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Sample records for advanced polymer systems

  1. Advanced Polymer

    NASA Technical Reports Server (NTRS)

    1992-01-01

    In the mid-1980's, Langley developed a polyimide sulfone, combining desirable properties of two classes of polymers. Composites and other products made from polyimide sulfone can be used with solvents and corrosive fluids, are light weight, low cost and can be easily fabricated for a wide range of industrial uses. High Technology Systems, Inc. obtained a license for the polymer and was awarded a Small Business Innovation Research (SBIR) contract for development in a powder form. Although its principal use is as a matrix resin for composites, the material can also be used as a high temperature structural adhesive for aircraft structures and as a coating for protection from heat and radiation for electronic components.

  2. Advanced polymer systems for optoelectronic integrated circuit applications

    NASA Astrophysics Data System (ADS)

    Eldada, Louay A.; Stengel, Kelly M. T.; Shacklette, Lawrence W.; Norwood, Robert A.; Xu, Chengzeng; Wu, Chengjiu; Yardley, James T.

    1997-01-01

    An advanced versatile low-cost polymeric waveguide technology is proposed for optoelectronic integrated circuit applications. We have developed high-performance organic polymeric materials that can be readily made into both multimode and single-mode optical waveguide structures of controlled numerical aperture (NA) and geometry. These materials are formed from highly crosslinked acrylate monomers with specific linkages that determine properties such as flexibility, toughness, loss, and stability against yellowing and humidity. These monomers are intermiscible, providing for precise adjustment of the refractive index from 1.30 to 1.60. Waveguides are formed photolithographically, with the liquid monomer mixture polymerizing upon illumination in the UV via either mask exposure or laser direct-writing. A wide range of rigid and flexible substrates can be used, including glass, quartz, oxidized silicon, glass-filled epoxy printed circuit board substrate, and flexible polyimide film. We discuss the use of these materials on chips and on multi-chip modules (MCMs), specifically in transceivers where we adaptively produced waveguides on vertical-cavity surface-emitting lasers (VCSELs) embedded in transmitter MCMs and on high- speed photodetector chips in receiver MCMs. Light coupling from and to chips is achieved by cutting 45 degree mirrors using excimer laser ablation. The fabrication of our polymeric structures directly on the modules provides for stability, ruggedness, and hermeticity in packaging.

  3. Engineered Polymers for Advanced Drug Delivery

    PubMed Central

    Kim, Sungwon; Kim, Jong-Ho; Jeon, Oju; Kwon, Ick Chan; Park, Kinam

    2009-01-01

    Engineered polymers have been utilized for developing advanced drug delivery systems. The development of such polymers has caused advances in polymer chemistry, which, in turn, has resulted in smart polymers that can respond to changes in environmental condition, such as temperature, pH, and biomolecules. The responses vary widely from swelling/deswelling to degradation. Drug-polymer conjugates and drug-containing nano/micro-particles have been used for drug targeting. Engineered polymers and polymeric systems have also been used in new areas, such as molecular imaging as well as in nanotechnology. This review examines the engineered polymers that have been used as traditional drug delivery and as more recent applications in nanotechnology. PMID:18977434

  4. Advanced polymer PV system: PVMaT 4A1 annual report, September 1995--September 1996

    SciTech Connect

    Hanoka, J; Chleboski, R; Farber, M; Fava, J; Kane, P; Martz, J

    1997-06-01

    Purpose of this subcontract was to produce lower module and systems costs through the innovative use of polymeric materials. The Innovative Mounting System (IMS) was developed and testing begun during the first year of this contract. IMS reduces the cost of installed PV systems by reducing labor and materials costs both in the factory and in field installation. It incorporates several advances in polymers, processing methods and product design. An advanced backskin material permits elimination of the conventional Al perimeter frame by protecting and sealing the edge and by direct bonding of multifunctional mounting bars. Electrical interconnection is easier and more reliable with a new junction box. Feasibility of a non-vacuum, high-throughput lamination method was also demonstrated, involving a novel transparent encapsulant with UV stabilization package that can be laminated in air and which should lead to longer field life than conventional designs. The first-year program culminated in the fielding of prototype products with the new encapsulant, backskin, junction box, frameless edge seal, and IMS. Feedback and marketing information from potential customers were solicited. Result promises a $0.50/watt manufacturing and system cost reductions as well as increased system lifetime. The second year will complete refinement and test of the encapsulant and backskin, complete the new lamination method, and refine product designs.

  5. Polymer lasers: recent advances

    NASA Astrophysics Data System (ADS)

    Riedl, T.; Rabe, T.; Görrn, P.; Wang, J.; Weinmann, T.; Hinze, P.; Galbrecht, F.; Scherf, U.; Kowalsky, W.

    2007-09-01

    The development of organic thin film lasers has seen tremendous progress over the past few years. Only a few materials are necessary to allow for continuous wavelength tunability in the spectral region from the UV to the near IR. At the same time, the lasing thresholds of organic thin film lasers have been reduced considerably both due to improved low-loss distributed feedback (DFB) resonator structures and highly efficient gain materials based on guest-host energy transfer. Aside from the as yet open issue of electrical operation of organic lasers, which we will address briefly in this paper, there are numerous applications (e.g. in biotechnology, spectroscopy) where optically driven organic lasers may be the more cost effective and versatile solution. In this context, tunable polymer lasers pumped by compact and inexpensive InGaN laser diodes will be shown. These lasers are based on a modified poly(9,9'-dioctylfluorene) derivative (BN-PFO) containing 12% of -6,6'-(2,2'-octyloxy-1,1'-binaphthyl) spacer groups doped with a few wt% of the stilbene dye 1,4-Bis(2-(4-(N,N-di(p-tolyl)amino)phenyl)vinyl-benzene (DPAVB). With the same host polymer (BN-PFO) quasi continuous wave operation (up to 5 MHz) can be demonstrated. Highly repetitive lasers are especially desirable for many spectroscopic applications. This regime of operstion is found to be impeded by the photo-physics in doped organic systems where the accumulation of absorptive species in the gain medium leads to piled-up absorption losses and consequently to termination of the lasing process. The presence of the dopand molecules seems to strongly promote the formation and stabilization of the species which we relate to triplet excitons. Therefore, the concentration of the dopand affects the feasibility of quasi-cw operation of thin-film organic lasers. Strategies and results to achieve highly repetitive operation in low-threshold guest-host systems BN-PFO:DPAVB or BN-PFO:poly[2-methoxy-5-(2'-ethylhexyloxy)-1

  6. Polymers for Drug Delivery Systems

    PubMed Central

    Liechty, William B.; Kryscio, David R.; Slaughter, Brandon V.; Peppas, Nicholas A.

    2012-01-01

    Polymers have played an integral role in the advancement of drug delivery technology by providing controlled release of therapeutic agents in constant doses over long periods, cyclic dosage, and tunable release of both hydrophilic and hydrophobic drugs. From early beginnings using off-the-shelf materials, the field has grown tremendously, driven in part by the innovations of chemical engineers. Modern advances in drug delivery are now predicated upon the rational design of polymers tailored for specific cargo and engineered to exert distinct biological functions. In this review, we highlight the fundamental drug delivery systems and their mathematical foundations and discuss the physiological barriers to drug delivery. We review the origins and applications of stimuli-responsive polymer systems and polymer therapeutics such as polymer-protein and polymer-drug conjugates. The latest developments in polymers capable of molecular recognition or directing intracellular delivery are surveyed to illustrate areas of research advancing the frontiers of drug delivery. PMID:22432577

  7. Advanced Polymer Processing Facility

    SciTech Connect

    Muenchausen, Ross E.

    2012-07-25

    Some conclusions of this presentation are: (1) Radiation-assisted nanotechnology applications will continue to grow; (2) The APPF will provide a unique focus for radiolytic processing of nanomaterials in support of DOE-DP, other DOE and advanced manufacturing initiatives; (3) {gamma}, X-ray, e-beam and ion beam processing will increasingly be applied for 'green' manufacturing of nanomaterials and nanocomposites; and (4) Biomedical science and engineering may ultimately be the biggest application area for radiation-assisted nanotechnology development.

  8. Advances in inherently conducting polymers

    SciTech Connect

    Aldissi, M.

    1987-09-01

    The discovery of polyacetylene as the prototype material led to extensive research on its synythesis and characterization. The techniques that emerged as the most important and promising ones are those that dealt with molecular orientation and that resulted in conductivities almost as high as that of copper. The study of dozens of other materials followed. Interest in conducting polymers stems from their nonclassical optical and electronic properties as well as their potential technological applications. However, some of the factors currently limiting their use are the lack of long-term stability and the need to develop conventional low-cost techniques for easy processing. Therefore, research was extended toward solving these problems, and progress has been recently made in that direction. The synthesis of new materials such as stable and easily processable alkylthiophenes, water-soluble polymers, and multicomponent systems, including copolymers and composites, constitutes an important step forward in the area of synthetic metals. However, a full understanding of materials chemistry and properties requires more work in the years to come. Although, few small-scale applications have proven to be successful, long-term stability and applicability tests are needed before their commercial use becomes reality.

  9. Recent advances in photorefractive polymers

    NASA Astrophysics Data System (ADS)

    Thomas, Jayan; Christenson, C. W.; Lynn, B.; Blanche, P.-A.; Voorakaranam, R.; Norwood, R. A.; Yamamoto, M.; Peyghambarian, N.

    2011-10-01

    Photorefractive composites derived from conducting polymers offer the advantage of dynamically recording holograms without the need for processing of any kind. Thus, they are the material of choice for many cutting edge applications, such as updatable three-dimensional (3D) displays and 3D telepresence. Using photorefractive polymers, 3D images or holograms can be seen with the unassisted eye and are very similar to how humans see the actual environment surrounding them. Absence of a large-area and dynamically updatable holographic recording medium has prevented realization of the concept. The development of a novel nonlinear optical chromophore doped photoconductive polymer composite as the recording medium for a refreshable holographic display is discussed. Further improvements in the polymer composites could bring applications in telemedicine, advertising, updatable 3D maps and entertainment.

  10. Redox polymer electrodes for advanced batteries

    DOEpatents

    Gregg, Brian A.; Taylor, A. Michael

    1998-01-01

    Advanced batteries having a long cycle lifetime are provided. More specifically, the present invention relates to electrodes made from redox polymer films and batteries in which either the positive electrode, the negative electrode, or both, comprise redox polymers. Suitable redox polymers for this purpose include pyridyl or polypyridyl complexes of transition metals like iron, ruthenium, osmium, chromium, tungsten and nickel; porphyrins (either free base or metallo derivatives); phthalocyanines (either free base or metallo derivatives); metal complexes of cyclams, such as tetraazacyclotetradecane; metal complexes of crown ethers and metallocenes such as ferrocene, cobaltocene and ruthenocene.

  11. Redox polymer electrodes for advanced batteries

    DOEpatents

    Gregg, B.A.; Taylor, A.M.

    1998-11-24

    Advanced batteries having a long cycle lifetime are provided. More specifically, the present invention relates to electrodes made from redox polymer films and batteries in which either the positive electrode, the negative electrode, or both, comprise redox polymers. Suitable redox polymers for this purpose include pyridyl or polypyridyl complexes of transition metals like iron, ruthenium, osmium, chromium, tungsten and nickel; porphyrins (either free base or metallo derivatives); phthalocyanines (either free base or metallo derivatives); metal complexes of cyclams, such as tetraazacyclotetradecane; metal complexes of crown ethers and metallocenes such as ferrocene, cobaltocene and ruthenocene. 2 figs.

  12. Recent Advances in Simulation of Dendritic Polymers

    SciTech Connect

    Cagin, Tahir; Miklis, Paul J.; Wang, Guofeng; Zamanakos, Georgios; Martin, Ryan; Li, Hao; Mainz, Daniel T.; Nagarajan, V.; Goddard, William A.

    1999-05-11

    Dendrimers and hyperbranched polymers represent a revolution in methodology for directed synthesis of monodisperse polymers with enormous possibility of novel architectures. They demonstrate the ability to attain micelle-like structures with distinct internal and external character. Furthermore, the polyfunctional character of dendrimers allows varied response to environment and promise as selective sensors, carrier for drugs, encapsulation of toxic chemicals and metals. One of the key problems is the characterization of the structures. Theory and simulation can be essential to provide and predict structure and properties. We present some recent advances in theory, modeling and simulation of dendritic polymers.

  13. Polymer-brush lubrication: a review of recent theoretical advances.

    PubMed

    Kreer, T

    2016-04-13

    This review compiles recent theoretical advances to describe compressive and shear forces of polymer-brush bilayers, which consist of two opposing brushes in contact. Such model systems for polymer-brush lubrication are frequently used as a benchmark to gain insight into biological problems, e.g., synovial joint lubrication. Based on scaling theory, I derive conformational and collective properties of polymer-brush bilayers in equilibrium and out-of-equilibrium situations, such as shear forces in the linear and nonlinear response regimes of stationary shear and under non-stationary shear. Furthermore, I discuss the influence of macromolecular inclusions and electrostatic interactions on polymer-brush lubrication. Comparisons to alternative analytical approaches, experiments and numerical results are performed. Special emphasis is given to methods for simulating polymer-brush bilayers using molecular dynamics simulations. PMID:27029521

  14. Polymers as advanced materials for desiccant applications

    SciTech Connect

    Czanderna, A.W.

    1990-12-01

    This research is concerned with solid materials used as desiccants for desiccant cooling systems (DCSs) that process water vapor in an atmosphere to produce cooling. Background information includes an introduction to DCSs and the role of the desiccant as a system component. The water vapor sorption performance criteria used for screening the modified polymers prepared include the water sorption capacity from 5% to 80% relative humidity (R.H.), isotherm shape, and rate of adsorption and desorption. Measurements are presented for the sorption performance of modified polymeric advanced desiccant materials with the quartz crystal microbalance. Isotherms of polystyrene sulfonic acid (PSSA) taken over a 5-month period show that the material has a dramatic loss in capacity and that the isotherm shape is time dependent. The adsorption and desorption kinetics for PSSA and all the ionic salts of it studied are easily fast enough for commercial DCS applications with a wheel rotation speed of 6 min per revolution. Future activities for the project are addressed, and a 5-year summary of the project is included as Appendix A. 34 refs., 20 figs., 3 tabs.

  15. Advanced Polymers Containing the Phenyltrifluoroethylidene Connecting Group

    NASA Technical Reports Server (NTRS)

    Alstron, William B.; Sivko, Gloria S.

    2006-01-01

    A new, lower cost fluorinated dianhydride based on the phenyltrifluoroethylidene (3F) connecting linkage was invented by the principal author in the early 1980's. New 3F condensation and addition cured polyimides were synthesized with the newly discovered 3F dianhydride and the previously known 3F diamine. As controls, polyimides based on the somewhat analogous higher cost hexafluoroisopropylidene (6F) linkage were also prepared. The short term thermal oxidative stability (TOS), determined by thermal gravimetric analysis (TGA), and the glass transition temperatures (Tg) of 3F dianhydride polyimides were found to be similar to 6F dianhydride polyimides, but the Tg was slightly higher for 3F diamine polyimides than 6F diamine polyimides. Unfortunately, in real time testing, long term TOS of 3F polymers was clearly inferior to 6F polymers. This was due to a 3 to 5 fold greater rate of loss of trifluoromethyl group from 3F versus 6F linkages. However, at shorter times or lower temperatures, 3F TOS was almost comparable to 6F TOS. The wide scope of the 3F technology was also demonstrated to have distinct unique advantages over 6F technology through the use of the 3F pendant phenyl ring as a synthetic site to introduce other functional groups. These groups have been used for the control or modification of polymer properties; an advantage lacking within 6F technology. The synthetic ease by which 3F can be introduced into various types of monomers has lead to the explosion of advanced 3F polyimides and other high performance advanced 3F polymers in the prior decade of 3F polymer literature as cited herein; covering polyimides, substituted polyimides, at least ten types of nonpolyimide 3F polymer modifications, and also the government's nine 3F U.S. patents and corporations' nine 3F U.S. patents.

  16. RAFT technology for the production of advanced photoresist polymers

    NASA Astrophysics Data System (ADS)

    Sheehan, Michael T.; Farnham, William B.; Okazaki, Hiroshi; Sounik, James R.; Clark, George

    2008-03-01

    Reversible Addition Fragmentation Chain Transfer (RAFT) technology has been developed for use in producing high yield low polydispersity (PD) polymers for many applications. RAFT technology is being used to produce low PD polymers and to allow control of the polymer architecture. A variety of polymers are being synthesized for use in advanced photoresists using this technique. By varying the RAFT reagent used we can modulate the system reactivity of the RAFT reagent and optimize it for use in acrylate or methacrylate monomer systems (193 and 193i photoresist polymers) or for use in styrenic monomer systems (248 nm photoresist polymers) to achieve PD as low as 1.05. RAFT polymerization technology also allows us to produce block copolymers using a wide variety of monomers. These block copolymers have been shown to be useful in self assembly polymer applications to produce unique and very small feature sizes. The mutual compatibilities of all the components within a single layer 193 photoresist are very important in order to achieve low LWR and low defect count. The advent of immersion imaging demands an additional element of protection at the solid/liquid interface. We have used RAFT technology to produce block copolymers comprising a random "resist" block with composition and size based on conventional dry photoresist materials, and a "low surface energy" block for use in 193i lithography. The relative block lengths and compositions may be varied to tune solution behavior, surface energy, contact angles, and solubility in developer. The use of this technique will be explored to produce polymers used in hydrophobic single layer resists as well as additives compatible with the main photoresist polymer.

  17. Advances in the engineering science of immiscible polymer blends: A powder route for delicate polymer precursors and a highly renewable polyamide/terephthalate blend system

    NASA Astrophysics Data System (ADS)

    Giancola, Giorgiana

    Powder processing of thermoplastic polymer composites is an effective way to achieve a high level of component homogenization in raw blends prior to melt processing, thus reducing the thermal and shear stress on the components. Polymer blends can be prepared that would otherwise not be possible due to thermodynamic incompatibility. Evaluation of this concept was conducted by processing PMMA and HDPE micron sized powders which were characterized using DSC and rheology. Optical microscopy and SEM, showed that high-quality, fine domain sized blends can be made by the compression molding process. Silica marker spheres were used to qualitatively assess the level dispersive mixing. EDS chemical analysis was effective in providing image contrast between PMMA and HDPE based on the carbonyl and ester oxygen. EDS image maps, combined with secondary electron images show that compression molding of blended powder precursors produces composites of comparable homogeneity and domain size as extrusion processing. FTIR proved valuable when assessing the intimacy of the constituents at the interface of the immiscible domains. The formation of an in-situ, PMMA nano-network structure resulting from solvent extraction and redeposition using DMF was uniquely found on the surface of these immiscible polymer blends. This work has shown that powder processing of polymers is an effective means to melt processed fragile polymers to high quality blends. Recently, efforts towards the development of sustainable materials have evolved due in part to the increase in price and limited supply of crude oil. Immiscible polymer blending is a paradigm that enables synergistic material performance in certain instances where the composite properties are superior to the sum of the constituents. The addition of PA6,10 to PTT offers an opportunity to increase the bio-based content of PTT while simultaneously maintaining or improving mechanical properties. PA6,10 and PTT are immiscible polymers that can be

  18. Polymer Energy Rechargeable System Battery Being Developed

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle A.

    2003-01-01

    Long description. Illustrations of discotic liquid crystals, rod-coil polymers, lithium-ion conducting channel dilithium phthalocyanine (Li2Pc) from top and side, novel star polyethylene oxide structures, composite polyethylene oxide materials (showing polyethylene oxide + lithium salt, carbon atoms and oxygen atoms), homopolyrotaxanes, and diblock copolymers In fiscal year 2000, NASA established a program to develop the next generation, lithium-based, polymer electrolyte batteries for aerospace applications. The goal of this program, known as Polymer Energy Rechargeable Systems (PERS), is to develop a space-qualified, advanced battery system embodying polymer electrolyte and lithium-based electrode technologies and to establish world-class domestic manufacturing capabilities for advanced batteries with improved performance characteristics that address NASA s future aerospace battery requirements.

  19. Advances in shape-memory polymer actuation

    NASA Astrophysics Data System (ADS)

    Leng, Jinsong; Liu, Yanju; Lan, Xin

    2009-03-01

    Shape memory polymer (SMP) is a promising smart material, which is able to perform a large deformation upon applying an external stimulus, such as heat, light and moisture, etc. In recent years, many investigations have been advanced in thermo-responsive SMP actuation, and several novel actuations have been applied in SMP. In this paper, the mechanism and demonstration of three types of SMP actuations (infrared laser, physical swelling effect and electricity) are presented. These novel actuation approaches may help SMP to fully reach its potential application. Firstly, for the infrared laser-activated SMP, it is concerned about the drive of SMP by infrared light. The infrared laser, transmitted through the optical fiber embedded in the SMP matrix, was chosen to drive the SMP. The working frequency of infrared laser was installed in 3-4μm. Moreover, this paper presents a study on the effects of solution on the glass transition temperature (Tg). It shows that the hydrogen bonding of SMP was aroused by the absorbed solution that significantly reduces transition temperature of polymer. In this way, the shape memory effect (SME) can undergo solution-driven shape recovery. Finally, the actuation of two types of electro-active SMP composites filled with electrically conductive powders (carbon black, nickel powers) have been carried out, and the SMP composite can be driven by applying a relatively low voltage.

  20. Recent Advances in the Improvement of Polymer Electret Films

    NASA Astrophysics Data System (ADS)

    Erhard, Dominik P.; Lovera, Deliani; von Salis-Soglio, Cosima; Giesa, Reiner; Altstädt, Volker; Schmidt, Hans-Werner

    Polymer electret materials are electrically charged dielectric polymers capable of quasi-permanently retaining their electric field. However, environmental influences such as temperature and humidity reduce their charge stability and restrict applications. Therefore it is of great importance to provide a broad pool of polymer electret materials and to enhance further the charge storage behavior. In this context we report on concepts, measures, and solutions to improve the electret performance of commodity and high performance thermoplastic polymers, which was carried out at the University of Bayreuth in recent years. It is demonstrated that the commodity polymer polypropylene can be manufactured into excellent electret films when certain trisamide additives are incorporated in very low concentrations. Polypropylene can be employed at temperatures up to its continuous service temperature of 70 ∘C. To achieve higher temperature windows we investigated the commodity blend system of poly(phenylene ether) (PPE) and polystyrene (PS). We demonstrate that especially PPE/PS blend films with a composition of 75/25 exhibit remarkably good charge storage retention during the isothermal surface decay (ITPD) tests at 120 ∘C. In addition, the commercially available high performance thermoplastic polyetherimide (PEI) resin containing special phosphorus(III) additives shows very good electret properties at elevated temperatures. These properties can be further enhanced by physical aging; resulting in a charge retention after 24 h at 120 ∘C as high as 95%. The same beneficial effect of physical aging can be used to advance PPE and PPE/PS blends. Polymer electret materials with such charge storage properties have the potential to be employed in microphones, sensor devices, and electret filters.

  1. Recent Advances in Conjugated Polymer Materials for Disease Diagnosis.

    PubMed

    Lv, Fengting; Qiu, Tian; Liu, Libing; Ying, Jianming; Wang, Shu

    2016-02-10

    The extraordinary optical amplification and light-harvesting properties of conjugated polymers impart sensing systems with higher sensitivity, which meets the primary demands of early cancer diagnosis. Recent advances in the detection of DNA methylation and mutation with polyfluorene derivatives based fluorescence resonance energy transfer (FRET) as a means to modulate fluorescent responses attest to the great promise of conjugated polymers as powerful tools for the clinical diagnosis of diseases. To facilitate the ever-changing needs of diagnosis, the development of detection approaches and FRET signal analysis are highlighted in this review. Due to their exceptional brightness, excellent photostability, and low or absent toxicity, conjugated polymers are verified as superior materials for in-vivo imaging, and provide feasibility for future clinical molecular-imaging applications. The integration of conjugated polymers with clinical research has shown profound effects on diagnosis for the early detection of disease-related biomarkers, as well as in-vivo imaging, which leads to a multidisciplinary scientific field with perspectives in both basic research and application issues. PMID:26679834

  2. Design and development of advanced adaptive polymer lenses

    NASA Astrophysics Data System (ADS)

    Santiago, Freddie

    The dissertation presented here describes advancements made in adaptive polymer lens design and implementation. Singlets and doublets lenses were constructed for visible, short- wavelength infrared (SWIR), and middle-wavelength infrared (MWIR) applications. The lenses are implemented in a variety of tactical imaging systems to demonstrate their performance. A process was developed that defines the allowable fabrication variables, first for APL singlets and then for APL doublets. A first-order finite element model is described that enables going from an optical design to APL fabrication. This model was then extended to the design of fluidic doublets, which are equivalent to their two-element glass counter-parts. Two constant volume fluidic chambers were enclosed by three flexible membranes resulting in a variable focal length doublet. Chromatic focal shift was then used to compare numerical modeling to experimentally measured results. These same tools, methodology, and process were lastly used in the definition and fabrication of the SWIR and MWIR adaptive polymer lens for tactical systems. Imaging and illumination systems are presented, based on these lensesnotably an adaptive zoom imaging system, in the MWIR. This is the first known instance of such a system in this band.

  3. Advanced polymer chemistry of organometallic anions

    SciTech Connect

    Chamberlin, R.M.; Abney, K.D.; Balaich, G.J.; Fino, S.A.

    1997-11-01

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of the project was to prepare and characterize new polymers incorporating cobalt dicarbollide. Specific goals were to prepare polymerizable cobalt dicarbollide monomers using the nucleophilic substitution route discovered in laboratories and to establish the reaction conditions required to form polymers from these complexes. This one-year project resulted in two publications (in press), and provided the foundation for further investigations into polymer synthesis and characterization using cobalt dicarbollide and other metallocarboranes. Interest in synthesizing organometallic polymers containing the cobalt bis(dicarbollide) anion is motivated by their possible application as cation exchange materials for the remediation of cesium-137 and strontium-90 from nuclear wastes.

  4. Advanced materials based on polymer blends/polymer blend nanocomposites

    NASA Astrophysics Data System (ADS)

    Shikaleska, A. V.; Pavlovska, F. P.

    2012-09-01

    Processability, morphology, mechanical properties and rheological behavior of poly(vinylchloride) (PVC)/poly(ethylmethacrylate) (PEMA) blends and PVC/PEMA/montmorillonite (MMT) composites, prepared by melt processing in a brabender mixer, were studied. Samples were characterized using SEM, mechanical testing, DMTA and a parallel plate rheometer. Plastograms show that there is noticeable drop of fusion times and increase in melt viscosity torque of both, polymer blend and polymer blend nanocomposite, in comparison with those of neat PVC. SEM images show that homogenous dispersions are obtained. Tensile tests indicate that PVC/PEMA and PVC/PEMA/MMT samples have greater tensile strength and elastic modulus and lower elongation compared to PVC. When solid viscoelastic properties are considered (DMTA), slightly higher storage moduli are obtained whereas more prominent increase of storage modulus is observed when nanoclay particles are added in a PVC/PEMA matrix. From the calculated area of tandelta peak of all tested samples, nanocomposites exhibit the lowest damping behavior. Oscillatory measurements in a molten state were used for determining the frequency dependencies of storage G' and loss G" moduli. It was found that G" curves of neat PVC lie above those of G' suggesting that PVC behaves like viscoelastic liquid. Similar results, but with significantly higher values of G' and G" over the whole frequency range for PVC/PEMA blends were obtained. Steady shear measurements show that the presence of PEMA and nanoclay particles increases the shear stress and shear viscosity of neat PVC. In order to define the rheological equations of state the three material functions were determined. According to these functions all samples exhibit shear thinning behavior and the curves obey the power law equation. As rheological behaviour was found to be strongly dependent on blend's micro and macro structure and it is one of the main factors defining the end properties, attempt was

  5. Recent advances in conjugated polymers for light emitting devices.

    PubMed

    Alsalhi, Mohamad Saleh; Alam, Javed; Dass, Lawrence Arockiasamy; Raja, Mohan

    2011-01-01

    A recent advance in the field of light emitting polymers has been the discovery of electroluminescent conjugated polymers, that is, kind of fluorescent polymers that emit light when excited by the flow of an electric current. These new generation fluorescent materials may now challenge the domination by inorganic semiconductor materials of the commercial market in light-emitting devices such as light-emitting diodes (LED) and polymer laser devices. This review provides information on unique properties of conjugated polymers and how they have been optimized to generate these properties. The review is organized in three sections focusing on the major advances in light emitting materials, recent literature survey and understanding the desirable properties as well as modern solid state lighting and displays. Recently, developed conjugated polymers are also functioning as roll-up displays for computers and mobile phones, flexible solar panels for power portable equipment as well as organic light emitting diodes in displays, in which television screens, luminous traffic, information signs, and light-emitting wallpaper in homes are also expected to broaden the use of conjugated polymers as light emitting polymers. The purpose of this review paper is to examine conjugated polymers in light emitting diodes (LEDs) in addition to organic solid state laser. Furthermore, since conjugated polymers have been approved as light-emitting organic materials similar to inorganic semiconductors, it is clear to motivate these organic light-emitting devices (OLEDs) and organic lasers for modern lighting in terms of energy saving ability. In addition, future aspects of conjugated polymers in LEDs were also highlighted in this review. PMID:21673938

  6. Recent Advances in Conjugated Polymers for Light Emitting Devices

    PubMed Central

    AlSalhi, Mohamad Saleh; Alam, Javed; Dass, Lawrence Arockiasamy; Raja, Mohan

    2011-01-01

    A recent advance in the field of light emitting polymers has been the discovery of electroluminescent conjugated polymers, that is, kind of fluorescent polymers that emit light when excited by the flow of an electric current. These new generation fluorescent materials may now challenge the domination by inorganic semiconductor materials of the commercial market in light-emitting devices such as light-emitting diodes (LED) and polymer laser devices. This review provides information on unique properties of conjugated polymers and how they have been optimized to generate these properties. The review is organized in three sections focusing on the major advances in light emitting materials, recent literature survey and understanding the desirable properties as well as modern solid state lighting and displays. Recently, developed conjugated polymers are also functioning as roll-up displays for computers and mobile phones, flexible solar panels for power portable equipment as well as organic light emitting diodes in displays, in which television screens, luminous traffic, information signs, and light-emitting wallpaper in homes are also expected to broaden the use of conjugated polymers as light emitting polymers. The purpose of this review paper is to examine conjugated polymers in light emitting diodes (LEDs) in addition to organic solid state laser. Furthermore, since conjugated polymers have been approved as light-emitting organic materials similar to inorganic semiconductors, it is clear to motivate these organic light-emitting devices (OLEDs) and organic lasers for modern lighting in terms of energy saving ability. In addition, future aspects of conjugated polymers in LEDs were also highlighted in this review. PMID:21673938

  7. Advanced Polymer For Multilayer Insulating Blankets

    NASA Technical Reports Server (NTRS)

    Haghighat, R. Ross; Shepp, Allan

    1996-01-01

    Polymer resisting degradation by monatomic oxygen undergoing commercial development under trade name "Aorimide" ("atomic-oxygen-resistant imidazole"). Intended for use in thermal blankets for spacecraft in low orbit, useful on Earth in outdoor applications in which sunlight and ozone degrades other plastics. Also used, for example, to make threads and to make films coated with metals for reflectivity.

  8. Advancing polymers of intrinsic microporosity by mechanochemistry

    DOE PAGESBeta

    Zhang, Pengfei; Jiang, Xueguang; Wan, Shun; Dai, Sheng

    2015-02-20

    Herein, we report a fast (15 min) and solvent-free mechanochemical approach to construct polymers of intrinsic microporosity (PIMs) with high molecular mass and low polydispersity by solid grinding. The enhanced reaction efficiency results from the instantaneous frictional heating and continuous exposure of active sites within those solid reactants.

  9. Advanced Developments in Cyclic Polymers: Synthesis, Applications, and Perspectives

    PubMed Central

    Zhu, Yinghuai; Hosmane, Narayan S

    2015-01-01

    Due to the topological effect, cyclic polymers demonstrate different and unique physical and biological properties in comparison with linear counterparts having the same molecular-weight range. With advanced synthetic and analytic technologies, cyclic polymers with different topologies, e.g. multicyclic polymers, have been reported and well characterized. For example, various cyclic DNA and related structures, such as cyclic duplexes, have been prepared conveniently by click chemistry. These types of DNA have increased resistance to enzymatic degradation and have high thermodynamic stability, and thus, have potential therapeutic applications. In addition, cyclic polymers have also been used to prepare organic–inorganic hybrids for applications in catalysis, e.g. catalyst supports. Due to developments in synthetic technology, highly pure cyclic polymers could now be produced in large scale. Therefore, we anticipate discovering more applications in the near future. Despite their promise, cyclic polymers are still less explored than linear polymers like polyolefins and polycarbonates, which are widely used in daily life. Some critical issues, including controlling the molecular weight and finding suitable applications, remain big challenges in the cyclic-polymer field. This review briefly summarizes the commonly used synthetic methodologies and focuses more on the attractive functional materials and their biological properties and potential applications. PMID:26478835

  10. Advanced Vehicle system concepts. [nonpetroleum passenger transportation

    NASA Technical Reports Server (NTRS)

    Hardy, K. S.; Langendoen, J. M.

    1983-01-01

    Various nonpetroleum vehicle system concepts for passenger vehicles in the 1990's are being considered as part of the Advanced Vehicle (AV) Assessment at the Jet Propulsion Laboratory. The vehicle system and subsystem performance requirements, the projected characteristics of mature subsystem candidates, and promising systems are presented. The system candidates include electric and hybrid vehicles powered by electricity with or without a nonpetroleum power source. The subsystem candidates include batteries (aqueous-mobile, flow, high-temperature, and metal-air), fuel cells (phosphoric acid, advanced acids, and solid polymer electrolyte), nonpetroleum heat engines, advanced dc and ac propulsion components, power-peaking devices, and transmissions.

  11. Advanced launch system

    NASA Technical Reports Server (NTRS)

    Monk, Jan C.

    1991-01-01

    The Advanced Launch System (ALS) is presented. The costs, reliability, capabilities, infrastructure are briefly described. Quality approach, failure modes, structural design, technology benefits, and key facilities are outlined. This presentation is represented by viewgraphs.

  12. Advances in Polymer and Polymeric Nanostructures for Protein Conjugation

    PubMed Central

    González-Toro, Daniella C.; Thayumanavan, S.

    2013-01-01

    Linear polymers have been considered the best molecular structures for the formation of efficient protein conjugates due to their biological advantages, synthetic convenience and ease of functionalization. In recent years, much attention has been dedicated to develop synthetic strategies that produce the most control over protein conjugation utilizing linear polymers as scaffolds. As a result, different conjugate models, such as semitelechelic, homotelechelic, heterotelechelic and branched or star polymer conjugates, have been obtained that take advantage of these well-controlled synthetic strategies. Development of protein conjugates using nanostructures and the formation of said nanostructures from protein-polymer bioconjugates are other areas in the protein bioconjugation field. Although several polymer-protein technologies have been developed from these discoveries, few review articles have focused on the design and function of these polymers and nanostructures. This review will highlight some recent advances in protein-linear polymer technologies that employ protein covalent conjugation and successful protein-nanostructure bioconjugates (covalent conjugation as well) that have shown great potential for biological applications. PMID:24058205

  13. Development of advanced polymer nanocomposite capacitors

    NASA Astrophysics Data System (ADS)

    Mendoza, Miguel

    The current development of modern electronics has driven the need for new series of energy storage devices with higher energy density and faster charge/discharge rate. Batteries and capacitors are two of the most widely used energy storage devices. Compared with batteries, capacitors have higher power density and significant higher charge/discharge rate. Therefore, high energy density capacitors play a significant role in modern electronic devices, power applications, space flight technologies, hybrid electric vehicles, portable defibrillators, and pulse power applications. Dielectric film capacitors represent an exceptional alternative for developing high energy density capacitors due to their high dielectric constants, outstanding breakdown voltages, and flexibility. The implementation of high aspect ratio dielectric inclusions such as nanowires into polymer capacitors could lead to further enhancement of its energy density. Therefore, this research effort is focused on the development of a new series of dielectric capacitors composed of nanowire reinforced polymer matrix composites. This concept of nanocomposite capacitors combines the extraordinary physical and chemical properties of the one-dimension (1D) nanoceramics and high dielectric strength of polymer matrices, leading to a capacitor with improved dielectric properties and energy density. Lead-free sodium niobate (NaNbO3) and lead-containing lead magnesium niobate-lead titanate (0.65PMN-0.35PT) nanowires were synthesized following hydrothermal and sol-gel approaches, respectively. The as-prepared nanowires were mixed with a polyvinylidene fluoride (PVDF) matrix using solution-casting method for nanocomposites fabrication. The dielectric constants and breakdown voltages of the NaNbO3/PVDF and 0.65PMN-0.35PT/PVDF nanocomposites were measured under different frequency ranges and temperatures in order to determine their maximum energy (J/cm3) and specific (J/g) densities. The electrical properties of the

  14. Advanced composite polymer electrolyte fuel cell membranes

    SciTech Connect

    Wilson, M.S.; Zawodzinski, T.A.; Gottesfeld, S.; Kolde, J.A.; Bahar, B.

    1995-09-01

    A new type of reinforced composite perfluorinated polymer electrolyte membrane, GORE-SELECT{trademark} (W.L. Gore & Assoc.), is characterized and tested for fuel cell applications. Very thin membranes (5-20 {mu}m thick) are available. The combination of reinforcement and thinness provides high membrane, conductances (80 S/cm{sup 2} for a 12 {mu}m thick membrane at 25{degrees}C) and improved water distribution in the operating fuel cell without sacrificing longevity or durability. In contrast to nonreinforced perfluorinated membranes, the x-y dimensions of the GORE-SELECT membranes are relatively unaffected by the hydration state. This feature may be important from the viewpoints of membrane/electrode interface stability and fuel cell manufacturability.

  15. Advanced drilling systems study

    SciTech Connect

    Pierce, K.G.; Livesay, B.J.

    1995-03-01

    This work was initiated as part of the National Advanced Drilling and Excavation Technologies (NADET) Program. It is being performed through joint finding from the Department of Energy Geothermal Division and the Natural Gas Technology Branch, Morgantown Energy Technology Center. Interest in advanced drilling systems is high. The Geothermal Division of the Department of Energy has initiated a multi-year effort in the development of advanced drilling systems; the National Research Council completed a study of drilling and excavation technologies last year; and the MIT Energy Laboratory recently submitted a proposal for a national initiative in advanced drilling and excavation research. The primary reasons for this interest are financial. Worldwide expenditures on oil and gas drilling approach $75 billion per year. Also, drilling and well completion account for 25% to 50% of the cost of producing electricity from geothermal energy. There is incentive to search for methods to reduce the cost of drilling. Work on ideas to improve or replace rotary drilling technology dates back at least to the 1930`s. There was a significant amount of work in this area in the 1960`s and 1970`s; and there has been some continued effort through the 1980`s. Undoubtedly there are concepts for advanced drilling systems that have yet to be studied; however, it is almost certain that new efforts to initiate work on advanced drilling systems will build on an idea or a variation of an idea that has already been investigated. Therefore, a review of previous efforts coupled with a characterization of viable advanced drilling systems and the current state of technology as it applies to those systems provide the basis for the current study of advanced drilling.

  16. Polymers as advanced materials for desiccant applications, 1988

    SciTech Connect

    Czanderna, A.W.; Neidlinger, H.H.

    1990-09-01

    This report documents work to identify a next-generation, low-cost material with which solar energy or heat from another low-cost energy source can be used for regenerating the water vapor sorption activity of the desiccant. The objective of the work is to determine how the desired sorption performance of advanced desiccant materials can be predicted by understanding the role of the material modifications and material surfaces. The work concentrates on solid materials to be used for desiccant cooling systems and which process water vapor in an atmosphere to produce cooling. The work involved preparing modifications of polystyrene sulfonic acid sodium salt, synthesizing a hydrogel, and evaluating the sorption performances of these and similar commercially available polymeric materials; all materials were studied for their potential application in solid commercial desiccant cooling systems. Background information is also provided on desiccant cooling systems and the role of a desiccant material within such a system, and it includes the use of polymers as desiccant materials. 31 refs., 16 figs., 5 tabs.

  17. Advanced Worker Protection System

    SciTech Connect

    1996-04-01

    The Advanced Worker Protection System (AWPS) is a liquid-air-based, self-contained breathing and cooling system with a duration of 2 hrs. AWPS employs a patented system developed by Oceaneering Space Systems (OSS), and was demonstrated at their facility in Houston, TX as well as at Kansas State University, Manhattan. The heart of the system is the life-support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack is combined with advanced protective garments, an advanced liquid cooling garment (LCG), a respirator, and communications and support equipment. The prototype unit development and testing under Phase 1 has demonstrated that AWPS has the ability to meet performance criteria. These criteria were developed with an understanding of both the AWPS capabilities and the DOE decontamination and decommissioning (D and D) activities protection needs.

  18. IUPAC International Symposium on Polymers for Advanced Technologies, Jerusalem, Israel, Aug. 16-21, 1987, Proceedings

    SciTech Connect

    Lewin, M.

    1988-01-01

    The present conference discusses topics in radiation-sensitive, radiation-modified, and cured polymers, polymers of photoconductive, electroconductive, and piezoelectric type, polymers for advanced structures, liquid-crystal polymers, high-performance polymers compounded from flexible macromolecules, polymer networks, polymer blends, and the matching of composites with adhesives. Attention is given to the industrial radiation-curing of polymers, a frequency-analysis of ferroelectricity, liquid crystal polyester fibers, photochromic and thermochromic liquid crystals, diacetylene-based single-crystal fibers, interpenetrating polymer networks, chain-length development in complex epoxy-amine matrices, and a statistical-thermodynamic theory of polymer precipitation fractionation.

  19. Advanced Monitoring systems initiative

    SciTech Connect

    R.J. Venedam; E.O. Hohman; C.F. Lohrstorfer; S.J. Weeks; J.B. Jones; W.J. Haas

    2004-09-30

    The Advanced Monitoring Systems Initiative (AMSI) actively searches for promising technologies and aggressively moves them from the research bench into DOE/NNSA end-user applications. There is a large unfulfilled need for an active element that reaches out to identify and recruit emerging sensor technologies into the test and evaluation function. Sensor research is ubiquitous, with the seeds of many novel concepts originating in the university systems, but at present these novel concepts do not move quickly and efficiently into real test environments. AMSI is a widely recognized, self-sustaining ''business'' accelerating the selection, development, testing, evaluation, and deployment of advanced monitoring systems and components.

  20. Advanced turbine systems program

    SciTech Connect

    Wilkes, C.; Mukavetz, D.W.; Knickerbocker, T.K.; Ali, S.A.

    1992-01-01

    In accordance with the goals of the DOE program, improvements in the gas turbine are the primary focus of Allison activity during Phase I. To this end Allison conducted a survey of potentially applicable gas turbine cycles and selected the advanced combined cycle as reference system. Extensive analysis of two versions of the advanced combined cycle was performed against the requirement for a 60% thermal efficiency (LHV) utility-sized, natural gas fired system. This analysis resulted in technology requirements for this system. Additional analysis determined emissions potential for the system, established a coal-fueled derivative system and a commercialization plan. This report deals with the technical requirements for a system that meets the thermal efficiency goal. Allison initially investigated four basic thermodynamic cycles: Humid air turbine, intercalate-recuperated systems, advanced combined cycle, chemically recuperated cycle. Our survey and cycle analysis indicated that au had the potential of reaching 60% thermal efficiency. We also concluded that engine hot section technology would be a critical technology regardless of which cycle was chosen. Based on this result Allison chose to concentrate on the advanced combined cycle. This cycle is well known and understood by the utility turbine user community and is therefore likely to be acceptable to users.

  1. Advanced turbine systems program

    SciTech Connect

    Wilkes, C.; Mukavetz, D.W.; Knickerbocker, T.K.; Ali, S.A.

    1992-12-31

    In accordance with the goals of the DOE program, improvements in the gas turbine are the primary focus of Allison activity during Phase I. To this end Allison conducted a survey of potentially applicable gas turbine cycles and selected the advanced combined cycle as reference system. Extensive analysis of two versions of the advanced combined cycle was performed against the requirement for a 60% thermal efficiency (LHV) utility-sized, natural gas fired system. This analysis resulted in technology requirements for this system. Additional analysis determined emissions potential for the system, established a coal-fueled derivative system and a commercialization plan. This report deals with the technical requirements for a system that meets the thermal efficiency goal. Allison initially investigated four basic thermodynamic cycles: Humid air turbine, intercalate-recuperated systems, advanced combined cycle, chemically recuperated cycle. Our survey and cycle analysis indicated that au had the potential of reaching 60% thermal efficiency. We also concluded that engine hot section technology would be a critical technology regardless of which cycle was chosen. Based on this result Allison chose to concentrate on the advanced combined cycle. This cycle is well known and understood by the utility turbine user community and is therefore likely to be acceptable to users.

  2. System Applies Polymer Powder To Filament Tow

    NASA Technical Reports Server (NTRS)

    Baucom, Robert M.; Snoha, John J.; Marchello, Joseph M.

    1993-01-01

    Polymer powder applied uniformly and in continuous manner. Powder-coating system applies dry polymer powder to continuous fiber tow. Unique filament-spreading technique, combined with precise control of tension on fibers in system, ensures uniform application of polymer powder to web of spread filaments. Fiber tows impregnated with dry polymer powders ("towpregs") produced for preform-weaving and composite-material-molding applications. System and process valuable to prepreg industry, for production of flexible filament-windable tows and high-temperature polymer prepregs.

  3. Advanced Solar Power Systems

    NASA Technical Reports Server (NTRS)

    Atkinson, J. H.; Hobgood, J. M.

    1984-01-01

    The Advanced Solar Power System (ASPS) concentrator uses a technically sophisticated design and extensive tooling to produce very efficient (80 to 90%) and versatile energy supply equipment which is inexpensive to manufacture and requires little maintenance. The advanced optical design has two 10th order, generalized aspheric surfaces in a Cassegrainian configuration which gives outstanding performance and is relatively insensitive to temperature changes and wind loading. Manufacturing tolerances also have been achieved. The key to the ASPS is the direct absorption of concentrated sunlight in the working fluid by radiative transfers in a black body cavity. The basic ASPS design concepts, efficiency, optical system, and tracking and focusing controls are described.

  4. Advanced Containment System

    DOEpatents

    Kostelnik, Kevin M.; Kawamura, Hideki; Richardson, John G.; Noda, Masaru

    2005-02-08

    An advanced containment system for containing buried waste and associated leachate. The advanced containment system comprises a plurality of casing sections with each casing section interlocked to an adjacent casing section. Each casing section includes a complementary interlocking structure that interlocks with the complementary interlocking structure on an adjacent casing section. A barrier filler substantially fills the casing sections and may substantially fill the spaces of the complementary interlocking structure to form a substantially impermeable barrier. Some of the casing sections may include sensors so that the casing sections and the zone of interest may be remotely monitored after the casing sections are emplaced in the ground.

  5. Bridging Microstructure, Properties and Processing of Polymer Based Advanced Materials

    SciTech Connect

    Li, Dongsheng; Ahzi, Said; Khaleel, Mohammad A.

    2012-01-01

    This is a guest editorial for a special issue in Journal of Engineering Materials and Technology. The papers collected in this special issue emphasize significant challenges, current approaches and future strategies necessary to advance the development of polymer-based materials. They were partly presented at the symposium of 'Bridging microstructure, properties and processing of polymer based advanced materials' in the TMS 2011 annual conference meeting, which was held in San Diego, US, on Feb 28 to March 3, 2011. This symposium was organized by the Pacific Northwest National Laboratory (USA) and the Institute of Mechanics of Fluids and Solids of the University of Strasbourg (France). The organizers were D.S. Li, S. Ahzi, and M. Khaleel.

  6. Advanced communications satellite systems

    NASA Technical Reports Server (NTRS)

    Sivo, J. N.

    1983-01-01

    There is a rapidly growing demand for satellite circuits, particularly for domestic service within the U.S. NASA's current program is aimed at developing the high risk, advanced satellite communications technologies required to significantly increase the capacity of future satellite communications systems. Attention is given to aspects of traffic distribution and service scenario, problems related to effects of rain attenuation, details regarding system configuration, a 30/20 GHz technology development approach, an experimental flight system, the communications payload for the experimental flight system, a typical experiment flight system coverage, and a typical three axis stabilized flight spacecraft.

  7. Advanced Distribution Management System

    NASA Astrophysics Data System (ADS)

    Avazov, Artur R.; Sobinova, Liubov A.

    2016-02-01

    This article describes the advisability of using advanced distribution management systems in the electricity distribution networks area and considers premises of implementing ADMS within the Smart Grid era. Also, it gives the big picture of ADMS and discusses the ADMS advantages and functionalities.

  8. Advanced Microturbine Systems

    SciTech Connect

    Lindberg, Laura

    2005-04-29

    Dept. of Energy (DOE) Cooperative Agreement DE-FC02-00-CH11061 was originally awarded to Honeywell International, Inc. Honeywell Power Systems Inc. (HPSI) division located in Albuquerque, NM in October 2000 to conduct a program titled Advanced Microturbine Systems (AMS). The DOE Advanced Microturbines Systems Program was originally proposed as a five-year program to design and develop a high efficiency, low emissions, durable microturbine system. The period of performance was to be October 2000 through September 2005. Program efforts were underway, when one year into the program Honeywell sold the intellectual property of Honeywell Power Systems Inc. and HPSI ceased business operations. Honeywell made an internal decision to restructure the existing program due to the HPSI shutdown and submitted a formal request to DOE on September 24, 2001 to transfer the Cooperative Agreement to Honeywell Engines, Systems and Services (HES&S) in Phoenix, AZ in order to continue to offer support for DOE's Advanced Microturbine Program. Work continued on the descoped program under Cooperative Agreement No. DE-FC26-00-CH11061 and has been completed.

  9. Polymers Advance Heat Management Materials for Vehicles

    NASA Technical Reports Server (NTRS)

    2013-01-01

    For 6 years prior to the retirement of the Space Shuttle Program, the shuttles carried an onboard repair kit with a tool for emergency use: two tubes of NOAX, or "good goo," as some people called it. NOAX flew on all 22 flights following the Columbia accident, and was designed to repair damage that occurred on the exterior of the shuttle. Bill McMahon, a structural materials engineer at Marshall Space Flight Center says NASA needed a solution for the widest range of possible damage to the shuttle s exterior thermal protection system. "NASA looked at several options in early 2004 and decided on a sealant. Ultimately, NOAX performed the best and was selected," he says. To prove NOAX would work effectively required hundreds of samples manufactured at Marshall and Johnson, and a concerted effort from various NASA field centers. Johnson Space Center provided programmatic leadership, testing, tools, and crew training; Glenn Research Center provided materials analysis; Langley Research Center provided test support and led an effort to perform large patch repairs; Ames Research Center provided additional testing; and Marshall provided further testing and the site of NOAX manufacturing. Although the sealant never had to be used in an emergency situation, it was tested by astronauts on samples of reinforced carbon-carbon (RCC) during two shuttle missions. (RCC is the thermal material on areas of the shuttle that experience the most heat, such as the nose cone and wing leading edges.) The material handled well on orbit, and tests showed the NOAX patch held up well on RCC.

  10. Advanced imaging system

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This document describes the Advanced Imaging System CCD based camera. The AIS1 camera system was developed at Photometric Ltd. in Tucson, Arizona as part of a Phase 2 SBIR contract No. NAS5-30171 from the NASA/Goddard Space Flight Center in Greenbelt, Maryland. The camera project was undertaken as a part of the Space Telescope Imaging Spectrograph (STIS) project. This document is intended to serve as a complete manual for the use and maintenance of the camera system. All the different parts of the camera hardware and software are discussed and complete schematics and source code listings are provided.

  11. Advanced information processing system

    NASA Technical Reports Server (NTRS)

    Lala, J. H.

    1984-01-01

    Design and performance details of the advanced information processing system (AIPS) for fault and damage tolerant data processing on aircraft and spacecraft are presented. AIPS comprises several computers distributed throughout the vehicle and linked by a damage tolerant data bus. Most I/O functions are available to all the computers, which run in a TDMA mode. Each computer performs separate specific tasks in normal operation and assumes other tasks in degraded modes. Redundant software assures that all fault monitoring, logging and reporting are automated, together with control functions. Redundant duplex links and damage-spread limitation provide the fault tolerance. Details of an advanced design of a laboratory-scale proof-of-concept system are described, including functional operations.

  12. Advanced Life Support Systems

    NASA Technical Reports Server (NTRS)

    Barta, Daniel J.

    2004-01-01

    This presentation is planned to be a 10-15 minute "catalytic" focused presentation to be scheduled during one of the working sessions at the TIM. This presentation will focus on Advanced Life Support technologies key to future human Space Exploration as outlined in the Vision, and will include basic requirements, assessment of the state-of-the-art and gaps, and include specific technology metrics. The presentation will be technical in character, lean heavily on data in published ALS documents (such as the Baseline Values and Assumptions Document) but not provide specific technical details or build to information on any technology mentioned (thus the presentation will be benign from an export control and a new technology perspective). The topics presented will be focused on the following elements of Advanced Life Support: air revitalization, water recovery, waste management, thermal control, habitation systems, food systems and bioregenerative life support.

  13. Interpenetrating Polymer Networks as Innovative Drug Delivery Systems

    PubMed Central

    Lohani, Alka; Singh, Garima; Bhattacharya, Shiv Sankar; Verma, Anurag

    2014-01-01

    Polymers have always been valuable excipients in conventional dosage forms, also have shown excellent performance into the parenteral arena, and are now capable of offering advanced and sophisticated functions such as controlled drug release and drug targeting. Advances in polymer science have led to the development of several novel drug delivery systems. Interpenetrating polymer networks (IPNs) have shown superior performances over the conventional individual polymers and, consequently, the ranges of applications have grown rapidly for such class of materials. The advanced properties of IPNs like swelling capacity, stability, biocompatibility, nontoxicity and biodegradability have attracted considerable attention in pharmaceutical field especially in delivering bioactive molecules to the target site. In the past few years various research reports on the IPN based delivery systems showed that these carriers have emerged as a novel carrier in controlled drug delivery. The present review encompasses IPNs, their types, method of synthesis, factors which affects the morphology of IPNs, extensively studied IPN based drug delivery systems, and some natural polymers widely used for IPNs. PMID:24949205

  14. Advanced Proton Conducting Polymer Electrolytes for Electrochemical Capacitors

    NASA Astrophysics Data System (ADS)

    Gao, Han

    Research on solid electrochemical energy storage devices aims to provide high performance, low cost, and safe operation solutions for emerging applications from flexible consumer electronics to microelectronics. Polymer electrolytes, minimizing device sealing and liquid electrolyte leakage, are key enablers for these next-generation technologies. In this thesis, a novel proton-conducing polymer electrolyte system has been developed using heteropolyacids (HPAs) and polyvinyl alcohol for electrochemical capacitors. A thorough understanding of proton conduction mechanisms of HPAs together with the interactions among HPAs, additives, and polymer framework has been developed. Structure and chemical bonding of the electrolytes have been studied extensively to identify and elucidate key attributes affecting the electrolyte properties. Numerical models describing the proton conduction mechanism have been applied to differentiate those attributes. The performance optimization of the polymer electrolytes through additives, polymer structural modifications, and synthesis of alternative HPAs has achieved several important milestones, including: (a) high proton mobility and proton density; (b) good ion accessibility at electrode/electrolyte interface; (c) wide electrochemical stability window; and (d) good environmental stability. Specifically, high proton mobility has been addressed by cross-linking the polymer framework to improve the water storage capability at normal-to-high humidity conditions (e.g. 50-80% RH) as well as by incorporating nano-fillers to enhance the water retention at normal humidity levels (e.g. 30-60% RH). High proton density has been reached by utilizing additional proton donors (i.e. acidic plasticizers) and by developing different HPAs. Good ion accessibility has been achieved through addition of plasticizers. Electrochemical stability window of the electrolyte system has also been investigated and expanded by utilizing HPAs with different heteroatoms

  15. Recent Trends of Polymer Mediated Liposomal Gene Delivery System

    PubMed Central

    Lee, Sang-Soo; George Priya Doss, C.; Yagihara, Shin; Kim, Do-Young

    2014-01-01

    Advancement in the gene delivery system have resulted in clinical successes in gene therapy for patients with several genetic diseases, such as immunodeficiency diseases, X-linked adrenoleukodystrophy (X-ALD) blindness, thalassemia, and many more. Among various delivery systems, liposomal mediated gene delivery route is offering great promises for gene therapy. This review is an attempt to depict a portrait about the polymer based liposomal gene delivery systems and their future applications. Herein, we have discussed in detail the characteristics of liposome, importance of polymer for liposome formulation, gene delivery, and future direction of liposome based gene delivery as a whole. PMID:25250340

  16. New Polymer Electrolyte Cell Systems

    NASA Technical Reports Server (NTRS)

    Smyrl, William H.; Owens, Boone B.; Mann, Kent; Pappenfus, T.; Henderson, W.

    2004-01-01

    PAPERS PUBLISHED: 1. Pappenfus, Ted M.; Henderson, Wesley A.; Owens, Boone B.; Mann, Kent R.; Smyrl, William H. Complexes of Lithium Imide Salts with Tetraglyme and Their Polyelectrolyte Composite Materials. Journal of the Electrochemical Society (2004), 15 1 (2), A209-A2 15. 2. Pappenfus, Ted M.; Henderson, Wesley A.; Owens, Boone B.; Mann, Kent R.; Smyrl, William H. Ionic-liquidlpolymer electrolyte composite materials for electrochemical device applications. Polymeric Materials Science and Engineering (2003), 88 302. 3. Pappenfus, Ted R.; Henderson, Wesley A.; Owens, Boone B.; Mann, Kent R.; and Smyrl, William H. Ionic Conductivity of a poly(vinylpyridinium)/Silver Iodide Solid Polymer Electrolyte System. Solid State Ionics (in press 2004). 4. Pappenfus Ted M.; Mann, Kent R; Smyrl, William H. Polyelectrolyte Composite Materials with LiPFs and Tetraglyme. Electrochemical and Solid State Letters, (2004), 7(8), A254.

  17. Advanced Clothing System

    NASA Technical Reports Server (NTRS)

    Broyan, James; Orndoff, Evelyne

    2014-01-01

    The goal of the Advanced Clothing System (ACS) is to use advanced commercial off-the-shelf fibers and antimicrobial treatments with the goal of directly reducing the mass and volume of a logistics item. The current clothing state-of-the-art on the International Space Station (ISS) is disposable, mostly cotton-based, clothing with no laundry provisions. Each clothing article has varying use periods and will become trash. The goal is to increase the length of wear of the clothing to reduce the logistical mass and volume. The initial focus has been exercise clothing since the use period is lower. Various ground studies and an ISS technology demonstration have been conducted to evaluate clothing preference and length of wear. The analysis indicates that use of ACS selected garments (e.g. wool, modacrylic, polyester) can increase the breakeven point for laundry to 300 days.

  18. Advanced Clothing System

    NASA Technical Reports Server (NTRS)

    Schlesinger, Thilini; Broyan, James; Orndoff, Evelyne

    2014-01-01

    The goal of the Advanced Clothing System (ACS) is to use advanced commercial off-theshelf fibers and antimicrobial treatments with the goal of directly reducing the mass and volume of a logistics item. The current clothing state-of-the-art on the International Space Station (ISS) is disposable, mostly cotton-based, clothing with no laundry provisions. Each clothing article has varying use periods and will become trash. The goal is to increase the length of wear of the clothing to reduce the logistical mass and volume. The initial focus has been exercise clothing since the use period is lower. Various ground studies and an ISS technology demonstration have been conducted to evaluate clothing preference and length of wear. The analysis indicates that use of ACS selected garments (e.g. wool, modacrylic, polyester) can increase the breakeven point for laundry to 300 days.

  19. Advanced worker protection system

    SciTech Connect

    Caldwell, B.; Duncan, P.; Myers, J.

    1995-12-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project will result in the development of an Advanced Worker Protection System (AWPS). The AWPS will be built around a life support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack will be combined with advanced protective garments, advanced liquid cooling garment, respirator, communications, and support equipment to provide improved worker protection, simplified system maintenance, and dramatically improve worker productivity through longer duration work cycles. Phase I of the project has resulted in a full scale prototype Advanced Worker Protection Ensemble (AWPE, everything the worker will wear), with sub-scale support equipment, suitable for integrated testing and preliminary evaluation. Phase II will culminate in a full scale, certified, pre-production AWPS and a site demonstration.

  20. ADVANCED TURBINE SYSTEMS PROGRAM

    SciTech Connect

    Gregory Gaul

    2004-04-21

    Natural gas combustion turbines are rapidly becoming the primary technology of choice for generating electricity. At least half of the new generating capacity added in the US over the next twenty years will be combustion turbine systems. The Department of Energy has cosponsored with Siemens Westinghouse, a program to maintain the technology lead in gas turbine systems. The very ambitious eight year program was designed to demonstrate a highly efficient and commercially acceptable power plant, with the ability to fire a wide range of fuels. The main goal of the Advanced Turbine Systems (ATS) Program was to develop ultra-high efficiency, environmentally superior and cost effective competitive gas turbine systems for base load application in utility, independent power producer and industrial markets. Performance targets were focused on natural gas as a fuel and included: System efficiency that exceeds 60% (lower heating value basis); Less than 10 ppmv NO{sub x} emissions without the use of post combustion controls; Busbar electricity that are less than 10% of state of the art systems; Reliability-Availability-Maintainability (RAM) equivalent to current systems; Water consumption minimized to levels consistent with cost and efficiency goals; and Commercial systems by the year 2000. In a parallel effort, the program was to focus on adapting the ATS engine to coal-derived or biomass fuels. In Phase 1 of the ATS Program, preliminary investigators on different gas turbine cycles demonstrated that net plant LHV based efficiency greater than 60% was achievable. In Phase 2 the more promising cycles were evaluated in greater detail and the closed-loop steam-cooled combined cycle was selected for development because it offered the best solution with least risk for achieving the ATS Program goals for plant efficiency, emissions, cost of electricity and RAM. Phase 2 also involved conceptual ATS engine and plant design and technology developments in aerodynamics, sealing

  1. Advancements of molecularly imprinted polymers in the food safety field.

    PubMed

    Wang, Peilong; Sun, Xiaohua; Su, Xiaoou; Wang, Tie

    2016-06-01

    Molecularly imprinted technology (MIT) has been widely employed to produce stable, robust and cheap molecularly imprinted polymer (MIP) materials that possess selective binding sites for recognition of target analytes in food, such as pesticides, veterinary drugs, mycotoxins, illegal drugs and so on. Because of high selectivity and specificity, MIPs have drawn great attention in the food safety field. In this review, the recent developments of MIPs in various applications for food safety, including sample preparation, chromatographic separation, sensing, immunoassay etc., have been summarized. We particularly discuss the advancements and limitations in these applications, as well as attempts carried out for their improvement. PMID:26937495

  2. Recent advances in solid polymer electrolyte fuel cell technology

    SciTech Connect

    Ticianelli, E.A.; Srinivasan, S.; Gonzalez, E.R.

    1988-01-01

    With methods used to advance solid polymer electrolyte fuel cell technology, we are close to obtaining the goal of 1 A/cm/sup 2/ at 0.7. Higher power densities have been reported (2 A/cm/sup 2/ at 0.5 V) but only with high catalyst loading electrodes (2 mg/cm/sup 2/ and 4 mg/cm/sup 2/ at anode and cathode, respectively) and using a Dow membrane with a better conductivity and water retention characteristics. Work is in progress to ascertain performances of cells with Dow membrane impregnated electrodes and Dow membrane electrolytes. 5 refs., 6 figs.

  3. Advanced Electrophysiologic Mapping Systems

    PubMed Central

    2006-01-01

    Executive Summary Objective To assess the effectiveness, cost-effectiveness, and demand in Ontario for catheter ablation of complex arrhythmias guided by advanced nonfluoroscopy mapping systems. Particular attention was paid to ablation for atrial fibrillation (AF). Clinical Need Tachycardia Tachycardia refers to a diverse group of arrhythmias characterized by heart rates that are greater than 100 beats per minute. It results from abnormal firing of electrical impulses from heart tissues or abnormal electrical pathways in the heart because of scars. Tachycardia may be asymptomatic, or it may adversely affect quality of life owing to symptoms such as palpitations, headaches, shortness of breath, weakness, dizziness, and syncope. Atrial fibrillation, the most common sustained arrhythmia, affects about 99,000 people in Ontario. It is associated with higher morbidity and mortality because of increased risk of stroke, embolism, and congestive heart failure. In atrial fibrillation, most of the abnormal arrhythmogenic foci are located inside the pulmonary veins, although the atrium may also be responsible for triggering or perpetuating atrial fibrillation. Ventricular tachycardia, often found in patients with ischemic heart disease and a history of myocardial infarction, is often life-threatening; it accounts for about 50% of sudden deaths. Treatment of Tachycardia The first line of treatment for tachycardia is antiarrhythmic drugs; for atrial fibrillation, anticoagulation drugs are also used to prevent stroke. For patients refractory to or unable to tolerate antiarrhythmic drugs, ablation of the arrhythmogenic heart tissues is the only option. Surgical ablation such as the Cox-Maze procedure is more invasive. Catheter ablation, involving the delivery of energy (most commonly radiofrequency) via a percutaneous catheter system guided by X-ray fluoroscopy, has been used in place of surgical ablation for many patients. However, this conventional approach in catheter ablation

  4. Advanced drilling systems study.

    SciTech Connect

    Pierce, Kenneth G.; Livesay, Billy Joe; Finger, John Travis

    1996-05-01

    This report documents the results of a study of advanced drilling concepts conducted jointly for the Natural Gas Technology Branch and the Geothermal Division of the U.S. Department of Energy. A number of alternative rock cutting concepts and drilling systems are examined. The systems cover the range from current technology, through ongoing efforts in drilling research, to highly speculative concepts. Cutting mechanisms that induce stress mechanically, hydraulically, and thermally are included. All functions necessary to drill and case a well are considered. Capital and operating costs are estimated and performance requirements, based on comparisons of the costs for alternative systems to conventional drilling technology, are developed. A number of problems common to several alternatives and to current technology are identified and discussed.

  5. Supramolecular polymer adhesives: advanced materials inspired by nature.

    PubMed

    Heinzmann, Christian; Weder, Christoph; de Espinosa, Lucas Montero

    2016-01-21

    Due to their dynamic, stimuli-responsive nature, non-covalent interactions represent versatile design elements that can be found in nature in many molecular processes or materials, where adaptive behavior or reversible connectivity is required. Examples include molecular recognition processes, which trigger biological responses or cell-adhesion to surfaces, and a broad range of animal secreted adhesives with environment-dependent properties. Such advanced functionalities have inspired researchers to employ similar design approaches for the development of synthetic polymers with stimuli-responsive properties. The utilization of non-covalent interactions for the design of adhesives with advanced functionalities such as stimuli responsiveness, bonding and debonding on demand capability, surface selectivity or recyclability is a rapidly emerging subset of this field, which is summarized in this review. PMID:26203784

  6. Current Advances in Polymer-Based Nanotheranostics for Cancer Treatment and Diagnosis

    PubMed Central

    2015-01-01

    Nanotheranostics is a relatively new, fast-growing field that combines the advantages of treatment and diagnosis via a single nanoscale carrier. The ability to bundle both therapeutic and diagnostic capabilities into one package offers exciting prospects for the development of novel nanomedicine. Nanotheranostics can deliver treatment while simultaneously monitoring therapy response in real-time, thereby decreasing the potential of over- or under-dosing patients. Polymer-based nanomaterials, in particular, have been used extensively as carriers for both therapeutic and bioimaging agents and thus hold great promise for the construction of multifunctional theranostic formulations. Herein, we review recent advances in polymer-based systems for nanotheranostics, with a particular focus on their applications in cancer research. We summarize the use of polymer nanomaterials for drug delivery, gene delivery, and photodynamic therapy, combined with imaging agents for magnetic resonance imaging, radionuclide imaging, and fluorescence imaging. PMID:25014486

  7. Advanced Containment System

    DOEpatents

    Kostelnik, Kevin M.; Kawamura, Hideki; Richardson, John G.; Noda, Masaru

    2005-05-24

    An advanced containment system for containing buried waste and associated leachate. A trench is dug on either side of the zone of interest containing the buried waste so as to accommodate a micro tunnel boring machine. A series of small diameter tunnels are serially excavated underneath the buried waste. The tunnels are excavated by the micro tunnel boring machine at a consistent depth and are substantially parallel to each other. As tunneling progresses, steel casing sections are connected end to end in the excavated portion of the tunnel so that a steel tube is formed. Each casing section has complementary interlocking structure running its length that interlocks with complementary interlocking structure on the adjacent casing section. Thus, once the first tube is emplaced, placement of subsequent tubes is facilitated by the complementary interlocking structure on the adjacent, previously placed, casing sections.

  8. Advanced Containment System

    DOEpatents

    Kostelnik, Kevin M.; Kawamura, Hideki; Richardson, John G.; Noda, Masaru

    2004-10-12

    An advanced containment system for containing buried waste and associated leachate. A trench is dug on either side of the zone of interest containing the buried waste so as to accommodate a micro tunnel boring machine. A series of small diameter tunnels are serially excavated underneath the buried waste. The tunnels are excavated by the micro tunnel boring machine at a consistent depth and are substantially parallel to each other. As tunneling progresses, steel casing sections are connected end to end in the excavated portion of the tunnel so that a steel tube is formed. Each casing section has complementary interlocking structure running its length that interlocks with complementary interlocking structure on the adjacent casing section. Thus, once the first tube is emplaced, placement of subsequent tubes is facilitated by the complementary interlocking structure on the adjacent, previously placed, casing sections.

  9. Advances in Gene Delivery Systems

    PubMed Central

    Kamimura, Kenya; Suda, Takeshi; Zhang, Guisheng; Liu, Dexi

    2011-01-01

    The transfer of genes into cells, both in vitro and in vivo, is critical for studying gene function and conducting gene therapy. Methods that utilize viral and nonviral vectors, as well as physical approaches, have been explored. Viral vector-mediated gene transfer employs replication-deficient viruses such as retro-virus, adenovirus, adeno-associated virus and herpes simplex virus. A major advantage of viral vectors is their high gene delivery efficiency. The nonviral vectors developed so far include cationic liposomes, cationic polymers, synthetic peptides and naturally occurring compounds. These nonviral vectors appear to be highly effective in gene delivery to cultured cells in vitro but are significantly less effective in vivo. Physical methods utilize mechanical pressure, electric shock or hydrodynamic force to transiently permeate the cell membrane to transfer DNA into target cells. They are simpler than viral- and nonviral-based systems and highly effective for localized gene delivery. The past decade has seen significant efforts to establish the most desirable method for safe, effective and target-specific gene delivery, and good progress has been made. The objectives of this review are to (i) explain the rationale for the design of viral, nonviral and physical methods for gene delivery; (ii) provide a summary on recent advances in gene transfer technology; (iii) discuss advantages and disadvantages of each of the most commonly used gene delivery methods; and (iv) provide future perspectives. PMID:22200988

  10. Nonlinear Optics in Novel Polymer Systems.

    NASA Astrophysics Data System (ADS)

    Li, Lian

    Polymeric nonlinear optical (NLO) materials have recently attracted considerable attention and been the subject of intensive investigations. Polymeric NLO materials possessing large second and third order NLO properties, ultrafast response times, high optical damage threshold, transparency over a broad wavelength range, and capability to be easily processed into good optical quality thin films, offer significant advantages over the traditional inorganic materials for applications in fabricating integrated optical devices, such as waveguide electro-optic (EO) modulators and optical frequency doublers, and optical signal processing devices. This dissertation presents the experimental investigations on novel NLO polymers synthesized in the Laboratory of Electronic and Photonic Materials at University of Massachusetts Lowell. Progress made for the past few years on polymeric NLO materials is reviewed, especially with regard to the second order NLO properties of the polymeric materials. Two novel stable second order NLO polymer systems, an interpenetrating polymer network (IPN) formed via thermal crosslinking and a sol-gel process, and a photocrosslinkable conducting polymer, upon poling and crosslinking, exhibited large and stable second order NLO properties measured for these polymers by using the second harmonic generation (SHG) technique. For the IPN system, the SHG measurements as a function of time at several elevated temperatures indicate the superb stability of the second order NLO properties. For the conducting NLO polymer, the NLO property of the poled and photocrosslinked polymer film is stable at room temperature. The wavelength shifting of a Q-switched Nd:YAG laser by stimulated Raman scattering is also described. Measurements were made on the third order NLO properties of a dye doped photocrosslinkable guest-host polymer system at different dye concentrations with a modified Michelson interferometer. By functionalizing the dye to make it more compatible to

  11. Micromechanical characterization of nonlinear behavior of advanced polymer matrix composites

    NASA Technical Reports Server (NTRS)

    Gates, Thomas S.; Chen, J. L.; Sun, C. T.

    1994-01-01

    Due to the presence of curing stresses and oriented crystalline structures in the matrix of polymer matrix fiber composites, the in situ nonlinear properties of the matrix are expected to be rather different from those of the bulk resin. A plane stress micromechanical model was developed to retrieve the in situ elastic-plastic properties of Narmco 5260 and Amoco 8320 matrices from measured elastic-plastic properties of IM7/5260 and IM7/8320 advance composites. In the micromechanical model, the fiber was assumed to be orthotropically elastic and the matrix to be orthotropic in elastic and plastic properties. The results indicate that both in situ elastic and plastic properties of the matrices are orthotropic.

  12. [INVITED] New advances in polymer fiber Bragg gratings

    NASA Astrophysics Data System (ADS)

    Nogueira, Rogério; Oliveira, Ricardo; Bilro, Lúcia; Heidarialamdarloo, Jamshid

    2016-04-01

    During the last years, fiber Bragg gratings (FBGs) written in polymer optical fibers (POFs) have been pointed as an interesting alternative to silica FBGs for applications in sensors and in optical access networks. In order to use such components in real applications, the manipulation of POFs, as well as the increase of quality in the production of FBGs has to be achieved. In this article some of the recent advances regarding these two aspects are reported and include recent developments to produce smooth POFs end face with high quality, benefiting the current splicing process and the inscription of high quality FBGs in a few seconds. Furthermore, additional characterizations to strain, temperature, pressure, and humidity are also shown.

  13. Development of advanced fuel cell system

    NASA Technical Reports Server (NTRS)

    Grevstad, P. E.

    1972-01-01

    Weight, life and performance characteristics optimization of hydrogen-oxygen fuel cell power systems were considered. A promising gold alloy cathode catalyst was identified and tested in a cell for 5,000 hours. The compatibility characteristics of candidate polymer structural materials were measured after exposure to electrolyte and water vapor for 8,000 hours. Lightweight cell designs were prepared and fabrication techniques to produce them were developed. Testing demonstrated that predicted performance was achieved. Lightweight components for passive product water removal and evaporative cooling of cells were demonstrated. Systems studies identified fuel cell powerplant concepts for meeting the requirements of advanced spacecraft.

  14. Advanced worker protection system

    SciTech Connect

    Caldwell, B.; Duncan, P.; Myers, J.

    1995-10-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project describes the development of an Advanced Worker Protection System (AWPS) which will include a life-support backpack with liquid air for cooling and as a supply of breathing gas, protective clothing, respirators, communications, and support equipment.

  15. ADVANCED WORKER PROTECTION SYSTEM

    SciTech Connect

    Judson Hedgehock

    2001-03-16

    From 1993 to 2000, OSS worked under a cost share contract from the Department of Energy (DOE) to develop an Advanced Worker Protection System (AWPS). The AWPS is a protective ensemble that provides the user with both breathing air and cooling for a NIOSH-rated duration of two hours. The ensemble consists of a liquid air based backpack, a Liquid Cooling Garment (LCG), and an outer protective garment. The AWPS project was divided into two phases. During Phase 1, OSS developed and tested a full-scale prototype AWPS. The testing showed that workers using the AWPS could work twice as long as workers using a standard SCBA. The testing also provided performance data on the AWPS in different environments that was used during Phase 2 to optimize the design. During Phase 1, OSS also performed a life-cycle cost analysis on a representative clean up effort. The analysis indicated that the AWPS could save the DOE millions of dollars on D and D activities and improve the health and safety of their workers. During Phase 2, OSS worked to optimize the AWPS design to increase system reliability, to improve system performance and comfort, and to reduce the backpack weight and manufacturing costs. To support this design effort, OSS developed and tested several different generations of prototype units. Two separate successful evaluations of the ensemble were performed by the International Union of Operation Engineers (IUOE). The results of these evaluations were used to drive the design. During Phase 2, OSS also pursued certifying the AWPS with the applicable government agencies. The initial intent during Phase 2 was to finalize the design and then to certify the system. OSS and Scott Health and Safety Products teamed to optimize the AWPS design and then certify the system with the National Institute of Occupational Health and Safety (NIOSH). Unfortunately, technical and programmatic difficulties prevented us from obtaining NIOSH certification. Despite the inability of NIOSH to certify

  16. Conducting polymer membranes as intelligent separation systems

    SciTech Connect

    Price, W.E.; Wallace, G.G.

    1994-12-31

    Conducting electroactive polymers such as polypyrroles, are emerging as excellent materials in which to base a generic technology for the development of intelligent material systems. They are easy to make and many different chemistries may be built in during synthesis by varying the polymer(s) used and the counterions incorporated. However, the unique feature about them is that they have dynamic chemical and physical properties which may be manipulated via changing the redox states after synthesis. This paper illustrates their potential using recent work on developing a new electro-membrane separation technology using free-standing polypyrrole films. These systems are shown to be capable of a high degree of permselectivity and controllable transport that may be turned on and off by application of potential to the conducting polymer membrane.

  17. Advanced Integrated Traction System

    SciTech Connect

    Greg Smith; Charles Gough

    2011-08-31

    The United States Department of Energy elaborates the compelling need for a commercialized competitively priced electric traction drive system to proliferate the acceptance of HEVs, PHEVs, and FCVs in the market. The desired end result is a technically and commercially verified integrated ETS (Electric Traction System) product design that can be manufactured and distributed through a broad network of competitive suppliers to all auto manufacturers. The objectives of this FCVT program are to develop advanced technologies for an integrated ETS capable of 55kW peak power for 18 seconds and 30kW of continuous power. Additionally, to accommodate a variety of automotive platforms the ETS design should be scalable to 120kW peak power for 18 seconds and 65kW of continuous power. The ETS (exclusive of the DC/DC Converter) is to cost no more than $660 (55kW at $12/kW) to produce in quantities of 100,000 units per year, should have a total weight less than 46kg, and have a volume less than 16 liters. The cost target for the optional Bi-Directional DC/DC Converter is $375. The goal is to achieve these targets with the use of engine coolant at a nominal temperature of 105C. The system efficiency should exceed 90% at 20% of rated torque over 10% to 100% of maximum speed. The nominal operating system voltage is to be 325V, with consideration for higher voltages. This project investigated a wide range of technologies, including ETS topologies, components, and interconnects. Each technology and its validity for automotive use were verified and then these technologies were integrated into a high temperature ETS design that would support a wide variety of applications (fuel cell, hybrids, electrics, and plug-ins). This ETS met all the DOE 2010 objectives of cost, weight, volume and efficiency, and the specific power and power density 2015 objectives. Additionally a bi-directional converter was developed that provides charging and electric power take-off which is the first step

  18. ADVANCED TURBINE SYSTEMS PROGRAM

    SciTech Connect

    Sy Ali

    2002-03-01

    The market for power generation equipment is undergoing a tremendous transformation. The traditional electric utility industry is restructuring, promising new opportunities and challenges for all facilities to meet their demands for electric and thermal energy. Now more than ever, facilities have a host of options to choose from, including new distributed generation (DG) technologies that are entering the market as well as existing DG options that are improving in cost and performance. The market is beginning to recognize that some of these users have needs beyond traditional grid-based power. Together, these changes are motivating commercial and industrial facilities to re-evaluate their current mix of energy services. One of the emerging generating options is a new breed of advanced fuel cells. While there are a variety of fuel cell technologies being developed, the solid oxide fuel cells (SOFC) and molten carbonate fuel cells (MCFC) are especially promising, with their electric efficiency expected around 50-60 percent and their ability to generate either hot water or high quality steam. In addition, they both have the attractive characteristics of all fuel cells--relatively small siting footprint, rapid response to changing loads, very low emissions, quiet operation, and an inherently modular design lending itself to capacity expansion at predictable unit cost with reasonably short lead times. The objectives of this project are to:(1) Estimate the market potential for high efficiency fuel cell hybrids in the U.S.;(2) Segment market size by commercial, industrial, and other key markets;(3) Identify and evaluate potential early adopters; and(4) Develop results that will help prioritize and target future R&D investments. The study focuses on high efficiency MCFC- and SOFC-based hybrids and competing systems such as gas turbines, reciprocating engines, fuel cells and traditional grid service. Specific regions in the country have been identified where these

  19. Polymer system for gettering hydrogen

    DOEpatents

    Shepodd, Timothy Jon; Whinnery, LeRoy L.

    2000-01-01

    A novel composition comprising organic polymer molecules having carbon-carbon double bonds, for removing hydrogen from the atmosphere within enclosed spaces. Organic polymers molecules containing carbon-carbon double bonds throughout their structures, preferably polybutadiene, polyisoprene and derivatives thereof, intimately mixed with an insoluble catalyst composition, comprising a hydrogenation catalyst and a catalyst support, preferably Pd supported on carbon, provide a hydrogen getter composition useful for removing hydrogen from enclosed spaces even in the presence of contaminants such as common atmospheric gases, water vapor, carbon dioxide, ammonia, oil mists, and water. The hydrogen getter composition disclosed herein is particularly useful for removing hydrogen from enclosed spaces containing potentially explosive mixtures of hydrogen and oxygen.

  20. Advanced Microturbine Systems

    SciTech Connect

    Rosfjord, T; Tredway, W; Chen, A; Mulugeta, J; Bhatia, T

    2008-12-31

    In July 2000, the United Technologies Research Center (UTRC) was one of five recipients of a US Department of Energy contract under the Advanced Microturbine System (AMS) program managed by the Office of Distributed Energy (DE). The AMS program resulted from several government-industry workshops that recognized that microturbine systems could play an important role in improving customer choice and value for electrical power. That is, the group believed that electrical power could be delivered to customers more efficiently and reliably than the grid if an effective distributed energy strategy was followed. Further, the production of this distributed power would be accomplished with less undesirable pollutants of nitric oxides (NOx) unburned hydrocarbons (UHC), and carbon monoxide (CO). In 2000, the electrical grid delivered energy to US customers at a national average of approximately 32% efficiency. This value reflects a wide range of powerplants, but is dominated by older, coal burning stations that provide approximately 50% of US electrical power. The grid efficiency is also affected by transmission and distribution (T&D) line losses that can be significant during peak power usage. In some locations this loss is estimated to be 15%. Load pockets can also be so constrained that sufficient power cannot be transmitted without requiring the installation of new wires. New T&D can be very expensive and challenging as it is often required in populated regions that do not want above ground wires. While historically grid reliability has satisfied most customers, increasing electronic transactions and the computer-controlled processes of the 'digital economy' demand higher reliability. For them, power outages can be very costly because of transaction, work-in-progress, or perishable commodity losses. Powerplants that produce the grid electrical power emit significant levels of undesirable NOx, UHC, and CO pollutants. The level of emission is quoted as either a technology

  1. Polymer filtration systems for dilute metal ion recovery

    SciTech Connect

    Smith, B.F.; Robison, T.W.; Jarvinen, G.D.

    1998-12-01

    Scientists at Los Alamos National Laboratory have developed a metal recovery system that meets the global treatment demands for all kinds of industrial and metal-processing streams. The Polymer Filtration (PF) System--a process that is easily operated and robust--offers metal-finishing businesses a convenient and inexpensive way to recover and recycle metal ions in-house, thus reducing materials costs, waste removal costs, and industrial liability. As a valuable economic and environmental asset, the PF System has been named a winner of a 1995 R and D 100 Award. These awards are presented annually by R and D Magazine to the one hundred most significant technical innovations of the year. The PF System is based on the use of water-soluble metal-binding polymers and on advanced ultrafiltration membranes. Customers for this technology will receive new soluble polymers, especially formulated for their waste stream, and the complete PF processing unit: a reaction reservoir, pumps, plumbing, controls, and the advanced ultrafiltration membranes, all in a skid mounted frame. Metal-bearing waste water is treated in the reaction reservoir, where the polymer binds with the metal ions under balanced acid/base conditions. The reservoir fluid is then pumped through the ultrafiltration system--a cartridge packed with ultrafiltration membranes shaped in hollow fibers. As the fluid travels inside the fiber, water and other small molecules--simple salts such as calcium and sodium, for example--pass through the porous membrane walls of the fibers and are discharged through the outlet as permeate. The polymer-bound metal, which is too large to pass through the pores, is both purified and concentrated inside the hollow fibers and is returned to the fluid reservoir for further waste water treatment.

  2. The NASA "PERS" Program: Solid Polymer Electrolyte Development for Advanced Lithium-Based Batteries

    NASA Technical Reports Server (NTRS)

    Baldwin, Richard S.; Bennett, William R.

    2007-01-01

    In fiscal year 2000, The National Aeronautics and Space Administration (NASA) and the Air Force Research Laboratory (AFRL) established a collaborative effort to support the development of polymer-based, lithium-based cell chemistries and battery technologies to address the next generation of aerospace applications and mission needs. The ultimate objective of this development program, which was referred to as the Polymer Energy Rechargeable System (PERS), was to establish a world-class technology capability and U.S. leadership in polymer-based battery technology for aerospace applications. Programmatically, the PERS initiative exploited both interagency collaborations to address common technology and engineering issues and the active participation of academia and private industry. The initial program phases focused on R&D activities to address the critical technical issues and challenges at the cell level. Out of a total of 38 proposals received in response to a NASA Research Announcement (NRA) solicitation, 18 proposals (13 contracts and 5 grants) were selected for initial award to address these technical challenges. Brief summaries of technical approaches, results and accomplishments of the PERS Program development efforts are presented. With Agency support provided through FY 2004, the PERS Program efforts were concluded in 2005, as internal reorganizations and funding cuts resulted in shifting programmatic priorities within NASA. Technically, the PERS Program participants explored, to various degrees over the lifetime of the formal program, a variety of conceptual approaches for developing and demonstrating performance of a viable advanced solid polymer electrolyte possessing the desired attributes, as well as several participants addressing all components of an integrated cell configuration. Programmatically, the NASA PERS Program was very successful, even though the very challenging technical goals for achieving a viable solid polymer electrolyte material or

  3. Advanced border monitoring sensor system

    NASA Astrophysics Data System (ADS)

    Knobler, Ronald A.; Winston, Mark A.

    2008-04-01

    McQ has developed an advanced sensor system tailored for border monitoring that has been delivered as part of the SBInet program for the Department of Homeland Security (DHS). Technology developments that enhance a broad range of features are presented in this paper, which address the overall goal of the system to improving unattended ground sensor system capabilities for border monitoring applications. Specifically, this paper addresses a system definition, communications architecture, advanced signal processing to classify targets, and distributed sensor fusion processing.

  4. Advanced satellite communication system

    NASA Technical Reports Server (NTRS)

    Staples, Edward J.; Lie, Sen

    1992-01-01

    The objective of this research program was to develop an innovative advanced satellite receiver/demodulator utilizing surface acoustic wave (SAW) chirp transform processor and coherent BPSK demodulation. The algorithm of this SAW chirp Fourier transformer is of the Convolve - Multiply - Convolve (CMC) type, utilizing off-the-shelf reflective array compressor (RAC) chirp filters. This satellite receiver, if fully developed, was intended to be used as an on-board multichannel communications repeater. The Advanced Communications Receiver consists of four units: (1) CMC processor, (2) single sideband modulator, (3) demodulator, and (4) chirp waveform generator and individual channel processors. The input signal is composed of multiple user transmission frequencies operating independently from remotely located ground terminals. This signal is Fourier transformed by the CMC Processor into a unique time slot for each user frequency. The CMC processor is driven by a waveform generator through a single sideband (SSB) modulator. The output of the coherent demodulator is composed of positive and negative pulses, which are the envelopes of the chirp transform processor output. These pulses correspond to the data symbols. Following the demodulator, a logic circuit reconstructs the pulses into data, which are subsequently differentially decoded to form the transmitted data. The coherent demodulation and detection of BPSK signals derived from a CMC chirp transform processor were experimentally demonstrated and bit error rate (BER) testing was performed. To assess the feasibility of such advanced receiver, the results were compared with the theoretical analysis and plotted for an average BER as a function of signal-to-noise ratio. Another goal of this SBIR program was the development of a commercial product. The commercial product developed was an arbitrary waveform generator. The successful sales have begun with the delivery of the first arbitrary waveform generator.

  5. Improving reservoir conformance using gelled polymer systems

    SciTech Connect

    Green, D.W.; Willhite, G.P.

    1993-04-09

    The general objectives are to (1) to identify and develop gelled polymer systems which have potential to improve reservoir conformance of fluid displacement processes, (2) to determine the performance of these systems in bulk and in porous media, and (3) to develop methods to predict the capability of these systems to recover oil from petroleum reservoirs. This work focuses on three types of gel systems - an aqueous polysaccharide (KUSPI) system that gels as a function of pH, the chromium-based system where polyacrylamide and xanthan are crosslinked by CR(III) and an organic crosslinked system. Development of the KUSPI system and evaluation and identification of a suitable organic crosslinked system will be done. The laboratory research is directed at the fundamental understanding of the physics and chemistry of the gelation process in bulk form and in porous media. This knowledge will be used to develop conceptual and mathematical models of the gelation process. Mathematical models will then be extended to predict the performance of gelled polymer treatments in oil reservoirs. Accomplishments for this period are presented for the following tasks: development and selection of gelled polymer systems, physical and chemical characterization of gel systems; and mathematical modeling of gel systems.

  6. Improving reservoir conformance using gelled polymer systems

    SciTech Connect

    Green, D.W.; Willhite, P.G.

    1992-12-25

    The general objectives are to (1) to identify and develop gelled polymer systems which have potential to improve reservoir conformance of fluid displacement processes, (2) to determine the performance of these systems in bulk and in porous media, and (3) to develop methods to predict the capability of these systems to recover oil from petroleum reservoirs. This work focuses on three types of gel systems -- an aqueous polysaccharide (KUSP1) system that gels as a function of pH, the chromium-based system where polyacrylamide and xanthan are crosslinked by Cr(III) and an organic crosslinked system. Development of the KUSP1 system and evaluation and, identification of the organic crosslinked system will be conducted. The laboratory research is directed at the fundamental understanding of the physics and chemistry of the gelation process in bulk form and in porous media. This knowledge will be used to develop conceptual and mathematical models of the gelation process. Mathematical models will then be extended to predict the performance of gelled polymer treatments in oil reservoirs. Progress report are presented for the following tasks: Development and selection of gelled polymer systems; physical and chemical characterization of gel systems; and mathematical modelling of gel systems.

  7. Recent Advances in Thermoplastic Puncture-Healing Polymers

    NASA Technical Reports Server (NTRS)

    Gordon, K. L.; Working, D. C.; Wise, K. E.; Bogert, P. B.; Britton, S. M.; Topping, C.C.; Smith, J. Y.; Siochi, E. J.

    2009-01-01

    Self-healing materials provide a route for enhanced damage tolerance in materials for aerospace applications. In particular, puncture-healing upon impact has the potential to mitigate significant damage caused by high velocity micrometeoroid impacts. This type of material also has the potential to improve damage tolerance in load bearing structures to enhance vehicle health and aircraft durability. The materials being studied are those capable of instantaneous puncture healing, providing a mechanism for mechanical property retention in lightweight structures. These systems have demonstrated healing capability following penetration of fast moving projectiles -- velocities that range from 9 mm bullets shot from a gun (approx.330 m/sec) to close to micrometeoroid debris velocities of 4800 m/sec. In this presentation, we report on a suite of polymeric materials possessing this characteristic. Figure 1 illustrates the puncture healing concept. Puncture healing in these materials is dependent upon how the combination of a polymer's viscoelastic properties responds to the energy input resulting from the puncture event. Projectile penetration increases the temperature in the vicinity of the impact. Self-healing behavior occurs following puncture, whereby energy must be transferred to the material during impact both elastically and inelastically, thus establishing two requirements for puncture healing to occur: a.) The need for the puncture event to produce a local melt state in the polymer material and b.) The molten material has to have sufficient melt elasticity to snap back and close the hole. 1,2 Previous ballistic testing studies revealed that Surlyn materials warmed up to a temperature approx.98 C during projectile puncture (3 C higher than it s melting temperature). 1,2 The temperature increase produces a localized flow state and the melt elasticity to snap back thus sealing the hole. Table 1 lists the commercially polymers studied here, together with their physical

  8. Zoom optical system using tunable polymer lens

    NASA Astrophysics Data System (ADS)

    Liang, Dan; Wang, Xuan Yin

    2016-07-01

    This paper demonstrated a zoom optical system with variable magnification based on the tunable polymer lens. The designed system mainly consists of two polymer lenses, voice coil motors, a doublet lens and CMOS chip. The zoom magnification can be adjusted by altering the focal length of the two elastic polymer lenses synergistically through controlling the output displacement of the voice coil motor. A static doublet lens in combination with the polymer lenses stabilize the image plane at the CMOS chip. The optical structure of the zoom system is presented, as well as a detailed description including the lens materials and fabrication process. Images with each zoom magnification are captured, and the Spot diagram and MTF are simulated using Zemax software. A change in magnification from 0.13×to 8.44×is demonstrated within the tiny 0.4 mm variation of the displacement load, and produce a 16.1×full range of magnification experimentally. Simulation analyses show that all the radii of the spot diagram under different magnifications are less than 11.3 um, and the modulation transfer function reaches 107 line pairs per mm. The designed optical system shows the potential for developing stable, integrated, and low-cost zoom systems with large magnification range.

  9. Recent Advances in Glycerol Polymers: Chemistry and Biomedical Applications

    PubMed Central

    Zhang, Heng

    2015-01-01

    Glycerol polymers are attracting increased attention due to the diversity of polymer compositions and architectures available. This article provides a brief chronological review on the current status of these polymers along with representative examples of their use for biomedical applications. First, we describe the underlying chemistry of glycerol, which provides access to a range of monomers for subsequent polymerizations. We then review the various synthetic methodologies to prepare glycerol-based polymers including polyethers, polycarbonates, polyesters, and so forth. Next, we describe several biomedical applications where glycerol polymers are being investigated including carriers for drug delivery, sealants or coatings for tissue repair, and agents possessing antibacterial activity. Fourth, we describe the growing market opportunity for the use of polymers in medicine. Finally we conclude and summarize the findings, as well as discuss potential opportunities for continued research efforts. PMID:25308354

  10. Advanced space recovery systems

    NASA Technical Reports Server (NTRS)

    Wailes, William K.

    1989-01-01

    The design evolution of a space recovery system designed by a NASA-contracted study is described, with particular attention given to the design of a recovery system for a propulsion/avionics module (P/AM), which weighs 60,000 lb at the recovery initiation and achieves subsonic terminal descent at or above 50,000 ft msl. The components of the recovery system concept are described together with the operational sequences of the recovery. The recovery system concept offers low cost, low weight, good performance, a potential for pinpoint landing, and an operational flexibility.

  11. Thermal diffusivity measurement system applied to polymers

    NASA Astrophysics Data System (ADS)

    Abad, B.; Díaz-Chao, P.; Almarza, A.; Amantia, D.; Vázquez-Campos, S.; Isoda, Y.; Shinohara, Y.; Briones, F.; Martín-González, M. S.

    2012-06-01

    In the search for cleaner energy sources, the improvement of the efficiency of the actual ones appears as a primary objective. In this way, thermoelectric materials, which are able to convert wasted heat into electricity, are reveal as an interesting way to improve efficiency of car engines, for example. Cost-effective energy harvesting from thermoelectric devices requires materials with high electrical conductivities and Seebeck coefficient, but low thermal conductivity. Conductive polymers can fulfil these conditions if they are doped appropriately. One of the most promising polymers is Polyaniline. In this work, the thermal conductivity of the polyaniline and mixtures of polyaniline with nanoclays has been studied, using a new experimental set-up developed in the lab. The novel system is based on the steady-state method and it is used to obtain the thermal diffusivity of the polymers and the nanocomposites.

  12. Polymer Energy Rechargeable System (PERS) Development Program

    NASA Technical Reports Server (NTRS)

    Baldwin, Richard S.; Manzo, Michelle A.; Dalton, Penni J.; Marsh, Richard A.; Surampudi, Rao

    2001-01-01

    The National Aeronautics and Space Administration (NASA) and the Air Force Research Laboratory (AFRL) have recently established a collaborative effort to support the development of polymer-based, lithium-based cell chemistries and battery technologies to address the next generation of aerospace applications and mission needs. The overall objective of this development program, which is referred to as PERS, Polymer Energy Rechargeable System, is to establish a world-class technology capability and U.S. leadership in polymer-based battery technology for aerospace applications. Programmatically, the PERS initiative will exploit both interagency collaborations to address common technology and engineering issues and the active participation of academia and private industry. The initial program phases will focus on R&D activities to address the critical technical issues and challenges at the cell level.

  13. Advanced training systems

    NASA Technical Reports Server (NTRS)

    Savely, Robert T.; Loftin, R. Bowen

    1990-01-01

    Training is a major endeavor in all modern societies. Common training methods include training manuals, formal classes, procedural computer programs, simulations, and on-the-job training. NASA's training approach has focussed primarily on on-the-job training in a simulation environment for both crew and ground based personnel. NASA must explore new approaches to training for the 1990's and beyond. Specific autonomous training systems are described which are based on artificial intelligence technology for use by NASA astronauts, flight controllers, and ground based support personnel that show an alternative to current training systems. In addition to these specific systems, the evolution of a general architecture for autonomous intelligent training systems that integrates many of the features of traditional training programs with artificial intelligence techniques is presented. These Intelligent Computer Aided Training (ICAT) systems would provide much of the same experience that could be gained from the best on-the-job training.

  14. Nondestructive Evaluation of Advanced Fiber Reinforced Polymer Matrix Composites: A Technology Assessment

    NASA Technical Reports Server (NTRS)

    Yolken, H. Thomas; Matzkanin, George A.

    2009-01-01

    Because of their increasing utilization in structural applications, the nondestructive evaluation (NDE) of advanced fiber reinforced polymer composites continues to receive considerable research and development attention. Due to the heterogeneous nature of composites, the form of defects is often very different from a metal and fracture mechanisms are more complex. The purpose of this report is to provide an overview and technology assessment of the current state-of-the-art with respect to NDE of advanced fiber reinforced polymer composites.

  15. Surface properties of functional polymer systems

    NASA Astrophysics Data System (ADS)

    Wong, Derek

    Polymer surface modification typically involves blending with other polymers or chemical modification of the parent polymer. Such strategies inevitably result in polymer systems that are spatially and chemically heterogeneous, and which exhibit the phenomenon of surface segregation. This work investigates the effects of chain architecture on the surface segregation behavior of such functionally modified polymers using a series of end- and center-fluorinated poly(D,L-lactide). Surface segregation of the fluorinated functional groups was observed in both chain architectures via AMPS and water contact angle. Higher surface segregation was noted for functional groups located at the chain end as opposed to those in the middle of the chain. A self-consistent mean-field lattice theory was used to model the composition depth profiles of functional groups and excellent agreement was found between the model predictions and the experimental AMPS data in both chain architectures. Polymer properties are also in general dependent on both time and temperature, and exhibit a range of relaxation times in response to environmental stimuli. This behavior arises from the characteristic frequencies of molecular motions of the polymer chain and the interrelationship between time and temperature has been widely established for polymer bulk properties. There is evidence that surface properties also respond in a manner that is time and temperature dependent and that this dependence may not be the same as that observed for bulk properties. AMPS and water contact angle experiments were used to investigate the surface reorganization behavior of functional groups using a series of anionically synthesized end-fluorinated and end-carboxylated poly(styrene). It was found that both types of functional end-groups reorganized upon a change in the polarity of the surface environment in order to minimize the surface free energy. ADXPS and contact angle results suggest that the reorganization depth was

  16. Advanced cement solidification system

    SciTech Connect

    Nakashima, T.; Kuribayashi, H.; Todo, F.

    1993-12-31

    In order to easily and economically store and transport radioactive waste generated at nuclear power stations, it is essential to reduce the waste volume to the maximum extent. It is also necessary to transform the waste into a stable form for final disposal which will maintain its chemical and physical stability over a long period of time. For this purpose, the Advanced Cement Solidification Process (AC-process) was developed. The AC-process, which utilizes portland cement, can be applied to several kinds of waste such as boric acid waste, laboratory drain waste, incineration ash and spent ion exchange resin. In this paper, the key point of the AC-process, the pretreatment concept for each waste, is described. The AC-process has been adopted for two Japanese PWR stations: the Genkai Nuclear Power Station (Kyushu Electric Power Co.) and the Ikata Nuclear Power Station (Shikoku Electric Power Co.). Construction work has almost finished and commissioning tests are under way at both power stations.

  17. Polymer, metal and ceramic matrix composites for advanced aircraft engine applications

    NASA Technical Reports Server (NTRS)

    Mcdanels, D. L.; Serafini, T. T.; Dicarlo, J. A.

    1985-01-01

    Advanced aircraft engine research within NASA Lewis is being focused on propulsion systems for subsonic, supersonic, and hypersonic aircraft. Each of these flight regimes requires different types of engines, but all require advanced materials to meet their goals of performance, thrust-to-weight ratio, and fuel efficiency. The high strength/weight and stiffness/weight properties of resin, metal, and ceramic matrix composites will play an increasingly key role in meeting these performance requirements. At NASA Lewis, research is ongoing to apply graphite/polyimide composites to engine components and to develop polymer matrices with higher operating temperature capabilities. Metal matrix composites, using magnesium, aluminum, titanium, and superalloy matrices, are being developed for application to static and rotating engine components, as well as for space applications, over a broad temperature range. Ceramic matrix composites are also being examined to increase the toughness and reliability of ceramics for application to high-temperature engine structures and components.

  18. Advanced synchronous luminescence system

    DOEpatents

    Vo-Dinh, Tuan

    1997-01-01

    A method and apparatus for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition.

  19. Advanced Data Acquisition Systems

    NASA Technical Reports Server (NTRS)

    Perotti, J.

    2003-01-01

    Current and future requirements of the aerospace sensors and transducers field make it necessary for the design and development of new data acquisition devices and instrumentation systems. New designs are sought to incorporate self-health, self-calibrating, self-repair capabilities, allowing greater measurement reliability and extended calibration cycles. With the addition of power management schemes, state-of-the-art data acquisition systems allow data to be processed and presented to the users with increased efficiency and accuracy. The design architecture presented in this paper displays an innovative approach to data acquisition systems. The design incorporates: electronic health self-check, device/system self-calibration, electronics and function self-repair, failure detection and prediction, and power management (reduced power consumption). These requirements are driven by the aerospace industry need to reduce operations and maintenance costs, to accelerate processing time and to provide reliable hardware with minimum costs. The project's design architecture incorporates some commercially available components identified during the market research investigation like: Field Programmable Gate Arrays (FPGA) Programmable Analog Integrated Circuits (PAC IC) and Field Programmable Analog Arrays (FPAA); Digital Signal Processing (DSP) electronic/system control and investigation of specific characteristics found in technologies like: Electronic Component Mean Time Between Failure (MTBF); and Radiation Hardened Component Availability. There are three main sections discussed in the design architecture presented in this document. They are the following: (a) Analog Signal Module Section, (b) Digital Signal/Control Module Section and (c) Power Management Module Section. These sections are discussed in detail in the following pages. This approach to data acquisition systems has resulted in the assignment of patent rights to Kennedy Space Center under U.S. patent # 6

  20. Advanced extravehicular protective systems

    NASA Technical Reports Server (NTRS)

    Sutton, J. G.; Heimlich, P. F.; Tepper, E. H.

    1972-01-01

    New technologies are identified and recommended for developing a regenerative portable life support system that provides protection for extravehicular human activities during long duration missions on orbiting space stations, potential lunar bases, and possible Mars landings. Parametric subsystems analyses consider: thermal control, carbon dioxide control, oxygen supply, power supply, contaminant control, humidity control, prime movers, and automatic temperature control.

  1. Advanced synchronous luminescence system

    DOEpatents

    Vo-Dinh, T.

    1997-02-04

    A method and apparatus are disclosed for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition. 14 figs.

  2. Power Systems Advanced Research

    SciTech Connect

    California Institute of Technology

    2007-03-31

    In the 17 quarters of the project, we have accomplished the following milestones - first, construction of the three multiwavelength laser scattering machines for different light scattering study purposes; second, build up of simulation software package for simulation of field and laboratory particulates matters data; third, carried out field online test on exhaust from combustion engines with our laser scatter system. This report gives a summary of the results and achievements during the project's 16 quarters period. During the 16 quarters of this project, we constructed three multiwavelength scattering instruments for PM2.5 particulates. We build up a simulation software package that could automate the simulation of light scattering for different combinations of particulate matters. At the field test site with our partner, Alturdyne, Inc., we collected light scattering data for a small gas turbine engine. We also included the experimental data feedback function to the simulation software to match simulation with real field data. The PM scattering instruments developed in this project involve the development of some core hardware technologies, including fast gated CCD system, accurately triggered Passively Q-Switched diode pumped lasers, and multiwavelength beam combination system. To calibrate the scattering results for liquid samples, we also developed the calibration system which includes liquid PM generator and size sorting instrument, i.e. MOUDI. In this report, we give the concise summary report on each of these subsystems development results.

  3. Westinghouse advanced particle filter system

    SciTech Connect

    Lippert, T.E.; Bruck, G.J.; Sanjana, Z.N.; Newby, R.A.

    1995-11-01

    Integrated Gasification Combined Cycles (IGCC), Pressurized Fluidized Bed Combustion (PFBC) and Advanced PFBC (APFB) are being developed and demonstrated for commercial power generation application. Hot gas particulate filters are key components for the successful implementation of IGCC, PFBC and APFB in power generation gas turbine cycles. The objective of this work is to develop and qualify through analysis and testing a practical hot gas ceramic barrier filter system that meets the performance and operational requirements of these advanced, solid fuel power generation cycles.

  4. Development of advanced fuel cell system, phase 2

    NASA Technical Reports Server (NTRS)

    Handley, L. M.; Meyer, A. P.; Bell, W. F.

    1973-01-01

    A multiple task research and development program was performed to improve the weight, life, and performance characteristics of hydrogen-oxygen alkaline fuel cells for advanced power systems. Development and characterization of a very stable gold alloy catalyst was continued from Phase I of the program. A polymer material for fabrication of cell structural components was identified and its long term compatibility with the fuel cell environment was demonstrated in cell tests. Full scale partial cell stacks, with advanced design closed cycle evaporative coolers, were tested. The characteristics demonstrated in these tests verified the feasibility of developing the engineering model system concept into an advanced lightweight long life powerplant.

  5. Advanced flight control system study

    NASA Technical Reports Server (NTRS)

    Mcgough, J.; Moses, K.; Klafin, J. F.

    1982-01-01

    The architecture, requirements, and system elements of an ultrareliable, advanced flight control system are described. The basic criteria are functional reliability of 10 to the minus 10 power/hour of flight and only 6 month scheduled maintenance. A distributed system architecture is described, including a multiplexed communication system, reliable bus controller, the use of skewed sensor arrays, and actuator interfaces. Test bed and flight evaluation program are proposed.

  6. Recent advances in research on carbon nanotube-polymer composites.

    PubMed

    Byrne, Michele T; Gun'ko, Yurii K

    2010-04-18

    Carbon nanotubes (CNTs) demonstrate remarkable electrical, thermal, and mechanical properties, which allow a number of exciting potential applications. In this article, we review the most recent progress in research on the development of CNT-polymer composites, with particular attention to their mechanical and electrical (conductive) properties. Various functionalization and fabrication approaches and their role in the preparation of CNT-polymer composites with improved mechanical and electrical properties are discussed. We tabulate the most recent values of Young's modulus and electrical conductivities for various CNT-polymer composites and compare the effectiveness of different processing techniques. Finally, we give a future outlook for the development of CNT-polymer composites as potential alternative materials for various applications, including flexible electrodes in displays, electronic paper, antistatic coatings, bullet-proof vests, protective clothing, and high-performance composites for aircraft and automotive industries. PMID:20496401

  7. Advanced Dewatering Systems Development

    SciTech Connect

    R.H. Yoon; G.H. Luttrell

    2008-07-31

    A new fine coal dewatering technology has been developed and tested in the present work. The work was funded by the Solid Fuels and Feedstocks Grand Challenge PRDA. The objective of this program was to 'develop innovative technical approaches to ensure a continued supply of environmentally sound solid fuels for existing and future combustion systems with minimal incremental fuel cost.' Specifically, this solicitation is aimed at developing technologies that can (i) improve the efficiency or economics of the recovery of carbon when beneficiating fine coal from both current production and existing coal slurry impoundments and (ii) assist in the greater utilization of coal fines by improving the handling characteristics of fine coal via dewatering and/or reconstitution. The results of the test work conducted during Phase I of the current project demonstrated that the new dewatering technologies can substantially reduce the moisture from fine coal, while the test work conducted during Phase II successfully demonstrated the commercial viability of this technology. It is believed that availability of such efficient and affordable dewatering technology is essential to meeting the DOE's objectives.

  8. Advanced coating lining systems for challenging chemical environments

    SciTech Connect

    Brupbacher, J.M.; Stiles, J.E.

    1997-08-01

    Advanced coatings and coating lining systems are being increasingly used by industry to protect process equipment in challenging chemical environments. This includes not only severe corrosive liquors encountered in many Chemical Process Industry streams, but also the high purity process liquors and rinse systems of the pharmaceutical and microelectronics industries. This paper discusses the design options for optimizing the performance of fluoropolymer-based coating systems for industry-specific applications such as these. Design factors discussed will include surface pre-treatment options, chemical and mechanical bonding systems, field-proven and advanced polymer barrier coatings, homogeneous and graded polymer barrier stacks, and imbedded permeation barriers. The processing techniques for applying engineered coatings will be discussed since processing also plays an important role in the design options available to individual coating applicators and ultimate performance of the coating system applied. Several case studies will be presented and discussed.

  9. Thiol-vinyl systems as shape memory polymers and novel two-stage reactive polymer systems

    NASA Astrophysics Data System (ADS)

    Nair, Devatha P.

    2011-12-01

    The focus of this research was to formulate, characterize and tailor the reaction methodologies and material properties of thiol-vinyl systems to develop novel polymer platforms for a range of engineering applications. Thiol-ene photopolymers were demonstrated to exhibit several advantageous characteristics for shape memory polymer systems for a range of biomedical applications. The thiol-ene shape memory polymer systems were tough and flexible as compared to the acrylic control systems with glass transition temperatures between 30 and 40 °C; ideal for actuation at body temperature. The thiol-ene polymers also exhibited excellent shape fixity and a rapid and distinct shape memory actuation response along with free strain recoveries of greater than 96% and constrained stress recoveries of 100%. Additionally, two-stage reactive thiol-acrylate systems were engineered as a polymer platform technology enabling two independent sets of polymer processing and material properties. There are distinct advantages to designing polymer systems that afford two distinct sets of material properties -- an intermediate polymer that would enable optimum handling and processing of the material (stage 1), while maintaining the ability to tune in different, final properties that enable the optimal functioning of the polymeric material (stage 2). To demonstrate the range of applicability of the two-stage reactive systems, three specific applications were demonstrated; shape memory polymers, lithographic impression materials, and optical materials. The thiol-acrylate reactions exhibit a wide range of application versatility due to the range of available thiol and acrylate monomers as well as reaction mechanisms such as Michael Addition reactions and free radical polymerizations. By designing a series of non-stoichiometeric thiol-acrylate systems, a polymer network is initially formed via a base catalyzed 'click' Michael addition reaction. This self-limiting reaction results in a Stage 1

  10. Advanced spacecraft fuel cell systems

    NASA Technical Reports Server (NTRS)

    Thaller, L. H.

    1972-01-01

    The development and characteristics of advanced spacecraft fuel cell systems are discussed. The system is designed to operate on low pressure, propulsion grade hydrogen and oxygen. The specific goals are 10,000 hours of operation with refurbishment, 20 pounds per kilowatt at a sustained power of 7 KW, and 21 KW peaking capability for durations of two hours. The system rejects waste heat to the spacecraft cooling system at power levels up to 7 KW. At higher powers, the system automatically transfers to open cycle operation with overboard steam venting.

  11. Final Technical Report - Advanced Optical Sensors to Minimize Energy Consumption in Polymer Extrusion Processes

    SciTech Connect

    Susan J. Foulk

    2012-07-24

    Project Objective: The objectives of this study are to develop an accurate and stable on-line sensor system to monitor color and composition on-line in polymer melts, to develop a scheme for using the output to control extruders to eliminate the energy, material and operational costs of off-specification product, and to combine or eliminate some extrusion processes. Background: Polymer extrusion processes are difficult to control because the quality achieved in the final product is complexly affected by the properties of the extruder screw, speed of extrusion, temperature, polymer composition, strength and dispersion properties of additives, and feeder system properties. Extruder systems are engineered to be highly reproducible so that when the correct settings to produce a particular product are found, that product can be reliably produced time after time. However market conditions often require changes in the final product, different products or grades may be processed in the same equipment, and feed materials vary from lot to lot. All of these changes require empirical adjustment of extruder settings to produce a product meeting specifications. Optical sensor systems that can continuously monitor the composition and color of the extruded polymer could detect process upsets, drift, blending oscillations, and changes in dispersion of additives. Development of an effective control algorithm using the output of the monitor would enable rapid corrections for changes in materials and operating conditions, thereby eliminating most of the scrap and recycle of current processing. This information could be used to identify extruder systems issues, diagnose problem sources, and suggest corrective actions in real-time to help keep extruder system settings within the optimum control region. Using these advanced optical sensor systems would give extruder operators real-time feedback from their process. They could reduce the amount of off-spec product produced and

  12. ADVANCED GAS TURBINE SYSTEMS RESEARCH

    SciTech Connect

    Unknown

    2002-04-01

    The activities of the Advanced Gas Turbine Systems Research (AGTSR) program for this reporting period are described in this quarterly report. The report is divided into discussions of Membership, Administration, Technology Transfer (Workshop/Education), Research and Miscellaneous Related Activity. Items worthy of note are presented in extended bullet format following the appropriate heading.

  13. ADVANCED GAS TURBINE SYSTEMS RESEARCH

    SciTech Connect

    Unknown

    2002-02-01

    The activities of the Advanced Gas Turbine Systems Research (AGTSR) program for this reporting period are described in this quarterly report. The report is divided into discussions of Membership, Administration, Technology Transfer (Workshop/Education), Research and Miscellaneous Related Activity. Items worthy of note are presented in extended bullet format following the appropriate heading.

  14. Do Membranes Dream of Electric Tubes? Advanced Membranes Using Carbon Nanotube - Polymer Nanocomposites

    NASA Astrophysics Data System (ADS)

    de Lannoy, Charles-Francois Pedro Claude Karolek Ghislain

    Membrane technologies represent an energy efficient, effective solution for treating municipal and commercial waters/wastewaters. Membranes are predominantly polymer-based and despite steady advances in polymeric materials, they continue to suffer from operational problems including biofouling and breakages. This work addresses these two disparate problems by developing novel CNT-polymer nanocomposite materials that contain variously functionalized carbon nanotubes (fCNTs) in low quantities (<0.5wt%). Several strategies have been employed to achieve highly functional CNT-polymer nanocomposite membranes including blend mixing, ionic charge association, and covalent cross-linking with monomer and oligomer constituents. These CNT-polymer nanocomposite membranes were compared to traditional polymer membranes across various properties including increased Young's Modulus, changes in surface hydrophilicity, fine control over molecular weight cut-off and flux, and surface electrical conductivity. Membranes with high surface electrical conductivity were further tested for their anti-biofouling properties. Finally, CNT stability and polymer compatibility were evaluated throughout membrane manufacture, use, and cleaning. The incorporation of CNTs mixed in bulk phase and linked through ionic associations in polymer matrices showed significant (50%) increases in Young's modulus for certain CNT functionalizations and derivatization percent. Membranes formed with high surface electrical conductivity demonstrated almost complete resistance to biofouling (> 95%) in long-term bacterially challenged experiments. CNTs and polymer mixtures that lacked covalent or ionic bonds were susceptible to significant (up to 10%) loss of CNTs during membrane non-solvent gelation and aggressive chemical cleaning treatment. Functionalized carbon nanotubes endow polymer membranes with their unique strength and electrically conductive properties. These added properties were demonstrated to greatly

  15. Recent advances in the chemical modification of unsaturated polymers

    NASA Technical Reports Server (NTRS)

    Schulz, D. N.; Turner, S. R.; Golub, M. A.

    1982-01-01

    The present discussion has the objective to update the most comprehensive reviews on the considered subject and to fill in the gaps of less complete, but more modern treatments. Only simple chemical functionalization or structural modification of unsaturated polymers are covered, and the literature of diene polymer modification since 1974 is emphasized. Attention is given to hydrogenation, halogenation and hydrohalogenation, cyclization, cis-trans isomerization, epoxidation, ene and other cycloaddition reactions, sulfonation, carboxylation, phosphonylation, sulfenyl chloride addition, carbene addition, metalation, and silylation. It is pointed out that modern synthetic reagents and catalysts have been advantageously employed to improve process and/or product quality. Synthetic techniques have been refined to allow the selective modification of specific polymer microstructures or blocks.

  16. Manufacturing Aspects of Advanced Polymer Composites for Automotive Applications

    NASA Astrophysics Data System (ADS)

    Friedrich, Klaus; Almajid, Abdulhakim A.

    2013-04-01

    Composite materials, in most cases fiber reinforced polymers, are nowadays used in many applications in which light weight and high specific modulus and strength are critical issues. The constituents of these materials and their special advantages relative to traditional materials are described in this paper. Further details are outlined regarding the present markets of polymer composites in Europe, and their special application in the automotive industry. In particular, the manufacturing of parts from thermoplastic as well as thermosetting, short and continuous fiber reinforced composites is emphasized.

  17. Advanced turboprop testbed systems study

    NASA Technical Reports Server (NTRS)

    Goldsmith, I. M.

    1982-01-01

    The proof of concept, feasibility, and verification of the advanced prop fan and of the integrated advanced prop fan aircraft are established. The use of existing hardware is compatible with having a successfully expedited testbed ready for flight. A prop fan testbed aircraft is definitely feasible and necessary for verification of prop fan/prop fan aircraft integrity. The Allison T701 is most suitable as a propulsor and modification of existing engine and propeller controls are adequate for the testbed. The airframer is considered the logical overall systems integrator of the testbed program.

  18. OPTIMIZATION OF ADVANCED FILTER SYSTEMS

    SciTech Connect

    R.A. Newby; G.J. Bruck; M.A. Alvin; T.E. Lippert

    1998-04-30

    Reliable, maintainable and cost effective hot gas particulate filter technology is critical to the successful commercialization of advanced, coal-fired power generation technologies, such as IGCC and PFBC. In pilot plant testing, the operating reliability of hot gas particulate filters have been periodically compromised by process issues, such as process upsets and difficult ash cake behavior (ash bridging and sintering), and by design issues, such as cantilevered filter elements damaged by ash bridging, or excessively close packing of filtering surfaces resulting in unacceptable pressure drop or filtering surface plugging. This test experience has focused the issues and has helped to define advanced hot gas filter design concepts that offer higher reliability. Westinghouse has identified two advanced ceramic barrier filter concepts that are configured to minimize the possibility of ash bridge formation and to be robust against ash bridges should they occur. The ''inverted candle filter system'' uses arrays of thin-walled, ceramic candle-type filter elements with inside-surface filtering, and contains the filter elements in metal enclosures for complete separation from ash bridges. The ''sheet filter system'' uses ceramic, flat plate filter elements supported from vertical pipe-header arrays that provide geometry that avoids the buildup of ash bridges and allows free fall of the back-pulse released filter cake. The Optimization of Advanced Filter Systems program is being conducted to evaluate these two advanced designs and to ultimately demonstrate one of the concepts in pilot scale. In the Base Contract program, the subject of this report, Westinghouse has developed conceptual designs of the two advanced ceramic barrier filter systems to assess their performance, availability and cost potential, and to identify technical issues that may hinder the commercialization of the technologies. A plan for the Option I, bench-scale test program has also been developed based

  19. Advanced Information Processing System (AIPS)

    NASA Technical Reports Server (NTRS)

    Pitts, Felix L.

    1993-01-01

    Advanced Information Processing System (AIPS) is a computer systems philosophy, a set of validated hardware building blocks, and a set of validated services as embodied in system software. The goal of AIPS is to provide the knowledgebase which will allow achievement of validated fault-tolerant distributed computer system architectures, suitable for a broad range of applications, having failure probability requirements of 10E-9 at 10 hours. A background and description is given followed by program accomplishments, the current focus, applications, technology transfer, FY92 accomplishments, and funding.

  20. Advanced Transport Operating Systems Program

    NASA Technical Reports Server (NTRS)

    White, John J.

    1990-01-01

    NASA-Langley's Advanced Transport Operating Systems Program employs a heavily instrumented, B 737-100 as its Transport Systems Research Vehicle (TRSV). The TRSV has been used during the demonstration trials of the Time Reference Scanning Beam Microwave Landing System (TRSB MLS), the '4D flight-management' concept, ATC data links, and airborne windshear sensors. The credibility obtainable from successful flight test experiments is often a critical factor in the granting of substantial commitments for commercial implementation by the FAA and industry. In the case of the TRSB MLS, flight test demonstrations were decisive to its selection as the standard landing system by the ICAO.

  1. Advances in Energy Management Systems

    SciTech Connect

    Horton, J.S.; Prince, B.; Sasson, A.M.; Wynne, W.T.; Trefny, F.; Cleveland, F.

    1986-08-01

    This paper is one of the series prepared for a special session to be held at PICA 85. The objective is to review the advances that have been made in Energy Management Systems and to obtain a more common agreement as to the usefulness and future of such systems. The paper contains a summary of five discussions of Energy Management Systems. These discussions focus on the major components of an Energy Management System and address important questions as to the usefulness, past developments, the current state-of-the-art, and needs in Energy Management Systems. Each author provides a different perspective of these systems. The discussions are intended to provide insight into Energy Management Systems, to solicit discussions, and to provide a forum for discussions of Energy Management System's developments and future needs.

  2. Thermoplastic polymer patterning without residual layer by advanced nanoimprinting schemes

    NASA Astrophysics Data System (ADS)

    Park, Hyunsoo; Cheng, Xing

    2009-06-01

    Nanoimprinting is a fast-growing technique for nanoscale patterning. One of the remaining issues in nanoimprinting is the removal of the residual layer after nanoimprinting. Traditionally the residual layer is removed by an oxygen reactive-ion etching (RIE) step. The need for a vacuum environment and dedicated equipment in this step lowers the throughput and increases the cost of the nanoimprinting process. It also prevents the possibility of patterning isolated functional polymers because oxygen RIE destroys the functional materials. In this work, novel nanoimprinting schemes are developed to nondestructively remove the residual layer in thermal nanoimprinting by solvent developing and dewetting. Combined with a transfer-bonding technique, three-dimensional polymer scaffolds are achieved. The techniques developed here eliminate the RIE step in thermal nanoimprinting and are compatible with roller nanoimprinting for large-scale patterning of polymer micro- or nanostructures. The technique also opens up new applications for nanoimprinting in patterning isolated conjugated polymers for organic electronic devices and circuits.

  3. Thermoplastic polymer patterning without residual layer by advanced nanoimprinting schemes.

    PubMed

    Park, Hyunsoo; Cheng, Xing

    2009-06-17

    Nanoimprinting is a fast-growing technique for nanoscale patterning. One of the remaining issues in nanoimprinting is the removal of the residual layer after nanoimprinting. Traditionally the residual layer is removed by an oxygen reactive-ion etching (RIE) step. The need for a vacuum environment and dedicated equipment in this step lowers the throughput and increases the cost of the nanoimprinting process. It also prevents the possibility of patterning isolated functional polymers because oxygen RIE destroys the functional materials. In this work, novel nanoimprinting schemes are developed to nondestructively remove the residual layer in thermal nanoimprinting by solvent developing and dewetting. Combined with a transfer-bonding technique, three-dimensional polymer scaffolds are achieved. The techniques developed here eliminate the RIE step in thermal nanoimprinting and are compatible with roller nanoimprinting for large-scale patterning of polymer micro- or nanostructures. The technique also opens up new applications for nanoimprinting in patterning isolated conjugated polymers for organic electronic devices and circuits. PMID:19468173

  4. Aromatic/aliphatic diamine derivatives for advanced compositions and polymers

    NASA Technical Reports Server (NTRS)

    Delozier, Donovan M. (Inventor); Watson, Kent A. (Inventor); Connell, John W. (Inventor); Smith, Jr., Joseph G. (Inventor)

    2010-01-01

    Novel compositions of matter comprise certain derivatives of 9,9-dialkyl fluorene diamine (AFDA). The resultant compositions, whether compositions of matter or monomers that are subsequently incorporated into a polymer, are unique and useful in a variety of applications. Useful applications of AFDA-based material include heavy ion radiation shielding components and components of optical and electronic devices.

  5. Advanced Space Fission Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Borowski, Stanley K.

    2010-01-01

    Fission has been considered for in-space propulsion since the 1940s. Nuclear Thermal Propulsion (NTP) systems underwent extensive development from 1955-1973, completing 20 full power ground tests and achieving specific impulses nearly twice that of the best chemical propulsion systems. Space fission power systems (which may eventually enable Nuclear Electric Propulsion) have been flown in space by both the United States and the Former Soviet Union. Fission is the most developed and understood of the nuclear propulsion options (e.g. fission, fusion, antimatter, etc.), and fission has enjoyed tremendous terrestrial success for nearly 7 decades. Current space nuclear research and technology efforts are focused on devising and developing first generation systems that are safe, reliable and affordable. For propulsion, the focus is on nuclear thermal rockets that build on technologies and systems developed and tested under the Rover/NERVA and related programs from the Apollo era. NTP Affordability is achieved through use of previously developed fuels and materials, modern analytical techniques and test strategies, and development of a small engine for ground and flight technology demonstration. Initial NTP systems will be capable of achieving an Isp of 900 s at a relatively high thrust-to-weight ratio. The development and use of first generation space fission power and propulsion systems will provide new, game changing capabilities for NASA. In addition, development and use of these systems will provide the foundation for developing extremely advanced power and propulsion systems capable of routinely and affordably accessing any point in the solar system. The energy density of fissile fuel (8 x 10(exp 13) Joules/kg) is more than adequate for enabling extensive exploration and utilization of the solar system. For space fission propulsion systems, the key is converting the virtually unlimited energy of fission into thrust at the desired specific impulse and thrust

  6. From Gelation and Glass Transition of Colloidal Systems to Polymers

    NASA Astrophysics Data System (ADS)

    Han, Charles; Yuan, Guangcui; Cheng, He

    Charles C. Han, Guangcui Yuan and He Cheng Joint Laboratory of Polymer Science and Materials, ICCAS, Beijing, China and Institute for Advanced Study, Shenzhen University, Shenzhen, China Aggregation and gelation behavior of mixed suspensions of polystyrene microspheres and poly(N-isopropylacrylamide) microgels have been studied. In dilute microsphere suspensions, with increasing concentration of microgel (MG), microspheres (MS) first aggregated with each other through the bridging of the microgels, then dispersed individually when saturated adsorption was achieved, and finally depletion clusters formed at even higher concentrations of microgel. In concentrated microsphere suspensions, with saturated MG adsorption, a state transition from attractive glass to repulsive glass can be observed. This type of system can be viewed as a molecular model system which has a long range repulsive interaction potential and a short range attractive potential. A comparison between the glass transition of the colloidal systems and the glass transition of polymeric systems can be made.

  7. Rupture dynamics in model polymer systems.

    PubMed

    Borah, Rupam; Debnath, Pallavi

    2016-05-11

    In this paper we explore the rupture dynamics of a model polymer system to capture the microscopic mechanism during relative motion of surfaces at the single polymer level. Our model is similar to the model for friction introduced by Filippov, Klafter, and Urbakh [Filippov et al., Phys. Rev. Lett., 2004, 92, 135503]; but with an important generalization to a flexible transducer (modelled as a bead spring polymer) which is attached to a fixed rigid planar substrate by interconnecting bonds (modelled as harmonic springs), and pulled by a constant force FT. Bonds are allowed to rupture stochastically. The model is simulated, and the results for a certain set of parameters exhibit a sequential rupture mechanism resulting in rupture fronts. A mean field formalism is developed to study these rupture fronts and the possible propagating solutions for the coupled bead and bond dynamics, where the coupling excludes an exact analytical treatment. Numerical solutions to mean field equations are obtained by standard numerical techniques, and they agree well with the simulation results which show sequential rupture. Within a travelling wave formalism based on the Tanh method, we show that the velocity of the rupture front can be obtained in closed form. The derived expression for the rupture front velocity gives good agreement with the stochastic and mean field results, when the rupture is sequential, while propagating solutions for bead and bond dynamics are shown to agree under certain conditions. PMID:27087684

  8. Gas fired Advanced Turbine System

    SciTech Connect

    LeCren, R.T.; White, D.J.

    1993-01-01

    The primary objective of the first phase of the Advanced Gas Turbine System (ATS) program was the concept definition of an advanced engine system that meets efficiency and emission goals far exceeding those that can be provided with today`s equipment. The thermal efficiency goal for such an advanced industrial engine was set at 50% some 15 percentage points higher than current equipment levels. Exhaust emissions goals for oxides of nitrogen (NO{sub x}), carbon monoxide (CO), and unburned hydrocarbons (UH) were fixed at 8 parts per million by volume (ppmv), 20 ppmv, and 20 ppmv respectively, corrected to 15% oxygen (O{sub 2}) levels. Other goals had to be addressed; these involved reducing the cost of power produced by 10 percent and improving or maintaining the reliability, availability, and maintainability (RAM) at current levels. This advanced gas turbine was to be fueled with natural gas, and it had to embody features that would allow it bum coal or coal derived fuels.

  9. Recent advances in metathesis-derived polymers containing transition metals in the side chain.

    PubMed

    Dragutan, Ileana; Dragutan, Valerian; Simionescu, Bogdan C; Demonceau, Albert; Fischer, Helmut

    2015-01-01

    This account critically surveys the field of side-chain transition metal-containing polymers as prepared by controlled living ring-opening metathesis polymerization (ROMP) of the respective metal-incorporating monomers. Ferrocene- and other metallocene-modified polymers, macromolecules including metal-carbonyl complexes, polymers tethering early or late transition metal complexes, etc. are herein discussed. Recent advances in the design and syntheses reported mainly during the last three years are highlighted, with special emphasis on new trends for superior applications of these hybrid materials. PMID:26877797

  10. Recent advances in metathesis-derived polymers containing transition metals in the side chain

    PubMed Central

    Demonceau, Albert; Fischer, Helmut

    2015-01-01

    Summary This account critically surveys the field of side-chain transition metal-containing polymers as prepared by controlled living ring-opening metathesis polymerization (ROMP) of the respective metal-incorporating monomers. Ferrocene- and other metallocene-modified polymers, macromolecules including metal-carbonyl complexes, polymers tethering early or late transition metal complexes, etc. are herein discussed. Recent advances in the design and syntheses reported mainly during the last three years are highlighted, with special emphasis on new trends for superior applications of these hybrid materials. PMID:26877797

  11. Polymer/Graphene Hybrids for Advanced Energy-Conversion and -Storage Materials.

    PubMed

    Cui, Linfan; Gao, Jian; Xu, Tong; Zhao, Yang; Qu, Liangti

    2016-04-20

    Polymer/graphene-based materials with interesting physical and chemical properties have been attracting considerable attention and have been shown to have great potential as active materials in the field of energy conversion and storage. In this review, we focus on recent significant advances in the fabrication and application of polymer/graphene hybrids as electrocatalysts and electrode materials. Synthetic strategies and application of these materials in energy conversion and storage are presented, particularly in devices such as fuel cells, actuators, and supercapacitors, accompanied with a discussion of the challenges and research directions necessary for the future development of polymer/graphene hybrids. PMID:26878997

  12. Advanced flight control system study

    NASA Technical Reports Server (NTRS)

    Hartmann, G. L.; Wall, J. E., Jr.; Rang, E. R.; Lee, H. P.; Schulte, R. W.; Ng, W. K.

    1982-01-01

    A fly by wire flight control system architecture designed for high reliability includes spare sensor and computer elements to permit safe dispatch with failed elements, thereby reducing unscheduled maintenance. A methodology capable of demonstrating that the architecture does achieve the predicted performance characteristics consists of a hierarchy of activities ranging from analytical calculations of system reliability and formal methods of software verification to iron bird testing followed by flight evaluation. Interfacing this architecture to the Lockheed S-3A aircraft for flight test is discussed. This testbed vehicle can be expanded to support flight experiments in advanced aerodynamics, electromechanical actuators, secondary power systems, flight management, new displays, and air traffic control concepts.

  13. Advanced gas turbine systems program

    SciTech Connect

    Zeh, C.M.

    1995-06-01

    The U.S. Department of Energy (DOE) is sponsoring a program to develop fuel-efficient gas turbine-based power systems with low emissions. DOE`s Office of Fossil Energy (DOE/FE) and Office of Energy Efficiency and Renewable Energy (DOE/EE) have initiated an 8-year program to develop high-efficiency, natural gas-fired advanced gas turbine power systems. The Advanced Turbine Systems (ATS) Program will support full-scale prototype demonstration of both industrial- and utility-scale systems that will provide commercial marketplace entries by the year 2000. When the program targets are met, power system emissions will be lower than from the best technology in use today. Efficiency of the utility-scale units will be greater than 60 percent on a lower heating value basis, and emissions of carbon dioxide will be reduced inversely with this increase. Industrial systems will also see an improvement of at least 15 percent in efficiency. Nitrogen oxides will be reduced by at least 10 percent, and carbon monoxide and hydrocarbon emissions will each be kept below 20 parts per million, for both utility and industrial systems.

  14. Research on advanced transportation systems

    NASA Astrophysics Data System (ADS)

    Nagai, Hirokazu; Hashimoto, Ryouhei; Nosaka, Masataka; Koyari, Yukio; Yamada, Yoshio; Noda, Keiichirou; Shinohara, Suetsugu; Itou, Tetsuichi; Etou, Takao; Kaneko, Yutaka

    1992-08-01

    An overview of the researches on advanced space transportation systems is presented. Conceptual study is conducted on fly back boosters with expendable upper stage rocket systems assuming a launch capacity of 30 tons and returning to the launch site by the boosters, and prospect of their feasibility is obtained. Reviews are conducted on subjects as follows: (1) trial production of 10 tons sub scale engines for the purpose of acquiring hardware data and picking up technical problems for full scale 100 tons thrust engines using hydrocarbon fuels; (2) development techniques for advanced liquid propulsion systems from the aspects of development schedule, cost; (3) review of conventional technologies, and common use of component; (4) oxidant switching propulsion systems focusing on feasibility of Liquefied Air Cycle Engine (LACE) and Compressed Air Cycle Engine (CACE); (5) present status of slosh hydrogen manufacturing, storage, and handling; (6) construction of small high speed dynamometer for promoting research on mini pump development; (7) hybrid solid boosters under research all over the world as low-cost and clean propulsion systems; and (8) high performance solid propellant for upper stage and lower stage propulsion systems.

  15. Polymer-based platform for microfluidic systems

    DOEpatents

    Benett, William; Krulevitch, Peter; Maghribi, Mariam; Hamilton, Julie; Rose, Klint; Wang, Amy W.

    2009-10-13

    A method of forming a polymer-based microfluidic system platform using network building blocks selected from a set of interconnectable network building blocks, such as wire, pins, blocks, and interconnects. The selected building blocks are interconnectably assembled and fixedly positioned in precise positions in a mold cavity of a mold frame to construct a three-dimensional model construction of a microfluidic flow path network preferably having meso-scale dimensions. A hardenable liquid, such as poly (dimethylsiloxane) is then introduced into the mold cavity and hardened to form a platform structure as well as to mold the microfluidic flow path network having channels, reservoirs and ports. Pre-fabricated elbows, T's and other joints are used to interconnect various building block elements together. After hardening the liquid the building blocks are removed from the platform structure to make available the channels, cavities and ports within the platform structure. Microdevices may be embedded within the cast polymer-based platform, or bonded to the platform structure subsequent to molding, to create an integrated microfluidic system. In this manner, the new microfluidic platform is versatile and capable of quickly generating prototype systems, and could easily be adapted to a manufacturing setting.

  16. Polymer-based heat exchanger desiccant systems

    SciTech Connect

    Staton, J.C.; Howard, J.L.; Scott, E.P.; Kander, R.G.

    1999-07-01

    The increasing popularity of desiccant-enhanced air conditioning systems has sparked new interest in the search for a better, more efficient desiccant material. The ultimate goal of this research was to develop a material that, when applied to an existing air-to-air heat exchanger, would achieve the necessary heat and mass transfer in a single process, thus transforming a sensible heat exchanger into a total enthalpy exchanger. This study focused on the development and determination of appropriate polymeric desiccant materials for use in different heat and mass transfer systems. The specific objectives for the study were to select an appropriate polymer desiccant, determine the necessary materials properties for this material, and develop and implement mathematical models to analyze the desiccant performance. Two systems were investigated for this study: a rotary wheel total enthalpy exchanger and a fixed plate total enthalpy exchanger. Seven different polymer materials were analyzed to determine the most suitable candidate. Although for the specific conditions studied, the commercial paper-ceramic desiccant out-performed the PVOH materials in both rotary wheel and fixed plate systems, the results suggested that two PVOH materials, PVOH open-cell foam and PVOH/silica gel/molecular sieve composite, have potential for use in total energy exchange applications. By modifying the design conditions, total efficiencies exceeding 70% were achieved for both PVOH foam and PVOH/ceramic composite in rotary wheel systems. In addition, modified the design conditions resulted in total efficiencies greater than 90% for the PVOH foam in both counter-flow and cross-flow flat plate systems. These findings indicated that with appropriate optimization of the exchanger design, these two PVOH materials could have the potential to perform as well as desiccant materials in current rotary wheel and fixed plate exchanger systems.

  17. Advanced Electric Traction System Technology Development

    SciTech Connect

    Anderson, Iver

    2011-01-14

    As a subcontractor to General Motors (GM), Ames Laboratory provided the technical expertise and supplied experimental materials needed to assess the technology of high energy bonded permanent magnets that are injection or compression molded for use in the Advanced Electric Traction System motor. This support was a sustained (Phase 1: 6/07 to 3/08) engineering effort that builds on the research achievements of the primary FreedomCAR project at Ames Laboratory on development of high temperature magnet alloy particulate in both flake and spherical powder forms. Ames Lab also provide guidance and direction in selection of magnet materials and supported the fabrication of experimental magnet materials for development of injection molding and magnetization processes by Arnold Magnetics, another project partner. The work with Arnold Magnetics involved a close collaboration on particulate material design and processing to achieve enhanced particulate properties and magnetic performance in the resulting bonded magnets. The overall project direction was provided by GM Program Management and two design reviews were held at GM-ATC in Torrance, CA. Ames Lab utilized current expertise in magnet powder alloy design and processing, along with on-going research advances being achieved under the existing FreedomCAR Program project to help guide and direct work during Phase 1 for the Advanced Electric Traction System Technology Development Program. The technical tasks included review of previous GM and Arnold Magnets work and identification of improvements to the benchmark magnet material, Magnequench MQP-14-12. Other benchmark characteristics of the desired magnet material include 64% volumetric loading with PPS polymer and a recommended maximum use temperature of 200C. A collaborative relationship was maintained with Arnold Magnets on the specification and processing of the bonded magnet material required by GM-ATC.

  18. Shear-Sensitive Monomer/Polymer Liquid Crystal System

    NASA Technical Reports Server (NTRS)

    Singh, Jag J.; Eftekhari, Abe; Parmar, D. S.

    1993-01-01

    Report describes preliminary investigation of new monomer/polymer liquid crystal system, thin film of shear-sensitive cholesteric monomer liquid crystal (TI 511) on Xydar (STR800) (or equivalent) liquid crystal polymer substrate. Monomer/polymer liquid crystal films applied to surfaces provide quantitative indications of shear stresses caused by winds blowing along surfaces. Effects of shear stresses reversible in new coating system. System provides quantitative data on flows in wind tunnels.

  19. Free Radical Addition Polymerization Kinetics without Steady-State Approximations: A Numerical Analysis for the Polymer, Physical, or Advanced Organic Chemistry Course

    ERIC Educational Resources Information Center

    Iler, H. Darrell; Brown, Amber; Landis, Amanda; Schimke, Greg; Peters, George

    2014-01-01

    A numerical analysis of the free radical addition polymerization system is described that provides those teaching polymer, physical, or advanced organic chemistry courses the opportunity to introduce students to numerical methods in the context of a simple but mathematically stiff chemical kinetic system. Numerical analysis can lead students to an…

  20. Microgravity polymer and crystal growth at the Advanced Materials Center for the Commercial Development of Space

    NASA Technical Reports Server (NTRS)

    Mccauley, Lisa A.

    1990-01-01

    The microgravity research programs currently conducted by the Advanced Materials Center for the Commercial Development of Space (CCDS) are briefly reviewed. Polymer processing in space, which constitutes the most active microgravity program at the Advanced Materials CCDS, is conducted in three areas: membrane processing, multiphase composite behavior, and plasma polymerization. Current work in microgravity crystal growth is discussed with particular reference to the development of the Zeolite Crystal Growth facility.

  1. [New polymer-drug systems based on natural and synthetic polymers].

    PubMed

    Racoviţă, Stefania; Vasiliu, Silvia; Foia, Liliana

    2010-01-01

    The great versatility of polymers makes them very useful in the biomedical and pharmaceutical fields. The combination of natural and synthetic polymers leads to new materials with tailored functional properties. The aim of this work consists in the preparation of new drug delivery system based on chitosan (natural polymer) and polybetaines (synthetic polymers), by a simple process, well known in the literature as complex coacervation methods. Also, the adsorption and release studies of two antibiotics as well as the preservation of their bactericidal capacities were performed. PMID:20700991

  2. NASA Advanced Explorations Systems: Advancements in Life Support Systems

    NASA Technical Reports Server (NTRS)

    Shull, Sarah A.; Schneider, Walter F.

    2016-01-01

    The NASA Advanced Exploration Systems (AES) Life Support Systems (LSS) project strives to develop reliable, energy-efficient, and low-mass spacecraft systems to provide environmental control and life support systems (ECLSS) critical to enabling long duration human missions beyond low Earth orbit (LEO). Highly reliable, closed-loop life support systems are among the capabilities required for the longer duration human space exploration missions assessed by NASA's Habitability Architecture Team (HAT). The LSS project is focused on four areas: architecture and systems engineering for life support systems, environmental monitoring, air revitalization, and wastewater processing and water management. Starting with the international space station (ISS) LSS systems as a point of departure (where applicable), the mission of the LSS project is three-fold: 1. Address discrete LSS technology gaps 2. Improve the reliability of LSS systems 3. Advance LSS systems towards integrated testing on the ISS. This paper summarized the work being done in the four areas listed above to meet these objectives. Details will be given on the following focus areas: Systems Engineering and Architecture- With so many complex systems comprising life support in space, it is important to understand the overall system requirements to define life support system architectures for different space mission classes, ensure that all the components integrate well together and verify that testing is as representative of destination environments as possible. Environmental Monitoring- In an enclosed spacecraft that is constantly operating complex machinery for its own basic functionality as well as science experiments and technology demonstrations, it's possible for the environment to become compromised. While current environmental monitors aboard the ISS will alert crew members and mission control if there is an emergency, long-duration environmental monitoring cannot be done in-orbit as current methodologies

  3. Demonstration Advanced Avionics System (DAAS), Phase 1

    NASA Technical Reports Server (NTRS)

    Bailey, A. J.; Bailey, D. G.; Gaabo, R. J.; Lahn, T. G.; Larson, J. C.; Peterson, E. M.; Schuck, J. W.; Rodgers, D. L.; Wroblewski, K. A.

    1981-01-01

    Demonstration advanced anionics system (DAAS) function description, hardware description, operational evaluation, and failure mode and effects analysis (FMEA) are provided. Projected advanced avionics system (PAAS) description, reliability analysis, cost analysis, maintainability analysis, and modularity analysis are discussed.

  4. Method for separating biological cells. [suspended in aqueous polymer systems

    NASA Technical Reports Server (NTRS)

    Brooks, D. E. (Inventor)

    1980-01-01

    A method for separating biological cells by suspending a mixed cell population in a two-phase polymer system is described. The polymer system consists of droplet phases with different surface potentials for which the cell populations exhibit different affinities. The system is subjected to an electrostatic field of sufficient intensity to cause migration of the droplets with an attendant separation of cells.

  5. Advanced System for Process Engineering

    1992-02-01

    ASPEN (Advanced System for Process Engineering) is a state of the art process simulator and economic evaluation package which was designed for use in engineering fossil energy conversion processes. ASPEN can represent multiphase streams including solids, and handle complex substances such as coal. The system can perform steady state material and energy balances, determine equipment size and cost, and carry out preliminary economic evaluations. It is supported by a comprehensive physical property system for computationmore » of major properties such as enthalpy, entropy, free energy, molar volume, equilibrium ratio, fugacity coefficient, viscosity, thermal conductivity, and diffusion coefficient for specified phase conditions; vapor, liquid, or solid. The properties may be computed for pure components, mixtures, or components in a mixture, as appropriate. The ASPEN Input Language is oriented towards process engineers.« less

  6. Advanced Land Imager Assessment System

    NASA Technical Reports Server (NTRS)

    Chander, Gyanesh; Choate, Mike; Christopherson, Jon; Hollaren, Doug; Morfitt, Ron; Nelson, Jim; Nelson, Shar; Storey, James; Helder, Dennis; Ruggles, Tim; Kaita, Ed; Levy, Raviv; Ong, Lawrence; Markham, Brian; Schweiss, Robert

    2008-01-01

    The Advanced Land Imager Assessment System (ALIAS) supports radiometric and geometric image processing for the Advanced Land Imager (ALI) instrument onboard NASA s Earth Observing-1 (EO-1) satellite. ALIAS consists of two processing subsystems for radiometric and geometric processing of the ALI s multispectral imagery. The radiometric processing subsystem characterizes and corrects, where possible, radiometric qualities including: coherent, impulse; and random noise; signal-to-noise ratios (SNRs); detector operability; gain; bias; saturation levels; striping and banding; and the stability of detector performance. The geometric processing subsystem and analysis capabilities support sensor alignment calibrations, sensor chip assembly (SCA)-to-SCA alignments and band-to-band alignment; and perform geodetic accuracy assessments, modulation transfer function (MTF) characterizations, and image-to-image characterizations. ALIAS also characterizes and corrects band-toband registration, and performs systematic precision and terrain correction of ALI images. This system can geometrically correct, and automatically mosaic, the SCA image strips into a seamless, map-projected image. This system provides a large database, which enables bulk trending for all ALI image data and significant instrument telemetry. Bulk trending consists of two functions: Housekeeping Processing and Bulk Radiometric Processing. The Housekeeping function pulls telemetry and temperature information from the instrument housekeeping files and writes this information to a database for trending. The Bulk Radiometric Processing function writes statistical information from the dark data acquired before and after the Earth imagery and the lamp data to the database for trending. This allows for multi-scene statistical analyses.

  7. Advanced power systems for EOS

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila G.; Weinberg, Irving; Flood, Dennis J.

    1991-01-01

    The Earth Observing System, which is part of the International Mission to Planet Earth, is NASA's main contribution to the Global Change Research Program. Five large platforms are to be launched into polar orbit: two by NASA, two by the European Space Agency, and one by the Japanese. In such an orbit the radiation resistance of indium phosphide solar cells combined with the potential of utilizing 5 micron cell structures yields an increase of 10 percent in the payload capability. If further combined with the Advanced Photovoltaic Solar Array, the total additional payload capability approaches 12 percent.

  8. A wireless system for monitoring polymer encapsulations.

    PubMed

    von Metzen, Rene P; Stieglitz, Thomas

    2007-01-01

    We present a principle for monitoring of the electrical properties of polymers used as insulators for electrically active implants. This method can be used for measurements in vitro and in vivo with incomplex instrumentation. The system is based on the detuning of an oscillating circuit with an interdigital electrode (IDE) structure serving as a capacitive and resistive sensor within the oscillator. This circuit is powered via an inductive link from an external coil. The phase of the external coil's impedance is used to determine the resonance frequency and quality factor of the sensing part wirelessly. The research objective is to obtain detailed information about processes at the metal/polymer interface such as a change of the capacity due to altering of the dielectric constant (i.e. uptake of water vapor or condensation of water) and lowering of the quality factor because of leakage currents. With this information it is possible to detect if the encapsulation is stable, if degradation and loss of adhesion occurs, and if the metal corrodes. The method can be used to evaluate the long term stability of materials and technologies in vitro. The future application is to monitor the stability of implant encapsulations in situ to predict failures before they occur. PMID:18003538

  9. On microstates counting in many body polymer quantum systems

    SciTech Connect

    Chacon-Acosta, Guillermo; Morales-Tecotl, Hugo A.; Dagdug, Leonardo

    2011-10-14

    Polymer quantum systems are mechanical models quantized in a similar way as loop quantum gravity but in which loops/graphs resembling polymers are replaced by discrete sets of points. Such systems have allowed to study in a simpler context some novel aspects of loop quantum gravity. Although thermal aspects play a crucial role in cosmology and black hole physics little attention has been given to the thermostatistics of many body polymer quantum systems. In this work we explore how the features of a one-dimensional effective polymer gas, affect its microstate counting and hence the corresponding thermodynamical quantities.

  10. Advanced High Temperature Polymer Matrix Composites for Gas Turbine Engines Program Expansion

    NASA Technical Reports Server (NTRS)

    Hanley, David; Carella, John

    1999-01-01

    This document, submitted by AlliedSignal Engines (AE), a division of AlliedSignal Aerospace Company, presents the program final report for the Advanced High Temperature Polymer Matrix Composites for Gas Turbine Engines Program Expansion in compliance with data requirements in the statement of work, Contract No. NAS3-97003. This document includes: 1 -Technical Summary: a) Component Design, b) Manufacturing Process Selection, c) Vendor Selection, and d) Testing Validation: 2-Program Conclusion and Perspective. Also, see the Appendix at the back of this report. This report covers the program accomplishments from December 1, 1996, to August 24, 1998. The Advanced High Temperature PMC's for Gas Turbine Engines Program Expansion was a one year long, five task technical effort aimed at designing, fabricating and testing a turbine engine component using NASA's high temperature resin system AMB-21. The fiber material chosen was graphite T650-35, 3K, 8HS with UC-309 sizing. The first four tasks included component design and manufacturing, process selection, vendor selection, component fabrication and validation testing. The final task involved monthly financial and technical reports.

  11. Advanced Docking Berthing System Update

    NASA Technical Reports Server (NTRS)

    Lewis, James

    2006-01-01

    In FY05 the Exploration Systems Technology Maturation Program selected the JSC advanced mating systems development to continue as an in-house project. In FY06, as a result of ESAS Study (60 Day Study) the CEV Project (within the Constellation Program) has chosen to continue the project as a GFE Flight Hardware development effort. New requirement for CEV to travel and dock with the ISS in 2011/12 in support of retiring the Shuttle and reducing the gap of time where US does not have any US based crew launch capability. As before, long-duration compatible seal-on-seal technology (seal-on-seal to support androgynous interface) has been identified as a risk mitigation item.

  12. Mechanical properties of hybrid polymer nanotube systems

    NASA Astrophysics Data System (ADS)

    Coleman, Jonathan N.; Cadek, Martin; Dalton, Alan B.; Munoz, Edgar; Razal, Joselito; Baughman, Ray H.; Blau, Werner J.

    2003-04-01

    In this work, mechanical properties of hybrid materials fabricated from nanotubes and commercially available polymers were investigated. It was found that, by adding various concentrations of arc discharge multiwall nanotubes, both Young"s modulus and hardness increased by factors of 1.8 and 1.6 at 1wt% in PVA and 2.8 and 2.0 at 8wt% in PVK, in reasonable agreement with the Halpin-Tsai theory. Furthermore, the presence of the nanotubes was found to nucleate crystallization of the PVA. This crystal growth is thought to enhance matrix-nanotube stress transfer. In addition, microscopy studies suggest extremely strong interfacial bonding in the PVA-based composite. This is manifested by the fracture of the polymer rather that the polymer-nanotube interface. The dependence of the polymer nanotube interfacial interaction on host polymer was studied by intercalating various polymers (PVA, PVP and PS) into single wall nanotube buckypaper. Even for short soak times, significant polymer intercalation into existing free volume was observed. Depending on the polymer and the level of intercalation tensile tests on intercalated sheets showed that the Young"s modulus, strength and toughness increased by factors of 3, 9 and 28, respectively. This indicates that the intercalated polymer enhances load transmission between nanotubes due the significant stress transfer. The level of stress transfer was observed to scale with polymer hydrophobicity as expected.

  13. Recent Advances in Targeted Drug Delivery Approaches Using Dendritic Polymers

    PubMed Central

    Bugno, Jason; Hsu, Hao-Jui; Hong, Seungpyo

    2014-01-01

    Since they were first synthesized over 30 years ago, dendrimers have seen rapid translation into various biomedical applications. A number of reports have not only demonstrated their clinical utility, but also revealed novel design approaches and strategies based on the elucidation of underlying mechanisms governing their biological interactions. This review focuses on presenting the latest advances in dendrimer design, discussing the current mechanistic understandings, and highlighting recent developments and targeted approaches using dendrimers in drug/gene delivery. PMID:26221937

  14. Cell partition in two phase polymer systems

    NASA Technical Reports Server (NTRS)

    Brooks, D. E.

    1979-01-01

    Aqueous phase-separated polymer solutions can be used as support media for the partition of biological macromolecules, organelles and cells. Cell separations using the technique have proven to be extremely sensitive to cell surface properties but application of the systems are limited to cells or aggregates which do not significantly while the phases are settling. Partition in zero g in principle removes this limitation but an external driving force must be applied to induce the phases to separate since their density difference disappears. We have recently shown that an applied electric field can supply the necessary driving force. We are proposing to utilize the NASA FES to study field-driven phase separation and cell partition on the ground and in zero g to help define the separation/partition process, with the ultimate goal being to develop partition as a zero g cell separation technique.

  15. Polymer optical fiber sensors for civil infrastructure systems

    NASA Astrophysics Data System (ADS)

    Kiesel, Sharon; Peters, Kara; Abdi, O.; Hassan, Tasnim; Kowalsky, Mervyn

    2007-04-01

    This paper presents intrinsic polymer fiber (POF) sensors for high-strain applications such as the performance-based assessment and health monitoring of civil infrastructure systems subjected to earthquake loading or morphing aircraft. POFs provide a potential maximum strain range of 6-12%, are more flexible that silica optical fibers, and are more durable in harsh chemical or environmental conditions. Recent advances in the fabrication of singlemode POFs have made it possible to extend POFs to interferometric sensor capabilities. Furthermore, the interferometric nature of intrinsic sensors permits high accuracy for such measurements. Measurements of the mechanical response of the sensor at various strain rates are presented. In addition, the design of a time-of-flight interferometer for phase measurements over the large strain range required is discussed. Finally the bond strength between the embedded POF and various structural materials is investigated and a methodology demonstrated for embedment of the sensors into a reinforced concrete structural component.

  16. Advances with polymer-free amphilimus-eluting stents.

    PubMed

    CARRIé, Didier

    2016-06-01

    Despite the improved clinical outcomes following the availability of second generation drug eluting stents (DES), percutaneous coronary intervention (PCI) is associated with worse clinical and angiographic outcomes among the patients with diabetes mellitus (DM) than among non-diabetics. The Cre8 Amphilimus-eluting DES is polymer-free, resulting in a reduced inflammatory response and lower risk of stent thrombosis. In a clinical study, it showed equivalent efficacy and safety in diabetic and non-diabetic populations, a unique finding among DES studies. These findings were confirmed in a real-world study, Investig8, and another real-world study, Particip8, is ongoing. The RESERVOIR Clinical Trial recruited patients with DM and showed noninferiority of the Cre8 DES compared to an everolimus eluting DES (EES) in the overall group but showed a statistical superiority of Cre8 in diabetic patients with higher metabolic dysfunctions. The Cre8 DES is therefore a valuable option for this important patient population. PMID:26934663

  17. Advances in ferroelectric polymers for shock compression sensors

    SciTech Connect

    Bauer, F.; Moulard, H.; Samara, G.

    1997-10-01

    Our studies of the shock compression response of PVDF polymer are continuing in order to understand the physical properties under shock loading and to develop high fidelity, reproducible, time-resolved dynamic stress gauges. New PVDF technology, new electrode configurations and piezoelectric analysis have resulted in enhanced precision gauges. Our new standard gauges have a precision of better than 1% in electric charge release under shock up to 15 GPa. The piezoelectric response of shock compressed PVDF gauges 1 mm{sup 2} in active area has been studied and yielded well-behaved reproducible data up to 20 GPa. Analysis of the response of these gauges in the {open_quotes}thin mode regime{close_quotes} using a Lagrangian hydrocode will be presented. P(VDF-TrFE) copolymers exhibit unique piezoelectric properties over a wide range of temperature depending on the composition. Their properties and phase transitions are being investigated. Emphasis of the presentation will be on key results and implications.

  18. Advances on Magnetic Nanocarriers Based on Natural Polymers.

    PubMed

    Muzzalupo, Rita; Tavano, Lorena

    2016-01-01

    The use of nanodevices to transport active compounds like small-molecular drugs, peptides, or genes found an increased attention throughout the different fields of natural sciences. Moreover, recent research trends are focused on the employment of smart nanocarriers able to react on certain internal or external applied stimuli, in order to achieve temporal and site-specific drugs/gene release. In contrast to traditional biodegradable nanocarriers that slowly release drugs inside the cells, these smart nanosystems are able to quickly release or even dump drugs in response to a specific biological signal in the target cancer cells such lower pH, high redox potential or over expression of enzymes or to external stimuli such as temperature, light, ultrasounds and magnetic field. This review gives a brief overview about some types of stimuli-responsive nanocarriers, with the main focus on magnetic fieldresponsive devices obtained from natural polymers. The concept of magnetic field-sensitive nanocarriers, their advantages and disadvantages, the methods of preparation and applications in various fields of drug delivery will be explored, giving an exhaustive collection of the findings of recent investigations. PMID:26861649

  19. Advances in ferroelectric polymers for shock compression sensors

    SciTech Connect

    Bauer, F.; Moulard, H.; Samara, G.

    1998-07-01

    Our studies of the shock compression response of PVDF polymer are continuing in order to understand the physical properties under shock loading and to develop high fidelity, reproducible, time-resolved dynamic stress gauges. New PVDF technology, new electrode configurations and piezoelectric analysis have resulted in enhanced precision gauges. Our new standard gauges have a precision of better than 1{percent} in electrical charge release under shock up to 15 GPa. The piezoelectric response of shock compressed PVDF gauges 1 mm{sup 2} in active area has been studied and yielded well-behaved reproducible data up to 20 GPa. Analysis of the response of these gauges in the {open_quotes}thin mode regime{close_quotes} using a Lagrangian hydrocode will be presented. P(VDF-TrFE) copolymers exhibit unique piezoelectric properties over a wide range of temperature depending on the composition. Their properties and phase transitions are being investigated. Emphasis of the presentation will be on key results and implications. {copyright} {ital 1998 American Institute of Physics.}

  20. Advanced Space Surface Systems Operations

    NASA Technical Reports Server (NTRS)

    Huffaker, Zachary Lynn; Mueller, Robert P.

    2014-01-01

    The importance of advanced surface systems is becoming increasingly relevant in the modern age of space technology. Specifically, projects pursued by the Granular Mechanics and Regolith Operations (GMRO) Lab are unparalleled in the field of planetary resourcefulness. This internship opportunity involved projects that support properly utilizing natural resources from other celestial bodies. Beginning with the tele-robotic workstation, mechanical upgrades were necessary to consider for specific portions of the workstation consoles and successfully designed in concept. This would provide more means for innovation and creativity concerning advanced robotic operations. Project RASSOR is a regolith excavator robot whose primary objective is to mine, store, and dump regolith efficiently on other planetary surfaces. Mechanical adjustments were made to improve this robot's functionality, although there were some minor system changes left to perform before the opportunity ended. On the topic of excavator robots, the notes taken by the GMRO staff during the 2013 and 2014 Robotic Mining Competitions were effectively organized and analyzed for logistical purposes. Lessons learned from these annual competitions at Kennedy Space Center are greatly influential to the GMRO engineers and roboticists. Another project that GMRO staff support is Project Morpheus. Support for this project included successfully producing mathematical models of the eroded landing pad surface for the vertical testbed vehicle to predict a timeline for pad reparation. And finally, the last project this opportunity made contribution to was Project Neo, a project exterior to GMRO Lab projects, which focuses on rocket propulsion systems. Additions were successfully installed to the support structure of an original vertical testbed rocket engine, thus making progress towards futuristic test firings in which data will be analyzed by students affiliated with Rocket University. Each project will be explained in

  1. A survey of advanced battery systems for space applications

    NASA Technical Reports Server (NTRS)

    Attia, Alan I.

    1989-01-01

    The results of a survey on advanced secondary battery systems for space applications are presented. The objectives were: to identify advanced battery systems capable of meeting the requirements of various types of space missions, with significant advantages over currently available batteries, to obtain an accurate estimate of the anticipated improvements of these advanced systems, and to obtain a consensus for the selection of systems most likely to yield the desired improvements. Few advanced systems are likely to exceed a specific energy of 150 Wh/kg and meet the additional requirements of safety and reliability within the next 15 years. The few that have this potential are: (1) regenerative fuel cells, both alkaline and solid polymer electrolyte (SPE) types for large power systems; (2) lithium-intercalatable cathodes, particularly the metal ozides intercalatable cathodes (MnO2 or CoO2), with applications limited to small spacecrafts requiring limited cycle life and low power levels; (3) lithium molten salt systems (e.g., LiAl-FeS2); and (4) Na/beta Alumina/Sulfur or metal chlorides cells. Likely technological advances that would enhance the performance of all the above systems are also identified, in particular: improved bifunctional oxygen electrodes; improved manufacturing technology for thin film lithium electrodes in combination with polymeric electrolytes; improved seals for the lithium molten salt cells; and improved ceramics for sodium/solid electrolyte cells.

  2. Graphite/Polyimide Composites. [conference on Composites for Advanced Space Transportation Systems

    NASA Technical Reports Server (NTRS)

    Dexter, H. B. (Editor); Davis, J. G., Jr. (Editor)

    1979-01-01

    Technology developed under the Composites for Advanced Space Transportation System Project is reported. Specific topics covered include fabrication, adhesives, test methods, structural integrity, design and analysis, advanced technology developments, high temperature polymer research, and the state of the art of graphite/polyimide composites.

  3. Advanced fiber/matrix material systems

    NASA Technical Reports Server (NTRS)

    Hartness, J. Timothy

    1991-01-01

    Work completed in Phase 1 of the NASA Advanced Composite Technology program is discussed. Two towpreg forms (commingled yarns and fused powder towpregs) are being characterized under the program. These towpregs will be used to evaluate textile fabrication technologies for advanced aircraft composite structures. The unique characteristic of both of these material forms is that both fiber and matrix resin are handled in a single operation such as weaving, braiding, or fiber placement. The evaluation of both commingled and fused powder towpreg is described. Various polymer materials are considered for both subsonic and supersonic applications. Polymers initially being evaluated include thermoplastic polyimides such as Larc-TPI and New-TPI, thermoplastics such as PEEK and PEKEKK as well as some toughened crosslinked polyimides. Preliminary mechanical properties as well as tow handling are evaluated.

  4. Structural health monitoring system/method using electroactive polymer fibers

    NASA Technical Reports Server (NTRS)

    Scott-Carnell, Lisa A. (Inventor); Siochi, Emilie J. (Inventor)

    2013-01-01

    A method for monitoring the structural health of a structure of interest by coupling one or more electroactive polymer fibers to the structure and monitoring the electroactive responses of the polymer fiber(s). Load changes that are experienced by the structure cause changes in the baseline responses of the polymer fiber(s). A system for monitoring the structural health of the structure is also provided.

  5. OPTIMIZATION OF ADVANCED FILTER SYSTEMS

    SciTech Connect

    R.A. Newby; M.A. Alvin; G.J. Bruck; T.E. Lippert; E.E. Smeltzer; M.E. Stampahar

    2002-06-30

    Two advanced, hot gas, barrier filter system concepts have been proposed by the Siemens Westinghouse Power Corporation to improve the reliability and availability of barrier filter systems in applications such as PFBC and IGCC power generation. The two hot gas, barrier filter system concepts, the inverted candle filter system and the sheet filter system, were the focus of bench-scale testing, data evaluations, and commercial cost evaluations to assess their feasibility as viable barrier filter systems. The program results show that the inverted candle filter system has high potential to be a highly reliable, commercially successful, hot gas, barrier filter system. Some types of thin-walled, standard candle filter elements can be used directly as inverted candle filter elements, and the development of a new type of filter element is not a requirement of this technology. Six types of inverted candle filter elements were procured and assessed in the program in cold flow and high-temperature test campaigns. The thin-walled McDermott 610 CFCC inverted candle filter elements, and the thin-walled Pall iron aluminide inverted candle filter elements are the best candidates for demonstration of the technology. Although the capital cost of the inverted candle filter system is estimated to range from about 0 to 15% greater than the capital cost of the standard candle filter system, the operating cost and life-cycle cost of the inverted candle filter system is expected to be superior to that of the standard candle filter system. Improved hot gas, barrier filter system availability will result in improved overall power plant economics. The inverted candle filter system is recommended for continued development through larger-scale testing in a coal-fueled test facility, and inverted candle containment equipment has been fabricated and shipped to a gasifier development site for potential future testing. Two types of sheet filter elements were procured and assessed in the program

  6. Advanced integrated solvent extraction systems

    SciTech Connect

    Horwitz, E.P.; Dietz, M.L.; Leonard, R.A.

    1997-10-01

    Advanced integrated solvent extraction systems are a series of novel solvent extraction (SX) processes that will remove and recover all of the major radioisotopes from acidic-dissolved sludge or other acidic high-level wastes. The major focus of this effort during the last 2 years has been the development of a combined cesium-strontium extraction/recovery process, the Combined CSEX-SREX Process. The Combined CSEX-SREX Process relies on a mixture of a strontium-selective macrocyclic polyether and a novel cesium-selective extractant based on dibenzo 18-crown-6. The process offers several potential advantages over possible alternatives in a chemical processing scheme for high-level waste treatment. First, if the process is applied as the first step in chemical pretreatment, the radiation level for all subsequent processing steps (e.g., transuranic extraction/recovery, or TRUEX) will be significantly reduced. Thus, less costly shielding would be required. The second advantage of the Combined CSEX-SREX Process is that the recovered Cs-Sr fraction is non-transuranic, and therefore will decay to low-level waste after only a few hundred years. Finally, combining individual processes into a single process will reduce the amount of equipment required to pretreat the waste and therefore reduce the size and cost of the waste processing facility. In an ongoing collaboration with Lockheed Martin Idaho Technology Company (LMITCO), the authors have successfully tested various segments of the Advanced Integrated Solvent Extraction Systems. Eichrom Industries, Inc. (Darien, IL) synthesizes and markets the Sr extractant and can supply the Cs extractant on a limited basis. Plans are under way to perform a test of the Combined CSEX-SREX Process with real waste at LMITCO in the near future.

  7. Westinghouse Advanced Particle Filter System

    SciTech Connect

    Lippert, T.E.; Bruck, G.J.; Sanjana, Z.N.; Newby, R.A.; Bachovchin, D.M.

    1996-12-31

    Integrated Gasification Combined Cycles (IGCC) and Pressurized Fluidized Bed Combustion (PFBC) are being developed and demonstrated for commercial, power generation application. Hot gas particulate filters are key components for the successful implementation of IGCC and PFBC in power generation gas turbine cycles. The objective of this work is to develop and qualify through analysis and testing a practical hot gas ceramic barrier filter system that meets the performance and operational requirements of PFBC and IGCC systems. This paper reports on the development and status of testing of the Westinghouse Advanced Hot Gas Particle Filter (W-APF) including: W-APF integrated operation with the American Electric Power, 70 MW PFBC clean coal facility--approximately 6000 test hours completed; approximately 2500 hours of testing at the Hans Ahlstrom 10 MW PCFB facility located in Karhula, Finland; over 700 hours of operation at the Foster Wheeler 2 MW 2nd generation PFBC facility located in Livingston, New Jersey; status of Westinghouse HGF supply for the DOE Southern Company Services Power System Development Facility (PSDF) located in Wilsonville, Alabama; the status of the Westinghouse development and testing of HGF`s for Biomass Power Generation; and the status of the design and supply of the HGF unit for the 95 MW Pinon Pine IGCC Clean Coal Demonstration.

  8. Advanced System for Process Engineering

    1998-09-14

    PRO ASPEN/PC1.0 (Advanced System for Process Engineering) is a state of the art process simulator and economic evaluation package which was designed for use in engineering fossil energy conversion processes and has been ported to run on a PC. PRO ASPEN/PC1.0 can represent multiphase streams including solids, and handle complex substances such as coal. The system can perform steady state material and energy balances, determine equipment size and cost, and carry out preliminary economic evaluations.more » It is supported by a comprehensive physical property system for computation of major properties such as enthalpy, entropy, free energy, molar volume, equilibrium ratio, fugacity coefficient, viscosity, thermal conductivity, and diffusion coefficient for specified phase conditions; vapor, liquid, or solid. The properties may be computed for pure components, mixtures, or components in a mixture, as appropriate. The PRO ASPEN/PC1.0 Input Language is oriented towards process engineers.« less

  9. A Processable Shape Memory Polymer System for Biomedical Applications.

    PubMed

    Hearon, Keith; Wierzbicki, Mark A; Nash, Landon D; Landsman, Todd L; Laramy, Christine; Lonnecker, Alexander T; Gibbons, Michael C; Ur, Sarah; Cardinal, Kristen O; Wilson, Thomas S; Wooley, Karen L; Maitland, Duncan J

    2015-06-24

    Polyurethane shape memory polymers (SMPs) with tunable thermomechanical properties and advanced processing capabilities are synthesized, characterized, and implemented in the design of a microactuator medical device prototype. The ability to manipulate glass transition temperature (Tg ) and crosslink density in low-molecular weight aliphatic thermoplastic polyurethane SMPs is demonstrated using a synthetic approach that employs UV catalyzed thiol-ene "click" reactions to achieve postpolymerization crosslinking. Polyurethanes containing varying C=C functionalization are synthesized, solution blended with polythiol crosslinking agents and photoinitiator and subjected to UV irradiation, and the effects of number of synthetic parameters on crosslink density are reported. Thermomechanical properties are highly tunable, including glass transitions tailorable between 30 and 105 °C and rubbery moduli tailorable between 0.4 and 20 MPa. This new SMP system exhibits high toughness for many formulations, especially in the case of low crosslink density materials, for which toughness exceeds 90 MJ m(-3) at select straining temperatures. To demonstrate the advanced processing capability and synthetic versatility of this new SMP system, a laser-actuated SMP microgripper device for minimally invasive delivery of endovascular devices is fabricated, shown to exhibit an average gripping force of 1.43 ± 0.37 N and successfully deployed in an in vitro experimental setup under simulated physiological conditions. PMID:25925212

  10. Advanced information processing system: Local system services

    NASA Technical Reports Server (NTRS)

    Burkhardt, Laura; Alger, Linda; Whittredge, Roy; Stasiowski, Peter

    1989-01-01

    The Advanced Information Processing System (AIPS) is a multi-computer architecture composed of hardware and software building blocks that can be configured to meet a broad range of application requirements. The hardware building blocks are fault-tolerant, general-purpose computers, fault-and damage-tolerant networks (both computer and input/output), and interfaces between the networks and the computers. The software building blocks are the major software functions: local system services, input/output, system services, inter-computer system services, and the system manager. The foundation of the local system services is an operating system with the functions required for a traditional real-time multi-tasking computer, such as task scheduling, inter-task communication, memory management, interrupt handling, and time maintenance. Resting on this foundation are the redundancy management functions necessary in a redundant computer and the status reporting functions required for an operator interface. The functional requirements, functional design and detailed specifications for all the local system services are documented.

  11. Recovery system containing lanthanide-crosslinked polymers

    SciTech Connect

    Dovan, H.T.; Hutchins, R.D.

    1993-07-13

    A recovery system is described comprising: (a) a subterranean formation; (b) a well bore penetrating at least a portion of the subterranean formation; and (c) a composition capable of forming a gel present in at least a portion of the well bore, wherein the composition comprises: (i) a crosslinkable polymer (CP) selected from the group consisting of heteropolysaccharides obtained by the fermentation of starch-derived sugar, ammonium salts, and alkali metal salts; (ii) a lanthanide; and (iii) an ingredient selected from the group consisting of gel breakers, sequestering agents, proppants for use in hydraulically fracturing, particulate agents for forming a gravel pack, and base precursors selected from the group consisting of ammonium slats, urea, thiourea, and mixtures of these. A second recovery system is described in which the gel composition comprises: (i) a CP selected from the group consisting of acrylic acid-acrylamide copolymers, acrylic acid-methacrylamide copolymers, polyacrylamides, polymethacrylamides, partially hydrolyzed polyacrylamides, partially hydrolyzed polymethacrylamides, polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, polyalkyleneoxides, lignosulfonates, ammonium salts, alkali metal salts, and alkaline earth salts of lignosulfonates; and (ii) a crosslinking agent selected from the group consisting of lanthanides, sequestered lanthanides, and mixtures thereof. A third system is described in which the gel composition comprises: (i) a CP, hydroxyethylcellulose; and (ii) a crosslinking agent selected from the group consisting of lanthanides, sequestered lanthanides, and mixtures thereof. A fourth system is described in which the gel composition comprises: (i) a CP selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, polyalkyleneoxides, lignosulfonates, ammonium salts, alkali metal salts, and alkaline earth salts of lignosulfonates; and (ii) a lanthanide.

  12. Recent Advances in Thermoplastic Puncture-Healing Polymers

    NASA Technical Reports Server (NTRS)

    Bogert, Philip B.; Working, Dennis C.; Wise, Kristopher E.; Smith, Janice Y.; Topping, Crystal C.; Britton, Sean M.; Bagby, Paul R.; Siochi, Emilie J.

    2010-01-01

    The motivation for this work is to develop self-healing polymeric materials to enable damage tolerant systems, and to tailor puncture healing for use temperatures and applications. This will be a benefit in environments and conditions where access for manual repair is limited or impossible, or where damage may not be detected.

  13. Phase behavior of semiflexible polymer systems

    NASA Astrophysics Data System (ADS)

    Moonay, David Jordan

    Phase behavior of semiflexible poly(n-hexyl isocyanate) (PHIC) and flexible coil poly(cyclohexyl methacrylate) (PCHMA) were investigated. Room-temperature solubility screenings showed that PCHMA behavior in various solvents agreed with that predicted by Flory-Huggins theory: solvents had interaction parameter values chi1 < 0.5, i.e., less than the critical value for incipient phase separation, while nonsolvents had chi1 > 1, well within the thermodynamically-poor solvency region. PHIC, on the other hand, had interactions which were not in accord with the simple enthalpic theory. A high-boiling solvent, 1-chloronaphthalene, was chosen as suitable for binary and ternary phase behavior work, as a result of the screenings. PCHMA was found to be soluble at all concentrations at room temperature. However, PHIC crystallized at about 5 wt.% a result not previously reported in the literature. The crystallinity, and degradation, interfered with liquid crystalline expression up to the PHIC melting point in binary solution. The novel room-temperature ternary phase diagram, PHIC/PCHMA/CLN, was developed. Particularly striking is its 5 wt.% total polymer solubility limit, which extended to 90:1 (w/w) ratios of PCHMA:PI-HC in CLN, as verified by serial dilution experiments. Novel gels were prepared with PHIC longer-pendant-group homologs poly(n-nonylisocyanate) and poly(n-undecylisocyanate), to investigate their heightened solubility relative to PHIC, in high-boiling alkylaromatic solvents. Apparently homogeneous isotropic gels in two structurally similar solvents, were found. Lengthening pendant groups in the alkyl isocyanate polymers increases solubility in high-boiling solvents, although gelation occurs when the solutions are cooled to room temperature. Elongational flow apparati were constructed. Trumpet-shaped tube experiments indicated no flow-induced crystallinity of isotropic PHIC/CLN solutions. A planar-elongational flow system was constructed and tested, and its central

  14. Advances in Solar Heating and Cooling Systems

    ERIC Educational Resources Information Center

    Ward, Dan S.

    1976-01-01

    Reports on technological advancements in the fields of solar collectors, thermal storage systems, and solar heating and cooling systems. Diagrams aid in the understanding of the thermodynamics of the systems. (CP)

  15. Advanced optical manufacturing digital integrated system

    NASA Astrophysics Data System (ADS)

    Tao, Yizheng; Li, Xinglan; Li, Wei; Tang, Dingyong

    2012-10-01

    It is necessarily to adapt development of advanced optical manufacturing technology with modern science technology development. To solved these problems which low of ration, ratio of finished product, repetition, consistent in big size and high precision in advanced optical component manufacturing. Applied business driven and method of Rational Unified Process, this paper has researched advanced optical manufacturing process flow, requirement of Advanced Optical Manufacturing integrated System, and put forward architecture and key technology of it. Designed Optical component core and Manufacturing process driven of Advanced Optical Manufacturing Digital Integrated System. the result displayed effective well, realized dynamic planning Manufacturing process, information integration improved ratio of production manufactory.

  16. Polypyrrole composite electrodes in an all-polymer battery system

    SciTech Connect

    Killian, J.G.; Coffey, B.M.; Gao, F.; Poehler, T.O.; Searson, P.C.

    1996-03-01

    The authors have fabricated an all-polymer battery utilizing the redox properties of electrically conducting polymers for the anode and cathode in conjunction with an ionic conducting polymer gel electrolyte. The anode and cathode consist of pyrrole electropolymerized onto a graphite fiber substrate resulting in a high-surface-area, composite electrode. A polymer gel electrolyte, based on polyacrylonitrile, was solution cast onto the electrodes to form an all-polymer cell. This system exhibits a specific charge capacity of 22 mAh/g based on the electroactive mass of the cathode and discharging the system to 0.4 V. These cells show no loss of capacity when cycled to 100 cycles.

  17. Advances in solid polymer electrolyte fuel cell technology with low-platinum-loading electrodes

    NASA Technical Reports Server (NTRS)

    Srinivasan, Supramaniam; Ticianelli, E. A.; Derouin, C. R.; Redondo, A.

    1987-01-01

    The Gemini Space program demonstrated the first major application of fuel cell systems. Solid polymer electrolyte fuel cells were used as auxiliary power sources in the spacecraft. There has been considerable progress in this technology since then, particularly with the substitution of Nafion for the polystyrene sulfonate membrane as the electrolyte. Until recently the performance was good only with high platinum loading (4 mg/sq cm) electrodes. Methods are presented to advance the technology by (1) use of low platinum loading (0.35 mg/sq cm) electrodes; (2) optimization of anode/membrane/cathode interfaces by hot pressing; (3) pressurization of reactant gases, which is most important when air is used as cathodic reactant; and (4) adequate humidification of reactant gases to overcome the water management problem. The high performance of the fuel cell with the low loading of platinum appears to be due to the extension of the three dimensional reaction zone by introduction of a proton conductor, Nafion. This was confirmed by cyclic voltammetry.

  18. 75 FR 53277 - Notice of Workshop on Polymers for Photovoltaic Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... National Institute of Standards and Technology Notice of Workshop on Polymers for Photovoltaic Systems.... SUMMARY: The National Institute of Standards and Technology announces a ] Workshop on Polymers for... polymeric materials used in photovoltaic systems; testing, performance, and reliability of polymers...

  19. Recent advances in solid polymer electrolyte fuel cell technology with low platinum loading electrodes

    NASA Technical Reports Server (NTRS)

    Srinivasan, Supramaniam; Manko, David J.; Enayatullah, Mohammad; Appleby, A. John

    1989-01-01

    High power density fuel cell systems for defense and civilian applications are being developed. Taking into consideration the main causes for efficiency losses (activation, mass transport and ohmic overpotentials) the only fuel cell systems capable of achieving high power densities are the ones with alkaline and solid polymer electrolyte. High power densities (0.8 W/sq cm at 0.8 V and 1 A/sq cm with H2 and O2 as reactants), were already used in NASA's Apollo and Space Shuttle flights as auxiliary power sources. Even higher power densities (4 W/sq cm - i.e., 8 A sq cm at 0.5 V) were reported by the USAF/International Fuel Cells in advanced versions of the alkaline system. High power densities (approximately 1 watt/sq cm) in solid polymer electrolyte fuel cells with ten times lower platinum loading in the electrodes (i.e., 0.4 mg/sq cm) were attained. It is now possible to reach a cell potential of 0.620 V at a current density of 2 A/sq cm and at a temperature of 95 C and pressure of 4/5 atm with H2/O2 as reactants. The slope of the linear region of the potential-current density plot for this case is 0.15 ohm-sq cm. With H2/air as reactants and under the same operating conditions, mass transport limitations are encountered at current densities above 1.4 A/sq cm. Thus, the cell potential at 1 A/sq cm with H2/air as reactants is less than that with H2/O2 as reactants by 40 mV, which is the expected value based on electrode kinetics of the oxygen reduction reaction, and at 2 A/sq cm with H2/air as reactant is less than the corresponding value with H2/O2 as reactants by 250 mV, which is due to the considerably greater mass transport limitations in the former case.

  20. Constitutive Modeling of Nanotube-Reinforced Polymer Composite Systems

    NASA Technical Reports Server (NTRS)

    Odegard, Gregory M.; Harik, Vasyl M.; Wise, Kristopher E.; Gates, Thomas S.

    2001-01-01

    In this study, a technique has been proposed for developing constitutive models for polymer composite systems reinforced with single-walled carbon nanotubes (SWNT). Since the polymer molecules are on the same size scale as the nanotubes, the interaction at the polymer/nanotube interface is highly dependent on the local molecular structure and bonding. At these small length scales, the lattice structures of the nanotube and polymer chains cannot be considered continuous, and the bulk mechanical properties of the SWNT/polymer composites can no longer be determined through traditional micromechanical approaches that are formulated using continuum mechanics. It is proposed herein that the nanotube, the local polymer near the nanotube, and the nanotube/polymer interface can be modeled as an effective continuum fiber using an equivalent-continuum modeling method. The effective fiber retains the local molecular structure and bonding information and serves as a means for incorporating micromechanical analyses for the prediction of bulk mechanical properties of SWNT/polymer composites with various nanotube sizes and orientations. As an example, the proposed approach is used for the constitutive modeling of two SWNT/polyethylene composite systems, one with continuous and aligned SWNT and the other with discontinuous and randomly aligned nanotubes.

  1. Constitutive Modeling of Nanotube-Reinforced Polymer Composite Systems

    NASA Technical Reports Server (NTRS)

    Odegard, Gregory M.; Harik, Vasyl M.; Wise, Kristopher E.; Gates, Thomas S.

    2004-01-01

    In this study, a technique has been proposed for developing constitutive models for polymer composite systems reinforced with single-walled carbon nanotubes (SWNT). Since the polymer molecules are on the same size scale as the nanotubes, the interaction at the polymer/nanotube interface is highly dependent on the local molecular structure and bonding. At these small length scales, the lattice structures of the nanotube and polymer chains cannot be considered continuous, and the bulk mechanical properties of the SWNT/polymer composites can no longer be determined through traditional micromechanical approaches that are formulated using continuum mechanics. It is proposed herein that the nanotube, the local polymer near the nanotube, and the nanotube/polymer interface can be modeled as an effective continuum fiber using an equivalent-continuum modeling method. The effective fiber retains the local molecular structure and bonding information and serves as a means for incorporating micromechanical analyses for the prediction of bulk mechanical properties of SWNT/polymer composites with various nanotube sizes and orientations. As an example, the proposed approach is used for the constitutive modeling of two SWNT/polyethylene composite systems, one with continuous and aligned SWNT and the other with discontinuous and randomly aligned nanotubes.

  2. Advanced biomolecular materials based on membrane-protein/polymer complexation

    SciTech Connect

    Smith, G.S.; Nowak, A.; Safinya, C.

    1998-12-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of this project was to apply neutron reflectometry and atomic force microscopy to the study of lipid membranes containing proteins. Standard sample preparation techniques were used to produce thin films of these materials appropriate for these techniques. However, these films were not stable, and a new sample preparation technique was required. Toward this goal, the authors have developed a new capability to produce large, freely suspended films of lipid multi-bilayers appropriate for these studies. This system includes a controlled temperature/humidity oven in which the films 5-cm x 5-cm are remotely drawn. The first neutron scattering experiments were then performed using this oven.

  3. ADVANCED POWER SYSTEMS ANALYSIS TOOLS

    SciTech Connect

    Robert R. Jensen; Steven A. Benson; Jason D. Laumb

    2001-08-31

    The use of Energy and Environmental Research Center (EERC) modeling tools and improved analytical methods has provided key information in optimizing advanced power system design and operating conditions for efficiency, producing minimal air pollutant emissions and utilizing a wide range of fossil fuel properties. This project was divided into four tasks: the demonstration of the ash transformation model, upgrading spreadsheet tools, enhancements to analytical capabilities using the scanning electron microscopy (SEM), and improvements to the slag viscosity model. The ash transformation model, Atran, was used to predict the size and composition of ash particles, which has a major impact on the fate of the combustion system. To optimize Atran key factors such as mineral fragmentation and coalescence, the heterogeneous and homogeneous interaction of the organically associated elements must be considered as they are applied to the operating conditions. The resulting model's ash composition compares favorably to measured results. Enhancements to existing EERC spreadsheet application included upgrading interactive spreadsheets to calculate the thermodynamic properties for fuels, reactants, products, and steam with Newton Raphson algorithms to perform calculations on mass, energy, and elemental balances, isentropic expansion of steam, and gasifier equilibrium conditions. Derivative calculations can be performed to estimate fuel heating values, adiabatic flame temperatures, emission factors, comparative fuel costs, and per-unit carbon taxes from fuel analyses. Using state-of-the-art computer-controlled scanning electron microscopes and associated microanalysis systems, a method to determine viscosity using the incorporation of grey-scale binning acquired by the SEM image was developed. The image analysis capabilities of a backscattered electron image can be subdivided into various grey-scale ranges that can be analyzed separately. Since the grey scale's intensity is

  4. Advancing Polymer-Supported Ionogel Electrolytes Formed via Radical Polymerization

    NASA Astrophysics Data System (ADS)

    Visentin, Adam F.

    Applications ranging from consumer electronics to the electric grid have placed demands on current energy storage technologies. There is a drive for devices that store more energy for rapid consumption in the case of electric cars and the power grid, and safer, versatile design options for consumer electronics. Electrochemical double-layer capacitors (EDLCs) are an option that has garnered attention as a means to address these varied energy storage demands. EDLCs utilize charge separation in electrolytes to store energy. This energy storage mechanism allows for greater power density (W kg -1) than batteries and higher energy density (Wh kg-1) than conventional capacitors - along with a robust lifetime in the range of thousands to millions of charge-discharge cycles. Safety and working voltage windows of EDLCs currently on the market are limited by the organic solvents utilized in the electrolyte. A potential solution lies in the replacement of the organic solvents with ionic liquids, or room-temperature molten salts. Ionic liquids possess many superior properties in comparison to conventional solvents: wide electrochemical window, low volatility, nonflammability, and favorable ionic conductivity. It has been an endeavor of this work to exploit these advantages while altering the liquid form factor into a gel. An ionic liquid/solid support scaffold composite electrolyte, or ionogel, adds additional benefits: flexible device design, lower encapsulation weight, and elimination of electrolyte leakage. This work has focused on investigations of a UV-polymerizable monomer, poly(ethylene glycol) diacrylate, as a precursor for forming ionogels in situ. The trade-off between gaining mechanical stability at the cost of ionic conductivity has been investigated for numerous ionogel systems. While gaining a greater understanding of the interactions between the gel scaffold and ionic liquid, an ionogel with the highest known ionic conductivity to date (13.1 mS cm-1) was

  5. Advanced manufacturing by spray forming: Aluminum strip and microelectromechanical systems

    SciTech Connect

    McHugh, K.M.

    1994-12-31

    Spray forming is an advanced materials processing technology that converts a bulk liquid metal to a near-net-shape solid by depositing atomized droplets onto a suitably shaped substrate. By combining rapid solidification processing with product shape control, spray forming can reduce manufacturing costs while improving product quality. INEL is developing a unique spray-forming method based on de Laval (converging/diverging) nozzle designs to produce near-net-shape solids and coatings of metals, polymers, and composite materials. Properties of the spray-formed material are tailored by controlling the characteristics of the spray plume and substrate. Two examples are described: high-volume production of aluminum alloy strip, and the replication of micron-scale features in micropatterned polymers during the production of microelectromechanical systems.

  6. Advanced Overfire Air system and design

    SciTech Connect

    Gene berkau

    2004-07-30

    The objective of the proposed project is to design, install and optimize a prototype advanced tangential OFA air system on two mass feed stoker boilers that can burn coal, biomass and a mixture of these fuels. The results will be used to develop a generalized methodology for retrofit designs and optimization of advanced OFA air systems. The advanced OFA system will reduce particulate and NOx emissions and improve overall efficiency by reducing carbon in the ash and excess oxygen. The advanced OFA will also provide capabilities for carrying full load and improved load following and transitional operations.

  7. Advanced Chemical Propulsion System Study

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

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

  8. Compositions, methods, and systems comprising fluorous-soluble polymers

    DOEpatents

    Swager, Timothy M.; Lim, Jeewoo; Takeda, Yohei

    2015-10-13

    The present invention generally relates to compositions, methods, and systems comprising polymers that are fluorous-soluble and/or organize at interfaces between a fluorous phase and a non-fluorous phase. In some embodiments, emulsions or films are provided comprising a polymer. The polymers, emulsions, and films can be used in many applications, including for determining, treating, and/or imaging a condition and/or disease in a subject. The polymer may also be incorporated into various optoelectronic device such as photovoltaic cells, organic light-emitting diodes, organic field effect transistors, or the like. In some embodiments, the polymers comprise pi-conjugated backbones, and in some cases, are highly emissive.

  9. Wetting reversal in colloid-polymer systems.

    PubMed

    Blokhuis, Edgar M; Kuipers, Joris

    2010-05-01

    The wetting of a phase-separated colloid-polymer mixture in contact with a hard wall is analyzed using free volume theory in a Nakanishi-Fisher-type approach. We present results for the wetting phase diagram for several model approximations. Our analysis is compared with a previous analysis by Aarts [J. Chem. Phys. 120, 1973 (2004)]. We find that there is a crossover from wetting to drying at a threshold value for the colloid-polymer size ratio and that the transitions are close to the critical point and of second order in nature. PMID:20866234

  10. Eastern Stream Advance Notification System.

    ERIC Educational Resources Information Center

    State Univ. of New York, Oneonta. Coll. at Oneonta. Eastern Stream Center on Resources and Training.

    This directory contains instructions for using the advanced notification form designed to help identify migrant interstate children as they move between states. The form contains spaces for entering information about the children in the migrant family including each child's date of birth, last school name, grade level, and Migrant Education Record…

  11. Advanced Group Support Systems and Facilities

    NASA Technical Reports Server (NTRS)

    Noor, Ahmed K. (Compiler); Malone, John B. (Compiler)

    1999-01-01

    The document contains the proceedings of the Workshop on Advanced Group Support Systems and Facilities held at NASA Langley Research Center, Hampton, Virginia, July 19-20, 1999. The workshop was jointly sponsored by the University of Virginia Center for Advanced Computational Technology and NASA. Workshop attendees came from NASA, other government agencies, industry, and universities. The objectives of the workshop were to assess the status of advanced group support systems and to identify the potential of these systems for use in future collaborative distributed design and synthesis environments. The presentations covered the current status and effectiveness of different group support systems.

  12. Polymer/inorganic nanocomposites with tailored hierarchical structure as advanced dielectric materials

    SciTech Connect

    Manias, Evangelos; Randall, Clive; Tomer, Vivek; Polyzos, Georgios

    2012-01-01

    Most advances and commercial successes of polymer/inorganic nanocomposites rely only on the dispersion of nanoparticles in a polymer matrix. Such approaches leave untapped opportunities where performance can be improved by controlling the larger length-scale structures. Here, we review selected examples where the hierarchical structure (from millimeter to nanometer) is tailored to control the transport properties of the materials, giving rise to marked property enhancements, relevant to dielectric materials for power capacitors. These examples address composite structures that are self-assembled, both at the nm and the micron scales, and, thus, can be produced using standard industrial practices. Specifically, polyethylene (PE) blends or poly(vinylidene fluoride) (PVDF) copolymers are reinforced with nanofillers; these composites are designed with high filler orientation, which yielded marked improvements in electric-field breakdown strength and, consequently, large improvements in their recoverable energy densities.

  13. Semi-2-interpenetrating polymer networks of high temperature systems

    NASA Technical Reports Server (NTRS)

    Hanky, A. O.; St. Clair, T. L.

    1985-01-01

    A semi-interpenetrating (semi-IPN) polymer system of the semi-2-IPN type is described in which a polymer of acetylene-terminated imidesulfone (ATPISO2) is cross linked in the presence of polyimidesulfone (PISO2). Six different formulations obtained by mixing of either ATPISO2-1n or ATPISO2-3n with PISO2 in three different proportions were characterized in terms of glass transition temperature, thermooxidative stability, inherent viscosity, and dynamic mechanical properties. Adhesive (lap shear) strength was tested at elevated temperatures on aged samples of adhesive scrim cloth prepared from each resin. Woven graphite (Celion 1000)/polyimide composites were tested for flexural strength, flexural modulus, and shear strength. The network polymers have properties intermediate between those of the component polymers alone, have greatly improved processability over either polyimide, and are able to form good adhesive bonds and composites, making the semi-2-IPN systems superior materials for aerospace structures.

  14. COMBINED MICROBIAL SURFACTANT-POLYMER SYSTEM FOR IMPROVED OIL MOBILITY AND CONFORMANCE CONTROL

    SciTech Connect

    Jorge Gabitto; Maria Barrufet

    2004-08-01

    Many domestic oil fields are facing abandonment even though they still contain two-thirds of their original oil. A significant number of these fields can yield additional oil using advanced oil recovery (AOR) technologies. To maintain domestic oil production at current levels, AOR technologies are needed that are affordable and can be implemented by independent oil producers of the future. Microbial enhanced oil recovery (MEOR) technologies have become established as cost-effective solutions for declining oil production. MEOR technologies are affordable for independent producers operating stripper wells and can be used to extend the life of marginal fields. The demonstrated versatility of microorganisms can be used to design advanced microbial systems to treat multiple production problems in complex, heterogeneous reservoirs. The proposed research presents the concept of a combined microbial surfactant-polymer system for advanced oil recovery. The surfactant-polymer system utilizes bacteria that are capable of both biosurfactant production and metabolically-controlled biopolymer production. This novel technology combines complementary mechanisms to extend the life of marginal fields and is applicable to a large number of domestic reservoirs. The research project described in this report is performed jointly by, Bio-Engineering Inc., a woman owned small business, Texas A&M University and Prairie View A&M University, a Historically Black College and University. This report describes the results of our laboratory work to grow microbial cultures and the work done on recovery experiments on core rocks. We have selected two bacterial strains capable of producing both surfactant and polymers. We have conducted laboratory experiments to determine under what conditions surfactants and polymers can be produced from one single strain. We have conduct recovery experiments to determine the performance of these strains under different conditions. Our results do not show a

  15. Nanoparticles as strengthening agents in polymer systems

    NASA Astrophysics Data System (ADS)

    Shahid, Naureen

    2005-11-01

    Carboxylate-substituted alumina nanoparticles are produced solvent free using mechanical shear. The general nature of this method has been demonstrated for L-lysine-, stearate, and p-hydroxybenzoate-derived materials. The reaction rate and particle size is controlled by a combination of temperature and shear rate. The nanoparticles are spectroscopically equivalent to those reported from aqueous syntheses, however, the average particle size can be decreased and the particle size distribution narrowed depending on the reaction conditions. Lysine and p-hydroxybenzoato alumoxanes have been introduced in carbon fiber reinforced epoxide resin composites. Different preparation conditions have been studied to obtain composite with enhanced performances that are ideal for the motor sports and aerospace industries. A new composite material has been fabricated utilizing surface-modified carboxylate alumoxane nanoparticles and the biodegradable polymer poly(propylene fumarate)/poly(propylene fumarate)-diacrylate (PPF/PPF-DA). For this study, composites were prepared using various functional groups including: a surfactant alumoxane to enhance nanoparticle dispersion into the polymer; an activated-alumoxane to enhance nanoparticle interaction with the polymer matrix; a mixed alumoxane containing both activated and surfactant groups. Nanocomposites prepared with all types of alumoxane, as well as blank polymer resin and unmodified boehmite, underwent mechanical testing and were characterized by SEM and microprobe analysis. A nanocomposite composed of mixed alumoxane nanoparticles dispersed in PPF/PPF-DA exhibited increased flexural modulus compared to polymer resin alone, and a significant enhancement over both the activated and surfacted alumoxanes. Boric acid is used as the cross-linking agent in oil well drilling industry even though the efficacy of the borate ion, [B(OH)4]- , as a cross-linking agent is poor. The reaction product of boric acid and the polysaccharide guaran

  16. Assurance Technology Challenges of Advanced Space Systems

    NASA Technical Reports Server (NTRS)

    Chern, E. James

    2004-01-01

    The initiative to explore space and extend a human presence across our solar system to revisit the moon and Mars post enormous technological challenges to the nation's space agency and aerospace industry. Key areas of technology development needs to enable the endeavor include advanced materials, structures and mechanisms; micro/nano sensors and detectors; power generation, storage and management; advanced thermal and cryogenic control; guidance, navigation and control; command and data handling; advanced propulsion; advanced communication; on-board processing; advanced information technology systems; modular and reconfigurable systems; precision formation flying; solar sails; distributed observing systems; space robotics; and etc. Quality assurance concerns such as functional performance, structural integrity, radiation tolerance, health monitoring, diagnosis, maintenance, calibration, and initialization can affect the performance of systems and subsystems. It is thus imperative to employ innovative nondestructive evaluation methodologies to ensure quality and integrity of advanced space systems. Advancements in integrated multi-functional sensor systems, autonomous inspection approaches, distributed embedded sensors, roaming inspectors, and shape adaptive sensors are sought. Concepts in computational models for signal processing and data interpretation to establish quantitative characterization and event determination are also of interest. Prospective evaluation technologies include ultrasonics, laser ultrasonics, optics and fiber optics, shearography, video optics and metrology, thermography, electromagnetics, acoustic emission, x-ray, data management, biomimetics, and nano-scale sensing approaches for structural health monitoring.

  17. Advanced Mirror System Demonstrator (AMSD) Risk Management

    NASA Technical Reports Server (NTRS)

    Byberg, Alicia; Russell, J. Kevin; Kaukler, Donna; Burdine, Robert V. (Technical Monitor)

    2002-01-01

    This paper will report risk issues associated with designing, manufacturing, and testing the Advanced Mirror System Demonstrator (AMSD). The Advanced Mirror System Demonstrator (AMSD) will be developed as a lightweight primary mirror system that can be produced at a low cost and with a short manufacturing schedule. This technology will add to the knowledge base for selection for the Next Generation Space Telescope (NGST), Space Based Laser (SBL), Research Laboratory mission (AFRL), and other government agency programs.

  18. Transmitter function of synapse-structure system using conducting polymer

    NASA Astrophysics Data System (ADS)

    Fujii, Masaharu; Machiya, Yuka; Ihori, Haruo

    2012-04-01

    Conducting polymers with neuron-like pattern has been polymerized by controlling polymerization conditions. These conducting polymers have been connected each other to prepare network. If the synapse function can be added to the network, artificial neural network is prepared by conducting polymer. In this paper, we consider the transmitter function using synapse-structure conducting polymer. It consists of three parts: primary circuit as presynaptic terminal, space as synaptic cleft and secondary circuit as postsynaptic structure. Dopant in conducting polymer works as neurotransmitter. Migration as well as diffusion is also considered for dopant ion to transit the space/cleft. When signals from the primary circuit came at the end of the primary circuit in electrolyte solution, the current in the secondary circuit increased because the released dopant ion transited the cleft and entered another conducting polymer. When two primary circuits was used, the current in the secondary circuit increased higher than one primary circuit. This means the synapse-structured conducting polymer system can be use as logical circuit.

  19. Recent advances in solid polymer electrolyte fuel cell technology with low platinum loading electrodes

    NASA Technical Reports Server (NTRS)

    Srinivasan, Supramaniam; Manko, David J.; Koch, Hermann; Enayetullah, Mohammad A.; Appleby, A. John

    1989-01-01

    Of all the fuel cell systems only alkaline and solid polymer electrolyte fuel cells are capable of achieving high power densities (greater than 1 W/sq cm) required for terrestrial and extraterrestrial applications. Electrode kinetic criteria for attaining such high power densities are discussed. Attainment of high power densities in solid polymer electrolyte fuel cells has been demonstrated earlier by different groups using high platinum loading electrodes (4 mg/sq cm). Recent works at Los Alamos National Laboratory and at Texas A and M University (TAMU) demonstrated similar performance for solid polymer electrolyte fuel cells with ten times lower platinum loading (0.45 mg/sq cm) in the electrodes. Some of the results obtained are discussed in terms of the effects of type and thickness of membrane and of the methods platinum localization in the electrodes on the performance of a single cell.

  20. Resin systems for producing polymer concrete

    SciTech Connect

    Kukacka, L.E.

    1988-09-01

    When plastics are combined with mixtures of inorganic materials, high-strength, durable, fast-setting composites are produced. These materials are used in structural engineering and other applications, and as a result of the many commercial successes that have been achieved, considerable research and development work is in progress throughout the world. One family of polymer-based composites receiving considerable attention is called polymer concrete. Work in this area is directed toward developing new high-strength durable materials by combining cement and concrete technology with that of polymer chemistry. The purpose of this paper is to discuss the types of resins that can be used to form polymer concretes. Resin selection is normally based upon the desired properties for the composite and cost. However, the physical and chemical properties of the resins before and during curing are also important, particularly for field-applied materials. Currently, for normal temperature (0/degree/ to 30/degree/C) applications, epoxy resins, vinyl monomers such as polyester-styrene, methylmethacrylate, furfuryl alcohol, furan derivatives, urethane, and styrene, are being used. Styrene-trimethylolpropane trimethacrylate (TMPTMA) mixtures and styrene-acrylamide-TMPTMA mixtures yield composites with excellent hydrothermal stability at temperatures up to 150/degree/ and 250/degree/C, respectively, and organosiloxane resins have been successfully tested at 300/degree/C. Of equal importance is the selection of the composition of the inorganic phase of the composite, since chemical interactions between the two phases can significantly enhance the final properties. Further work to elucidate the mechanisms of these interactions is needed. 6 refs.

  1. Spectroradiometric considerations for advanced land observing systems

    NASA Technical Reports Server (NTRS)

    Slater, P. N.

    1986-01-01

    Research aimed at improving the inflight absolute radiometric calibration of advanced land observing systems was initiated. Emphasis was on the satellite sensor calibration program at White Sands. Topics addressed include: absolute radiometric calibration of advanced remote sensing; atmospheric effects on reflected radiation; inflight radiometric calibration; field radiometric methods for reflectance and atmospheric measurement; and calibration of field relectance radiometers.

  2. Aqueous polymer two-phase systems formed by new thermoseparating polymers.

    PubMed

    Persson, J; Johansson, H O; Galaev, I; Mattiasson, B; Tjerneld, F

    2000-01-01

    A set of new polymers that can be used as phase forming components in aqueous two-phase systems is presented. All polymers studied have thermoseparating properties i.e. form one separate polymer enriched phase and one aqueous solution when heated above the critical temperature. This property makes the polymers attractive alternatives to the polymers used in traditional aqueous two-phase systems such as poly(ethylene glycol) (PEG) and dextran. The thermal phase separation simplifies recycling of the polymers, thus making the aqueous two-phase systems more cost efficient and suitable for use in large scale. Thermoseparating polymers studied have been copolymers of ethylene oxide and propylene oxide (EO-PO), poly (N-isopropylacrylamide) (poly-NIPAM), poly vinyl caprolactam (poly-VCL) and copolymers of N-isopropylacrylamide and vinyl caprolactam with vinyl imidazole (poly(NIPAM-VI) and poly(VCL-VI), respectively). In addition, the copolymer poly(NIPAM-VI) has the property to be uncharged at pH above 7.0 and positively charged at lower pH. This allows the partitioning of protein to be directed by changing the pH in the system instead of the traditional addition of salt to direct the partitioning. Hydrophobically modified EO-PO copolymer (HM-(EO-PO)) with alkyl groups (C14) at both ends forms two-phase system with for example poly(NIPAM-VI). The phase diagram for poly(NIPAM-VI)/HM-(EO-PO) was determined and the model proteins lysozyme and BSA were partitioned in this system. For BSA in poly(NIPAM-VI)/HM-(EO-PO) system a change in pH from 8.0 to 5.4 results in a change of partition coefficient from K = 0.8 to K = 5.1, i.e. BSA could be transferred from the HM-(EO-PO) phase to the poly(NIPAM-VI) phase. BSA partitioning in poly(NIPAM-VI)/HM-(EO-PO) system allows quantitative BSA recovery, and recoveries of poly(NIPAM-VI) and HM-(EO-PO) were 53% and 92%, respectively, after the thermoseparation step. PMID:10892544

  3. Large deformation polymer optical fiber sensors for civil infrastructure systems

    NASA Astrophysics Data System (ADS)

    Abdi, Omid; Kowalsky, Mervyn; Hassan, Tasnim; Kiesel, Sharon; Peters, Kara

    2008-03-01

    This paper presents intrinsic polymer fiber (POF) sensors for high-strain applications such as the performance-based assessment and health monitoring of civil infrastructure systems subjected to earthquake loading or morphing aircraft. POFs provide a potential maximum strain range of 6-12%, are more flexible that silica optical fibers, and are more durable in harsh chemical or environmental conditions. Recent advances in the fabrication of single mode POFs have made it possible to extend POFs to interferometric sensor capabilities. Furthermore, the interferometric nature of intrinsic sensors permits high accuracy for such measurements. Measurements of the mechanical response of the sensor at various strain rates are presented. Several cleaving methods were also tested in order to appropriately cleave POFs for coupling purposes. In addition, the design of a time-of-flight interferometer for phase measurements over the large strain range required is discussed. Finally the bond strength between the embedded POF and various structural materials is investigated and a methodology demonstrated for embedment of the sensors into a reinforced concrete structural component.

  4. Advances in the biomedical application of polymer-functionalized carbon nanotubes.

    PubMed

    Soleyman, Rouhollah; Hirbod, Sorina; Adeli, Mohsen

    2015-05-01

    Nowadays, carbon nanotubes (CNTs) have attracted the attention of scientists because of their unique electronic, magnetic, optical, mechanical, and chemical properties. However, their poor solubility in solvents, especially in water, limits their applications in several promising fields such as biomedicine, biomedical imaging, and cancer therapy. The attachment of hydrophilic segments to CNTs is a very efficient method for overcoming this problem. This review covers the latest advances in the synthesis of water-soluble CNTs with an emphasis on the molecular structure of various categories of hydrophilic molecules/macromolecules which have been grafted onto the surface of CNTs. Indeed, from the viewpoint of chemical synthesis, covalent bonding of several water-soluble molecules/macromolecules including small water-soluble organic molecules, linear, hyperbranched and dendritic polymers/biopolymers, glycoconjugate molecules/polymers as well as biomolecules onto the surface of CNTs has been deeply surveyed. Moreover, the most recent and interesting bio-applications of polymer-functionalized water-soluble CNTs have been properly reviewed. PMID:26222588

  5. Polymers.

    ERIC Educational Resources Information Center

    Tucker, David C.

    1986-01-01

    Presents an open-ended experiment which has students exploring polymer chemistry and reverse osmosis. This activity involves construction of a polymer membrane, use of it in a simple osmosis experiment, and application of its principles in solving a science-technology-society problem. (ML)

  6. A molecular dynamics study of polymer/graphene interfacial systems

    SciTech Connect

    Rissanou, Anastassia N.; Harmandaris, Vagelis

    2014-05-15

    Graphene based polymer nanocomposites are hybrid materials with a very broad range of technological applications. In this work, we study three hybrid polymer/graphene interfacial systems (polystyrene/graphene, poly(methyl methacrylate)/graphene and polyethylene/graphene) through detailed atomistic molecular dynamics (MD) simulations. Density profiles, structural characteristics and mobility aspects are being examined at the molecular level for all model systems. In addition, we compare the properties of the hybrid systems to the properties of the corresponding bulk ones, as well as to theoretical predictions.

  7. Engine health monitoring: An advanced system

    NASA Technical Reports Server (NTRS)

    Dyson, R. J. E.

    1981-01-01

    The advanced propulsion monitoring system is described. The system was developed in order to fulfill a growing need for effective engine health monitoring. This need is generated by military requirements for increased performance and efficiency in more complex propulsion systems, while maintaining or improving the cost to operate. This program represents a vital technological step in the advancement of the state of the art for monitoring systems in terms of reliability, flexibility, accuracy, and provision of user oriented results. It draws heavily on the technology and control theory developed for modern, complex, electronically controlled engines and utilizes engine information which is a by-product of such a system.

  8. Nonelastomeric Rod Seals for Advanced Hydraulic Systems

    NASA Technical Reports Server (NTRS)

    Hady, W. F.; Waterman, A. W.

    1976-01-01

    Advanced high temperature hydraulic system rod sealing requirements can be met by using seals made of nonelastomeric (plastic) materials in applications where elastomers do not have adequate life. Exploratory seal designs were optimized for advanced applications using machinable polyimide materials. These seals demonstrated equivalent flight hour lives of 12,500 at 350 F and 9,875 at 400 F in advanced hydraulic system simulation. Successful operation was also attained under simulated space shuttle applications; 96 reentry thermal cycles and 1,438 hours of vacuum storage. Tests of less expensive molded plastic seals indicated a need for improved materials to provide equivalent performance to the machined seals.

  9. Diffusion in Entangled and Surface Modified Polymer Systems

    NASA Astrophysics Data System (ADS)

    Tead, Stanley Fromm

    Ion beam analysis techniques were used to measure the concentration vs. depth profiles of deuterium labelled polymer molecules in unlabeled and/or chemically dissimilar polymer melts, for several polymer systems. In the first polymer system, the tracer diffusion coefficient of deuterated polystyrene (d-PS) molecules was measured in polystyrene (PS) matrices which were blends of high molecular weight (volume fraction phi) and low molecular weight PS. The dependence of the d-PS diffusion coefficient on phi was quantitatively predicted by the models of reptation and constraint release. In the second polymer system, diffusion of polystyrenes was studied with ring shaped chains substituted (instead of linear ones) in the tracer and/or matrix roles. The diffusion of linear tracers into ring matrices was nearly identical to linear tracer diffusion in linear matrices, a result not predicted by any current theories. Dry etching of polystyrene by four different ion and plasma methods crosslinked the exposed surface monolayer, immobilizing it and reducing its permeability to diffusion by unetched tracer molecules. The integrated thickness of the immobile layer is decreased for an increased ratio of chain scission to crosslinking. The ratio is smallest for reactive ion beam etching, intermediate for reactive ion etching, and largest for the pure plasma techniques. Diffusion was investigated in systems of the polymer polyimide (PI), produced by the imidization of polyamic acid at a temperature T_{rm i }. The effects of thermal processing (imidization) of the polymer and exposure to solvents were studied. The diffusion of deuterated polyamic acid in PI was reduced to negligible levels for T_{rm i}'s at or above 200^circ C; purely thermally activated diffusion (in the absence of solvents) was not seen for any combination of annealing temperatures up to 400^circ C. Ion beam analysis methods were developed to measure the kinetics and depth dependence of the imidization reaction in

  10. Advances in uncooled systems applications

    NASA Astrophysics Data System (ADS)

    Anderson, John S.; Bradley, Daryl; Chen, Chungte W.; Chin, Richard; Gonzalez, H.; Hegg, Ronald G.; Kostrzewa, K.; Le Pere, C.; Ton, S.; Kennedy, Adam; Murphy, Daniel F.; Ray, Michael; Wyles, Richard; Miller, James E.; Newsome, Gwendolyn W.

    2003-09-01

    The Low Cost Microsensors (LCMS) Program recently demonstrated state-of-the-art imagery in a long-range infrared (IR) sensor built upon an uncooled vanadium oxide (VOx) 640 x 480 format focal plane array (FPA) engine. The 640 x 480 sensor is applicable to long-range surveillance and targeting missions. The intent of this DUS&T effort was to further reduce the cost, weight, and power of uncooled IR sensors, and to increase the capability of these sensors, thereby expanding their applicability to military and commercial markets never before addressed by thermal imaging. In addition, the Advanced Uncooled Thermal Imaging Sensors (AUTIS) Program extended this development to light-weight, compact unmanned aerial vehicle (UAV) applications.

  11. Advanced rheological characterization of soft colloidal model systems

    NASA Astrophysics Data System (ADS)

    Gupta, S.; Kundu, S. K.; Stellbrink, J.; Willner, L.; Allgaier, J.; Richter, D.

    2012-11-01

    The complex flow behavior of polymer-based soft colloidal model systems was investigated using steady and oscillatory shear to prove new concepts for advanced rheological characterization. In the very dilute regime we investigated high molecular weight polybutadiene star polymers to quantify the internal relaxation time arising from the polymeric nature of these ultra-soft colloids. The observed shear-induced brush deformation is interpreted in terms of the internal Zimm time τz. The observed dependence of τz on matrix viscosity can be explained by shrinkage of the star polymer due to an increasing incompatibility with increasing matrix molecular weight. The influence of the polymeric nature on the characteristic structural relaxation time in the concentrated regime was investigated using non-linear rheology following Wyss et al (SRFS) (2007 Phys. Rev. Lett. 98 238303). Here we used star-like block copolymer micelles to systematically tune the ‘softness’ of the colloids by variation of the block ratio. A master curve with proper scaling parameters could be generated independent of the degree of colloidal ‘softness’. However, the obtained strain-rate independent structural relaxation time τ0 was not observed in the linear regime. In addition, a high frequency discrepancy was clearly found in all our experimental data. Both reflect the shortcomings of the SRFS approach.

  12. Advanced air revitalization system testing

    NASA Technical Reports Server (NTRS)

    Heppner, D. B.; Hallick, T. M.; Schubert, F. H.

    1983-01-01

    A previously developed experimental air revitalization system was tested cyclically and parametrically. One-button startup without manual interventions; extension by 1350 hours of tests with the system; capability for varying process air carbon dioxide partial pressure and humidity and coolant source for simulation of realistic space vehicle interfaces; dynamic system performance response on the interaction of the electrochemical depolarized carbon dioxide concentrator, the Sabatier carbon dioxide reduction subsystem, and the static feed water electrolysis oxygen generation subsystem, the carbon dioxide concentrator module with unitized core technology for the liquid cooled cell; and a preliminary design for a regenerative air revitalization system for the space station are discussed.

  13. Erosion Coatings for High-Temperature Polymer Composites: A Collaborative Project With Allison Advanced Development Company

    NASA Technical Reports Server (NTRS)

    Sutter, James K.

    2000-01-01

    The advantages of replacing metals in aircraft turbine engines with high-temperature polymer matrix composites (PMC's) include weight savings accompanied by strength improvements, reduced part count, and lower manufacturing costs. Successfully integrating high-temperature PMC's into turbine engines requires several long-term characteristics. Resistance to surface erosion is one rarely reported property of PMC's in engine applications because PMC's are generally softer than metals and their erosion resistance suffers. Airflow rates in stationary turbine engine components typically exceed 2.3 kg/sec at elevated temperatures and pressures. In engine applications, as shown in the following photos, the survivability of PMC components is clearly a concern, especially when engine and component life-cycle requirements become longer. Although very few publications regarding the performance of erosion coatings on PMC's are available particularly in high-temperature applications the use of erosion-resistant coatings to significantly reduce wear on metallic substrates is well documented. In this study initiated by the NASA Glenn Research Center at Lewis Field, a low-cost (less than $140/kg) graphite-fiber-reinforced T650 35/PMR 15 sheet-molding compound was investigated with various coatings. This sheet-molding compound has been compression molded into many structurally complicated components, such as shrouds for gas turbine inlet housings and gearboxes. Erosion coatings developed for PMC s in this study consisted of a two-layered system: a bondcoat sprayed onto a cleaned PMC surface, followed by an erosion-resistant, hard topcoat sprayed onto the bondcoat as shown in following photomicrograph. Six erosion coating systems were evaluated for their ability to withstand harsh thermal cycles, erosion resistance (ASTM G76 83 "Standard Practice for Conducting Erosion Tests by Solid Particle Impingement Using Gas Jets") using Al2O3, and adhesion to the graphite fiber polyimide

  14. Hybrid and Electric Advanced Vehicle Systems Simulation

    NASA Technical Reports Server (NTRS)

    Beach, R. F.; Hammond, R. A.; Mcgehee, R. K.

    1985-01-01

    Predefined components connected to represent wide variety of propulsion systems. Hybrid and Electric Advanced Vehicle System (HEAVY) computer program is flexible tool for evaluating performance and cost of electric and hybrid vehicle propulsion systems. Allows designer to quickly, conveniently, and economically predict performance of proposed drive train.

  15. Characterization of advanced electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Ray, P. K.

    1982-01-01

    Characteristic parameters of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, argon MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. Overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

  16. Advanced EVA system design requirements study

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Design requirements and criteria for the Space Station Advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related extravehicular activity (EVA) support equipment were defined and established. The EVA mission requirements, environments, and medical and physiological requirements, as well as opertional, procedures, and training issues were considered.

  17. Creep-Fatigue Relationsihps in Electroactive Polymer Systems and Predicted Effects in an Actuator Design

    NASA Technical Reports Server (NTRS)

    Vinogradov, Aleksandra M.; Ihlefeld, Curtis M.; Henslee, Issac

    2009-01-01

    The paper concerns the time-dependent behavior of electroactive polymers (EAP) and their use in advanced intelligent structures for space exploration. Innovative actuator design for low weight and low power valves required in small plants planned for use on the moon for chemical analysis is discussed. It is shown that in-depth understanding of cyclic loading effects observed through accelerated creep rates due to creep-fatigue interaction in polymers is critical in terms of proper functioning of EAP based actuator devices. In the paper, an overview of experimental results concerning the creep properties and cyclic creep response of a thin film piezoelectric polymer polyvinylidene fluoride (PVDF) is presented. The development of a constitutive creep-fatigue interaction model to predict the durability and service life of electroactive polymers is discussed. A novel method is proposed to predict damage accumulation and fatigue life of polymers under oyclic loading conditions in the presence of creep. The study provides a basis for ongoing research initiatives at the NASA Kennedy Space Center in the pursuit of new technologies using EAP as active elements for lunar exploration systems.

  18. Demonstration Advanced Avionics System (DAAS)

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The feasibility of developing an integrated avionics system suitable for general aviation was determined. A design of reliable integrated avionics which provides expanded functional capability that significantly enhances the utility and safety of general aviation at a cost commensurate with the general aviation market was developed. The use of a data bus, microprocessors, electronic displays and data entry devices, and improved function capabilities were emphasized. An avionics system capable of evaluating the most critical and promising elements of an integrated system was designed, built and flight tested in a twin engine general aviation aircraft.

  19. US Advanced Freight and Passenger MAGLEV System

    NASA Technical Reports Server (NTRS)

    Morena, John J.; Danby, Gordon; Powell, James

    1996-01-01

    Japan and Germany will operate first generation Maglev passenger systems commercially shortly after 2000 A.D. The United States Maglev systems will require sophisticated freight and passenger carrying capability. The U.S. freight market is larger than passenger transport. A proposed advanced freight and passenger Maglev Project in Brevard County Florida is described. Present Maglev systems cost 30 million dollars or more per mile. Described is an advanced third generation Maglev system with technology improvements that will result in a cost of 10 million dollars per mile.

  20. Advanced Power System Analysis Capabilities

    NASA Technical Reports Server (NTRS)

    1997-01-01

    As a continuing effort to assist in the design and characterization of space power systems, the NASA Lewis Research Center's Power and Propulsion Office developed a powerful computerized analysis tool called System Power Analysis for Capability Evaluation (SPACE). This year, SPACE was used extensively in analyzing detailed operational timelines for the International Space Station (ISS) program. SPACE was developed to analyze the performance of space-based photovoltaic power systems such as that being developed for the ISS. It is a highly integrated tool that combines numerous factors in a single analysis, providing a comprehensive assessment of the power system's capability. Factors particularly critical to the ISS include the orientation of the solar arrays toward the Sun and the shadowing of the arrays by other portions of the station.

  1. Enhanced Two-Stage Reactive Polymer Network Forming Systems

    PubMed Central

    Nair, Devatha P.; Cramer, Neil B.; McBride, Matthew K.; Gaipa, John C.; Shandas, Robin; Bowman, Christopher N.

    2012-01-01

    In this study, we develop thiol/acrylate two-stage reactive network forming polymer systems that exhibit two distinct and orthogonal stages of curing. Using a thiol-acrylate system with excess acrylate functional groups, a first stage polymer network is formed via a 1 to 1 stoichiometric thiol-acrylate Michael addition reaction (stage 1). At a later point in time, the excess acrylate functional groups are homopolymerized via a photoinitiated free radical polymerization to form a second stage polymer network (stage 2). By varying the monomers within the system as well as the stoichiometery of the thiol to acrylate functional groups, we demonstrate the ability of the two-stage polymer network forming systems to encompass a wide range of properties at the end of both the stage 1 and stage 2 polymerizations. Using urethane di- and hexa-acrylates within the formulations led to two-stage reactive polymeric systems with stage 1 Tgs that ranged from −12 to 30 °C. The systems were then photocured, upon which the Tg of the systems increases by up to 90 °C while also achieving a nearly 20 fold modulus increase. PMID:22798700

  2. Separation of aqueous two-phase polymer systems in microgravity

    NASA Technical Reports Server (NTRS)

    Vanalstine, J. M.; Harris, J. M.; Synder, S.; Curreri, P. A.; Bamberger, S. B.; Brooks, D. E.

    1984-01-01

    Phase separation of polymer systems in microgravity is studied in aircraft flights to prepare shuttle experiments. Short duration (20 sec) experiments demonstrate that phase separation proceeds rapidly in low gravity despite appreciable phase viscosities and low liquid interfacial tensions (i.e., 50 cP, 10 micro N/m). Ostwald ripening does not appear to be a satisfactory model for the phase separation mechanism. Polymer coated surfaces are evaluated as a means to localize phases separated in low gravity. Contact angle measurements demonstrate that covalently coupling dextran or PEG to glass drastically alters the 1-g wall wetting behavior of the phases in dextran-PEG two phase systems.

  3. Advanced Sensor Systems for Biotelemetry

    NASA Technical Reports Server (NTRS)

    Hines, John W. (Inventor); Somps, Christopher J. (Inventor); Ricks, Robert D. (Inventor); Mundt, Carsten W. (Inventor)

    2003-01-01

    The present invention relates to telemetry-based sensing systems that continuously measures physical, chemical and biological parameters. More specifically, these sensing systems comprise a small, modular, low-power implantable biotelemetry system capable of continuously sensing physiological characteristics using implantable transmitters, a receiver, and a data acquisition system to analyze and record the transmitted signal over several months. The preferred embodiment is a preterm labor and fetal monitoring system. Key features of the invention include Pulse Interval Modulation (PIM) that is used to send temperature and pressure information out of the biological environment. The RF carrier frequency is 174-216 MHz and a pair of RF bursts (pulses) is transmitted at a frequency of about 1-2 Hz. The transmission range is 3 to 10 feet, depending on the position of the transmitter in the body and its biological environment. The entire transmitter is encapsulated in biocompatible silicone rubber. Power is supplied by on-board silver-oxide batteries. The average power consumption of the current design is less than 30 microW, which yields a lifetime of approximately 6 - 9 months. Chip-on-Board technology (COB) drastically reduces the size of the printed circuit board from 38 x 28 mm to 22 x 8 mm. Unpackaged dies are flip-chip bonded directly onto the printed circuit board, along with surface mount resistors and capacitors. The invention can monitor additional physiological parameters including, but not limited to, ECG, blood gases, glucose, and ions such as calcium, potassium, and sodium.

  4. Modeling Advance Life Support Systems

    NASA Technical Reports Server (NTRS)

    Pitts, Marvin; Sager, John; Loader, Coleen; Drysdale, Alan

    1996-01-01

    Activities this summer consisted of two projects that involved computer simulation of bioregenerative life support systems for space habitats. Students in the Space Life Science Training Program (SLSTP) used the simulation, space station, to learn about relationships between humans, fish, plants, and microorganisms in a closed environment. One student complete a six week project to modify the simulation by converting the microbes from anaerobic to aerobic, and then balancing the simulation's life support system. A detailed computer simulation of a closed lunar station using bioregenerative life support was attempted, but there was not enough known about system restraints and constants in plant growth, bioreactor design for space habitats and food preparation to develop an integrated model with any confidence. Instead of a completed detailed model with broad assumptions concerning the unknown system parameters, a framework for an integrated model was outlined and work begun on plant and bioreactor simulations. The NASA sponsors and the summer Fell were satisfied with the progress made during the 10 weeks, and we have planned future cooperative work.

  5. Advanced action manipulator system (ADAMS)

    NASA Technical Reports Server (NTRS)

    Kugath, D. A.; Dane, D. H.; Blaise, H. T.

    1973-01-01

    Manipulator offers improved performance over other models in its category. It features larger force and reach capabilities and is readily convertible for underwater use. Unique kinematic arrangement provides extremely large working envelope. System has six degrees of motion: azimuth joint, shoulder joint, upper arm rotating joint, elbow joint, wrist pitch, and wrist twist.

  6. Advanced sensor systems for biotelemetry

    NASA Technical Reports Server (NTRS)

    Hines, John W. (Inventor); Somps, Christopher J. (Inventor); Ricks, Robert D. (Inventor); Mundt, Carsten W. (Inventor)

    2003-01-01

    The present invention relates to telemetry-based sensing systems that continuously measures physical, chemical and biological parameters. More specifically, these sensing systems comprise a small, modular, low-power implantable biotelemetry system capable of continuously sensing physiological characteristics using implantable transmitters, a receiver, and a data acquisition system to analyze and record the transmitted signal over several months. The preferred embodiment is a preterm labor and fetal monitoring system. Key features of the invention include Pulse Interval Modulation (PIM) that is used to send temperature and pressure information out of the biological environment. The RF carrier frequency is 174-216 MHz and a pair of RF bursts (pulses) is transmitted at a frequency of about 1-2 Hz. The transmission range is 3 to 10 feet, depending on the position of the transmitter in the body and its biological environment. The entire transmitter is encapsulated in biocompatible silicone rubber. Power is supplied by on-board silver-oxide batteries. The average power consumption of the current design is less than 30 .mu.W., which yields a lifetime of approximately 6-9 months. Chip-on-Board technology (COB) drastically reduces the size of the printed circuit board from 38.times.28 mm to 22.times.8 mm. Unpackaged dies are flip-chip bonded directly onto the printed circuit board, along with surface mount resistors and capacitors. The invention can monitor additional physiological parameters including, but not limited to, ECG, blood gases, glucose, and ions such as calcium, potassium, and sodium.

  7. Development of Advanced Alarm System for SMART

    SciTech Connect

    Jang, Gwi-sook; Seoung, Duk-hyun; Suh, Sang-moon; Lee, Jong-bok; Park, Geun-ok; Koo, In-soo

    2004-07-01

    A SMART-Alarm System (SMART-AS) is a new system being developed as part of the SMART (System-integrated Modular Advanced Reactor) project. The SMART-AS employs modern digital technology to implement the alarm functions of the SMART. The use of modern digital technology can provide advanced alarm processing in which new algorithms such as a signal validation, advanced alarm processing logic and other features are applied to improve the control room man-machine interfaces. This paper will describe the design process of the SMART-AS, improving the system reliability and availability using the reliability prediction tool, design strategies regarding the human performance topics associated with a computer-based SMART-AS and the results of the performance analysis using a prototype of the SMART-AS. (authors)

  8. Combustion modeling in advanced gas turbine systems

    SciTech Connect

    Smoot, L.D.; Hedman, P.O.; Fletcher, T.H.; Brewster, B.S.; Kramer, S.K.

    1995-12-31

    Goal of DOE`s Advanced Turbine Systems program is to develop and commercialize ultra-high efficiency, environmentally superior, cost competitive gas turbine systems for base-load applications in utility, independent power producer, and industrial markets. Primary objective of the program here is to develop a comprehensive combustion model for advanced gas turbine combustion systems using natural gas (coal gasification or biomass fuels). The efforts included code evaluation (PCGC-3), coherent anti-Stokes Raman spectroscopy, laser Doppler anemometry, and laser-induced fluorescence.

  9. Westinghouse advanced particle filter system

    SciTech Connect

    Lippert, T.E.; Bruck, G.J.; Sanjana, Z.N.; Newby, R.A.

    1994-10-01

    Integrated Gasification Combined Cycles (IGCC) and Pressurized Fluidized Bed Combustion (PFBC) are being developed and demonstrated for commercial, power generation application. Hot gas particulate filters are key components for the successful implementation of IGCC and PFBC in power generation gas turbine cycles. The objective of this work is to develop and qualify through analysis and testing a practical hot gas ceramic barrier filter system that meets the performance and operational requirements of PFBC and IGCC systems. This paper updates the assessment of the Westinghouse hot gas filter design based on ongoing testing and analysis. Results are summarized from recent computational fluid dynamics modeling of the plenum flow during back pulse, analysis of candle stressing under cleaning and process transient conditions and testing and analysis to evaluate potential flow induced candle vibration.

  10. Advances in Microsphere Insulation Systems

    NASA Astrophysics Data System (ADS)

    Allen, M. S.; Baumgartner, R. G.; Fesmire, J. E.; Augustynowicz, S. D.

    2004-06-01

    Microsphere insulation, typically consisting of hollow glass bubbles, combines in a single material the desirable properties that other insulations only have individually. The material has high crush strength, low density, is noncombustible, and performs well in soft vacuum. Microspheres provide robust, low-maintenance insulation systems for cryogenic transfer lines and dewars. They also do not suffer from compaction problems typical of perlite that result in the necessity to reinsulate dewars because of degraded thermal performance and potential damage to its support system. Since microspheres are load bearing, autonomous insulation panels enveloped with lightweight vacuum-barrier materials can be created. Comprehensive testing performed at the Cryogenics Test Laboratory located at the NASA Kennedy Space Center demonstrated competitive thermal performance with other bulk materials. Test conditions were representative of actual-use conditions and included cold vacuum pressure ranging from high vacuum to no vacuum and compression loads from 0 to 20 psi. While microspheres have been recognized as a legitimate insulation material for decades, actual implementation has not been pursued. Innovative microsphere insulation system configurations and applications are evaluated.

  11. Advanced secondary power system for transport aircraft

    NASA Technical Reports Server (NTRS)

    Hoffman, A. C.; Hansen, I. G.; Beach, R. F.; Plencner, R. M.; Dengler, R. P.; Jefferies, K. S.; Frye, R. J.

    1985-01-01

    A concept for an advanced aircraft power system was identified that uses 20-kHz, 440-V, sin-wave power distribution. This system was integrated with an electrically powered flight control system and with other aircraft systems requiring secondary power. The resulting all-electric secondary power configuration reduced the empty weight of a modern 200-passenger, twin-engine transport by 10 percent and the mission fuel by 9 percent.

  12. Advanced Energy Efficient Roof System

    SciTech Connect

    Jane Davidson

    2008-09-30

    Energy consumption in buildings represents 40 percent of primary U.S. energy consumption, split almost equally between residential (22%) and commercial (18%) buildings.1 Space heating (31%) and cooling (12%) account for approximately 9 quadrillion Btu. Improvements in the building envelope can have a significant impact on reducing energy consumption. Thermal losses (or gains) from the roof make up 14 percent of the building component energy load. Infiltration through the building envelope, including the roof, accounts for an additional 28 percent of the heating loads and 16 percent of the cooling loads. These figures provide a strong incentive to develop and implement more energy efficient roof systems. The roof is perhaps the most challenging component of the building envelope to change for many reasons. The engineered roof truss, which has been around since 1956, is relatively low cost and is the industry standard. The roof has multiple functions. A typical wood frame home lasts a long time. Building codes vary across the country. Customer and trade acceptance of new building products and materials may impede market penetration. The energy savings of a new roof system must be balanced with other requirements such as first and life-cycle costs, durability, appearance, and ease of construction. Conventional residential roof construction utilizes closely spaced roof trusses supporting a layer of sheathing and roofing materials. Gypsum board is typically attached to the lower chord of the trusses forming the finished ceiling for the occupied space. Often in warmer climates, the HVAC system and ducts are placed in the unconditioned and otherwise unusable attic. High temperature differentials and leaky ducts result in thermal losses. Penetrations through the ceilings are notoriously difficult to seal and lead to moisture and air infiltration. These issues all contribute to greater energy use and have led builders to consider construction of a conditioned attic. The

  13. The Advanced Technology Operations System: ATOS

    NASA Technical Reports Server (NTRS)

    Kaufeler, J.-F.; Laue, H. A.; Poulter, K.; Smith, H.

    1993-01-01

    Mission control systems supporting new space missions face ever-increasing requirements in terms of functionality, performance, reliability and efficiency. Modern data processing technology is providing the means to meet these requirements in new systems under development. During the past few years the European Space Operations Centre (ESOC) of the European Space Agency (ESA) has carried out a number of projects to demonstrate the feasibility of using advanced software technology, in particular, knowledge based systems, to support mission operations. A number of advances must be achieved before these techniques can be moved towards operational use in future missions, namely, integration of the applications into a single system framework and generalization of the applications so that they are mission independent. In order to achieve this goal, ESA initiated the Advanced Technology Operations System (ATOS) program, which will develop the infrastructure to support advanced software technology in mission operations, and provide applications modules to initially support: Mission Preparation, Mission Planning, Computer Assisted Operations, and Advanced Training. The first phase of the ATOS program is tasked with the goal of designing and prototyping the necessary system infrastructure to support the rest of the program. The major components of the ATOS architecture is presented. This architecture relies on the concept of a Mission Information Base (MIB) as the repository for all information and knowledge which will be used by the advanced application modules in future mission control systems. The MIB is being designed to exploit the latest in database and knowledge representation technology in an open and distributed system. In conclusion the technological and implementation challenges expected to be encountered, as well as the future plans and time scale of the project, are presented.

  14. Coordination polymer particles as potential drug delivery systems.

    PubMed

    Imaz, Inhar; Rubio-Martínez, Marta; García-Fernández, Lorena; García, Francisca; Ruiz-Molina, Daniel; Hernando, Jordi; Puntes, Victor; Maspoch, Daniel

    2010-07-14

    Micro- and nanoscale coordination polymer particles can be used for encapsulating and delivering drugs. In vitro cancer cell cytotoxicity assays showed that these capsules readily release doxorubicin, which shows anticancer efficacy. The results from this work open up new avenues for metal-organic capsules to be used as potential drug delivery systems. PMID:20485835

  15. Hybrid energy harvesting systems, using piezoelectric elements and dielectric polymers

    NASA Astrophysics Data System (ADS)

    Cornogolub, Alexandru; Cottinet, Pierre-Jean; Petit, Lionel

    2016-09-01

    Interest in energy harvesting applications has increased a lot during recent years. This is especially true for systems using electroactive materials like dielectric polymers or piezoelectric materials. Unfortunately, these materials despite multiple advantages, present some important drawbacks. For example, many dielectric polymers demonstrated high energy densities; they are cheap, easy to process and can be easily integrated in many different structures. But at the same time, dielectric polymer generators require an external energy supply which could greatly compromise their autonomy. Piezoelectric systems, on the other hand, are completely autonomous and can be easily miniaturized. However, most common piezoelectric materials present a high rigidity and are brittle by nature and therefore their integration could be difficult. This paper investigates the possibility of using hybrid systems combining piezoelectric elements and dielectric polymers for mechanical energy harvesting applications and it is focused mainly on the problem of electrical energy transfer. Our objective is to show that such systems can be interesting and that it is possible to benefit from the advantages of both materials. For this, different configurations were considered and the problem of their optimization was addressed. The experimental work enabled us to prove the concept and identify the main practical limitations.

  16. Liquid-liquid equilibrium of aqueous two-polymer systems

    SciTech Connect

    Kang, C.H.

    1988-01-01

    The authors consider the thermodynamic description of the liquid-liquid phase behavior of dextran/polyethylene glycol/water systems which are suitable for the purification or isolation of biological materials. In this effort, they have used the Flory-Huggins and UNIQUAC models and developed a new numerical procedure to estimate the interaction parameters of the models. To test the predictive ability of the models for the phase behavior of the systems, the interaction parameters between each polymer and water were obtained from binary osmotic pressure data so that only the interaction parameters between the unlike polymers were estimated by fitting the ternary LLE data. Both of the models with the parameters obtained in this way gave reasonable predictions of the phase boundaries; the two-parameter UNIQUAC model appeared to be superior to the three-parameter Flory-Huggins model. The phase boundaries of polydisperse aqueous two-phase polymer systems were determined with pseudocomponents chosen based on the Gaussian quadrature methods, and the effects of polymer polydispersivity on the phase boundary were investigated. The predictive versions of Flory-Huggins and the UNIQUAC models were used for the thermodynamic description of these systems together with the assumption of continuous distributions for the molecular weight of the polydisperse species.

  17. Optimal size for emergence of self-replicating polymer system

    NASA Astrophysics Data System (ADS)

    Matsubara, Yoshiya J.; Kaneko, Kunihiko

    2016-03-01

    A biological system consists of a variety of polymers that are synthesized from monomers by catalysis, which exists only for some long polymers. It is important to elucidate the emergence and sustenance of such autocatalytic polymerization. We analyze here the stochastic polymerization reaction dynamics to investigate the transition time from a state with almost no catalysts to a state with sufficient catalysts. We found an optimal volume that minimizes this transition time, which agrees with the inverse of the catalyst concentration at the unstable fixed point that separates the two states, as is theoretically explained. Relevance to the origin of life is also discussed.

  18. Technical Considerations for Advanced Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.

    1999-01-01

    This presentation reviews concerns involving advanced propulsion systems. The problems involved with the use of Am-242m, is that it has a high "eta" plus an order of magnitude larger fission cross section than other fissionable materials, and that it is extremely rare. However other americium isotopes are much more common, but extremely effective isotopic separation is required. Deuterium-Tritium fusion is also not attractive for space propulsion applications. Because the pulsed systems cannot breed adequate amounts of tritium and it is difficult and expensive to bring tritium from Earth. The systems that do breed tritium have severely limited performance. However, other fusion processes should still be evaluated. Another problem with advanced propellants is that inefficiencies in converting the total energy generated into propellant energy can lead to tremendous heat rejection requirements. Therefore Many. advanced propulsion concepts benefit greatly from low-mass radiators.

  19. Printed polymer photonic devices for optical interconnect systems

    NASA Astrophysics Data System (ADS)

    Subbaraman, Harish; Pan, Zeyu; Zhang, Cheng; Li, Qiaochu; Guo, L. J.; Chen, Ray T.

    2016-03-01

    Polymer photonic device fabrication usually relies on the utilization of clean-room processes, including photolithography, e-beam lithography, reactive ion etching (RIE) and lift-off methods etc, which are expensive and are limited to areas as large as a wafer. Utilizing a novel and a scalable printing process involving ink-jet printing and imprinting, we have fabricated polymer based photonic interconnect components, such as electro-optic polymer based modulators and ring resonator switches, and thermo-optic polymer switch based delay networks and demonstrated their operation. Specifically, a modulator operating at 15MHz and a 2-bit delay network providing up to 35.4ps are presented. In this paper, we also discuss the manufacturing challenges that need to be overcome in order to make roll-to-roll manufacturing practically viable. We discuss a few manufacturing challenges, such as inspection and quality control, registration, and web control, that need to be overcome in order to realize true implementation of roll-to-roll manufacturing of flexible polymer photonic systems. We have overcome these challenges, and currently utilizing our inhouse developed hardware and software tools, <10μm alignment accuracy at a 5m/min is demonstrated. Such a scalable roll-to-roll manufacturing scheme will enable the development of unique optoelectronic devices which can be used in a myriad of different applications, including communication, sensing, medicine, security, imaging, energy, lighting etc.

  20. Advanced two-photon photolithography for patterning of transparent, electrically conductive ionic liquid-polymer nanostructures

    NASA Astrophysics Data System (ADS)

    Bakhtina, Natalia A.; MacKinnon, Neil; Korvink, Jan G.

    2016-04-01

    A key challenge in micro- and nanotechnology is the direct patterning of functional structures. For example, it is highly desirable to possess the ability to create three-dimensional (3D), conductive, and optically transparent structures. Efforts in this direction have, to date, yielded less than optimal results since the polymer composites had low optical transparency over the visible range, were only slightly conductive, or incompatible with high resolution structuring. We have previously presented the novel cross-linkable, conductive, highly transparent composite material based on a photoresist (IP-L 780, OrmoComp, or SU-8) and the ionic liquid 1-butyl-3-methylimidazolium dicyanamide. Material patterning by conventional and two-photon photolithography has been demonstrated as proof-of-concept. Aiming to increase the resolution and to extend the spectrum of exciting applications we continued our research into identifying new ionic liquid - polymer composites. In this paper, we report the precise 3D single-step structuring of optically transparent and electrically conductive ionic liquid - polymer nanostructures with the highest spatial resolution (down to 150 nm) achieved to date. This was achieved via the development of novel cross-linkable composite based on the photoresist IP-G 780 and the ionic liquid 1-butyl-3-methylimidazolium dicyanamide. The successful combination of the developed material with the advanced direct laser writing technique enabled the time- and cost-saving direct manufacturing of transparent, electrically conductive components. We believe that the excellent characteristics of the structured material will open a wider range of exciting applications.

  1. Learning to Control Advanced Life Support Systems

    NASA Technical Reports Server (NTRS)

    Subramanian, Devika

    2004-01-01

    Advanced life support systems have many interacting processes and limited resources. Controlling and optimizing advanced life support systems presents unique challenges. In particular, advanced life support systems are nonlinear coupled dynamical systems and it is difficult for humans to take all interactions into account to design an effective control strategy. In this project. we developed several reinforcement learning controllers that actively explore the space of possible control strategies, guided by rewards from a user specified long term objective function. We evaluated these controllers using a discrete event simulation of an advanced life support system. This simulation, called BioSim, designed by Nasa scientists David Kortenkamp and Scott Bell has multiple, interacting life support modules including crew, food production, air revitalization, water recovery, solid waste incineration and power. They are implemented in a consumer/producer relationship in which certain modules produce resources that are consumed by other modules. Stores hold resources between modules. Control of this simulation is via adjusting flows of resources between modules and into/out of stores. We developed adaptive algorithms that control the flow of resources in BioSim. Our learning algorithms discovered several ingenious strategies for maximizing mission length by controlling the air and water recycling systems as well as crop planting schedules. By exploiting non-linearities in the overall system dynamics, the learned controllers easily out- performed controllers written by human experts. In sum, we accomplished three goals. We (1) developed foundations for learning models of coupled dynamical systems by active exploration of the state space, (2) developed and tested algorithms that learn to efficiently control air and water recycling processes as well as crop scheduling in Biosim, and (3) developed an understanding of the role machine learning in designing control systems for

  2. Plan for an Advanced Turbine Systems Program

    SciTech Connect

    Bajura, R.A.; Webb, H.A.; Parks, W.P.

    1993-03-01

    A draft version of this paper was presented at the Clemson Clean, affordable, and reliable natural gas utilization technologies will play a growing role in meeting future power generation needs in the United States. The US Department of Energy`s (DOE) National Energy Strategy projected that total demand for natural gas will rise from 18.5 trillion cubic feet (tcf) in 1990 to 24.2 tcf by the year 2000. Much of this increase is attributed to the increased use of natural gas as a fuel for electric power generation. Candidate technologies for gas fired power generation include gas turbine and fuel cell systems. The first workshop on research needs for advanced gas turbine systems for power generation was held on April 8-10, 1991 in Greenville, South Carolina. The goals of the Clemson-I Workshop were to identify research needs which would accelerate the development of advanced gas turbines and to consider new approaches to implement this research. The Clemson-I Workshop focused on advanced gas turbine systems which would have a lower cost of electricity or better environmental performance than systems currently under development. The workshop was cosponsored by the DOE`s Morgantown Energy Technology Center (METC), Clemson University, and the South Carolina Energy Research and Development Center. The proceedings from the workshop have been published. The 75 participants in the Clemson-I Workshop represented a broad spectrum of the gas turbine Research & Development (R&D) community as well as potential users of advanced gas turbines. Gas turbine manufacturers, the electric utility industry, the university community, as well as government and private sector R&D sponsors were represented. Participants in the Clemson-I Workshop concluded that it is technically feasible to develop advanced turbine systems and that Government participation would accelerate the developmental effort. Advanced turbine systems could be operated on natural gas or adapted to coal or biomass firing.

  3. Plan for an Advanced Turbine Systems Program

    SciTech Connect

    Bajura, R.A.; Webb, H.A. ); Parks, W.P. )

    1993-01-01

    A draft version of this paper was presented at the Clemson Clean, affordable, and reliable natural gas utilization technologies will play a growing role in meeting future power generation needs in the United States. The US Department of Energy's (DOE) National Energy Strategy projected that total demand for natural gas will rise from 18.5 trillion cubic feet (tcf) in 1990 to 24.2 tcf by the year 2000. Much of this increase is attributed to the increased use of natural gas as a fuel for electric power generation. Candidate technologies for gas fired power generation include gas turbine and fuel cell systems. The first workshop on research needs for advanced gas turbine systems for power generation was held on April 8-10, 1991 in Greenville, South Carolina. The goals of the Clemson-I Workshop were to identify research needs which would accelerate the development of advanced gas turbines and to consider new approaches to implement this research. The Clemson-I Workshop focused on advanced gas turbine systems which would have a lower cost of electricity or better environmental performance than systems currently under development. The workshop was cosponsored by the DOE's Morgantown Energy Technology Center (METC), Clemson University, and the South Carolina Energy Research and Development Center. The proceedings from the workshop have been published. The 75 participants in the Clemson-I Workshop represented a broad spectrum of the gas turbine Research Development (R D) community as well as potential users of advanced gas turbines. Gas turbine manufacturers, the electric utility industry, the university community, as well as government and private sector R D sponsors were represented. Participants in the Clemson-I Workshop concluded that it is technically feasible to develop advanced turbine systems and that Government participation would accelerate the developmental effort. Advanced turbine systems could be operated on natural gas or adapted to coal or biomass firing.

  4. COMBINED MICROBIAL SURFACTANT-POLYMER SYSTEM FOR IMPROVED OIL MOBILITY AND CONFORMANCE CONTROL

    SciTech Connect

    Jorge Gabitto; Maria Barrufet

    2005-08-01

    Many domestic oil fields are facing abandonment even though they still contain two-thirds of their original oil. A significant number of these fields can yield additional oil using advanced oil recovery (AOR) technologies. To maintain domestic oil production at current levels, AOR technologies are needed that are affordable and can be implemented by the independent oil producers of the future. Microbial enhanced oil recovery (MEOR) technologies have become established as cost-effective solutions for declining oil production. MEOR technologies are affordable for independent producers operating stripper wells and can be used to extend the life of marginal fields. The demonstrated versatility of microorganisms can be used to design advanced microbial systems to treat multiple production problems in complex, heterogeneous reservoirs. The proposed research presents the concept of a combined microbial surfactant-polymer system for advanced oil recovery. The surfactant-polymer system utilizes bacteria that are capable of both biosurfactant production and metabolically-controlled biopolymer production. This novel technology combines complementary mechanisms to extend the life of marginal fields and is applicable to a large number of domestic reservoirs. The research project described in this report was performed by Bio-Engineering Inc., a woman owned small business, Texas A&M University and Prairie View A&M University, a Historically Black College and University. This report describes the results of our laboratory work to grow microbial cultures, the work done on recovery experiments on core rocks, and computer simulations. We have selected two bacterial strains capable of producing both surfactant and polymers. We have conducted laboratory experiments to determine under what conditions surfactants and polymers can be produced from one single strain. We have conduct recovery experiments to determine the performance of these strains under different conditions. Our results

  5. Advanced Asia's health systems in comparison.

    PubMed

    Gauld, Robin; Ikegami, Naoki; Barr, Michael D; Chiang, Tung-Liang; Gould, Derek; Kwon, Soonman

    2006-12-01

    There is growing interest in comparing patterns of social and health service development in advanced Asian economies. Most publications concentrate broadly on a range of core social services such as education, housing, social security and health care. In terms of those solely focused on health, most discuss arrangements in specific countries and territories. Some take a comparative approach, but are focused on presentation and discussion of expenditure, resourcing and service utilization data. This article extends the comparative analysis of advanced Asian health systems, considering the cases of Japan, South Korea, Taiwan, Hong Kong and Singapore. The article provides basic background information, and delves into common concerns among the world's health systems today including primary care organization, rationing and cost containment, service quality, and system integration. Conclusions include that problems exist in 'classifying' the five diverse systems; that the systems face common pressures; and that there are considerable opportunities to enhance primary care, service quality and system integration. PMID:16517000

  6. Advanced Microgravity Acceleration Measurement Systems Being Developed

    NASA Technical Reports Server (NTRS)

    Sicker, Ronald J.; Kacpura, Thomas J.

    2002-01-01

    The Advanced Microgravity Acceleration Measurement Systems (AMAMS) project at the NASA Glenn Research Center is part of the Instrument Technology Development program to develop advanced sensor systems. The primary focus of the AMAMS project is to develop microelectromechanical (MEMS) acceleration sensor systems to replace existing electromechanical-sensor-based systems presently used to assess relative gravity levels aboard spacecraft. These systems are used in characterizing both vehicle and payload responses to low-gravity vibroacoustic environments. The collection of microgravity acceleration data has cross-disciplinary utility to the microgravity life and physical sciences and the structural dynamics communities. The inherent advantages of semiconductor-based systems are reduced size, mass, and power consumption, while providing enhanced stability.

  7. Stationary market applications potential of solid oxide and solid polymer fuel cell systems

    SciTech Connect

    Baker, J.N.; Fletcher, W.H.

    1996-12-31

    The UK DTI`s Advanced Fuel Cells Programme currently focuses on two main fuel cell technologies, namely the solid oxide and solid polymer systems (SOFC and SPFC), respectively. The provision of accurate and timely market data is regarded as an important part of the overall programme objectives, such as to assist both Government and industry in their appraisals of the technologies. The present study was therefore commissioned against this background, with a complementary study addressing transportation and mobile applications. The results reported herein relate to the stationary market applications potential of both SOFC and SPFC systems.

  8. Advancements in fabrication process of microelectrode array for a retinal prosthesis using Liquid Crystal Polymer (LCP).

    PubMed

    Jeong, Joonsoo; Shin, Soowon; Lee, Geun Jae; Gwon, Tae Mok; Park, Jeong Hoan; Kim, Sung June

    2013-01-01

    Liquid Crystal Polymer (LCP) has been considered as an alternative biomaterial for implantable biomedical devices primarily for its low moisture absorption rate compared with conventional polymers such as polyimide, parylene and silicone elastomers. A novel retinal prosthetic device based on monolithic encapsulation of LCP is being developed in which entire neural stimulation circuitries are integrated into a thin and eye-conformable structure. Micromachining techniques for fabrication of a LCP retinal electrode array have been previously reported. In this research, however, for being used as a part of the LCP-based retinal implant, we developed advanced fabrication process of LCP retinal electrode through new approaches such as electroplating and laser-machining in order to achieve higher mechanical robustness, long-term reliability and flexibility. Thickened metal tracks could contribute to higher mechanical strength as well as higher long-term reliability when combined with laser-ablation process by allowing high-pressure lamination. Laser-thinning technique could improve the flexibility of LCP electrode. PMID:24110931

  9. Advanced Turbine Systems Program. Topical report

    SciTech Connect

    1993-03-01

    The Allison Gas Turbine Division (Allison) of General Motors Corporation conducted the Advanced Turbine Systems (ATS) program feasibility study (Phase I) in accordance with the Morgantown Energy Technology Center`s (METC`s) contract DE-AC21-86MC23165 A028. This feasibility study was to define and describe a natural gas-fired reference system which would meet the objective of {ge}60% overall efficiency, produce nitrogen oxides (NO{sub x}) emissions 10% less than the state-of-the-art without post combustion controls, and cost of electricity of the N{sup th} system to be approximately 10% below that of the current systems. In addition, the selected natural gas-fired reference system was expected to be adaptable to coal. The Allison proposed reference system feasibility study incorporated Allison`s long-term experience from advanced aerospace and military technology programs. This experience base is pertinent and crucial to the success of the ATS program. The existing aeroderivative technology base includes high temperature hot section design capability, single crystal technology, advanced cooling techniques, high temperature ceramics, ultrahigh turbomachinery components design, advanced cycles, and sophisticated computer codes.

  10. Advanced orbit transfer vehicle propulsion system study

    NASA Technical Reports Server (NTRS)

    Cathcart, J. A.; Cooper, T. W.; Corringrato, R. M.; Cronau, S. T.; Forgie, S. C.; Harder, M. J.; Mcallister, J. G.; Rudman, T. J.; Stoneback, V. W.

    1985-01-01

    A reuseable orbit transfer vehicle concept was defined and subsequent recommendations for the design criteria of an advanced LO2/LH2 engine were presented. The major characteristics of the vehicle preliminary design include a low lift to drag aerocapture capability, main propulsion system failure criteria of fail operational/fail safe, and either two main engines with an attitude control system for backup or three main engines to meet the failure criteria. A maintenance and servicing approach was also established for the advanced vehicle and engine concepts. Design tradeoff study conclusions were based on the consideration of reliability, performance, life cycle costs, and mission flexibility.

  11. Study of mould design and forming process on advanced polymer-matrix composite complex structure

    NASA Astrophysics Data System (ADS)

    Li, S. J.; Zhan, L. H.; Bai, H. M.; Chen, X. P.; Zhou, Y. Q.

    2015-07-01

    Advanced carbon fibre-reinforced polymer-matrix composites are widely applied to aviation manufacturing field due to their outstanding performance. In this paper, the mould design and forming process of the complex composite structure were discussed in detail using the hat stiffened structure as an example. The key issues of the moulddesign were analyzed, and the corresponding solutions were also presented. The crucial control points of the forming process such as the determination of materials and stacking sequence, the temperature and pressure route of the co-curing process were introduced. In order to guarantee the forming quality of the composite hat stiffened structure, a mathematical model about the aperture of rubber mandrel was introduced. The study presented in this paper may provide some actual references for the design and manufacture of the important complex composite structures.

  12. Advanced optical blade tip clearance measurement system

    NASA Technical Reports Server (NTRS)

    Ford, M. J.; Honeycutt, R. E.; Nordlund, R. E.; Robinson, W. W.

    1978-01-01

    An advanced electro-optical system was developed to measure single blade tip clearances and average blade tip clearances between a rotor and its gas path seal in an operating gas turbine engine. This system is applicable to fan, compressor, and turbine blade tip clearance measurement requirements, and the system probe is particularly suitable for operation in the extreme turbine environment. A study of optical properties of blade tips was conducted to establish measurement system application limitations. A series of laboratory tests was conducted to determine the measurement system's operational performance characteristics and to demonstrate system capability under simulated operating gas turbine environmental conditions. Operational and environmental performance test data are presented.

  13. Advanced tracking systems design and analysis

    NASA Technical Reports Server (NTRS)

    Potash, R.; Floyd, L.; Jacobsen, A.; Cunningham, K.; Kapoor, A.; Kwadrat, C.; Radel, J.; Mccarthy, J.

    1989-01-01

    The results of an assessment of several types of high-accuracy tracking systems proposed to track the spacecraft in the National Aeronautics and Space Administration (NASA) Advanced Tracking and Data Relay Satellite System (ATDRSS) are summarized. Tracking systems based on the use of interferometry and ranging are investigated. For each system, the top-level system design and operations concept are provided. A comparative system assessment is presented in terms of orbit determination performance, ATDRSS impacts, life-cycle cost, and technological risk.

  14. Modeling of Spacecraft Advanced Chemical Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Benfield, Michael P. J.; Belcher, Jeremy A.

    2004-01-01

    This paper outlines the development of the Advanced Chemical Propulsion System (ACPS) model for Earth and Space Storable propellants. This model was developed by the System Technology Operation of SAIC-Huntsville for the NASA MSFC In-Space Propulsion Project Office. Each subsystem of the model is described. Selected model results will also be shown to demonstrate the model's ability to evaluate technology changes in chemical propulsion systems.

  15. Advanced Radioisotope Power Systems Segmented Thermoelectric Research

    NASA Technical Reports Server (NTRS)

    Caillat, Thierry

    2004-01-01

    Flight times are long; - Need power systems with >15 years life. Mass is at an absolute premium; - Need power systems with high specific power and scalability. 3 orders of magnitude reduction in solar irradiance from Earth to Pluto. Nuclear power sources preferable. The Overall objective is to develop low mass, high efficiency, low-cost Advanced Radioisotope Power System with double the Specific Power and Efficiency over state-of-the-art Radioisotope Thermoelectric Generators (RTGs).

  16. Advanced Computed-Tomography Inspection System

    NASA Technical Reports Server (NTRS)

    Harris, Lowell D.; Gupta, Nand K.; Smith, Charles R.; Bernardi, Richard T.; Moore, John F.; Hediger, Lisa

    1993-01-01

    Advanced Computed Tomography Inspection System (ACTIS) is computed-tomography x-ray apparatus revealing internal structures of objects in wide range of sizes and materials. Three x-ray sources and adjustable scan geometry gives system unprecedented versatility. Gantry contains translation and rotation mechanisms scanning x-ray beam through object inspected. Distance between source and detector towers varied to suit object. System used in such diverse applications as development of new materials, refinement of manufacturing processes, and inspection of components.

  17. Advanced Seismic While Drilling System

    SciTech Connect

    Robert Radtke; John Fontenot; David Glowka; Robert Stokes; Jeffery Sutherland; Ron Evans; Jim Musser

    2008-06-30

    . An APS Turbine Alternator powered the SeismicPULSER{trademark} to produce two Hz frequency peak signals repeated every 20 seconds. Since the ION Geophysical, Inc. (ION) seismic survey surface recording system was designed to detect a minimum downhole signal of three Hz, successful performance was confirmed with a 5.3 Hz recording with the pumps running. The two Hz signal generated by the sparker was modulated with the 3.3 Hz signal produced by the mud pumps to create an intense 5.3 Hz peak frequency signal. The low frequency sparker source is ultimately capable of generating selectable peak frequencies of 1 to 40 Hz with high-frequency spectra content to 10 kHz. The lower frequencies and, perhaps, low-frequency sweeps, are needed to achieve sufficient range and resolution for realtime imaging in deep (15,000 ft+), high-temperature (150 C) wells for (a) geosteering, (b) accurate seismic hole depth, (c) accurate pore pressure determinations ahead of the bit, (d) near wellbore diagnostics with a downhole receiver and wired drill pipe, and (e) reservoir model verification. Furthermore, the pressure of the sparker bubble will disintegrate rock resulting in an increased overall rates of penetration. Other applications for the SeismicPULSER{trademark} technology are to deploy a low-frequency source for greater range on a wireline for Reverse Vertical Seismic Profiling (RVSP) and Cross-Well Tomography. Commercialization of the technology is being undertaken by first contacting stakeholders to define the value proposition for rig site services utilizing SeismicPULSER{trademark} technologies. Stakeholders include national oil companies, independent oil companies, independents, service companies, and commercial investors. Service companies will introduce a new Drill Bit SWD service for deep HTHP wells. Collaboration will be encouraged between stakeholders in the form of joint industry projects to develop prototype tools and initial field trials. No barriers have been identified

  18. Noise impact of advanced high lift systems

    NASA Technical Reports Server (NTRS)

    Elmer, Kevin R.; Joshi, Mahendra C.

    1995-01-01

    The impact of advanced high lift systems on aircraft size, performance, direct operating cost and noise were evaluated for short-to-medium and medium-to-long range aircraft with high bypass ratio and very high bypass ratio engines. The benefit of advanced high lift systems in reducing noise was found to be less than 1 effective-perceived-noise decibel level (EPNdB) when the aircraft were sized to minimize takeoff gross weight. These aircraft did, however, have smaller wings and lower engine thrusts for the same mission than aircraft with conventional high lift systems. When the advanced high lift system was implemented without reducing wing size and simultaneously using lower flap angles that provide higher L/D at approach a cumulative noise reduction of as much as 4 EPNdB was obtained. Comparison of aircraft configurations that have similar approach speeds showed cumulative noise reduction of 2.6 EPNdB that is purely the result of incorporating advanced high lift system in the aircraft design.

  19. Advanced rotorcraft helmet display sighting system optics

    NASA Astrophysics Data System (ADS)

    Raynal, Francois; Chen, Muh-Fa

    2002-08-01

    Kaiser Electronics' Advanced Rotorcraft Helmet Display Sighting System is a Biocular Helmet Mounted Display (HMD) for Rotary Wing Aviators. Advanced Rotorcraft HMDs requires low head supported weight, low center of mass offsets, low peripheral obstructions of the visual field, large exit pupils, large eye relief, wide field of view (FOV), high resolution, low luning, sun light readability with high contrast and low prismatic deviations. Compliance with these safety, user acceptance and optical performance requirements is challenging. The optical design presented in this paper provides an excellent balance of these different and conflicting requirements. The Advanced Rotorcraft HMD optical design is a pupil forming off axis catadioptric system that incorporates a transmissive SXGA Active Matrix liquid Crystal Display (AMLCD), an LED array backlight and a diopter adjustment mechanism.

  20. Advanced insulations for refrigerator/freezers: The potential for new shell designs incorporating polymer barrier construction

    SciTech Connect

    Griffith, B.T.; Arasteh, D.

    1992-11-01

    The impending phase-out of chlorofluorocarbons (CFCs) used to expand foam insulation, combined with requirements for increased energy efficiency, make the use of non-CFC-based high performance insulation technologies increasingly attractive. The majority of current efforts are directed at using advanced insulations in the form of thin, flat low-conductivity gas-filled or evacuated orthogonal panels, which we refer to as Advanced Insulation Panels (AIPs). AIPs can be used in composite with blown polymer foams to improve insulation performance in refrigerator/freezers (R/Fs) of conventional design and manufacture. This AIP/foam composite approach is appealing because it appears to be a feasible, near-term method for incorporating advanced insulations into R/Fs without substantial redesign or retooling. However, the requirements for adequate flow of foam during the foam-in-place operation impose limitations on the allowable thickness and coverage area of AIPs. This report examines design alternatives which may offer a greater increase in overall thermal resistance than is possible with the use of AIP/foam composites in current R/F design. These design alternatives generally involve a basic redesign of the R/F taking into account the unique requirements of advanced insulations and the importance of minimizing thermal bridging with high thermal resistance insulations. The focus here is on R/F doors because they are relatively simple and independent R/F components and are therefore good candidates for development of alterative designs. R/F doors have significant thermal bridging problems due to the steel outer shell construction. A three dimensional finite difference computer modeling exercise of a R/F door geometry was used to compare the overall levels of thermal resistance (R-value) for various design configurations.

  1. Recent advances with generalized entropy theory of glass-formation in polymers

    NASA Astrophysics Data System (ADS)

    Freed, Karl

    The generalized entropy theory (GET) of glass-formation in polymers is a combination of the lattice cluster theory (LCT) for the configurational entropy density with the Adam-Gibbs (AG) theory for the structural relaxation time. A greatly simplified form of the GET (whose expression for the free energy is roughly double that of Flory-Huggins theory) accurately reproduces the four characteristic temperatures of glass-formation (the onset, crossover, glass transition, and Kauzmann temperatures) of the full GET to within 4K for a series of models of polymers composed of semi-flexible chains having the structure of poly(n-alpha olefins). The theory is now simple enough to be used in courses in polymer physics. Although the successes of the GET provide a strong validation of the final form of the AG theory provided the configurational entropy is used, the physical basis of the AG theory has remained an enigma. Hence, we have developed a new, more general, statistical mechanical derivation of AG theory that explains the previously perplexing observations that the string-like elementary excitations have the mass and temperature dependence of systems undergoing equilibrium self-assembly. This work is supported by the (U.S.) Department of Energy (DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award No. DE- SC0008631.

  2. Small-scale polymer structures enabled by thiol-ene copolymer systems

    NASA Astrophysics Data System (ADS)

    Kasprzak, Scott Edward

    2009-12-01

    The research described herein is aimed at exploring the thermomechanical properties of thiol-ene polymers in bulk form, investigating the ability of thiol-ene polymers to behave desirably as photolithographic media, and providing the first characterization of the mechanical properties of two-photon stereolithography-produced polymer structures. The thiol-ene polymerization reaction itself is well-characterized and described in the literature, but the thermomechanical properties of thiol-ene and thiol-ene/acrylate polymers still require more rigorous study. Understanding the behavior of thiol-ene networks is a crucial step towards their expanded use in bulk form, and particularly in specialized applications such as shape memory devices. Additionally, the thiol-ene polymerization reaction mechanism exhibits unique properties which make these polymers well suited to photolithography, overcoming the typical dichotomy of current materials which either exhibit excellent photolithographic behavior or have controllable properties. Finally, before two-photon stereolithography can create mechanisms and devices which can serve any mechanically functional role, the mechanical properties of the polymers they produce must be quantitatively characterized, which is complicated by the extremely small scale at which these structures are produced. As such, mechanical characterization to date has been strictly qualitative. Fourier transfer infrared spectroscopy revealed functional group conversion information and sol-fraction testing revealed the presence of unconverted monomer and impurities, while dynamic mechanical analysis (DMA) and tensile testing revealed the thermomechanical responses of the systems. Nanoindentation was employed to characterize the mechanical properties of micrometer-scale polymer structures produced by two-photon stereolithography. Optical and electron microscopy were exploited to provide both quantitative and qualitative evaluations of thiol-ene/acrylate and

  3. Solid polymer electrolyte water electrolysis system development. [to generate oxygen for manned space station applications

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Solid polymer electrolyte technology used in a water electrolysis system (WES) to generate oxygen and hydrogen for manned space station applications was investigated. A four-man rated, low pressure breadboard water electrolysis system with the necessary instrumentation and controls was fabricated and tested. A six man rated, high pressure, high temperature, advanced preprototype WES was developed. This configuration included the design and development of an advanced water electrolysis module, capable of operation at 400 psig and 200 F, and a dynamic phase separator/pump in place of a passive phase separator design. Evaluation of this system demonstrated the goal of safe, unattended automated operation at high pressure and high temperature with an accumulated gas generation time of over 1000 hours.

  4. Cost estimating methods for advanced space systems

    NASA Technical Reports Server (NTRS)

    Cyr, Kelley

    1988-01-01

    The development of parametric cost estimating methods for advanced space systems in the conceptual design phase is discussed. The process of identifying variables which drive cost and the relationship between weight and cost are discussed. A theoretical model of cost is developed and tested using a historical data base of research and development projects.

  5. Microprocessor controlled advanced battery management systems

    NASA Technical Reports Server (NTRS)

    Payne, W. T.

    1978-01-01

    The advanced battery management system described uses the capabilities of an on-board microprocessor to: (1) monitor the state of the battery on a cell by cell basis; (2) compute the state of charge of each cell; (3) protect each cell from reversal; (4) prevent overcharge on each individual cell; and (5) control dual rate reconditioning to zero volts per cell.

  6. Regolith Advanced Surface Systems Operations Robot Excavator

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Smith, Jonathan D.; Ebert, Thomas; Cox, Rachel; Rahmatian, Laila; Wood, James; Schuler, Jason; Nick, Andrew

    2013-01-01

    The Regolith Advanced Surface Systems Operations Robot (RASSOR) excavator robot is a teleoperated mobility platform with a space regolith excavation capability. This more compact, lightweight design (<50 kg) has counterrotating bucket drums, which results in a net-zero reaction horizontal force due to the self-cancellation of the symmetrical, equal but opposing, digging forces.

  7. Verification testing of advanced environmental monitoring systems

    SciTech Connect

    Kelly, T.J.; Riggs, K.B.; Fuerst, R.G.

    1999-03-01

    This paper describes the Advanced Monitoring Systems (AMS) pilot project, one of 12 pilots comprising the US EPA`s Environmental Technology Verification (ETV) program. The aim of ETV is to promote the acceptance of environmental technologies in the marketplace, through objective third-party verification of technology performance.

  8. Measuring advances in HVAC distribution system designs

    SciTech Connect

    Franconi, Ellen

    1998-07-01

    Substantial commercial building energy savings have been achieved by improving the performance of the HVAC distribution system. The energy savings result from distribution system design improvements, advanced control capabilities, and use of variable-speed motors. Yet, much of the commercial building stock remains equipped with inefficient systems. Contributing to this is the absence of a definition for distribution system efficiency as well as the analysis methods for quantifying performance. This research investigates the application of performance indices to assess design advancements in commercial building thermal distribution systems. The index definitions are based on a first and second law of thermodynamics analysis of the system. The second law or availability analysis enables the determination of the true efficiency of the system. Availability analysis is a convenient way to make system efficiency comparisons since performance is evaluated relative to an ideal process. A TRNSYS simulation model is developed to analyze the performance of two distribution system types, a constant air volume system and a variable air volume system, that serve one floor of a large office building. Performance indices are calculated using the simulation results to compare the performance of the two systems types in several locations. Changes in index values are compared to changes in plant energy, costs, and carbon emissions to explore the ability of the indices to estimate these quantities.

  9. Measuring Advances in HVAC Distribution System Design

    SciTech Connect

    Franconi, E.

    1998-05-01

    Substantial commercial building energy savings have been achieved by improving the performance of the HV AC distribution system. The energy savings result from distribution system design improvements, advanced control capabilities, and use of variable-speed motors. Yet, much of the commercial building stock remains equipped with inefficient systems. Contributing to this is the absence of a definition for distribution system efficiency as well as the analysis methods for quantifying performance. This research investigates the application of performance indices to assess design advancements in commercial building thermal distribution systems. The index definitions are based on a first and second law of thermodynamics analysis of the system. The second law or availability analysis enables the determination of the true efficiency of the system. Availability analysis is a convenient way to make system efficiency comparisons since performance is evaluated relative to an ideal process. A TRNSYS simulation model is developed to analyze the performance of two distribution system types, a constant air volume system and a variable air volume system, that serve one floor of a large office building. Performance indices are calculated using the simulation results to compare the performance of the two systems types in several locations. Changes in index values are compared to changes in plant energy, costs, and carbon emissions to explore the ability of the indices to estimate these quantities.

  10. Overview of Advanced Turbine Systems Program

    NASA Astrophysics Data System (ADS)

    Webb, H. A.; Bajura, R. A.

    The US Department of Energy initiated a program to develop advanced gas turbine systems to serve both central power and industrial power generation markets. The Advanced Turbine Systems (ATS) Program will lead to commercial offerings by the private sector by 2002. ATS will be developed to fire natural gas but will be adaptable to coal and biomass firing. The systems will be: highly efficient (15 percent improvement over today's best systems); environmentally superior (10 percent reduction in nitrogen oxides over today's best systems); and cost competitive (10 percent reduction in cost of electricity). The ATS Program has five elements. Innovative cycle development will lead to the demonstration of systems with advanced gas turbine cycles using current gas turbine technology. High temperature development will lead to the increased firing temperatures needed to achieve ATS Program efficiency goals. Ceramic component development/demonstration will expand the current DOE/CE program to demonstrate industrial-scale turbines with ceramic components. Technology base will support the overall program by conducting research and development (R&D) on generic technology issues. Coal application studies will adapt technology developed in the ATS program to coal-fired systems being developed in other DOE programs.

  11. Advanced Atmospheric Water Vapor DIAL Detection System

    NASA Technical Reports Server (NTRS)

    Refaat, Tamer F.; Elsayed-Ali, Hani E.; DeYoung, Russell J. (Technical Monitor)

    2000-01-01

    Measurement of atmospheric water vapor is very important for understanding the Earth's climate and water cycle. The remote sensing Differential Absorption Lidar (DIAL) technique is a powerful method to perform such measurement from aircraft and space. This thesis describes a new advanced detection system, which incorporates major improvements regarding sensitivity and size. These improvements include a low noise advanced avalanche photodiode detector, a custom analog circuit, a 14-bit digitizer, a microcontroller for on board averaging and finally a fast computer interface. This thesis describes the design and validation of this new water vapor DIAL detection system which was integrated onto a small Printed Circuit Board (PCB) with minimal weight and power consumption. Comparing its measurements to an existing DIAL system for aerosol and water vapor profiling validated the detection system.

  12. Advanced Polymer Technology for Containing and Immobilizing Strontium-90 in the Subsurface - 8361

    SciTech Connect

    K. Baker; G. Heath; C. Scott; A. Schafer; S. Bryant; M. Sharma; C. Huh; S. K. Choi

    2008-02-01

    Many Department of Energy (DOE) sites, including Idaho and Hanford, have heavy metals and/or radionuclides (e.g. strontium-90) present that are strongly adsorbed in the vadose zone, but which nevertheless are propagating toward the water table. A key challenge for immobilization of these contaminants is bringing the chosen amendment or remediation technology into contact with the contaminated porous medium, while ensuring that contaminated water and colloids do not escape. This is particularly challenging when the subsurface geology is complex and highly heterogeneous, as is the case at many DOE sites. The Idaho National Laboratory (INL) in collaboration with the University of Texas at Austin (UT) has conducted research sponsored through the DOE Office of Environmental Management (EM) Advanced Remediation Technologies Phase I program that successfully demonstrated application of a novel, pH-triggered advanced polymer for creating a physical barrier that prevents heavy metals and radionuclides in vadose zone soil and soil-pore water from migrating to the groundwater. The focus of this paper is on the column and sandbox experiments conducted by researchers at the Idaho National Laboratory in support of the Phase I program objectives. Proof of these concepts provides a technology basis for confining or isolating a volume of contaminated groundwater, to be implemented in future investigations at the Vadose Zone Research Park (VZRP) at INL.

  13. Combustion modeling in advanced gas turbine systems

    SciTech Connect

    Smoot, L.D.; Hedman, P.O.; Fletcher, T.H.

    1995-10-01

    The goal of the U.S. Department of Energy`s Advanced Turbine Systems (ATS) program is to help develop and commercialize ultra-high efficiency, environmentally superior, and cost competitive gas turbine systems for base-load applications in the utility, independent power producer, and industrial markets. Combustion modeling, including emission characteristics, has been identified as a needed, high-priority technology by key professionals in the gas turbine industry.

  14. Investigation of novel electrolyte systems for advanced metal/air batteries and fuel cells

    NASA Astrophysics Data System (ADS)

    Ye, Hui

    It is a worldwide challenge to develop advanced green power sources for modern portable devices, transportation and stationary power generation. Metal/air batteries and fuel cells clearly stand out in view of their high specific energy, high energy efficiency and environment-friendliness. Advanced metal/air batteries based on metal ion conductors and proton exchange membrane (PEM) fuel cells operated at elevated temperatures (>120°C) can circumvent the limitations of current technologies and bring considerable advantages. The key is to develop suitable electrolytes to enable these new technologies. In this thesis research, investigation of novel electrolytes systems for advanced metal/air batteries and PEM fuel cells is conducted. Novel polymer gel electrolyte systems, [metal salt/ionic liquid/polymer] and [metal salt/liquid polyether/polymer] are prepared. Such systems contain no volatile solvents, conduct metal ions (Li+ or Zn 2+) with high ionic conductivity, possess wide electrochemical stability windows, and exhibit wide operating temperature ranges. They promise to enable non-aqueous, all-solid-state, thin-film Li/air batteries and Zn/air batteries. They are advantageous for application in other battery systems as well, such as rechargeable lithium and lithium ion batteries. In the case of proton exchange membranes, polymer gel electrolyte systems [acid/ionic liquid/polymer] are prepared. Especially, H3PO4/PMIH2PO 4/PBI is demonstrated as prospective proton exchange membranes for PEM fuel cells operating at elevated temperatures. Comprehensive electrochemical characterization, thermal analysis (TGA and DSC) and spectroscopy analysis (NMR and FTIR) are carried out to investigate these novel electrolyte systems and their ion transport mechanisms. The design and synthesis of novel ionic liquids and electrolyte systems based on them for advantageous application in various electrochemical power sources are highlighted in this work.

  15. Advances in mechanisms of systemic lupus erythematosus.

    PubMed

    Dema, Barbara; Charles, Nicolas

    2014-05-01

    Systemic lupus erythematosus (SLE) is a complex autoimmune disease associated with hormonal, environmental, and genetic factors and linked to the tolerance breakdown of B and T cells to self-antigens. SLE is characterized by the presence in patient serum of autoantibodies raised against nuclear components. Association of these antibodies to self-antigens, complement factors, DNA, and particular proteins will form circulating immune complexes (CIC) which can deposit in several organs, causing tissue damage and clinical manifestations. Historically, SLE is considered as an adaptive immune system disorder. Over the past decade, advances in the understanding of SLE pathogenesis placed the innate immune system as a key player in perpetuating and amplifying this systemic disease. In this review, we summarize some recent key advances in understanding the SLE immune-pathogenesis with a particular focus on newly discovered key factors from the innate immune system and how they influence the pathogenic adaptive immune system: neutrophils and neutrophil extracellular traps (NETs), plasmacytoid dendritic cells (pDCs) and type I interferons, basophils and autoreactive IgE, monocytes/macrophages and the inflammasome. Recent advances on B and T cell involvement in the SLE pathogenesis mechanisms are also discussed. Although the disease is clinically, genetically, and immunologically heterogeneous between affected individuals, the latest discoveries are offering new promising therapeutic strategies. PMID:24882716

  16. The NASA Advanced Space Power Systems Project

    NASA Technical Reports Server (NTRS)

    Mercer, Carolyn R.; Hoberecht, Mark A.; Bennett, William R.; Lvovich, Vadim F.; Bugga, Ratnakumar

    2015-01-01

    The goal of the NASA Advanced Space Power Systems Project is to develop advanced, game changing technologies that will provide future NASA space exploration missions with safe, reliable, light weight and compact power generation and energy storage systems. The development effort is focused on maturing the technologies from a technology readiness level of approximately 23 to approximately 56 as defined in the NASA Procedural Requirement 7123.1B. Currently, the project is working on two critical technology areas: High specific energy batteries, and regenerative fuel cell systems with passive fluid management. Examples of target applications for these technologies are: extending the duration of extravehicular activities (EVA) with high specific energy and energy density batteries; providing reliable, long-life power for rovers with passive fuel cell and regenerative fuel cell systems that enable reduced system complexity. Recent results from the high energy battery and regenerative fuel cell technology development efforts will be presented. The technical approach, the key performance parameters and the technical results achieved to date in each of these new elements will be included. The Advanced Space Power Systems Project is part of the Game Changing Development Program under NASAs Space Technology Mission Directorate.

  17. Advanced launch system. Advanced development oxidizer turbopump program

    NASA Astrophysics Data System (ADS)

    1993-10-01

    On May 19, 1989, Pratt & Whitney was awarded contract NAS8-37595 by the National Aeronautics and Space Administration, Marshall Space Flight Center, Huntsville Alabama for an Advanced Development Program (ADP) to design, develop and demonstrate a highly reliable low cost, liquid oxygen turbopump for the Advanced Launch System (ALS). The ALS had an overall goal of reducing the cost of placing payloads in orbit by an order of magnitude. This goal would require a substantial reduction in life cycle costs, with emphasis on recurring costs, compared to current launch vehicles. Engine studies supporting these efforts were made for the Space Transportation Main Engine (STME). The emphasis on low cost required design simplification of components and subsystems such that the ground maintenance and test operations was minimized. The results of the Oxygen Turbopump ADP technology effort would provide data to be used in the STME. Initially the STME baseline was a gas generator cycle engine with a vacuum thrust level of 580,000 lbf. This was later increased to 650,000 lbf and the oxygen turbopump design approach was changed to reflect the new thrust level. It was intended that this ADP program be conducted in two phases. Phase 1, a basic phase, would encompass the preliminary design effort, and Phase II, an optional contract phase to cover design, fabrication and test evaluation of an oxygen turbopump at a component test facility at the NASA John C. Stennis Space Center in Mississippi. The basic phase included preliminary design and analysis, evaluation of low cost concepts, and evaluation of fabrication techniques. The option phase included design of the pump and support hardware, analysis of the final configuration to ensure design integrity, fabrication of hardware to demonstrate low cost, DVS Testing of hardware to verify the design, assembly of the turbopump and full scale turbopump testing. In December 1990, the intent of this ADP to support the design and development was

  18. Advanced launch system. Advanced development oxidizer turbopump program

    NASA Technical Reports Server (NTRS)

    1993-01-01

    On May 19, 1989, Pratt & Whitney was awarded contract NAS8-37595 by the National Aeronautics and Space Administration, Marshall Space Flight Center, Huntsville Alabama for an Advanced Development Program (ADP) to design, develop and demonstrate a highly reliable low cost, liquid oxygen turbopump for the Advanced Launch System (ALS). The ALS had an overall goal of reducing the cost of placing payloads in orbit by an order of magnitude. This goal would require a substantial reduction in life cycle costs, with emphasis on recurring costs, compared to current launch vehicles. Engine studies supporting these efforts were made for the Space Transportation Main Engine (STME). The emphasis on low cost required design simplification of components and subsystems such that the ground maintenance and test operations was minimized. The results of the Oxygen Turbopump ADP technology effort would provide data to be used in the STME. Initially the STME baseline was a gas generator cycle engine with a vacuum thrust level of 580,000 lbf. This was later increased to 650,000 lbf and the oxygen turbopump design approach was changed to reflect the new thrust level. It was intended that this ADP program be conducted in two phases. Phase 1, a basic phase, would encompass the preliminary design effort, and Phase II, an optional contract phase to cover design, fabrication and test evaluation of an oxygen turbopump at a component test facility at the NASA John C. Stennis Space Center in Mississippi. The basic phase included preliminary design and analysis, evaluation of low cost concepts, and evaluation of fabrication techniques. The option phase included design of the pump and support hardware, analysis of the final configuration to ensure design integrity, fabrication of hardware to demonstrate low cost, DVS Testing of hardware to verify the design, assembly of the turbopump and full scale turbopump testing. In December 1990, the intent of this ADP to support the design and development was

  19. Advanced information processing system for advanced launch system: Avionics architecture synthesis

    NASA Technical Reports Server (NTRS)

    Lala, Jaynarayan H.; Harper, Richard E.; Jaskowiak, Kenneth R.; Rosch, Gene; Alger, Linda S.; Schor, Andrei L.

    1991-01-01

    The Advanced Information Processing System (AIPS) is a fault-tolerant distributed computer system architecture that was developed to meet the real time computational needs of advanced aerospace vehicles. One such vehicle is the Advanced Launch System (ALS) being developed jointly by NASA and the Department of Defense to launch heavy payloads into low earth orbit at one tenth the cost (per pound of payload) of the current launch vehicles. An avionics architecture that utilizes the AIPS hardware and software building blocks was synthesized for ALS. The AIPS for ALS architecture synthesis process starting with the ALS mission requirements and ending with an analysis of the candidate ALS avionics architecture is described.

  20. Role of excipients and polymeric advancements in preparation of floating drug delivery systems

    PubMed Central

    Kaushik, Avinash Y; Tiwari, Ajay K; Gaur, Ajay

    2015-01-01

    Since decade or two, the development of floating drug delivery systems becomes a significant and novel tool as having low density than gastric content. There are various advanced polymers including chitosan, eudragit, etc., and excipients such as; pore forming agent, surfactants, etc. All of them are discussed briefly, and results are concluded from various reputed researches. We have discussed all natural and synthetic systems with their effect on the release and other parameters which are essential for the floating formulation development. PMID:25599027

  1. Advances in hypersonic vehicle synthesis with application to studies of advanced thermal protection system

    NASA Technical Reports Server (NTRS)

    Ardema, Mark D.

    1995-01-01

    This report summarizes the work entitled 'Advances in Hypersonic Vehicle Synthesis with Application to Studies of Advanced Thermal Protection Systems.' The effort was in two areas: (1) development of advanced methods of trajectory and propulsion system optimization; and (2) development of advanced methods of structural weight estimation. The majority of the effort was spent in the trajectory area.

  2. Electronic spark advance-type ignition system

    SciTech Connect

    Koike, H.

    1986-12-09

    An electronic spark advance-type ignition system is described for an internal combustion engine comprising: an ignition coil; a magnetic pickup for generating a pair of pulse signals with a time interval therebetween substantially corresponding to a maximum advance angle in terms of crankshaft rotation degrees for each rotation of a crankshaft of the engine; signal generating means responsive to the pair of pulse signals for the pickup for generating a pair of comparison signals of different levels within each of the crankshaft rotation degrees of the maximum advance angle and the other crankshaft rotation degrees; and control means for comparing the signal levels of each of the pairs of comparison signals to generate an energization starting position signal and an ignition timing determining ignition position signal for the ignition coil, the signal generating means including means for controlling the waveform of one of the pair of comparison signals so that the ignition position signal is advanced in angle with respect to the energization starting position signal. The energization starting position signal is generated under all conditions prior to the timing of generation of the earlier one of the next pair of pulse signals generated from the pickup. The ignition position signal is generated within the maximum advance angle at a point in time following generation of the earlier one of the next pair of pulse signals by at least a predetermined amount.

  3. EPR spin probe study of polymer associative systems.

    PubMed

    Wasserman, A M; Yasina, L L; Motyakin, M V; Aliev, I I; Churochkina, N A; Rogovina, L Z; Lysenko, E A; Baranovsky, V Yu

    2008-05-01

    Molecular dynamics of polyacrylamide gels, polymeric micelles and hydrogel of polyacrylic acid and macrodiisocyanate was investigated by the ESR spectroscopy of spin probes. The local mobility in network junction of polyacrylamide gels is found to be essentially slower than that in the micelles created by the low molecular weight detergents and does not depend on the amount and length of hydrophobic groups (C9 or C12) in the polymer chain. The immersion of 10-30 mol.% of ionic monomers into the polymer chain (sodium acrylate) influences insufficiently on the local mobility of network junctions. In aqueous solutions, polystyrene-block-poly-(N-ethyl-4-vinylpyridinium bromide) block copolymers create polymeric micelles. The local mobility in the polystyrene core of the micelles is about twice as much as that in the solid polystyrene. Partially swellable polymer network in aqueous solutions was synthesized from polyacrylic acid and macrodiisocyanate. The local mobility in hydrophobic regions of the gel is substantially lower than that in the hydrophilic regions. It was concluded that the hydrophobic and hydrophilic regions and the local dynamics of them dictate practical application of the polymer associative systems. PMID:17988940

  4. EPR spin probe study of polymer associative systems

    NASA Astrophysics Data System (ADS)

    Wasserman, A. M.; Yasina, L. L.; Motyakin, M. V.; Aliev, I. I.; Churochkina, N. A.; Rogovina, L. Z.; Lysenko, E. A.; Baranovsky, V. Yu.

    2008-05-01

    Molecular dynamics of polyacrilamide gels, polymeric micelles and hydrogel of polyacrylic acid and macrodiisocyanate was investigated by the ESR spectroscopy of spin probes. The local mobility in network junction of polyacrylamide gels is found to be essentially slower than that in the micelles created by the low molecular weight detergents and does not depend on the amount and length of hydrophobic groups (C9 or C12) in the polymer chain. The immersion of 10-30 mol.% of ionic monomers into the polymer chain (sodium acrylate) influences insufficiently on the local mobility of network junctions. In aqueous solutions, polystyrene-block-poly-( N-ethyl-4-vinylpyridinium bromide) block copolymers create polymeric micelles. The local mobility in the polystyrene core of the micelles is about twice as much as that in the solid polystyrene. Partially swellable polymer network in aqueous solutions was synthesized from polyacrylic acid and macrodiisocyanate. The local mobility in hydrophobic regions of the gel is substantially lower than that in the hydrophilic regions. It was concluded that the hydrophobic and hydrophilic regions and the local dynamics of them dictate practical application of the polymer associative systems.

  5. Advanced Technology System Scheduling Governance Model

    SciTech Connect

    Ang, Jim; Carnes, Brian; Hoang, Thuc; Vigil, Manuel

    2015-06-11

    In the fall of 2005, the Advanced Simulation and Computing (ASC) Program appointed a team to formulate a governance model for allocating resources and scheduling the stockpile stewardship workload on ASC capability systems. This update to the original document takes into account the new technical challenges and roles for advanced technology (AT) systems and the new ASC Program workload categories that must be supported. The goal of this updated model is to effectively allocate and schedule AT computing resources among all three National Nuclear Security Administration (NNSA) laboratories for weapons deliverables that merit priority on this class of resource. The process outlined below describes how proposed work can be evaluated and approved for resource allocations while preserving high effective utilization of the systems. This approach will provide the broadest possible benefit to the Stockpile Stewardship Program (SSP).

  6. Advanced turbine blade tip seal system

    NASA Technical Reports Server (NTRS)

    Zelahy, J. W.

    1981-01-01

    An advanced blade/shroud system designed to maintain close clearance between blade tips and turbine shrouds and at the same time, be resistant to environmental effects including high temperature oxidation, hot corrosion, and thermal cycling is described. Increased efficiency and increased blade life are attained by using the advanced blade tip seal system. Features of the system include improved clearance control when blade tips preferentially wear the shrouds and a superior single crystal superalloy tip. The tip design, joint location, characterization of the single crystal tip alloy, the abrasive tip treatment, and the component and engine test are among the factors addressed. Results of wear testing, quality control plans, and the total manufacturing cycle required to fully process the blades are also discussed.

  7. Advanced Active Thermal Control Systems Architecture Study

    NASA Technical Reports Server (NTRS)

    Hanford, Anthony J.; Ewert, Michael K.

    1996-01-01

    The Johnson Space Center (JSC) initiated a dynamic study to determine possible improvements available through advanced technologies (not used on previous or current human vehicles), identify promising development initiatives for advanced active thermal control systems (ATCS's), and help prioritize funding and personnel distribution among many research projects by providing a common basis to compare several diverse technologies. Some technologies included were two-phase thermal control systems, light-weight radiators, phase-change thermal storage, rotary fluid coupler, and heat pumps. JSC designed the study to estimate potential benefits from these various proposed and under-development thermal control technologies for five possible human missions early in the next century. The study compared all the technologies to a baseline mission using mass as a basis. Each baseline mission assumed an internal thermal control system; an external thermal control system; and aluminum, flow-through radiators. Solar vapor compression heat pumps and light-weight radiators showed the greatest promise as general advanced thermal technologies which can be applied across a range of missions. This initial study identified several other promising ATCS technologies which offer mass savings and other savings compared to traditional thermal control systems. Because the study format compares various architectures with a commonly defined baseline, it is versatile and expandable, and is expected to be updated as needed.

  8. Smart Materials for Advanced Applications: Self-Decontaminating Polymers, Photofunctional Composites, and Electroconductive Fibers

    NASA Astrophysics Data System (ADS)

    Little, Brian Kevin

    2011-12-01

    Materials capable of providing multifunctional properties controllable by some external stimulus (pH, light, temperature, etc) are highly desirable and obtainable given recent advancements in material science. Development of these so called "Smart" materials spanned across many disciplines of science with applications in industrial areas such as medical, military, security, and environmental. Furthermore, next-generation materials require the ability to not only sense/respond to changes in their external/internal environment, but process information in regards to these changes and adapt accordingly in a dynamic fashion, autonomously, so called "Intelligent" materials. Findings reported in this manuscript detail the synthesis, characterization, and application of smart materials in the following three areas: (1) self-cleaning polymers (2) photoresponsive composites and (3) electroconductive fibers. Self-Cleaning Polymers: Self-decontaminating polymers are unique materials capable of degrading toxic organic chemicals (TOCs). Barriers composed of or coated with our photochemical reactive polymer matrix could be applied to multiple surfaces for defense against TOCs; for example, military garments for protection against chemical warfare agents. This study investigates conditions necessary for formation of peroxides via O2 reduction induced by long-lived, strongly reducing benzophenyl ketyl (BPK) polymer radicals. Photolysis of aqueous solutions composed of sulphonated poly(ether etherketone), SPEEK, and poly(vinyl alcohol), PVA lead to the formation of the BPK radicals. Experiments investigate the formation and decomposition of peroxides in aqueous solutions of SPEEK/PVA under photolysis. Photofunctional Composites: Photoresponsive nanoporous (PN) films and powders were studied and evaluated as possible additives to sensitize the initiation of CH3NO2 via a mechanism involving coalescence of reaction sites. Such materials consist of a 3-D mesoporous silica framework

  9. Advanced Turbine Systems Program industrial system concept development

    SciTech Connect

    Gates, S.

    1995-10-01

    The objective of Phase II of the Advanced Turbine Systems Program is to develop conceptual designs of gas fired advanced turbine systems that can be adapted for operation on coal and biomass fuels. The technical, economic, and environmental performance operating on natural gas and in a coal fueled mode is to be assessed. Detailed designs and test work relating to critical components are to be completed and a market study is to be conducted.

  10. High-temperature polymer matrix composites

    NASA Technical Reports Server (NTRS)

    Meador, Michael A.

    1990-01-01

    Polymers research at the NASA Lewis Research Center has produced high-temperature, easily processable resin systems, such as PMR-15. In addition, the Polymers Branch has investigated ways to improve the mechanical properties of polymers and the microcracking resistance of polymer matrix composites in response to industry need for new and improved aeropropulsion materials. Current and future research in the Polymers Branch is aimed at advancing the upper use temperature of polymer matrix composites to 700 F and beyond by developing new resins, by examining the use of fiber reinforcements other than graphite, and by developing coatings for polymer matrix composites to increase their oxidation resistance.

  11. Advanced Biotelemetry Systems for Space Life Sciences

    NASA Technical Reports Server (NTRS)

    Hines, John W.; Connolly, John P. (Technical Monitor)

    1994-01-01

    The Sensors 2000! Program at NASA-Ames Research Center is developing an Advanced Biotelemetry System (ABTS) for Space Life Sciences applications. This modular suite of instrumentation is planned to be used in operational spaceflight missions, ground-based research and development experiments, and collaborative, technology transfer and commercialization activities. The measured signals will be transmitted via radio-frequency (RF), electromagnetic or optical carriers and direct-connected leads to a remote ABTS receiver and data acquisition system for data display, storage, and transmission to Earth. Intermediate monitoring and display systems may be hand held or portable, and will allow for personalized acquisition and control of medical and physiological data.

  12. Modal testing of advanced wind turbine systems

    SciTech Connect

    Osgood, R.M.

    1995-09-01

    The US Department of Energy (DOE), in conjunction with the US wind industry, is supporting the development of technology for advanced, higher efficiency wind energy conversion systems. Under the Advanced Wind Turbine (AAWT) Program, the DOE, through the National Renewable Energy Laboratory (NREL), will assist US industry in incorporating advanced wind turbine technology into utility-grade wind turbines. As part of the AWT Program, NREL is conducting a range of activities aimed at assisting the wind industry with system design analysis and testing. One major activity is NREL`s Full System Model Testing (FSMT) task. In 1993 and 1994, NREL`s FSMT team conducted model surveys on several wind turbine systems developed by industry, including Atlantic Orient Corporation`s AOC 15/50, R. Lynette and Associates` AWT-26 P1, and Carter Wind Turbines Incorporated`s CWT-300. This paper describes how these model surveys were carried out and how industry and NREL wind researchers used the experimental results to validate their analytical models.

  13. Advanced information processing system for advanced launch system: Hardware technology survey and projections

    NASA Technical Reports Server (NTRS)

    Cole, Richard

    1991-01-01

    The major goals of this effort are as follows: (1) to examine technology insertion options to optimize Advanced Information Processing System (AIPS) performance in the Advanced Launch System (ALS) environment; (2) to examine the AIPS concepts to ensure that valuable new technologies are not excluded from the AIPS/ALS implementations; (3) to examine advanced microprocessors applicable to AIPS/ALS, (4) to examine radiation hardening technologies applicable to AIPS/ALS; (5) to reach conclusions on AIPS hardware building blocks implementation technologies; and (6) reach conclusions on appropriate architectural improvements. The hardware building blocks are the Fault-Tolerant Processor, the Input/Output Sequencers (IOS), and the Intercomputer Interface Sequencers (ICIS).

  14. Health requirements for advanced coal extraction systems

    NASA Technical Reports Server (NTRS)

    Zimmerman, W. F.

    1980-01-01

    Health requirements were developed as long range goals for future advanced coal extraction systems which would be introduced into the market in the year 2000. The goal of the requirements is that underground coal miners work in an environment that is as close as possible to the working conditions of the general population, that they do not exceed mortality and morbidity rates resulting from lung diseases that are comparable to those of the general population, and that their working conditions comply as closely as possible to those of other industries as specified by OSHA regulations. A brief technique for evaluating whether proposed advanced systems meet these safety requirements is presented, as well as a discussion of the costs of respiratory disability compensation.

  15. Development of advanced fuel cell system

    NASA Technical Reports Server (NTRS)

    Gitlow, B.; Meyer, A. P.; Bell, W. F.; Martin, R. E.

    1978-01-01

    An experimental program was conducted continuing the development effort to improve the weight, life, and performance characteristics of hydrogen-oxygen alkaline fuel cells for advanced power systems. These advanced technology cells operate with passive water removal which contributes to a lower system weight and extended operating life. Endurance evaluation of two single cells and two, two-cell plaques was continued. Three new test articles were fabricated and tested. A single cell completed 7038 hours of endurance testing. This cell incorporated a Fybex matrix, hybrid-frame, PPF anode, and a 90 Au/10 Pt cathode. This configuration was developed to extend cell life. Two cell plaques with dedicated flow fields and manifolds for all fluids did not exhibit the cell-to-cell electrolyte transfer that limited the operating life of earlier multicell plaques.

  16. Advances in Structures for Large Space Systems

    NASA Technical Reports Server (NTRS)

    Belvin, W. Keith

    2004-01-01

    The development of structural systems for scientific remote sensing and space exploration has been underway for four decades. The seminal work from 1960 to 1980 provided the basis for many of the design principles of modern space systems. From 1980- 2000 advances in active materials and structures and the maturing of composites technology led to high precision active systems such those used in the Space Interferometry Mission. Recently, thin-film membrane or gossamer structures are being investigated for use in large area space systems because of their low mass and high packaging efficiency. Various classes of Large Space Systems (LSS) are defined in order to describe the goals and system challenges in structures and materials technologies. With an appreciation of both past and current technology developments, future technology challenges are used to develop a list of technology investments that can have significant impacts on LSS development.

  17. NASDA's Advanced On-Line System (ADOLIS)

    NASA Technical Reports Server (NTRS)

    Yamamoto, Yoshikatsu; Hara, Hideo; Yamada, Shigeo; Hirata, Nobuyuki; Komatsu, Shigenori; Nishihata, Seiji; Oniyama, Akio

    1993-01-01

    Spacecraft operations including ground system operations are generally realized by various large or small scale group work which is done by operators, engineers, managers, users and so on, and their positions are geographically distributed in many cases. In face-to-face work environments, it is easy for them to understand each other. However, in distributed work environments which need communication media, if only using audio, they become estranged from each other and lose interest in and continuity of work. It is an obstacle to smooth operation of spacecraft. NASDA has developed an experimental model of a new real-time operation control system called 'ADOLIS' (ADvanced On-Line System) adopted to such a distributed environment using a multi-media system dealing with character, figure, image, handwriting, video and audio information which is accommodated to operation systems of a wide range including spacecraft and ground systems. This paper describes the results of the development of the experimental model.

  18. Multifunctional Delivery Systems for Advanced oral Uptake of Peptide/Protein Drugs.

    PubMed

    Park, Jin Woo; Kim, Sun Jin; Kwag, Dong Sup; Kim, Sol; Park, Jeyoung; Youn, Yu Seok; Bae, You Han; Lee, Eun Seong

    2015-01-01

    In recent years, advances in biotechnology and protein engineering have enabled the production of large quantities of proteins and peptides as important therapeutic agents. Various researchers have used biocompatible functional polymers to prepare oral dosage forms of proteins and peptides for chronic use and for easier administration to enhance patient compliance. However, there is a need to enhance their safety and effectiveness further. Most macromolecules undergo severe denaturation at low pH and enzymatic degradation in the gastrointestinal tract. The macromolecules' large molecular size and low lipophilicity cause low permeation through the intestinal membrane. The major strategies that have been used to overcome these challenges (in oral drug carrier systems) can be classified as follows: enteric coating or encapsulation with pH-sensitive polymers or mucoadhesive polymers, co-administration of protease inhibitors, incorporation of absorption enhancers, modification of the physicochemical properties of the macromolecules, and site-specific delivery to the colon. This review attempts to summarize the various advanced oral delivery carriers, including nanoparticles, lipid carriers, such as liposomes, nano-aggregates using amphiphilic polymers, complex coacervation of oppositely charged polyelectrolytes, and inorganic porous particles. The particles were formulated and/or surface modified with functional polysaccharides or synthetic polymers to improve oral bioavailability of proteins and peptides. We also discuss formulation strategies to overcome barriers, therapeutic efficacies in vivo, and potential benefits and issues for successful oral dosage forms of the proteins and peptides. PMID:26027575

  19. Systems Engineering Building Advances Power Grid Research

    SciTech Connect

    Virden, Jud; Huang, Henry; Skare, Paul; Dagle, Jeff; Imhoff, Carl; Stoustrup, Jakob; Melton, Ron; Stiles, Dennis; Pratt, Rob

    2015-08-19

    Researchers and industry are now better equipped to tackle the nation’s most pressing energy challenges through PNNL’s new Systems Engineering Building – including challenges in grid modernization, buildings efficiency and renewable energy integration. This lab links real-time grid data, software platforms, specialized laboratories and advanced computing resources for the design and demonstration of new tools to modernize the grid and increase buildings energy efficiency.

  20. Viscosity of the oil-in-water Pickering emulsion stabilized by surfactant-polymer and nanoparticle-surfactant-polymer system

    NASA Astrophysics Data System (ADS)

    Sharma, Tushar; Kumar, G. Suresh; Chon, Bo Hyun; Sangwai, Jitendra S.

    2014-11-01

    Information on the viscosity of Pickering emulsion is required for their successful application in upstream oil and gas industry to understand their stability at extreme environment. In this work, a novel formulation of oil-in-water (o/w) Pickering emulsion stabilized using nanoparticle-surfactant-polymer (polyacrylamide) system as formulated in our earlier work (Sharma et al., Journal of Industrial and Engineering Chemistry, 2014) is investigated for rheological stability at high pressure and high temperature (HPHT) conditions using a controlled-strain rheometer. The nanoparticle (SiO2 and clay) concentration is varied from 1.0 to 5.0 wt%. The results are compared with the rheological behavior of simple o/w emulsion stabilized by surfactant-polymer system. Both the emulsions exhibit non-Newtonian shear thinning behavior. A positive shift in this behavior is observed for surfactant-polymer stabilized emulsion at high pressure conditions. Yield stress is observed to increase with pressure for surfactant-polymer emulsion. In addition, increase in temperature has an adverse effect on the viscosity of emulsion stabilized by surfactant-polymer system. In case of nanoparticle-surfactant-polymer stabilized o/w emulsion system, the viscosity and yield stress are predominantly constant for varying pressure and temperature conditions. The viscosity data for both o/w emulsion systems are fitted by the Herschel-Bulkley model and found to be satisfactory. In general, the study indicates that the Pickering emulsion stabilized by nanoparticle-surfactant-polymer system shows improved and stable rheological properties as compared to conventional emulsion stabilized by surfactant-polymer system indicating their successful application for HPHT environment in upstream oil and gas industry.

  1. Recent advances in superhydrophobic nanomaterials and nanoscale systems.

    PubMed

    Nagappan, Saravanan; Park, Sung Soo; Ha, Chang-Sik

    2014-02-01

    This review describes the recent advances in the field of superhydrophobic nanomaterials and nanoscale systems. The term superhydrophobic is defined from the surface properties when the surface shows the contact angle (CA) higher than 150 degrees. This could be well known from the lotus effect due to the non-stick and self-cleaning properties of the lotus leaf (LL). We briefly introduced the methods of preparing superhydrophobic surfaces using top-down approaches, bottom-up approaches and a combination of top-down and bottom-up approaches and various ways to prepare superhydrophobic nanomaterials and nanoscale systems using the bio-inspired materials, polymer nanocomposites, metal nanoparticles graphene oxide (GO) and carbon nanotubes (CNTs). We also pointed out the recent applications of the superhydrophobic nanomaterials and nanoscale systems in oil-spill capture and separations, self-cleaning and self-healing systems, bio-medicals, anti-icing and anti-corrosive, electronics, catalysis, textile fabrics and papers etc. The review also highlights the visionary outlook for the future development and use of the superhydrophobic nanomaterials and nanoscale systems for a wide variety of applications. PMID:24749434

  2. Systems engineering and integration: Advanced avionics laboratories

    NASA Technical Reports Server (NTRS)

    1990-01-01

    In order to develop the new generation of avionics which will be necessary for upcoming programs such as the Lunar/Mars Initiative, Advanced Launch System, and the National Aerospace Plane, new Advanced Avionics Laboratories are required. To minimize costs and maximize benefits, these laboratories should be capable of supporting multiple avionics development efforts at a single location, and should be of a common design to support and encourage data sharing. Recent technological advances provide the capability of letting the designer or analyst perform simulations and testing in an environment similar to his engineering environment and these features should be incorporated into the new laboratories. Existing and emerging hardware and software standards must be incorporated wherever possible to provide additional cost savings and compatibility. Special care must be taken to design the laboratories such that real-time hardware-in-the-loop performance is not sacrificed in the pursuit of these goals. A special program-independent funding source should be identified for the development of Advanced Avionics Laboratories as resources supporting a wide range of upcoming NASA programs.

  3. Advanced laser systems for photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Klosner, Marc; Sampathkumar, Ashwin; Chan, Gary; Wu, Chunbai; Gross, Daniel; Heller, Donald F.

    2015-03-01

    We describe the ongoing development of laser systems for advanced photoacoustic imaging (PAI). We discuss the characteristics of these laser systems and their particular benefits for soft tissue imaging and next-generation breast cancer diagnostics. We provide an overview of laser performance and compare this with other laser systems that have been used for early-stage development of PAI. These advanced systems feature higher pulse energy output at clinically relevant repetition rates, as well as a novel wavelength-cycling output pulse format. Wavelength cycling provides pulse sequences for which the output repeatedly alternates between two wavelengths that provide differential imaging. This capability improves co-registration of captured differential images. We present imaging results of phantoms obtained with a commercial ultrasound detector system and a wavelength-cycling laser source providing ~500 mJ/pulse at 755 and 797 nm, operating at 25 Hz. The results include photoacoustic images and corresponding pulse-echo data from a tissue mimicking phantom containing inclusions, simulating tumors in the breast. We discuss the application of these systems to the contrast-enhanced detection of various tissue types and tumors.

  4. Polymer-surfactant systems in bulk and at fluid interfaces.

    PubMed

    Guzmán, Eduardo; Llamas, Sara; Maestro, Armando; Fernández-Peña, Laura; Akanno, Andrew; Miller, Reinhard; Ortega, Francisco; Rubio, Ramón G

    2016-07-01

    The interest of polymer-surfactant systems has undergone a spectacular development in the last thirty years due to their complex behavior and their importance in different industrial sectors. The importance can be mainly associated with the rich phase behavior of these mixtures that confers a wide range of physico-chemical properties to the complexes formed by polymers and surfactants, both in bulk and at the interfaces. This latter aspect is especially relevant because of the use of their mixture for the stabilization of dispersed systems such as foams and emulsions, with an increasing interest in several fields such as cosmetic, food science or fabrication of controlled drug delivery structures. This review presents a comprehensive analysis of different aspects related to the phase behavior of these mixtures and their intriguing behavior after adsorption at the liquid/air interface. A discussion of some physical properties of the bulk is also included. The discussion clearly points out that much more work is needed for obtaining the necessary insights for designing polymer-surfactant mixtures for specific applications. PMID:26608684

  5. Processing of Polymer Nanofibers Through Electrospinning as Drug Delivery Systems

    NASA Astrophysics Data System (ADS)

    Kenawy, E.; Abdel-Hay, F. I.; El-Newehy, M. H.; Wnek, G. E.

    The use of electrospun fibers as drug carriers could be promising in the future for biomedical applications, especially postoperative local chemotherapy. In this research, electrospun fibers were developed as a new system for the delivery of ketoprofen as non-steroidal anti-inflammatory drug (NSAID). The fibers were made either from polycaprolactone (PCL) as a biodegradable polymer or polyurethane (PU) as a non-biodegradable polymer, or from the blends of the two. The release of the ketoprofen was followed by UV—VIS spectroscopy in phosphate buffer of pH 7.4 at 37°C and 20°C. The results showed that the release rates from the polycaprolactone, polyurethane and their blend were similar. However, the blend of the polycaprolactone with polyurethane improved its visual mechanical properties. Release profiles from the electrospun mats were compared to cast films of the various formulations.

  6. From precision polymers to complex materials and systems

    NASA Astrophysics Data System (ADS)

    Lutz, Jean-François; Lehn, Jean-Marie; Meijer, E. W.; Matyjaszewski, Krzysztof

    2016-05-01

    Complex chemical systems, such as living biological matter, are highly organized structures based on discrete molecules in constant dynamic interactions. These natural materials can evolve and adapt to their environment. By contrast, man-made materials exhibit simpler properties. In this Review, we highlight that most of the necessary elements for the development of more complex synthetic matter are available today. Using modern strategies, such as controlled radical polymerizations, supramolecular polymerizations or stepwise synthesis, polymers with precisely controlled molecular structures can be synthesized. Moreover, such tailored polymers can be folded or self-assembled into defined nanoscale morphologies. These self-organized macromolecular objects can be at thermal equilibrium or can be driven out of equilibrium. Recently, in the latter case, interesting dynamic materials have been developed. However, this is just a start, and more complex adaptive materials are anticipated.

  7. Novel patternable and conducting metal-polymer nanocomposites: a step towards advanced mutlifunctional materials

    NASA Astrophysics Data System (ADS)

    Rodríguez-Cantó, Pedro J.; Martínez-Marco, Mariluz; Abargues, Rafael; Latorre-Garrido, Victor; Martínez-Pastor, Juan P.

    2013-03-01

    In this work, we present a novel patternable conducting nanocomposite containing gold nanoparticles. Here, the in-situ polymerization of 3T is carried out using HAuCl4 as oxidizing agent inside PMMA as host matrix. During the bake step, the gold salt is also reduced from Au(III) to Au(0) generating Au nanoparticles in the interpenetrating polymer network (IPN) system. We found that this novel multifunctional resist shows electrical conductivity and plasmonic properties as well as potential patterning capability provided by the host matrix. The resulting nanocomposite has been investigated by TEM and UV-Vis spectroscopy. Electrical characterization was also conducted for different concentration of 3T and Au(III) following a characteristic percolation behaviour. Conductivities values from 10-5 to 10 S/cm were successfully obtained depending on the IPN formulation. Moreover, The Au nanoparticles generated exhibited a localized surface plasmon resonance at around 520 nm. This synthetic approach is of potential application to modify the conductivity of numerous insulating polymers and synthesize Au nanoparticles preserving to some extent their physical and chemical properties. In addition, combination of optical properties (Plasmonics), electrical, and lithographic capability in the same material allows for the design of materials with novel functionalities and provides the basis for next generation devices.

  8. Airborne Advanced Reconfigurable Computer System (ARCS)

    NASA Technical Reports Server (NTRS)

    Bjurman, B. E.; Jenkins, G. M.; Masreliez, C. J.; Mcclellan, K. L.; Templeman, J. E.

    1976-01-01

    A digital computer subsystem fault-tolerant concept was defined, and the potential benefits and costs of such a subsystem were assessed when used as the central element of a new transport's flight control system. The derived advanced reconfigurable computer system (ARCS) is a triple-redundant computer subsystem that automatically reconfigures, under multiple fault conditions, from triplex to duplex to simplex operation, with redundancy recovery if the fault condition is transient. The study included criteria development covering factors at the aircraft's operation level that would influence the design of a fault-tolerant system for commercial airline use. A new reliability analysis tool was developed for evaluating redundant, fault-tolerant system availability and survivability; and a stringent digital system software design methodology was used to achieve design/implementation visibility.

  9. Advanced laser stratospheric monitoring systems analyses

    NASA Technical Reports Server (NTRS)

    Larsen, J. C.

    1984-01-01

    This report describes the software support supplied by Systems and Applied Sciences Corporation for the study of Advanced Laser Stratospheric Monitoring Systems Analyses under contract No. NAS1-15806. This report discusses improvements to the Langley spectroscopic data base, development of LHS instrument control software and data analyses and validation software. The effect of diurnal variations on the retrieved concentrations of NO, NO2 and C L O from a space and balloon borne measurement platform are discussed along with the selection of optimum IF channels for sensing stratospheric species from space.

  10. Rotorcraft Digital Advanced Avionics System (rodaas)

    NASA Technical Reports Server (NTRS)

    Taira, B.

    1985-01-01

    A simulator is being built to determine the practicality of using an advanced avionics system in a helicopter. Features include an autopilot; a navigation and flight planning component; an advisory system built into the computer; conventional gages and displays; a clock function; a fuel totalizer; a weight and balance computator; a performance evaluator; and emergency and normal checklists. The translation of a computer program written in PASCAL into a form that can be read by the graphics package for the simulator and basic electronic work in simulator construction are discussed.

  11. Polymers for hydrogen infrastructure and vehicle fuel systems : applications, properties, and gap analysis.

    SciTech Connect

    Barth, Rachel Reina; Simmons, Kevin L.; San Marchi, Christopher W.

    2013-10-01

    This document addresses polymer materials for use in hydrogen service. Section 1 summarizes the applications of polymers in hydrogen infrastructure and vehicle fuel systems and identifies polymers used in these applications. Section 2 reviews the properties of polymer materials exposed to hydrogen and/or high-pressure environments, using information obtained from published, peer-reviewed literature. The effect of high pressure on physical and mechanical properties of polymers is emphasized in this section along with a summary of hydrogen transport through polymers. Section 3 identifies areas in which fuller characterization is needed in order to assess material suitability for hydrogen service.

  12. Advanced Life Support System Value Metric

    NASA Technical Reports Server (NTRS)

    Jones, Harry W.; Rasky, Daniel J. (Technical Monitor)

    1999-01-01

    The NASA Advanced Life Support (ALS) Program is required to provide a performance metric to measure its progress in system development. Extensive discussions within the ALS program have led to the following approach. The Equivalent System Mass (ESM) metric has been traditionally used and provides a good summary of the weight, size, and power cost factors of space life support equipment. But ESM assumes that all the systems being traded off exactly meet a fixed performance requirement, so that the value and benefit (readiness, performance, safety, etc.) of all the different systems designs are considered to be exactly equal. This is too simplistic. Actual system design concepts are selected using many cost and benefit factors and the system specification is defined after many trade-offs. The ALS program needs a multi-parameter metric including both the ESM and a System Value Metric (SVM). The SVM would include safety, maintainability, reliability, performance, use of cross cutting technology, and commercialization potential. Another major factor in system selection is technology readiness level (TRL), a familiar metric in ALS. The overall ALS system metric that is suggested is a benefit/cost ratio, SVM/[ESM + function (TRL)], with appropriate weighting and scaling. The total value is given by SVM. Cost is represented by higher ESM and lower TRL. The paper provides a detailed description and example application of a suggested System Value Metric and an overall ALS system metric.

  13. Interactions of complex polymers with nanoporous substrate.

    PubMed

    Ziebarth, Jesse D; Wang, Yongmei

    2016-06-28

    With the advance of polymer synthesis, polymers that possess unique architectures such as stars or cyclic chains, and unique chemical composition distributions such as block copolymers or statistical copolymers have become frequently encountered. Characterization of these complex polymer systems drives the development of interactive chromatography where the adsorption of polymers on the porous substrate in chromatography columns is finely tuned. Liquid Chromatography at the Critical Condition (LCCC) in particular makes use of the existence of the Critical Adsorption Point (CAP) of polymers on solid surfaces and has been successfully applied to characterization of complex polymer systems. Interpretation and understanding of chromatography behaviour of complex polymers in interactive chromatography motivates theoretical/computational studies on the CAP of polymers and partitioning of these complex polymers near the CAP. This review article covers the theoretical questions encountered in chromatographic studies of complex polymers. PMID:27263839

  14. Advanced airborne ISR demonstration system (USA)

    NASA Astrophysics Data System (ADS)

    Henry, Daniel J.

    2005-05-01

    Recon/Optical, Inc. (ROI) is developing an advanced airborne Intelligence, Surveillance, and Reconnaissance (ISR) demonstration system based upon the proven ROI technology used in the SHAred Reconnaissance Pod (SHARP) for the U.S. Navy F/A-18. The demonstration system, which includes several state-of-the-art technology enhancements for next-generation ISR, is scheduled for flight testing in the summer of 2005. The demonstration system contains a variant of the SHARP medium altitude CA-270 camera, comprising an inertially stabilized Visible/NIR 5Kx5K imager and MWIR 2Kx2K imager to provide simultaneous high resolution/wide area coverage dual-band operation. The imager has been upgraded to incorporate a LN-100G GPS/INS within the sensor passive isolation loop to improve the accuracy of the NITF image metadata. The Image Processor is also based upon the SHARP configuration, but the demo system contains several enhancements including increased image processing horsepower, Ethernet-based Command & Control, next-generation JPEG2000 image compression, JPEG2000 Interactive Protocol (JPIP) network data server/client architecture, bi-directional RF datalink, advanced image dissemination/exploitation, and optical Fibrechannel I/O to the solid state recorder. This paper describes the ISR demonstration system and identifies the new network centric CONOPS made possible by the technology enhancements.

  15. Advanced Autonomous Systems for Space Operations

    NASA Astrophysics Data System (ADS)

    Gross, A. R.; Smith, B. D.; Muscettola, N.; Barrett, A.; Mjolssness, E.; Clancy, D. J.

    2002-01-01

    New missions of exploration and space operations will require unprecedented levels of autonomy to successfully accomplish their objectives. Inherently high levels of complexity, cost, and communication distances will preclude the degree of human involvement common to current and previous space flight missions. With exponentially increasing capabilities of computer hardware and software, including networks and communication systems, a new balance of work is being developed between humans and machines. This new balance holds the promise of not only meeting the greatly increased space exploration requirements, but simultaneously dramatically reducing the design, development, test, and operating costs. New information technologies, which take advantage of knowledge-based software, model-based reasoning, and high performance computer systems, will enable the development of a new generation of design and development tools, schedulers, and vehicle and system health management capabilities. Such tools will provide a degree of machine intelligence and associated autonomy that has previously been unavailable. These capabilities are critical to the future of advanced space operations, since the science and operational requirements specified by such missions, as well as the budgetary constraints will limit the current practice of monitoring and controlling missions by a standing army of ground-based controllers. System autonomy capabilities have made great strides in recent years, for both ground and space flight applications. Autonomous systems have flown on advanced spacecraft, providing new levels of spacecraft capability and mission safety. Such on-board systems operate by utilizing model-based reasoning that provides the capability to work from high-level mission goals, while deriving the detailed system commands internally, rather than having to have such commands transmitted from Earth. This enables missions of such complexity and communication` distances as are not

  16. Distributed sensor coordination for advanced energy systems

    SciTech Connect

    Tumer, Kagan

    2015-03-12

    Motivation: The ability to collect key system level information is critical to the safe, efficient and reliable operation of advanced power systems. Recent advances in sensor technology have enabled some level of decision making directly at the sensor level. However, coordinating large numbers of sensors, particularly heterogeneous sensors, to achieve system level objectives such as predicting plant efficiency, reducing downtime or predicting outages requires sophisticated coordination algorithms. Indeed, a critical issue in such systems is how to ensure the interaction of a large number of heterogenous system components do not interfere with one another and lead to undesirable behavior. Objectives and Contributions: The long-term objective of this work is to provide sensor deployment, coordination and networking algorithms for large numbers of sensors to ensure the safe, reliable, and robust operation of advanced energy systems. Our two specific objectives are to: 1. Derive sensor performance metrics for heterogeneous sensor networks. 2. Demonstrate effectiveness, scalability and reconfigurability of heterogeneous sensor network in advanced power systems. The key technical contribution of this work is to push the coordination step to the design of the objective functions of the sensors, allowing networks of heterogeneous sensors to be controlled. By ensuring that the control and coordination is not specific to particular sensor hardware, this approach enables the design and operation of large heterogeneous sensor networks. In addition to the coordination coordination mechanism, this approach allows the system to be reconfigured in response to changing needs (e.g., sudden external events requiring new responses) or changing sensor network characteristics (e.g., sudden changes to plant condition). Impact: The impact of this work extends to a large class of problems relevant to the National Energy Technology Laboratory including sensor placement, heterogeneous sensor

  17. Polymer mud system maintains high ROP in deep well

    SciTech Connect

    Palm, J.D. )

    1994-10-24

    The use of a polymer mud system with low plastic viscosity helped reduce the drilling time on a deep well in Oklahoma. An aggressive bit program and the special mud system, which kept low-gravity solids to a minimum, kept the rate of penetration (ROP) high in the deeper sections of the well. The Montgomery No. 3-A well, located in section 3-6N-9W in Caddo County, Okla., reached total depth of 18,345 ft in 106 days for less than $1.6 million, which was quicker and less expensive than offset wells. The drilling of this well is detailed.

  18. Transient Interfacial Phenomena in Miscible Polymer Systems (TIPMPS)

    NASA Technical Reports Server (NTRS)

    Pojman, John A.; Bessonov, Nicholas; Volpert, Vitaly; Wilke, Hermann

    2003-01-01

    Almost one hundred years ago Korteweg published a theory of how stresses could be induced in miscible fluids by concentration gradients, causing phenomena that would appear to be the same as with immiscible fluids. Miscible fluids could manifest a transient or effective interfacial tension (EIT). To this day, there has been no definitive experiment to confirm Korteweg's model but numerous fascinating and suggestive experiments have been reported. The goal of TIPMPS is to answer the question: Can concentration and temperature gradients in miscible materials induce stresses that cause convection? Many polymer processes involving miscible monomer and polymer systems could be affected by fluid flow and so this work could help understand miscible polymer processing, not only in microgravity, but also on earth. Demonstrating the existence of this phenomenon in miscible fluids will open up a new area of study for materials science. The science objectives of TIPMPS are: (1) Determine if convection can be induced by variation of the width of a miscible interface; (2) Determine if convection can be induced by variation of temperature along a miscible interface; (3) Determine if convection can be induced by variation of conversion along a miscible interface An interface between two miscible fluids can best be created via a spatially-selective photopolymerization of dodecyl acrylate with a photoinitiator, which allows the creation of precise and accurate concentration gradients between polymer and monomer. Optical techniques will be used to measure the refractive index variation caused by the resultant temperature and concentration fields. The viscosity of the polymer will be measured from the increase in the fluorescence of pyrene. Because the large concentration and temperature gradients cause buoyancy-driven convection that prevents the observation of the predicted flows, the experiment must be done in microgravity. In this report, we will consider our efforts to estimate

  19. Gelled polymer systems for permeability modification in petroleum reservoirs

    SciTech Connect

    Willhite, G.P.; Green, D.W.; Thiele, J.L.; McCool, C.S.; Mertes, K.B.

    1991-09-01

    The research program described in this report was conducted to improve the performance and predictability of in situ gelation processes designed to increase volumetric sweep efficiency of fluid displacement processes. A principal objective of this research was to develop procedures for design and evaluation of permeability modification processes. Research was conducted in three broad areas: (1) Physical and Chemical Characterization of Gelling Systems (2) In situ Gelation and (3) Mathematical Modeling of In Site Gelation. Gelling systems used chromium as the crosslinking agent. Polyacrylamide and polysaccharides gelling systems were studied. Research was conducted on the chemical structure of polymer/metal ion complexes, kinetics of the reduction of Cr(6) to Cr(3) by thiourea, kinetics of oligomerization and uptake of chromium by polyacrylamide and rheology of chromium/polysaccharide gelling systems. Studies of polymer/metal ion complexes were conducted using solutions of pure monomer, dimer and trimer forms of chromium. A mathematical model was developed to examine the kinetics of Cr(3) oligomerization and uptake of chromium by polyacrylamide. Rheological studies were completed on chromium/polysaccharide gels. In situ gelation experiments were conducted using a bis-ethylenediamine chromium complex and chromium(3) polyacrylamide gelling systems in sandpacks. A numerical model of in situ gelation of chromium/polyacrylamide systems was developed for linear displacement in a sandpack. The numerical model is based on filtration mechanisms and is consistent with experimental data and models developed in this research program. 103 figs., 21 tabs.

  20. Advances in Primary Central Nervous System Lymphoma.

    PubMed

    Patrick, Lauren B; Mohile, Nimish A

    2015-12-01

    Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkin lymphoma that is limited to the CNS. Although novel imaging techniques aid in discriminating lymphoma from other brain tumors, definitive diagnosis requires brain biopsy, vitreoretinal biopsy, or cerebrospinal fluid analysis. Survival rates in clinical studies have improved over the past 20 years due to the addition of high-dose methotrexate-based chemotherapy regimens to whole-brain radiotherapy. Long-term survival, however, is complicated by clinically devastating delayed neurotoxicity. Newer regimens are attempting to reduce or eliminate radiotherapy from first-line treatment with chemotherapy dose intensification. Significant advances have also been made in the fields of pathobiology and treatment, with more targeted treatments on the horizon. The rarity of the disease makes conducting of prospective clinical trials challenging, requiring collaborative efforts between institutions. This review highlights recent advances in the biology, detection, and treatment of PCNSL in immunocompetent patients. PMID:26475775

  1. Status of solid polymer fuel cell system development

    NASA Astrophysics Data System (ADS)

    Shoesmith, J. P.; Collins, R. D.; Oakley, M. J.; Stevenson, D. K.

    1994-04-01

    Solid polymer fuel cell (SPFC) systems are expected to see service in a wide variety of applications, including road vehicles, trains, ships, undersea power, and small scale stationary power generation. Each application brings unique requirements in terms of fuel, power, efficiency, volume and weight and, consequently, SPFC systems are expected to take a variety of forms. This paper reviews the development issues which must be resolved before SPFC systems can enter commercial service. It includes the results of system studies completed by Rolls-Royce and Associates during the last two years. Development priorities are highlighted, particularly for the stack and fuel processing system. Results of the testing of a novel compact fuel processing system are presented.

  2. Novel mucoadhesion tests for polymers and polymer-coated particles to design optimal mucoadhesive drug delivery systems.

    PubMed

    Takeuchi, Hirofumi; Thongborisute, Jringjai; Matsui, Yuji; Sugihara, Hikaru; Yamamoto, Hiromitsu; Kawashima, Yoshiaki

    2005-11-01

    To design an effective particulate drug delivery system having mucoadhesive function, several mucoadhesion tests for polymers and the resultant particulate systems were developed. Mucin particle method is a simple mucoadhesion test for polymers, in which the commercial mucin particles are used. By measuring the change in particle size or zeta potential of the mucin particle in a certain concentration of polymer solution, we could estimate the extent of their mucoadhesive property. BIACORE method is also a novel mucoadhesion test for polymers. On passing through the mucin suspension on the polymer-immobilized chip of BIACORE instrument, the interaction was quantitatively evaluated with the change in its response diagram. By using these mucoadhesion tests, we detected a strong mucoadhesive property of several types of chitosan and Carbopol. Evaluation of mucoadhesive property of polymer-coated particulate systems was demonstrated with the particle counting method developed by us. To detect the mucoadhesive phenomena in the intestinal tract, we observed the rat intestine with the confocal laser scanning microscope (CLSM) after oral administration of the particulate systems. The resultant photographs clearly showed a longer retention of submicron-sized chitosan-coated liposomes (ssCS-Lip) in the intestinal tract than other liposomal particles tested such as non-coated liposomes and chitosan-coated multilamellar one. These observations explained well the superiority of the ssCS-Lip as drug carrier in oral administration of calcitonin in rats than other liposomal particles. PMID:16169120

  3. Advanced Life Support System Value Metric

    NASA Technical Reports Server (NTRS)

    Jones, Harry W.; Arnold, James O. (Technical Monitor)

    1999-01-01

    The NASA Advanced Life Support (ALS) Program is required to provide a performance metric to measure its progress in system development. Extensive discussions within the ALS program have reached a consensus. The Equivalent System Mass (ESM) metric has been traditionally used and provides a good summary of the weight, size, and power cost factors of space life support equipment. But ESM assumes that all the systems being traded off exactly meet a fixed performance requirement, so that the value and benefit (readiness, performance, safety, etc.) of all the different systems designs are exactly equal. This is too simplistic. Actual system design concepts are selected using many cost and benefit factors and the system specification is then set accordingly. The ALS program needs a multi-parameter metric including both the ESM and a System Value Metric (SVM). The SVM would include safety, maintainability, reliability, performance, use of cross cutting technology, and commercialization potential. Another major factor in system selection is technology readiness level (TRL), a familiar metric in ALS. The overall ALS system metric that is suggested is a benefit/cost ratio, [SVM + TRL]/ESM, with appropriate weighting and scaling. The total value is the sum of SVM and TRL. Cost is represented by ESM. The paper provides a detailed description and example application of the suggested System Value Metric.

  4. Demonstration Advanced Avionics System (DAAS) function description

    NASA Technical Reports Server (NTRS)

    Bailey, A. J.; Bailey, D. G.; Gaabo, R. J.; Lahn, T. G.; Larson, J. C.; Peterson, E. M.; Schuck, J. W.; Rodgers, D. L.; Wroblewski, K. A.

    1982-01-01

    The Demonstration Advanced Avionics System, DAAS, is an integrated avionics system utilizing microprocessor technologies, data busing, and shared displays for demonstrating the potential of these technologies in improving the safety and utility of general aviation operations in the late 1980's and beyond. Major hardware elements of the DAAS include a functionally distributed microcomputer complex, an integrated data control center, an electronic horizontal situation indicator, and a radio adaptor unit. All processing and display resources are interconnected by an IEEE-488 bus in order to enhance the overall system effectiveness, reliability, modularity and maintainability. A detail description of the DAAS architecture, the DAAS hardware, and the DAAS functions is presented. The system is designed for installation and flight test in a NASA Cessna 402-B aircraft.

  5. NASA's Advanced Space Transportation System launch vehicles

    NASA Technical Reports Server (NTRS)

    Branscome, Darrell R.

    1990-01-01

    An account is given of NASA's Advanced Space Transportation System plans, with a view to the support systems that must be evolved in order to implement such long-term mission requirements; these encompass space-based infrastructure for orbital transfer operations between LEO and GEO, and for operations from LEO to lunar orbit and to Mars. These mission requirements are addressed by the NASA Civil Needs Data Base in order to promote multiple applications. The requisite near-term lift capacity to LEO could be achieved through the development of the Shuttle-derived, unmanned Shuttle-C cargo launch system. Longer-term transportation studies are concerned with the Next Manned Transportation System and Space Transfer Vehicles.

  6. Advanced long term cryogenic storage systems

    NASA Technical Reports Server (NTRS)

    Brown, Norman S.

    1987-01-01

    Long term, cryogenic fluid storage facilities will be required to support future space programs such as the space-based Orbital Transfer Vehicle (OTV), Telescopes, and Laser Systems. An orbital liquid oxygen/liquid hydrogen storage system with an initial capacity of approximately 200,000 lb will be required. The storage facility tank design must have the capability of fluid acquisition in microgravity and limit cryogen boiloff due to environmental heating. Cryogenic boiloff management features, minimizing Earth-to-orbit transportation costs, will include advanced thick multilayer insulation/integrated vapor cooled shield concepts, low conductance support structures, and refrigeration/reliquefaction systems. Contracted study efforts are under way to develop storage system designs, technology plans, test article hardware designs, and develop plans for ground/flight testing.

  7. Advanced extravehicular activity systems requirements definition study

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A study to define the requirements for advanced extravehicular activities (AEVA) was conducted. The purpose of the study was to develop an understanding of the EVA technology requirements and to map a pathway from existing or developing technologies to an AEVA system capable of supporting long-duration missions on the lunar surface. The parameters of an AEVA system which must sustain the crewmembers and permit productive work for long periods in the lunar environment were examined. A design reference mission (DRM) was formulated and used as a tool to develop and analyze the EVA systems technology aspects. Many operational and infrastructure design issues which have a significant influence on the EVA system are identified.

  8. Ferritin nanocontainers that self-direct in synthetic polymer systems

    NASA Astrophysics Data System (ADS)

    Sengonul, Merih C.

    Currently, there are many approaches to introduce functionality into synthetic polymers. Among these, for example, are copolymerization, grafting, and blending methods. However, modifications made by such methods also change the thermodynamics and rheological properties of the polymer system of interest, and each new modification often requires a costly reoptimization of polymer processing. Such a reoptimalization would not be necessary if new functionality could be introduced via a container whose external surface is chemically and physically tuned to interact with the parent polymer. The contents of the container could then be changed without changing other important properties of the parent polymer. In this context this thesis project explores an innovative nanocontainer platform which can be introduced into phase-separating homopolymer blends. Ferritin is a naturally existing nanocontainer that can be used synthetically to package and selectively transport functional moieties to a particular phase that is either in the bulk or on the surface of a homopolymer blend system. The principal focus of this work centers on modifying the surface of wild ferritin to: (1) render modified ferritin soluble in a non-aqueous solvent; and (2) impart it with self-directing properties when exposed to a homopolymer blend surface or incorporated into the bulk of a homopolymer blend. Wild ferritin is water soluble, and this research project successfully modified wild ferritin by grafting either amine-functional poly(ethylene glycol) (PEG) or short-chain alkanes to carbodiimide activated carboxylate groups on ferritin's surface. Such modified ferritin is soluble in dichloromethane (DCM). Modification was confirmed by ion-exchange chromatography, zeta-potential measurements, and electrospray mass spectroscopy. FT-IR was used to quantify the extent of PEGylation of the reaction products through area ratios of the -C-O-C asymmetric stretching vibration of the grafted PEG chains to the

  9. Supramolecular Polymers in Aqueous Media.

    PubMed

    Krieg, Elisha; Bastings, Maartje M C; Besenius, Pol; Rybtchinski, Boris

    2016-02-24

    This review discusses one-dimensional supramolecular polymers that form in aqueous media. First, naturally occurring supramolecular polymers are described, in particular, amyloid fibrils, actin filaments, and microtubules. Their structural, thermodynamic, kinetic, and nanomechanical properties are highlighted, as well as their importance for the advancement of biologically inspired supramolecular polymer materials. Second, five classes of synthetic supramolecular polymers are described: systems based on (1) hydrogen-bond motifs, (2) large π-conjugated surfaces, (3) host-guest interactions, (4) peptides, and (5) DNA. We focus on recent studies that address key challenges in the field, providing mechanistic understanding, rational polymer design, important functionality, robustness, or unusual thermodynamic and kinetic properties. PMID:26727633

  10. Dark matter in the solar system: Hydrogen cyanide polymers

    NASA Astrophysics Data System (ADS)

    Matthews, Clifford N.

    1991-09-01

    In the presence of a base such as ammonia liquid HCN (bp 25 °C) polymerizes readily to a black solid from which a yellow-brown powder can be extracted by water and further hydrolyzed to yieldα-amino acids. These macromolecules could be major components of the dark matter observed on many bodies in the outer solar system. The non-volatile black crust of comet Halley, for example, may consist largely of such polymers, since the original presence on cometary nuclei of frozen volatiles such as methane, ammonia, and water makes them possible sites for the formation and condensed-phase polymerization of hydrogen cyanide. It seems likely, too, that HCN polymers are among the dark —C≡N bearing solids identified spectroscopically by Cruikshanket al. in the dust of some other comets, on the surfaces of several asteroids of spectral class D, within the rings of Uranus, and covering the dark hemisphere of Saturn's satellite Iapetus. HCN polymerization could account also for the yellow-orange-brown coloration of Jupiter and Saturn, as well as for the orange haze high in Titan's atmosphere. Implications for prebiotic chemistry are profound. Primitive Earth may have been covered by HCN polymers through cometary bombardment or terrestrial synthesis, producing a proteinaceous matrix that promoted the molecular interactions leading to the emergence of life.

  11. NASA's advanced space transportation system launch vehicles

    NASA Technical Reports Server (NTRS)

    Branscome, Darrell R.

    1991-01-01

    Some insight is provided into the advanced transportation planning and systems that will evolve to support long term mission requirements. The general requirements include: launch and lift capacity to low earth orbit (LEO); space based transfer systems for orbital operations between LEO and geosynchronous equatorial orbit (GEO), the Moon, and Mars; and Transfer vehicle systems for long duration deep space probes. These mission requirements are incorporated in the NASA Civil Needs Data Base. To accomplish these mission goals, adequate lift capacity to LEO must be available: to support science and application missions; to provide for construction of the Space Station Freedom; and to support resupply of personnel and supplies for its operations. Growth in lift capacity must be time phased to support an expanding mission model that includes Freedom Station, the Mission to Planet Earth, and an expanded robotic planetary program. The near term increase in cargo lift capacity associated with development of the Shuttle-C is addressed. The joint DOD/NASA Advanced Launch System studies are focused on a longer term new cargo capability that will significantly reduce costs of placing payloads in space.

  12. Effects of Molecular Structure in Macroscopic Mechanical Properties of an Advanced Polymer (LARC(sup TM)-SI)

    NASA Technical Reports Server (NTRS)

    Nicholson, Lee M.; Hinkley, Jeffrey A.; Whitley, Karen S.; Gates, Thomas S.

    2004-01-01

    Mechanical testing of an advanced polymer resin with known variations in molecular weight was performed over a range of temperatures below the glass transition temperature. The elastic properties, inelastic elongation behavior, and notched tensile strength all as a function of molecular weight and test temperature were determined. It was shown that notched tensile strength is a strong function of both temperature and molecular weight, whereas stiffness is only a strong function of temperature.

  13. Development and testing of new biologically-based polymers as advanced biocompatible contact lenses

    SciTech Connect

    Bertozzi, Carolyn R.

    2000-06-01

    Nature has evolved complex and elegant materials well suited to fulfill a myriad of functions. Lubricants, structural scaffolds and protective sheaths can all be found in nature, and these provide a rich source of inspiration for the rational design of materials for biomedical applications. Many biological materials are based in some fashion on hydrogels, the crosslinked polymers that absorb and hold water. Biological hydrogels contribute to processes as diverse as mineral nucleation during bone growth and protection and hydration of the cell surface. The carbohydrate layer that coats all living cells, often referred to as the glycocalyx, has hydrogel-like properties that keep cell surfaces well hydrated, segregated from neighboring cells, and resistant to non-specific protein deposition. With the molecular details of cell surface carbohydrates now in hand, adaptation of these structural motifs to synthetic materials is an appealing strategy for improving biocompatibility. The goal of this collaborative project between Prof. Bertozzi's research group, the Center for Advanced Materials at Lawrence Berkeley National Laboratory and Sunsoft Corporation was the design, synthesis and characterization of novel hydrogel polymers for improved soft contact lens materials. Our efforts were motivated by the urgent need for improved materials that allow extended wear, and essential feature for those whose occupation requires the use of contact lenses rather than traditional spectacles. Our strategy was to transplant the chemical features of cell surface molecules into contact lens materials so that they more closely resemble the tissue in which they reside. Specifically, we integrated carbohydrate molecules similar to those found on cell surfaces, and sulfoxide materials inspired by the properties of the carbohydrates, into hydrogels composed of biocompatible and manufacturable substrates. The new materials were characterized with respect to surface and bulk hydrophilicity, and

  14. Advanced Docking System With Magnetic Initial Capture

    NASA Technical Reports Server (NTRS)

    Lewis, James L.; Carroll, Monty B.; Morales, Ray; Le, Thang

    2004-01-01

    An advanced docking system is undergoing development to enable softer, safer docking than was possible when using prior docking systems. This system is intended for original use in docking of visiting spacecraft and berthing the Crew Return Vehicle at the International Space Station (ISS). The system could also be adapted to a variety of other uses in outer space and on Earth, including mating submersible vehicles, assembling structures, and robotic berthing/handling of payloads and cargo. Heretofore, two large spacecraft have been docked by causing the spacecraft to approach each other at a speed sufficient to activate capture latches - a procedure that results in large docking loads and is made more difficult because of the speed. The basic design and mode of operation of the present advanced docking system would eliminate the need to rely on speed of approach to activate capture latches, thereby making it possible to reduce approach speed and thus docking loads substantially. The system would comprise an active subsystem on one spacecraft and a passive subsystem on another spacecraft with which the active subsystem will be docked. The passive subsystem would include an extensible ring containing magnetic striker plates and guide petals. The active subsystem would include mating guide petals and electromagnets containing limit switches and would be arranged to mate with the magnetic striker plates and guide petals of the passive assembly. The electromagnets would be carried on (but not rigidly attached to) a structural ring that would be instrumented with load sensors. The outputs of the sensors would be sent, along with position information, as feedback to an electronic control subsystem. The system would also include electromechanical actuators that would extend or retract the ring upon command by the control subsystem.

  15. Theory of optical transitions in conjugated polymers. II. Real systems

    NASA Astrophysics Data System (ADS)

    Marcus, Max; Tozer, Oliver Robert; Barford, William

    2014-10-01

    The theory of optical transitions developed in Barford and Marcus ["Theory of optical transitions in conjugated polymers. I. Ideal systems," J. Chem. Phys. 141, 164101 (2014)] for linear, ordered polymer chains is extended in this paper to model conformationally disordered systems. Our key result is that in the Born-Oppenheimer regime the emission intensities are proportional to S(1)/⟨IPR⟩, where S(1) is the Huang-Rhys parameter for a monomer. ⟨IPR⟩ is the average inverse participation ratio for the emitting species, i.e., local exciton ground states (LEGSs). Since the spatial coherence of LEGSs determines the spatial extent of chromophores, the significance of this result is that it directly relates experimental observables to chromophore sizes (where ⟨IPR⟩ is half the mean chromophore size in monomer units). This result is independent of the chromophore shape, because of the Born-Oppenheimer factorization of the many body wavefunction. We verify this prediction by density matrix renormalization group (DMRG) calculations of the Frenkel-Holstein model in the adiabatic limit for both linear, disordered chains and for coiled, ordered chains. We also model optical spectra for poly(p-phenylene) and poly(p-phenylene-vinylene) oligomers and polymers. For oligomers, we solve the fully quantized Frenkel-Holstein model via the DMRG method. For polymers, we use the much simpler method of solving the one-particle Frenkel model and employ the Born-Oppenheimer expressions relating the effective Franck-Condon factor of a chromophore to its inverse participation ratio. We show that increased disorder decreases chromophore sizes and increases the inhomogeneous broadening, but has a non-monotonic effect on transition energies. We also show that as planarizing the polymer chain increases the exciton band width, it causes the chromophore sizes to increase, the transition energies to decrease, and the broadening to decrease. Finally, we show that the absorption spectra are

  16. A European advanced data relay system

    NASA Astrophysics Data System (ADS)

    de Agostini, Agostino; Puccio, Antonio; Zanotti, Glullo

    1990-10-01

    The purpose of the study is to select the most attractive configuration(s) for an advanced data relay system to be employed at the beginning of the next century. A users scenario with such user classes as a manned in-orbit infrastructure and related support, launchers/transit vehicles, earth observation spacecraft, automatic microgravity free flyers, and scientific spacecraft is considered. System architecture is discussed in terms of configuration analysis and resources definition. The analysis of the space segment contains the definition of link requirements and payloads, as well as mass/power budget and accommodations on space platforms, and the ground segment is assessed from the system-facility and user earth-terminal points of view. Cost analysis and trade-offs are presented, and the key parameters such as the zone of exclusion, service availability, service continuity, intersatellite link implementation, feeder link, platform configuration, ground infrastructure, and economic viability are considered.

  17. An advanced domestic satellite communications system

    NASA Technical Reports Server (NTRS)

    1980-01-01

    An updated traffic projection for U.S. domestic satellite communications service covering a period of 15 years; mid-1980 to mid-1995 was prepared. This model takes into account expected technology advances and reductions in transmission costs, legislative and regulatory changes permitting increased competition, and rising energy costs which will encourage more extensive substitution of telecommunications for travel. The historical development and current status of satellite systems are discussed as well as the characteristics of follow-on systems. Orbital arc utilization, spacecraft configuration for single shuttle launch, Earth station configuration, and system costs are examined. Areas which require technology development include multiple beam frequency reuse antennas, on-board switching, intersatellite links, and ka-band operation. Packing and deployment schemes for enclosing the satellite within the shuttle orbiter bay must also be devised.

  18. Industrial Advanced Turbine Systems Program overview

    SciTech Connect

    Esbeck, D.W.

    1995-10-01

    The U.S. Department of Energy (DOE), in partnership with industry, has set new performance standards for industrial gas turbines through the creation of the Industrial Advanced Turbine System Program. Their leadership will lead to the development of an optimized, energy efficient, and environmentally friendly gas turbine power systems in this size class (3-to-20 MW). The DOE has already created a positive effect by encouraging gas turbine system manufacturers to reassess their product and technology plans using the new higher standards as the benchmark. Solar Turbines has been a leader in the industrial gas turbine business, and is delighted to have joined with the DOE in developing the goals and vision for this program. We welcome the opportunity to help the national goals of energy conservation and environmental enhancement. The results of this program should lead to the U.S. based gas turbine industry maintaining its international leadership and the creation of highly paid domestic jobs.

  19. Advanced systems engineering and network planning support

    NASA Technical Reports Server (NTRS)

    Walters, David H.; Barrett, Larry K.; Boyd, Ronald; Bazaj, Suresh; Mitchell, Lionel; Brosi, Fred

    1990-01-01

    The objective of this task was to take a fresh look at the NASA Space Network Control (SNC) element for the Advanced Tracking and Data Relay Satellite System (ATDRSS) such that it can be made more efficient and responsive to the user by introducing new concepts and technologies appropriate for the 1997 timeframe. In particular, it was desired to investigate the technologies and concepts employed in similar systems that may be applicable to the SNC. The recommendations resulting from this study include resource partitioning, on-line access to subsets of the SN schedule, fluid scheduling, increased use of demand access on the MA service, automating Inter-System Control functions using monitor by exception, increase automation for distributed data management and distributed work management, viewing SN operational control in terms of the OSI Management framework, and the introduction of automated interface management.

  20. Advanced extravehicular protective systems study, volume 1

    NASA Technical Reports Server (NTRS)

    Sutton, J. G.; Heimlich, P. F.; Tepper, E. H.

    1972-01-01

    An appraisal was made of advanced portable and emergency life support systems concepts for space station, space shuttle, lunar base, and Mars EVA missions. Specifications are given, and the methodology is described. Subsystem studies and systems integration efforts are summarized. Among the conclusions are the following: (1) For long duration missions, a configuration incorporating a regenerable CO2 control subsystem and a thermal control subsystem utilizing a minimum of expendables decreases the vehicle penalty of present configurations. (2) For shorter duration missions, a configuration incorporating an expendable water thermal control subsystem is the most competitive subsystem; regenerable CO2 control subsystems if properly developed are competitive with nonregenerable counterparts. (3) The CO2 reduction and oxygen reclamation withing the parent vehicle is only competitive when there are three or more parent vehicle resupply periods. (4) For long duration emergency systems of one hour or more, inherent redundancy within the primary configuration to provide emergency thermal control is the most competitive approach.

  1. Industrial Advanced Turbine Systems Program overview

    SciTech Connect

    Esbeck, D.W.

    1995-12-31

    DOE`s ATS Program will lead to the development of an optimized, energy efficient, and environmentally friendly gas turbine power systems in the 3 to 20 MW class. Market studies were conducted for application of ATS to the dispersed/distributed electric power generation market. The technology studies have led to the design of a gas-fired, recuperated, industrial size gas turbine. The Ceramic Stationary Gas Turbine program continues. In the High Performance Steam Systems program, a 100 hour development test to prove the advanced 1500 F, 1500 psig system has been successfully completed. A market transformation will take place: the customer will be offered a choice of energy conversion technologies to meet heat and power generation needs into the next century.

  2. Advanced Querying Features for Disease Surveillance Systems

    PubMed Central

    Hashemian, Mohammad R.

    2010-01-01

    Most automated disease surveillance systems notify users of increases in the prevalence of reports in syndrome categories and allow users to view patient level data related to those increases. Occasionally, a more dynamic level of control is required to properly detect an emerging disease in a community. Dynamic querying features are invaluable when using existing surveillance systems to investigate outbreaks of newly emergent diseases or to identify cases of reportable diseases within data being captured for surveillance. The objective of the Advance Querying Tool (AQT) is to build a more flexible query interface for most web-based disease surveillance systems. This interface allows users to define and build their query as if they were writing a logical expression for a mathematical computation. The AQT allows users to develop, investigate, save, and share complex case definitions. It provides a flexible interface that accommodates both advanced and novice users, checks the validity of the expression as it is built, and marks errors for users. PMID:23569575

  3. Advanced electronics for the CTF MEG system.

    PubMed

    McCubbin, J; Vrba, J; Spear, P; McKenzie, D; Willis, R; Loewen, R; Robinson, S E; Fife, A A

    2004-01-01

    Development of the CTF MEG system has been advanced with the introduction of a computer processing cluster between the data acquisition electronics and the host computer. The advent of fast processors, memory, and network interfaces has made this innovation feasible for large data streams at high sampling rates. We have implemented tasks including anti-alias filter, sample rate decimation, higher gradient balancing, crosstalk correction, and optional filters with a cluster consisting of 4 dual Intel Xeon processors operating on up to 275 channel MEG systems at 12 kHz sample rate. The architecture is expandable with additional processors to implement advanced processing tasks which may include e.g., continuous head localization/motion correction, optional display filters, coherence calculations, or real time synthetic channels (via beamformer). We also describe an electronics configuration upgrade to provide operator console access to the peripheral interface features such as analog signal and trigger I/O. This allows remote location of the acoustically noisy electronics cabinet and fitting of the cabinet with doors for improved EMI shielding. Finally, we present the latest performance results available for the CTF 275 channel MEG system including an unshielded SEF (median nerve electrical stimulation) measurement enhanced by application of an adaptive beamformer technique (SAM) which allows recognition of the nominal 20-ms response in the unaveraged signal. PMID:16012695

  4. Advanced integrated life support system update

    NASA Technical Reports Server (NTRS)

    Whitley, Phillip E.

    1994-01-01

    The Advanced Integrated Life Support System Program (AILSS) is an advanced development effort to integrate the life support and protection requirements using the U.S. Navy's fighter/attack mission as a starting point. The goal of AILSS is to optimally mate protection from altitude, acceleration, chemical/biological agent, thermal environment (hot, cold, and cold water immersion) stress as well as mission enhancement through improved restraint, night vision, and head-mounted reticules and displays to ensure mission capability. The primary emphasis to date has been to establish garment design requirements and tradeoffs for protection. Here the garment and the human interface are treated as a system. Twelve state-off-the-art concepts from government and industry were evaluated for design versus performance. On the basis of a combination of centrifuge, thermal manikin data, thermal modeling, and mobility studies, some key design parameters have been determined. Future efforts will concentrate on the integration of protection through garment design and the use of a single layer, multiple function concept to streamline the garment system.

  5. Systems Analyses of Advanced Brayton Cycles

    SciTech Connect

    A.D. Rao; D.J. Francuz; J.D. Maclay; J. Brouwer; A. Verma; M. Li; G.S. Samuelsen

    2008-09-30

    The main objective is to identify and assess advanced improvements to the Brayton Cycle (such as but not limited to firing temperature, pressure ratio, combustion techniques, intercooling, fuel or combustion air augmentation, enhanced blade cooling schemes) that will lead to significant performance improvements in coal based power systems. This assessment is conducted in the context of conceptual design studies (systems studies) that advance state-of-art Brayton cycles and result in coal based efficiencies equivalent to 65% + on natural gas basis (LHV), or approximately an 8% reduction in heat rate of an IGCC plant utilizing the H class steam cooled gas turbine. H class gas turbines are commercially offered by General Electric and Mitsubishi for natural gas based combined cycle applications with 60% efficiency (LHV) and it is expected that such machine will be offered for syngas applications within the next 10 years. The studies are being sufficiently detailed so that third parties will be able to validate portions or all of the studies. The designs and system studies are based on plants for near zero emissions (including CO{sub 2}). Also included in this program is the performance evaluation of other advanced technologies such as advanced compression concepts and the fuel cell based combined cycle. The objective of the fuel cell based combined cycle task is to identify the desired performance characteristics and design basis for a gas turbine that will be integrated with an SOFC in Integrated Gasification Fuel Cell (IGFC) applications. The goal is the conceptualization of near zero emission (including CO{sub 2} capture) integrated gasification power plants producing electricity as the principle product. The capability of such plants to coproduce H{sub 2} is qualitatively addressed. Since a total systems solution is critical to establishing a plant configuration worthy of a comprehensive market interest, a baseline IGCC plant scheme is developed and used to study

  6. End-evaporation kinetics in living-polymer systems

    NASA Astrophysics Data System (ADS)

    Marques, C. M.; Turner, M. S.; Cates, M. E.

    1993-11-01

    We study theoretically the process of ``end-evaporation'' in living polymer systems, such as wormlike surfactant micelles. End-evaporation occurs when single monomers either break away from, or join onto, a chain end, the rates being described by the (mean-field) rate constants k and k', respectively. Thus the chains can exchange material with one-another via a bath of free monomers. The relaxation of a system of living polymers after a small temperature jump (T-jump) is studied theoretically. The effect of a T-jump is to prepare the system with the wrong mean chain length, which relaxes to its equilibrium value L¯ by end-evaporation. It is found that the number of free monomers in the system relaxes almost completely in a time of order 1/kL¯, while the weight-average chain length, which is the quantity measured in light scattering experiments, relaxes on a time scale τD=4L¯2/k, which is three powers of L¯ longer. We also predict that the stress relaxation after a step strain is dominated by end-evaporation whenever τD≲τrep, where τrep is the reptation (disengagement) time for a chain of length L¯. In this case the stress relaxation is found to be ``stretched exponential'' for times smaller than τD and single exponential for longer times.

  7. Advanced high frequency partial discharge measuring system

    NASA Technical Reports Server (NTRS)

    Karady, George G.

    1994-01-01

    This report explains the Advanced Partial Discharge Measuring System in ASU's High Voltage Laboratory and presents some of the results obtained using the setup. While in operation an insulation is subjected to wide ranging temperature and voltage stresses. Hence, it is necessary to study the effect of temperature on the behavior of partial discharges in an insulation. The setup described in this report can be used to test samples at temperatures ranging from -50 C to 200 C. The aim of conducting the tests described herein is to be able to predict the behavior of an insulation under different operating conditions in addition to being able to predict the possibility of failure.

  8. ADVANCED GAS TURBINE SYSTEMS RESEARCH PROGRAM

    SciTech Connect

    Lawrence P. Golan

    2003-05-01

    The activities of the Advanced Gas Turbine Systems Research (AGTSR) program for the reporting period October 1, 2002 to December 31, 2002 are described in this quarterly report. No new membership, workshops, research projects, internships, faculty fellowships or special studies were initiated during this reporting period. Contract completion is set for June 30, 2003. During the report period, six research progress reports were received (3 final reports and 3 semi-annual reports). The University of Central Florida contract SR080 was terminated during this period, as UCF was unable to secure research facilities. AGTSR now projects that it will under spend DOE obligated funds by approximately 340-350K$.

  9. Advanced vehicle systems assessment. Volume 3: Systems assessment

    NASA Technical Reports Server (NTRS)

    Hardy, K.

    1985-01-01

    The systems analyses integrate the advanced component and vehicle characteristics into conceptual vehicles with identical performance (for a given application) and evaluates the vehicles in typical use patterns. Initial and life-cycle costs are estimated and compared to conventional reference vehicles with comparable technological advances, assuming the vehicles will be in competition in the early 1990s. Electric vans, commuter vehicles, and full-size vehicles, in addition to electric/heat-engine hybrid and fuel-cell powered vehicles, are addressed in terms of performance and economics. System and subsystem recommendations for vans and two-passenger commuter vehicles are based on the economic analyses in this volume.

  10. Automated Operations Development for Advanced Exploration Systems

    NASA Technical Reports Server (NTRS)

    Haddock, Angie; Stetson, Howard K.

    2012-01-01

    Automated space operations command and control software development and its implementation must be an integral part of the vehicle design effort. The software design must encompass autonomous fault detection, isolation, recovery capabilities and also provide single button intelligent functions for the crew. Development, operations and safety approval experience with the Timeliner system on-board the International Space Station (ISS), which provided autonomous monitoring with response and single command functionality of payload systems, can be built upon for future automated operations as the ISS Payload effort was the first and only autonomous command and control system to be in continuous execution (6 years), 24 hours a day, 7 days a week within a crewed spacecraft environment. Utilizing proven capabilities from the ISS Higher Active Logic (HAL) System [1] , along with the execution component design from within the HAL 9000 Space Operating System [2] , this design paper will detail the initial HAL System software architecture and interfaces as applied to NASA s Habitat Demonstration Unit (HDU) in support of the Advanced Exploration Systems, Autonomous Mission Operations project. The development and implementation of integrated simulators within this development effort will also be detailed and is the first step in verifying the HAL 9000 Integrated Test-Bed Component [2] designs effectiveness. This design paper will conclude with a summary of the current development status and future development goals as it pertains to automated command and control for the HDU.

  11. Automated Operations Development for Advanced Exploration Systems

    NASA Technical Reports Server (NTRS)

    Haddock, Angie T.; Stetson, Howard

    2012-01-01

    Automated space operations command and control software development and its implementation must be an integral part of the vehicle design effort. The software design must encompass autonomous fault detection, isolation, recovery capabilities and also provide "single button" intelligent functions for the crew. Development, operations and safety approval experience with the Timeliner system onboard the International Space Station (ISS), which provided autonomous monitoring with response and single command functionality of payload systems, can be built upon for future automated operations as the ISS Payload effort was the first and only autonomous command and control system to be in continuous execution (6 years), 24 hours a day, 7 days a week within a crewed spacecraft environment. Utilizing proven capabilities from the ISS Higher Active Logic (HAL) System, along with the execution component design from within the HAL 9000 Space Operating System, this design paper will detail the initial HAL System software architecture and interfaces as applied to NASA's Habitat Demonstration Unit (HDU) in support of the Advanced Exploration Systems, Autonomous Mission Operations project. The development and implementation of integrated simulators within this development effort will also be detailed and is the first step in verifying the HAL 9000 Integrated Test-Bed Component [2] designs effectiveness. This design paper will conclude with a summary of the current development status and future development goals as it pertains to automated command and control for the HDU.

  12. Advanced coal-fueled gas turbine systems

    SciTech Connect

    Wenglarz, R.A.

    1994-08-01

    Several technology advances since the early coal-fueled turbine programs that address technical issues of coal as a turbine fuel have been developed in the early 1980s: Coal-water suspensions as fuel form, improved methods for removing ash and contaminants from coal, staged combustion for reducing NO{sub x} emissions from fuel-bound nitrogen, and greater understanding of deposition/erosion/corrosion and their control. Several Advanced Coal-Fueled Gas Turbine Systems programs were awarded to gas turbine manufacturers for for components development and proof of concept tests; one of these was Allison. Tests were conducted in a subscale coal combustion facility and a full-scale facility operating a coal combustor sized to the Allison Model 501-K industrial turbine. A rich-quench-lean (RQL), low nitrogen oxide combustor design incorporating hot gas cleanup was developed for coal fuels; this should also be applicable to biomass, etc. The combustor tests showed NO{sub x} and CO emissions {le} levels for turbines operating with natural gas. Water washing of vanes from the turbine removed the deposits. Systems and economic evaluations identified two possible applications for RQL turbines: Cogeneration plants based on Allison 501-K turbine (output 3.7 MW(e), 23,000 lbs/hr steam) and combined cycle power plants based on 50 MW or larger gas turbines. Coal-fueled cogeneration plant configurations were defined and evaluated for site specific factors. A coal-fueled turbine combined cycle plant design was identified which is simple, compact, and results in lower capital cost, with comparable efficiency and low emissions relative to other coal technologies (gasification, advanced PFBC).

  13. Distributed Sensor Coordination for Advanced Energy Systems

    SciTech Connect

    Tumer, Kagan

    2013-07-31

    The ability to collect key system level information is critical to the safe, efficient and reli- able operation of advanced energy systems. With recent advances in sensor development, it is now possible to push some level of decision making directly to computationally sophisticated sensors, rather than wait for data to arrive to a massive centralized location before a decision is made. This type of approach relies on networked sensors (called “agents” from here on) to actively collect and process data, and provide key control deci- sions to significantly improve both the quality/relevance of the collected data and the as- sociating decision making. The technological bottlenecks for such sensor networks stem from a lack of mathematics and algorithms to manage the systems, rather than difficulties associated with building and deploying them. Indeed, traditional sensor coordination strategies do not provide adequate solutions for this problem. Passive data collection methods (e.g., large sensor webs) can scale to large systems, but are generally not suited to highly dynamic environments, such as ad- vanced energy systems, where crucial decisions may need to be reached quickly and lo- cally. Approaches based on local decisions on the other hand cannot guarantee that each agent performing its task (maximize an agent objective) will lead to good network wide solution (maximize a network objective) without invoking cumbersome coordination rou- tines. There is currently a lack of algorithms that will enable self-organization and blend the efficiency of local decision making with the system level guarantees of global decision making, particularly when the systems operate in dynamic and stochastic environments. In this work we addressed this critical gap and provided a comprehensive solution to the problem of sensor coordination to ensure the safe, reliable, and robust operation of advanced energy systems. The differentiating aspect of the proposed work is in shift- ing

  14. Sitosterol bioconversion with resting cells in liquid polymer based systems.

    PubMed

    Carvalho, Filipe; Marques, Marco P C; de Carvalho, Carla C C R; Cabral, Joaquim M S; Fernandes, Pedro

    2009-09-01

    The use of a biocompatible water-immiscible organic phase as a substrate and product pool has been acknowledged as an effective tool to overcome the low volumetric productivity of aqueous bioconversion systems involving hydrophobic compounds. The growing environmental and public health awareness is nevertheless leading to restrictions in the use of organic solvents in industrial processes, in order to render these more environmentally friendly. Different approaches are hence being assessed for the design of alternative bioconversion media, involving the use of supercritical fluids, ionic liquids and natural oils and liquid polymers, among others. In this work, the use of liquid polymers as key components in the bioconversion media for a multi-step microbial bioconversion was assessed. The model system used was the selective cleavage of the side-chain of beta-sitosterol by free resting cells of Mycobacterium sp. NRRL B-3805, a well established industrial multi-enzymatic process involving the use of nine catabolic enzymes in a fourteen-step metabolic pathway. High product yields were obtained when silicone B oil was used as substrate carrier/product pool, both in single oil and in oil:buffer two liquid phase system. PMID:19362822

  15. Advances in Systemic siRNA Delivery

    PubMed Central

    Leng, Qixin; Woodle, Martin C; Lu, Patrick Y; Mixson, A James

    2009-01-01

    Sequence-specific gene silencing with small interfering RNA (siRNA) has transformed basic science research, and the efficacy of siRNA therapeutics toward a variety of diseases is now being evaluated in pre-clinical and clinical trials. Despite its potential value, the highly negatively charged siRNA has the classic delivery problem of requiring transport across cell membranes to the cytosol. Consequently, carrier development for siRNA delivery is one of the most important problems to solve before siRNA can achieve widespread clinical use. An assortment of non-viral carriers including liposomes, peptides, polymers, and aptamers are being evaluated for their ability to shepherd siRNA to the target tissue and cross the plasma membrane barrier into the cell. Several promising carriers with low toxicity and increased specificity for disease targets have emerged for siRNA-based therapeutics. This review will discuss non-viral approaches for siRNA therapeutics, with particular focus on synthetic carriers for in vivo systemic delivery of siRNA. PMID:20161621

  16. NASA's Space Launch System Advanced Booster Development

    NASA Technical Reports Server (NTRS)

    Robinson, Kimberly F.; Crumbly, Christopher M.; May, Todd A.

    2014-01-01

    The National Aeronautics and Space Administration's (NASA's) Space Launch System (SLS) Program, managed at the Marshall Space Flight Center, is making progress toward delivering a new capability for human space flight and scientific missions beyond Earth orbit. NASA is executing this development within flat budgetary guidelines by using existing engines assets and heritage technology to ready an initial 70 metric ton (t) lift capability for launch in 2017, and then employing a block upgrade approach to evolve a 130-t capability after 2021. A key component of the SLS acquisition plan is a three-phased approach for the first-stage boosters. The first phase is to expedite the 70-t configuration by completing development of the Space Shuttle heritage 5-segment solid rocket boosters (SRBs) for the initial flights of SLS. Since no existing boosters can meet the performance requirements for the 130-t class SLS, the next phases of the strategy focus on the eventual development of advanced boosters with an expected thrust class potentially double the current 5-segment solid rocket booster capability of 3.88 million pounds of thrust each. The second phase in the booster acquisition plan is the Advanced Booster Engineering Demonstration and/or Risk Reduction (ABEDRR) effort, for which contracts were awarded beginning in 2012 after a full and open competition, with a stated intent to reduce risks leading to an affordable advanced booster. NASA has awarded ABEDRR contracts to four industry teams, which are looking into new options for liquid-fuel booster engines, solid-fuel-motor propellants, and composite booster structures. Demonstrations and/or risk reduction efforts were required to be related to a proposed booster concept directly applicable to fielding an advanced booster. This paper will discuss the status of this acquisition strategy and its results toward readying both the 70 t and 130 t configurations of SLS. The third and final phase will be a full and open

  17. Materials Requirements for Advanced Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Whitaker, Ann F.; Cook, Mary Beth; Clinton, R. G., Jr.

    2005-01-01

    NASA's mission to "reach the Moon and Mars" will be obtained only if research begins now to develop materials with expanded capabilities to reduce mass, cost and risk to the program. Current materials cannot function satisfactorily in the deep space environments and do not meet the requirements of long term space propulsion concepts for manned missions. Directed research is needed to better understand materials behavior for optimizing their processing. This research, generating a deeper understanding of material behavior, can lead to enhanced implementation of materials for future exploration vehicles. materials providing new approaches for manufacture and new options for In response to this need for more robust materials, NASA's Exploration Systems Mission Directorate (ESMD) has established a strategic research initiative dedicated to materials development supporting NASA's space propulsion needs. The Advanced Materials for Exploration (AME) element directs basic and applied research to understand material behavior and develop improved materials allowing propulsion systems to operate beyond their current limitations. This paper will discuss the approach used to direct the path of strategic research for advanced materials to ensure that the research is indeed supportive of NASA's future missions to the moon, Mars, and beyond.

  18. Advanced turbine systems: Studies and conceptual design

    SciTech Connect

    van der Linden, S.; Gnaedig, G.; Kreitmeier, F.

    1993-11-01

    The ABB selection for the Advanced Turbine System (ATS) includes advanced developments especially in the hot gas path of the combustion turbine and new state-of-the-art units such as the steam turbine and the HRSG. The increase in efficiency by more than 10% multiplicative compared to current designs will be based on: (1) Turbine Inlet Temperature Increase; (2) New Cooling Techniques for Stationary and Rotating Parts; and New Materials. Present, projected component improvements that will be introduced with the above mentioned issues will yield improved CCSC turbine performance, which will drive the ATS selected gas-fired reference CC power plant to 6 % LHV or better. The decrease in emission levels requires a careful optimization of the cycle design, where cooling air consumption has to be minimized. All interfaces of the individual systems in the complete CC Plant need careful checks, especially to avoid unnecessary margins in the individual designs. This study is an important step pointing out the feasibility of the ATS program with realistic goals set by DOE, which, however, will present challenges for Phase II time schedule of 18 months. With the approach outlined in this study and close cooperation with DOE, ATS program success can be achieved to deliver low emissions and low cost of electricity by the year 2002. The ABB conceptual design and step approach will lead to early component demonstration which will help accelerate the overall program objectives.

  19. Advanced Process Model for Polymer Pyrolysis and Uranium Ceramic Material Processing

    SciTech Connect

    Wang, Xiaolin; Zunjarrao, Suraj C.; Zhang, Hui; Singh, Raman P.

    2006-07-01

    Silicon carbide (SiC) based uranium ceramic material can be fabricated as hosts for ultra high temperature applications, such as gas-cooled fast reactor fuels and in-core materials. A pyrolysis-based material processing technique allows for the fabrication of SiC based uranium ceramic materials at a lower temperature compared to sintering route. Modeling of the process is considered important for optimizing the fabrication and producing material with high uniformity. This study presents a process model describing polymer pyrolysis and uranium ceramic material processing, including heat transfer, polymer pyrolysis, SiC crystallization, chemical reactions, and species transport of a porous uranium oxide mixed polymer. Three key reactions for polymer pyrolysis and one key reaction for uranium oxide polymer interaction are established for the processing. Included in the model formulation are the effects of transport processes such as heat-up, polymer decomposition, and volatiles escape. The model is capable of accurately predicting the polymer pyrolysis and chemical reactions of the source material. Processing of a sample with certain geometry is simulated. The effects of heating rate, particle size and volume ratio of uranium oxide and polymer on porosity evolution, species uniformity, reaction rate are investigated. (authors)

  20. Basics and advances in battery systems

    SciTech Connect

    Nelson, J.P.; Bolin, W.D.

    1995-03-01

    One of the most common components in both the utility and industrial/commercial power system is the station battery. In many cases, the original design is marginal or inadequate; the maintenance and testing is practically nonexistent; but the system is called upon during emergency conditions and is expected to perform flawlessly. This paper will begin with the basic battery theory starting with the electrochemical cell. A working knowledge of the battery cell is important to understand typical problems such as hydrogen production, sulfating, and battery charging. The paper will then lead into a discussion of some of the common batteries and battery chargers. While this paper will concentrate primarily on the lead acid type of battery, the theory can be utilized on other types such as the Nickel-Cadmium. A reference will be made to industry standards and codes which are used for the design, installation, and maintenance of battery systems. Along with these standards will be a discussion of the design considerations, maintenance and testing, and, finally, some advanced battery system topics such as individual battery cell voltage equalizers and battery pulsing units. The goal of this paper is to provide the reader with a basic working understanding of a battery system. Only with that knowledge can a person be expected to design and/or properly maintain a battery system which may be called upon during an emergency to minimize the effects of a normal power outage, to minimize personnel hazards and to reduce property damage.

  1. Advanced hybrid vehicle propulsion system study

    NASA Technical Reports Server (NTRS)

    Schwarz, R.

    1982-01-01

    Results are presented of a study of an advanced heat engine/electric automotive hybrid propulsion system. The system uses a rotary stratified charge engine and ac motor/controller in a parallel hybrid configuration. The three tasks of the study were (1) parametric studies involving five different vehicle types, (2) design trade-off studies to determine the influence of various vehicle and propulsion system paramaters on system performance fuel economy and cost, and (3) a conceptual design establishing feasibility at the selected approach. Energy consumption for the selected system was .034 1/km (61.3 mpg) for the heat engine and .221 kWh/km (.356 kWh/mi) for the electric power system over a modified J227 a schedule D driving cycle. Life cycle costs were 7.13 cents/km (11.5 cents/mi) at $2/gal gasoline and 7 cents/kWh electricity for 160,000 km (100,000 mi) life.

  2. Advancements in low NOx tangential firing systems

    SciTech Connect

    Hein, R. von; Maney, C.; Borio, R.

    1996-12-31

    The most cost effective method of reducing nitrogen oxide emissions when burning fossil fuels, such as coal, is through in-furnace NOx reduction processes. ABB Combustion Engineering, Inc. (ABB CE), through its ABB Power Plant Laboratories has been involved in the development of such low NOx pulverized coal firing systems for many years. This development effort is most recently demonstrated through ABB CE`s involvement with the U.S. Department of Energy`s (DOE) {open_quotes}Engineering Development of Advanced Coal Fired Low-Emission Boiler Systems{close_quotes} (LEBS) project. The goal of the DOE LEBS project is to use {open_quotes}near term{close_quotes} technologies to produce a commercially viable, low emissions boiler. This paper addresses one of the key technologies within this project, the NOx control subsystem. The foundation for the work undertaken at ABB CE is the TFS 2000{trademark} firing system, which is currently offered on a commercial basis. This system encompasses sub-stoichiometric combustion in the main firing zone for reduced NOx formation. Potential enhancements to this firing system focus on optimizing the introduction of the air and fuel within the primary windbox to provide additional horizontal and vertical staging. As is the case with all in-furnace NOx control processes, it is necessary to operate the system in a manner which does not decrease NOx at the expense of reduced combustion efficiency.

  3. ACTS advanced system concepts and experimentation

    NASA Technical Reports Server (NTRS)

    Abbe, Brian S.; Theofylaktos, Noulie

    1993-01-01

    Over the course of the first two years of experimentation with the Advanced Communications Technology Satellite (ACTS), many different K/Ka-band applications-oriented experiments will be conducted and evaluated for their commercial viability. In addition, the technological developments and advanced systems concepts associated with the various terminals and the satellite itself will also be examined. Beyond these existing experiments and the current terminal developments, many other new and exciting experiment ideas and advanced system concepts exist. With the additional use of ACTS for the last two years of its lifetime, many of these ideas could be explored. In the mobile satellite communications arena, a particular applications-oriented concept that has yet to be developed is a maritime-mobile experiment. Applications of K/Ka-band mobile satcom technologies to the pleasure cruise industry could provide similar communications services as those that are being developed for the broadband aeronautical experiments. A second applications-oriented experiment that could be of interest is the development of a hybrid satellite-cellular system experiment. In such an experimental system, a mobile K/Ka-band satellite service would extend the coverage of the already existing cellular network. Many new system concepts and terminal developments could also be accomplished. The initial characterization of the K/Ka-band mobile satellite communications propagation channel and evaluation of the currently existing rain compensation algorithms (RCA's) could lead to a second generation RCA development that would improve the overall ACTS Mobile Terminal (AMT) performance. In addition, the development of an enhanced modem to be used with the AMT that utilizes CDMA spread spectrum would also improve the overall terminal efficiency and provide a greater commercial potential for K/Ka-band applications. Other techniques worthy of further exploration and evaluation include the development of

  4. Raman and FTIR imaging of dynamic polymer systems

    NASA Astrophysics Data System (ADS)

    Bobiak, John Peter

    This work aims to expand the applications of Raman and infrared imaging in materials science and engineering. Recent developments in spectroscopic imaging technology have led to relatively fast image acquisition rates, enabling the in situ analysis of various engineering processes. A brief review of spectroscopic imaging principles and existing applications is provided as background before three novel applications are set forth. First, the effectiveness of FTIR imaging for modeling polymer dissolution behavior was examined in a series of binary poly (methyl methacrylate) (PMMA) systems. The dissolution behavior was influenced by polymer conformation as well as the solvent characteristics. The results indicate that chemistry alone is a poor predictor of dissolution rate. Rather, the diffusion coefficients of both the polymer and solvent have a foremost impact on the dissolution process. One major complication in modeling diffusion-related process by FTIR imaging is the precise determination of component locations in a series of images. This issue is addressed through the introduction of a new position-reporting technique based on hypothesis testing. A rudimentary drug release system, consisting of a poly (ethylene-co-vinyl acetate) film and a nicotine solution, was used to illustrate the importance of precisely reporting the nicotine diffusion front position. The new reporting method provided an inherent level of certainty to the position report. This method was applied to qualitatively assess the uptake of nicotine from solutions containing different solubilizing agents, which were capable of either promoting or inhibiting nicotine uptake. Finally, Raman mapping and Raman line imaging were used to classify individual carbon nanotubes that were dispersed on a substrate. Individual nanotubes displayed a range of spectral characteristics, indicating that the bulk sample was a mixture of materials with different graphitic domain sizes. The results from images acquired

  5. Polymer biomaterial constructs for regenerative medicine and functional biological systems

    NASA Astrophysics Data System (ADS)

    Meng, Linghui

    The use of collagen as a biomaterial is currently undergoing a renaissance in the tissue engineering field. The excellent biocompatibility and safety due to its biological characteristics, such as biodegradability and weak antigenicity, make collagen a primary material resource in medical applications. Described herein is work towards the development of novel collagen-based matrices, with additional multi-functionality imparted through a novel in-situ crosslinking approach. The process of electrospinning has become a widely used technique for the creation of fibrous scaffolds for tissue engineering applications due to its ability to rapidly create structures composed of nano-scale polymer fibers closely resembling the architecture of the extracellular matrix (ECM). Collagen-PCL sheath-core bicomponent fibrous scaffolds were fabricated using a novel variation on traditional electrospinning, known as co-axial electrospinning. The results showed that the addition of a synthetic polymer core into collagen nanofibers remarkably increased the mechanical strength of collagen matrices spun from the benign solvent system. A novel single-step, in-situ collagen crosslink approach was developed in order to solve the problems dominating traditional collagen crosslinking methods, such as dimensional shrinking and loss of porous morphology, and to simplify the crosslinking procedure for electrospun collagen scaffolds. The excess amount of NHS present in the crosslinking mixture was found to delay the EDC/collagen coupling reaction in a controlled fashion. Fundamental investigations into the development and characterization of in-situ crosslinked collagen matrices such as fibrous scaffolds, gels and sponges, as well as their biomedical applications including cell culture substrates, wound dressings, drug delivery matrices and bone regeneration substitutes, were performed. The preliminary mice studies indicated that the in-situ crosslinked collagen matrices could be good candidates

  6. Advanced materials for space nuclear power systems

    SciTech Connect

    Titran, R.H.; Grobstein, T.L. . Lewis Research Center); Ellis, D.L. )

    1991-01-01

    Research on monolithic refractory metal alloys and on metal matrix composites is being conducted at the NASA Lewis Research Center, Cleveland, Ohio, in support of advanced space power systems. The overall philosophy of the research is to develop and characterize new high-temperature power conversion and radiator materials and to provide spacecraft designers with material selection options and design information. Research on three candidate materials (carbide strengthened niobium alloy PWC-11 for fuel cladding, graphite fiber reinforced copper matrix composites (Gr/Cu) for heat rejection fins, and tungsten fiber reinforced niobium matrix composites (W/NB) for fuel containment and structural supports) considered for space power system applications is discussed. Each of these types of materials offers unique advantages for space power applications.

  7. 21st century advanced hydropower turbine system

    SciTech Connect

    Brookshier, P.A.; Flynn, J.V.; Loose, R.R.

    1995-11-01

    While hydropower turbine manufacturers have incrementally improved turbine technology to increase efficiency, the basic design concepts haven`t changed for decades. These late 19th and early 20th century designs did not consider environmental effects, since little was known about environmental effects of hydropower at the time. The U.S. Department of Energy (DOE) and the hydropower industry recognize that hydropower plants have an effect on the environment and there is a great need to bring turbine designs into the 21st century. DOE has issued a request for proposals (RFP) that requested proposers to discard conventional thinking, search out innovative solutions, and to visualize innovative turbines designed from a new perspective. This perspective would look at the {open_quotes}turbine system{close_quotes} (intake to tailrace) which will balance environmental, technical, and economic considerations. This paper describes the DOE Advanced Hydropower Turbine System Program.

  8. Advanced recovery systems wind tunnel test report

    NASA Technical Reports Server (NTRS)

    Geiger, R. H.; Wailes, W. K.

    1990-01-01

    Pioneer Aerospace Corporation (PAC) conducted parafoil wind tunnel testing in the NASA-Ames 80 by 120 test sections of the National Full-Scale Aerodynamic Complex, Moffett Field, CA. The investigation was conducted to determine the aerodynamic characteristics of two scale ram air wings in support of air drop testing and full scale development of Advanced Recovery Systems for the Next Generation Space Transportation System. Two models were tested during this investigation. Both the primary test article, a 1/9 geometric scale model with wing area of 1200 square feet and secondary test article, a 1/36 geometric scale model with wing area of 300 square feet, had an aspect ratio of 3. The test results show that both models were statically stable about a model reference point at angles of attack from 2 to 10 degrees. The maximum lift-drag ratio varied between 2.9 and 2.4 for increasing wing loading.

  9. Advances in uncooled technology at BAE SYSTEMS

    NASA Astrophysics Data System (ADS)

    Backer, Brian S.; Kohin, Margaret; Leary, Arthur R.; Blackwell, Richard J.; Rumbaugh, Roy N.

    2003-09-01

    BAE SYSTEMS has made tremendous progress in uncooled technology and systems in the last year. In this paper we present performance results and imagery from our latest 640x480 and 320x240 small pixel focal plane arrays. Both were produced using submicron lithography and have achieved our lowest NETDs to date. Testing of the 320x240 devices has shown TNETDs of 30mK at F/1. Video imagery from our 640 x 480 uncooled camera installed in a POINTER Unattended Aerial Vehicle is also shown. In addition, we introduce our newest commercial imaging camera core, the SCC500 and show its vastly improved characteristics. Lastly, plans for future advancements are outlined.

  10. Lowest of AC-DC power output for electrostrictive polymers energy harvesting systems

    NASA Astrophysics Data System (ADS)

    Meddad, Mounir; Eddiai, Adil; Hajjaji, Abdelowahed; Guyomar, Daniel; Belkhiat, Saad; Boughaleb, Yahia; Chérif, Aida

    2013-11-01

    Advances in technology led to the development of electronic circuits and sensors with extremely low electricity consumption. At the same time, structural health monitoring, technology and intelligent integrated systems created a need for wireless sensors in hard to reach places in aerospace vehicles and large civil engineering structures. Powering sensors with energy harvesters eliminates the need to replace batteries on a regular basis. Scientists have been forced to search for new power source that are able to harvested energy from their surrounding environment (sunlight, temperature gradients etc.). Electrostrictive polymer belonging to the family of electro-active polymers, offer unique properties for the electromechanical transducer technology has been of particular interest over the last few years in order to replace conventional techniques such as those based on piezoelectric or electromagnetic, these materials are highly attractive for their low-density, with large strain capability that can be as high as two orders of magnitude greater than the striction-limited, rigid and fragile electroactive ceramics. Electrostrictive polymers sensors respond to vibration with an ac output signal, one of the most important objectives of the electronic interface is to realize the required AC-DC conversion. The goal of this paper is to design an active, high efficiency power doubler converter for electrostrictive polymers exclusively uses a fraction of the harvested energy to supply its active devices. The simulation results show that it is possible to obtain a maximum efficiency of the AC-DC converter equal to 80%. Premiliminary experimental measurements were performed and the results obtained are in good agreement with simulations.

  11. Advanced data management system architectures testbed

    NASA Technical Reports Server (NTRS)

    Grant, Terry

    1990-01-01

    The objective of the Architecture and Tools Testbed is to provide a working, experimental focus to the evolving automation applications for the Space Station Freedom data management system. Emphasis is on defining and refining real-world applications including the following: the validation of user needs; understanding system requirements and capabilities; and extending capabilities. The approach is to provide an open, distributed system of high performance workstations representing both the standard data processors and networks and advanced RISC-based processors and multiprocessor systems. The system provides a base from which to develop and evaluate new performance and risk management concepts and for sharing the results. Participants are given a common view of requirements and capability via: remote login to the testbed; standard, natural user interfaces to simulations and emulations; special attention to user manuals for all software tools; and E-mail communication. The testbed elements which instantiate the approach are briefly described including the workstations, the software simulation and monitoring tools, and performance and fault tolerance experiments.

  12. Final Report Advanced Quasioptical Launcher System

    SciTech Connect

    Jeffrey Neilson

    2010-04-30

    This program developed an analytical design tool for designing antenna and mirror systems to convert whispering gallery RF modes to Gaussian or HE11 modes. Whispering gallery modes are generated by gyrotrons used for electron cyclotron heating of fusion plasmas in tokamaks. These modes cannot be easily transmitted and must be converted to free space or waveguide modes compatible with transmission line systems.This program improved the capability of SURF3D/LOT, which was initially developed in a previous SBIR program. This suite of codes revolutionized quasi-optical launcher design, and this code, or equivalent codes, are now used worldwide. This program added functionality to SURF3D/LOT to allow creating of more compact launcher and mirror systems and provide direct coupling to corrugated waveguide within the vacuum envelope of the gyrotron. Analysis was also extended to include full-wave analysis of mirror transmission line systems. The code includes a graphical user interface and is available for advanced design of launcher systems.

  13. An Advanced Buffet Load Alleviation System

    NASA Technical Reports Server (NTRS)

    Burnham, Jay K.; Pitt, Dale M.; White, Edward V.; Henderson, Douglas A.; Moses, Robert W.

    2001-01-01

    This paper describes the development of an advanced buffet load alleviation (BLA) system that utilizes distributed piezoelectric actuators in conjunction with an active rudder to reduce the structural dynamic response of the F/A-18 aircraft vertical tails to buffet loads. The BLA system was defined analytically with a detailed finite-element-model of the tail structure and piezoelectric actuators. Oscillatory aerodynamics were included along with a buffet forcing function to complete the aeroservoelastic model of the tail with rudder control surface. Two single-input-single-output (SISO) controllers were designed, one for the active rudder and one for the active piezoelectric actuators. The results from the analytical open and closed loop simulations were used to predict the system performance. The objective of this BLA system is to extend the life of vertical tail structures and decrease their life-cycle costs. This system can be applied to other aircraft designs to address suppression of structural vibrations on military and commercial aircraft.

  14. Advanced CO2 Removal and Reduction System

    NASA Technical Reports Server (NTRS)

    Alptekin, Gokhan; Dubovik, Margarita; Copeland, Robert J.

    2011-01-01

    An advanced system for removing CO2 and H2O from cabin air, reducing the CO2, and returning the resulting O2 to the air is less massive than is a prior system that includes two assemblies . one for removal and one for reduction. Also, in this system, unlike in the prior system, there is no need to compress and temporarily store CO2. In this present system, removal and reduction take place within a single assembly, wherein removal is effected by use of an alkali sorbent and reduction is effected using a supply of H2 and Ru catalyst, by means of the Sabatier reaction, which is CO2 + 4H2 CH4 + O2. The assembly contains two fixed-bed reactors operating in alternation: At first, air is blown through the first bed, which absorbs CO2 and H2O. Once the first bed is saturated with CO2 and H2O, the flow of air is diverted through the second bed and the first bed is regenerated by supplying it with H2 for the Sabatier reaction. Initially, the H2 is heated to provide heat for the regeneration reaction, which is endothermic. In the later stages of regeneration, the Sabatier reaction, which is exothermic, supplies the heat for regeneration.

  15. ADVANCED TURBINE SYSTEM FEDERAL ASSISTANCE PROGRAM

    SciTech Connect

    Frank Macri

    2003-10-01

    Rolls-Royce Corporation has completed a cooperative agreement under Department of Energy (DOE) contract DE-FC21-96MC33066 in support of the Advanced Turbine Systems (ATS) program to stimulate industrial power generation markets. This DOE contract was performed during the period of October 1995 to December 2002. This final technical report, which is a program deliverable, describes all associated results obtained during Phases 3A and 3B of the contract. Rolls-Royce Corporation (formerly Allison Engine Company) initially focused on the design and development of a 10-megawatt (MW) high-efficiency industrial gas turbine engine/package concept (termed the 701-K) to meet the specific goals of the ATS program, which included single digit NOx emissions, increased plant efficiency, fuel flexibility, and reduced cost of power (i.e., $/kW). While a detailed design effort and associated component development were successfully accomplished for the 701-K engine, capable of achieving the stated ATS program goals, in 1999 Rolls-Royce changed its focus to developing advanced component technologies for product insertion that would modernize the current fleet of 501-K and 601-K industrial gas turbines. This effort would also help to establish commercial venues for suppliers and designers and assist in involving future advanced technologies in the field of gas turbine engine development. This strategy change was partly driven by the market requirements that suggested a low demand for a 10-MW aeroderivative industrial gas turbine, a change in corporate strategy for aeroderivative gas turbine engine development initiatives, and a consensus that a better return on investment (ROI) could be achieved under the ATS contract by focusing on product improvements and technology insertion for the existing Rolls-Royce small engine industrial gas turbine fleet.

  16. High Thermal Conductivity Polymer Matrix Composites (PMC) for Advanced Space Radiators

    NASA Technical Reports Server (NTRS)

    Shin, E. Eugene; Bowman, Cheryl; Beach, Duane

    2007-01-01

    High temperature polymer matrix composites (PMC) reinforced with high thermal conductivity (approx. 1000 W/mK) pitch-based carbon fibers are evaluated for a facesheet/fin structure of large space radiator systems. Significant weight reductions along with improved thermal performance, structural integrity and space durability toward its metallic counterparts were envisioned. Candidate commercial resin systems including Cyanate Esters, BMIs, and polyimide were selected based on thermal capabilities and processability. PMC laminates were designed to match the thermal expansion coefficient of various metal heat pipes or tubes. Large, but thin composite panels were successfully fabricated after optimizing cure conditions. Space durability of PMC with potential degradation mechanisms was assessed by simulated thermal aging tests in high vacuum, 1-3 x 10(exp -6) torr, at three temperatures, 227 C, 277 C, and 316 C for up to one year. Nanocomposites with vapor-grown carbon nano-fibers and exfoliated graphite flakes were attempted to improve thermal conductivity (TC) and microcracking resistance. Good quality nanocomposites were fabricated and evaluated for TC and durability including radiation resistance. TC was measured in both in-plan and thru-the-thickness directions, and the effects of microcracks on TC are also being evaluated. This paper will discuss the systematic experimental approaches, various performance-durability evaluations, and current subcomponent design and fabrication/manufacturing efforts.

  17. Structural materials challenges for advanced reactor systems

    NASA Astrophysics Data System (ADS)

    Yvon, P.; Carré, F.

    2009-03-01

    Key technologies for advanced nuclear systems encompass high temperature structural materials, fast neutron resistant core materials, and specific reactor and power conversion technologies (intermediate heat exchanger, turbo-machinery, high temperature electrolytic or thermo-chemical water splitting processes, etc.). The main requirements for the materials to be used in these reactor systems are dimensional stability under irradiation, whether under stress (irradiation creep or relaxation) or without stress (swelling, growth), an acceptable evolution under ageing of the mechanical properties (tensile strength, ductility, creep resistance, fracture toughness, resilience) and a good behavior in corrosive environments (reactor coolant or process fluid). Other criteria for the materials are their cost to fabricate and to assemble, and their composition could be optimized in order for instance to present low-activation (or rapid desactivation) features which facilitate maintenance and disposal. These requirements have to be met under normal operating conditions, as well as in incidental and accidental conditions. These challenging requirements imply that in most cases, the use of conventional nuclear materials is excluded, even after optimization and a new range of materials has to be developed and qualified for nuclear use. This paper gives a brief overview of various materials that are essential to establish advanced systems feasibility and performance for in pile and out of pile applications, such as ferritic/martensitic steels (9-12% Cr), nickel based alloys (Haynes 230, Inconel 617, etc.), oxide dispersion strengthened ferritic/martensitic steels, and ceramics (SiC, TiC, etc.). This article gives also an insight into the various natures of R&D needed on advanced materials, including fundamental research to investigate basic physical and chemical phenomena occurring in normal and accidental operating conditions, lab-scale tests to characterize candidate materials

  18. Advanced supersonic technology propulsion system study

    NASA Technical Reports Server (NTRS)

    Szeliga, R.; Allan, R. D.

    1974-01-01

    This study had the objectives of determining the most promising conventional and variable cycle engine types; the effect of design cruise Mach number (2.2, 2.7 and 3.2) on a commercial supersonic transport; effect of advanced engine technology on the choice of engine cycle; and effect of utilizing hydrogen as the engine fuel. The technology required for the engines was defined, and the levels of development to ensure availability of this technology in advanced aircraft propulsion systems were assessed. No clearcut best conventional or variable cycle engine was identified. The dry bypass turbojet and the duct burning turbofans were initially selected as the best conventional engines, but later results, utilizing augmentation at takeoff, added the mixed-flow augmented turbofan as a promising contender. The modulating air flow, three-rotor variable cycle engine identified the performance features desired from VCE concepts (elimination of inlet drag and reduction in afterbody drag), but was a very heavy and complex engine.

  19. Evaluation of polymer-housed distribution arresters for use on rural electric power systems

    SciTech Connect

    Mackevich, J. P.

    1994-03-01

    Users have converted to polymer-housed distribution surge arresters because of concerns over violent porcelain arrester failure. There is a false perception in the industry that polymer arresters are intrinsically fail-safe. It is proposed that there is a lack of understanding of the differences in failure mechanisms between porcelain and polymer arresters. Polymer arresters have unique design requirements to provide the desired reliability improvements. This paper suggests criteria for rural electric power system user evaluation of polymer arrester design and performance. Users are encouraged to participate in the standards writing process to facilitate changes beneficial to the industry.

  20. Tuning of electrostatic vs. depletion interaction in deciding the phase behavior of nanoparticle-polymer system

    SciTech Connect

    Kumar, Sugam Aswal, V. K.; Kohlbrecher, J.

    2015-06-24

    Nanoparticle-polymer system interestingly show a re-entrant phase behavior where charge stabilized silica nanoparticles (phase I) undergo particle clustering (phase II) and then back to individual particles (phase I) as a function of polymer concentration. Such phase behavior arises as a result of dominance of various interactions (i) nanoparticle-nanoparticle electrostatic repulsion (ii) polymer induced attractive depletion between nanoparticles and (iii) polymer-polymer repulsion, at different concentration regimes. Small-angle neutron scattering (SANS) has been used to study the evolution of interaction during this re-entrant phase behavior of nanoparticles by contrast-marching the polymer. The SANS data have been modeled using a two-Yukawa potential accounting for both attractive and repulsive parts of the interaction between nanoparticles. The degree of both of these parts has been separately tuned by varying the polymer concentration and ionic strength of the solution. Both of these parts are found to have long-range nature. At low polymer concentrations, the electrostatic repulsion dominates over the depletion attraction. The magnitude and the range of the depletion interaction increase with the polymer concentration leading to nanoparticle clustering. At higher polymer concentrations, the increased polymer-polymer repulsion reduces the strength of depletion leading to re-entrant phase behavior. The clusters formed under depletion attraction are found to have surface fractal morphology.

  1. Advanced kick detection systems improve HPHT operations

    SciTech Connect

    Harris, T.W.R.; Hendriks, P.; Surewaard, J.H.G.

    1995-09-01

    Many high-pressure, high-temperature (HPHT) wells are often characterized by the small margins that can exist between pore pressure and formation strength. Therefore, it is not surprising that kicks are far more likely to occur in HPHT wells and that a greater risk of internal blowout exists. The development and application of advanced kick detection systems for HPHT wells can help manage risks and improve drilling efficiency. Such systems enable earlier well shut-in, minimizing both the influx volume and the subsequent well bore pressures. This in turn lowers the risk, time and cost required for well control operations. Carefully considered application of these systems can also justify favorable economic benefits by optimization of the HPHT preliminary casing design. Minimizing kick volume can be important for the critical HPHT hole sections, where a reduced operating margin between pore pressure and fracture gradient exists, defining small design kick tolerance limits to permit safe drilling ahead to reach specified objectives. Kick detection for HPHT wells equivalent to less than 5 bbl of gas influx are often necessary to adequately minimize the risk of internal blowout and obtain the same levels of safety which are applied to conventional wells. This paper reviews these systems for both on-shore and off-shore operations.

  2. The Advanced Photon Source event system

    SciTech Connect

    Lenkszus, F.R.; Laird, R.

    1995-12-31

    The Advanced Photon Source, like many other facilities, requires a means of transmitting timing information to distributed control system 1/0 controllers. The APS event system provides the means of distributing medium resolution/accuracy timing events throughout the facility. It consists of VME event generators and event receivers which are interconnected with 10OMbit/sec fiber optic links at distances of up to 650m in either a star or a daisy chain configuration. The systems event throughput rate is 1OMevents/sec with a peak-to-peak timing jitter down to lOOns depending on the source of the event. It is integrated into the EPICS-based A.PS control system through record and device support. Event generators broadcast timing events over fiber optic links to event receivers which are programmed to decode specific events. Event generators generate events in response to external inputs, from internal programmable event sequence RAMS, and from VME bus writes. The event receivers can be programmed to generate both pulse and set/reset level outputs to synchronize hardware, and to generate interrupts to initiate EPICS record processing. In addition, each event receiver contains a time stamp counter which is used to provide synchronized time stamps to EPICS records.

  3. Advanced Extravehicular Protective System (AEPS) study

    NASA Technical Reports Server (NTRS)

    Williams, J. L.; Webbon, B. W.; Copeland, R. J.

    1972-01-01

    A summary is presented of Advanced Extravehicular Protective Systems (AEPS) for the future missions beyond Skylab in earth orbit, on the lunar surface, and on the Martian surface. The study concentrated on the origination of regenerable life support concepts for use in portable extravehicular protective systems, and included evaluation and comparison with expendable systems, and selection of life support subsystems. The study was conducted in two phases. In the first phase, subsystem concepts for performing life support functions in AEPS which are regenerable or partially regenerable were originated, and in addition, expendable subsystems were considered. Parametric data for each subsystem concept were evolved including subsystem weight and volume, power requirement, thermal control requirement; base regeneration equipment weight and volume, requirement. The second phase involved an evaluation of the impact of safety considerations involving redundant and/or backup systems on the selection of the regenerable life support subsystems. In addition, the impact of the space shuttle program on regenerable life support subsystem development was investigated.

  4. Advances in coiled-tubing operating systems

    SciTech Connect

    Sas-Jaworsky, A. II

    1997-06-01

    The expansion of coiled tubing (CT) applications into spooled flowlines, spooled completions, and CT drilling continues to grow at an accelerated rate. For many users within the oil and gas industry, the CT industry appears to be poised on the threshold of the next logical step in its evolution, the creation of a fully integrated operating system. However, for CT to evolve into such an operating system, the associated services must be robust and sufficiently reliable to support the needs of exploration, development drilling, completion, production management, and wellbore-retirement operations both technically and economically. The most critical hurdle to overcome in creating a CT-based operating system is a fundamental understanding of the operating scope and physical limitations of CT technology. The complete list of mechanisms required to advance CT into an operating system is large and complex. However, a few key issues (such as formal education, training, standardization, and increased levels of experience) can accelerate the transition. These factors are discussed.

  5. Characterization of advanced electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Ray, P. K.

    1982-01-01

    Characteristics of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. These are characterized by specific impulse, overall efficiency, input power, average thrust, power to average thrust ratio and average thrust to dry weight ratio. Several important physical characteristics such as dry system mass, accelerator length, bore size and current pulse requirement are also evaluated in appropriate cases. Only the ion engine can operate at a specific impulse beyond 2000 sec. Rail gun, MPD thruster and free radical thruster are currently characterized by low efficiencies. Mass drivers have the best performance characteristics in terms of overall efficiency, power to average thrust ratio and average thrust to dry weight ratio. But, they can only operate at low specific impulses due to large power requirements and are extremely long due to limitations of driving current. Mercury ion engines have the next best performance characteristics while operating at higher specific impulses. It is concluded that, overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

  6. Advanced Manned Launch System (AMLS) study

    NASA Technical Reports Server (NTRS)

    Ehrlich, Carl F., Jr.; Potts, Jack; Brown, Jerry; Schell, Ken; Manley, Mary; Chen, Irving; Earhart, Richard; Urrutia, Chuck; Randolph, Ray; Morris, Jim

    1992-01-01

    To assure national leadership in space operations and exploration in the future, NASA must be able to provide cost effective and operationally efficient space transportation. Several NASA studies and the joint NASA/DoD Space Transportation Architecture Studies (STAS) have shown the need for a multi-vehicle space transportation system with designs driven by enhanced operations and low costs. NASA is currently studying an advanced manned launch system (AMLS) approach to transport crew and cargo to the Space Station Freedom. Several single and multiple stage systems from air-breathing to all-rocket concepts are being examined in a series of studies potential replacements for the Space Shuttle launch system in the 2000-2010 time frame. Rockwell International Corporation, under contract to the NASA Langley Research Center, has analyzed a two-stage all-rocket concept to determine whether this class of vehicles is appropriate for the AMLS function. The results of the pre-phase A study are discussed.

  7. Towards more effective advanced drug delivery systems.

    PubMed

    Crommelin, Daan J A; Florence, Alexander T

    2013-09-15

    This position paper discusses progress made and to be made with so-called advanced drug delivery systems, particularly but not exclusively those in the nanometre domain. The paper has resulted from discussions with a number of international experts in the field who shared their views on aspects of the subject, from the nomenclature used for such systems, the sometimes overwrought claims made in the era of nanotechnology, the complex nature of targeting delivery systems to specific destinations in vivo, the need for setting standards for the choice and characterisation of cell lines used in in vitro studies, to attention to the manufacturability, stability and analytical profiling of systems and more relevant studies on toxicology. The historical background to the development of many systems is emphasised. So too is the stochastic nature of many of the steps to successful access to and action in targets. A lacuna in the field is the lack of availability of data on a variety of carrier systems using the same models in vitro and in vivo using standard controls. The paper asserts that greater emphasis must also be paid to the effective levels of active attained in target organs, for without such crucial data it will be difficult for many experimental systems to enter the clinic. This means the use of diagnostic/imaging technologies to monitor targeted drug delivery and stratify patient groups, identifying patients with optimum chances for successful therapy. Last, but not least, the critical importance of the development of science bases for regulatory policies, scientific platforms overseeing the field and new paradigms of financing are discussed. PMID:23415662

  8. Biomimetic optical system using polymer lenses with tunable focus

    NASA Astrophysics Data System (ADS)

    Liang, Dan; Xiang, Ke; Du, Jia-Wei; Yang, Jun-Nan; Wang, Xuan-Yin

    2014-10-01

    A biomimetic system using polymer lenses for the optical design and application is developed. The system mainly consisted of a bionic cornea lens, voice coil motor, compression ring, bionic crystalline lens, substrate, and CCD sensor. By controlling the current of the voice coil motor, we could change the motion of the compression ring to alter the curvature radius of the bionic crystalline lens, thus adjusting the focal length of the whole system. The integrated constructure of the optical system was presented, as well as the detailed description of the lens composition, material, and fabrication process. Images under different displacement loads were captured, the relationship among the curvature radius, observed back focal length, and predicted effective focal length was analyzed, and the spot diagram of the optical system was simulated using ZEMAX software. The focal length of the optical system ranged from 17.3 to 24.5 mm under a tiny displacement load from 0 to 0.14 mm. Besides, the images captured at different rotating angles presented almost identical patterns and the same image quality, which showed good robustness to the gravity. The biomimetic optical system is of interest to develop an integrated, low-cost, and stable imaging system.

  9. Advanced Aqueous Separation Systems for Actinide Partitioning

    SciTech Connect

    Nash, Kenneth L.; Clark, Sue; Meier, G Patrick; Alexandratos, Spiro; Paine, Robert; Hancock, Robert; Ensor, Dale

    2012-03-21

    One of the most challenging aspects of advanced processing of spent nuclear fuel is the need to isolate transuranium elements from fission product lanthanides. This project expanded the scope of earlier investigations of americium (Am) partitioning from the lanthanides with the synthesis of new separations materials and a centralized focus on radiochemical characterization of the separation systems that could be developed based on these new materials. The primary objective of this program was to explore alternative materials for actinide separations and to link the design of new reagents for actinide separations to characterizations based on actinide chemistry. In the predominant trivalent oxidation state, the chemistry of lanthanides overlaps substantially with that of the trivalent actinides and their mutual separation is quite challenging.

  10. Advanced Compact Holographic Data Storage System

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin; Zhou, Hanying; Reyes, George

    2000-01-01

    JPL, under current sponsorship from NASA Space Science and Earth Science Programs, is developing a high-density, nonvolatile and rad-hard Advanced Holographic Memory (AHM) system to enable large-capacity, high-speed, low power consumption, and read/write of data in a space environment. The entire read/write operation will be controlled with electro-optic mechanism without any moving parts. This CHDS will consist of laser diodes, photorefractive crystal, spatial light modulator, photodetector array, and I/O electronic interface. In operation, pages of information would be recorded and retrieved with random access and highspeed. The nonvolatile, rad-hard characteristics of the holographic memory will provide a revolutionary memory technology to enhance mission capabilities for all NASA's Earth Science Mission. In this paper, recent technology progress in developing this CHDS at JPL will be presented.

  11. Advanced U. S. military aircraft battery systems

    SciTech Connect

    Flake, R.A.; Eskra, M.D.

    1990-01-01

    While most USAF aircraft currently use vented Ni-Cd for dc electrical power and emergency power, as well as the powering of lights and instruments prior to engine starting, these batteries have high maintenance requirements, low reliability, and no built-in testing capability with which to check battery health prior to flight. The USAF Wright R D Center accordingly initiated its Advanced Maintenance-Free NiCd Battery System development program in 1986, in order to develop a sealed Ni-Cd battery which would remain maintenance-free over a period of three years. Attention is being given to a high power bipolar battery design in which there are no individual cell cases or cell interconnects.

  12. ADVANCED GAS TURBINE SYSTEMS RESEARCH PROGRAM

    SciTech Connect

    Lawrence P. Golan

    2003-05-01

    The quarterly activities of the Advanced Gas Turbine Systems Research (AGTSR) program are described in this quarterly report. As this program administers research, we have included all program activity herein within the past quarter as dated. More specific research progress reports are provided weekly at the request of the AGTSR COR and are being sent to NETL As for the administration of this program, items worthy of note are presented in extended bullet format following the appropriate heading. No new memberships, workshops, research projects, internships, faculty fellowships or special studies were initiated during this reporting period. Contract completion is set for June 30, 2003. During the report period, nine subcontractor reports were received (5 final reports and 4 semi-annual reports). The report technology distribution is as follows: 3--aero-heat transfer, 2--combustion and 4--materials. AGTSR continues to project that it will under spend DOE obligated funds by approximately $329K.

  13. A New Class Of Bilevel And Mono-Level Positive Resist Systems Based On A Chemically Stable Imide Polymer

    NASA Astrophysics Data System (ADS)

    Legenza, M. W.; Vidusek, D. A.; de Grandpre, M.

    1985-04-01

    A new resin system, comprising a thermoplastic polymer backbone with chemically stable imide functionality, has been adapted for use in three different positive resist product types. These include an advanced bilayer system, a near, mid and deep UV monolevel resist; and an antireflective coating. The key features of the imide polymer system which are utilized for the new resist products are: 1. Novolac-like solubility in aqueous base. This property allows formulation of resists, including the planarizing layer of a bilevel system, with conventional types of positive resist photoactive compounds and aqueous base developers, unlike the situation with PMMA which is not base soluble. 2. Transparency to wavelengths above 260nm. This permits use of the polymer as the matrix for systems which utilize mid and deep UV exposure, including the planarizing layer for a bilevel system and mid and deep UV monolayer resists. This is in contrast to novolac resin wHch absorbs strongly in the deep UV region. 3. Insolubility in solvents used for conventional positive resists. This property is critical to use of the resin in planarizing layers of bilevel systems, including antirefiective coatings. It eliminates the intermixing problems which represent a major problem in conventional PMMA bilevel systems. 4. High Tg (185°C). This value is about 80°C higher than that of PMMA and allows higher temperature processing without pattern distortion. 5. Chemical stability and plasma resistance. Unlike conventional reactive polyimide resins the subject polymer is chemically unreactive and is stable to temperatures above 300°C. Further, the polymer has significantly greater resistance to plasma than does PMMA.

  14. Conducting polymer actuators: From basic concepts to proprioceptive systems

    NASA Astrophysics Data System (ADS)

    Martinez Gil, Jose Gabriel

    Designers and engineers have been dreaming for decades of motors sensing, by themselves, working and surrounding conditions, as biological muscles do originating proprioception. Here bilayer full polymeric artificial muscles were checked up to very high cathodic potential limits (-2.5 V) in aqueous solution by cyclic voltammetry. The electrochemical driven exchange of ions from the conducting polymer film, and the concomitant Faradaic bending movement of the muscle, takes place in the full studied potential range. The presence of trapped counterion after deep reduction was corroborated by EDX determinations giving quite high electronic conductivity to the device. The large bending movement was used as a tool to quantify the amount of water exchanged per reaction unit (exchanged electron or ion). The potential evolutions of self-supported films of conducting polymers or conducting polymers (polypyrrole, polyaniline) coating different microfibers, during its oxidation/reduction senses working mechanical, thermal, chemical or electrical variables. The evolution of the muscle potential from electrochemical artificial muscles based on electroactive materials such as intrinsically conducting polymers and driven by constant currents senses, while working, any variation of the mechanical (trailed mass, obstacles, pressure, strain or stress), thermal or chemical conditions of work. One physically uniform artificial muscle includes one electrochemical motor and several sensors working simultaneously under the same driving reaction. Actuating (current and charge) and sensing (potential and energy) magnitudes are present, simultaneously, in the only two connecting wires and can be read by the computer at any time. From basic polymeric, mechanical and electrochemical principles a physicochemical equation describing artificial proprioception has been developed. It includes and describes, simultaneously, the evolution of the muscle potential during actuation as a function of the

  15. Qualitative and quantitative methods to determine miscibility in amorphous drug-polymer systems.

    PubMed

    Meng, Fan; Dave, Vivek; Chauhan, Harsh

    2015-09-18

    Amorphous drug-polymer systems or amorphous solid dispersions are commonly used in pharmaceutical industry to enhance the solubility of compounds with poor aqueous solubility. The degree of miscibility between drug and polymer is important both for solubility enhancement as well as for the formation of a physically stable amorphous system. Calculation of solubility parameters, Computational data mining, Tg measurements by DSC and Raman mapping are established traditional methods used to qualitatively detect the drug-polymer miscibility. Calculation of Flory-Huggins interaction parameter, computational analysis of X-Ray Diffraction (XRD) data, solid state Nuclear Magnetic Resonance (NMR) spectroscopy and Atomic Forced Microscopy (AFM) have been recently developed to quantitatively determine the miscibility in amorphous drug-polymer systems. This brief review introduces and compiles these qualitative and quantitative methods employed in the evaluation of drug-polymer miscibility. Combination of these techniques can provide deeper insights into the true miscibility of the drug-polymer systems. PMID:26006307

  16. Advanced integrated WDM system for POF communication

    NASA Astrophysics Data System (ADS)

    Haupt, M.; Fischer, U. H. P.

    2009-01-01

    Polymer Optical Fibres (POFs) show clear advantages compared to copper and glass fibres. In essence, POFs are inexpensive, space-saving and not susceptible to electromagnetic interference. Thus, the usage of POFs have become a reasonable alternative in short distance data communication. Today, POFs are applied in a wide number of applications due to these specific advantages. These applications include automotive communication systems and in-house-networks. State-of-the-art is to transmit data with only one channel over POF, this limits the bandwidth. To solve this problem, an integrated MUX/DEMUX-element for WDM over POF is designed and developed to use multiple channels. This integration leads to low costs, therefore this component is suitable for mass market applications. The fundamental idea is to separate the chromatic parts of the light in its monochromatic components by means of a grating based on an aspheric mirror. Due to the high NA of the POF the setup has to be designed in a 3D-approach. Therefore this setup cannot be compared with the planar solutions available on market, they would result high losses in the 3rd dimension. To achieve a fast and optimized design an optical simulation program is used. Particular attention has to be paid to the design of the POF as a light source in the simulation program and the optimisation of the grating. The following realization of the demultiplexer is planed to be done with injection molding. This technology offers easy and very economical processing. These advantages make this technology first choice for optical components in the low-cost array.

  17. Energy Systems Integration: NREL + Advanced Energy (Fact Sheet)

    SciTech Connect

    Not Available

    2015-02-01

    This fact sheet describes the collaboration between NREL and Advanced Energy Industries at the ESIF to test its advanced photovoltaic inverter technology with the ESIF's power hardware-in-the-loop system and megawatt-scale grid simulators.

  18. Alisse : Advanced life support system evaluator

    NASA Astrophysics Data System (ADS)

    Brunet, Jean; Gerbi, Olivier; André, Philippe; Davin, Elisabeth; Avezuela Rodriguez, Raul; Carbonero, Fernando; Soumalainen, Emilia; Lasseur, Christophe

    Long duration missions, such as the establishment of permanent bases on the lunar surface or the travel to Mars, require such an amount of life support consumables (e.g. food, water and oxygen) that direct supply or re-supply from Earth is not an option anymore. Regenerative Life Support Systems are therefore necessary to sustain long-term manned space mission to increase recycling rates and so reduce the launched mass. The architecture of an Environmental Controlled Life Support System widely depends on the mission scenario. Even for a given mission scenario, different architectures could be envisaged which need to be evaluated and compared with appropriate tools. As these evaluation and comparison, based on the single criterion of Equivalent System Mass, was not considered com-prehensive enough, ESA is developing a multi-criteria evaluation tool: ALISSE (Advanced Life Support System Evaluator). The main objective of ALISSE, and of the work presented here, is the definition and implemen-tation of a metrics system, addressing the complexity of any ECLSS along its Life Cycle phases. A multi-dimensional and multi-criteria (i.e. mass, energy, efficiency, risk to human, reliability, crew time, sustainability, life cycle cost) approach is proposed through the development of a computing support platform. Each criterion being interrelated with the others, a model based system approach is used. ALISSE is expected to provide significant inputs to the ESA Concurrent Design Facility and, as a consequence, to be a highly valuable tool for decision process linked to any manned space mission. Full contact detail for the contact author : Jean Brunet Sherpa Engineering General Manager Phone : 0033(0)608097480 j.brunet@sherpa-eng.com

  19. Space Shuttle Upgrades Advanced Hydraulic Power System

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Three Auxiliary Power Units (APU) on the Space Shuttle Orbiter each provide 145 hp shaft power to a hydraulic pump which outputs 3000 psi hydraulic fluid to 41 hydraulic actuators. A hydrazine fuel powered APU utilized throughout the Shuttle program has undergone many improvements, but concerns remain with flight safety, operational cost, critical failure modes, and hydrazine related hazards. The advanced hydraulic power system (AHPS), also known as the electric APU, is being evaluated as an upgrade to replace the hydrazine APU. The AHPS replaces the high-speed turbine and hydrazine fuel supply system with a battery power supply and electric motor/pump that converts 300 volt electrical power to 3000 psi hydraulic power. AHPS upgrade benefits include elimination of toxic hydrazine propellant to improve flight safety, reduction in hazardous ground processing operations, and improved reliability. Development of this upgrade provides many interesting challenges and includes development of four hardware elements that comprise the AHPS system: Battery - The battery provides a high voltage supply of power using lithium ion cells. This is a large battery that must provide 28 kilowatt hours of energy over 99 minutes of operation at 300 volts with a peak power of 130 kilowatts for three seconds. High Voltage Power Distribution and Control (PD&C) - The PD&C distributes electric power from the battery to the EHDU. This 300 volt system includes wiring and components necessary to distribute power and provide fault current protection. Electro-Hydraulic Drive Unit (EHDU) - The EHDU converts electric input power to hydraulic output power. The EHDU must provide over 90 kilowatts of stable, output hydraulic power at 3000 psi with high efficiency and rapid response time. Cooling System - The cooling system provides thermal control of the Orbiter hydraulic fluid and EHDU electronic components. Symposium presentation will provide an overview of the AHPS upgrade, descriptions of the four

  20. Advanced Stirling conversion systems for terrestrial applications

    NASA Technical Reports Server (NTRS)

    Shaltens, R. K.

    1987-01-01

    Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories (SNLA) is developing heat engines for terrestrial Solar Distributed Heat Receivers. SNLA has identified the Stirling to be one of the most promising candidates for the terrestrial applications. The free-piston Stirling engine (FPSE) has the potential to meet the DOE goals for both performance and cost. The National Aeronautics and Space Administration (NASA) Lewis Research Center (LeRC) is conducting free-piston Stirling activities which are directed toward a dynamic power source for space applications. Space power system requirements include high efficiency, very long life, high reliability and low vibration. The FPSE has the potential for future high power space conversion systems, either solar or nuclear. Generic free-piston technology is currently being developed by LeRC for DOE/ORNL for use with a residential heat pump under an Interagency Agreement. Since 1983, the SP-100 Program (DOD/NASA/DOE) is developing dynamic power sources for space. Although both applications (heat pump and space power) appear to be quite different, their requirements complement each other. A cooperative Interagency Agreement (IAA) was signed in 1985 with NASA Lewis to provide technical management for an Advanced Stirling Conversion System (ASCS) for SNLA. Conceptual design(s) using a free-piston Stirling (FPSE), and a heat pipe will be discussed. The ASCS will be designed using technology which can reasonably be expected to be available in the 1980's.

  1. Advanced continuous cultivation methods for systems microbiology.

    PubMed

    Adamberg, Kaarel; Valgepea, Kaspar; Vilu, Raivo

    2015-09-01

    Increasing the throughput of systems biology-based experimental characterization of in silico-designed strains has great potential for accelerating the development of cell factories. For this, analysis of metabolism in the steady state is essential as only this enables the unequivocal definition of the physiological state of cells, which is needed for the complete description and in silico reconstruction of their phenotypes. In this review, we show that for a systems microbiology approach, high-resolution characterization of metabolism in the steady state--growth space analysis (GSA)--can be achieved by using advanced continuous cultivation methods termed changestats. In changestats, an environmental parameter is continuously changed at a constant rate within one experiment whilst maintaining cells in the physiological steady state similar to chemostats. This increases the resolution and throughput of GSA compared with chemostats, and, moreover, enables following of the dynamics of metabolism and detection of metabolic switch-points and optimal growth conditions. We also describe the concept, challenge and necessary criteria of the systematic analysis of steady-state metabolism. Finally, we propose that such systematic characterization of the steady-state growth space of cells using changestats has value not only for fundamental studies of metabolism, but also for systems biology-based metabolic engineering of cell factories. PMID:26220303

  2. Advanced Stirling conversion systems for terrestrial applications

    SciTech Connect

    Shaltens, R.K.

    1987-01-01

    Sandia National Laboratories (SNLA) is developing heat engines for terrestrial Solar distributed Heat Receivers. SNLA has identified the Stirling to be one of the most promising candidates for the terrestrial applications. The free-piston Stirling engine (FPSE) has the potential to meet the DOE goals for both performance and cost. Free-piston Stirling activities which are directed toward a dynamic power source for the space application are being conducted. Space power system requirements include high efficiency, very long life, high reliability and low vibration. The FPSE has the potential for future high power space conversion systems, either solar or nuclear powered. Generic free-piston technology is currently being developed for use with a residential heat pump under an Interagency Agreement. Also, an overview is presented of proposed conceptual designs for the Advanced Stirling Conversion System (ASCS) using a free-piston Stirling engine and a liquid metal heat pipe receiver. Power extraction includes both a linear alternator and hydraulic output capable of delivering approximately 25 kW of electrical power to the electric utility grid. Target cost of the engine/alternator is 300 dollars per kilowatt at a manufacturing rate of 10,000 units per year. The design life of the ASCS is 60,000 h (30 y) with an engine overhaul at 40,000 h (20 y). Also discussed are the key features and characteristics of the ASCS conceptual designs.

  3. Payload deployment systems and advanced manipulators

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The results of discussions on future development of avionics to support payload deployment systems and advanced manipulators are discussed. The discussions summarized here were held during the Space Transportation Avionics Technology Symposium in Williamsburg, Virginia on November 7 to 9, 1989. Symposium participants agreed that this subpanel would have benefitted from more participation by users. It was suggested that inputs from Shuttle payload users should be incorporated, either by direct discussions with users or by incorporating comments from users as kept by Payload Accommodations. The Jet Propulsion Laboratory (JPL), Goddard, and Langley, as builders of payloads, and the Space Station Utilization Office could also provide useful inputs. Other potential users for future systems should also be identified as early as possible to determine what they anticipate their needs to be. Symposium participants also recognized that payload deployment is normally not a safety critical area, and as such, is vulnerable to budget cuts that defer costs from development to operations. This does give opportunities for upgrades of operational systems, but these must be very cost effective to compete with vehicle requirements that enhance safety or increase lifetime.

  4. Advanced Liquid Natural Gas Onboard Storage System

    SciTech Connect

    Greg Harper; Charles Powars

    2003-10-31

    Cummins Westport Incorporated (CWI) has designed and developed a liquefied natural gas (LNG) vehicle fuel system that includes a reciprocating pump with the cold end submerged in LNG contained in a vacuum-jacketed tank. This system was tested and analyzed under the U.S. Department of Energy (DOE) Advanced LNG Onboard Storage System (ALOSS) program. The pumped LNG fuel system developed by CWI and tested under the ALOSS program is a high-pressure system designed for application on Class 8 trucks powered by CWI's ISX G engine, which employs high-pressure direct injection (HPDI) technology. A general ALOSS program objective was to demonstrate the feasibility and advantages of a pumped LNG fuel system relative to on-vehicle fuel systems that require the LNG to be ''conditioned'' to saturation pressures that exceeds the engine fuel pressure requirements. These advantages include the capability to store more fuel mass in given-size vehicle and station tanks, and simpler lower-cost LNG refueling stations that do not require conditioning equipment. Pumped LNG vehicle fuel systems are an alternative to conditioned LNG systems for spark-ignition natural gas and port-injection dual-fuel engines (which typically require about 100 psi), and they are required for HPDI engines (which require over 3,000 psi). The ALOSS program demonstrated the feasibility of a pumped LNG vehicle fuel system and the advantages of this design relative to systems that require conditioning the LNG to a saturation pressure exceeding the engine fuel pressure requirement. LNG tanks mounted on test carts and the CWI engineering truck were repeatedly filled with LNG saturated at 20 to 30 psig. More fuel mass was stored in the vehicle tanks as well as the station tank, and no conditioning equipment was required at the fueling station. The ALOSS program also demonstrated the general viability and specific performance of the CWI pumped LNG fuel system design. The system tested as part of this program is

  5. Atomic step-and-terrace surface of polyimide sheet for advanced polymer substrate engineering.

    PubMed

    Tan, G; Shimada, K; Nozawa, Y; Kaneko, S; Urakami, T; Koyama, K; Komura, M; Matsuda, A; Yoshimoto, M

    2016-07-22

    Typical thermostable and flexible polyimide polymers exhibit many excellent properties such as strong mechanical and chemical resistance. However, in contrast to single-crystal substrates like silicon or sapphire, polymers mostly display disordered and rough surfaces, which may result in instability and degradation of the interfaces between thin films and polymer substrates. As a step toward the development of next-generation polymer substrates, we here report single-atom-layer imprinting onto the polyimide sheets, resulting in an ultrasmooth 0.3 nm high atomic step-and-terrace surface on the polyimides. The ultrasmooth polymer substrates are expected to be applied to the fabrication of nanostructures such as superlattices, nanowires, or quantum dots in nanoscale-controlled electronic devices. We fabricate smooth and atomically stepped indium tin oxide transparent conducting oxide thin films on the imprinted polyimide sheets for future use in organic-based optoelectronic devices processed with nanoscale precision. Furthermore, toward 2D polymer substrate nanoengineering, we demonstrate nanoscale letter writing on the atomic step-and-terrace polyimide surface via atomic force microscopy probe scratching. PMID:27284690

  6. Atomic step-and-terrace surface of polyimide sheet for advanced polymer substrate engineering

    NASA Astrophysics Data System (ADS)

    Tan, G.; Shimada, K.; Nozawa, Y.; Kaneko, S.; Urakami, T.; Koyama, K.; Komura, M.; Matsuda, A.; Yoshimoto, M.

    2016-07-01

    Typical thermostable and flexible polyimide polymers exhibit many excellent properties such as strong mechanical and chemical resistance. However, in contrast to single-crystal substrates like silicon or sapphire, polymers mostly display disordered and rough surfaces, which may result in instability and degradation of the interfaces between thin films and polymer substrates. As a step toward the development of next-generation polymer substrates, we here report single-atom-layer imprinting onto the polyimide sheets, resulting in an ultrasmooth 0.3 nm high atomic step-and-terrace surface on the polyimides. The ultrasmooth polymer substrates are expected to be applied to the fabrication of nanostructures such as superlattices, nanowires, or quantum dots in nanoscale-controlled electronic devices. We fabricate smooth and atomically stepped indium tin oxide transparent conducting oxide thin films on the imprinted polyimide sheets for future use in organic-based optoelectronic devices processed with nanoscale precision. Furthermore, toward 2D polymer substrate nanoengineering, we demonstrate nanoscale letter writing on the atomic step-and-terrace polyimide surface via atomic force microscopy probe scratching.

  7. Nanoscale Control of Polymer Assembly on a Synthetic Catalyst-Bilayer System.

    PubMed

    Gorgoll, Ricardo M; Harano, Koji; Nakamura, Eiichi

    2016-08-01

    The use of the interior of self-assembled membrane as a template for polymer synthesis and assembly has long attracted the interest of chemists. However, it is difficult to utilize a lipid membrane as a chemical reactor for controlled assembly for polymers because lipid membrane is easily destabilized by loading of extraneous molecules. We found that a several-nanometer-thick bilayer vesicle made by self-assembly of an organic fullerene amphiphile doped with a metathesis catalyst serves as a nanosized chemical reactor in water, where a polymer is synthesized and assembled, depending on the affinity of the growing polymer to the organic groups on the amphiphile. This catalyst-bilayer system can thus control supramolecular assembly of the ester-functionalized polymer product into different nanoscale structures: a nanoparticle made of a single polymer chain and a nanocapsule made of several tens of polymer chains. PMID:27404736

  8. Advanced Air Data Systems for Commercial Aircraft

    NASA Technical Reports Server (NTRS)

    2006-01-01

    It is possible to get a crude estimate of wind speed and direction while driving a car at night in the rain, with the motion of the raindrop reflections in the headlights providing clues about the wind. The clues are difficult to interpret, though, because of the relative motions of ground, car, air, and raindrops. More subtle interpretation is possible if the rain is replaced by fog, because the tiny droplets would follow the swirling currents of air around an illuminated object, like, for example, a walking pedestrian. Microscopic particles in the air (aerosols) are better for helping make assessments of the wind, and reflective air molecules are best of all, providing the most refined measurements. It takes a bright light to penetrate fog, so it is easy to understand how other factors, like replacing the headlights with the intensity of a searchlight, can be advantageous. This is the basic principle behind a lidar system. While a radar system transmits a pulse of radiofrequency energy and interprets the received reflections, a lidar system works in a similar fashion, substituting a near-optical laser pulse. The technique allows the measurement of relative positions and velocities between the transmitter and the air, which allows measurements of relative wind and of air temperature (because temperature is associated with high-frequency random motions on a molecular level). NASA, as well as the National Oceanic and Atmospheric Administration (NOAA), have interests in this advanced lidar technology, as much of their explorative research requires the ability to measure winds and turbulent regions within the atmosphere. Lidar also shows promise for providing warning of turbulent regions within the National Airspace System to allow commercial aircraft to avoid encounters with turbulence and thereby increase the safety of the traveling public. Both agencies currently employ lidar and optical sensing for a variety of weather-related research projects, such as analyzing

  9. Advanced information processing system: Input/output system services

    NASA Technical Reports Server (NTRS)

    Masotto, Tom; Alger, Linda

    1989-01-01

    The functional requirements and detailed specifications for the Input/Output (I/O) Systems Services of the Advanced Information Processing System (AIPS) are discussed. The introductory section is provided to outline the overall architecture and functional requirements of the AIPS system. Section 1.1 gives a brief overview of the AIPS architecture as well as a detailed description of the AIPS fault tolerant network architecture, while section 1.2 provides an introduction to the AIPS systems software. Sections 2 and 3 describe the functional requirements and design and detailed specifications of the I/O User Interface and Communications Management modules of the I/O System Services, respectively. Section 4 illustrates the use of the I/O System Services, while Section 5 concludes with a summary of results and suggestions for future work in this area.

  10. Advanced space transportation systems, BARGOUZIN booster

    NASA Astrophysics Data System (ADS)

    Prampolini, Marco; Louaas, Eric; Prel, Yves; Kostromin, Sergey; Panichkin, Nickolay; Sumin, Yuriy; Osin, Mikhail; Iranzo-Greus, David; Rigault, Michel; Beaurain, André; Couteau, Jean-Noël

    2008-07-01

    In the framework of Advanced Space Transportation Systems Studies sponsored by CNES in 2006, a study called "BARGOUZIN" was performed by a joint team led by ASTRIUM ST and TSNIIMASH. Beyond these leaders, the team comprised MOLNIYA, DASSAULT AVIATION and SNECMA as subcontractors. The "BARGOUZIN" concept is a liquid fuelled fly-back booster (LFBB), mounted on the ARIANE 5 central core stage in place of the current solid rocket booster. The main originality of the concept lies in the fact that the "BARGOUZIN" features a cluster of VULCAIN II engines, similar to the one mounted on the central core stage of ARIANE 5. An astute permutation strategy, between the booster engines and central core engine is expected to lead to significant cost reductions. The following aspects were addressed during the preliminary system study: engine number per booster trade-off/abort scenario analysis, aerodynamic consolidation, engine reliability, ascent controllability, ground interfaces separation sequence analysis, programmatics. These topics will be briefly presented and synthesized in this paper, giving an overview of the credibility of the concept.

  11. Hollow fiber membrane systems for advanced life support systems

    NASA Technical Reports Server (NTRS)

    Roebelen, G. J., Jr.; Lysaght, M. J.

    1976-01-01

    The practicability of utilizing hollow fiber membranes in vehicular and portable life support system applications is described. A preliminary screening of potential advanced life support applications resulted in the selection of five applications for feasibility study and testing. As a result of the feasibility study and testing, three applications, heat rejection, deaeration, and bacteria filtration, were chosen for breadboard development testing; breadboard hardware was manufactured and tested, and the physical properties of the hollow fiber membrane assemblies are characterized.

  12. ArF photoresist system using alicyclic polymer

    NASA Astrophysics Data System (ADS)

    Park, Joo Hyeon; Kim, Seong-Ju; Park, Sun-Yi; Lee, Hosull; Jung, Jae Chang; Bok, Cheol-Kyu; Baik, Ki-Ho

    1997-07-01

    We have developed a chemically amplified photoresist for use in ArF lithography based on alicyclic polymer. 3- Bicyclo(2,2,1)hept-2-yl-3-(2-methyl allyoxy)-propionic acid tert-butyl ester (BHPE) was prepared as a new kind of protected acid-labile monomer. Terpolymer, poly(BHPE-NBO-MAL), was prepared with BHPE, 5-norbornen-2-ol (NBO), and maleic anhydride (MAL) monomers by radical polymerization. Photoresist of poly(BHPE-NBO-MAL) displayed good adhesion, dry-etch resistance, and development. As a result, we obtained 0.16 micrometer line-and-space positive patterns with 2.38 wt% TMAH aqueous solution using an ArF exposure system.

  13. Session: CSP Advanced Systems: Optical Materials (Presentation)

    SciTech Connect

    Kennedy, C.

    2008-04-01

    The Optical Materials project description is to characterize advanced reflector, perform accelerated and outdoor testing of commercial and experimental reflector materials, and provide industry support.

  14. Electrically switchable polymer liquid crystal and polymer birefringent flake in fluid host systems and optical devices utilizing same

    SciTech Connect

    Marshall, Kenneth L.; Kosc, Tanya Z.; Jacobs, Stephen D.; Faris, Sadeg M.; Li, Le

    2003-12-16

    Flakes or platelets of polymer liquid crystals (PLC) or other birefringent polymers (BP) suspended in a fluid host medium constitute a system that can function as the active element in an electrically switchable optical device when the suspension is either contained between a pair of rigid substrates bearing transparent conductive coatings or dispersed as microcapsules within the body of a flexible host polymer. Optical properties of these flake materials include large effective optical path length, different polarization states and high angular sensitivity in their selective reflection or birefringence. The flakes or platelets of these devices need only a 3-20.degree. rotation about the normal to the cell surface to achieve switching characteristics obtainable with prior devices using particle rotation or translation.

  15. Mobile Monolith Polymer Elements For Flow Control In Microfluidic Systems

    DOEpatents

    Hasselbrink, Jr., Ernest F.; Rehm, Jason E.; Shepodd, Timothy J.; Kirby, Brian J.

    2006-01-24

    A cast-in-place and lithographically shaped mobile, monolithic polymer element for fluid flow control in microfluidic devices and method of manufacture. Microfluid flow control devices, or microvalves that provide for control of fluid or ionic current flow can be made incorporating a cast-in-place, mobile monolithic polymer element, disposed within a microchannel, and driven by fluid pressure (either liquid or gas) against a retaining or sealing surface. The polymer elements are made by the application of lithographic methods to monomer mixtures formulated in such a way that the polymer will not bond to microchannel walls. The polymer elements can seal against pressures greater than 5000 psi, and have a response time on the order of milliseconds. By the use of energetic radiation it is possible to depolymerize selected regions of the polymer element to form shapes that cannot be produced by conventional lithographic patterning and would be impossible to machine.

  16. Advanced Technology Lifecycle Analysis System (ATLAS)

    NASA Technical Reports Server (NTRS)

    O'Neil, Daniel A.; Mankins, John C.

    2004-01-01

    Developing credible mass and cost estimates for space exploration and development architectures require multidisciplinary analysis based on physics calculations, and parametric estimates derived from historical systems. Within the National Aeronautics and Space Administration (NASA), concurrent engineering environment (CEE) activities integrate discipline oriented analysis tools through a computer network and accumulate the results of a multidisciplinary analysis team via a centralized database or spreadsheet Each minute of a design and analysis study within a concurrent engineering environment is expensive due the size of the team and supporting equipment The Advanced Technology Lifecycle Analysis System (ATLAS) reduces the cost of architecture analysis by capturing the knowledge of discipline experts into system oriented spreadsheet models. A framework with a user interface presents a library of system models to an architecture analyst. The analyst selects models of launchers, in-space transportation systems, and excursion vehicles, as well as space and surface infrastructure such as propellant depots, habitats, and solar power satellites. After assembling the architecture from the selected models, the analyst can create a campaign comprised of missions spanning several years. The ATLAS controller passes analyst specified parameters to the models and data among the models. An integrator workbook calls a history based parametric analysis cost model to determine the costs. Also, the integrator estimates the flight rates, launched masses, and architecture benefits over the years of the campaign. An accumulator workbook presents the analytical results in a series of bar graphs. In no way does ATLAS compete with a CEE; instead, ATLAS complements a CEE by ensuring that the time of the experts is well spent Using ATLAS, an architecture analyst can perform technology sensitivity analysis, study many scenarios, and see the impact of design decisions. When the analyst is

  17. The advanced flame quality indicator system

    SciTech Connect

    Oman, R.; Rossi, M.J.; Calia, V.S.; Davis, F.L.; Rudin, A.

    1997-09-01

    By combining oil tank monitoring, systems diagnostics and flame quality monitoring in an affordable system that communicates directly with dealers by telephone modem, Insight Technologies offers new revenue opportunities and the capability for a new order of customer relations to oil dealers. With co-sponsorship from New York State Energy Research and Development Authority, we have incorporated several valuable functions to a new product based on the original Flame Quality Indicator concept licensed from the US DOE`s Brookhaven National Laboratory. The new system is the Advanced Flame Quality Indicator, or AFQI. As before, the AFQI monitors and reports the intensity of the burner flame relative to a calibration established when the burner is set up at AFQI installation. Repairs or adjustments are summoned by late-night outgoing telephone calls when limits are exceeded in either direction, indicating an impending contamination or other malfunction. A independently, a pressure transducer for monitoring oil tank level and filter condition, safety lockout alarms and a temperature monitor; all reporting automatically at instructed intervals via an on-board modem to a central station PC computer (CSC). Firmware on each AFQI unit and Insight-supplied software on the CSC automatically interact to maintain a customer database for an oil dealer, an OEM, or a regional service contractor. In addition to ensuring continuously clean and efficient operation, the AFQI offers the oil industry a new set of immediate payoffs, among which are reduced outages and emergency service calls, shorter service calls from cleaner operation, larger oil delivery drops, the opportunity to stretch service intervals to as along as three years in some cases, new selling features to keep and attract customers, and greatly enhanced customer contact, quality and reliability.

  18. 75 FR 66319 - State Systems Advance Planning Document (APD) Process

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-28

    ... HUMAN SERVICES 45 CFR Part 95 RIN 0970-AC33 State Systems Advance Planning Document (APD) Process AGENCY... Health and Human Services (HHS). ACTION: Final rule. SUMMARY: The Advance Planning Document (APD) process... support programs for children and families. The Advance Planning Document (APD) process governs...

  19. A system concept for an advanced vehicle control system

    SciTech Connect

    Mackey, D.E.; Mackey, W.F. Jr.; Mackey, W.F.

    1996-12-01

    This paper explores a system concept for an Advanced Vehicle Control System (AVCS). The progression of highway design and construction has resulted from an evolution of technologies, inventions, organizational creations, and legislative acts supporting the development of a national interstate transportation system. Until now, highway design and construction has been the domain of civil engineers concerned with highway structures, materials loading, traffic patterns, and supporting facilities. However, the growing need for intelligent vehicle-highway systems (IVHS) requires that traditional civil engineering disciplines be integrated with computers, communications, and eventually fully automated vehicles. This paper`s thesis suggests that the complex highway transportation of the late 20th century and the 21st century can benefit from the collaboration of systems engineers and civil engineers. This paper identifies and prototypes an AVCS concept with roadside computers controlling the lateral and longitudinal movements of a vehicle.

  20. Utilization of polymer enclosed intermediate class arresters to improve the performance of modern power systems

    SciTech Connect

    Sakich, J.D.; Lenk, D.W. ); Koepfinger, J.L. )

    1992-07-01

    This paper introduces the first commercially available polymer enclosed intermediate class metal oxide surge arrester. It describes the unique construction of the design, including reduced size, increased flexibility, a collared seal on the polymer housing and an open webbed fiberglass-epoxy module which houses the metal oxide disc elements. Performance advantages are discussed. These include improved short term contamination performance of the insulator-like polymer design when compared to multi-unit porcelain housed designs. Data will show that polymer housed open-webbed fiberglass module construction extends the pressure relief capability beyond that of typical porcelain enclosed designs. The capability of the polymer enclosed design to withstand repeated pressure relief tests, simulating system reclose on a failed arrester, is also discussed. This paper discusses the circumstances at one utility which has considered utilizing polymer enclosed intermediate class arresters to effectively upgrade their system protection capabilities.

  1. Composite Polymer Derived Ceramic System for Oxidizing Environments

    SciTech Connect

    Torrey, Jessica D.; Bordia, Rajendra K.; Henager, Charles H.; Blum, Y.; Shin, Yongsoon; Samuels, William D.

    2006-07-01

    Preceramic polymers and expansion agents are being investigated to process composite ceramic coatings. In this paper, we present results of a systematic approach to selecting the preceramic polymer and expansion agents, and the optimization of the processing parameters to produce composite ceramics. Six commercially available poly(silsesquioxane) polymers and two polysiloxanes were studied. In addition, several metals and intermetallics were considered as potential expansion agents. Based on this study, the most desirable polymer/expansion agent combination and optimal processing parameters have been identified.

  2. Advanced Aqueous Separation Systems for Actinide Partitioning

    SciTech Connect

    Nash, Ken; Martin, Leigh; Lumetta, Gregg

    2015-04-02

    One of the most challenging aspects of advanced processing of used nuclear fuel is the separation of transplutonium actinides from fission product lanthanides. This separation is essential if actinide transmutation options are to be pursued in advanced fuel cycles, as lanthanides compete with actinides for neutrons in both thermal and fast reactors, thus limiting efficiency. The separation is difficult because the chemistry of Am3+ and Cm3+ is nearly identical to that of the trivalent lanthanides (Ln3+). The prior literature teaches that two approaches offer the greatest probability of devising a successful group separation process based on aqueous processes: 1) the application of complexing agents containing ligand donor atoms that are softer than oxygen (N, S, Cl-) or 2) changing the oxidation state of Am to the IV, V, or VI state to increase the essential differences between Am and lanthanide chemistry (an approach utilized in the PUREX process to selectively remove Pu4+ and UO22+ from fission products). The latter approach offers the additional benefit of enabling a separation of Am from Cm, as Cm(III) is resistant to oxidation and so can easily be made to follow the lanthanides. The fundamental limitations of these approaches are that 1) the soft(er) donor atoms that interact more strongly with actinide cations than lanthanides form substantially weaker bonds than oxygen atoms, thus necessitating modification of extraction conditions for adequate phase transfer efficiency, 2) soft donor reagents have been seen to suffer slow phase transfer kinetics and hydro-/radiolytic stability limitations and 3) the upper oxidation states of Am are all moderately strong oxidants, hence of only transient stability in media representative of conventional aqueous separations systems. There are examples in the literature of both approaches having been described. However, it is not clear at present that any extant process is sufficiently robust for application at the scale

  3. Electronic excited states and relaxation dynamics in polymer heterojunction systems

    NASA Astrophysics Data System (ADS)

    Ramon, John Glenn Santos

    The potential for using conducting polymers as the active material in optoelectronic devices has come to fruition in the past few years. Understanding the fundamental photophysics behind their operations points to the significant role played by the polymer interface in their performance. Current device architectures involve the use of bulk heterojunctions which intimately blend the donor and acceptor polymers to significantly increase not only their interfacial surface area but also the probability of exciton formation within the vicinity of the interface. In this dissertation, we detail the role played by the interface on the behavior and performance of bulk heterojunction systems. First, we explore the relation between the exciton binding energy to the band offset in determining device characteristics. As a general rule, when the exciton binding energy is greater than the band offset, the exciton remains the lowest energy excited state leading to efficient light-emitting properties. On the other hand, if the offset is greater than the binding energy, charge separation becomes favorable leading to better photovoltaic behavior. Here, we use a Wannier function, configuration interaction based approach to examine the essential excited states and predict the vibronic absorption and emission spectra of the PPV/BBL, TFB/F8BT and PFB/F8BT heterojunctions. Our results underscore the role of vibrational relaxation in the formation of charge-transfer states following photoexcitation. In addition, we look at the relaxation dynamics that occur upon photoexcitation. For this, we adopt the Marcus-Hush semiclassical method to account for lattice reorganization in the calculation of the interconversion rates in TFB/F8BT and PFB/F8BT. We find that, while a tightly bound charge-transfer state (exciplex) remains the lowest excited state, a regeneration pathway to the optically active lowest excitonic state in TFB/F8BT is possible via thermal repopulation from the exciplex. Finally

  4. Threaded molecular wires as building blocks for advanced polymer blends: WPLEDs, ultra-broadband optical amplifiers, multi color lasers

    NASA Astrophysics Data System (ADS)

    Brovelli, Sergio; Mroz, Marta; Sforazzini, Giuseppe; Virgili, Tersilla; Meinardi, Franco; Paleari, Alberto; Anderson, Harry L.; Lanzani, Guglielmo; Cacialli, Franco

    2011-03-01

    The ability to produce semiconducting polymer blends with white emission spectra, large emission cross sections and broad optical gain is critical to their application in white PLEDs, lasers and broadband amplifiers. Cyclodextrin-encapsulation is an effective means of suppressing detrimental intermolecular interactions, and energy transfer (ET) channels in polymer blends, thus enabling fabrication of white-PLEDs. We show that all such properties combine into a high impact photonic application: ultra-broad optical gain and two-color lasing in a binary polyrotaxane blend. We study the ultrafast photophysics of a blend of a conventional and an encapsulated polyfluorene. The morphology is investigated by microRaman imaging, AFM, and fluorescence lifetime microscopy. We ascribe the ultra-broad optical gain (>850 meV), and the simultaneous ASE for both constituents, to the dual effect of reduced polaron formation and suppressed ET. Our results demonstrate that polyrotaxanes could realistically represent the building blocks for advanced polymer blends with highly controlled optical properties, for applications in solid state lightning, lasers and photovoltaic technologies.

  5. Review on recent and advanced applications of monoliths and related porous polymer gels in micro-fluidic devices.

    PubMed

    Vázquez, Mercedes; Paull, Brett

    2010-06-01

    This review critically summarises recent novel and advanced achievements in the application of monolithic materials and related porous polymer gels in micro-fluidic devices appearing within the literature over the period of the last 5 years (2005-2010). The range of monolithic materials has developed rapidly over the past decade, with a diverse and highly versatile class of materials now available, with each exhibiting distinct porosities, pore sizes, and a wide variety of surface functionalities. A major advantage of these materials is their ease of preparation in micro-fluidic channels by in situ polymerisation, leading to monolithic materials being increasingly utilised for a larger variety of purposes in micro-fluidic platforms. Applications of porous polymer monoliths, silica-based monoliths and related homogeneous porous polymer gels in the preparation of separation columns, ion-permeable membranes, preconcentrators, extractors, electrospray emitters, micro-valves, electrokinetic pumps, micro-reactors and micro-mixers in micro-fluidic devices are discussed herein. Procedures used in the preparation of monolithic materials in micro-channels, as well as some practical aspects of the micro-fluidic chip fabrication are addressed. Recent analytical/bioanalytical and catalytic applications of the final micro-fluidic devices incorporating monolithic materials are also reviewed. PMID:20493286

  6. Advanced coal-fueled gas turbine systems

    SciTech Connect

    Not Available

    1992-09-01

    Westinghouse's Advanced Coal-Fueled Gas Turbine System Program (DE-AC2l-86MC23167) was originally split into two major phases - a Basic Program and an Option. The Basic Program also contained two phases. The development of a 6 atm, 7 lb/s, 12 MMBtu/hr slagging combustor with an extended period of testing of the subscale combustor, was the first part of the Basic Program. In the second phase of the Basic Program, the combustor was to be operated over a 3-month period with a stationary cascade to study the effect of deposition, erosion and corrosion on combustion turbine components. The testing of the concept, in subscale, has demonstrated its ability to handle high- and low-sulfur bituminous coals, and low-sulfur subbituminous coal. Feeding the fuel in the form of PC has proven to be superior to CWM type feed. The program objectives relative to combustion efficiency, combustor exit temperature, NO[sub x] emissions, carbon burnout, and slag rejection have been met. Objectives for alkali, particulate, and SO[sub x] levels leaving the combustor were not met by the conclusion of testing at Textron. It is planned to continue this testing, to achieve all desired emission levels, as part of the W/NSP program to commercialize the slagging combustor technology.

  7. Vacuum system for Advanced Test Accelerator

    SciTech Connect

    Denhoy, B.S.

    1981-09-03

    The Advanced Test Accelerator (ATA) is a pulsed linear electron beam accelerator designed to study charged particle beam propagation. ATA is designed to produce a 10,000 amp 50 MeV, 70 ns electron beam. The electron beam acceleration is accomplished in ferrite loaded cells. Each cell is capable of maintaining a 70 ns 250 kV voltage pulse across a 1 inch gap. The electron beam is contained in a 5 inch diameter, 300 foot long tube. Cryopumps turbomolecular pumps, and mechanical pumps are used to maintain a base pressure of 2 x 10/sup -6/ torr in the beam tube. The accelerator will be installed in an underground tunnel. Due to the radiation environment in the tunnel, the controlling and monitoring of the vacuum equipment, pressures and temperatures will be done from the control room through a computer interface. This paper describes the vacuum system design, the type of vacuum pumps specified, the reasons behind the selection of the pumps and the techniques used for computer interfacing.

  8. Advances in systemic treatment for nasopharyngeal carcinoma.

    PubMed

    Tan, Wan-Ling; Tan, Eng-Huat; Lim, Darren Wan-Teck; Ng, Quan-Sing; Tan, Daniel Shao-Weng; Jain, Amit; Ang, Mei-Kim

    2016-04-01

    Nasopharyngeal carcinoma (NPC) is a unique disease endemic in Asia. It is etiologically linked to the Epstein-Barr virus and is both radio- and chemo-sensitive. While radiotherapy (RT) remains the primary treatment modality with high cure rates for early stage disease, systemic treatment forms an important integral component in the treatment of NPC, both in the non-metastatic as well as palliative setting. Presently, standard therapy in locally advanced NPC comprises conventional cytotoxic chemotherapy administered concurrently during RT. The role of induction chemotherapy and adjuvant chemotherapy remain to be well-defined. Further research strategies in non-metastatic disease will require better identification of patients with high risk disease, and determining the optimal sequence and combination of chemotherapeutic regimens. In metastatic disease, whilst chemotherapy remains the mainstay of care, resistance inevitably develops. Development of molecularly targeted therapies has not yielded much success to date, and further research has been focused on development of EBV-targeted strategies such as vaccination or administration of cytotoxic T-cells directed towards EBV, as well as evaluation of immune checkpoint inhibition approaches. PMID:27121881

  9. Advanced materials for thermal protection system

    NASA Astrophysics Data System (ADS)

    Heng, Sangvavann; Sherman, Andrew J.

    1996-03-01

    Reticulated open-cell ceramic foams (both vitreous carbon and silicon carbide) and ceramic composites (SiC-based, both monolithic and fiber-reinforced) were evaluated as candidate materials for use in a heat shield sandwich panel design as an advanced thermal protection system (TPS) for unmanned single-use hypersonic reentry vehicles. These materials were fabricated by chemical vapor deposition/infiltration (CVD/CVI) and evaluated extensively for their mechanical, thermal, and erosion/ablation performance. In the TPS, the ceramic foams were used as a structural core providing thermal insulation and mechanical load distribution, while the ceramic composites were used as facesheets providing resistance to aerodynamic, shear, and erosive forces. Tensile, compressive, and shear strength, elastic and shear modulus, fracture toughness, Poisson's ratio, and thermal conductivity were measured for the ceramic foams, while arcjet testing was conducted on the ceramic composites at heat flux levels up to 5.90 MW/m2 (520 Btu/ft2ṡsec). Two prototype test articles were fabricated and subjected to arcjet testing at heat flux levels of 1.70-3.40 MW/m2 (150-300 Btu/ft2ṡsec) under simulated reentry trajectories.

  10. RASSOR - Regolith Advanced Surface Systems Operations Robot

    NASA Technical Reports Server (NTRS)

    Gill, Tracy R.; Mueller, Rob

    2015-01-01

    The Regolith Advanced Surface Systems Operations Robot (RASSOR) is a lightweight excavator for mining in reduced gravity. RASSOR addresses the need for a lightweight (<100 kg) robot that is able to overcome excavation reaction forces while operating in reduced gravity environments such as the moon or Mars. A nominal mission would send RASSOR to the moon to operate for five years delivering regolith feedstock to a separate chemical plant, which extracts oxygen from the regolith using H2 reduction methods. RASSOR would make 35 trips of 20 kg loads every 24 hours. With four RASSORs operating at one time, the mission would achieve 10 tonnes of oxygen per year (8 t for rocket propellant and 2 t for life support). Accessing craters in space environments may be extremely hard and harsh due to volatile resources - survival is challenging. New technologies and methods are required. RASSOR is a product of KSC Swamp Works which establishes rapid, innovative and cost effective exploration mission solutions by leveraging partnerships across NASA, industry and academia.

  11. Mass and Charge Transport in the Polymer-Ionic-Liquid System PEO-EMImI: From Ionic-Liquid-in-Polymer to Polymer-in-Ionic-Liquid Electrolytes.

    PubMed

    Kösters, Johannes; Schönhoff, Monika; Stolwijk, Nicolaas A

    2015-04-30

    Conventional polymer electrolytes based on inorganic salts are commonly characterized and utilized over a small salt-poor composition range because of phase transitions accompanied by loss of ion conductivity at high salt concentrations. By contrast, well-chosen polymer-ionic-liquid (IL) systems offer the possibility to vary the IL content from the IL-in-polymer to the polymer-in-IL domain. We have investigated the temperature-dependent ionic conductivity in PEOyEMImI systems consisting of poly(ethylene oxide) complexed with 1-ethyl-3-methylimidazolium iodide for y = EO/IL ratios ranging from 0.6 to 60 and compared diffusivity data with that arising from (1)H pulsed-field-gradient nuclear magnetic resonance for EMIm and (125)I radiotracer diffusion for iodine. Surprisingly, the diffusivity of cations and anions vary at most by 50% at fixed temperatures over the entire composition range. The much larger changes in the charge diffusivity Dσ relate to ion pairing exhibiting a minimum near the intermediate composition y = 10. Altogether, the results are relevant to application in dye-sensitized solar cells and show that a high ion density is crucial to enhance the iodine transport capacity. PMID:25848686

  12. The Effect of 3rd Component on the Melt Rheology of Polymer Blend System

    NASA Astrophysics Data System (ADS)

    Koyama, Kiyohito; Uematsu, Hideyuki; Sugimoto, Masataka; Taniguchi, Takashi; Inada, Teiichi; Iwakura, Tetsuro

    2008-07-01

    Uniaxial elongational flow behavior of polymer blend system containing three components (acrylic polymer, epoxy resin and SiO2) was investigated. The strain softening was observed at 80 °C and the strain hardening was observed at 60 °C for the same sample. We found that these non-linear properties in uniaxial elongational flow behavior can be varied by temperature change for polymer blend containing three components.

  13. Advanced Systems for Monitoring Underwater Sounds

    NASA Technical Reports Server (NTRS)

    Lane, Michael; Van Meter, Steven; Gilmore, Richard Grant; Sommer, Keith

    2007-01-01

    The term "Passive Acoustic Monitoring System" (PAMS) describes a developmental sensing-and-data-acquisition system for recording underwater sounds. The sounds (more precisely, digitized and preprocessed versions from acoustic transducers) are subsequently analyzed by a combination of data processing and interpretation to identify and/or, in some cases, to locate the sources of those sounds. PAMS was originally designed to locate the sources such as fish of species that one knows or seeks to identify. The PAMS unit could also be used to locate other sources, for example, marine life, human divers, and/or vessels. The underlying principles of passive acoustic sensing and analyzing acoustic-signal data in conjunction with temperature and salinity data are not new and not unique to PAMS. Part of the uniqueness of the PAMS design is that it is the first deep-sea instrumentation design to provide a capability for studying soniferous marine animals (especially fish) over the wide depth range described below. The uniqueness of PAMS also lies partly in a synergistic combination of advanced sensing, packaging, and data-processing design features with features adapted from proven marine instrumentation systems. This combination affords a versatility that enables adaptation to a variety of undersea missions using a variety of sensors. The interpretation of acoustic data can include visual inspection of power-spectrum plots for identification of spectral signatures of known biological species or artificial sources. Alternatively or in addition, data analysis could include determination of relative times of arrival of signals at different acoustic sensors arrayed at known locations. From these times of arrival, locations of acoustic sources (and errors in those locations) can be estimated. Estimates of relative locations of sources and sensors can be refined through analysis of the attenuation of sound in the intervening water in combination with water-temperature and salinity

  14. Dynamics of various polymer-graphene interfacial systems through atomistic molecular dynamics simulations.

    PubMed

    Rissanou, Anastassia N; Harmandaris, Vagelis

    2014-04-28

    The current work refers to a simulation study on hybrid polymer-graphene interfacial systems. We explore the effect of graphene on the mobility of polymers, by studying three well known and widely used polymers, polyethylene (PE), polystyrene (PS) and poly(methyl-methacrylate) (PMMA). Qualitative and quantitative differences in the dynamical properties of the polymer chains in particular at the polymer-graphene interface are detected. Results concerning both the segmental and the terminal dynamics render PE much faster than the other two polymers; PS follows, while PMMA is the slowest one. Clear spatial dynamic heterogeneity has been observed for all model systems, with different dynamical behavior of the adsorbed polymer segments. The segmental relaxation time of the polymer (τseg) as a function of the distance from graphene shows an abrupt decrease beyond the first adsorption layer for PE, as a result of its well-ordered layered structure close to graphene, though a more gradual decay is observed for PS and PMMA. The distribution of the relaxation times of adsorbed segments was also found to be broader than those of the bulk ones for all three polymer-graphene systems. PMID:24667937

  15. Design and test status for life support applications of SPE oxygen generation systems. [Solid Polymer Electrolyte

    NASA Technical Reports Server (NTRS)

    Titterington, W. A.; Erickson, A. C.

    1975-01-01

    An advanced six-man rated oxygen generation system has been fabricated and tested as part of a NASA/JSC technology development program for a long lived, manned spacecraft life support system. Details of the design and tests results are presented. The system is based on the Solid Polymer Electrolyte (SPE) water electrolysis technology and its nominal operating conditions are 2760 kN/sq m (400 psia) and 355 K (180 F) with an electrolysis module current density capability up to 350 mA/sq cm (326 ASF). The system is centered on a 13-cell SPE water electrolysis module having a single cell active area of 214 sq cm (33 sq in) and it incorporates instrumentation and controls for single pushbutton automatic startup/shutdown, component fault detection and isolation, and self-contained sensors and controls for automatic safe emergency shutdown. The system has been tested in both the orbital cyclic and continuous mode of operation. Various parametric tests have been completed to define the system capability for potential application in spacecraft environmental systems.

  16. Advanced analysis of polymer emulsions: Particle size and particle size distribution by field-flow fractionation and dynamic light scattering.

    PubMed

    Makan, Ashwell C; Spallek, Markus J; du Toit, Madeleine; Klein, Thorsten; Pasch, Harald

    2016-04-15

    Field flow fractionation (FFF) is an advanced fractionation technique for the analyses of very sensitive particles. In this study, different FFF techniques were used for the fractionation and analysis of polymer emulsions/latexes. As model systems, a pure acrylic emulsion and emulsions containing titanium dioxide were prepared and analyzed. An acrylic emulsion polymerization was conducted, continuously sampled from the reactor and subsequently analyzed to determine the particle size, radius of gyration in specific, of the latex particles throughout the polymerization reaction. Asymmetrical flow field-flow fractionation (AF4) and sedimentation field-flow fractionation (SdFFF), coupled to a multidetector system, multi-angle laser light scattering (MALLS), ultraviolet (UV) and refractive index (RI), respectively, were used to investigate the evolution of particle sizes and particle size distributions (PSDs) as the polymerization progressed. The obtained particle sizes were compared against batch-mode dynamic light scattering (DLS). Results indicated differences between AF4 and DLS results due to DLS taking hydration layers into account, whereas both AF4 and SdFFF were coupled to MALLS detection, hence not taking the hydration layer into account for size determination. SdFFF has additional separation capabilities with a much higher resolution compared to AF4. The calculated radii values were 5 nm larger for SdFFF measurements for each analyzed sample against the corresponding AF4 values. Additionally a low particle size shoulder was observed for SdFFF indicating bimodality in the reactor very early during the polymerization reaction. Furthermore, different emulsions were mixed with inorganic species used as additives in cosmetics and coatings such as TiO2. These complex mixtures of species were analyzed to investigate the retention and particle interaction behavior under different AF4 experimental conditions, such as the mobile phase. The AF4 system was coupled online

  17. Compact hydrogen production systems for solid polymer fuel cells

    NASA Astrophysics Data System (ADS)

    Ledjeff-Hey, K.; Formanski, V.; Kalk, Th.; Roes, J.

    Generally there are several ways to produce hydrogen gas from carbonaceous fuels like natural gas, oil or alcohols. Most of these processes are designed for large-scale industrial production and are not suitable for a compact hydrogen production system (CHYPS) in the power range of 1 kW. In order to supply solid polymer fuel cells (SPFC) with hydrogen, a compact fuel processor is required for mobile applications. The produced hydrogen-rich gas has to have a low level of harmful impurities; in particular the carbon monoxide content has to be lower than 20 ppmv. Integrating the reaction step, the gas purification and the heat supply leads to small-scale hydrogen production systems. The steam reforming of methanol is feasible at copper catalysts in a low temperature range of 200-350°C. The combination of a small-scale methanol reformer and a metal membrane as purification step forms a compact system producing high-purity hydrogen. The generation of a SPFC hydrogen fuel gas can also be performed by thermal or catalytic cracking of liquid hydrocarbons such as propane. At a temperature of 900°C the decomposition of propane into carbon and hydrogen takes place. A fuel processor based on this simple concept produces a gas stream with a hydrogen content of more than 90 vol.% and without CO and CO2.

  18. Advances in Global Flood Forecasting Systems

    NASA Astrophysics Data System (ADS)

    Thielen-del Pozo, J.; Pappenberger, F.; Burek, P.; Alfieri, L.; Kreminski, B.; Muraro, D.

    2012-12-01

    -meteorological processes are not fully captured and calibration is necessary. Critical thresholds are computed from long-term simulations where the coupled HTESSEL/LISFLOOD model is driven with ERA-Interim data for a period of 21 years.From the longterm runs return periods are estimated against which each flood forecasts are compared. Results are displayed as maps and time series on a web-interface providing global overviews as well as local quantitative information. Major floods such as the ones in South East Asia in September-October 2010 in Thailand, Cambodia and Vietnam were well captured by the system: for the lower Mekong River, probabilistic forecasts from the global simulations on the 18th September 2011 showed a probability higher than 40% of exceeding the high alert level from 2nd-4th October, hence 14 days in advance. Collaborations exist between the EU and Brazil to further the system for Brazilian rivers. Next steps include further research and development, rigorous testing and adaptations. calibration of the system with available data, and work on selected case studies for quantitative improvements.

  19. ADVANCED POWER SYSTEMS ASH BEHAVIOR IN POWER SYSTEMS

    SciTech Connect

    ZYGARLICKE, CHRISTOPHER J; MCCOLLOR, DONALD P; KAY, JOHN P; SWANSON, MICHAEL L

    1998-09-01

    The overall goal of this initiative is to develop fundamental knowledge of ash behavior in power systems for the purpose of increasing power production efficiency, reducing operation and maintenance costs, and reducing greenhouse gas emissions into the atmosphere. The specific objectives of this initiative focus primarily on ash behavior related to advanced power systems and include the following: Determine the current status of the fundamental ash interactions and deposition formation mechanisms as already reported through previous or ongoing projects at the EERC or in the literature. Determine sintering mechanisms for temperatures and particle compositions that are less well known and remain for the most part undetermined. Identify the relationship between the temperature of critical viscosity (Tcv ) as measured in a viscometer and the crystallization occurring in the melt. Perform a literature search on the use of heated-stage microscopy (HSM) for examining in situ ash-sintering phenomena and then validate the use of HSM in the determination of viscosity in spherical ash particles. Ascertain the formation and stability of specific mineral or amorphous phases in deposits typical of advanced power systems. Evaluate corrosion for alloys being used in supercritical combustion systems.

  20. Norbornylene-based polymer systems for dielectric applications

    SciTech Connect

    Dirk, Shawn M.; Wheeler, David R.

    2012-07-17

    A capacitor having at least one electrode pair being separated by a dielectric component, with the dielectric component being made of a polymer such as a norbornylene-containing polymer with a dielectric constant greater than 3 and a dissipation factor less than 0.1 where the capacitor has an operating temperature greater than 100.degree. C. and less than 170.degree. C.

  1. Responsive Biomaterials: Advances in Materials Based on Shape-Memory Polymers.

    PubMed

    Hardy, John G; Palma, Matteo; Wind, Shalom J; Biggs, Manus J

    2016-07-01

    Shape-memory polymers (SMPs) are morphologically responsive materials with potential for a variety of biomedical applications, particularly as devices for minimally invasive surgery and the delivery of therapeutics and cells for tissue engineering. A brief introduction to SMPs is followed by a discussion of the current progress toward the development of SMP-based biomaterials for clinically relevant biomedical applications. PMID:27120512

  2. Preparation of metallic cation conducting polymers based on sterically hindered phenols containing polymeric systems

    DOEpatents

    Skotheim, T.A.; Okamoto, Yoshiyuki; Lee, H.S.

    1989-11-21

    The present invention relates to ion-conducting solvent-free polymeric systems characterized as being cationic single ion conductors. The solvent-free polymer electrolytes comprise a flexible polymer backbone to which is attached a metal salt, such as a lithium, sodium or potassium salt, of a sterically hindered phenol. The solid polymer electrolyte may be prepared either by (1) attaching the hindered phenol directly to a flexible polymeric backbone, followed by neutralization of the phenolic OH's or (2) reacting the hindered phenol with a polymer precursor which is then polymerized to form a flexible polymer having phenolic OH's which are subsequently neutralized. Preferably the hindered phenol-modified polymeric backbone contains a polyether segment. The ionic conductivity of these solvent-free polymer electrolytes has been measured to be in the range of 10[sup [minus]4] to 10[sup [minus]7] S cm[sup [minus]1] at room temperature.

  3. Preparation of metallic cation conducting polymers based on sterically hindered phenols containing polymeric systems

    DOEpatents

    Skotheim, Terje A.; Okamoto, Yoshiyuki; Lee, Hung S.

    1989-01-01

    The present invention relates to ion-conducting solvent-free polymeric systems characterized as being cationic single ion conductors. The solvent-free polymer electrolytes comprise a flexible polymer backbone to which is attached a metal salt, such as a lithium, sodium or potassium salt, of a sterically hindered phenol. The solid polymer electrolyte may be prepared either by (1) attaching the hindered phenol directly to a flexible polymeric backbone, followed by neutralization of the phenolic OH's or (2) reacting the hindered phenol with a polymer precursor which is then polymerized to form a flexible polymer having phenolic OH's which are subsequently neutralized. Preferably the hindered phenol-modified polymeric backbone contains a polyether segment. The ionic conductivity of these solvent-free polymer electrolytes has been measured to be in the range of 10.sup.-4 to 10.sup.-7 S cm.sup.-1 at room temperature.

  4. Atmospheric fluidized bed combustion advanced concept system

    SciTech Connect

    Not Available

    1992-05-01

    DONLEE Technologies Inc. is developing with support of the US Department of Energy an advanced circulating fluidized bed technology known as the Vortex{trademark} Fluidized Bed Combustor (VFBC). The unique feature of the VFBC is the injection of a significant portion of the combustion air into the cyclone. Since as much as one-half of the total combustion air is injected into the cyclone, the cross-sectional area of the circulating fluidized bed is considerably smaller than typical circulating fluidized beds. The technology is being developed for two applications: Industrial-scale boilers ranging from 20,000 to 100,000 pounds per hour steam generating capacity; and two-stage combustion in which a substoichiometric Vortex Fluidized Bed Combustor (2VFBC) or precombustor is used to generate a combustible gas for use primarily in boiler retrofit applications. This Level II analysis of these two applications indicates that both have merit. An industrial-scale VFBC boiler (60,000 lb/hr of steam) is projected to be economically attractive with coal prices as high as $40 per ton and gas prices between $4 and $5 per thousand cubic feet. The payback time is between 3 and 4 years. The 2VFBC system was evaluated at three capacities of application: 20,000; 60,000 and 100,000 lb/hr of steam. The payback times for these three capacities are 4.5, 2.1 and 1.55 years, respectively. The 2VFBC has potential applications for retrofit of existing pulverized coal-fired boilers or as a new large (utility) boiler. Pressurized operation of the 2VFBC has considerable potential for combined cycle power generation applications. Experimental development of both applications is presented here to demonstrate the potential of these two technologies.

  5. Advanced Command Destruct System (ACDS) Enhanced Flight Termination System (EFTS)

    NASA Technical Reports Server (NTRS)

    Tow, David

    2009-01-01

    NASA Dryden started working towards a single vehicle enhanced flight termination system (EFTS) in January 2008. NASA and AFFTC combined their efforts to work towards final operating capability for multiple vehicle and multiple missions simultaneously, to be completed by the end of 2011. Initially, the system was developed to support one vehicle and one frequency per mission for unmanned aerial vehicles (UAVs) at NASA Dryden. By May 2008 95% of design and hardware builds were completed, however, NASA Dryden's change of software safety scope and requirements caused delays after May 2008. This presentation reviews the initial and final operating capabilities for the Advanced Command Destruct System (ACDS), including command controller and configuration software development. A requirements summary is also provided.

  6. Advanced turbine systems study system scoping and feasibility study

    SciTech Connect

    Not Available

    1993-04-01

    United Technologies Research Center, Pratt Whitney Commercial Engine Business, And Pratt Whitney Government Engine and Space Propulsion has performed a preliminary analysis of an Advanced Turbine System (ATS) under Contract DE-AC21-92MC29247 with the Morgantown Energy Technology Center. The natural gas-fired reference system identified by the UTC team is the Humid Air Turbine (HAT) Cycle in which the gas turbine exhaust heat and heat rejected from the intercooler is used in a saturator to humidify the high pressure compressor discharge air. This results in a significant increase in flow through the turbine at no increase in compressor power. Using technology based on the PW FT4000, the industrial engine derivative of the PW4000, currently under development by PW, the system would have an output of approximately 209 MW and an efficiency of 55.3%. Through use of advanced cooling and materials technologies similar to those currently in the newest generation military aircraft engines, a growth version of this engine could attain approximately 295 MW output at an efficiency of 61.5%. There is the potential for even higher performance in the future as technology from aerospace R D programs is adapted to aero-derivative industrial engines.

  7. Characterization studies of plasticized PEO-PMMA nano-composite polymer electrolyte system

    NASA Astrophysics Data System (ADS)

    Sharma, Poonam; Kanchan, D. K.; Gondaliya, Nirali; Pant, Meenakshi; Jayswal, Manish S.; Joge, Prajakta

    2012-06-01

    Present study reports the characterization studies on silver based PEO-PMMA-PEG nano composite polymer electrolyte system, prepared by solution cast technique. The complexation among various constituents of polymer samples was carried by XRD and FTIR analysis. Thermal analysis of the samples was carried out by DSC study.

  8. Effects of carbon nanoparticles on properties of thermoset polymer systems

    NASA Astrophysics Data System (ADS)

    Movva, Siva Subramanyam

    Polymer nanocomposites are novel materials in which at least one of the dimensions of the reinforcing material is on the order of 100 nm or less. While thermoplastic nanocomposites have been studied very widely, there are fewer studies concerning the effect of nanoparticles on thermoset systems. Low temperature cure thermoset systems are very important for many important applications. In this study, the processing, mechanical and thermal properties and reaction kinetics of carbon nanofiber (CNF) and/or carbon nanotubes (CNT) reinforced low temperature vinyl ester and epoxy nanocomposites were studied. In the first part, the processing challenge of incorporating CNFs into conventional fiber reinforced composites made by Vacuum infusion resin transfer molding (VARTM) was addressed by a new technique. The CNFs are pre-bound on the long fiber mats, instead of mixing them in the polymer resin, thereby eliminating several processing drawbacks. The resulting hybrid nanocomposites showed significant improvements in tensile, flexural and thermal properties. The effect of CNFs on the mold filling in VARTM was also studied and shown to follow the Darcy's law. In the second part, the effect of CNFs on the low temperature cure kinetics of vinyl ester and epoxy resins is studied using a thermal analysis technique, namely Differential scanning calorimetry (DSC). The effect of CNFs on the free radical polymerization of vinyl esters was found to be very complex as the CNFs interact with the various curing ingredients in the formulation. Specifically, the interaction effects of CNFs and the inhibitor were studied and a reaction mechanism was proposed to explain the observed phenomenon. The effect of surface modification of the carbon nanoparticles on the cure kinetics of wind-blade epoxy was studied. The surface functionalization reduced the activation energy of the epoxy reaction and was found to have an acceleration effect on the cure kinetics of epoxy resin at room temperature

  9. Advanced Control and Power System (ACAPS) Technology Program

    NASA Technical Reports Server (NTRS)

    Keckler, C. R.; Groom, N. J.

    1983-01-01

    The advanced control and power system (ACAPS) program is to establish the technology necessary to satisfy space station and related large space structures requirements for efficient, reliable, and cost effective energy storage and attitude control. Technology advances in the area of integrated flywheel systems capable of performing the dual functions of energy storage and attitude control are outlined.

  10. Advanced PID type fuzzy logic power system stabilizer

    SciTech Connect

    Hiyama, Takashi; Kugimiya, Masahiko; Satoh, Hironori . Dept. of Electrical Engineering and Computer Science)

    1994-09-01

    An advanced fuzzy logic control scheme has been proposed for a micro-computer based power system stabilizer to enhance the overall stability of power systems. The proposed control scheme utilizes the PID information of the generator speed. The input signal to the stabilizer is the real power output of a study unit. Simulations show the effectiveness of the advanced fuzzy logic control scheme.

  11. Polymer-Dopant-Systems: Tailoring of Optical and Thermomechanical Properties

    NASA Astrophysics Data System (ADS)

    Hanemann, Thomas; Honnef, Kirsten

    2010-06-01

    For modern application in microoptics the refractive index of polymers can be adjusted in a certain range by the addition of electron-rich organic dopants. As an unwanted side-effect a pronounced plasticizing occurs. In this work the addition of a crosslinker (divinylbenzene) to the unsaturated polyester matrix, doped with phenanthrene for refractive index adjustment, allows for a successful suppression of the plasticizing effect measured after polymerization. Even at high phenanthrene concentrations the glass transition temperature of the initial polymer could be almost retained. An increase of the polymers refractive index from 1.5684 up to a value of 1.6425 could be achieved.

  12. Rotorcraft digital advanced avionics system (RODAAS) functional description

    NASA Technical Reports Server (NTRS)

    Peterson, E. M.; Bailey, J.; Mcmanus, T. J.

    1985-01-01

    A functional design of a rotorcraft digital advanced avionics system (RODAAS) to transfer the technology developed for general aviation in the Demonstration Advanced Avionics System (DAAS) program to rotorcraft operation was undertaken. The objective was to develop an integrated avionics system design that enhances rotorcraft single pilot IFR operations without increasing the required pilot training/experience by exploiting advanced technology in computers, busing, displays and integrated systems design. A key element of the avionics system is the functionally distributed architecture that has the potential for high reliability with low weight, power and cost. A functional description of the RODAAS hardware and software functions is presented.

  13. Innovative technology summary report: advanced worker protection system

    SciTech Connect

    1996-04-01

    The Advanced Worker Protection System (AWPS) is a liquid-air-based, self-contained breathing and cooling system with a duration of 2 hrs. AWPS employs a patented system developed by Oceaneering Space Systems (OSS), which was supported by the Department of Energy's (DOE's) Morgantown Energy Technology Center through a cost sharing research and development contract. The heart of the system is the life-support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack is combined with advanced protective garments, an advanced liquid cooling garment (LCG), a respirator, and communications and support equipment.

  14. Development and characteristics of polymer monoliths for advanced LC bioscreening applications: A review.

    PubMed

    Acquah, Caleb; Moy, Charles K S; Danquah, Michael K; Ongkudon, Clarence M

    2016-03-15

    Biomedical research advances over the past two decades in bioseparation science and engineering have led to the development of new adsorbent systems called monoliths, mostly as stationary supports for liquid chromatography (LC) applications. They are acknowledged to offer better mass transfer hydrodynamics than their particulate counterparts. Also, their architectural and morphological traits can be tailored in situ to meet the hydrodynamic size of molecules which include proteins, pDNA, cells and viral targets. This has enabled their development for a plethora of enhanced bioscreening applications including biosensing, biomolecular purification, concentration and separation, achieved through the introduction of specific functional moieties or ligands (such as triethylamine, N,N-dimethyl-N-dodecylamine, antibodies, enzymes and aptamers) into the molecular architecture of monoliths. Notwithstanding, the application of monoliths presents major material and bioprocess challenges. The relationship between in-process polymerisation characteristics and the physicochemical properties of monolith is critical to optimise chromatographic performance. There is also a need to develop theoretical models for non-invasive analyses and predictions. This review article therefore discusses in-process analytical conditions, functionalisation chemistries and ligands relevant to establish the characteristics of monoliths in order to facilitate a wide range of enhanced bioscreening applications. It gives emphasis to the development of functional polymethacrylate monoliths for microfluidic and preparative scale bio-applications. PMID:26919447

  15. F/A-18 FAST Offers Advanced System Test Capability

    NASA Video Gallery

    NASA's Dryden Flight Research Center has modified an F/A-18A Hornet aircraft with additional research flight control computer systems for use as a Full-scale Advanced Systems Test Bed. Previously f...

  16. Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging.

    PubMed

    Crick, Colin R; Noimark, Sacha; Peveler, William J; Bear, Joseph C; Ivanov, Aleksandar P; Edel, Joshua B; Parkin, Ivan P

    2016-01-01

    The fabrication of polymer-nanoparticle composites is extremely important in the development of many functional materials. Identifying the precise composition of these materials is essential, especially in the design of surface catalysts, where the surface concentration of the active component determines the activity of the material. Antimicrobial materials which utilize nanoparticles are a particular focus of this technology. Recently swell encapsulation has emerged as a technique for inserting antimicrobial nanoparticles into a host polymer matrix. Swell encapsulation provides the advantage of localizing the incorporation to the external surfaces of materials, which act as the active sites of these materials. However, quantification of this nanoparticle uptake is challenging. Previous studies explore the link between antimicrobial activity and surface concentration of the active component, but this is not directly visualized. Here we show a reliable method to monitor the incorporation of nanoparticles into a polymer host matrix via swell encapsulation. We show that the surface concentration of CdSe/ZnS nanoparticles can be accurately visualized through cross-sectional fluorescence imaging. Using this method, we can quantify the uptake of nanoparticles via swell encapsulation and measure the surface concentration of encapsulated particles, which is key in optimizing the activity of functional materials. PMID:27500449

  17. Advance prototype silver ion water bactericide system

    NASA Technical Reports Server (NTRS)

    Jasionowski, W. J.; Allen, E. T.

    1974-01-01

    An advance prototype unit was designed and fabricated to treat anticipated fuel cell water. The unit is a single canister that contains a membrane-type prefilter and a silver bromide contacting bed. A seven day baseline simulated mission test was performed; the performance was satisfactory and the effluent water was within all specifications for potability. After random vibrations another seven day simulated mission test was performed, and results indicate that simulated launch vibrations have no effects on the design and performance of the advanced prototype. Bench tests and accelerated breadboard tests were conducted to define the characteristics of an upgraded model of the advance prototype unit which would have 30 days of operating capability. A preliminary design of a silver ion generator for the shuttle orbiter was also prepared.

  18. Systemic Therapy for Advanced Soft Tissue Sarcoma.

    PubMed

    Sheng, Jennifer Y; Movva, Sujana

    2016-10-01

    Soft tissue sarcomas are rare tumors that present with distant metastasis in up to 10% of patients. Survival has improved significantly because of advancements in histologic classification and improved management approaches. Older agents such as doxorubicin, ifosfamide, gemcitabine, and paclitaxel continue to demonstrate objective response rates from 18% to 25%. Newer agents such as trabectedin, eribulin, aldoxorubicin, and olaratumab have demonstrated improvements in progression-free survival, overall survival, or toxicity profiles. Future studies on treatment of advanced soft tissue sarcoma will continue to concentrate on reducing toxicity, personalization of therapy, and targeting novel pathways. PMID:27542647

  19. Advanced technology for future space propulsion systems

    NASA Technical Reports Server (NTRS)

    Diehl, Larry A.

    1989-01-01

    The NASA Project Pathfinder contains programs to provide technologies for future transfer vehicles including those powered by both advanced chemical and electric propulsion rockets. This paper discusses the Chemical Transfer Propulsion and Cargo Vehicle Propulsion elements of Pathfinder. The program requirements and goals for both elements are discussed, and technical activities which are planned or underway are summarized. Recent progress in programs which support or proceed the Pathfinder activities is detailed. In particular, the NASA Program for Advanced Orbital Transfer Vehicle Propulsion, which acted as the precursor for the Chemical Transfer Propulsion element of Pathfinder is summarized.

  20. Contribution of polymers to classical primary insulation of distribution system

    SciTech Connect

    Shwehdi, M.H.; Al-Rawi, A.

    1996-12-31

    Insulation composites used on present distribution lines frequently consist of several types of materials such as wood, porcelain, polymers and fiberglass reinforced plastics (FRP) connected in series. A study included the laboratory determination of the critical flashover voltage (CFO) of 17 single component and 90 combinations of two components were conducted. The acquired data were used to develop methods of predicting CFO levels of various multiple series electrical insulations. This paper illustrates the results and analyses of the classical primary insulation (porcelain), and of the modern-day insulation of polymers. It also presents the result of whether polymers may add or supplement insulation strength to the two dielectric combination using statistical methods. The paper also presents advantages and guidelines for the use of polymers to either replace or complement porcelain. This may help optimize the choice of dielectrics on distribution lines.

  1. Flammability and Photo-Stability of Selected Polymer Systems

    NASA Technical Reports Server (NTRS)

    Lo, Jeelin

    1981-01-01

    A systematic approach to the improvement of the flammability of epoxy resins, bisphenol-A polycarbonate poly(butylene terephthalate), and Nylon 6.6 by introducing halogens and loop functionality into the flame retardants is described. The phthalides (the loop functionality containing molecules) include 3,3-bis(4-bromophenyl)-phthalide, 3,3-bis(4-chlorophenyl)phthalide, and phenolphthalein. The phthalide containing epoxy resins are synthesized and characterized in comparison with the bisphenol-A epoxy resins in terms of flammability in the copolymer systems. The resins include diglycidyl ethers of phenolphthalein, bisphenol-A. tetrabromobisphenol-A, and tetraoromophenolphthalein. The vaporization of the phthalide additive in the polymers is observed in Thermal Gravimetric Analysis. The flame retardancy is primarily due to the presence of halogens. In the poly(butylene terephthalate) system, the cleavage of the C(sub aromatic) -B bond of the flame retardant additive enhances the crosslinking react ions between the aromatic rings resulting in an increase of char formation. In the epoxy resin systems, loop functionality contributes to char formation to a larger extent. The interaction between the epoxy resin and poly-(butylene terephthalate) follows the mechanism of insertion of the oxirane ring into the ester bond. This mechanism is studied by FT-IR. The investigation of the thermal properties of the char-forming phenol-formaldehyde resins is conducted to provide information for the systematic design of high temperature flame-resistant phenolics. NMR and FT-IR are used to characterize the oligomeric resins and the cured resins. The curing agents used in the study include formaldehyde, s-trioxane and terephthaloyl chloride. The brominated phenolic resins are found to have higher oxygen indices with lower char yields.

  2. Optical properties of polymer microtips investigated with workshop tomographic system

    NASA Astrophysics Data System (ADS)

    Dudek, Michał; Kujawińska, Małgorzata; Makowski, Piotr; Jaroszewicz, Leszek R.; Parat, Vincent

    2016-04-01

    We present a novel methodology for optical fiber polymer microtip manufacturing ant testing, which supports the structure optimization process through utilization of an optical diffraction tomography system based on the lateral shear digital holographic microscope. The most important functional parameter of an optical fiber microtip is the output beam distribution in the far-field region, which depends on geometrical properties and refractive index distribution within the microtip. These factors, in turn, are determined by the optical power distribution of the actinic light and the exposition time during the photopolymerization process. In order to obtain a desired light field distribution we propose to govern the manufacturing process by a hybrid opto-numerical methodology, which constitutes a convenient feedback loop for modification of the fabrication parameters. A single cycle of the proposed scheme includes numerical modeling, tomographic measurements and modifications of fabrication process. We introduced the real values of three-dimensional refractive index distribution of microtips into the finite-difference time-domain (FDTD) simulations, which leaded to controlled modification of technology parameters and finally to improvement of a functional parameter of microtips.

  3. Advanced Measurement Systems Available to PIWG Members

    NASA Technical Reports Server (NTRS)

    Anderson, Robert; Lei, Jih-Fen (Technical Monitor)

    2002-01-01

    It was developed advanced measurement technologies to meet NASA goals: reduce design cycle time, reduce emission, reduce testing time, increase safety. The technology are saving money. This technology are available now for technology transfer: optical diagnostics, the film technology and MEMS devices.

  4. Systems study of transport aircraft incorporating advanced aluminum alloys

    NASA Technical Reports Server (NTRS)

    Sakata, I. F.

    1982-01-01

    A study was performed to quantify the potential benefits of utilizing advanced aluminum alloys in commercial transport aircraft and to define the effort necessary to develop fully the alloys to a viable commercial production capability. The comprehensive investigation (1) established realistic advanced aluminum alloy property goals to maximize aircraft systems effectiveness (2) identified performance and economic benefits of incorporating the advanced alloy in future advanced technology commercial aircraft designs (3) provided a recommended plan for development and integration of the alloys into commercial aircraft production (4) provided an indication of the timing and investigation required by the metal producing industry to support the projected market and (5) evaluate application of advanced aluminum alloys to other aerospace and transit systems as a secondary objective. The results of the investigation provided a roadmap and identified key issues requiring attention in an advanced aluminum alloy and applications technology development program.

  5. Development of Carbon Dioxide Removal Systems for Advanced Exploration Systems

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Trinh, Diep; Gostowski, Rudy; King, Eric; Mattox, Emily M.; Watson, David; Thomas, John

    2012-01-01

    "NASA's Advanced Exploration Systems (AES) program is pioneering new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit" (NASA 2012). These forays beyond the confines of earth's gravity will place unprecedented demands on launch systems. They must not only blast out of earth's gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a crew over longer periods for exploration missions beyond earth's moon. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. Current efforts are focused on improving the current state-of-the-art systems utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. These development efforts combine testing of sub-scale systems and multi-physics computer simulations to evaluate candidate approaches, select the best performing options, and optimize the configuration of the selected approach, which is then implemented in a full-scale integrated atmosphere revitalization test. This paper describes the carbon dioxide (CO2) removal hardware design and sorbent screening and characterization effort in support of the Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project within the AES program. A companion paper discusses development of atmosphere revitalization models and simulations for this project.

  6. Renewability is not Enough: Recent Advances in the Sustainable Synthesis of Biomass-Derived Monomers and Polymers.

    PubMed

    Llevot, Audrey; Dannecker, Patrick-Kurt; von Czapiewski, Marc; Over, Lena C; Söyler, Zafer; Meier, Michael A R

    2016-08-01

    Taking advantage of the structural diversity of different biomass resources, recent efforts were directed towards the synthesis of renewable monomers and polymers, either for the substitution of petroleum-based resources or for the design of novel polymers. Not only the use of biomass, but also the development of sustainable chemical approaches is a crucial aspect for the production of sustainable materials. This review discusses the recent examples of chemical modifications and polymerizations of abundant biomass resources with a clear focus on the sustainability of the described processes. Topics such as synthetic methodology, catalysis, and development of new solvent systems or greener alternative reagents are addressed. The chemistry of vegetable oil derivatives, terpenes, lignin, carbohydrates, and sugar-based platform chemicals was selected to highlight the trends in the active field of a sustainable use of renewable resources. PMID:27355829

  7. Design and Experimental Evaluation on an Advanced Multisource Energy Harvesting System for Wireless Sensor Nodes

    PubMed Central

    Li, Hao; Zhang, Gaofei; Ma, Rui; You, Zheng

    2014-01-01

    An effective multisource energy harvesting system is presented as power supply for wireless sensor nodes (WSNs). The advanced system contains not only an expandable power management module including control of the charging and discharging process of the lithium polymer battery but also an energy harvesting system using the maximum power point tracking (MPPT) circuit with analog driving scheme for the collection of both solar and vibration energy sources. Since the MPPT and the power management module are utilized, the system is able to effectively achieve a low power consumption. Furthermore, a super capacitor is integrated in the system so that current fluctuations of the lithium polymer battery during the charging and discharging processes can be properly reduced. In addition, through a simple analog switch circuit with low power consumption, the proposed system can successfully switch the power supply path according to the ambient energy sources and load power automatically. A practical WSNs platform shows that efficiency of the energy harvesting system can reach about 75–85% through the 24-hour environmental test, which confirms that the proposed system can be used as a long-term continuous power supply for WSNs. PMID:25032233

  8. Advanced Aromatic Polymers with Excellent Antiatomic Oxygen Performance Derived from Molecular Precursor Strategy and Copolymerization of Polyhedral Oligomeric Silsesquioxane.

    PubMed

    Wang, Pei; Tang, Yusheng; Yu, Zhen; Gu, Junwei; Kong, Jie

    2015-09-16

    In this contribution, the advanced aromatic polymers with excellent antiatomic oxygen (AO) performance were designed and synthesized using molecular precursor strategy and copolymerization of polyhedral oligomeric silsesquioxane (POSS). A soluble poly(p-phenylene benzobisoxazole) (PBO) precursor, that is, TBS-PBO (tert-butyldimethylsilyl was denoted as TBS), was designed to overcome the poor solubility of PBO in organic solvents. Then the new copolymer of TBS-PBO-POSS was synthesized by the copolymerization of TBS-PBO and POSS, which possessed good solubility and film-forming ability in common organic solvents, such as N-methylpyrrolidone, N,N-dimethylacetamide, and dimethyl sulfoxide. More importantly, the TBS-PBO-POSS films exhibited outstanding antiatomic oxygen properties because of the incorporation of POSS monomers with cagelike structure into the main chain of copolymer, which drastically reduced the AO-induced erosion owing to the formation of the passivating silica layer on the surface of polymers. When the TBS-PBO-POSS films were exposed to AO effective fluences of 1.5495×10(20) atom cm(-2) (5 h) and 4.6486×10(20) atom cm(-2) (15 h), the relative mass loss was merely 0.19% and 0.41%, respectively. This work provides a new perspective and efficient strategy for the molecular design of aromatic heterocyclic polymers possessing excellent combination properties including processing convenience and antioxidative and mechanical properties, which can be employed as potential candidates to endure the aggressive environment encountered in low earth orbits. PMID:26322523

  9. Impact of Advance Control on Microturbine Generation System Performance

    NASA Astrophysics Data System (ADS)

    Kamil Mat Hussin, Ahmad; Zamri Che Wanik, Mohd

    2013-06-01

    Advance control employed in microturbine generation system (MTGS) is expected to improve its performance in responding to grid faults. This paper compares the effect of advance control of MTGS power conversion topology on the performance in riding through the grid faults. The analysis and investigation study through simulation shows there is no significant different on MTGS output performance even advance control is employed for its rectifier.

  10. Fabrication of Ruthenium Nanoparticles in Porous Organic Polymers: Towards Advanced Heterogeneous Catalytic Nanoreactors.

    PubMed

    Mondal, John; Kundu, Sudipta K; Hung Ng, Wilson Kwok; Singuru, Ramana; Borah, Parijat; Hirao, Hajime; Zhao, Yanli; Bhaumik, Asim

    2015-12-21

    A novel strategy has been adopted for the construction of a copolymer of benzene-benzylamine-1 (BBA-1), which is a porous organic polymer (POP) with a high BET surface area, through Friedel-Crafts alkylation of benzylamine and benzene by using formaldehyde dimethyl acetal as a cross-linker and anhydrous FeCl3 as a promoter. Ruthenium nanoparticles (Ru NPs) were successfully distributed in the interior cavities of polymers through NaBH4, ethylene glycol, and hydrothermal reduction routes, which delivered Ru-A, Ru-B, and Ru-C materials, respectively, and avoided aggregation of metal NPs. Homogeneous dispersion, the nanoconfinement effect of the polymer, and the oxidation state of Ru NPs were verified by employing TEM, energy-dispersive X-ray spectroscopy mapping, cross polarization magic-angle spinning (13)C NMR spectroscopy, and X-ray photoelectron spectroscopy analytical tools. These three new Ru-based POP materials exhibited excellent catalytic performance in the hydrogenation of nitroarenes at RT (with a reaction time of only ≈ 30 min), with high conversion, selectivity, stability, and recyclability for several catalytic cycles, compared with other traditional materials, such as Ru@C, Ru@SiO2, and Ru@TiO2, but no clear agglomeration or loss of catalytic activity was observed. The high catalytic performance of the ruthenium-based POP materials is due to the synergetic effect of nanoconfinement and electron donation offered by the 3D POP network. DFT calculations showed that hydrogenation of nitrobenzene over the Ru (0001) catalyst surface through a direct reaction pathway is more favorable than that through an indirect reaction pathway. PMID:26572500

  11. Photo-Curable Polymer Blend Dielectrics for Advancing Organic Field-Effect Transistor Applications

    SciTech Connect

    S Kim; K Hong; M Jang; J Jang; J Anthony; H Yang; C Park

    2011-12-31

    A solution method of photo-curable and -patternable polymer gate dielectrics was introduced by using blend solutions of poly(4-dimethylsilyl styrene) (PDMSS) and poly(melamine-co-formaldehyde) acrylate (PMFA). The fabrication was optimized to produce a smooth hydrophobic gate dielectric with good insulating and solvent-resistant properties. On the optimized PDMSS/PMFA blend gate dielectric, pentacene could grow into highly ordered structure, showing high electric performances for the resulting OFETs, as well as PTCDI-C13 and TES-ADT.

  12. Hot Melt Extruded Amorphous Solid Dispersion of Posaconazole with Improved Bioavailability: Investigating Drug-Polymer Miscibility with Advanced Characterisation

    PubMed Central

    Amin, Purnima

    2014-01-01

    Invasive antifungal infections are reasons for morbidity and mortality in immunogenic patients worldwide. Posaconazole is a most promising antifungal agent against all types of invasive infections with high % of cure rate. The marketed suspension formulation has low bioavailability and is needed to be taken with food. In this paper, PCZ hot melt extruded amorphous solid dispersion (SD) with immediate release and improved bioavailability was prepared using Soluplus (Sol) as primary carrier for solubilization. Surfactants such as PEG 400, Lutrol F27, Lutrol F68, and TPGS are also used in combination with Soluplus to improve the physicochemical performance of the formulation when it comes in contact with GI (gastrointestinal) fluid. Drug-polymer miscibility of SD was investigated using advanced techniques. In the in vivo study, the AUC(0–72) and Cmax of PCZ/Soluplus were 11.5 and 11.74 time higher than those of pure PCZ. The formulation of the extrudate SD had an AUC(0–72) and Cmax higher than those with the commercial capsule (Noxafil). Molecular dynamic (MD) simulation studies were carried out using in silico molecular modelling to understand the drug-polymer intermolecular behaviour. The results of this research ensure enhanced dissolution and bioavailability of the solid dispersion of PCZ prepared by HME compared with the PCZ suspension. PMID:25143935

  13. Engineered glycated amino dendritic polymers as specific nonviral gene delivery vectors targeting the receptor for advanced glycation end products.

    PubMed

    Giron-Gonzalez, M Dolores; Morales-Portillo, Arturo; Salinas-Castillo, Alfonso; Lopez-Jaramillo, F Javier; Hernandez-Mateo, Fernando; Santoyo-Gonzalez, Francisco; Salto-Gonzalez, Rafael

    2014-06-18

    The receptor for advanced glycation end products (RAGE) is involved in diabetes or angiogenesis in tumors. Under pathological conditions, RAGE is overexpressed and upon ligand binding and internalization stimulates signaling pathways that promote cell proliferation. In this work, amino dendritic polymers PEI 25 kDa and alkylated derivatives of PAMAM-G2 were engineered by the nonenzymatic Maillard glycation reaction to generate novel AGE-containing gene delivery vectors targeting the RAGE. The glycated dendritic polymers were easily prepared and retained the capability to bind and protect DNA from endonucleases. Furthermore, while glycation decreased the transfection efficiency of the dendriplexes in CHO-k1 cells which do not express RAGE, glycated dendriplexes acted as efficient transfection reagents in CHO-k1 cells which stably express recombinant RAGE. In addition, preincubation with BSA-AGEs, a natural ligand of the RAGE, or dansyl cadaverine, an inhibitor of the RAGE internalization, blocked transfection, confirming their specificity toward RAGE. The results were confirmed in NRK and RAW264.7 cell lines, which naturally express the receptor. The glycated compounds retain their transfection efficiency in the presence of serum and promote in vivo transfection in a mouse model. Accordingly, RAGE is a suitable molecular target for the development of site-directed engineered glycated nonviral gene vectors. PMID:24852962

  14. Neutron scattering in polymer physics

    NASA Astrophysics Data System (ADS)

    Richter, D.

    2000-03-01

    By example this short review presents recent scientific advances which were achieved by the application of neutron scattering to polymer systems, thereby, keeping in mind also practical applications. We first focus on experiments on the structure and morphology of polymer systems covering conformational studies, investigations on polymer-microemulsions systems and the observation of aggregation states in living polymerization. Thereafter, we present recent results in the field of polymer dynamics. We begin with local motions which are behind the classical relaxation processes in polymer melts. Then we relate to universal dynamics, we address the Rouse model and its limits, present new results on the dynamic miscibility in blends and display the latest investigations on entanglement dynamics. Finally, we report first observations of ripplon excitations of phase boundaries in diblock copolymer melts.

  15. Proliferation resistance of advanced nuclear energy systems

    SciTech Connect

    Pierpoint, Lara; Kazimi, Mujid; Hejzlar, Pavel

    2007-07-01

    A methodology for evaluating the proliferation resistance of advanced nuclear fuel cycles is presented. The methodology, based on multi-attribute utility theory (MAUT) is intended as a computerized assessment for fuel cycles at their earliest stages of development (i.e. when detailed facility design information is not available). Preliminary results suggest that the methodology may be useful in identifying sources of proliferation vulnerability within different fuel cycles. Of the fuel cycles and segments studied, the fabrication step of the Once- Through fuel cycle and the reprocessing step of the MOX fuel cycle present the greatest vulnerability. The Advanced Burner Reactor (ABR) fuel cycle with conversion ratio 0.0 appears to be the overall safest fuel cycle from a proliferation protection standpoint. (authors)

  16. Advanced Microgravity Acceleration Measurement Systems (AMAMS) Being Developed

    NASA Technical Reports Server (NTRS)

    Sicker, Ronald J.; Kacpura, Thomas J.

    2003-01-01

    The Advanced Microgravity Acceleration Measurement Systems (AMAMS) project is part of NASA s Instrument Technology Development program to develop advanced sensor systems. The primary focus of the AMAMS project is to develop microelectromechanical systems (MEMS) for acceleration sensor systems to replace existing electromechanical sensor systems presently used to assess relative gravity levels aboard spacecraft. These systems are used to characterize both vehicle and payload responses to low-gravity vibroacoustic environments. The collection of microgravity acceleration data is useful to the microgravity life sciences, microgravity physical sciences, and structural dynamics communities. The inherent advantages of semiconductor-based systems are reduced size, mass, and power consumption, with enhanced long-term calibration stability.

  17. Advanced space power PEM fuel cell systems

    NASA Technical Reports Server (NTRS)

    Vanderborgh, N. E.; Hedstrom, J.; Huff, J. R.

    1989-01-01

    A model showing mass and heat transfer in proton exchange membrane (PEM) single cells is presented. For space applications, stack operation requiring combined water and thermal management is needed. Advanced hardware designs able to combine these two techniques are available. Test results are shown for membrane materials which can operate with sufficiently fast diffusive water transport to sustain current densities of 300 ma per square centimeter. Higher power density levels are predicted to require active water removal.

  18. Advanced lubrication systems and materials. Final report

    SciTech Connect

    Hsu, S.

    1998-05-07

    This report described the work conducted at the National Institute of Standards and Technology under an interagency agreement signed in September 1992 between DOE and NIST for 5 years. The interagency agreement envisions continual funding from DOE to support the development of fuel efficient, low emission engine technologies in terms of lubrication, friction, and wear control encountered in the development of advanced transportation technologies. However, in 1994, the DOE office of transportation technologies was reorganized and the tribology program was dissolved. The work at NIST therefore continued at a low level without further funding from DOE. The work continued to support transportation technologies in the development of fuel efficient, low emission engine development. Under this program, significant progress has been made in advancing the state of the art of lubrication technology for advanced engine research and development. Some of the highlights are: (1) developed an advanced high temperature liquid lubricant capable of sustaining high temperatures in a prototype heat engine; (2) developed a novel liquid lubricant which potentially could lower the emission of heavy duty diesel engines; (3) developed lubricant chemistries for ceramics used in the heat engines; (4) developed application maps for ceramic lubricant chemistry combinations for design purpose; and (5) developed novel test methods to screen lubricant chemistries for automotive air-conditioning compressors lubricated by R-134a (Freon substitute). Most of these findings have been reported to the DOE program office through Argonne National Laboratory who manages the overall program. A list of those reports and a copy of the report submitted to the Argonne National Laboratory is attached in Appendix A. Additional reports have also been submitted separately to DOE program managers. These are attached in Appendix B.

  19. The intelligent user interface for NASA's advanced information management systems

    NASA Technical Reports Server (NTRS)

    Campbell, William J.; Short, Nicholas, Jr.; Rolofs, Larry H.; Wattawa, Scott L.

    1987-01-01

    NASA has initiated the Intelligent Data Management Project to design and develop advanced information management systems. The project's primary goal is to formulate, design and develop advanced information systems that are capable of supporting the agency's future space research and operational information management needs. The first effort of the project was the development of a prototype Intelligent User Interface to an operational scientific database, using expert systems and natural language processing technologies. An overview of Intelligent User Interface formulation and development is given.

  20. The Role of Intelligent Agents in Advanced Information Systems

    NASA Technical Reports Server (NTRS)

    Kerschberg, Larry

    1999-01-01

    In this presentation we review the current ongoing research within George Mason University's (GMU) Center for Information Systems Integration and Evolution (CISE). We define characteristics of advanced information systems, discuss a family of agents for such systems, and show how GMU's Domain modeling tools and techniques can be used to define a product line Architecture for configuring NASA missions. These concepts can be used to define Advanced Engineering Environments such as those envisioned for NASA's new initiative for intelligent design and synthesis environments.

  1. Advanced Turbine Systems Program industrial system concept development

    SciTech Connect

    Gates, S.

    1995-12-31

    Solar approached Phase II of ATS program with the goal of 50% thermal efficiency. An intercolled and recuperated gas turbine was identified as the ultimate system to meet this goal in a commercial gas turbine environment. With commercial input from detailed market studies and DOE`s ATS program, Solar redefined the company`s proposed ATS to fit both market and sponsor (DOE) requirements. Resulting optimized recuperated gas turbine will be developed in two sizes, 5 and 15 MWe. It will show a thermal efficiency of about 43%, a 23% improvement over current industrial gas turbines. Other ATS goals--emissions, RAMD (reliability, availability, maintainability, durability), cost of power--will be met or exceeded. During FY95, advanced development of key materials, combustion and component technologies proceeded to the point of acceptance for inclusion in ATS Phase III.

  2. A new system for crack closure of cementitious materials using shrinkable polymers

    SciTech Connect

    Jefferson, Anthony; Joseph, Christopher; Lark, Robert; Isaacs, Ben; Dunn, Simon; Weager, Brendon

    2010-05-15

    This paper presents details of an original crack-closure system for cementitious materials using shrinkable polymer tendons. The system involves the incorporation of unbonded pre-oriented polymer tendons in cementitious beams. Crack closure is achieved by thermally activating the shrinkage mechanism of the restrained polymer tendons after the cement-based material has undergone initial curing. The feasibility of the system is demonstrated in a series of small scale experiments on pre-cracked prismatic mortar specimens. The results from these tests show that, upon activation, the polymer tendon completely closes the preformed macro-cracks and imparts a significant stress across the crack faces. The potential of the system to enhance the natural autogenous crack healing process and generally improve the durability of concrete structures is addressed.

  3. Quantum efficiency of PAG decomposition in different polymer matrices at advanced lithographic wavelengths

    NASA Astrophysics Data System (ADS)

    Fedynyshyn, Theodore H.; Sinta, Roger F.; Mowers, William A.; Cabral, Alberto

    2003-06-01

    The Dill ABC parameters for optical resists are typically determined by measuring the change in the intensity of transmitted light at the wavelength of interest as a function of incident energy. The effectiveness of the experiment rests with the fact that the resist optical properties change with exposure and that the optical properties are directly related to the concentration of PAG compound. These conditions are not typically satisfied in CA resists and thus C is unobtainable by this method. FT-IR spectroscopy can directly measure changes in the photoactive species by isolating and measuring absorbance peaks unique to the photoactive species. We employed the ProABC software, specially modified to allow FT-IR absorbance input, to extract ABS parameters through a best fit of the lithography model to experimental data. The quantum efficiency of PAG decomposition at 157-, 193-, and 248-nm was determined for four diazomethane type PAGs in four different polymer matrices. It was found that both the Dill C parameter and the quantum efficiency for all PAGs increased as wavelength decreased, but that the magnitude of the increase was strongly dependent on the polymer matrix.

  4. Conductive Polymer-Coated VS4 Submicrospheres As Advanced Electrode Materials in Lithium-Ion Batteries.

    PubMed

    Zhou, Yanli; Li, Yanlu; Yang, Jing; Tian, Jian; Xu, Huayun; Yang, Jian; Fan, Weiliu

    2016-07-27

    VS4 as an electrode material in lithium-ion batteries holds intriguing features like high content of sulfur and one-dimensional structure, inspiring the exploration in this field. Herein, VS4 submicrospheres have been synthesized via a simple solvothermal reaction. However, they quickly degrade upon cycling as an anode material in lithium-ion batteries. So, three conductive polymers, polythiophene (PEDOT), polypyrrole (PPY), and polyaniline (PANI), are coated on the surface to improve the electron conductivity, suppress the diffusion of polysulfides, and modify the interface between electrode/electrolyte. PANI is the best in the polymers. It improves the Coulombic efficiency to 86% for the first cycle and keeps the specific capacity at 755 mAh g(-1) after 50 cycles, higher than the cases of naked VS4 (100 mAh g(-1)), VS4@PEDOT (318 mAh g(-1)), and VS4@PPY (448 mAh g(-1)). The good performances could be attributed to the improved charge-transfer kinetics and the strong interaction between PANI and VS4 supported by theoretical simulation. The discharge voltage ∼2.0 V makes them promising cathode materials. PMID:27377263

  5. Support for the Advanced Polymers Beamline at the National Synchrotron Light Source

    SciTech Connect

    Hsiao, Benjamin S

    2008-10-01

    The primary focus of the X27C beamline is to investigate frontier polymer science and engineering problems with emphasis on real-time studies of structures, morphologies and dynamics from atomic, nanoscopic, microscopic to mesoscopic scales using simultaneous small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) techniques. The scientific merit of this project is as follows. Currently, many unique sample chambers for in-situ synchrotron studies, developed by the PI (B. Hsiao) and Co-PI (B. Chu), are available for general users of X27C at NSLS. These instruments include a gel/melt spinning apparatus, a continuous fiber drawing apparatus, a tensile stretching apparatus, a high pressure X-ray cell using supercritical carbon dioxide, a parallel plate strain-controlled shear stage and a dynamic rheometer for small-strain oscillatory deformation study. Based on the use of these instruments in combination with synchrotron X-rays, many new insights into the relationships between processing and structure have been obtained in recent years. The broader impact of this project is as follows. The X27C beamline is the first synchrotron facility in the United States dedicated to chemistry/materials research (with emphasis on polymers). The major benefit of this facility to the materials community is that no extensive synchrotron experience and equipment preparation are required from general users to carry out cutting-edge experiments.

  6. Advanced photovoltaic system simulator to demonstrate the performance of advanced photovoltaic cells and devices

    SciTech Connect

    Mrig, L.; DeBlasio, R.; O'Sullivan, G.A.; Tomko, R.P.

    1983-05-01

    This paper describes a photovoltaic system simulator for characterizing and evaluating the performance of advanced photovoltaic cells, modules, and arrays as well as for simulating the operation of advanced conceptual photovoltaic systems. The system simulator is capable of extrapolating the performance from a single laboratory cell, or of a module to power levels up to 10 kW. The major subsystems comprising the system simulator are (1) Solar Array Simulator, (2) Power Conditioning Unit, (3) Load Controller and Resistive Load Unit, (4) Data Acquisition and Control Unit, and (5) Cell Test Bed.

  7. Advanced NSTS propulsion system verification study

    NASA Technical Reports Server (NTRS)

    Wood, Charles

    1989-01-01

    The merits of propulsion system development testing are discussed. The existing data base of technical reports and specialists is utilized in this investigation. The study encompassed a review of all available test reports of propulsion system development testing for the Saturn stages, the Titan stages, and the Space Shuttle main propulsion system. The knowledge on propulsion system development and system testing available from specialists and managers was also 'tapped' for inclusion.

  8. Advanced Gas Turbine (AGT) powertrain system

    NASA Technical Reports Server (NTRS)

    Helms, H. E.; Kaufeld, J.; Kordes, R.

    1981-01-01

    A 74.5 kW(100 hp) advanced automotive gas turbine engine is described. A design iteration to improve the weight and production cost associated with the original concept is discussed. Major rig tests included 15 hours of compressor testing to 80% design speed and the results are presented. Approximately 150 hours of cold flow testing showed duct loss to be less than the design goal. Combustor test results are presented for initial checkout tests. Turbine design and rig fabrication is discussed. From a materials study of six methods to fabricate rotors, two have been selected for further effort. A discussion of all six methods is given.

  9. Utilizing advanced polymerization techniques for simplifying polymer grafting from silica colloidal crystal substrates

    NASA Astrophysics Data System (ADS)

    Yerneni, Charu K.

    Polyacrylamide has been well established as a biocompatible material when Polyacrylamide gel electrophoresis (PAGE) came into existence in the 1960s. Under aqueous buffer conditions it becomes non-adsorptive to proteins and due to its molecular level pore forming nature could be used in size based biomolecule separations. Since then considerable research has been done to explore the non-adsorptive nature of polyacrylamide on a platform or substrate. Attempts were made to grow polyacrylamide chains from silica as a substrate which can then be used in various protein separation techniques. Based on an ionic polymerization method which was used for gel casting in PAGE, polymers were grown on silica gel. Though considerable thickness could be achieved, polymerization was not just confined to the surface. Therefore a rigid polymer brush layer could not be achieved. Atom transfer radical polymerization (ATRP) method showed the solution to this problem. Polymer brush layers with acceptable thickness could now be achieved for growing polyacrylamide from silica gel. Yet it still suffered from several disadvantages such as the need of an inert atmosphere for polymerization and limited thickness. Many developments have taken place in the past decade which led to improvements in substrate and polymerization methods. This research used non porous sub-micron silica as the substrate and AGET ATRP (Activator generated electron transfer atom transfer radical polymerization) for surface grafting polyacrylamide. Non porous submicron silica has been shown to be a better stationary phase substrate for protein separations than conventional substrates. AGET ATRP enables polymerization to be performed under ambient conditions and in water based solutions which gives thicknesses much higher than conventional ATRP. Data from various analytical techniques showed that within the experimental range the polymerization is linear and has decent control. This means silica nanoparticles coated with

  10. Conceptual design study: Forest Fire Advanced System Technology (FFAST)

    NASA Technical Reports Server (NTRS)

    Nichols, J. D.; Warren, J. R.

    1986-01-01

    An integrated forest fire detection and mapping system that will be based upon technology available in the 1990s was defined. Uncertainties in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include thermal infrared, linear array detectors, automatic georeferencing and signal processing, geosynchronous satellite communication links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. A preferred system configuration was defined that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.

  11. Modeling the Behaviour of an Advanced Material Based Smart Landing Gear System for Aerospace Vehicles

    SciTech Connect

    Varughese, Byji; Dayananda, G. N.; Rao, M. Subba

    2008-07-29

    The last two decades have seen a substantial rise in the use of advanced materials such as polymer composites for aerospace structural applications. In more recent years there has been a concerted effort to integrate materials, which mimic biological functions (referred to as smart materials) with polymeric composites. Prominent among smart materials are shape memory alloys, which possess both actuating and sensory functions that can be realized simultaneously. The proper characterization and modeling of advanced and smart materials holds the key to the design and development of efficient smart devices/systems. This paper focuses on the material characterization; modeling and validation of the model in relation to the development of a Shape Memory Alloy (SMA) based smart landing gear (with high energy dissipation features) for a semi rigid radio controlled airship (RC-blimp). The Super Elastic (SE) SMA element is configured in such a way that it is forced into a tensile mode of high elastic deformation. The smart landing gear comprises of a landing beam, an arch and a super elastic Nickel-Titanium (Ni-Ti) SMA element. The landing gear is primarily made of polymer carbon composites, which possess high specific stiffness and high specific strength compared to conventional materials, and are therefore ideally suited for the design and development of an efficient skid landing gear system with good energy dissipation characteristics. The development of the smart landing gear in relation to a conventional metal landing gear design is also dealt with.

  12. Modeling the Behaviour of an Advanced Material Based Smart Landing Gear System for Aerospace Vehicles

    NASA Astrophysics Data System (ADS)

    Varughese, Byji; Dayananda, G. N.; Rao, M. Subba

    2008-07-01

    The last two decades have seen a substantial rise in the use of advanced materials such as polymer composites for aerospace structural applications. In more recent years there has been a concerted effort to integrate materials, which mimic biological functions (referred to as smart materials) with polymeric composites. Prominent among smart materials are shape memory alloys, which possess both actuating and sensory functions that can be realized simultaneously. The proper characterization and modeling of advanced and smart materials holds the key to the design and development of efficient smart devices/systems. This paper focuses on the material characterization; modeling and validation of the model in relation to the development of a Shape Memory Alloy (SMA) based smart landing gear (with high energy dissipation features) for a semi rigid radio controlled airship (RC-blimp). The Super Elastic (SE) SMA element is configured in such a way that it is forced into a tensile mode of high elastic deformation. The smart landing gear comprises of a landing beam, an arch and a super elastic Nickel-Titanium (Ni-Ti) SMA element. The landing gear is primarily made of polymer carbon composites, which possess high specific stiffness and high specific strength compared to conventional materials, and are therefore ideally suited for the design and development of an efficient skid landing gear system with good energy dissipation characteristics. The development of the smart landing gear in relation to a conventional metal landing gear design is also dealt with.

  13. Observation of dynamic equilibrium cluster phase in nanoparticle-polymer system

    NASA Astrophysics Data System (ADS)

    Kumar, Sugam; Mehan, S.; Aswal, V. K.; Schwein, R.

    2016-05-01

    Small-angle neutron scattering (SANS) and dynamic light scattering (DLS) have been used to investigate the existence of a cluster phase in a nanoparticle-polymer system. The nanoparticle-polymer system shows an interesting reentrant phase behavior where the charge stabilized silica nanoparticles undergo particle clustering and back to individual nanoparticles as a function of polymer concentration. This kind of phase behavior is believed to be directed by opposing attractive and repulsive interactions present in the system. The phase behavior shows two narrow regions of polymer concentration immediately before and after the two-phase formation indicating the possibility of the existence of some equilibrium clusters. DLS results show a much higher size of particles than individuals in these two regions which remains unchanged even after dilution. The SANS data show the evolution of attraction with increased volume fraction of the particles supporting the dynamic nature of these clusters.

  14. Systemic Chemotherapy in Advanced Pancreatic Cancer

    PubMed Central

    Lee, Hee Seung; Park, Seung Woo

    2016-01-01

    Pancreatic cancer remains one of the most lethal cancers. These patients often have multiple symptoms, and integrated supportive care is critical in helping them remain well for as long as possible. Fluorouracil-based chemotherapy is known to improve overall survival (OS) by approximately 3 months, compared to the best supportive care alone. A 1997 study comparing gemcitabine and fluorouracil treatment of advanced pancreatic cancer patients showed an improvement in OS of 1 month in patients receiving gemcitabine. Over the next 10 years, multiple randomized studies compared single-agent gemcitabine with combination chemotherapy and showed no effective survival improvement. However, the addition of erlotinib, an epidermal growth factor receptor (EGFR) inhibitor, was associated with a significant improvement in OS of approximately 2 weeks. However, adoption of this regimen has not been widespread because of its limited effect and added toxicity. Two clinical trials have recently prolonged OS in advanced pancreatic cancer patients by almost 1 year. The first compared FOLFIRINOX with gemcitabine alone, and was associated with a significant improvement in median survival. The second compared gemcitabine and nab-paclitaxel with gemcitabine alone, and was associated with improvements in OS. At present, these regimens are considered standard treatment for patients with good performance statuses. PMID:27114434

  15. Advanced Solar Cells for Satellite Power Systems

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.; Weinberg, Irving

    1994-01-01

    The multiple natures of today's space missions with regard to operational lifetime, orbital environment, cost and size of spacecraft, to name just a few, present such a broad range of performance requirements to be met by the solar array that no single design can suffice to meet them all. The result is a demand for development of specialized solar cell types that help to optimize overall satellite performance within a specified cost range for any given space mission. Historically, space solar array performance has been optimized for a given mission by tailoring the features of silicon solar cells to account for the orbital environment and average operating conditions expected during the mission. It has become necessary to turn to entirely new photovoltaic materials and device designs to meet the requirements of future missions, both in the near and far term. This paper will outline some of the mission drivers and resulting performance requirements that must be met by advanced solar cells, and provide an overview of some of the advanced cell technologies under development to meet them. The discussion will include high efficiency, radiation hard single junction cells; monolithic and mechanically stacked multiple bandgap cells; and thin film cells.

  16. Piezoelectric Polymers

    NASA Technical Reports Server (NTRS)

    Harrison, J. S.; Ounaies, Z.; Bushnell, Dennis M. (Technical Monitor)

    2001-01-01

    The purpose of this review is to detail the current theoretical understanding of the origin of piezoelectric and ferroelectric phenomena in polymers; to present the state-of-the-art in piezoelectric polymers and emerging material systems that exhibit promising properties; and to discuss key characterization methods, fundamental modeling approaches, and applications of piezoelectric polymers. Piezoelectric polymers have been known to exist for more than forty years, but in recent years they have gained notoriety as a valuable class of smart materials.

  17. Status report on the Advanced Light Source control system

    SciTech Connect

    Magyary, S.; Chin, M.; Fahmie, M.; Lancaster, H.; Molinari, P.; Robb, A.; Timossi, C.; Young, J.

    1991-11-11

    This paper is a status report on the ADVANCED LIGHT SOURCE (ALS) control system. The current status, performance data, and future plans will be discussed. Manpower, scheduling, and costs issues are addressed.

  18. Transcription of the Workshop on General Aviation Advanced Avionics Systems

    NASA Technical Reports Server (NTRS)

    Tashker, M. (Editor)

    1975-01-01

    Papers are presented dealing with the design of reliable, low cost, advanced avionics systems applicable to general aviation in the 1980's and beyond. Sensors, displays, integrated circuits, microprocessors, and minicomputers are among the topics discussed.

  19. Advanced photovoltaic power system technology for lunar base applications

    NASA Technical Reports Server (NTRS)

    Brinker, David J.; Flood, Dennis J.

    1992-01-01

    The development of an advanced photovoltaic power system that would have application for a manned lunar base is currently planned under the Surface Power element of Pathfinder. Significant mass savings over state-of-the-art photovoltaic/battery systems are possible with the use of advanced lightweight solar arrays coupled with regenerative fuel cell storage. The solar blanket, using either ultrathin GaAs or amorphous silicon solar cells, would be integrated with a reduced-g structure. Regenerative fuel cells with high-pressure gas storage in filament-wound tanks are planned for energy storage. An advanced PV/RFC power system is a leading candidate for a manned lunar base as it offers a tremendous weight advantage over state-of-the-art photovoltaic/battery systems and is comparable in mass to other advanced power generation technologies.

  20. Advanced Technology Display House. Volume 2: Energy system design concepts

    NASA Technical Reports Server (NTRS)

    Maund, D. H.

    1981-01-01

    The preliminary design concept for the energy systems in the Advanced Technology Display House is analyzed. Residential energy demand, energy conservation, and energy concepts are included. Photovoltaic arrays and REDOX (reduction oxidation) sizes are discussed.