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Sample records for composite solid propellants

  1. High burn rate solid composite propellants

    Science.gov (United States)

    Manship, Timothy D.

    High burn rate propellants help maintain high levels of thrust without requiring complex, high surface area grain geometries. Utilizing high burn rate propellants allows for simplified grain geometries that not only make production of the grains easier, but the simplified grains tend to have better mechanical strength, which is important in missiles undergoing high-g accelerations. Additionally, high burn rate propellants allow for a higher volumetric loading which reduces the overall missile's size and weight. The purpose of this study is to present methods of achieving a high burn rate propellant and to develop a composite propellant formulation that burns at 1.5 inches per second at 1000 psia. In this study, several means of achieving a high burn rate propellant were presented. In addition, several candidate approaches were evaluated using the Kepner-Tregoe method with hydroxyl terminated polybutadiene (HTPB)-based propellants using burn rate modifiers and dicyclopentadiene (DCPD)-based propellants being selected for further evaluation. Propellants with varying levels of nano-aluminum, nano-iron oxide, FeBTA, and overall solids loading were produced using the HTPB binder and evaluated in order to determine the effect the various ingredients have on the burn rate and to find a formulation that provides the burn rate desired. Experiments were conducted to compare the burn rates of propellants using the binders HTPB and DCPD. The DCPD formulation matched that of the baseline HTPB mix. Finally, GAP-plasticized DCPD gumstock dogbones were attempted to be made for mechanical evaluation. Results from the study show that nano-additives have a substantial effect on propellant burn rate with nano-iron oxide having the largest influence. Of the formulations tested, the highest burn rate was a 84% solids loading mix using nano-aluminum nano-iron oxide, and ammonium perchlorate in a 3:1(20 micron: 200 micron) ratio which achieved a burn rate of 1.2 inches per second at 1000

  2. Manganese oxalate nanorods as ballistic modifier for composite solid propellants

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Supriya [Department of Chemistry, DDU Gorakhpur University, Gorakhpur 273009, U.P. (India); Chawla, Mohit [School of Basic Sciences, Indian Institute of Technology Mandi, Mandi 175005, H.P. (India); Siril, Prem Felix, E-mail: prem@iitmandi.ac.in [School of Basic Sciences, Indian Institute of Technology Mandi, Mandi 175005, H.P. (India); Singh, Gurdip [Department of Chemistry, DDU Gorakhpur University, Gorakhpur 273009, U.P. (India)

    2014-12-10

    Highlights: • Manganese oxalate nanorods were prepared using mild thermal precipitation and aging. • The nanorods were found to be efficient ballistic modifier for solid propellants. • The nanorods sensitized the thermolysis of ammonium perchlorate. • Controlled thermal decomposition of nanorods yielded manganese oxide nanoparticles. • MnO nanoparticles formed insitu in the condensed phase enhance the burning rates. - Abstract: Rod-shaped nanostructures of manganese oxalate (MnC{sub 2}O{sub 4}) were synthesized via mild thermal precipitation and aging process. Chemical composition of the MnC{sub 2}O{sub 4} nanorods was confirmed using Fourier transform infra-red (FTIR) spectroscopy and energy dispersive X-ray spectroscopy (EDS). X-ray diffraction (XRD) and selected area electron diffraction (SAED) studies revealed the crystal structure. Field emission scanning electron microscopy (FE-SEM) imaging and high resolution transmission electron microscopy (HR-TEM) were employed to study the structural features of the nanorods. The MnC{sub 2}O{sub 4} nanorods were found to be efficient ballistic modifier for the burning rate enhancement of composite solid propellants (CSPs). Thermal analysis using TGA-DSC showed that MnC{sub 2}O{sub 4} nanorods sensitized the thermal decomposition of ammonium perchlorate (AP) and the CSPs. Controlled thermal decomposition of the MnC{sub 2}O{sub 4} nanorods resulted in the formation of managanese oxide nanoparticles with mesoporosity. A plausible mechanism for the burning rate enhancement using MnC{sub 2}O{sub 4} nanorods was proposed.

  3. Studies on composite solid propellant with tri-modal ammonium perchlorate containing an ultrafine fraction

    Directory of Open Access Journals (Sweden)

    K.V. Suresh Babu

    2017-08-01

    Full Text Available Composite solid propellant is prepared using tri-modal Ammonium perchlorate (AP containing coarse, fine and ultrafine fractions of AP with average particle size (APS 340, 40 and 5 μm respectively, in various compositions and their rheological, mechanical and burn rate characteristics are evaluated. The optimum combination of AP coarse to fine to ultrafine weight fraction was obtained by testing of series of propellant samples by varying the AP fractions at fixed solid loading. The concentration of aluminium was maintained constant throughout the experiments for ballistics requirement. The propellant formulation prepared using AP with coarse to fine to ultrafine ratio of 67:24:9 has lowest viscosity for the propellant paste and highest tensile strength due to dense packing as supported by the literature. A minimum modulus value was also observed at 9 wt. % of ultrafine AP concentration indicates the maximum solids packing density at this ratio of AP fractions. The burn rate is evaluated at different pressures to obtain pressure exponent. Incorporation of ultrafine fraction of AP in propellant increased burn rate without adversely affecting the pressure exponent. Higher solid loading propellants are prepared by increased AP concentration from 67 to 71 wt. % using AP with coarse to fine to ultrafine ratio of 67:24:9. Higher solid content up to 89 wt. % was achieved and hence increased solid motor performance. The unloading viscosity showed a trend with increased AP content and the propellant couldn't able to cast beyond 71 wt. % of AP. Mechanical properties were also studied and from the experiments noticed that % elongation decreased with increased AP content from 67 to 71 wt.%, whereas tensile strength and modulus increased. Burn rate increased with increased AP content and observed that pressure exponent also increased and it is high for the propellant containing with 71 wt.% of AP due to increased oxidiser to fuel ratio. Catalysed

  4. Cu–Co–O nano-catalysts as a burn rate modifier for composite solid propellants

    Directory of Open Access Journals (Sweden)

    D. Chaitanya Kumar Rao

    2016-08-01

    Full Text Available Nano-catalysts containing copper–cobalt oxides (Cu–Co–O have been synthesized by the citric acid (CA complexing method. Copper (II nitrate and Cobalt (II nitrate were employed in different molar ratios as the starting reactants to prepare three types of nano-catalysts. Well crystalline nano-catalysts were produced after a period of 3 hours by the calcination of CA–Cu–Co–O precursors at 550 °C. The phase morphologies and crystal composition of synthesized nano-catalysts were examined using Scanning Electron Microscope (SEM, Energy Dispersive Spectroscopy (EDS and Fourier Transform Infrared Spectroscopy (FTIR methods. The particle size of nano-catalysts was observed in the range of 90 nm–200 nm. The prepared nano-catalysts were used to formulate propellant samples of various compositions which showed high reactivity toward the combustion of HTPB/AP-based composite solid propellants. The catalytic effects on the decomposition of propellant samples were found to be significant at higher temperatures. The combustion characteristics of composite solid propellants were significantly improved by the incorporation of nano-catalysts. Out of the three catalysts studied in the present work, CuCo-I was found to be the better catalyst in regard to thermal decomposition and burning nature of composite solid propellants. The improved performance of composite solid propellant can be attributed to the high crystallinity, low agglomeration and lowering the decomposition temperature of oxidizer by the addition of CuCo-I nano-catalyst.

  5. Experimental study on composite solid propellant material burning rate using algorithm MATLAB

    Directory of Open Access Journals (Sweden)

    Thunaipragasam Selvakumaran

    2016-01-01

    Full Text Available In rocketry application, now-a-days instead of monopropellants slowly composite propellants are introduced. Burning rate of a solid state composite propellant depends on many factors like oxidizer-binder ratio, oxidizer particle size and distribution, particle size and its distribution, pressure, temperature, etc. Several researchers had taken the mass varied composite propellant. In that, the ammonium perchlorate mainly varied from 85 to 90%. This paper deals with the oxidizer rich propellant by allowing small variation of fuel cum binder ranging from 2%, 4%, 6%, and 8% by mass. Since the percent of the binder is very less compared to the oxidizer, the mixture remains in a powder form. The powder samples are used to make a pressed pellet. Experiments were conducted in closed window bomb set-up at pressures of 2, 3.5, and 7 MN/m2. The burning rates are calculated from the combustion photography (images taken by a high-speed camera. These images were processed frame by frame in MATLAB, detecting the edges in the images of the frames. The burning rate is obtained as the slope of the linear fit from MATLAB and observed that the burn rate increases with the mass variation of constituents present in solid state composite propellant. The result indicates a remarkable increase in burn rate of 26.66%, 20%, 16.66%, and 3.33% for Mix 1, 2, 3, 4 compared with Mix 5 at 7 MN/m2. The percentage variations in burn rate between Mix 1 and Mix 5 at 2, 3.5, and 7 MN/m2 are 25.833%, 32.322%, and 26.185%, respectively.

  6. Effective Mechanical Property Estimation of Composite Solid Propellants Based on VCFEM

    Directory of Open Access Journals (Sweden)

    Liu-Lei Shen

    2018-01-01

    Full Text Available A solid rocket motor is one of the critical components of solid missiles, and its life and reliability mostly depend on the mechanical behavior of a composite solid propellant (CSP. Effective mechanical properties are critical material constants to analyze the structural integrity of propellant grain. They are estimated by a numerical method that combines the Voronoi cell finite element method (VCFEM and the homogenization method in the present paper. The correctness of this combined method has been validated by comparing with a standard finite element method and conventional theoretical models. The effective modulus and the effective Poisson’s ratio of a CSP varying with volume fraction and component material properties are estimated. The result indicates that the variations of the volume fraction of inclusions and the properties of the matrix have obvious influences on the effective mechanical properties of a CSP. The microscopic numerical analysis method proposed in this paper can also be used to provide references for the design and the analysis of other large volume fraction composite materials.

  7. Solid propellant impact tests

    International Nuclear Information System (INIS)

    Snow, E.C.

    1976-03-01

    Future space missions, as in the past, call for the continued use of radioisotopes as heat sources for thermoelectric power generators. In an effort to minimize the risk of radioactive contamination of the environment, a complete safety analysis of each such system is necessary. As a part of these analyses, the effects on such a system of a solid propellant fire environment resulting from a catastrophic launch pad abort must be considered. Several impact tests were conducted in which either a simulant MHW-FSA or a steel ball was dropped on the cold, unignited or the hot, burning surface of a block of UTP-3001 solid propellant. The rebound velocities were measured for both surface conditions of the propellant. The resulting coefficient of restitution, determined as the ratio of the components of the impact and rebound velocities perpendicular to the impact surface of the propellant, were not very dependent on whether the surface was cold or hot at the time of impact

  8. Modeling and simulation of the debonding process of composite solid propellants

    Science.gov (United States)

    Feng, Tao; Xu, Jin-sheng; Han, Long; Chen, Xiong

    2017-07-01

    In order to study the damage evolution law of composite solid propellants, the molecular dynamics particle filled algorithm was used to establish the mesoscopic structure model of HTPB(Hydroxyl-terminated polybutadiene) propellants. The cohesive element method was employed for the adhesion interface between AP(Ammonium perchlorate) particle and HTPB matrix and the bilinear cohesive zone model was used to describe the mechanical response of the interface elements. The inversion analysis method based on Hooke-Jeeves optimization algorithm was employed to identify the parameters of cohesive zone model(CZM) of the particle/binder interface. Then, the optimized parameters were applied to the commercial finite element software ABAQUS to simulate the damage evolution process for AP particle and HTPB matrix, including the initiation, development, gathering and macroscopic crack. Finally, the stress-strain simulation curve was compared with the experiment curves. The result shows that the bilinear cohesive zone model can accurately describe the debonding and fracture process between the AP particles and HTPB matrix under the uniaxial tension loading.

  9. The use of image analysis for the study of interfacial bonding in solid composite propellant

    Directory of Open Access Journals (Sweden)

    JASMINA DOSTANIC

    2007-10-01

    Full Text Available In the framework of this research, the program Image Pro Plus was applied for determining the polymer–oxidizer interactions in HTPB-based composite propellants. In order to improve the interactions, different bonding agents were used, and their efficiency was analyzed. The determination of the quantity, area and radius of non-bonded oxidizer crystals is presented. The position of formed cracks in the specimen and their area has a great influence on the mechanical properties of composite propellant. The preparation of the composite propellant in order to enable the photographing of their structure by means of stereoscopic and metallographic microscopes with the digital camera is also described as well.

  10. Development of hydrazinium nitroformate based solid propellants

    NARCIS (Netherlands)

    Schöyer, H.F.R.; Schnorhk, A.J.; Korting, P.A.O.G.; Lit, P.J. van; Mul, J.M.; Gadiot, G.; Meulenbrugge, J.J.

    1995-01-01

    The development of new high-performance propellant combinations requires the establishment of safety and handling characteristics and thermodynamic decomposition and explosive properties. This paper addresses the early development phases of a new composite solid propellant based on HNF as oxidizer

  11. Nonsteady Combustion Mechanisms of Advanced Solid Propellants

    National Research Council Canada - National Science Library

    Branch, Melvyn

    1997-01-01

    .... The individual tasks which we are studying will pursue solid propellant decomposition under unsteady conditions, nonsteady aspects of gas phase flame structure measurements, numerical modeling...

  12. Effects of magnesium-based hydrogen storage materials on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant.

    Science.gov (United States)

    Liu, Leili; Li, Jie; Zhang, Lingyao; Tian, Siyu

    2018-01-15

    MgH 2 , Mg 2 NiH 4 , and Mg 2 CuH 3 were prepared, and their structure and hydrogen storage properties were determined through X-ray photoelectron spectroscopy and thermal analyzer. The effects of MgH 2 , Mg 2 NiH 4 , and Mg 2 CuH 3 on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant were subsequently studied. Results indicated that MgH 2 , Mg 2 NiH 4 , and Mg 2 CuH 3 can decrease the thermal decomposition peak temperature and increase the total released heat of decomposition. These compounds can improve the effect of thermal decomposition of the propellant. The burning rates of the propellant increased using Mg-based hydrogen storage materials as promoter. The burning rates of the propellant also increased using MgH 2 instead of Al in the propellant, but its explosive heat was not enlarged. Nonetheless, the combustion heat of MgH 2 was higher than that of Al. A possible mechanism was thus proposed. Copyright © 2017. Published by Elsevier B.V.

  13. A novel kind of solid rocket propellant

    Energy Technology Data Exchange (ETDEWEB)

    Lo, R.E. [Berlin University of Technology (Germany). Rocket Technology at the Aerospace Institute (ILR)

    1998-09-01

    Cryogenic Solid Propellants (CSPs) combine the simplicity of conventional solid propulsion with the high performance of liquid propulsion. By introducing materials that require cooling for remaining solid, CSPs offer an almost unlimited choice of propellant constituents that mights be selected with respect to specific impulse, density or environmental protection. The prize to be paid for these advantages is the necessity of constant cooling and the requirement of special design features that provide combustion control by moving from deflagration to hybrid like boundary layer combustion. This is achieved by building the solid propellant grains out of macroscopic elements rather than using the quasi homogeneous mixture of conventional composites. The elements may be coated, providing protection and support. Different elements may be designed for individual tasks and serve as modules for ignition, sustained combustion, gas generation, combustion efficiency enhancement, etc. Modular dissected grains offer many new ways of interaction inside the combustion chamber and new degrees of freedom for the designer of such `multiple internal hybrid grains`. At a preliminary level, a study finished in Germany 1997 demonstrated large payload gains when the US space Shuttle and the ARIANE 5 boosters were replaced by CSP-boosters. A very preliminary cost analysis resulted in development costs in the usual magnitude (but not in higher ones). Costs of operation were identified as crucial, but not established. Some experimental work in Germany is scheduled to begin in 1998, almost all details in this article (and many more that were not mentioned - most prominent cost analyses of CSP development and operations) wait for deeper analysis and verification. Actually, a whole new world new of world of chemical propulsion awaits exploration. The topic can be looked up and discussed at the web site of the Advanced Propulsion Workshop of the International Academy of Astronautics. The author

  14. Structure of Partially Premixed Flames and Advanced Solid Propellants

    National Research Council Canada - National Science Library

    Branch, Melvyn

    1998-01-01

    The combustion of solid rocket propellants of advanced energetic materials involves a complex process of decomposition and condensed phase reactions in the solid propellant, gaseous flame reactions...

  15. Propellant selection for ramjets with solid fuel

    Energy Technology Data Exchange (ETDEWEB)

    Schmucker, R H; Lips, H

    1976-03-11

    Ramjet propulsion using solid propellant for post-boost acceleration of missiles exhibits several favorable properties, brought about by heterogeneous combustion. A simplified theory for calculating the performance of possible propellants is presented, and they are classified with respect to maximum fuel-specific impulse. The optimal choice of fuel, from a system standpoint, must consider volume constraints, and defines the requirements for motor geometry.

  16. Developments on HNF based high performance and green solid propellants

    NARCIS (Netherlands)

    Keizers, H.L.J.; Heijden, A.E.D.M. van der; Vliet, L.D. van; Welland-Veltmans, W.H.M.; Ciucci, A.

    2001-01-01

    Worldwide developments are ongoing to develop new and more energetic composite solid propellant formulations for space transportation and military applications. Since the 90's, the use of HNF as a new high performance oxidiser is being reinvestigated. Within European development programmes,

  17. Solid State MEMS Thrusters Using Electrically Controlled Extinguishable Solid Propellant, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ET Materials, LLC developed the first ever electrically controlled extinguishable solid propellant (ECESP). The original propellant developed under Air Force SBIR...

  18. Effect of Propellant Composition to the Temperature Sensitivity of Composite Propellant

    International Nuclear Information System (INIS)

    Aziz, Amir; Mamat, Rizalman; Amin, Makeen; Wan Ali, Wan Khairuddin

    2012-01-01

    The propellant composition is one of several parameter that influencing the temperature sensitivity of composite propellant. In this paper, experimental investigation of temperature sensitivity in burning rate of composite propellant was conducted. Four sets of different propellant compositions had been prepared with the combination of ammonium perchlorate (AP) as an oxidizer, aluminum (Al) as fuel and hydroxy-terminated polybutadiene (HTPB) as fuel and binder. For each mixture, HTPB binder was fixed at 15% and cured with isophorone diisocyanate (IPDI). By varying AP and Al, the effect of oxidizer- fuel mixture ratio (O/F) on the whole propellant can be determined. The propellant strands were manufactured using compression molded method and burnt in a strand burner using wire technique over a range of pressure from 1 atm to 31 atm. The results obtained shows that the temperature sensitivity, a, increases with increasing O/F. Propellant p80 which has O/F ratio of 80/20 gives the highest value of temperature sensitivity which is 1.687. The results shows that the propellant composition has significant effect on the temperature sensitivity of composite propellant

  19. Electric Propellant Solid Rocket Motor Thruster Results Enabling Small Satellites

    OpenAIRE

    Koehler, Frederick; Langhenry, Mark; Summers, Matt; Villarreal, James; Villarreal, Thomas

    2017-01-01

    Raytheon Missile Systems has developed and tested true on/off/restart solid propellant thrusters which are controlled only by electrical current. This new patented class of energetic rocket propellant is safe, controllable and simple. The range of applications for this game changing technology includes attitude control systems and a safe alternative to higher impulse space satellite thrusters. Described herein are descriptions and performance data for several small electric propellant solid r...

  20. Crusader solid propellant best technical approach

    Energy Technology Data Exchange (ETDEWEB)

    Graves, V. [Oak Ridge National Lab., TN (United States); Bader, G. [Fire Support Armament Center, Picatinny Arsenal, NJ (United States); Dolecki, M. [Tank-Automotive Research, Development, and Engineering Center, Picatinny, NJ (United States); Krupski, S. [Benet Weapons Lab., Watervliet Arsenal, NY (United States); Zangrando, R. [Close Combat Armament Center, Picatinny Arsenal, NJ (United States)

    1995-12-01

    The goal of the Solid Propellant Resupply Team is to develop Crusader system concepts capable of automatically handling 155mm projectiles and Modular Artillery Charges (MACs) based on system requirements. The system encompasses all aspects of handling from initial input into a resupply vehicle (RSV) to the final loading into the breech of the self-propelled howitzer (SPH). The team, comprised of persons from military and other government organizations, developed concepts for the overall vehicles as well as their interior handling components. An intermediate review was conducted on those components, and revised concepts were completed in May 1995. A concept evaluation was conducted on the finalized concepts, from both a systems level and a component level. The team`s Best Technical Approach (BTA) concept was selected from that evaluation. Both vehicles in the BTA have a front-engine configuration with the crew situated behind the engine-low in the vehicles. The SPH concept utilizes an automated reload port at the rear of the vehicle, centered high. The RSV transfer boom will dock with this port to allow automated ammunition transfer. The SPH rearm system utilizes fully redundant dual loaders. Active magazines are used for both projectiles and MACs. The SPH also uses a nonconventional tilted ring turret configuration to maximize the available interior volume in the vehicle. This configuration can be rearmed at any elevation angle but only at 0{degree} azimuth. The RSV configuration is similar to that of the SPH. The RSV utilizes passive storage racks with a pick-and-place manipulator for handling the projectiles and active magazines for the MACs. A telescoping transfer boom extends out the front of the vehicle over the crew and engine.

  1. Design and simulation on the morphing composite propeller (Conference Presentation)

    Science.gov (United States)

    Chen, Fanlong; Li, Qinyu; Liu, Liwu; Lan, Xin; Liu, Yanju; Leng, Jinsong

    2017-04-01

    As one of the most crucial part of the unmanned underwater vehicle (UUV), the composite propeller plays an important role on the UUV's performance. As the composite propeller behaves excellent properties in hydroelastic facet and acoustic suppression, it attracts increasing attentions all over the globe. This paper goes a step further based on this idea, and comes up with a novel concept of "morphing composite propeller" (MCP) to improve the performance of the conventional composite propeller (CCP) to anticipate the improved propeller can perform better to propel the UUV. Based on the new concept, a novel MCP is designed. Each blade of the propeller is assembled with an active rotatable flap (ARF) to change the blade's local camber with flap rotation. Then the transmission mechanism (TM) has been designed and housed in the propeller blade to push the ARF. With the ARF rotating, the UUV can be propelled by different thrusts under certain rotation velocities of the propeller. Based on the design, the Fluent is exploited to analyze the fluid dynamics around the propeller. Finally, based on the design and hydrodynamic analysis, the structural response for the novel morphing composite propeller is calculated. The propeller blade is simplified and layered with composite materials. And the structure response of an MCP is obtained with various rotation angle under the hydrodynamic pressure. This simulation can instruct the design and fabrication techniques of the MCP.

  2. Integral performance optimum design for multistage solid propellant rocket motors

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongtao (Shaanxi Power Machinery Institute (China))

    1989-04-01

    A mathematical model for integral performance optimization of multistage solid propellant rocket motors is presented. A calculation on a three-stage, volume-fixed, solid propellant rocket motor is used as an example. It is shown that the velocity at burnout of intermediate-range or long-range ballistic missile calculated using this model is four percent greater than that using the usual empirical method.

  3. Development of strand burner for solid propellant burning rate studies

    International Nuclear Information System (INIS)

    Aziz, A; Mamat, R; Ali, W K Wan

    2013-01-01

    It is well-known that a strand burner is an apparatus that provides burning rate measurements of a solid propellant at an elevated pressure in order to obtain the burning characteristics of a propellant. This paper describes the facilities developed by author that was used in his studies. The burning rate characteristics of solid propellant have be evaluated over five different chamber pressures ranging from 1 atm to 31 atm using a strand burner. The strand burner has a mounting stand that allows the propellant strand to be mounted vertically. The strand was ignited electrically using hot wire, and the burning time was recorded by electronic timer. Wire technique was used to measure the burning rate. Preliminary results from these techniques are presented. This study shows that the strand burner can be used on propellant strands to obtain accurate low pressure burning rate data

  4. Advanced technologies available for future solid propellant grains

    Energy Technology Data Exchange (ETDEWEB)

    Thepenier, J. [SNPE Propulsion, St Medard en Jalles (France); Fonblanc, G. [SNPE Propulsion, Vert le Petit (France). Centre de Recherche de Bouchet

    2001-06-01

    Significant advances have been made during the last decade in several fields of solid propulsion: the advances have enabled new savings in the motor development phase and in recurring costs, because they help limit the number of prototypes and tests. The purpose of the paper is to describe the improvements achieved by SNPE in solid grain technologies, making these technologies available for new developments in more efficient and reliable future SRMs: new energetic molecules, new solid propellants, new processes for grain manufacturing, quick response grain design tools associated with advanced models for grain performance predictions. Using its expertise in chemical synthesis, SNPE develops new molecules to fit new energetic material requirements. Tests based on new propellant formulations have produced good results in the propellant performance/safety behavior ratio. New processes have been developed simultaneously to reduce the manufacturing costs of the new propellants. In addition, the grain design has been optimized by using the latest generation of predictive theoretical tools supported by a large data bank of experimental parameters resulting from over 30 years' experience in solid propulsion: computer-aided method for the preliminary grain design; advanced models for SRM operating and performance predictions. All these technologies are available for industrial applications in future developments of solid propellant grains. (author)

  5. Rocket Solid Propellant Alternative Based on Ammonium Dinitramide

    Directory of Open Access Journals (Sweden)

    Grigore CICAN

    2017-03-01

    Full Text Available Due to the continuous run for a green environment the current article proposes a new type of solid propellant based on the fairly new synthesized oxidizer, ammonium dinitramide (ADN. Apart of having a higher specific impulse than the worldwide renowned oxidizer, ammonium perchlorate, ADN has the advantage, of leaving behind only nitrogen, oxygen and water after decomposing at high temperatures and therefore totally avoiding the formation of hydrogen chloride fumes. Based on the oxidizer to fuel ratios of the current formulations of the major rocket solid booster (e.g. Space Shuttle’s SRB, Ariane 5’s SRB which comprises mass variations of ammonium perchlorate oxidizer (70-75%, atomized aluminum powder (10-18% and polybutadiene binder (12-20% a new solid propellant was formulated. As previously stated, the new propellant formula and its variations use ADN as oxidizer and erythritol tetranitrate as fuel, keeping the same polybutadiene as binder.

  6. Concept and performance study of turbocharged solid propellant ramjet

    Science.gov (United States)

    Li, Jiang; Liu, Kai; Liu, Yang; Liu, Shichang

    2018-06-01

    This study proposes a turbocharged solid propellant ramjet (TSPR) propulsion system that integrates a turbocharged system consisting of a solid propellant (SP) air turbo rocket (ATR) and the fuel-rich gas generator of a solid propellant ramjet (SPR). First, a suitable propellant scheme was determined for the TSPR. A solid hydrocarbon propellant is used to generate gas for driving the turbine, and a boron-based fuel-rich propellant is used to provide fuel-rich gas to the afterburner. An appropriate TSPR structure was also determined. The TSPR's thermodynamic cycle was analysed to prove its theoretical feasibility. The results showed that the TSPR's specific cycle power was larger than those of SP-ATR and SPR and thermal efficiency was slightly less than that of SP-ATR. Overall, TSPR showed optimal performance in a wide flight envelope. The specific impulses and specific thrusts of TSPR, SP-ATR, and SPR in the flight envelope were calculated and compared. TSPR's flight envelope roughly overlapped that of SP-ATR, its specific impulse was larger than that of SP-ATR, and its specific thrust was larger than those of SP-ATR and SPR. Attempts to improve the TSPR off-design performance prompted our proposal of a control plan for off-design codes in which both the turbocharger corrected speed and combustor excess gas coefficient are kept constant. An off-design performance model was established by analysing the TSPR working process. We concluded that TSPR with a constant corrected speed had wider flight envelope, higher thrust, and higher specific impulse than TSPR with a constant physical speed determined by calculating the performance of off-design TSPR codes under different control plans. The results of this study can provide a reference for further studies on TSPRs.

  7. Linear stability analysis in a solid-propellant rocket motor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.M.; Kang, K.T.; Yoon, J.K. [Agency for Defense Development, Taejon (Korea, Republic of)

    1995-10-01

    Combustion instability in solid-propellant rocket motors depends on the balance between acoustic energy gains and losses of the system. The objective of this paper is to demonstrate the capability of the program which predicts the standard longitudinal stability using acoustic modes based on linear stability analysis and T-burner test results of propellants. Commercial ANSYS 5.0A program can be used to calculate the acoustic characteristic of a rocket motor. The linear stability prediction was compared with the static firing test results of rocket motors. (author). 11 refs., 17 figs.

  8. Burning Characteristics of Ammonium-Nitrate-Based Composite Propellants with a Hydroxyl-Terminated Polybutadiene/Polytetrahydrofuran Blend Binder

    Directory of Open Access Journals (Sweden)

    Makoto Kohga

    2012-01-01

    Full Text Available Ammonium-nitrate-(AN- based composite propellants prepared with a hydroxyl-terminated polybutadiene (HTPB/polytetrahydrofuran (PTHF blend binder have unique thermal decomposition characteristics. In this study, the burning characteristics of AN/HTPB/PTHF propellants are investigated. The specific impulse and adiabatic flame temperature of an AN-based propellant theoretically increases with an increase in the proportion of PTHF in the HTPB/PTHF blend. With an AN/HTPB propellant, a solid residue is left on the burning surface of the propellant, and the shape of this residue is similar to that of the propellant. On the other hand, an AN/HTPB/PTHF propellant does not leave a solid residue. The burning rates of the AN/HTPB/PTHF propellant are not markedly different from those of the AN/HTPB propellant because some of the liquefied HTPB/PTHF binder cover the burning surface and impede decomposition and combustion. The burning rates of an AN/HTPB/PTHF propellant with a burning catalyst are higher than those of an AN/HTPB propellant supplemented with a catalyst. The beneficial effect of the blend binder on the burning characteristics is clarified upon the addition of a catalyst. The catalyst suppresses the negative influence of the liquefied binder that covers the burning surface. Thus, HTPB/PTHF blend binders are useful in improving the performance of AN-based propellants.

  9. Rheokinetic Analysis of Hydroxy Terminated Polybutadiene Based Solid Propellant Slurry

    Directory of Open Access Journals (Sweden)

    Abhay K Mahanta

    2010-01-01

    Full Text Available The cure kinetics of propellant slurry based on hydroxy-terminated polybutadiene (HTPB and toluene diisocyanate (TDI polyurethane reaction has been studied by viscosity build up method. The viscosity (ɳ–time (t plots conform to the exponential function ɳ = aebt, where a & b are empirical constants. The rate constants (k for viscosity build up at various shear rate (rpm, evaluated from the slope of dɳ/dt versus ɳ plots at different temperatures, were found to vary from 0.0032 to 0.0052 min-1. It was observed that the increasing shear rate did not have significant effect on the reaction rate constants for viscosity build up of the propellant slurry. The activation energy (Eɳ, calculated from the Arrhenius plots, was found to be 13.17±1.78 kJ mole-1, whereas the activation enthalpy (∆Hɳ* and entropy (∆Sɳ* of the propellant slurry, calculated from Eyring relationship, were found to be 10.48±1.78 kJ mole-1 and –258.51± 5.38 J mole-1K-1, respectively. The reaction quenching temperature of the propellant slurry was found to be -9 ° C, based upon the experimental data. This opens up an avenue for a “freeze-and-store”, then “warm-up and cast”, mode of manufacturing of very large solid rocket propellant grains.

  10. MEMS-Based Solid Propellant Rocket Array Thruster

    Science.gov (United States)

    Tanaka, Shuji; Hosokawa, Ryuichiro; Tokudome, Shin-Ichiro; Hori, Keiichi; Saito, Hirobumi; Watanabe, Masashi; Esashi, Masayoshi

    The prototype of a solid propellant rocket array thruster for simple attitude control of a 10 kg class micro-spacecraft was completed and tested. The prototype has 10×10 φ0.8 mm solid propellant micro-rockets arrayed at a pitch of 1.2 mm on a 20×22 mm substrate. To realize such a dense array of micro-rockets, each ignition heater is powered from the backside of the thruster through an electrical feedthrough which passes along a propellant cylinder wall. Boron/potassium nitrate propellant (NAB) is used with/without lead rhodanide/potassium chlorate/nitrocellulose ignition aid (RK). Impulse thrust was measured by a pendulum method in air. Ignition required electric power of at least 3 4 W with RK and 4 6 W without RK. Measured impulse thrusts were from 2×10-5 Ns to 3×10-4 Ns after the calculation of compensation for air dumping.

  11. Specific Impulses Losses in Solid Propellant Rockets

    Science.gov (United States)

    1974-12-17

    the solid we go back to the wall flux. Platinum film thermometric probes [77, 78], developed for somewhat similar problems, were used without succ...AS: E Paper 63-41A 207, 1964. [83) A.D. KIDEIR .A XU - J.A. CAHILL - The density of liquid aluminium oxide. J. Inovg. luc.. Chem. vol.14, no 3-4, p...IELLOR - I. GLL.ASIJ - Augo.nted ignition effi ciency for aluminium . Combustion Science rand Tcchnology, vol. I, p. 437, 1970. [90s EIJ. IJJ tBAU

  12. Longitudinal acoustic instabilities in slender solid propellant rockets : linear analysis

    OpenAIRE

    García Schafer, Juan Esteban; Liñán Martínez, Amable

    2001-01-01

    To describe the acoustic instabilities in the combustion chambers of laterally burning solid propellant rockets the interaction of the mean flow with the acoustic waves is analysed, using multiple scale techniques, for realistic cases in which the combustion chamber is slender and the nozzle area is small compared with the cross-sectional area of the chamber. Associated with the longitudinal acoustic oscillations we find vorticity and entropy waves, with a wavelength typically small compared ...

  13. High-Fidelity Microstructural Characterization and Performance Modeling of Aluminized Composite Propellant

    International Nuclear Information System (INIS)

    Kosiba, Graham D.; Wixom, Ryan R.; Oehlschlaeger, Matthew A.

    2017-01-01

    Image processing and stereological techniques were used to characterize the heterogeneity of composite propellant and inform a predictive burn rate model. Composite propellant samples made up of ammonium perchlorate (AP), hydroxyl-terminated polybutadiene (HTPB), and aluminum (Al) were faced with an ion mill and imaged with a scanning electron microscope (SEM) and x-ray tomography (micro-CT). Properties of both the bulk and individual components of the composite propellant were determined from a variety of image processing tools. An algebraic model, based on the improved Beckstead-Derr-Price model developed by Cohen and Strand, was used to predict the steady-state burning of the aluminized composite propellant. In the presented model the presence of aluminum particles within the propellant was introduced. The thermal effects of aluminum particles are accounted for at the solid-gas propellant surface interface and aluminum combustion is considered in the gas phase using a single global reaction. In conclusion, properties derived from image processing were used directly as model inputs, leading to a sample-specific predictive combustion model.

  14. Working-cycle processes in solid-propellant rocket engines (Handbook). Rabochie protsessy v raketnykh dvigateliakh tverdogo topliva /Spravochnik/

    Energy Technology Data Exchange (ETDEWEB)

    Shishkov, A.A.; Panin, S.D.; Rumiantsev, B.V.

    1989-01-01

    Physical and mathematical models of processes taking place in solid-propellant rocket engines and gas generators are presented in a systematic manner. The discussion covers the main types of solid propellants, the general design and principal components of solid-propellant rocket engines, the combustion of a solid-propellant charge, thermodynamic calculation of combustion and outflow processes, and analysis of gasdynamic processes in solid-propellant rocket engines. 40 refs.

  15. High-Pressure Burning Rate Studies of Solid Rocket Propellants

    Science.gov (United States)

    2013-01-01

    monopropellant burning rate. The self-de§agration rates of neat AP are plotted in Fig. 2 for both pressed pellets and single crystals. There is agreement...rate data from various investigators: 1 ¡ [2]; pressed pellets : 2 ¡ [3], 3 ¡ [4], and 4 ¡ [2]; and single crystals: 5 ¡ [5], and 6 ¡ [6]. Line ¡ AP...7]. Strand or window burners have had more use in the solid propellant community. There are numerous types and styles of combustion vessels, but they

  16. A Study of Flame Physics and Solid Propellant Rocket Physics

    National Research Council Canada - National Science Library

    Buckmaster, John

    2007-01-01

    ..., the combustion of heterogeneous propellants containing aluminum, the use of a genetic algorithm to optimally define false-kinetics parameters in propellant combustion modeling, the calculation of fluctuations...

  17. OPTIMIZATION OF POTASSIUM NITRATE BASED SOLID PROPELLANT GRAINS FORMULATION USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Oladipupo Olaosebikan Ogunleye

    2015-08-01

    Full Text Available This study was designed to evaluate the effect of propellant formulation and geometry on the solid propellant grains internal ballistic performance using core, bates, rod and tubular and end-burn geometries. Response Surface Methodology (RSM was used to analyze and optimize the effect of sucrose, potassium nitrate and carbon on the chamber pressure, temperature, thrust and specific impulse of the solid propellant grains through Central Composite Design (CCD of the experiment. An increase in potassium nitrate increased the specific impulse while an increase in sucrose and carbon decreased specific impulse. The coefficient of determination (R2 for models of chamber pressure, temperature, thrust and specific impulse in terms of composition and geometry were 0.9737, 0.9984, 0.9745 and 0.9589, respectively. The optimum specific impulse of 127.89 s, pressure (462201 Pa, temperature (1618.3 K and thrust (834.83 N were obtained using 0.584 kg of sucrose, 1.364 kg of potassium nitrate and 0.052 kg of carbon as well as bate geometry. There was no significant difference between the calculated and experimented ballistic properties at p < 0.05. The bate grain geometry is more efficient for minimizing the oscillatory pressure in the combustion chamber.

  18. Mixing and combustion enhancement of Turbocharged Solid Propellant Ramjet

    Science.gov (United States)

    Liu, Shichang; Li, Jiang; Zhu, Gen; Wang, Wei; Liu, Yang

    2018-02-01

    Turbocharged Solid Propellant Ramjet is a new concept engine that combines the advantages of both solid rocket ramjet and Air Turbo Rocket, with a wide operation envelope and high performance. There are three streams of the air, turbine-driving gas and augment gas to mix and combust in the afterburner, and the coaxial intake mode of the afterburner is disadvantageous to the mixing and combustion. Therefore, it is necessary to carry out mixing and combustion enhancement research. In this study, the numerical model of Turbocharged Solid Propellant Ramjet three-dimensional combustion flow field is established, and the numerical simulation of the mixing and combustion enhancement scheme is conducted from the aspects of head region intake mode to injection method in afterburner. The results show that by driving the compressed air to deflect inward and the turbine-driving gas to maintain strong rotation, radial and tangential momentum exchange of the two streams can be enhanced, thereby improving the efficiency of mixing and combustion in the afterburner. The method of injecting augment gas in the transverse direction and making sure the injection location is as close as possible to the head region is beneficial to improve the combustion efficiency. The outer combustion flow field of the afterburner is an oxidizer-rich environment, while the inner is a fuel-rich environment. To improve the efficiency of mixing and combustion, it is necessary to control the injection velocity of the augment gas to keep it in the oxygen-rich zone of the outer region. The numerical simulation for different flight conditions shows that the optimal mixing and combustion enhancement scheme can obtain high combustion efficiency and have excellent applicability in a wide working range.

  19. Combustion of Solid Propellants (La Combustion des Propergols Solides)

    Science.gov (United States)

    1991-07-01

    the of ether and ethyl alcohol and removing objective of these lectures to give a this solvent. Instead of having a fibrous comprehensive understanding...do cetto esrne do Les propergols composites, A matrice confifrences une description tout A fait A polymarique charg~o pst, un oxydant at un jour des...rusa., De nouveaux souvant suppos6 qua la vitesa des gaz de oxydes de for ultrafirts mont aujourd’hui combustion est n~gligeable at qua d~velopps pour

  20. Solid Propellant Microthruster Design, Fabrication, and Testing for Nanosatellites

    Science.gov (United States)

    Sathiyanathan, Kartheephan

    This thesis describes the design, fabrication, and testing of a solid propellant microthruster (SPM), which is a two-dimensional matrix of millimeter-sized rockets each capable of delivering millinewtons of thrust and millinewton-seconds of impulse to perform fine orbit and attitude corrections. The SPM is a potential payload for nanosatellites to increase spacecraft maneuverability and is constrained by strict mass, volume, and power requirements. The dimensions of the SPM in the millimeter-scale result in a number of scaling issues that need consideration such as a low Reynolds number, high heat loss, thermal and radical quenching, and incomplete combustion. The design of the SPM, engineered to address these issues, is outlined. The SPM fabrication using low-cost commercial off-the-shelf materials and standard micromachining is presented. The selection of a suitable propellant and its customization are described. Experimental results of SPM firing to demonstrate successful ignition and sustained combustion are presented for three configurations: nozzleless, sonic nozzle, and supersonic nozzle. The SPM is tested using a ballistic pendulum thrust stand. Impulse and thrust values are calculated and presented. The performance values of the SPM are found to be consistent with existing designs.

  1. The thermal decomposition behavior of ammonium perchlorate and of an ammonium-perchlorate-based composite propellant

    Energy Technology Data Exchange (ETDEWEB)

    Behrens, R.; Minier, L.

    1998-03-24

    The thermal decomposition of ammonium perchlorate (AP) and ammonium-perchlorate-based composite propellants is studied using the simultaneous thermogravimetric modulated beam mass spectrometry (STMBMS) technique. The main objective of the present work is to evaluate whether the STMBMS can provide new data on these materials that will have sufficient detail on the reaction mechanisms and associated reaction kinetics to permit creation of a detailed model of the thermal decomposition process. Such a model is a necessary ingredient to engineering models of ignition and slow-cookoff for these AP-based composite propellants. Results show that the decomposition of pure AP is controlled by two processes. One occurs at lower temperatures (240 to 270 C), produces mainly H{sub 2}O, O{sub 2}, Cl{sub 2}, N{sub 2}O and HCl, and is shown to occur in the solid phase within the AP particles. 200{micro} diameter AP particles undergo 25% decomposition in the solid phase, whereas 20{micro} diameter AP particles undergo only 13% decomposition. The second process is dissociative sublimation of AP to NH{sub 3} + HClO{sub 4} followed by the decomposition of, and reaction between, these two products in the gas phase. The dissociative sublimation process occurs over the entire temperature range of AP decomposition, but only becomes dominant at temperatures above those for the solid-phase decomposition. AP-based composite propellants are used extensively in both small tactical rocket motors and large strategic rocket systems.

  2. Solid propellant processing factor in rocket motor design

    Science.gov (United States)

    1971-01-01

    The ways are described by which propellant processing is affected by choices made in designing rocket engines. Tradeoff studies, design proof or scaleup studies, and special design features are presented that are required to obtain high product quality, and optimum processing costs. Processing is considered to include the operational steps involved with the lining and preparation of the motor case for the grain; the procurement of propellant raw materials; and propellant mixing, casting or extrusion, curing, machining, and finishing. The design criteria, recommended practices, and propellant formulations are included.

  3. Non-linear analysis of solid propellant burning rate behavior

    Energy Technology Data Exchange (ETDEWEB)

    Junye Wang [Zhejiang Univ. of Technology, College of Mechanical and Electrical Engineering, Hanzhou (China)

    2000-07-01

    The parametric analysis of the thermal wave model of the non-steady combustion of solid propellants is carried out under a sudden compression. First, to observe non-linear effects, solutions are obtained using a computer under prescribed pressure variations. Then, the effects of rearranging the spatial mesh, additional points, and the time step on numerical solutions are evaluated. Finally, the behaviour of the thermal wave combustion model is examined under large heat releases (H) and a dynamic factor ({beta}). The numerical predictions show that (1) the effect of a dynamic factor ({beta}), related to the magnitude of dp/dt, on the peak burning rate increases as the value of beta increases. However, unsteady burning rate 'runaway' does not appear and will return asymptotically to ap{sup n}, when {beta}{>=}10.0. The burning rate 'runaway' is a numerical difficulty, not a solution to the models. (2) At constant beta and m, the amplitude of the burning rate increases with increasing H. However, the increase in the burning rate amplitude is stepwise, and there is no apparent intrinsic instability limit. A damped oscillation of burning rate occurs when the value of H is less. However, when H>1.0, the state of an intrinsically unstable model is composed of repeated, amplitude spikes, i.e. an undamped oscillation occurs. (3) The effect of the time step on the peak burning rate increases as H increases. (Author)

  4. Characterization of a Green Solid Electric Propellant Microthruster for Small Spacecraft

    Data.gov (United States)

    National Aeronautics and Space Administration — The development of Solid Electric Propellants is an emerging topic of research with major implications in the field of space propulsion from the micro to macro...

  5. Construction and design of solid-propellant rocket engines. Konstruktsiia i proektirovanie raketnykh dvigatelei tverdogo topliva

    Energy Technology Data Exchange (ETDEWEB)

    Fakhrutdinov, I.K.; Kotel' nikov, A.V.

    1987-01-01

    Methods for assessing the durability of different components of solid-propellant rocket engines are presented. The following aspects of engine development are discussed: task formulation, parameter calculation, construction scheme selection, materials, and durability assessment. 45 references.

  6. Combustion diagnosis for analysis of solid propellant rocket abort hazards: Role of spectroscopy

    Science.gov (United States)

    Gill, W.; Cruz-Cabrera, A. A.; Donaldson, A. B.; Lim, J.; Sivathanu, Y.; Bystrom, E.; Haug, A.; Sharp, L.; Surmick, D. M.

    2014-11-01

    Solid rocket propellant plume temperatures have been measured using spectroscopic methods as part of an ongoing effort to specify the thermal-chemical-physical environment in and around a burning fragment of an exploded solid rocket at atmospheric pressures. Such specification is needed for launch safety studies where hazardous payloads become involved with large fragments of burning propellant. The propellant burns in an off-design condition producing a hot gas flame loaded with burning metal droplets. Each component of the flame (soot, droplets and gas) has a characteristic temperature, and it is only through the use of spectroscopy that their temperature can be independently identified.

  7. Combustion diagnosis for analysis of solid propellant rocket abort hazards: Role of spectroscopy

    International Nuclear Information System (INIS)

    Gill, W; Cruz-Cabrera, A A; Bystrom, E; Donaldson, A B; Haug, A; Sharp, L; Lim, J; Sivathanu, Y; Surmick, D M

    2014-01-01

    Solid rocket propellant plume temperatures have been measured using spectroscopic methods as part of an ongoing effort to specify the thermal-chemical-physical environment in and around a burning fragment of an exploded solid rocket at atmospheric pressures. Such specification is needed for launch safety studies where hazardous payloads become involved with large fragments of burning propellant. The propellant burns in an off-design condition producing a hot gas flame loaded with burning metal droplets. Each component of the flame (soot, droplets and gas) has a characteristic temperature, and it is only through the use of spectroscopy that their temperature can be independently identified

  8. Effect of gamma radiation on properties of a composite rocket propellant

    International Nuclear Information System (INIS)

    Dedgaonkar, V.G.; Pol, V.G.; Navle, P.B.; Ghorpade, V.G.; Wani, V.S.

    2000-01-01

    Gamma radiation was employed for modifying the properties of a composite rocket propellant prepared in a standard way. It was observed that when the same gamma dose was imparted to hydroxy terminated polybutadiene (HTPB) then converted into propellant, the enhancement in the properties was much larger than the irradiated propellant samples. (author)

  9. A stochastic pocket model for aluminum agglomeration in solid propellants

    Energy Technology Data Exchange (ETDEWEB)

    Gallier, Stany [SNPE Materiaux Energetiques, Vert le Petit (France)

    2009-04-15

    A new model is derived to estimate the size and fraction of aluminum agglomerates at the surface of a burning propellant. The basic idea relies on well-known pocket models in which aluminum is supposed to aggregate and melt within pocket volumes imposed by largest oxidizer particles. The proposed model essentially relaxes simple assumptions of previous pocket models on propellant structure by accounting for an actual microstructure obtained by packing. The use of statistical tools from stochastic geometry enables to determine a statistical pocket size volume and hence agglomerate diameter and agglomeration fraction. Application to several AP/Al propellants gives encouraging results that are shown to be superior to former pocket models. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  10. Simulation technique on combustion of solid propellant; Kotai suishin`yaku nensho no simyureshon gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Iida, Akihide.; Bazaki, Hakobu.; Douke, Kiyotaka. [Asahi Chemical Industry Corp., Tokyo (Japan). Oita Plant

    1999-04-30

    The burning area of propellant grain is one of the most important parameter in conducting of design on solid rocket performance. However, it has been difficult to calculate the burning area of propellant grain with precise and speed by geometrical way since most of propellant configuration have been adopted as complicated. In the present study, the simulation system was developed and produced, which was adapted `particle chasing method` to and made ot compute the burning area transition. Moreover, the reliability on computation by the system was check up on. It was found that the discrepancy of calculation between by the geometrical way and by the system was less than 1%. (author)

  11. Studies on Flame Spread with Sudden Expansions of Ports of Solid Propellant Rockets under Elevated Pressure.

    OpenAIRE

    B.N. Raghunandan; N.S. Madhavan; C. Sanjeev; V.R.S. Kumar

    1996-01-01

    A detailed experimental study on flame spread over non-uniform ports of solid propellant rockets has been carried out. An idealised. 2-dimensional laboratory motor was used for the experimental study with the aid of cinephotography. Freshly prepared rectangular HTPB propellant with backward facing step was used as the specimenfor this study. It has been shown conclusively that under certain conditions of step location. step height and port height which govern the velocity of gases at the step...

  12. Effect of Chamber Pressurization Rate on Combustion and Propagation of Solid Propellant Cracks

    Science.gov (United States)

    Yuan, Wei-Lan; Wei, Shen; Yuan, Shu-Shen

    2002-01-01

    area of the propellant grain satisfies the designed value. But cracks in propellant grain can be generated during manufacture, storage, handing and so on. The cracks can provide additional surface area for combustion. The additional combustion may significantly deviate the performance of the rocket motor from the designed conditions, even lead to explosive catastrophe. Therefore a thorough study on the combustion, propagation and fracture of solid propellant cracks must be conducted. This paper takes an isolated propellant crack as the object and studies the effect of chamber pressurization rate on the combustion, propagation and fracture of the crack by experiment and theoretical calculation. deformable, the burning inside a solid propellant crack is a coupling of solid mechanics and combustion dynamics. In this paper, a theoretical model describing the combustion, propagation and fracture of the crack was formulated and solved numerically. The interaction of structural deformation and combustion process was included in the theoretical model. The conservation equations for compressible fluid flow, the equation of state for perfect gas, the heat conducting equation for the solid-phase, constitutive equation for propellant, J-integral fracture criterion and so on are used in the model. The convective burning inside the crack and the propagation and fracture of the crack were numerically studied by solving the set of nonlinear, inhomogeneous gas-phase governing equations and solid-phase equations. On the other hand, the combustion experiments for propellant specimens with a precut crack were conducted by RTR system. Predicted results are in good agreement with experimental data, which validates the reasonableness of the theoretical model. Both theoretical and experimental results indicate that the chamber pressurization rate has strong effects on the convective burning in the crack, crack fracture initiation and fracture pattern.

  13. Homogenization Issues in the Combustion of Heterogeneous Solid Propellants

    Science.gov (United States)

    Chen, M.; Buckmaster, J.; Jackson, T. L.; Massa, L.

    2002-01-01

    We examine random packs of discs or spheres, models for ammonium-perchlorate-in-binder propellants, and discuss their average properties. An analytical strategy is described for calculating the mean or effective heat conduction coefficient in terms of the heat conduction coefficients of the individual components, and the results are verified by comparison with those of direct numerical simulations (dns) for both 2-D (disc) and 3-D (sphere) packs across which a temperature difference is applied. Similarly, when the surface regression speed of each component is related to the surface temperature via a simple Arrhenius law, an analytical strategy is developed for calculating an effective Arrhenius law for the combination, and these results are verified using dns in which a uniform heat flux is applied to the pack surface, causing it to regress. These results are needed for homogenization strategies necessary for fully integrated 2-D or 3-D simulations of heterogeneous propellant combustion.

  14. A Study of Flame Physics and Solid Propellant Rocket Physics

    Science.gov (United States)

    2007-10-01

    and ellipsoids, and the packing of pellets relevant to igniter modeling. Other topics are the instabilities of smolder waves, premixed flame...instabilities in narrow tubes, and flames supported by a spinning porous plug burner . Much of this work has been reported in the high-quality archival...perchlorate in fuel binder, the combustion of model propellant packs of ellipses and ellipsoids, and the packing of pellets relevant to igniter modeling

  15. Design and Fabrication of a 200N Thrust Rocket Motor Based on NH4ClO4+Al+HTPB as Solid Propellant

    Science.gov (United States)

    Wahid, Mastura Ab; Ali, Wan Khairuddin Wan

    2010-06-01

    The development of rocket motor using potassium nitrate, carbon and sulphur mixture has successfully been developed by researchers and students from UTM and recently a new combination for solid propellant is being created. The new solid propellant will combine a composition of Ammonium perchlorate, NH4ClO4 with aluminium, Al and Hydroxyl Terminated Polybutadiene, HTPB as the binder. It is the aim of this research to design and fabricate a new rocket motor that will produce a thrust of 200N by using this new solid propellant. A static test is done to obtain the thrust produced by the rocket motor and analyses by observation and also calculation will be done. The experiment for the rocket motor is successful but the thrust did not achieve its required thrust.

  16. Feasibility Study and Demonstration of an Aluminum and Ice Solid Propellant

    Directory of Open Access Journals (Sweden)

    Timothee L. Pourpoint

    2012-01-01

    Full Text Available Aluminum-water reactions have been proposed and studied for several decades for underwater propulsion systems and applications requiring hydrogen generation. Aluminum and water have also been proposed as a frozen propellant, and there have been proposals for other refrigerated propellants that could be mixed, frozen in situ, and used as solid propellants. However, little work has been done to determine the feasibility of these concepts. With the recent availability of nanoscale aluminum, a simple binary formulation with water is now feasible. Nanosized aluminum has a lower ignition temperature than micron-sized aluminum particles, partly due to its high surface area, and burning times are much faster than micron aluminum. Frozen nanoscale aluminum and water mixtures are stable, as well as insensitive to electrostatic discharge, impact, and shock. Here we report a study of the feasibility of an nAl-ice propellant in small-scale rocket experiments. The focus here is not to develop an optimized propellant; however improved formulations are possible. Several static motor experiments have been conducted, including using a flight-weight casing. The flight weight casing was used in the first sounding rocket test of an aluminum-ice propellant, establishing a proof of concept for simple propellant mixtures making use of nanoscale particles.

  17. Application of transient burning rate model of solid propellant in electrothermal-chemical launch simulation

    Directory of Open Access Journals (Sweden)

    Yan-jie Ni

    2016-04-01

    Full Text Available A 30 mm electrothermal-chemical (ETC gun experimental system is employed to research the burning rate characteristics of 4/7 high-nitrogen solid propellant. Enhanced gas generation rates (EGGR of propellants during and after electrical discharges are verified in the experiments. A modified 0D internal ballistic model is established to simulate the ETC launch. According to the measured pressure and electrical parameters, a transient burning rate law including the influence of EGGR coefficient by electric power and pressure gradient (dp/dt is added into the model. The EGGR coefficient of 4/7 high-nitrogen solid propellant is equal to 0.005 MW−1. Both simulated breech pressure and projectile muzzle velocity accord with the experimental results well. Compared with Woodley's modified burning rate law, the breech pressure curves acquired by the transient burning rate law are more consistent with test results. Based on the parameters calculated in the model, the relationship among propellant burning rate, pressure gradient (dp/dt and electric power is analyzed. Depending on the transient burning rate law and experimental data, the burning of solid propellant under the condition of plasma is described more accurately.

  18. Development of efficient finite elements for structural integrity analysis of solid rocket motor propellant grains

    International Nuclear Information System (INIS)

    Marimuthu, R.; Nageswara Rao, B.

    2013-01-01

    Solid propellant rocket motors (SRM) are regularly used in the satellite launch vehicles which consist of mainly three different structural materials viz., solid propellant, liner, and casing materials. It is essential to assess the structural integrity of solid propellant grains under the specified gravity, thermal and pressure loading conditions. For this purpose finite elements developed following the Herrmann formulation are: twenty node brick element (BH20), eight node quadrilateral plane strain element (PH8) and, eight node axi-symmetric solid of revolution element (AH8). The time-dependent nature of the solid propellant grains is taken into account utilizing the direct inverse method of Schepary to specify the effective Young's modulus and Poisson's ratio. The developed elements are tested considering various problems prior to implementation in the in-house software package (viz., Finite Element Analysis of STructures, FEAST). Several SRM configurations are analyzed to assess the structural integrity under different loading conditions. Finite element analysis results are found to be in good agreement with those obtained earlier from MARC software. -- Highlights: • Developed efficient Herrmann elements. • Accuracy of finite elements demonstrated solving several known solution problems. • Time dependent structural response obtained using the direct inverse method of Schepary. • Performed structural analysis of grains under gravity, thermal and pressure loads

  19. Development and Characterization of Fast Burning Solid Fuels/Propellants for Hybrid Rocket Motors with High Volumetric Efficiency

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposed work is to develop several fast burning solid fuels/fuel-rich solid propellants for hybrid rocket motor applications. In the...

  20. Solid propellant ignition motors for LH_2/LOX rocket engine system

    OpenAIRE

    ARAKI, Tetsuo; AKIBA, Ryojiro; HASHIMOTO, Yasunari; AIHARA, Kenji; TOMITA, Etsu; YASUDA, Seiichi; 荒木, 哲夫; 秋葉, 鐐二郎; 橋本, 保成; 相原, 賢二; 富田, 悦; 安田, 誠一

    1983-01-01

    Solid propellant ignition motors are used in the series of experiments of the 10 ton LH_2/LOX engine featured by the channel wall thrust chamber, This paper presents design specification, experiments and results obtained by actual applications of those ignition motors.

  1. Radiative Ignition of fine-ammonium perchlorate composite propellants

    Energy Technology Data Exchange (ETDEWEB)

    Cain, Jeremy; Brewster, M. Quinn [Department of Mechanical Science and Industrial Engineering, University of Illinois, Urbana, IL 61801 (United States)

    2006-08-15

    Radiative ignition of quasi-homogeneous mixtures of ammonium perchlorate (AP) and hydroxyterminated polybutadiene (HTPB) binder has been investigated experimentally. Solid propellants consisting of fine AP (2 {mu}m) and HTPB binder ({proportional_to}76/24% by mass) were ignited by CO{sub 2} laser radiation. The lower boundary of a go/no-go ignition map (minimum ignition time vs. heat flux) was obtained. Opacity was varied by adding carbon black up to 1% by mass. Ignition times ranged from 0.78 s to 0.076 s for incident fluxes ranging from 60 W/cm{sup 2} to 400 W/cm{sup 2}. It was found that AP and HTPB are sufficiently strongly absorbing of 10.6 {mu}m CO{sub 2} laser radiation (absorption coefficient {approx}250 cm{sup -1}) so that the addition of carbon black in amounts typical of catalysts or opacitymodifying agents (up to 1%) would have only a small influence on radiative ignition times at 10.6 {mu}m. A simple theoretical analysis indicated that the ignition time-flux data are consistent with in-depth absorption effects. Furthermore, this analysis showed that the assumption of surface absorption is not appropriate, even for this relatively opaque system. For broadband visible/near-infrared radiation, such as from burning metal/oxide particle systems, the effects of in-depth absorption would probably be even stronger. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  2. Hydro-Elastic Tailoring and Optimization of a Composite Marine Propeller

    DEFF Research Database (Denmark)

    Blasques, José Pedro Albergaria Amaral; Berggreen, Christian; Andersen, Poul

    2008-01-01

    The following paper deals with the design and optimization of a flexible composite marine propeller. The blade shape is obtained from an existing high skew metal propeller. The aim is to tailor the laminate to control the elastic couplings and therefore the deformed shape of the blade. The develo...

  3. Thermal Decomposition Behaviors and Burning Characteristics of AN/Nitramine-Based Composite Propellant

    Science.gov (United States)

    Naya, Tomoki; Kohga, Makoto

    2015-04-01

    Ammonium nitrate (AN) has attracted much attention due to its clean burning nature as an oxidizer. However, an AN-based composite propellant has the disadvantages of low burning rate and poor ignitability. In this study, we added nitramine of cyclotrimethylene trinitramine (RDX) or cyclotetramethylene tetranitramine (HMX) as a high-energy material to AN propellants to overcome these disadvantages. The thermal decomposition and burning rate characteristics of the prepared propellants were examined as the ratio of AN and nitramine was varied. In the thermal decomposition process, AN/RDX propellants showed unique mass loss peaks in the lower temperature range that were not observed for AN or RDX propellants alone. AN and RDX decomposed continuously as an almost single oxidizer in the AN/RDX propellant. In contrast, AN/HMX propellants exhibited thermal decomposition characteristics similar to those of AN and HMX, which decomposed almost separately in the thermal decomposition of the AN/HMX propellant. The ignitability was improved and the burning rate increased by the addition of nitramine for both AN/RDX and AN/HMX propellants. The increased burning rates of AN/RDX propellants were greater than those of AN/HMX. The difference in the thermal decomposition and burning characteristics was caused by the interaction between AN and RDX.

  4. Current state of the art of HNF based composite propellants

    NARCIS (Netherlands)

    Ciucci, A.; Frota, O.; Welland, W.H.M.; Heijden, A.E.D.M. van der; Leeming, B.; Bellerby, J.M.; Brotzu, A.

    2004-01-01

    The main activities currently performed for the development of HNF-based propellants are presented. The objectives and approach adopted are described. The results obtained on the HNF decomposition mechanism and on the re- and co-crystallisation of HNF with potential propellant ingredients are

  5. Extension of a simplified computer program for analysis of solid-propellant rocket motors

    Science.gov (United States)

    Sforzini, R. H.

    1973-01-01

    A research project to develop a computer program for the preliminary design and performance analysis of solid propellant rocket engines is discussed. The following capabilities are included as computer program options: (1) treatment of wagon wheel cross sectional propellant configurations alone or in combination with circular perforated grains, (2) calculation of ignition transients with the igniter treated as a small rocket engine, (3) representation of spherical circular perforated grain ends as an alternative to the conical end surface approximation used in the original program, and (4) graphical presentation of program results using a digital plotter.

  6. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Terry, Brandon C., E-mail: terry13@purdue.edu [School of Aeronautics and Astronautics, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States); Sippel, Travis R. [Department of Mechanical Engineering, Iowa State University, 2025 Black Engineering, Ames, IA 50011 (United States); Pfeil, Mark A. [School of Aeronautics and Astronautics, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States); Gunduz, I.Emre; Son, Steven F. [School of Mechanical Engineering, Purdue University, Zucrow Laboratories, 500 Allison Rd, West Lafayette, IN 47907 (United States)

    2016-11-05

    Highlights: • Al-Li alloy propellant has increased ideal specific impulse over neat aluminum. • Al-Li alloy propellant has a near complete reduction in HCl acid formation. • Reduction in HCl was verified with wet bomb experiments and DSC/TGA-MS/FTIR. - Abstract: Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (I{sub SP}). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal I{sub SP} by ∼7 s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5 ± 4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption.

  7. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy

    International Nuclear Information System (INIS)

    Terry, Brandon C.; Sippel, Travis R.; Pfeil, Mark A.; Gunduz, I.Emre; Son, Steven F.

    2016-01-01

    Highlights: • Al-Li alloy propellant has increased ideal specific impulse over neat aluminum. • Al-Li alloy propellant has a near complete reduction in HCl acid formation. • Reduction in HCl was verified with wet bomb experiments and DSC/TGA-MS/FTIR. - Abstract: Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (I_S_P). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal I_S_P by ∼7 s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5 ± 4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption.

  8. Workshop Report: Fundamental Reactions in Solid Propellant Combustion

    Science.gov (United States)

    1979-05-01

    combustion conditions. 6. What effect might a pressure-induced phase transition to a polymorph other than 6- HMX have on the pressure slope break during...pure HMX as well. Nevertheless, it is recommended that the high pressure polymorphs of HMX and RDX be determined. It was also felt that there...plateau burning phenomena E. Solid phase, surface, gas phase reactions F. Phase transitions : melting, vaporization, polymorphs G. Flame

  9. Removing hydrochloric acid exhaust products from high performance solid rocket propellant using aluminum-lithium alloy.

    Science.gov (United States)

    Terry, Brandon C; Sippel, Travis R; Pfeil, Mark A; Gunduz, I Emre; Son, Steven F

    2016-11-05

    Hydrochloric acid (HCl) pollution from perchlorate based propellants is well known for both launch site contamination, as well as the possible ozone layer depletion effects. Past efforts in developing environmentally cleaner solid propellants by scavenging the chlorine ion have focused on replacing a portion of the chorine-containing oxidant (i.e., ammonium perchlorate) with an alkali metal nitrate. The alkali metal (e.g., Li or Na) in the nitrate reacts with the chlorine ion to form an alkali metal chloride (i.e., a salt instead of HCl). While this technique can potentially reduce HCl formation, it also results in reduced ideal specific impulse (ISP). Here, we show using thermochemical calculations that using aluminum-lithium (Al-Li) alloy can reduce HCl formation by more than 95% (with lithium contents ≥15 mass%) and increase the ideal ISP by ∼7s compared to neat aluminum (using 80/20 mass% Al-Li alloy). Two solid propellants were formulated using 80/20 Al-Li alloy or neat aluminum as fuel additives. The halide scavenging effect of Al-Li propellants was verified using wet bomb combustion experiments (75.5±4.8% reduction in pH, ∝ [HCl], when compared to neat aluminum). Additionally, no measurable HCl evolution was detected using differential scanning calorimetry coupled with thermogravimetric analysis, mass spectrometry, and Fourier transform infrared absorption. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Safety test No. S-6, launch pad abort sequential test Phase II: solid propellant fire

    International Nuclear Information System (INIS)

    Snow, E.C.

    1975-08-01

    In preparation for the Lincoln Laboratory's LES 8/9 space mission, a series of tests was performed to evaluate the nuclear safety capability of the Multi-Hundred Watt (MHW) Radioisotope Thermoelectric Generator (RTG) to be used to supply power for the satellite. One such safety test is Test No. S-6, Launch Pad Abort Sequential Test. The objective of this test was to subject the RTG and its components to the sequential environments characteristic of a catastrophic launch pad accident to evaluate their capability to contain the 238 PuO 2 fuel. This sequence of environments was to have consisted of the blast overpressure and fragments, followed by the fireball, low velocity impact on the launch pad, and solid propellant fire. The blast overpressure and fragments were subsequently eliminated from this sequence. The procedures and results of Phase II of Test S-6, Solid Propellant Fire are presented. In this phase of the test, a simulant Fuel Sphere Assembly (FSA) and a mockup of a damaged Heat Source Assembly (HSA) were subjected to single proximity solid propellant fires of approximately 10-min duration. Steel was introduced into both tests to simulate the effects of launch pad debris and the solid rocket motor (SRM) casing that might be present in the fire zone. (TFD)

  11. Safety test of an improved multihundred watt FSA: launch abort, solid propellant fire

    International Nuclear Information System (INIS)

    Seabourn, C.M.

    1978-07-01

    This safety test consisted of exposing a simulant-fueled Improved Multihundred Watt Fuel Sphere Assembly, containing a Pt-3008 sphere holding the fuel simulant, to a single proximity fire of UTP-3001 solid rocket propellant for 10.5 min. The graphite outside shell sustained only minor abrasion damage. It was covered on one side with a heavy deposit of alumina from the fire mixed with silica from the test bed. The Pt-3008 shell had small amounts of carbon, alumina, and silica deposited on its surface but sustained no other damage. The PT-3008 sphere was not breached, and therefore the fuel sphere assembly would not release fuel in a solid-propellant fire of a launch abort. 12 figures

  12. Particle size determination in small solid propellant rocket motors using the diffractively scattered light method.

    OpenAIRE

    Cramer, Robert Grewelle.

    1982-01-01

    Approved for public release; distribution unlimited A dual beam apparatus was developed which simultaneously measured particle size (D32) at the entrance and exit of an exhaust nozzle of a small solid propellant rocket motor. The diameters were determined using measurements of dif fractiveiy scattered laser power spectra. The apparatus was calibrated by using spherical glass beads and aluminum oxide powder. Measurements were successfully made at both locations. Because of...

  13. The development of the micro-solid propellant thruster array with improved repeatability

    International Nuclear Information System (INIS)

    Seo, Daeban; Kwon, Sejin; Lee, Jongkwang

    2012-01-01

    This paper presents the development of a micro-solid propellant thruster array with improved repeatability. The repeatability and low performance variation of each thruster unit with a high ignition success rate is essential in micro-solid propellant thruster array. To date, the study on the improvement of the repeatability has not yet been reported. As the first step for this study, we propose a new type of micro igniter, using a glass wafer called the heater-contact micro igniter. This igniter is also designed to improve the ignition characteristics of a glass-based micro igniter. The prototype of the igniter array is designed and fabricated to establish its fabrication process and to conduct its performance evaluation. Through the firing test, the performance of the heater-contact micro igniter is verified. The 5 × 5 sized micro-solid propellant thruster array is designed and fabricated applying the developed heater-contact igniter. The measured average thrust of each thruster unit is 2.542 N, and calculated standard deviation is 0.369 N. The calculated average total impulse and its standard deviation are 0.182 and 0.04 mNs, respectively. Based on these results, the improvement of repeatability is verified. Finally, the ignition control system of the micro-thruster array is developed. (paper)

  14. Study of combustion properties of a solid propellant by highly time-resolved passive FTIR

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Liming; Zhang, Lin; Li, Yan; Liu, Bingping; Wang, Junde [Laboratory of Advanced Spectroscopy, Nanjing University of Science and Technology, Nanjing 210014 (China)

    2006-10-15

    With a time resolution of 0.125 s and a spectral resolution of 4 cm{sup -1}, emission spectra of the combustion process of a solid propellant were recorded by highly time-resolved passive FTIR. Some gaseous combustion products, such as H{sub 2}O, CO, CO{sub 2}, NO and HCl, were distinguished by the characteristic emission band of each molecule. The equation for flame temperature calculation based on the diatomic molecule emission fine structure theory was improved through judicious utilization of the spectral running number 'm' which makes the temperature measurement simpler and faster. Some combustion information of the solid propellant had been given including the characteristic spectral profile, the distribution of the absolute spectral energy, the distribution of the combustion flame temperature, and the concentration distributions of HCl and NO versus burning time. The results will provide theoretical and experimental bases for improving the formula and raising combustion efficiency of solid propellant, and developing the design of rocket motor, infrared guidance and antiguidance systems. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  15. MIGRATION OF A MOONLET IN A RING OF SOLID PARTICLES: THEORY AND APPLICATION TO SATURN'S PROPELLERS

    International Nuclear Information System (INIS)

    Crida, Aurelien; Papaloizou, John C. B.; Rein, Hanno; Charnoz, Sebastien; Salmon, Julien

    2010-01-01

    Hundred-meter-sized objects have been identified by the Cassini spacecraft in Saturn's A ring through the so-called propeller features they create in the ring. These moonlets should migrate due to their gravitational interaction with the ring; in fact, some orbital variations have been detected. The standard theory of type I migration of planets in protoplanetary disks cannot be applied to the ring system as it is pressureless. Thus, we compute the differential torque felt by a moonlet embedded in a two-dimensional disk of solid particles, with a flat surface density profile, both analytically and numerically. We find that the corresponding migration rate is too small to explain the observed variations of the propeller's orbit in Saturn's A ring. However, local density fluctuations (due to gravity wakes in the marginally gravitationally stable A ring) may exert a stochastic torque on a moonlet. Our simulations show that this torque can be large enough to account for the observations depending on the parameters of the rings. We find that on timescales of several years the migration of propellers is likely to be dominated by stochastic effects (while the former, non-stochastic migration dominates after ∼10 4 -10 5 years). In that case, the migration rates provided by observations so far suggest that the surface density of the A ring should be on the order of 700 kg m -2 . The age of the propellers should not exceed 1-100 million years depending on the dominant migration regime.

  16. Effect of ammonium perchlorate grain sizes on the combustion of solid rocket propellant

    Energy Technology Data Exchange (ETDEWEB)

    Hegab, A.; Balabel, A. [Menoufia Univ., Menoufia (Egypt). Faculty of Engineering

    2007-07-01

    The combustion of heterogeneous solid rocket propellant consisting of ammonium perchlorate (AP) particles was discussed with reference to the chemical and physical complexity of the propellant and the microscopic scale of the combustion zone. This study considered the primary flame between the decomposition products of the binder and the AP oxidizer; the primary diffusion flame from the oxidizer; density and conductivity of the AP and binder; temperature-dependent gas-phase transport properties; and, an unsteady non-planer regression surface. Three different random packing disc models for the AP particles imbedded in a matrix of a hydroxyl terminated polybutadience (HTPB) fuel-binder were used as a base of the combustion code. The models have different AP grain sizes and distribution with the fuel binder. A 2D calculation was developed for the combustion of heterogeneous solid propellant, accounting for the gas phase physics, the solid phase physics and an unsteady non-planar description of the regressing propellant surface. The mathematical model described the unsteady burning of a heterogeneous propellant by simultaneously solving the combustion fields in the gas phase and the thermal field in the solid phase with appropriate jump condition across the gas/solid interface. The gas-phase kinetics was represented by a two-step reaction mechanism for the primary premixed flame and the primary diffusion flame between the decomposition products of the HTPB and the oxidizer. The essentially-non-oscillatory (ENO) scheme was used to describe the propagation of the unsteady non-planer regression surface. The results showed that AP particle size has a significant effect on the combustion surface deformation as well as on the burning rate. This study also determined the effect of various parameters on the surface propagation speed, flame structure, and the burning surface geometry. The speed by which the combustion surface recedes was found to depend on the exposed pressure

  17. Test data from small solid propellant rocket motor plume measurements (FA-21)

    Science.gov (United States)

    Hair, L. M.; Somers, R. E.

    1976-01-01

    A program is described for obtaining a reliable, parametric set of measurements in the exhaust plumes of solid propellant rocket motors. Plume measurements included pressures, temperatures, forces, heat transfer rates, particle sampling, and high-speed movies. Approximately 210,000 digital data points and 15,000 movie frames were acquired. Measurements were made at points in the plumes via rake-mounted probes, and on the surface of a large plate impinged by the exhaust plume. Parametric variations were made in pressure altitude, propellant aluminum loading, impinged plate incidence angle and distance from nozzle exit to plate or rake. Reliability was incorporated by continual use of repeat runs. The test setup of the various hardware items is described along with an account of test procedures. Test results and data accuracy are discussed. Format of the data presentation is detailed. Complete data are included in the appendix.

  18. Dynamic analysis of solid propellant grains subjected to ignition pressurization loading

    Science.gov (United States)

    Chyuan, Shiang-Woei

    2003-11-01

    Traditionally, the transient analysis of solid propellant grains subjected to ignition pressurization loading was not considered, and quasi-elastic-static analysis was widely adopted for structural integrity because the analytical task gets simplified. But it does not mean that the dynamic effect is not useful and could be neglected arbitrarily, and this effect usually plays a very important role for some critical design. In order to simulate the dynamic response for solid rocket motor, a transient finite element model, accompanied by concepts of time-temperature shift principle, reduced integration and thermorheologically simple material assumption, was used. For studying the dynamic response, diverse ignition pressurization loading cases were used and investigated in the present paper. Results show that the dynamic effect is important for structural integrity of solid propellant grains under ignition pressurization loading. Comparing the effective stress of transient analysis and of quasi-elastic-static analysis, one can see that there is an obvious difference between them because of the dynamic effect. From the work of quasi-elastic-static and transient analyses, the dynamic analysis highlighted several areas of interest and a more accurate and reasonable result could be obtained for the engineer.

  19. Finite element analysis of propellant of solid rocket motor during ship motion

    Directory of Open Access Journals (Sweden)

    Kai Qu

    2013-03-01

    Full Text Available In order to simulate the stress and strain of solid rocket motors (SRMs, a finite element analysis model was established. The stress spectra of the SRM elements with respect to time in the case that the vessel cruises under a certain shipping condition were obtained by simulation. According to the analysis of the simulation results, a critical zone was confirmed, and the Mises stress amplitudes of the different critical zones were acquired. The results show that the maximum stress and strain of SRM are less than the maximum tensile strength and elongation, respectively, of the propellant. The cumulative damage of the motor must also be evaluated by random fatigue loading.

  20. Research on combustion instability and application to solid propellant rocket motors. II.

    Science.gov (United States)

    Culick, F. E. C.

    1972-01-01

    Review of the current state of analyses of combustion instability in solid-propellant rocket motors, citing appropriate measurements and observations. The work discussed has become increasingly important, both for the interpretation of laboratory data and for predicting the transient behavior of disturbances in full-scale motors. Two central questions are considered - namely, linear stability and nonlinear behavior. Several classes of problems are discussed as special cases of a general approach to the analysis of combustion instability. Application to motors, and particularly the limitations presently understood, are stressed.

  1. Hydro-elastic analysis and optimization of a composite marine propeller

    DEFF Research Database (Denmark)

    Blasques, José Pedro Albergaria Amaral; Berggreen, Christian; Andersen, Poul

    2010-01-01

    The present paper addresses the design and optimization of a flexible composite marine propeller. The aim is to tailor the laminate to control the deformed shape of the blade and consequently the developed thrust. The development of a hydro-elastic model is presented, and the laminate lay-up which...

  2. Propelling Ariane. The Vulcain engines and the solid propellant engines; Propulser Ariane. Les moteurs Vulcain et les moteurs a propergol solide

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1997-12-31

    The development of the Vulcain program was ensured thanks to a European cooperation with an ESA (European Space Agency) financing. The CNES (European Centre for Space Studies) has ensured the technical and financial direction of the program and gave the control of the development to the SEP. The manufacturing of the Vulcain engine is managed under the Arianespace contract, in charge of the marketing of the Ariane 5 launcher. The overall engineering of the engine and its tests were carried out by the SEP in Vernon (France) and Lampoldshausen (Germany) test facilities. SEP has also developed and built the hydrogen turbo-pump, the gas generator and its feeding valves. Several companies are involved in the development of this engine: DASA for the combustion chamber, Fiat Avio for the oxygen turbo-pump, Volvo Aero Corp. for the divergent and the hydrogen and oxygen turbines, Techspace Aero for the chamber injection valves and the drain and hot gases valves, Microtechnica for the electro-valves and check valves, SPE for the firing and start-up equipments, Avica for the feeding lines, Devtec for the supports, and MAN for the cardan and the thermal protection. This paper describes the functioning principle of the Vulcain engine, and of the two solid propellant fuel acceleration stages of the Ariane 5 launcher. Some future projects of the SEP are also described: the dual liquid-fuels engine and the plasma engine. (J.S.)

  3. Burning characteristics of ammonium nitrate-based composite propellants supplemented with ammonium dichromate

    Energy Technology Data Exchange (ETDEWEB)

    Kohga, Makoto; Nishino, Saeko [Department of Applied Chemistry, National Defense Academy, Yokosuka, Kanagawa 239-8686 (Japan)

    2009-08-15

    Ammonium nitrate (AN)-based composite propellants have attracted much attention, primarily because of the clean burning nature of AN as an oxidizer. However, such propellants have some disadvantages such as poor ignition and low burning rate. Ammonium dichromate (ADC) is used as a burning catalyst for AN-based propellants; however, the effect of ADC on the burning characteristics has yet to be sufficiently delineated. The burning characteristics of AN/ADC propellants prepared with various contents of AN and ADC have been investigated in this study. The theoretical performance of an AN-based propellant is improved by the addition of ADC. The increase in the burning rate is enhanced and the pressure deflagration limit (PDL) becomes lower with increasing amount of ADC added. The increasing ratio of the burning rate with respect to the amount of ADC is independent of the AN content and the combustion pressure. The optimal amount of ADC for improving the burning characteristics has been determined. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  4. Seismic tests at the HDR facility using explosives and solid propellant rockets

    International Nuclear Information System (INIS)

    Corvin, P.; Steinhilber, H.

    1981-01-01

    In blast tests the HDR reactor building and its mechanical equipment were subjected to earthquake-type excitations through the soil and the foundation. A series of six tests was carried out, two tests being made with HDR facility under operating conditions (BWR conditions, 285 0 C, 70 bar). The charges were placed in boreholes at a depth of 4 to 10 m and a distance of 16 to 25 m from the reactor building. The tests with solid propellant rockets were made in order to try a new excitation technique. The rockets used in these tests were of compact design and had a short combustion period (500 ms) at high constant thrust (100 kN per combustion chamber). These rockets were fixed to the concrete dome of the building in such a way that the thrust generated during the combustion of the propellant resulted in an impulsive load acting on the building. This type of excitation was selected with a view to investigating the global effects of the load case 'aircraft impact' on the building and the mechanical equipment. In the four tests made so far, up to four rockets were ignited simultaneously, so that the maximum impulse was 2 x 10 5 Ns. The excitation level can be markedly increased by adding further rockets. This excitation technique was characterised by excellent reproducibility of the load parameters. (orig./HP)

  5. Development of a computerized analysis for solid propellant combustion instability with turbulence

    Science.gov (United States)

    Chung, T. J.; Park, O. Y.

    1988-01-01

    A multi-dimensional numerical model has been developed for the unsteady state oscillatory combustion of solid propellants subject to acoustic pressure disturbances. Including the gas phase unsteady effects, the assumption of uniform pressure across the flame zone, which has been conventionally used, is relaxed so that a higher frequency response in the long flame of a double-base propellant can be calculated. The formulation is based on a premixed, laminar flame with a one-step overall chemical reaction and the Arrhenius law of decomposition with no condensed phase reaction. In a given geometry, the Galerkin finite element solution shows the strong resonance and damping effect at the lower frequencies, similar to the result of Denison and Baum. Extended studies deal with the higher frequency region where the pressure varies in the flame thickness. The nonlinear system behavior is investigated by carrying out the second order expansion in wave amplitude when the acoustic pressure oscillations are finite in amplitude. Offset in the burning rate shows a negative sign in the whole frequency region considered, and it verifies the experimental results of Price. Finally, the velocity coupling in the two-dimensional model is discussed.

  6. Computation of turbulent reacting flow in a solid-propellant ducted rocket

    Science.gov (United States)

    Chao, Yei-Chin; Chou, Wen-Fuh; Liu, Sheng-Shyang

    1995-05-01

    A mathematical model for computation of turbulent reacting flows is developed under general curvilinear coordinate systems. An adaptive, streamline grid system is generated to deal with the complex flow structures in a multiple-inlet solid-propellant ducted rocket (SDR) combustor. General tensor representations of the k-epsilon and algebraic stress (ASM) turbulence models are derived in terms of contravariant velocity components, and modification caused by the effects of compressible turbulence is also included in the modeling. The clipped Gaussian probability density function is incorporated in the combustion model to account for fluctuations of properties. Validation of the above modeling is first examined by studying mixing and reacting characteristics in a confined coaxial-jet problem. This is followed by study of nonreacting and reacting SDR combustor flows. The results show that Gibson and Launder's ASM incorporated with Sarkar's modification for compressible turbulence effects based on the general curvilinear coordinate systems yields the most satisfactory prediction for this complicated SDR flowfield.

  7. MIR/NIR/FIR characterization of poly-ammo and poly-bamo and their precursors as energetic binders to Be used in solid propellants

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Jose Irineu S. de; Diniz, Milton F.; Kawamoto, Aparecida M.; Dutra, Rita C.L. [Divisao de Quimica (AQI) Instituto de Aeronautica e Espaco (IAE) do Comando-Geral de Tecnologia Aeroespacial (CTA), Praca Marechal Eduardo Gomes, 50 Campus do CTA - Vila das Acacias, 12228-904 Sao Jose dos Campos - SP (Brazil); Keicher, Thomas [Fraunhofer Institut Chemische Technologie (ICT), Joseph-von-Fraunhofer-Str. 7, 76327 Pfinztal (Germany)

    2006-10-15

    To establish the relation between structure and properties of composite solid propellants it is important to know the structure of the elastomeric binder that has been used in the system. Therefore this study is focused on the characterization of polymers containing energetic groups that has been synthesized at ICT. The characterization uses the wide spectral band of infrared, NIR/MIR/FIR. This gives an identification of the analytical bands and allows quantitative and kinetic studies of these compounds. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  8. Solid composite electrolytes for lithium batteries

    Science.gov (United States)

    Kumar, Binod; Scanlon, Jr., Lawrence G.

    2000-01-01

    Solid composite electrolytes are provided for use in lithium batteries which exhibit moderate to high ionic conductivity at ambient temperatures and low activation energies. In one embodiment, a ceramic-ceramic composite electrolyte is provided containing lithium nitride and lithium phosphate. The ceramic-ceramic composite is also preferably annealed and exhibits an activation energy of about 0.1 eV.

  9. Composite Solid Fuel: Research of Formation Parameters

    Directory of Open Access Journals (Sweden)

    Tabakaev Roman

    2016-01-01

    Full Text Available Involving of local low-grade fuels resources in fuel and energy balance is actual question of research in the present. In this paper the possibility of processing low-grade fuel in the solid fuel composite was considered. The aim of the work is to define the optimal parameters for formation of the solid composite fuel. A result of researches determined that dextrin content in the binder allows to obtain solid composite fuel having the highest strength. The drying temperature for the various fuels was determined: for pellets production was 20-80 °C, for briquettes – 20-40 °C.

  10. A multilayered thick cylindrical shell under internal pressure and thermal loads applicable to solid propellant rocket motors

    Energy Technology Data Exchange (ETDEWEB)

    Renganathan, K.; Nageswara Rao, B.; Jana, M.K. [Vikram Sarabhai Space Centre, Trivandrum (India). Structural Engineering Group

    2000-09-01

    A solid propellant rocket motor can be considered to be made of various circumferential layers of different properties. A simple procedure is described here to obtain an analytical solution for the general case of multilayered thick cyclindrical shell for internal pressure and thermal loads. This analytical procedure is useful in the preliminary design analysis of solid propellant rocket motors. Since solid propellant material is of viscoelastic behaviour an approximate viscoelastic solution methodology for the multilayered shell is described for estimation of time dependent solutions of propellant grain in a rocket motor. The analytical solution for a two layer reinforced thick cylindrical shell available in the literature is shown to be a special case of the present analytical solution. The results from the present analytical solution for multilayers is found to be in good agreement with FEA results. (orig.) [German] Der grundlegende Aufbau von Feststoffraketenmotoren kann auf einen Zylinder aus mehreren Schichten mit unterschiedlichen Eigenschaften zurueckgefuehrt werden. Eine einfache Berechnungsprozedur fuer die analytische Loesung des allgemeinen Falles eines mehrschichtigen Zylinders unter innerem Druck und thermischer Belastung wird hier vorgestellt. Diese analytische Methodik ist fuer den Auslegungsprozess von Feststoffraketenmotoren von grundlegender Bedeutung. Das viskoelastische Fliessverhalten des festen Brennstoffes, das den zeitlichen Ablauf des Verbrennungsprozesses wesentlich bestimmt, wird durch ein Naeherungsverfahren gut erfasst. Ein in der Literatur enthaltenes spezielles Ergebnis fuer einen zweischaligen verstaerkten Zylinder ergibt sich als Sonderfall der hier vorgestellten Methodik. Die analytisch erhaltenen Loesungen fuer mehrschichtige Aufbauten sind in guter Uebereinstimmung mit mittels der FEM ermittelten Ergebnisse. (orig.)

  11. Evaluation of Flygt Propeller Xixers for Double Shell Tank (DST) High Level Waste Auxiliary Solids Mobilization

    Energy Technology Data Exchange (ETDEWEB)

    PACQUET, E.A.

    2000-07-20

    The River Protection Project (RPP) is planning to retrieve radioactive waste from the single-shell tanks (SST) and double-shell tanks (DST) underground at the Hanford Site. This waste will then be transferred to a waste treatment plant to be immobilized (vitrified) in a stable glass form. Over the years, the waste solids in many of the tanks have settled to form a layer of sludge at the bottom. The thickness of the sludge layer varies from tank to tank, from no sludge or a few inches of sludge to about 15 ft of sludge. The purpose of this technology and engineering case study is to evaluate the Flygt{trademark} submersible propeller mixer as a potential technology for auxiliary mobilization of DST HLW solids. Considering the usage and development to date by other sites in the development of this technology, this study also has the objective of expanding the knowledge base of the Flygt{trademark} mixer concept with the broader perspective of Hanford Site tank waste retrieval. More specifically, the objectives of this study delineated from the work plan are described.

  12. Quantity Distance for the Kennedy Space Center Vehicle Assembly Building for Solid Propellant Fueled Launchers

    Science.gov (United States)

    Stover, Steven; Diebler, Corey; Frazier, Wayne

    2006-01-01

    The NASA KSC VAB was built to process Apollo launchers in the 1960's, and later adapted to process Space Shuttles. The VAB has served as a place to assemble solid rocket motors (5RM) and mate them to the vehicle's external fuel tank and Orbiter before rollout to the launch pad. As Space Shuttle is phased out, and new launchers are developed, the VAB may again be adapted to process these new launchers. Current launch vehicle designs call for continued and perhaps increased use of SRM segments; hence, the safe separation distances are in the process of being re-calculated. Cognizant NASA personnel and the solid rocket contractor have revisited the above VAB QD considerations and suggest that it may be revised to allow a greater number of motor segments within the VAB. This revision assumes that an inadvertent ignition of one SRM stack in its High Bay need not cause immediate and complete involvement of boosters that are part of a vehicle in adjacent High Bay. To support this assumption, NASA and contractor personnel proposed a strawman test approach for obtaining subscale data that may be used to develop phenomenological insight and to develop confidence in an analysis model for later use on full-scale situations. A team of subject matter experts in safety and siting of propellants and explosives were assembled to review the subscale test approach and provide options to NASA. Upon deliberations regarding the various options, the team arrived at some preliminary recommendations for NASA.

  13. Differential scanning calorimetric study of HTPB based composite propellants in presence of nano ferric oxide

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Prajakta R.; Krishnamurthy, V.N.; Joshi, Satyawati S. [Department of Chemistry, University of Pune, Pune 411007 (India)

    2006-12-15

    A comparative study of the thermal decomposition of ammonium perchlorate (AP)/hydroxy terminated polybutadiene (HTPB) based composite propellants has been carried out in presence and absence of nano iron oxide at different heating rates in a dynamic nitrogen atmosphere using differential scanning calorimetry. The pronounced effect was a lowering of the high temperature decomposition by 49 C. A higher heat release up to 40% was observed in presence of nano ferric oxide (3.5 nm). The kinetic parameters were evaluated using the Kissinger method. The increase of the rate constant in the catalyzed propellant confirmed the enhancement of the catalytic activity of ammonium perchlorate. The scanning electron micrographs of nano Fe{sub 2}O{sub 3} incorporated in HTPB revealed a well-separated characteristic necklace-like structure of {alpha}-Fe{sub 2}O{sub 3} particles at high magnification. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  14. The Effect of Propellant Optical Properties on Composite Solid Propellant Combustion

    Science.gov (United States)

    1991-01-01

    10.0 [cal/gJ CpAP . = 1.3 [J/(g K)1 LhrMp =433. [cal/g] CpfTBp = 1.3 [J/(g K)] Using the experimental burning rates, the surface temperatures of the AP...Photo- Flash Lamps." Journatl of the Optical Society of North America, Vol. 37, No. 8. pp. 652-659, 1947. 17. Parry, D.L.. Ph.D. Thesis, The University of...the light emitters in photoflash lamps. In 1947, Brockman 4 made spectroscopic measurements of the light emitted by flash lamps filled with aluminum

  15. Aluminum agglomeration involving the second mergence of agglomerates on the solid propellants burning surface: Experiments and modeling

    Science.gov (United States)

    Ao, Wen; Liu, Xin; Rezaiguia, Hichem; Liu, Huan; Wang, Zhixin; Liu, Peijin

    2017-07-01

    The agglomeration of aluminum particles usually occurs on the burning surface of aluminized composite propellants. It leads to low propellant combustion efficiency and high two-phase flow losses. To reach a thorough understanding of aluminum agglomeration behaviors, agglomeration processes, and particles size distribution of Al/AP/RDX/GAP propellants were studied by using a cinephotomicrography experimental technique, under 5 MPa. Accumulation, aggregation, and agglomeration phenomena of aluminum particles have been inspected, as well as the flame asymmetry of burning agglomerates. Results reveals that the dependency of the mean and the maximum agglomeration diameter to the burning rate and the virgin aluminum size have the same trend. A second-time mergence of multiple agglomerates on the burning surface is unveiled. Two typical modes of second mergence are concluded, based upon vertical and level movement of agglomerates, respectively. The latter mode is found to be dominant and sometimes a combination of the two modes may occur. A new model of aluminum agglomeration on the burning surface of composite propellants is derived to predict the particulates size distribution with a low computational amount. The basic idea is inspired from the well-known pocket models. The pocket size of the region formed by adjacent AP particles is obtained through scanning electron microscopy of the propellant cross-section coupled to an image processing method. The second mergence mechanism, as well as the effect of the burning rate on the agglomeration processes, are included in the present model. The mergence of two agglomerates is prescribed to occur only if their separation distance is less than a critical value. The agglomerates size distribution resulting from this original model match reasonably with the experimental data. Moreover, the present model gives superior results for mean agglomeration diameter compared to common empirical and pocket models. The average prediction

  16. Simulation of two-dimensional interior ballistics model of solid propellant electrothermal-chemical launch with discharge rod plasma generator

    Directory of Open Access Journals (Sweden)

    Yan-jie Ni

    2017-08-01

    Full Text Available Instead of the capillary plasma generator (CPG, a discharge rod plasma generator (DRPG is used in the 30 mm electrothermal-chemical (ETC gun to improve the ignition uniformity of the solid propellant. An axisymmetric two-dimensional interior ballistics model of the solid propellant ETC gun (2D-IB-SPETCG is presented to describe the process of the ETC launch. Both calculated pressure and projectile muzzle velocity accord well with the experimental results. The feasibility of the 2D-IB-SPETCG model is proved. Depending on the experimental data and initial parameters, detailed distribution of the ballistics parameters can be simulated. With the distribution of pressure and temperature of the gas phase and the propellant, the influence of plasma during the ignition process can be analyzed. Because of the radial flowing plasma, the propellant in the area of the DRPG is ignited within 0.01 ms, while all propellant in the chamber is ignited within 0.09 ms. The radial ignition delay time is much less than the axial delay time. During the ignition process, the radial pressure difference is less than 5  MPa at the place 0.025 m away from the breech. The radial ignition uniformity is proved. The temperature of the gas increases from several thousand K (conventional ignition to several ten thousand K (plasma ignition. Compare the distribution of the density and temperature of the gas, we know that low density and high temperature gas appears near the exits of the DRPG, while high density and low temperature gas appears at the wall near the breech. The simulation of the 2D-IB-SPETCG model is an effective way to investigate the interior ballistics process of the ETC launch. The 2D-IB-SPETC model can be used for prediction and improvement of experiments.

  17. Modeling of robotic fish propelled by an ionic polymer-metal composite caudal fin

    Science.gov (United States)

    Chen, Zheng; Shatara, Stephan; Tan, Xiaobo

    2009-03-01

    In this paper, a model is proposed for a biomimetic robotic fish propelled by an ionic polymer metal composite (IPMC) actuator with a rigid passive fin at the end. The model incorporates both IPMC actuation dynamics and the hydrodynamics, and predicts the steady-state speed of the robot under a periodic actuation voltage. Experimental results have shown that the proposed model can predict the fish motion for different tail dimensions. Since its parameters are expressed in terms of physical properties and geometric dimensions, the model is expected to be instrumental in optimal design of the robotic fish.

  18. Determination of the Basis for Temperature Compensation in ETC Ignited Solid Propellant Guns

    National Research Council Canada - National Science Library

    Pesce-Rodriguez, R. A; Beyer, R. A

    2004-01-01

    A series of experiments and reanalysis of previously published results has led to the discovery of the key interaction between the plasma of an electrothermal igniter and the gun propellant in large caliber cannon...

  19. Studies on Decomposition and Combustion Mechanism of Solid Fuel Rich Propellants

    Science.gov (United States)

    2010-08-30

    thrust to cruise at supersonic speed. This was followed by the test of large diameter ramjet called burner test vehicle (BTV). Advanced low volume...propellant surface. Vernekar et al (43) found that in pressed AP-Al pellets , maximum burn rate is obtained at intermediate metal content. Jain et al...conjunction with high pressure window strand burner . They found that the propellant combustion was irregular and regression rate varied from 0.3 to 3

  20. Metallized solid rocket propellants based on AN/AP and PSAN/AP for access to space

    Science.gov (United States)

    Levi, S.; Signoriello, D.; Gabardi, A.; Molinari, M.; Galfetti, L.; Deluca, L. T.; Cianfanelli, S.; Klyakin, G. F.

    2009-09-01

    Solid rocket propellants based on dual mixes of inorganic crystalline oxidizers (ammonium nitrate (AN) and ammonium perchlorate (AP)) with binder and a mixture of micrometric-nanometric aluminum were investigated. Ammonium nitrate is a low-cost oxidizer, producing environment friendly combustion products but with lower specific impulse compared to AP. The better performance obtained with AP and the low quantity of toxic emissions obtained by using AN have suggested an interesting compromise based on a dual mixture of the two oxidizers. To improve the thermal response of raw AN, different types of phase stabilized AN (PSAN) and AN/AP co-crystals were investigated.

  1. Flight Investigation of the Performance of a Two-stage Solid-propellant Nike-deacon (DAN) Meteorological Sounding Rocket

    Science.gov (United States)

    Heitkotter, Robert H

    1956-01-01

    A flight investigation of two Nike-Deacon (DAN) two-stage solid-propellant rocket vehicles indicated satisfactory performance may be expected from the DAN meteorological sounding rocket. Peak altitudes of 356,000 and 350,000 feet, respectively, were recorded for the two flight tests when both vehicles were launched from sea level at an elevation angle of 75 degrees. Performance calculations based on flight-test results show that altitudes between 358,000 feet and 487,000 feet may be attained with payloads varying between 60 pounds and 10 pounds.

  2. Hazard Studies for Solid Propellant Rocket Motors (Etude des Risque pour les Moteurs-Fusees a Propergols Solides)

    Science.gov (United States)

    1990-09-01

    Combustion Through Granulated Propellant to Predict Transition to Detonation," University of Illinois, Urbana . IL, Final Report, October 19"/6-September...Vol). i, p. 258, 15 -1 9) July 1985 (Albuquerque, NM). F. A. Williams. ’Asymptotic Methods in Ignition Theory," Memoria del VII Congreso de Ia Academia

  3. U.S. Army Armament Research, Development and Engineering Center Grain Evaluation Software to Numerically Predict Linear Burn Regression for Solid Propellant Grain Geometries

    Science.gov (United States)

    2017-10-01

    ENGINEERING CENTER GRAIN EVALUATION SOFTWARE TO NUMERICALLY PREDICT LINEAR BURN REGRESSION FOR SOLID PROPELLANT GRAIN GEOMETRIES Brian...distribution is unlimited. AD U.S. ARMY ARMAMENT RESEARCH, DEVELOPMENT AND ENGINEERING CENTER Munitions Engineering Technology Center Picatinny...U.S. ARMY ARMAMENT RESEARCH, DEVELOPMENT AND ENGINEERING CENTER GRAIN EVALUATION SOFTWARE TO NUMERICALLY PREDICT LINEAR BURN REGRESSION FOR SOLID

  4. Composition of municipal solid waste in Denmark

    DEFF Research Database (Denmark)

    Edjabou, Vincent Maklawe Essonanawe; Petersen, Claus; Scheutz, Charlotte

    2014-01-01

    Data for the composition of municipal solid waste is a critical basis for any assessment of waste technologies and waste management systems. The detailed quantification of waste fractions is absolutely needed for a better technological development of waste treatment. The current waste composition...... comparability to characterize municipal solid waste. This methodology was applied to residual waste collected from 1,442 households in three municipalities in Denmark. The main fractions contributing to the residual household waste were food waste and miscellaneous waste. Statistical analysis suggested...... of standardised and commonly accepted waste characterization methodologies, various approaches have been reported in literature. This limits both comparability and applicability of the results. The purpose of this study was to introduce a consistent methodology that reduces uncertainties and ensures data...

  5. Anti-perovskite solid electrolyte compositions

    Science.gov (United States)

    Zhao, Yusheng; Daemen, Luc Louis

    2015-12-26

    Solid electrolyte antiperovskite compositions for batteries, capacitors, and other electrochemical devices have chemical formula Li.sub.3OA, Li.sub.(3-x)M.sub.x/2OA, Li.sub.(3-x)N.sub.x/3OA, or LiCOX.sub.zY.sub.(1-z), wherein M and N are divalent and trivalent metals respectively and wherein A is a halide or mixture of halides, and X and Y are halides.

  6. Solid particle erosion of polymers and composites

    Science.gov (United States)

    Friedrich, K.; Almajid, A. A.

    2014-05-01

    After a general introduction to the subject of solid particle erosion of polymers and composites, the presentation focusses more specifically on the behavior of unidirectional carbon fiber (CF) reinforced polyetheretherketone (PEEK) composites under such loadings, using different impact conditions and erodents. The data were analyzed on the basis of a newly defined specific erosive wear rate, allowing a better comparison of erosion data achieved under various testing conditions. Characteristic wear mechanisms of the CF/PEEK composites consisted of fiber fracture, matrix cutting and plastic matrix deformation, the relative contribution of which depended on the impingement angles and the CF orientation. The highest wear rates were measured for impingement angles between 45 and 60°. Using abrasion resistant neat polymer films (in this case PEEK or thermoplastic polyurethane (TPU) ones) on the surface of a harder substrate (e.g. a CF/PEEK composite plate) resulted in much lower specific erosive wear rates. The use of such polymeric films can be considered as a possible method to protect composite surfaces from damage caused by minor impacts and erosion. In fact, they are nowadays already successfully applied as protections for wind energy rotor blades.

  7. Pulsed plasma solid propellant microthruster for the synchronous meteorological satellite. Task 4: Engineering model fabrication and test report

    Science.gov (United States)

    Guman, W. J. (Editor)

    1972-01-01

    Two flight prototype solid propellant pulsed plasma microthruster propulsion systems for the SMS satellite were fabricated, assembled and tested. The propulsion system is a completely self contained system requiring only three electrical inputs to operate: a 29.4 volt power source, a 28 volt enable signal and a 50 millsec long command fire signal that can be applied at any rate from 50 ppm to 110 ppm. The thrust level can be varied over a range 2.2 to 1 at constant impulse bit amplitude. By controlling the duration of the 28 volt enable either steady state thrust or a series of discrete impulse bits can be generated. A new technique of capacitor charging was implemented to reduce high voltage stress on energy storage capacitors.

  8. A parallel solution-adaptive scheme for predicting multi-phase core flows in solid propellant rocket motors

    International Nuclear Information System (INIS)

    Sachdev, J.S.; Groth, C.P.T.; Gottlieb, J.J.

    2003-01-01

    The development of a parallel adaptive mesh refinement (AMR) scheme is described for solving the governing equations for multi-phase (gas-particle) core flows in solid propellant rocket motors (SRM). An Eulerian formulation is used to described the coupled motion between the gas and particle phases. A cell-centred upwind finite-volume discretization and the use of limited solution reconstruction, Riemann solver based flux functions for the gas and particle phases, and explicit multi-stage time-stepping allows for high solution accuracy and computational robustness. A Riemann problem is formulated for prescribing boundary data at the burning surface. Efficient and scalable parallel implementations are achieved with domain decomposition on distributed memory multiprocessor architectures. Numerical results are described to demonstrate the capabilities of the approach for predicting SRM core flows. (author)

  9. Solid polymer composite electrolytes for PEMFC

    Energy Technology Data Exchange (ETDEWEB)

    Zaidi, S M.J.; Mikhailenko, S D; Kaliaguine, S

    1998-07-01

    Composite electrolyte membranes for fuel cell technology were prepared from solid state proton conductors and polymer binders. The polymers were partially sulfonated and non-sulfonated polysulfone (PS), porous polyetherimide (PEI) and polymethylmethacrylate (PMMA). As proton conductors H-chabazite, tungstophosphoric acid and its Na-salt and non-stoichiometric boron phosphate were employed. All membranes prepared using sulfonated PS as a binder with sulfonation degree higher than 50% were found to be mechanically unstable. They possess however reasonably high conductivity up to 6{times}10{sup {minus}3} S/cm. Introducing the tungstophosphoric acid (TPA) into the nonsulfonated porous PS makes possible to obtain strong and flexible membranes with s=4{times}10{sup {minus}3} S/cm, while use of boron phosphate in that case results in the conductivity of about 10{sup {minus}5} S/cm. Porous PEI impregnated with aqueous solution of TPA retains its original tensile strength and exhibited the conductivity s=2{times}10{sup {minus}4} S/cm. It however fell to 3{times}10{sup {minus}5} S/cm when the binder was modified with 2% of propionic acid, which caused a decrease in polymer pore size. Incorporation of the sodium acid salt of TPA into PEI allows one to obtain a composite with reasonably good mechanical properties and a conductivity of ca 10{sup {minus}5} S/cm for membranes prepared by the cast method. Using the phase inversion technique for preparation of the membranes of the same composition makes possible to increase their conductivity up to 10{sup {minus}4} S/cm. When boron phosphate was used in lieu of TPA salt the conductivity obtained is still higher reaching 3{times}10{sup {minus}5} and 3{times}10{sup {minus}4} S/cm for membranes prepared by cast and phase inversion techniques respectively. The PMMA based membranes were mechanically stable even when a solid content reached 55wt.%. Among PMMA membranes the highest conductivity of 10{sup {minus}3} S/cm was registered for

  10. Trinitromethyl Heterocyclic Oxidizers as a Solid Propellant Ingredient Final Report CRADA No TC02146.0

    Energy Technology Data Exchange (ETDEWEB)

    Pagoria, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Racoveanu, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-08-15

    This was a collaborative effort between Lawrence Livermore National Security, LLC as manager and operator of Lawrence Livermore National Laboratory (LLNL) and Physical Sciences, Inc. (PSI), to develop a synthesis of two novel energetic heterocyclic oxidizers as possible replacements for ammonium perchlorate (AP) in rocket propellant formulations. This CRADA resulted from the award of the Phase I Small Business Technology Transfer (STTR) from DOD. The CRADA consisted of two phases. The goal for Phase 1 was to produce a new oxidizer called TNMDNP. Phase 2 is optional (based on the success of Phase 1) and the goal of Phase 2 (optional) was to produce a new oxidizer called TNMDNT. Phase 2 tasks would be performed based on the successful results of Phase 1.

  11. Evaluation of Flygt Propeller Mixers for Double-Shell Tank (DST) High Level Waste Auxiliary Solids Mobilization

    International Nuclear Information System (INIS)

    PACQUET, E.A.

    2000-01-01

    The River Protection Project (RPP) is planning to retrieve radioactive waste from the single-shell tanks (SST) and double-shell tanks (DST) underground at the Hanford Site. This waste will then be transferred to a waste treatment plant to be immobilized (vitrified) in a stable glass form. Over the years, the waste solids in many of the tanks have settled to form a layer of sludge at the bottom. The thickness of the sludge layer varies from tank to tank, from no sludge or a few inches of sludge to about 15 ft of sludge. The purpose of this technology and engineering case study is to evaluate the Flygt(trademark) submersible propeller mixer as a potential technology for auxiliary mobilization of DST HLW solids. Considering the usage and development to date by other sites in the development of this technology, this study also has the objective of expanding the knowledge base of the Flygt(trademark) mixer concept with the broader perspective of Hanford Site tank waste retrieval. More specifically, the objectives of this study delineated from the work plan are described

  12. Thermal Decomposition Behaviors and Burning Characteristics of AN/RDX-Based Composite Propellants Supplemented with MnO2 and Fe2O3

    Science.gov (United States)

    Kohga, Makoto; Naya, Tomoki

    2015-10-01

    Ammonium nitrate (AN)-based composite propellants have gained popularity because of the clean burning nature of AN as an oxidizer. However, such propellants have several disadvantages such as poor ignition and low burning rate. The burning characteristics of the AN propellant were improved when a portion of this propellant was replaced by an energetic material and the addition of a catalyst. In this study, RDX (1,3,5-trinitroperhydro-1,3,5-triazine) was used as the energetic material, and Fe2O3 and MnO2 were used as catalysts. The burning characteristics of the AN/RDX propellants supplemented with catalysts were investigated, and the effects of the replacement of AN by RDX and the catalyst addition were evaluated.

  13. Solid radiation curable polyene compositions containing liquid polythiols and solid styrene-allyl copolymer based polyenes

    International Nuclear Information System (INIS)

    Morgan, C.R.

    1977-01-01

    Novel styrene-allyl alcohol copolymer based solid polyene compositions which when mixed with liquid polythiols can form solid curable polyene-polythiol systems are claimed. These solid polyenes, containing at least two reactive carbon-to-carbon unsaturated bonds, are urethane or ester derivatives of styrene-allyl alcohol copolymers. The solid polyenes are prepared by treating the hydroxyl groups of a styrene-allyl alcohol copolymer with a reactive unsaturated isocyanate, e.g., allyl isocyanate or a reactive unsaturated carboxylic acid, e.g., acrylic acid. Upon exposure to a free radical generator, e.g., actinic radiation, the solid polyene-polythiol compositions cure to solid, insoluble, chemically resistant, cross-linked polythioether products. Since the solid polyene-liquid polythiol composition can be cured in a solid state, such a curable system finds particular use in preparation of coatings, imaged surfaces such as photoresists, particularly solder-resistant photoresists, printing plates, etc

  14. Solid Propellant Subscale Burning Rate Analysis Methods for US and Selected NATO Facilities

    Science.gov (United States)

    2002-01-01

    impossibility of the center of a particle lying closer than its radius from a solid boundary, * Due to surface tension and sedimentation (tends to level...34 effect (for bottom cast or bayonet cast grains) may consist of sedimentation of larger particles against the walls during casting flow, with the...February 2000. 91 Ratti A., "Metodi di Riduzione Dati Balistici per i Boosters a Propellente Solido di Ariane-4 e di Ariane-5," M.Sc. Thesis in Aerospace

  15. Finite element implementation of a thermo-damage-viscoelastic constitutive model for hydroxyl-terminated polybutadiene composite propellant

    Science.gov (United States)

    Xu, Jinsheng; Han, Long; Zheng, Jian; Chen, Xiong; Zhou, Changsheng

    2017-11-01

    A thermo-damage-viscoelastic model for hydroxyl-terminated polybutadiene (HTPB) composite propellant with consideration for the effect of temperature was implemented in ABAQUS. The damage evolution law of the model has the same form as the crack growth equation for viscoelastic materials, and only a single damage variable S is considered. The HTPB propellant was considered as an isotropic material, and the deviatoric and volumetric strain-stress relations are decoupled and described by the bulk and shear relaxation moduli, respectively. The stress update equations were expressed by the principal stresses σ_{ii}R and the rotation tensor M, the Jacobian matrix in the global coordinate system J_{ijkl} was obtained according to the fourth-order tensor transformation rules. Two models having complex stress states were used to verify the accuracy of the constitutive model. The test results showed good agreement with the strain responses of characteristic points measured by a contactless optical deformation test system, which illustrates that the thermo-damage-viscoelastic model perform well at describing the mechanical properties of an HTPB propellant.

  16. Study on Design of High Efficiency and Light Weight Composite Propeller Blade for a Regional Turboprop Aircraft

    Science.gov (United States)

    Kong, Changduk; Lee, Kyungsun

    2013-03-01

    In this study, aerodynamic and structural design of the composite propeller blade for a regional turboprop aircraft is performed. The thin and wide chord propeller blade of high speed turboprop aircraft should have proper strength and stiffness to carry various kinds of loads such as high aerodynamic bending and twisting moments and centrifugal forces. Therefore the skin-spar-foam sandwich structure using high strength and stiffness carbon/epoxy composite materials is used to improve the lightness. A specific design procedure is proposed in this work as follows; firstly the aerodynamic configuration design, which is acceptable for the design requirements, is carried out using the in-house code developed by authors, secondly the structure design loads are determined through the aerodynamic load case analysis, thirdly the spar flange and the skin are preliminarily sized by consideration of major bending moments and shear forces using both the netting rule and the rule of mixture, and finally, the stress analysis is performed to confirm the structural safety and stability using finite element analysis commercial code, MSC. NASTRAN/PATRAN. Furthermore the additional analysis is performed to confirm the structural safety due to bird strike impact on the blade during flight operation using a commercial code, ANSYS. To realize the proposed propeller design, the prototype blades are manufactured by the following procedure; the carbon/epoxy composite fabric prepregs are laid up for skin and spar on a mold using the hand lay-up method and consolidated with a proper temperature and vacuum in the oven. To finalize the structural design, the full-scale static structural test is performed under the simulated aerodynamic loads using 3 point loading method. From the experimental results, it is found that the designed blade has a good structural integrity, and the measured results agree well with the analytical results as well.

  17. Simple-1: Development stage of the data transmission system for a solid propellant mid-power rocket model

    Science.gov (United States)

    Yarce, Andrés; Sebastián Rodríguez, Juan; Galvez, Julián; Gómez, Alejandro; García, Manuel J.

    2017-06-01

    This paper presents the development stage of a communication module for a solid propellant mid-power rocket model. The communication module was named. Simple-1 and this work considers its design, construction and testing. A rocket model Estes Ventris Series Pro II® was modified to introduce, on the top of the payload, several sensors in a CanSat form factor. The Printed Circuit Board (PCB) was designed and fabricated from Commercial Off The Shelf (COTS) components and assembled in a cylindrical rack structure similar to this small format satellite concept. The sensors data was processed using one Arduino Mini and transmitted using a radio module to a Software Defined Radio (SDR) HackRF based platform on the ground station. The Simple-1 was tested using a drone in successive releases, reaching altitudes from 200 to 300 meters. Different kind of data, in terms of altitude, position, atmospheric pressure and vehicle temperature were successfully measured, making possible the progress to a next stage of launching and analysis.

  18. Determining solid-fluid interface temperature distribution during phase change of cryogenic propellants using transient thermal modeling

    Science.gov (United States)

    Bellur, K.; Médici, E. F.; Hermanson, J. C.; Choi, C. K.; Allen, J. S.

    2018-04-01

    Control of boil-off of cryogenic propellants is a continuing technical challenge for long duration space missions. Predicting phase change rates of cryogenic liquids requires an accurate estimation of solid-fluid interface temperature distributions in regions where a contact line or a thin liquid film exists. This paper described a methodology to predict inner wall temperature gradients with and without evaporation using discrete temperature measurements on the outer wall of a container. Phase change experiments with liquid hydrogen and methane in cylindrical test cells of various materials and sizes were conducted at the Neutron Imaging Facility at the National Institute of Standards and Technology. Two types of tests were conducted. The first type of testing involved thermal cycling of an evacuated cell (dry) and the second involved controlled phase change with cryogenic liquids (wet). During both types of tests, temperatures were measured using Si-diode sensors mounted on the exterior surface of the test cells. Heat is transferred to the test cell by conduction through a helium exchange gas and through the cryostat sample holder. Thermal conduction through the sample holder is shown to be the dominant mode with the rate of heat transfer limited by six independent contact resistances. An iterative methodology is employed to determine contact resistances between the various components of the cryostat stick insert, test cell and lid using the dry test data. After the contact resistances are established, inner wall temperature distributions during wet tests are calculated.

  19. Prilling and Coating of Ammonium Dinitramide (ADN Solid Green Propellant in Toluene Mixture Using Ultrasound Sonication

    Directory of Open Access Journals (Sweden)

    Asad Rahman

    2018-03-01

    Full Text Available Ammonium Dinitramide (ADN in its generic form has a long needle shaped structure, which hinders higher solid loading. Therefore, it is of utmost importance to optimize its crystal morphology into octagonal shapes. Moreover, the low critical humidity level of ADN renders it unusable in a humid climate. Hence, encapsulation with a hydrophobic polymer is necessary. In the present work, ADN was synthesized by nitration of potassium sulfamate with mixed acid nitration. The product was then mixed with toluene, graphene, citryl ammonium butyl, Cab-o-sil, and coating polymer (Polystyrene or HTPB and treated with ultrasound to obtain semi-spherical ADN-coated particles. The method offers a reduction in operating temperature and elimination of ADN melting in the shape-altering process. In addition, the ADN product has a similar particle size and thermal stability compared to those in a conventional ADN melt-prilling method. The ADN product investigated under SEM confirms the particle morphological change from long needles into semi-spherical shapes. The particle size obtained, in the micrometer range, is ideal for higher theoretical maximum density. Furthermore, the ultrasound-treated ADN particles show significant reduction in moisture absorption, from 68% to 16% at 65% relative humidity. The DSC result shows no degradation of thermal stability of the coated particles.

  20. Operating instabilities in big solid propellant engines; Instabilites de fonctionnement dans les moteurs a propergol solide de grande taille

    Energy Technology Data Exchange (ETDEWEB)

    Gallier, S.; Guery, J.F.; Godfroy, F. [Groupe SNPE Propulsion/ Centre de Recherches du Boucher, 91 - Vert le Petit (France); Lebreton, P.; Ribereau, D.; Cloutet, P. [Groupe SNPE Propulsion, 33 - Medard en Jalles (France)

    2002-09-01

    Some solid rocket motors (SRM) may exhibit instabilities during operation. Different kind of instabilities ore liable to occur depending on size or operating conditions. In extreme cases, instabilities may involve overage pressure shift sometimes leading to motor failure. In large SRM's, such as the ones used for space or strategic propulsion, instabilities become apparent as a thrust oscillation implying vibrations which can turn out to be severe for carrying load. In any cases, instabilities are unwanted and should be predicted as early as conception. Active research on instabilities on large SRM's showed they are dominated by some coupling between chamber acoustics and hydrodynamic instability. The latter arises from some vortex shedding stemming either from surface instability or unstable shear layers. Earlier, predictions were based on theoretical developments such as linear acoustic balance. Although still in use for a rough estimation, this approach has progressively been replaced by numerical simulations which now show supremacy for tackling complex geometries or flow patterns. However, simulations need to use adapted schemes and must also be assessed by numerous validations. This validation step is crucial to insure quality and trust for CFD. Indeed the flow inside an actual motor involves complex physics and only pressure is measured due to severe ambient conditions- Hence, CFD is often the only way to get an insight into the flow validation procedure is sustained by experimental data obtained either in large scale motors sub-scale motors or cold flow sub-scale facility. Cold flow experiments make the opportunity to use advanced measurement techniques (such as Laser Doppler Velocimetry or Particle Image Velocimetry) and contribute to enhanced validations, although the flow may differ from an actual motor flow. However, there is still some work left to bring CFD to a reliable prediction tool able to deal with arbitrary geometry or operating

  1. Composite hydrogen-solid methane moderators

    International Nuclear Information System (INIS)

    Picton, D.; Bennington, S.; Ansell, S.; Fernandez-Garcia, J.; Broome, T.

    2004-01-01

    This paper describes the results of Monte-Carlo calculations for a coupled moderator on a low-power pulsed neutron spallation source and is part of the design study for a second target station for the ISIS spallation source. Various options were compared including hydrogen, solid methane, grooving the solid methane and compound moderators made of hydrogen in front of solid methane. To maximise the neutron current at low energies two strategies appear to emerge from the calculations. For instruments that view a large area of moderator surface a layer of hydrogen in front of a thin solid-methane moderator is optimum, giving a gain of about a factor 10 relative to the current liquid hydrogen moderator on the existing ISIS tantalum target. For instruments that only view a restricted area higher flux, corresponding to a gain of 13.5, can be achieved with the use of a single groove or re-entrant hole in the moderator. (orig.)

  2. Effective medium of periodic fluid-solid composites

    KAUST Repository

    Mei, Jun; Wu, Ying; Liu, Zhengyou

    2012-01-01

    An analytic solution of the effective mass density and bulk modulus of a periodic fluid-solid composite is obtained by using the multiple-scattering theory in the long-wavelength limit. It is shown that when the concentration of solid inclusions

  3. Development and Characterization of a Novel Additive Manufacturing Technology Capable of Printing Propellants with High Solids Loadings

    Data.gov (United States)

    National Aeronautics and Space Administration — Ever since rockets have been around, there has been a demand to improve propulsion systems by increasing propellant performance in order to reduce production time...

  4. A Local Composition Model for Paraffinic Solid Solutions

    DEFF Research Database (Denmark)

    Coutinho, A.P. João; Knudsen, Kim; Andersen, Simon Ivar

    1996-01-01

    The description of the solid-phase non-ideality remains the main obstacle in modelling the solid-liquid equilibrium of hydrocarbons. A theoretical model, based on the local composition concept, is developed for the orthorhombic phase of n-alkanes and tested against experimental data for binary sy...... systems. It is shown that it can adequately predict the experimental phase behaviour of paraffinic mixtures. This work extends the applicability of local composition models to the solid phase. Copyright (C) 1996 Elsevier Science Ltd....

  5. Investigation of the NACA 4-(3)(8)-045 Two-blade Propellers at Forward Mach Numbers to 0.725 to Determine the Effects of Compressibility and Solidity on Performance

    Science.gov (United States)

    Stack, John; Draley, Eugene C; Delano, James B; Feldman, Lewis

    1950-01-01

    As part of a general investigation of propellers at high forward speeds, tests of two 2-blade propellers having the NACA 4-(3)(8)-03 and NACA 4-(3)(8)-45 blade designs have been made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 60 degrees for forward Mach numbers from 0.165 to 0.725 to establish in detail the changes in propeller characteristics due to compressibility effects. These propellers differed primarily only in blade solidity, one propeller having 50 percent and more solidity than the other. Serious losses in propeller efficiency were found as the propeller tip Mach number exceeded 0.91, irrespective of forward speed or blade angle. The magnitude of the efficiency losses varied from 9 percent to 22 percent per 0.1 increase in tip Mach number above the critical value. The range of advance ratio for peak efficiency decreased markedly with increase of forward speed. The general form of the changes in thrust and power coefficients was found to be similar to the changes in airfoil lift coefficient with changes in Mach number. Efficiency losses due to compressibility effects decreased with increase of blade width. The results indicated that the high level of propeller efficiency obtained at low speeds could be maintained to forward sea-level speeds exceeding 500 miles per hour.

  6. Solid polymer electrolyte composite membrane comprising laser micromachined porous support

    Science.gov (United States)

    Liu, Han [Waltham, MA; LaConti, Anthony B [Lynnfield, MA; Mittelsteadt, Cortney K [Natick, MA; McCallum, Thomas J [Ashland, MA

    2011-01-11

    A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a rigid, non-electrically-conducting support, the support preferably being a sheet of polyimide having a thickness of about 7.5 to 15 microns. The support has a plurality of cylindrical pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores, which preferably have a diameter of about 5 microns, are made by laser micromachining and preferably are arranged in a defined pattern, for example, with fewer pores located in areas of high membrane stress and more pores located in areas of low membrane stress. The pores are filled with a first solid polymer electrolyte, such as a perfluorosulfonic acid (PFSA) polymer. A second solid polymer electrolyte, which may be the same as or different than the first solid polymer electrolyte, may be deposited over the top and/or bottom of the first solid polymer electrolyte.

  7. Investigation of the interfacial bonding in composite propellants. 1,3,5-Trisubstituted isocyanurates as universal bonding agents

    Directory of Open Access Journals (Sweden)

    GORDANA S. USCUMLIC

    2006-05-01

    Full Text Available A series of 1,3,5-trisubstituted isocyanurates (substituents: CH2CH2OH, CH2CH=CH2 and CH2CH2COOH was synthesized according to a modified literature procedure. Experimental investigations included modification of the synthetic procedure in terms of the starting materials, solvents, temperature, isolation techniques, as well as purification and identification of the products. All the synthesized isocyanurates were identified by their melting point and FTIR, 1H NMR and UV spectroscopic data. Fourier transform infrared spectrophotometry was also used to study the interaction between ammonium perchlorate, hydroxyl terminated poly(butadiene, carboxyl terminated poly(butadiene, poly(butadiene-co-acrylonitrile, poly(propylene ether, cyclotrimethylenetrinitramine and the compounds synthesized in this work, which can serve as bonding agents. The results show that tris(2-hydroxyethylisocyanurate is a universal bonding agent for the ammonium perchlorate/carboxyl terminated poly(butadiene/cyclotrimethylenetrinitramine composite propellant system.

  8. Features of solid solutions composition in magnesium with yttrium alloys

    International Nuclear Information System (INIS)

    Drits, M.E.; Rokhlin, L.L.; Tarytina, I.E.

    1983-01-01

    Additional data on features of yttrium solid solutions composition in magnesium in the course of their decomposition investigation in the case of aging are obtianed. The investigation has been carried out on the base of a binary magnesium-yttrium alloy the composition of which has been close to maximum solubility (at eutectic temperature) and magnesium-yttrium alloys additionally doped with zinc. It is shown that higher yttrium solubility in solid magnesium than it has been expected, issueing from the difference in atomic radii of these metals indicates electron yttrium-magnesium atoms interaction. In oversaturated magnesium-yttrium solid solutions at earlier decomposition stages Mg 3 Cd type ordering is observed. At aging temperatures up to 250 deg C and long exposures corresponding to highest strengthening in oversaturated magnesium yttrium solid solutions a rhombic crystal lattice phase with three symmetric orientations is formed

  9. Heat transfer in heterogeneous propellant combustion systems

    International Nuclear Information System (INIS)

    Brewster, M.Q.

    1992-01-01

    This paper reports that heat transfer plays an important role in several critical areas of heterogeneous, solid-propellant combustion systems. These areas include heat feedback to the propellant surface, heat transfer between burning aluminum droplets and their surroundings, heat transfer to internal insulation systems, and heat transfer to aft-end equipment. Gas conduction dominates heat feedback to the propellant surface in conventional ammonium perchlorate (AP) composite propellants, although particle radiative feedback also plays a significant role in combustion of metalized propellants. Particle radiation plays a dominant role in heat transfer to internal insulation, compared with that of convection. However, conduction by impingement of burning aluminum particles, which has not been extensively studied, may also be significant. Radiative heat loss plays an important role in determining the burning rate of molten aluminum particles due to a highly luminous, oxide particle-laden, detached flame envelope. Radiation by aluminum oxide smoke particles also plays a dominant role in heat transfer from the exhaust plume to aft-end equipment. Uncertainties in aluminum oxide particle-size distribution and optical properties still make it difficult to predict radiative plume heat transfer accurately from first principles

  10. Composition of municipal solid waste in Denmark

    DEFF Research Database (Denmark)

    Edjabou, Maklawe Essonanawe

    In response to continuous pressure on resources, and the requirement for secure and sustainable consumption, public authorities are pushing the efficient use of resources. Among other initiatives, the prevention, reduction and recycling of solid waste have been promoted. In this context, reliable...... data for the material and resource content of waste flows are crucial to establishing baselines, setting targets and tracking progress on waste prevention, reduction and recycling goals. Waste data are also a critical basis for the planning, development and environmental assessment of technologies...... the comparison of waste data with various objectives. Analysis revealed that Danish residual household waste constitutes mainly food waste (42 – 45% mass per wet basis). Misplaced recyclable materials in residual waste bins, such as paper, board, glass, metal and plastic, amounted to 20% (mass per wet basis...

  11. Nonmetallic and composite materials as solid superleaks

    International Nuclear Information System (INIS)

    Goldschvartz, J.M.

    1982-01-01

    This chapter discusses the devices in general solid porous materials in which the so-called diameter of the pores, gaps, inter-crystalline spaces, or small channels, etc, are equal or smaller than 100 0 A. Examines silicon carbide, wonderstone, talc-stone, rocks as superleaks, magnetic superleaks, the onset point of a superleak, determination of the onset point, and some applications of superleaks (as a filter, as an isotope separator, as a separator in the 3 He- 4 He dilution refrigerator, in a vortex refrigerator, in a servo-valve for liquid helium two (the cocatron), method of measuring the size of sub-microscopic pores, ultra cold neutrons, superconductors pressed into porous materials)

  12. Tribo-electric charging of dielectric solids of identical composition

    Science.gov (United States)

    Angus, John C.; Greber, Isaac

    2018-05-01

    Despite its long history and importance in many areas of science and technology, there is no agreement on the mechanisms responsible for tribo-electric charging, including especially the tribo-charging of chemically identical dielectric solids. Modeling of the excitation, diffusional transport, and de-excitation of electrons from hot spots shows that a difference in local surface roughness of otherwise identical solid dielectric objects leads to different transient excited electron concentrations during tribo-processes. The model predicts that excited electron concentrations are lower and concentration gradients higher in solids with rougher rather than smoother surfaces. Consequently, during contact, the flux of charge carriers (electrons or holes) from hot spots will be greater into the rougher solid than into the smoother solid. These predictions are in agreement with current and historical observations of tribo-electric charge transfer between solids of the same composition. This effect can take place in parallel with other processes and may also play a role in the charging of solids of different composition.

  13. Zinc composite anode for batteries with solid electrolyte

    Science.gov (United States)

    Tedjar, F.; Melki, T.; Zerroual, L.

    A new negative composite anode for batteries with a solid electrolyte is studied. Using a complex of zinc ammonium chloride mixed with zinc metal powder, the advantage of the Zn/Zn 2+ electrode ( e = -760 mV) is kept while the energy density and the shelf-life of the battery are increased.

  14. Zinc composite anode for batteries with solid electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Tedjar, F.; Melki, T.; Zerroual, L. (Setif Univ. (Algeria). Unite de Recherche Electrochimie)

    1992-05-01

    A new negative composite anode for batteries with a solid electrolyte is studied. Using a complex of zinc ammonium chloride mixed with zinc metal powder, the advantage of the Zn/Zn[sup 2+] electrode (e = -760 mV) is kept while the energy density and the shelf-life of the battery are increased. (orig.).

  15. Nutritional composition of bioproducts generated from semi-solid ...

    African Journals Online (AJOL)

    Nutritional composition of bioproducts generated from semi-solid fermentation of pineapple peel by edible mushrooms. Raiane Áila Teixeira Souza, Tamiris Rio Branco da Fonseca, Larissa de Souza Kirsch, Larissa Svetlana Cavalcante Silva, Mircella Marialva Alecrim, Raimundo Felipe da Cruz Filho, Maria Francisca ...

  16. Gamma camera system with composite solid state detector

    International Nuclear Information System (INIS)

    Gerber, M.S.; Miller, D.W.

    1977-01-01

    A composite solid-state detector is described for utilization within gamma cameras. The detector's formed of an array of detector crystals, the opposed surfaces of each of which are formed incorporating an impedance-derived configuration for determining one coordinate of the location of discrete impinging photons upon the detector. A combined read-out for all detectors within the composite array is achieved through a row and column interconnection of the impedance configurations. Utilizing the read-outs for respective sides of the discrete crystals, a resultant time-constant characteristic for the composite detector crystal array remains essentially that of individual crystal detectors

  17. Analysis of semi-solid processing for metal matrix composite synthesis using factorial design

    Directory of Open Access Journals (Sweden)

    Kratus Ranieri

    2012-02-01

    Full Text Available The main goal in this work is to conduct a quantitative analysis of the mechanical stir casting process for obtaining particulate metal matrix composites. A combined route of stirring at semi-solid state followed by stirring at liquid state is proposed. A fractional factorial design was developed to investigate the influence and interactions of factors as: time, rotation, initial fraction and particle size, on the incorporated fraction. The best incorporations were obtained with all factors at high levels, as well as that very long stirring periods have no strong influence being particle size and rotation the most important factors on the incorporated fraction. Particle wetting occurs during stirring at semi-solid state, highlighting the importance of the interactions between particles and the alloy globularized phase. The role of the alloying element Mg as a wettability-promoting agent is discussed. The shear forces resulting from the stirring system is emphasized and understood as the effect of rotation itself added to the propeller blade geometry.

  18. Solid oxide fuel cell having a glass composite seal

    Science.gov (United States)

    De Rose, Anthony J.; Mukerjee, Subhasish; Haltiner, Jr., Karl Jacob

    2013-04-16

    A solid oxide fuel cell stack having a plurality of cassettes and a glass composite seal disposed between the sealing surfaces of adjacent cassettes, thereby joining the cassettes and providing a hermetic seal therebetween. The glass composite seal includes an alkaline earth aluminosilicate (AEAS) glass disposed about a viscous glass such that the AEAS glass retains the viscous glass in a predetermined position between the first and second sealing surfaces. The AEAS glass provides geometric stability to the glass composite seal to maintain the proper distance between the adjacent cassettes while the viscous glass provides for a compliant and self-healing seal. The glass composite seal may include fibers, powders, and/or beads of zirconium oxide, aluminum oxide, yttria-stabilized zirconia (YSZ), or mixtures thereof, to enhance the desirable properties of the glass composite seal.

  19. Solid polymer electrolyte composite membrane comprising plasma etched porous support

    Science.gov (United States)

    Liu, Han; LaConti, Anthony B.

    2010-10-05

    A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a rigid, non-electrically-conducting support, the support preferably being a sheet of polyimide having a thickness of about 7.5 to 15 microns. The support has a plurality of cylindrical pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores, which preferably have a diameter of about 0.1 to 5 microns, are made by plasma etching and preferably are arranged in a defined pattern, for example, with fewer pores located in areas of high membrane stress and more pores located in areas of low membrane stress. The pores are filled with a first solid polymer electrolyte, such as a perfluorosulfonic acid (PFSA) polymer. A second solid polymer electrolyte, which may be the same as or different than the first solid polymer electrolyte, may be deposited over the top and/or bottom of the first solid polymer electrolyte.

  20. Parameters Affecting the Erosive Burning of Solid Rocket Motor

    OpenAIRE

    Abdelaziz Almostafa; Guozhu Liang; Elsayed Anwer

    2018-01-01

    Increasing the velocity of gases inside solid rocket motors with low port-to-throat area ratios, leading to increased occurrence and severity of burning rate augmentation due to flow of propellant products across burning propellant surfaces (erosive burning), erosive burning of high energy composite propellant was investigated to supply rocket motor design criteria and to supplement knowledge of combustion phenomena, pressure, burning rate and high velocity of gases all of these are parameter...

  1. Investigation of a nanoconfined, ceramic composite, solid polymer electrolyte

    International Nuclear Information System (INIS)

    Jayasekara, Indumini; Poyner, Mark; Teeters, Dale

    2017-01-01

    The challenges for further development of lithium rechargeable batteries are finding electrolyte materials that are safe, have mechanical and thermal stability and have sufficiently high ionic conduction. Polymer electrolytes have many of these advantages, but suffer with low ionic conduction. This study involves the use of anodic aluminum oxide (AAO) membranes having nanochannels filled with polymer electrolyte to make composite solid electrolytes having ionic conductivity several orders of magnitude higher (10 −4 Ω ‐1 cm −1 ) than non-confined polymer. SEM, ac impedance spectroscopy, temperature dependence studies, XRD, ATR- FTIR and DSC studies were done in order to characterize and understand the behavior of nanoconfined polymer electrolytes. The composite polymer electrolyte was found to be more amorphous with polymer chains aligned in the direction of the nanochannels, which is felt to promote ion conduction. The electrolyte systems, confined in nanoporous membranes, can be used as electrolytes for the fabrication of a room temperature all solid state battery.

  2. Anodic stripping voltammetry using graphite composite solid electrode

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Tomáš; Barek, J.; Kopanica, Miloslav

    2009-01-01

    Roč. 74, 11-12 (2009), s. 1807-1826 ISSN 0010-0765 R&D Projects: GA AV ČR IAA400400806; GA ČR GA203/07/1195; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z40400503 Keywords : Graphite composite solid electrode * voltammetry * metals Subject RIV: CG - Electrochemistry Impact factor: 0.856, year: 2009

  3. Hybrids - Best of both worlds. [liquid and solid propellants mated for safe reliable and low cost launch vehicles

    Science.gov (United States)

    Goldberg, Ben E.; Wiley, Dan R.

    1991-01-01

    An overview is presented of hybrid rocket propulsion systems whereby combining solids and liquids for launch vehicles could produce a safe, reliable, and low-cost product. The primary subsystems of a hybrid system consist of the oxidizer tank and feed system, an injector system, a solid fuel grain enclosed in a pressure vessel case, a mixing chamber, and a nozzle. The hybrid rocket has an inert grain, which reduces costs of development, transportation, manufacturing, and launch by avoiding many safety measures that must be taken when operating with solids. Other than their use in launch vehicles, hybrids are excellent for simulating the exhaust of solid rocket motors for material development.

  4. New Propellants and Cryofuels

    Science.gov (United States)

    Palasezski, Bryan; Sullivan, Neil S.; Hamida, Jaha; Kokshenev, V.

    2006-01-01

    The proposed research will investigate the stability and cryogenic properties of solid propellants that are critical to NASA s goal of realizing practical propellant designs for future spacecraft. We will determine the stability and thermal properties of a solid hydrogen-liquid helium stabilizer in a laboratory environment in order to design a practical propellant. In particular, we will explore methods of embedding atomic species and metallic nano-particulates in hydrogen matrices suspended in liquid helium. We will also measure the characteristic lifetimes and diffusion of atomic species in these candidate cryofuels. The most promising large-scale advance in rocket propulsion is the use of atomic propellants; most notably atomic hydrogen stabilized in cryogenic environments, and metallized-gelled liquid hydrogen (MGH) or densified gelled hydrogen (DGH). The new propellants offer very significant improvements over classic liquid oxygen/hydrogen fuels because of two factors: (1) the high energy-release, and (ii) the density increase per unit energy release. These two changes can lead to significant reduced mission costs and increased payload to orbit weight ratios. An achievable 5 to 10 percent improvement in specific impulse for the atomic propellants or MGH fuels can result in a doubling or tripling of system payloads. The high-energy atomic propellants must be stored in a stabilizing medium such as solid hydrogen to inhibit or delay their recombination into molecules. The goal of the proposed research is to determine the stability and thermal properties of the solid hydrogen-liquid helium stabilizer. Magnetic resonance techniques will be used to measure the thermal lifetimes and the diffusive motions of atomic species stored in solid hydrogen grains. The properties of metallic nano-particulates embedded in hydrogen matrices will also be studied and analyzed. Dynamic polarization techniques will be developed to enhance signal/noise ratios in order to be able to

  5. Effect of Fe{sub 2}O{sub 3} in Fe{sub 2}O{sub 3}/AP composite particles on thermal decomposition of AP and on burning rate of the composite propellant

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhenye [National Special Superfine Powder Engineering Research Center, Nanjing University of Science and Technology, Nanjing, 210094 (China); Nanjing University of Technology, Nanjing (China); Li, Fengsheng; Bai, Huaping [National Special Superfine Powder Engineering Research Center, Nanjing University of Science and Technology, Nanjing, 210094 (China)

    2006-12-15

    A technique of composite processing of Fe{sub 2}O{sub 3} and ammonium perchlorate (AP) was employed in making the propellant. The effects of composite processing of Fe{sub 2}O{sub 3} on catalytic activity, on the thermal decomposition of AP, and on the burning rate of the composite propellant were investigated in this paper. Fe{sub 2}O{sub 3}/AP composite particles were prepared by a novel solvent-nonsolvent method. The results show that AP is successfully coated on the surface of Fe{sub 2}O{sub 3}. Composite processing of Fe{sub 2}O{sub 3} and AP can improve the catalytic activity of Fe{sub 2}O{sub 3}. Fe{sub 2}O{sub 3} exhibits better catalytic effect with increasing Fe{sub 2}O{sub 3} content. The larger interface between Fe{sub 2}O{sub 3} and AP and lower density of composite propellant (with the added Fe{sub 2}O{sub 3}/AP composite particles) are responsible for the enhancement of the catalytic activity of Fe{sub 2}O{sub 3}. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  6. Hybrid Composite Material and Solid Particle Erosion Studies

    Science.gov (United States)

    Chellaganesh, D.; Khan, M. Adam; Ashif, A. Mohamed; Ragul Selvan, T.; Nachiappan, S.; Winowlin Jappes, J. T.

    2018-04-01

    Composite is one of the predominant material for most challenging engineering components. Most of the components are in the place of automobile structure, aircraft structures, and wind turbine blade and so on. At the same all the components are indulged to mechanical loading. Recent research on composite material are machinability, wear, tear and corrosion studies. One of the major issue on recent research was solid particle air jet erosion. In this paper hybrid composite material with and without filler. The fibre are in the combination of hemp – kevlar (60:40 wt.%) as reinforcement using epoxy as a matrix. The natural material palm and coconut shell are used as filler materials in the form of crushed powder. The process parameter involved are air jet velocity, volume of erodent and angle of impingement. Experiment performed are in eight different combinations followed from 2k (k = 3) factorial design. From the investigation surface morphology was studied using electron microscope. Mass change with respect to time are used to calculate wear rate and the influence of the process parameters. While solid particle erosion the hard particle impregnates in soft matrix material. Influence of filler material has reduced the wear and compared to plain natural composite material.

  7. Effective medium of periodic fluid-solid composites

    KAUST Repository

    Mei, Jun

    2012-05-24

    An analytic solution of the effective mass density and bulk modulus of a periodic fluid-solid composite is obtained by using the multiple-scattering theory in the long-wavelength limit. It is shown that when the concentration of solid inclusions is high, the effective mass density is structure dependent and differs significantly from the leading-order dipole solution, whereas Wood\\'s formula is accurately valid, independently of the structures. Numerical evaluations from the analytic solution are shown to be in excellent agreement with finite-element simulations. In the vicinity of the tight-packing limit, the critical behavior of the effective mass density is also studied and it is independent of the lattice symmetry. © 2012 Europhysics Letters Association.

  8. Glass/Ceramic Composites for Sealing Solid Oxide Fuel Cells

    Science.gov (United States)

    Bansal, Narottam P.; Choi, Sung R.

    2007-01-01

    A family of glass/ceramic composite materials has been investigated for use as sealants in planar solid oxide fuel cells. These materials are modified versions of a barium calcium aluminosilicate glass developed previously for the same purpose. The composition of the glass in mole percentages is 35BaO + 15CaO + 5Al2O3 + 10B2O3 + 35SiO2. The glass seal was found to be susceptible to cracking during thermal cycling of the fuel cells. The goal in formulating the glass/ ceramic composite materials was to (1) retain the physical and chemical advantages that led to the prior selection of the barium calcium aluminosilicate glass as the sealant while (2) increasing strength and fracture toughness so as to reduce the tendency toward cracking. Each of the composite formulations consists of the glass plus either of two ceramic reinforcements in a proportion between 0 and 30 mole percent. One of the ceramic reinforcements consists of alumina platelets; the other one consists of particles of yttria-stabilized zirconia wherein the yttria content is 3 mole percent (3YSZ). In preparation for experiments, panels of the glass/ceramic composites were hot-pressed and machined into test bars.

  9. A lumped model for rotational modes in periodic solid composites

    KAUST Repository

    Peng, Pai; Asiri, Sharefa M.; Zhang, Xiujuan; Li, Yan; Wu, Ying

    2013-01-01

    We present a lumped model to study the rotational modes in a type of two-dimensional periodic solid composites comprised of a square array of rubber-coated steel cylinders embedded in an epoxy matrix. The model captures the physical essence of rotational modes in such systems for various combinations of material parameters, and, therefore it is able to describe the transition behaviour when the system is gradually adjusted from an elastic metamaterial to an elastic phononic crystal. From the model, we can define a transition zone which separates the typical elastic metamaterials and the phononic crystals.

  10. A lumped model for rotational modes in periodic solid composites

    KAUST Repository

    Peng, Pai

    2013-10-01

    We present a lumped model to study the rotational modes in a type of two-dimensional periodic solid composites comprised of a square array of rubber-coated steel cylinders embedded in an epoxy matrix. The model captures the physical essence of rotational modes in such systems for various combinations of material parameters, and, therefore it is able to describe the transition behaviour when the system is gradually adjusted from an elastic metamaterial to an elastic phononic crystal. From the model, we can define a transition zone which separates the typical elastic metamaterials and the phononic crystals.

  11. Innovative boron nitride-doped propellants

    Directory of Open Access Journals (Sweden)

    Thelma Manning

    2016-04-01

    Full Text Available The U.S. military has a need for more powerful propellants with balanced/stoichiometric amounts of fuel and oxidants. However, balanced and more powerful propellants lead to accelerated gun barrel erosion and markedly shortened useful barrel life. Boron nitride (BN is an interesting potential additive for propellants that could reduce gun wear effects in advanced propellants (US patent pending 2015-026P. Hexagonal boron nitride is a good lubricant that can provide wear resistance and lower flame temperatures for gun barrels. Further, boron can dope steel, which drastically improves its strength and wear resistance, and can block the formation of softer carbides. A scalable synthesis method for producing boron nitride nano-particles that can be readily dispersed into propellants has been developed. Even dispersion of the nano-particles in a double-base propellant has been demonstrated using a solvent-based processing approach. Stability of a composite propellant with the BN additive was verified. In this paper, results from propellant testing of boron nitride nano-composite propellants are presented, including closed bomb and wear and erosion testing. Detailed characterization of the erosion tester substrates before and after firing was obtained by electron microscopy, inductively coupled plasma and x-ray photoelectron spectroscopy. This promising boron nitride additive shows the ability to improve gun wear and erosion resistance without any destabilizing effects to the propellant. Potential applications could include less erosive propellants in propellant ammunition for large, medium and small diameter fire arms.

  12. Process for the leaching of AP from propellant

    Science.gov (United States)

    Shaw, G. C.; Mcintosh, M. J. (Inventor)

    1980-01-01

    A method for the recovery of ammonium perchlorate from waste solid rocket propellant is described wherein shredded particles of the propellant are leached with an aqueous leach solution containing a low concentration of surface active agent while stirring the suspension.

  13. Supercritical Fluid Processing of Propellant Polymers

    Science.gov (United States)

    1991-01-01

    of insoluble material present in the polymeric neopentyl glycol azelate (NPGA) binder. Laub (2) summarizes (from Refs 3 & 4) the various polymeric...binders used in composite propellant formulations for DOD missile systems. e.g., these include: polyneopentyl glycol azelate (NPGA) in HAWK. hydroxy...systems. Composite smokeless propellants containing polyethylene glycol (PEG), polyethylene glycol adepate (PEGA) and polycaprolactone are currently under

  14. Characteristics of a non-volatile liquid propellant in liquid-fed ablative pulsed plasma thrusters

    Science.gov (United States)

    Ling, William Yeong Liang; Schönherr, Tony; Koizumi, Hiroyuki

    2017-02-01

    In the past several decades, the use of electric propulsion in spacecraft has experienced tremendous growth. With the increasing adoption of small satellites in the kilogram range, suitable propulsion systems will be necessary in the near future. Pulsed plasma thrusters (PPTs) were the first form of electric propulsion to be deployed in orbit, and are highly suitable for small satellites due to their inherent simplicity. However, their lifetime is limited by disadvantages such as carbon deposition leading to thruster failure, and complicated feeding systems required due to the conventional use of solid propellants (usually polytetrafluoroethylene (PTFE)). A promising alternative to solid propellants has recently emerged in the form of non-volatile liquids that are stable in vacuum. This study presents a broad comparison of the non-volatile liquid perfluoropolyether (PFPE) and solid PTFE as propellants on a PPT with a common design base. We show that liquid PFPE can be successfully used as a propellant, and exhibits similar plasma discharge properties to conventional solid PTFE, but with a mass bit that is an order of magnitude higher for an identical ablation area. We also demonstrate that the liquid PFPE propellant has exceptional resistance to carbon deposition, completely negating one of the major causes of thruster failure, while solid PTFE exhibited considerable carbon build-up. Energy dispersive X-ray spectroscopy was used to examine the elemental compositions of the surface deposition on the electrodes and the ablation area of the propellant (or PFPE encapsulator). The results show that based on its physical characteristics and behavior, non-volatile liquid PFPE is an extremely promising propellant for use in PPTs, with an extensive scope available for future research and development.

  15. Combustion characteristics of SMX and SMX based propellants

    Science.gov (United States)

    Reese, David A.

    This work investigates the combustion of the new solid nitrate ester 2,3-hydroxymethyl-2,3-dinitro-1,4-butanediol tetranitrate (SMX, C6H 8N6O16). SMX was synthesized for the first time in 2008. It has a melting point of 85 °C and oxygen balance of 0% to CO 2, allowing it to be used as an energetic additive or oxidizer in solid propellants. In addition to its neat combustion characteristics, this work also explores the use of SMX as a potential replacement for nitroglycerin (NG) in double base gun propellants and as a replacement for ammonium perchlorate in composite rocket propellants. The physical properties, sensitivity characteristics, and combustion behaviors of neat SMX were investigated. Its combustion is stable at pressures of up to at least 27.5 MPa (n = 0.81). The observed flame structure is nearly identical to that of other double base propellant ingredients, with a primary flame attached at the surface, a thick isothermal dark zone, and a luminous secondary flame wherein final recombination reactions occur. As a result, the burning rate and primary flame structure can be modeled using existing one-dimensional steady state techniques. A zero gas-phase activation energy approximation results in a good fit between modeled and observed behavior. Additionally, SMX was considered as a replacement for nitroglycerin in a double base propellant. Thermochemical calculations indicate improved performance when compared with the common double base propellant JA2 at SMX loadings above 40 wt-%. Also, since SMX is a room temperature solid, migration may be avoided. Like other nitrate esters, SMX is susceptible to decomposition over long-term storage due to the presence of excess acid in the crystals; the addition of stabilizers (e.g., derivatives of urea) during synthesis should be sufficient to prevent this. the addition of Both unplasticized and plasticized propellants were formulated. Thermal analysis of unplasticized propellant showed a distinct melt

  16. Solid Amalgam Composite Electrode as a New Sensor for the Determination of Biologically Active Compounds

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Navrátil, Tomáš; Lukina, A.; Pecková, K.; Barek, J.

    2007-01-01

    Roč. 52, č. 6 (2007), s. 897-910 ISSN 0009-2223 R&D Projects: GA ČR GA203/07/1195; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z40400503 Keywords : solid composite electrode * solid amalgam electrodes * solid amalgam composite electrode * voltammetry Subject RIV: CG - Electrochemistry Impact factor: 0.529, year: 2007

  17. Composite analysis for solid waste storage area 6

    International Nuclear Information System (INIS)

    Lee, D.W.

    1997-09-01

    The composite analysis (CA) provides an estimate of the potential cumulative impacts to a hypothetical future member of the public from the Solid Waste Storage Area 6 (SWSA 6) disposal operations and all of the other sources of radioactive material in the ground on the ORR that may interact with contamination originating in SWSA 6.The projected annual dose to hypothetical future member of the public from all contributing sources is compared to the primary dose limit of 100 mrem per year and a dose constraint of 30 mrem per year. Consistent with the CA guidance, dose estimates for the first 1000 years after disposal are emphasized for comparison with the primary dose limit and dose constraint.The current land use plan for the ORR is being revised, and may include a reduction in the land currently controlled by DOE on the ORR. The possibility of changes in the land use boundary is considered in the CA as part of the sensitivity and uncertainty analysis of the results, the interpretation of results, and the conclusions

  18. characterization and composition analysis of municipal solid waste

    African Journals Online (AJOL)

    userpc

    ABSTRACT. Municipal Solid Waste (MSW) is produced through human activities and in the last two ... Solid waste samples were collected and analysed from the four major dumpsites in ..... Technology, Ueberlandstrasse 133,. Switzerland.

  19. Composition, production rate and characterization of Greek dental solid waste.

    Science.gov (United States)

    Mandalidis, Alexandros; Topalidis, Antonios; Voudrias, Evangelos A; Iosifidis, Nikolaos

    2018-05-01

    The overall objective of this work is to determine the composition, characterization and production rate of Greek dental solid waste (DSW). This information is important to design and cost management systems for DSW, for safety and health considerations and for assessing environmental impact. A total of 141 kg of DSW produced by a total of 2542 patients in 20 dental practices from Xanthi, Greece was collected, manually separated and weighed over a period of four working weeks. The waste was separated in 19 sub fractions, which were classified in 2 major categories, according to Greek regulations: Domestic-type waste comprising 8% and hazardous waste comprising 92% by weight of total DSW. The latter was further classified in infectious waste, toxic waste and mixed type waste (infectious and toxic together), accounting for 88.5%, 3.5% and 0.03% of total DSW by weight, respectively. The overall unit production rates (mean ± standard error of the mean) were 381 ± 15 g/practice/d and 53.3 ± 1.4 g/patient/d for total DSW, 337 ± 14 g/practice/d and 46.6 ± 1.2 g/patient/d for total infectious DSW, 13.4 ± 0.7 g/practice/d and 2.1 ± 0.1 g/patient/d for total toxic DSW and 30.4 ± 2.5 g/practice/d and 4.6 ± 0.4 g/patient/d for domestic-type waste. Daily DSW production was correlated with daily number of patients and regression correlations were produced. DSW was subject to laboratory characterization in terms of bulk density, calorific value, moisture, ash and volatile solids content. Measured calorific values were compared to predictions from empirical models. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Preparation of nonwoven and green composites from tannery solid wastes

    Science.gov (United States)

    The disposal of solid wastes, such as trimmings and splits generated in various manufacturing processes in a tannery, is a serious challenge to the hides and leather industries. Our effort to address this challenge is to develop new uses and novel biobased products from solid wastes to improve prosp...

  1. THE DETERMINATION OF VOLATILE COMPOSITION OF SOLID FUELS BY CHROMATOGRAPHY

    OpenAIRE

    BICA Marin; SOFRONIE Sorin; CERNAIANU Corina Dana

    2014-01-01

    The volatile materials released during the heating of solid fuels ignite at relatively low temperatures releasing heat function of their quantity and quality. This heat raises the temperature of the solid residue creating the conditions for his ignition and burning. In the case of burning of the pulverized coal the phenomenon of production, ignition and burning of volatile materials are studied in different articles.

  2. Formulation development and characterization of cellulose acetate nitrate based propellants for improved insensitive munitions properties

    Directory of Open Access Journals (Sweden)

    Thelma Manning

    2014-06-01

    Full Text Available Cellulose acetate nitrate (CAN was used as an insensitive energetic binder to improve the insensitive munitions (IM properties of gun propellants to replace the M1 propellant used in 105 mm artillery charges. CAN contains the energetic nitro groups found in nitrocellulose (NC, but also acetyl functionalities, which lowered the polymer's sensitivity to heat and shock, and therefore improved its IM properties relative to NC. The formulation, development and small-scale characterization testing of several CAN-based propellants were done. The formulations, using insensitive energetic solid fillers and high-nitrogen modifiers in place of nitramine were completed. The small scale characterization testing, such as closed bomb testing, small scale sensitivity, thermal stability, and chemical compatibility were done. The mechanical response of the propellants under high-rate uni-axial compression at, hot, cold, and ambient temperatures were also completed. Critical diameter testing, hot fragment conductive ignition (HFCI tests were done to evaluate the propellants' responses to thermal and shock stimuli. Utilizing the propellant chemical composition, theoretical predictions of erosivity were completed. All the small scale test results were utilized to down-select the promising CAN based formulations for large scale demonstration testing such as the ballistic performance and fragment impact testing in the 105 mm M67 artillery charge configurations. The test results completed in the small and large scale testing are discussed.

  3. Assembly of Functional Porous Solids in Complex Hybrid Composites

    National Research Council Canada - National Science Library

    Stein, Andreas

    2004-01-01

    Three-dimensionally ordered macroporous (3DOM) materials with periodic arrays of solid walls possess interesting optical, photonic and reactive properties of interest for camouflage, sensing, sorption, and controlled release...

  4. Perancangan Propeler Self-Propelled Barge

    Directory of Open Access Journals (Sweden)

    Billy Teguh kurniawan

    2013-03-01

    Full Text Available Makalah ini menyampaikan suatu penelitian tentang perancangan propeler yang optimal beserta pemilihan daya mesin yang efisien pada self-propelled barge dengan memperhitungkan besarnya nilai tahanan dari barge tersebut. Dengan penambahan sistem propulsi, diharapkan barge dapat beroperasi dengan lebih efisien dibandingkan saat barge beroperasi menggunakan sistem towing atau ditarik tug boat. Perhitungan tahanan barge dilakukan menggunakan metode Holtrop dan Guldhammer-Harvald sehingga dapat diperhi-tungkan geometri dan jenis propeler yang optimal beserta daya mesin yang efisien untuk barge. Propeler yang dianalisis adalah propeler tipe B-Troost Series, sedangkan variasi yang dilakukan untuk perencanaan propeler pada kajian ini adalah variasi putaran propeler pada rentang antara 310-800 rpm, serta variasi jumlah daun pada rentang tiga, empat, lima, dan enam. Besarnya nilai tahanan self-propelled barge untuk metode Holtrop adalah 105.91 kilonewton, sedangkan hasil per-hitungan dari metode Guldhammer-Harvald didapatkan nilai sebesar 109.14 kilonewton. Tipe propeler yang dipilih setelah dilakukan uji kavitasi adalah tipe Troost Series B4-40, dengan diameter sebesar 2.1 m, efisiensi sebesar 0.421, pitch ratio se-besar 0.591, dengan putaran propeler 400 rpm. Daya mesin yg dibutuhkan barge pada kondisi maksimum (BHPMCR sebesar 1669.5 HP. Dengan mempertimbangkan daya tersebut, maka dipilih mesin jenis Caterpillar tipe Marine 3516B yang mem-punyai daya maksimum sebesar 1285 kilowatt atau 1722.5 horsepower dengan putaran mesin sebesar 1200 rpm

  5. Mars Ascent Vehicle-Propellant Aging

    Science.gov (United States)

    Dankanich, John; Rousseau, Jeremy; Williams, Jacob

    2015-01-01

    This project is to develop and test a new propellant formulation specifically for the Mars Ascent Vehicle (MAV) for the robotic Mars Sample Return mission. The project was initiated under the Planetary Sciences Division In-Space Propulsion Technology (ISPT) program and is continuing under the Mars Exploration Program. The two-stage, solid motor-based MAV has been the leading MAV solution for more than a decade. Additional studies show promise for alternative technologies including hybrid and bipropellant options, but the solid motor design has significant propellant density advantages well suited for physical constraints imposed while using the SkyCrane descent stage. The solid motor concept has lower specific impulse (Isp) than alternatives, but if the first stage and payload remain sufficiently small, the two-stage solid MAV represents a potential low risk approach to meet the mission needs. As the need date for the MAV slips, opportunities exist to advance technology with high on-ramp potential. The baseline propellant for the MAV is currently the carboxyl terminated polybutadiene (CTPB) based formulation TP-H-3062 due to its advantageous low temperature mechanical properties and flight heritage. However, the flight heritage is limited and outside the environments, the MAV must endure. The ISPT program competed a propellant formulation project with industry and selected ATK to develop a new propellant formulation specifically for the MAV application. Working with ATK, a large number of propellant formulations were assessed to either increase performance of a CTPB propellant or improve the low temperature mechanical properties of a hydroxyl terminated polybutadiene (HTPB) propellant. Both propellants demonstrated potential to increase performance over heritage options, but an HTPB propellant formulation, TP-H-3544, was selected for production and testing. The test plan includes propellant aging first at high vacuum conditions, representative of the Mars transit

  6. A research on polyether glycol replaced APCP rocket propellant

    Science.gov (United States)

    Lou, Tianyou; Bao, Chun Jia; Wang, Yiyang

    2017-08-01

    Ammonium perchlorate composite propellant (APCP) is a modern solid rocket propellant used in rocket vehicles. It differs from many traditional solid rocket propellants by the nature of how it is processed. APCP is cast into shape, as opposed to powder pressing it with black powder. This provides manufacturing regularity and repeatability, which are necessary requirements for use in the aerospace industry. For traditional APCP, ingredients normally used are ammonium peroxide, aluminum, Hydroxyl-terminated polybutadiene(HTPB), curing agency and other additives, the greatest disadvantage is that the fuel is too expensive. According to the price we collected in our country, a single kilogram of this fuel will cost 200 Yuan, which is about 35 dollars, for a fan who may use tons of the fuel in a single year, it definitely is a great deal of money. For this reason, we invented a new kind of APCP fuel. Changing adhesive agency from cross-linked htpb to cross linked polyether glycol gives a similar specific thrust, density and mechanical property while costs a lower price.

  7. Municipal solid waste composition determination supporting the integrated solid waste management system in the island of Crete

    International Nuclear Information System (INIS)

    Gidarakos, E.; Havas, G.; Ntzamilis, P.

    2006-01-01

    A one-year survey was conducted in the greater region of Crete (located at the lower region of the Aegean Sea) for the purpose of identifying waste composition (including chemical and physical characterization), as well as any seasonal variation. The investigation was carried out repeatedly at seven landfills and one transfer station in Crete, in four phases. Each sampling phase corresponded to a season (autumn, winter, spring, summer). ASTM D5231-92(2003) standard method and RCRA Waste Sampling Draft Technical Guidance were used. Hand sorting was used for classifying the collected wastes into the following categories: plastics, paper, metals, aluminium, leather-wood-textiles-rubbers, organic wastes, non-combustibles and miscellaneous. Further analysis included proximate and ultimate analysis of combustible materials. Metals such as lead, cadmium and mercury were also investigated. The results show that there has been a significant decrease of organic wastes during the last decade due to the increase of packaging materials, as a result of a change in consumption patterns. Three main waste categories were determined: organic wastes, paper and plastics, which combined represent 76% of the total waste in Crete. Furthermore, a high fraction of glass and a seasonal variation of aluminium indicate a strong correlation of waste composition with certain human activities, such as tourism. There is also a variation between the municipal solid waste (MSW) composition in the region of Crete (2003-2004) and MSW composition suggested in the National Solid Waste Planning (2000) [National Solid Waste Planning, 2000. Completion and particularization of Common Ministerial Act 113944//1944/1997: National Solid Waste Planning, June 2000]. The results of this survey are to be utilized by the regional solid waste authorities in order to establish an integrated waste treatment site, capable of fulfilling the regional waste management demands

  8. Municipal solid waste composition determination supporting the integrated solid waste management system in the island of Crete.

    Science.gov (United States)

    Gidarakos, E; Havas, G; Ntzamilis, P

    2006-01-01

    A one-year survey was conducted in the greater region of Crete (located at the lower region of the Aegean Sea) for the purpose of identifying waste composition (including chemical and physical characterization), as well as any seasonal variation. The investigation was carried out repeatedly at seven landfills and one transfer station in Crete, in four phases. Each sampling phase corresponded to a season (autumn, winter, spring, summer). ASTM D5231-92(2003) standard method and RCRA Waste Sampling Draft Technical Guidance were used. Hand sorting was used for classifying the collected wastes into the following categories: plastics, paper, metals, aluminium, leather-wood-textiles-rubbers, organic wastes, non-combustibles and miscellaneous. Further analysis included proximate and ultimate analysis of combustible materials. Metals such as lead, cadmium and mercury were also investigated. The results show that there has been a significant decrease of organic wastes during the last decade due to the increase of packaging materials, as a result of a change in consumption patterns. Three main waste categories were determined: organic wastes, paper and plastics, which combined represent 76% of the total waste in Crete. Furthermore, a high fraction of glass and a seasonal variation of aluminium indicate a strong correlation of waste composition with certain human activities, such as tourism. There is also a variation between the municipal solid waste (MSW) composition in the region of Crete (2003-2004) and MSW composition suggested in the National Solid Waste Planning (2000) [National Solid Waste Planning, 2000. Completion and particularization of Common Ministerial Act 113944//1944/1997: National Solid Waste Planning, June 2000]. The results of this survey are to be utilized by the regional solid waste authorities in order to establish an integrated waste treatment site, capable of fulfilling the regional waste management demands.

  9. Copper-substituted perovskite compositions for solid oxide fuel cell cathodes and oxygen reduction electrodes in other electrochemical devices

    Science.gov (United States)

    Rieke, Peter C [Pasco, WA; Coffey, Gregory W [Richland, WA; Pederson, Larry R [Kennewick, WA; Marina, Olga A [Richland, WA; Hardy, John S [Richland, WA; Singh, Prabhaker [Richland, WA; Thomsen, Edwin C [Richland, WA

    2010-07-20

    The present invention provides novel compositions that find advantageous use in making electrodes for electrochemical cells. Also provided are electrochemical devices that include active oxygen reduction electrodes, such as solid oxide fuel cells, sensors, pumps and the like. The compositions comprises a copper-substituted ferrite perovskite material. The invention also provides novel methods for making and using the electrode compositions and solid oxide fuel cells and solid oxide fuel cell assemblies having cathodes comprising the compositions.

  10. Abundance, composition and distribution of solid wastes in the ...

    African Journals Online (AJOL)

    ... 2013 at 68 stations in six depth strata using the bottom trawl swept area method. ... (42%), longlines and hooks (7%), plastic bags (4%), floats (2%), and clothing (1%). ... solid waste pollution is not at present a major problem in Lake Victoria.

  11. Tip-modified Propellers

    DEFF Research Database (Denmark)

    Andersen, Poul

    1999-01-01

    The paper deals with tip-modified propellers and the methods which, over a period of two decades, have been applied to develop such propellers. The development is driven by the urge to increase the efficiency of propellers and can be seen as analogous to fitting end plates and winglets to aircraft...... propeller, have efficiency increases of a reasonable magnitude in both open-water and behind-ship conditions....

  12. Nutritional composition of bioproducts generated from semi-solid ...

    African Journals Online (AJOL)

    sunny t

    2016-03-23

    Mar 23, 2016 ... composition, content of macro and micro minerals, amino acid and proteolytic activity were assessed in the pineapple ..... Minerals are indispensable in human metabolism, part of important reactions, transmission of nerve impulses, bone development and regulation of salt and water balance. (Okoro and ...

  13. The conductivity and stability of polymer composite solid electrolyte upon addition of graphene

    Science.gov (United States)

    Hamid, Farzana Abd.; Salleh, Fauzani Md.; Mohamed, Nor Sabirin

    2017-12-01

    The effect of graphene composition on the conductivity and stability of polymer composite solid electrolyte was studied. These polymer composite solid electrolytes were synthesized by sol gel method and prepared via the solution-casting technique. The compositions of graphene were varied between 10 wt% to 70 wt%. The changes in the functional group of polymer composite after the addition of graphene were characterized by Fourier Transform InfraRed spectroscopy. Electrochemical impedance spectroscopy was conducted at ambient temperature in the frequency range of 10 Hz to 1 MHz to study the conductivity of the polymer composite. The highest conductivity was obtained at 60 wt% graphene with the value of 2.85×10-4 Scm-1. Sample without the addition of graphene showed the lowest conductivity value of 1.77×10-7 Scm-1 and acts as an insulator. The high conductivity at 60 wt% graphene loading is related to dehydration of cellulose. This is supported by the FTIR spectrum where the absorption peaks of C-O stretching vibrations of polymer composite is weakened and the hydroxyl group is slightly shifted compared to the FTIR spectrum without the addition of graphene. Linear sweep voltammetry results demonstrated that the polymer composite solid electrolyte exhibited electrochemical stability up to 3.2 V.

  14. Sulfur tolerant composite cermet electrodes for solid oxide electrochemical cells

    Science.gov (United States)

    Isenberg, Arnold O.

    1987-01-01

    An electrochemical apparatus is made containing an exterior electrode bonded to the exterior of a tubular, solid, oxygen ion conducting electrolyte where the electrolyte is also in contact with an interior electrode, said exterior electrode comprising particles of an electronic conductor contacting the electrolyte, where a ceramic metal oxide coating partially surrounds the particles and is bonded to the electrolyte, and where a coating of an ionic-electronic conductive material is attached to the ceramic metal oxide coating and to the exposed portions of the particles.

  15. Synthesisofc-lifepo4 composite by solid state reaction method

    Science.gov (United States)

    Rahayu, I.; Hidayat, S.; Noviyanti, A. R.; Rakhmawaty, D.; Ernawati, E.

    2017-02-01

    In this research, the enhancement of LiFePO4 conductivity was conducted by doping method with carbon materials. Carbon-based materials were obtained from the mixture of sucrose, and the precursor of LiH2PO4 and α-Fe2O3 was synthesized by solid state reaction. Sintering temperature was varied at 700°C, 800°C, 900°C and 1,000°C. The result showed that C-LiFePO4 could be synthesized by using solid state reaction method. Based on the XRD and FTIR spectrums, C-LiFePO4 can be identified as the type of crystal, characterized by the appearance of sharp signal on (011), (211) and typical peak of LiFePO4 materials. The result of conductivity measurement from C-LiFePO4 at sintering temperature of 900°C and 1,000°C was 2×10-4 S/cm and 4×10-4S/cm, respectively. The conductivity value at sintering temperature of 700°C and 800°C was very small (<10-6 S/cm), which cannot be measured by the existing equipment.

  16. Process for making solid-state radiation-emitting composition

    Science.gov (United States)

    Ashley, C.S.; Brinker, C.J.; Reed, S.; Walko, R.J.

    1993-08-31

    The invention provides a process for loading an aerogel substrate with tritium and the resultant compositions. According to the process, an aerogel substrate is hydrolyzed so that surface OH groups are formed. The hydrolyzed aerogel is then subjected to tritium exchange employing, for example, a tritium-containing gas, whereby tritium atoms replace H atoms of surface OH groups. OH and/or CH groups of residual alcohol present in the aerogel may also undergo tritium exchange.

  17. Role of particle size and composition in metal adsorption by solids deposited on urban road surfaces

    International Nuclear Information System (INIS)

    Gunawardana, Chandima; Egodawatta, Prasanna; Goonetilleke, Ashantha

    2014-01-01

    Despite common knowledge that the metal content adsorbed by fine particles is relatively higher compared to coarser particles, the reasons for this phenomenon have gained little research attention. The research study discussed in the paper investigated the variations in metal content for different particle sizes of solids associated with pollutant build-up on urban road surfaces. Data analysis confirmed that parameters favourable for metal adsorption to solids such as specific surface area, organic carbon content, effective cation exchange capacity and clay forming minerals content decrease with the increase in particle size. Furthermore, the mineralogical composition of solids was found to be the governing factor influencing the specific surface area and effective cation exchange capacity. There is high quartz content in particles >150 μm compared to particles <150 μm. As particle size reduces below 150 μm, the clay forming minerals content increases, providing favourable physical and chemical properties that influence adsorption. -- Highlights: • Physico-chemical parameters investigated in build-up samples from 32 road surfaces. • Mineralogical composition primarily governs the physico-chemical characteristics. • High clay forming mineral content in fine solids increases SSA and ECEC. • Characteristics influenced by quartz and amorphous content with particle size. • High quartz content in coarse particles contributes reduced metal adsorption. -- The mineralogical composition of solids is the governing factor influencing metal adsorption to solids in pollutant build-up on urban surfaces

  18. Influence of different propellant systems on ablation of EPDM insulators in overload state

    Science.gov (United States)

    Guan, Yiwen; Li, Jiang; Liu, Yang; Xu, Tuanwei

    2018-04-01

    This study examines the propellants used in full-scale solid rocket motors (SRM) and investigates how insulator ablation is affected by two propellant formulations (A and B) during flight overload conditions. An experimental study, theoretical analysis, and numerical simulations were performed to discover the intrinsic causes of insulator ablation rates from the perspective of lab-scaled ground-firing tests, the decoupling of thermochemical ablation, and particle erosion. In addition, the difference in propellant composition, and the insulator charring layer microstructure were analyzed. Results reveal that the degree of insulator ablation is positively correlated with the propellant burn rate, particle velocity, and aggregate concentrations during the condensed phase. A lower ratio of energetic additive material in the AP oxidizer of the propellant is promising for the reduction in particle size and increase in the burn rate and pressure index. However, the overall higher velocity of a two-phase flow causes severe erosion of the insulation material. While the higher ratio of energetic additive to the AP oxidizer imparts a smaller ablation rate to the insulator (under lab-scale test conditions), the slag deposition problem in the combustion chamber may cause catastrophic consequences for future large full-scale SRM flight experiments.

  19. Solid Particle Erosion Behaviors of Carbon-Fiber Epoxy Composite and Pure Titanium

    Science.gov (United States)

    Cai, Feng; Gao, Feng; Pant, Shashank; Huang, Xiao; Yang, Qi

    2016-01-01

    Rotor blades of Bell CH-146 Griffon helicopter experience excessive solid particle erosion at low altitudes in desert environment. The rotor blade is made of an advanced light-weight composite which, however, has a low resistance to solid particle erosion. Coatings have been developed and applied to protect the composite blade. However, due to the influence of coating process on composite material, the compatibility between coating and composite base, and the challenges of repairing damaged coatings as well as the inconsistency between the old and new coatings, replaceable thin metal shielding is an alternative approach; and titanium, due to its high-specific strength and better formability, is an ideal candidate. This work investigates solid particle erosion behaviors of carbon-fiber epoxy composite and titanium in order to assess the feasibility of titanium as a viable candidate for erosion shielding. Experiment results showed that carbon-fiber epoxy composite showed a brittle erosion behavior, whereas titanium showed a ductile erosion mode. The erosion rate on composite was 1.5 times of that on titanium at impingement angle 15° and increased to 5 times at impact angle 90°.

  20. Polyacrylate microspheres composite for all-solid-state reference electrodes.

    Science.gov (United States)

    Kisiel, Anna; Donten, Mikołaj; Mieczkowski, Józef; Rius-Ruiz, F Xavier; Maksymiuk, Krzysztof; Michalska, Agata

    2010-09-01

    A novel concept is proposed for the encapsulation of components within polyacrylate microspheres, prior to their incorporation into a membrane phase. Thus finer and better controlled dispersion of heterogeneous membrane components can be achieved. This concept was verified by using a poly(n-butyl acrylate) membrane-based reference electrode as an example. In this example the proper dispersion of solid constituents of the heterogeneous membrane and prevention of their leakage are both of primary importance. Potassium chloride-loaded poly(n-butyl acrylate) microspheres were prepared and then left in contact with silver nitrate to convert some of the KCl into AgCl. The material obtained was introduced into a poly(n-butyl acrylate) membrane. The reference electrode membranes obtained in this way were characterized with much more stable potential (both in different electrolytes and over time) compared with electrodes prepared by the direct introduction of KCl and AgCl to the membrane.

  1. Numerical Analysis of Ice Impacts on Azimuth Propeller

    Science.gov (United States)

    2013-09-01

    uniformity as one solid object, though the built-on process is recognized as well. The number of blades for this propeller varies to control cavitation ...Figure 7). The CRP allows the hydrodynamic advantage of regaining lost rotational energy from the first propeller, which is the conventional...it speeds flow through and accelerates it past the propellers. Decelerating duct slows the flow and allows for greatly reduced cavitation and

  2. Aircraft Propeller Hub Repair

    Energy Technology Data Exchange (ETDEWEB)

    Muth, Thomas R [ORNL; Peter, William H [ORNL

    2015-02-13

    The team performed a literature review, conducted residual stress measurements, performed failure analysis, and demonstrated a solid state additive manufacturing repair technique on samples removed from a scrapped propeller hub. The team evaluated multiple options for hub repair that included existing metal buildup technologies that the Federal Aviation Administration (FAA) has already embraced, such as cold spray, high velocity oxy-fuel deposition (HVOF), and plasma spray. In addition the team helped Piedmont Propulsion Systems, LLC (PPS) evaluate three potential solutions that could be deployed at different stages in the life cycle of aluminum alloy hubs, in addition to the conventional spray coating method for repair. For new hubs, a machining practice to prevent fretting with the steel drive shaft was recommended. For hubs that were refurbished with some material remaining above the minimal material condition (MMC), a silver interface applied by an electromagnetic pulse additive manufacturing method was recommended. For hubs that were at or below the MMC, a solid state additive manufacturing technique using ultrasonic welding (UW) of thin layers of 7075 aluminum to the hub interface was recommended. A cladding demonstration using the UW technique achieved mechanical bonding of the layers showing promise as a viable repair method.

  3. Composite beryllium-ceramics breeder pin elements for a gas cooled solid blanket

    International Nuclear Information System (INIS)

    Carre, F.; Chevreau, G.; Gervaise, F.; Proust, E.

    1986-06-01

    Helium coolant have main advantages compared to water for solid blankets. But limitations exist too and the development of attractive helium cooled blankets based on breeder pin assemblies has been essentially made possible by the derivation from recent CEA neutronic studies of an optimized composite beryllium/ceramics breeder arrangement. Description of the proposed toroidal blanket layout for Net is made together with the analysis of its main performance. Merits of the considered composite Be/ceramics breeder elements are discussed

  4. TRIDYN - binary collision simulation of atomic collisions dynamic composition changes in solids

    International Nuclear Information System (INIS)

    Moeller, W.; Eckstein, W.

    1988-05-01

    The report deals with the computerized simulation of the following problem: a beam of fast ions entering a solid substance is slowed down and scattered due to electronic interaction and nuclear collisions. Together with created recoil atoms local compositional changes are produced. For large fluences collisional mixing is caused in layered substances. (BHO)

  5. COMMUNITY SCALE STREAM TAXA SENSITIVITIES TO DIFFERENT COMPOSITIONS OF EXCESS TOTAL DISSOLVED SOLIDS

    Science.gov (United States)

    Model stream chronic dosing studies (42 d) were conducted with three total dissolved solids (TDS) recipes. The recipes differed in composition of major ions. Community scale emergence was compared with single-species responses conducted simultaneously using the whole effluent tox...

  6. Semi-solid high pressure die casting of metal matrix composites produced by liquid state processing

    CSIR Research Space (South Africa)

    Ivanchev, L

    2012-10-01

    Full Text Available stirring. The composite was then transferred to a High Pressure Die Casting (HPDC) machine in the semi-solid state. The micron size particles were found to be predominantly in the intergranular eutectic while the nano-particles were predominantly...

  7. Chemical composition shape form and size of suspended solids in the atmosphere carried by rain water

    International Nuclear Information System (INIS)

    Iturbe G, J.L.; Lopez M, B.E.; Torre O, J. De la

    2001-01-01

    The interest of this work is to know about shape form, size and chemical composition of the suspended solids in the atmosphere of Toluca city and which are carried by the rains. The harvest of the samples was carried out during january to november 1999. The separation of the particulate matter from the rain water was realized through centrifugation. The solids were analysed by Scanning Electron Microscopy to know the shape form and size and the chemical composition was determined by X-ray dispersive energy in general form and of some particles individually analysed. The p H was measured to the solutions and the quantification of some dissolved ions by the Icp technique was realized. The results of the solids showed C, O, Na, Mg, Al, Si, S, P, K, Ca, Ti and Fe. Moreover they present sizes which varying from a ten of nanometers until some tens of microns. (Author)

  8. Solid state reaction in alumina nanoparticles/LZSA glass-ceramic composites

    International Nuclear Information System (INIS)

    Montedo, O.K.; Oliveira, A.N. de; Raupp-Pereira, F.

    2016-01-01

    Full text: The aim of this work is to present results related to solid state reactions on LZSA glass-ceramic composites containing alumina reinforcement nano-particles. A LZSA (Li2O-ZrO2-SiO2-Al2O3) glass-ceramic has been prepared by sintering of powders and characterized. Composites containing 0 to 77 vol.% of alumina nanoparticles (27-43 nm APS, 35 m2.g-1 SSA) and a 16.9Li2O•5.0ZrO2•65.1SiO2•8.6Al2O3 glass-ceramic matrix have been prepared. X-ray diffractometry studies have been performed in order of investigating the solid state reactions occurring in LZSA-based composites. Results of the XRD patterns have been related to the coefficient of thermal expansion (CTE), Young modulus, and dielectric constant, showing that, in comparison with the glass-ceramic composition, the composites showed a decrease of CTE with the alumina concentration increasing, due to the increasing of beta-spodumeness formation (solid solution of beta-spodumene, Li2O.Al2O3.4-10SiO2). The performance of the glass-ceramic was improved with the alumina nano-particles addition, showing potential of using in the preparation of Low Thermal Co-fired Ceramics (LTCC). (author)

  9. Composite Coatings with Ceramic Matrix Including Nanomaterials as Solid Lubricants for Oil-Less Automotive Applications

    Directory of Open Access Journals (Sweden)

    Posmyk A.

    2016-06-01

    Full Text Available The paper presents the theoretical basis of manufacturing and chosen applications of composite coatings with ceramic matrix containing nanomaterials as a solid lubricant (AHC+NL. From a theoretical point of view, in order to reduce the friction coefficient of sliding contacts, two materials are required, i.e. one with a high hardness and the other with low shear strength. In case of composite coatings AHC+NL the matrix is a very hard and wear resistant anodic oxide coating (AHC whereas the solid lubricant used is the nanomaterial (NL featuring a low shear strength such as glassy carbon nanotubes (GC. Friction coefficient of cast iron GJL-350 sliding against the coating itself is much higher (0.18-0.22 than when it slides against a composite coating (0.08-0.14. It is possible to reduce the friction due to the presence of carbon nanotubes, or metal nanowires.

  10. Multigrid Finite Element Method in Calculation of 3D Homogeneous and Composite Solids

    Directory of Open Access Journals (Sweden)

    A.D. Matveev

    2016-12-01

    Full Text Available In the present paper, a method of multigrid finite elements to calculate elastic three-dimensional homogeneous and composite solids under static loading has been suggested. The method has been developed based on the finite element method algorithms using homogeneous and composite three-dimensional multigrid finite elements (MFE. The procedures for construction of MFE of both rectangular parallelepiped and complex shapes have been shown. The advantages of MFE are that they take into account, following the rules of the microapproach, heterogeneous and microhomogeneous structures of the bodies, describe the three-dimensional stress-strain state (without any simplifying hypotheses in homogeneous and composite solids, as well as generate small dimensional discrete models and numerical solutions with a high accuracy.

  11. Propellant Preparation Laboratory Complex (Area1-21)

    Data.gov (United States)

    Federal Laboratory Consortium — Description: Area 1-21 is an explosion resistant complex of nine cells built into the side of a granite ridge. Three solid propellant cutting cells are housed in the...

  12. Municipal Solid Waste Composition Study of Selected Area in Gambang, Pahang

    Science.gov (United States)

    Mokhtar, Nadiah; Ishak, Wan Faizal Wan; Suraya Romali, Noor; Fatimah Che Osmi, Siti; Armi Abu Samah, Mohd

    2013-06-01

    The amount of municipal solid waste (MSW) generated continue to increase in response to rapid growth in population, change in life style and accelerated urbanization and industrialization process. The study on MSW is important in order to determine the composition further seeks an immediate remedy to minimize the waste generated at the early stage. As most of the MSW goes to the landfill or dumping sites, particularly in Malaysia, closure of filled-up landfill may become an alarm clock for an immediate action of proper solid waste management. This research aims to determine the waste composition generated from selected residential area at Gambang, Kuantan, Pahang which represent Old residential area (ORA), Intermediate residential area (IRA) and New residential area (NRA). The study was conducted by segregating and weighing solid waste in the residential area into 6 main components ie., food waste, paper, plastic, glass, metal and others. In a period of four weeks, samples from the residential unit were taken and analyzed. The MSW generation rates were recorded vary from 0.217 to 0.388 kg person-1day-1. Food waste has become the major solid waste component generated daily which mounted up to 50%. From this research, the result revealed that the recyclable composition of waste generated by residents have a potential to be reuse, recycle and reduce at the point sources.

  13. Municipal Solid Waste Composition Study of Selected Area in Gambang, Pahang

    International Nuclear Information System (INIS)

    Mokhtar, Nadiah; Romali, Noor Suraya; Osmi, Siti Fatimah Che; Ishak, Wan Faizal Wan; Samah, Mohd Armi Abu

    2013-01-01

    The amount of municipal solid waste (MSW) generated continue to increase in response to rapid growth in population, change in life style and accelerated urbanization and industrialization process. The study on MSW is important in order to determine the composition further seeks an immediate remedy to minimize the waste generated at the early stage. As most of the MSW goes to the landfill or dumping sites, particularly in Malaysia, closure of filled-up landfill may become an alarm clock for an immediate action of proper solid waste management. This research aims to determine the waste composition generated from selected residential area at Gambang, Kuantan, Pahang which represent Old residential area (ORA), Intermediate residential area (IRA) and New residential area (NRA). The study was conducted by segregating and weighing solid waste in the residential area into 6 main components ie., food waste, paper, plastic, glass, metal and others. In a period of four weeks, samples from the residential unit were taken and analyzed. The MSW generation rates were recorded vary from 0.217 to 0.388 kg person −1 day −1 . Food waste has become the major solid waste component generated daily which mounted up to 50%. From this research, the result revealed that the recyclable composition of waste generated by residents have a potential to be reuse, recycle and reduce at the point sources.

  14. Influence of process parameters to composite interface organization and performance of liquid/solid bimetal

    International Nuclear Information System (INIS)

    Rong, S F; Zhu, Y C; Wu, Y H; Yang, P H; Duan, X L; Zhou, H T

    2015-01-01

    The liquid-solid composite technique was used to prepare the high carbon high chromium steel (HCHCS) and low alloy steel (LCS) bimetal composite materials by means of insert casting method. The influence of some process parameters such as liquid-solid ratio, preheat temperature, pouring temperature on the interface microstructure and mechanical properties were studied. Interface microstructure and element distribution were analyzed. The results show that the interface microstructure becomes better, and bonding area becomes thicker with the increase of the volume of liquid to solid ratio, preheating temperature and pouring temperature. When the liquid-solid ratio is 8:1, the preheating temperature is 300 °C and the pouring temperature is 1565 °C, a good metallurgical bonding area without any hole can be obtained with the interface combination of diffusion and fusion. The composite interface structure was composed of a core material diffusion layer, a cooling solidification layer, a direction growth layer and some cell particles. The elements of C, Cr and Mn diffuse from the HCHCS side to the alloy steel side. The microhardness increased in the gradient from the LCS side to the HCHCS. The microhardness of the interface is significantly higher than that of LCS. (paper)

  15. Lanthanum gallate and ceria composite as electrolyte for solid oxide fuel cells

    International Nuclear Information System (INIS)

    Li Shuai; Li Zhicheng; Bergman, Bill

    2010-01-01

    The composite of doped lanthanum gallate (La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 2.85 , LSGM) and doped ceria (Ce 0.8 Sm 0.2 O 1.9 , CSO) was investigated as an electrolyte for solid oxide fuel cell (SOFC). The LSGM-CSO composite was examined by X-ray diffraction (XRD) and impedance spectroscopy. It was found that the sintered LSGM-CSO composite contains mainly fluorite CeO 2 phase and a minority impurity phase, Sm 3 Ga 5 O 12 . The LSGM-CSO composite electrolyte shows a small grain boundary response in the impedance spectroscopy as compared to LSGM and CSO pellets. The composite electrolyte exhibits the highest conductivity in the temperature range of 250-600 o C, compared to LSGM and CSO. The LSGM-CSO composite can be expected to be an attractive intermediate temperature electrolyte material for solid oxide fuel cells.

  16. Lanthanum gallate and ceria composite as electrolyte for solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Li Shuai, E-mail: shuail@kth.s [Department of Materials Science and Engineering, School of Industrial Engineering and Management, Royal Institute of Technology, SE 10044 Stockholm (Sweden); Li Zhicheng [School of Materials Science and Engineering, Central South University, 410083 Changsha, Hunan (China); Bergman, Bill [Department of Materials Science and Engineering, School of Industrial Engineering and Management, Royal Institute of Technology, SE 10044 Stockholm (Sweden)

    2010-03-04

    The composite of doped lanthanum gallate (La{sub 0.9}Sr{sub 0.1}Ga{sub 0.8}Mg{sub 0.2}O{sub 2.85}, LSGM) and doped ceria (Ce{sub 0.8}Sm{sub 0.2}O{sub 1.9}, CSO) was investigated as an electrolyte for solid oxide fuel cell (SOFC). The LSGM-CSO composite was examined by X-ray diffraction (XRD) and impedance spectroscopy. It was found that the sintered LSGM-CSO composite contains mainly fluorite CeO{sub 2} phase and a minority impurity phase, Sm{sub 3}Ga{sub 5}O{sub 12}. The LSGM-CSO composite electrolyte shows a small grain boundary response in the impedance spectroscopy as compared to LSGM and CSO pellets. The composite electrolyte exhibits the highest conductivity in the temperature range of 250-600 {sup o}C, compared to LSGM and CSO. The LSGM-CSO composite can be expected to be an attractive intermediate temperature electrolyte material for solid oxide fuel cells.

  17. Solid Particle Erosion of Date Palm Leaf Fiber Reinforced Polyvinyl Alcohol Composites

    Directory of Open Access Journals (Sweden)

    Jyoti R. Mohanty

    2014-01-01

    Full Text Available Solid particle erosion behavior of short date palm leaf (DPL fiber reinforced polyvinyl alcohol (PVA composite has been studied using silica sand particles (200 ± 50 μm as an erodent at different impingement angles (15–90° and impact velocities (48–109 m/s. The influence of fiber content (wt% of DPL fiber on erosion rate of PVA/DPL composite has also been investigated. The neat PVA shows maximum erosion rate at 30° impingement angle whereas PVA/DPL composites exhibit maximum erosion rate at 45° impingement angle irrespective of fiber loading showing semiductile behavior. The erosion efficiency of PVA and its composites varies from 0.735 to 16.289% for different impact velocities studied. The eroded surfaces were observed under scanning electron microscope (SEM to understand the erosion mechanism.

  18. Evaluation and modeling of the eutectic composition of various drug-polyethylene glycol solid dispersions.

    Science.gov (United States)

    Baird, Jared A; Taylor, Lynne S

    2011-06-01

    The purpose of this study was to gain a better understanding of which factors contribute to the eutectic composition of drug-polyethylene glycol (PEG) blends and to compare experimental values with predictions from the semi-empirical model developed by Lacoulonche et al. Eutectic compositions of various drug-PEG 3350 solid dispersions were predicted, assuming athermal mixing, and compared to experimentally determined eutectic points. The presence or absence of specific interactions between the drug and PEG 3350 were investigated using Fourier transform infrared (FT-IR) spectroscopy. The eutectic composition for haloperidol-PEG and loratadine-PEG solid dispersions was accurately predicted using the model, while predictions for aceclofenac-PEG and chlorpropamide-PEG were very different from those experimentally observed. Deviations in the model prediction from ideal behavior for the systems evaluated were confirmed to be due to the presence of specific interactions between the drug and polymer, as demonstrated by IR spectroscopy. Detailed analysis showed that the eutectic composition prediction from the model is interdependent on the crystal lattice energy of the drug compound (evaluated from the melting temperature and the heat of fusion) as well as the nature of the drug-polymer interactions. In conclusion, for compounds with melting points less than 200°C, the model is ideally suited for predicting the eutectic composition of systems where there is an absence of drug-polymer interactions.

  19. Inter-Batch Variation and the Effect of Casting Vacuum on Ballistic and Mechanical Properties of a High Performing Cast Composite Rocket Propellant

    Science.gov (United States)

    2014-12-01

    X 5 mm with a bandsaw. Longitudinal faces were coated (inhibited) with an epoxy resin and burned in a Crawford-type low pressure strand burner. The...batch (P0190) is the highest. For strain at maximum stress and strain at break the trend is reversed with the highest values for P0188 and lowest...Appendix A: Propellant Strand Burn Results Table A1: Low pressure strand burn results for P0188, full vacuum coated with epoxy R180/H180

  20. Revisiting the elemental composition and the calorific value of the organic fraction of municipal solid wastes.

    Science.gov (United States)

    Komilis, Dimitrios; Evangelou, Alexandros; Giannakis, Georgios; Lymperis, Constantinos

    2012-03-01

    In this work, the elemental content (C, N, H, S, O), the organic matter content and the calorific value of various organic components that are commonly found in the municipal solid waste stream were measured. The objective of this work was to develop an empirical equation to describe the calorific value of the organic fraction of municipal solid waste as a function of its elemental composition. The MSW components were grouped into paper wastes, food wastes, yard wastes and plastics. Sample sizes ranged from 0.2 to 0.5 kg. In addition to the above individual components, commingled municipal solid wastes were sampled from a bio-drying facility located in Crete (sample sizes ranged from 8 to 15 kg) and were analyzed for the same parameters. Based on the results of this work, an improved empirical model was developed that revealed that carbon, hydrogen and oxygen were the only statistically significant predictors of calorific value. Total organic carbon was statistically similar to total carbon for most materials in this work. The carbon to organic matter ratio of 26 municipal solid waste substrates and of 18 organic composts varied from 0.40 to 0.99. An approximate chemical empirical formula calculated for the organic fraction of commingled municipal solid wastes was C(32)NH(55)O(16). Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Hydrodynamics of Ship Propellers

    DEFF Research Database (Denmark)

    Breslin, John P.; Andersen, Poul

    This book deals with flows over propellers operating behind ships, and the hydrodynamic forces and moments which the propeller generates on the shaft and on the ship hull.The first part of the text is devoted to fundamentals of the flow about hydrofoil sections (with and without cavitation...... of an intermittently cavitating propeller in a wake and the pressures and forces it exerts on the shaft and on the ship hull is examined. A final chapter discusses the optimization of efficiency of compound propulsors. The authors have taken care to clearly describe physical concepts and mathematical steps. Appendices...

  2. All-solid state flexible supercapacitors based on graphene/polymer composites

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Won; Choi, Bong Gill, E-mail: bgchoi@kangwon.ac.kr

    2015-06-01

    Recent advances in lightweight, flexible, and wearable electronic equipment has led to advancements in the development of sufficiently compact and flexible energy storage. A challenge remains to integrate the storage elements as closely as possible within a fully flexible device. Here, we demonstrate the fabrication of all-solid state flexible supercapacitors with the integration of two electrodes that consist of graphene/polymer composites. Robust conductive free-standing thin graphene/polymer composite electrodes were prepared through a simple “physical grinding” process. As-prepared composite electrodes store energy up to a reversible gravimetric capacitance of 90.6 F/g, at a constant current density of 0.5 A/g while also delivering long-term durability (90% retention) for excess of five-thousands of cycles. Notably, the enhancement of mechanical properties of supercapacitors enables them to maintain their electrochemical performance even when twisted or folded. This straightforward approach to the fabrication of fully flexible supercapacitors provides new design opportunities within wearable electronics and electrochemical applications. - Highlights: • All solid-sate supercapacitors were fabricated using graphene/polymer composite electrodes. • Supercapacitor devices show an excellent mechanical flexibility. • High electrochemical performances were demonstrated.

  3. Electrophoretic deposition of 9-YSZ solid electrolyte on Ni- YSZ composite

    International Nuclear Information System (INIS)

    Santos, F.S.; Yoshito, W.K.; Lazar, D.R.R.; Ussui, V.

    2010-01-01

    9-YSZ ceramic and Ni-YSZ metal/ceramic composite are the more commonly used materials for the fabrication of solid oxide fuel cell electrolyte and anode, respectively. The main challenges for these applications are the forming of both materials as superposed double thin layers. In the present work ceramic powder of 9- YSZ was synthesized by a coprecipitation technique and the Ni O-YSZ composite by a combustion technique. The later was formed by uniaxial pressing as cylindrical pellets of 15 mm diameter. Thin ceramic layers of 9-YSZ were deposited on composite pellets from a suspension with 10% solid content by an Electrophoretic Deposition technique. Applied voltage varied in the range of 30 to 200 V and deposition time from 15 to 90 seconds, evaluating the deposited mass, porosity on the interface and adhesion of layers. Resulted ceramics were characterized by X-ray diffraction and were observed in a scanning electron microscope. Results showed that deposited layers are thin (∼20μm), dense and have good adhesion on the surface of composite substrate. (author)

  4. All-solid state flexible supercapacitors based on graphene/polymer composites

    International Nuclear Information System (INIS)

    Kim, Jung Won; Choi, Bong Gill

    2015-01-01

    Recent advances in lightweight, flexible, and wearable electronic equipment has led to advancements in the development of sufficiently compact and flexible energy storage. A challenge remains to integrate the storage elements as closely as possible within a fully flexible device. Here, we demonstrate the fabrication of all-solid state flexible supercapacitors with the integration of two electrodes that consist of graphene/polymer composites. Robust conductive free-standing thin graphene/polymer composite electrodes were prepared through a simple “physical grinding” process. As-prepared composite electrodes store energy up to a reversible gravimetric capacitance of 90.6 F/g, at a constant current density of 0.5 A/g while also delivering long-term durability (90% retention) for excess of five-thousands of cycles. Notably, the enhancement of mechanical properties of supercapacitors enables them to maintain their electrochemical performance even when twisted or folded. This straightforward approach to the fabrication of fully flexible supercapacitors provides new design opportunities within wearable electronics and electrochemical applications. - Highlights: • All solid-sate supercapacitors were fabricated using graphene/polymer composite electrodes. • Supercapacitor devices show an excellent mechanical flexibility. • High electrochemical performances were demonstrated

  5. Composite cathode based on yttria stabilized bismuth oxide for low-temperature solid oxide fuel cells

    International Nuclear Information System (INIS)

    Xia Changrong; Zhang Yuelan; Liu Meilin

    2003-01-01

    Composites consisting of silver and yttria stabilized bismuth oxide (YSB) have been investigated as cathodes for low-temperature honeycomb solid oxide fuel cells with stabilized zirconia as electrolytes. At 600 deg. C, the interfacial polarization resistances of a porous YSB-Ag cathode is about 0.3 Ω cm 2 , more than one order of magnitude smaller than those of other reported cathodes on stabilized zirconia. For example, the interfacial resistances of a traditional YSZ-lanthanum maganites composite cathode is about 11.4 Ω cm 2 at 600 deg. C. Impedance analysis indicated that the performance of an YSB-Ag composite cathode fired at 850 deg. C for 2 h is severely limited by gas transport due to insufficient porosity. The high performance of the YSB-Ag cathodes is very encouraging for developing honeycomb fuel cells to be operated at temperatures below 600 deg. C

  6. A new percolation model for composite solid electrolytes and dispersed ionic conductors

    Science.gov (United States)

    Risyad Hasyim, Muhammad; Lanagan, Michael T.

    2018-02-01

    Composite solid electrolytes (CSEs) including conductor/insulator composites known as dispersed ionic conductors (DICs) have motivated the development of novel percolation models that describe their conductivity. Despite the long history, existing models lack in one or more key areas: (1) rigorous foundation for their physical theory, (2) explanation for non-universal conductor-insulator transition, (3) classification of DICs, and (4) extension to frequency-domain. This work describes a frequency-domain effective medium approximation (EMA) of a bond percolation model for CSEs. The EMA is derived entirely from Maxwell’s equations and contains basic microstructure parameters. The model was applied successfully to several composite systems from literature. Simulations and fitting of literature data address these key areas and illustrate the interplay between space charge layer properties and bulk microstructure.

  7. Indirect Determination of Chemical Composition and Fuel Characteristics of Solid Waste

    DEFF Research Database (Denmark)

    Riber, Christian; Christensen, Thomas Højlund

    Determination of chemical composition of solid waste can be performed directly or indirectly by analysis of combustion products. The indirect methodology instrumented by a full scale incinerator is the only method that can conclude on elements in trace concentrations. These elements are of great...... interest in evaluating waste management options by for example LCA modeling. A methodology description of indirect determination of chemical composition and fuel properties of waste is provided and validated by examples. Indirect analysis of different waste types shows that the chemical composition...... is significantly dependent on waste type. And the analysis concludes that the transfer of substances in the incinerator is a function of waste chemical content, incinerator technology and waste physical properties. The importance of correct representation of rare items in the waste with high concentrations...

  8. Municipal solid waste composition: Sampling methodology, statistical analyses, and case study evaluation

    International Nuclear Information System (INIS)

    Edjabou, Maklawe Essonanawe; Jensen, Morten Bang; Götze, Ramona; Pivnenko, Kostyantyn; Petersen, Claus; Scheutz, Charlotte; Astrup, Thomas Fruergaard

    2015-01-01

    Highlights: • Tiered approach to waste sorting ensures flexibility and facilitates comparison of solid waste composition data. • Food and miscellaneous wastes are the main fractions contributing to the residual household waste. • Separation of food packaging from food leftovers during sorting is not critical for determination of the solid waste composition. - Abstract: Sound waste management and optimisation of resource recovery require reliable data on solid waste generation and composition. In the absence of standardised and commonly accepted waste characterisation methodologies, various approaches have been reported in literature. This limits both comparability and applicability of the results. In this study, a waste sampling and sorting methodology for efficient and statistically robust characterisation of solid waste was introduced. The methodology was applied to residual waste collected from 1442 households distributed among 10 individual sub-areas in three Danish municipalities (both single and multi-family house areas). In total 17 tonnes of waste were sorted into 10–50 waste fractions, organised according to a three-level (tiered approach) facilitating comparison of the waste data between individual sub-areas with different fractionation (waste from one municipality was sorted at “Level III”, e.g. detailed, while the two others were sorted only at “Level I”). The results showed that residual household waste mainly contained food waste (42 ± 5%, mass per wet basis) and miscellaneous combustibles (18 ± 3%, mass per wet basis). The residual household waste generation rate in the study areas was 3–4 kg per person per week. Statistical analyses revealed that the waste composition was independent of variations in the waste generation rate. Both, waste composition and waste generation rates were statistically similar for each of the three municipalities. While the waste generation rates were similar for each of the two housing types (single

  9. Municipal solid waste composition: Sampling methodology, statistical analyses, and case study evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Edjabou, Maklawe Essonanawe, E-mail: vine@env.dtu.dk [Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Jensen, Morten Bang; Götze, Ramona; Pivnenko, Kostyantyn [Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Petersen, Claus [Econet AS, Omøgade 8, 2.sal, 2100 Copenhagen (Denmark); Scheutz, Charlotte; Astrup, Thomas Fruergaard [Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

    2015-02-15

    Highlights: • Tiered approach to waste sorting ensures flexibility and facilitates comparison of solid waste composition data. • Food and miscellaneous wastes are the main fractions contributing to the residual household waste. • Separation of food packaging from food leftovers during sorting is not critical for determination of the solid waste composition. - Abstract: Sound waste management and optimisation of resource recovery require reliable data on solid waste generation and composition. In the absence of standardised and commonly accepted waste characterisation methodologies, various approaches have been reported in literature. This limits both comparability and applicability of the results. In this study, a waste sampling and sorting methodology for efficient and statistically robust characterisation of solid waste was introduced. The methodology was applied to residual waste collected from 1442 households distributed among 10 individual sub-areas in three Danish municipalities (both single and multi-family house areas). In total 17 tonnes of waste were sorted into 10–50 waste fractions, organised according to a three-level (tiered approach) facilitating comparison of the waste data between individual sub-areas with different fractionation (waste from one municipality was sorted at “Level III”, e.g. detailed, while the two others were sorted only at “Level I”). The results showed that residual household waste mainly contained food waste (42 ± 5%, mass per wet basis) and miscellaneous combustibles (18 ± 3%, mass per wet basis). The residual household waste generation rate in the study areas was 3–4 kg per person per week. Statistical analyses revealed that the waste composition was independent of variations in the waste generation rate. Both, waste composition and waste generation rates were statistically similar for each of the three municipalities. While the waste generation rates were similar for each of the two housing types (single

  10. Solid polymer electrolyte composite membrane comprising a porous support and a solid polymer electrolyte including a dispersed reduced noble metal or noble metal oxide

    Science.gov (United States)

    Liu, Han; Mittelsteadt, Cortney K; Norman, Timothy J; Griffith, Arthur E; LaConti, Anthony B

    2015-02-24

    A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a thin, rigid, dimensionally-stable, non-electrically-conducting support, the support having a plurality of cylindrical, straight-through pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores are unevenly distributed, with some or no pores located along the periphery and more pores located centrally. The pores are completely filled with a solid polymer electrolyte, the solid polymer electrolyte including a dispersed reduced noble metal or noble metal oxide. The solid polymer electrolyte may also be deposited over the top and/or bottom surfaces of the support.

  11. Updating and testing of a Finnish method for mixed municipal solid waste composition studies.

    Science.gov (United States)

    Liikanen, M; Sahimaa, O; Hupponen, M; Havukainen, J; Sorvari, J; Horttanainen, M

    2016-06-01

    More efficient recycling of municipal solid waste (MSW) is an essential precondition for turning Europe into a circular economy. Thus, the recycling of MSW must increase significantly in several member states, including Finland. This has increased the interest in the composition of mixed MSW. Due to increased information needs, a method for mixed MSW composition studies was introduced in Finland in order to improve the national comparability of composition study results. The aim of this study was to further develop the method so that it corresponds to the information needed about the composition of mixed MSW and still works in practice. A survey and two mixed MSW composition studies were carried out in the study. According to the responses of the survey, the intensification of recycling, the landfill ban on organic waste and the producer responsibility for packaging waste have particularly influenced the need for information about the composition of mixed MSW. The share of biowaste in mixed MSW interested the respondents most. Additionally, biowaste proved to be the largest waste fraction in mixed MSW in the composition studies. It constituted over 40% of mixed MSW in both composition studies. For these reasons, the classification system of the method was updated by further defining the classifications of biowaste. The classifications of paper as well as paperboard and cardboard were also updated. The updated classification system provides more information on the share of avoidable food waste and waste materials suitable for recycling in mixed MSW. The updated method and the information gained from the composition studies are important in ensuring that the method will be adopted by municipal waste management companies and thus used widely in Finland. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Autonomous Propellant Loading Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The AES Autonomous Propellant Loading (APL) project consists of three activities. The first is to develop software that will automatically control loading of...

  13. Modeling Propellant Tank Dynamics

    Data.gov (United States)

    National Aeronautics and Space Administration — The main objective of my work will be to develop accurate models of self-pressurizing propellant tanks for use in designing hybrid rockets. The first key goal is to...

  14. A Li-Garnet composite ceramic electrolyte and its solid-state Li-S battery

    Science.gov (United States)

    Huang, Xiao; Liu, Cai; Lu, Yang; Xiu, Tongping; Jin, Jun; Badding, Michael E.; Wen, Zhaoyin

    2018-04-01

    A high strength Li-Garnet solid electrolyte composite ceramic is successfully prepared via conventional solid state method with Li6.4La3Zr1.4Ta0.6O12 and nano MgO powders. Well sintered ceramic pellets and bars are obtained with 0-9 wt.% MgO. Fracture strength is approximately 135 MPa for composite ceramics with 5-9 wt.% MgO, which is ∼50% higher than that of pure Li6.4La3Zr1.4Ta0.6O12 (90 MPa). Lithium-ion conductivity of the composite is above 5 × 10-4 S cm-1 at room temperature; comparable to the pure Li6.4La3Zr1.4Ta0.6O12 material. SEM cross-sections of the composite ceramic shows a much more uniform microstructure comparing with pure ones, owing to the grain growth inhibition effect of the MgO second phase. A battery cell consisting of Li/composite ceramics/Sulfur-Carbon at 25 °C exhibits a capacity of 685 mAh g-1 at 0.2 C at the 200th cycle, while maintaining a coulombic efficiency of 100%. These results indicate that the composite ceramic Li6.4La3Zr1.4Ta0.6O12-MgO is promising for the production of electrolyte membrane and fabrication of Li-Sulfur batteries.

  15. Statistical analysis of solid waste composition data: Arithmetic mean, standard deviation and correlation coefficients.

    Science.gov (United States)

    Edjabou, Maklawe Essonanawe; Martín-Fernández, Josep Antoni; Scheutz, Charlotte; Astrup, Thomas Fruergaard

    2017-11-01

    Data for fractional solid waste composition provide relative magnitudes of individual waste fractions, the percentages of which always sum to 100, thereby connecting them intrinsically. Due to this sum constraint, waste composition data represent closed data, and their interpretation and analysis require statistical methods, other than classical statistics that are suitable only for non-constrained data such as absolute values. However, the closed characteristics of waste composition data are often ignored when analysed. The results of this study showed, for example, that unavoidable animal-derived food waste amounted to 2.21±3.12% with a confidence interval of (-4.03; 8.45), which highlights the problem of the biased negative proportions. A Pearson's correlation test, applied to waste fraction generation (kg mass), indicated a positive correlation between avoidable vegetable food waste and plastic packaging. However, correlation tests applied to waste fraction compositions (percentage values) showed a negative association in this regard, thus demonstrating that statistical analyses applied to compositional waste fraction data, without addressing the closed characteristics of these data, have the potential to generate spurious or misleading results. Therefore, ¨compositional data should be transformed adequately prior to any statistical analysis, such as computing mean, standard deviation and correlation coefficients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Computer Simulations of Composite Electrodes in Solid-Oxide Fuel-Cells

    Energy Technology Data Exchange (ETDEWEB)

    Sunde, Svein

    1999-07-01

    Fuel cells are devices for converting the combined chemical (free) energy of fuels and oxygen (air) directly to electrical energy without relying on the dynamic action of steam heated by reacting fuel-oxygen mixtures, like in steam turbines, or of the reacting gas mixtures themselves, like in gas turbines. The basic rationale for fuel cells is their high efficiencies as compared to indirect-conversion methods. Fuel cells are currently being considered for a number of applications, among them de-centralised power supply. Fuel cells come in five basic types and are usually classified according to the type of electrolyte used, which in turn to a significant degree limits the options for anode and cathode materials. The solid-oxide fuel-cell (SOFC) , with which this thesis is concerned, is thus named after its oxide electrolyte, typically the oxide-ion conducting material yttria-stabilised zirconia (YSZ). While the cathode of an SOFC is often uniform in chemical composition (or at least intended to be), various problems of delamination, cracking etc. associated with the use of metallic anode electrocatalysts led to the development of composite SOFC anodes. Porous anodes consisting of Ni and YSZ particles in roughly 50/50 wt-% mixtures are now almost standard with any SOFC-development programme. The designer of composite SOFC electrodes is faced with at least three, interrelated questions: (1) What will be the optimum microstructure and composition of the composite electrode? (2) If the structure changes during operation, as is often observed, what will be the consequences for the internal losses in the cell? (3) How do we interpret electrochemical and conductivity measurements with regard to structure and composition? It is the primary purpose of this thesis to provide a framework for modelling the electrochemical and transport properties of composite electrodes for SOFC, and to arrive at some new insights that cannot be offered by experiment alone. Emphasis is put on

  17. JANNAF 28th Propellant Development and Characterization Subcommittee and 17th Safety and Environmental Protection Subcommittee Joint Meeting. Volume 1

    Science.gov (United States)

    Cocchiaro, James E. (Editor); Mulder, Edwin J. (Editor); Gomez-Knight, Sylvia J. (Editor)

    1999-01-01

    This volume contains 37 unclassified/unlimited-distribution technical papers that were presented at the JANNAF 28th Propellant Development & Characterization Subcommittee (PDCS) and 17th Safety & Environmental Protection Subcommittee (S&EPS) Joint Meeting, held 26-30 April 1999 at the Town & Country Hotel and the Naval Submarine Base, San Diego, California. Volume II contains 29 unclassified/limited-distribution papers that were presented at the 28th PDCS and 17th S&EPS Joint Meeting. Volume III contains a classified paper that was presented at the 28th PDCS Meeting on 27 April 1999. Topics covered in PDCS sessions include: solid propellant rheology; solid propellant surveillance and aging; propellant process engineering; new solid propellant ingredients and formulation development; reduced toxicity liquid propellants; characterization of hypergolic propellants; and solid propellant chemical analysis methods. Topics covered in S&EPS sessions include: space launch range safety; liquid propellant hazards; vapor detection methods for toxic propellant vapors and other hazardous gases; toxicity of propellants, ingredients, and propellant combustion products; personal protective equipment for toxic liquid propellants; and demilitarization/treatment of energetic material wastes.

  18. Disposal of Liquid Propellants

    Science.gov (United States)

    1990-03-13

    propellant includes an oxi- dizer (hydroxylammoniuin nitrate), a fuel (triethanolammonium nitrate), and water . In an- ticipation of widespread (both...are also included. 20. DISTRIBUTION/ AVAILABILIT ’." OF ABMTRACT 21 ABSTRACT SECURITY CLASSIF.CATICIN IUNCLASSIFIEDIUNLIMITED 0 SAME AS RPT. 0 OTIC...trieth- anolammoiur nitrate), anG water . In anticipation of widespread (both conti- nental U.S. and abroac) use of the propellant, USATHAMA began a

  19. The influence of precipitation temperature on the properties of ceria–zirconia solid solution composites

    International Nuclear Information System (INIS)

    Cui, Yajuan; Fang, Ruimei; Shang, Hongyan; Shi, Zhonghua; Gong, Maochu; Chen, Yaoqiang

    2015-01-01

    Highlights: • The crystallite size of precipitate increases as the precipitation temperature rises. • The stack of large crystallite can form nanoparticles with big pore size. • Big pore sizes are advantageous to improve the thermal stability. • Phase segregation is restricted in CZ solid solution precipitated at 70 °C. • The reducibility and OSC of the solid solution precipitated at 70 °C are improved. - Abstract: The ceria–zirconia composites (CZ) with a Ce/Zr mass ratio of 1/1 were synthesized by a back-titration method, in which the influence of precipitation temperature on the properties of ceria–zirconia precipitates was investigated. The resulting precipitation and mixed oxides at different precipitation temperatures were then characterized by a range of techniques, including textural properties, X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), H 2 -temperature programmed reduction (H 2 -TPR) as well as oxygen storage capacity (OSC) measurement. The results revealed that ceria–zirconia composites were formed as solid solution and such structure is favored of thermostability and texture properties. In particular, the composite CZ-70 synthesized at 70 °C exhibited prominent thermostability with a surface area of 32 m 2 /g as well as a pore volume of 0.15 cc/g after aging treatment at 1000 °C for 5 h. And this was found to be associated with the wider pore size distribution which maybe owed to the formation of large crystal at the primary stage of precipitation. Additionally, the composite CZ-70 showed excellent reduction property and OSC benefiting from stable texture and structure

  20. Tribological and mechanical behaviors of polyamide 6/glass fiber composite filled with various solid lubricants.

    Science.gov (United States)

    Li, Duxin; Xie, Ying; Li, Wenjuan; You, Yilan; Deng, Xin

    2013-01-01

    The effects of polytetrafluoroethylene (PTFE), graphite, ultrahigh molecular weight polyethylene (UHMWPE), and their compounds on mechanical and tribological properties of glass-fiber-reinforced polyamide 6 (PA6/GF) were studied. The polymeric materials were blended using twin-screw extruder and subsequently injection molded for test samples. Mechanical properties were investigated in terms of hardness, tensile strength, and impact strength. Friction and wear experiments were run under ambient conditions at a rotating speed of 200 rpm and load of 100 N. The morphologies of the worn surfaces were also observed with scanning electron microscope. The results showed that graphite could increase the tensile strength of PA6/GF-15 composite, but the material became soft. Graphite/UHMWPE complex solid lubricants were effective in increasing the already high impact strength of PA6/GF-15 composite. 5% PTFE gave the maximum reduction in the coefficient of friction. However, PTFE/UHMWPE complex solid lubricants were the best choice for improving both friction and wear behaviors due to the lower friction coefficient and mass wear rate. Moreover, the worn surface of PA6 composites revealed that adhesive wear, abrasive wear, and fatigue wear occurred in this study.

  1. Investigation of Different Colloidal Porous Silicon Solutions and Their Composite Solid Matrix Rods by Optical Techniques

    Science.gov (United States)

    Khan, M. Naziruddin; Aldalbahi, Ali; Almohammedi, Abdullah

    2018-03-01

    Colloidal porous silicon (PSi) in different solvents was synthesized by simple chemical etching. Colloidal solutions were then prepared using different quantities of silicon wafer pieces (Pcs) and chloroplatinic (Pt) acid in catalyst solution. The effect on the properties of the colloidal solutions and composite rods were investigated using various optical characterization techniques. Absorption and photoluminescence (PL) intensity of the colloidal PSi solutions are observed to depend on the quantity of wafer Pcs, the Pt-solution, and the porosity formation on the wafer surface. The morphological structure of the PSi in a solvent and the solid-rod environments were studied using field-emission scanning electron microscopy (FE-SEM) and were observed to have different structures. A mono-oriented structure of PSi exists in tetrahydrofuran, which has stereo orientation in dioxane and dimethylsulfoxide (approximately 5-8 nm as confirmed using high resolution transmission electron microscopy). Subsequently, some colloidal PSi solutions were directly embedded in three types of sol-gel-based matrices, silica, ormosils (or organically modified silica) and polymer, which easily generated solid rods. Spontaneous emission (SE) of the PSi solutions and their composite rods were examined using a high power picosecond 355 nm laser source. The emitted PL and SE signals of the colloidal PSi solutions were dependent on the Pt volume, nature of the solvent, quantity of Si wafer piece, and pumping energy. The response of SE signals from the PSi composites rods is an interesting phenomenon, and such nanocomposites may be used for future research on light amplification.

  2. Composite electrolyte with proton conductivity for low-temperature solid oxide fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Raza, Rizwan, E-mail: razahussaini786@gmail.com [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Energy Technology, Royal Institute of Technology, KTH, Stockholm 10044 (Sweden); Ahmed, Akhlaq; Akram, Nadeem; Saleem, Muhammad; Niaz Akhtar, Majid; Ajmal Khan, M.; Abbas, Ghazanfar; Alvi, Farah; Yasir Rafique, M. [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Sherazi, Tauqir A. [Department of Chemistry, COMSATS Institute of Information Technology, Abbotabad 22060 (Pakistan); Shakir, Imran [Sustainable Energy Technologies (SET) center, College of Engineering, King Saud University, PO-BOX 800, Riyadh 11421 (Saudi Arabia); Mohsin, Munazza [Department of Physics, Lahore College for Women University, Lahore, 54000 (Pakistan); Javed, Muhammad Sufyan [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Zhu, Bin, E-mail: binzhu@kth.se, E-mail: zhubin@hubu.edu.cn [Department of Energy Technology, Royal Institute of Technology, KTH, Stockholm 10044 (Sweden); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Faculty of Physics and Electronic Science/Faculty of Computer and Information, Hubei University, Wuhan, Hubei 430062 (China)

    2015-11-02

    In the present work, cost-effective nanocomposite electrolyte (Ba-SDC) oxide is developed for efficient low-temperature solid oxide fuel cells (LTSOFCs). Analysis has shown that dual phase conduction of O{sup −2} (oxygen ions) and H{sup +} (protons) plays a significant role in the development of advanced LTSOFCs. Comparatively high proton ion conductivity (0.19 s/cm) for LTSOFCs was achieved at low temperature (460 °C). In this article, the ionic conduction behaviour of LTSOFCs is explained by carrying out electrochemical impedance spectroscopy measurements. Further, the phase and structure analysis are investigated by X-ray diffraction and scanning electron microscopy techniques. Finally, we achieved an ionic transport number of the composite electrolyte for LTSOFCs as high as 0.95 and energy and power density of 90% and 550 mW/cm{sup 2}, respectively, after sintering the composite electrolyte at 800 °C for 4 h, which is promising. Our current effort toward the development of an efficient, green, low-temperature solid oxide fuel cell with the incorporation of high proton conductivity composite electrolyte may open frontiers in the fields of energy and fuel cell technology.

  3. Tribological and Mechanical Behaviors of Polyamide 6/Glass Fiber Composite Filled with Various Solid Lubricants

    Directory of Open Access Journals (Sweden)

    Duxin Li

    2013-01-01

    Full Text Available The effects of polytetrafluoroethylene (PTFE, graphite, ultrahigh molecular weight polyethylene (UHMWPE, and their compounds on mechanical and tribological properties of glass-fiber-reinforced polyamide 6 (PA6/GF were studied. The polymeric materials were blended using twin-screw extruder and subsequently injection molded for test samples. Mechanical properties were investigated in terms of hardness, tensile strength, and impact strength. Friction and wear experiments were run under ambient conditions at a rotating speed of 200 rpm and load of 100 N. The morphologies of the worn surfaces were also observed with scanning electron microscope. The results showed that graphite could increase the tensile strength of PA6/GF-15 composite, but the material became soft. Graphite/UHMWPE complex solid lubricants were effective in increasing the already high impact strength of PA6/GF-15 composite. 5% PTFE gave the maximum reduction in the coefficient of friction. However, PTFE/UHMWPE complex solid lubricants were the best choice for improving both friction and wear behaviors due to the lower friction coefficient and mass wear rate. Moreover, the worn surface of PA6 composites revealed that adhesive wear, abrasive wear, and fatigue wear occurred in this study.

  4. Composite electrolyte with proton conductivity for low-temperature solid oxide fuel cell

    Science.gov (United States)

    Raza, Rizwan; Ahmed, Akhlaq; Akram, Nadeem; Saleem, Muhammad; Niaz Akhtar, Majid; Sherazi, Tauqir A.; Ajmal Khan, M.; Abbas, Ghazanfar; Shakir, Imran; Mohsin, Munazza; Alvi, Farah; Javed, Muhammad Sufyan; Yasir Rafique, M.; Zhu, Bin

    2015-11-01

    In the present work, cost-effective nanocomposite electrolyte (Ba-SDC) oxide is developed for efficient low-temperature solid oxide fuel cells (LTSOFCs). Analysis has shown that dual phase conduction of O-2 (oxygen ions) and H+ (protons) plays a significant role in the development of advanced LTSOFCs. Comparatively high proton ion conductivity (0.19 s/cm) for LTSOFCs was achieved at low temperature (460 °C). In this article, the ionic conduction behaviour of LTSOFCs is explained by carrying out electrochemical impedance spectroscopy measurements. Further, the phase and structure analysis are investigated by X-ray diffraction and scanning electron microscopy techniques. Finally, we achieved an ionic transport number of the composite electrolyte for LTSOFCs as high as 0.95 and energy and power density of 90% and 550 mW/cm2, respectively, after sintering the composite electrolyte at 800 °C for 4 h, which is promising. Our current effort toward the development of an efficient, green, low-temperature solid oxide fuel cell with the incorporation of high proton conductivity composite electrolyte may open frontiers in the fields of energy and fuel cell technology.

  5. Municipal solid waste composition: Sampling methodology, statistical analyses, and case study evaluation

    DEFF Research Database (Denmark)

    Edjabou, Vincent Maklawe Essonanawe; Jensen, Morten Bang; Götze, Ramona

    2015-01-01

    Sound waste management and optimisation of resource recovery require reliable data on solid waste generation and composition. In the absence of standardised and commonly accepted waste characterisation methodologies, various approaches have been reported in literature. This limits both...... comparability and applicability of the results. In this study, a waste sampling and sorting methodology for efficient and statistically robust characterisation of solid waste was introduced. The methodology was applied to residual waste collected from 1442 households distributed among 10 individual sub......-areas in three Danish municipalities (both single and multi-family house areas). In total 17 tonnes of waste were sorted into 10-50 waste fractions, organised according to a three-level (tiered approach) facilitating,comparison of the waste data between individual sub-areas with different fractionation (waste...

  6. Formation of soft magnetic high entropy amorphous alloys composites containing in situ solid solution phase

    Science.gov (United States)

    Wei, Ran; Sun, Huan; Chen, Chen; Tao, Juan; Li, Fushan

    2018-03-01

    Fe-Co-Ni-Si-B high entropy amorphous alloys composites (HEAACs), which containing high entropy solid solution phase in amorphous matrix, show good soft magnetic properties and bending ductility even in optimal annealed state, were successfully developed by melt spinning method. The crystallization phase of the HEAACs is solid solution phase with body centered cubic (BCC) structure instead of brittle intermetallic phase. In addition, the BCC phase can transformed into face centered cubic (FCC) phase with temperature rise. Accordingly, Fe-Co-Ni-Si-B high entropy alloys (HEAs) with FCC structure and a small amount of BCC phase was prepared by copper mold casting method. The HEAs exhibit high yield strength (about 1200 MPa) and good plastic strain (about 18%). Meanwhile, soft magnetic characteristics of the HEAs are largely reserved from HEAACs. This work provides a new strategy to overcome the annealing induced brittleness of amorphous alloys and design new advanced materials with excellent comprehensive properties.

  7. Foam behavior of solid glass spheres – Zn22Al2Cu composites under compression stresses

    International Nuclear Information System (INIS)

    Aragon-Lezama, J.A.; Garcia-Borquez, A.; Torres-Villaseñor, G.

    2015-01-01

    Solid glass spheres – Zn22Al2Cu composites, having different densities and microstructures, were elaborated and studied under compression. Their elaboration process involves alloy melting, spheres submersion into the liquid alloy and finally air cooling. The achieved composites with densities 2.6884, 2.7936 and 3.1219 g/cm 3 were studied in casting and thermally induced, fine-grain matrix microstructures. Test samples of the composites were compressed at a 10 −3 s −1 strain rate, and their microstructure characterized before and after compression by using optical and scanning electron microscopes. Although they exhibit different compression behavior depending on their density and microstructure, all of them show an elastic region at low strains, reach their maximum stress (σ max ) at hundreds of MPa before the stress fall or collapse up to a lowest yield point (LYP), followed by an important plastic deformation at nearly constant stress (σ p ): beyond this plateau, an extra deformation can be limitedly reached only by a significant stress increase. This behavior under compression stresses is similar to that reported for metal foams, being the composites with fine microstructure which nearest behave to metal foams under this pattern. Nevertheless, the relative values of the elastic modulus, and maximum and plateau stresses do not follow the Ashby equations by changing the relative density. Generally, the studied composites behave as foams under compression, except for their peculiar parameters values (σ max , LYP, and σ p )

  8. Mathematical micro-model of a solid oxide fuel cell composite cathode

    International Nuclear Information System (INIS)

    Kenney, B.; Karan, K.

    2004-01-01

    In a solid oxide fuel cell (SOFC), the cathode processes account for a majority of the overall electrochemical losses. A composite cathode comprising a mixture of ion-conducting electrolyte and electron-conducting electro-catalyst can help minimize cathode losses provided microstructural parameters such as particle-size, composition, and porosity are optimized. The cost of composite cathode research can be greatly reduced by incorporating mathematical models into the development cycle. Incorporated with reliable experimental data, it is possible to conduct a parametric study using a model and the predicted results can be used as guides for component design. Many electrode models treat the cathode process simplistically by considering only the charge-transfer reaction for low overpotentials or the gas-diffusion at high overpotentials. Further, in these models an average property of the cathode internal microstructure is assumed. This paper will outline the development of a 1-dimensional SOFC composite cathode micro-model and the experimental procedures for obtaining accurate parameter estimates. The micro-model considers the details of the cathode microstructure such as porosity, composition and particle-size of the ionic and electronic phases, and their interrelationship to the charge-transfer reaction and mass transport processes. The micro-model will be validated against experimental data to determine its usefulness for performance prediction. (author)

  9. Thermal characterization of polymer matrix composites containing microencapsulated paraffin in solid or liquid state

    International Nuclear Information System (INIS)

    Sari-Bey, Sana; Fois, Magali; Krupa, Igor; Ibos, Laurent; Benyoucef, Boumédiène

    2014-01-01

    Highlights: • Thermal characterization of PCL/Micronal composites. • Melting enthalpy and heat capacity measured by DSC. • Interest: have measured thermal properties at different temperatures. • Thermophysical properties measurement temperatures chosen outside phase changes. • Characteristics useful to model composites heat transfer for LHTES applications. - Abstract: This work focuses on the study of heat transfer mechanisms in composites materials which may be used for Latent Heat Thermal Energy Storage applications. These composites contain phase change material (PCM) which can absorb and release energy during thermal cycling. PCM’s used here are paraffins microencapsulated in poly(methylmethacrylate); microencapsulation avoids the flow of paraffin when it is in the liquid state. Samples with different paraffin weight fractions and particles shape and distribution were studied in this work. Scanning Electron Microscopy and Differential Scanning Calorimetry were used to determine morphology and perform measurements of phase changes temperatures, enthalpies and heat capacity respectively. Further, a periodic method (DICO) allowed measuring thermal conductivity (λ) and diffusivity (a) of the composites at temperatures below and above of the paraffin phase change from crystalline solid to isotropic liquid

  10. Fabrication of metal matrix composite by semi-solid powder processing

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yufeng [Iowa State Univ., Ames, IA (United States)

    2011-01-01

    Various metal matrix composites (MMCs) are widely used in the automotive, aerospace and electrical industries due to their capability and flexibility in improving the mechanical, thermal and electrical properties of a component. However, current manufacturing technologies may suffer from insufficient process stability and reliability and inadequate economic efficiency and may not be able to satisfy the increasing demands placed on MMCs. Semi-solid powder processing (SPP), a technology that combines traditional powder metallurgy and semi-solid forming methods, has potential to produce MMCs with low cost and high efficiency. In this work, the analytical study and experimental investigation of SPP on the fabrication of MMCs were explored. An analytical model was developed to understand the deformation mechanism of the powder compact in the semi-solid state. The densification behavior of the Al6061 and SiC powder mixtures was investigated with different liquid fractions and SiC volume fractions. The limits of SPP were analyzed in terms of reinforcement phase loading and its impact on the composite microstructure. To explore adoption of new materials, carbon nanotube (CNT) was investigated as a reinforcing material in aluminum matrix using SPP. The process was successfully modeled for the mono-phase powder (Al6061) compaction and the density and density distribution were predicted. The deformation mechanism at low and high liquid fractions was discussed. In addition, the compaction behavior of the ceramic-metal powder mixture was understood, and the SiC loading limit was identified by parametric study. For the fabrication of CNT reinforced Al6061 composite, the mechanical alloying of Al6061-CNT powders was first investigated. A mathematical model was developed to predict the CNT length change during the mechanical alloying process. The effects of mechanical alloying time and processing temperature during SPP were studied on the mechanical, microstructural and

  11. Tribological properties of solid lubricants filled glass fiber reinforced polyamide 6 composites

    International Nuclear Information System (INIS)

    Li, Du-Xin; You, Yi-Lan; Deng, Xin; Li, Wen-Juan; Xie, Ying

    2013-01-01

    Highlights: ► The tribological properties of GF/PA6 improved by the incorporation of PTFE. ► PTFE and UHMWPE exhibited a synergism effect on reducing friction coefficient. ► Solid lubricants enlarged the range of applied velocity for GF/PA6 composite. - Abstract: The main purpose of this paper is to further optimize the tribological properties of the glass fiber reinforced PA6 (GF/PA6,15/85 by weight) for high performance friction materials using single or combinative solid lubricants such as Polytetrafluroethylene (PTFE), ultra-high molecular weight polyethylene (UHMWPE) and the combination of both of them. Various polymer blends, where GF/PA6 acts as the polymer matrix and solid lubricants as the dispersed phase were prepared by injection molding. The tribological properties of these materials and the synergism as a result of the incorporation of both PTFE and UHMWPE were investigated. The results showed that, at a load of 40 N and a velocity of 200 rpm, PTFE was effective in improving the tribological capabilities of matrix material. On the contrary, UHMWPE was not conductive to maintain the structure integrity of GF/PA6 composite and harmful to the friction and wear properties. The combination of PTFE and UHMWPE showed synergism on further reducing the friction coefficient of the composites filled with either PTFE or UHMWPE only. Effects of load and velocity on tribological behavior were also discussed. To further understand the wear mechanism, the worn surfaces were examined by scanning electron microscopy

  12. Changes in volatile compound composition of Antrodia camphorata during solid state fermentation.

    Science.gov (United States)

    Xia, Yongjun; Zhang, Baorong; Li, Weijiang; Xu, Ganrong

    2011-10-01

    Although the volatiles present in mushrooms and fungi have been investigated by many researchers, including Antrodia camphorata in submerged fermentation, there are few data available regarding changes in volatile compounds during fermentation. Our research has revealed that solid state fermentation of A. camphorata is highly odiferous compared with submerged cultures and the odor changed with increasing culture time. Therefore the aim of this study was to investigate the changes in volatile compound composition of A. camphorata during solid state fermentation. Altogether, 124 major volatile compounds were identified. The volatile compounds produced by A. camphorata during growth in solid state fermentation were quite different. Oct-1-en-3-ol, octan-3-one and methyl 2-phenylacetate were predominant in exponential growth phase production, while the dominant volatiles produced in stationary phase were octan-3-one and methyl 2-phenylacetate. In stationary phase, lactone compounds in A. camphorata, such as 5-butyloxolan-2-one, 5-heptyloxolan-2-one, 6-heptyloxan-2-one, contributed greatly to peach and fruit-like flavor. Terpene and terpene alcohol compounds, such as 1-terpineol, L-linalool, T-cadinol, (E, E)-farnesol, β-elemene, cis-α-bisabolene and α-muurolene, made different contributions to herbal fresh aroma in A. camphorata. Nineteen volatile sesquiterpenes were detected from solid state fermentation of A. camphorata. The compounds 5-n-butyl-5H-furan-2-one, β-ionone, (-)-caryophyllene oxide, aromadendrene oxide, diepi-α-cedrene epoxide, β-elemene, α-selinene, α-muurolene, azulene, germacrene D, γ-cadinene and 2-methylpyrazine have not hitherto been reported in A. camphorata. The preliminary results suggest that the aroma-active compounds produced by A camphorata in solid state fermentation might serve as an important source of natural aroma compounds for the food and cosmetic industries or antibiotic activity compounds. The sesquiterpenes could be

  13. Propellers in Saturn's rings

    Science.gov (United States)

    Sremcevic, M.; Stewart, G. R.; Albers, N.; Esposito, L. W.

    2013-12-01

    Theoretical studies and simulations have demonstrated the effects caused by objects embedded in planetary rings. Even if the objects are too small to be directly observed, each creates a much larger gravitational imprint on the surrounding ring material. These strongly depend on the mass of the object and range from "S" like propeller-shaped structures for about 100m-sized icy bodies to the opening of circumferential gaps as in the case of the embedded moons Pan and Daphnis and their corresponding Encke and Keeler Gaps. Since the beginning of the Cassini mission many of these smaller objects (~data from Cassini Ultraviolet Imaging Spectrograph (UVIS) and Imaging Science Subsystem (ISS) experiments. We show evidence that B ring seems to harbor two distinct populations of propellers: "big" propellers covering tens of degrees in azimuth situated in the densest part of B ring, and "small" propellers in less dense inner B ring that are similar in size and shape to known A ring propellers. The population of "big" propellers is exemplified with a single object which is observed for 5 years of Cassini data. The object is seen as a very elongated bright stripe (40 degrees wide) in unlit Cassini images, and dark stripe in lit geometries. In total we report observing the feature in images at 18 different epochs between 2005 and 2010. In UVIS occultations we observe this feature as an optical depth depletion in 14 out of 93 occultation cuts at corrotating longitudes compatible with imaging data. Combining the available Cassini data we infer that the object is a partial gap located at r=112,921km embedded in the high optical depth region of the B ring. The gap moves at Kepler speed appropriate for its radial location. Radial offsets of the gap locations in UVIS occultations are consistent with an asymmetric propeller shape. The asymmetry of the observed shape is most likely a consequence of the strong surface mass density gradient, as the feature is located at an edge between

  14. High strength Ni based composite reinforced by solid solution W(Al) obtained by powder metallurgy

    International Nuclear Information System (INIS)

    Zhao Bo; Zhu Changjun; Ma Xianfeng; Zhao Wei; Tang Huaguo; Cai Shuguang; Qiao Zhuhui

    2007-01-01

    The solid-solution-particle reinforced W(Al)-Ni composites were successfully fabricated by using mechanical alloying (MA) and hot-pressing (HP) technique when the content of Ni is between 45 wt% and 55 wt%. Besides, samples of various original component ratio of Al 50 W 50 to Ni have been fabricated, and the corresponding microcomponents and mechanical properties such as microhardness, ultimate tensile strength and elongation were characterized and discussed. The optimum ultimate tensile strength under the experiment conditions is 1868 MPa with elongation of 10.21% and hardness of 6.62 GPa. X-ray diffraction (XRD), FE-SEM and energy dispersive analysis of X-rays (EDS) were given to analysis the components and morphology of the composite bulk specimens

  15. PHYSICOCHEMICAL PROPERTIES OF THE SOLID COMPONENT OF WELDING AEROSOL. I. PHASE COMPOSITION

    Directory of Open Access Journals (Sweden)

    T. L. Rakitskaya

    2015-02-01

    Full Text Available The phase composition of the solid component of welding aerosol (SCWA obtained as a result of metal welding with electrodes of ANO-4 and TsL-11 types manufactured according to ISO 2560 E432R 21 and ISO E19.9NbB20 standards, respectively, and differing in com-position of their wires and coatings was determined with the help of a Siemens D500 diffrac- a Siemens D500 diffrac-tometer supplied with the manufacturer’s software. Four and thirteen phases were identified in SCWA-ANO-4 and SCWA-TsL-11, respectively. Evaluation of crystallite sizes by the use of the Scherer equation showed that the crystallites formed in the course of welding with a TsL-11 type electrode are larger than those in the case of an ANO-4 type one: 65-89 nm and 30-49 nm, respectively.

  16. The role of microcracking on the crack growth resistance of brittle solids and composites

    International Nuclear Information System (INIS)

    Biner, S.B.

    1994-01-01

    A set of numerical analyses of crack growth was preformed to elucidate the influence of microcracking on the fracture behavior of microcracking brittle solids and composites. The random nucleation, orientation and size effects of discrete nucleating microcracks and resulting interactions are fully accounted for in a hybrid finite element model. The results obtained from the finite element analysis are compared with the continuum description of the microcracking. Although continuum description can provide a reasonable estimation of shielding, it fails to resolve the details of micromechanism of toughening resulting from microcracking, since not every shielding event during the course of crack extension corresponds to an increase in the R-curve. Moreover, as seen in the composite cases, the local events leading to toughening behavior may not be associated with the microcracking even in the presence of a large population of microcracks

  17. Designing Small Propellers for Optimum Efficiency and Low Noise Footprint

    Science.gov (United States)

    2015-06-26

    each one. The GUI contains input boxes for all of the necessary data in order to run QMIL, QPROP, NAFNoise, and to produce Visual Basic ( VBA ) code... VBA macros that will automatically place reference planes for each airfoil section and insert the splined airfoils to their respective reference...Figure 24. Solid propeller exa mple. Figure 25. Hub and spoke propeller design. Figure 26. Alumninum hub design. accessed on May 12, 2015. DC, August

  18. Phase-alternated composite π/2 pulses for solid state quadrupole echo NMR spectroscopy

    International Nuclear Information System (INIS)

    Ramamoorthy, A.; Narasimhan, P.T.

    1991-01-01

    Phase-alternated composite π/2 pulses have been constructed for spin I=1 to overcome quadrupole interaction effects in solid state nuclear magnetic resonance(NMR) spectroscopy. Magnus expansion approach is used to design these sequences in a manner similar to the NMR coherent averaging theory. It is inferred that the symmetric phase-alternated composite π/2 pulses reported here are quite successful in producing quadrupole echo free phase distortions. This effectiveness of the present composite pulses is due to the fact that most of them are of shorter durations as compared to the ones reported in literature. In this theoretical procedure, irreducible spherical tensor operator formalism is employed to simplify the complexity involved in the evaluation of Magnus expansion terms. It has been argued in this paper that composite π/2 pulse sequences for this purpose can also be derived from the broadband inversion π pulses which are designed to compensate electric field gradient(efg) inhomogeniety in spin I=1 nuclear quadrupole resonance(NQR) spectroscopy. (author). 28 refs

  19. Injection dynamics of gelled propellants

    Science.gov (United States)

    Yoon, Changjin

    Gel propellants have been recognized as attractive candidates for future propulsion systems due to the reduced tendency to spill and the energy advantages over solid propellants. One of strong benefits emphasized in gel propellant applications is a throttling capability, but the accurate flow control is more complicated and difficult than with conventional Newtonian propellants because of the unique rheological behaviors of gels. This study is a computational effort directed to enhance understanding of the injector internal flow characteristics for gel propellants under rocket injection conditions. In simulations, the emphasized rheology is a shear-thinning which represents a viscosity decrease with increasing a shear rate. It is described by a generalized Newtonian fluid constitutive equation and Carreau-Yasuda model. Using this rheological model, two injection schemes are considered in the present study: axially-fed and cross-fed injection for single-element and multi-element impinging injectors, respectively. An axisymmetric model is developed to describe the axially-fed injector flows and fully three-dimensional model is utilized to simulate cross-fed injector flows. Under axially-fed injection conditions investigated, three distinct modes, an unsteady, steady, and hydraulic flip mode, are observed and mapped in terms of Reynolds number and orifice design. In an unsteady mode, quasi-periodic oscillations occur near the inlet lip leading mass pulsations and viscosity fluctuations at the orifice exit. This dynamic behavior is characterized using a time-averaged discharge coefficient, oscillation magnitude and frequency by a parametric study with respect to an orifice design, Reynolds number and rheology. As a result, orifice exit flows for gel propellants appear to be significantly influenced by a viscous damping and flow resistance due to a shear thinning behavior and these are observed in each factors considered. Under conditions driven by a manifold crossflow

  20. Seasonal analysis of the generation and composition of solid waste: potential use--a case study.

    Science.gov (United States)

    Aguilar-Virgen, Quetzalli; Taboada-González, Paul; Ojeda-Benítez, Sara

    2013-06-01

    Ensenada health officials lack pertinent information on the sustainable management of solid waste, as do health officials from other developing countries. The aims of this research are: (a) to quantify and analyze the household solid wastes generated in the city of Ensenada, Mexico, and (b) to project biogas production and estimate generation of electrical energy. The characterization study was conducted by socioeconomic stratification in two seasonal periods, and the biogas and electrical energy projections were performed using the version 2.0 Mexico Biogas Model. Per capita solid waste generation was 0.779 ± 0.019 kg per person per day within a 98 % confidence interval. Waste composition is composed mainly of food scraps at 36.25 %, followed by paper and cardboard at 21.85 %, plastic at 12.30 %, disposable diapers at 6.26 %, and textiles at 6.28 %. The maximum capacity for power generation is projected to be 1.90 MW in 2019. Waste generated could be used as an intermediate in different processes such as recycling (41.04 %) and energy recovery (46.63 %). The electrical energy that could be obtained using the biogas generated at the Ensenada sanitary landfill would provide roughly 60 % of the energy needed for street lighting.

  1. Composite cathode materials development for intermediate temperature solid oxide fuel cell systems

    Science.gov (United States)

    Qin, Ya

    Solid oxide fuel cell (SOFC) systems are of particular interest as electrochemical power systems that can operate on various hydrocarbon fuels with high fuel-to-electrical energy conversion efficiency. Within the SOFC stack, La0.8Sr 0.2Ga0.8Mg0.115Co0.085O3-delta (LSGMC) has been reported as an optimized composition of lanthanum gallate based electrolytes to achieve higher oxygen ionic conductivity at intermediate temperatures, i.e., 500-700°C. The electrocatalytic properties of interfaces between LSGMC electrolytes and various candidate intermediate-temperature SOFC cathodes have been investigated. Sm0.5Sr0.5CoO 3-delta (SSC), and La0.6Sr0.4Co0.2Fe 0.8O3-delta (LSCF), in both pure and composite forms with LSGMC, were investigated with regards to both oxygen reduction and evolution, A range of composite cathode compositions, having ratios of SSC (in wt.%) with LSGMC (wt.%) spanning the compositions 9:1, 8:2, 7:3, 6:4 and 5:5, were investigated to determine the optimal cathode-electrolyte interface performance at intermediate temperatures. All LSGMC electrolyte and cathode powders were synthesized using the glycine-nitrate process (GNP). Symmetrical electrochemical cells were investigated with three-electrode linear dc polarization and ac impedance spectroscopy to characterize the kinetics of the interfacial reactions in detail. Composite cathodes were found to perform better than the single phase cathodes due to significantly reduced polarization resistances. Among those composite SSC-LSGMC cathodes, the 7:3 composition has demonstrated the highest current density at the equivalent overpotential values, indicating that 7:3 is an optimal mixing ratio of the composite cathode materials to achieve the best performance. For the composite SC-LSGMC cathode/LSGMC interface, the cathodic overpotential under 1 A/cm2 current density was as low as 0.085 V at 700°C, 0.062V at 750°C and 0.051V at 800°C in air. Composite LSCF-LSGMC cathode/LSGMC interfaces were found to have

  2. Technology of foamed propellants

    Energy Technology Data Exchange (ETDEWEB)

    Boehnlein-Mauss, Jutta; Kroeber, Hartmut [Fraunhofer Institut fuer Chemische Technologie ICT, Pfinztal (Germany)

    2009-06-15

    Foamed propellants are based on crystalline explosives bonded in energetic reaction polymers. Due to their porous structures they are distinguished by high burning rates. Energy content and material characteristics can be varied by using different energetic fillers, energetic polymers and porous structures. Foamed charges can be produced easily by the reaction injection moulding process. For the manufacturing of foamed propellants a semi-continuous remote controlled production plant in pilot scale was set up and a modified reaction injection moulding process was applied. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  3. Foam behavior of solid glass spheres – Zn22Al2Cu composites under compression stresses

    Energy Technology Data Exchange (ETDEWEB)

    Aragon-Lezama, J.A., E-mail: alja@correo.azc.uam.mx [Departamento de Materiales, Universidad Autónoma Metropolitana-A, Avenida San Pablo 180, Colonia Reynosa Tamaulipas, 02200 México, D.F., México (Mexico); Garcia-Borquez, A., E-mail: a.garciaborquez@yahoo.com.mx [Ciencia de Materiales, ESFM – Instituto Politécnico Nacional, Edif. 9, Unid. Prof. A. Lopez Mateos, Colonia Lindavista, 07738 México, D.F., México (Mexico); Torres-Villaseñor, G., E-mail: gtorres@unam.mx [Departamento de Metálicos y Cerámicos, Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apdo., P 70-360, México, D.F., México (Mexico)

    2015-06-25

    Solid glass spheres – Zn22Al2Cu composites, having different densities and microstructures, were elaborated and studied under compression. Their elaboration process involves alloy melting, spheres submersion into the liquid alloy and finally air cooling. The achieved composites with densities 2.6884, 2.7936 and 3.1219 g/cm{sup 3} were studied in casting and thermally induced, fine-grain matrix microstructures. Test samples of the composites were compressed at a 10{sup −3} s{sup −1} strain rate, and their microstructure characterized before and after compression by using optical and scanning electron microscopes. Although they exhibit different compression behavior depending on their density and microstructure, all of them show an elastic region at low strains, reach their maximum stress (σ{sub max}) at hundreds of MPa before the stress fall or collapse up to a lowest yield point (LYP), followed by an important plastic deformation at nearly constant stress (σ{sub p}): beyond this plateau, an extra deformation can be limitedly reached only by a significant stress increase. This behavior under compression stresses is similar to that reported for metal foams, being the composites with fine microstructure which nearest behave to metal foams under this pattern. Nevertheless, the relative values of the elastic modulus, and maximum and plateau stresses do not follow the Ashby equations by changing the relative density. Generally, the studied composites behave as foams under compression, except for their peculiar parameters values (σ{sub max}, LYP, and σ{sub p})

  4. Optimization of BSCF-SDC composite air electrode for intermediate temperature solid oxide electrolyzer cell

    International Nuclear Information System (INIS)

    Heidari, Dorna; Javadpour, Sirus; Chan, Siew Hwa

    2017-01-01

    Highlights: • Effect of BSCF-SDC composite air electrode on SOEC electrochemical performance. • Effects on performance of BSCF-SDC air electrode, fuel humidity and temperature. • Desired IT-SOEC performance by compositing the BSCF air electrode with SDC. - Abstract: Solid oxide electrolyzer cells (SOECs) are devises which recently have attracted lots of attention due to their advantages. Their high operating temperature leads to mechanical compatibility issues such as thermal expansion mismatch between layers of material in the cell. The aim of this study is to mitigate the issue of thermal expansion mismatch between Ba_0_._5Sr_0_._5Co_0_._8Fe_0_._2O_3_−_δ (BSCF) and samaria doped ceria, Sm_0_._2Ce_0_._8O_1_._9 (SDC), enhance the triple-phase boundaries and improve the adhesion of the electrode to the electrolytes, hence improve the cell performance. To make BSCF more thermo-mechanically compatible with the SDC electrolyte, the formation of a composite electrode by introducing SDC as the compositing material is proposed. In this study, 10 wt.%, 20 wt.%, 30 wt.%, 40 wt.%, and 50 wt.% of commercial SDC powder was mixed with BSCF powder, prepared by sol-gel method, to make the composite air electrode. After successfully synthesizing the BSCF-SDC/YSZ-SDC/Ni-YSZ electrolyzer cell, the electrochemical performance was tested for the intermediate-temperature SOEC (IT-SOEC), over the temperature range of 650–800 °C. The microstructure of each sample was studied by field emission electron microscopy (FESEM, JEOL, JSM 6340F) for possible pin holes. The result of this study proves that the sample with 20% SDC-80% BSCF shows the highest performance among the investigated cells.

  5. Synthesis and ceramic processing of zirconia alumina composites for application as solid oxide fuel cell electrolytes

    International Nuclear Information System (INIS)

    Garcia, Rafael Henrique Lazzari

    2007-01-01

    The global warmness and the necessity to obtain clean energy from alternative methods than petroleum raises the importance of developing cleaner and more efficient systems of energy generation, among then, the solid oxide fuel cell (SOFC). Cubic stabilized zirconia (CSZ) has been the most studied material as electrolyte in SOFC, due to its ionic conductivity and great stability at operation conditions. However, its low fracture toughness difficulties its application as a thin layer, what could lead to an improvement of cell efficiency. In this sense, the alumina addition in CSZ forms a composite, which can shift its mechanical properties, without compromising its electrical properties. In this work, coprecipitation synthesis route and ceramic processing of zirconia-alumina composites were studied, in order to establish optimum conditions to attain high density, homogeneous microstructure, and better mechanical properties than CSZ, without compromising ionic conductivity. For this purpose, composites containing up to 40 wt % of alumina, in a 9 mol % yttria-stabilized zirconia (9Y-CSZ) matrix were evaluated. In order to optimize the synthesis of the composites, a preliminary study of powder obtaining and processing were carried out, at compositions containing 20 wt % of alumina, in 9Y-CSZ. The ceramic powders were characterized by helium picnometry, X-ray diffraction, scanning electronic microscopy, transmission electronic microscopy, thermogravimetry, differential scanning calorimetry, granulometry by laser diffraction and gas adsorption (BET). The characterization of sinterized compacts were performed by X-ray diffraction, scanning electron microscopy, optical microscopy, density measurements, Vickers indentation and impedance spectroscopy. The obtained results show that the alumina addition, in the 9Y-CSZ matrix powders, raises the specific surface area, promotes deagglomeration of powders and elevates the oxides crystallization temperature, requiring higher

  6. Propeller TAP flap

    DEFF Research Database (Denmark)

    Thomsen, Jørn Bo; Bille, Camilla; Wamberg, Peter

    2013-01-01

    major complications needing additional surgery. One flap was lost due to a vascular problem. Breast reconstruction can be performed by a propeller TAP flap without cutting the descending branch of the thoracodorsal vessels. However, the authors would recommend that a small cuff of muscle is left around...

  7. Structure and blood compatibility of highly oriented PLA/MWNTs composites produced by solid hot drawing.

    Science.gov (United States)

    Li, Zhengqiu; Zhao, Xiaowen; Ye, Lin; Coates, Phil; Caton-Rose, Fin; Martyn, Michasel

    2014-03-01

    Highly oriented poly(lactic acid) (PLA)/multi-walled carbon nanotubes (MWNTs) composites were fabricated through solid hot drawing technology in an effort to improve the mechanical properties and blood biocompatibility of PLA as blood-contacting medical devices. It was found that proper MWNTs content and drawing orientation can improve the tensile strength and modulus of PLA dramatically. With the increase in draw ratio, the cold crystallization peak became smaller, and the glass transition and the melting peak of PLA moved to high temperature, while the crystallinity increased, and the grain size decreased, indicating the stress-induced crystallization of PLA during drawing. MWNTs showed a nucleation effect on PLA, leading to the rise in the melting temperature, increase in crystallinity and reduction of spherulite size for the composites. Moreover, the intensity of (002) diffraction of MWNTs increased with draw ratio, indicating that MWNTs were preferentially aligned and oriented during drawing. Microstructure observation demonstrated that PLA matrix had an ordered fibrillar bundle structure, and MWNTs in the composite tended to align parallel to the drawing direction. In addition, the dispersion of MWNTs in PLA was also improved by orientation. Introduction of MWNTs and drawing orientation could significantly enhance the blood compatibility of PLA by prolonging kinetic clotting time, reducing hemolysis ratio and platelet activation.

  8. Solid recovered fuel: influence of waste stream composition and processing on chlorine content and fuel quality.

    Science.gov (United States)

    Velis, Costas; Wagland, Stuart; Longhurst, Phil; Robson, Bryce; Sinfield, Keith; Wise, Stephen; Pollard, Simon

    2012-02-07

    Solid recovered fuel (SRF) produced by mechanical-biological treatment (MBT) of municipal waste can replace fossil fuels, being a CO(2)-neutral, affordable, and alternative energy source. SRF application is limited by low confidence in quality. We present results for key SRF properties centered on the issue of chlorine content. A detailed investigation involved sampling, statistical analysis, reconstruction of composition, and modeling of SRF properties. The total chlorine median for a typical plant during summer operation was 0.69% w/w(d), with lower/upper 95% confidence intervals of 0.60% w/w(d) and 0.74% w/w(d) (class 3 of CEN Cl indicator). The average total chlorine can be simulated, using a reconciled SRF composition before shredding to limit for ash content marginally below the 20% w/w(d) deemed suitable for certain power plants; and a lower 95% confidence limit of net calorific value (NCV) at 14.5 MJ kg(ar)(-1). The data provide, for the first time, a high level of confidence on the effects of SRF composition on its chlorine content, illustrating interrelationships with other fuel properties. The findings presented here allow rational debate on achievable vs desirable MBT-derived SRF quality, informing the development of realistic SRF quality specifications, through modeling exercises, needed for effective thermal recovery.

  9. Element composition of solid airborne particles deposited in snow in the vicinity of gas-fired heating plant

    OpenAIRE

    Talovskaya, Anna Valerievna; Yazikov, Yegor (Egor) Grigoryevich; Filimonenko, Ekaterina Anatolievna; Samokhina, Nataljya Pavlovna; Shakhova, Tatiana Sergeevna; Parygina, Irina Alekseevna

    2016-01-01

    Local heating plants are the main pollution source of rural areas. Currently, there are few studies on the composition of local heating plants emissions. The article deals with the research results of air pollution level with solid airborne particles in the vicinity of local gas-fired heating plants of some districts of Tomsk region. The snow sampling was conducted for the purpose of solid airborne particles extraction from snow cover. The content of 28 chemical elements (heavy metals, rare e...

  10. Dynamic Regime of Ignition of Solid Propellant

    Directory of Open Access Journals (Sweden)

    Zolotorev Nikolay

    2016-01-01

    Full Text Available This article presents a dynamic regime of exposure of the radiant flux on the sample of gun-cotton. Obtained time the ignition of gun-cotton in the heating conditions of increasing heat flux in the range from 0.2 W/cm2 to 22 W/cm2. A comparison of the delay times of the ignition when heated variable and constant heat flux.

  11. Parameters Affecting the Erosive Burning of Solid Rocket Motor

    Directory of Open Access Journals (Sweden)

    Abdelaziz Almostafa

    2018-01-01

    Full Text Available Increasing the velocity of gases inside solid rocket motors with low port-to-throat area ratios, leading to increased occurrence and severity of burning rate augmentation due to flow of propellant products across burning propellant surfaces (erosive burning, erosive burning of high energy composite propellant was investigated to supply rocket motor design criteria and to supplement knowledge of combustion phenomena, pressure, burning rate and high velocity of gases all of these are parameters affect on erosive burning. Investigate the phenomena of the erosive burning by using the 2’inch rocket motor and modified one. Different tests applied to fulfil all the parameters that calculated out from the experiments and by studying the pressure time curve and erosive burning phenomena.

  12. Solid waste composition analysis and recycling evaluation: Zaatari Syrian Refugees Camp, Jordan.

    Science.gov (United States)

    Saidan, Motasem N; Drais, Ammar Abu; Al-Manaseer, Ehab

    2017-03-01

    There is a need for Municipal Solid Waste (MSW) stream characterization and composition analysis to allow for an accurate estimation of its recycling potential and for effective management of the entire system. Recycling provides employment and a livelihood for vulnerable social groups such as refugees. The aim of this paper is to determine the composition of MSW in Zaatari Syrian Refugee Camp, where approximately 430,000 Syrian refugees have passed through the camp. The representative waste samples and analysis included household waste and commercial waste produced by the refugees in the selected districts in Zaatari. The waste sampling was performed in 2015 over two seasons to ensure that the seasonal fluctuations in the composition of the waste stream are taken into consideration. Hand sorting was used for classifying the collected wastes into the categories and subcategories. The organic waste represents the main waste category with 53% of the total MSW, while plastics, textile, and paper and cardboard are 12.85%, 10.22% and 9%, respectively. Moreover, the MSW composition percentage in Zaatari Camp is similar to that in municipalities in Jordan with slight disparity. The potential recyclable materials market has been investigated in this study. Plastics and paper and cardboard have significant potential to be separated and collected for recycling purposes. Financial revenues of potential recyclables have been analyzed based on local prices. Recycling model in the camp is also proposed based on the present study findings. Consequently, these results should be taken as a baseline for all Syrian refugees camps in the Middle East, as well as, in Europe. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Broad compositional tunability of indium tin oxide nanowires grown by the vapor-liquid-solid mechanism

    Directory of Open Access Journals (Sweden)

    M. Zervos

    2014-05-01

    Full Text Available Indium tin oxide nanowires were grown by the reaction of In and Sn with O2 at 800 °C via the vapor-liquid-solid mechanism on 1 nm Au/Si(001. We obtain Sn doped In2O3 nanowires having a cubic bixbyite crystal structure by using In:Sn source weight ratios > 1:9 while below this we observe the emergence of tetragonal rutile SnO2 and suppression of In2O3 permitting compositional and structural tuning from SnO2 to In2O3 which is accompanied by a blue shift of the photoluminescence spectrum and increase in carrier lifetime attributed to a higher crystal quality and Fermi level position.

  14. Analytical, 1-Dimensional Impedance Model of a Composite Solid Oxide Fuel Cell Cathode

    DEFF Research Database (Denmark)

    Mortensen, Jakob Egeberg; Søgaard, Martin; Jacobsen, Torben

    2014-01-01

    An analytical, 1-dimensional impedance model for a composite solid oxide fuel cell cathode is derived. It includes geometrical parameters of the cathode, e.g., the internal surface area and the electrode thickness, and also material parameters, e.g., the surface reaction rate and the vacancy...... diffusion coefficient. The model is successfully applied to a total of 42 impedance spectra, obtained in the temperature range 555°C–852°C and in the oxygen partial pressure range 0.028 atm–1.00 atm for a cathode consisting of a 50/50 wt% mixture of (La0.6Sr0.4)0.99CoO3 − δ and Ce0.9Gd0.1O1.95 − δ...... and providing both qualitative and quantitative information on the evolution of the impedance spectra of cathodes with changing parameters....

  15. Poly(ethylene glycol)/carbon quantum dot composite solid films exhibiting intense and tunable blue–red emission

    International Nuclear Information System (INIS)

    Hao, Yanling; Gan, Zhixing; Xu, Jiaqing; Wu, Xinglong; Chu, Paul K.

    2014-01-01

    Highlights: • Poly(ethylene glycol)/carbon quantum dots (PEG/CQDs) composite solid films exhibiting strong and tunable blue–red emission were prepared. Successful preparation of tunable emitting CQDs solid films can extend the application of carbon quantum dots in photoelectric devices. • The mechanism of the tunable emission from the PEG/CQDs composite solid films was discussed. • On the basis of the characteristics of the PL from solid films in this work, the complex PL origins of CQDs were further defined. The PL mechanism provides insights into the fluorescence mechanism of CQDs and may promotes their applications. • Poly(ethylene glycol); carbon quantum dots; Strong and tunable blue-red emission; The fluorescent quantum yield of 12.6%. - Abstract: Although carbon quantum dots (CQDs) possess excellent luminescence properties, it is a challenge to apply water-soluble CQDs to tunable luminescent devices. Herein, quaternary CQDs are incorporated into poly(ethylene glycol) to produce poly(ethylene glycol)/CQD composite solid films which exhibit strong and tunable blue–red emission. The fluorescent quantum yield reaches 12.6% which is comparable to that of many liquid CQDs and the photoluminescence characteristics are determined to elucidate the fluorescence mechanism. The CQD solid films with tunable optical properties bode well for photoelectric devices especially displays

  16. Determination of Pu isotopic composition and 241Am by high resolution gamma spectrometry on solid samples

    International Nuclear Information System (INIS)

    Sarkar, Arnab; Paul, Sumana; Aggarwal, Suresh K.; Tomar, Bhupendra S.

    2011-08-01

    The present report gives a detailed account of the development of non-destructive assay technique using high resolution gamma-ray spectrometry (HRGS) for determination of plutonium (Pu) isotopic composition and the 241 Am content in solid Pu samples. Energy range 120-420 keV was used in this study. The methodology involves in situ relative efficiency calibration during the measurement process itself, to reduce the errors and increase the reliability of the method. Twenty solid Pu samples of power reactor and research reactor grade were analyzed by this method and the results were compared with those obtained by thermal ionization mass spectrometry. The accuracy of the final results depends strongly upon the accuracy of the available nuclear data (decay constant, gamma abundance etc.). MATLAB based programme was written to perform the analysis. A counting time of 4 hour was chosen for achieving good statistics on the results for samples having 100-200 mg of Pu. The attainable accuracy is found to be 0.5-1% for the fissile isotopes ( 239 Pu + 241 Pu) and 5-10% for 241 Am content. (author)

  17. 5V-class bulk-type all-solid-state rechargeable lithium batteries with electrode-solid electrolyte composite electrodes prepared by aerosol deposition

    Science.gov (United States)

    Iriyama, Yasutoshi; Wadaguchi, Masaki; Yoshida, Koki; Yamamoto, Yuta; Motoyama, Munekazu; Yamamoto, Takayuki

    2018-05-01

    Composite electrodes (∼9 μm in thickness) composed of 5V-class electrode of LiNi0.5Mn1.5O4 (LNM) and high Li+ conductive crystalline-glass solid electrolyte (LATP, Ohara Inc.) were prepared at room temperature by aerosol deposition (AD) on platinum sheets. The resultant LNM-LATP composite electrodes were combined with LiPON and Li, and 5V-class bulk-type all-solid-state rechargeable lithium batteries (SSBs) were prepared. The crystallnity of the LNM in the LNM-LATP composite electrode was improved by annealing. Both thermogravimetry-mass spectroscopy analysis and XRD analysis clarified that the side reactions between the LNM and the LATP occurred over 500 °C with oxygen release. From these results, annealing temperature of the LNM-LATP composite electrode system was optimized at 500 °C due to the improved crystallinity of the LNM with avoiding the side-reactions. The SSBs with the composite electrodes (9 μm in thickness, 40 vol% of the LNM) annealed at 500 °C delivered 100 mAh g-1 at 10 μA cm-2 at 100 °C. Degradation of the discharge capacity with the repetition of the charge-discharge reactions was observed, which will originate from large volume change of the LNM (∼6.5%) during the reactions.

  18. The screw propeller

    Science.gov (United States)

    Larrabee, E. E.

    1980-07-01

    Marine and air screw propellers are considered in terms of theoretical hydrodynamics as developed by Joukowsky, Prandtl, and Betz. Attention is given to the flow around wings of finite span where spanwise flow exists and where lift and the bound vorticity must all go smoothly to zero at the wing tips. The concept of a trailing vortex sheet made up of infinitesimal line vortexes roughly aligned with the direction of flight is discussed in this regard. Also considered is induced velocity, which tends to convect the sheet downward at every stage in the roll-up process, the vortex theory of propellers and the Betz-Prandtl circulation distribution. The performance of the Gossamer Albatross and of a pedal-driven biplane called the Chrysalis are also discussed.

  19. Sintered glass ceramic composites from vitrified municipal solid waste bottom ashes

    International Nuclear Information System (INIS)

    Aloisi, Mirko; Karamanov, Alexander; Taglieri, Giuliana; Ferrante, Fabiola; Pelino, Mario

    2006-01-01

    A glass ceramic composite was obtained by sinter-crystallisation of vitrified municipal solid waste bottom ashes with the addition of various percentages of alumina waste. The sintering was investigated by differential dilatometry and the crystallisation of the glass particles by differential thermal analysis. The crystalline phases produced by the thermal treatment were identified by X-ray diffraction analysis. The sintering process was found to be affected by the alumina addition and inhibited by the beginning of the crystal-phase precipitation. Scanning electron microscopy was performed on the fractured sintered samples to observe the effect of the sintering. Young's modulus and the mechanical strength of the sintered glass ceramic and composites were determined at different heating rates. The application of high heating rate and the addition of alumina powder improved the mechanical properties. Compared to the sintered glass ceramic without additives, the bending strength and the Young's modulus obtained at 20 deg. C/min, increased by about 20% and 30%, respectively

  20. A New Class of Ternary Compound for Lithium-Ion Battery: from Composite to Solid Solution.

    Science.gov (United States)

    Wang, Jiali; Wu, Hailong; Cui, Yanhua; Liu, Shengzhou; Tian, Xiaoqing; Cui, Yixiu; Liu, Xiaojiang; Yang, Yin

    2018-02-14

    Searching for high-performance cathode materials is a crucial task to develop advanced lithium-ion batteries (LIBs) with high-energy densities for electrical vehicles (EVs). As a promising lithium-rich material, Li 2 MnO 3 delivers high capacity over 200 mAh g -1 but suffers from poor structural stability and electronic conductivity. Replacing Mn 4+ ions by relatively larger Sn 4+ ions is regarded as a possible strategy to improve structural stability and thus cycling performance of Li 2 MnO 3 material. However, large difference in ionic radii of Mn 4+ and Sn 4+ ions leads to phase separation of Li 2 MnO 3 and Li 2 SnO 3 during high-temperature synthesis. To prepare solid-solution phase of Li 2 MnO 3 -Li 2 SnO 3 , a buffer agent of Ru 4+ , whose ionic radius is in between that of Mn 4+ and Sn 4+ ions, is introduced to assist the formation of a single solid-solution phase. The results show that the Li 2 RuO 3 -Li 2 MnO 3 -Li 2 SnO 3 ternary system evolves from mixed composite phases into a single solid-solution phase with increasing Ru content. Meanwhile, discharge capacity of this ternary system shows significantly increase at the transformation point which is ascribed to the improvement of Li + /e - transportation kinetics and anionic redox chemistry for solid-solution phase. The role of Mn/Sn molar ratio of Li 2 RuO 3 -Li 2 MnO 3 -Li 2 SnO 3 ternary system has also been studied. It is revealed that higher Sn content benefits cycling stability of the system because Sn 4+ ions with larger sizes could partially block the migration of Mn 4+ and Ru 4+ from transition metal layer to Li layer, thus suppressing structural transformation of the system from layered-to-spinel phase. These findings may enable a new route for exploring ternary or even quaternary lithium-rich cathode materials for LIBs.

  1. Methodology to design a municipal solid waste generation and composition map: A case study

    International Nuclear Information System (INIS)

    Gallardo, A.; Carlos, M.; Peris, M.; Colomer, F.J.

    2014-01-01

    Highlights: • To draw a waste generation and composition map of a town a lot of factors must be taken into account. • The methodology proposed offers two different depending on the available data combined with geographical information systems. • The methodology has been applied to a Spanish city with success. • The methodology will be a useful tool to organize the municipal solid waste management. - Abstract: The municipal solid waste (MSW) management is an important task that local governments as well as private companies must take into account to protect human health, the environment and to preserve natural resources. To design an adequate MSW management plan the first step consist in defining the waste generation and composition patterns of the town. As these patterns depend on several socio-economic factors it is advisable to organize them previously. Moreover, the waste generation and composition patterns may vary around the town and over the time. Generally, the data are not homogeneous around the city as the number of inhabitants is not constant nor it is the economic activity. Therefore, if all the information is showed in thematic maps, the final waste management decisions can be made more efficiently. The main aim of this paper is to present a structured methodology that allows local authorities or private companies who deal with MSW to design its own MSW management plan depending on the available data. According to these data, this paper proposes two ways of action: a direct way when detailed data are available and an indirect way when there is a lack of data and it is necessary to take into account bibliographic data. In any case, the amount of information needed is considerable. This paper combines the planning methodology with the Geographic Information Systems to present the final results in thematic maps that make easier to interpret them. The proposed methodology is a previous useful tool to organize the MSW collection routes including the

  2. Solid Waste Composition Study at Taman Universiti, Parit Raja, Batu Pahat

    Science.gov (United States)

    Kadir, A. A.; Sani, M. S. A. M.

    2016-07-01

    Solid waste management is recognised as one of the most challenging issues confronted by both the developed and developing countries. The problems rise due to growing population in current years which results in increased generation of waste with various compositions. The aim of this study was to determine the waste compositions at Taman Universiti. Taman Universiti is a mix residential and commercial area which a preferred residential location amongst students and lecturers due to its proximate location to UTHM main campus. The waste collection was carried out for 50 houses on a daily basis. The collection and sorting out method was conducted according to Malaysian Standard MS 2505:2012 and the data was collected and recorded The result showed that the average generation rate of household waste at Taman Universiti was 0.16kg/person/day and the moisture content was approximately ranging from 61%-68%. Household wastes collected were categorized and it consisted of food and organic, paper, rigid plastics, plastics film, baby diapers, glass, tetra pak, household hazardous waste, metal, rubber, textiles, garden waste and leather. The proportion of each wastes were approximately 64.67%, 9.36%, 9.22%, 5.33%, 3.51%, 2.53%, 1.37%, 1.05%, 0.84%, 0.85%, 0.80%, 0.27%, and 0.23%, respectively. Results from the analyses indicated that the food and organic waste are the major composition of household waste at Taman Universiti followed by the paper, rigid plastics, and plastic film. Meanwhile, the proportion of baby diapers, glass, tetra pak, household hazardous waste, metal, rubber, textiles, and garden decreasing accordingly. In addition, leather was recognized as the least category that contributed to the household waste.

  3. Interface analysis of A1 matrix composites produced by hot isostatic pressing, squeeze casting and semi-solid processing

    International Nuclear Information System (INIS)

    Shamsul, J.B.; Zainal Arifin Ahmad; Faaizulaswad, M.S.; Azmi, R.

    2000-01-01

    The interface analysis has been carried out an aluminium based composites system produced by hot isostatic pressing, squeeze casting and semi-solid processing. A range of different fabrication techniques has been used to produce different types of microstructure of Al 2124 (Al-Cu-Mg) reinforced with 5 weight % SiC particles. Blending followed by hot isostatic pressing is used to fabricate composite I. Composite II was 6061 (Al-Si-Mg) wrought aluminium alloy reinforced with fibres of alumina-silica (V f = 0.58) and fabricated by squeeze casting. Finally, A356 (AlSi7Mg0.3) alloy was reinforced with 20 Vol.% of SiC particles (13 μm) and namely as composite III. Composite III is fabricated by semi-solid processing. Interface analysis was done by optical microscopy, scanning and transmission electron microscopy. Composite I exhibited good interface bonding and dislocation was also observed near the interface. Elements such as Al, Fe, Cr, Mn were found near the interface of composite II and intermetallic of iron rich inclusion and Mg 2 Si were observed near the interface of composite III. (Author)

  4. Predictive Local Composition Models for Solid/Liquid Equilibrium in n-Alkane Systems: Wilson Equation for Multicomponent Systems

    DEFF Research Database (Denmark)

    Coutinho, João A.P.; Stenby, Erling Halfdan

    1996-01-01

    The predictive local composition model is applied to multicomponent hydrocarbon systems with long-chain n-alkanes as solutes. The results show that it can successfully be extended to highorder systems and accurately predict the solid appearance temperature, also known as cloud point, in solutions...

  5. Oxidation behaviour and electrical properties of cobalt/cerium oxide composite coatings for solid oxide fuel cell interconnects

    DEFF Research Database (Denmark)

    Harthøj, Anders; Holt, Tobias; Møller, Per

    2015-01-01

    This work evaluates the performance of cobalt/cerium oxide (Co/CeO2) composite coatings and pure Co coatings to be used for solid oxide fuel cell (SOFC) interconnects. The coatings are electroplated on the ferritic stainless steels Crofer 22 APU and Crofer 22H. Coated and uncoated samples...

  6. Effects of early rumen development and solid feed composition on growth performance and abomasal health in veal calves.

    NARCIS (Netherlands)

    Berends, H.; Reenen, van C.G.; Stockhofe, N.; Gerrits, W.J.J.

    2012-01-01

    The experiment was designed to study the importance of early rumen development and of the composition of solid feed intake on growth performance and abomasal health in milk-fed veal calves. One hundred and six Holstein-Friesian male calves were included in the experiment, and studied during 2

  7. New pbysical methods used in the study of composition, electronic properties and surface phenomena of solid substances. I. Electronic spectroscopies

    International Nuclear Information System (INIS)

    Toderean, A; Ilonca, Gh.

    1981-01-01

    The discovery of different kinds of interactions between solids and fotonic, respectively electronic and ionic beams, leads to the development of many new, very sensitive, physical methods for the study of solids. This monograph tries to present some of these methods, useful in compositional analysis, in the study of electronic properties and of the surface processes of solid substances. This is done from the point of view both of physical phenomena underlying them and of the information obtainable with such methods. But the whole monograph is limited only to the methods based on the electronic properties of the elements existing in the solid probes studied and this paper presents only those of them in which the detected beam is an electronic one, like: ELS, DAPS, ILS, AES, AEAPS, INS, TSS, XPS and UPS. (authors)

  8. Applications and Properties of Ionic Liquid- Based Gels and Soft Solid Composites

    Science.gov (United States)

    Voss, Bret Alan McGinness

    2011-12-01

    Solid-liquid composites (gels) have a combination of properties that afford new material applications in which high solute diffusion is desirable. These composites have a soft-solid mechanical integrity and will not flow under gravity, but entrain a liquid matrix (i.e. 60-98 mass %) which allows for high diffusion and high reactivity. Room temperature ionic liquid (RTILs) are molten organic salts with a melting point below room temperature and negligible vapor pressure. If the RTILs are used as the liquid component of a gel, then the gel matrix will not evaporate (unlike other organic solvents) and may be used for long term applications. This thesis research applies RTIL gels for two new applications; carbon dioxide/nitrogen separation and chemical warfare agent (CWA) barrier and decontamination. Separating CO2 from the flue gas of coal and gas fired power-plants is an increasingly economically and environmentally important gas separation. In this first study, RTIL gels are cast in a supported membrane and gas permeability and ideal selectivity are measured. The RTIL matrix has an inherent affinity for CO2 and provides a high diffusion, hence high permeability (i.e. 500-700 barrer). The solidifying component is a low molecular-weight organic gelator (LMOG) which through physical bonding interactions (i.e. hydrogen bonding, pi-pi stacking and van der Walls forces) forms an entangled network which provides mechanical stability (i.e. increase trans-membrane pressure required to expel selective material from the support). In these studies two LMOGs and five RTILs are used to make supported gel membranes and determine gas permeability and temperature dependent trends. The second application for RTIL gels is a decontaminating barrier for CWAs and toxic industrial compounds (TICs). In these studies a layer of RTIL gel is applied on top of a substrate contaminated with a CWA simulant (i.e. chloroethylethylsulfide, CEES). The gel performs well as a barrier, preventing CEES

  9. Small transport aircraft technology propeller study

    Science.gov (United States)

    Black, B. M.; Magliozzi, B.; Rohrbach, C.

    1983-01-01

    A study to define potential benefits of advanced technology propeller for 1985-1990 STAT commuter airplanes was completed. Two baselines, a Convair, 30 passenger, 0.47 Mach number airplane and a Lockheed, 50 passenger, 0.70 Mach number airplane, were selected from NASA-Ames sponsored airframe contracts. Parametric performance, noise level, weight and cost trends for propellers with varying number of blades, activity factor, camber and diameter incorporating blade sweep, tip proplets, advanced composite materials, advanced airfoils, advanced prevision synchrophasing and counter-rotation are presented. The resulting DOC, fuel burned, empty weight and acquisition cost benefits are presented for resizings of the two baseline airplanes. Six-bladed propeller having advanced composite blades, advanced airfoils, tip proplets and advanced prevision synchrophasers provided the maximum DOC improvements for both airplanes. DOC and fuel burned were reduced by 8.3% and 17.0% respectively for the Convair airplane and by 24.9% and 41.2% respectively for the Lockheed airplane. The larger reductions arose from a baseline definition with very heavy fuselage acoustic treatment. An alternate baseline, with a cabin noise 13dB in excess of the objective, was also studied.

  10. Mathematical modeling of current density distribution in composite cathode of solid oxide fuel cells. Paper no. IGEC-1-099

    International Nuclear Information System (INIS)

    Kenney, B.; Karan, K.

    2005-01-01

    Cathodes processes in a solid oxide fuel cell (SOFC) are thought to dominate the overall electrochemical losses. One strategy for minimizing the cathode electrochemical losses in a state-of-the-art SOFC that utilize lanthanum-strontium-manganate (LSM) electrocatalyst and yttria-stabilized-zirconia (YSZ) electrolyte is to utilize composite cathodes comprising a mixture of LSM and YSZ. Composite cathodes improve performance by extending the active reaction zone from electrolyte-electrode interface to throughout the electrode. In this study, a two-dimensional composite cathode model was developed to assess cathode performance in terms of current density distributions. The model results indicate that geometric and microstructural parameters strongly influence current density distribution. In addition electrode composition affects magnitude and distribution of current. An optimum composition for equal-sized LSM/YSZ is 40 vol% LSM and 60 vol% YSZ at 900 o C. (author)

  11. Strength of Screw Propellers

    Science.gov (United States)

    1975-07-07

    ship because of increese of propeller efficiency and saving on the high cost of difficult to obtain materials (bronze, brass, stainless steel). The...indAjate that. x :axmuin stresses in the blade cross section are the cor-,prc-.,; ivFe norm-al strcs3es at point G. The maximom tensile stres-ses cis a...and stern part of the ship. Because of purely technical difficulties and also because of the relatively high cost of preparations for such tests, only

  12. Formation of solid materials in the preplanetary nebula and the composition of chondrites

    Energy Technology Data Exchange (ETDEWEB)

    Izakov, M.N.

    1986-07-01

    On the basis of the model of the formation of the preplanetary nebula as an accretion disk during the formation of the sun, the hypothesis is proposed that a significant fraction of the solid materials of the preplanetary nebula was formed by the successive condensation of the components of the gas of solar composition during its motion from the hot, dense region near the protosun to the periphery of the nebula into regions of ever decreasing values of temperature and pressure. The hypothesis removes the contradiction materials and the presence of traces of high-temperature phenomena in chondrite materials and the conclusion that there were never high temperature in the preplanetary nebula at distances of 2-4 AU from the sun, where meteorites encountering the earth originate, and also explains a number of properties of chondrites. It follows from this hypothesis that the mass and angular momentum of the nebula were close to their minimum possible values and that the loss of the nebular gas had already begun at the final stage of its formation.

  13. Formation of solid materials in the preplanetary nebula and the composition of chondrites

    International Nuclear Information System (INIS)

    Izakov, M.N.

    1986-01-01

    On the basis of the model of the formation of the preplanetary nebula as an accretion disk during the formation of the sun, the hypothesis is proposed that a significant fraction of the solid materials of the preplanetary nebula was formed by the successive condensation of the components of the gas of solar composition during its motion from the hot, dense region near the protosun to the periphery of the nebula into regions of ever decreasing values of temperature and pressure. The hypothesis removes the contradiction materials and the presence of traces of high-temperature phenomena in chondrite materials and the conclusion that there were never high temperature in the preplanetary nebula at distances of 2-4 AU from the sun, where meteorites encountering the earth originate, and also explains a number of properties of chondrites. It follows from this hypothesis that the mass and angular momentum of the nebula were close to their minimum possible values and that the loss of the nebular gas had already begun at the final stage of its formation

  14. Electrolytic Production of Ti5Si3/TiC Composites by Solid Oxide Membrane Technology

    Science.gov (United States)

    Zheng, Kai; Zou, Xingli; Xie, Xueliang; Lu, Changyuan; Chen, Chaoyi; Xu, Qian; Lu, Xionggang

    2018-02-01

    This paper investigated the electrolytic production of Ti5Si3/TiC composites from TiO2/SiO2/C in molten CaCl2. The solid-oxide oxygen-ion-conducting membrane tube filled with carbon-saturated liquid tin was served as the anode, and the pressed spherical TiO2/SiO2/C pellet was used as the cathode. The electrochemical reduction process was carried out at 1273 K and 3.8 V. The characteristics of the obtained cathode products and the reaction mechanism of the electroreduction process were studied by a series of time-dependent electroreduction experiments. It was found that the electroreduction process generally proceeds through the following steps: TiO2/SiO2/C → Ti2O3, CaTiO3, Ca2SiO4, SiC → Ti5Si3, TiC. The morphology observation and the elemental distribution analysis indicate that the reaction routes for Ti5Si3 and TiC products are independent during the electroreduction process.

  15. Volatile composition of peppermint (Mentha piperita L.) commercial teas through solid phase extraction.

    Science.gov (United States)

    Riachi, L G; Abi-Zaid, I E; Moreira, R F A; De Maria, C A B

    2012-12-01

    Volatiles from aqueous extract of peppermint commercial sachets were investigated through gas chromatography/flame ionization detection (GC/FID) and GC/mass spectrometry (MS). Samples were prepared under similar conditions as in homemade tea. Volatiles were isolated using solid phase extraction method (SPE) with Porapak Q trap followed by desorption with acetone. Estimated mean values for short and medium chain carboxylic acids (C2-C12) and ketones lay in the range of 50-64 microg kg(-1) whilst aliphatic alcohols and acyclic hydrocarbons had values lower than 6 microg kg(-1). The major volatiles were terpenes (275-382 microg kg(-1)) that reached 89 % of the total composition. A total of 16 compounds, among them dodecane, acetoin, acetol, citral, geraniol and octanoic acid have been described by the first time in peppermint tea. These findings could be attributed to the different analytical approach employed, mainly to the use of different extraction/pre-concentration techniques. Given the apparently lower proportion of terpenes in the aqueous extract it may be that the chemical properties of the peppermint essential oil are not entirely reproduced with homemade tea.

  16. Three-dimensional random resistor-network model for solid oxide fuel cell composite electrodes

    International Nuclear Information System (INIS)

    Abbaspour, Ali; Luo Jingli; Nandakumar, K.

    2010-01-01

    A three-dimensional reconstruction of solid oxide fuel cell (SOFC) composite electrodes was developed to evaluate the performance and further investigate the effect of microstructure on the performance of SOFC electrodes. Porosity of the electrode is controlled by adding pore former particles (spheres) to the electrode and ignoring them in analysis step. To enhance connectivity between particles and increase the length of triple-phase boundary (TPB), sintering process is mimicked by enlarging particles to certain degree after settling them inside the packing. Geometrical characteristics such as length of TBP and active contact area as well as porosity can easily be calculated using the current model. Electrochemical process is simulated using resistor-network model and complete Butler-Volmer equation is used to deal with charge transfer process on TBP. The model shows that TPBs are not uniformly distributed across the electrode and location of TPBs as well as amount of electrochemical reaction is not uniform. Effects of electrode thickness, particle size ratio, electron and ion conductor conductivities and rate of electrochemical reaction on overall electrochemical performance of electrode are investigated.

  17. Space Shuttle solid rocket booster

    Science.gov (United States)

    Hardy, G. B.

    1979-01-01

    Details of the design, operation, testing and recovery procedures of the reusable solid rocket boosters (SRB) are given. Using a composite PBAN propellant, they will provide the primary thrust (six million pounds maximum at 20 s after ignition) within a 3 g acceleration constraint, as well as thrust vector control for the Space Shuttle. The drogues were tested to a load of 305,000 pounds, and the main parachutes to 205,000. Insulation in the solid rocket motor (SRM) will be provided by asbestos-silica dioxide filled acrylonitrile butadiene rubber ('asbestos filled NBR') except in high erosion areas (principally in the aft dome), where a carbon-filled ethylene propylene diene monomer-neopreme rubber will be utilized. Furthermore, twenty uses for the SRM nozzle will be allowed by its ablative materials, which are principally carbon cloth and silica cloth phenolics.

  18. HIGH ENERGY REPLACEMENT FOR TEFLON PROPELLANT IN PULSED PLASMA THRUSTERS, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This program will utilize a well-characterized Pulsed Plasma Thruster (PPT) to test experimental high-energy extinguishable solid propellants (HE), instead of...

  19. Chemically and compositionally modified solid solution disordered multiphase nickel hydroxide positive electrode for alkaline rechargeable electrochemical cells

    Science.gov (United States)

    Ovshinsky, Stanford R.; Corrigan, Dennis; Venkatesan, Srini; Young, Rosa; Fierro, Christian; Fetcenko, Michael A.

    1994-01-01

    A high capacity, long cycle life positive electrode for use in an alkaline rechargeable electrochemical cell comprising: a solid solution nickel hydroxide material having a multiphase structure that comprises at least one polycrystalline .gamma.-phase including a polycrystalline .gamma.-phase unit cell comprising spacedly disposed plates with at least one chemical modifier incorporated around the plates, the plates having a range of stable intersheet distances corresponding to a 2.sup.+ oxidation state and a 3.5.sup.+, or greater, oxidation state; and at least one compositional modifier incorporated into the solid solution nickel hydroxide material to promote the multiphase structure.

  20. ZnO nanorod array polydimethylsiloxane composite solid phase micro-extraction fiber coating: fabrication and extraction capability.

    Science.gov (United States)

    Wang, Dan; Wang, Qingtang; Zhang, Zhuomin; Chen, Guonan

    2012-01-21

    ZnO nanorod array coating is a novel kind of solid-phase microextraction (SPME) fiber coating which shows good extraction capability due to the nanostructure. To prepare the composite coating is a good way to improve the extraction capability. In this paper, the ZnO nanorod array polydimethylsiloxane (PDMS) composite SPME fiber coating has been prepared and its extraction capability for volatile organic compounds (VOCs) has been studied by headspace sampling the typical volatile mixed standard solution of benzene, toluene, ethylbenzene and xylene (BTEX). Improved detection limit and good linear ranges have been achieved for this composite SPME fiber coating. Also, it is found that the composite SPME fiber coating shows good extraction selectivity to the VOCs with alkane radicals.

  1. Development of a portable mass spectrometric system for determination of isotopic composition of solid uranium samples using fluorine volatilization

    Science.gov (United States)

    Loge, G.

    1994-09-01

    Using hardware and materials supplied by LANL, a prototype quadrupole mass spectrometer system designed for portable field analysis of isotopic composition of solid uranium samples was assembled and tested. The system contained the capability for fluorine volatilization of solid uranium samples with gas introduction, which was successfully tested and demonstrated using 100 mg samples of U3O8. Determination of precision and accuracy for measuring isotopic composition was performed using isotopic standards. Use with soil samples containing uranium were also attempted. Silicates in the soil forming SiF4 were found to be a kinetic bottleneck to the formation of UF6. This could be avoided by performing some sort of chemical separation as a pre-treatment step, which was demonstrated using nitric acid.

  2. IVABRADINE LOADED SOLID LIPID MICROPARTICLES: FORMULATION, CHARACTERIZATION AND OPTIMIZATION BY CENTRAL COMPOSITE ROTATABLE DESIGN.

    Science.gov (United States)

    Hanif, Muhammad; Khan, Hafeez Ullah; Afzal, Samina; Sher, Muhammad

    2017-01-01

    The current research focused on improvement of oral bioavailability and decrease in dosing frequency of ivabradine (Iva) in order to enhance patient compliance by formulating novel sustained release Iva loaded solid lipid microparticles (SLMs) with the help of melt emulsification technique. SLMs formulations were designed with the help of three level central composite rotatable design (CCRD) to study the impact of independent variables like lipid concentration, surfactant concentration and stirring speed on responses - percentage yield (Y,) and entrapment efficiency (Y2). Compatibility between the drug and bees wax (BW) was checked by conducting Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRD). SLMs were further evaluated for rheological behavior, zeta potential, particle size and for morphology by scanning'electron microscope (SEM). The release of drug from SLMs was conducted by USP type-Il apparatus at pH 1.2, pH 6.8 and data were analyzed by different kinetic models like zero order, first order, Higuchi model, Korsmeyer-Peppas and Hixon-Crowell models. The rheo- logical studies approved the good flow behavior of SLMs and spherical smooth surface of SLMs was observed from SEM. DSC, FTIR and XRD studies concluded the lack of any possible interaction between formulation components. The size-of SLMs ranged from 300 to 500 pm and zeta potential study showed the presence of higher negative charge (-30 to -52 mV). Response Y, varied from 53 to 90% and response Y2 ranged from 29 to 78% indicating the effect of formulation variables. The obtained outcomes were analyzed by second order polynomial equation and suggested quadratic model was also validated. SLMs released Iva from 54 to 90% at pH 6.8 and was significantly (p 0.05) affected by BW concentration. The release mechanism followed the zero order and Korsmeyer-Peppas (n 0.85) kinetic models suggesting slow erosion along with diffusion

  3. Morphology, composition, and mixing state of primary particles from combustion sources ? crop residue, wood, and solid waste

    OpenAIRE

    Liu, Lei; Kong, Shaofei; Zhang, Yinxiao; Wang, Yuanyuan; Xu, Liang; Yan, Qin; Lingaswamy, A. P.; Shi, Zongbo; Lv, Senlin; Niu, Hongya; Shao, Longyi; Hu, Min; Zhang, Daizhou; Chen, Jianmin; Zhang, Xiaoye

    2017-01-01

    Morphology, composition, and mixing state of individual particles emitted from crop residue, wood, and solid waste combustion in a residential stove were analyzed using transmission electron microscopy (TEM). Our study showed that particles from crop residue and apple wood combustion were mainly organic matter (OM) in smoldering phase, whereas soot-OM internally mixed with K in flaming phase. Wild grass combustion in flaming phase released some Cl-rich-OM/soot particles and cardboard combusti...

  4. Effect of the addition of sugar cane bagasse fibers in the composite with the copolymer vinyl ethylene-acetate (EVA) by solid state NMR

    International Nuclear Information System (INIS)

    Stael, Giovanni Chaves; D'Almeida, Jose Roberto Moraes; Menezes, Sonia M.C. de; Tavares, Maria Ines Bruno

    1997-01-01

    Natural fibers composites obtained form sugar cane bagasse and ethylene-vinyl-acetate copolymer were prepared with different compositions and analysed by solid state Carbon-13 NMR aiming the observation of molecular mobility, compatibility, and chemical structure of the different obtained composites. One objective of this work was to enable the future commercial application of these materials

  5. Effect of composition in the development of carbamazepine hot-melt extruded solid dispersions by application of mixture experimental design.

    Science.gov (United States)

    Djuris, Jelena; Ioannis, Nikolakakis; Ibric, Svetlana; Djuric, Zorica; Kachrimanis, Kyriakos

    2014-02-01

    This study investigates the application of hot-melt extrusion for the formulation of carbamazepine (CBZ) solid dispersions, using polyethyleneglycol-polyvinyl caprolactam-polyvinyl acetate grafted copolymer (Soluplus, BASF, Germany) and polyoxyethylene-polyoxypropylene block copolymer (Poloxamer 407). In agreement with the current Quality by Design principle, formulations of solid dispersions were prepared according to a D-optimal mixture experimental design, and the influence of formulation composition on the properties of the dispersions (CBZ heat of fusion and release rate) was estimated. Prepared solid dispersions were characterized using differential scanning calorimetry, attenuated total reflectance infrared spectroscopy and hot stage microscopy, as well as by determination of the dissolution rate of CBZ from the hot-melt extrudates. Solid dispersions of CBZ can be successfully prepared using the novel copolymer Soluplus. Inclusion of Poloxamer 407 as a plasticizer facilitated the processing and decreased the hardness of hot-melt extrudates. Regardless of their composition, all hot-melt extrudates displayed an improvement in the release rate compared to the pure CBZ, with formulations having the ratio of CBZ : Poloxamer 407 = 1 : 1 showing the highest increase in CBZ release rate. Interactions between the mixture components (CBZ and polymers), or quadratic effects of the components, play a significant role in overall influence on the CBZ release rate. © 2013 Royal Pharmaceutical Society.

  6. Controlling the alloy composition of PtNi nanocrystals using solid-state dewetting of bilayer films

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Okkyun; Oh, Se An; Lee, Ji Yeon; Ha, Sung Soo; Kim, Jae Myung; Choi, Jung Won; Kim, Jin-Woo [Department of Physics and Photon Science & School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005 (Korea, Republic of); Kang, Hyon Chol [Department of Materials and Science Engineering, Chosun University, Gwangju 61542 (Korea, Republic of); Noh, Do Young, E-mail: dynoh@gist.ac.kr [Department of Physics and Photon Science & School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005 (Korea, Republic of)

    2016-05-15

    We demonstrate that solid-state dewetting of bilayer films is an effective way for obtaining bimetallic alloy nanocrystals of controlled composition. When a Pt–Ni bilayer film were annealed near 700 °C, Pt and Ni atoms inter-diffused to form a PtNi bimetallic alloy film. Upon annealing at higher temperatures, the bilayer films transformed into <111> oriented PtNi alloy nanocrystals in small-rhombicuboctahedron shape through solid-state dewetting process. The Pt content of the nanocrystals and the alloy films, estimated by applying the Vegard's law to the relaxed lattice constant, was closely related to the thickness of each layer in the as-grown bilayer films which can be readily controlled during bilayer deposition. - Highlights: • Composition control of PtNi nanoparticles using solid state dewetting is proposed. • PtNi alloy composition was controlled by thickness ratio of Pt–Ni bilayer films. • PtNi alloy nanocrystals were obtained in small-rhombicuboctahedron shape.

  7. All-solid-state flexible microsupercapacitors based on reduced graphene oxide/multi-walled carbon nanotube composite electrodes

    Science.gov (United States)

    Mao, Xiling; Xu, Jianhua; He, Xin; Yang, Wenyao; Yang, Yajie; Xu, Lu; Zhao, Yuetao; Zhou, Yujiu

    2018-03-01

    All-solid-state flexible microsupercapacitors have been intensely investigated in order to meet the rapidly growing demands for portable microelectronic devices. Herein, we demonstrate a facile, readily scalable and cost-effective laser induction process for preparing reduced graphene oxide/multi-walled carbon nanotube composite, which can be used as the interdigital electrodes in microsupercapacitors. The obtained composite exhibits high volumetric capacitance about 49.35 F cm-3, which is nearly 5 times higher than that of the pristine reduced graphene oxide film in aqueous 1.0 M H2SO4 solution (measured at a current density of 5 A cm-3 in a three-electrode testing). Additionally, an all-solid-state flexible microsupercapacitor employing these composite electrodes with PVA/H3PO4 gel electrolyte delivers high volumetric energy density of 6.47 mWh cm-3 at 10 mW cm-3 under the current density of 20 mA cm-3 as well as achieve excellent cycling stability retaining 88.6% of its initial value and outstanding coulombic efficiency after 10,000 cycles. Furthermore, the microsupercapacitors array connected in series/parallel can be easily adjusted to achieve the demands in practical applications. Therefore, this work brings a promising new candidate of prepare technologies for all-solid-state flexible microsupercapacitors as miniaturized power sources used in the portable and wearable electronics.

  8. Towards the improvement of the oxidation resistance of Nb-silicides in situ composites: A solid state diffusion approach

    International Nuclear Information System (INIS)

    Mathieu, S.; Knittel, S.; François, M.; Portebois, L.; Mathieu, S.; Vilasi, M.

    2014-01-01

    Highlights: •Local equilibrium is attained during oxidation at phase boundaries (steady state conditions). •A solid state diffusion model explains the oxidation mechanism of Nb-silicides composites. •The Nb ss fraction is not the only parameters governing the oxidation rate of Nb-silicides. •Aluminium increases the thermodynamic activity of Si in the Nb-silicides composites. •The results indicate the need to develop a Nb–Ti–Hf–Al–Cr–Si thermodynamic database. -- Abstract: The present study focuses on the oxidation mechanism of Nb-silicide composites and on the effect of the composition on the oxidation rate at 1100 °C. A theoretical approach is proposed based on experimental results and used to optimise the oxidation resistance. The growth model based on multiphase diffusion was experimentally tested and confirmed by manufacturing seven composites with different compositions. It was also found that the effect of the composition has to be evaluated at 1100 °C within a short time duration (50 h), where the oxide scale and the internal oxidation zone both grow according to parabolic kinetics

  9. Flexible all-solid-state high-performance supercapacitor based on electrochemically synthesized carbon quantum dots/polypyrrole composite electrode

    International Nuclear Information System (INIS)

    Jian, Xuan; Yang, Hui-min; Li, Jia-gang; Zhang, Er-hui; Cao, Le-le; Liang, Zhen-hai

    2017-01-01

    Highlights: • Porous nanostructure carbon quantum dots/polypyrrole composite film was successfully synthesized by direct electrochemical method. • A flexible all-solid-state supercapacitor device was fabricated using the carbon quantum dots/polypyrrole composite electrode. • The flexible supercapacitor exhibits high specific capacitance, excellent reliability and long cycling life. - Abstract: Recently, carbon quantum dots (CQDs) as a new zero-dimensional carbon nanomaterial have become a focus in electrochemical energy storage. In this paper, flexible all-solid-state supercapacitors (ASSSs) were electrochemically synthesized by on-step co-deposition of appropriate amounts of pyrrole monomer and CQDs in aqueous solution. The different electrodeposition time plays an important role in controlling morphologies of stainless steel wire meshes (SSWM)-supported CQDs/PPy composite film. The morphologies and compositions of the obtained CQDs/PPy composite electrodes were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectrum and X-ray photoelectron spectroscopy (XPS). Furthermore, a novel flexible ASSS device was fabricated using CQDs/PPy composite as the electrode and separated by polyvinyl alcohol/LiCl gel electrolyte. Benefiting from superior electrochemical properties of CQDs and PPy, the as-prepared CQDs/PPy composite ASSSs exhibit outstanding electrochemical performance with the areal capacitance 315 mF cm −2 (corresponding to specific capacitance of 308 F g −1 ) at a current density of 0.2 mA cm −2 and long cycle life with 85.7% capacitance retention after 2 000 cycles.

  10. Hull-Propeller Interaction and Its Effect on Propeller Cavitation

    DEFF Research Database (Denmark)

    Regener, Pelle Bo

    In order to predict the required propulsion power for a ship reliably and accurately, it is not sufficient to only evaluate the resistance of the hull and the propeller performance in open water alone. Interaction effects between hull and propeller can even be a decisive factor in ship powering...... prediction and design optimization. The hull-propeller interaction coefficients of effective wake fraction, thrust deduction factor, and relative rotative efficiency are traditionally determined by model tests. Self-propulsion model tests consistently show an increase in effective wake fractions when using...... velocities. This offers an opportunity for additional insight into hull-propeller interaction and the propeller’s actual operating condition behind the ship, as the actual (effective) inflow is computed. Self-propulsion simulations at model and full scale were carried out for a bulk carrier, once...

  11. Mechanical and Thermal Properties of Dental Composites Cured with CAD/CAM Assisted Solid-State Laser

    Directory of Open Access Journals (Sweden)

    Roberto De Santis

    2018-03-01

    Full Text Available Over the last three decades, it has been frequently reported that the properties of dental restorative composites cured with argon laser are similar or superior to those achieved with conventional halogen and light emitting diode (LED curing units. Whereas laser curing is not dependent on the distance between the curing unit and the material, such distance represents a drawback for conventional curing units. However, a widespread clinical application of this kind of laser remains difficult due to cost, heavy weight, and bulky size. Recently, with regard to the radiation in the blue region of the spectrum, powerful solid-state lasers have been commercialized. In the current research, CAD (computer-aided design/CAM (computer-aided manufacturing assisted solid-state lasers were employed for curing of different dental restorative composites consisting of micro- and nanoparticle-reinforced materials based on acrylic resins. Commercial LED curing units were used as a control. Temperature rise during the photopolymerisation process and bending properties were measured. By providing similar light energy dose, no significant difference in temperature rise was observed when the two light sources provided similar intensity. In addition, after 7 days since curing, bending properties of composites cured with laser and LED were similar. The results suggested that this kind of laser would be suitable for curing dental composites, and the curing process does not suffer from the tip-to-tooth distance.

  12. Mechanical and Thermal Properties of Dental Composites Cured with CAD/CAM Assisted Solid-State Laser

    Science.gov (United States)

    De Santis, Roberto; Gloria, Antonio; Maietta, Saverio; Martorelli, Massimo; De Luca, Alessandro; Spagnuolo, Gianrico; Riccitiello, Francesco; Rengo, Sandro

    2018-01-01

    Over the last three decades, it has been frequently reported that the properties of dental restorative composites cured with argon laser are similar or superior to those achieved with conventional halogen and light emitting diode (LED) curing units. Whereas laser curing is not dependent on the distance between the curing unit and the material, such distance represents a drawback for conventional curing units. However, a widespread clinical application of this kind of laser remains difficult due to cost, heavy weight, and bulky size. Recently, with regard to the radiation in the blue region of the spectrum, powerful solid-state lasers have been commercialized. In the current research, CAD (computer-aided design)/CAM (computer-aided manufacturing) assisted solid-state lasers were employed for curing of different dental restorative composites consisting of micro- and nanoparticle-reinforced materials based on acrylic resins. Commercial LED curing units were used as a control. Temperature rise during the photopolymerisation process and bending properties were measured. By providing similar light energy dose, no significant difference in temperature rise was observed when the two light sources provided similar intensity. In addition, after 7 days since curing, bending properties of composites cured with laser and LED were similar. The results suggested that this kind of laser would be suitable for curing dental composites, and the curing process does not suffer from the tip-to-tooth distance. PMID:29584683

  13. An advanced GAP/AN/TAGN propellant : part 2 : stability and storage life

    Energy Technology Data Exchange (ETDEWEB)

    Judge, M.D. [Bristol Aerospace, Winnipeg, MB (Canada); Badeen, C.M.; Jones, D.E.G. [Natural Resources Canada, Ottawa, ON (Canada). Canadian Explosives Research Laboratory

    2007-07-15

    An advanced solid propellant was characterized. The propellant was based on a glycidyl azide polymer (GAP) energetic binder with an ammonium nitrate (AN) oxidizer, and contained a significant percentage of triaminoguanidine nitrate (TAGN). Raw ingredient accelerating rate calorimetry (ARC) was performed to determine self-heating rates. Thermal stability and heat flow calorimetry tests were also conducted. Ballistic analyses were conducted to determine the propellant's burn rate. The propellant was designed to produce non-toxic and non-acidic exhaust products. Results of the tests indicated that the propellant is safe for prolonged storage. The study demonstrated that propellant samples can be heated to temperatures up to 175 degrees C for several hours without combustion response. A mass loss of 62 per cent was observed at temperatures between 160 and 230 degrees C. The samples ignited almost immediately after being placed in a pre-heated block at temperatures higher than 175 degrees C. The propellant's burn rate was approximately twice that of standard AN propellants. The propellant will be further evaluated as a candidate for the propulsion of tactical rockets and missiles. 17 refs., 4 tabs., 6 figs.

  14. Household solid waste generation rate and physical composition analysis: case of Sekondi-Takoradi Metropolis in the western region, Ghana

    Directory of Open Access Journals (Sweden)

    Eugene Atta Nyankson

    2015-06-01

    Full Text Available Sekondi-Takoradi Metropolis, one of the rapidly expanding cities of Ghana has been facing serious problems with solid waste management. This is mainly due to the lack of available information about the types and quantity of solid waste generation in the area. Hence, the objective of this study was to determine the rate of household solid waste generation and its composition in the aforesaid city. The methodology and procedures for this study were derived from the Standard Test Method for Determination of the Composition of Unprocessed MSW (ASTM D 5231-92. All samples were hand sorted into 6 waste categories (paper, plastic, organics, metals, glass, and other waste. The study revealed that by weight, organic wastes constitutes the largest proportion of household solid waste (38% followed by 19% plastics, 7% papers, 4% metals, 4% glass and 28% other wastes (comprising of sand, stones, ash, inert substances. The rate of daily waste generation per capita in the low, middle and high income households were 0.27±0.19, 0.4±0.19 and 0.58±0.24 kg/cap/day, respectively. The study revealed that there is no waste treatment or recovery facility established within the metropolis hence no significant waste recovery and reuse activities exist. The study showed that more than 38 % of the waste generated in Sekondi-Takoradi Metropolis is decomposable organic matter that can be re-used through composting as well as 34% of the waste having recycling potential thereby considerably mitigating the solid waste problem. DOI: http://dx.doi.org/10.3126/ije.v4i2.12644 International Journal of Environment Vol.4(2 2015: 221-235

  15. Comparative study of municipal solid waste generation and composition in Shiraz city (2014

    Directory of Open Access Journals (Sweden)

    A. Norouzian Baghani

    2017-06-01

    Full Text Available Background: Exponential growths of population and urbanization, and the development of social economy have resulted in an increase in the amount of MSW generation throughout the world. Objective: The present study aimed to survey qualitative and quantitative analysis of solid waste in Shiraz city and comparative these results with the world scenario of solid wastes generation for improving the sustainable management of solid waste. Methods: This cross-sectional study was conducted in 2014 in nine municipality regions Shiraz with a total population of approximately 1,549,354 people. Basic data was gathered through Shiraz waste management organization. Then generation (per capita and constituent percent of the solid waste were evaluated based on the sampling and field analyzing from reliable guidelines. Data were analyzed with Stata-13 and Excel statistical software. Kolmogorov-Smirnov test used for the normality of variables. Means were compared by Student T test and Mann-Whitney test. Findings: The rate of solid waste generated in the Shiraz city was 222.65 kg per person per year in 2014. Statistical analysis showed that the variables of organic materials, paper and cardboard, glass and metal between developed and developing countries were a significant difference (P0.05. Conclusion: Solid waste per capita in Shiraz city (about 600 g/day was near to the average amount of solid waste generation in Iran and other developing countries. Due to the high content of organic material in municipal solid waste of Shiraz, minimization of these material and separation of dry and wet solid wastes must be noted from the people and municipalities.

  16. Diagnostics of Gun Barrel Propellants

    National Research Council Canada - National Science Library

    Lederman, S

    1983-01-01

    A preliminary investigation of the applicability of the spontaneous Raman diagnostic technique to the determination of the temperature of the propellant gases in the vicinity of the muzzle of a 2Omm...

  17. Cryogenic Propellant Storage and Transfer

    Data.gov (United States)

    National Aeronautics and Space Administration — Space Flight Demonstration development has been canceled in favor of a ground test bed development for of passive/active cryogenic propellant storage, transfer, and...

  18. Cavitation simulation on marine propellers

    DEFF Research Database (Denmark)

    Shin, Keun Woo

    Cavitation on marine propellers causes thrust breakdown, noise, vibration and erosion. The increasing demand for high-efficiency propellers makes it difficult to avoid the occurrence of cavitation. Currently, practical analysis of propeller cavitation depends on cavitation tunnel test, empirical...... criteria and inviscid flow method, but a series of model test is costly and the other two methods have low accuracy. Nowadays, computational fluid dynamics by using a viscous flow solver is common for practical industrial applications in many disciplines. Cavitation models in viscous flow solvers have been...... hydrofoils and conventional/highly-skewed propellers are performed with one of three cavitation models proven in 2D analysis. 3D cases also show accuracy and robustness of numerical method in simulating steady and unsteady sheet cavitation on complicated geometries. Hydrodynamic characteristics of cavitation...

  19. Mechanical properties, phenolic composition and extractability indices of Barbera grapes of different soluble solids contents from several growing areas.

    Science.gov (United States)

    Torchio, Fabrizio; Cagnasso, Enzo; Gerbi, Vincenzo; Rolle, Luca

    2010-02-15

    Phenolic compounds, extractable from grape skins and seeds, have a notable influence on the quality of red wines. Many studies have clearly demonstrated the relationship between the phenolic composition of the grape at harvest time and its influence on the phenolic composition of the red wine produced. In many previous works the evolution of phenolic composition and relative extractability was normally studied on grapes sampled at different times during ripening, but at the same date the physiological characteristics of grape berries in a vineyard are often very heterogeneous. Therefore, the main goal of the study is to investigate the differences among mechanical properties, phenolic composition and relative extractability of Vitis vinifera L. cv Barbera grape berries, harvested at the same date from several vineyards, and calibrated according to their density at three levels of soluble solids (A=235+/-8, B=252+/-8 and C=269+/-8 g L(-1) sugar) with the aim of studying the influence of ripeness stages and growing locations on these parameters. Results on mechanical properties showed that the thickness of the berry skin (Sp(sk)) was the parameter most affected by the different level of sugars in the pulp, while different skin hardnesses, evaluated by the break skin force (F(sk)), were related to the cultivation sites. The latter were also observed to influence the mechanical characteristics of seeds. Generally, the anthocyanin content increased with the level of soluble solids, while the increase in the tannin content of the berry skin and seeds was less marked. However, significant changes in flavanols reactive to vanillin in the seeds were found. The cellular maturity index (EA%) was little influenced by the soluble solids content of grapes. Copyright 2009 Elsevier B.V. All rights reserved.

  20. Solid-solution-like ZnO/C composites as excellent anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Zhang, Guanhua; Zhang, Hang; Zhang, Xiang; Zeng, Wei; Su, Qingmei; Du, Gaohui; Duan, Huigao

    2015-01-01

    Exploring advanced anode materials to maximize the capacity of lithium ion batteries has been an active research area for decades. Constructing composites materials has been proved to be one of the most effective methods to achieve higher capacity due to the synergistic effect. In this work, we proposed and demonstrated a concept of solid-solution-like ZnO/C composites to approach the largest possible synergistic effect by introducing the most interfaces and minimizing the pulverization. The solid-solution-like ZnO/C electrode could achieve a high reversible capacity of 813.3 mAh g −1 at a current density of 100 mA g −1 after 100 cycles with a decrease rate of only 0.4% per cycle. Moreover, the discharge capacity still maintained 53.5% of the original value even when the current density increased to 40 times as much as the original, showing a distinguished rate performance. In addition, such solid-solution-like nanofibers can be easily prepared because of their compatibility with the existing industrial PAN-based spinning process. This may pave the way to mass produce lithium ion batteries with significantly enhanced performance using existing low-cost commercial facilities and recipes.

  1. Composition of Solid Waste in Al Jabal Al Akhdar, a Mountain Region Undergoing Rapid Urbanization in Northern Oman

    Directory of Open Access Journals (Sweden)

    Abdullah I. Al-Mahrouqi

    2017-01-01

    Full Text Available There is a lack of data on the generation and composition of waste in rural areas worldwide. The present study analyzed the composition of solid waste in Al Jabal Al Akhdar, a rural mountain region in the Sultanate of Oman, which is presently experiencing a rapid rate of urbanization due to tourism development. The solid wastes here are generated by the municipality collecting waste from residential, commercial, institutional and recreational areas, the military from a training camp and a few non-governmental private companies from their camps and hotels. The whole load from each of the three sources was manually segregated each month from June 2013 – May 2014. The results indicated that plastic is the dominant category in the wastes collected by the municipality and accounts for 26.7%, followed by paper (17.9% and then food (14.4%. Food is the dominant category in the wastes collected by the military and private companies and accounts for 36.5% and 45.5% respectively. Management issues associated with solid waste are briefly considered. The study concluded that the municipality should implement an improved system for the collection of plastic waste and initiate a system for recycling it; the military and private companies should reduce the quantities of food waste by improved planning and management of the catering services.

  2. Experimental investigation of atomization characteristics of swirling spray by ADN gelled propellant

    Science.gov (United States)

    Guan, Hao-Sen; Li, Guo-Xiu; Zhang, Nai-Yuan

    2018-03-01

    Due to the current global energy shortage and increasingly serious environmental issues, green propellants are attracting more attention. In particular, the ammonium dinitramide (ADN)-based monopropellant thruster is gaining world-wide attention as a green, non-polluting and high specific impulse propellant. Gel propellants combine the advantages of liquid and solid propellants, and are becoming popular in the field of spaceflight. In this paper, a swirling atomization experimental study was carried out using an ADN aqueous gel propellant under different injection pressures. A high-speed camera and a Malvern laser particle size analyzer were used to study the spray process. The flow coefficient, cone angle of swirl atomizing spray, breakup length of spray membrane, and droplet size distribution were analyzed. Furthermore, the effects of different injection pressures on the swirling atomization characteristics were studied.

  3. Molecular composition of recycled organic wastes, as determined by solid-state {sup 13}C NMR and elemental analyses

    Energy Technology Data Exchange (ETDEWEB)

    Eldridge, S.M., E-mail: simon.eldridge@dpi.nsw.gov.au [Environmental Futures Centre, School of Environment, Griffith University, Nathan, QLD 4111 (Australia); NSW Department of Primary Industries, Bruxner Highway, Wollongbar, NSW 2477 (Australia); Chen, C.R. [Environmental Futures Centre, School of Environment, Griffith University, Nathan, QLD 4111 (Australia); Xu, Z.H. [Environmental Futures Centre, School of Biomolecular and Physical Sciences, Griffith University, Nathan, QLD 4111 (Australia); Nelson, P.N. [School of Earth and Environmental Sciences, James Cook University, Cairns, QLD 4870 (Australia); Boyd, S.E. [Environmental Futures Centre, School of Biomolecular and Physical Sciences, Griffith University, Nathan, QLD 4111 (Australia); Meszaros, I. [Formerly NSW Department of Primary Industries, Richmond, NSW 2753 (Australia); Chan, K.Y. [Graduate School of Environment, Macquarie University, North Ryde, NSW 2109 (Australia); Formerly NSW Department of Primary Industries, Richmond, NSW 2753 (Australia)

    2013-11-15

    Highlights: • Model estimated the molecular C components well for most RO wastes. • Molecular nature of organic matter in RO wastes varied widely. • Molecular composition by NMR modelling preferable to extraction techniques. • Some model shortcomings in estimating molecular composition of biochars. • Waste molecular composition important for carbon/nutrient outcomes in soil. - Abstract: Using solid state {sup 13}C NMR data and elemental composition in a molecular mixing model, we estimated the molecular components of the organic matter in 16 recycled organic (RO) wastes representative of the major materials generated in the Sydney basin area. Close correspondence was found between the measured NMR signal intensities and those predicted by the model for all RO wastes except for poultry manure char. Molecular nature of the organic matter differed widely between the RO wastes. As a proportion of organic C, carbohydrate C ranged from 0.07 to 0.63, protein C from <0.01 to 0.66, lignin C from <0.01 to 0.31, aliphatic C from 0.09 to 0.73, carbonyl C from 0.02 to 0.23, and char C from 0 to 0.45. This method is considered preferable to techniques involving imprecise extraction methods for RO wastes. Molecular composition data has great potential as a predictor of RO waste soil carbon and nutrient outcomes.

  4. Molecular composition of recycled organic wastes, as determined by solid-state 13C NMR and elemental analyses

    International Nuclear Information System (INIS)

    Eldridge, S.M.; Chen, C.R.; Xu, Z.H.; Nelson, P.N.; Boyd, S.E.; Meszaros, I.; Chan, K.Y.

    2013-01-01

    Highlights: • Model estimated the molecular C components well for most RO wastes. • Molecular nature of organic matter in RO wastes varied widely. • Molecular composition by NMR modelling preferable to extraction techniques. • Some model shortcomings in estimating molecular composition of biochars. • Waste molecular composition important for carbon/nutrient outcomes in soil. - Abstract: Using solid state 13 C NMR data and elemental composition in a molecular mixing model, we estimated the molecular components of the organic matter in 16 recycled organic (RO) wastes representative of the major materials generated in the Sydney basin area. Close correspondence was found between the measured NMR signal intensities and those predicted by the model for all RO wastes except for poultry manure char. Molecular nature of the organic matter differed widely between the RO wastes. As a proportion of organic C, carbohydrate C ranged from 0.07 to 0.63, protein C from <0.01 to 0.66, lignin C from <0.01 to 0.31, aliphatic C from 0.09 to 0.73, carbonyl C from 0.02 to 0.23, and char C from 0 to 0.45. This method is considered preferable to techniques involving imprecise extraction methods for RO wastes. Molecular composition data has great potential as a predictor of RO waste soil carbon and nutrient outcomes

  5. Retraction of 'Composition design and mechanical properties of BCC Ti solid solution alloys with low Young's modulus'

    International Nuclear Information System (INIS)

    Tulugan, Keli Mu; Park, Cheol Hong; Park, Won Jo; Qing, Wang

    2012-01-01

    The article 'Composition design and mechanical properties of BCC Ti solid solution alloys with low Young's modulus' has been retracted upon the request of the third author (Prof. Wang Qing, the first author's former advisor during his internship at DaLian University of Technology). The article was published without the third author's knowledge and consent. The corresponding author (Prof. Wonjo Park) apologizes to the third author, to the readers, and to the editorial staff of the JMST. The JMST editorial board does not tolerate such actions from authors and we will take appropriate action to prevent this from happening in the future

  6. Flexible poly(ethylene carbonate)/garnet composite solid electrolyte reinforced by poly(vinylidene fluoride-hexafluoropropylene) for lithium metal batteries

    Science.gov (United States)

    He, Zijian; Chen, Long; Zhang, Bochen; Liu, Yongchang; Fan, Li-Zhen

    2018-07-01

    Solid-state electrolytes with high ionic conductivities, great flexibility, and easy processability are needed for high-performance solid-state rechargeable lithium batteries. In this work, we synthesize nanosized cubic Li6.25Al0.25La3Zr2O12 (LLZO) by solution combustion method and develop a flexible garnet-based composite solid electrolyte composed of LLZO, poly(ethylene carbonate) (PEC), poly(vinylidene fluoride-hexafluoropropylene) (P(VdF-HFP) and lithium bis(fluorosulfonyl)imide (LiFSI)). In the flexible composite solid electrolytes, LLZO nanoparticles, as ceramic matrix, have a positive effect on ionic conductivities and lithium ion transference number (tLi+). PEC, as a fast ion-conducting polymer, possesses high tLi+ inherently. P(VdF-HFP), as a binder, can strengthen mechanical properties. Consequently, the as-prepared composite solid electrolyte demonstrates high tLi+ (0.82) and superb thermal stability (remaining LLZO matrix after burning). All-solid-state LiFePO4|Li cells assembled with the flexible composite solid electrolyte deliver a high initial discharge specific capacity of 121.4 mAh g-1 and good cycling stability at 55 °C.

  7. All-solid-state flexible supercapacitors based on highly dispersed polypyrrole nanowire and reduced graphene oxide composites.

    Science.gov (United States)

    Yu, Chenfei; Ma, Peipei; Zhou, Xi; Wang, Anqi; Qian, Tao; Wu, Shishan; Chen, Qiang

    2014-10-22

    Highly dispersed polypyrrole nanowires are decorated on reduced graphene oxide sheets using a facile in situ synthesis route. The prepared composites exhibit high dispersibility, large effective surface area, and high electric conductivity. All-solid-state flexible supercapacitors are assembled based on the prepared composites, which show excellent electrochemical performances with a specific capacitance of 434.7 F g(-1) at a current density of 1 A g(-1). The as-fabricated supercapacitor also exhibits excellent cycling stability (88.1% capacitance retention after 5000 cycles) and exceptional mechanical flexibility. In addition, outstanding power and energy densities were obtained, demonstrating the significant potential of prepared material for flexible and portable energy storage devices.

  8. Modified fly ash from municipal solid waste incineration as catalyst support for Mn-Ce composite oxides

    Science.gov (United States)

    Chen, Xiongbo; Liu, Ying; Yang, Ying; Ren, Tingyan; Pan, Lang; Fang, Ping; Chen, Dingsheng; Cen, Chaoping

    2017-08-01

    Fly ash from municipal solid waste incineration was modified by hydrothermal treatment and used as catalyst support for Mn-Ce composite oxides. The prepared catalyst showed good activity for the selective catalytic reduction (SCR) of NO by NH3. A NO conversion of 93% could be achieved at 300 °C under a GHSV of 32857 h-1. With the help of characterizations including XRD, BET, SEM, TEM, XPS and TPR, it was found that hydrothermal treatment brought a large surface area and abundant mesoporous to the modified fly ash, and Mn-Ce composite oxides were highly dispersed on the surface of the support. These physical and chemical properties were the intrinsic reasons for the good SCR activity. This work transformed fly ash into high value-added products, providing a new approach to the resource utilization and pollution control of fly ash.

  9. Conductivity And Thermal Stability of Solid Acid Composites CsH2PO4 /NaH2PO4/ SiO2

    International Nuclear Information System (INIS)

    Norsyahida Mohammad; Abu Bakar Mohamad; Abu Bakar Mohamad; Abdul Amir Hassan Kadhum

    2016-01-01

    Solid acid composites CsH 2 PO 4 / NaH 2 PO 4 / SiO 2 with different mole ratios of CsH 2 PO 4 and NaH 2 PO 4 to SiO 2 were synthesized and characterized. Preliminary infrared measurements of CsH 2 PO 4 and its composites indicated that hydrogen bonds breaking and formation were detected between 1710 to 2710 cm -1 , while the rotation of phosphate tetrahedral anions occurred between 900 and 1200 cm -1 . The superprotonic transition of CsH 2 PO 4 / NaH 2 PO 4 / SiO 2 composite was identified at superprotonic temperatures between 230 and 260 degree Celcius, under atmospheric pressure. This study reveals higher conductivity values for composites with higher CsH 2 PO 4 (CDP) content. Solid acid composite CDP 613 appeared as the composite with the highest conductivity that is 7.2x10 -3 S cm -1 at 230 degree Celcius. Thermal stability of the solid acid composites such as temperature of dehydration, melting and decomposition were investigated. The addition of NaH 2 PO 4 lowers the dehydration temperature of the solid acid composites. (author)

  10. Propelling Extended Objects

    Science.gov (United States)

    Humbert, Richard

    2010-01-01

    A force acting on just part of an extended object (either a solid or a volume of a liquid) can cause all of it to move. That motion is due to the transmission of the force through the object by its material. This paper discusses how the force is distributed to all of the object by a gradient of stress or pressure in it, which creates the local…

  11. Understanding the vapor-liquid-solid growth and composition of ternary III-V nanowires and nanowire heterostructures

    Science.gov (United States)

    Dubrovskii, V. G.

    2017-11-01

    Based on the recent achievements in vapor-liquid-solid (VLS) synthesis, characterization and modeling of ternary III-V nanowires and axial heterostructures within such nanowires, we try to understand the major trends in their compositional evolution from a general theoretical perspective. Clearly, the VLS growth of ternary materials is much more complex than in standard vapor-solid epitaxy techniques, and even maintaining the necessary control over the composition of steady-state ternary nanowires is far from straightforward. On the other hand, VLS nanowires offer otherwise unattainable material combinations without introducing structural defects and hence are very promising for next-generation optoelectronic devices, in particular those integrated with a silicon electronic platform. In this review, we consider two main problems. First, we show how and by means of which parameters the steady-state composition of Au-catalyzed or self-catalyzed ternary III-V nanowires can be tuned to a desired value and why it is generally different from the vapor composition. Second, we present some experimental data and modeling results for the interfacial abruptness across axial nanowire heterostructures, both in Au-catalyzed and self-catalyzed VLS growth methods. Refined modeling allows us to formulate some general growth recipes for suppressing the unwanted reservoir effect in the droplet and sharpening the nanowire heterojunctions. We consider and refine two approaches developed to date, namely the regular crystallization model for a liquid alloy with a critical size of only one III-V pair at high supersaturations or classical binary nucleation theory with a macroscopic critical nucleus at modest supersaturations.

  12. Agglomerates, smoke oxide particles, and carbon inclusions in condensed combustion products of an aluminized GAP-based propellant

    Science.gov (United States)

    Ao, Wen; Liu, Peijin; Yang, Wenjing

    2016-12-01

    In solid propellants, aluminum is widely used to improve the performance, however the condensed combustion products especially the large agglomerates generated from aluminum combustion significantly affect the combustion and internal flow inside the solid rocket motor. To clarify the properties of the condensed combustion products of aluminized propellants, a constant-pressure quench vessel was adopted to collect the combustion products. The morphology and chemical compositions of the collected products, were then studied by using scanning electron microscopy coupled with energy dispersive (SEM-EDS) method. Various structures have been observed in the condensed combustion products. Apart from the typical agglomerates or smoke oxide particles observed before, new structures including the smoke oxide clusters, irregular agglomerates and carbon-inclusions are discovered and investigated. Smoke oxide particles have the highest amount in the products. The highly dispersed oxide particle is spherical with very smooth surface and is on the order of 1-2 μm, but due to the high temperature and long residence time, these small particles will aggregate into smoke oxide clusters which are much larger than the initial particles. Three types of spherical agglomerates have been found. As the ambient gas temperature is much higher than the boiling point of Al2O3, the condensation layer inside which the aluminum drop is burning would evaporate quickly, which result in the fact that few "hollow agglomerates" has been found compared to "cap agglomerates" and "solid agglomerates". Irregular agglomerates usually larger than spherical agglomerates. The formation of irregular agglomerates likely happens by three stages: deformation of spherical aluminum drops; combination of particles with various shape; finally production of irregular agglomerates. EDS results show the ratio of O to Al on the surface of agglomerates is lower in comparison to smoke oxide particles. C and O account for

  13. Strontium Titanate-based Composite Anodes for Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Blennow Tullmar, Peter; Kammer Hansen, Kent; Wallenberg, L.R.

    2008-01-01

    Surfactant-assisted infiltration of Gd-doped ceria (CGO) in Nb-doped SrTiO3 (STN) was investigated as a potential fuel electrode for solid oxide fuel cells (SOFC). An electronically conductive backbone structure of STN was first fabricated at high temperatures and then combined with the mixed con...

  14. Ab initio study of compositional trends in solid solution strengthening in metals with low Peierls stresses

    Czech Academy of Sciences Publication Activity Database

    Ma, D.; Friák, Martin; von Pezold, J.; Neugebauer, J.; Raabe, D.

    2015-01-01

    Roč. 98, OCT (2015), s. 367-376 ISSN 1359-6454 Institutional support: RVO:68081723 Keywords : DFT * alloys * Mg alloys * Ni alloys * Mg basal slip Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 5.058, year: 2015

  15. The composition of semi-finished inventories at a solid board plant

    NARCIS (Netherlands)

    Wanders, H.L.T.; Gaalman, G.J.C.; Sierksma, G.

    2004-01-01

    A solid board factory produces rectangular sheets of cardboard in two different formats, namely large formats and small formats. The production process consists of two stages separated by an inventory point. In the first stage, a cardboard machine produces the large formats. In the second stage a

  16. The effect of saliva composition on texture perception of semi-solids

    NARCIS (Netherlands)

    Engelen, L.; Keybus, P.A.M. van den; Wijk, R.A. de; Veerman, E.C.I.; Amerongen, A.V.N.; Bosman, F.; Prinz, J.F.; Bilt, A. van der

    2007-01-01

    Saliva is expected to be of significance for the perception of food stimuli in the mouth. Mixing the food with saliva, including breakdown and dilution, is considered to be of large importance for semi-solids as these products are masticated without chewing. It is known that there are large

  17. Effects of early rumen development and solid feed composition on growth performance and abomasal health in veal calves.

    Science.gov (United States)

    Berends, H; van Reenen, C G; Stockhofe-Zurwieden, N; Gerrits, W J J

    2012-06-01

    The experiment was designed to study the importance of early rumen development and of the composition of solid feed intake on growth performance and abomasal health in milk-fed veal calves. One hundred and six Holstein-Friesian male calves were included in the experiment, and studied during 2 successive 12-wk periods (period 1 and period 2). In a 2 × 2 factorial arrangement, effects of partially replacing milk replacer by solid feed during period 1 and partially replacing dry matter (DM) intake from maize silage and barley straw by concentrate during period 2 were tested. Solid feed during period 1 consisted of maize silage, barley straw, and concentrate (25:25:50 on a DM basis). Solid feed during period 2 consisted of maize silage and barley straw (50:50 ratio on DM basis) for the nonconcentrate groups, and maize silage, barley straw and concentrates (25:25:50 on a DM basis) for the concentrate groups. At the end of period 1 (n=16) and at the end of period 2 (n=90), parameters of animal performance, rumen development, rumen fermentation, ruminal drinking, and abomasal damage were examined. Partially replacing milk replacer by solid feed during period 1 resulted in early rumen development (ERD) at the end of period 1, characterized by increased rumen weight, and an increased epithelial and absorptive surface area. Both ERD and partially replacing roughage by concentrates in period 2 increased the rumen development score at the end of period 2. Although ERD calves consumed more solid feed and less milk replacer during period 1 and 2 than non-ERD calves, carcass weight gains at 25 wk were identical, and utilization of the solid feed provided appeared similar to that of milk replacer. Partially replacing roughage by concentrates in period 2 increased dressing percentage and warm carcass weight. Plaque formation at the rumen mucosa was unaffected by ERD or partially replacing roughage by concentrates and generally low in all calves. The prevalence of large scars in

  18. Novel powder/solid composites possessing low Young’s modulus and tunable energy absorption capacity, fabricated by electron beam melting, for biomedical applications

    International Nuclear Information System (INIS)

    Ikeo, Naoko; Ishimoto, Takuya; Nakano, Takayoshi

    2015-01-01

    Highlights: • We fabricated novel porous composites by electron beam melting. • The composites consist of necked powder and melted solid framework. • Unmelted powder that is usually discarded was mechanically functionalized by necking. • The composites possess controllably low Young’s modulus and excellent toughness. • The composites would be promising for utilization in biomedical applications. - Abstract: A novel, hierarchical, porous composite from a single material composed of necked powder and melted solid, with tunable mechanical properties, is fabricated by electron beam melting and subsequent heat treatment. The composite demonstrates low Young’s modulus (⩽31 GPa) and excellent energy absorption capacity, both of which are necessary for use in orthopedic applications. To the best of our knowledge, this is the first report on the synthesis of a material combining controllably low Young’s modulus and excellent toughness

  19. Online gas composition estimation in solid oxide fuel cell systems with anode off-gas recycle configuration

    Science.gov (United States)

    Dolenc, B.; Vrečko, D.; Juričić, Ð.; Pohjoranta, A.; Pianese, C.

    2017-03-01

    Degradation and poisoning of solid oxide fuel cell (SOFC) stacks are continuously shortening the lifespan of SOFC systems. Poisoning mechanisms, such as carbon deposition, form a coating layer, hence rapidly decreasing the efficiency of the fuel cells. Gas composition of inlet gases is known to have great impact on the rate of coke formation. Therefore, monitoring of these variables can be of great benefit for overall management of SOFCs. Although measuring the gas composition of the gas stream is feasible, it is too costly for commercial applications. This paper proposes three distinct approaches for the design of gas composition estimators of an SOFC system in anode off-gas recycle configuration which are (i.) accurate, and (ii.) easy to implement on a programmable logic controller. Firstly, a classical approach is briefly revisited and problems related to implementation complexity are discussed. Secondly, the model is simplified and adapted for easy implementation. Further, an alternative data-driven approach for gas composition estimation is developed. Finally, a hybrid estimator employing experimental data and 1st-principles is proposed. Despite the structural simplicity of the estimators, the experimental validation shows a high precision for all of the approaches. Experimental validation is performed on a 10 kW SOFC system.

  20. Propeller Flaps: A Literature Review.

    Science.gov (United States)

    Sisti, Andrea; D'Aniello, Carlo; Fortezza, Leonardo; Tassinari, Juri; Cuomo, Roberto; Grimaldi, Luca; Nisi, Giuseppe

    2016-01-01

    Since their introduction in 1991, propeller flaps are increasingly used as a surgical approach to loss of substance. The aim of this study was to evaluate the indications and to verify the outcomes and the complication rates using this reconstructing technique through a literature review. A search on PubMed was performed using "propeller flap", "fasciocutaneous flap", "local flap" or "pedicled flap" as key words. We selected clinical studies using propeller flaps as a reconstructing technique. We found 119 studies from 1991 to 2015. Overall, 1,315 propeller flaps were reported in 1,242 patients. Most frequent indications included loss of substance following tumor excision, repair of trauma-induced injuries, burn scar contractures, pressure sores and chronic infections. Complications were observed in 281/1242 patients (22.6%) occurring more frequently in the lower limbs (31.8%). Partial flap necrosis and venous congestion were the most frequent complications. The complications' rate was significantly higher in infants (70 years old) but there was not a significant difference between the sexes. Trend of complication rate has not improved during the last years. Propeller flaps showed a great success rate with low morbidity, quick recovery, good aesthetic outcomes and reduced cost. The quality and volume of the transferred soft tissue, the scar orientation and the possibility of direct donor site closure should be considered in order to avoid complications. Indications for propeller flaps are small- or medium-sized defects located in a well-vascularized area with healthy surrounding tissues. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  1. A novel solid-state electrochemiluminescence quenching sensor for detection of aniline based on luminescent composite nanofibers

    International Nuclear Information System (INIS)

    Wang, Xiaoying; Yang, Yu; Gao, Huiwen

    2014-01-01

    A novel solid-state electrochemiluminescence (ECL) quenching sensor based on the luminescent composite nanofibers for detection of aniline has been developed. The gold nanoparticles (AuNPs) and Ruthenium (II) tris-(bipyridine) (Ru(bpy) 3 2+ ) doped nylon 6 (PA6) luminescent composite nanofibers (Ru–AuNPs–PA6) were successfully deposited to the bare glassy carbon (GC) electrode by a one-step electrospinning technique. The Ru–AuNPs–PA6 nanofibers maintained the photoelectric properties of the Ru(bpy) 3 2+ ions completely and exhibited excellent ECL behaviors. A high quenching effect on the ECL signal of the Ru–AuNPs–PA6/C 2 O 4 2− system was obtained with the presence of low concentration aniline compounds. The potential of analytical application was explored by use of the inhibited ECL. The quenching efficiencies of the five kinds of aniline compounds were compared by monitoring the aniline-dependent ECL intensity change. The magnitude of quenching depended linearly upon the concentration of aniline in the investigated concentration range of 10–10 µM. The detection limit for aniline is 5.0 nM, which is comparable or better than that in the reported assays. The solid-state ECL quenching sensor exhibited high sensitivity and good stability. This study may provide new insight into the design of advanced electrospun nanofibers-based ECL sensors for detection and analysis of a variety of active molecules. - Highlights: • The Ru–AuNPs–PA6 nanofibers were first prepared by one-step electrospinning technique. • The Ru–AuNPs–PA6 nanofibers exhibited excellent ECL behaviors on GC electrodes. • It is the first solid-state ECL sensor based on nanofibers for aniline detection. • The quenching efficiencies of the five kinds of aniline compounds were compared. • The strategy could be extended to develop various nanofibers-based ECL sensors

  2. Laser-propelled ram accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Sasoh, A. [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science

    2000-11-01

    The concept of 'laser-propelled ram accelerator (L-RAMAC)' is proposed. Theoretically it is capable of achieving a higher launch speed than that by a chemical ram accelerator because a higher specific energy can be input to the propellant gas. The laser beam is supplied through the muzzle, focused as an annulus behind the base of the projectile. The performance of L-RAMAC is analized based on generalized Rankine-Hugoniot relations, suggesting that a superorbital muzzle speed is achievable out of this device. (orig.)

  3. Solid-phase photocatalytic degradation of polyethylene-goethite composite film under UV-light irradiation

    International Nuclear Information System (INIS)

    Liu, G.L.; Zhu, D.W.; Liao, S.J.; Ren, L.Y.; Cui, J.Z.; Zhou, W.B.

    2009-01-01

    A novel photodegradable polyethylene-goethite (PE-goethite) composite film was prepared by embedding the goethite into the commercial polyethylene. The degradation of PE-goethite composite films was investigated under ultraviolet light irradiation. The photodegradation activity of the PE plastic was determined by monitoring its weight loss, scanning electron microscopic (SEM) analysis and FT-IR spectroscopy. The weight of PE-goethite (1 wt%) sample steadily decreased and led to the total 16% reduction in 300 h under UV-light intensity for 1 mW/cm 2 . Through SEM observation there were some cavities around the goethite powder in the composite films, but there were few changes except some surface chalking phenomenon in pure PE film. The degradation rate could be controlled by changing the concentration of goethite particles in PE plastic. The degradation of composite plastic initiated on PE-goethite interface and then extended into polymer matrix induced by the diffusion of the reactive oxygen species generated on goethite particle surface. The photocatalytic degradation mechanism of the composite films was briefly discussed.

  4. Solid state double layer capacitor based on a polyether polymer electrolyte blend and nanostructured carbon black electrode composites

    Energy Technology Data Exchange (ETDEWEB)

    Lavall, Rodrigo L.; Borges, Raquel S.; Calado, Hallen D.R.; Welter, Cezar; Trigueiro, Joao P.C.; Silva, Glaura G. [Departamento de Quimica, Instituto de Ciencias Exatas, Universidade Federal de Minas Gerais, CEP 31270-901, Belo Horizonte (Brazil); Rieumont, Jacques [Departamento de Quimica, Instituto de Ciencias Exatas, Universidade Federal de Minas Gerais, CEP 31270-901, Belo Horizonte (Brazil); Facultad de Quimica, Universidad de La Habana, Habana 10400 (Cuba); Neves, Bernardo R.A. [Departamento de Fisica, Instituto de Ciencias Exatas, Universidade Federal de Minas Gerais, CEP 31270-901, Belo Horizonte (Brazil)

    2008-03-01

    An all solid double layer capacitor was assembled by using poly(ethylene oxide)/poly(propylene glycol)-b-poly(ethylene glycol)-b-poly(propylene glycol)-bis(2-aminopropyl ether) blend (PEO-NPPP) and LiClO{sub 4} as polymer electrolyte layer and PEO-NPPP-carbon black (CB) as electrode film. High molecular weight PEO and the block copolymer NPPP with molecular mass of 2000 Da were employed, which means that the design is safe from the point of view of solvent or plasticizer leakage and thus, a separator is not necessary. Highly conductive with large surface area nanostructured carbon black was dispersed in the polymer blend to produce the electrode composite. The electrolyte and electrode multilayers prepared by spray were studied by differential scanning calorimetry, atomic force microscopy (AFM) and impedance spectroscopy. The ionic conductivity as a function of temperature was fitted with the Williams-Landel-Ferry equation, which indicates a conductivity mechanism typical of solid polymer electrolyte. AFM images of the nanocomposite electrode showed carbon black particles of approximately 60 nm in size well distributed in a semicrystalline and porous polymer blend coating. The solid double layer capacitor with 10 wt.% CB was designed with final thickness of approximately 130 {mu}m and delivered a capacitance of 17 F g{sup -1} with a cyclability of more than 1000 cycles. These characteristics make possible the construction of a miniature device in complete solid state which will avoid electrolyte leakage and present a performance superior to other similar electric double layer capacitors (EDLCs) presented in literature, as assessed in specific capacitance by total carbon mass. (author)

  5. Large Propellant Tank Cryo-Cooler (LPTC)

    Data.gov (United States)

    National Aeronautics and Space Administration — In rocket test and launch facilities, cryogenic propellants stored in tanks boils off due to heat leakage, with the following impacts:Ø   Waste, propellants boil off...

  6. Quadcopter thrust optimization with ducted-propeller

    Directory of Open Access Journals (Sweden)

    Kuantama Endrowednes

    2017-01-01

    Full Text Available In relation to quadcopter body frame model, propeller can be categorized into propeller with ducted and without ducted. This study present differences between those two using CFD (Computational Fluid Dynamics method. Both categories utilize two blade-propeller with diameter of 406 (mm. Propeller rotation generates acceleration per time unit on the volume of air. Based on the behavior of generated air velocity, ducted propeller can be modeled into three versions. The generated thrust and performance on each model were calculated to determine the best model. The use of ducted propeller increases the total weight of quadcopter and also total thrust. The influence of this modeling were analyzed in detail with variation of angular velocity propeller from 1000 (rpm to 9000 (rpm. Besides the distance between propeller tip and ducted barrier, the size of ducted is also an important part in thrust optimization and total weight minimization of quadcopter.

  7. Seawater Immersion of GEM II Propellant

    National Research Council Canada - National Science Library

    Merrill, Calude

    1999-01-01

    ... (% AP lost/week aged in seawater) and intercepts that depend on sample size. Friction and impact data on dried aged propellant samples showed no increased burning hazard compared with propellant not exposed to water...

  8. Statistical analysis of solid waste composition data: Arithmetic mean, standard deviation and correlation coefficients

    DEFF Research Database (Denmark)

    Edjabou, Maklawe Essonanawe; Martín-Fernández, Josep Antoni; Scheutz, Charlotte

    2017-01-01

    -derived food waste amounted to 2.21 ± 3.12% with a confidence interval of (−4.03; 8.45), which highlights the problem of the biased negative proportions. A Pearson’s correlation test, applied to waste fraction generation (kg mass), indicated a positive correlation between avoidable vegetable food waste...... and plastic packaging. However, correlation tests applied to waste fraction compositions (percentage values) showed a negative association in this regard, thus demonstrating that statistical analyses applied to compositional waste fraction data, without addressing the closed characteristics of these data......, have the potential to generate spurious or misleading results. Therefore, ¨compositional data should be transformed adequately prior to any statistical analysis, such as computing mean, standard deviation and correlation coefficients....

  9. Composition variability of the organic fraction of municipal solid waste and effects on hydrogen and methane production potentials.

    Science.gov (United States)

    Alibardi, Luca; Cossu, Raffaello

    2015-02-01

    The composition of the Organic Fraction of Municipal Solid Waste (OFMSW) strongly depends on the place and time of collection for a specific municipality or area. Moreover synthetic food waste or organic waste from cafeterias and restaurants may not be representative of the overall OFMSW received at treatment facilities for source-separated waste. This work is aimed at evaluating the composition variability of OFMSW, the potential productions of hydrogen and methane from specific organic waste fractions typically present in MSW and the effects of waste composition on overall hydrogen and methane yields. The organic waste fractions considered in the study were: bread-pasta, vegetables, fruits, meat-fish-cheese and undersieve 20mm. Composition analyses were conducted on samples of OFMSW that were source segregated at household level. Batch tests for hydrogen and methane productions were carried out under mesophilic conditions on selected fractions and OFMSW samples. Results indicated that the highest production of hydrogen was achieved by the bread-pasta fraction while the lowest productions were measured for the meat-fish-cheese fraction. The results indicated that the content of these two fractions in organic waste had a direct influence on the hydrogen production potentials of OFMSW. The higher the content of bread-pasta fraction, the higher the hydrogen yields were while the contrary was observed for the meat-fish-cheese fraction. The definition of waste composition therefore represents fundamental information to be reported in scientific literature to allow data comparison. The variability of OFMSW and its effects on hydrogen potentials might also represents a problematic issue in the management of pilot or full-scale plants for the production of hydrogen by dark fermentation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Sample preparation composite and replicate strategy case studies for assay of solid oral drug products.

    Science.gov (United States)

    Nickerson, Beverly; Harrington, Brent; Li, Fasheng; Guo, Michele Xuemei

    2017-11-30

    Drug product assay is one of several tests required for new drug products to ensure the quality of the product at release and throughout the life cycle of the product. Drug product assay testing is typically performed by preparing a composite sample of multiple dosage units to obtain an assay value representative of the batch. In some cases replicate composite samples may be prepared and the reportable assay value is the average value of all the replicates. In previously published work by Harrington et al. (2014) [5], a sample preparation composite and replicate strategy for assay was developed to provide a systematic approach which accounts for variability due to the analytical method and dosage form with a standard error of the potency assay criteria based on compendia and regulatory requirements. In this work, this sample preparation composite and replicate strategy for assay is applied to several case studies to demonstrate the utility of this approach and its application at various stages of pharmaceutical drug product development. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Physico-chemical properties of Brazilian cocoa butter and industrial blends. Part I Chemical composition, solid fat content and consistency

    Directory of Open Access Journals (Sweden)

    Ribeiro, A. P. B.

    2012-03-01

    Full Text Available A comparative study of the primary properties of six cocoa butter samples, representative of industrial blends and cocoa butter extracted from fruits cultivated in different geographical areas in Brazil is presented. The samples were evaluated according to fatty acid composition, triacylglycerol composition, regiospecific distribution, melting point, solid fat content and consistency. The results allowed for differentiating the samples according to their chemical compositions, thermal resistance properties, hardness characteristics, as well as technological adequacies and potential use in regions with tropical climates.

    En este trabajo se presenta un estudio comparativo de las propiedades primarias de mantecas de cacao, representativas de las mezclas industriales, y de la manteca de cacao original de diferentes zonas geográficas de Brasil. Las muestras fueron evaluadas de acuerdo a la composición de ácidos grasos, composición de triglicéridos, distribución de los ácidos grasos en las moléculas de triglicéridos, punto de fusión, contenido de grasa sólida y consistencia. Los resultados permitieron diferenciar las muestras por su composición química, propiedades de resistencia térmica, características de dureza, así como en materia de adecuaciones tecnológicas y los usos potenciales en las regiones de clima tropical.

  12. Case study on prediction of remaining methane potential of landfilled municipal solid waste by statistical analysis of waste composition data.

    Science.gov (United States)

    Sel, İlker; Çakmakcı, Mehmet; Özkaya, Bestamin; Suphi Altan, H

    2016-10-01

    Main objective of this study was to develop a statistical model for easier and faster Biochemical Methane Potential (BMP) prediction of landfilled municipal solid waste by analyzing waste composition of excavated samples from 12 sampling points and three waste depths representing different landfilling ages of closed and active sections of a sanitary landfill site located in İstanbul, Turkey. Results of Principal Component Analysis (PCA) were used as a decision support tool to evaluation and describe the waste composition variables. Four principal component were extracted describing 76% of data set variance. The most effective components were determined as PCB, PO, T, D, W, FM, moisture and BMP for the data set. Multiple Linear Regression (MLR) models were built by original compositional data and transformed data to determine differences. It was observed that even residual plots were better for transformed data the R(2) and Adjusted R(2) values were not improved significantly. The best preliminary BMP prediction models consisted of D, W, T and FM waste fractions for both versions of regressions. Adjusted R(2) values of the raw and transformed models were determined as 0.69 and 0.57, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Structural, electrical conductivity and dielectric behavior of Na2SO4–LDT composite solid electrolyte

    Directory of Open Access Journals (Sweden)

    Mohd Z. Iqbal

    2016-01-01

    Full Text Available A series of composite materials of general molecular formula (1 − x Na2SO4 − (x LDT was prepared by solid state reaction method. The phase structure and functionalization of these materials were defined by X-ray diffraction (XRD and Fourier-transform infrared spectroscopy (FT-IR respectively. Differential thermal analysis (DTA revealed that the hump of phase transition at 250 °C has decreased while its thermal stability was enhanced. Scanning electron microscopy signifies the presence of improved rigid surfaces and interphases that are accountable for the high ionic conduction due to dispersion of LDT particles in the composite systems. Arrhenius plots of the conductance show the maximum conductivity, σ = 4.56 × 10−4 S cm−1 at 500 °C for the x = 0.4 composition with the lowest activation energy 0.34 eV in the temperature range of 573–773 K. The value of dielectric constant was decreased with increasing frequency and follows the usual trend.

  14. Propelling arboriculture into the future

    Science.gov (United States)

    E. Gregory McPherson

    2011-01-01

    Research is the engine that propels arboriculture and urban forestry into the future. New knowledge, technologies, and tools provide arborists with improved tree care practices that result in healthier urban forests. The ISA Science and Research Committee (SRC) is composed of 13 professionals and researchers who are dedicated to elevating the importance of research...

  15. Plasma ignition of LOVA propellants

    NARCIS (Netherlands)

    Driel, C.A. van; Boluijt, A.G.; Schilt, A.

    2010-01-01

    Ignition experiments were performed using a gun simulator which is equipped with a burst disk. This equipment facilitates the application of propellant loading densities which are comparable to those applied in regular ammunitions. For this study the gun simulator was equipped with a plasma jet

  16. THE PROPELLER AND THE FROG

    International Nuclear Information System (INIS)

    Pan, Margaret; Chiang, Eugene

    2010-01-01

    'Propellers' in planetary rings are disturbances in ring material excited by moonlets that open only partial gaps. We describe a new type of co-orbital resonance that can explain the observed non-Keplerian motions of propellers. The resonance is between the moonlet underlying the propeller and co-orbiting ring particles downstream of the moonlet where the gap closes. The moonlet librates within the gap about an equilibrium point established by co-orbiting material and stabilized by the Coriolis force. In the limit of small libration amplitude, the libration period scales linearly with the gap azimuthal width and inversely as the square root of the co-orbital mass. The new resonance recalls but is distinct from conventional horseshoe and tadpole orbits; we call it the 'frog' resonance, after the relevant term in equine hoof anatomy. For a ring surface density and gap geometry appropriate for the propeller Bleriot in Saturn's A ring, our theory predicts a libration period of ∼4 years, similar to the ∼3.7 year period over which Bleriot's orbital longitude is observed to vary. These librations should be subtracted from the longitude data before any inferences about moonlet migration are made.

  17. Method of making sulfur tolerant composite cermet electrodes for solid oxide electrochemical cells

    Science.gov (United States)

    Isenberg, Arnold O.

    1989-01-01

    An electrochemical apparatus is made containing an exterior electorde bonded to the exterior of a tubular, solid, oxygen ion conducting electrolyte where the electrolyte is also in contact with an interior electrode, said exterior electrode comprising particles of an electronic conductor contacting the electrolyte, where a ceramic metal oxide coating partially surrounds the particles and is bonded to the electrolyte, and where a coating of an ionic-electronic conductive material is attached to the ceramic metal oxide coating and to the exposed portions of the particles.

  18. Highly compressible and all-solid-state supercapacitors based on nanostructured composite sponge.

    Science.gov (United States)

    Niu, Zhiqiang; Zhou, Weiya; Chen, Xiaodong; Chen, Jun; Xie, Sishen

    2015-10-21

    Based on polyaniline-single-walled carbon nanotubes -sponge electrodes, highly compressible all-solid-state supercapacitors are prepared with an integrated configuration using a poly(vinyl alcohol) (PVA)/H2 SO4 gel as the electrolyte. The unique configuration enables the resultant supercapacitors to be compressed as an integrated unit arbitrarily during 60% compressible strain. Furthermore, the performance of the resultant supercapacitors is nearly unchanged even under 60% compressible strain. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Structural and compositional characterization of synthetic (Ca,Sr)-tremolite and (Ca,Sr)-diopside solid solutions

    Science.gov (United States)

    Gottschalk, M.; Najorka, J.; Andrut, M.

    Tremolite (CaxSr1-x)2Mg5[Si8O22/(OH)2] and diopside (CaxSr1-x)Mg[Si2O6] solid solutions have been synthesized hydrothermally in equilibrium with a 1 molar (Ca,Sr)Cl2 aqueous solution at 750°C and 200 MPa. The solid run products have been investigated by optical, electron scanning and high resolution transmission electron microscopy, electron microprobe, X-ray-powder diffraction and Fourier-transform infrared spectroscopy. The synthesized (Ca,Sr)-tremolites are up to 2000 µm long and 30 µm wide, the (Ca,Sr)-diopsides are up to 150 µm long and 20 µm wide. In most runs the tremolites and diopsides are well ordered and chain multiplicity faults are rare. Nearly pure Sr-tremolite (tr0.02Sr-tr0.98) and Sr-diopside (di0.01Sr-di0.99) have been synthesized. A continuous solid solution series, i.e. complete substitution of Sr2+ for Ca2+ on M4-sites exists for (Ca,Sr)-tremolite. Total substitution of Sr2+ for Ca2+ on M2-sites can be assumed for (Ca,Sr)-diopsides. For (Ca,Sr)-tremolites the lattice parameters a, b and β are linear functions of composition and increase with Sr-content whereas c is constant. For the diopside series all 4 lattice parameters are a linear function of composition; a, b, c increase and β decreases with rising Sr-content. The unit cell volume for tremolite increases 3.47% from 906.68 Å3 for tremolite to 938.21 Å3 for Sr-tremolite. For diopside the unit cell volume increases 4.87 % from 439.91 Å3 for diopside to 461.30 Å3 for Sr-diopside. The observed splitting of the OH stretching band in tremolite is caused by different configurations of the next nearest neighbors (multi mode behavior). Resolved single bands can be attributed to the following configurations on the M4-sites: SrSr, SrCa, CaCa and CaMg. The peak positions of these 4 absorption bands are a linear function of composition. They are shifted to lower wavenumbers with increasing Sr-content. No absorption band due to the SrMg configuration on the M4-site is observed. This indicates

  20. Functional regulation of Pb-Ti/MoS_2 composite coatings for environmentally adaptive solid lubrication

    International Nuclear Information System (INIS)

    Ren, Siming; Li, Hao; Cui, Mingjun; Wang, Liping; Pu, Jibin

    2017-01-01

    Highlights: • Co-doped Pb-Ti/MoS_2 composite coatings were successfully fabricated by unbalanced magnetron sputtering system. • Co-doped Pb-Ti/MoS_2 composite coatings showed lower friction coefficient and longer wear life in both humid and vacuum environments than that of single-doped ones. • The wear behaviours of Pb-Ti/MoS_2 composite coatings with the increase of Pb content is in accordance with the variation in H/E ratio that higher H/E is corresponding to the lower wear rate of coating. - Abstract: The lubrication of molybdenum disulfide coatings has commonly been limited by the application environments, for instance, the crystal MoS_2 are easily affected by water to form MoO_3 that causes a higher friction coefficient and short lifetime. Therefore, to improve the tribolgical performance of MoS_2 in high humidity condition, the co-doped Pb-Ti/MoS_2 composite coatings are deposited by unbalanced magnetron sputtering system. The design of the co-doping elements in MoS_2-based coatings can not only maintain the characteristic of low humidity-sensitivity as the Ti/MoS_2 coating but also improve the mechanical properties and tribological performance of coatings as a comparison with single-doped ones. Moreover, the ultra-low friction coefficient with a minimum value of 0.006 under the vacuum condition is achieved for Pb-Ti/MoS_2 composite coating containing about 4.6 at.% Pb, depending on the densification structure of coating. Intriguingly, the wear behaviours of Pb-Ti/MoS_2 composite coatings are in accordance with the variation in H/E (hardness to the elastic modulus) ratio that the coating with higher H/E exhibits lower wear rate. These results demonstrate that the lubricating properties of MoS_2 coatings in both humid environment and vacuum condition can be achieved through the Pb and Ti co-doped, which is of great significant for developing MoS_2 coatings as the environmentally adaptive lubricants.

  1. Evaluation of Stability Parameters in In-Vessel Compositing of Municipal Solid Waste

    Directory of Open Access Journals (Sweden)

    M. M. Amin

    2011-10-01

    Full Text Available Composting is a reliable technology for production of stabilized organic matter that is suitable for agriculture, but this process should be carefully monitored with appropriate indices. Quality of compost is important from maturity and stability viewpoint, but in most compost factories proper attention is not paid to it. This study was designed to evaluate the stability indices in municipal solid waste composting, for selecting the best index in quality monitoring of the wastes. Processed and shredded municipal solid waste from Isfahan compost plant was used as raw material in an in-vessel composting process. A cylindrical reactor with 1 m height and 50 cm diameter made of Pyrex glass was designed. Air was supplied at a specifically flow rate 0.2 L/min.kg to maintain aerobic condition. NH4+/ NO3 ratio, dehydrogenase enzyme activity (DA, pH, oxidation reduction potential (ORP or Eh and specific oxygen uptake rate (SOUR were used as stability indices. These parameters were measured during 40 days of composting process. Changes in these parameters during this period were surveyed and analyzed. Statistical analysis was carried out to choose best of them. Results showed that among the indices, SOUR can show the different stages of microbial decomposition and a numerical value for compost stability also SOUR value less than 2 mg O2/gVS.h can show the full stability of compost.

  2. Piezoelectric Composites by Solid Freeform Fabrication: A Nature-Inspired Approach

    Science.gov (United States)

    Safari, A.; Akdoğan, E. K.

    Piezoelectrics and electrostrictors are indispensable materials for use in transducer technology, as they inherently possess both direct (sensing) and converse (actuation) effects. A piezoelectric/electrostrictive sensor converts a mechanical input (displacement or force) into a measurable electrical output through piezoelectric/electrostrictive energy conversion. In the case of a piezoelectric, an applied mechanical force (stress) induces a voltage across the terminals of the transducer. On the other hand, an applied mechanical force induces a change in the capacitance of an electrostrictive transducer that could be electrically detected. Hence, the mechanical to electrical energy conversion is accomplished directly when a piezoelectric is used, while the same is obtained indirectly if the electroactive material of choice is an electrostrictor. Conversely, both piezoelectric and electrostrictive materials develop an elastic strain under an applied electric field. The said elastic strain is linearly proportional to the applied field in a piezoelectric, whereas electrostrictive coupling involves the second-order (quadratic) coupling of electric field with elastic strain. While piezoelectricity is possible only in noncentrosymetric point groups, electrostriction is observed in all solids, which make it a much more general solid-state phenomenon. Sensing and actuation functions can coexist in a given transducer by the intelligent use of such materials. Piezoelectrics and electrostrictors, therefore, constitute the backbone of modern transducer technology, as mechanical to electric energy (and vice versa) conversion can be accomplished with great efficiency in a way that is second to none among all phenomena known to date [1,2].

  3. Multivariate Quantification of the Solid State Phase Composition of Co-Amorphous Naproxen-Indomethacin

    Directory of Open Access Journals (Sweden)

    Andreas Beyer

    2015-10-01

    Full Text Available To benefit from the optimized dissolution properties of active pharmaceutical ingredients in their amorphous forms, co-amorphisation as a viable tool to stabilize these amorphous phases is of both academic and industrial interest. Reports dealing with the physical stability and recrystallization behavior of co-amorphous systems are however limited to qualitative evaluations based on the corresponding X-ray powder diffractograms. Therefore, the objective of the study was to develop a quantification model based on X-ray powder diffractometry (XRPD, followed by a multivariate partial least squares regression approach that enables the simultaneous determination of up to four solid state fractions: crystalline naproxen, γ-indomethacin, α-indomethacin as well as co-amorphous naproxen-indomethacin. For this purpose, a calibration set that covers the whole range of possible combinations of the four components was prepared and analyzed by XRPD. In order to test the model performances, leave-one-out cross validation was performed and revealed root mean square errors of validation between 3.11% and 3.45% for the crystalline molar fractions and 5.57% for the co-amorphous molar fraction. In summary, even four solid state phases, involving one co-amorphous phase, can be quantified with this XRPD data-based approach.

  4. Mixed solid device based on conducting polymer composite and polymer electrolyte

    Directory of Open Access Journals (Sweden)

    Neves Silmara

    2004-01-01

    Full Text Available Tetraethyl orthosilicate (TEOS derived sol-gel porous films have been utilized as template for the electrochemical polymerization of aniline. Polyaniline-silica composites were obtained and the redox behavior and charge/discharge capacities of a lithium polymeric battery using poly (dimethylsiloxane- co-ethylene oxide as gel polymeric electrolyte, were investigated. The composite presented a high initial capacity (140 mA h g-1 and a reversible capacity of 75 mA h g-1 after 100 charge/discharge cycles. The decrease in the specific capacity was attributed to an increase in charge transfer resistance and a decrease in the diffusion coefficient measured by electrochemical impedance spectroscopy.

  5. Drag and Torque on Locked Screw Propeller

    Directory of Open Access Journals (Sweden)

    Tomasz Tabaczek

    2014-09-01

    Full Text Available Few data on drag and torque on locked propeller towed in water are available in literature. Those data refer to propellers of specific geometry (number of blades, blade area, pitch and skew of blades. The estimation of drag and torque of an arbitrary propeller considered in analysis of ship resistance or propulsion is laborious. The authors collected and reviewed test data available in the literature. Based on collected data there were developed the empirical formulae for estimation of hydrodynamic drag and torque acting on locked screw propeller. Supplementary CFD computations were carried out in order to prove the applicability of the formulae to modern moderately skewed screw propellers.

  6. Multifilamentary superconducting (NbTa)-Sn composite wire by solid-liquid reaction for possible application above 20 tesla

    International Nuclear Information System (INIS)

    Hong, M.; Hull, G.W. Jr.; Fuchs, E.O.; Holthuis, J.T.

    1983-01-01

    Nb alloyed with Ta was employed in fabricating multifilamentary composite wires of (NbTa)-Sn using the liquid-infiltration process. The superconducting A15 phase was formed with subsequent heat treatments at 800-950 0 C by the solid-liquid reaction. High inductive Tsub(c)'s of 18.2 K with sharp transition width ( 4 A/cm 2 at 2O T and 4.2 K were obtained. It was found that 2 wt.% Ta in the Nb was sufficient in the enhancement of the overall Jsub(c) at the high fields and in increasing the Hsub(c2) (4.2 K) to 25 T. (Auth.)

  7. Multifilamentary superconducting (NbTa)-Sn composite wire by solid-liquid reaction for possible application above 20 tesla

    International Nuclear Information System (INIS)

    Hong, M.; Hull, G.W. Jr.; Fuchs, E.O.; Holthuis, J.T.

    1983-01-01

    Nb alloyed with Ta was employed in fabricating multifilamentary composite wires of (NbTa)-Sn using the liquid-infiltration process. The superconducting A15 phase was formed with subsequent heat treatments at 800-950 0 C by the solid-liquid reaction. High inductive Tsub(c)'s of 18.2 K with sharp transition width ( 4 A/cm 2 at 20 T and 4.2 K were obtained. It was found that 2 wt.% Ta in the Nb was sufficient in the enhancement of the overall Jsub(c) at the high fields and in increasing the Hsub(c2) (4.2 K) to 25 T. (orig.)

  8. DC ionic conductivity of NaNO3: γ-Al2O3 composite solid electrolyte system

    International Nuclear Information System (INIS)

    Madhava Rao, M.V.; Narender Reddy, S.; Sadananda Chary, A.

    2005-01-01

    We present DC ionic conductivity measurements on composites formed between Na + ion conductor (NaNO 3 ) and dispersed insulating oxide (alumina). Enhancement of conductivity is noticed to increase with mole percent (m/o) of the dispersoid. The maximum enhancement observed is more than two orders of magnitude with respect to the host material. X-ray diffraction and differential scanning calorimetry studies ruled out the formation of solid solutions between the host material and the dispersoid. The experimental data indicating higher conductivity in dispersed system is interpreted in terms of the formation of space charge layer between the host material and the dispersoid in which defect concentration increases and that is thought to be the possible mechanism of conductivity enhancement. Activation energies obtained from the conductivity data in the extrinsic conduction region indicated least value for the systems at threshold mole percentage

  9. Isotopic measurements (C,N,O) of detonation soot produced from labeled and unlabeled Composition B-3 indicate source of solid carbon residues

    Science.gov (United States)

    Podlesak, David; Manner, Virginia; Amato, Ronald; Dattelbaum, Dana; Gusavsen, Richard; Huber, Rachel

    2017-06-01

    Detonation of HE is an exothermic process whereby metastable complex molecules are converted to simple stable molecules such as H2 O, N2, CO, CO2, and solid carbon. The solid carbon contains various allotropes such as detonation nanodiamonds, graphite, and amorphous carbon. It is well known that certain HE formulations such as Composition B (60% RDX, 40% TNT) produce greater amounts of solid carbon than other more oxygen-balanced formulations. To develop a greater understanding of how formulation and environment influence solid carbon formation, we synthesized TNT and RDX with 13 C and 15 N at levels slightly above natural abundance levels. Synthesized RDX and TNT were mixed at a ratio of 60:40 to form Composition B and solid carbon residues were collected from detonations of isotopically-labeled as well as un-labelled Composition B. The raw HE and detonation residues were analyzed isotopically for C, N, O isotopic compositions. We will discuss differences between treatments groups as a function of formulation and environment. LA-UR - 17-21266.

  10. Solid lipid nanoparticles as attractive drug vehicles: Composition, properties and therapeutic strategies.

    Science.gov (United States)

    Geszke-Moritz, Małgorzata; Moritz, Michał

    2016-11-01

    This work briefly reviews up-to-date developments in solid lipid nanoparticles (SLNs) as effective nanocolloidal system for drug delivery. It summarizes SLNs in terms of their preparation, surface modification and properties. The application of SLNs as a carrier system enables to improve the therapeutic efficacy of drugs from various therapeutic groups. Present uses of SLNs include cancer therapy, dermatology, bacterial infections, brain targeting and eye disorders among others. The usage of SLNs provides enhanced pharmacokinetic properties and modulated release of drugs. SLN ubiquitous application results from their specific features such as possibility of surface modification, increased permeation through biological barriers, resistance to chemical degradation, possibility of co-delivery of various therapeutic agents or stimuli-responsiveness. This paper will be useful to the scientists working in the domain of SLN-based drug delivery systems. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Gradient Meshed and Toughened SOEC (Solid Oxide Electrolyzer Cell) Composite Seal with Self-Healing Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Kathy Lu; W. T. Reynolds, Jr.

    2010-06-08

    High-temperature electrolysis of water steam is a promising approach for hydrogen production. The potential is even more promising when abundant heat source from nuclear power reactors can be efficiently utilized. Hydrogen production through the above approach also allows for low electric consumption. Overall energy conversion efficiencies for high temperature electrolysis are in the 45-50% range compared to ~30% for the conventional electrolysis. Under such motivation, this research is focused on increasing the operation time and high temperature stability of solid oxide electrolyzer cells (SOEC) for splitting water into hydrogen. Specifically, our focus is to improve the SOEC seal thermal stability and performances by alleviating thermal stress and seal cracking issues.

  12. Flexible Black-Phosphorus Nanoflake/Carbon Nanotube Composite Paper for High-Performance All-Solid-State Supercapacitors.

    Science.gov (United States)

    Yang, Bingchao; Hao, Chunxue; Wen, Fusheng; Wang, Bochong; Mu, Congpu; Xiang, Jianyong; Li, Lei; Xu, Bo; Zhao, Zhisheng; Liu, Zhongyuan; Tian, Yongjun

    2017-12-27

    We proposed a simple route for fabrication of the flexible BP nanoflake/carbon nanotube (CNT) composite paper as flexible electrodes in all-solid-state supercapacitors. The highly conductive CNTs not only play a role as active materials but also increase conductivity of the hybrid electrode, enhance electrolyte shuttling and prevent the restacking between BP nanoflakes. The fabricated flexible all-solid-state supercapacitor (ASSP) device at the mass proportion of BP/CNTs 1:4 was found to deliver the highest volumetric capacitance of up to 41.1 F/cm 3 at 0.005 V/s, superior to the ASSP based on the bare graphene or BP. The BP/CNTs (1:4) device delivers a rapid charging/discharging up to 500 V/s, which exhibits the characteristic of a high power density of 821.62 W/cm 3 , while having outstanding mechanical flexibility and high cycling stability over 10 000 cycles (91.5% capacitance retained). Moreover the BP/CNTs (1:4) ASSP device still retains large volumetric capacitance (35.7 F/cm 3 at the scan rate of 0.005 V/s) even after 11 months. In addition, the ASSP of BP/CNTs (1:4) exhibits high energy density of 5.71 mWh/cm 3 and high power density of 821.62 W/cm 3 . As indicated in our work, the strategy of assembling stacked-layer composites films will open up novel possibility for realizing BP and CNTs in new-concept thin-film energy storage devices.

  13. Source emission and model evaluation of formaldehyde from composite and solid wood furniture in a full-scale chamber

    Science.gov (United States)

    Liu, Xiaoyu; Mason, Mark A.; Guo, Zhishi; Krebs, Kenneth A.; Roache, Nancy F.

    2015-12-01

    This paper describes the measurement and model evaluation of formaldehyde source emissions from composite and solid wood furniture in a full-scale chamber at different ventilation rates for up to 4000 h using ASTM D 6670-01 (2007). Tests were performed on four types of furniture constructed of different materials and from different manufacturers. The data were used to evaluate two empirical emission models, i.e., a first-order and power-law decay model. The experimental results showed that some furniture tested in this study, made only of solid wood and with less surface area, had low formaldehyde source emissions. The effect of ventilation rate on formaldehyde emissions was also examined. Model simulation results indicated that the power-law decay model showed better agreement than the first-order decay model for the data collected from the tests, especially for long-term emissions. This research was limited to a laboratory study with only four types of furniture products tested. It was not intended to comprehensively test or compare the large number of furniture products available in the market place. Therefore, care should be taken when applying the test results to real-world scenarios. Also, it was beyond the scope of this study to link the emissions to human exposure and potential health risks.

  14. Solid-state voltammetry-based electrochemical immunosensor for Escherichia coli using graphene oxide-Ag nanoparticle composites as labels.

    Science.gov (United States)

    Jiang, Xiaochun; Chen, Kun; Wang, Jing; Shao, Kang; Fu, Tao; Shao, Feng; Lu, Donglian; Liang, Jiangong; Foda, M Frahat; Han, Heyou

    2013-06-21

    A new electrochemical immunosensor based on solid-state voltammetry was fabricated for the detection of Escherichia coli (E. coli) by using graphene oxide-Ag nanoparticle composites (P-GO-Ag) as labels. To construct the platform, Au nanoparticles (AuNPs) were first self-assembled on an Au electrode surface through cysteamine and served as an effective matrix for antibody (Ab) attachment. Under a sandwich-type immunoassay format, the analyte and the probe (P-GO-Ag-Ab) were successively captured onto the immunosensor. Finally, the bonded AgNPs were detected through a solid-state redox process in 0.2 M of KCl solution. Combining the advantages of the high-loading capability of graphene oxide with promoted electron-transfer rate of AuNPs, this immunosensor produced a 26.92-fold signal enhancement compared with the unamplified protocol. Under the optimal conditions, the immunosensor exhibited a wide linear dependence on the logarithm of the concentration of E. coli ranging from 50 to 1.0 × 10(6) cfu mL(-1) with a detection limit of 10 cfu mL(-1). Moreover, as a practical application, the proposed immunosensor was used to monitor E. coli in lake water with satisfactory results.

  15. Complete doping in solid-state by silica-supported perchloric acid as dopant solid acid: Synthesis and characterization of the novel chiral composite of poly [(±)-2-(sec-butyl) aniline

    Energy Technology Data Exchange (ETDEWEB)

    Farrokhzadeh, Abdolkarim; Modarresi-Alam, Ali Reza, E-mail: modaresi@chem.usb.ac.ir

    2016-05-15

    Poly [(±)-2-(sec-butyl) aniline]/silica-supported perchloric acid composites were synthesized by combination of poly[(±)-2-sec-butylaniline] base (PSBA) and the silica-supported perchloric acid (SSPA) as dopant solid acid in solid-state. The X-ray photoelectron spectroscopy (XPS) and CHNS results confirm nigraniline oxidation state and complete doping for composites (about 75%) and non-complete for the PSBA·HCl salt (about 49%). The conductivity of samples was (≈0.07 S/cm) in agreement with the percent of doping obtained of the XPS analysis. Also, contact resistance was determined by circular-TLM measurement. The morphology of samples by the scanning electron microscopy (SEM) and their coating were investigated by XPS, SEM-map and energy-dispersive X-ray spectroscopy (EDX). The key benefits of this work are the preparation of conductive chiral composite with the delocalized polaron structure under green chemistry and solid-state condition, the improvement of the processability by inclusion of the 2-sec-butyl group and the use of dopant solid acid (SSPA) as dopant. - Highlights: • The solid-state synthesis of the novel chiral composites of poly[(±)-2-(sec-butyl)aniline] (PSBA) and silica-supported perchloric acid (SSPA). • It takes 120 h for complete deprotonation of PSBA.HCl salt. • Use of SSPA as dopant solid acid for the first time to attain the complete doping of PSBA. • The coating of silica surface with PSBA.

  16. Design and numerical investigation of swirl recovery vanes for the Fokker 29 propeller

    Directory of Open Access Journals (Sweden)

    Wang Yangang

    2014-10-01

    Full Text Available Swirl recovery vanes (SRVs are a set of stationary vanes located downstream from a propeller, which may recover some of the residual swirl from the propeller, hoping for an improvement in both thrust and efficiency. The SRV concept design for a scaled version representing the Fokker 29 propeller is performed in this paper, which may give rise to a promotion in propulsive performance of this traditional propeller. Firstly the numerical strategy is validated from two aspects of global quantities and the local flow field of the propeller compared with experimental data, and then the exit flow together with the development of propeller wake is analyzed in detail. Three kinds of SRV are designed with multiple circular airfoils. The numerical results show that the swirl behind the propeller is recovered significantly with Model V3, which is characterized by the highest solidity along spanwise, for various working conditions, and the combination of rotor and vane produced 5.76% extra thrust at the design point. However, a lower efficiency is observed asking for a better vane design and the choice of a working point. The vane position is studied which shows that there is an optimum range for higher thrust and efficiency.

  17. Advanced Booster Composite Case/Polybenzimidazole Nitrile Butadiene Rubber Insulation Development

    Science.gov (United States)

    Gentz, Steve; Taylor, Robert; Nettles, Mindy

    2015-01-01

    The NASA Engineering and Safety Center (NESC) was requested to examine processing sensitivities (e.g., cure temperature control/variance, debonds, density variations) of polybenzimidazole nitrile butadiene rubber (PBI-NBR) insulation, case fiber, and resin systems and to evaluate nondestructive evaluation (NDE) and damage tolerance methods/models required to support human-rated composite motor cases. The proposed use of composite motor cases in Blocks IA and II was expected to increase performance capability through optimizing operating pressure and increasing propellant mass fraction. This assessment was to support the evaluation of risk reduction for large booster component development/fabrication, NDE of low mass-to-strength ratio material structures, and solid booster propellant formulation as requested in the Space Launch System NASA Research Announcement for Advanced Booster Engineering Demonstration and/or Risk Reduction. Composite case materials and high-energy propellants represent an enabling capability in the Agency's ability to provide affordable, high-performing advanced booster concepts. The NESC team was requested to provide an assessment of co- and multiple-cure processing of composite case and PBI-NBR insulation materials and evaluation of high-energy propellant formulations.

  18. Mechanical Properties of Supports and Half‐Cells for Solid Oxide Electrolysis Influenced by Alumina‐Zirconia Composites

    DEFF Research Database (Denmark)

    Charlas, Benoit; Ni, De Wei; Frandsen, Henrik Lund

    2017-01-01

    In order to improve the durability and robustness of solid oxide electrolysis cells (SOEC) and stacks, it is necessary to improve the strength of its components. In cathode supported SOEC, the main structural component is the Ni(O)- YSZ support. But the strength of the half-cell or cell is also...... determined by the strength of other weaker components and by the residual stress state induced by the thermal expansion mismatch. In this study, the mechanical properties of Ni(O)-3YSZ supports with a reference composition and with substitution of 3YSZ by 20A3YSZ (3YSZ with 20 wt.% Al2O3) have been tested...... and compared. The initial interest of this substitution are a decrease of the coefficient of thermal expansion (CTE) mismatch within the half-cell and the fact that 20A3YSZ is stronger than 3YSZ. The influence of the process on the composition, strength, elastic properties and electrical conductivity...

  19. Design and development of solid carbide step drill K34 for machining of CFRP and GFRP composite laminates

    Science.gov (United States)

    Rangaswamy, T.; Nagaraja, R.

    2018-04-01

    The Study focused on design and development of solid carbide step drill K34 to drill holes on composite materials such as Carbon Fiber Reinforced Plastic (CFRP) and Glass Fiber Reinforced Plastic (GFRP). The step drill K34 replaces step wise drilling of diameter 6.5mm and 9 mm holes that reduces the setup time, cutting speed, feed rate cost, delamination and increase the production rate. Several researchers have analyzed the effect of drilling process on various fiber reinforced plastic composites by carrying out using conventional tools and machinery. However, this process operation can lead to different kind of damages such as delamination, fiber pullout, and local cracks. To avoid the problems encountered at the time of drilling, suitable tool material and geometry is essential. This paper deals with the design and development of K34 Carbide step drill used to drill holes on CFRP and GFRP laminates. An Experimental study carried out to investigate the tool geometry, feed rate and cutting speed that avoids delamination and fiber breakage.

  20. Iron oxide functionalized graphene nano-composite for dispersive solid phase extraction of chemical warfare agents from aqueous samples.

    Science.gov (United States)

    Chinthakindi, Sridhar; Purohit, Ajay; Singh, Varoon; Tak, Vijay; Goud, D Raghavender; Dubey, D K; Pardasani, Deepak

    2015-05-15

    Present study deals with the preparation and evaluation of graphene based magnetic nano-composite for dispersive solid phase extraction of Chemical Weapons Convention (CWC) relevant chemicals from aqueous samples. Nano-composite, Fe3O4@SiO2-G was synthesized by covalently bonding silica coated Fe3O4 onto the graphene sheets. Nerve agents (NA), Sulfur mustard (SM) and their non-toxic environmental markers were the target analytes. Extraction parameters like amount of sorbent, extraction time and desorption conditions were optimized. Dispersion of 20 milligram of sorbent in 200mL of water sample for 20min. followed by methanol/chloroform extraction produced average to good recoveries (27-94%) of targeted analytes. Recoveries of real agents exhibited great dependency upon sample pH and ionic strength. Sarin produced maximum recovery under mild acidic conditions (56% at pH 5) while VX demanded alkaline media (83% at pH 9). Salts presence in the aqueous samples was found to be advantageous, raising the recoveries to as high as 94% for SM. Excellent limits of detection (LOD) for sulphur mustard and VX (0.11ngmL(-1) and 0.19ngmL(-1) respectively) proved the utility of the developed method for the off-site analysis of CWC relevant chemicals. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Modeling and Predicting the Electrical Conductivity of Composite Cathode for Solid Oxide Fuel Cell by Using Support Vector Regression

    Science.gov (United States)

    Tang, J. L.; Cai, C. Z.; Xiao, T. T.; Huang, S. J.

    2012-07-01

    The electrical conductivity of solid oxide fuel cell (SOFC) cathode is one of the most important indices affecting the efficiency of SOFC. In order to improve the performance of fuel cell system, it is advantageous to have accurate model with which one can predict the electrical conductivity. In this paper, a model utilizing support vector regression (SVR) approach combined with particle swarm optimization (PSO) algorithm for its parameter optimization was established to modeling and predicting the electrical conductivity of Ba0.5Sr0.5Co0.8Fe0.2 O3-δ-xSm0.5Sr0.5CoO3-δ (BSCF-xSSC) composite cathode under two influence factors, including operating temperature (T) and SSC content (x) in BSCF-xSSC composite cathode. The leave-one-out cross validation (LOOCV) test result by SVR strongly supports that the generalization ability of SVR model is high enough. The absolute percentage error (APE) of 27 samples does not exceed 0.05%. The mean absolute percentage error (MAPE) of all 30 samples is only 0.09% and the correlation coefficient (R2) as high as 0.999. This investigation suggests that the hybrid PSO-SVR approach may be not only a promising and practical methodology to simulate the properties of fuel cell system, but also a powerful tool to be used for optimal designing or controlling the operating process of a SOFC system.

  2. The Development of Nano-Composite Electrodes for Solid Oxide Electrolyzers

    Energy Technology Data Exchange (ETDEWEB)

    Gorte, Raymond J.; Vohs, John M.

    2014-03-26

    Solid oxide fuel cells (SOFC) and electrolyzers (SOE) offer an attractive means for converting between electrical and chemical energy. Because they operate at high temperatures and are usually based on electrolytes that are oxygen-ion conducting ceramics, such as yttria-stabilized zirconia (YSZ), they are equally capable of converting between CO and CO2 as between H2 and H2O. When operated in the SOFC mode, they are able to operate on hydrocarbon fuels so long as there are no materials within the anode that can catalyze carbon formation. Compared to other types of electrolyzers, SOE can exhibit the highest efficiencies because the theoretical Nernst potential is lower at high temperatures and because the electrode overpotentials in SOE tend to be much lower. Finally, pure H2 can be produced without an external electrical source by electrolysis of steam at one electrode and oxidation of any fuel at the other electrode through a process known as Natural-Gas Assisted Steam Electrolysis. This final report describes results from studies of novel electrodes for SOE and SOFC prepared by infiltration methods.

  3. Liquid versus solid energy intake in relation to body composition among Australian children

    DEFF Research Database (Denmark)

    Zheng, M; Allman-Farinelli, M; Heitmann, B L

    2014-01-01

    intake (1 MJ day(-1) ) was more closely associated with both △BMIz8-11.5y (β = 0.23, P = 0.02) and %BF11.5y (β = 2.31%, P = 0.01) than solid energy intake (△BMIz8-11.5y: β = 0.12, P = 0.01 and %BF11.5y : β = 0.80%, P = 0.07). SSB consumption (100 g day(-1) ) was directly associated with △BMIz8-11.5y (β...... = 0.08, P = 0.02) and %BF11.5y (β = 0.92%, P = 0.004),whereas diet drinks (100 g day(-1) ) were inversely associated with △BMIz8-11.5y (β = 0.18, P = 0.02). Substitution of 100 g of SSB by 100 g of water or diet drink, but not other beverages, was inversely associated with both △BMIz8-11.5y and %BF11.......5y (P water can have long-term beneficial effects on childhood adiposity....

  4. Experimental research on air propellers

    Science.gov (United States)

    Durand, William F

    1918-01-01

    The purposes of the experimental investigation on the performance of air propellers described in this report are as follows: (1) the development of a series of design factors and coefficients drawn from model forms distributed with some regularity over the field of air-propeller design and intended to furnish a basis of check with similar work done in other aerodynamic laboratories, and as a point of departure for the further study of special or individual types and forms; (2) the establishment of a series of experimental values derived from models and intended for later use as a basis for comparison with similar results drawn from certain selected full-sized forms and tested in free flight.

  5. Analysis of physical composition and heavy metals pollution of municipal solid waste (MSW) in Beijing

    Science.gov (United States)

    Zhang, H. B.; Zhang, H. Y.; Wang, G. Q.; Bai, X. J.

    2018-03-01

    By using on-site sampling and physical-chemical analysis, the physical composition and the contents of heavy metals in Beijing MSW were researched. The result showed that the main components of MSW in Beijing are mainly kitchen waste, the average content of kitchen waste are more than 60% and 50% in summer and in winter, respectively. The pollution of Cu, Hg and Cr are all more serious for MSW in Haidian and Dongcheng district. The heavy metal pollution of MSW in summer is higher than that in winter in Beijing. Seasonal impacts should be taken into consideration when dealing with MSW. The content of heavy metals in MSW exceeded the background value of soil in Haidian and Dongcheng districts. In order to reduce heavy metal pollution, the MSW should be separated collection and treated.

  6. Composition, Production Rate and Management of Dental Solid Waste in 2017 in Birjand, Iran

    Directory of Open Access Journals (Sweden)

    Habibe Momeni

    2018-01-01

    Full Text Available Background: The presence of toxic and pathogenic agents in the dental waste products has made it to be classified as “hazardous waste.” Objective: To assess dental waste production rate and composition and approaches used to manage these waste products in 2017 in Birjand, Iran. Methods: 48 dental clinics were evaluated in two months of 2017. Sampling was performed from each clinic 3 times a week. Samples were manually divided into 5 categories of chemical-pharmaceutical, infectious, semi-household, sharp and cutting materials, and toxic waste products, and weighed. A checklist containing 25 questions was used to evaluate the aspects of waste management in dental clinics. Results: The total amount of waste products generated in dental clinics was 7848.02 kg/ year in which semi-household waste had the highest quantity (4263.411 kg/year and toxic waste had the lowest quantity (9.275 kg/year. Components with the highest amounts in dentistry waste products were nylon gloves (16.7%, paper and cardboard (13.4%, latex gloves (10.8%, and pharmaceuticals (10.2%. Waste separation was restricted to sharp and cutting waste. More than half (57% of dental units were equipped with amalgam filter. Fixing solutions were directly discharged to sewage in 48.6% of clinics. There was no program to reduce waste generation in 54% of the clinics. Autoclave was the main tool for sterilizing dental instruments. Conclusion: This study showed a remarkable share of recyclable materials in the composition of dental waste and lack of special approach to manage waste in dental clinics. It is necessary to plan for minimizing generation of, separating, and recycling waste at source.

  7. Composition, Production Rate and Management of Dental Solid Waste in 2017 in Birjand, Iran.

    Science.gov (United States)

    Momeni, Habibe; Tabatabaei Fard, Seyyedeh Fatemeh; Arefinejad, Aliye; Afzali, Afsane; Talebi, Farkhonde; Rahmanpour Salmani, Elham

    2018-01-01

    The presence of toxic and pathogenic agents in the dental waste products has made it to be classified as "hazardous waste." To assess dental waste production rate and composition and approaches used to manage these waste products in 2017 in Birjand, Iran. 48 dental clinics were evaluated in two months of 2017. Sampling was performed from each clinic 3 times a week. Samples were manually divided into 5 categories of chemical-pharmaceutical, infectious, semi-household, sharp and cutting materials, and toxic waste products, and weighed. A checklist containing 25 questions was used to evaluate the aspects of waste management in dental clinics. The total amount of waste products generated in dental clinics was 7848.02 kg/ year in which semi-household waste had the highest quantity (4263.411 kg/year) and toxic waste had the lowest quantity (9.275 kg/year). Components with the highest amounts in dentistry waste products were nylon gloves (16.7%), paper and cardboard (13.4%), latex gloves (10.8%), and pharmaceuticals (10.2%). Waste separation was restricted to sharp and cutting waste. More than half (57%) of dental units were equipped with amalgam filter. Fixing solutions were directly discharged to sewage in 48.6% of clinics. There was no program to reduce waste generation in 54% of the clinics. Autoclave was the main tool for sterilizing dental instruments. This study showed a remarkable share of recyclable materials in the composition of dental waste and lack of special approach to manage waste in dental clinics. It is necessary to plan for minimizing generation of, separating, and recycling waste at source.

  8. The composition, heating value and renewable share of the energy content of mixed municipal solid waste in Finland

    International Nuclear Information System (INIS)

    Horttanainen, M.; Teirasvuo, N.; Kapustina, V.; Hupponen, M.; Luoranen, M.

    2013-01-01

    Highlights: • New experimental data of mixed MSW properties in a Finnish case region. • The share of renewable energy of mixed MSW. • The results were compared with earlier international studies. • The average share of renewable energy was 30% and the average LHVar 19 MJ/kg. • Well operating source separation decreases the renewable energy content of MSW. - Abstract: For the estimation of greenhouse gas emissions from waste incineration it is essential to know the share of the renewable energy content of the combusted waste. The composition and heating value information is generally available, but the renewable energy share or heating values of different fractions of waste have rarely been determined. In this study, data from Finnish studies concerning the composition and energy content of mixed MSW were collected, new experimental data on the compositions, heating values and renewable share of energy were presented and the results were compared to the estimations concluded from earlier international studies. In the town of Lappeenranta in south-eastern Finland, the share of renewable energy ranged between 25% and 34% in the energy content tests implemented for two sample trucks. The heating values of the waste and fractions of plastic waste were high in the samples compared to the earlier studies in Finland. These high values were caused by good source separation and led to a low share of renewable energy content in the waste. The results showed that in mixed municipal solid waste the renewable share of the energy content can be significantly lower than the general assumptions (50–60%) when the source separation of organic waste, paper and cardboard is carried out successfully. The number of samples was however small for making extensive conclusions on the results concerning the heating values and renewable share of energy and additional research is needed for this purpose

  9. The composition, heating value and renewable share of the energy content of mixed municipal solid waste in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Horttanainen, M., E-mail: mika.horttanainen@lut.fi; Teirasvuo, N.; Kapustina, V.; Hupponen, M.; Luoranen, M.

    2013-12-15

    Highlights: • New experimental data of mixed MSW properties in a Finnish case region. • The share of renewable energy of mixed MSW. • The results were compared with earlier international studies. • The average share of renewable energy was 30% and the average LHVar 19 MJ/kg. • Well operating source separation decreases the renewable energy content of MSW. - Abstract: For the estimation of greenhouse gas emissions from waste incineration it is essential to know the share of the renewable energy content of the combusted waste. The composition and heating value information is generally available, but the renewable energy share or heating values of different fractions of waste have rarely been determined. In this study, data from Finnish studies concerning the composition and energy content of mixed MSW were collected, new experimental data on the compositions, heating values and renewable share of energy were presented and the results were compared to the estimations concluded from earlier international studies. In the town of Lappeenranta in south-eastern Finland, the share of renewable energy ranged between 25% and 34% in the energy content tests implemented for two sample trucks. The heating values of the waste and fractions of plastic waste were high in the samples compared to the earlier studies in Finland. These high values were caused by good source separation and led to a low share of renewable energy content in the waste. The results showed that in mixed municipal solid waste the renewable share of the energy content can be significantly lower than the general assumptions (50–60%) when the source separation of organic waste, paper and cardboard is carried out successfully. The number of samples was however small for making extensive conclusions on the results concerning the heating values and renewable share of energy and additional research is needed for this purpose.

  10. Low-Cost Propellant Launch From a Tethered Balloon

    Science.gov (United States)

    Wilcox, Brian

    2006-01-01

    A document presents a concept for relatively inexpensive delivery of propellant to a large fuel depot in low orbit around the Earth, for use in rockets destined for higher orbits, the Moon, and for remote planets. The propellant is expected to be at least 85 percent of the mass needed in low Earth orbit to support the NASA Exploration Vision. The concept calls for the use of many small ( 10 ton) spin-stabilized, multistage, solid-fuel rockets to each deliver 250 kg of propellant. Each rocket would be winched up to a balloon tethered above most of the atmospheric mass (optimal altitude 26 2 km). There, the rocket would be aimed slightly above the horizon, spun, dropped, and fired at a time chosen so that the rocket would arrive in orbit near the depot. Small thrusters on the payload (powered, for example, by boil-off gases from cryogenic propellants that make up the payload) would precess the spinning rocket, using data from a low-cost inertial sensor to correct for small aerodynamic and solid rocket nozzle misalignment torques on the spinning rocket; would manage the angle of attack and the final orbit insertion burn; and would be fired on command from the depot in response to observations of the trajectory of the payload so as to make small corrections to bring the payload into a rendezvous orbit and despin it for capture by the depot. The system is low-cost because the small rockets can be mass-produced using the same techniques as those to produce automobiles and low-cost munitions, and one or more can be launched from a U.S. territory on the equator (Baker or Jarvis Islands in the mid-Pacific) to the fuel depot on each orbit (every 90 minutes, e.g., any multiple of 6,000 per year).

  11. A Study of Interaction of Laser Light with Small Drops of XM46 Propellant and Related Liquids

    National Research Council Canada - National Science Library

    Juvan, Kim

    1999-01-01

    Stimulated Raman spectroscopy (SRS) has been explored as a possible diagnostic tool to determine if observable changes in composition occur in the liquid gun propellants containing hydroxyl ammonium nitrate (HAN...

  12. Sample preparation composite and replicate strategy for assay of solid oral drug products.

    Science.gov (United States)

    Harrington, Brent; Nickerson, Beverly; Guo, Michele Xuemei; Barber, Marc; Giamalva, David; Lee, Carlos; Scrivens, Garry

    2014-12-16

    In pharmaceutical analysis, the results of drug product assay testing are used to make decisions regarding the quality, efficacy, and stability of the drug product. In order to make sound risk-based decisions concerning drug product potency, an understanding of the uncertainty of the reportable assay value is required. Utilizing the most restrictive criteria in current regulatory documentation, a maximum variability attributed to method repeatability is defined for a drug product potency assay. A sampling strategy that reduces the repeatability component of the assay variability below this predefined maximum is demonstrated. The sampling strategy consists of determining the number of dosage units (k) to be prepared in a composite sample of which there may be a number of equivalent replicate (r) sample preparations. The variability, as measured by the standard error (SE), of a potency assay consists of several sources such as sample preparation and dosage unit variability. A sampling scheme that increases the number of sample preparations (r) and/or number of dosage units (k) per sample preparation will reduce the assay variability and thus decrease the uncertainty around decisions made concerning the potency of the drug product. A maximum allowable repeatability component of the standard error (SE) for the potency assay is derived using material in current regulatory documents. A table of solutions for the number of dosage units per sample preparation (r) and number of replicate sample preparations (k) is presented for any ratio of sample preparation and dosage unit variability.

  13. Low energy ion scattering (LEIS) and the compositional and structural analysis of solid surfaces

    International Nuclear Information System (INIS)

    Berg, J.A. van den; Armour, D.G.

    1981-01-01

    The physics of Low Energy Ion Scattering (LEIS) and its application as a surface analytical technique are reviewed. It is shown that compositional and short-range structural information can be obtained by choosing experimental conditions which optimize the contributions of single and double (or multiple) collisions, respectively. The LEIS technique allows mass analysis in a straightforward way, possesses a high surface selectivity but is unable to provide quantitative information in isolation due to scattering cross-section uncertainties and not easily quantifiable charge exchange effects. Structural information regarding adsorbate positions on single crystal surfaces and the short-range substrate structure (including damaged and reconstructed surfaces) can be obtained by exploiting shadowing and/or multiple scattering phenomena. The progress made in recent years in this area is charted. It is shown that computer simulations often play an important role in this type of study. Effects, such as charge exchange, inelastic energy loss and ion beam surface perturbations, which complicate the use of low energy ion scattering for surface analysis are discussed in detail. The present status of the technique in the different areas of study is indicated. (author)

  14. The production of hydroxyapatite prototypes from solid bodies of Gypsum/Polyvinyl Alcohol composites

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Amanda Alves; Ferraz, Andrea de Vasconcelos; Dantas, Alan Christie; Olivier, Nelson Cardenas, E-mail: andrea.ferraz@univasf.edu.br [Universidade Federal do Vale do Sao Francisco (UNIVASF), Juazeiro, BA (Brazil)

    2014-08-15

    Prototypes of porous hydroxyapatite (HAp) were produced from Gypsum/PVA composite, using a mass proportion of 15% polymer. The material was obtained by means of chemical conversion in (NH{sub 4}){sub 2}HPO{sub 4} 0.5 mol.L{sup -1} solution and NH{sub 4}OH 6.0 mol.L{sup -1} alkaline medium for pH control, maintained between 6.0 and 9.0. The reaction occurred at a temperature of 100°C at different test times. The obtained HAp was characterized by several techniques, such as FTIR, which identified the SO{sub 4}{sup 2-} groups characteristic for the Gypsum block, and the PO{sub 4}{sup 2-} groups that are attributed to the biomaterial HAp, besides XRD and SEM, which made it possible to confirm a successful conversion of the material. Tests for mechanical resistance to compression (σ{sub c}) were carried out for both materials as well. (author)

  15. The Systematics of Activity-Composition Relations in Mg-Fe2+ Oxide and Silicate Solid Solutions

    Science.gov (United States)

    O'Neill, H. S.

    2006-12-01

    The need to quantify activity-composition relations of mineral solid solutions for petrologic modelling has prompted many experimental studies, but different studies on the same system often appear to show a startling lack of consistency. A good example is Mg-Fe2+ mixing in garnet (the pyrope-almandine join). This is understandable because the energies of mixing in solid solutions are often obtained experimentally as small difference between large numbers. In particular, the fallacy of using a sequential approach to data fitting to a thermodynamic model leads to the accumulated errors being artificially concentrated onto the last step of the fitting process, which is usually that part of the model dealing with the excess energies of mixing. This gives rise to erroneous activity-composition relations, often apparently showing complex deviations from ideality. Systemizing the results of many studies can reveal underlying patterns of behaviour while also identifying outliers and anomalies that may be worth reinvestigating. Davies and Navrotsky [1] showed that the energies of mixing of many different pairs of ions with the same charge correlated well with the difference in molar volumes of the end-members, within a particular crystal structure. This empirical work is now supported by theoretical calculations. It underlies the modern approach to melt/crystal trace-element partitioning. Provided an internally consistent dataset is used, an analogous correlation may be demonstrated across different crystal structures for the mixing of one pair of ions, such as Mg and Fe2+. Activity-composition relations in MgO-"FeO" magnesiowuestite solutions in equilibrium with iron metal were used to obtain the properties of Mg-Fe olivine solutions from magnesiowuestite/olivine partitioning [2]. New results at 1400 K, 1 bar and 1473 K, 25 kb (O'Neill and Pownceby, in prep.) confirm previous work that mixing in Mg-Fe olivine is regular (symmetrical) with W Mg-Fe = 2.5 kJ/mol, with an

  16. Rocket propellants with reduced smoke and high burning rates

    Energy Technology Data Exchange (ETDEWEB)

    Menke, K.; Eisele, S. [Fraunhofer-Institut fuer Chemische Technologie (ICT), Pfinztal-Berghausen (Germany)

    1997-07-01

    Rocket propellants with reduced smoke and high burning rates recommend themselves for use in a rocket motor for high accelerating tactical missiles. They serve for an improved camouflage on the battle field and may enable guidance control due to the higher transmission of their rocket plume compared to traditional aluminized composite propellants. In this contribution the material based ranges of performance and properties of three non aluminized rocket propellants will be introduced and compared to each other. The selected formulations based on AP/HTPB; AP/PU/TMETN and AP/HMX/GAP/TMETN have roughly the same specific impulse of I{sub SP}=2430 Ns/kg at 70:1 expansion ratio. The burning rates in the pressure range from 10-18 MPa vary from to 26-33 mm/s for the AP/HTPB propellant, 52-68 mm/s for the formulation based on AP/PU/TMETN and 28-39 mm/s for the propellant based on AP/HMX/GAP. With 58% and 20% AP-contents the propellants with nitrate ester plasticizers create a much smaller secondary signature than the AP/HTPB representative containing 85% AP. Their disadvantage, however, is the connection of high performance to a high level of energetic plasticizer. For this reason, the very fast burning propellant based on AP/PU/TMETN is endowed with a low elastic modulus and is limited to a grain configuration which isn`t exposed too much to the fast and turbulent airstream. The mechanical properties of the AP/HMX/GAP-propellant are as good or better as those of the AP/HTPB propellant. The first one exhibits the same performance and burn rates as the composite representative but produces only one fifth of HCl exhaust. For this reason it is recommended for missile applications, which must have high accelerating power together with a significantly reduced plume signature and smoke production. (orig.) [Deutsch] Rauchreduzierte Festtreibstoffe mit hohen Abbrandgeschwindigkeiten bieten sich fuer den Antrieb hochbeschleunigender taktischer Flugkoerper an, da sie gegenueber

  17. Influence of load and sliding velocity on wear resistance of solid-lubricant composites of ultra-high molecular weight polyethylene

    Science.gov (United States)

    Panin, S. V.; Kornienko, L. A.; Buslovich, D. G.; Alexenko, V. O.; Ivanova, L. R.

    2017-12-01

    To determine the limits of the operation loading intervals appropriate for the use of solid lubricant UHMWPE composites in tribounits for mechanical engineering and medicine, the tribotechnical properties of UHMWPE blends with the optimum solid lubricant filler content (polytetrafluoroethylene, calcium stearate, molybdenum disulfide, colloidal graphite, boron nitride) are studied under dry sliding friction at different velocities (V = 0.3 and 0.5 m/s) and loads (P = 60 and 140 N). It is shown that the wear resistance of solid lubricant UHMWPE composites at moderate sliding velocities (V = 0.3 m/s) and loads (P = 60 N) increases 2-3 times in comparison with pure UHMWPE, while at high load P = 140 N wear resistance of both neat UHMWPE and its composites is reduced almost twice. At high sliding velocities and loads (up to P = 140 N), multiple increasing of the wear of pure UHMWPE and its composites takes place (by the factor of 5 to 10). The operational conditions of UHMWPE composites in tribounits in engineering and medicine are discussed.

  18. Processing and characterization of solid and microcellular biobased and biodegradable PHBV-based polymer blends and composites

    Science.gov (United States)

    Javadi, Alireza

    will not only reduce cost but also improve processability due to the use of supercritical fluid. Various material properties of the solid (without the foaming agent) and microcellular components (with foaming agent) made of PHBV-based polymer blends or composites were investigated including static mechanical properties (tensile testing), dynamic mechanical properties (dynamic mechanical analysis), thermal properties (differential scanning calorimetry and thermo gravimetric analysis), crystallinity(wide angle X-ray scattering analysis), and morphology (scanning electron microscopy and transmission electron microscopy). The composition-processing-structure-property relationship of these solid and microcellular components were established.

  19. Quantification and chemical composition of mixed bacteria harvested from solid fractions of rumen digesta: Effects of detachment procedure

    International Nuclear Information System (INIS)

    Martin-Orue, S.M.; Balcells, J.; Zakraoui, F.; Castrillo, C.

    1999-01-01

    Four ewes were given two diets made up with two ratios of rolled barley grain and ammonia treated straw (80/20, diet C and 20/80, diet R). The animals were fed twice a day. Two microbial markers, purine bases (PB) and 15 N, were used as internal and external markers, respectively. Ruminal bacteria from the liquid (LAB) and solid (SAB) fractions of digesta were harvested from samples obtained at 1 and 6 h after feeding. Bacteria were separated from the particulate material by cooling plus homogenisation (B), by applying tertiary butanol (TB) or methylcellulose (M), or by changes of temperature (CHT). The most effective procedures to remove bacteria from the solid phase were M and CHT treatments. CHT, however, showed the highest level of losses and the lowest total recovery of the bacterial pellet. There were no differences between B and TB treatments in either detaching efficiency or total recovery ratio of adherent bacteria. Ratio of recovery of detached material as a bacterial pellet was 32.0, 32.2, 33.3 and 27.8% for B, TB, M and CHT treatments, respectively. Diet did not interact with detaching efficiency of the experimental treatments although concentration of total N (g/100g OM) and PB (μmol/g OM) were higher in pellets obtained with diet C (9.11 and 125) than with diet R (8.20 and 107), respectively (P < 0.05). Postpandrial differences were not significant. Bacterial samples extracted from the liquid phase contained significantly (P < 0.001) more total N (9.21 vs 8.51), PB (160.5 vs 104.3) and PB/N (1.73 vs 1.23 μmol/mg) than those samples extracted from the solid phase. There were no differences in the chemical composition of the microbial sample after detachment by B, TB and M treatments but the bacterial extract obtained after CHT treatment showed significant changes in PB, N content and PB/N ratio (P < 0.01). (author)

  20. Quantification and chemical composition of mixed bacteria harvested from solid fractions of rumen digesta: Effects of detachment procedure

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Orue, S M; Balcells, J; Zakraoui, F; Castrillo, C [Departamento de Produccion Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Zaragoza (Spain)

    1999-06-01

    Four ewes were given two diets made up with two ratios of rolled barley grain and ammonia treated straw (80/20, diet C and 20/80, diet R). The animals were fed twice a day. Two microbial markers, purine bases (PB) and {sup 15}N, were used as internal and external markers, respectively. Ruminal bacteria from the liquid (LAB) and solid (SAB) fractions of digesta were harvested from samples obtained at 1 and 6 h after feeding. Bacteria were separated from the particulate material by cooling plus homogenisation (B), by applying tertiary butanol (TB) or methylcellulose (M), or by changes of temperature (CHT). The most effective procedures to remove bacteria from the solid phase were M and CHT treatments. CHT, however, showed the highest level of losses and the lowest total recovery of the bacterial pellet. There were no differences between B and TB treatments in either detaching efficiency or total recovery ratio of adherent bacteria. Ratio of recovery of detached material as a bacterial pellet was 32.0, 32.2, 33.3 and 27.8% for B, TB, M and CHT treatments, respectively. Diet did not interact with detaching efficiency of the experimental treatments although concentration of total N (g/100g OM) and PB ({mu}mol/g OM) were higher in pellets obtained with diet C (9.11 and 125) than with diet R (8.20 and 107), respectively (P < 0.05). Postpandrial differences were not significant. Bacterial samples extracted from the liquid phase contained significantly (P < 0.001) more total N (9.21 vs 8.51), PB (160.5 vs 104.3) and PB/N (1.73 vs 1.23 {mu}mol/mg) than those samples extracted from the solid phase. There were no differences in the chemical composition of the microbial sample after detachment by B, TB and M treatments but the bacterial extract obtained after CHT treatment showed significant changes in PB, N content and PB/N ratio (P < 0.01). (author) 38 refs, 2 figs, 4 tabs

  1. A theoretical and experimental investigation of propeller performance methodologies

    Science.gov (United States)

    Korkan, K. D.; Gregorek, G. M.; Mikkelson, D. C.

    1980-01-01

    This paper briefly covers aspects related to propeller performance by means of a review of propeller methodologies; presentation of wind tunnel propeller performance data taken in the NASA Lewis Research Center 10 x 10 wind tunnel; discussion of the predominent limitations of existing propeller performance methodologies; and a brief review of airfoil developments appropriate for propeller applications.

  2. Effects of chemical composition of fly ash on efficiency of metal separation in ash-melting of municipal solid waste

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Takashi, E-mail: t-okada@u-fukui.ac.jp [Laboratory of Solid Waste Disposal Engineering, Graduate School of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628 (Japan); Tomikawa, Hiroki [Laboratory of Solid Waste Disposal Engineering, Graduate School of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628 (Japan)

    2013-03-15

    Highlights: ► Separation of Pb and Zn from Fe and Cu in ash-melting of municipal solid waste. ► Molar ratio of Cl to Na and K in fly ash affected the metal-separation efficiency. ► The low molar ratio and a non-oxidative atmosphere were better for the separation. - Abstract: In the process of metal separation by ash-melting, Fe and Cu in the incineration residue remain in the melting furnace as molten metal, whereas Pb and Zn in the residue are volatilized. This study investigated the effects of the chemical composition of incineration fly ash on the metal-separation efficiency of the ash-melting process. Incineration fly ash with different chemical compositions was melted with bottom ash in a lab-scale reactor, and the efficiency with which Pb and Zn were volatilized preventing the volatilization of Fe and Cu was evaluated. In addition, the behavior of these metals was simulated by thermodynamic equilibrium calculations. Depending on the exhaust gas treatment system used in the incinerator, the relationships among Na, K, and Cl concentrations in the incineration fly ash differed, which affected the efficiency of the metal separation. The amounts of Fe and Cu volatilized decreased by the decrease in the molar ratio of Cl to Na and K in the ash, promoting metal separation. The thermodynamic simulation predicted that the chlorination volatilization of Fe and Cu was prevented by the decrease in the molar ratio, as mentioned before. By melting incineration fly ash with the low molar ratio in a non-oxidative atmosphere, most of the Pb and Zn in the ash were volatilized leaving behind Fe and Cu.

  3. The influence of the choice of propeller design tool on propeller performance

    OpenAIRE

    Skåland, Edvard Knutsen

    2016-01-01

    In this master thesis different propeller design and analysis methods are presented and compared in terms of the accuracy and computational efficiency of their theory. These methods include lifting line, vortex lattice lifting surface and panel methods. A propeller design program based on lifting line theory was developed by the author. This program has been used together with the propeller design programs OpenProp and AKPD to make six propeller designs. The designs are based o...

  4. Study of Liquid Breakup Process in Solid Rocket Motor Nozzle

    Science.gov (United States)

    2016-02-16

    Laboratory, Edwards, CA Abstract In a solid rocket motor (SRM), when the aluminum based propellant combusts, the fuel is oxidized into alumina (Al2O3...34Chemical Erosion of Refractory-Metal Nozzle Inserts in Solid - Propellant Rocket Motors," J. Propulsion and Power, Vol. 25, no.1,, 2009. [4] E. Y. Wong...34 Solid Rocket Nozzle Design Summary," in 4th AIAA Propulsion Joint Specialist Conference, Cleveland, OH, 1968. [5] Nayfeh, A. H.; Saric, W. S

  5. Propeller Test Facilities Â

    Data.gov (United States)

    Federal Laboratory Consortium — Description: Three electrically driven whirl test stands are used to determine propeller (or other rotating device) performance at various rotational speeds. These...

  6. Crystallinity and compositional changes in carbonated apatites: Evidence from 31P solid-state NMR, Raman, and AFM analysis

    Science.gov (United States)

    McElderry, John-David P.; Zhu, Peizhi; Mroue, Kamal H.; Xu, Jiadi; Pavan, Barbara; Fang, Ming; Zhao, Guisheng; McNerny, Erin; Kohn, David H.; Franceschi, Renny T.; Holl, Mark M. Banaszak; Tecklenburg, Mary M. J.; Ramamoorthy, Ayyalusamy; Morris, Michael D.

    2013-10-01

    Solid-state (magic-angle spinning) NMR spectroscopy is a useful tool for obtaining structural information on bone organic and mineral components and synthetic model minerals at the atomic-level. Raman and 31P NMR spectral parameters were investigated in a series of synthetic B-type carbonated apatites (CAps). Inverse 31P NMR linewidth and inverse Raman PO43-ν1 bandwidth were both correlated with powder XRD c-axis crystallinity over the 0.3-10.3 wt% CO32- range investigated. Comparison with bone powder crystallinities showed agreement with values predicted by NMR and Raman calibration curves. Carbonate content was divided into two domains by the 31P NMR chemical shift frequency and the Raman phosphate ν1 band position. These parameters remain stable except for an abrupt transition at 6.5 wt% carbonate, a composition which corresponds to an average of one carbonate per unit cell. This near-binary distribution of spectroscopic properties was also found in AFM-measured particle sizes and Ca/P molar ratios by elemental analysis. We propose that this transition differentiates between two charge-balancing ion-loss mechanisms as measured by Ca/P ratios. These results define a criterion for spectroscopic characterization of B-type carbonate substitution in apatitic minerals.

  7. Morphology, composition, and mixing state of primary particles from combustion sources - crop residue, wood, and solid waste.

    Science.gov (United States)

    Liu, Lei; Kong, Shaofei; Zhang, Yinxiao; Wang, Yuanyuan; Xu, Liang; Yan, Qin; Lingaswamy, A P; Shi, Zongbo; Lv, Senlin; Niu, Hongya; Shao, Longyi; Hu, Min; Zhang, Daizhou; Chen, Jianmin; Zhang, Xiaoye; Li, Weijun

    2017-07-11

    Morphology, composition, and mixing state of individual particles emitted from crop residue, wood, and solid waste combustion in a residential stove were analyzed using transmission electron microscopy (TEM). Our study showed that particles from crop residue and apple wood combustion were mainly organic matter (OM) in smoldering phase, whereas soot-OM internally mixed with K in flaming phase. Wild grass combustion in flaming phase released some Cl-rich-OM/soot particles and cardboard combustion released OM and S-rich particles. Interestingly, particles from hardwood (pear wood and bamboo) and softwood (cypress and pine wood) combustion were mainly soot and OM in the flaming phase, respectively. The combustion of foam boxes, rubber tires, and plastic bottles/bags in the flaming phase released large amounts of soot internally mixed with a small amount of OM, whereas the combustion of printed circuit boards and copper-core cables emitted large amounts of OM with Br-rich inclusions. In addition, the printed circuit board combustion released toxic metals containing Pb, Zn, Sn, and Sb. The results are important to document properties of primary particles from combustion sources, which can be used to trace the sources of ambient particles and to know their potential impacts in human health and radiative forcing in the air.

  8. Optimization of the Büchi B-90 spray drying process using central composite design for preparation of solid dispersions.

    Science.gov (United States)

    Gu, Bing; Linehan, Brian; Tseng, Yin-Chao

    2015-08-01

    A central composite design approach was applied to study the effect of polymer concentration, inlet temperature and air flow rate on the spray drying process of the Büchi B-90 nano spray dryer (B-90). Hypromellose acetate succinate-LF was used for the Design of Experiment (DoE) study. Statistically significant models to predict the yield, spray rate, and drying efficiency were generated from the study. The spray drying conditions were optimized according to the models to maximize the yield and efficiency of the process. The models were further validated using a poorly water-soluble investigational compound (BI064) from Boehringer Ingelheim Pharmaceuticals. The polymer/drug ratio ranged from 1/1 to 3/1w/w. The spray dried formulations were amorphous determined by differential scanning calorimetry and X-ray powder diffraction. The particle size of the spray dried formulations was 2-10 μm under polarized light microscopy. All the formulations were physically stable for at least 3h when suspended in an aqueous vehicle composed of 1% methyl cellulose. This study demonstrates that DoE is a useful tool to optimize the spray drying process, and the B-90 can be used to efficiently produce amorphous solid dispersions with a limited quantity of drug substance available during drug discovery stages. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Regression models of ultimate methane yields of fruits and vegetable solid wastes, sorghum and napiergrass on chemical composition

    Energy Technology Data Exchange (ETDEWEB)

    Gunaseelan, V.N. [PSG College of Arts and Science, Coimbatore (India). Department of Zoology

    2007-04-15

    Several fractions of fruits and vegetable solid wastes (FVSW), sorghum and napiergrass were analyzed for total solids (TS), volatile solids (VS), total organic carbon, total kjeldahl nitrogen, total soluble carbohydrate, extractable protein, acid-detergent fiber (ADF), lignin, cellulose and ash contents. Their ultimate methane yields (B{sub o}) were determined using the biochemical methane potential (BMP) assay. A series of simple and multiple regression models relating the B{sub o} to the various substrate constituents were generated and evaluated using computer statistical software, Statistical Package for Social Sciences (SPSS). The results of simple regression analyses revealed that, only weak relationship existed between the individual components such as carbohydrate, protein, ADF, lignin and cellulose versus B{sub o}. A regression of B{sub o} versus combination of two variables as a single independent variable such as carbohydrate/ADF and carbohydrate + protein/ADF also showed that the relationship is not strong. Thus it does not appear possible to relate the B{sub o} of FVSW, sorghum and napiergrass with single compositional characteristics. The results of multiple regression analyses showed promise and the relationship appeared to be good. When ADF and lignin/ADF were used as independent variables, the percentage of variation accounted for by the model is low for FVSW (r{sup 2}=0.665) and sorghum and napiergrass (r{sup 2}=0.746). Addition of nitrogen, ash and total soluble carbohydrate data to the model had a significantly higher effect on prediction of B{sub o} of these wastes with the r{sup 2} values ranging from 0.9 to 0.99. More than 90% of variation in B{sub o} of FVSW could be accounted for by the models when the variables carbohydrate, lignin, lignin/ADF, nitrogen and ash (r{sup 2}=0.904), carbohydrate, ADF, lignin/ADF, nitrogen and ash (r{sup 2}=0.90) and carbohydrate/ADF, lignin/ADF, lignin and ash (r{sup 2}=0.901) were used. All the models have

  10. Estimation of generation and gravimetric composition of solid wastes at Federal University of Campina Grande, Pombal, Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    Elisângela Maria da Silva

    2018-01-01

    Full Text Available The objective was to present the estimation of the per capita generation and gravimetric composition of the solid residues of the Center of Sciences and Agri-food technology of the Federal University of Campina Grande. These two characteristics are of fundamental importance in the solid waste management process. The methodological procedure was carried out by field survey to identify the number of sectors in the University Campus, as well as the quantification of the daily population that attends the institution. As a result, the daily per capita generation of the Science Center and Environmental Technology was 49.28 g. In relation to the gravimetric composition, it was verified that the organic matter had the highest percentage, representing a total of 66%, followed by 13% of plastics, 9% of paper / cardboard and 8% of composites. It is concluded that the largest part of the total solid waste generated is putrescible organic matter, which was already expected, since solid waste generated in the university campus presents characteristics of household waste.

  11. In-situ Plasticized Cross-linked Polymer Composite Electrolyte Enhanced with Lithium-ion Conducting Nanofibers for Ambient All-Solid-State Lithium-ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Chaoyi; Zhu, Pei; Jia, Hao; Zhu, Jiadeng; Selvan, R. Kalai; Li, Ya; Dong, Xia; Du, Zhuang; Angunawela, Indunil; Wu, Nianqiang; Dirican, Mahmut

    2018-04-29

    Solid electrolytes have been gaining attention recently for the development of next-generation Li-ion batteries due to the substantial improvements in stability and safety. Among various types of solid electrolytes, composite solid electrolytes (CSEs) exhibit both high ionic conductivity and excellent interfacial contact with the electrodes. Incorporating active nanofibers into the polymer matrix demonstrates an effective method to fabricate CSEs. However, current CSEs based on traditional poly(ethylene oxide) (PEO) polymer suffer from the poor ionic conductivity of PEO and agglomeration effect of inorganic fillers at high concentrations, which limit further improvements in Li+ conductivity and electrochemical stability. Herein, we synthesize a novel PEO based cross-linked polymer (CLP) as the polymer matrix with naturally amorphous structure and high room-temperature ionic conductivity of 2.40 × 10-4 S cm-1. Li0.3La0.557TiO3 (LLTO) nanofibers incorporated composite solid electrolytes (L-CLPCSE) exhibit enhanced ionic conductivity without showing filler agglomeration. The high content of Li-conductive nanofibers improves the mechanical strength, ensures the conductive networks, and increases the total Li+ conductivity to 3.31 × 10-4 S cm-1. The all-solid-state Li|LiFePO4 batteries with L-CLPCSE are able to deliver attractive specific capacity of 147 mAh g-1 at room temperature, and no evident dendrite is found at the anode/electrolyte interface after 100 cycles.

  12. Influence of composition of the raw materials on phase formation in solid compounds based on slag and clay minerals

    International Nuclear Information System (INIS)

    Galkin, A.V.; Tolebaev, T.; Omarova, V.I.; Burkitbaev, M.; Blynskiy, A.P.; Bachilova, N.V.; Matsynina, V.I.

    2003-01-01

    Full text: Activation of solidification processes in a compound formed on the basis of slag and clay minerals using sodium hydroxide - the output product from processing the BN-350 sodium coolant it is expedient to form the final product with a phase composition representing (in terms of long term storage) hydro-alumino-silicates incorporating Na-22 and Cs-137 radionuclides, which isomorphly replace other atoms in the crystal lattice sites. Combination of mineral phases, such as alkaline and alkaline-earth hydro-alumino-silicates with zeolite-like structure, providing sorptive properties, and the tobermorite like low-base hydro silicates of calcium defining the physico-mechanical properties of compound is the necessary condition for the compound stability. Investigations of phase formation in the mixtures of Kazakhstan clay, slag materials and alkali have been conducted targeted to control the physico-chemical properties of solid compound. The mixtures of alkali, thermal power plant ashes and clays of various mineralogical genesis (kaolinite, bentonite, Ca-Na-smectite montmorillonite) have been studied. The ashes and phosphorous slag while interacting with alkali are determined to form the non-alkaline hydro-silicates of stavrolite and indianite (anortite) type with free alkali being found in an unbound state. Both alkaline and alkaline-alkaline-earth hydro-silicates of Na 2 Ca 2 Si 2 O 7 H 2 O type are only formed in a compounds containing metallurgical slag. Formation of alkaline hydro-alumino-silicates of NaAlSiO 4 H 2 0 type as well as tomsonite (Na 4 Ca 8 [Al 20S i 20 O 80 ] 24H 2 O) - the zeolite like mineral have been detected in a two-component alkali-clay mixtures. Besides the quantity of tomsonite was determined to be not only dependent on Al 2 O 3 content in clay component but is also defined by stoichiometric composition of the mixture, because zeolite synthesis takes place under conditions of gels co-deposition and high pH value. Maximum quantity of

  13. Aluminum powder size and microstructure effects on properties of boron nitride reinforced aluminum matrix composites fabricated by semi-solid powder metallurgy

    International Nuclear Information System (INIS)

    Chen, Cunguang; Guo, Leichen; Luo, Ji; Hao, Junjie; Guo, Zhimeng; Volinsky, Alex A.

    2015-01-01

    Al matrix composite reinforced by hexagonal boron nitride (h-BN) with nearly full densification was successfully fabricated by the semi-solid powder metallurgy technique. The h-BN/Al composites were synthesized with elemental pure Al powder size of d_5_0=35, 12 and 2 μm. The powder morphology and the structural characteristics of the composites were analyzed using X-ray diffraction, scanning and transmission electron microscopy. The density, Brinell hardness and compressive behavior of the samples were characterized. Density measurement of the Al composites revealed that the composite densification can be effectively promoted by plenty of embedded liquid phase under pressure. Composites prepared using Al powder with varying granularity showed different grain characteristics, and in situ recrystallization occurred inside the original grains with 35 μm Al powder. A sharp interface consisting of Al/Al_2O_3/h-BN was present in the composites. Both the compressive strength and the fracture strain of the investigated composites increased with the decrease of the Al powder size, along with the Brinell hardness. The composite with 2 μm Al powder exhibited the highest relative density (99.3%), Brinell harness (HB 128), compressive strength (763 MPa) and fracture strain (0.299).

  14. X-ray tomography studies on porosity and particle size distribution in cast in-situ Al-Cu-TiB{sub 2} semi-solid forged composites

    Energy Technology Data Exchange (ETDEWEB)

    Mathew, James; Mandal, Animesh [School of Minerals, Metallurgical and Materials Engineering, Indian Institute of Technology, Bhubaneswar (India); Warnett, Jason; Williams, Mark A. [WMG, University of Warwick, Coventry CV4 7AL (United Kingdom); Chakraborty, Madhusudan [Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Kharagpur (India); Srirangam, Prakash, E-mail: p.srirangam@warwick.ac.uk [WMG, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2016-08-15

    X-ray computed tomography (XCT) was used to characterise the internal microstructure and clustering behaviour of TiB{sub 2} particles in in-situ processed Al-Cu metal matrix composites prepared by casting method. Forging was used in semi-solid state to reduce the porosity and to uniformly disperse TiB{sub 2} particles in the composite. Quantification of porosity and clustering of TiB{sub 2} particles was evaluated for different forging reductions (30% and 50% reductions) and compared with an as-cast sample using XCT. Results show that the porosity content was decreased by about 40% due to semi-solid forging as compared to the as-cast condition. Further, XCT results show that the 30% forging reduction resulted in greater uniformity in distribution of TiB{sub 2} particles within the composite compared to as-cast and the 50% forge reduction in semi-solid state. These results show that the application of forging in semi-solid state enhances particle distribution and reduces porosity formation in cast in-situ Al-Cu-TiB{sub 2} metal matrix composites. - Highlights: •XCT was used to visualise 3D internal structure of Al-Cu-TiB{sub 2} MMCs. •Al-Cu-TiB{sub 2} MMC was prepared by casting using flux assisted synthesis method. •TiB{sub 2} particles and porosity size distribution were evaluated. •Results show that forging in semi-solid condition decreases the porosity content and improve the particle dispersion in MMCs.

  15. Launch Vehicle Performance for Bipropellant Propulsion Using Atomic Propellants With Oxygen

    Science.gov (United States)

    Palaszewski, Bryan

    2000-01-01

    Atomic propellants for bipropellant launch vehicles using atomic boron, carbon, and hydrogen were analyzed. The gross liftoff weights (GLOW) and dry masses of the vehicles were estimated, and the 'best' design points for atomic propellants were identified. Engine performance was estimated for a wide range of oxidizer to fuel (O/F) ratios, atom loadings in the solid hydrogen particles, and amounts of helium carrier fluid. Rocket vehicle GLOW was minimized by operating at an O/F ratio of 1.0 to 3.0 for the atomic boron and carbon cases. For the atomic hydrogen cases, a minimum GLOW occurred when using the fuel as a monopropellant (O/F = 0.0). The atomic vehicle dry masses are also presented, and these data exhibit minimum values at the same or similar O/F ratios as those for the vehicle GLOW. A technology assessment of atomic propellants has shown that atomic boron and carbon rocket analyses are considered to be much more near term options than the atomic hydrogen rockets. The technology for storing atomic boron and carbon has shown significant progress, while atomic hydrogen is not able to be stored at the high densities needed for effective propulsion. The GLOW and dry mass data can be used to estimate the cost of future vehicles and their atomic propellant production facilities. The lower the propellant's mass, the lower the overall investment for the specially manufactured atomic propellants.

  16. On the combustion mechanisms of ZrH2 in double-base propellant.

    Science.gov (United States)

    Yang, Yanjing; Zhao, Fengqi; Yuan, Zhifeng; Wang, Ying; An, Ting; Chen, Xueli; Xuan, Chunlei; Zhang, Jiankan

    2017-12-13

    Metal hydrides are regarded as a series of promising hydrogen-supplying fuel for solid rocket propellants. Their effects on the energetic and combustion performances of propellants are closely related to their reaction mechanisms. Here we report a first attempt to determine the reaction mechanism of ZrH 2 , a high-density metal hydride, in the combustion of a double-base propellant to evaluate its potential as a fuel. ZrH 2 is determined to possess good resistance to oxidation by nitrocellulose and nitroglycerine. Thus its combustion starts with dehydrogenation to generate H 2 and metallic Zr. Subsequently, the newly formed Zr and H 2 participate in the combustion and, especially, Zr melts and then combusts on the burning surface which favors the heat feedback to the propellant. This phenomenon is completely different from the combustion behavior of the traditional fuel Al, where the Al particles are ejected off the burning surface of the propellant to get into the luminous flame zone to burn. The findings in this work validate the potential of ZrH 2 as a hydrogen-supplying fuel for double-base propellants.

  17. Theoretical prediction of morphotropic compositions in Na1/2Bi1/2TiO3-based solid solutions from transition pressures

    Science.gov (United States)

    Gröting, Melanie; Albe, Karsten

    2014-02-01

    In this article we present a method based on ab initio calculations to predict compositions at morphotropic phase boundaries in lead-free perovskite solid solutions. This method utilizes the concept of flat free energy surfaces and involves the monitoring of pressure-induced phase transitions as a function of composition. As model systems, solid solutions of Na1/2Bi1/2TiO3 with the alkali substituted Li1/2Bi1/2TiO3 and K1/2Bi1/2TiO3 and the alkaline earth substituted CaTiO3 and BaTiO3 are chosen. The morphotropic compositions are identified by determining the composition at which the phase transition pressure equals zero. In addition, we discuss the different effects of hydrostatic pressure (compression and tension) and chemical substitution on the antiphase tilts about the [111] axis (a-a-a-) present in pure Na1/2Bi1/2TiO3 and how they develop in the two solid solutions Na1/2Bi1/2TiO3-CaTiO3 and Na1/2Bi1/2TiO3-BaTiO3. Finally, we discuss the advantages and shortcomings of this simple computational approach.

  18. 78 FR 4038 - Critical Parts for Airplane Propellers

    Science.gov (United States)

    2013-01-18

    ... manufacturers are not required to provide information concerning propeller critical part design, manufacture, or... engineering, manufacturing, and service management processes should provide clear information for propeller... manufacture critical parts for airplane propellers update their manuals to record engineering, manufacture...

  19. KAPPEL Propeller. Development of a Marine Propeller with Non-planar Lifting Surfaces

    DEFF Research Database (Denmark)

    Kappel, J.; Andersen, Poul

    2002-01-01

    The principle of non-planar lifting surfaces is applied to the design of modern aircraft wings to obtain better lift to drag ratios. Whereas a pronounced fin or "winglet" at the wingtip has been developed for aircraft, the application of the non-planar principle to marine propellers, dealt...... with in this paper, has led to the KAPPEL propeller with blades curved towards the suction side integrating the fin or winglet into the propeller blade. The combined theoretical, experimental and practical approach to develop and design marine propellers with non-planar lifting surfaces has resulted in propellers...

  20. Computational Fluid Dynamics Simulation of Combustion Instability in Solid Rocket Motor : Implementation of Pressure Coupled Response Function

    OpenAIRE

    S. Saha; D. Chakraborty

    2016-01-01

    Combustion instability in solid propellant rocket motor is numerically simulated by implementing propellant response function with quasi steady homogeneous one dimensional formulation. The convolution integral of propellant response with pressure history is implemented through a user defined function in commercial computational fluid dynamics software. The methodology is validated against literature reported motor test and other simulation results. Computed amplitude of pressure fluctuations ...

  1. Green plasticizers for multibase gun propellants (Lecture)

    NARCIS (Netherlands)

    Schoolderman, C.; Driel, C.A. van; Zebregs, M.

    2007-01-01

    TNO Defence, Security and Safety has a long history of research on gun propellants. Areas investigated are formulating (new ingredients, optimization), manufacturing, charge design and lifetime assessment [1,2,3,4,5]. In conventional propellants inert plasticizers are used to alter performance,

  2. A novel poly(deep eutectic solvent)-based magnetic silica composite for solid-phase extraction of trypsin

    International Nuclear Information System (INIS)

    Xu, Kaijia; Wang, Yuzhi; Li, Yixue; Lin, Yunxuan; Zhang, Haibao; Zhou, Yigang

    2016-01-01

    Novel poly(deep eutectic solvent) grafted silica-coated magnetic microspheres (Fe 3 O 4 @SiO 2 -MPS@PDES) were prepared by polymerization of choline chloride-itaconic acid (ChCl-IA) and γ-MPS-modified magnetic silica composites, and were characterized by vibrating sample magnetometer (VSM), Fourier transform infrared spectrometry (FT-IR), X-ray photoelectron spectra (XPS), thermal gravimetric analysis (TGA) and transmission electron microscope (TEM). Then the synthetic Fe 3 O 4 @SiO 2 -MPS@PDES microspheres were applied for the magnetic solid-phase extraction (MSPE) of trypsin for the first time. After extraction, the concentration of trypsin in the supernatant was determined by a UV–vis spectrophotometer. Single factor experiments were carried out to investigate the effects of the extraction process, including the concentration of trypsin, the ionic strength, the pH value, the extraction time and the temperature. Experimental results showed the extraction capacity could reach up to 287.5 mg/g under optimized conditions. In comparison with Fe 3 O 4 @SiO 2 -MPS, Fe 3 O 4 @SiO 2 -MPS@PDES displayed higher extraction capacity and selectivity for trypsin. According to the regeneration studies, Fe 3 O 4 @SiO 2 -MPS@PDES microspheres can be recycled six times without significant loss of its extraction capacity, and retained a high extraction capacity of 233 mg/g after eight cycles. Besides, the activity studies also demonstrated that the activity of the extracted trypsin was well retained. Furthermore, the analysis of real sample revealed that the prepared magnetic microspheres can be used to purify trypsin in crude bovine pancreas extract. These results highlight the potential of the proposed Fe 3 O 4 @SiO 2 -MPS@PDES-MSPE method in separation of biomolecules. - Highlights: • A strategy for solid-phase extraction of trypsin based on poly(deep eutectic solvent) modified magnetic silica microspheres. • Fe 3 O 4 @SiO 2 -MPS@PDES showed higher extraction capacity

  3. A novel poly(deep eutectic solvent)-based magnetic silica composite for solid-phase extraction of trypsin

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Kaijia [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082 (China); Wang, Yuzhi, E-mail: wyzss@hnu.edu.cn [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082 (China); Li, Yixue; Lin, Yunxuan; Zhang, Haibao [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082 (China); Zhou, Yigang [Department of Microbiology, College of Basic Medicine, Central South University, Changsha, 410083 (China)

    2016-11-23

    Novel poly(deep eutectic solvent) grafted silica-coated magnetic microspheres (Fe{sub 3}O{sub 4}@SiO{sub 2}-MPS@PDES) were prepared by polymerization of choline chloride-itaconic acid (ChCl-IA) and γ-MPS-modified magnetic silica composites, and were characterized by vibrating sample magnetometer (VSM), Fourier transform infrared spectrometry (FT-IR), X-ray photoelectron spectra (XPS), thermal gravimetric analysis (TGA) and transmission electron microscope (TEM). Then the synthetic Fe{sub 3}O{sub 4}@SiO{sub 2}-MPS@PDES microspheres were applied for the magnetic solid-phase extraction (MSPE) of trypsin for the first time. After extraction, the concentration of trypsin in the supernatant was determined by a UV–vis spectrophotometer. Single factor experiments were carried out to investigate the effects of the extraction process, including the concentration of trypsin, the ionic strength, the pH value, the extraction time and the temperature. Experimental results showed the extraction capacity could reach up to 287.5 mg/g under optimized conditions. In comparison with Fe{sub 3}O{sub 4}@SiO{sub 2}-MPS, Fe{sub 3}O{sub 4}@SiO{sub 2}-MPS@PDES displayed higher extraction capacity and selectivity for trypsin. According to the regeneration studies, Fe{sub 3}O{sub 4}@SiO{sub 2}-MPS@PDES microspheres can be recycled six times without significant loss of its extraction capacity, and retained a high extraction capacity of 233 mg/g after eight cycles. Besides, the activity studies also demonstrated that the activity of the extracted trypsin was well retained. Furthermore, the analysis of real sample revealed that the prepared magnetic microspheres can be used to purify trypsin in crude bovine pancreas extract. These results highlight the potential of the proposed Fe{sub 3}O{sub 4}@SiO{sub 2}-MPS@PDES-MSPE method in separation of biomolecules. - Highlights: • A strategy for solid-phase extraction of trypsin based on poly(deep eutectic solvent) modified magnetic silica

  4. Oral processing characteristics of solid savoury meal components, and relationship with food composition, sensory attributes and expected satiation.

    Science.gov (United States)

    Forde, C G; van Kuijk, N; Thaler, T; de Graaf, C; Martin, N

    2013-01-01

    The modern food supply is often dominated by a large variety of energy dense, softly textured foods that can be eaten quickly. Previous studies suggest that particular oral processing characteristics such as large bite size and lack of chewing activity contribute to the low satiating efficiency of these foods. To better design meals that promote greater feelings of satiation, we need an accurate picture of the oral processing characteristics of a range of solid food items that could be used to replace softer textures during a normal hot meal. The primary aim of this study was to establish an accurate picture of the oral processing characteristics of a set of solid savoury meal components. The secondary aim was to determine the associations between oral processing characteristics, food composition, sensory properties, and expected satiation. In a within subjects design, 15 subjects consumed 50 g of 35 different savoury food items over 5 sessions. The 35 foods represented various staples, vegetables and protein rich foods such a meat and fish. Subjects were video-recorded during consumption and measures included observed number of bites, number of chews, number of swallows and derived measures such as chewing rate, eating rate, bite size, and oral exposure time. Subjects rated expected satiation for a standard 200 g portion of each food using a 100mm and the sensory differences between foods were quantified using descriptive analysis with a trained sensory panel. Statistical analysis focussed on the oral processing characteristics and associations between nutritional, sensory and expected satiation parameters of each food. Average number of chews for 50 g of food varied from 27 for mashed potatoes to 488 for tortilla chips. Oral exposure time was highly correlated with the total number of chews, and varied from 27 s for canned tomatoes to 350 s for tortilla chips. Chewing rate was relatively constant with an overall average chewing rate of approximately 1 chew

  5. Composites

    International Nuclear Information System (INIS)

    Kasen, M.B.

    1983-01-01

    This chapter discusses the roles of composite laminates and aggregates in cryogenic technology. Filamentary-reinforced composites are emphasized because they are the most widely used composite materials. Topics considered include composite systems and terminology, design and fabrication, composite failure, high-pressure reinforced plastic laminates, low-pressure reinforced plastics, reinforced metals, selectively reinforced structures, the effect of cryogenic temperatures, woven-fabric and random-mat composites, uniaxial fiber-reinforced composites, composite joints in cryogenic structures, joining techniques at room temperature, radiation effects, testing laminates at cryogenic temperatures, static and cyclic tensile testing, static and cyclic compression testing, interlaminar shear testing, secondary property tests, and concrete aggregates. It is suggested that cryogenic composite technology would benefit from the development of a fracture mechanics model for predicting the fitness-for-purpose of polymer-matrix composite structures

  6. Ignition and combustion characteristics of metallized propellants

    Science.gov (United States)

    Turns, Stephen R.; Mueller, D. C.

    1993-01-01

    Experimental and analytical investigations focusing on secondary atomization and ignition characteristics of aluminum/liquid hydrocarbon slurry propellants were conducted. Experimental efforts included the application of a laser-based, two-color, forward-scatter technique to simultaneously measure free-flying slurry droplet diameters and velocities for droplet diameters in the range of 10-200 microns. A multi-diffusion flame burner was used to create a high-temperature environment into which a dilute stream of slurry droplets could be introduced. Narrowband measurements of radiant emission were used to determine if ignition of the aluminum in the slurry droplet had occurred. Models of slurry droplet shell formation were applied to aluminum/liquid hydrocarbon propellants and used to ascertain the effects of solids loading and ultimate particle size on the minimum droplet diameter that will permit secondary atomization. For a 60 weight-percent Al slurry, the limiting critical diameter was predicted to be 34.7 microns which is somewhat greater than the 20-25 micron limiting diameters determined in the experiments. A previously developed model of aluminum ignition in a slurry droplet was applied to the present experiments and found to predict ignition times in reasonable agreement with experimental measurements. A model was also developed that predicts the mechanical stress in the droplet shell and a parametric study was conducted. A one-dimensional model of a slurry-fueled rocket combustion chamber was developed. This model includes the processes of liquid hydrocarbon burnout, secondary atomization, aluminum ignition, and aluminum combustion. Also included is a model for radiant heat transfer from the hot aluminum oxide particles to the chamber walls. Exercising this model shows that only a modest amount of secondary atomization is required to reduce residence times for aluminum burnout, and thereby maintain relatively short chamber lengths. The model also predicts

  7. Microstructure, mechanical response and fractography of AZ91E/Al2O3 (p nano composite fabricated by semi solid stir casting method

    Directory of Open Access Journals (Sweden)

    Sameer Kumar D.

    2017-03-01

    Full Text Available The present study confers to the fabrication and its characterization of magnesium alloy (AZ91E based nano composites with nano Al2O3 particulate reinforcements. A novel Semi Solid stir casting technique was adopted for the fabrication of the composite. An average particle size of 50 nm was used as reinforcement to disperse in matrix. The effects of change in weight fraction of reinforcements on the distribution of particles, particle–matrix interfacial reactions, physical as well as mechanical properties were reported. The SEM and EDS analysis has shown the uniform distribution of particles in the composite along with the presence of elements. The mechanical properties of reinforced and unreinforced composite were evaluated and presented. Fractography of tensile specimens was also discussed.

  8. Test Report for Cesium and Solids Removal from an 11.5L Composite of Archived Hanford Double Shell Tank Supernate for Off-Site Disposal.

    Energy Technology Data Exchange (ETDEWEB)

    Doll, S. R.; Cooke, G. A.

    2017-08-31

    The 222-S Laboratory blended supernate waste from Hanford Tanks 241-AN-101, 241-AN- 106, 241-AP-105, 241-AP-106, 241-AP-107, and 241-AY-101 from the hot cell archive to create a bulk composite. The composite was blended with 600 mL 19.4 M NaOH, which brought the total volume to approximately 11.5 L (3 gal). The composite was filtered to remove solids and passed through spherical resorcinol-formaldehyde ion-exchange resin columns to remove cesium. The composite masses were tracked as a treatability study. Samples collected before, during, and after the ion exchange process were characterized for a full suite of analytes (inorganic, organic, and radionuclides) to aid in the classification of the waste for shipping, receiving, treatment, and disposal determinations.

  9. Test Report for Cesium and Solids Removal from an 11.5L Composite of Archived Hanford Double Shell Tank Supernate for Off-Site Disposal

    Energy Technology Data Exchange (ETDEWEB)

    Doll, Stephanie R. [Hanford Site (HNF), Richland, WA (United States); Cooke, Gary A. [Hanford Site (HNF), Richland, WA (United States)

    2017-08-31

    The 222-S Laboratory blended supernate waste from Hanford Tanks 241-AN-101, 241-AN- 106, 241-AP-105, 241-AP-106, 241-AP-107, and 241-AY-101 from the hot cell archive to create a bulk composite. The composite was blended with 600 mL 19.4 M NaOH, which brought the total volume to approximately 11.5 L (3 gal). The composite was filtered to remove solids and passed through spherical resorcinol-formaldehyde ion-exchange resin columns to remove cesium. The composite masses were tracked as a treatability study. Samples collected before, during, and after the ion-exchange process were characterized for a full suite of analytes (inorganic, organic, and radionuclides) to aid in the classification of the waste for shipping, receiving, treatment, and disposal determinations.

  10. Tests on thirteen navy type model propellers

    Science.gov (United States)

    Durand, W F

    1927-01-01

    The tests on these model propellers were undertaken for the purpose of determining the performance coefficients and characteristics for certain selected series of propellers of form and type as commonly used in recent navy designs. The first series includes seven propellers of pitch ratio varying by 0.10 to 1.10, the area, form of blade, thickness, etc., representing an arbitrary standard propeller which had shown good results. The second series covers changes in thickness of blade section, other things equal, and the third series, changes in blade area, other things equal. These models are all of 36-inch diameter. Propellers A to G form the series on pitch ratio, C, N. I. J the series on thickness of section, and K, M, C, L the series on area. (author)

  11. Small-Scale Shock Testing of Propellants and Ingredients

    National Research Council Canada - National Science Library

    Dawley, S

    2004-01-01

    .... The use of small-scale gap testing to evaluate the shock sensitivity of individual propellant ingredients and propellant formulations is a valuable method for experimentally establishing shock...

  12. Deflagration of thermite - ammonium nitrate based propellant mixture

    Science.gov (United States)

    Duraes, Luisa; Morgado, Joel; Portugal, Antonio; Campos, Jose

    2001-06-01

    Reaction between iron oxide (Fe2O3) and aluminum (Al) is the reference of the classic thermite compositions. The efficency of the reaction, for a given initial composition of Fe2O3 and Al, is evaluated by the final temperature and by the mass ratio of Al2O3 /AlO in products of combustion (in condensed phase). In order to increase pressure in products of thermite reaction, the original composition is mixed, with an original twin screw extruder, with a propellant binder composed of ammonium and sodium nitrates, initialy solved in formamide (CH3NO) and mixed with a polyurethane solution. The products of combustion and pyrolysis of this binder, reacting with thermite products, generates high pressure and high temperature conditions. These experimental conditions are also predicted using THOR code. The study presents DSC and TGA results of components and mixtures, and correlates them to the ignition phenomena and reaction properties. The regression rate of combustion and final attained temperature and pressure, in a closed confinement, as a function of composition of thermite components/propellant binder, are presented and discussed. They show the influence of gaseous combustion and pyrolysis products of binder in final reaction.

  13. Major- and minor-metal composition of three distinct solid material fractions associated with Juan de Fuca hydrothermal fluids (northeast Pacific), and calculation of dilution fluid samples

    Science.gov (United States)

    Hinkley, T.K.; Seeley, J.L.; Tatsumoto, M.

    1988-01-01

    Three distinct types of solid material are associated with each sample of the hydrothermal fluid that was collected from the vents of the Southern Juan de Fuca Ridge. The solid materials appear to be representative of deposits on ocean floors near mid-ocean ridges, and interpretation of the chemistry of the hydrothermal solutions requires understanding of them. Sr isotopic evidence indicates that at least two and probably all three of these solid materials were removed from the solution with which they are associated, by precipitation or adsorption. This occurred after the "pure" hydrothermal fluid was diluted and thoroughly mixed with ambient seawater. The three types of solid materials, are, respectively, a coarse Zn- and Fe-rich material with small amounts of Na and Ca; a finer material also rich in Zn and Fe, but with alkali and alkaline-earth metals; and a scum composed of Ba or Zn, with either considerable Fe or Si, and Sr. Mineral identification is uncertain because of uncertain anion composition. Only in the cases of Ba and Zn were metal masses greater in solid materials than in the associated fluids. For all other metals measured, masses in fluids dwarf those in solids. The fluids themselves contain greater concentrations of all metals measured, except Mg, than seawater. We discuss in detail the relative merits of two methods of determining the mixing proportions of "pure" hydrothermal solution and seawater in the fluids, one based on Sr isotopes, and another previously used method based on Mg concentrations. Comparison of solute concentrations in the several samples shows that degree of dilution of "pure" hydrothermal solutions by seawater, and amounts of original solutes that were removed from it as solid materials, are not related. There is no clear evidence that appreciable amounts of solid materials were not conserved (lost) either during or prior to sample collection. ?? 1988.

  14. Reduced graphene oxide-wrapped MoO3 composites prepared by using metal-organic frameworks as precursor for all-solid-state flexible supercapacitors.

    Science.gov (United States)

    Cao, Xiehong; Zheng, Bing; Shi, Wenhui; Yang, Jian; Fan, Zhanxi; Luo, Zhimin; Rui, Xianhong; Chen, Bo; Yan, Qingyu; Zhang, Hua

    2015-08-26

    Reduced graphene oxide-wrapped MoO3M (rGO/MoO3 ) is prepared by a novel and simple method that is developed by using a metal-organic framework as the precursor. After a two-step annealing process, the obtained rGO/MoO3 composite is used for a high-performance supercapacitor electrode. Moreover, an all-solid-state flexible supercapacitor is fabricated based on the rGO/MoO3 composite, which shows stable performance under different bending states. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Development of a portable mass spectrometric system for determination of isotopic composition of solid uranium samples using fluorine volatilization. Final report

    International Nuclear Information System (INIS)

    Loge, G.

    1994-01-01

    Using hardware and materials supplied by LANL, a prototype quadrupole mass spectrometer system designed for portable field analysis of isotopic composition of solid uranium samples was assembled and tested. The system contained the capability for fluorine volatilization of solid uranium samples with gas introduction, which was successfully tested and demonstrated using 100 mg samples of U 3 O 8 . Determination of precision and accuracy for measuring isotopic composition was performed using isotopic standards. Use with soil samples containing uranium were also attempted. Silicates in the soil forming SiF 4 were found to be a kinetic bottleneck to the formation of UF 6 . This could be avoided by performing some sort of chemical separation as a pre-treatment step, which was demonstrated using nitric acid

  16. A novel poly(deep eutectic solvent)-based magnetic silica composite for solid-phase extraction of trypsin.

    Science.gov (United States)

    Xu, Kaijia; Wang, Yuzhi; Li, Yixue; Lin, Yunxuan; Zhang, Haibao; Zhou, Yigang

    2016-11-23

    Novel poly(deep eutectic solvent) grafted silica-coated magnetic microspheres (Fe 3 O 4 @SiO 2 -MPS@PDES) were prepared by polymerization of choline chloride-itaconic acid (ChCl-IA) and γ-MPS-modified magnetic silica composites, and were characterized by vibrating sample magnetometer (VSM), Fourier transform infrared spectrometry (FT-IR), X-ray photoelectron spectra (XPS), thermal gravimetric analysis (TGA) and transmission electron microscope (TEM). Then the synthetic Fe 3 O 4 @SiO 2 -MPS@PDES microspheres were applied for the magnetic solid-phase extraction (MSPE) of trypsin for the first time. After extraction, the concentration of trypsin in the supernatant was determined by a UV-vis spectrophotometer. Single factor experiments were carried out to investigate the effects of the extraction process, including the concentration of trypsin, the ionic strength, the pH value, the extraction time and the temperature. Experimental results showed the extraction capacity could reach up to 287.5 mg/g under optimized conditions. In comparison with Fe 3 O 4 @SiO 2 -MPS, Fe 3 O 4 @SiO 2 -MPS@PDES displayed higher extraction capacity and selectivity for trypsin. According to the regeneration studies, Fe 3 O 4 @SiO 2 -MPS@PDES microspheres can be recycled six times without significant loss of its extraction capacity, and retained a high extraction capacity of 233 mg/g after eight cycles. Besides, the activity studies also demonstrated that the activity of the extracted trypsin was well retained. Furthermore, the analysis of real sample revealed that the prepared magnetic microspheres can be used to purify trypsin in crude bovine pancreas extract. These results highlight the potential of the proposed Fe 3 O 4 @SiO 2 -MPS@PDES-MSPE method in separation of biomolecules. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Nanocrystalline solids

    International Nuclear Information System (INIS)

    Gleiter, H.

    1991-01-01

    Nanocrystalline solids are polycrystals, the crystal size of which is a few (typically 1 to 10) nanometres so that 50% or more of the solid consists of incoherent interfaces between crystals of different orientations. Solids consisting primarily of internal interfaces represent a separate class of atomic structures because the atomic arrangement formed in the core of an interface is known to be an arrangement of minimum energy in the potential field of the two adjacent crystal lattices with different crystallographic orientations on either side of the boundary core. These boundary conditions result in atomic structures in the interfacial cores which cannot be formed elsewhere (e.g. in glasses or perfect crystals). Nanocrystalline solids are of interest for the following four reasons: (1) Nanocrystalline solids exhibit an atomic structure which differs from that of the two known solid states: the crystalline (with long-range order) and the glassy (with short-range order). (2) The properties of nanocrystalline solids differ (in some cases by several orders of magnitude) from those of glasses and/or crystals with the same chemical composition, which suggests that they may be utilized technologically in the future. (3) Nanocrystalline solids seem to permit the alloying of conventionally immiscible components. (4) If small (1 to 10 nm diameter) solid droplets with a glassy structure are consolidated (instead of small crystals), a new type of glass, called nanoglass, is obtained. Such glasses seem to differ structurally from conventional glasses. (orig.)

  18. CW-Laser-Induced Solid-State Reactions in Mixed Micron-Sized Particles of Silicon Monoxide and Titanium Monoxide: Nano-Structured Composite with Visible Light Absorption

    Czech Academy of Sciences Publication Activity Database

    Křenek, T.; Tesař, J.; Kupčík, Jaroslav; Netrvalová, M.; Pola, M.; Jandová, Věra; Pokorná, Dana; Cuřínová, Petra; Bezdička, Petr; Pola, Josef

    2017-01-01

    Roč. 27, č. 6 (2017), s. 1640-1648 ISSN 1574-1443 Institutional support: RVO:61388980 ; RVO:67985858 Keywords : Cw CO2 laser heating * IR laser imaging * Silicon monoxide * Solid state redox reactions * Ti/Si/O composite * Titanium monoxide Subject RIV: CA - Inorganic Chemistry; CI - Industrial Chemistry, Chemical Engineering (UCHP-M) OBOR OECD: Inorganic and nuclear chemistry; Chemical process engineering (UCHP-M) Impact factor: 1.577, year: 2016

  19. Composition control of low-volatile solids through chemical vapor transport reactions. III. The example of gallium monoselenide: Control of the polytypic structure, non-stoichiometry and properties

    International Nuclear Information System (INIS)

    Zavrazhnov, A.; Naumov, A.; Sidey, V.; Pervov, V.

    2012-01-01

    Highlights: ► This work is devoted to the composition control of solids with selective CVT method. ► Phase identity and non-stoichiometry of solids (GaSe, etc.) depend on CVT-temperatures. ► The interrelation between the properties of GaSe and CVT conditions is also found. ► For iodide transporting system the diagram of phase stability of solids is adjusted. ► High temperatures and Se-rich non-stoichiometry are necessary for γ-GaSe stability. - Abstract: By means of particular examples, the present work demonstrates the possibility of directed delicate non-destructive control of structure, composition and properties of inorganic solids using the method of selective chemical vapor transport (SCVT). Gallium monoselenide GaSe is the main model object. Additional, though less detailed, explanation is given by the example of gallium monosulfide GaS. Experimental evidences on the possibility of the control of polytypic structure, non-stoichiometry and properties of gallium monoselenide were obtained in non-isothermal variant of selective chemical vapor transport which has non-destructive character. Diagnostics of the phase (polytypic) composition and non-stoichiometry of GaSe was performed with the use of X-ray diffractometry as well as with the use of cathode luminescence spectra. It was experimentally found that there exists a connection of non-stoichiometry and the properties of gallium selenides with the determining conditions of selective chemical vapor transport: temperature of controlled sample (T 2 ) and the difference of temperatures between the hot and cold zones (ΔT). It is shown that the phase diagram of Ga–Se system needs to be partially revised near the composition of Ga 1 Se 1 . The reason for such revision is the fact that two polytypes (ε-GaSe and γ-GaSe) exist on this phase diagram as independent phases.

  20. Surface composition variation and high-vacuum performance of DLC/ILs solid-liquid lubricating coatings: Influence of space irradiation

    International Nuclear Information System (INIS)

    Liu Xiufang; Wang Liping; Pu Jibin; Xue Qunji

    2012-01-01

    In this paper, we fabricated a DLC/ionic liquid (DLC/ILs) solid-liquid lubricating coating and investigated the effect of atomic oxygen (AO), ultraviolet (UV), proton and electron irradiations on composition, structure, morphology and tribological properties of the DLC/ILs solid-liquid lubricating coatings. A ground-based simulation facility was employed to carry out the irradiation experiments. X-ray photoelectron spectroscope (XPS), Raman spectra, and Fourier Transform Infrared Spectroscopy (FTIR) were used to analyzed the structure and composition changes of DLC film and IL lubricant before and after irradiations. The tribological behavior of the DLC/ILs solid-liquid lubricating coating before and after irradiations was investigated by a vacuum tribometer with the pressure of 10 -5 Pa. The experimental results revealed that irradiations induced the structural changes, including oxidation, bond break and crosslinking reactions of DLC film and IL lubricant. The damage of proton and AO irradiations to lubricating materials were the most serious, and UV irradiation was the slightest. After irradiations, the friction coefficient of the solid-liquid lubricating coatings decreased (except for AO irradiation), but the disc wear rate increased compared with non-irradiation coatings.

  1. Spectral Studies of Solid Propellant Combustion. 3. Emission and Absorption Results for HMX2 Propellant

    Science.gov (United States)

    1991-05-01

    funding from the Anry Productivity Capital Investment Program. vii INTENTioNALLY LEFT BL~ANK viH I. INTRODUCTION During the last several years we...G-23 Dahlgren, VA 22448-5000 1 OSD/SDIO/ IST ATTN: L. Caveny 2 Commander Pentagon Naval Surface Warfare Center Washington, DC 20301-7100 ATTN: R

  2. New Delivery Systems and Propellants

    Directory of Open Access Journals (Sweden)

    Myrna Dolovich

    1999-01-01

    Full Text Available The removal of chlorofluorocarbon (CFC propellants from industrial and household products has been agreed to by over 165 countires of which more than 135 are developing countries. The timetable for this process is outlined in the Montreal Protocol on Substances that Deplete the Ozone Layer document and in several subsequent amendments. Pressured metered dose inhalers (pMDIs for medical use have been granted temporary exemptions until replacement formulations, providing the same medication via the same route, and with the same efficacy and safety profiles, are approved for human use. Hydrofluoroalkanes (HFAs are the alternative propellants for CFCs-12 and -114. Their potential for damage to the ozone layer is nonexistent, and while they are greenhouse gases, their global warming potential is a fraction (one-tenth of that of CFCs. Replacement formulations for almost all inhalant respiratory medications have been or are being produced and tested; in Canada, it is anticipated that the transition to these HFA or CFC-free pMDIs will be complete by the year 2005. Initially, an HFA pMDI was to be equivalent to the CFC pMDI being replaced, in terms of aerosol properties and effective clinical dose. However, this will not necessarily be the situation, particularly for some corticosteroid products. Currently, only one CFC-free formulation is available in Canada – Airomir, a HFA salbutamol pMDI. This paper discusses the in vitro aerosol characteristics, in vivo deposition and clinical data for several HFA pMDIs for which there are data available in the literature. Alternative delivery systems to the pMDI, namely, dry powder inhalers and nebulizers, are briefly reviewed.

  3. Design methods in solid rocket motors

    Energy Technology Data Exchange (ETDEWEB)

    1987-03-01

    A compilation of lectures summarizing the current state-of-the-art in designing solid rocket motors and and their components is presented. The experience of several countries in the use of new technologies and methods is represented. Specific sessions address propellant grains, cases, nozzles, internal thermal insulation, and the general optimization of solid rocket motor designs.

  4. Raman scattering quantitative analysis of the anion chemical composition in kesterite Cu2ZnSn(SxSe1−x)4 solid solutions

    International Nuclear Information System (INIS)

    Dimitrievska, Mirjana; Gurieva, Galina; Xie, Haibing; Carrete, Alex; Cabot, Andreu; Saucedo, Edgardo; 2UB, Departament d’Electrònica, Universitat de Barcelona, C. Martí i Franquès 1, 08028 Barcelona (Spain))" data-affiliation=" (Catalonia Institute for Energy Research (IREC), Jardins de les Dones de Negre 1 2pl., 08930 Sant Adrià del Besòs, Barcelona (Spain); IN2UB, Departament d’Electrònica, Universitat de Barcelona, C. Martí i Franquès 1, 08028 Barcelona (Spain))" >Pérez-Rodríguez, Alejandro

    2015-01-01

    Highlights: • An optical method for the quantitative measurement of [S]/([S] + [Se]) in CZTSSe is presented. • It is based on Raman spectroscopy and covers whole S–Se range of compositions. • The proposed method is independent of crystal quality, experimental conditions and type of material. • The validity of the technique is proven by comparison with independent composition measurements (XRD and EQE). • Test of the method on the data published in the literature has given satisfactory results. - Abstract: A simple and non destructive optical methodology for the quantitative measurement of [S]/([S] + [Se]) anion composition in kesterite Cu 2 ZnSn(S x Se 1−x ) 4 (CZTSSe) solid solutions by means of Raman spectroscopy in the whole S–Se range of compositions has been developed. This methodology is based on the dependence of the integral intensity ratio of Raman bands sensitive to anion vibrations with the [S]/([S] + [Se]) composition of the kesterite solid solutions. The calibration of the parameters used in this analysis involved the synthesis of a set of CZTSSe powders by solid state reaction method, spanning the range from pure Cu 2 ZnSnS 4 to pure Cu 2 ZnSnSe 4 . The validity of the methodology has been tested on different sets of independent samples, including also non-stoichiometric device grade CZTSSe layers with different compositions and films that were synthesized by solution based processes with different crystalline quality. In all cases, the comparison of the results obtained from the analysis of the intensity of the Raman bands with independent composition measurements performed by different techniques as X-ray diffraction and external quantum efficiency has confirmed the satisfactory performance of the developed methodology for the quantitative analysis of these compounds, independently on the crystal quality or the method of synthesis. Further strong support on the methodology performance has been obtained from the analysis of a wider

  5. Development of Static Balance Measurement and Correction Compound Platform for Single Blade of Controllable Pitch Propeller

    Science.gov (United States)

    Chao, Zhang; Shijie, Su; Yilin, Yang; Guofu, Wang; Chao, Wang

    2017-11-01

    Aiming at the static balance of the controllable pitch propeller (CPP), a high efficiency static balance method based on the double-layer structure of the measuring table and gantry robot is adopted to realize the integration of torque measurement and corrected polish for controllable pitch propeller blade. The control system was developed by Microsoft Visual Studio 2015, and a composite platform prototype was developed. Through this prototype, conduct an experiment on the complete process of torque measurement and corrected polish based on a 300kg class controllable pitch propeller blade. The results show that the composite platform can correct the static balance of blade with a correct, efficient and labor-saving operation, and can replace the traditional method on static balance of the blade.

  6. Composition

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2011-01-01

    Strategies are open compositions to be realised by improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". Caution: streaming the sound files will in some cases only provide a few minutes' sample. Please DOWNLOAD them to hear them in full...

  7. Composition

    DEFF Research Database (Denmark)

    2014-01-01

    Memory Pieces are open compositions to be realised solo by an improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". Caution: streaming the sound files will in some cases only provide a few minutes' sample. Please DOWNLOAD them to hear them...

  8. Energy coefficients for a propeller series

    DEFF Research Database (Denmark)

    Olsen, Anders Smærup

    2004-01-01

    The efficiency for a propeller is calculated by energy coefficients. These coefficients are related to four types of losses, i.e. the axial, the rotational, the frictional, and the finite blade number loss, and one gain, i.e. the axial gain. The energy coefficients are derived by use...... of the potential theory with the propeller modelled as an actuator disk. The efficiency based on the energy coefficients is calculated for a propeller series. The results show a good agreement between the efficiency based on the energy coefficients and the efficiency obtained by a vortex-lattice method....

  9. Noise from Two-Blade Propellers

    Science.gov (United States)

    Stowell, E Z; Deming, A F

    1936-01-01

    The two-blade propeller, one of the most powerful sources of sound known, has been studied with the view of obtaining fundamental information concerning the noise emission. In order to eliminate engine noise, the propeller was mounted on an electric motor. A microphone was used to pick up the sound whose characteristics were studied electrically. The distribution of noise throughout the frequency range, as well as the spatial distribution about the propeller, was studied. The results are given in the form of polar diagrams. An appendix of common acoustical terms is included.

  10. Experimental Research on Air Propellers III

    Science.gov (United States)

    Durand, W F; Lesley, E P

    1920-01-01

    Report presents the results of wind tunnel tests of propellers that examined the influence of the following characteristics: (1) nominal pitch ratio 1.3 combined with a certain number of the more common or standard forms and proportions; (2) driving face slightly rounded or convex; (3) change in the location of the maximum thickness ordinate of the blade section; (4) pushing forward the leading edge of the blade, thus giving a rounded convex surface on the leading side of the driving face. (5) a series of values for the constant "angle of attack" in forming propellers with radially increasing pitch. In accordance with these purposes tests were carried out on 28 propellers.

  11. Shuttle APS propellant thermal conditioner study

    Science.gov (United States)

    Pearson, W. E.

    1971-01-01

    A study program was performed to allow selection of thermal conditioner assemblies for superheating O2 and H2 at supercritical pressures. The application was the auxiliary propulsion system (APS) for the space shuttle vehicle. The O2/H2 APS propellant feed system included propellant conditioners, of which the thermal conditioner assemblies were a part. Cryogens, pumped to pressures above critical, were directed to the thermal conditioner assembly included: (1) a gas generator assembly with ignition system and bipropellant valves, which burned superheated O2 and H2 at rich conditions; (2) a heat exchanger assembly for thermal conditioning of the cryogenic propellant; and (3) a dump nozzle for heat exchanger exhaust.

  12. Removal of Pb(II) from wastewater using Al2O3-NaA zeolite composite hollow fiber membranes synthesized from solid waste coal fly ash.

    Science.gov (United States)

    Zhu, Li; Ji, Jiayou; Wang, Shulin; Xu, Chenxi; Yang, Kun; Xu, Man

    2018-09-01

    Al 2 O 3 -NaA zeolite composite hollow fiber membranes were successfully fabricated via hydrothermal synthesis by using industrial solid waste coal fly ash and porous Al 2 O 3 hollow fiber supports. The as-synthesized Al 2 O 3 -NaA zeolite composite hollow fiber membranes were then characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The hollow fiber membranes were used to remove lead ions (Pb(II), 50 mg L -1 ) from synthetic wastewater with a removal efficiency of 99.9% at 0.1 MPa after 12 h of filtration. This study showed that the Al 2 O 3 -NaA zeolite composite hollow fiber membranes (the pore size of the membrane was about 0.41 nm in diameter) synthesized from coal fly ash could be efficiently used for treating low concentration Pb(II) wastewater. It recycled solid waste coal fly ash not only to solve its environment problems, but also can produce high-value Al 2 O 3 -NaA zeolite composite hollow fiber membranes for separation application in treating wastewater containing Pb(II). Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Electrophoretic deposition of 9-YSZ solid electrolyte on Ni- YSZ composite; Estudos de deposicao eletroforetica de ceramicas de 9-YSZ sobre Ni-YSZ

    Energy Technology Data Exchange (ETDEWEB)

    Santos, F.S.; Yoshito, W.K.; Lazar, D.R.R.; Ussui, V., E-mail: vussui@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (CCTM/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Ciencia e Tecnologia de Materiais

    2010-07-01

    9-YSZ ceramic and Ni-YSZ metal/ceramic composite are the more commonly used materials for the fabrication of solid oxide fuel cell electrolyte and anode, respectively. The main challenges for these applications are the forming of both materials as superposed double thin layers. In the present work ceramic powder of 9- YSZ was synthesized by a coprecipitation technique and the Ni O-YSZ composite by a combustion technique. The later was formed by uniaxial pressing as cylindrical pellets of 15 mm diameter. Thin ceramic layers of 9-YSZ were deposited on composite pellets from a suspension with 10% solid content by an Electrophoretic Deposition technique. Applied voltage varied in the range of 30 to 200 V and deposition time from 15 to 90 seconds, evaluating the deposited mass, porosity on the interface and adhesion of layers. Resulted ceramics were characterized by X-ray diffraction and were observed in a scanning electron microscope. Results showed that deposited layers are thin ({approx}20{mu}m), dense and have good adhesion on the surface of composite substrate. (author)

  14. Analysis of Aerodynamic Load of LSU-03 (LAPAN Surveillance UAV-03) Propeller

    Science.gov (United States)

    Rahmadi Nuranto, Awang; Jamaludin Fitroh, Ahmad; Syamsudin, Hendri

    2018-04-01

    The existing propeller of the LSU-03 aircraft is made of wood. To improve structural strength and obtain better mechanical properties, the propeller will be redesigned usingcomposite materials. It is necessary to simulate and analyze the design load. This research paper explainsthe simulation and analysis of aerodynamic load prior to structural design phase of composite propeller. Aerodynamic load calculations are performed using both the Blade Element Theory(BET) and the Computational Fluid Dynamic (CFD)simulation. The result of both methods show a close agreement, the different thrust forces is only 1.2 and 4.1% for two type mesh. Thus the distribution of aerodynamic loads along the surface of the propeller blades of the 3-D CFD simulation results are considered valid and ready to design the composite structure. TheCFD results is directly imported to the structure model using the Direct Import CFD / One-Way Fluid Structure Interaction (FSI) method. Design load of propeller is chosen at the flight condition at speed of 20 km/h at 7000 rpm.

  15. 14 CFR 35.23 - Propeller control system.

    Science.gov (United States)

    2010-01-01

    ... propeller effect under the intended operating conditions. (4) The failure or corruption of data or signals... corruption of airplane-supplied data does not result in hazardous propeller effects. (e) The propeller... effect. (2) Failures or malfunctions directly affecting the propeller control system in a typical...

  16. Form-stable paraffin/high density polyethylene composites as solid-liquid phase change material for thermal energy storage: preparation and thermal properties

    International Nuclear Information System (INIS)

    Sari, Ahmet

    2004-01-01

    This paper deals with the preparation of paraffin/high density polyethylene (HDPE) composites as form-stable, solid-liquid phase change material (PCM) for thermal energy storage and with determination of their thermal properties. In such a composite, the paraffin (P) serves as a latent heat storage material and the HDPE acts as a supporting material, which prevents leakage of the melted paraffin because of providing structural strength. Therefore, it is named form-stable composite PCM. In this study, two kinds of paraffins with melting temperatures of 42-44 deg. C (type P1) and 56-58 deg. C (type P2) and latent heats of 192.8 and 212.4 J g -1 were used. The maximum weight percentage for both paraffin types in the PCM composites without any seepage of the paraffin in the melted state were found as high as 77%. It is observed that the paraffin is dispersed into the network of the solid HDPE by investigation of the structure of the composite PCMs using a scanning electronic microscope (SEM). The melting temperatures and latent heats of the form-stable P1/HDPE and P2/HDPE composite PCMs were determined as 37.8 and 55.7 deg. C, and 147.6 and 162.2 J g -1 , respectively, by the technique of differential scanning calorimetry (DSC). Furthermore, to improve the thermal conductivity of the form-stable P/HDPE composite PCMs, expanded and exfoliated graphite (EG) by heat treatment was added to the samples in the ratio of 3 wt.%. Thereby, the thermal conductivity was increased about 14% for the form-stable P1/HDPE and about 24% for the P2/HDPE composite PCMs. Based on the results, it is concluded that the prepared form-stable P/HDPE blends as composite type PCM have great potential for thermal energy storage applications in terms of their satisfactory thermal properties and improved thermal conductivity. Furthermore, these composite PCMs added with EG can be considered cost effective latent heat storage materials since they do not require encapsulation and extra cost to enhance

  17. Development and implementation of a propeller test capability for GL-10 "Greased Lightning" propeller design

    Science.gov (United States)

    Duvall, Brian Edward

    Interest in small unmanned aerial vehicles has increased dramatically in recent years. Hybrid vehicles which allow forward flight as a fixed wing aircraft and a true vertical landing capability have always had applications. Management of the available energy and noise associated with electric propeller propulsion systems presents many challenges. NASA Langley has developed the Greased Lightning 10 (GL-10) vertical takeoff, unmanned aerial vehicle with ten individual motors and propellers. All are used for propulsion during takeoff and contribute to acoustic noise pollution which is an identified nuisance to the surrounding users. A propeller test capability was developed to gain an understanding of how the noise can be reduced while meeting minimum thrust requirements. The designed propeller test stand allowed for various commercially available propellers to be tested for potential direct replacement of the current GL-10 propellers and also supported testing of a newly designed propeller provided by the Georgia Institute of Technology. Results from the test program provided insight as to which factors affect the noise as well as performance characteristics. The outcome of the research effort showed that the current GL-10 propeller still represents the best choice of all the candidate propellers tested.

  18. Alternate Propellant Thermal Rocket, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Alternate Propellant Thermal Rocket (APTR) is a novel concept for propulsion of space exploration or orbit transfer vehicles. APTR propulsion is provided by...

  19. The PROPEL Electrodynamic Tether Demonstration Mission

    Science.gov (United States)

    Bilen, Sven G.; Johnson, C. Les; Wiegmann, Bruce M.; Alexander, Leslie; Gilchrist, Brian E.; Hoyt, Robert P.; Elder, Craig H.; Fuhrhop, Keith P.; Scadera, Michael

    2012-01-01

    The PROPEL ("Propulsion using Electrodynamics") mission will demonstrate the operation of an electrodynamic tether propulsion system in low Earth orbit and advance its technology readiness level for multiple applications. The PROPEL mission has two primary objectives: first, to demonstrate the capability of electrodynamic tether technology to provide robust and safe, near-propellantless propulsion for orbit-raising, de-orbit, plane change, and station keeping, as well as to perform orbital power harvesting and formation flight; and, second, to fully characterize and validate the performance of an integrated electrodynamic tether propulsion system, qualifying it for infusion into future multiple satellite platforms and missions with minimal modification. This paper provides an overview of the PROPEL system and design reference missions; mission goals and required measurements; and ongoing PROPEL mission design efforts.

  20. In-Space Manufacture of Storable Propellants

    Data.gov (United States)

    National Aeronautics and Space Administration — Many deep-space, missions, especially those that return material or crews to near-Earth space, are severely limited by the need to carry propellants and heat shields...

  1. Nuclear thermal rockets using indigenous Martian propellants

    International Nuclear Information System (INIS)

    Zubrin, R.M.

    1989-01-01

    This paper considers a novel concept for a Martian descent and ascent vehicle, called NIMF (for nuclear rocket using indigenous Martian fuel), the propulsion for which will be provided by a nuclear thermal reactor which will heat an indigenous Martian propellant gas to form a high-thrust rocket exhaust. The performance of each of the candidate Martian propellants, which include CO2, H2O, CH4, N2, CO, and Ar, is assessed, and the methods of propellant acquisition are examined. Attention is also given to the issues of chemical compatibility between candidate propellants and reactor fuel and cladding materials, and the potential of winged Mars supersonic aircraft driven by this type of engine. It is shown that, by utilizing the nuclear landing craft in combination with a hydrogen-fueled nuclear thermal interplanetary vehicle and a heavy lift booster, it is possible to achieve a manned Mars mission in one launch. 6 refs

  2. Propeller performance analysis using lifting line theory

    OpenAIRE

    Flood, Kevin M.

    2009-01-01

    CIVINS (Civilian Institutions) Thesis document Approved for public release ; distribution is unlimited Propellers are typically optimized to provide the maximum thrust for the minimum torque at a specific number of revolutions per minute (RPM) at a particular ship speed. This process allows ships to efficiently travel at their design speed. However, it is useful to know how the propeller performs during off-design conditions. This is especially true for naval warships whose missions req...

  3. Potential low cost, safe, high efficiency propellant for future space program

    Science.gov (United States)

    Zhou, D.

    2005-03-01

    Mixtures of nanometer or micrometer sized carbon powder suspended in hydrogen and methane/hydrogen mixtures are proposed as candidates for low cost, high efficiency propellants for future space programs. While liquid hydrogen has low weight and high heat of combustion per unit mass, because of the low mass density the heat of combustion per unit volume is low, and the liquid hydrogen storage container must be large. The proposed propellants can produce higher gross heat combustion with small volume with trade off of some weight increase. Liquid hydrogen can serve as the fluid component of the propellant in the mixtures and thus used by current rocket engine designs. For example, for the same volume a mixture of 5% methane and 95% hydrogen, can lead to an increase in the gross heat of combustion by about 10% and an increase in the Isp (specific impulse) by 21% compared to a pure liquid hydrogen propellant. At liquid hydrogen temperatures of 20.3 K, methane will be in solid state, and must be formed as fine granules (or slush) to satisfy the requirement of liquid propellant engines.

  4. HMX based enhanced energy LOVA gun propellant

    Energy Technology Data Exchange (ETDEWEB)

    Sanghavi, R.R. [High Energy Materials Research Laboratory, Pune 411021 (India)]. E-mail: sanghavirr@yahoo.co.uk; Kamale, P.J. [High Energy Materials Research Laboratory, Pune 411021 (India); Shaikh, M.A.R. [High Energy Materials Research Laboratory, Pune 411021 (India); Shelar, S.D. [High Energy Materials Research Laboratory, Pune 411021 (India); Kumar, K. Sunil [High Energy Materials Research Laboratory, Pune 411021 (India); Singh, Amarjit [High Energy Materials Research Laboratory, Pune 411021 (India)

    2007-05-08

    Efforts to develop gun propellants with low vulnerability have recently been focused on enhancing the energy with a further improvement in its sensitivity characteristics. These propellants not only prevent catastrophic disasters due to unplanned initiation of currently used gun propellants (based on nitrate esters) but also realize enhanced energy levels to increase the muzzle velocity of the projectiles. Now, in order to replace nitroglycerine, which is highly sensitive to friction and impact, nitramines meet the requirements as they offer superior energy due to positive heat of formation, typical stoichiometry with higher decomposition temperatures and also owing to negative oxygen balance are less sensitive than stoichiometrically balanced NG. RDX has been widely reported for use in LOVA propellant. In this paper we have made an effort to present the work on scantily reported nitramine HMX based LOVA gun propellant while incorporating energetic plasticizer glycidyl azide polymer to enhance the energy level. HMX is known to be thermally stable at higher temperature than RDX and also proved to be less vulnerable to small scale shaped charge jet attack as its decomposition temperature is 270 deg. C. HMX also offers improved impulse due to its superior heat of formation (+17 kcal/mol) as compared to RDX (+14 kcal/mol). It has also been reported that a break point will not appear until 35,000 psi for propellant comprising of 5 {mu}m HMX. Since no work has been reported in open literature regarding replacement of RDX by HMX, the present studies were carried out.

  5. Propeller installation effects on turboprop aircraft acoustics

    Science.gov (United States)

    Chirico, Giulia; Barakos, George N.; Bown, Nicholas

    2018-06-01

    Propeller installation options for a twin-engined turboprop aircraft are evaluated at cruise conditions, aiming to identify the quieter configuration. Computational fluid dynamics is used to investigate the near-field acoustics and transfer functions are employed to estimate the interior cabin noise. Co-rotating and counter-rotating installation options are compared. The effect of propeller synchrophasing is also considered. The employed method captures the complexity of the acoustic field generated by the interactions of the propeller sound fields among each other and with the airframe, showing also the importance of simulating the whole problem to predict the actual noise on a flying aircraft. Marked differences among the various layouts are observed. The counter-rotating top-in option appears the best in terms of acoustics, the top-out propeller rotation leading to louder noise because of inflow conditions and the occurrence of constructive acoustic interferences. Synchrophasing is shown to be beneficial for co-rotating propellers, specially regarding the interior noise, because of favorable effects in the interaction between the propeller direct sound field and the noise due to the airframe. An angle closer to the maximum relative blade shift was found to be the best choice, yielding, however, higher sound levels than those provided by the counter-rotating top-in layout.

  6. Materials space of solid-state electrolytes: unraveling chemical composition-structure-ionic conductivity relationships in garnet-type metal oxides using cheminformatics virtual screening approaches.

    Science.gov (United States)

    Kireeva, Natalia; Pervov, Vladislav S

    2017-08-09

    The organic electrolytes of most current commercial rechargeable Li-ion batteries (LiBs) are flammable, toxic, and have limited electrochemical energy windows. All-solid-state battery technology promises improved safety, cycling performance, electrochemical stability, and possibility of device miniaturization and enables a number of breakthrough technologies towards the development of new high power and energy density microbatteries for electronics with low processing cost, solid oxide fuel cells, electrochromic devices, etc. Currently, rational materials design is attracting significant attention, which has resulted in a strong demand for methodologies that can accelerate the design of materials with tailored properties; cheminformatics can be considered as an efficient tool in this respect. This study was focused on several aspects: (i) identification of the parameters responsible for high Li-ion conductivity in garnet structured oxides; (ii) development of quantitative models to elucidate composition-structure-Li ionic conductivity relationships, taking into account the experimental details of sample preparation; (iii) circumscription of the materials space of solid garnet-type electrolytes, which is attractive for virtual screening. Several candidate compounds have been recommended for synthesis as potential solid state electrolyte materials.

  7. Solid phase microbial fuel cell (SMFC) for harnessing bioelectricity from composite food waste fermentation: influence of electrode assembly and buffering capacity.

    Science.gov (United States)

    Mohan, S Venkata; Chandrasekhar, K

    2011-07-01

    Solid phase microbial fuel cells (SMFC; graphite electrodes; open-air cathode) were designed to evaluate the potential of bioelectricity production by stabilizing composite canteen based food waste. The performance was evaluated with three variable electrode-membrane assemblies. Experimental data depicted feasibility of bioelectricity generation from solid state fermentation of food waste. Distance between the electrodes and presence of proton exchange membrane (PEM) showed significant influence on the power yields. SMFC-B (anode placed 5 cm from cathode-PEM) depicted good power output (463 mV; 170.81 mW/m(2)) followed by SMFC-C (anode placed 5 cm from cathode; without PEM; 398 mV; 53.41 mW/m(2)). SMFC-A (PEM sandwiched between electrodes) recorded lowest performance (258 mV; 41.8 mW/m(2)). Sodium carbonate amendment documented marked improvement in power yields due to improvement in the system buffering capacity. SMFCs operation also documented good substrate degradation (COD, 76%) along with bio-ethanol production. The operation of SMFC mimicked solid-sate fermentation which might lead to sustainable solid waste management practices. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Design of laser-driven SiO2-YAG:Ce composite thick film: Facile synthesis, robust thermal performance, and application in solid-state laser lighting

    Science.gov (United States)

    Xu, Jian; Liu, Bingguo; Liu, Zhiwen; Gong, Yuxuan; Hu, Baofu; Wang, Jian; Li, Hui; Wang, Xinliang; Du, Baoli

    2018-01-01

    In recent times, there have been rapid advances in the solid-state laser lighting technology. Due to the large amounts of heat accumulated from the high flux laser radiation, color conversion materials used in solid-state laser lighting devices should possess high durability, high thermal conductivity, and low thermal quenching. The aim of this study is to develop a thermally robust SiO2-YAG:Ce composite thick film (CTF) for high-power solid-state laser lighting applications. Commercial colloidal silica which was used as the source of SiO2, played the roles of an adhesive, a filler, and a protecting agent. Compared to the YAG:Ce powder, the CTF exhibits remarkable thermal stability (11.3% intensity drop at 200 °C) and durability (4.5% intensity drop after 1000 h, at 85 °C and 85% humidity). Furthermore, the effects of the substrate material and the thickness of the CTF on the laser lighting performance were investigated in terms of their thermal quenching and luminescence saturation behaviors, respectively. The CTF with a thickness of 50 μm on a sapphire substrate does not show luminescence saturation, despite a high-power density of incident radiation i.e. 20 W/mm2. These results demonstrate the potential applicability of the CTF in solid-state laser lighting devices.

  9. Mechanism of formation of humus coatings on mineral surfaces 3. Composition of adsorbed organic acids from compost leachate on alumina by solid-state 13C NMR

    Science.gov (United States)

    Wershaw, R. L.; Llaguno, E.C.; Leenheer, J.A.

    1996-01-01

    The adsorption of compost leachate DOC on alumina is used as a model for elucidation of the mechanism of formation of natural organic coatings on hydrous metal oxide surfaces in soils and sediments. Compost leachate DOC is composed mainly of organic acid molecules. The solid-state 13C NMR spectra of these organic acids indicate that they are very similar in composition to aquatic humic substances. Changes in the solid-state 13C NMR spectra of compost leachate DOC fractions adsorbed on alumina indicate that the DOC molecules are most likely adsorbed on metal oxide surfaces through a combination of polar and hydrophobic interaction mechanisms. This combination of polar and hydrophobic mechanism leads to the formation of bilayer coatings of the leachate molecules on the oxide surfaces.

  10. Cavitation noise studies on marine propellers

    Science.gov (United States)

    Sharma, S. D.; Mani, K.; Arakeri, V. H.

    1990-04-01

    Experimental observations are described of cavitation inception and noise from five model propellers, three basic and two modified, tested in the open jet section of the Indian Institute of Science high-speed water tunnel facility. Extensive experiments on the three basic propellers of different design, which included visualization of cavitation and measurements of noise, showed that the dominant type of cavitation was in the form of tip vortex cavitation, accompanied by leading edge suction side sheet cavitation in its close vicinity, and the resultant noise depended on parameters such as the advance coefficient, the cavitation number, and the propeller geometry. Of these, advance coefficient was found to have the maximum influence not only on cavitation noise but also on the inception of cavitation. Noise levels and frequencies of spectra obtained from all the three basic propellers at conditions near inception and different advance coefficient values, when plotted in the normalized form as suggested by Blake, resulted in a universal spectrum which would be useful for predicting cavitation noise at prototype scales when a limited extent of cavitation is expected in the same form as observed on the present models. In an attempt to delay the onset of tip vortex cavitation, the blades of two of the three basic propellers were modified by drilling small holes in the tip and leading edge areas. Studies on the modified propellers showed that the effectiveness of the blade modification was apparently stronger at low advance coefficient values and depended on the blade sectional profile. Measurements of cavitation noise indicated that the modification also improved the acoustic performance of the propellers as it resulted in a complete attenuation of the low-frequency spectral peaks, which were prominent with the basic propellers. In addition to the above studies, which were conducted under uniform flow conditions, one of the basic propellers was tested in the simulated

  11. Ca{sub 2−x}Li{sub 2x}GeO{sub 4} solid solutions. Chemical composition range and flux crystal growth

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, V.A. [N.I. Lobachevsky State University of Nizhni Novgorod, Nizhni Novgorod, 603950 (Russian Federation); Marychev, M.O., E-mail: marychev@yandex.ru [N.I. Lobachevsky State University of Nizhni Novgorod, Nizhni Novgorod, 603950 (Russian Federation); Andreev, P.V.; Lykov, V.A.; Faddeev, M.A. [N.I. Lobachevsky State University of Nizhni Novgorod, Nizhni Novgorod, 603950 (Russian Federation); Koseva, I. [Bulgarian Academy of Science, Institute of General and Inorganic Chemistry, BU-1113 Sofia (Bulgaria); Nikolov, V. [N.I. Lobachevsky State University of Nizhni Novgorod, Nizhni Novgorod, 603950 (Russian Federation)

    2015-11-01

    A series of Ca{sub 2−x}Li{sub 2x}GeO{sub 4} specimens with 0 < 2x < 2, were synthesized by the classical solid state method. X-ray analysis revealed that for 0 < 2x < 0.6 only Ca{sub 2−x}Li{sub 2x}GeO{sub 4} solid solutions of Ca{sub 2}GeO{sub 4} structure crystallized. The cell parameters of these solid solutions linearly decreased upon increasing the lithium concentration, which means that the solutions are in accordance with the Vegard's law. For 2x > 0.6 the specimens contained two phases: (i) Ca{sub 2−x}Li{sub 2x}GeO{sub 4} solid solutions with maximum lithium concentration approximately equal to that for 2x = 0.6 and minimum values of the cell parameters and (ii) Li{sub 2}CaGeO{sub 4} phase. Li{sub 2}O·MoO{sub 3}–Ca{sub 2}GeO{sub 4} high-temperature solutions were used to grow Ca{sub 2−x}Li{sub 2x}GeO{sub 4} solid solutions and Li{sub 2}CaGeO{sub 4} single crystals by the high temperature solution (flux) method. Li{sub 2}CaGeO{sub 4} crystals were grown in the concentration range 8–26 wt. % Ca{sub 2}GeO{sub 4} in the temperature range 830–980 °C. Crystals with chemical compositions of the Ca{sub 2−x}Li{sub 2x}GeO{sub 4} solid solutions with different Li concentrations were grown in the concentration range 26–40 wt. % Ca{sub 2}GeO{sub 4} in the temperature range 980–1090 °C. - Highlights: • Ca{sub 2−x}Li{sub 2x}GeO{sub 4} solid solutions are established for the first time. • The Li concentration range into the solutions is between 0 and 0.6. • The solid solutions are in accordance to Vegard's law. • Suitable solutions are found out for Ca{sub 2−x}Li{sub 2x}GeO{sub 4} and Li{sub 2}CaGeO{sub 4} crystal growth.

  12. Wood composites

    Science.gov (United States)

    Lars Berglund; Roger M. Rowell

    2005-01-01

    A composite can be defined as two or more elements held together by a matrix. By this definition, what we call “solid wood” is a composite. Solid wood is a three-dimensional composite composed of cellulose, hemicelluloses and lignin (with smaller amounts of inorganics and extractives), held together by a lignin matrix. The advantages of developing wood composites are (...

  13. Composition

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2014-01-01

    Cue Rondo is an open composition to be realised by improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". Caution: streaming the sound/video files will in some cases only provide a few minutes' sample, or the visuals will not appear at all....... Please DOWNLOAD them to see/hear them in full length! This work is licensed under a Creative Commons "by-nc" License. You may for non-commercial purposes use and distribute it, performance instructions as well as specially designated recordings, as long as the author is mentioned. Please see http...

  14. Propeller and inflow vortex interaction : vortex response and impact on the propeller performance

    NARCIS (Netherlands)

    Yang, Y.; Zhou, T; Sciacchitano, A.; Veldhuis, L.L.M.; Eitelberg, G.

    2016-01-01

    The aerodynamic operating conditions of a propeller can include complex situations where vorticity from sources upstream can enter the propeller plane. In general, when the vorticity enters in a concentrated form of a vortex, the interaction between the vortex and blade is referred to as

  15. Polarization characteristics of composite electrodes in electrochemical cells with solid electrolytes based on CeO2 and LaGaO3

    International Nuclear Information System (INIS)

    Yaroslavtsev, I. Yu.; Kuzin, B. L.; Bronin, D. I.; Bogdanovich, N. M.

    2005-01-01

    For two types of electrochemical cells with oxygen-conducting solid electrolytes based on lanthanum gallate (LSGM) and cerium oxide (SDC) studied are the temperature dependences of the polarization conductivity of air electrodes prepared from lanthanum strontium manganite (LSM) and composites LSM-LSGM, LSM-SDC, and LSM-SSZ (SSZ is zirconium dioxide-based electrolyte). Effect of praseodymium oxide, added into these electrodes as a modifier, on their electrochemical properties is examined. Electrochemical systems with an LSM/LSGM interface exhibit low electrochemical activity toward the oxygen reaction, because during the formation of electrodes, LSM interacts with LSGM to form a poorly conducting product [ru

  16. Solid state electrolyte composites based on complex hydrides and metal doped fullerenes/fulleranes for batteries and electrochemical applications

    Science.gov (United States)

    Zidan, Ragaiy; Teprovich, Jr., Joseph A.; Colon-Mercado, Hector R.; Greenway, Scott D.

    2018-05-01

    A LiBH4--C60 nanocomposite that displays fast lithium ionic conduction in the solid state is provided. The material is a homogenous nanocomposite that contains both LiBH4 and a hydrogenated fullerene species. In the presence of C60, the lithium ion mobility of LiBH4 is significantly enhanced in the as prepared state when compared to pure LiBH4. After the material is annealed the lithium ion mobility is further enhanced. Constant current cycling demonstrated that the material is stable in the presence of metallic lithium electrodes. The material can serve as a solid state electrolyte in a solid-state lithium ion battery.

  17. Kinematic matrix theory and universalities in self-propellers and active swimmers.

    Science.gov (United States)

    Nourhani, Amir; Lammert, Paul E; Borhan, Ali; Crespi, Vincent H

    2014-06-01

    We describe an efficient and parsimonious matrix-based theory for studying the ensemble behavior of self-propellers and active swimmers, such as nanomotors or motile bacteria, that are typically studied by differential-equation-based Langevin or Fokker-Planck formalisms. The kinematic effects for elementary processes of motion are incorporated into a matrix, called the "kinematrix," from which we immediately obtain correlators and the mean and variance of angular and position variables (and thus effective diffusivity) by simple matrix algebra. The kinematrix formalism enables us recast the behaviors of a diverse range of self-propellers into a unified form, revealing universalities in their ensemble behavior in terms of new emergent time scales. Active fluctuations and hydrodynamic interactions can be expressed as an additive composition of separate self-propellers.

  18. Thermal Vacuum Test Correlation of a Zero Propellant Load Case Thermal Capacitance Propellant Gauging Analytical Model

    Science.gov (United States)

    Mckim, Stephen A.

    2016-01-01

    This thesis describes the development and correlation of a thermal model that forms the foundation of a thermal capacitance spacecraft propellant load estimator. Specific details of creating the thermal model for the diaphragm propellant tank used on NASA's Magnetospheric Multiscale spacecraft using ANSYS and the correlation process implemented are presented. The thermal model was correlated to within plus or minus 3 degrees Celsius of the thermal vacuum test data, and was determined sufficient to make future propellant predictions on MMS. The model was also found to be relatively sensitive to uncertainties in applied heat flux and mass knowledge of the tank. More work is needed to improve temperature predictions in the upper hemisphere of the propellant tank where predictions were found to be 2 to 2.5 C lower than the test data. A road map for applying the model to predict propellant loads on the actual MMS spacecraft toward its end of life in 2017-2018 is also presented.

  19. On Nonlinear Combustion Instability in Liquid Propellant Rocket Motors

    Science.gov (United States)

    Sims, J. D. (Technical Monitor); Flandro, Gary A.; Majdalani, Joseph; Sims, Joseph D.

    2004-01-01

    All liquid propellant rocket instability calculations in current use have limited value in the predictive sense and serve mainly as a correlating framework for the available data sets. The well-known n-t model first introduced by Crocco and Cheng in 1956 is still used as the primary analytical tool of this type. A multitude of attempts to establish practical analytical methods have achieved only limited success. These methods usually produce only stability boundary maps that are of little use in making critical design decisions in new motor development programs. Recent progress in understanding the mechanisms of combustion instability in solid propellant rockets"' provides a firm foundation for a new approach to prediction, diagnosis, and correction of the closely related problems in liquid motor instability. For predictive tools to be useful in the motor design process, they must have the capability to accurately determine: 1) time evolution of the pressure oscillations and limit amplitude, 2) critical triggering pulse amplitude, and 3) unsteady heat transfer rates at injector surfaces and chamber walls. The method described in this paper relates these critical motor characteristics directly to system design parameters. Inclusion of mechanisms such as wave steepening, vorticity production and transport, and unsteady detonation wave phenomena greatly enhance the representation of key features of motor chamber oscillatory behavior. The basic theoretical model is described and preliminary computations are compared to experimental data. A plan to develop the new predictive method into a comprehensive analysis tool is also described.

  20. Solid-state synthesis of uniform Li2MnSiO4/C/graphene composites and their performance in lithium-ion batteries

    Science.gov (United States)

    Gong, Huaxu; Zhu, Yongchun; Wang, Linlin; Wei, Denghu; Liang, Jianwen; Qian, Yitai

    2014-01-01

    Uniform nanospherical Li2MnSiO4/C/graphene composites have been obtained by polyethylene glycol-600 (PEG-600) assisted solid-state reaction using spherical SiO2 as precursor, and heat treatment with the mixed carbon sources (glucose, cellulose acetate and graphene oxide). The transmission electron microscope (TEM) images show that Li2MnSiO4 nanospheres with size of 50 nm are embedded in the three-dimensional (3D) nest-like carbon network. Electrochemical measurements reveal that the composites exhibit first discharge capacity of 215.3 mAh g-1 under 0.05 C, together with a stable discharge capacity of 175 mAh g-1 after 40 cycles. The 3D carbon network and the carbon layer (amorphous carbon and graphene) are favorable for improving the electrochemical performance.

  1. The solid-liquid extraction separation of lithium isotopes by porous composite materials doped with ionic liquids and 2,2'-binaphthyldiyl-17-crown-5

    International Nuclear Information System (INIS)

    Xiao-Li Sun; Ling Gu; Dan Qiu; Dong-Hong Ren; Zaijun Li; Zhi-Guo Gu; Jiangnan University, Wuxi

    2015-01-01

    A green and efficient solid-liquid extraction method of lithium isotopes separation by porous composite materials doped with imidazolium ionic liquids and 2,2'-binaphthyldiyl-17-crown-5 has been reported in this paper. The composite materials of mesoporous silica and impregnated resin were synthesized by sol-gel and direct impregnation process, respectively. Various extraction parameters such as the concentration of lithium salt, anion of lithium salt, initial pH, time and temperature were investigated. Under optimized conditions, the maximum single-stage separation factor of 6 Li/ 7 Li was 1.048 ± 0.002, the maximum extraction efficiency was 15.86 %. The sorbents can be regenerated easily with HCl solution and reused repeatedly. (author)

  2. Quasi Solid-State Dye-Sensitized Solar Cell Incorporating Highly Conducting Polythiophene-Coated Carbon Nanotube Composites in Ionic Liquid

    Directory of Open Access Journals (Sweden)

    Mohammad Rezaul Karim

    2011-01-01

    Full Text Available Conducting polythiophene (PTh composites with the host filler multiwalled carbon nanotube (MWNT have been used, for the first time, in the dye-sensitized solar cells (DSCs. A quasi solid-state DSCs with the hybrid MWNT-PTh composites, an ionic liquid of 1-methyl-3-propyl imidazolium iodide (PMII, was placed between the dye-sensitized porous TiO2 and the Pt counter electrode without adding iodine and higher cell efficiency (4.76% was achieved, as compared to that containing bare PMII (0.29%. The MWNT-PTh nanoparticles are exploited as the extended electron transfer materials and serve simultaneously as catalyst for the electrochemical reduction of I−3.

  3. Research on the combustion properties of propellants with low content of nano metal powders

    Energy Technology Data Exchange (ETDEWEB)

    Zhi, Jiang; Shu-Fen, Li [Department of Chemical Physics, University of Science and Technology of China, Hefei 230026 (China); Feng-Qi, Zhao; Zi-Ru, Liu; Cui-Mei, Yin; Yang, Luo; Shang-Wen, Li [Xi' an Modern Chemistry Research Inst., Xi' an 710065 (China)

    2006-04-15

    A comparison of various experimental results for combustionrelated properties evaluation, including burning rates, deflagration heat, flame structures and thermal decomposition properties, of AP/RDX/Al/HTPB composite propellants containing nano metal powders is presented. The thermal behavior of n-Al (nano grain size aluminum) and g-Al (general grain size aluminum i.e., 10 {mu}m) heated in air was also investigated by thermogravimetry. The burning rates results indicate that the usage of bimodal aluminum distribution with the ratio around 4: 1 of n-Al to g-Al or the addition of 2% nano nickel powders (n-Ni) will improve the burning behavior of the propellant, while the usage of grading aluminum powders with the ratio 1: 1 of n-Al to g-Al will impair the combustion of the propellant. Results show that n-Al and n-Ni both have a lower heating capacity, lower ignition threshold and shorter combustion time than g-Al. In addition n-Al is inclined to burn in single particle form. And the thermal analysis results show that n-Ni can catalyze the thermal decomposition of AP in the propellant. The results also confirm the high reactivity of n-Al, which will lead to a lower reaction temperature and rather higher degree of reaction ratio as compared with g-Al in air. All these factors will influence the combustion of propellants. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  4. High temperature tribological behaviors of (WAl)C–Co ceramic composites with the additions of fluoride solid lubricants

    International Nuclear Information System (INIS)

    Cheng, Jun; Qiao, Zhuhui; Yin, Bing; Hao, Junying; Yang, Jun; Liu, Weimin

    2015-01-01

    The tribological behaviors of the (W 0.67 Al 0.33 )C 0.67 –Co/fluoride (CaF 2 , BaF 2 , CaF 2 /BaF 2 ) composites against SiC ball from room temperature to 600 °C were investigated. A marked increase in the friction coefficient resulting from fluoride oxidation was observed as the temperature increased. The composites containing BaF 2 or (Ca, Ba)F 2 displayed better integrated wear resistance over a wide temperature range compared with (W 0.67 Al 0.33 )C 0.67 –Co/CaF 2 . The high temperature tribological characteristics of the three composites were distinct, which originated from the composition difference on the worn surfaces. First, the SiO 2 /SiC film formed on the worn surfaces of the composites with BaF 2 or (Ca, Ba)F 2 was favorable for their wear resistance. Second, the oxidation of WC matrix was an important factor influencing the wear resistance of the composites. When mixture oxides of WO 2 and WO 3 appeared on the surface, wear is severe. In addition, single WO 3 formed on the worn surfaces, appeared more adhesive to the underlying substrate and decreased the wear rate. - Highlights: • The composites containing BaF 2 or (Ca, Ba)F 2 exhibit better wear resistance. • The tribological behaviors are strongly correlated to surface composition. • The stoichiometry difference in the tungsten oxides leads to distinct wear rate. • The friction coefficient of the composites increases with the testing temperature

  5. High temperature tribological behaviors of (WAl)C–Co ceramic composites with the additions of fluoride solid lubricants

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Jun; Qiao, Zhuhui, E-mail: zhqiao@licp.cas.cn; Yin, Bing; Hao, Junying, E-mail: jyhao@licp.cas.cn; Yang, Jun; Liu, Weimin

    2015-08-01

    The tribological behaviors of the (W{sub 0.67}Al{sub 0.33})C{sub 0.67}–Co/fluoride (CaF{sub 2}, BaF{sub 2}, CaF{sub 2}/BaF{sub 2}) composites against SiC ball from room temperature to 600 °C were investigated. A marked increase in the friction coefficient resulting from fluoride oxidation was observed as the temperature increased. The composites containing BaF{sub 2} or (Ca, Ba)F{sub 2} displayed better integrated wear resistance over a wide temperature range compared with (W{sub 0.67}Al{sub 0.33})C{sub 0.67}–Co/CaF{sub 2}. The high temperature tribological characteristics of the three composites were distinct, which originated from the composition difference on the worn surfaces. First, the SiO{sub 2}/SiC film formed on the worn surfaces of the composites with BaF{sub 2} or (Ca, Ba)F{sub 2} was favorable for their wear resistance. Second, the oxidation of WC matrix was an important factor influencing the wear resistance of the composites. When mixture oxides of WO{sub 2} and WO{sub 3} appeared on the surface, wear is severe. In addition, single WO{sub 3} formed on the worn surfaces, appeared more adhesive to the underlying substrate and decreased the wear rate. - Highlights: • The composites containing BaF{sub 2} or (Ca, Ba)F{sub 2} exhibit better wear resistance. • The tribological behaviors are strongly correlated to surface composition. • The stoichiometry difference in the tungsten oxides leads to distinct wear rate. • The friction coefficient of the composites increases with the testing temperature.

  6. Chemical durability of slag produced by thermal plasma melting of low-level miscellaneous solid wastes. Effects of slag composition

    International Nuclear Information System (INIS)

    Amakawa, Tadashi; Yasui, Shinji

    2001-01-01

    Low-level radioactive miscellaneous solid wastes are generated from commercial operation of nuclear power plants and will be generated from decommissioning of nuclear power plants in future. Static leaching tests were carried out in deionized water of 10degC on slag obtained by thermal plasma melting of simulating materials of the miscellaneous solids wastes with surrogate elements of radionuclides. It is found that logarithm of normalized elemental mass loss from the slag is proportional to the basicity represented by mole fractions of main structural oxides of the slag, such as SiO 2 , Al 2 O 3 , CaO, FeO and MgO. The range of static leaching rates from the slag is determined based on the above results and the basicity range of the miscellaneous solid wastes. Then we compared the leaching rates form the slag and from high level waste glasses. On these grounds, we concluded that the slag obtained by thermal plasma melting of miscellaneous solid wastes can stabilize radio-nuclides in it by no means inferior to the high level waste glasses. (author)

  7. Phase Relations in Ternary Systems in the Subsolidus Region: Methods to Formulate Solid Solution Equations and to Find Particular Compositions

    Science.gov (United States)

    Alvarez-Montan~o, Victor E.; Farías, Mario H.; Brown, Francisco; Mun~oz-Palma, Iliana C.; Cubillas, Fernando; Castillon-Barraza, Felipe F.

    2017-01-01

    A good understanding of ternary phase diagrams is required to advance and/or to reproduce experimental research in solid-state and materials chemistry. The aim of this paper is to describe the solutions to problems that appear when studying or determining ternary phase diagrams. A brief description of the principal features shown in phase diagrams…

  8. Processing and characterization of solid and microcellular PHBV/PBAT blend and its RWF/nanoclay composites

    Science.gov (United States)

    Alireza Javadi; Yottha Srithep; Jungjoo Lee; Srikanth Pilla; Craig Clemons; Shaoqin Gong; Lih-Sheng Turng

    2010-01-01

    Solid and microcellular components made of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/ poly (butylenes adipate-co-terephthalate) (PBAT) blend (weight ration of PHBV:PBAT = 30:70), recycled wood fiber (RWF), and nanoclay (NC) were prepared via a conventional and microcellular-injection molding process, respectively. Morphology, thermal properties, and...

  9. Advances in LO2 Propellant Conditioning

    Science.gov (United States)

    Mehta, Gopal; Orth, Michael; Stone, William; Perry, Gretchen; Holt, Kimberly; Suter, John

    1994-01-01

    This paper describes the cryogenic testing and analysis that has recently been completed as part of a multi-year effort to develop a new, more robust and operable LO2 propellant conditioning system. Phase 1 of the program consisted of feasibility demonstrations ot four novel propellant conditioning concepts. A no-bleed, passive propellant conditioning option was shown for the first time to successfully provide desired propellant inlet conditions. The benefits of passive conditioning are reduced operations costs, decreased hardware costs, enhanced operability and increased reliability on future expendable launch vehicles In Phase 2 of the test program, effects of major design parameters were studied and design correlation for future vehicle design were developed. Simultaneously, analytical models were developed and validated. Over 100 tests were conducted with a full-scale feedline using LN2 as the test fluid. A circulation pump provided a range of pressure and flow conditions. The test results showed that the passive propellant conditioning system is insensitive to variations in many of the parameters. The test program provides the validation necessary to incorporate the passive conditioning system into the baseline of future vehicles. Modeling of these systems using computational fluid dynamics seems highly promising.

  10. In-Space Propellant Production Using Water

    Science.gov (United States)

    Notardonato, William; Johnson, Wesley; Swanger, Adam; McQuade, William

    2012-01-01

    A new era of space exploration is being planned. Manned exploration architectures under consideration require the long term storage of cryogenic propellants in space, and larger science mission directorate payloads can be delivered using cryogenic propulsion stages. Several architecture studies have shown that in-space cryogenic propulsion depots offer benefits including lower launch costs, smaller launch vehicles, and enhanced mission flexibility. NASA is currently planning a Cryogenic Propellant Storage and Transfer (CPST) technology demonstration mission that will use existing technology to demonstrate long duration storage, acquisition, mass gauging, and transfer of liquid hydrogen in low Earth orbit. This mission will demonstrate key technologies, but the CPST architecture is not designed for optimal mission operations for a true propellant depot. This paper will consider cryogenic propellant depots that are designed for operability. The operability principles considered are reusability, commonality, designing for the unique environment of space, and use of active control systems, both thermal and fluid. After considering these operability principles, a proposed depot architecture will be presented that uses water launch and on orbit electrolysis and liquefaction. This could serve as the first true space factory. Critical technologies needed for this depot architecture, including on orbit electrolysis, zero-g liquefaction and storage, rendezvous and docking, and propellant transfer, will be discussed and a developmental path forward will be presented. Finally, use of the depot to support the NASA Science Mission Directorate exploration goals will be presented.

  11. Characterisation of chemical composition and energy content of green waste and municipal solid waste from Greater Brisbane, Australia.

    Science.gov (United States)

    Hla, San Shwe; Roberts, Daniel

    2015-07-01

    The development and deployment of thermochemical waste-to-energy systems requires an understanding of the fundamental characteristics of waste streams. Despite Australia's growing interest in gasification of waste streams, no data are available on their thermochemical properties. This work presents, for the first time, a characterisation of green waste and municipal solid waste in terms of chemistry and energy content. The study took place in Brisbane, the capital city of Queensland. The municipal solid waste was hand-sorted and classified into ten groups, including non-combustibles. The chemical properties of the combustible portion of municipal solid waste were measured directly and compared with calculations made based on their weight ratios in the overall municipal solid waste. The results obtained from both methods were in good agreement. The moisture content of green waste ranged from 29% to 46%. This variability - and the tendency for soil material to contaminate the samples - was the main contributor to the variation of samples' energy content, which ranged between 7.8 and 10.7MJ/kg. The total moisture content of food wastes and garden wastes was as high as 70% and 60%, respectively, while the total moisture content of non-packaging plastics was as low as 2.2%. The overall energy content (lower heating value on a wet basis, LHVwb) of the municipal solid waste was 7.9MJ/kg, which is well above the World Bank-recommended value for utilisation in thermochemical conversion processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Fracture strength and failure mode of maxillary implant-supported provisional single crowns: a comparison of composite resin crowns fabricated directly over PEEK abutments and solid titanium abutments.

    Science.gov (United States)

    Santing, Hendrik Jacob; Meijer, Henny J A; Raghoebar, Gerry M; Özcan, Mutlu

    2012-12-01

    Polyetheretherketone (PEEK) temporary abutments have been recently introduced for making implant-supported provisional single crowns. Little information is available in the dental literature on the durability of provisional implant-supported restorations. The objectives of this study were to evaluate the fracture strength of implant-supported composite resin crowns on PEEK and solid titanium temporary abutments, and to analyze the failure types. Three types of provisional abutments, RN synOcta Temporary Meso Abutment (PEEK; Straumann), RN synOcta Titanium Post for Temporary Restorations (Straumann), and Temporary Abutment Engaging NobRplRP (Nobel Biocare) were used, and provisional screw-retained crowns using composite resin (Solidex) were fabricated for four different locations in the maxilla. The specimens were tested in a universal testing machine at a crosshead speed of 1 mm/minute until fracture occurred. The failure types were analyzed and further categorized as irreparable (Type 1) or reparable (Type 2). No significant difference was found between different abutment types. Only for the position of the maxillary central incisor, composite resin crowns on PEEK temporary abutments showed significantly lower (p Provisional crowns on PEEK abutments showed similar fracture strength as titanium temporary abutments except for central incisors. Maxillary right central incisor composite resin crowns on PEEK temporary abutments fractured below the mean anterior masticatory loading forces reported to be approximately 206 N. © 2010 Wiley Periodicals, Inc.

  13. Strong and anisotropic magnetoelectricity in composites of magnetostrictive Ni and solid-state grown lead-free piezoelectric BZT–BCT single crystals

    Directory of Open Access Journals (Sweden)

    Haribabu Palneedi

    2017-03-01

    Full Text Available Aimed at developing lead-free magnetoelectric (ME composites with performances as good as lead (Pb-based ones, this study employed (001 and (011 oriented 82BaTiO3-10BaZrO3-8CaTiO3 (BZT–BCT piezoelectric single crystals, fabricated by the cost-effective solid-state single crystal growth (SSCG method, in combination with inexpensive, magnetostrictive base metal Nickel (Ni. The off-resonance, direct ME coupling in the prepared Ni/BZT–BCT/Ni laminate composites was found to be strongly dependent on the crystallographic orientation of the BZT–BCT single crystals, as well as the applied magnetic field direction. Larger and anisotropic ME voltage coefficients were observed for the composite made using the (011 oriented BZT–BCT single crystal. The optimized ME coupling of 1 V/cm Oe was obtained from the Ni/(011 BZT–BCT single crystal/Ni composite, in the d32 mode of the single crystal, when a magnetic field was applied along its [100] direction. This performance is similar to that reported for the Ni/Pb(Mg1/3Nb2/3O3-Pb(Zr,TiO3 (PMN–PZT single crystal/Ni, but larger than that obtained from the Ni/Pb(Zr,TiO3 ceramic/Ni composites. The results of this work demonstrate that the use of lead-free piezoelectric single crystals with special orientations permits the selection of desired anisotropic properties, enabling the realization of customized ME effects in composites.

  14. Determination of solid surface composition by the X-ray fluorescence method under total external reflection with angular scanning

    International Nuclear Information System (INIS)

    Krasnolutskij, V.P.

    2000-01-01

    Possibilities of determination of composition of surface layers by X-ray fluorescence analysis under total reflection of incident radiation with angular scanning of a target are investigated. For the case of the GaAs target it is shown that the sensibility of this method is sufficient for a control of element composition in layer of thickness 1 nm. A simple method for solution of inverse task of analysis of a two component medium is considered [ru

  15. Facile synthesis of amorphous FeOOH/MnO2 composites as screen-printed electrode materials for all-printed solid-state flexible supercapacitors

    Science.gov (United States)

    Lu, Qiang; Liu, Li; Yang, Shuanglei; Liu, Jun; Tian, Qingyong; Yao, Weijing; Xue, Qingwen; Li, Mengxiao; Wu, Wei

    2017-09-01

    More convenience and intelligence life lead by flexible/wearable electronics requires innovation and hommization of power sources. Here, amorphous FeOOH/MnO2 composite as screen-printed electrode materials for supercapacitors (SCs) is synthesized by a facile method, and solid-state flexible SCs with aesthetic design are fabricated by fully screen-printed process on different substrates, including PET, paper and textile. The amorphous FeOOH/MnO2 composite shows a high specific capacitance and a good rate capability (350.2 F g-1 at a current density of 0.5 A g-1 and 159.5 F g-1 at 20 A g-1). It also possesses 95.6% capacitance retention even after 10 000 cycles. Moreover, the all-printed solid-state flexible SC device exhibits a high area specific capacitance of 5.7 mF cm-2 and 80% capacitance retention even after 2000 cycles. It also shows high mechanical flexibility. Simultaneously, these printed SCs on different substrates in series are capable to light up a 1.9 V yellow light emitting diode (LED), even after bending and stretching.

  16. Phosphorus Enrichment as a New Composition in the Solid Electrolyte Interphase of High-Voltage Cathodes and Its Effects on Battery Cycling

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Pengfei; Zheng, Jianming; Kuppan, Saravanan; Li, Qiuyan; Lv, Dongping; Xiao, Jie; Chen, Guoying; Zhang, Jiguang; Wang, Chong M.

    2015-11-10

    Immersion of a solid into liquid often leads to the modification of both the structure and chemistry of surface of the solid, which subsequently affects the chemical and physical properties of the system. For the case of the rechargeable lithium ion battery, such a surface modification is termed as solid electrolyte interphase (SEI) layer, which has been perceived to play critical role for the stable operation of the batteries. However, the structure and chemical composition of SEI layer and its spatial distribution and dependence on the battery operating condition remain unclear. By using aberration corrected scanning transmission electron microscopy coupled with ultra-high sensitive energy dispersive x-ray spectroscopy, we probed the structure and chemistry of SEI layer on several high voltage cathodes. We show that layer-structured cathodes, when cycled at a high cut off voltage, can form a P-rich SEI layer on their surface, which is a direct evidence of Li-salt (LiPF6) decomposition. Our systematical investigations indicate such cathode/Li-salt side reaction shows strong dependence on structure of the cathode materials, operating voltage and temperature, indicating the feasibility of SEI engineering. These findings provide us valuable insights into the complex interface between the high-voltage cathode and the electrolyte.

  17. Heterogeneous propellant internal ballistics: criticism and regeneration

    Science.gov (United States)

    Glick, R. L.

    2011-10-01

    Although heterogeneous propellant and its innately nondeterministic, chemically discrete morphology dominates applications, ballisticcharacterization deterministic time-mean burning rate and acoustic admittance measures' absence of explicit, nondeterministic information requires homogeneous propellant with a smooth, uniformly regressing burning surface: inadequate boundary conditions for heterogeneous propellant grained applications. The past age overcame this dichotomy with one-dimensional (1D) models and empirical knowledge from numerous, adequately supported motor developments and supplementary experiments. However, current cost and risk constraints inhibit this approach. Moreover, its fundamental science approach is more sensitive to incomplete boundary condition information (garbage-in still equals garbage-out) and more is expected. This work critiques this situation and sketches a path forward based on enhanced ballistic and motor characterizations in the workplace and approximate model and apparatus developments mentored by CSAR DNS capabilities (or equivalent).

  18. Temperature and compositional dependence of solid-liquid interfacial energy: application of the Cahn-Hilliard theory

    International Nuclear Information System (INIS)

    Shimizu, I.; Takei, Y.

    2005-01-01

    A simple thermodynamic method to estimate the solid-liquid interfacial energy (or interfacial tension) is proposed, based on the Cahn-Hilliard theory. In the model, the liquid is treated as a regular solution, and the interfacial layers are assumed to have liquid-like thermodynamic properties. In eutectic systems, interfacial adsorption occurs within a few atomic layers, and interfacial energy monotonously increases with decreasing concentration of the solid species in the liquid phase. If non-ideal atomic interaction is strong and the liquid immiscibility region appears in the phase diagrams (this is the case of monotectic systems), the interfacial thickness drastically increases and the interfacial energy is reduced around the immiscibility gap

  19. Study of solid rocket motor for space shuttle booster, volume 2, book 1

    Science.gov (United States)

    1972-01-01

    The technical requirements for the solid propellant rocket engine to be used with the space shuttle orbiter are presented. The subjects discussed are: (1) propulsion system definition, (2) solid rocket engine stage design, (3) solid rocket engine stage recovery, (4) environmental effects, (5) manrating of the solid rocket engine stage, (6) system safety analysis, and (7) ground support equipment.

  20. Ti2Al(C, N) Solid Solution Reinforcing TiAl-Based Composites: Evolution of a Core-Shell Structure, Interfaces, and Mechanical Properties.

    Science.gov (United States)

    Song, Xiaojie; Cui, Hongzhi; Han, Ye; Ding, Lei; Song, Qiang

    2018-05-16

    In this work, Ti 2 Al(C, N) solid solution with lamellar structure-enhanced TiAl matrix composites was synthesized by vacuum arc melting, using bulk g-C 3 N 4 , Ti, and Al powders as raw materials. The phases, microstructures, interfaces, and mechanical properties were investigated. MAX phase of Ti 2 Al(C, N) solid solution with lamellar structure was formed. During the melting process, first, C 3 N 4 reacted with Ti to form Ti(C, N) by Ti + C 3 N 4 → Ti(C, N). Then Ti 2 Al(C, N) was formed by a peritectic reaction of TiAl(l) + Ti(C, N)(s) → Ti 2 Al(C, N). C 3 N 4 is the single reactant that provides C and N simultaneously to final product of Ti 2 Al(C, N). The interfaces of TiAl//Ti 2 Al(C, N) and Ti 2 Al(C, N)//Ti(C, N) display perfect orientation relationships with low misfit values. The microhardness, compressive strength, and strain of best-performing TiAl-10 mol % Ti 2 Al(C, N) composite were improved by 45%, 55.7%, and 50% compared with the TiAl alloy, respectively. Uniformly distributed Ti 2 Al(C, N) and unreacted Ti(C, N) particles contributed to the grain refinement and reinforcement of the TiAl matrix. Laminated tearing, particle pull-out, and the crack-arresting of Ti 2 Al(C, N) are crucial for the improvement in compressive strength and plasticity of the composites.

  1. CFD simulation on Kappel propeller with a hull wake field

    DEFF Research Database (Denmark)

    Shin, Keun Woo; Andersen, Poul; Møller Bering, Rasmus

    2013-01-01

    Marine propellers are designed not for the open-water operation, but for the operation behind a hull due to the inhomogeneous hull wake and thrust deduction. The adaptation for the hull wake is important for the propulsive efficiency and cavitation risk especially on single-screw ships. CFD...... simulations for a propeller with a hull model have showed acceptable agreement with a model test result in the thrust and torque (Larsson et al. 2010). In the current work, a measured hull wake is applied to the simulation instead of modelling a hull, because the hull geometry is mostly not available...... for propeller designers and the computational effort can be reduced by excluding the hull. The CFD simulation of a propeller flow with a hull wake is verified in order to use CFD as a propeller design tool. A Kappel propeller, which is an innovative tip-modified propeller, is handled. Kappel propellers...

  2. Neural Network Predictions of the 4-Quadrant Wageningen Propeller Series

    National Research Council Canada - National Science Library

    Roddy, Robert F; Hess, David E; Faller, Will

    2006-01-01

    .... This report describes the development of feedforward neural network (FFNN) predictions of four-quadrant thrust and torque behavior for the Wageningen B-Screw Series of propellers and for two Wageningen ducted propeller series...

  3. Innovative Swirl Injector for LOX and Hydrocarbon Propellants, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Gases trapped in the propellant feed lines of space-based rocket engines due to cryogenic propellant boil-off or pressurant ingestion can result in poor combustion...

  4. Propellant Gelation for Green In-Space Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Concerns in recent years about the toxicity and safe handling of the storable class of propellants have led to efforts in greener monopropellants and bi-propellants....

  5. Solid polymer electrolyte water electrolyser based on Nafion-TiO{sub 2} composite membrane for high temperature operation

    Energy Technology Data Exchange (ETDEWEB)

    Baglio, V.; Antonucci, V.; Arico, A.S. [CNR-ITAE, Messina (Italy); Matteucci, F.; Martina, F.; Zama, I. [Tozzi Renewable Energy SpA, Mezzano (Italy); Ciccarella, G. [National Nanotechnology Laboratory (NNL) of INFM-CNR, Distretto Tecnologico ISUFI, Innovazione, Universita del Salento, Lecce (Italy); Arriaga, L.G. [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, Queretaro Sanfandila (Mexico); Ornelas, R.

    2009-06-15

    A composite Nafion-TiO{sub 2} membrane was manufactured by a recast procedure, using an in-house prepared TiO{sub 2}. This membrane has shown promising properties for high temperature operation in an SPE electrolyser allowing to achieve higher performance with respect to a commercial Nafion 115 membrane. This effect is mainly due to the water retention properties of the TiO{sub 2} filler. A promising increase in electrical efficiency was recorded at low current densities for the composite membrane-based SPE electrolyser at high temperature compared to conventional membrane-based devices. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  6. Ionic liquid propellants: future fuels for space propulsion.

    Science.gov (United States)

    Zhang, Qinghua; Shreeve, Jean'ne M

    2013-11-11

    Use of green propellants is a trend for future space propulsion. Hypergolic ionic liquid propellants, which are environmentally-benign while exhibiting energetic performances comparable to hydrazine, have shown great potential to meet the requirements of developing nontoxic high-performance propellant formulations for space propulsion applications. This Concept article presents a review of recent advances in the field of ionic liquid propellants. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Final Report For The Initial Solid Phase Characterization Of The 2011 Grab Samples And Composite For The C-109 Hard Heel Study

    International Nuclear Information System (INIS)

    Page, J.S.; Cooke, G.A.; Pestovich, J.A.

    2011-01-01

    On May 3, 2011, solid phase characterization subsamples were taken from six of the eight grab samples that had been collected from tank 241-C-109 in April, 2011 and delivered to the 222-S Laboratory. These subsamples were characterized in order to guide the creation of the composite for the C-109 hard heel study. Visual observation showed that there was a large variability in the physical characteristics of the eight individual grab samples. Several of the grab samples consisted of 'stone-like' cobbles (several > 25 mm in diameter) while the other grab samples were of a finer granular composition referred to as 'bulk material'. Half of the six subsamples taken for this initial SPC were of crushed cobbles and half were of the bulk material. Scanning electron microscopy was performed on all six subsamples, and X-ray diffraction was performed on all three of the 'bulk material' samples and one of the crushed cobble samples. The crushed cobbles were found to be composed primarily of gibbsite (Al(OHh) 3 ). Analysis by X-ray diffraction indicated gibbsite to be the only crystalline phase detected, and scanning electron microscopy showed the crushed cobbles to consist primarily of aggregates of euhedral to subhedral gibbsite crystals that were 20 to 100 μm in size. The aggregates, having a moderate amount of pore space, were cemented primarily by recrystallized gibbsite making them resistant to crushing. The bulk material consisted of coarse to fine-grained pebble-sized (2 to 20 mm) particles. The X-ray diffraction analysis showed them to be a mixture of natrophosphate (Na 7 (PO 4 ) 2 F·19(H 2 O)) and gibbsite crystals in varying amounts in each of the three subsamples (i.e., some grab samples were primarily natrophosphate while others were mixed with gibbsite). The scanning electron microscopy analysis of the bulk material showed the crystals to be euhedral to anhedral (rounded) in shape. Trace phases, too minor to be detected by XRD, were observed in the SEM analysis

  8. Refinement of Propellant Strand Burning Method to Suit Aluminised Composite Rocket Propellant

    Science.gov (United States)

    2014-12-01

    Garry Hale and Raoul A. Pietrobon Weapons and Combat Systems Division Defence Science and Technology Organisation DSTO-TN-1396... Organisation PO Box 1500 Edinburgh South Australia 5111 Australia Telephone: 1300 362 362 Fax: (08) 7389 6567 © Commonwealth of Australia 2015 AR...with a soft brush (dedusting) and the strands were inhibited with paint diluted by water. The paint was a Super Flat acrylic, deep tint base (Line 500

  9. Hierarchical composites of polyaniline-graphene nanoribbons-carbon nanotubes as electrode materials in all-solid-state supercapacitors

    Science.gov (United States)

    Liu, Mingkai; Miao, Yue-E.; Zhang, Chao; Tjiu, Weng Weei; Yang, Zhibin; Peng, Huisheng; Liu, Tianxi

    2013-07-01

    A three dimensional (3D) polyaniline (PANI)-graphene nanoribbon (GNR)-carbon nanotube (CNT) composite, PANI-GNR-CNT, has been prepared via in situ polymerization of an aniline monomer on the surface of a GNR-CNT hybrid. Here, the 3D GNR-CNT hybrid has been conveniently prepared by partially unzipping the pristine multi-walled CNTs, while the residual CNTs act as ``bridges'' connecting different GNRs. The morphology and structure of the resulting hybrid materials have been characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy and X-ray diffraction (XRD). Electrochemical tests reveal that the hierarchical PANI-GNR-CNT composite based on the two-electrode cell possesses much higher specific capacitance (890 F g-1) than the GNR-CNT hybrid (195 F g-1) and neat PANI (283 F g-1) at a discharge current density of 0.5 A g-1. At the same time, the PANI-GNR-CNT composite displays good cycling stability with a retention ratio of 89% after 1000 cycles, suggesting that this novel PANI-GNR-CNT composite is a promising candidate for energy storage applications.

  10. Structure and mechanical properties of composites of poly(6-hexanelactam) combining solid tribological additives and reinforcing components

    Czech Academy of Sciences Publication Activity Database

    Horský, J.; Kolařík, Jan; Fambri, L.

    2004-01-01

    Roč. 289, č. 4 (2004), s. 5249-5260 ISSN 1438-7492 R&D Projects: GA ČR GA104/01/0004 Institutional research plan: CEZ:AV0Z4050913 Keywords : anionic poly merization * composites * mechanical properties Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.452, year: 2004

  11. Investigation into isomolar series of Al(NO3)3, Na3VO4 solution mixture and composition of solid phases

    International Nuclear Information System (INIS)

    Chernysh, L.F.; Nakhodnova, A.P.; Makarova, R.A.

    1979-01-01

    Conducted is investigation of properties of isomolar series of aluminium nitrate and sodiUm vanadate solutions at pH of the latter 12.5; 10.0; 7.0 and the temperature of 25 deg C using the methods of pH-metry, conductometry, ''seeming'' volume of precipitations, residual concentration of aluminium and vanadium. It is shown, that the composition property diagram of the system investigated does not reflect the true composition of solid-phase products of the reaction, which depends on the component ratio in solution. Bottom phases of isomolar series are mainly heterogeneous. At the excess of sodium vanadate solution and its high pH values conditions for the basic salt formation are created. At pH of the Na 3 VO 4 solution of 12.5 and 10.0 and Al(NO 3 ) 3 : Na 3 VO 4 ratios 4:6 and 3:7 respectively obtained are the basic aluminium vanadates of the (AlOH) 3 (VO 4 ) 2 x 7.5H 2 O and (AlOH) 2 V 2 O 7 x5H 2 O composition, some of their physicochemical properties being investigated

  12. Investigation into isomolar series of Al(NO/sub 3/)/sub 3/, Na/sub 3/VO/sub 4/ solution mixture and composition of solid phases

    Energy Technology Data Exchange (ETDEWEB)

    Chernysh, L F; Nakhodnova, A P; Makarova, R A [Donetskij Gosudarstvennyj Univ. (Ukrainian SSR)

    1979-11-01

    Conducted is investigation of properties of isomolar series of aluminium nitrate and sodium vanadate solutions at pH of the latter 12.5; 10.0; 7.0 and the temperature of 25 deg C using the methods of pH-metry, conductometry, ''seeming'' volume of precipitations, residual concentration of aluminium and vanadium. It is shown, that the composition property diagram of the system investigated does not reflect the true composition of solid-phase products of the reaction, which depends on the component ratio in solution. Bottom phases of isomolar series are mainly heterogeneous. At the excess of sodium vanadate solution and its high pH values conditions for the basic salt formation are created. At pH of the Na/sub 3/VO/sub 4/ solution of 12.5 and 10.0 and Al(NO/sub 3/)/sub 3/: Na/sub 3/VO/sub 4/ ratios 4:6 and 3:7 respectively obtained are the basic aluminium vanadates of the (AlOH)/sub 3/(VO/sub 4/)/sub 2/x 7.5H/sub 2/O and (AlOH)/sub 2/V/sub 2/O/sub 7/x5H/sub 2/O composition, some of their physicochemical properties being investigated.

  13. LaCrO3/CuFe2O4 Composite-Coated Crofer 22 APU Stainless Steel Interconnect of Solid Oxide Fuel Cells

    Science.gov (United States)

    Hosseini, Seyedeh Narjes; Enayati, Mohammad Hossein; Karimzadeh, Fathallah; Dayaghi, Amir Masoud

    2017-07-01

    Rapidly rising contact resistance and cathode Cr poisoning are the major problems associated with unavoidable chromia scale growth on ferritic stainless steel (FSS) interconnects of solid oxide fuel cells. This work investigates the performance of the novel screen-printed composite coatings consisting of dispersed conductive LaCrO3 particles in a CuFe2O4 spinel matrix for Crofer 22 APU FSS, with emphasis on the oxidation behavior and electrical conductivity of these coatings. The results show that the presence of protective spinel coating, accompanied by the effective role of LaCrO3 particle incorporation, prevents the Cr2O3 subscale growth as well as chromium migration into the coating surface at the end of 400 hours of oxidation at 1073 K (800 °C) in air. In addition, the composite coatings decreased the area specific resistance (ASR) from 51.7 and 13.8 mΩ cm2 for uncoated and spinel-coated samples, respectively, to a maximum of 7.7 mΩ cm2 for composite-coated samples after 400 hours of oxidation.

  14. Electrodeposition of a Au-Dy2O3 Composite Solid Oxide Fuel Cell Catalyst from Eutectic Urea/Choline Chloride Ionic Liquid

    Directory of Open Access Journals (Sweden)

    Claudio Mele

    2012-12-01

    Full Text Available  In this research we have fabricated and tested Au/Dy2O3 composites for applications as Solid Oxide Fuel Cell (SOFC electrocatalysts. The material was obtained by a process involving electrodeposition of a Au-Dy alloy from a urea/choline chloride ionic liquid electrolyte, followed by selective oxidation of Dy to Dy2O3 in air at high temperature. The electrochemical kinetics of the electrodeposition bath were studied by cyclic voltammetry, whence optimal electrodeposition conditions were identified. The heat-treated material was characterised from the morphological (scanning electron microscopy, compositional (X-ray fluorescence spectroscopy and structural (X-ray diffractometry points of view. The electrocatalytic activity towards H2 oxidation and O2 reduction was tested at 650 °C by electrochemical impedance spectrometry. Our composite electrodes exhibit an anodic activity that compares favourably with the only literature result available at the time of this writing for Dy2O3 and an even better cathodic performance.

  15. Composite cathode La0.15Bi0.85O1.5-Ag for intermediate-temperature solid oxide fuel cells

    International Nuclear Information System (INIS)

    Gao Zhan; Mao Zongqiang; Huang Jianbing; Gao Ruifeng; Wang Cheng; Liu Zhixiang

    2008-01-01

    Composites consisting of silver and lanthanum stabilized bismuth oxide (La 0.15 Bi 0.85 O 1.5 ) were investigated as cathodes for intermediate-temperature solid oxide fuel cells with doped ceria as electrolyte. No stable phases were formed via reaction between La 0.15 Bi 0.85 O 1.5 and Ag. The microstructure of the interfaces between composite cathodes and Ce 0.8 Sm 0.2 O 1.5 electrolytes was studied by scanning electron microscopy after sintering at various temperatures. Impedance spectroscopy measurements revealed that the performance of cathode fired at 700 deg. C was the best. When the optimum fraction of Ag was 50 vol.%, polarization resistance values for the LSB-Ag50 cathode were as low as 0.14 Ω cm 2 at 700 deg. C and 0.18 Ω cm 2 at 650 deg. C. The steady-state polarization investigations on LSB and LSB-Ag50 cathodes were performed using typical three-electrode test cells in air. The results showed that the LSB-Ag50 composite cathode exhibited a lower overpotential and higher exchange current density than LSB, which indicated the electrochemical performance of LSB-Ag50 for the oxygen reduction reaction was superior to the LSB

  16. Magnetic nanoparticles-nylon 6 composite for the dispersive micro solid phase extraction of selected polycyclic aromatic hydrocarbons from water samples.

    Science.gov (United States)

    Reyes-Gallardo, Emilia M; Lucena, R; Cárdenas, S; Valcárcel, M

    2014-06-06

    In this article, the easy synthesis of magnetic nanoparticles-nylon 6 composite is presented, characterized and applied in the microextraction field. The one-step synthesis of the composite is performed by a solvent changeover playing with the different solubility of the polymeric network in formic acid and water. The new material has been characterized by different techniques including infrared spectroscopy, transmission and scanning microscopy. The extraction performance of the composite under a dispersive micro solid phase extraction format has been evaluated by determining four polycyclic aromatic hydrocarbons (benzo[b]fluoranthene, fluoranthene, indeno[1,2,3-cd]pyrene and phenanthrene) in water using ultra performance liquid chromatography (UPLC) combined with photo diode array detection. The developed methodology allows the determination of the analytes with limits of detection in the range from 0.05 μg/L (benzo[b]fluoranthene) to 0.58 μg/L (phenanthrene). The repeatability of the method was better than 6.9% at the limit of quantification level. The relative recoveries varied in the interval 80-111%. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Bio-composites composed of a solid free-form fabricated polycaprolactone and alginate-releasing bone morphogenic protein and bone formation peptide for bone tissue regeneration.

    Science.gov (United States)

    Kim, MinSung; Jung, Won-Kyo; Kim, GeunHyung

    2013-11-01

    Biomedical scaffolds should be designed with highly porous three-dimensional (3D) structures that have mechanical properties similar to the replaced tissue, biocompatible properties, and biodegradability. Here, we propose a new composite composed of solid free-form fabricated polycaprolactone (PCL), bone morphogenic protein (BMP-2) or bone formation peptide (BFP-1), and alginate for bone tissue regeneration. In this study, PCL was used as a mechanical supporting component to enhance the mechanical properties of the final biocomposite and alginate was used as the deterring material to control the release of BMP-2 and BFP-1. A release test revealed that alginate can act as a good release control material. The in vitro biocompatibilities of the composites were examined using osteoblast-like cells (MG63) and the alkaline phosphatase (ALP) activity and calcium deposition were assessed. The in vitro test results revealed that PCL/BFP-1/Alginate had significantly higher ALP activity and calcium deposition than the PCL/BMP-2/Alginate composite. Based on these findings, release-controlled BFP-1 could be a good growth factor for enhancement of bone tissue growth and the simple-alginate coating method will be a useful tool for fabrication of highly functional biomaterials through release-control supplementation.

  18. Synthesis, microstructure and mechanical properties of (Ti1−x,Nbx)2AlC/Al2O3 solid solution composites

    International Nuclear Information System (INIS)

    Zhu, Jianfeng; Han, Na; Wang, Anning

    2012-01-01

    (Ti,Nb) 2 AlC/Al 2 O 3 in-situ solid solution composites were successfully synthesized from the elemental powder mixtures of Nb 2 O 5 , Ti, Al and carbon black using hot-press-aided reaction synthesis. The reaction path was investigated by differential scanning calorimetry (DSC) and X-ray diffractometry (XRD), and a possible reaction mechanism was proposed to explain the formation of (Ti,Nb) 2 AlC/Al 2 O 3 composites in which the thermite reaction between Al and Nb 2 O 5 formed Al 2 O 3 and Nb, and the latter together with TiAl and TiC reacted to form (Ti,Nb) 2 AlC. The synthesized composites show plate-like grains packed in a laminated structure typical of Ti 2 AlC, and the fine Al 2 O 3 particles formed in-situ tend to disperse on the matrix grain boundaries. Compared with the monolithic Ti 2 AlC synthesized using an identical process, the Vickers hardness, maximum compressive stress, flexural strength and fracture toughness of (Ti 0.96 ,Nb 0.04 ) 2 AlC/5 wt% Al 2 O 3 were enhanced by 33.8%, 12.1%, 118.4% and 111.8%, respectively. The mechanisms by which Al 2 O 3 increases the strength and toughness of the material were also discussed.

  19. Lithiated Nafion as polymer electrolyte for solid-state lithium sulfur batteries using carbon-sulfur composite cathode

    Science.gov (United States)

    Gao, Jing; Sun, Chunshui; Xu, Lei; Chen, Jian; Wang, Chong; Guo, Decai; Chen, Hao

    2018-04-01

    Due to flexible property and light weight, the lithiated Nafion membrane swollen with PC (PC-Li-Nafion) has been employed as both solid-state electrolyte and separator to fabricate solid-state Li-S cells. The electrochemical measurements of PC-Li-Nafion membrane show that its Li-ion transference number is 0.928, ionic conductivity of 2.1 × 10-4 S cm-1 can be achieved at 70 °C and its electrochemical window is 0 ∼ +4.1 V vs. Li+/Li. It is observed that the Li dendrites are suppressed by using PC-Li-Nafion membrane due to its single-ion conducting property. The amounts of Li-Nafion resin binder and conductive carbon in the cathode are optimized as 40% and 10% respectively to make a balance of ionic and electronic conductivities. A thin-layer Li-Nafion resin with a thickness of around 2 μm is fabricated between the cathode and PC-Li-Nafion membrane to improve the interfacial contact and further enhance the specific capacity of the cell. When measured at 70 °C, the Li-S cell delivers a reversible specific capacity of 1072.8 mAh g-1 (S) at 0.05 C and 895 mAh g-1 (S) at 1 C. The capacity retention at 1 C is 89% after 100 cycles. These results suggest that high-performance solid-state Li-S cells can be fabricated with the Li-Nafion polymer electrolyte.

  20. Effect of phospholipid composition and phase on nanodisc films at the solid-liquid interface as studied by neutron reflectivity

    DEFF Research Database (Denmark)

    Wadsäter, Maria Helena; Barker, Robert; Mortensen, Kell

    2013-01-01

    of the cell membrane and can act as a nanometer-sized container for functional single membrane proteins. In this study, we present a general nanodisc-based system, intended for structural and functional studies of membrane proteins. In this method, the nanodiscs are aligned at a solid surface, providing...... the ability to determine the average structure of the film along an axis perpendicular to the interface as measured by neutron reflectivity. The nanodisc film was optimized in terms of nanodisc coverage, reduced film roughness, and stability for time-consuming studies. This was achieved by a systematic...