxiliary field methodology has been developed as a new simulation technique for performing calculations within the framework of classical statistical mechanics. Since the approach suffers from a sign problem, a judicious choice of the sampling algorithm, allowing a fast statistical convergence and an efficient generation of field configurations, is of fundamental importance for a successful simulation. In this paper we focus on the computational aspects of this simulation methodology. We introduce two different types of algorithms, the single-move auxiliary field Metropolis Monte Carlo algorithm and two new classes of force-based algorithms, which enable multiple-move propagation. In addition, to further optimize the sampling, we describe a preconditioning scheme, which permits to treat each field degree of freedom individually with regard to the evolution through the auxiliary field configuration space. Finally, we demonstrate the validity and assess the competitiveness of these algorithms on a representative practical example. We believe that they may also provide an interesting possibility for enhancing the computational efficiency of other auxiliary field methodologies

Bayesian Analysis of Geostatistical Models With an Auxiliary Lattice

KAUST Repository

Park, Jincheol; Liang, Faming

2012-01-01

of observations is large. In this article, we propose an auxiliary lattice-based approach for tackling this difficulty. By introducing an auxiliary lattice to the space of observations and defining a Gaussian Markov random field on the auxiliary lattice, our model

Amperometric detection of hydrazine utilizing synergistic action of prussian blue @ silver nanoparticles / graphite felt modified electrode

International Nuclear Information System (INIS)

Zhao, Jihua; Liu, Jianxin; Tricard, Simon; Wang, Lei; Liang, Yanling; Cao, Linghua; Fang, Jian; Shen, Weiguo

2015-01-01

Highlights: • Prussian Blue (PB) deposition on Ag/GF for electrochemical hydrazine sensing; • Lower detection limit of 4.9 × 10 −7 mol L −1 , stable over 24 days; • High sensitivity: 26.06 A mol −1 L. -- Abstract: In this study, a triple-component hydrazine sensor (PB@Ag/GF) was fabricated with freestanding graphite felt (GF), silver nanoparticles (Ag) and prussian blue (PB). The Ag nanoparticles were electrodeposited on GF ultrasonically (Ag/GF), and acted as a catalyst of the chemical deposition of PB. The electrode was characterized by scanning election microscopy (SEM), infrared spectroscopy (IR), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). The electrochemical behavior of PB@Ag/GF was measured by cyclic voltammetry and amperometric measurements. The sensor displayed a prominent electrocatalytic activity toward hydrazine oxidation, with a fast response time of 2 s, a low detection limit of 4.9 × 10 −7 mol L −1 and very high detection sensitivity of 26.06 A mol −1 L

Simultaneous quantitation of hydrazine and acetylhydrazine in human plasma by high performance liquid chromatography-tandem mass spectrometry after derivatization with p-tolualdehyde.

Science.gov (United States)

Song, Lu; Gao, Dan; Li, Shangfu; Wang, Yanwei; Liu, Hongxia; Jiang, Yuyang

2017-09-15

A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for simultaneous quantitative analysis of hydrazine and acetylhydrazine in human plasma based on the strategy of p-tolualdehyde derivatization. The derivatization reactions were easily realized by ultrasonic manipulation for 40min. Good separation of the derivatization products was achieved using a C 18 column by gradient elution. The optimized mass transition ion-pairs (m/z) monitored for the two hydrazine derivatives were m/z 237.1≫>119.9 and m/z 176.9≫>117.8, respectively. The limit of detection (LOD) and limit of quantification (LOQ) for hydrazine were 0.002 and 0.005ngmL -1 separately. And they were 0.03 and 0.05ngmL -1 for acetylhydrazine, respectively. The linear range was 0.005-50ngmL -1 for hydrazine and 0.05-500ngmL -1 for acetylhydrazine with R 2 greater than 0.999. The recovery range was determined to be 95.38-108.12% with the relative standard deviation (RSD) in the range of 1.24-14.89%. The method was successfully applied to detect 30 clinical plasma samples of pulmonary tuberculosis patients treated with isoniazid. The concentrations were from 0.04-1.99ngmL -1 for hydrazine and 0.06-142.43ngmL -1 for acetylhydrazine. The results indicated that our developed method had the potential for the detection of hydrazine toxicology in complex biological samples. Furthermore, the method has an important significance to clinical treatment with drugs. Copyright © 2017. Published by Elsevier B.V.

47 CFR 73.1675 - Auxiliary antennas.

Science.gov (United States)

2010-10-01

... Class A TV licensees may request a decrease from the authorized facility's ERP in the license application. An FM, TV or Class A TV licensee may also increase the ERP of the auxiliary facility in a license... licensed main facility as an auxiliary facility with an ERP less than or equal to the ERP specified on the...

46 CFR 58.25-10 - Main and auxiliary steering gear.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Main and auxiliary steering gear. 58.25-10 Section 58.25... AUXILIARY MACHINERY AND RELATED SYSTEMS Steering Gear § 58.25-10 Main and auxiliary steering gear. (a) Power-operated main and auxiliary steering gear must be separate systems that are independent throughout their...

Sea water take-up facility for cooling reactor auxiliary

International Nuclear Information System (INIS)

Numata, Noriko; Mizutani, Akira; Hirako, Shizuka; Uchiyama, Yuichi; Oda, Atsushi.

1997-01-01

The present invention provides an improvement of a cooling sea water take-up facility for cooling auxiliary equipments of nuclear power plant. Namely, an existent sea water take-up facility for cooling reactor auxiliary equipments has at least two circulation water systems and three independent sea water systems for cooling reactor auxiliary equipments. In this case, a communication water channel is disposed, which connects the three independent sea water systems for cooling reactor auxiliary equipments mutually by an opening/closing operation of a flow channel partitioning device. With such a constitution, even when any combination of two systems among the three circulation water systems is in inspection at the same time, one system for cooling the reactor auxiliary equipments can be kept operated, and one system is kept in a stand-by state by the communication water channel upon periodical inspection of water take-up facility for cooling the auxiliary equipments. As a result, the sea water take-up facility for cooling auxiliary equipments of the present invention have operation efficiency higher than that of a conventional case while keeping the function and safety at the same level as in the conventional case. (I.S.)

14 CFR 29.757 - Hull and auxiliary float strength.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and auxiliary float strength. 29.757... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand the...

Propulsion Systems Panel deliberations

Science.gov (United States)

Bianca, Carmelo J.; Miner, Robert; Johnston, Lawrence M.; Bruce, R.; Dennies, Daniel P.; Dickenson, W.; Dreshfield, Robert; Karakulko, Walt; Mcgaw, Mike; Munafo, Paul M.

1993-01-01

The Propulsion Systems Panel was established because of the specialized nature of many of the materials and structures technology issues related to propulsion systems. This panel was co-chaired by Carmelo Bianca, MSFC, and Bob Miner, LeRC. Because of the diverse range of missions anticipated for the Space Transportation program, three distinct propulsion system types were identified in the workshop planning process: liquid propulsion systems, solid propulsion systems and nuclear electric/nuclear thermal propulsion systems.

Process for treating waste water containing hydrazine from power stations

International Nuclear Information System (INIS)

Hoffmann, W.

1982-01-01

A process for treating waste water containing hydrazine from nuclear power stations is proposed, characterized by the fact that the water is taken continuously through a water decomposition cell. If the water does not have sufficient conductivity itself, a substance raising the electrical conductivity is added to the water to be treated. The electrolysis is situated in the waste water tank. (orig./RB) [de

A QSAR/QSTR Study on the Environmental Health Impact by the Rocket Fuel 1,1-Dimethyl Hydrazine and its Transformation Products

Directory of Open Access Journals (Sweden)

Lars Carlsen

2008-01-01

Full Text Available QSAR/QSTR modelling constitutes an attractive approach to preliminary assessment of the impact on environmental health by a primary pollutant and the suite of transformation products that may be persistent in and toxic to the environment. The present paper studies the impact on environmental health by residuals of the rocket fuel 1,1-dimethyl hydrazine (heptyl and its transformation products. The transformation products, comprising a variety of nitrogen containing compounds are suggested all to possess a significant migration potential. In all cases the compounds were found being rapidly biodegradable. However, unexpected low microbial activity may cause significant changes. None of the studied compounds appear to be bioaccumulating. Apart from substances with an intact hydrazine structure or hydrazone structure the transformation products in general display rather low environmental toxicities. Thus, it is concluded that apparently further attention should be given to tri- and tetramethyl hydrazine and 1-formyl 2,2-dimethyl hydrazine as well as to the hydrazones of formaldehyde and acetaldehyde as these five compounds may contribute to the overall environmental toxicity of residual rocket fuel and its transformation products.

78 FR 27321 - Revision of Auxiliary Regulations

Science.gov (United States)

2013-05-10

... Auxiliary organizational structure, extending civil liability protection to Auxiliary units and members, and... entities. C. Assistance for Small Entities If you think that your business, organization, or governmental..., explain why you think your business or organization qualifies, how and to what degree this rule would...

Automated analysis for nitrate by hydrazine reduction

Energy Technology Data Exchange (ETDEWEB)

Kamphake, L J; Hannah, S A; Cohen, J M

1967-01-01

An automated procedure for the simultaneous determinations of nitrate and nitrite in water is presented. Nitrite initially present in the sample is determined by a conventional diazotization-coupling reaction. Nitrate in another portion of sample is quantitatively reduced with hydrazine sulfate to nitrite which is then determined by the same diazotization-coupling reaction. Subtracting the nitrite initially present in the sample from that after reduction yields nitrite equivalent to nitrate initially in the sample. The rate of analysis is 20 samples/hr. Applicable range of the described method is 0.05-10 mg/l nitrite or nitrate nitrogen; however, increased sensitivity can be obtained by suitable modifications.

Advanced APS Impacts on Vehicle Payloads

Science.gov (United States)

Schneider, Steven J.; Reed, Brian D.

1989-01-01

Advanced auxiliary propulsion system (APS) technology has the potential to both, increase the payload capability of earth-to-orbit (ETO) vehicles by reducing APS propellant mass, and simplify ground operations and logistics by reducing the number of fluids on the vehicle and eliminating toxic, corrosive propellants. The impact of integrated cryogenic APS on vehicle payloads is addressed. In this system, launch propulsion system residuals are scavenged from integral launch propulsion tanks for use in the APS. Sufficient propellant is preloaded into the APS to return to earth with margin and noncomplete scavenging assumed. No propellant conditioning is required by the APS, but ambient heat soak is accommodated. High temperature rocket materials enable the use of the unconditioned hydrogen/oxygen in the APS and are estimated to give APS rockets specific impulse of up to about 444 sec. The payload benefits are quantified and compared with an uprated monomethyl hydrazine/nitrogen tetroxide system in a conservative fashion, by assuming a 25.5 percent weight growth for the hydrogen/oxygen system and a 0 percent weight growth for the uprated system. The combination and scavenging and high performance gives payload impacts which are highly mission specific. A payload benefit of 861 kg (1898 lbm) was estimated for a Space Station Freedom rendezvous mission and 2099 kg (4626 lbm) for a sortie mission, with payload impacts varying with the amount of launch propulsion residual propellants. Missions without liquid propellant scavenging were estimated to have payload penalties, however, operational benefits were still possible.

Propulsion Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The Propulsion Lab simulates field test conditions in a controlled environment, using standardized or customized test procedures. The Propulsion Lab's 11 cells can...

Resolution of concerns in auxiliary feedwater piping

International Nuclear Information System (INIS)

Bain, R.A.; Testa, M.F.

1994-01-01

Auxiliary feedwater piping systems at pressurized water reactor (PWR) nuclear power plants have experienced unanticipated operating conditions during plant operation. These unanticipated conditions have included plant events involving backleakage through check valves, temperatures in portions of the auxiliary feedwater piping system that exceed design conditions, and the occurrence of unanticipated severe fluid transients. The impact of these events has had an adverse effect at some nuclear stations on plant operation, installed plant components and hardware, and design basis calculations. Beaver Valley Unit 2, a three loop pressurized water reactor nuclear plant, has observed anomalies with the auxiliary feedwater system since the unit went operational in 1987. The consequences of these anomalies and plant events have been addressed and resolved for Beaver Valley Unit 2 by performing engineering and construction activities. These activities included pipe stress, pipe support and pipe rupture analysis, the monitoring of auxiliary feedwater system temperature and pressure, and the modification to plant piping, supports, valves, structures and operating procedures

Vacuum switchgear for power station auxiliary switchboards

International Nuclear Information System (INIS)

Coombs, P.E.

1992-01-01

Sizewell B is the first UK power station in which vacuum switchgear is used for the auxiliary switchboards. Previously the 3.3kV, 6.6kV or 11kV switchgear has used air-break circuit breakers and fused air-break contactors, known as motor starting devices or fused switching devices (FSD). The use of vacuum interrupters is therefore a new technology in this application, although it has been established in the UK distribution network and in industrial installations from the mid 1970s. Vacuum switchgear was already in use in the USA for power station auxiliary switchgear at the time that it was proposed for Sizewell B. The Sizewell B high voltage auxiliary switchgear comprises eight Unit and Station Auxiliary Switchboards at 3.3kV and 11kV, and four 3.3kV Essential Switchboards for the essential safety related circuits, making a total of 65 circuit breakers plus FSD panels. (Author)

Increased hydrazine during partial nitritation process in upflow air-lift reactor fed with supernatant of anaerobic digester effluent

Energy Technology Data Exchange (ETDEWEB)

Choi, Jeongdong [University of Alberta, Alberta (Canada); Jung, Sokhee [Samsung SDS, Seoul (Korea, Republic of); Ahn, Young-Ho [Yeungnam University, Gyungsan (Korea, Republic of)

2013-06-15

The optimal balance of ammonium and nitrite is essential for successful operation of the subsequent anammox process. We conducted a partial nitritation experiment using an upflow air-lift reactor to provide operational parameters for achieving the optimal ratio of ammonium to nitrite, by feeding supernatant of anaerobic digester effluent, high-nitrogen containing rejection water. Semi-continuous operation results show that HRT should be set between 15 and 17 hours to achieve the optimum ration of 1.3 of NO{sub 2}-N/NH{sub 4}-N. In the UAR, nitritation was the dominant reaction due to high concentration of ammonia and low biodegradable organics. The influent contained low concentrations of hydroxylamine and hydrazine. However, hydrazine increased during partial nitritation by ⁓60-130% although there was no potential anammox activity in the reactor. The partial nitritation process successfully provided the ratio of nitrogen species for the anammox reaction, and relived the nitrite restraint on the anammox activity by increasing hydrazine concentration.

30 CFR 57.22209 - Auxiliary fans (I-C mines).

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Auxiliary fans (I-C mines). 57.22209 Section 57... Standards for Methane in Metal and Nonmetal Mines Ventilation § 57.22209 Auxiliary fans (I-C mines). Electric auxiliary fans shall be approved by MSHA under the applicable requirements of 30 CFR part 18...

Improving Energy Efficiency of Auxiliaries

International Nuclear Information System (INIS)

Carl T. Vuk

2001-01-01

The summaries of this report are: Economics Ultimately Dictates Direction; Electric Auxiliaries Provide Solid Benefits. The Impact on Vehicle Architecture Will be Important; Integrated Generators With Combined With Turbo Generators Can Meet the Electrical Demands of Electric Auxiliaries; Implementation Will Follow Automotive 42V Transition; Availability of Low Cost Hardware Will Slow Implementation; Industry Leadership and Cooperation Needed; Standards and Safety Protocols Will be Important. Government Can Play an Important Role in Expediting: Funding Technical Development; Incentives for Improving Fuel Economy; Developing Standards, Allowing Economy of Scale; and Providing Safety Guidelines

Dihydropyrimidine based hydrazine dihydrochloride derivatives as potent urease inhibitors.

Science.gov (United States)

Khan, Ajmal; Hashim, Jamshed; Arshad, Nuzhat; Khan, Ijaz; Siddiqui, Naureen; Wadood, Abdul; Ali, Muzaffar; Arshad, Fiza; Khan, Khalid Mohammed; Choudhary, M Iqbal

2016-02-01

Four series of heterocyclic compounds 4-dihydropyrimidine-2-thiones 7-12 (series A), N,S-dimethyl-dihydropyrimidines 13-18 (series B), hydrazine derivatives of dihydropyrimidine 19-24 (series C), and tetrazolo dihydropyrimidine derivatives 25-30 (series D), were synthesized and evaluated for in vitro urease inhibitory activity. The series B-D were first time examined for urease inhibition. Series A and C were found to be significantly active with IC50 values between 34.7-42.9 and 15.0-26.0 μM, respectively. The structure-activity relationship showed that the free S atom and hydrazine moiety are the key pharmacophores against urease enzyme. The kinetic studies of the active series A (7-12) and C (19-24) were carried out to determine their modes of inhibition and dissociation constants Ki. Compounds of series A (7-12) and series C (19-24) showed a mixed-type of inhibition with Ki values ranging between 15.76-25.66 and 14.63-29.42 μM, respectively. The molecular docking results showed that all the active compounds of both series have significant binding interactions with the active sites specially Ni-ion of the urease enzyme. Cytotoxicity of all series A-D was also evaluated against mammalian mouse fibroblast 3T3 cell lines, and no toxicity was observed in cellular model. Copyright © 2016 Elsevier Inc. All rights reserved.

Redox Response of Reduced Graphene Oxide-Modified Glassy Carbon Electrodes to Hydrogen Peroxide and Hydrazine

Directory of Open Access Journals (Sweden)

Jun-ichi Anzai

2013-05-01

Full Text Available The surface of a glassy carbon (GC electrode was modified with reduced graphene oxide (rGO to evaluate the electrochemical response of the modified GC electrodes to hydrogen peroxide (H2O2 and hydrazine. The electrode potential of the GC electrode was repeatedly scanned from −1.5 to 0.6 V in an aqueous dispersion of graphene oxide (GO to deposit rGO on the surface of the GC electrode. The surface morphology of the modified GC electrode was characterized by scanning electron microscopy (SEM and atomic force microscopy (AFM. SEM and AFM observations revealed that aggregated rGO was deposited on the GC electrode, forming a rather rough surface. The rGO-modified electrodes exhibited significantly higher responses in redox reactions of H2O2 as compared with the response of an unmodified GC electrode. In addition, the electrocatalytic activity of the rGO-modified electrode to hydrazine oxidation was also higher than that of the unmodified GC electrode. The response of the rGO-modified electrode was rationalized based on the higher catalytic activity of rGO to the redox reactions of H2O2 and hydrazine. The results suggest that rGO-modified electrodes are useful for constructing electrochemical sensors.

Recent Advances in Airframe-Propulsion Concepts with Distributed Propulsion

OpenAIRE

Isikveren , A.T.; Seitz , A.; Bijewitz , J.; Hornung , M.; Mirzoyan , A.; Isyanov , A.; Godard , J.L.; Stückl , S.; Van Toor , J.

2014-01-01

International audience; This paper discusses design and integration associated with distributed propulsion as a means of providing motive power for future aircraft concepts. The technical work reflects activities performed within a European Commission funded Framework 7 project entitled Distributed Propulsion and Ultra-high By-Pass Rotor Study at Aircraft Level, or, DisPURSAL. In this instance, the approach of distributed propulsion includes one unique solution that integrates the fuselage wi...

Liquid-Phase Heat-Release Rates of the Systems Hydrazine-Nitric Acid and Unsymmetrical Dimethylhydrazine-Nitric Acid

Science.gov (United States)

Somogyi, Dezso; Feiler, Charles E.

1960-01-01

The initial rates of heat release produced by the reactions of hydrazine and unsymmetrical dimethylhydrazine with nitric acid were determined in a bomb calorimeter under conditions of forced mixing. Fuel-oxidant weight ratio and injection velocity were varied. The rate of heat release apparently depended on the interfacial area between the propellants. Above a narrow range of injection velocities representing a critical amount of interfacial area, the rates reached a maximum and were almost constant with injection velocity. The maximum rate for hydrazine was about 70 percent greater than that for unsymmetrical dimethylhydrazine. The total heat released did not vary with mixture ratio over the range studied.

The installation of helium auxiliary systems in HTGR

International Nuclear Information System (INIS)

Qin Zhenya; Fu Xiaodong

1993-01-01

The inert gas Helium was chosen as reactor coolant in high temperature gas coolant reactor, therefore a set of Special and uncomplex helium auxiliary systems will be installed, the safe operation of HTR-10 can be safeguarded. It does not effect the inherent safety of HTR-10 MW if any one of all those systems were damaged during operation condition. This article introduces the design function and the system principle of all helium auxiliary systems to be installed in HTR-10. Those systems include: helium purification and its regeneration system, helium supply and storage system, pressure control and release system of primary system, dump system for helium auxiliary system and fuel handling, gaseous waste storage system, water extraction system for helium auxiliary systems and evacuation system for primary system

Auxiliary resonant DC tank converter

Science.gov (United States)

Peng, Fang Z.

2000-01-01

An auxiliary resonant dc tank (ARDCT) converter is provided for achieving soft-switching in a power converter. An ARDCT circuit is coupled directly across a dc bus to the inverter to generate a resonant dc bus voltage, including upper and lower resonant capacitors connected in series as a resonant leg, first and second dc tank capacitors connected in series as a tank leg, and an auxiliary resonant circuit comprising a series combination of a resonant inductor and a pair of auxiliary switching devices. The ARDCT circuit further includes first clamping means for holding the resonant dc bus voltage to the dc tank voltage of the tank leg, and second clamping means for clamping the resonant dc bus voltage to zero during a resonant period. The ARDCT circuit resonantly brings the dc bus voltage to zero in order to provide a zero-voltage switching opportunity for the inverter, then quickly rebounds the dc bus voltage back to the dc tank voltage after the inverter changes state. The auxiliary switching devices are turned on and off under zero-current conditions. The ARDCT circuit only absorbs ripples of the inverter dc bus current, thus having less current stress. In addition, since the ARDCT circuit is coupled in parallel with the dc power supply and the inverter for merely assisting soft-switching of the inverter without participating in real dc power transmission and power conversion, malfunction and failure of the tank circuit will not affect the functional operation of the inverter; thus a highly reliable converter system is expected.

The Ion Propulsion System for the Solar Electric Propulsion Technology Demonstration Mission

Science.gov (United States)

Herman, Daniel A.; Santiago, Walter; Kamhawi, Hani; Polk, James E.; Snyder, John Steven; Hofer, Richard R.; Parker, J. Morgan

2015-01-01

The Asteroid Redirect Robotic Mission is a candidate Solar Electric Propulsion Technology Demonstration Mission whose main objectives are to develop and demonstrate a high-power solar electric propulsion capability for the Agency and return an asteroidal mass for rendezvous and characterization in a companion human-crewed mission. The ion propulsion system must be capable of operating over an 8-year time period and processing up to 10,000 kg of xenon propellant. This high-power solar electric propulsion capability, or an extensible derivative of it, has been identified as a critical part of an affordable, beyond-low-Earth-orbit, manned-exploration architecture. Under the NASA Space Technology Mission Directorate the critical electric propulsion and solar array technologies are being developed. The ion propulsion system being co-developed by the NASA Glenn Research Center and the Jet Propulsion Laboratory for the Asteroid Redirect Vehicle is based on the NASA-developed 12.5 kW Hall Effect Rocket with Magnetic Shielding (HERMeS0 thruster and power processing technologies. This paper presents the conceptual design for the ion propulsion system, the status of the NASA in-house thruster and power processing activity, and an update on flight hardware.

Coordination and propulsion and non-propulsion phases in 100 meter breaststroke swimming.

Science.gov (United States)

Strzała, Marek; Krężałek, Piotr; Kucia-Czyszczoń, Katarzyna; Ostrowski, Andrzej; Stanula, Arkadiusz; Tyka, Anna K; Sagalara, Andrzej

2014-01-01

The main purpose of this study was to analyze the coordination, propulsion and non-propulsion phases in the 100 meter breaststroke race. Twenty-seven male swimmers (15.7 ± 1.98 years old) with the total body length (TBL) of 247.0 ± 10.60 [cm] performed an all-out 100 m breaststroke bout. The bouts were recorded with an underwater camera installed on a portable trolley. The swimming kinematic parameters, stroke rate (SR) and stroke length (SL), as well as the coordination indices based on propulsive or non-propulsive movement phases of the arms and legs were distinguished. Swimming speed (V100surface breast) was associated with SL (R = 0.41, p study were measured using partial correlations with controlled age. SL interplayed negatively with the limbs propulsive phase Overlap indicator (R = -0.46, p propulsion Glide indicator. The propulsion in-sweep (AP3) phase of arms and their non-propulsion partial air recovery (ARair) phase interplayed with V100surface breast (R = 0.51, p < 0.05 and 0.48 p < 0.05) respectively, displaying the importance of proper execution of this phase (AP3) and in reducing the resistance recovery phases in consecutive ones.

Interactions of hydrazine, ferrous sulfamate, sodium nitrite, and nitric acid in nuclear fuel processing solutions

International Nuclear Information System (INIS)

Gray, L.W.

1977-03-01

Hydrazine and ferrous sulfamate are used as reductants in a variety of nuclear fuel processing solutions. An oxidant, normally sodium nitrite, must frequently be added to these nitric acid solutions before additional processing can proceed. The interactions of these four chemicals have been studied under a wide variety of conditions using a 2/sup p/ factorial experimental design to determine relative reaction rates for desired reactions and side reactions. Evidence for a hydrazine-stabilized, sulfamic acid--nitrous acid intermediate was obtained; this intermediate can hydrolyze to ammonia or decompose to nitrogen. The oxidation of Fe 2+ by NO 2 - was shown to proceed at about the same rate as the scavenging of NO 2 - by sulfamic acid. Various side reactions are discussed

Space Shuttle 750 psi Helium Regulator Application on Mars Science Laboratory Propulsion

Science.gov (United States)

Mizukami, Masashi; Yankura, George; Rust, Thomas; Anderson, John R.; Dien, Anthony; Garda, Hoshang; Bezer, Mary Ann; Johnson, David; Arndt, Scott

2009-01-01

The Mars Science Laboratory (MSL) is NASA's next major mission to Mars, to be launched in September 2009. It is a nuclear powered rover designed for a long duration mission, with an extensive suite of science instruments. The descent and landing uses a unique 'skycrane' concept, where a rocket-powered descent stage decelerates the vehicle, hovers over the ground, lowers the rover to the ground on a bridle, then flies a safe distance away for disposal. This descent stage uses a regulated hydrazine propulsion system. Performance requirements for the pressure regulator were very demanding, with a wide range of flow rates and tight regulated pressure band. These indicated that a piloted regulator would be needed, which are notoriously complex, and time available for development was short. Coincidentally, it was found that the helium regulator used in the Space Shuttle Orbiter main propulsion system came very close to meeting MSL requirements. However, the type was out of production, and fabricating new units would incur long lead times and technical risk. Therefore, the Space Shuttle program graciously furnished three units for use by MSL. Minor modifications were made, and the units were carefully tuned to MSL requirements. Some of the personnel involved had built and tested the original shuttle units. Delta qualification for MSL application was successfully conducted on one of the units. A pyrovalve slam start and shock test was conducted. Dynamic performance analyses for the new application were conducted, using sophisticated tools developed for Shuttle. Because the MSL regulator is a refurbished Shuttle flight regulator, it will be the only part of MSL which has physically already been in space.

Non-Toxic HAN Monopropellant Propulsion, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Non-toxic monopropellants have been developed that provide better performance than toxic hydrazine. Formulations based on hydroxylammonium nitrate (HAN) have...

The influence of ultrasound on the reduction of plutonium (4) by hydrazine and hydroxylamine in nitric acid and hydrochloric acid media

International Nuclear Information System (INIS)

Nikonov, M.V.; Shilov, V.P.

1989-01-01

Spectrophotometric method was used to study reduction of Pu(4) by hydrazine and hydroxylamine in HNO 3 and HCl solutions under the effect of ultrasonic waves at 18-20 deg C. It is shown that reaction of Pu(4) with hydrazine is accelerated in ultrasonic field approximately 10 times; ultrasound doesn't produce noticeable effect on behaviour of the actinoid in the case of hydroxylamine

Nuclear propulsion for orbital transfer

International Nuclear Information System (INIS)

Beale, G.A.; Lawrence, T.J.

1989-01-01

The state of the art in nuclear propulsion for orbital transfer is discussed. Cryogenic propulsion, electric propulsion, solar-thermal propulsion and direct nuclear propulsion are examined in this context. New technologies with exceptional promise are addressed, emphasizing the particle test bed nuclear engine

Chemical synthesis, characterization and electro-oxidation of hydrazine via a carbon paste electrode modified with poly (P-phenylendiamine/Al2O3) nanocomposite

International Nuclear Information System (INIS)

Emamgholizadeh, Abbas; Omrani, Abdollah; Rostami, Abbas Ali

2012-01-01

Highlights: ► A novel nanocomposite based on poly (P-phenylendiamine)/alumina was synthesized. ► It was observed that the nanocomposite increased the surface catalytic activity of CPE toward oxidation of hydrazine. ► The EIS measurements showed that the values of R ct decreases by the nanoalumina presence. - Abstract: In this article, the chemical synthesis and characterization of Al 2 O 3 nanoparticles dispersed into poly (P-phenylendiamine) (PpDP) was reported. The morphology, conductivity and structure of the nanocomposite was characterized by scanning electron microscopy (SEM), four probe testing and XRD experiment, respectively. Catalytic activity and stability for the oxidation of hydrazine were studied by using cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The results show that the nanocomposite significantly enhances the effective surface area and the catalytic activity of the CPE (carbon paste electrode) for oxidation of hydrazine. The results obtained confirmed that the dispersion of the Al 2 O 3 particles is connected with catalytic response to a higher activity. The nanotubular morphology of poly (P-phenylendiamine) helps in the effective dispersion of Al 2 O 3 particles facilitating the easier access of hydrazine to the catalytic sites. The poly (P-phenylendiamine) nanotubes modified with Al 2 O 3 nanoparticles cause a great increase in electroactivity and the electro-catalytic properties of CPE for hydrazine oxidation.

47 CFR 74.601 - Classes of TV broadcast auxiliary stations.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Classes of TV broadcast auxiliary stations. 74... Television Broadcast Auxiliary Stations § 74.601 Classes of TV broadcast auxiliary stations. (a) TV pickup stations. A land mobile station used for the transmission of TV program material and related communications...

Propulsion for CubeSats

Science.gov (United States)

Lemmer, Kristina

2017-05-01

At present, very few CubeSats have flown in space featuring propulsion systems. Of those that have, the literature is scattered, published in a variety of formats (conference proceedings, contractor websites, technical notes, and journal articles), and often not available for public release. This paper seeks to collect the relevant publically releasable information in one location. To date, only two missions have featured propulsion systems as part of the technology demonstration. The IMPACT mission from the Aerospace Corporation launched several electrospray thrusters from Massachusetts Institute of Technology, and BricSAT-P from the United States Naval Academy had four micro-Cathode Arc Thrusters from George Washington University. Other than these two missions, propulsion on CubeSats has been used only for attitude control and reaction wheel desaturation via cold gas propulsion systems. As the desired capability of CubeSats increases, and more complex missions are planned, propulsion is required to accomplish the science and engineering objectives. This survey includes propulsion systems that have been designed specifically for the CubeSat platform and systems that fit within CubeSat constraints but were developed for other platforms. Throughout the survey, discussion of flight heritage and results of the mission are included where publicly released information and data have been made available. Major categories of propulsion systems that are in this survey are solar sails, cold gas propulsion, electric propulsion, and chemical propulsion systems. Only systems that have been tested in a laboratory or with some flight history are included.

Effects of Auxiliary-Source Connection in Multichip Power Module

DEFF Research Database (Denmark)

Li, Helong; Munk-Nielsen, Stig; Wang, Xiongfei

2017-01-01

the power loop and the gate loop like how the Kelvin-source connection does, owing to their involvement in the loop of the power source current. Three effects of the auxiliary-source connections are then analyzed, which are 1) the common source stray inductance reduction, 2) the transient drain......Auxiliary-source bond wires and connections are widely used in power modules with paralleled MOSFETs or IGBTs. This paper investigates the operation mechanism of the auxiliary-source connections in multichip power modules. It reveals that the auxiliary-source connections cannot fully decouple......-source current imbalance mitigation, and 3) the influence on the steady-state current distribution. Lastly, simulations and experimental results validate the theoretical analysis....

30 CFR 57.8534 - Shutdown or failure of auxiliary fans.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shutdown or failure of auxiliary fans. 57.8534... Ventilation Underground Only § 57.8534 Shutdown or failure of auxiliary fans. (a) Auxiliary fans installed and... fan maintenance or fan adjustments where air quality is maintained in compliance with the applicable...

Effect of workload setting on propulsion technique in handrim wheelchair propulsion.

Science.gov (United States)

van Drongelen, Stefan; Arnet, Ursina; Veeger, Dirkjan H E J; van der Woude, Lucas H V

2013-03-01

To investigate the influence of workload setting (speed at constant power, method to impose power) on the propulsion technique (i.e. force and timing characteristics) in handrim wheelchair propulsion. Twelve able-bodied men participated in this study. External forces were measured during handrim wheelchair propulsion on a motor driven treadmill at different velocities and constant power output (to test the forced effect of speed) and at power outputs imposed by incline vs. pulley system (to test the effect of method to impose power). Outcome measures were the force and timing variables of the propulsion technique. FEF and timing variables showed significant differences between the speed conditions when propelling at the same power output (p propulsion technique parameters despite an overall constant power output. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.

Derivatization Ion Chromatography for the Determination of Monoethanolamine in Presence of Hydrazine in PHWR Steam-Water Circuits

Directory of Open Access Journals (Sweden)

Ayushi D.

2011-01-01

Full Text Available A simple, rapid and accurate method for the determination of monoethanolamine (MEA in PHWR steam-water circuits has been developed. MEA is added in the feed water to provide protection against corrosion while hydrazine is added to scavenge dissolved oxygen. The quantitative determination of MEA in presence of hydrazine was accomplished using derivatization ion chromatography with conductometric detection in nonsuppressed mode. A Metrosep cation 1-2 analytical column and a Metrosep cartridge were used for cation separation. A mixture of 4 mM tartaric acid, 20% acetone and 0.05 mM HNO3 was used as eluent. Acetone in the mobile phase leads to the formation of different derivatives with MEA and hydrazine. The interferences due Na+ and NH4 + were eliminated by adopting a simple pretreatment procedure employing OnGuard-H cartridge. The limit of detection limit of MEA was 0.1 μg mL−1 and the relative standard deviation was 2% for the overall method. The recovery of MEA added was in the range 95%–102%. The method was applied to the determination of MEA in steam generator water samples.

Auxiliary System Load Schemes in Large Thermal and Nuclear Power Plants

International Nuclear Information System (INIS)

Kuzle, I.; Bosnjak, D.; Pandzic, H.

2010-01-01

Uninterrupted auxiliary system power supply in large power plants is a key factor for normal operation, transient states, start-ups and shutdowns and particularly during fault conditions. Therefore, there are many challenges in designing the main electrical system as well as the auxiliary systems power supply. Depending upon the type of fuel used and the environmental control system required, a thermal power plant may consume as much as 10% of its total generation for auxiliary power, while a nuclear power plant may require only 4 - 6% auxiliaries. In general, the larger the power generating plant, the higher the voltage selected for the AC auxiliary electric system. Most stations in the 75 to 500 MW range utilize 4,2 kV as the base auxiliary system voltage. Large generating stations 500 - 1000 MW and more use voltage levels of 6,9 kV and more. Some single dedicated loads such as electric driven boiler feed pumps are supplied ba a 13,8 kV bus. While designing the auxiliary electric system, the following areas must be considered: motor starting requirements, voltage regulation requirements, short-circuit duty requirements, economic considerations, reliability and alternate sources. Auxiliary power supply can't be completely generalized and each situation should be studied on its own merits to determine the optimal solution. Naturally, nuclear power plants have more reliability requirements and safety design criteria. Main coolant-pump power supply and continuity of service to other vital loads deserve special attention. This paper presents an overview of some up-to-date power plant auxiliary load system concepts. The main types of auxiliary loads are described and the electric diagrams of the modern auxiliary system supply concepts are given. Various alternative sources of auxiliary electrical supply are considered, the advantages and disadvantages of these are compared and proposals are made for high voltage distribution systems around the thermal and nuclear plant

Nuclear reactor auxiliary heat removal system

International Nuclear Information System (INIS)

Thompson, R.E.; Pierce, B.L.

1977-01-01

An auxiliary heat removal system to remove residual heat from gas-cooled nuclear reactors is described. The reactor coolant is expanded through a turbine, cooled in a heat exchanger and compressed by a compressor before reentering the reactor coolant. The turbine powers both the compressor and the pump which pumps a second fluid through the heat exchanger to cool the reactor coolant. A pneumatic starter is utilized to start the turbine, thereby making the auxiliary heat removal system independent of external power sources

Builtin vs. auxiliary detection of extrapolation risk.

Energy Technology Data Exchange (ETDEWEB)

Munson, Miles Arthur; Kegelmeyer, W. Philip,

2013-02-01

A key assumption in supervised machine learning is that future data will be similar to historical data. This assumption is often false in real world applications, and as a result, prediction models often return predictions that are extrapolations. We compare four approaches to estimating extrapolation risk for machine learning predictions. Two builtin methods use information available from the classification model to decide if the model would be extrapolating for an input data point. The other two build auxiliary models to supplement the classification model and explicitly model extrapolation risk. Experiments with synthetic and real data sets show that the auxiliary models are more reliable risk detectors. To best safeguard against extrapolating predictions, however, we recommend combining builtin and auxiliary diagnostics.

Distributed Propulsion Vehicles

Science.gov (United States)

Kim, Hyun Dae

2010-01-01

Since the introduction of large jet-powered transport aircraft, the majority of these vehicles have been designed by placing thrust-generating engines either under the wings or on the fuselage to minimize aerodynamic interactions on the vehicle operation. However, advances in computational and experimental tools along with new technologies in materials, structures, and aircraft controls, etc. are enabling a high degree of integration of the airframe and propulsion system in aircraft design. The National Aeronautics and Space Administration (NASA) has been investigating a number of revolutionary distributed propulsion vehicle concepts to increase aircraft performance. The concept of distributed propulsion is to fully integrate a propulsion system within an airframe such that the aircraft takes full synergistic benefits of coupling of airframe aerodynamics and the propulsion thrust stream by distributing thrust using many propulsors on the airframe. Some of the concepts are based on the use of distributed jet flaps, distributed small multiple engines, gas-driven multi-fans, mechanically driven multifans, cross-flow fans, and electric fans driven by turboelectric generators. This paper describes some early concepts of the distributed propulsion vehicles and the current turboelectric distributed propulsion (TeDP) vehicle concepts being studied under the NASA s Subsonic Fixed Wing (SFW) Project to drastically reduce aircraft-related fuel burn, emissions, and noise by the year 2030 to 2035.

Green Applications for Space Power Project

Science.gov (United States)

Robinson, Joel (Principal Investigator)

2014-01-01

Spacecraft propulsion and power for many decades has relied on Hydrazine monopropellant technology for auxiliary power units (APU), orbital circularization, orbit raising/lowering and attitude control. However, Hydrazine is toxic and therefore requires special ground handling procedures to ensure launch crew safety. The Swedish Company ECAPS has developed a technology based upon the propellant Ammonium Dinitramide (ADN) that offers higher performance, higher density and reduced ground handling support than Hydrazine. This blended propellant is called LMP-103S. Currently, the United States Air Force (USAF) is pursuing a technology based on Hydroxyl Ammonium Nitrate (HAN, otherwise known as AF-M315E) with industry partners Aerojet and Moog. Based on the advantages offered by these propellants, MSFC should explore powering APU's with these propellants. Due to the availability of space hardware, the principal investigator has found a collection of USAF hardware, that will act as a surrogate, which operates on a Hydrazine derivative. The F-16 fighter jet uses H-70 or 30% diluted Hydrazine for an Emergency Power Unit (EPU) which supplies power to the plane. The PI has acquired two EPU's from planes slated for destruction at the Davis Monthan AFB. This CIF will include a partnership with 2 other NASA Centers who are individually seeking seed funds from their respective organizations: Kennedy Space Center (KSC) and Dryden Flight Research Center (DFRC). KSC is preparing for future flights from their launch pads that will utilize green propellants and desire a low-cost testbed in which to test and calibrate new leak detection sensors. DFRC has access to F-16's which can be used by MSFC & KSC to perform a ground test that demonstrates emergency power supplied to the jet. Neither of the green propellant alternatives have been considered nor evaluated for an APU application. Work has already been accomplished to characterize and obtain the properties of these 2 propellants

14 CFR 25.1142 - Auxiliary power unit controls.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Auxiliary power unit controls. 25.1142... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Powerplant Controls and Accessories § 25.1142 Auxiliary power unit controls. Means must be provided on the flight deck for starting...

14 CFR 23.1142 - Auxiliary power unit controls.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Auxiliary power unit controls. 23.1142... Powerplant Controls and Accessories § 23.1142 Auxiliary power unit controls. Means must be provided on the... power unit. [Doc. No. 26344, 58 FR 18974, Apr. 9, 1993] ...

14 CFR 29.1142 - Auxiliary power unit controls.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Auxiliary power unit controls. 29.1142... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Powerplant Controls and Accessories § 29.1142 Auxiliary power unit controls. Means must be provided on the flight deck for starting...

On hydrazine oxidation in nitric acid media

International Nuclear Information System (INIS)

Zil'berman, B.Ya.; Lelyuk, G.A.; Mashkin, A.N.; Yasnovitskaya, A.L.

1988-01-01

Yield of products of radiolytic ( 60 Co gamma radiation) and chemical hydrazine (HZ) oxidation in nitric acid media is studied. Under radiolyte HZ oxidation by nitric acid hydrazoic acid, ammonia and nitrogen appear to be the reaction products. HN 3 yield maximum under HZN oxidation makes up ∼ 0.35 mol per a mol of oxiduzed HZN. Under chemical oxidation HZN is oxidized by HNO 3 according to reaction catalysed by technetium HN 3 yield makes up ∼ 0.35 mol per a mol of oxidized HZN. Radiation-chemical oxidation of HN 3 proceeds up to its complete decomposition, decomposition rate is comparable with HZ oxidation rate. Under the chemical oxidation HN 3 is more stable, it is slowly decomposed after complete HZ decomposition

Effect of niobium addition in support catalysts applied in satellite propulsion

Energy Technology Data Exchange (ETDEWEB)

Soares, M.S., E-mail: marciosteinmetz@hotmail.com.br [Space Research National Institute, Combustion & Propulsion Associated Laboratory (Brazil); University of São Paulo, Lorena Engineering School, Materials Engineering Dept. (Brazil); Barbosa, R.D. [Space Research National Institute, Combustion & Propulsion Associated Laboratory (Brazil); University of São Paulo, Lorena Engineering School, Chemical Engineering Dept. (Brazil); Cruz, G.M. da; Rodrigues, J.A.J. [Space Research National Institute, Combustion & Propulsion Associated Laboratory (Brazil); Ribeiro, S. [University of São Paulo, Lorena Engineering School, Materials Engineering Dept. (Brazil)

2017-03-01

Catalysts composed of iridium as the active phase dispersed in aluminum oxide (Ir/Al{sub 2}O{sub 3}) are used in propulsion systems that employ hydrazine as monopropellant in the control of satellite orbit and attitude. The aluminum oxide (Al{sub 2}O{sub 3}) utilized as support must present high values of specific surface area, pore volume, and crush strength. The niobium effect was evaluated in this work, in its oxide form (Nb{sub 2}O{sub 5}), by 3 different methods: with the employment of a NbCl{sub 5} precursor solution, by wet impregnation and dry impregnation of an alumina obtained from a mixture of gibbsite and boehmite and by physical mixing of gibbsite and hydrated niobium oxide, both autoclaved separately. Aluminum oxides were prepared in both cases containing Nb{sub 2}O{sub 5} contents of 10, 20, and 30% w/w. The acid impregnating NbCl{sub 5} solution in the wet impregnation method caused a strong attack to the Al{sub 2}O{sub 3} support, altering and compromising its initial structure and morphology. This process did not occur in the supports prepared by dry impregnation. However, results indicated that the use of this methodology with Nb{sub 2}O{sub 5} contents of 20% and 30%, caused an extensive coverage of the support by Nb{sub 2}O{sub 5}, modifying the nature and amount of alumina sites responsible for anchorage of the iridium precursor. In the case of supports prepared through physical mixture (Nb{sub 2}O{sub 5}-Al{sub 2}O{sub 3}) from aluminum hydroxide and niobium acid precursor compounds, with both being previously autoclaved separately, the 20% and 30% Nb{sub 2}O{sub 5} contents presented the most promising properties, since the binder effect caused by amorphous Nb{sub 2}O{sub 5} increased the crush strength of the support, without compromising the aluminum oxide morphology and texture. Despite of existence of stronger acid sites due to the addition of niobium oxide to aluminum oxide, no increase in the acidity of the materials was observed due

Dedicated auxiliary power units for Hybrid Electric Vehicles

NARCIS (Netherlands)

Mourad, S.; Weijer, C.J.T. van de

1998-01-01

The use of a dedicated auxiliary power unit is essential to utilize the potential that hybrid vehicles offer for efficient and ultra-clean transportation. An example of a hybrid project at the TNO Road-Vehicles Research Institute shows the development and the results of a dedicated auxiliary power

Diesel fueled ship propulsion fuel cell demonstration project

Energy Technology Data Exchange (ETDEWEB)

Kumm, W.H. [Arctic Energies Ltd., Severna Park, MD (United States)

1996-12-31

The paper describes the work underway to adapt a former US Navy diesel electric drive ship as a 2.4 Megawatt fuel cell powered, US Coast Guard operated, demonstrator. The Project will design the new configuration, and then remove the four 600 kW diesel electric generators and auxiliaries. It will design, build and install fourteen or more nominal 180 kW diesel fueled molten carbonate internal reforming direct fuel cells (DFCs). The USCG cutter VINDICATOR has been chosen. The adaptation will be carried out at the USCG shipyard at Curtis Bay, MD. A multi-agency (state and federal) cooperative project is now underway. The USCG prime contractor, AEL, is performing the work under a Phase III Small Business Innovation Research (SBIR) award. This follows their successful completion of Phases I and II under contract to the US Naval Sea Systems (NAVSEA) from 1989 through 1993 which successfully demonstrated the feasibility of diesel fueled DFCs. The demonstrated marine propulsion of a USCG cutter will lead to commercial, naval ship and submarine applications as well as on-land applications such as diesel fueled locomotives.

Synthesis of the row of new functional derivatives of 7-arylalkyl-8-hydrazine theophyllines

Directory of Open Access Journals (Sweden)

Dmytro Korobko

2016-03-01

Full Text Available Hydrazine functional derivatives are widely used in medical practice as remedies applied for pharmacotherapy of depression, infection diseases, hypertension, diabetes, etc. It is worth mentioning that among obtained 7-R-8-hydrazine derivatives of 1,3-dimethylxantine promising substances have been identified. Due to the fact that literature sources display only results of occasional studies of the reactions between 7-R-8-hydrazine theophyllines and mono- or dicarbonyle substances, the use of other keto reagents for xanthine bicycle at 8th position functionalization will allow to explore synthetic potential of the last one, and with high probability may lead to obtaining original biologically active substances.Aim. To study types of reaction between 8-hydrazinyl-1,3-dimethyl-7-aryl alkyl-1H-purine-2,6(3H,7H-diones and a number of carbonyl containing reagents.Methods. A nucleophilic addition reaction followed by dehydration or ethanol splitting was used, as well as the complex of the modern analysis methods to confirm the structure and individuality of the synthesized substances.Results. Different directions of 8-hydrazinyl-1,3,-dimethyl-7(fenetyl-, 3-phenylpropyl-, 3-phenylalyl-1H-purine-2,6(3H,7H-diones chemical transformations in reactions with the appropriate carbonyl containing compounds have been studied experimentally. The structure of synthesized substances was confirmed by chromatography/mass and 1H NMR spectroscopy.Conclusion. The group of 7-arylalkyl-8-(3,5-R,R1-pyrazole-1-yltheophyllines, consisting of two functionally substituted bioactive heterocycles, has been synthesized by reaction between initial substances and selected mono- and dicarbonyl compounds

Nuclear electric propulsion: An integral part of NASA's nuclear propulsion project

International Nuclear Information System (INIS)

Stone, J.R.

1992-01-01

NASA has initiated a technology program to establish the readiness of nuclear propulsion technology for the Space Exploration Initiative (SEI). This program was initiated with a very modest effort identified with nuclear thermal propulsion (NTP); however, nuclear electric propulsion (NEP) is also an integral part of this program and builds upon NASA's Base Research and Technology Program in power and electric propulsion as well as the SP-100 space nuclear power program. Although the Synthesis Group On America's SEI has identified NEP only as an option for cargo missions, recent studies conducted by NASA-Lewis show that NEP offers the potential for early manned Mars missions as well. Lower power NEP is also of current interest for outer planetary robotic missions. Current plans are reviewed for the overall nuclear propulsion project, with emphasis on NEP and those elements of NTP program which have synergism with NEP

Nuclear reactors with auxiliary boiler circuit

International Nuclear Information System (INIS)

George, B.V.; Cook, R.K.

1976-01-01

A gas-cooled nuclear reactor has a main circulatory system for the gaseous coolant incorporating one or more main energy converting units, such as gas turbines, and an auxiliary circulatory system for the gaseous coolant incorporating at least one steam generating boiler arranged to be heated by the coolant after its passage through the reactor core to provide steam for driving an auxiliary steam turbine, such an arrangement providing a simplified start-up procedure also providing emergency duties associated with long term heat removal on reactor shut down

Transport in Auxiliary Heated NSTX Discharges

International Nuclear Information System (INIS)

LeBlanc, B.P.; Bell, M.G.; Bell, R.E.; Bitte, M.L.; Bourdelle, C.; Gates, D.A.; Kaye, S.M.; Maingi, R.; Menard, J.E.; Mueller, D.; Ono, M.; Paul, S.F.; Redi, M.H.; Roquemore, A.L.; Rosenberg, A.; Sabbagh, S.A.; Stutman, D.; Synakowski, E.J.; Soukhanovskii, V.A.; Wilson, J.R.

2003-01-01

The NSTX spherical torus (ST) provides a unique platform to investigate magnetic confinement in auxiliary-heated plasmas at low aspect ratio. Auxiliary power is routinely coupled to ohmically heated plasmas by deuterium neutral-beam injection (NBI) and by high-harmonic fast waves (HHFW) launch. While theory predicts both techniques to preferentially heat electrons, experiment reveals the electron temperature is greater than the ion temperature during HHFW, but the electron temperature is less than the ion temperature during NBI. In the following we present the experimental data and the results of transport analyses

Effects of hydrazine on the solvothermal synthesis of Cu2ZnSnSe4 and Cu2CdSnSe4 nanocrystals for particle-based deposition of films

International Nuclear Information System (INIS)

Chiang, Ming-Hung; Fu, Yaw-Shyan; Shih, Cheng-Hung; Kuo, Chun-Cheng; Guo, Tzung-Fang; Lin, Wen-Tai

2013-01-01

The effects of hydrazine on the synthesis of Cu 2 ZnSnSe 4 (CZTSe) and Cu 2 CdSnSe 4 (CCTSe) nanocrystals in an autoclave as a function of temperature and time were explored. On heating at 190 °C for 24-72 h, pure CZTSe and CCTSe nanocrystals could readily grow in the hydrazine-added solution, while in the hydrazine-free solution the intermediate phases such as ZnSe, Cu 2 Se, and Cu 2 SnSe 3 , and Cu 2 SnSe 3 and CdSe associated with the CZTSe and CCTSe nanocrystals grew, respectively. This result reveals that hydrazine can speed up the synthesis of pure CZTSe and CCTSe nanocrystals via a solvothermal process. The mechanisms for the hydrazine-enhanced growth of CZTSe and CCTSe nanocrystals were discussed. The pure CZTSe and CCTSe nanocrystals were subsequently fabricated to the smooth films by spin coating without further annealing in selenium atmosphere. This processing may be beneficial to the fabrication of the absorber layer for solar cells and thermoelectric devices. - Highlights: • Hydrazine enhances the growth of pure Cu 2 ZnSnSe 4 and Cu 2 CdSnSe 4 nanocrystals. • The nanocrystals can be fabricated to films by spin coating without annealing. • This solvothermal processing is promising for the fabrication of thin film devices

Manual wheelchair propulsion patterns on natural surfaces during start-up propulsion.

Science.gov (United States)

Koontz, Alicia M; Roche, Bailey M; Collinger, Jennifer L; Cooper, Rory A; Boninger, Michael L

2009-11-01

To classify propulsion patterns over surfaces encountered in the natural environment during start-up and compare selected biomechanical variables between pattern types. Case series. National Veterans Wheelchair Games, Minneapolis, MN, 2005. Manual wheelchair users (N=29). Subjects pushed their wheelchairs from a resting position over high-pile carpet, over linoleum, and up a ramp with a 5 degrees incline while propulsion kinematics and kinetics were recorded with a motion capture system and an instrumented wheel. Three raters classified the first 3 strokes as 1 of 4 types on each surface: arc, semicircular (SC), single looping over propulsion (SL), and double looping over propulsion (DL). The Fisher exact test was used to assess pattern changes between strokes and surface type. A multiple analysis of variance test was used to compare peak and average resultant force and moment about the hub, average wheel velocity, stroke frequency, contact angle, and distance traveled between stroke patterns. SL was the most common pattern used during start-up propulsion (44.9%), followed by arc (35.9%), DL (14.1%), and SC (5.1%). Subjects who dropped their hands below the rim during recovery achieved faster velocities and covered greater distances (.016propulsion patterns is a difficult task that should use multiple raters. In addition, propulsion patterns change during start-up, with an arc pattern most prevalent initially. The biomechanical findings in this study agree with current clinical guidelines that recommend training users to drop the hand below the pushrim during recovery.

PS auxiliary magnet

CERN Multimedia

CERN PhotoLab

1974-01-01

Units of the PS auxiliary magnet system. The picture shows how the new dipoles, used for vertical and horizontal high-energy beam manipulation, are split for installation and removal so that it is not necessary to break the accelerator vacuum. On the right, adjacent to the sector valve and the windings of the main magnet, is an octupole of the set.

The English Primary Auxiliary Verbs: A Linguistic Theoretical Exercise

African Journals Online (AJOL)

Nekky Umera

Abstract. Obviously, the fact remains that English Language is a sensitive Language ... Even though the English auxiliary verbs are of two kinds: Primary and Modal auxiliary ..... Therefore we are of the opinion that most speakers lack adequate.

Local charge transport properties of hydrazine reduced monolayer graphene oxide sheets prepared under pressure condition

DEFF Research Database (Denmark)

Ryuzaki, Sou; Meyer, Jakob Abild Stengaard; Petersen, Søren Vermehren

2014-01-01

Charge transport properties of chemically reduced graphene oxide (RGO) sheets prepared by treatment with hydrazine were examined using conductive atomic force microscopy. The current-voltage (I-V) characteristics of monolayer RGO sheets prepared under atmospheric pressure followed an exponentially...

Confidence Testing of Shell 405 and S-405 Catalysts in a Monopropellant Hydrazine Thruster

Science.gov (United States)

McRight, Patrick; Popp, Chris; Pierce, Charles; Turpin, Alicia; Urbanchock, Walter; Wilson, Mike

2005-01-01

As part of the transfer of catalyst manufacturing technology from Shell Chemical Company (Shell 405 catalyst manufactured in Houston, Texas) to Aerojet (S-405 manufactured in Redmond, Washington), Aerojet demonstrated the equivalence of S-405 and Shell 405 at beginning of life. Some US aerospace users expressed a desire to conduct a preliminary confidence test to assess end-of-life characteristics for S-405. NASA Marshall Space Flight Center (MSFC) and Aerojet entered a contractual agreement in 2004 to conduct a confidence test using a pair of 0.2-lbf MR-103G monopropellant hydrazine thrusters, comparing S-405 and Shell 405 side by side. This paper summarizes the formulation of this test program, explains the test matrix, describes the progress of the test, and analyzes the test results. This paper also includes a discussion of the limitations of this test and the ramifications of the test results for assessing the need for future qualification testing in particular hydrazine thruster applications.

The SMPR for the naval propulsion; Les RPMP pour la propulsion navale

Energy Technology Data Exchange (ETDEWEB)

Gauducheau, B. [Technicatome, Centre d' Etudes Nucleaires de Saclay, 91 - Gif sur Yvette (France)

2002-07-01

The first controlled application of the fissile energy was the american nuclear reactor for the ship propulsion. Since the sixties, the France begun researches to secure the independence of its nuclear propulsion program. The historical aspects, the french program management and the perspectives of the ship nuclear propulsion, are discussed in this paper. (A.L.B.)

Sol-gel process preparation and evaluation of the analytical performances of an hydrazine specific chemical sensor; Preparation par procede sol-gel et evaluation des performances analytiques d`un capteur chimique specifique de l`hydrazine

Energy Technology Data Exchange (ETDEWEB)

Gojon, C

1996-12-01

The realisation of optical fibers active chemical collector to analyze hydrazine in line, in the spent fuel reprocessing process is the subject of this work. The p.dimethyl-amino-benzaldehyde has been chosen as reagent for its chemical and optical properties. 186 refs.

Major factors in critical equipment reliability - Auxiliary systems; The development of an auxiliary system

International Nuclear Information System (INIS)

Forsthoffer, W.E.

1992-01-01

In this article, the author details the development of an actual auxiliary system in order to fully understand the function of each major component and how it contributes to the total operation and reliability of the system. Only after the function of an auxiliary system is thoroughly understood, can one proceed to discuss specifications, design audits, testing, operation and preventive maintenance. The application selected will be to develop a pressurized lubrication and steam turbine control oil system for the critical equipment unit. This example was selected since many readers will be familiar with this type and because it provides a good foundation towards understanding fluid sealing systems. In the exercise that follow, he will define the system requirements and determine the system parameters. This information will then be used for component sizing

Auxiliary bearing design considerations for gas cooled reactors

International Nuclear Information System (INIS)

Penfield, S.R. Jr.; Rodwell, E.

2001-01-01

The need to avoid contamination of the primary system, along with other perceived advantages, has led to the selection of electromagnetic bearings (EMBs) in most ongoing commercial-scale gas cooled reactor (GCR) designs. However, one implication of magnetic bearings is the requirement to provide backup support to mitigate the effects of failures or overload conditions. The demands on these auxiliary or 'catcher' bearings have been substantially escalated by the recent development of direct Brayton cycle GCR concepts. Conversely, there has been only limited directed research in the area of auxiliary bearings, particularly for vertically oriented turbomachines. This paper explores the current state-of-the-art for auxiliary bearings and the implications for current GCR designs. (author)

Energy consumption of auxiliary systems of electric cars

Directory of Open Access Journals (Sweden)

Evtimov Ivan

2017-01-01

Full Text Available The paper analyzes the power demand of the auxiliary systems of electric cars. On the basis of existing electric cars an analysis of energy consumption of different auxiliary systems is done. As a result possibilities for rational use of these systems have been proposed, which can increase the mileage per one charge of the battery.

Optimization of feed water control for auxiliary boiler

International Nuclear Information System (INIS)

Li Lingmao

2004-01-01

This paper described the feed water control system of the auxiliary boiler steam drum in Qinshan Phase III Nuclear Power Plant, analyzed the deficiency of the original configuration, and proposed the optimized configuration. The optimized feed water control system can ensure the stable and safe operation of the auxiliary boiler, and the normal operation of the users. (author)

Weight savings in aerospace vehicles through propellant scavenging

Science.gov (United States)

Schneider, Steven J.; Reed, Brian D.

1988-01-01

Vehicle payload benefits of scavenging hydrogen and oxygen propellants are addressed. The approach used is to select a vehicle and a mission and then select a scavenging system for detailed weight analysis. The Shuttle 2 vehicle on a Space Station rendezvous mission was chosen for study. The propellant scavenging system scavenges liquid hydrogen and liquid oxygen from the launch propulsion tankage during orbital maneuvers and stores them in well insulated liquid accumulators for use in a cryogenic auxiliary propulsion system. The fraction of auxiliary propulsion propellant which may be scavenged for propulsive purposes is estimated to be 45.1 percent. The auxiliary propulsion subsystem dry mass, including the proposed scavenging system, an additional 20 percent for secondary structure, an additional 5 percent for electrical service, a 10 percent weight growth margin, and 15.4 percent propellant reserves and residuals is estimated to be 6331 kg. This study shows that the fraction of the on-orbit vehicle mass required by the auxiliary propulsion system of this Shuttle 2 vehicle using this technology is estimated to be 12.0 percent compared to 19.9 percent for a vehicle with an earth-storable bipropellant system. This results in a vehicle with the capability of delivering an additional 7820 kg to the Space Station.

Weight savings in aerospace vehicles through propellant scavenging

Science.gov (United States)

Schneider, Steven J.; Reed, Brian D.

1988-05-01

Vehicle payload benefits of scavenging hydrogen and oxygen propellants are addressed. The approach used is to select a vehicle and a mission and then select a scavenging system for detailed weight analysis. The Shuttle 2 vehicle on a Space Station rendezvous mission was chosen for study. The propellant scavenging system scavenges liquid hydrogen and liquid oxygen from the launch propulsion tankage during orbital maneuvers and stores them in well insulated liquid accumulators for use in a cryogenic auxiliary propulsion system. The fraction of auxiliary propulsion propellant which may be scavenged for propulsive purposes is estimated to be 45.1 percent. The auxiliary propulsion subsystem dry mass, including the proposed scavenging system, an additional 20 percent for secondary structure, an additional 5 percent for electrical service, a 10 percent weight growth margin, and 15.4 percent propellant reserves and residuals is estimated to be 6331 kg. This study shows that the fraction of the on-orbit vehicle mass required by the auxiliary propulsion system of this Shuttle 2 vehicle using this technology is estimated to be 12.0 percent compared to 19.9 percent for a vehicle with an earth-storable bipropellant system. This results in a vehicle with the capability of delivering an additional 7820 kg to the Space Station.

Recent developments in Cope-type hydroamination reactions of hydroxylamine and hydrazine derivatives.

Science.gov (United States)

Beauchemin, André M

2013-11-07

Cope-type hydroaminations are versatile for the direct amination of alkenes, alkynes and allenes using hydroxylamines and hydrazine derivatives. These reactions occur via a concerted, 5-membered cyclic transition state that is the microscopic reverse of the Cope elimination. This article focuses on recent developments, including intermolecular variants, directed reactions, and asymmetric variants using aldehydes as tethering catalysts, and their applications in target-oriented synthesis.

Reactivity of nanoaggregations of platinum on supports of different nature in reactions of catalytic decomposition of hydrazine in acid media

International Nuclear Information System (INIS)

Anan'ev, A.V.; Boltoeva, M.Yu.; Grigor'ev, M.S.; Shilov, V.P.; Sharygin, L.M.

2006-01-01

Platinized catalysts on the basis of supports of different chemical nature are tested in reactions of catalytic hydrazine decomposition in perchloric and nitric acid solutions. In perchloric acid catalytic activity of catalysts on the basis of ceramic materials of Termoksid brand is higher of activity of catalysts on the basis of amorphous silica gel. In nitric acid solutions opposite dependence is observed. Tendency of ceramic supports to peptization in acid solutions is pointed out. Results obtained are interpreted using conceptions of energetic heterogeneity of surface atoms and hydrazine catalytic decomposition mechanisms in different media [ru

The USAF Electric Propulsion Program

National Research Council Canada - National Science Library

Spores, Ronald

1999-01-01

...: Propulsion Directorate and Air Force Office of Scientific Research (AFOSR). The Propulsion Directorate conducts electric propulsion efforts in basic research, engineering development, and space experiments...

Advanced Propulsion Study

National Research Council Canada - National Science Library

Davis, Eric

2004-01-01

... that show promise of leading to a major advance in Earth-to-orbit (ETO) propulsion. The study also reviewed and evaluated a select number of credible far-term breakthrough propulsion physics concepts pertaining...

NASA's Propulsion Research Laboratory

Science.gov (United States)

2004-01-01

The grand opening of NASA's new, world-class laboratory for research into future space transportation technologies located at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama, took place in July 2004. The state-of-the-art Propulsion Research Laboratory (PRL) serves as a leading national resource for advanced space propulsion research. Its purpose is to conduct research that will lead to the creation and development of innovative propulsion technologies for space exploration. The facility is the epicenter of the effort to move the U.S. space program beyond the confines of conventional chemical propulsion into an era of greatly improved access to space and rapid transit throughout the solar system. The laboratory is designed to accommodate researchers from across the United States, including scientists and engineers from NASA, the Department of Defense, the Department of Energy, universities, and industry. The facility, with 66,000 square feet of useable laboratory space, features a high degree of experimental capability. Its flexibility allows it to address a broad range of propulsion technologies and concepts, such as plasma, electromagnetic, thermodynamic, and propellant propulsion. An important area of emphasis is the development and utilization of advanced energy sources, including highly energetic chemical reactions, solar energy, and processes based on fission, fusion, and antimatter. The Propulsion Research Laboratory is vital for developing the advanced propulsion technologies needed to open up the space frontier, and sets the stage of research that could revolutionize space transportation for a broad range of applications.

Studies on the Mechanism of Action of Hydrazine-Induced Methylation of DNA Guanne

Science.gov (United States)

1984-10-03

and 7-methylguanine was detectable in the DNA. In another in vitro study hydrazine, formaldehyde, monomethythydrazine, methyl- nitrosourea , and...methyl- nitrosourea ; DEN, diethylnitrosamine; concentrations are expressed as millimoles per liter incubation medium. ** Ethylguanines, rather than...2436-2455. Griffith, O.W. and A. Meister, (1979), Potent and specific inhibition of glutathione synthesis by buthionine sulfoximine (S-n

Dose response of hydrazine - Deproteinated tooth enamel under blue light stimulation

International Nuclear Information System (INIS)

Yuece, Ulkue Rabia; Meric, Niyazi; Atakol, Orhan; Yasar, Fusun

2010-01-01

The beta dose response and Optically Stimulated Luminescence (OSL) signal stability characteristics of human tooth enamel deproteinated by hydrazine reagent under blue photon stimulation are reported. Removal of the protein organic component of tooth enamel resulted in a higher OSL sensitivity and slower fading of OSL signals. The effect of chemical sample preparation on the enamel sample sensitivity is discussed and further steps to make this deproteinization treatment suitable for in vitro dose reconstruction studies are suggested.

Dose response of hydrazine - Deproteinated tooth enamel under blue light stimulation

Energy Technology Data Exchange (ETDEWEB)

Yuece, Ulkue Rabia, E-mail: ulkuyuce@hotmail.co [Ankara University, Faculty of Engineering, Department of Engineering Physics, 06100, Tandogan - Ankara (Turkey); Meric, Niyazi, E-mail: meric@ankara.edu.t [Ankara University, Faculty of Engineering, Department of Engineering Physics, 06100, Tandogan - Ankara (Turkey); Atakol, Orhan, E-mail: atakol@science.ankara.edu.t [Ankara University, Science Faculty, Department of Chemistry, 06100, Tandogan - Ankara (Turkey); Yasar, Fusun, E-mail: ab121310@adalet.gov.t [Council of Forensic Medicine, Ankara Branch, Ankara (Turkey)

2010-08-15

The beta dose response and Optically Stimulated Luminescence (OSL) signal stability characteristics of human tooth enamel deproteinated by hydrazine reagent under blue photon stimulation are reported. Removal of the protein organic component of tooth enamel resulted in a higher OSL sensitivity and slower fading of OSL signals. The effect of chemical sample preparation on the enamel sample sensitivity is discussed and further steps to make this deproteinization treatment suitable for in vitro dose reconstruction studies are suggested.

Comparison of Aero-Propulsive Performance Predictions for Distributed Propulsion Configurations

Science.gov (United States)

Borer, Nicholas K.; Derlaga, Joseph M.; Deere, Karen A.; Carter, Melissa B.; Viken, Sally A.; Patterson, Michael D.; Litherland, Brandon L.; Stoll, Alex M.

2017-01-01

NASA's X-57 "Maxwell" flight demonstrator incorporates distributed electric propulsion technologies in a design that will achieve a significant reduction in energy used in cruise flight. A substantial portion of these energy savings come from beneficial aerodynamic-propulsion interaction. Previous research has shown the benefits of particular instantiations of distributed propulsion, such as the use of wingtip-mounted cruise propellers and leading edge high-lift propellers. However, these benefits have not been reduced to a generalized design or analysis approach suitable for large-scale design exploration. This paper discusses the rapid, "design-order" toolchains developed to investigate the large, complex tradespace of candidate geometries for the X-57. Due to the lack of an appropriate, rigorous set of validation data, the results of these tools were compared to three different computational flow solvers for selected wing and propulsion geometries. The comparisons were conducted using a common input geometry, but otherwise different input grids and, when appropriate, different flow assumptions to bound the comparisons. The results of these studies showed that the X-57 distributed propulsion wing should be able to meet the as-designed performance in cruise flight, while also meeting or exceeding targets for high-lift generation in low-speed flight.

Electron transport and electrocatalytic properties of MWCNT/nickel nanocomposites: hydrazine and diethylaminoethanethiol as analytical probes

CSIR Research Space (South Africa)

Adekunle, AS

2010-06-01

Full Text Available of the electrodes with the Ni and NiO nanoparticles was confirmed by techniques such as FTIR, FESEM, HRSEM, TEM, XRD, EDX and cyclic voltammetry (CV). The electrocatalytic oxidation of DEAET and hydrazine on the modified electrodes was investigated using CV...

Parallel Auxiliary Space AMG Solver for $H(div)$ Problems

Energy Technology Data Exchange (ETDEWEB)

Kolev, Tzanio V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vassilevski, Panayot S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2012-12-18

We present a family of scalable preconditioners for matrices arising in the discretization of $H(div)$ problems using the lowest order Raviart--Thomas finite elements. Our approach belongs to the class of “auxiliary space''--based methods and requires only the finite element stiffness matrix plus some minimal additional discretization information about the topology and orientation of mesh entities. Also, we provide a detailed algebraic description of the theory, parallel implementation, and different variants of this parallel auxiliary space divergence solver (ADS) and discuss its relations to the Hiptmair--Xu (HX) auxiliary space decomposition of $H(div)$ [SIAM J. Numer. Anal., 45 (2007), pp. 2483--2509] and to the auxiliary space Maxwell solver AMS [J. Comput. Math., 27 (2009), pp. 604--623]. Finally, an extensive set of numerical experiments demonstrates the robustness and scalability of our implementation on large-scale $H(div)$ problems with large jumps in the material coefficients.

Electrochemical studies on the reduction of uranyl ions in nitric acid-hydrazine media at platinum electrode

International Nuclear Information System (INIS)

Mishra, Satyabrata; Sini, K.; Mallika, C.; Kamachi Mudali, U.; Jagadeeswara Rao, Ch.

2015-01-01

Production of uranous nitrate with good conversion efficiency is one of the major steps in the aqueous reprocessing of spent fuels of nuclear reactors, as U(IV) is used for the separation of Pu from U by the selective reduction of Pu(IV) into practically non-extractable Pu(III) in aqueous streams. Electro-reduction of uranyl ions has the advantage of not introducing corrosive chemicals into the process stream. High current efficiency with maximum conversion of U(VI) to U(IV) can be achieved in continuous as well as batch mode electro-reduction, if the process is voltage-controlled rather than current controlled. As potentiostatic studies reveal the mechanism of reduction of uranyl ions in potential controlled electrolysis, the reduction behavior of uranyl ions (UO 2 2+ ) in nitric acid and nitric acid-hydrazine media were investigated by Cyclic Voltammetric (CV) and Chronopotentiometric (CP) techniques using platinum working electrode at 298 K. Heterogeneous electron transfer rate constant (ks) for uranyl reduction was estimated at a very low concentration of nitric acid (0.05 M) using Klinger and Kochi equation. Values of the diffusion coefficients were determined as a function of acidity with and without hydrazine. Reduction of uranyl ions was found to be under kinetic as well as diffusion control when the concentration of nitric acid was 0.05 M and in the absence of hydrazine. However, as the acidity of the supporting electrolyte increased, the reduction was purely under kinetic control. (author)

Auxiliary partial liver transplantation

NARCIS (Netherlands)

C.B. Reuvers (Cornelis Bastiaan)

1986-01-01

textabstractIn this thesis studies on auxiliary partial liver transplantation in the dog and the pig are reported. The motive to perform this study was the fact that patients with acute hepatic failure or end-stage chronic liver disease are often considered to form too great a risk for successful

Design and scope of impact of auxiliary lanes : technical report.

Science.gov (United States)

2014-06-01

For decades, Texas Department of Transportation districts have constructed auxiliary lanes to support interchange : ramp operations and to resolve congestion proximate to freeway entrance and exit ramps. While auxiliary lanes are : built throughout T...

Brief review on pulse laser propulsion

Science.gov (United States)

Yu, Haichao; Li, Hanyang; Wang, Yan; Cui, Lugui; Liu, Shuangqiang; Yang, Jun

2018-03-01

Pulse laser propulsion (PLP) is an advanced propulsion concept can be used across a variety of fields with a wide range of applications. PLP reflects superior payload as well as decreased launch costs in comparison with other conventional methods of producing thrust, such as chemical propulsion or electric propulsion. Numerous researchers have attempted to exploit the potential applications of PLP. This paper first reviews concepts relevant to PLP, including the propulsion modes, breakdown regimes, and propulsion efficiency; the propulsion targets for different materials with the pulse laser are then discussed in detail, including the propulsion of solid and liquid microspheres. PLP applications such as the driven microsatellite, target surface particle removal, and orbital debris removal are also discussed. Although the PLP has been applied to a variety of fields, further research is yet warranted to establish its application in the aerospace field.

NASA Electric Propulsion System Studies

Science.gov (United States)

Felder, James L.

2015-01-01

An overview of NASA efforts in the area of hybrid electric and turboelectric propulsion in large transport. This overview includes a list of reasons why we are looking at transmitting some or all of the propulsive power for the aircraft electrically, a list of the different types of hybrid-turbo electric propulsion systems, and the results of 4 aircraft studies that examined different types of hybrid-turbo electric propulsion systems.

Nuclear-microwave-electric propulsion

International Nuclear Information System (INIS)

Nordley, G.D.; Brown, W.C.

1986-01-01

Electric propulsion can move more mass through space than chemical propulsion by virtue of the higher exhaust velocities achieved by electric propulsion devices. This performance is achieved at the expense of very heavy power sources or very long trip times, which in turn create technical and economic penalties of varying severity. These penalties include: higher operations costs, delayed availability of the payload, and increased exposure to Van Allen Belt radiation. It is proposed to reduce these penalties by physically separating the power source from the propulsion and use microwave energy beaming technology, recently explored and partially developed/tested for Solar Power Satellite concept studies, as an extension cord. This paper summarizes the state of the art of the technology needed for space based beam microwave power cost/performance trades involved with the use beamed microwave/electric propulsion for some typical orbit transfer missions and offers some suggestions for additional work

Probabilistic cloning with supplementary information contained in the quantum states of two auxiliary systems

International Nuclear Information System (INIS)

Li, Lvjun; Qiu, Daowen

2007-01-01

In probabilistic cloning with two auxiliary systems, we consider and compare three different protocols for the success probabilities of cloning. We show that, in certain circumstances, it may increase the success probability to add an auxiliary system to the probabilistic cloning machine having one auxiliary system, but we always can find another cloning machine with one auxiliary system having the same success probability as that with two auxiliary systems

Possible configurations for an air independent propulsion (AIP) system for submarines based on fuel cells

International Nuclear Information System (INIS)

Bordallo, C.R.; Moreno, E.; Brey, J.J.; Garcia, C.; Sarmiento, B.; Castro, A.

2004-01-01

'Full text:' Conventional submarines employ an electric propulsion system, based on energy storage in batteries which are recharged using diesel motors connected to generator alternators. This limits their autonomy underwater given that it will be depend on the amount of energy that can be stored in the batteries; currently, a normal value is to have energy to navigate for three days at low speed. As of from the WWII, several shipyards began to carry out research on propulsion systems for submarines that would be capable of operating under anaerobic conditions, independent of the air (AIP Systems). Since then, several proposals have been considered, but there is one option that several navies are currently putting their trust in: fuel cells. The objective of this Project is to stress the different configurations that can be considered to this end, as regards the transportation of hydrogen and oxygen. From the hydrogen point of view, the possibilities of transporting it in metal hydrides or its on-board production through the reforming of different fuels (gas-oil, ethanol, methanol), are analyzed. This study also compares auxiliary systems (including CO2 removers), and proposes solutions, some of which are under development, indicating which are currently being considered to a greater extent. (author)

Possible configurations for an air independent propulsion (AIP) system for submarines based on fuel cells

Energy Technology Data Exchange (ETDEWEB)

Bordallo, C.R.; Moreno, E.; Brey, J.J.; Garcia, C.; Sarmiento, B.; Castro, A. [Hynergreen Technologies, S.A., Seville (Spain)

2004-07-01

'Full text:' Conventional submarines employ an electric propulsion system, based on energy storage in batteries which are recharged using diesel motors connected to generator alternators. This limits their autonomy underwater given that it will be depend on the amount of energy that can be stored in the batteries; currently, a normal value is to have energy to navigate for three days at low speed. As of from the WWII, several shipyards began to carry out research on propulsion systems for submarines that would be capable of operating under anaerobic conditions, independent of the air (AIP Systems). Since then, several proposals have been considered, but there is one option that several navies are currently putting their trust in: fuel cells. The objective of this Project is to stress the different configurations that can be considered to this end, as regards the transportation of hydrogen and oxygen. From the hydrogen point of view, the possibilities of transporting it in metal hydrides or its on-board production through the reforming of different fuels (gas-oil, ethanol, methanol), are analyzed. This study also compares auxiliary systems (including CO2 removers), and proposes solutions, some of which are under development, indicating which are currently being considered to a greater extent. (author)

Sol-gel process preparation and evaluation of the analytical performances of an hydrazine specific chemical sensor

International Nuclear Information System (INIS)

Gojon, C.

1996-12-01

The realisation of optical fibers active chemical collector to analyze hydrazine in line, in the spent fuel reprocessing process is the subject of this work. The p.dimethyl-amino-benzaldehyde has been chosen as reagent for its chemical and optical properties

Optimum cycle frequencies in hand-rim wheelchair propulsion. Wheelchair propulsion technique

NARCIS (Netherlands)

van der Woude, L H; Veeger, DirkJan (H. E. J.); Rozendal, R H; Sargeant, A J

1989-01-01

To study the effect of different cycle frequencies on cardio-respiratory responses and propulsion technique in hand-rim wheelchair propulsion, experienced wheelchair sportsmen (WS group; n = 6) and non-wheelchair users (NW group; n = 6) performed wheelchair exercise tests on a motor-driven

Effect of workload setting on propulsion technique in handrim wheelchair propulsion

NARCIS (Netherlands)

van Drongelen, Stefan; Arnet, Ursina; Veeger, DirkJan (H E. J); van der Woude, Lucas H. V.

Objective: To investigate the influence of workload setting (speed at constant power, method to impose power) on the propulsion technique (i.e. force and timing characteristics) in handrim wheelchair propulsion. Method: Twelve able-bodied men participated in this study. External forces were measured

Laser Propulsion - Quo Vadis

International Nuclear Information System (INIS)

Bohn, Willy L.

2008-01-01

First, an introductory overview of the different types of laser propulsion techniques will be given and illustrated by some historical examples. Second, laser devices available for basic experiments will be reviewed ranging from low power lasers sources to inertial confinement laser facilities. Subsequently, a status of work will show the impasse in which the laser propulsion community is currently engaged. Revisiting the basic relations leads to new avenues in ablative and direct laser propulsion for ground based and space based applications. Hereby, special attention will be devoted to the impact of emerging ultra-short pulse lasers on the coupling coefficient and specific impulse. In particular, laser sources and laser propulsion techniques will be tested in microgravity environment. A novel approach to debris removal will be discussed with respect to the Satellite Laser Ranging (SRL) facilities. Finally, some non technical issues will be raised aimed at the future prospects of laser propulsion in the international community

Critical Propulsion Components. Volume 1; Summary, Introduction, and Propulsion Systems Studies

Science.gov (United States)

2005-01-01

Several studies have concluded that a supersonic aircraft, if environmentally acceptable and economically viable, could successfully compete in the 21st century marketplace. However, before industry can commit to what is estimated as a 15 to 20 billion dollar investment, several barrier issues must be resolved. In an effort to address these barrier issues, NASA and Industry teamed to form the High-Speed Research (HSR) program. As part of this program, the Critical Propulsion Components (CPC) element was created and assigned the task of developing those propulsion component technologies necessary to: (1) reduce cruise emissions by a factor of 10 and (2) meet the ever-increasing airport noise restrictions with an economically viable propulsion system. The CPC-identified critical components were ultra-low emission combustors, low-noise/high-performance exhaust nozzles, low-noise fans, and stable/high-performance inlets. Propulsion cycle studies (coordinated with NASA Langley Research Center sponsored airplane studies) were conducted throughout this CPC program to help evaluate candidate components and select the best concepts for the more complex and larger scale research efforts. The propulsion cycle and components ultimately selected were a mixed-flow turbofan (MFTF) engine employing a lean, premixed, prevaporized (LPP) combustor coupled to a two-dimensional mixed compression inlet and a two-dimensional mixer/ejector nozzle. Due to the large amount of material presented in this report, it was prepared in four volumes; Volume 1: Summary, Introduction, and Propulsion System Studies, Volume 2: Combustor, Volume 3: Exhaust Nozzle, and Volume 4: Inlet and Fan/ Inlet Acoustic Team.

Eigenstates with the auxiliary field method

Energy Technology Data Exchange (ETDEWEB)

Semay, Claude [Service de Physique Nucleaire et Subnucleaire, Universite de Mons-UMONS, 20 Place du Parc, 7000 Mons (Belgium); Silvestre-Brac, Bernard, E-mail: claude.semay@umons.ac.b, E-mail: silvestre@lpsc.in2p3.f [LPSC Universite Joseph Fourier, Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, Avenue des Martyrs 53, F-38026 Grenoble-Cedex (France)

2010-07-02

The auxiliary field method is a powerful technique to obtain approximate closed-form energy formulas for eigenequations in quantum mechanics. Very good results can be obtained for Schroedinger and semirelativistic Hamiltonians with various potentials, even in the case of many-body problems. This method can also provide approximate eigenstates in terms of well-known wavefunctions, for instance harmonic oscillator or hydrogen-like states, but with a characteristic size which depends on quantum numbers. In this paper, we consider two-body Schroedinger equations with linear, logarithmic and exponential potentials and show that analytical approximations of the corresponding eigenstates can be obtained with the auxiliary field method, with very good accuracy in some cases.

Eigenstates with the auxiliary field method

International Nuclear Information System (INIS)

Semay, Claude; Silvestre-Brac, Bernard

2010-01-01

The auxiliary field method is a powerful technique to obtain approximate closed-form energy formulas for eigenequations in quantum mechanics. Very good results can be obtained for Schroedinger and semirelativistic Hamiltonians with various potentials, even in the case of many-body problems. This method can also provide approximate eigenstates in terms of well-known wavefunctions, for instance harmonic oscillator or hydrogen-like states, but with a characteristic size which depends on quantum numbers. In this paper, we consider two-body Schroedinger equations with linear, logarithmic and exponential potentials and show that analytical approximations of the corresponding eigenstates can be obtained with the auxiliary field method, with very good accuracy in some cases.

The Nuclear Cryogenic Propulsion Stage

Science.gov (United States)

Houts, Michael G.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Broadway, Jeramie W.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Borowski, Stanley K.; Scott, John

2014-01-01

The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP). Nuclear propulsion can be affordable and viable compared to other propulsion systems and must overcome a biased public fear due to hyper-environmentalism and a false perception of radiation and explosion risk.

S-matrix for the theories that admit closure of the algebra with the aid of auxiliary fields. Auxiliary fields in supergravity. [Word identities

Energy Technology Data Exchange (ETDEWEB)

Fradkin, E S; Vasiliev, M A [AN SSSR, Moscow. Fizicheskij Inst.

1978-08-19

A minimal set of auxiliary fields (scalarpseudoscalar and pseudovector) providing the closed algebra in supergravity is constructed. A compact scheme for the generating functional with closed gauge algebra is proposed. The S-matrix and the Ward identities for arbitrary theory that admits the closing of the algebra by introducing auxiliary fields is obtained.

Wigner Transport Simulation of Resonant Tunneling Diodes with Auxiliary Quantum Wells

Science.gov (United States)

Lee, Joon-Ho; Shin, Mincheol; Byun, Seok-Joo; Kim, Wangki

2018-03-01

Resonant-tunneling diodes (RTDs) with auxiliary quantum wells ( e.g., emitter prewell, subwell, and collector postwell) are studied using a Wigner transport equation (WTE) discretized by a thirdorder upwind differential scheme. A flat-band potential profile is used for the WTE simulation. Our calculations revealed functions of the auxiliary wells as follows: The prewell increases the current density ( J) and the peak voltage ( V p ) while decreasing the peak-to-valley current ratio (PVCR), and the postwell decreases J while increasing the PVCR. The subwell affects J and PVCR, but its main effect is to decrease V p . When multiple auxiliary wells are used, each auxiliary well contributes independently to the transport without producing side effects.

Operation auxiliary system (SAO)

International Nuclear Information System (INIS)

Lolich, J.; Santome, D.; Drexler, J.

1990-01-01

This work presents an auxiliary system for nuclear power plants operation (SAO). The development purpose consisted in a computing supervision system to be installed at different sites of a reactor, mainly in the control room. The inclusion of this system to a nuclear power plant minimizes the possibility of human error for the facility operation. (Author) [es

Prototype development and test results of a continuous ambient air monitoring system for hydrazine at the 10 ppb level

Science.gov (United States)

Meneghelli, Barry; Parrish, Clyde; Barile, Ron; Lueck, Dale E.

1995-01-01

A Hydrazine Vapor Area Monitor (HVAM) system is currently being field tested as a detector for the presence of hydrazine in ambient air. The MDA/Polymetron Hydrazine Analyzer has been incorporated within the HVAM system as the core detector. This analyzer is a three-electrode liquid analyzer typically used in boiler feed water applications. The HVAM system incorporates a dual-phase sample collection/transport method which simultaneously pulls ambient air samples containing hydrazine and a very dilute sulfuric acid solution (0.0001 M) down a length of 1/4 inch outside diameter (OD) tubing from a remote site to the analyzer. The hydrazine-laden dilute acid stream is separated from the air and the pH is adjusted by addition of a dilute caustic solution to a pH greater than 10.2 prior to analysis. Both the dilute acid and caustic used by the HVAM are continuously generated during system operation on an "as needed" basis by mixing a metered amount of concentrated acid/base with dilution water. All of the waste water generated by the analyzer is purified for reuse by Barnstead ion-exchange cartridges so that the entire system minimizes the generation of waste materials. The pumping of all liquid streams and mixing of the caustic solution and dilution water with the incoming sample are done by a single pump motor fitted with the appropriate mix of peristaltic pump heads. The signal to noise (S/N) ratio of the analyzer has been enhanced by adding a stirrer in the MDA liquid cell to provide mixing normally generated by the high liquid flow rate designed by the manufacturer. An onboard microprocessor continuously monitors liquid levels, sample vacuum, and liquid leak sensors, as well as handles communications and other system functions (such as shut down should system malfunctions or errors occur). The overall system response of the HVAM can be automatically checked at regular intervals by measuring the analyzer response to a metered amount of calibration standard injected

Electric vehicle propulsion alternatives

Science.gov (United States)

Secunde, R. R.; Schuh, R. M.; Beach, R. F.

1983-01-01

Propulsion technology development for electric vehicles is summarized. Analytical studies, technology evaluation, and the development of technology for motors, controllers, transmissions, and complete propulsion systems are included.

Fuel Effective Photonic Propulsion

Science.gov (United States)

Rajalakshmi, N.; Srivarshini, S.

2017-09-01

With the entry of miniaturization in electronics and ultra-small light-weight materials, energy efficient propulsion techniques for space travel can soon be possible. We need to go for such high speeds so that the generation’s time long interstellar missions can be done in incredibly short time. Also renewable energy like sunlight, nuclear energy can be used for propulsion instead of fuel. These propulsion techniques are being worked on currently. The recently proposed photon propulsion concepts are reviewed, that utilize momentum of photons generated by sunlight or onboard photon generators, such as blackbody radiation or lasers, powered by nuclear or solar power. With the understanding of nuclear photonic propulsion, in this paper, a rough estimate of nuclear fuel required to achieve the escape velocity of Earth is done. An overview of the IKAROS space mission for interplanetary travel by JAXA, that was successful in demonstrating that photonic propulsion works and also generated additional solar power on board, is provided; which can be used as a case study. An extension of this idea for interstellar travel, termed as ‘Star Shot’, aims to send a nanocraft to an exoplanet in the nearest star system, which could be potentially habitable. A brief overview of the idea is presented.

Auxiliary bearing design and rotor dynamics analysis of blower fan for HTR-10

International Nuclear Information System (INIS)

Gao Mingshan; Yang Guojun; Xu Yang; Zhao Lei; Yu Suyuan

2005-01-01

The electromagnetic bearing instead of ordinary mechanical bearing was chosen to support the rotor in the blower fan system with helium of 10 MW high temperature gas-cooled test reactor (HTR-10), and the auxiliary bearing was applied in the HTR-10 as the backup protector. When the electromagnetic bearing doesn't work suddenly for the power broken, the auxiliary bearing is used to support the falling rotor with high rotating speed. The rotor system will be protected by the auxiliary bearing. The design of auxiliary bearing is the ultimate safeguard for the system. This rotor is vertically mounted to hold the blower fan. The rotor's length is about 1.5 m, its weight is about 240 kg and the rotating speed is about 5400 r/min. Auxiliary bearing design and rotor dynamics analysis are very important for the design of blower fan to make success. The research status of the auxiliary bearing was summarized in the paper. A sort of auxiliary bearing scheme was proposed. MSC.Marc was selected to analyze the vibration mode and the natural frequency of the rotor. The scheme design of auxiliary bearing and analysis result of rotor dynamics offer the important theoretical base for the protector design and control system of electromagnetic bearing of the blower fan. (authors)

The Range of Gapping and the Status of Auxiliaries.

Science.gov (United States)

Warner, A. R.

Full verbs and auxiliaries are subject to gapping. In the simplest cases, this construction type involves apparent ellipsis within one or more clausal conjuncts under identity with the finite verb or auxiliary of a preceding conjunct. It has often been suggested that the apparent ellipsis must involve at least a verb. Some researchers see in the…

Auxiliary office chair

OpenAIRE

Pascual Osés, Maite

2007-01-01

The aim of this project is to develop an auxiliary office chair, which favorably will compete with the existing chairs on the market. Evolutions of ergonomical survey in the work environment and on the configuration of offices require new products which fulfill the requirements properly. In order to achieve it a survey about office chairs has been carried out: types, characteristics, ways of usage and products on the market besides a large antropometrical study and ergonomics related to work ...

In-Space Propulsion Technology Program Solar Electric Propulsion Technologies

Science.gov (United States)

Dankanich, John W.

2006-01-01

NASA's In-space Propulsion (ISP) Technology Project is developing new propulsion technologies that can enable or enhance near and mid-term NASA science missions. The Solar Electric Propulsion (SEP) technology area has been investing in NASA s Evolutionary Xenon Thruster (NEXT), the High Voltage Hall Accelerator (HiVHAC), lightweight reliable feed systems, wear testing, and thruster modeling. These investments are specifically targeted to increase planetary science payload capability, expand the envelope of planetary science destinations, and significantly reduce the travel times, risk, and cost of NASA planetary science missions. Status and expected capabilities of the SEP technologies are reviewed in this presentation. The SEP technology area supports numerous mission studies and architecture analyses to determine which investments will give the greatest benefit to science missions. Both the NEXT and HiVHAC thrusters have modified their nominal throttle tables to better utilize diminished solar array power on outbound missions. A new life extension mechanism has been implemented on HiVHAC to increase the throughput capability on low-power systems to meet the needs of cost-capped missions. Lower complexity, more reliable feed system components common to all electric propulsion (EP) systems are being developed. ISP has also leveraged commercial investments to further validate new ion and hall thruster technologies and to potentially lower EP mission costs.

Modeling of Ship Propulsion Performance

DEFF Research Database (Denmark)

Pedersen, Benjamin Pjedsted; Larsen, Jan

2009-01-01

Full scale measurements of the propulsion power, ship speed, wind speed and direction, sea and air temperature, from four different loading conditions has been used to train a neural network for prediction of propulsion power. The network was able to predict the propulsion power with accuracy...

The relationship among the solutions of two auxiliary ordinary differential equations

International Nuclear Information System (INIS)

Liu Xiaoping; Liu Chunping

2009-01-01

In a recent article [Phys. Lett. A 356 (2006) 124], Sirendaoreji extended their auxiliary equation method by introducing a new auxiliary ordinary differential equation (NAODE) and its 14 solutions. Then the author studied some nonlinear evolution equations (NLEEs) and got more exact travelling wave solutions. In this paper, we will show that the 14 solutions of the NAODE are actually the same as the solutions obtained by original auxiliary equation method, and they are only different in the form.

Simplified technique for auxiliary orthotopic liver transplantation using a whole graft

Science.gov (United States)

ROCHA-SANTOS, Vinicius; NACIF, Lucas Souto; PINHEIRO, Rafael Soares; DUCATTI, Liliana; ANDRAUS, Wellington; D'ALBURQUERQUE, Luiz Carneiro

2015-01-01

Background Acute liver failure is associated with a high mortality rate and the main purposes of treatment are to prevent cerebral edema and infections, which often are responsible for patient death. The orthotopic liver transplantation is the gold standard treatment and improves the 1-year survival. Aim To describe an alternative technique to auxiliary liver transplant on acute liver failure. Method Was performed whole auxiliary liver transplantation as an alternative technique for a partial auxiliary liver transplantation using a whole liver graft from a child removing the native right liver performed a right hepatectomy. The patient met the O´Grady´s criteria and the rational to indicate an auxiliary orthotopic liver transplantation was the acute classification without hemodynamic instability or renal failure in a patient with deterioration in consciousness. Results The procedure improved liver function and decreased intracranial hypertension in the postoperative period. Conclusion This technique can overcome some postoperative complications that are associated with partial grafts. As far as is known, this is the first case of auxiliary orthotopic liver transplantation in Brazil. PMID:26176253

Window-mounted auxiliary solar heater

Science.gov (United States)

Anthony, K. G.; Herndon, E. P.

1977-01-01

System uses hot-air collectors, no thermal storage, and fan with thermostat switches. At cost of heating efficiency, unit could be manufactured and sold at price allowing immediate entry to market as auxiliary heating system. Its simplicity allows homeowner installation, and maintenance is minimal.

Wheelchairs propulsion analysis: review

Directory of Open Access Journals (Sweden)

Yoshimasa Sagawa Júnior

Full Text Available OBJECTIVES: To analyze aspects related with wheelchair propulsion. MATERIALS AND METHODS: In order to delineate this review the search for information was carried out within electronics databases, using the following descriptors: "wheelchair propulsion", "wheelchair biomechanics" e "wheelchair users". Full papers published in English and French were included in the study. RESULTS: The wheelchair propulsion is a complex movement that requires the execution of repeated bi manual forces applications during a short time period. In this movement high levels of force must be produced due to the bad mechanical performance of the wheelchair. Could be characterized that wheelchair users are not satisfied with their wheelchair, the places are not adapted to their presence and lack of specific criteria for the adjustment of this equipment. The main points to look at are the seat height in relation to elbow flexion (100-120 degrees with his hand in the propulsion rim and tire pressure. The semicircular mode of technique propulsion seems to be more appropriate; in this pattern the wheelchair user returns his hand under the rim after propulsion. Efforts in wheelchairs are high and the incidence of injuries in wheelchair users is high. CONCLUSION: One can conclude that in spite of researchers’ efforts there are still many divergences between topics and methods of evaluation, what makes difficult to apply the experimental results to the wheelchairs users’ daily life.

Ion Beam Propulsion Study

Science.gov (United States)

2008-01-01

The Ion Beam Propulsion Study was a joint high-level study between the Applied Physics Laboratory operated by NASA and ASRC Aerospace at Kennedy Space Center, Florida, and Berkeley Scientific, Berkeley, California. The results were promising and suggested that work should continue if future funding becomes available. The application of ion thrusters for spacecraft propulsion is limited to quite modest ion sources with similarly modest ion beam parameters because of the mass penalty associated with the ion source and its power supply system. Also, the ion source technology has not been able to provide very high-power ion beams. Small ion beam propulsion systems were used with considerable success. Ion propulsion systems brought into practice use an onboard ion source to form an energetic ion beam, typically Xe+ ions, as the propellant. Such systems were used for steering and correction of telecommunication satellites and as the main thruster for the Deep Space 1 demonstration mission. In recent years, "giant" ion sources were developed for the controlled-fusion research effort worldwide, with beam parameters many orders of magnitude greater than the tiny ones of conventional space thruster application. The advent of such huge ion beam sources and the need for advanced propulsion systems for exploration of the solar system suggest a fresh look at ion beam propulsion, now with the giant fusion sources in mind.

Micro-Electro-Analytical Sensor for Sensitive, Selective and Rapid Monitoring of Hydrazine in the Presence of Ammonia, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Hydrazine, a volatile and flammable colorless liquid, is classified as a carcinogen by the US Environmental Protection Agency. It can cause chromosome aberrations...

Electrocatalytic oxidation of diethylaminoethanethiol and hydrazine at single-walled carbon nanotubes modified with prussian blue nanoparticles

CSIR Research Space (South Africa)

Adekunle, AS

2010-11-01

Full Text Available good electrochemical stability in the analytical solution, showing limit of detection in the micromolar range and catalytic rate constant of 3.71×106 and 7.56×106 cm3 mol-1 s-1 for DEAET and hydrazine respectively. The adsorption properties...

Auxiliary basis expansions for large-scale electronic structure calculations.

Science.gov (United States)

Jung, Yousung; Sodt, Alex; Gill, Peter M W; Head-Gordon, Martin

2005-05-10

One way to reduce the computational cost of electronic structure calculations is to use auxiliary basis expansions to approximate four-center integrals in terms of two- and three-center integrals, usually by using the variationally optimum Coulomb metric to determine the expansion coefficients. However, the long-range decay behavior of the auxiliary basis expansion coefficients has not been characterized. We find that this decay can be surprisingly slow. Numerical experiments on linear alkanes and a toy model both show that the decay can be as slow as 1/r in the distance between the auxiliary function and the fitted charge distribution. The Coulomb metric fitting equations also involve divergent matrix elements for extended systems treated with periodic boundary conditions. An attenuated Coulomb metric that is short-range can eliminate these oddities without substantially degrading calculated relative energies. The sparsity of the fit coefficients is assessed on simple hydrocarbon molecules and shows quite early onset of linear growth in the number of significant coefficients with system size using the attenuated Coulomb metric. Hence it is possible to design linear scaling auxiliary basis methods without additional approximations to treat large systems.

Alternative propulsion for automobiles

CERN Document Server

Stan, Cornel

2017-01-01

The book presents – based on the most recent research and development results worldwide - the perspectives of new propulsion concepts such as electric cars with batteries and fuel cells, and furthermore plug in hybrids with conventional and alternative fuels. The propulsion concepts are evaluated based on specific power, torque characteristic, acceleration behaviour, specific fuel consumption and pollutant emissions. The alternative fuels are discussed in terms of availability, production, technical complexity of the storage on board, costs, safety and infrastructure. The book presents summarized data about vehicles with electric and hybrid propulsion. The propulsion of future cars will be marked by diversity – from compact electric city cars and range extender vehicles for suburban and rural areas up to hybrid or plug in SUV´s, Pick up´s and luxury class automobiles.

Space transportation propulsion USSR launcher technology, 1990

Science.gov (United States)

1991-01-01

Space transportation propulsion U.S.S.R. launcher technology is discussed. The following subject areas are covered: Energia background (launch vehicle summary, Soviet launcher family) and Energia propulsion characteristics (booster propulsion, core propulsion, and growth capability).

Meiotic changes in Vicia faba L. subsequent to treatments of hydrazine hydrate and maleic hydrazide

Directory of Open Access Journals (Sweden)

Shaheen Husain

2013-01-01

Full Text Available Assessing the impact of mutagens for creating variations in crops like faba bean (Vicia faba L. is an important criterion in the contemporary world where food insecurity and malnutrition is alarming at the doors of various nations. Impact of two chemical mutagens viz. hydrazine hydrate (HZ and maleic hydrazide (MH on the two varieties (NDF-1 and HB-405 of Vicia faba were analysed in terms of meiotic behavior and pollen sterility. Since there are not enough data about the effect of these mutagens on the chromosomal behaviors of Vicia faba, this study presents the role of hydrazine hydrate and maleic hydrazide as well as various types of chromosomal aberrations in crop improvement. The lower concentration of mutagens showed less pollen sterility compared to the higher concentrations. Manipulation of plant structural component to induce desirable alternations provides valuable material for the breeders and could be used favorably for increasing mutation rate and obtaining a desirable spectrum of mutation in faba beans based on preliminary studies of cell division.

Reactors for nuclear electric propulsion

Energy Technology Data Exchange (ETDEWEB)

Buden, D.; Angelo, J.A. Jr.

1981-01-01

Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades.

Reactors for nuclear electric propulsion

International Nuclear Information System (INIS)

Buden, D.; Angelo, J.A. Jr.

1981-01-01

Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades

Reactor auxiliary cooling facility and coolant supplying method therefor

International Nuclear Information System (INIS)

Ando, Koji; Kinoshita, Shoichiro.

1996-01-01

A reactor auxiliary cooling facility of the present invention comprises a coolant recycling line for recycling coolants by way of a reactor auxiliary coolant pump and a cooling load, a gravitational surge tank for supplying coolants to the coolant recycling line and a supplemental water supplying line for supplying a supply the supplemental water to the tank. Then, a pressurization-type supply water surge tank is disposed for operating the coolant recycling line upon performing an initial system performance test in parallel with the gravitational surge tank. With such a constitution, the period of time required from the start of the installation of reactor auxiliary cooling facilities to the completion of the system performance test can be shortened at a reduced cost without enlarging the scale of the facility. (T.M.)

Reactor auxiliary cooling facility and coolant supplying method therefor

Energy Technology Data Exchange (ETDEWEB)

Ando, Koji; Kinoshita, Shoichiro

1996-06-07

A reactor auxiliary cooling facility of the present invention comprises a coolant recycling line for recycling coolants by way of a reactor auxiliary coolant pump and a cooling load, a gravitational surge tank for supplying coolants to the coolant recycling line and a supplemental water supplying line for supplying a supply the supplemental water to the tank. Then, a pressurization-type supply water surge tank is disposed for operating the coolant recycling line upon performing an initial system performance test in parallel with the gravitational surge tank. With such a constitution, the period of time required from the start of the installation of reactor auxiliary cooling facilities to the completion of the system performance test can be shortened at a reduced cost without enlarging the scale of the facility. (T.M.)

Effects of hydrazine on the solvothermal synthesis of Cu{sub 2}ZnSnSe{sub 4} and Cu{sub 2}CdSnSe{sub 4} nanocrystals for particle-based deposition of films

Energy Technology Data Exchange (ETDEWEB)

Chiang, Ming-Hung [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan 701 (China); Fu, Yaw-Shyan, E-mail: ysfu@mail.nutn.edu.tw [Department of Greenergy, National University of Tainan, Tainan, Taiwan 700 (China); Shih, Cheng-Hung; Kuo, Chun-Cheng [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan 701 (China); Guo, Tzung-Fang [Department of Photonics, Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, Taiwan 701 (China); Lin, Wen-Tai, E-mail: wtlin@mail.ncku.edu.tw [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan 701 (China)

2013-10-01

The effects of hydrazine on the synthesis of Cu{sub 2}ZnSnSe{sub 4} (CZTSe) and Cu{sub 2}CdSnSe{sub 4} (CCTSe) nanocrystals in an autoclave as a function of temperature and time were explored. On heating at 190 °C for 24-72 h, pure CZTSe and CCTSe nanocrystals could readily grow in the hydrazine-added solution, while in the hydrazine-free solution the intermediate phases such as ZnSe, Cu{sub 2}Se, and Cu{sub 2}SnSe{sub 3}, and Cu{sub 2}SnSe{sub 3} and CdSe associated with the CZTSe and CCTSe nanocrystals grew, respectively. This result reveals that hydrazine can speed up the synthesis of pure CZTSe and CCTSe nanocrystals via a solvothermal process. The mechanisms for the hydrazine-enhanced growth of CZTSe and CCTSe nanocrystals were discussed. The pure CZTSe and CCTSe nanocrystals were subsequently fabricated to the smooth films by spin coating without further annealing in selenium atmosphere. This processing may be beneficial to the fabrication of the absorber layer for solar cells and thermoelectric devices. - Highlights: • Hydrazine enhances the growth of pure Cu{sub 2}ZnSnSe{sub 4} and Cu{sub 2}CdSnSe{sub 4} nanocrystals. • The nanocrystals can be fabricated to films by spin coating without annealing. • This solvothermal processing is promising for the fabrication of thin film devices.

Hydrazine reduction of metal ions to porous submicro-structures of Ag, Pd, Cu, Ni, and Bi

Energy Technology Data Exchange (ETDEWEB)

Wang Yue; Shi Yongfang; Chen Yubiao [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Wu Liming, E-mail: liming_wu@fjirsm.ac.cn [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China)

2012-07-15

Porous submicro-structures of Ag, Pd, Cu, Ni, and Bi with high surface area have been prepared by the reduction of hydrazine in glycerol-ethanol solution at room temperature or 120-180 Degree-Sign C. Phase purity, morphology, and specific surface area have been characterized. The reactions probably undergo three different mechanisms: simple reduction for Ag and Pd, coordination-then-reduction for Cu and Ni, and hydrolysis-then-reduction for Bi. The reductant hydrazine also plays an important role to the formation of the porous submicro-structure. The reaction temperature influences the size of the constituent particles and the overall architecture of the submicro-structure so as to influence the surface area value. The as-prepared porous metals have shown the second largest surface area ever reported, which are smaller than those made by the reduction of NaBH{sub 4}, but larger than those made by hard or soft template methods. - Graphical abstract: Porous submicro-structures of Ag, Pd, Cu, Ni, and Bi with high surface area have been prepared by the reduction of hydrazine in the glycerol-ethanol solution at room temperature or 120-180 Degree-Sign C. The reactions undergo different mechanisms: simple reduction for Ag and Pd, coordination-then-reduction for Cu and Ni, and hydrolysis-then-reduction for Bi. Highlights: Black-Right-Pointing-Pointer Syntheses of porous Ag, Pd, Cu, Ni, and Bi with high surface area. Black-Right-Pointing-Pointer Ag and Pd undergo simple reduction. Black-Right-Pointing-Pointer Cu and Ni undergo coordination-then-reduction. Black-Right-Pointing-Pointer Bi undergoes hydrolysis-then-reduction. Black-Right-Pointing-Pointer The as-prepared metals have shown the second largest surface area ever reported.

Characterization of Anammox Hydrazine Dehydrogenase, a Key N2-producing Enzyme in the Global Nitrogen Cycle.

Science.gov (United States)

Maalcke, Wouter J; Reimann, Joachim; de Vries, Simon; Butt, Julea N; Dietl, Andreas; Kip, Nardy; Mersdorf, Ulrike; Barends, Thomas R M; Jetten, Mike S M; Keltjens, Jan T; Kartal, Boran

2016-08-12

Anaerobic ammonium-oxidizing (anammox) bacteria derive their energy for growth from the oxidation of ammonium with nitrite as the electron acceptor. N2, the end product of this metabolism, is produced from the oxidation of the intermediate, hydrazine (N2H4). Previously, we identified N2-producing hydrazine dehydrogenase (KsHDH) from the anammox organism Kuenenia stuttgartiensis as the gene product of kustc0694 and determined some of its catalytic properties. In the genome of K. stuttgartiensis, kustc0694 is one of 10 paralogs related to octaheme hydroxylamine (NH2OH) oxidoreductase (HAO). Here, we characterized KsHDH as a covalently cross-linked homotrimeric octaheme protein as found for HAO and HAO-related hydroxylamine-oxidizing enzyme kustc1061 from K. stuttgartiensis Interestingly, the HDH trimers formed octamers in solution, each octamer harboring an amazing 192 c-type heme moieties. Whereas HAO and kustc1061 are capable of hydrazine oxidation as well, KsHDH was highly specific for this activity. To understand this specificity, we performed detailed amino acid sequence analyses and investigated the catalytic and spectroscopic (electronic absorbance, EPR) properties of KsHDH in comparison with the well defined HAO and kustc1061. We conclude that HDH specificity is most likely derived from structural changes around the catalytic heme 4 (P460) and of the electron-wiring circuit comprising seven His/His-ligated c-type hemes in each subunit. These nuances make HDH a globally prominent N2-producing enzyme, next to nitrous oxide (N2O) reductase from denitrifying microorganisms. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Goal programming for cyclical auxiliary police scheduling at UiTM Cawangan Perlis

Science.gov (United States)

Mustapar, Wasilatul Effah; Nasir, Diana Sirmayunie Mohd; Nor, Nor Azriani Mohamad; Abas, Sharifah Fhahriyah Syed

2017-11-01

Constructing a good and fair schedule for shift workers poses a great challenge as it requires a lot of time and effort. In this study, goal programming has been applied on scheduling to achieve the hard and soft constraints for a cyclical schedule that would ease the head of auxiliary police at building new schedules. To accomplish this goal, shift types were assigned in order to provide a fair schedule that takes into account the auxiliary police's policies and preferences. The model was run using Lingo software. Three out of four goals set for the study were achieved. In addition, the results considered an equal allocation for every auxiliary police, namely 70% for total duty and 30% for the day. Furthermore, the schedule was able to cyclically generate another 10 sets schedule. More importantly, the model has provided unbiased scheduling of auxiliary policies which led to high satisfaction in auxiliary police management.

THE FUTURE OF SPACECRAFT NUCLEAR PROPULSION

OpenAIRE

Jansen, Frank

2014-01-01

This paper summarizes the advantages of space nuclear power and propulsion systems. It describes the actual status of international power level dependent spacecraft nuclear propulsion missions, especially the high power EU-Russian MEGAHIT study including the Russian Megawatt-Class Nuclear Power Propulsion System, the NASA GRC project and the low and medium power EU DiPoP study. Space nuclear propulsion based mission scenarios of these studies are sketched as well.

Minimal set of auxiliary fields and S-matrix for extended supergravity

Energy Technology Data Exchange (ETDEWEB)

Fradkin, E S; Vasiliev, M A [Physical Lebedev Institute - Moscow

1979-05-19

Minimal set of auxiliary fields for linearized SO(2) supergravity and one-parameter extension of the minimal auxiliary fields in the SO(1) supergravity are constructed. The expression for the S-matrix in SO(2) supergravity are given.

Additive Manufacturing of Aerospace Propulsion Components

Science.gov (United States)

Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

2015-01-01

The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

Development of superconducting ship propulsion system

International Nuclear Information System (INIS)

Sakuraba, Junji; Mori, Hiroyuki; Hata, Fumiaki; Sotooka, Koukichi

1991-01-01

When we plan displacement-type monohull high speed vessels, it is difficult to get the hull form with the wave-making resistance minimum, because the stern shape is restricted by arrangement of propulsive machines and shafts. A small-sized and light-weight propulsive machines will reduce the limit to full form design. Superconducting technology will have capability of realizing the small-sized and light-weight propulsion motor. The superconducting electric propulsion system which is composed of superconducting propulsion motors and generators, seems to be an ideal propulsion system for future vehicles. We have constructed a 480 kW superconducting DC homopolar laboratory test motor for developing this propulsion system. The characteristic of this motor is that it has a superconducting field winding and a segmented armature drum. The superconducting field winding which operates in the persistent current mode, is cooled by a condensation heat exchanger and helium refigerating system built into the cryostat of the superconducting field winding. The operating parameters of this motor agreed well with the design parameters. Using the design concepts of this motor, we have conceptually designed a 150,000-200,000 PS superconducting electric propulsive system for a displacement-type monohull high speed ship. (author)

Software To Secure Distributed Propulsion Simulations

Science.gov (United States)

Blaser, Tammy M.

2003-01-01

Distributed-object computing systems are presented with many security threats, including network eavesdropping, message tampering, and communications middleware masquerading. NASA Glenn Research Center, and its industry partners, has taken an active role in mitigating the security threats associated with developing and operating their proprietary aerospace propulsion simulations. In particular, they are developing a collaborative Common Object Request Broker Architecture (CORBA) Security (CORBASec) test bed to secure their distributed aerospace propulsion simulations. Glenn has been working with its aerospace propulsion industry partners to deploy the Numerical Propulsion System Simulation (NPSS) object-based technology. NPSS is a program focused on reducing the cost and time in developing aerospace propulsion engines

BE, DO, and Modal Auxiliaries of 3-Year-Old African American English Speakers

Science.gov (United States)

Newkirk-Turner, Brandi L.; Oetting, Janna B.; Stockman, Ida J.

2014-01-01

Purpose: This study examined African American English--speaking children's use of BE, DO, and modal auxiliaries. Method: The data were based on language samples obtained from 48 three-year-olds. Analyses examined rates of marking by auxiliary type, auxiliary surface form, succeeding element, and syntactic construction and by a number of child…

Fusion propulsion systems

International Nuclear Information System (INIS)

Haloulakos, V.E.; Bourque, R.F.

1989-01-01

The continuing and expanding national efforts in both the military and commercial sectors for exploration and utilization of space will require launch, assembly in space, and orbital transfer of large payloads. The currently available delivery systems, utilizing various forms of chemical propulsion, do not have the payload capacity to fulfill the planned missions. National planning documents such as Air Force Project Forecast II and the National Commission on Space Report to the President contain numerous missions and payload delivery schedules that are beyond the present capabilities of the available systems, such as the Space Shuttle and the Expendable Launch Vehicles (ELVs). The need, therefore, is very pressing to design, develop, and deploy propulsion systems that offer a quantum level increase in delivered performance. One such potential system is fusion propulsion. This paper summarizes the result of an Air Force Astronautics Laboratory (AFAL) sponsored study of fusion propulsion conducted by the McDonnell Douglas Astronautics Company (MDAC), and its subcontractor General Atomics This study explored the potential of fusion propulsion for Air Force missions. Fusion fuels and existing confinement concepts were evaluated according to elaborate criteria. Two fuels, deuterium-tritium and deuterium-helium 3 (D- 3 He) were considered worthy of further consideration. D- 3 He was selected as the most attractive for this Air Force study. The colliding translating compact torus confinement concept was evaluated in depth and found to possibly possess the low mass and compactness required. Another possible concept is inertial confinement with the propellant surrounding the target. 5 refs., 5 figs., 8 tabs

Cold Gas Micro Propulsion

NARCIS (Netherlands)

Louwerse, M.C.

2009-01-01

This thesis describes the development of a micro propulsion system. The trend of miniaturization of satellites requires small sized propulsion systems. For particular missions it is important to maintain an accurate distance between multiple satellites. Satellites drift apart due to differences in

Hydrazine-based synergistic Ti(III)/N doping of surfactant-templated TiO{sub 2} thin films for enhanced visible light photocatalysis

Energy Technology Data Exchange (ETDEWEB)

Islam, Syed Z.; Rankin, Stephen E., E-mail: srankin@engr.uky.edu

2016-10-01

This study reports the preparation of titanium (Ti{sup 3+}) and nitrogen co-doped cubic ordered mesoporous TiO{sub 2} thin films using N{sub 2}H{sub 4} treatment. The resulting co-doped TiO{sub 2} (Ti{sup 3+}-N-TiO{sub 2}) thin films show significant enhancements in visible light absorption and photocatalytic activity. Cubic ordered mesoporous TiO{sub 2} thin films were prepared via a sol-gel method with Pluronic F127 as the pore template. After brief calcination, the TiO{sub 2} films were dipped into hydrazine hydrate which acts both as a nitrogen source and as a reducing agent, followed by heating at low temperature (90 °C). The hydrazine treatment period was varied from 5 to 20 h to obtain different degrees of reduction and nitrogen doping. X-ray photoelectron spectroscopy (XPS) analyses and UV–vis absorbance spectra of Ti{sup 3+}-N-TiO{sub 2} films indicate that the incorporated N atoms and Ti{sup 3+} reduce the band gap of TiO{sub 2} and thus enhance the absorption of visible light. The corresponding visible light photocatalytic activity of Ti{sup 3+}-N-TiO{sub 2} films was determined from the photocatalytic degradation of methylene blue under visible light illumination (at 455 nm). The Ti{sup 3+}-N-TiO{sub 2} films prepared with 10 h of treatment show the optimum photocatalytic activity, with a pseudo-first order rate coefficient of 0.12 h{sup −1}, which is 3 times greater than that of undoped TiO{sub 2} films. Calcination temperature and time were varied prior to hydrazine treatment to confirm that a brief calcination at low temperature (10 min at 350 °C) gave the best photochemical activity. In photoelectrochemical water oxidation using a 455 nm LED, the Ti{sup 3+}-N-TiO{sub 2} films prepared with 10 h of N{sub 2}H{sub 4} treatment show about 4 times the photocurrent compared to undoped TiO{sub 2} films. The present study suggests that hydrazine induced doping is a promising approach to enable synergistic incorporation of N and Ti{sup 3+} into the

Standard and hydrazine water chemistry in primary circuit of VVER 440 units

International Nuclear Information System (INIS)

Burclova, J.

1992-01-01

Standard ammonia-potassium-boron water chemistry of 8 units with VVER 440 in CSFR is discussed as well as the corrosion product activity in the coolant during steady state and shut-down period and surface activity, dose rate build-up and occupational radiation exposure. Available data on hydrazine application (USSR, Hungary) indicate the possibility of the radiation field decreasing. Nevertheless the detailed analysis of 55 cycles of operation under standard water chemistry in Czechoslovakia allows to expect the comparable results for both water chemistries. (author)

“You can get there from here”: Advanced low cost propulsion concepts for small satellites beyond LEO

Science.gov (United States)

Baker, Adam M.; da Silva Curiel, Alex; Schaffner, Jake; Sweeting, Martin

2005-07-01

Small satellites have historically been forced to use low cost propulsion, or to do without in order to maintain low cost. Since 1999 an increasing number of SSTL's customers have demanded the capability to precisely position and subsequently manoeuvre their satellites, driven largely by the current attraction of small satellite constellations such as Disaster Monitoring (DMC), which require propulsion for launcher injection error correction, drag compensation, constellation phasing and proximity manoeuvring and rendezvous. SSTL has successfully flight qualified a simple, low cost propulsion system based on a low power (15-100 W) resistojet employing green propellants such as butane and xenon, and demonstrated key constellation manoeuvres. The system is capable of up to 60 m/s deltaV and will be described here. The SSTL low power resistojet is however limited by a low Isp ( ˜50s for Xenon in the present design, and ˜100s with nitrogen and butane) and a slow reaction time ( 10min warm-up required). An increasing desire to apply small satellite technology to high deltaV missions while retaining the low cost aspect demands new solutions. 'Industry standard' solutions based on cryogenic propulsion, or toxic, carcinogenic storable propellants such as hydrazine/nitrogen oxides combination are not favourable for small satellite missions developed within SSTL's low cost engineering environment. This paper describes a number of strawman missions with high deltaV and/or precision manoeuvring requirements and some low cost propulsion solutions which have been explored at the Surrey Space Centre to meet future needs: Deployment of a complex constellation of nano- or pico-satellites from a secondary launch to a new orbit. The S3TV concept has been developed to allow deployment up to 12 payloads from an 'off-the-shelf' thrust tube, using a restartable nitrous oxide hybrid engine, operating in a dual mode with resistojets for attitude control. Orbit transfer of an enhanced

Operating experiences and degradation detection for auxiliary feedwater systems

International Nuclear Information System (INIS)

Casada, D.; Farmer, W.S.

1992-01-01

A study of Pressurized Water Reactor Auxiliary Feedwater (AFW) Systems has been conducted by Oak Ridge National Laboratory (ORNL) under the auspices of the Nuclear Regulatory Commission's Nuclear Plant Aging Research Program. The results of the study are documented in NUREG/CR-5404, Vol. 1, Auxiliary Feedwater System Aging Study. The study reviewed historical failure experience and current monitoring practices for the AFW System. This paper provides an overview of the study approach and results

Lunar Robotic Precursor Missions Using Electric Propulsion

OpenAIRE

Winski, Richard G.

2006-01-01

A trade study is carried out for the design of electric propulsion based lunar robotic precursor missions. The focus is to understand the relationships between payload mass delivered, electric propulsion power, and trip time. The results are compared against a baseline system using chemical propulsion with LOX/H2. The major differences between the chemical propulsion based and electric propulsion based systems are presented in terms of the payload mass and trip time. It is shown that solar e...

A Review of Laser Ablation Propulsion

International Nuclear Information System (INIS)

Phipps, Claude; Bohn, Willy; Lippert, Thomas; Sasoh, Akihiro; Schall, Wolfgang; Sinko, John

2010-01-01

Laser Ablation Propulsion is a broad field with a wide range of applications. We review the 30-year history of laser ablation propulsion from the transition from earlier pure photon propulsion concepts of Oberth and Saenger through Kantrowitz's original laser ablation propulsion idea to the development of air-breathing 'Lightcraft' and advanced spacecraft propulsion engines. The polymers POM and GAP have played an important role in experiments and liquid ablation fuels show great promise. Some applications use a laser system which is distant from the propelled object, for example, on another spacecraft, the Earth or a planet. Others use a laser that is part of the spacecraft propulsion system on the spacecraft. Propulsion is produced when an intense laser beam strikes a condensed matter surface and produces a vapor or plasma jet. The advantages of this idea are that exhaust velocity of the propulsion engine covers a broader range than is available from chemistry, that it can be varied to meet the instantaneous demands of the particular mission, and that practical realizations give lower mass and greater simplicity for a payload delivery system. We review the underlying theory, buttressed by extensive experimental data. The primary problem in laser space propulsion theory has been the absence of a way to predict thrust and specific impulse over the transition from the vapor to the plasma regimes. We briefly discuss a method for combining two new vapor regime treatments with plasma regime theory, giving a smooth transition from one regime to the other. We conclude with a section on future directions.

Modified Darboux transformations with foreign auxiliary equations

International Nuclear Information System (INIS)

Schulze-Halberg, Axel

2011-01-01

We construct a new type of first-order Darboux transformations for the stationary Schroedinger equation. In contrast to the conventional case, our Darboux transformations support arbitrary (foreign) auxiliary equations. We show that among other applications, our formalism can be used to systematically construct Darboux transformations for Schroedinger equations with energy-dependent potentials, including a recent result (Lin et al., 2007) as a special case. -- Highlights: → We generalize the Darboux transformation for the Schroedinger equation. → By admitting arbitrary auxiliary functions, we provide a new tool for generating solutions. → As a special case we recover a recent result on energy-dependent potentials. → We extend the latter result to very general energy-dependence.

Propulsive efficiency and non- expert swimmers performance

Directory of Open Access Journals (Sweden)

Tiago Barbosa

2009-12-01

Full Text Available Propulsive efficiency is one of the most interesting issues for competitive swimming researchers, has it presents significant relationships with the swimmer’s biophysical behavior and his/her performance. Although propulsive efficiency is a variable that has been quite studied in elite swimmers, there is no research on this issue in young and non-expert swimmers. Thus, the aim of this study was to: (i estimate the propulsive efficiency on non-expert swimmers; (ii identify biomechanical and anthropometrical parameters that are associated with propulsive efficiency; (iii identify the association between the propulsive efficiency and swim performance. Twenty-eight non-expert swimmers participated on this study. It was assessed the propulsive efficiency, biomechanical and anthropometrical parameters, as well as, the swim performance. The propulsive efficiency of non-expert swimmers is lower than data reported in the literature to higher competitive levels swimmers and there are no significant differences between boys and girls. It was also noted that several biomechanical and anthropometrical parameters, as well as, the swim performance are associated with the propulsive efficiency.

Dummy auxiliaries in child and adult second language acquisition of Dutch

NARCIS (Netherlands)

Blom, W.B.T.; de Korte, S.

2011-01-01

In previous research it has been observed that second language (L2) learners of Dutch and German use analytic verbs in contexts where the target language requires synthetic verbs. These analytic verbs consist of a semantically empty auxiliary (dummy auxiliary) that selects a lexical infinitive. In

Extensions of the auxiliary field method to solve Schroedinger equations

International Nuclear Information System (INIS)

Silvestre-Brac, Bernard; Semay, Claude; Buisseret, Fabien

2008-01-01

It has recently been shown that the auxiliary field method is an interesting tool to compute approximate analytical solutions of the Schroedinger equation. This technique can generate the spectrum associated with an arbitrary potential V(r) starting from the analytically known spectrum of a particular potential P(r). In the present work, general important properties of the auxiliary field method are proved, such as scaling laws and independence of the results on the choice of P(r). The method is extended in order to find accurate analytical energy formulae for radial potentials of the form aP(r) + V(r), and several explicit examples are studied. Connections existing between the perturbation theory and the auxiliary field method are also discussed

Extensions of the auxiliary field method to solve Schroedinger equations

Energy Technology Data Exchange (ETDEWEB)

Silvestre-Brac, Bernard [LPSC Universite Joseph Fourier, Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, Avenue des Martyrs 53, F-38026 Grenoble-Cedex (France); Semay, Claude; Buisseret, Fabien [Groupe de Physique Nucleaire Theorique, Universite de Mons-Hainaut, Academie universitaire Wallonie-Bruxelles, Place du Parc 20, B-7000 Mons (Belgium)], E-mail: silvestre@lpsc.in2p3.fr, E-mail: claude.semay@umh.ac.be, E-mail: fabien.buisseret@umh.ac.be

2008-10-24

It has recently been shown that the auxiliary field method is an interesting tool to compute approximate analytical solutions of the Schroedinger equation. This technique can generate the spectrum associated with an arbitrary potential V(r) starting from the analytically known spectrum of a particular potential P(r). In the present work, general important properties of the auxiliary field method are proved, such as scaling laws and independence of the results on the choice of P(r). The method is extended in order to find accurate analytical energy formulae for radial potentials of the form aP(r) + V(r), and several explicit examples are studied. Connections existing between the perturbation theory and the auxiliary field method are also discussed.

Synthesis and Characterization of New Polyamides from 1,2-Bis hydrazine Derivatives

International Nuclear Information System (INIS)

Salaha, A.; Abdel-Bary, E.M.; Kandilea, N.G.

2005-01-01

Preparation of polyamides having different chemical structures allows obtaining new materials with different mechanical and physical properties. The difference in the chemical structure depends mainly on the starting reactants used in condensation polymerization of polyamides. In this paper the synthesis of new polyamides based on the condensation polymerization of 1,2- Bis(3-carboxyacryloyl or carboxybenzoyl) hydrazine derivatives and various diamines has been described. The polymers obtained were characterized using spectroscopic and X-ray analysis. Besides thermal stability and electrical conductivity have been evaluated and correlated with the chemical structure of the polyamides obtained

Spectral properties of ultrasmall CdS nanoparticles Stabilized by mercaptoacids and hydrazine

International Nuclear Information System (INIS)

Solonenko, Dmytro I.; Rayevska, Oleksandra Ye.; Stroyuk, Oleksandr L.; Kuchmiy, Stepan Ya.

2013-01-01

Ultrasmall colloidal CdS quantum dots (QDs) were synthesized in water at room temperature by using a combination of two low-molecular-weight stabilizers - hydrazine and a mercaptoacid, particularly, mercaptoacetic and mercaptopropionic-2 acids. The average size of QDs was found to depend on the Cd-to-S ratio at the synthesis and be as small as 2,5 nm at 80% cadmium(II) excess. The CdS QDs emit broadband photoluminescence in the visible spectrum range with a relative quantum yield of around 5% and the radiative life time of around 100 ns. (authors)

Experimental fast reactor JOYO MK-III functional test. Primary auxiliary cooling system test

International Nuclear Information System (INIS)

Karube, Koji; Akagi, Shinji; Terano, Toshihiro; Onuki, Osamu; Ito, Hideaki; Aoki, Hiroshi; Odo, Toshihiro

2004-03-01

This paper describes the results of primary auxiliary cooling system, which were done as a part of JOYO MK-III function test. The aim of the tests was to confirm the operational performance of primary auxiliary EMP and the protection system including siphon breaker of primary auxiliary cooling system. The items of the tests were: (Test No.): (Test item). 1) SKS-117: EMP start up test. 2) SKS-118-1: EMP start up test when pony motor running. 3) SKS-121: Function test of siphon breaker. The results of the tests satisfied the required performance, and demonstrated successful operation of primary auxiliary cooling system. (author)

Development of Intelligent Auxiliary System for Customized Physical Fitness and Healthcare

Directory of Open Access Journals (Sweden)

Huang Chung-Chi

2016-01-01

Full Text Available With the advent of global high-tech industry and commerce era, the sedentary reduces opportunities of physical activity. And physical fitness and health of people is getting worse and worse. At present, the shortage of physical fitness instructors greatly affected the effectiveness of health promotion. Therefore, it is necessary to develop an auxiliary system which can reduce the workload of instructors and enhance physical fitness and health for people. But current general physical fitness and healthcare system is hard to meet individualized needs. The main purpose of this research is to develop an intelligent auxiliary system for customized physical fitness and healthcare. It records all processes of physical fitness and healthcare system by wireless sensors network. The results of intelligent auxiliary systems for customized physical fitness and healthcare will be generated by fuzzy logic Inference. It will improve individualized physical fitness and healthcare. Finally, we will demonstrate the advantages of the intelligent auxiliary system for customized physical fitness and healthcare.

Synthesis, characterization and anti-bacterial activity of divalent transition metal complexes of hydrazine and trimesic acid

Directory of Open Access Journals (Sweden)

K. Kumar

2018-01-01

Full Text Available Transition metal complexes of trimesic acid and hydrazine mixed-ligands with a general formula M(Htma(N2H42, where, M = Mn, Co, Ni, Cu and Zn; H3tma = trimesic acid, have been prepared and characterized by elemental, structural, spectral and thermal analyses. For the complexes, the carboxylate νasym and νsym stretchings are observed at about 1626 and 1367 cm−1 respectively, with Δν between them of ∼260 cm−1, showing the unidentate coordination of each carboxylate group. The hydrazine moieties are present as bridging bidentates. Electronic and EPR spectral studies suggest an octahedral geometry for the complexes. All these complexes show three steps of decomposition in TGA/DTA. SEM images of CuO and MnO residues obtained from the complexes show nano-sized clusters suggesting that the complexes may be used as precursors for nano-CuO and nano-MnO preparation. The antimicrobial activities of the prepared complexes, against four bacteria have been evaluated.

Aspectual auxiliary verbs in Xitsonga

African Journals Online (AJOL)

Kate H

Let him always come' e. á vá hátl-é vá yá étlélà. OPT 3PL quickly-OPT 3PL go sleep. 'Let them quickly go to bed'. 3.4 Negative markers. Negation is marked on AA verbs. The auxiliary verb hatla 'quickly' is negated in three tenses.

Research Opportunities in Space Propulsion

Science.gov (United States)

Rodgers, Stephen L.

2007-01-01

Rocket propulsion determines the primary characteristics of any space vehicle; how fast and far it can go, its lifetime, and its capabilities. It is the primary factor in safety and reliability and the biggest cost driver. The extremes of heat and pressure produced by propulsion systems push the limits of materials used for manufacturing. Space travel is very unforgiving with little room for errors, and so many things can go wrong with these very complex systems. So we have to plan for failure and that makes it costly. But what is more exciting than the roar of a rocket blasting into space? By its nature the propulsion world is conservative. The stakes are so high at every launch, in terms of payload value or in human life, that to introduce new components to a working, qualified system is extremely difficult and costly. Every launch counts and no risks are tolerated, which leads to the space world's version of Catch-22:"You can't fly till you flown." The last big 'game changer' in propulsion was the use of liquid hydrogen as a fuel. No new breakthrough, low cost access to space system will be developed without new efficient propulsion systems. Because there is no large commercial market driving investment in propulsion, what propulsion research is done is sponsored by government funding agencies. A further difficulty in propulsion technology development is that there are so few new systems flying. There is little opportunity to evolve propulsion technologies and to update existing systems with results coming out of research as there is in, for example, the auto industry. The biggest hurdle to space exploration is getting off the ground. The launch phase will consume most of the energy required for any foreseeable space exploration mission. The fundamental physical energy requirements of escaping earth's gravity make it difficult. It takes 60,000 kJ to put a kilogram into an escape orbit. The vast majority (-97%) of the energy produced by a launch vehicle is used

A Polyethylene Moderator Design for Auxiliary Ex-core Neutron Detector

International Nuclear Information System (INIS)

Lee, Hwan Soo; Shin, Ho Cheol; Bae, Seong Man

2012-01-01

The moderator of detector assembly in ENFMS (Excore Neutron Flux Monitoring System) plays a key role for slowing down from fast neutron to thermal neutron at outside of reactor vessel. Since neutron monitoring detector such as BF3, fission chamber detectors mostly responds to thermal neutron, moderator should be included to neutron detector assembly to detect more efficiently. Generally, resin has been used for moderator of detector in ENFMS of OPR1000 and APR1400, because resin has stable thermal resistance, availability and high neutron moderation characteristics due to the light atomic materials. In case of an auxiliary ex-core neutron detector, the polyethylene is suggested that polyethylene has a better moderator rather than resin, then, the amounts of moderator are reduced. This is important thing for auxiliary ex-core detector equipment at reactor, because the auxiliary equipment should affect minimally to another system. In this study, polyethylene moderator is designed for auxiliary ex-core neutron detector. To find out the optimal thickness of polyethylene moderator, preliminary simulation and experiments are performed. And sensitivity simulation for detector moderator at actual reactor is performed by DORT code

Propulsion System and Orbit Maneuver Integration in CubeSats: Trajectory Control Strategies Using Micro Ion Propulsion

Science.gov (United States)

Hudson, Jennifer; Martinez, Andres; Petro, Andrew

2015-01-01

The Propulsion System and Orbit Maneuver Integration in CubeSats project aims to solve the challenges of integrating a micro electric propulsion system on a CubeSat in order to perform orbital maneuvers and control attitude. This represents a fundamentally new capability for CubeSats, which typically do not contain propulsion systems and cannot maneuver far beyond their initial orbits.

Theoretical and numerical analysis of auxiliary heating for cryogenic target fabrication

International Nuclear Information System (INIS)

Yang Xiaohu; Tian Chenglin; Yin Yan; Xu Han; Zhuo Hongbin

2008-01-01

In order to compensate for the nonspherical-symmetric heat flux in the hohlraum, auxiliary heating is usually applied to the outside wall of the hohlraum during the cooling process. A one-dimensional heat exchange theoretical model has been proposed in the indirect-drive target, to analyze the required auxiliary heat flux. With a two dimensional axisymmetric model, the auxiliary heating mechanism has been simulated by FLUENT code. The optimum heat flux which is 635 W/m 2 has been obtained as the heaters around the outside of the hohlraum about 1.3 mm above and below the mid-plane. The result is in good agreement with the theoretical model. (authors)

Entanglement Capacity of Two-Qubit Unitary Operator with the Help of Auxiliary System

International Nuclear Information System (INIS)

Hu Baolin; Di Yaomin

2007-01-01

The entanglement capacity of general two-qubit unitary operators is studied when auxiliary systems are allowed, and the analytical results based on linear entropy when input states are disentangled are given. From the results the condition for perfect entangler, α 1 = α 2 = π/4, is obtained. Contrary to the case without auxiliary system, the parameter α 3 may play active role to the entanglement capacity when auxiliary systems are allowed.

The Future Mission Tasking and Resourcing of the U.S. Coast Guard Auxiliary

Science.gov (United States)

2012-09-01

the years. Therefore, this study cannot present what the demographic makeup of the Auxiliary was at any past point, and cannot identify if there were...Auxiliary, and the Nation’s projected demographic composition. The demographic makeup of the country, the country’s future volunteers, is changing...command in the spring of 2010.104 This one-page document broad- brushes three prioritized overarching Auxiliary missions: 1) to promote and improve

Mirror fusion propulsion system - A performance comparison with alternate propulsion systems for the manned Mars mission

International Nuclear Information System (INIS)

Deveny, M.; Carpenter, S.; O'connell, T.; Schulze, N.

1993-06-01

The performance characteristics of several propulsion technologies applied to piloted Mars missions are compared. The characteristics that are compared are Initial Mass in Low Earth Orbit (IMLEO), mission flexibility, and flight times. The propulsion systems being compared are both demonstrated and envisioned: Chemical (or Cryogenic), Nuclear Thermal Rocket (NTR) solid core, NTR gas core, Nuclear Electric Propulsion (NEP), and a mirror fusion space propulsion system. The proposed magnetic mirror fusion reactor, known as the Mirror Fusion Propulsion System (MFPS), is described. The description is an overview of a design study that was conducted to convert a mirror reactor experiment at Lawrence Livermore National Lab (LLNL) into a viable space propulsion system. Design principles geared towards minimizing mass and maximizing power available for thrust are identified and applied to the LLNL reactor design, resulting in the MFPS. The MFPS' design evolution, reactor and fuel choices, and system configuration are described. Results of the performance comparison shows that the MFPS minimizes flight time to 60 to 90 days for flights to Mars while allowing continuous return-home capability while at Mars. Total MFPS IMLEO including propellant and payloads is kept to about 1,000 metric tons. 50 refs

Surface modification of g-C3N4 by hydrazine: Simple way for noble-metal free hydrogen evolution catalysts

KAUST Repository

Chen, Yin

2015-11-02

The graphitic carbon nitride (g-C3N4) usually is thought to be an inert material and it’s difficult to have the surface terminated NH2 groups functionalized. By modifying the g-C3N4 surface with hydrazine, the diazanyl group was successfully introduced onto the g-C3N4 surface, which allows the introduction with many other function groups. Here we illustrated that by reaction of surface hydrazine group modified g-C3N4 with CS2 under basic condition, a water electrolysis active group C(=S)SNi can be implanted on the g-C3N4 surface, and leads to a noble metal free hydrogen evolution catalyst. This catalyst has 40% hydrogen evolution efficiency compare to the 3 wt% Pt photo precipitated g-C3N4, with only less than 0.2 wt% nickel.

Surface modification of g-C3N4 by hydrazine: Simple way for noble-metal free hydrogen evolution catalysts

KAUST Repository

Chen, Yin; Lin, Bin; Wang, Hong; Yang, Yong; Zhu, Haibo; Yu, Weili; Basset, Jean-Marie

2015-01-01

The graphitic carbon nitride (g-C3N4) usually is thought to be an inert material and it’s difficult to have the surface terminated NH2 groups functionalized. By modifying the g-C3N4 surface with hydrazine, the diazanyl group was successfully introduced onto the g-C3N4 surface, which allows the introduction with many other function groups. Here we illustrated that by reaction of surface hydrazine group modified g-C3N4 with CS2 under basic condition, a water electrolysis active group C(=S)SNi can be implanted on the g-C3N4 surface, and leads to a noble metal free hydrogen evolution catalyst. This catalyst has 40% hydrogen evolution efficiency compare to the 3 wt% Pt photo precipitated g-C3N4, with only less than 0.2 wt% nickel.

Environmental practices of the auxiliary companies to the Spanish automobile industry

Science.gov (United States)

González-Torre, Pilar L.; González, Beatriz A.; Gupta, Surendra M.

2005-11-01

The automobile manufacturing industry plays a very important role in a country's economy. The importance of automobile manufacturing industry lies in its sheer size and complexity in terms of the direct and indirect influence it commands across many other industries. While millions of people are employed in the automobile manufacturing industry, it is estimated that more than two and half times that number are employed in the auxiliary companies that supply parts to the automobile manufacturing companies. The auxiliary companies represent a group of businesses of various sizes, types, and geographical locations, producing a vast variety of products ranging from the very simple to the extremely intricate. In this study, the current environmental practices of management in the core Spanish auxiliary companies that do business with the automobile manufacturing industry (and thus form a large part of the automobile manufacturing industry's supply chain) are investigated. We show that while automobile manufacturing companies are under scrutiny to become more and more environmentally friendly, not only at their manufacturing stage but also at their products' useful and EOL stages, there appears to be no such burden on the auxiliary companies. Our conclusion is based on an elaborate survey conducted during the fall of 2004 of Spanish auxiliary companies with questions about the characteristics, environmental practices and reverse logistics related activities carried out by the companies.

Curricular Guidelines for Dental Auxiliary Radiology.

Science.gov (United States)

Journal of Dental Education, 1981

1981-01-01

AADS curricular guidelines suggest objectives for these areas of dental auxiliary radiology: physical principles of X-radiation in dentistry, related radiobiological concepts, principles of radiologic health, radiographic technique, x-ray films and intensifying screens, factors contributing to film quality, darkroom, and normal variations in…

Linearized curvatures for auxiliary fields in the de Sitter space

Energy Technology Data Exchange (ETDEWEB)

Vasiliev, M A

1988-09-19

New consistent linearized curvatures in the de Sitter space are constructed. The sequence of actions, describing bosonic and fermionic gauge auxiliary fields, is found based on these curvatures. The proposed actions are parametrized by two integer parameters, n greater than or equal to 0 and m greater than or equal to 0. The simplest case n=m=0 corresponds in the flat limit to the auxiliary fields of 'new minimal' supergravity. The hamiltonian formulation is developed for the auxiliary fields suggested; hamiltonians and first- and second-class constraints are constructed. Using these results, it is shown that the systems of fields proposed possess no dynamical degrees of freedom in de Sitter and flat spaces. In addition the hamiltonian formalism is analysed for some free dynamical systems based on linearized higher-spin curvatures introduced previously.

Improvement of stability of sinusoidally driven atmospheric pressure plasma jet using auxiliary bias voltage

Directory of Open Access Journals (Sweden)

Hyun-Jin Kim

2015-12-01

Full Text Available In this study, we have proposed the auxiliary bias pulse scheme to improve the stability of atmospheric pressure plasma jets driven by an AC sinusoidal waveform excitation source. The stability of discharges can be significantly improved by the compensation of irregular variation in memory voltage due to the effect of auxiliary bias pulse. From the parametric study, such as the width, voltage, and onset time of auxiliary bias pulse, it has been demonstrated that the auxiliary bias pulse plays a significant role in suppressing the irregular discharges caused by the irregular variation in memory voltage and stable discharge can be initiated with the termination of the auxiliary bias pulse. As a result of further investigating the effects of the auxiliary pulse scheme on the jet stability under various process conditions such as the distance between the jet head and the counter electrode, and carrier gas flow, the jet stability can be improved by adjusting the amplitude and number of the bias pulse depending on the variations in the process conditions.

Distributed propulsion.

OpenAIRE

Lindström, Robin; Rosvall, Tobias

2013-01-01

En prestandaanalys utfördes på en SAAB 2000 som referensobjekt. Olika metoder för att driva flygplan på ett miljövänligare sätt utvärderades tillsammans med distributed propulsion. Efter undersökningar valdes elmotorer tillsammans med Zink-luft batterier för att driva SAAB 2000 med distributed propulsion. En prestandaanalys utfördes på detta plan på samma sätt som för den ursprungliga SAAB 2000. Resultaten jämfördes och slutsatsen blev att räckvidden var för kort för att konfigurationen skull...

Vehicle with inclinable caterpillar propulsion units

International Nuclear Information System (INIS)

Clar, G.

1991-01-01

This vehicle usable in hostile environment such nuclear industry has four propulsion units with a caterpillar track and two integrated motors: one for advancing the caterpillar track and the other for inclining the propulsion unit when overcoming obstacles. Each propulsion unit is easily replaceable because there are no mechanical parts in the body of the vehicle [fr

Auxiliary/Master microprocessor CAMAC Crate Controller applications

International Nuclear Information System (INIS)

Barsotti, E.

1975-01-01

The need for further sophistication of an already complex serial CAMAC control system at Fermilab led to the development of an Auxilary/Master CAMAC Crate Controller. The controller contains a Motorola 6800 microprocessor, 2K bytes of RAM, and 8K bytes of PROM memory. Bussed dataway lines are time shared with CAMAC signals to provide memory expansion and direct addressing of peripheral devices without the need of external cabling. The Auxiliary/Master Crate Controller (A/MCC) can function as either a Master, i.e., stand alone, crate controller or as an Auxiliary controller to Fermilab's Serial Crate Controller (SCC). Two modules, one single- and one double-width, make up an A/MCC. The microprocessor has one nonmaskable and one maskable vectored interrupt. Time sharing the dataway between SCC programmed and block transfer generated dataway cycles and A/MCC operations still allows a 99 percent microprocessor CPU busy time. Since the conception of the A/MCC, there has been an increasing number of control system-related projects proposed which would not have been possible or would have been very difficult to implement without such a device. The first such application now in use at Fermilab is a stand-alone control system for a mass spectrometer experiment in the Main Ring Internal Target Area. This application in addition to other proposed A/MCC applications, both stand-alone and auxiliary, is discussed

Improving Semi-Supervised Learning with Auxiliary Deep Generative Models

DEFF Research Database (Denmark)

Maaløe, Lars; Sønderby, Casper Kaae; Sønderby, Søren Kaae

Deep generative models based upon continuous variational distributions parameterized by deep networks give state-of-the-art performance. In this paper we propose a framework for extending the latent representation with extra auxiliary variables in order to make the variational distribution more...... expressive for semi-supervised learning. By utilizing the stochasticity of the auxiliary variable we demonstrate how to train discriminative classifiers resulting in state-of-the-art performance within semi-supervised learning exemplified by an 0.96% error on MNIST using 100 labeled data points. Furthermore...

分子动力学模拟压水反应堆中联氨对水的影响%Molecular dynamics simulation for the impact of hydrazine on the water of pressurized water reactors

Institute of Scientific and Technical Information of China (English)

范永胜; 陈旭; 周维; 史顺平; 李勇

2011-01-01

本文采用分子动力学方法模拟在常温常压下(1 atm,298 K)和在压水堆环境下(155 atm,626 K),水分子数为256,联氨(N2H4)分子数为0,25,50,75等不同数目时,水和联氨粒子系统的动力性质和微观结构.同时探讨了联氨分子的引入对水中溶解氧的影响.从模拟结果可知,在常温常压下,当联氨的分子数为0,25,50,75时,粒子系统的均方位移会随联氨分子数的增加而增加;联氨分子数为0与为25,50,75比较时会少一个数量级;压水堆环境下,联氨分子数为50时的均方位移比常温常压下高出约4倍,但粒子系统的均方位移不随联氨的分子数增加而增加;联氨分子数为50时的均方位移高于分子数为25和75时的均方位移.此外,粒子系统的微观结构,从径向分布函数看,在常温常压下也会随着联氨分子浓度的增加而增加,这与联氨容易和水反应生成水合联氨的实际情况相符,而在压水堆环境下,联氨分子数为25,50与为0的水比较,径向分布均不会有大的变化,而分子数为75时会出现明显的增加.模拟数据表明,加入压水堆中的联氨对水中的溶解氧有明显的抑制作用,但并不是联氨的浓度越浓抑制作用就越强.对这种现象及其原因进行了较为全面的揭示.%In this paper, we used molecular dynamics to simulate dynamic properties and micro-structure of the water-hydrazine particle system under various conditions: chamber condition of 1 atm, 298 K; pressurized water reactor (PWR)environment of 155 atm, 626 K; with number of water molecules of 256, numbers of hydrazine ( N2H4) molecules of 0,25, 50 and 75. And we have also explored the impact on the dissolved oxygen in water when hydrazine molecule is added to the system. The simulation results show that in the chamber ambient, when the number of molecules of hydrazine varies from 0 to 25, 50 and 75, the mean square displacement (MSD) in the particle system will increase with the number of

Modal Auxiliaries and Their Semantic Functions Used by Advanced EFL Learners

Science.gov (United States)

Torabiardakani, Najmeh; Khojasteh, Laleh; Shokrpour, Nasrin

2015-01-01

Since modal auxiliary verbs have been proved to be one of the most troublesome grammatical structures in English, the researchers of this study decided to do an analysis on the ways in which advanced EFL Iranian students use modal auxiliaries focusing specially on nine modals' semantic functions. Consequently, was conducted based on the following…

Distributed propulsion and future aerospace technologies

OpenAIRE

Ameyugo, Gregorio

2007-01-01

This thesis describes an Engineering Doctorate project in Distributed Propulsion carried out from 2004 to 2007 at Cranfield University. Distributed propulsion is a propulsion system arrangement that consists in spreading the engine thrust along the aircraft span. This can be accomplished by distributing a series of driven fans or the engines themselves. The aim of this project is to determine the feasibility of ...

Development of KALIMER auxiliary sodium and cover gas management system

International Nuclear Information System (INIS)

Kwon, Sang Woon; Hwang, Sung Tae

1996-11-01

The objectives of this report are to develop and to describe the auxiliary liquid metal and cover gas management systems of KALIMER. the system includes following system: (1) Auxiliary liquid metal system (2) Inert gas receiving and processing system (3) Impurity monitoring and analysis system. Auxiliary liquid metal and cover gas management system of KALIMER was developed. Functions of each systems and design basis were describes. The auxiliary liquid metal system receives, transfers, and purifies all sodium used in the plant. The system furnishes the required sodium quantity at the pressure, temperature, flow rate, and purity specified by the interfacing system. The intermediated sodium processing subsystem (ISPS) provides continuous purification of IHTS sodium, as well as performs the initial fill operation for both the IHTS and reactor vessel. The primary sodium processing subsystem provides purification (cold trapping) for sodium used in the reactor vessel. The inert gas receiving and processing (IGRP) system provides liquefied and ambient gas storage, delivers inert gases of specified composition and purity at regulated flow rates and pressures to points of usage throughout the KALIMER, and accepts the contaminated gases through its vacuum facilities for storage and transfer to the gas radwaste system. Three gases are used in the KALIMER: helium, argon, and nitrogen. 11 tabs., 12 figs. (Author)

Development of KALIMER auxiliary sodium and cover gas management system

Energy Technology Data Exchange (ETDEWEB)

Kwon, Sang Woon; Hwang, Sung Tae [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1996-11-01

The objectives of this report are to develop and to describe the auxiliary liquid metal and cover gas management systems of KALIMER. the system includes following system: (1) Auxiliary liquid metal system (2) Inert gas receiving and processing system (3) Impurity monitoring and analysis system. Auxiliary liquid metal and cover gas management system of KALIMER was developed. Functions of each systems and design basis were describes. The auxiliary liquid metal system receives, transfers, and purifies all sodium used in the plant. The system furnishes the required sodium quantity at the pressure, temperature, flow rate, and purity specified by the interfacing system. The intermediated sodium processing subsystem (ISPS) provides continuous purification of IHTS sodium, as well as performs the initial fill operation for both the IHTS and reactor vessel. The primary sodium processing subsystem provides purification (cold trapping) for sodium used in the reactor vessel. The inert gas receiving and processing (IGRP) system provides liquefied and ambient gas storage, delivers inert gases of specified composition and purity at regulated flow rates and pressures to points of usage throughout the KALIMER, and accepts the contaminated gases through its vacuum facilities for storage and transfer to the gas radwaste system. Three gases are used in the KALIMER: helium, argon, and nitrogen. 11 tabs., 12 figs. (Author).

Systems Analysis Initiated for All-Electric Aircraft Propulsion

Science.gov (United States)

Kohout, Lisa L.

2003-01-01

A multidisciplinary effort is underway at the NASA Glenn Research Center to develop concepts for revolutionary, nontraditional fuel cell power and propulsion systems for aircraft applications. There is a growing interest in the use of fuel cells as a power source for electric propulsion as well as an auxiliary power unit to substantially reduce or eliminate environmentally harmful emissions. A systems analysis effort was initiated to assess potential concepts in an effort to identify those configurations with the highest payoff potential. Among the technologies under consideration are advanced proton exchange membrane (PEM) and solid oxide fuel cells, alternative fuels and fuel processing, and fuel storage. Prior to this effort, the majority of fuel cell analysis done at Glenn was done for space applications. Because of this, a new suite of models was developed. These models include the hydrogen-air PEM fuel cell; internal reforming solid oxide fuel cell; balance-of-plant components (compressor, humidifier, separator, and heat exchangers); compressed gas, cryogenic, and liquid fuel storage tanks; and gas turbine/generator models for hybrid system applications. Initial mass, volume, and performance estimates of a variety of PEM systems operating on hydrogen and reformate have been completed for a baseline general aviation aircraft. Solid oxide/turbine hybrid systems are being analyzed. In conjunction with the analysis efforts, a joint effort has been initiated with Glenn s Computer Services Division to integrate fuel cell stack and component models with the visualization environment that supports the GRUVE lab, Glenn s virtual reality facility. The objective of this work is to provide an environment to assist engineers in the integration of fuel cell propulsion systems into aircraft and provide a better understanding of the interaction between system components and the resulting effect on the overall design and performance of the aircraft. Initially, three

Enabling Electric Propulsion for Flight

Science.gov (United States)

Ginn, Starr Renee

2015-01-01

Team Seedling project AFRC and LaRC 31ft distributed electric propulsion wing on truck bed up 75 miles per hour for coefficient of lift validation. Convergent Aeronautic Solutions project, sub-project Convergent Electric Propulsion Technologies AFRC, LaRC and GRC, re-winging a 4 passenger Tecnam aircraft with a 31ft distributed electric propulsion wing. Advanced Air Transport Technologies (Fixed Wing), Hybrid Electric Research Theme, developing a series hybrid ironbird and flight sim to study integration and performance challenges in preparation for a 1-2 MW flight project.

Ionic Liquids to Replace Hydrazine

Science.gov (United States)

Koelfgen, Syri; Sims, Joe; Forton, Melissa; Allan, Barry; Rogers, Robin; Shamshina, Julia

2011-01-01

A method for developing safe, easy-to-handle propellants has been developed based upon ionic liquids (ILs) or their eutectic mixtures. An IL is a binary combination of a typically organic cation and anion, which generally produces an ionic salt with a melting point below 100 deg C. Many ILs have melting points near, or even below, room temperature (room temperature ionic liquids, RTILs). More importantly, a number of ILs have a positive enthalpy of formation. This means the thermal energy released during decomposition reactions makes energetic ILs ideal for use as propellants. In this specific work, to date, a baseline set of energetic ILs has been identified, synthesized, and characterized. Many of the ILs in this set have excellent performance potential in their own right. In all, ten ILs were characterized for their enthalpy of formation, density, melting point, glass transition point (if applicable), and decomposition temperature. Enthalpy of formation was measured using a microcalorimeter designed specifically to test milligram amounts of energetic materials. Of the ten ILs characterized, five offer higher Isp performance than hydrazine, ranging between 10 and 113 seconds higher than the state-of-the-art propellant. To achieve this level of performance, the energetic cations 4- amino-l,2,4-triazolium and 3-amino-1,2,4-triazolium were paired with various anions in the nitrate, dicyanamide, chloride, and 3-nitro-l,2,4-triazole families. Protonation, alkylation, and butylation synthesis routes were used for creation of the different salts.

Aeroelastic Wing Shaping Using Distributed Propulsion

Science.gov (United States)

Nguyen, Nhan T. (Inventor); Reynolds, Kevin Wayne (Inventor); Ting, Eric B. (Inventor)

2017-01-01

An aircraft has wings configured to twist during flight. Inboard and outboard propulsion devices, such as turbofans or other propulsors, are connected to each wing, and are spaced along the wing span. A flight controller independently controls thrust of the inboard and outboard propulsion devices to significantly change flight dynamics, including changing thrust of outboard propulsion devices to twist the wing, and to differentially apply thrust on each wing to change yaw and other aspects of the aircraft during various stages of a flight mission. One or more generators can be positioned upon the wing to provide power for propulsion devices on the same wing, and on an opposite wing.

Visions of the Future: Hybrid Electric Aircraft Propulsion

Science.gov (United States)

Bowman, Cheryl L.

2016-01-01

The National Aeronautics and Space Administration (NASA) is investing continually in improving civil aviation. Hybridization of aircraft propulsion is one aspect of a technology suite which will transform future aircraft. In this context, hybrid propulsion is considered a combination of traditional gas turbine propulsion and electric drive enabled propulsion. This technology suite includes elements of propulsion and airframe integration, parallel hybrid shaft power, turbo-electric generation, electric drive systems, component development, materials development and system integration at multiple levels.

Hydraulic turbines and auxiliary equipment

Energy Technology Data Exchange (ETDEWEB)

Luo Gaorong [Organization of the United Nations, Beijing (China). International Centre of Small Hydroelectric Power Plants

1995-07-01

This document presents a general overview on hydraulic turbines and auxiliary equipment, emphasizing the turbine classification, in accordance with the different types of turbines, standard turbine series in China, turbine selection based on the basic data required for the preliminary design, general hill model curves, chart of turbine series and the arrangement of application for hydraulic turbines, hydraulic turbine testing, and speed regulating device.

MW-Class Electric Propulsion System Designs

Science.gov (United States)

LaPointe, Michael R.; Oleson, Steven; Pencil, Eric; Mercer, Carolyn; Distefano, Salvador

2011-01-01

Electric propulsion systems are well developed and have been in commercial use for several years. Ion and Hall thrusters have propelled robotic spacecraft to encounters with asteroids, the Moon, and minor planetary bodies within the solar system, while higher power systems are being considered to support even more demanding future space science and exploration missions. Such missions may include orbit raising and station-keeping for large platforms, robotic and human missions to near earth asteroids, cargo transport for sustained lunar or Mars exploration, and at very high-power, fast piloted missions to Mars and the outer planets. The Advanced In-Space Propulsion Project, High Efficiency Space Power Systems Project, and High Power Electric Propulsion Demonstration Project were established within the NASA Exploration Technology Development and Demonstration Program to develop and advance the fundamental technologies required for these long-range, future exploration missions. Under the auspices of the High Efficiency Space Power Systems Project, and supported by the Advanced In-Space Propulsion and High Power Electric Propulsion Projects, the COMPASS design team at the NASA Glenn Research Center performed multiple parametric design analyses to determine solar and nuclear electric power technology requirements for representative 300-kW class and pulsed and steady-state MW-class electric propulsion systems. This paper describes the results of the MW-class electric power and propulsion design analysis. Starting with the representative MW-class vehicle configurations, and using design reference missions bounded by launch dates, several power system technology improvements were introduced into the parametric COMPASS simulations to determine the potential system level benefits such technologies might provide. Those technologies providing quantitative system level benefits were then assessed for technical feasibility, cost, and time to develop. Key assumptions and primary

Preparation and characterization of AuNPs/CNTs-ErGO electrochemical sensors for highly sensitive detection of hydrazine.

Science.gov (United States)

Zhao, Zhenting; Sun, Yongjiao; Li, Pengwei; Zhang, Wendong; Lian, Kun; Hu, Jie; Chen, Yong

2016-09-01

A highly sensitive electrochemical sensor of hydrazine has been fabricated by Au nanoparticles (AuNPs) coating of carbon nanotubes-electrochemical reduced graphene oxide composite film (CNTs-ErGO) on glassy carbon electrode (GCE). Cyclic voltammetry and potential amperometry have been used to investigate the electrochemical properties of the fabricated sensors for hydrazine detection. The performances of the sensors were optimized by varying the CNTs to ErGO ratio and the quantity of Au nanoparticles. The results show that under optimal conditions, a sensitivity of 9.73μAμM(-1)cm(-2), a short response time of 3s, and a low detection limit of 0.065μM could be achieved with a linear concentration response range from 0.3μM to 319μM. The enhanced electrochemical performances could be attributed to the synergistic effect between AuNPs and CNTs-ErGO film and the outstanding catalytic effect of the Au nanoparticles. Finally, the sensor was successfully used to analyse the tap water, showing high potential for practical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

The Space Nuclear Thermal Propulsion Program: Propulsion for the twenty first century

International Nuclear Information System (INIS)

Bleeker, G.; Moody, J.; Kesaree, M.

1993-01-01

As mission requirements approach the limits of the chemical propulsion systems, new engines must be investigated that can meet the advanced mission requirements of higher payload fractions, higher velocities, and consequently higher specific Impulses (Isp). The propulsion system that can meet these high demands is a nuclear thermal rocket engine. This engine generates the thrust by expanding/existing the hydrogen, heated from the energy derived from the fission process in a reactor, through a nozzle. The Department of Defense (DoD), however, initiated a new nuclear rocket development program in 1987 for ballistic missile defense application. The Space Nuclear Thermal Propulsion (SNTP) Program that seeks to improve on the technology of ROVER/NERVA grew out of this beginning and has been managed by the Air Force, with the involvement of DoE and NASA. The goal of the SNTP Program is to develop an engine to meet potential Air Force requirements for upper stage engine, bimodal propulsion/power applications, and orbital transfer vehicles, as well as the NASA requirements for possible missions to the Moon and Mars. During the entire life of the program, the DoD has considered safety to be of paramount importance, and is following all national environmental policies

Powered Flight The Engineering of Aerospace Propulsion

CERN Document Server

Greatrix, David R

2012-01-01

Whilst most contemporary books in the aerospace propulsion field are dedicated primarily to gas turbine engines, there is often little or no coverage of other propulsion systems and devices such as propeller and helicopter rotors or detailed attention to rocket engines. By taking a wider viewpoint, Powered Flight - The Engineering of Aerospace Propulsion aims to provide a broader context, allowing observations and comparisons to be made across systems that are overlooked by focusing on a single aspect alone. The physics and history of aerospace propulsion are built on step-by-step, coupled with the development of an appreciation for the mathematics involved in the science and engineering of propulsion. Combining the author’s experience as a researcher, an industry professional and a lecturer in graduate and undergraduate aerospace engineering, Powered Flight - The Engineering of Aerospace Propulsion covers its subject matter both theoretically and with an awareness of the practicalities of the industry. To ...

Progress on radio frequency auxiliary heating system designs in ITER

International Nuclear Information System (INIS)

Makowski, M.; Bosia, G.; Elio, F.

1996-09-01

ITER will require over 100 MW of auxiliary power for heating, on- and off-axis current drive, accessing the H-mode, and plasma shut-down. The Electron Cyclotron Range of Frequencies (ECRF) and Ion Cyclotron Range of Frequencies (ICRF) are two forms of Radio Frequency (RF) auxiliary power being developed for these applications. Design concepts for both the ECRF and ICRF systems are presented, key features and critical design issues are discussed, and projected performances outlined

An auxiliary differential equation FDTD method for anisotropic magnetized plasmas

International Nuclear Information System (INIS)

Liu Shaobin; Mo Jinjun; Yuan Naichang

2004-01-01

An auxiliary differential equation finite-difference time-domain (ADE-FDTD) methodology for anisotropic magnetized plasmas is derived. The method is based on a difference approximation of the auxiliary differential equation. A comparison with the JEC method is included. The CPU time saving by several times and accuracy of the method are confirmed by computing the reflection and transmission through a magnetized plasma layer with the direction of propagation parallel to the direction of the biasing field

Electrospinning of aligned fibers with adjustable orientation using auxiliary electrodes

International Nuclear Information System (INIS)

Arras, Matthias M L; Grasl, Christian; Schima, Heinrich; Bergmeister, Helga

2012-01-01

A conventional electrospinning setup was upgraded by two turnable plate-like auxiliary high-voltage electrodes that allowed aligned fiber deposition in adjustable directions. Fiber morphology was analyzed by scanning electron microscopy and attenuated total reflection Fourier transform infrared spectroscopy (FTIR-ATR). The auxiliary electric field constrained the jet bending instability and the fiber deposition became controllable. At target speeds of 0.9 m s −1 90% of the fibers had aligned within 2°, whereas the angular spread was 70° without the use of auxiliary electrodes. It was even possible to orient fibers perpendicular to the rotational direction of the target. The fiber diameter became smaller and its distribution narrower, while according to the FTIR-ATR measurement the molecular orientation of the polymer was unaltered. This study comprehensively documents the feasibility of directed fiber deposition and offers an easy upgrade to existing electrospinning setups. (paper)

Aiming of Kirkpatrick-Baez microscope based on auxiliary optical system

International Nuclear Information System (INIS)

Huang Shengling; Mu Baozhong; Yi Shengzhen; Wang Xin; Wang Zhanshan; Ding Yongkun; Miao Wenyong; Dong Jianjun

2009-01-01

An auxiliary optical system has been designed, which can provide precise positioning for aiming Kirkpatrick-Baez (KB) microscope object location. An 8 keV X-ray imaging system by KB microscope with periodic multilayer films has been designed. The field of view and depth of field in the resolution of 5 μm are got, and then the corresponding point and depth of field in diagnostic experiments are calculated. Based on the object-image relations and precision of the KB microscope, an auxiliary visible light imaging system is designed and X-ray imaging experiments are performed, which can achieve equivalent aiming between the visible imaging system and the KB microscope. The results show that ±20 μm vertical axis plane and ±300 μm axial accuracy are achieved through the auxiliary optical path, which can meet the object point positioning requirements of the KB microscope. (authors)

Demonstration of Autonomous Rendezvous Technology (DART) Project Summary

Science.gov (United States)

Rumford, TImothy E.

2003-01-01

Since the 1960's, NASA has performed numerous rendezvous and docking missions. The common element of all US rendezvous and docking is that the spacecraft has always been piloted by astronauts. Only the Russian Space Program has developed and demonstrated an autonomous capability. The Demonstration of Autonomous Rendezvous Technology (DART) project currently funded under NASA's Space Launch Initiative (SLI) Cycle I, provides a key step in establishing an autonomous rendezvous capability for the United States. DART's objective is to demonstrate, in space, the hardware and software necessary for autonomous rendezvous. Orbital Sciences Corporation intends to integrate an Advanced Video Guidance Sensor and Autonomous Rendezvous and Proximity Operations algorithms into a Pegasus upper stage in order to demonstrate the capability to autonomously rendezvous with a target currently in orbit. The DART mission will occur in April 2004. The launch site will be Vandenburg AFB and the launch vehicle will be a Pegasus XL equipped with a Hydrazine Auxiliary Propulsion System 4th stage. All mission objectives will be completed within a 24 hour period. The paper provides a summary of mission objectives, mission overview and a discussion on the design features of the chase and target vehicles.

Reaction of hydrazine hydrate with oxalic acid: synthesis and crystal structure of dihydrazinium oxalate

OpenAIRE

Selvakumar, Rajendran; Premkumar, Thathan; Manivannan, Vadivelu; Saravanan, Kaliannan; Govindarajan, Subbiah

2014-01-01

The reaction of oxalic acid with hydrazine hydrate (in appropriate mole ratio) forms the dihydrazinium oxalate under specific experimental condition. The title compound is a molecular salt containing two discrete hydrazinium cations and an oxalate anion. The oxalate anion is perfectly planar and there is a crystallographic centre of symmetry in the middle of the C-C bond. The C-O bond distances are almost equal indicating the presence of resonance in the oxalate ion. The crystal packing is st...

In-Space Propulsion (346620) Technology Project

Data.gov (United States)

National Aeronautics and Space Administration — Technologies include, but are not limited to, electric and advanced chemical propulsion, propellantless propulsion such as aerocapture and solar sails, sample return...

Applied Hts Bulks and Wires to Rotating Machines for Marine Propulsion

Science.gov (United States)

Miki, M.; Felder, B.; Kimura, Y.; Tsuzuki, K.; Taguchi, R.; Shiliang, Y.; Xu, Y.; Ida, T.; Izumi, M.

2010-04-01

High-temperature superconductors allow a compact and efficient way to provide high-torque density to rotating machines with excellent operation. A field pole, providing flux density of more than 1.5 T around the armature, was initially designed for an axial-gap type with the flux parallel to the rotor axis. Melt-growth Gd-123 bulks as well as Bi-2223 wire windings have been successfully assembled on the rotor disk. No iron core was used, though being an auxiliary flux control found in most HTS motors. Both bulk and wire types have realized a practical motor operation within a limited output range. For bulks, a 15 kW, 720 rpm, synchronous motor was designed and tested in the group of TUMSAT, Kitano Seiki and University of Fukui. A bulk field pole was cooled down by liquid nitrogen and was magnetized in the motor. To enhance the output power to more than 30 kW, we developed a thermosyphon system using condensed neon. Another field pole with HTS wire for large-scale marine propulsion is also discussed on a 100 kW, 230 rpm tested machine. A closed-cycle condensed neon associated with thermal insulation is also reported.

A Conceptual Tree of Laser Propulsion

International Nuclear Information System (INIS)

Pakhomov, Andrew V.; Sinko, John E.

2008-01-01

An original attempt to develop a conceptual tree for laser propulsion is offered. The tree provides a systematic view for practically all possible laser propulsion concepts and all inter-conceptual links, based on propellant phases and phase transfers. It also helps to see which fields of laser propulsion have been already thoroughly explored, where the next effort must be applied, and which paths should be taken with proper care or avoided entirely

14 CFR 33.96 - Engine tests in auxiliary power unit (APU) mode.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine tests in auxiliary power unit (APU... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.96 Engine tests in auxiliary power unit (APU) mode. If the engine is designed with a propeller brake which...

Powersail High Power Propulsion System Design Study

Science.gov (United States)

Gulczinski, Frank S., III

2000-11-01

A desire by the United States Air Force to exploit the space environment has led to a need for increased on-orbit electrical power availability. To enable this, the Air Force Research Laboratory Space Vehicles Directorate (AFRL/ VS) is developing Powersail: a two-phased program to demonstrate high power (100 kW to 1 MW) capability in space using a deployable, flexible solar array connected to the host spacecraft using a slack umbilical. The first phase will be a proof-of-concept demonstration at 50 kW, followed by the second phase, an operational system at full power. In support of this program, the AFRL propulsion Directorate's Spacecraft Propulsion Branch (AFRL/PRS ) at Edwards AFB has commissioned a design study of the Powersail High Power Propulsion System. The purpose of this study, the results of which are summarized in this paper, is to perform mission and design trades to identify potential full-power applications (both near-Earth and interplanetary) and the corresponding propulsion system requirements and design. The design study shall farther identify a suitable low power demonstration flight that maximizes risk reduction for the fully operational system. This propulsion system is expected to be threefold: (1) primary propulsion for moving the entire vehicle, (2) a propulsion unit that maintains the solar array position relative to the host spacecraft, and (3) control propulsion for maintaining proper orientation for the flexible solar array.

Optimization of extended propulsion time nuclear-electric propulsion trajectories

Science.gov (United States)

Sauer, C. G., Jr.

1981-01-01

This paper presents the methodology used in optimizing extended propulsion time NEP missions considering realistic thruster lifetime constraints. These missions consist of a powered spiral escape from a 700-km circular orbit at the earth, followed by a powered heliocentric transfer with an optimized coast phase, and terminating in a spiral capture phase at the target planet. This analysis is most applicable to those missions with very high energy requirements such as outer planet orbiter missions or sample return missions where the total propulsion time could greatly exceed the expected lifetime of an individual thruster. This methodology has been applied to the investigation of NEP missions to the outer planets where examples are presented of both constrained and optimized trajectories.

Breakthrough Propulsion Physics Project: Project Management Methods

Science.gov (United States)

Millis, Marc G.

2004-01-01

To leap past the limitations of existing propulsion, the NASA Breakthrough Propulsion Physics (BPP) Project seeks further advancements in physics from which new propulsion methods can eventually be derived. Three visionary breakthroughs are sought: (1) propulsion that requires no propellant, (2) propulsion that circumvents existing speed limits, and (3) breakthrough methods of energy production to power such devices. Because these propulsion goals are presumably far from fruition, a special emphasis is to identify credible research that will make measurable progress toward these goals in the near-term. The management techniques to address this challenge are presented, with a special emphasis on the process used to review, prioritize, and select research tasks. This selection process includes these key features: (a) research tasks are constrained to only address the immediate unknowns, curious effects or critical issues, (b) reliability of assertions is more important than the implications of the assertions, which includes the practice where the reviewers judge credibility rather than feasibility, and (c) total scores are obtained by multiplying the criteria scores rather than by adding. Lessons learned and revisions planned are discussed.

An Overview of Cube-Satellite Propulsion Technologies and Trends

Directory of Open Access Journals (Sweden)

Akshay Reddy Tummala

2017-12-01

Full Text Available CubeSats provide a cost effective means to perform scientific and technological studies in space. Due to their affordability, CubeSat technologies have been diversely studied and developed by educational institutions, companies and space organizations all over the world. The CubeSat technology that is surveyed in this paper is the propulsion system. A propulsion system is the primary mobility device of a spacecraft and helps with orbit modifications and attitude control. This paper provides an overview of micro-propulsion technologies that have been developed or are currently being developed for CubeSats. Some of the micro-propulsion technologies listed have also flown as secondary propulsion systems on larger spacecraft. Operating principles and key design considerations for each class of propulsion system are outlined. Finally, the performance factors of micro-propulsion systems have been summarized in terms of: first, a comparison of thrust and specific impulse for all propulsion systems; second, a comparison of power and specific impulse, as also thrust-to-power ratio and specific impulse for electric propulsion systems.

30 CFR 57.22208 - Auxiliary fans (I-A, II-A, III, and V-A mines).

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Auxiliary fans (I-A, II-A, III, and V-A mines... fans (I-A, II-A, III, and V-A mines). (a) Auxiliary fans, except fans used in shops and other areas... applicable requirements of 30 CFR part 18, and be operated so that recirculation is minimized. Auxiliary fans...

Propulsion of liposomes using bacterial motors

International Nuclear Information System (INIS)

Zhang Zhenhai; Li Kejie; Li Zhifei; Yu Wei; Xie Zhihong; Shi Zhiguo

2013-01-01

Here we describe the utilization of flagellated bacteria as actuators to propel spherical liposomes by attaching bacteria to the liposome surface. Bacteria were stably attached to liposomes using a cross-linking antibody. The effect of the number of attached bacteria on propulsion speed was experimentally determined. The effects of bacterial propulsion on the bacteria–antibody–liposome complex were stochastic. We demonstrated that liposomal mobility increased when bacteria were attached, and the propulsion speed correlated with the number of bacteria. (paper)

Exotic power and propulsion concepts

International Nuclear Information System (INIS)

Forward, R.L.

1990-01-01

The status of some exotic physical phenomena and unconventional spacecraft concepts that might produce breakthroughs in power and propulsion in the 21st Century are reviewed. The subjects covered include: electric, nuclear fission, nuclear fusion, antimatter, high energy density materials, metallic hydrogen, laser thermal, solar thermal, solar sail, magnetic sail, and tether propulsion

A novel approach for high precision rapid potentiometric titrations: application to hydrazine assay.

Science.gov (United States)

Sahoo, P; Malathi, N; Ananthanarayanan, R; Praveen, K; Murali, N

2011-11-01

We propose a high precision rapid personal computer (PC) based potentiometric titration technique using a specially designed mini-cell to carry out redox titrations for assay of chemicals in quality control laboratories attached to industrial, R&D, and nuclear establishments. Using this technique a few microlitre of sample (50-100 μl) in a total volume of ~2 ml solution can be titrated and the waste generated after titration is extremely low comparing to that obtained from the conventional titration technique. The entire titration including online data acquisition followed by immediate offline analysis of data to get information about concentration of unknown sample is completed within a couple of minutes (about 2 min). This facility has been created using a new class of sensors, viz., pulsating sensors developed in-house. The basic concept in designing such instrument and the salient features of the titration device are presented in this paper. The performance of the titration facility was examined by conducting some of the high resolution redox titrations using dilute solutions--hydrazine against KIO(3) in HCl medium, Fe(II) against Ce(IV) and uranium using Davies-Gray method. The precision of titrations using this innovative approach lies between 0.048% and 1.0% relative standard deviation in different redox titrations. With the evolution of this rapid PC based titrator it was possible to develop a simple but high precision potentiometric titration technique for quick determination of hydrazine in nuclear fuel dissolver solution in the context of reprocessing of spent nuclear fuel in fast breeder reactors. © 2011 American Institute of Physics

Bayesian Analysis of Geostatistical Models With an Auxiliary Lattice

KAUST Repository

Park, Jincheol

2012-04-01

The Gaussian geostatistical model has been widely used for modeling spatial data. However, this model suffers from a severe difficulty in computation: it requires users to invert a large covariance matrix. This is infeasible when the number of observations is large. In this article, we propose an auxiliary lattice-based approach for tackling this difficulty. By introducing an auxiliary lattice to the space of observations and defining a Gaussian Markov random field on the auxiliary lattice, our model completely avoids the requirement of matrix inversion. It is remarkable that the computational complexity of our method is only O(n), where n is the number of observations. Hence, our method can be applied to very large datasets with reasonable computational (CPU) times. The numerical results indicate that our model can approximate Gaussian random fields very well in terms of predictions, even for those with long correlation lengths. For real data examples, our model can generally outperform conventional Gaussian random field models in both prediction errors and CPU times. Supplemental materials for the article are available online. © 2012 American Statistical Association, Institute of Mathematical Statistics, and Interface Foundation of North America.

46 CFR 182.620 - Auxiliary means of steering.

Science.gov (United States)

2010-10-01

... TONS) MACHINERY INSTALLATION Steering Systems § 182.620 Auxiliary means of steering. (a) Except as... personnel hazards during normal or heavy weather operation. (b) A suitable hand tiller may be acceptable as...

Operationally efficient propulsion system study (OEPSS) data book. Volume 6; Space Transfer Propulsion Operational Efficiency Study Task of OEPSS

Science.gov (United States)

Harmon, Timothy J.

1992-01-01

This document is the final report for the Space Transfer Propulsion Operational Efficiency Study Task of the Operationally Efficient Propulsion System Study (OEPSS) conducted by the Rocketdyne Division of Rockwell International. This Study task studied, evaluated and identified design concepts and technologies which minimized launch and in-space operations and optimized in-space vehicle propulsion system operability.

Auxiliary Armed Forces and Innovations in Security Governance in Mozambique’s Civil War

NARCIS (Netherlands)

Jentzsch, C.

2017-01-01

Who rules during the civil war? This article argues that the concept of armed group governance must be expanded to include auxiliary armed forces linked to rebels or the government. Comparing the organization of rebel and government auxiliaries, the article demonstrates that security governance

Stereoselective conjugate radical additions: application of a fluorous oxazolidinone chiral auxiliary for efficient tin removal.

Science.gov (United States)

Hein, Jason E; Zimmerman, Jake; Sibi, Mukund P; Hultin, Philip G

2005-06-23

[reaction: see text] A series of asymmetric free-radical-mediated intermolecular conjugate additions using a fluorous oxazolidinone chiral auxiliary has been completed. The fluorous auxiliary facilitated product isolation using fluorous solid phase extractions (FSPE), effectively removing excess organic and organometallic reagents. Parallel reactions carried out with a similar but nonfluorous norephedrine-derived oxazolidinone demonstrated the superior stereoselectivity and purification obtainable with the fluorous chiral auxiliary.

Auxiliary power unit for moving a vehicle

Science.gov (United States)

Akasam, Sivaprasad [Peoria, IL; Johnson, Kris W [Peoria, IL; Johnson, Matthew D [Peoria, IL; Slone, Larry M [Washington, IL; Welter, James Milton [Chillicothe, IL

2009-02-03

A power system is provided having at least one traction device and a primary power source configured to power the at least one traction device. In addition, the power system includes an auxiliary power source also configured to power the at least one traction device.

An Auxiliary Equation for the Bellman Equation in a One-Dimensional Ergodic Control

International Nuclear Information System (INIS)

Fujita, Y.

2001-01-01

In this paper we consider the Bellman equation in a one-dimensional ergodic control. Our aim is to show the existence and the uniqueness of its solution under general assumptions. For this purpose we introduce an auxiliary equation whose solution gives the invariant measure of the diffusion corresponding to an optimal control. Using this solution, we construct a solution to the Bellman equation. Our method of using this auxiliary equation has two advantages in the one-dimensional case. First, we can solve the Bellman equation under general assumptions. Second, this auxiliary equation gives an optimal Markov control explicitly in many examples

TMI-2 auxiliary building elevator shaft and pit decontamination

Energy Technology Data Exchange (ETDEWEB)

Bengel, T.G.

1986-01-01

Decontamination of the elevator pit and shaft in the auxiliary building at Three Mile Island Unit 2 (TMI-2) was performed to remove high radiation and contamination levels which prevented personnel from utilizing the elevator. The radiation and contamination levels in the TMI-2 auxiliary building elevator shaft have been reduced to the point where plant personnel are again permitted to ride in the elevator without a radiation work permit, with the exception of access to the 281-ft (basement) level. Based on the declassification and expanded use of the elevator, the task goal has been met. The tax expended 16.16 man-rem and 621 man-hours.

Operations of a Radioisotope-based Propulsion System Enabling CubeSat Exploration of the Outer Planets

Energy Technology Data Exchange (ETDEWEB)

Dr. Steven Howe; Nathan Jerred; Troy Howe; Adarsh Rajguru

2014-05-01

Exploration to the outer planets is an ongoing endeavor but in the current economical environment, cost reduction is the forefront of all concern. The success of small satellites such as CubeSats launched to Near-Earth Orbit has lead to examine their potential use to achieve cheaper science for deep space applications. However, to achieve lower cost missions; hardware, launch and operations costs must be minimized. Additionally, as we push towards smaller exploration beds with relative limited power sources, allowing for adequate communication back to Earth is imperative. Researchers at the Center for Space Nuclear Research are developing the potential of utilizing an advanced, radioisotope-based system. This system will be capable of providing both the propulsion power needed to reach the destination and the additional requirements needed to maintain communication while at location. Presented here are a basic trajectory analysis, communication link budget and concept of operations of a dual-mode (thermal and electric) radioisotope-based propulsion system, for a proposed mission to Enceladus (Saturnian icy moon) using a 6U CubeSat payload. The radioisotope system being proposed will be the integration of three sub-systems working together to achieve the overall mission. At the core of the system, stored thermal energy from radioisotope decay is transferred to a passing propellant to achieve high thrust – useful for quick orbital maneuvering. An auxiliary closed-loop Brayton cycle can be operated in parallel to the thrusting mode to provide short bursts of high power for high data-rate communications back to Earth. Additionally, a thermal photovoltaic (TPV) energy conversion system will use radiation heat losses from the core. This in turn can provide the electrical energy needed to utilize the efficiency of ion propulsion to achieve quick interplanetary transit times. The intelligent operation to handle all functions of this system under optimized conditions adds

Treatment for chronic daily headache by using auxiliary and alternative methods

Directory of Open Access Journals (Sweden)

V. A. Golovacheva

2015-01-01

Full Text Available Chronic daily headache (CDH is one of the top 10 causes of adult disability and one of the 5 most common causes of female disability. To treat patients with CDH is one of the most difficult tasks in neurological practice. Difficulties in managing patients with CHD are associated with the high prevalence of comorbid mental disorders, analgesic abuse, pain syndromes at another site, and misconceptions of a patient about his/her disease. A combination of drug and non-drug therapies is the mainstay of the current approach to treating patients with CDH. Standard, alternative, and auxiliary therapies are identified. The paper describes different types of current auxiliary and alternative therapy used in the world’s leading headache centers and clinics. It describes experience with cerebrolysin used as auxiliary and alternative pharmacotherapies for CDH.

Design and Experiment of Auxiliary Bearing for Helium Blower of HTR-PM

International Nuclear Information System (INIS)

Yang Guojun; Shi Zhengang; Liu Xingnan; Zhao Jingjing

2014-01-01

The helium blower is the important equipment for HTR-PM. Active magnetic bearing (AMB) instead of mechanical bearing is selected to support the rotor of the helium blower. However, one implication of AMB is the requirement to provide the auxiliary bearing to mitigate the effects of failures or overload conditions. The auxiliary bearing is used to support the rotor when the AMB fails to work. It must support the dropping rotor and bear the great impact force and friction heat. The design of the auxiliary bearing is one of the challenging problems in the whole system. It is very important for the helium blower with AMB of HTR-PM to make success. The rotor’s length of helium blower of HTR-PM is about 3.3 m, its weight is about 4000 kg and the rotating speed is 4000 r/min. The axial load is 4500kg, and the radial load is 1950kg. The angular contact ball bearing was selected as the auxiliary bearing. The test rig has been finished. It is difficult to analyze the falling course of the rotor. The preliminary analysis of the dropping rotor was done in the special condition. The impact force of auxiliary bearing was computed for the axial and radial load. And the dropping test of the blower rotor for HTR-10 will be introduced also in this paper. Results offer the important theoretical base for the protector design of the helium blower with AMB for HTR-PM. (author)

New set of auxiliary fields for supergravity theories

International Nuclear Information System (INIS)

Oliveira Rivelles, V. de.

1983-02-01

A brief introduction on supersymmetry is given. The problems with the obtainment of the auxiliary fields in supergravity theories are discussed, after a short presentation of the supersymmetry algebra representations. (L.C.) [pt

Main Propulsion Test Article (MPTA)

Science.gov (United States)

Snoddy, Cynthia

2010-01-01

Scope: The Main Propulsion Test Article integrated the main propulsion subsystem with the clustered Space Shuttle Main Engines, the External Tank and associated GSE. The test program consisted of cryogenic tanking tests and short- and long duration static firings including gimbaling and throttling. The test program was conducted on the S1-C test stand (Position B-2) at the National Space Technology Laboratories (NSTL)/Stennis Space Center. 3 tanking tests and 20 hot fire tests conducted between December 21 1 1977 and December 17, 1980 Configuration: The main propulsion test article consisted of the three space shuttle main engines, flightweight external tank, flightweight aft fuselage, interface section and a boilerplate mid/fwd fuselage truss structure.

NASA's Nuclear Thermal Propulsion Project

Science.gov (United States)

Houts, Michael G.; Mitchell, Doyce P.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Clement, Steven; Borowski, Stanley K.;

76 FR 28795 - Privacy Act of 1974; Department of Homeland Security United States Coast Guard-024 Auxiliary...

Science.gov (United States)

2011-05-18

... 1974; Department of Homeland Security United States Coast Guard-024 Auxiliary Database System of... Security/United States Coast Guard-024 Auxiliary Database (AUXDATA) System of Records.'' This system of...: United States Coast Guard Auxiliary Database (AUXDATA). Security classification: Unclassified. System...

Nuclear merchant ship propulsion

International Nuclear Information System (INIS)

Schroeder, E.; Jager, W.; Schafstall, H.G.

1977-01-01

The operation of about 300 nuclear naval vessels has proven the feasibility of nuclear ship propulsion. Until now six non military ships have been built or are under construction. In the Soviet Union two nuclear icebreakers are in operation, and a third one is under construction. In the western world three prototype merchant ships have been built. Of these ships only the NS OTTO HAHN is in operation and provides valuable experience for future large scale use of nuclear merchant ship propulsion. In many countries studies and plans are made for future nuclear merchant ships. Types of vessels investigated are large containerships, tankers and specialized ships like icebreakers or ice-breaking ships. The future of nuclear merchant ship propulsion depends on three interrelated items: (1) nuclear ship technology; (2) economy of nuclear ship propulsion; (3) legal questions. Nuclear merchant ship technology is based until now on standard ship technology and light water reactor technology. Except for special questions due to the non-stationary type of the plant entirely new problems do not arise. This has been proven by the recent conceptual licensing procedure for a large nuclear containership in Germany. The economics of nuclear propulsion will be under discussion until they are proven by the operation of privately owned lead ships. Unsolved legal questions e.g. in connection with port entry permissions are at present another problem for nuclear shipping. Efforts are made to solve these questions on an international basis. The future development of nuclear energy electricity production in large land based plants will stimulate the employment of smaller units. Any future development of long distance sea transport will have to take this opportunity of a reliable and economic energy supply into account

Direction of Impurity Pinch and Auxiliary Heating in Tokamak Plasmas

International Nuclear Information System (INIS)

Angioni, C.; Peeters, A.G.

2006-01-01

A mechanism of particle pinch for trace impurities in tokamak plasmas, arising from the effect of parallel velocity fluctuations in the presence of a turbulent electrostatic potential, is identified analytically by means of a reduced fluid model and verified numerically with a gyrokinetic code for the first time. The direction of such a pinch reverses as a function of the direction of rotation of the turbulence in agreement with the impurity pinch reversal observed in some experiments when moving from dominant auxiliary ion heating to dominant auxiliary electron heating

An Airbreathing Launch Vehicle Design with Turbine-Based Low-Speed Propulsion and Dual Mode Scramjet High-Speed Propulsion

Science.gov (United States)

Moses, P. L.; Bouchard, K. A.; Vause, R. F.; Pinckney, S. Z.; Ferlemann, S. M.; Leonard, C. P.; Taylor, L. W., III; Robinson, J. S.; Martin, J. G.; Petley, D. H.

1999-01-01

Airbreathing launch vehicles continue to be a subject of great interest in the space access community. In particular, horizontal takeoff and horizontal landing vehicles are attractive with their airplane-like benefits and flexibility for future space launch requirements. The most promising of these concepts involve airframe integrated propulsion systems, in which the external undersurface of the vehicle forms part of the propulsion flowpath. Combining of airframe and engine functions in this manner involves all of the design disciplines interacting at once. Design and optimization of these configurations is a most difficult activity, requiring a multi-discipline process to analytically resolve the numerous interactions among the design variables. This paper describes the design and optimization of one configuration in this vehicle class, a lifting body with turbine-based low-speed propulsion. The integration of propulsion and airframe, both from an aero-propulsive and mechanical perspective are addressed. This paper primarily focuses on the design details of the preferred configuration and the analyses performed to assess its performance. The integration of both low-speed and high-speed propulsion is covered. Structural and mechanical designs are described along with materials and technologies used. Propellant and systems packaging are shown and the mission-sized vehicle weights are disclosed.

Propulsive options for a manned Mars transportation system

International Nuclear Information System (INIS)

Braun, R.D.; Blersch, D.J.

1989-01-01

In this investigation, five potential manned Mars transportation systems are compared. These options include: (1) a single vehicle, chemically propelled (CHEM) option, (2) a single vehicle, nuclear thermal propulsion (NTP) option, (3) a single vehicle solar electric propulsion (SEP) option, (4) a single vehicle hybrid nuclear electric propulsion (NEP)/CHEM option, and (5) a dual vehicle option (NEP cargo spacecraft and CHEM manned vehicle). In addition to utilizing the initial vehicle weight in low-earth orbit as a measure of mission feasibility, this study addresses the major technological barriers each propulsive scenario must surpass. It is shown that instead of a single clearly superior propulsion system, each means of propulsion may be favored depending upon the specified program policy and the extent of the desired manned flight time. Furthermore, the effect which aerobraking and multiple transfer cycles have upon mission feasibility is considered. 18 refs

Aging assessment of auxiliary feedwater systems

International Nuclear Information System (INIS)

Casada, D.A.

1989-01-01

A study of Pressurized Water Reactor Auxiliary Feedwater (AFW) Systems has been conducted by Oak Ridge National Laboratory (ORNL) under the auspices of the Nuclear Regulatory Commission's Nuclear Plant Aging Research Program. The study has reviewed historical failure experience and current monitoring practices for the AFW System. This paper provides an overview of the study approach and results. 7 figs

Renormalization of supersymmetric models without using auxiliary fields

International Nuclear Information System (INIS)

Urbanek, P.

1986-01-01

Previously a linear representation of supersymmetry (Ss) was used in investigations of renormalizability. There auxiliary fields have been introduced in order that the Ss-algebra closes 'off-shell'. When the auxiliary fields are eliminated by their equations of motion, the Ss representation becomes nonlinear and Ss closes only 'on-shell'. Following O.Piguet and K.Sibold 1984 Ss is expressed through Ward identities which are formulated as functional variations of the generating functional of the Green functions. These functional operators form a closed algebra, a fact essential for the proof of renormalizability, which is given. It is not necessary to use a specific subtraction scheme in the Green functions. The procedure is applied to the Wess-Zumino model and the supersymmetric extension of the quantum electrodynamics. 15 refs. (qui)

Auxiliary equipment cooling circuit in nuclear reactors

International Nuclear Information System (INIS)

Yanagisawa, Ko.

1986-01-01

Purpose: To prevent the propagation of bacterias that transform NO 2 into NO 3 in auxiliary equipment coolants using corrosion inhibitors of nitrite type in BWR type reactors. Method: In auxiliary equipments coolant systems, water quality is controlled by using purified water as supplement water and nitrite such as Na 2 NO 2 as the corrosion inhibitors. However, in the circumstance where dissolved oxygen is present, bacteria propagate to oxidize NO 2 into NO 3 . Thus, NO 2 at 200 ppm is reduced to 20 ppm. In view of the above, a surge tank supplied from water supplement line is connected in series and a deaeration device is disposed thereto. Since the presence of dissolved oxygen causes the bacteria to propagate it is desired that the dissolved oxygen density in the supplement water is less than 5 ppm. Deaeration and pressure reduction in the surge tank can remove the dissolved oxygen, prevent NO 3 increase and also prevent stress corrosion cracks in the system pipeways. (Horiuchi, T.)

Distributed propulsion for ships

OpenAIRE

Nylund, Vilde

2017-01-01

It is anticipated that using distributed electric propulsion (DEP) on conventional ships will increase the total propulsive efficiency. This is mainly due to two reasons; firstly, because the total propeller disk area can be increased. Secondly, because each propeller can be optimised for the local wake where it is operating. In this work, the benefits of using DEP has been investigated for a 14 000 TEU container ship. Based on a literary study of the present state of propeller modelling ...

A novel nuclear-powered propulsion system for ship

International Nuclear Information System (INIS)

Liu Tao; Han Weishi

2003-01-01

A novel nuclear-powered propulsion system for ship is presented in this paper. In this system, a minitype liquid sodium-cooled reactor is used as power; alkali-metal thermal-to-electric conversion (AMTEC) cells are utilized to transform the heat energy to electric energy and superconducting magneto-hydrodynamic (MHD) work as propulsion. This nuclear-powered propulsion system has great advantages in low noise, high speed, long survivability and simple manipulation. It has great significance for the development of propulsion system. (author)

Center for Advanced Space Propulsion Second Annual Technical Symposium Proceedings

Science.gov (United States)

1990-01-01

The proceedings for the Center for Advanced Space Propulsion Second Annual Technical Symposium are divided as follows: Chemical Propulsion, CFD; Space Propulsion; Electric Propulsion; Artificial Intelligence; Low-G Fluid Management; and Rocket Engine Materials.

New data on the reaction of 1,4-bifunctional derivatives of hydrazine with 1,3-diketones

International Nuclear Information System (INIS)

Zelenin, K.N.; Solod, O.V.; Tomchin, A.B.

1987-01-01

As a function of the conditions of the reaction and the structure of the reagents, mono- and bis-adducts of different structure - 5-hydroxy- and 5-hydrazino-2-pyrazolines, mono- and bis(hydrazones), and the corresponding pyrazoles - are formed in the reaction of hydrazine derivatives - aminoguanidine nitrate, 4-phenylsemicarbazide, amidrazonium iodides, and some thiosemicarbazides - with acetylacetone and dibenzoylmethane. The conditions of the formation of these products and the features of their structure were examined

An Investigation of Bilateral Symmetry During Manual Wheelchair Propulsion.

Science.gov (United States)

Soltau, Shelby L; Slowik, Jonathan S; Requejo, Philip S; Mulroy, Sara J; Neptune, Richard R

2015-01-01

Studies of manual wheelchair propulsion often assume bilateral symmetry to simplify data collection, processing, and analysis. However, the validity of this assumption is unclear. Most investigations of wheelchair propulsion symmetry have been limited by a relatively small sample size and a focus on a single propulsion condition (e.g., level propulsion at self-selected speed). The purpose of this study was to evaluate bilateral symmetry during manual wheelchair propulsion in a large group of subjects across different propulsion conditions. Three-dimensional kinematics and handrim kinetics along with spatiotemporal variables were collected and processed from 80 subjects with paraplegia while propelling their wheelchairs on a stationary ergometer during three different conditions: level propulsion at their self-selected speed (free), level propulsion at their fastest comfortable speed (fast), and propulsion on an 8% grade at their level, self-selected speed (graded). All kinematic variables had significant side-to-side differences, primarily in the graded condition. Push angle was the only spatiotemporal variable with a significant side-to-side difference, and only during the graded condition. No kinetic variables had significant side-to-side differences. The magnitudes of the kinematic differences were low, with only one difference exceeding 5°. With differences of such small magnitude, the bilateral symmetry assumption appears to be reasonable during manual wheelchair propulsion in subjects without significant upper-extremity pain or impairment. However, larger asymmetries may exist in individuals with secondary injuries and pain in their upper extremity and different etiologies of their neurological impairment.

Loss Model and Efficiency Analysis of Tram Auxiliary Converter Based on a SiC Device

Directory of Open Access Journals (Sweden)

Hao Liu

2017-12-01

Full Text Available Currently, the auxiliary converter in the auxiliary power supply system of a modern tram adopts Si IGBT as its switching device and with the 1700 V/225 A SiC MOSFET module commercially available from Cree, an auxiliary converter using all SiC devices is now possible. A SiC auxiliary converter prototype is developed during this study. The author(s derive the loss calculation formula of the SiC auxiliary converter according to the system topology and principle and each part loss in this system can be calculated based on the device datasheet. Then, the static and dynamic characteristics of the SiC MOSFET module used in the system are tested, which aids in fully understanding the performance of the SiC devices and provides data support for the establishment of the PLECS loss simulation model. Additionally, according to the actual circuit parameters, the PLECS loss simulation model is set up. This simulation model can simulate the actual operating conditions of the auxiliary converter system and calculate the loss of each switching device. Finally, the loss of the SiC auxiliary converter prototype is measured and through comparison it is found that the loss calculation theory and PLECS loss simulation model is valuable. Furthermore, the thermal images of the system can prove the conclusion about loss distribution to some extent. Moreover, these two methods have the advantages of less variables and fast calculation for high power applications. The loss models may aid in optimizing the switching frequency and improving the efficiency of the system.

An Analytical Method of Auxiliary Sources Solution for Plane Wave Scattering by Impedance Cylinders

DEFF Research Database (Denmark)

Larsen, Niels Vesterdal; Breinbjerg, Olav

2004-01-01

Analytical Method of Auxiliary Sources solutions for plane wave scattering by circular impedance cylinders are derived by transformation of the exact eigenfunction series solutions employing the Hankel function wave transformation. The analytical Method of Auxiliary Sources solution thus obtained...

An overview of the NASA Advanced Propulsion Concepts program

International Nuclear Information System (INIS)

Curran, F.M.; Bennett, G.L.; Frisbee, R.H.; Sercel, J.C.; Lapointe, M.R.

1992-07-01

NASA Advanced Propulsion Concepts (APC) program for the development of long-term space propulsion system schemes is managed by both NASA-Lewis and the JPL and is tasked with the identification and conceptual development of high-risk/high-payoff configurations. Both theoretical and experimental investigations have been undertaken in technology areas deemed essential to the implementation of candidate concepts. These APC candidates encompass very high energy density chemical propulsion systems, advanced electric propulsion systems, and an antiproton-catalyzed nuclear propulsion concept. A development status evaluation is presented for these systems. 45 refs

46 CFR 121.620 - Propulsion engine control systems.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Propulsion engine control systems. 121.620 Section 121... Propulsion engine control systems. (a) A vessel must have two independent means of controlling each propulsion engine. Control must be provided for the engine speed, direction of shaft rotation, and engine...

Monofilament Vaporization Propulsion (MVP) System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Monofilament Vaporization Propulsion (MVP) is a new propulsion technology targeted at secondary payload applications. It does not compromise on performance while...

Synthesis, Characterization, and Biological Evaluation of certain 6-methyl-2(3H)-benzo-1, 3-thiazolyl-1'-ethylidene-2-(o, p- Substituted Acetophenones) Hydrazine Analogs.

Science.gov (United States)

Alang, G; Kaur, G; Kaur, R; Singh, A; Tiwari, R

2010-10-01

In the present study, five new derivatives (GG4 to GG8) of benzothiazoles were synthesized and evaluated against Staphylococcus aureus (MTCC 737), Pseudomonas aeruginosa (MTCC 424), Escherichia coli (MTCC 1687), and yeast-like fungi Candida tropicalis. p-Toluidine on treatment with ammonium thiocynate formed 2-benzothiazolamines (II), which on reaction with hydrazine hydrate formed a hydrazino derivative (III). Compounds GG4 to GG8 were synthesized by reacting the hydrazine derivative with different acetophenones. All the synthesized compounds were identified by IR and (1)H-NMR, and antimicrobial activity was performed on the synthesized compounds. Presence of NO(2), Br, OCH(3), and Cl groups to the substituted benzothiazole enhanced the antibacterial and antifungal activities.

46 CFR 184.620 - Propulsion engine control systems.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Propulsion engine control systems. 184.620 Section 184... Communications Systems § 184.620 Propulsion engine control systems. (a) A vessel must have two independent means of controlling each propulsion engine. Control must be provided for the engine speed, direction of...

In-Space Propulsion Technologies for Robotic Exploration of the Solar System

Science.gov (United States)

Johnson, Les; Meyer, Rae Ann; Frame, Kyle

2006-01-01

Supporting NASA's Science Mission Directorate, the In-Space Propulsion Technology Program is developing the next generation of space propulsion technologies for robotic, deep-space exploration. Recent technological advancements and demonstrations of key, high-payoff propulsion technologies have been achieved and will be described. Technologies under development and test include aerocapture, solar electric propulsion, solar sail propulsion, and advanced chemical propulsion.

Modifications in Wheelchair Propulsion Technique with Speed.

Science.gov (United States)

Russell, Ian M; Raina, Shashank; Requejo, Philip S; Wilcox, Rand R; Mulroy, Sara; McNitt-Gray, Jill L

2015-01-01

Repetitive loading of the upper limb joints during manual wheelchair (WC) propulsion (WCP) has been identified as a factor that contributes to shoulder pain, leading to loss of independence and decreased quality of life. The purpose of this study was to determine how individual manual WC users with paraplegia modify propulsion mechanics to accommodate expected increases in reaction forces (RFs) generated at the pushrim with self-selected increases in WCP speed. Upper extremity kinematics and pushrim RFs were measured for 40 experienced manual WC users with paraplegia while propelling on a stationary ergometer at self-selected free and fast propulsion speeds. Upper extremity kinematics and kinetics were compared within subject between propulsion speeds. Between group and within-subject differences were determined (α = 0.05). Increased propulsion speed was accompanied by increases in RF magnitude (22 of 40, >10 N) and shoulder net joint moment (NJM, 15 of 40, >10 Nm) and decreases in pushrim contact duration. Within-subject comparison indicated that 27% of participants modified their WCP mechanics with increases in speed by regulating RF orientation relative to the upper extremity segments. Reorientation of the RF relative to the upper extremity segments can be used as an effective strategy for mitigating rotational demands (NJM) imposed on the shoulder at increased propulsion speeds. Identification of propulsion strategies that individuals can use to effectively accommodate for increases in RFs is an important step toward preserving musculoskeletal health of the shoulder and improving health-related quality of life.

Beamed-Energy Propulsion (BEP) Study

Science.gov (United States)

George, Patrick; Beach, Raymond

2012-01-01

The scope of this study was to (1) review and analyze the state-of-art in beamed-energy propulsion (BEP) by identifying potential game-changing applications, (2) formulate a roadmap of technology development, and (3) identify key near-term technology demonstrations to rapidly advance elements of BEP technology to Technology Readiness Level (TRL) 6. The two major areas of interest were launching payloads and space propulsion. More generally, the study was requested and structured to address basic mission feasibility. The attraction of beamed-energy propulsion (BEP) is the potential for high specific impulse while removing the power-generation mass. The rapid advancements in high-energy beamed-power systems and optics over the past 20 years warranted a fresh look at the technology. For launching payloads, the study concluded that using BEP to propel vehicles into space is technically feasible if a commitment to develop new technologies and large investments can be made over long periods of time. From a commercial competitive standpoint, if an advantage of beamed energy for Earth-to-orbit (ETO) is to be found, it will rest with smaller, frequently launched payloads. For space propulsion, the study concluded that using beamed energy to propel vehicles from low Earth orbit to geosynchronous Earth orbit (LEO-GEO) and into deep space is definitely feasible and showed distinct advantages and greater potential over current propulsion technologies. However, this conclusion also assumes that upfront infrastructure investments and commitments to critical technologies will be made over long periods of time. The chief issue, similar to that for payloads, is high infrastructure costs.

The sensitivity of auxiliary examinations in different stages of sporadic Creutzfeldt-Jakob disease

Directory of Open Access Journals (Sweden)

Jiao-jiao JIANG

2017-06-01

Full Text Available Objective To analyze the sensitivity of auxiliary examinations in different periods of sporadic Creutzfeldt-Jakob disease (sCJD. Methods The clinical data of 53 sCJD patients were retrospectively analyzed including the different stages of skull diffusion-weighted magnetic resonance imaging (DWI, 24-hour ambulatory electroencephalogram (EEG, 18F-FDG PET/CT (PET-CT and cerebrospinal fluid 14-3-3 protein. When calculating the sensitivity of an auxiliary examination, the diagnostic criteria were defined by combining the specific clinical manifestations with two or more positive results of other auxiliary examinations. Results There were 24, 53 and 22 sCJD patients, respectively, met the criterion of early (E, middle (M and later (L stage of disease (some patients fit 2 or 3 stages. The sensitivity of DWI (E: 58.3%, M: 85.4%, L: 94.7%, EEG (E: 45.8%, M: 62.7%, L: 77.8%, 14-3-3 protein in cerebrospinal fluid (E: 11.1%, M: 52.9% and PET-CT (E: 80%, M: 100% increased gradually with disease progression. The sensitivity of PET-CT was higher than the other auxiliary examinations for E and M stages; no PET-CT was conducted in L stage. High signal regions mainly distributed in the cortex in E and M stages, but in L stage, no significant difference was found on the distribution of high signal regions between cortex and basal ganglia. Conclusions The sensitivities of the auxiliary examinations were different for sCJD patients in different stages. Reexaminations in different periods may improve the sensitivity for sCJD diagnosis. The sensitivity of PET-CT was high, and the combination of PET-CT and other auxiliary examinations may play a key role in the diagnosis of sCJD. DOI: 10.11855/j.issn.0577-7402.2017.05.15

Advanced Chemical Propulsion for Science Missions

Science.gov (United States)

Liou, Larry

2008-01-01

The advanced chemical propulsion technology area of NASA's In-Space Technology Project is investing in systems and components for increased performance and reduced cost of chemical propulsion technologies applicable to near-term science missions. Presently the primary investment in the advanced chemical propulsion technology area is in the AMBR high temperature storable bipropellant rocket engine. Scheduled to be available for flight development starting in year 2008, AMBR engine shows a 60 kg payload gain in an analysis for the Titan-Enceladus orbiter mission and a 33 percent manufacturing cost reduction over its baseline, state-of-the-art counterpart. Other technologies invested include the reliable lightweight tanks for propellant and the precision propellant management and mixture ratio control. Both technologies show significant mission benefit, can be applied to any liquid propulsion system, and upon completion of the efforts described in this paper, are at least in parts ready for flight infusion. Details of the technologies are discussed.

Nuclear thermal propulsion workshop overview

International Nuclear Information System (INIS)

Clark, J.S.

1991-01-01

NASA is planning an Exploration Technology Program as part of the Space Exploration Initiative to return U.S. astronauts to the moon, conduct intensive robotic exploration of the moon and Mars, and to conduct a piloted mission to Mars by 2019. Nuclear Propulsion is one of the key technology thrust for the human mission to Mars. The workshop addresses NTP (Nuclear Thermal Rocket) technologies with purpose to: assess the state-of-the-art of nuclear propulsion concepts; assess the potential benefits of the concepts for the mission to Mars; identify critical, enabling technologies; lay-out (first order) technology development plans including facility requirements; and estimate the cost of developing these technologies to flight-ready status. The output from the workshop will serve as a data base for nuclear propulsion project planning

Propulsion controlled aircraft computer

Science.gov (United States)

Cogan, Bruce R. (Inventor)

2010-01-01

A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.

The effect of wheelchair propulsion style on changes in time spent in extreme wrist orientations after a bout of fatiguing propulsion.

Science.gov (United States)

Zukowski, Lisa A; Hass, Chris J; Shechtman, Orit; Christou, Evangelos A; Tillman, Mark D

2017-10-01

This study compared how wheelchair propulsion styles affect changes in percentage of time spent in extreme wrist orientations, which have been associated with median nerve injury, after a fatiguing bout of propulsion. Twenty novice, non-disabled adult males learned arcing (ARC) and semicircular (SEMI) propulsion styles and utilised each to perform a wheelchair fatigue protocol. ARC and SEMI did not significantly differ in terms of changes after the fatigue protocol in percentage of time spent in extreme flexion/extension or radial/ulnar deviation at the push phase beginning or end. A pattern was observed, although not significant, of greater increases in percentage of time spent in extreme wrist extension and ulnar deviation during the push phase beginning and ulnar deviation during the push phase end while utilising SEMI relative to ARC. This study evinces that individual differences are greater than observed changes in extreme wrist orientations for both propulsion styles. Practitioner Summary: How wheelchair propulsion styles change with fatigue in terms of extreme wrist orientations was examined. This study evinces that individual differences are greater than observed changes in extreme wrist orientations for both propulsion styles and point towards the need for future research on individual differences utilising propulsion styles.

Awareness of biomedical waste management among dental professionals and auxiliary staff in Amritsar, India.

Science.gov (United States)

Narang, Ramandeep S; Manchanda, Adesh; Singh, Simarpreet; Verma, Nitin; Padda, Sarfaraz

2012-12-01

The aim of this study was to determine awareness of biomedical waste (BMW) management policies and practices among dental professionals and auxiliary staff in a dental hospital/clinics in Amritsar, India, to inform the development of future policies for effective implementation of BMW rules. The study involved 160 staff members at the Amritsar hospital/clinics (80 dentists and 80 auxiliary staff) to whom a questionnaire was distributed regarding policies, practices and awareness relating to BMW. The questionnaire was first piloted. Completed questionnaires were returned anonymously. The resulting data were statistically tested using the chi-square test for differences between the dentists and auxiliary staff. In respect of BMW management policies, there was a highly significant difference in the responses of the dentists, whose answers suggested far greater knowledge than that of the auxiliaries (Pmanagement practices, the dentists were significantly more aware (Pwaste collection in the hospital and the disposal of various items into different colour-coded bags. As for employee education/awareness, there was a significant difference (Pmanagement among dental auxiliary staff in the dental hospital/clinics in Amritsar and a lack of awareness of some aspects among dentists who work in the hospital/clinics. The results provide the hospital authorities with data upon which they can develop a strategy for improving BMW management.

46 CFR 109.555 - Propulsion boilers.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Propulsion boilers. 109.555 Section 109.555 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.555 Propulsion boilers. The master or person in charge and the engineer in charge shall...

46 CFR 130.120 - Propulsion control.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Propulsion control. 130.120 Section 130.120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS VESSEL CONTROL, AND MISCELLANEOUS EQUIPMENT AND SYSTEMS Vessel Control § 130.120 Propulsion control. (a) Each vessel must have— (1...

Is effective force application in handrim wheelchair propulsion also efficient?

NARCIS (Netherlands)

Bregman, D.J.J.; van Drongelen, S.V.; Veeger, H.E.J.

2009-01-01

Background: Efficiency in manual wheelchair propulsion is low, as is the fraction of the propulsion force that is attributed to the moment of propulsion of the wheelchair. In this study we tested the hypothesis that a tangential propulsion force direction leads to an increase in physiological cost,

Auxiliary facilities on nuclear ship 'MUTSU'

International Nuclear Information System (INIS)

Tsujimura, Shotaro; Takigami, Yoshio.

1989-01-01

The nuclear ship 'MUTSU' has been moored at SEKINEHAMA, MUTU City in AOMORI Prefecture and several tests and works are being carried out on the ship. The construction of the auxiliary facilities for these works on the ship was completed in safety in August 1988. After that the facilities have fulfilled their function. The outlines of design, fabrication and construction of the facilities are described in this paper. (author)

Categorical Data Fusion Using Auxiliary Information

OpenAIRE

Fosdick, Bailey K.; DeYoreo, Maria; Reiter, Jerome P.

2015-01-01

In data fusion, analysts seek to combine information from two databases comprised of disjoint sets of individuals, in which some variables appear in both databases and other variables appear in only one database. Most data fusion techniques rely on variants of conditional independence assumptions. When inappropriate, these assumptions can result in unreliable inferences. We propose a data fusion technique that allows analysts to easily incorporate auxiliary information on the dependence struc...

Progress in the integration of the ITER plant systems in auxiliary buildings

International Nuclear Information System (INIS)

Kotamäki, M.; Cordier, J.-J.; Kuehn, I.; Perrin, J.-L.; Sweeney, S.; Villedary, B.

2016-01-01

Highlights: • Usage of 3D CAD model in ITER configuration management presented. • 3D CAD models efficient in configuration and interface management. • Costly and schedule delaying changes avoided with proper interface management. • ITER buildings construction progressing. - Abstract: The ITER Tokamak machine is located in the center of Tokamak complex buildings consisting of Tokamak, Diagnostic, and Tritium buildings. Around the Tokamak complex there are over 30 auxiliary buildings housing various plant systems serving the Tokamak machine either directly or indirectly. The layout and space allocation of each auxiliary building and plant systems housed by the building are represented in the so-called Configuration Management Models (CMM). These are light 3D CAD models that define the required space envelope and the physical interfaces between the systems and the buildings and in-between the systems. The paper describes the CMM and interface management processes of the ITER auxiliary buildings and plant systems, and discusses the preparations for the plant installation phase. In addition, the current baseline configuration of the ITER plant systems in auxiliary buildings is described together with the recent developments in the configuration of different systems, as well as the current status of the construction of the buildings.

Progress in the integration of the ITER plant systems in auxiliary buildings

Energy Technology Data Exchange (ETDEWEB)

Kotamäki, M., E-mail: miikka.kotamaki@iter.org; Cordier, J.-J.; Kuehn, I.; Perrin, J.-L.; Sweeney, S.; Villedary, B.

2016-11-01

Highlights: • Usage of 3D CAD model in ITER configuration management presented. • 3D CAD models efficient in configuration and interface management. • Costly and schedule delaying changes avoided with proper interface management. • ITER buildings construction progressing. - Abstract: The ITER Tokamak machine is located in the center of Tokamak complex buildings consisting of Tokamak, Diagnostic, and Tritium buildings. Around the Tokamak complex there are over 30 auxiliary buildings housing various plant systems serving the Tokamak machine either directly or indirectly. The layout and space allocation of each auxiliary building and plant systems housed by the building are represented in the so-called Configuration Management Models (CMM). These are light 3D CAD models that define the required space envelope and the physical interfaces between the systems and the buildings and in-between the systems. The paper describes the CMM and interface management processes of the ITER auxiliary buildings and plant systems, and discusses the preparations for the plant installation phase. In addition, the current baseline configuration of the ITER plant systems in auxiliary buildings is described together with the recent developments in the configuration of different systems, as well as the current status of the construction of the buildings.

Energy confinement scaling in tokamaks: some implications of recent experiments with ohmic and strong auxiliary heating

International Nuclear Information System (INIS)

Goldston, R.J.

1984-02-01

Recent results from confinement scaling experiments on tokamaks with ohmic and strong auxiliary heating are reviewed. An attempt is made to draw these results together into a low-density ohmic confinement scaling law, and a scaling law for confinement with auxiliary heating. The auxiliary heating confinement law may also serve to explain the saturation in tau/sub E/ vs anti n/sub e/ observed in some ohmic heating density scaling experiments

46 CFR 52.01-35 - Auxiliary, donkey, fired thermal fluid heater, and heating boilers.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Auxiliary, donkey, fired thermal fluid heater, and... (CONTINUED) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-35 Auxiliary, donkey, fired thermal... requirements for miscellaneous boiler types, such as donkey, fired thermal fluid heater, heating boiler, etc...

A probabilistic evaluation of the Shearon Harris Nuclear Power Plant auxiliary feedwater isolation system

International Nuclear Information System (INIS)

Anoba, R.C.

1989-01-01

This paper reports on a fault tree approach that was used to evaluate the safety significance of modifying the Shearon Harris Auxiliary Feedwater Isolation System. The design modification was a result of on-site reviews which identified a single failure in the Auxiliary Feedwater Isolation circuitry

A cermet fuel reactor for nuclear thermal propulsion

International Nuclear Information System (INIS)

Kruger, G.

1991-01-01

Work on the cermet fuel reactor done in the 1960's by General Electric (GE) and the Argonne National Laboratory (ANL) that had as its goal the development of systems that could be used for nuclear rocket propulsion as well as closed cycle propulsion system designs for ship propulsion, space nuclear propulsion, and other propulsion systems is reviewed. It is concluded that we can have excellent thermal and mechanical performance with cermet fuel. Thousands of hours of testing were performed on the cermet fuel at both GE and AGL, including very rapid transients and some radiation performance history. We conclude that there are no feasibility issues with cermet fuel. What is needed is reactivation of existing technology and qualification testing of a specific fuel form. We believe this can be done with a minimum development risk

Auxiliary feedwater system aging study

International Nuclear Information System (INIS)

Kueck, J.D.

1992-01-01

The Phase 1 Auxiliary Feedwater (AFW) System Aging Study, NUREG/CR-5404 V1, focused on how and to what extent the various AFW system component types fail, how the failures have been and can be detected, and on the value of current testing requirements and practices. This follow-on study, which will be provided in full in NUREG/CR-5404 V2, provides a closure to the Phase 1 Study. For each of the component types and for the various sources of component failure identified in the Phase 1 Study, the methods of failure detection were designated and tabulated and the following findings became evident: Instrumentation and Control (I and C) related failures dominated the group of failures that were detected during demand conditions; many of the potential failure sources not detectable by the current monitoring practices were related to the I and C portion of the system; some component failure modes are actually aggravated by conventional test methods; and several important system functions did not undergo any function verification test. The goal of this follow-on study was to categorize and evaluate the deficiencies in testing identified by Phase 1 and to make specific recommendations for corrective action. In addition, this study presents discussions of alternate, state-of-the-art test methods, and provides a proposed Auxiliary Feedwater Pump test at normal operating pressure which should do much to verify system operability while eliminating degradation

Overview and future prospects of laser plasma propulsion technology

International Nuclear Information System (INIS)

Zheng Zhiyuan; Lu Xin; Zhang Jie

2003-01-01

Due to its high cost, low efficiency, complex operation and unsatisfactory recycling, traditional rocket propulsion by chemical fuels has hindered the exploration of outer space to further limits. With the rapid development of laser and space technology, the new technology of laser propulsion exhibits unique advantages and prospects. The mechanism and current development of laser plasma propulsion are reviewed, with mention of the technical problems and focus issues of laser plasma in micro-flight propulsion

Fitting aerodynamics and propulsion into the puzzle

Science.gov (United States)

Johnston, Patrick J.; Whitehead, Allen H., Jr.; Chapman, Gary T.

1987-01-01

The development of an airbreathing single-stage-to-orbit vehicle, in particular the problems of aerodynamics and propulsion integration, is examined. The boundary layer transition on constant pressure surfaces at hypersonic velocities, and the effects of noise on the transition are investigated. The importance of viscosity, real-gas effects, and drag at hypersonic speeds is discussed. A propulsion system with sufficient propulsive lift to enhance the performance of the vehicle is being developed. The difficulties of engine-airframe integration are analyzed.

NASA's nuclear electric propulsion technology project

International Nuclear Information System (INIS)

Stone, J.R.; Sovey, J.S.

1992-07-01

The National Aeronautics and Space Administration (NASA) has initiated a program to establish the readiness of nuclear electric propulsion (NEP) technology for relatively near-term applications to outer planet robotic science missions with potential future evolution to system for piloted Mars vehicles. This program was initiated in 1991 with a very modest effort identified with nuclear thermal propulsion (NTP); however, NEP is also an integral part of this program and builds upon NASA's Base Research and Technology Program in power and electric propulsion as well as the SP-100 space nuclear power program. The NEP Program will establish the feasibility and practicality of electric propulsion for robotic and piloted solar system exploration. The performance objectives are high specific impulse (200 greater than I(sub sp) greater than 10000 s), high efficiency (over 0.50), and low specific mass. The planning for this program was initially focussed on piloted Mars missions, but has since been redirected to first focus on 100-kW class systems for relatively near-term robotic missions, with possible future evolution to megawatt-and multi-megawatt-class systems applicable to cargo vehicles supporting human missions as well as to the piloted vehicles. This paper reviews current plans and recent progress for the overall nuclear electric propulsion project and closely related activities. 33 refs

Ultrasonic propulsion of kidney stones.

Science.gov (United States)

May, Philip C; Bailey, Michael R; Harper, Jonathan D

2016-05-01

Ultrasonic propulsion is a novel technique that uses short bursts of focused ultrasonic pulses to reposition stones transcutaneously within the renal collecting system and ureter. The purpose of this review is to discuss the initial testing of effectiveness and safety, directions for refinement of technique and technology, and opinions on clinical application. Preclinical studies with a range of probes, interfaces, and outputs have demonstrated feasibility and consistent safety of ultrasonic propulsion with room for increased outputs and refinement toward specific applications. Ultrasonic propulsion was used painlessly and without adverse events to reposition stones in 14 of 15 human study participants without restrictions on patient size, stone size, or stone location. The initial feasibility study showed applicability in a range of clinically relevant situations, including facilitating passage of residual fragments following ureteroscopy or shock wave lithotripsy, moving a large stone at the ureteropelvic junction with relief of pain, and differentiating large stones from a collection of small fragments. Ultrasonic propulsion shows promise as an office-based system for transcutaneously repositioning kidney stones. Potential applications include facilitating expulsion of residual fragments following ureteroscopy or shock wave lithotripsy, repositioning stones prior to treatment, and repositioning obstructing ureteropelvic junction stones into the kidney to alleviate acute renal colic.

Intrinsically safe electrical installations, auxiliary circuits and electric communication equipment

Energy Technology Data Exchange (ETDEWEB)

Herms, C D

1981-11-19

Technical progress has not stopped short of electrical systems in mining, so that three new chapters are new included in the VDE regulations leaflet No. 0118 on 'Installation of electrical systems in underground coal mining'. The regulations on intrinsically safe electric systems, auxiliary circuits and communication systems are briefly described, and grounds for the regulations are presented. The regulations already take account of European regulations on intrinsic safety which will soon be published in a European Regulation on Mine Explosions. In the chapters on auxiliary circuits and communication systems, protection against direct contact, fires, and explosions is discussed as well as the further goal of reliable signal transmission.

Hybrid-electric propulsion for automotive and aviation applications

OpenAIRE

Friedrich, C; Robertson, Paul Andrew

2014-01-01

In parallel with the automotive industry, hybrid-electric propulsion is becoming a viable alternative propulsion technology for the aviation sector and reveals potential advantages including fuel savings, lower pollution, and reduced noise emission. Hybrid-electric propulsion systems can take advantage of the synergy between two technologies by utilizing both internal combustion engines and electric motors together, each operating at their respective optimum conditions...

Synthesis, Characterization, and Biological Evaluation of certain 6-methyl-2(3H)-benzo-1, 3-thiazolyl-1’-ethylidene-2-(o, p- Substituted Acetophenones) Hydrazine Analogs

Science.gov (United States)

Alang, G; Kaur, G; Kaur, R; Singh, A; Tiwari, R

2010-01-01

In the present study, five new derivatives (GG4 to GG8) of benzothiazoles were synthesized and evaluated against Staphylococcus aureus (MTCC 737), Pseudomonas aeruginosa (MTCC 424), Escherichia coli (MTCC 1687), and yeast-like fungi Candida tropicalis. p-Toluidine on treatment with ammonium thiocynate formed 2-benzothiazolamines (II), which on reaction with hydrazine hydrate formed a hydrazino derivative (III). Compounds GG4 to GG8 were synthesized by reacting the hydrazine derivative with different acetophenones. All the synthesized compounds were identified by IR and 1H-NMR, and antimicrobial activity was performed on the synthesized compounds. Presence of NO2, Br, OCH3, and Cl groups to the substituted benzothiazole enhanced the antibacterial and antifungal activities. PMID:21264101

29 CFR Appendix II to Part 1918 - Tables for Selected Miscellaneous Auxiliary Gear (Mandatory)

Science.gov (United States)

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Tables for Selected Miscellaneous Auxiliary Gear (Mandatory) II Appendix II to Part 1918 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND.... 1918, App. II Appendix II to Part 1918—Tables for Selected Miscellaneous Auxiliary Gear (Mandatory...

Electric Motors for Vehicle Propulsion

OpenAIRE

Larsson, Martin

2014-01-01

This work is intended to contribute with knowledge to the area of electic motorsfor propulsion in the vehicle industry. This is done by first studying the differentelectric motors available, the motors suitable for vehicle propulsion are then dividedinto four different types to be studied separately. These four types are thedirect current, induction, permanent magnet and switched reluctance motors. Thedesign and construction are then studied to understand how the different typesdiffer from ea...

Heat removal performance of auxiliary cooling system for the high temperature engineering test reactor during scrams

International Nuclear Information System (INIS)

Takeda, Takeshi; Tachibana, Yukio; Iyoku, Tatsuo; Takenaka, Satsuki

2003-01-01

The auxiliary cooling system of the high temperature engineering test reactor (HTTR) is employed for heat removal as an engineered safety feature when the reactor scrams in an accident when forced circulation can cool the core. The HTTR is the first high temperature gas-cooled reactor in Japan with reactor outlet gas temperature of 950 degree sign C and thermal power of 30 MW. The auxiliary cooling system should cool the core continuously avoiding excessive cold shock to core graphite components and water boiling of itself. Simulation tests on manual trip from 9 MW operation and on loss of off-site electric power from 15 MW operation were carried out in the rise-to-power test up to 20 MW of the HTTR. Heat removal characteristics of the auxiliary cooling system were examined by the tests. Empirical correlations of overall heat transfer coefficients were acquired for a helium/water heat exchanger and air cooler for the auxiliary cooling system. Temperatures of fluids in the auxiliary cooling system were predicted on a scram event from 30 MW operation at 950 degree sign C of the reactor outlet coolant temperature. Under the predicted helium condition of the auxiliary cooling system, integrity of fuel blocks among the core graphite components was investigated by stress analysis. Evaluation results showed that overcooling to the core graphite components and boiling of water in the auxiliary cooling system should be prevented where open area condition of louvers in the air cooler is the full open

Propulsive efficiency of a biomorphic pulsed-jet underwater vehicle

International Nuclear Information System (INIS)

Moslemi, Ali A; Krueger, Paul S

2010-01-01

The effect of the velocity program and duty cycle (St L ) on the propulsive efficiency of pulsed-jet propulsion was studied experimentally on a self-propelled, pulsed-jet underwater vehicle, dubbed Robosquid due to the similarity of essential elements of its propulsion system with squid jet propulsion. Robosquid was tested for jet slug length-to-diameter ratios (L/D) in the range 2-6 and St L in the range 0.2-0.6 with jet velocity programs commanded to be triangular or trapezoidal. Digital particle image velocimetry was used for measuring the impulse and energy of jet pulses to calculate the pulsed-jet propulsive efficiency and compare it with an equivalent steady jet system. Robosquid's Reynolds number (Re) based on average vehicle velocity and vehicle diameter ranged between 1300 and 2700 for the conditions tested. The results indicated better propulsive efficiency of the trapezoidal velocity program (up to 20% higher) compared to the triangular velocity program. Also, an increase in the ratio of the pulsed-jet propulsive efficiency to the equivalent steady jet propulsive efficiency (η P /η P,ss ) was observed as St L increased and L/D decreased. For cases of short L/D and high St L , η P /η P,ss was found to be as high as 1.2, indicating better performance of pulsed jets. This result demonstrates a case where propulsion using essential elements of a biological locomotion system can outperform the traditional mechanical system equivalent in terms of efficiency. It was also found that changes in St L had a proportionately larger effect on propulsive efficiency compared to changes in L/D. A simple model is presented to explain the results in terms of the contribution of over-pressure at the nozzle exit plane associated with the formation of vortex rings with each jet pulse.

Large gap plasma display cell with auxiliary electrodes: macro-cell experiments and two-dimensional modelling

International Nuclear Information System (INIS)

Ouyang, J T; Callegari, Th; Caillier, B; Boeuf, J-P

2003-01-01

In this paper we use a two-dimensional fluid model and a 'macroscopic' PDP cell to investigate the possibility of using large gap configurations with auxiliary electrodes to improve the efficiency of PDP discharge cells. The large gap allows operation in a transient positive column regime where energy is more efficiently deposited into xenon excitation, while the auxiliary electrodes are used to keep reasonable values of the operating voltage. Two types of auxiliary electrode configurations (floating and powered) are considered. The discharge characteristics and the discharge efficiency in exciting xenon are studied with simulations and by measuring the intensity of infrared emission from xenon and visible emission from neon in a macroscopic PDP cell. The results show that an efficient positive column regime can be achieved at reasonably low operating voltages when the auxiliary electrode configuration is carefully designed

A Power-Efficient Propulsion Method for Magnetic Microrobots

Directory of Open Access Journals (Sweden)

Gioia Lucarini

2014-07-01

Full Text Available Current magnetic systems for microrobotic navigation consist of assemblies of electromagnets, which allow for the wireless accurate steering and propulsion of sub-millimetric bodies. However, large numbers of windings and/or high currents are needed in order to generate suitable magnetic fields and gradients. This means that magnetic navigation systems are typically cumbersome and require a lot of power, thus limiting their application fields. In this paper, we propose a novel propulsion method that is able to dramatically reduce the power demand of such systems. This propulsion method was conceived for navigation systems that achieve propulsion by pulling microrobots with magnetic gradients. We compare this power-efficient propulsion method with the traditional pulling propulsion, in the case of a microrobot swimming in a micro-structured confined liquid environment. Results show that both methods are equivalent in terms of accuracy and the velocity of the motion of the microrobots, while the new approach requires only one ninth of the power needed to generate the magnetic gradients. Substantial equivalence is demonstrated also in terms of the manoeuvrability of user-controlled microrobots along a complex path.

Verb and auxiliary movement in agrammatic Broca's aphasia

NARCIS (Netherlands)

Bastiaanse, Y.R.M.; Thompson, C.K.

Verb production in agrammatic Broca's aphasia has repeatedly been shown to be impaired by a number of investigators. Not only is the number of verbs produced often significantly reduced, but verb inflections and auxiliaries are often omitted as well (e.g., Bastiaanse, Jonkers, & Moltmaker-Osinga,

A cermet fuel reactor for nuclear thermal propulsion

Science.gov (United States)

Kruger, Gordon

1991-01-01

Work on the cermet fuel reactor done in the 1960's by General Electric (GE) and the Argonne National Laboratory (ANL) that had as its goal the development of systems that could be used for nuclear rocket propulsion as well as closed cycle propulsion system designs for ship propulsion, space nuclear propulsion, and other propulsion systems is reviewed. It is concluded that the work done in the 1960's has demonstrated that we can have excellent thermal and mechanical performance with cermet fuel. Thousands of hours of testing were performed on the cermet fuel at both GE and AGL, including very rapid transients and some radiation performance history. We conclude that there are no feasibility issues with cermet fuel. What is needed is reactivation of existing technology and qualification testing of a specific fuel form. We believe this can be done with a minimum development risk.

Airbreathing Propulsion An Introduction

CERN Document Server

Bose, Tarit

2012-01-01

Airbreathing Propulsion covers the physics of combustion, fluid and thermo-dynamics, and structural mechanics of airbreathing engines, including piston, turboprop, turbojet, turbofan, and ramjet engines. End-of-chapter exercises allow the reader to practice the fundamental concepts behind airbreathing propulsion, and the included PAGIC computer code will help the reader to examine the relationships between the performance parameters of different engines. Large amounts of data on many different piston, turbojet, and turboprop engines have been compiled for this book and are included as an appendix. This textbook is ideal for senior undergraduate and graduate students studying aeronautical engineering, aerospace engineering, and mechanical engineering.

Hydrazine-based deposition route for device-quality CIGS films

International Nuclear Information System (INIS)

Mitzi, David B.; Yuan, Min; Liu, Wei; Kellock, Andrew J.; Chey, S. Jay; Gignac, Lynne; Schrott, Alex G.

2009-01-01

A simple solution-based approach for depositing CIGS (Cu-In-Ga-Se/S) absorber layers is discussed, with an emphasis on film characterization, interfacial properties and integration into photovoltaic devices. The process involves incorporating all metal and chalcogenide components into a single hydrazine-based solution, spin coating a precursor film, and heat treating in an inert atmosphere, to form the desired CIGS film with up to micron-scaled film thickness and grain size. PV devices (glass/Mo/CIGS/CdS/i-ZnO/ITO) employing the spin-coated CIGS and using processing temperatures below 500 deg. C have yielded power conversion efficiencies of up to 10% (AM 1.5 illumination), without the need for a post-CIGS-deposition treatment in a gaseous Se source or a cyanide-based bath etch. Short-duration low-temperature (T < 200 deg. C ) oxygen treatment of completed devices is shown to have a positive impact on the performance of initially underperforming cells, thereby enabling better performance in devices prepared at temperatures below 500 deg. C

Hydrazine-based deposition route for device-quality CIGS films

Energy Technology Data Exchange (ETDEWEB)

Mitzi, David B. [IBM T. J. Watson Research Center, P. O. Box 218, Yorktown Heights, NY 10598 (United States)], E-mail: dmitzi@us.ibm.com; Yuan, Min; Liu, Wei [IBM T. J. Watson Research Center, P. O. Box 218, Yorktown Heights, NY 10598 (United States); Kellock, Andrew J [IBM Almaden Research Center, 650 Harry Rd, San Jose, CA 95120 (United States); Chey, S Jay; Gignac, Lynne; Schrott, Alex G [IBM T. J. Watson Research Center, P. O. Box 218, Yorktown Heights, NY 10598 (United States)

2009-02-02

A simple solution-based approach for depositing CIGS (Cu-In-Ga-Se/S) absorber layers is discussed, with an emphasis on film characterization, interfacial properties and integration into photovoltaic devices. The process involves incorporating all metal and chalcogenide components into a single hydrazine-based solution, spin coating a precursor film, and heat treating in an inert atmosphere, to form the desired CIGS film with up to micron-scaled film thickness and grain size. PV devices (glass/Mo/CIGS/CdS/i-ZnO/ITO) employing the spin-coated CIGS and using processing temperatures below 500 deg. C have yielded power conversion efficiencies of up to 10% (AM 1.5 illumination), without the need for a post-CIGS-deposition treatment in a gaseous Se source or a cyanide-based bath etch. Short-duration low-temperature (T < 200 deg. C ) oxygen treatment of completed devices is shown to have a positive impact on the performance of initially underperforming cells, thereby enabling better performance in devices prepared at temperatures below 500 deg. C.

Advanced Chemical Propulsion

Science.gov (United States)

Bai, S. Don

2000-01-01

Design, propellant selection, and launch assistance for advanced chemical propulsion system is discussed. Topics discussed include: rocket design, advance fuel and high energy density materials, launch assist, and criteria for fuel selection.

Auxiliary Heat Exchanger Flow Distribution Test

International Nuclear Information System (INIS)

Kaufman, J.S.; Bressler, M.M.

1983-01-01

The Auxiliary Heat Exchanger Flow Distribution Test was the first part of a test program to develop a water-cooled (tube-side), compact heat exchanger for removing heat from the circulating gas in a high-temperature gas-cooled reactor (HTGR). Measurements of velocity and pressure were made with various shell side inlet and outlet configurations. A flow configuration was developed which provides acceptable velocity distribution throughout the heat exchanger without adding excessive pressure drop

Real-time feedback enhances forward propulsion during walking in old adults.

Science.gov (United States)

Franz, Jason R; Maletis, Michela; Kram, Rodger

2014-01-01

Reduced propulsive function during the push-off phase of walking plays a central role in the deterioration of walking ability with age. We used real-time propulsive feedback to test the hypothesis that old adults have an underutilized propulsive reserve available during walking. 8 old adults (mean [SD], age: 72.1 [3.9] years) and 11 young adults (age: 21.0 [1.5] years) participated. For our primary aim, old subjects walked: 1) normally, 2) with visual feedback of their peak propulsive ground reaction forces, and 3) with visual feedback of their medial gastrocnemius electromyographic activity during push-off. We asked those subjects to match a target set to 20% and 40% greater propulsive force or push-off muscle activity than normal walking. We tested young subjects walking normally only to provide reference ground reaction force values. Walking normally, old adults exerted 12.5% smaller peak propulsive forces than young adults (Ppush-off muscle activities when we provided propulsive feedback. Most notably, force feedback elicited propulsive forces that were equal to or 10.5% greater than those of young adults (+20% target, P=0.87; +40% target, P=0.02). With electromyographic feedback, old adults significantly increased their push-off muscle activities but without increasing their propulsive forces. Old adults with propulsive deficits have a considerable and underutilized propulsive reserve available during level walking. Further, real-time propulsive feedback represents a promising therapeutic strategy to improve the forward propulsion of old adults and thus maintain their walking ability and independence. © 2013.

Natural convection in an asymmetrically heated vertical channel with an adiabatic auxiliary plate

International Nuclear Information System (INIS)

Taieb, Soumaya; Hatem, Laatar Ali; Balti, Jalloul

2013-01-01

The effect of an auxiliary plate on natural convection in an asymmetrically heated channel is studied numerically in laminar regime. The computational procedure is made by solving the unsteady two dimensional Navier-Stokes and energy equations. This nonlinear system is integrated by a finite volume approach and then solved in time using the projection method, allowing the decoupling pressure from velocity. More than hundred simulations are performed to determine the best positions of the auxiliary plate that enhance the induced mass flow and the heat transfer rate for modified Rayleigh numbers ranging from Ra m = 10 2 to Ra m = 10 5 . Contour maps are plotted and then used to precise the enhancement rates of the mass flow and the heat transfer for any position of the auxiliary plate in the channel. The numerical results (velocity, pressure and temperature fields) provide detailed information about the evolution of the flow structure according to the geometry considered in this study. In addition, they permit to explain why the mass flow rate and Nusselt number are enhanced for certain positions of the auxiliary plate and are on the contrary deteriorated for others. (authors)

Total synthesis of cytochrome b562 by native chemical ligation using a removable auxiliary

Science.gov (United States)

Low, Donald W.; Hill, Michael G.; Carrasco, Michael R.; Kent, Stephen B. H.; Botti, Paolo

2001-01-01

We have completed the total chemical synthesis of cytochrome b562 and an axial ligand analogue, [SeMet7]cyt b562, by thioester-mediated chemical ligation of unprotected peptide segments. A novel auxiliary-mediated native chemical ligation that enables peptide ligation to be applied to protein sequences lacking cysteine was used. A cleavable thiol-containing auxiliary group, 1-phenyl-2-mercaptoethyl, was added to the α-amino group of one peptide segment to facilitate amide bond-forming ligation. The amine-linked 1-phenyl-2-mercaptoethyl auxiliary was stable to anhydrous hydrogen fluoride used to cleave and deprotect peptides after solid-phase peptide synthesis. Following native chemical ligation with a thioester-containing segment, the auxiliary group was cleanly removed from the newly formed amide bond by treatment with anhydrous hydrogen fluoride, yielding a full-length unmodified polypeptide product. The resulting polypeptide was reconstituted with heme and folded to form the functional protein molecule. Synthetic wild-type cyt b562 exhibited spectroscopic and electrochemical properties identical to the recombinant protein, whereas the engineered [SeMet7]cyt b562 analogue protein was spectroscopically and functionally distinct, with a reduction potential shifted by ≈45 mV. The use of the 1-phenyl-2-mercaptoethyl removable auxiliary reported here will greatly expand the applicability of total protein synthesis by native chemical ligation of unprotected peptide segments. PMID:11390992

Numerical analysis of magnetically suspended rotor in HTR-10 helium circulator being dropped into auxiliary bearings

International Nuclear Information System (INIS)

Zhao Jingxiong; Yang Guojun; Li Yue; Yu Suyuan

2012-01-01

Active magnetic bearings (AMB) have been selected to support the rotor of primary helium circulator in commercial 10 Mega-Walt High Temperature Gas-cooled Reactor (HTR-10). In an AMB system, the auxiliary bearings are necessary to protect the AMB components in case of losing power. This paper performs the impact simulation of Magnetically Suspended Rotor in HTR-10 Helium Circulator being dropped into the auxiliary bearings using the finite element program ABAQUS. The dynamic response and the strain field of auxiliary bearings are analyzed. The results achieved by the numerical analysis are in agreement with the experiment results. Therefore, the feasibility of the design of auxiliary bearing and the possibility of using the AMB system in the HTR are proved. (authors)

Water chemistry control in HTTR

International Nuclear Information System (INIS)

Sekita, Kenji; Furusawa, Takayuki; Emori, Koichi; Kuroha, Misao; Hayakawa, Masato; Ohuchi, Hiroshi; Ishii, Taro

2008-08-01

A carbon steel is used for the main material for the components and pipings of the pressurized water cooling system etc. that are the reactor cooling system of the HTTR. Water quality is managed by using the hydrazine in the coolant of the water cooling system to prevent corrosion of the components and deoxidize the coolant. Also, regular analysis is carried out for the confirmation of the water quality. The following results were obtained through the water quality analysis. (1) In the pressurized water cooling system, the coolant temperature rises higher due to the heat removal of the primary coolant. So, the ammonia was formed in the thermal decomposition of the hydrazine. The electric conductivity increased, while the concentration of the hydrazine decreased, there was no problem as the plan it. (2) Thermal decomposition of the hydrazine was not occurred in the auxiliary water cooling system and vessel cooling system because of the coolant temperature was low. (3) An indistinct procedure is clarified and procedure of water quality analysis was established in the HTTR. (4) It is assumed that the corrosion of the components in these water cooling system hardly occurred from measurement results of dissolved oxide and chloride ion. Thus, the water quality was managed enough. (author)

ASCERTAINMENT OF ELECTRIC-SUPPLY SCHEMES RELIABILITY FOR THE ATOMIC POWER PLANT AUXILIARIES

Directory of Open Access Journals (Sweden)

A. L. Starzhinskij

2015-01-01

Full Text Available The paper completes ascertainment of electrical-supply scheme reliability for the auxiliaries of a nuclear power plant. Thereat the author considers the system behavior during the block normal operation, carrying out current maintenance, and capital repairs in combination with initiating events. The initiating events for reactors include complete blackout, i.e. the loss of outside power supply (normal and reserve; emergency switching one of the working turbogenerators; momentary dumping the normal rating to the level of auxiliaries with seating the cutout valve of one turbo-generator. The combination of any initiating event with the repairing mode in case of one of the system elements failure should not lead to blackout occurrence of more than one system of the reliable power supply. This requirement rests content with the help of the reliable power supply system self-dependence (electrical and functional and the emergency power-supply operational autonomy (diesel generator and accumulator batteries.The reliability indicators of the power supply system for the nuclear power plant auxiliaries are the conditional probabilities of conjoined blackout of one, two, and three sections of the reliable power supply conditional upon an initiating event emerging and the blackout of one, two, and three reliable power-supply sections under the normal operational mode. Furthermore, they also are the blackout periodicity of one and conjointly two, three, and four sections of normal operation under the block normal operational mode. It is established that the blackout of one bus section of normal operation and one section of reliable power-supply system of the auxiliaries that does not lead to complete blackout of the plant auxiliaries may occur once in three years. The probability of simultaneous power failure of two or three normal-operation sections and of two reliable power-supply sections during the power plant service life is unlikely.

The CFS-PML for 2D Auxiliary Differential Equation FDTD Method Using Associated Hermite Orthogonal Functions

Directory of Open Access Journals (Sweden)

Feng Jiang

2017-01-01

Full Text Available The complex frequency shifted (CFS perfectly matched layer (PML is proposed for the two-dimensional auxiliary differential equation (ADE finite-difference time-domain (FDTD method combined with Associated Hermite (AH orthogonal functions. According to the property of constitutive parameters of CFS-PML (CPML absorbing boundary conditions (ABCs, the auxiliary differential variables are introduced. And one relationship between field components and auxiliary differential variables is derived. Substituting auxiliary differential variables into CPML ABCs, the other relationship between field components and auxiliary differential variables is derived. Then the matrix equations are obtained, which can be unified with Berenger’s PML (BPML and free space. The electric field expansion coefficients can thus be obtained, respectively. In order to validate the efficiency of the proposed method, one example of wave propagation in two-dimensional free space is calculated using BPML, UPML, and CPML. Moreover, the absorbing effectiveness of the BPML, UPML, and CPML is discussed in a two-dimensional (2D case, and the numerical simulations verify the accuracy and efficiency of the proposed method.

Magnetic levitation and MHD propulsion

International Nuclear Information System (INIS)

Tixador, P.

1994-01-01

Magnetic levitation and MHD propulsion are now attracting attention in several countries. Different superconducting MagLev and MHD systems will be described concentrating on, above all, the electromagnetic aspect. Some programmes occurring throughout the world will be described. Magnetic levitated trains could be the new high speed transportation system for the 21st century. Intensive studies involving MagLev trains using superconductivity have been carried our in Japan since 1970. The construction of a 43 km long track is to be the next step. In 1991 a six year programme was launched in the United States to evaluate the performances of MagLev systems for transportation. The MHD (MagnetoHydroDynamic) offers some interesting advantages (efficiency, stealth characteristics, ..) for naval propulsion and increasing attention is being paid towards it nowadays. Japan is also up at the top with the tests of Yamato I, a 260 ton MHD propulsed ship. (orig.)

Magnetic levitation and MHD propulsion

Energy Technology Data Exchange (ETDEWEB)

Tixador, P [CNRS/CRTBT-LEG, 38 - Grenoble (France)

1994-04-01

Magnetic levitation and MHD propulsion are now attracting attention in several countries. Different superconducting MagLev and MHD systems will be described concentrating on, above all, the electromagnetic aspect. Some programmes occurring throughout the world will be described. Magnetic levitated trains could be the new high speed transportation system for the 21st century. Intensive studies involving MagLev trains using superconductivity have been carried our in Japan since 1970. The construction of a 43 km long track is to be the next step. In 1991 a six year programme was launched in the United States to evaluate the performances of MagLev systems for transportation. The MHD (MagnetoHydroDynamic) offers some interesting advantages (efficiency, stealth characteristics, ..) for naval propulsion and increasing attention is being paid towards it nowadays. Japan is also up at the top with the tests of Yamato I, a 260 ton MHD propulsed ship. (orig.).

Generic description of facilities at the shaft head (auxiliary entrance installations) of deep geological repositories

International Nuclear Information System (INIS)

2016-10-01

In a deep geological repository, the access structures function as the link between the surface and the installations and structures at the disposal level. In the planned implementation scenarios, at least two access structures will be in operation up to the time of closure of the repository. The radioactive waste will be transported via the main access from the surface to the disposal level during emplacement operations. For the construction and operation of a deep geological repository, additional access structures are required. These auxiliary accesses and the associated surface infrastructure (e.g. shaft head installations) form the subject of this report. To provide as broad and comprehensive a description as possible, seven types of auxiliary access facilities are defined; these are characterised in line with the current status of planning and their functions and impacts are described. During construction, operation and dismantling of auxiliary access facilities, the usual conventional safety measures (inter alia) have to be observed (e.g. groundwater protection, fire prevention, facility security, accident prevention). Regarding the 'Ordinance on Protection against Major Accidents' no large quantities of hazardous materials, i.e. above the corresponding threshold quantities, are to be expected in the auxiliary access facilities. Proper handling and compliance with applicable regulations in all phases will ensure no hazard to humans and the environment. As no handling of radioactive materials is foreseen in the auxiliary access facilities, and because exhaust air and waste water from the controlled zones of a repository will, in principle, be removed via the main access and not the auxiliary accesses, a safety-relevant emission of radioactive substances and transport of contaminated material can be ruled out for the auxiliary access facilities during both normal operation and also in the case of an accident. Based on the information presented in

STATIC TESTS OF UNCONVENTIONAL PROPULSION UNITS FOR ULTRALIGHT AIRPLANES

Directory of Open Access Journals (Sweden)

Martin Helmich

2014-06-01

Full Text Available This paper presents static tests of a new unconventional propulsion unit for small aviation airplanes. Our laboratory stand – a fan drive demonstrator – enables us to compare various design options. We performed experiments to verify the propulsion functionality and a measurement procedure to determine the available thrust of the propulsion unit and its dependence on engine speed. The results used for subsequent optimization include the operating parameters of the propulsion unit, and the temperature and velocity fields in parts of the air duct.

An Overview of the CNES Propulsion Program for Spacecraft

Science.gov (United States)

Cadiou, A.; Darnon, F.; Gibek, I.; Jolivet, L.; Pillet, N.

2004-10-01

This paper presents an overview of the CNES spacecraft propulsion activities. The main existing and future projects corresponding to low earth orbit and geostationary platforms are described. These projects cover various types of propulsion subsystems: monopropellant, bipropellant and electric. Monopropellant is mainly used for low earth orbit applications such as earth observation (SPOT/Helios, PLEIADES) or scientific applications (minisatellite PROTEUS line and micro satellites MYRIADE line). Bipropellant is used for geostationary telecommunications satellites (@BUS). The field of application of electric propulsion is the station keeping of geostationary telecommunication satellites (@BUS), main propulsion for specific probes (SMART 1) and fine attitude control for dedicated micro satellites (MICROSCOPE). The preparation of the future and the associated Research and Technology program are also described in the paper. The future developments are mainly dedicated to the performance improvements of electric propulsion which leads to the development of thrusters with higher thrust and higher specific impulse than those existing today, the evaluation of the different low thrust technologies for formation flying applications, the development of new systems to pressurize the propellants (volatile liquid, micro pump), the research on green propellants and different actions concerning components such as over wrapped pressure vessels, valves, micro propulsion. A constant effort is also put on plume effect in chemical and electrical propulsion area (improvement of tools and test activities) in the continuity of the previous work. These different R &T activities are described in detail after a presentation of the different projects and of their propulsion subsystems. The scientific activity supporting the development of Hall thrusters is going on in the frame of the GDR (Groupement de Recherche) CNRS / Universities / CNES / SNECMA on Plasma Propulsion.

A comparison of propulsion systems for potential space mission applications

International Nuclear Information System (INIS)

Harvego, E.A.; Sulmeisters, T.K.

1987-01-01

A derivative of the NERVA nuclear rocket engine was compared with a chemical propulsion system and a nuclear electric propulsion system to assess the relative capabilities of the different propulsion system options for three potential space missions. The missions considered were (1) orbital transfer from low earth orbit (LEO) to geosynchronous earth orbit (GEO), (2) LEO to a lunar base, and (3) LEO to Mars. The results of this comparison indicate that the direct-thrust NERVA-derivative nuclear rocket engine has the best performance characteristics for the missions considered. The combined high thrust and high specific impulse achievable with a direct-thrust nuclear stage permits short operating times (transfer times) comparable to chemical propulsion systems, but with considerably less required propellant. While nuclear-electric propulsion systems are more fuel efficient than either direct-nuclear or chemical propulsion, they are not stand-alone systems, since their relatively low thrust levels require the use of high-thrust ferry or lander stages in high gravity applications such as surface-to-orbit propulsion. The extremely long transfer times and inefficient trajectories associated with electric propulsion systems were also found to be a significant drawback

Research on applications of rectangular beam in micro laser propulsion

International Nuclear Information System (INIS)

Jiao, L.; Cai, J.; Ma, H.H.; Li, G.X.; Li, L.; Shen, Z.W.; Tang, Z.P.

2014-01-01

Highlights: • Diode laser bar of 808 nm is introduced into the micro laser propulsion field. • Double base propellant (DBP) coating with BOPP substrate was obtained. • The combination of laser power and energy decides the propulsion performance. • The new rectangular beam prefers to produce higher impulse. - Abstract: Micro laser propulsion is a new technology with brilliant future. In order to reduce the thruster mass and volume further, laser bar is introduced into the micro laser propulsion field. A new kind of 220 × 20 μm rectangular beam of 808 nm was obtained by oval lens compressing the light of diode at fast axes and slow axes. The effect of laser power, energy and coating thickness of double base propellant on propulsion performance was studied. Propulsion performance of double base propellant under static and dynamic mode shows some different characters. Compared to round beam, the new beam prefers to produce higher impulse. Ablation efficiency of DBP shows better performance in short laser duration. The combination of power density and energy density decides the laser propulsion performance. The new rectangular beam is appropriate for millisecond micro-laser propulsion

Vanishing auxiliary variables in PPS sampling - with applications in microscopy

DEFF Research Database (Denmark)

Andersen, Ina Trolle; Hahn, Ute; Jensen, Eva B. Vedel

Recently, non-uniform sampling has been suggested in microscopy to increase efficiency. More precisely, sampling proportional to size (PPS) has been introduced where the probability of sampling a unit in the population is proportional to the value of an auxiliary variable. Unfortunately, vanishing...... auxiliary variables are a common phenomenon in microscopy and, accordingly, part of the population is not accessible, using PPS sampling. We propose a modification of the design, for which an optimal solution can be found, using a model assisted approach. The optimal design has independent interest...... in sampling theory. We verify robustness of the new approach by numerical results, and we use real data to illustrate the applicability....

[The surgical nurse: his/her leadership of auxiliary nursing personnel].

Science.gov (United States)

Galvão, C M; Trevizan, M A; Sawada, N O; Mendes, I A

1997-01-01

This investigation as carried out in order to promote follow-up in the studies concerning nurse's leadership in the hospital context. Emphasys is given to the nurses that works in surgical ward unities. As a theoretical framework, authors utilized the model of leadership proposed by Hersey and Blanchard, named Situational Leadership. The objective was to analyze the correspondence of opinion between nurses and nursing auxiliary personnel about the leadership style of nurse should adopt in accordance with the maturity level of an element of the auxiliary personnel based on six categories of activities that were studied. Authors found out that nurses should adopt the styles of participant leadership, such as E3 (participating) and/or E4 (delegating).

The influence of verbal training and visual feedback on manual wheelchair propulsion.

Science.gov (United States)

DeGroot, Keri K; Hollingsworth, Holly H; Morgan, Kerri A; Morris, Carrie L; Gray, David B

2009-03-01

To determine if verbal training with visual feedback improved manual wheelchair propulsion; to examine propulsion differences between an individual with paraplegia and an individual with tetraplegia. Quasi-experimental study: Nine manual wheelchair-using adults participated in propulsion assessments and training. Baseline propulsion performance was measured on several tasks on different surfaces. Participants were trained on a wheelchair treadmill with verbal and visual feedback to increase push length, reduce push frequency and to modify propulsion pattern. Handrim biomechanics were measured with an instrumented wheel. Changes in propulsion were assessed. Differences in propulsion characteristics between a participant with paraplegia and a participant with tetraplegia were examined. Push length increased (p propulsion characteristics between a participant with paraplegia and a participant with tetraplegia. Verbal training may produce changes in push biomechanics of manual wheelchair users. Longer training periods may be needed to sustain propulsion changes. Findings from this study support other studies that have shown propulsion differences between people with tetraplegia and paraplegia. Propulsion training for populations with upper-extremity impairments warrants further study.

A new auxiliary equation and exact travelling wave solutions of nonlinear equations

International Nuclear Information System (INIS)

Sirendaoreji

2006-01-01

A new auxiliary ordinary differential equation and its solutions are used for constructing exact travelling wave solutions of nonlinear partial differential equations in a unified way. The main idea of this method is to take full advantage of the auxiliary equation which has more new exact solutions. More new exact travelling wave solutions are obtained for the quadratic nonlinear Klein-Gordon equation, the combined KdV and mKdV equation, the sine-Gordon equation and the Whitham-Broer-Kaup equations

Propulsion Electric Grid Simulator (PEGS) for Future Turboelectric Distributed Propulsion Aircraft

Science.gov (United States)

Choi, Benjamin B.; Morrison, Carlos; Dever, Timothy; Brown, Gerald V.

2014-01-01

NASA Glenn Research Center, in collaboration with the aerospace industry and academia, has begun the development of technology for a future hybrid-wing body electric airplane with a turboelectric distributed propulsion (TeDP) system. It is essential to design a subscale system to emulate the TeDP power grid, which would enable rapid analysis and demonstration of the proof-of-concept of the TeDP electrical system. This paper describes how small electrical machines with their controllers can emulate all the components in a TeDP power train. The whole system model in Matlab/Simulink was first developed and tested in simulation, and the simulation results showed that system dynamic characteristics could be implemented by using the closed-loop control of the electric motor drive systems. Then we designed a subscale experimental system to emulate the entire power system from the turbine engine to the propulsive fans. Firstly, we built a system to emulate a gas turbine engine driving a generator, consisting of two permanent magnet (PM) motors with brushless motor drives, coupled by a shaft. We programmed the first motor and its drive to mimic the speed-torque characteristic of the gas turbine engine, while the second motor and drive act as a generator and produce a torque load on the first motor. Secondly, we built another system of two PM motors and drives to emulate a motor driving a propulsive fan. We programmed the first motor and drive to emulate a wound-rotor synchronous motor. The propulsive fan was emulated by implementing fan maps and flight conditions into the fourth motor and drive, which produce a torque load on the driving motor. The stator of each PM motor is designed to travel axially to change the coupling between rotor and stator. This feature allows the PM motor to more closely emulate a wound-rotor synchronous machine. These techniques can convert the plain motor system into a unique TeDP power grid emulator that enables real-time simulation performance

PEGASUS: a multi-megawatt nuclear electric propulsion system

International Nuclear Information System (INIS)

Coomes, E.P.; Cuta, J.M.; Webb, B.J.; King, D.Q.

1985-06-01

With the Space Transportation System (STS), the advent of space station Columbus and the development of expertise at working in space that this will entail, the gateway is open to the final frontier. The exploration of this frontier is possible with state-of-the-art hydrogen/oxygen propulsion but would be greatly enhanced by the higher specific impulse of electric propulsion. This paper presents a concept that uses a multi-megawatt nuclear power plant to drive an electric propulsion system. The concept has been named PEGASUS, PowEr GenerAting System for Use in Space, and is intended as a ''work horse'' for general space transportation needs, both long- and short-haul missions. The recent efforts of the SP-100 program indicate that a power system capable of producing upwards of 1 megawatt of electric power should be available in the next decade. Additionally, efforts in other areas indicate that a power system with a constant power capability an order of magnitude greater could be available near the turn of the century. With the advances expected in megawatt-class space power systems, the high specific impulse propulsion systems must be reconsidered as potential propulsion systems. The power system is capable of meeting both the propulsion system and spacecraft power requirements

Propulsion Wheel Motor for an Electric Vehicle

Science.gov (United States)

Figuered, Joshua M. (Inventor); Herrera, Eduardo (Inventor); Waligora, Thomas M. (Inventor); Bluethmann, William J. (Inventor); Farrell, Logan Christopher (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Winn, Ross Briant (Inventor); Eggleston, IV, Raymond Edward (Inventor); Guo, Raymond (Inventor);

Performance assessment of auxiliary bearing in HTR-10 AMB helium circulator on the event of rotor drop

International Nuclear Information System (INIS)

Xiao Zhen; Yang Guojun; Li Yue; Shi Zhengang; Yu Suyuan

2014-01-01

In this paper, a model for analyzing internal contact stress arid external load of ball bearing from rotor displacement was developed based on the Hertz contact theory and applied to the analysis of the rotor drop test in HTR-10 helium circulator equipped with AMB (Active Magnetic Bearing) to gain a better understanding of auxiliary bearing performance at different stages after the rotor drop. It was shown that the auxiliary bearing can well resist axial impact produced by rotor drop, avoiding of internal severe plastic deformation and damage to the performance of the auxiliary bearing. Rotor's rotary motion and the heat accumulation of the inner ring resulted from the initial acute acceleration are the main contributor of radial load during the rotor idling and may cause the failure of auxiliary bearing. This paper analyzed the influence of this load and confirmed that the auxiliary bearing can still work in its loading limits. (authors)

Study of underwater laser propulsion using different target materials.

Science.gov (United States)

Qiang, Hao; Chen, Jun; Han, Bing; Shen, Zhong-Hua; Lu, Jian; Ni, Xiao-Wu

2014-07-14

In order to investigate the influence of target materials, including aluminum (Al), titanium (Ti) and copper (Cu), on underwater laser propulsion, the analytical formula of the target momentum IT is deduced from the enhanced coupling theory of laser propulsion in atmosphere with transparent overlay metal target. The high-speed photography method and numerical simulation are employed to verify the IT model. It is shown that the enhanced coupling theory, which was developed originally for laser propulsion in atmosphere, is also applicable to underwater laser propulsion with metal targets.

Auxiliary fields for super Yang-Mills from division algebras

CERN Document Server

Evans, Jonathan M.

1994-01-01

Division algebras are used to explain the existence and symmetries of various sets of auxiliary fields for super Yang-Mills in dimensions d=3,4,6,10. (Contribution to G\\"ursey Memorial Conference I: Strings and Symmetries)

Cobalt nanoparticles as sacrificial templates for the electrodeposition of palladium nanomaterials in an ionic liquid, and its application to electrochemical sensing of hydrazine

International Nuclear Information System (INIS)

He, Y.; Zheng, J.; Sheng, Q.

2012-01-01

We report on the electrodeposition of palladium nanomaterials in choline chloride-based ionic liquid ethaline. A glassy carbon electrode (GCE) was modified with cobalt nanoparticles (acting as sacrificial templates) and a GCE modified with palladium nanoparticles (PdNPs) were fabricated and used to study the electrocatalytic oxidation of hydrazine (N 2 H 4 ). Scanning electron microscopy revealed that the PdNP modified GCE has a uniform morphology. Zero current potentiometry was used for in-situ probing the changes in interfacial potential of the oxidation of hydrazine. An amperometric study showed that the PdNP modified GCE possesses excellent electrocatalytic activity towards N 2 H 4 . The modified electrode displays a fast response ( -1 ) -1 cm -2 ) and broad linearity in the range from 0.1 to 800 μmol L -1 with a detection limit of 0.03 μmol L -1 (S/N = 3). (author)

Mars Sample Return Using Solar Sail Propulsion

Science.gov (United States)

Johnson, Les; Macdonald, Malcolm; Mcinnes, Colin; Percy, Tom

2012-01-01

Many Mars Sample Return (MSR) architecture studies have been conducted over the years. A key element of them is the Earth Return Stage (ERS) whose objective is to obtain the sample from the Mars Ascent Vehicle (MAV) and return it safely to the surface of the Earth. ERS designs predominantly use chemical propulsion [1], incurring a significant launch mass penalty due to the low specific impulse of such systems coupled with the launch mass sensitivity to returned mass. It is proposed to use solar sail propulsion for the ERS, providing a high (effective) specific impulse propulsion system in the final stage of the multi-stage system. By doing so to the launch mass of the orbiter mission can be significantly reduced and hence potentially decreasing mission cost. Further, solar sailing offers a unique set of non-Keplerian low thrust trajectories that may enable modifications to the current approach to designing the Earth Entry Vehicle by potentially reducing the Earth arrival velocity. This modification will further decrease the mass of the orbiter system. Solar sail propulsion uses sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like surface made of a lightweight, reflective material. The continuous photonic pressure provides propellantless thrust to conduct orbital maneuvering and plane changes more efficiently than conventional chemical propulsion. Because the Sun supplies the necessary propulsive energy, solar sails require no onboard propellant, thus reducing system mass. This technology is currently at TRL 7/8 as demonstrated by the 2010 flight of the Japanese Aerospace Exploration Agency, JAXA, IKAROS mission. [2

DISCRETION MAGNETIQUE DES MACHINES ELECTRIQUES DE PROPULSION NAVALE

OpenAIRE

Froidurot , Benoît

2002-01-01

For about ten years, electrical machines have been commonly used in naval propulsion systems for civilian applications. This is mainly due to new magnetic materials (magnets...) and power drive electronic, which increase the performances of the machines. This kind of propulsion is planed to be implemented on military ships. However, some constraints of discretion make this propulsion require specific systems for the ship security. This study is then dedicted to the magnetic discretion of nava...

Children's Gender-Typed Toy Interests: Does Propulsion Matter?

Science.gov (United States)

Dinella, Lisa M; Weisgram, Erica S; Fulcher, Megan

2017-07-01

Children's toy play is at the foundation of child development. However, gender differentiation in early play experiences may result in gender differences in cognitive abilities, social interactions, and vocational choices. We investigated gender-typing of toys and toys' propulsive properties (e.g., wheels, forward motion) as possible factors impacting children's toy interests, perceptions of other children's interests, and children's actual toy choices during free play. In Studies 1 and 2, 82 preschool children (42 boys, 40 girls; mean age = 4.90 years) were asked to report their interest and perceptions of other children's interests in toys. In Study 1, masculine, feminine, and neutral toys with and without propulsive properties were presented. Children reported greater interest in gender-typed toys and neutral toys compared to cross-gender-typed toys. In Study 2, unfamiliar, neutral toys with and without propulsive properties were presented. Propulsive properties did not affect children's interest across both studies. Study 3 was an observational study that assessed toy preferences among 42 preschool children (21 males, 21 females, mean age = 4.49 years) during a play session with masculine, feminine, and neutral toys with and without propulsive properties. Gender-typed toy preferences were less apparent than expected, with children showing high interest in neutral toys, and girls playing with a wide variety of masculine, feminine, and neutral toys. Gender differences in interest for toys with propulsion properties were not evident. Overall, gender differences in children's interest in toys as a function of propulsion properties were not found in the three experiments within this study.

The Enabling Use of Ion Propulsion on Dawn

Science.gov (United States)

Rayman, M.; Russell, C. T.; Raymond, C. A.; Mase, R. M.

2011-12-01

Dawn's mission to orbit both Vesta and Ceres is enabled by its use of ion propulsion. Even orbiting Vesta alone with conventional propulsion would have been unaffordable within the constraints of the Discovery Program, and orbiting both would have been impossible. In fact, no other spacecraft has been targeted to orbit two solar system destinations, which is only one of the many firsts that Dawn will achieve. The successful testing of ion propulsion on Deep Space 1 paved the way for Dawn not only to use the hardware with confidence but also to learn how to design the flight system and design the mission to take advantage of its capabilities. In addition to allowing Dawn to reach these two important targets, ion propulsion allows the spacecraft to accomplish significant changes in its orbit. Therefore, science observations of Vesta are planned from four different orbits, at varying altitudes and solar geometry. The use of ion propulsion results in a significant mission design effort since the trajectory is constantly being refined. This also creates a flexible mission architecture, which allows for optimization of the mission as conditions change. Solar electric ion propulsion is especially well suited to missions to the Main Asteroid Belt since solar energy is still a viable power source, whereas the size of the solar array needed beyond 3.5 AU is a potential limitation. Dawn has already surpassed the record for greatest propulsive velocity, but its greatest achievements will no doubt be the incredible bounty of science data enabled by this innovative flight system.

A two-dimensional ZnII coordination polymer constructed from benzene-1,2,3-tricarboxylic acid and N,N'-bis[(pyridin-4-yl)methylidene]hydrazine.

Science.gov (United States)

Wang, Xiangfei; Yang, Fang; Tang, Meng; Yuan, Limin; Liu, Wenlong

2015-07-01

The hydrothermal synthesis of the novel complex poly[aqua(μ4-benzene-1,2,3-tricarboxylato)[μ2-4,4'-(hydrazine-1,2-diylidenedimethanylylidene)dipyridine](μ3-hydroxido)dizinc(II)], [Zn(C9H3O6)(OH)(C12H10N4)(H2O)]n, is described. The benzene-1,2,3-tricarboxylate ligand connects neighbouring Zn4(OH)2 secondary building units (SBUs) producing an infinite one-dimensional chain. Adjacent one-dimensional chains are connected by the N,N'-bis[(pyridin-4-yl)methylidene]hydrazine ligand, forming a two-dimensional layered structure. Adjacent layers are stacked to generate a three-dimensional supramolecular architecture via O-H...O hydrogen-bond interactions. The thermal stability of this complex is described and the complex also appears to have potential for application as a luminescent material.

Contributions of nonextracting Pu reductants (ferrous sulphamate and hydroxylamine nitrate) and holding reductant (hydrazine nitrate) to the aqueous density in U-Pu partitioning system

International Nuclear Information System (INIS)

Shekhar Kumar; Rajnish Kumar; Koganti, S.B.

2005-08-01

As nonextracting Pu reductants and holding reductants contribute to the density of aqueous phase sub-system considerably, to account their contributions in aqueous phase in solvent extraction simulation code is essential. In this regard, in-house generated precise density data on aqueous ferrous sulphamate solutions as well as aqueous density data, reported in the literature, for HAN, hydrazine nitrate and HAN-HNO 3 systems were analyzed and density equation earlier proposed by authors was extended to it. It was observed that the equation earlier proposed by the authors were simple and were easy to extend for multicomponent system. The contributions of ferrous sulphamate, HAN and hydrazine nitrate to the aqueous density were quantified. It was also observed that the classical value of contribution for nonextractible solute to the aqueous density was quite different from the results reported in this work. (author)

ADAPTIVE SELECTION OF AUXILIARY OBJECTIVES IN MULTIOBJECTIVE EVOLUTIONARY ALGORITHMS

Directory of Open Access Journals (Sweden)

I. A. Petrova

2016-05-01

Full Text Available Subject of Research.We propose to modify the EA+RL method, which increases efficiency of evolutionary algorithms by means of auxiliary objectives. The proposed modification is compared to the existing objective selection methods on the example of travelling salesman problem. Method. In the EA+RL method a reinforcement learning algorithm is used to select an objective – the target objective or one of the auxiliary objectives – at each iteration of the single-objective evolutionary algorithm.The proposed modification of the EA+RL method adopts this approach for the usage with a multiobjective evolutionary algorithm. As opposed to theEA+RL method, in this modification one of the auxiliary objectives is selected by reinforcement learning and optimized together with the target objective at each step of the multiobjective evolutionary algorithm. Main Results.The proposed modification of the EA+RL method was compared to the existing objective selection methods on the example of travelling salesman problem. In the EA+RL method and its proposed modification reinforcement learning algorithms for stationary and non-stationary environment were used. The proposed modification of the EA+RL method applied with reinforcement learning for non-stationary environment outperformed the considered objective selection algorithms on the most problem instances. Practical Significance. The proposed approach increases efficiency of evolutionary algorithms, which may be used for solving discrete NP-hard optimization problems. They are, in particular, combinatorial path search problems and scheduling problems.

Space station propulsion requirements study

Science.gov (United States)

Wilkinson, C. L.; Brennan, S. M.

1985-01-01

Propulsion system requirements to support Low Earth Orbit (LEO) manned space station development and evolution over a wide range of potential capabilities and for a variety of STS servicing and space station operating strategies are described. The term space station and the overall space station configuration refers, for the purpose of this report, to a group of potential LEO spacecraft that support the overall space station mission. The group consisted of the central space station at 28.5 deg or 90 deg inclinations, unmanned free-flying spacecraft that are both tethered and untethered, a short-range servicing vehicle, and a longer range servicing vehicle capable of GEO payload transfer. The time phasing for preferred propulsion technology approaches is also investigated, as well as the high-leverage, state-of-the-art advancements needed, and the qualitative and quantitative benefits of these advancements on STS/space station operations. The time frame of propulsion technologies applicable to this study is the early 1990's to approximately the year 2000.

The gamma-ray induced chemisorption of oxygen on perovskite type catalysts: determination by reduction with hydrazine sulphate/hydroxylamine hydrochloride

International Nuclear Information System (INIS)

Srinivas, B.; Rao, V.R.S.; Kuriacose, J.C.

1986-01-01

Chemisorbed oxygen can be determined quantitatively by the measurement of gaseous N 2 /N 2 O liberated by treatment with hydrazine sulfate/hydroxylamine hydrochloride. The amount of chemisorbed oxygen depends on the degree of dispersion during irradiation and also on the γ-dose. The chemisorption is enhanced in the presence of moisture. The partial reduction of the transition metal ion favours the formation of chemisorbed oxygen. (author)

NASA program planning on nuclear electric propulsion

International Nuclear Information System (INIS)

Bennett, G.L.; Miller, T.J.

1992-03-01

As part of the focused technology planning for future NASA space science and exploration missions, NASA has initiated a focused technology program to develop the technologies for nuclear electric propulsion and nuclear thermal propulsion. Beginning in 1990, NASA began a series of interagency planning workshops and meetings to identify key technologies and program priorities for nuclear propulsion. The high-priority, near-term technologies that must be developed to make NEP operational for space exploration include scaling thrusters to higher power, developing high-temperature power processing units, and developing high power, low-mass, long-lived nuclear reactors. 28 refs

Definition of an arcjet propulsion sub-system

International Nuclear Information System (INIS)

Price, T.W.

1989-01-01

An engineering flight demonstration of a 100 kW3 Space Reactor Power System is planned for the mid to late 1990s. An arcjet based propulsion subsystem will be included on the flight demonstraction as a secondary experiment. Two studies, sponsored by the Kay Technologies Directorate of the SDI Organization and managed by the Jet Propulsion Laboratory are currently under way to define that propulsion subsystem. The principal tasks of those contracts and the plans for two later phases, an experimental verification of the concept and a flight qualification/delivery of a flight unit, are described. 9 refs

Loss mechanisms in hydrazine-processed Cu2ZnSn(Se,S)4 solar cells

Science.gov (United States)

Gunawan, Oki; Todorov, Teodor K.; Mitzi, David B.

2010-12-01

We present a device characterization study for hydrazine-processed kesterite Cu2ZnSn(Se,S)4 (CZTSSe) solar cells with a focus on pinpointing the main loss mechanisms limiting device efficiency. Temperature-dependent study and time-resolved photoluminescence spectroscopy on these cells, in comparison to analogous studies on a reference Cu(In,Ga)(Se,S)2 (CIGS) cell, reveal strong recombination loss at the CZTSSe/CdS interface, very low minority-carrier lifetimes, and high series resistance that diverges at low temperature. These findings help identify the key areas for improvement of these CZTSSe cells in the quest for a high-performance indium- and tellurium-free solar cell.

Hydrogenation of liquid natural rubber via diimide reduction in hydrazine hydrate/hydrogen peroxide system

International Nuclear Information System (INIS)

Yusof, Muhammad Jefri Mohd; Jamaluddin, Naharullah; Abdullah, Ibrahim; Yusoff, Siti Fairus M.

2015-01-01

Liquid natural rubber (LNR) with molecular weight of lower than 10 5 and shorter polymeric chain than natural rubber was prepared. LNR was then hydrogenated via diimide reduction by oxidation of hydrazine hydrate with hydrogen peroxide. The unsaturated units of the rubber were converted into saturated hydrocarbon to strengthen the backbone of the polymer so it was able to resist thermal degradation. The results indicated that hydrogenation degree of the product (HLNR) could be extended to 91.2% conversion under appropriate conditions. The hydrogenated LNR (HLNR) was characterized using Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. The physical characteristics of HLNR were analyzed with Termogravimetric Analysis (TGA)

Hydrogenation of liquid natural rubber via diimide reduction in hydrazine hydrate/hydrogen peroxide system

Science.gov (United States)

Yusof, Muhammad Jefri Mohd; Jamaluddin, Naharullah; Abdullah, Ibrahim; Yusoff, Siti Fairus M.

2015-09-01

Liquid natural rubber (LNR) with molecular weight of lower than 105 and shorter polymeric chain than natural rubber was prepared. LNR was then hydrogenated via diimide reduction by oxidation of hydrazine hydrate with hydrogen peroxide. The unsaturated units of the rubber were converted into saturated hydrocarbon to strengthen the backbone of the polymer so it was able to resist thermal degradation. The results indicated that hydrogenation degree of the product (HLNR) could be extended to 91.2% conversion under appropriate conditions. The hydrogenated LNR (HLNR) was characterized using Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. The physical characteristics of HLNR were analyzed with Termogravimetric Analysis (TGA).

Hydrogenation of liquid natural rubber via diimide reduction in hydrazine hydrate/hydrogen peroxide system

Energy Technology Data Exchange (ETDEWEB)

Yusof, Muhammad Jefri Mohd; Jamaluddin, Naharullah; Abdullah, Ibrahim; Yusoff, Siti Fairus M. [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

2015-09-25

Liquid natural rubber (LNR) with molecular weight of lower than 10{sup 5} and shorter polymeric chain than natural rubber was prepared. LNR was then hydrogenated via diimide reduction by oxidation of hydrazine hydrate with hydrogen peroxide. The unsaturated units of the rubber were converted into saturated hydrocarbon to strengthen the backbone of the polymer so it was able to resist thermal degradation. The results indicated that hydrogenation degree of the product (HLNR) could be extended to 91.2% conversion under appropriate conditions. The hydrogenated LNR (HLNR) was characterized using Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. The physical characteristics of HLNR were analyzed with Termogravimetric Analysis (TGA)

28th Joint Propulsion Conference and Exhibit

International Nuclear Information System (INIS)

Stone, J.R.; Sovey, J.S.

1992-07-01

The National Aeronautics and Space Administration (NASA) has initiated a program to establish the readiness of nuclear electric propulsion (NEP) technology for relatively near-term applications to outer planet robotic science missions with potential future evolution to system for piloted Mars vehicles. This program was initiated in 1991 with a very modest effort identified with nuclear thermal propulsion (NTP); however, NEP is also an integral part of this program and builds upon NASA's Base Research and Technology Program in power and electric propulsion as well as the SP-100 space nuclear power program. The NEP Program will establish the feasibility and practicality of electric propulsion for robotic and piloted solar system exploration. The performance objectives are high specific impulse (200 greater than I(sub sp) greater than 10000 s), high efficiency (over 0.50), and low specific mass. The planning for this program was initially focussed on piloted Mars missions, but has since been redirected to first focus on 100-kW class systems for relatively near-term robotic missions, with possible future evolution to megawatt- and multi-megawatt-class systems applicable to cargo vehicles supporting human missions as well as to the piloted vehicles. This paper reviews current plans and recent progress for the overall nuclear electric propulsion project and closely related activities

Nuclear thermal propulsion engine cost trade studies

International Nuclear Information System (INIS)

Paschall, R.K.

1993-01-01

The NASA transportation strategy for the Mars Exploration architecture includes the use of nuclear thermal propulsion as the primary propulsion system for Mars transits. It is anticipated that the outgrowth of the NERVA/ROVER programs will be a nuclear thermal propulsion (NTP) system capable of providing the propulsion for missions to Mars. The specific impulse (Isp) for such a system is expected to be in the 870 s range. Trade studies were conducted to investigate whether or not it may be cost effective to invest in a higher performance (Isp>870 s) engine for nuclear thermal propulsion for missions to Mars. The basic cost trades revolved around the amount of mass that must be transported to low-earth orbit prior to each Mars flight and the cost to launch that mass. The mass required depended on the assumptions made for Mars missions scenarios including piloted/cargo flights, number of Mars missions, and transit time to Mars. Cost parameters included launch cost, program schedule for development and operations, and net discount rate. The results were very dependent on the assumptions that were made. Under some assumptions, higher performance engines showed cost savings in the billions of dollars; under other assumptions, the additional cost to develop higher performance engines was not justified

Status and Mission Applicability of NASA's In-Space Propulsion Technology Project

Science.gov (United States)

Anderson, David J.; Munk, Michelle M.; Dankanich, John; Pencil, Eric; Liou, Larry

2009-01-01

The In-Space Propulsion Technology (ISPT) project develops propulsion technologies that will enable or enhance NASA robotic science missions. Since 2001, the ISPT project developed and delivered products to assist technology infusion and quantify mission applicability and benefits through mission analysis and tools. These in-space propulsion technologies are applicable, and potentially enabling for flagship destinations currently under evaluation, as well as having broad applicability to future Discovery and New Frontiers mission solicitations. This paper provides status of the technology development, near-term mission benefits, applicability, and availability of in-space propulsion technologies in the areas of advanced chemical thrusters, electric propulsion, aerocapture, and systems analysis tools. The current chemical propulsion investment is on the high-temperature Advanced Material Bipropellant Rocket (AMBR) engine providing higher performance for lower cost. Investments in electric propulsion technologies focused on completing NASA's Evolutionary Xenon Thruster (NEXT) ion propulsion system, a 0.6-7 kW throttle-able gridded ion system, and the High Voltage Hall Accelerator (HiVHAC) thruster, which is a mid-term product specifically designed for a low-cost electric propulsion option. Aerocapture investments developed a family of thermal protections system materials and structures; guidance, navigation, and control models of blunt-body rigid aeroshells; atmospheric models for Earth, Titan, Mars and Venus; and models for aerothermal effects. In 2009 ISPT started the development of propulsion technologies that would enable future sample return missions. The paper describes the ISPT project's future focus on propulsion for sample return missions. The future technology development areas for ISPT is: Planetary Ascent Vehicles (PAV), with a Mars Ascent Vehicle (MAV) being the initial development focus; multi-mission technologies for Earth Entry Vehicles (MMEEV) needed

Laser Propulsion - Is it another myth or a real potential?

International Nuclear Information System (INIS)

Cook, Joung R.

2008-01-01

This paper discusses different principles of inducing propulsive power using lasers and examines the performance limits along with pros and cons with respect to different space propulsion applications: satellite launching, orbital transfer, space debris clearing, satellite propulsion, and space travels. It concludes that a use of electrical propulsion, in conjunction with laser power beaming, is the most feasible application with technological and economic advantages for commercial use within the next decades

FY2015 Propulsion Materials Annual Report

Energy Technology Data Exchange (ETDEWEB)

None, None

2016-12-30

The Propulsion Materials Program actively supports the energy security and reduction of greenhouse emissions goals of VTO by investigating and identifying the materials properties that are most essential for continued development of cost-effective, highly efficient, and environmentally friendly next-generation heavy and light-duty powertrains. The technical approaches available to enhance propulsion systems focus on improvements in both vehicle efficiency and fuel substitution, both of which must overcome the performance limitations of the materials currently in use. Propulsion Materials Program activities work with national laboratories, industry experts, and VTO powertrain systems (e.g., Advanced Combustion Engines [ACE], Advanced Power Electronics and Electrical Machines [APEEM], and fuels) teams to develop strategies that overcome materials limitations in future powertrain performance. The technical maturity of the portfolio of funded projects ranges from basic science to subsystem prototype validation. Projects within a Propulsion Materials Program activity address materials concerns that directly impact critical technology barriers within each of the above programs, including barriers that impact fuel efficiency, thermal management, emissions reduction, improved reliability, and reduced manufacturing costs. The program engages only the barriers that result from material property limitations and represent fundamental, high-risk materials issues.

Advanced propulsion system for hybrid vehicles

Science.gov (United States)

Norrup, L. V.; Lintz, A. T.

1980-01-01

A number of hybrid propulsion systems were evaluated for application in several different vehicle sizes. A conceptual design was prepared for the most promising configuration. Various system configurations were parametrically evaluated and compared, design tradeoffs performed, and a conceptual design produced. Fifteen vehicle/propulsion systems concepts were parametrically evaluated to select two systems and one vehicle for detailed design tradeoff studies. A single hybrid propulsion system concept and vehicle (five passenger family sedan)were selected for optimization based on the results of the tradeoff studies. The final propulsion system consists of a 65 kW spark-ignition heat engine, a mechanical continuously variable traction transmission, a 20 kW permanent magnet axial-gap traction motor, a variable frequency inverter, a 386 kg lead-acid improved state-of-the-art battery, and a transaxle. The system was configured with a parallel power path between the heat engine and battery. It has two automatic operational modes: electric mode and heat engine mode. Power is always shared between the heat engine and battery during acceleration periods. In both modes, regenerative braking energy is absorbed by the battery.

Measurement Issues In Pulsed Laser Propulsion

International Nuclear Information System (INIS)

Sinko, John E.; Scharring, Stefan; Eckel, Hans-Albert; Roeser, Hans-Peter; Sasoh, Akihiro

2010-01-01

Various measurement techniques have been used throughout the over 40-year history of laser propulsion. Often, these approaches suffered from inconsistencies in definitions of the key parameters that define the physics of laser ablation impulse generation. Such parameters include, but are not limited to the pulse energy, spot area, imparted impulse, and ablated mass. The limits and characteristics of common measurement techniques in each of these areas will be explored as they relate to laser propulsion. The idea of establishing some standardization system for laser propulsion data is introduced in this paper, so that reported results may be considered and studied by the general community with more certain understanding of particular merits and limitations. In particular, it is the intention to propose a minimum set of requirements a literature study should meet. Some international standards for measurements are already published, but modifications or revisions of such standards may be necessary for application to laser ablation propulsion. Issues relating to development of standards will be discussed, as well as some examples of specific experimental circumstances in which standardization would have prevented misinterpretation or misuse of past data.

Multireference Density Functional Theory with Generalized Auxiliary Systems for Ground and Excited States.

Science.gov (United States)

Chen, Zehua; Zhang, Du; Jin, Ye; Yang, Yang; Su, Neil Qiang; Yang, Weitao

2017-09-21

To describe static correlation, we develop a new approach to density functional theory (DFT), which uses a generalized auxiliary system that is of a different symmetry, such as particle number or spin, from that of the physical system. The total energy of the physical system consists of two parts: the energy of the auxiliary system, which is determined with a chosen density functional approximation (DFA), and the excitation energy from an approximate linear response theory that restores the symmetry to that of the physical system, thus rigorously leading to a multideterminant description of the physical system. The electron density of the physical system is different from that of the auxiliary system and is uniquely determined from the functional derivative of the total energy with respect to the external potential. Our energy functional is thus an implicit functional of the physical system density, but an explicit functional of the auxiliary system density. We show that the total energy minimum and stationary states, describing the ground and excited states of the physical system, can be obtained by a self-consistent optimization with respect to the explicit variable, the generalized Kohn-Sham noninteracting density matrix. We have developed the generalized optimized effective potential method for the self-consistent optimization. Among options of the auxiliary system and the associated linear response theory, reformulated versions of the particle-particle random phase approximation (pp-RPA) and the spin-flip time-dependent density functional theory (SF-TDDFT) are selected for illustration of principle. Numerical results show that our multireference DFT successfully describes static correlation in bond dissociation and double bond rotation.

Advanced supersonic propulsion study. [with emphasis on noise level reduction

Science.gov (United States)

Sabatella, J. A. (Editor)

1974-01-01

A study was conducted to determine the promising propulsion systems for advanced supersonic transport application, and to identify the critical propulsion technology requirements. It is shown that noise constraints have a major effect on the selection of the various engine types and cycle parameters. Several promising advanced propulsion systems were identified which show the potential of achieving lower levels of sideline jet noise than the first generation supersonic transport systems. The non-afterburning turbojet engine, utilizing a very high level of jet suppression, shows the potential to achieve FAR 36 noise level. The duct-heating turbofan with a low level of jet suppression is the most attractive engine for noise levels from FAR 36 to FAR 36 minus 5 EPNdb, and some series/parallel variable cycle engines show the potential of achieving noise levels down to FAR 36 minus 10 EPNdb with moderate additional penalty. The study also shows that an advanced supersonic commercial transport would benefit appreciably from advanced propulsion technology. The critical propulsion technology needed for a viable supersonic propulsion system, and the required specific propulsion technology programs are outlined.

Evaluation of advanced propulsion options for the next manned transportation system: Propulsion evolution study

Science.gov (United States)

Spears, L. T.; Kramer, R. D.

1990-01-01

The objectives were to examine launch vehicle applications and propulsion requirements for potential future manned space transportation systems and to support planning toward the evolution of Space Shuttle Main Engine (SSME) and Space Transportation Main Engine (STME) engines beyond their current or initial launch vehicle applications. As a basis for examinations of potential future manned launch vehicle applications, we used three classes of manned space transportation concepts currently under study: Space Transportation System Evolution, Personal Launch System (PLS), and Advanced Manned Launch System (AMLS). Tasks included studies of launch vehicle applications and requirements for hydrogen-oxygen rocket engines; the development of suggestions for STME engine evolution beyond the mid-1990's; the development of suggestions for STME evolution beyond the Advanced Launch System (ALS) application; the study of booster propulsion options, including LOX-Hydrocarbon options; the analysis of the prospects and requirements for utilization of a single engine configuration over the full range of vehicle applications, including manned vehicles plus ALS and Shuttle C; and a brief review of on-going and planned LOX-Hydrogen propulsion technology activities.

Distributed Multi-propulsion Units System

OpenAIRE

原田, 正志; HARADA, Masashi

2002-01-01

Reduction of the weight of the propulsion system is important in the design of a stratospheric airship. However, it also important to increaseefficiency of the system because available energy generated by solar cells on the hull is quite limited. One solution to increase efficiency of the propulsion system is to use a stern propeller, the propeller mounted on the stern of the hull as shown in Figure 1. Mounted on the stern of the hull, the stern propeller is merged with the boundary layer of ...

Model predictions for auxiliary heating in spheromaks

International Nuclear Information System (INIS)

Fauler, T.K.; Khua, D.D.

1997-01-01

Calculations are presented of the plasma temperature waited for under auxiliary heating in spheromaks. A model, ensuring good agreement of earlier experiments with joule heating results, is used. The model includes heat losses due to magnetic fluctuations and shows that the plasma temperatures of the kilo-electron-volt order may be achieved in a small device with the radius of 0.3 m only

Propulsion and Power Technologies for the NASA Exploration Vision: A Research Perspective

Science.gov (United States)

Litchford, Ron J.

2004-01-01

Future propulsion and power technologies for deep space missions are profiled in this viewgraph presentation. The presentation includes diagrams illustrating possible future travel times to other planets in the solar system. The propulsion technologies researched at Marshall Space Flight Center (MSFC) include: 1) Chemical Propulsion; 2) Nuclear Propulsion; 3) Electric and Plasma Propulsion; 4) Energetics. The presentation contains additional information about these technologies, as well as space reactors, reactor simulation, and the Propulsion Research Laboratory (PRL) at MSFC.

Hybrid Electric Propulsion Technologies for Commercial Transports

Science.gov (United States)

Bowman, Cheryl; Jansen, Ralph; Jankovsky, Amy

2016-01-01

NASA Aeronautics Research Mission Directorate has set strategic research thrusts to address the major drivers of aviation such as growth in demand for high-speed mobility, addressing global climate and capitalizing in the convergence of technological advances. Transitioning aviation to low carbon propulsion is one of the key strategic research thrust and drives the search for alternative and greener propulsion system for advanced aircraft configurations. This work requires multidisciplinary skills coming from multiple entities. The Hybrid Gas-Electric Subproject in the Advanced Air Transportation Project is energizing the transport class landscape by accepting the technical challenge of identifying and validating a transport class aircraft with net benefit from hybrid propulsion. This highly integrated aircraft of the future will only happen if airframe expertise from NASA Langley, modeling and simulation expertise from NASA Ames, propulsion expertise from NASA Glenn, and the flight research capabilities from NASA Armstrong are brought together to leverage the rich capabilities of U.S. Industry and Academia.