WorldWideScience

Sample records for surface enhancement technology

  1. A Novel RFID Sensing System Using Enhanced Surface Wave Technology for Battery Exchange Stations

    OpenAIRE

    Yeong-Lin Lai; Li-Chih Chang; Tai-Hwa Liu; Yi-Chun Sung; Cheng-Lun Yin

    2014-01-01

    This paper presents a novel radio-frequency identification (RFID) sensing system using enhanced surface wave technology for battery exchange stations (BESs) of electric motorcycles. Ultrahigh-frequency (UHF) RFID technology is utilized to automatically track and manage battery and user information without manual operation. The system includes readers, enhanced surface wave leaky cable antennas (ESWLCAs), coupling cable lines (CCLs), and small radiation patches (SRPs). The RFID sensing system ...

  2. A Novel RFID Sensing System Using Enhanced Surface Wave Technology for Battery Exchange Stations

    Directory of Open Access Journals (Sweden)

    Yeong-Lin Lai

    2014-01-01

    Full Text Available This paper presents a novel radio-frequency identification (RFID sensing system using enhanced surface wave technology for battery exchange stations (BESs of electric motorcycles. Ultrahigh-frequency (UHF RFID technology is utilized to automatically track and manage battery and user information without manual operation. The system includes readers, enhanced surface wave leaky cable antennas (ESWLCAs, coupling cable lines (CCLs, and small radiation patches (SRPs. The RFID sensing system overcomes the electromagnetic interference in the metallic environment of a BES cabinet. The developed RFID sensing system can effectively increase the efficiency of BES operation and promote the development of electric vehicles which solve the problem of air pollution as well as protect the environment of the Earth.

  3. Development of batch producible hot embossing 3D nanostructured surface-enhanced Raman scattering chip technology

    Science.gov (United States)

    Huang, Chu-Yu; Tsai, Ming-Shiuan

    2017-09-01

    The main purpose of this study is to develop a batch producible hot embossing 3D nanostructured surface-enhanced Raman chip technology for high sensitivity label-free plasticizer detection. This study utilizing the AAO self-assembled uniform nano-hemispherical array barrier layer as a template to create a durable nanostructured nickel mold. With the hot embossing technique and the durable nanostructured nickel mold, we are able to batch produce the 3D Nanostructured Surface-enhanced Raman Scattering Chip with consistent quality. In addition, because of our SERS chip can be fabricated by batch processing, the fabrication cost is low. Therefore, the developed method is very promising to be widespread and extensively used in rapid chemical and biomolecular detection applications.

  4. Integrating Technology-Enhanced Collaborative Surfaces and Gamification for the Next Generation Classroom

    Science.gov (United States)

    Barneva, Reneta P.; Kanev, Kamen; Kapralos, Bill; Jenkin, Michael; Brimkov, Boris

    2017-01-01

    We place collaborative student engagement in a nontraditional perspective by considering a novel, more interactive educational environment and explaining how to employ it to enhance student learning. To this end, we explore modern technological classroom enhancements as well as novel pedagogical techniques which facilitate collaborative learning.…

  5. Surface-Enhanced Raman Scattering-Based Immunoassay Technologies for Detection of Disease Biomarkers

    Directory of Open Access Journals (Sweden)

    Joseph Smolsky

    2017-01-01

    Full Text Available Detection of biomarkers is of vital importance in disease detection, management, and monitoring of therapeutic efficacy. Extensive efforts have been devoted to the development of novel diagnostic methods that detect and quantify biomarkers with higher sensitivity and reliability, contributing to better disease diagnosis and prognosis. When it comes to such devastating diseases as cancer, these novel powerful methods allow for disease staging as well as detection of cancer at very early stages. Over the past decade, there have been some advances in the development of platforms for biomarker detection of diseases. The main focus has recently shifted to the development of simple and reliable diagnostic tests that are inexpensive, accurate, and can follow a patient’s disease progression and therapy response. The individualized approach in biomarker detection has been also emphasized with detection of multiple biomarkers in body fluids such as blood and urine. This review article covers the developments in Surface-Enhanced Raman Scattering (SERS and related technologies with the primary focus on immunoassays. Limitations and advantages of the SERS-based immunoassay platform are discussed. The article thoroughly describes all components of the SERS immunoassay and highlights the superior capabilities of SERS readout strategy such as high sensitivity and simultaneous detection of a multitude of biomarkers. Finally, it introduces recently developed strategies for in vivo biomarker detection using SERS.

  6. Enhancement of biocompatibility of nickel-titanium by laser surface modification technology

    Science.gov (United States)

    Ng, Ka Wai

    Nickel Titanium is a relatively new biomaterial that has attracted research interest for biomedical application. The good biocompatibility with specific functional properties of shape memory effect and superelasticity creates a smart material for medical applications. However, there are still concerns on nickel ion release of this alloy if it is going to be implanted for a long time. Nickel ion is carcinogenic and also causes allergic response and degeneration of muscle tissue. The subsequent release of Ni+ ions into the body system is fatal for the long term application of this alloy in the human body. To improve the long term biocompatibility and corrosion properties of NiTi, different surface treatment techniques have been investigated but no optimum technique has been established yet. This project will investigate the feasibility of applying laser surface alloying technique to improve the corrosion resistance and biocompatibility of NiTi in simulated body fluid condition. This thesis summarizes the result of laser surface modification of NiTi with Mo, Nb and Co using CO2 laser. The modified layer, which is free of microcracks and pores, acts as physical barrier to reduce nickel release and enhance the surface properties. The hardness values of the Mo-alloyed NiTi, Nb-alloyed NiTi and Co-alloyed NiTi surface were found to be three to four times harder than the NiTi substrate. Corrosion polarization tests also showed that the alloyed NiTi are significantly more resistant than the NiTi alloy. The release of Ni ions can be greatly reduced after laser surface alloying NiTi with Mo, Nb and Co. The improvement in wettability characteristics, the growth of the apatite on the specimen's surface and the adhesion of cell confirm the good biocompatibility after laser surface alloying. It is concluded that laser surface alloying is one of the potential technique not only to improve the corrosion resistance with low nickel release rate, but also retain the good

  7. Development of Advanced Surface Enhancement Technology for Decreasing Wear and Corrosion of Equipment Used for Mineral Processing

    Energy Technology Data Exchange (ETDEWEB)

    Daniel Tao; Craig A. Blue

    2006-07-20

    Equipment wear is a major concern in the mineral processing industry, which dramatically increases the maintenance cost and adversely affects plant operation efficiency. In this research, novel surface treatment technologies, High Density Infrared (HDI) and Laser Surface Engineering (LSE) surface coating processes were developed for the surface enhancement of selected mineral processing equipment. Microstructural and mechanical properties of the coated specimens were characterized. Laboratory-simulated wear tests were conducted to evaluate the tribological performance of the coated components. Test results indicate that the wear resistance of ASTM A36 (raw coal screen section) and can be significantly increased by applying HDI and LSE coating processes. Field testing has been performed using a LSE-treated screen panel and it showed a 2 times improvement of the service life.

  8. Development of Advanced Surface Enhancement Technology for Decreasing Wear and Corrosion of Equipment Used for Mineral Processing

    Energy Technology Data Exchange (ETDEWEB)

    Daniel Tao; Craig A. Blue

    2005-08-01

    Equipment wear is a major concern in the mineral processing industry, which dramatically increases the maintenance cost and adversely affects plant operation efficiency. In this research, a novel surface treatment technology, laser surface engineering (LSE) surface coating process was proposed for the surface enhancement of selected mineral processing equipment. Microstructural and mechanical properties of the coated specimen were characterized. Laboratory-simulated wear tests were conducted to evaluate the tribological performance of the coated components. Test results indicate that the wear resistance of ASTM A36 (raw coal screen section) and AISI 4140 steels can be increased 10 and 25 folds, respectively by the application of LSE process. Initial field testing showed a 2 times improvement of the service life of a raw coal screen panel.

  9. Development of Advanced Surface Enhancement Technology for Decreasing Wear and Corrosion of Equipment Used for Mineral Processing

    Energy Technology Data Exchange (ETDEWEB)

    Daniel Tao; R. Honaker; B. K. Parekh

    2007-09-20

    Equipment wear is a major concern in the mineral processing industry, which dramatically increases the maintenance cost and adversely affects plant operation efficiency. In this research, novel surface treatment technologies, High Density Infrared (HDI) and Laser Surface Engineering (LSE) surface coating processes were developed for the surface enhancement of selected mineral and coal processing equipment. Microstructural and mechanical properties of the coated specimens were characterized. Laboratory-simulated wear tests were conducted to evaluate the tribological performance of the coated components. Test results indicate that the wear resistance of ASTM A36 (raw coal screen section) and can be significantly increased by applying HDI and LSE coating processes. Field testing has been performed using a LSE-treated screen panel and it showed a significant improvement of the service life.

  10. Development of Advanced Surface Enhancement Technology for Decreasing Wear and Corrosion of Equipment Used for Mineral Processing

    Energy Technology Data Exchange (ETDEWEB)

    Daniel Tao; Craig A. Blue

    2004-08-01

    Equipment wear is a major concern in the mineral processing industry, which dramatically increases the maintenance cost and adversely affects plant operation efficiency. In this research, wear problems of mineral processing equipment including screens, sieve bends, heavy media vessel, dewatering centrifuge, etc., were identified. A novel surface treatment technology, high density infrared (HDI) surface coating process was proposed for the surface enhancement of selected mineral processing equipment. Microstructural and mechanical properties of the coated samples were characterized. Laboratory-simulated wear tests were conducted to evaluate the tribological performance of the coated components. Test results indicate that the wear resistance of AISI 4140 and ASTM A36 steels can be increased 3 and 5 folds, respectively by the application of HDI coatings.

  11. Advanced Surface Technology

    DEFF Research Database (Denmark)

    Møller, Per; Nielsen, Lars Pleht

    This new significant book on advanced modern surface technology in all its variations, is aimed at both teaching at engineering schools and practical application in industry. The work covers all the significant aspects of modern surface technology and also describes how new advanced techniques make......, nitriding, carbonitriding, and many other lesser-known thermochemical processes used for solving technological problems. The book is richly illustrated with pictures and figures showing how the technology creates new innovative solutions for industry and how surfaces are becoming integral to the function...

  12. Advanced Surface Technology

    DEFF Research Database (Denmark)

    Møller, Per; Nielsen, Lars Pleht

    it possible to examine surfaces all the way down to their atomic layers and also to perform realistic durability tests. The many surface techniques are described in clear and simple language, and the book is richly illustrated with detailed drawings and photos. It also deals with replacing environmentally......, nitriding, carbonitriding, and many other lesser-known thermochemical processes used for solving technological problems. The book is richly illustrated with pictures and figures showing how the technology creates new innovative solutions for industry and how surfaces are becoming integral to the function......This new significant book on advanced modern surface technology in all its variations, is aimed at both teaching at engineering schools and practical application in industry. The work covers all the significant aspects of modern surface technology and also describes how new advanced techniques make...

  13. Advanced Surface Technology

    DEFF Research Database (Denmark)

    Møller, Per; Nielsen, Lars Pleht

    of the components. It covers everything from biocompatible surfaces of IR absorbent or reflective surfaces to surfaces with specific properties within low friction, hardness, corrosion, colors, etc. The book includes more than 400 pages detailing virtually all analysis methods for examining at surfaces.......This new significant book on advanced modern surface technology in all its variations, is aimed at both teaching at engineering schools and practical application in industry. The work covers all the significant aspects of modern surface technology and also describes how new advanced techniques make...... it possible to examine surfaces all the way down to their atomic layers and also to perform realistic durability tests. The many surface techniques are described in clear and simple language, and the book is richly illustrated with detailed drawings and photos. It also deals with replacing environmentally...

  14. Surface enhanced Raman scattering

    CERN Document Server

    Furtak, Thomas

    1982-01-01

    In the course of the development of surface science, advances have been identified with the introduction of new diagnostic probes for analytical characterization of the adsorbates and microscopic structure of surfaces and interfaces. Among the most recently de­ veloped techniques, and one around which a storm of controversy has developed, is what has now been earmarked as surface enhanced Raman scattering (SERS). Within this phenomenon, molecules adsorbed onto metal surfaces under certain conditions exhibit an anomalously large interaction cross section for the Raman effect. This makes it possible to observe the detailed vibrational signature of the adsorbate in the ambient phase with an energy resolution much higher than that which is presently available in electron energy loss spectroscopy and when the surface is in contact with a much larger amount of material than that which can be tolerated in infrared absorption experiments. The ability to perform vibrational spectroscopy under these conditions would l...

  15. Surface enhanced thermo lithography

    KAUST Repository

    Coluccio, Maria Laura

    2017-01-13

    We used electroless deposition to fabricate clusters of silver nanoparticles (NPs) on a silicon substrate. These clusters are plasmonics devices that induce giant electromagnetic (EM) field increments. When those EM field are absorbed by the metal NPs clusters generate, in turn, severe temperature increases. Here, we used the laser radiation of a conventional Raman set-up to transfer geometrical patterns from a template of metal NPs clusters into a layer of thermo sensitive Polyphthalaldehyde (PPA) polymer. Temperature profile on the devices depends on specific arrangements of silver nanoparticles. In plane temperature variations may be controlled with (i) high nano-meter spatial precision and (ii) single Kelvin temperature resolution on varying the shape, size and spacing of metal nanostructures. This scheme can be used to generate strongly localized heat amplifications for applications in nanotechnology, surface enhanced thermo-lithography (SETL), biology and medicine (for space resolved cell ablation and treatment), nano-chemistry.

  16. Surface plasmon enhanced FRET

    Science.gov (United States)

    Steele, Jennifer M.; Ramnarace, Chae M.; Farner, William R.

    2017-08-01

    We demonstrate an increase in Förster Resonance Energy Transfer (FRET) efficiency for paired fluorescent molecules on gold nanogratings for a range of acceptor concentrations. For gratings, the periodicity allows for a broad range of surface plasmon wavelengths that follow a dispersion relationship. The dispersion relationship is determined by the periodicity of the grating and the dielectric function of the metal that makes the grating. Locating a fluorophore near a plasmonic metal structure increases the emission in two ways - an excitation enhancement and an emission modification. The second mechanism occurs when the plasmonic substrate increases the local density of optical states (LDOS). This has the effect of shortening the lifetime of the excited state which increases the quantum yield of the fluorophore. In this work, gold wire nanogratings with a period of 500 nm were fabricated. We used Atto 532 and Atto 633 as the donor and acceptor FRET molecules respectively. A thin layer of PVA containing different concentrations of the donor and acceptor FRET molecules was spun cast onto the gratings. The donor molecules were excited with a 532 nm laser, and the fluorescence emission from both the donor and acceptor molecules were recorded. We found that for all concentrations of acceptors, the FRET efficiency was the largest when the surface plasmon modes overlapped the acceptor emission. Compared to the unenhanced efficiency, the largest gains in efficiency were measured for the lowest concentration of acceptors.

  17. Technology Education Professional Enhancement Project

    Science.gov (United States)

    Hughes, Thomas A., Jr.

    1996-01-01

    The two goals of this project are: the use of integrative field of aerospace technology to enhance the content and instruction delivered by math, science, and technology teachers through the development of a new publication entitled NASA Technology Today, and to develop a rationale and structure for the study of technology, which establishes the foundation for developing technology education standards and programs of the future.

  18. Surface-Enhanced Raman Spectroscopy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 2. Surface-Enhanced Raman Spectroscopy - Recent Advancement of Raman Spectroscopy. Ujjal Kumar Sur. General Article Volume 15 Issue 2 February 2010 pp 154-164 ...

  19. Conformal adhesion enhancement on biomimetic microstructured surfaces.

    Science.gov (United States)

    Shahsavan, Hamed; Zhao, Boxin

    2011-06-21

    Inspired by the superior adhesive ability of the gecko foot pad, we report an experimental study of conformal adhesion of a soft elastomer thin film on biomimetic micropatterned surfaces (micropillars), showing a remarkable adhesion enhancement due to the surface patterning. The adhesion of a low-surface-energy poly(dimethylsiloxane) tape to a SU-8 micropatterned surface was found be able to increase by 550-fold as the aspect ratio increases from 0 to 6. The dependency of the adhesion enhancement on the aspect ratio is highly nonlinear. A series of peeling experiment coupled with optical interference imaging were performed to investigate the adhesion enhancement as a function of the height of the micropillars and the associated delamination mechanisms. Local elastic energy dissipation, side-wall friction, and plastic deformations were analyzed and discussed in terms of their contributions to the adhesion enhancement. We conclude that the local adhesion and friction events of pulling micropillars out of the embedded polymer film play a primary role in the observed adhesion enhancement. The technical implications of this local friction-based adhesion enhancement mechanism were discussed for the effective assembly of similar or dissimilar material components at small scales. The combined use of the micro/nanostructured surfaces with the van der Waals interactions seem to be a potentially more universal solution than the conventional adhesive bonding technology, which depends on the chemical and viscoelastic properties of the materials. © 2011 American Chemical Society

  20. Proceedings Technology Enhanced Assessment conference

    NARCIS (Netherlands)

    Joosten-ten Brinke, Desirée; Laanpere, Mart

    2018-01-01

    This book constitutes the proceedings of the 19th International Conference on Technology Enhanced Assessment, TEA 2016, held in Tallinn, Estonia, in October 2016. The 16 full papers presented were carefully selected from 38 submissions. They are centered around topics like measurement of higher

  1. Backscatter enhancement in scattering from rough surfaces

    Science.gov (United States)

    Papa, Robert J.; Woodworth, Margaret B.

    1989-06-01

    Stealth technology has advanced to the point where radar target cross sections are so small there is a great need to determine mean clutter cross sections and clutter variability with great accuracy. Established clutter prediction techniques result in forward scatter values that exceed backscatter. There is some new experimental data on light scattering from rough metallic surfaces which shows there is an enhancement of backscattering in the antispecular direction under some conditions. This unusual result has been addressed by several theoretical analyses with varying success at confirmation. In this report an integral form of a physical optics representation is used to simulate the experimental conditions. For a one-dimensional surface height variation this model predicts enhanced backscatter at optical frequencies. Additional calculations for the more significant radar case of microwave frequencies and a dielectric surface again predict an increase in backscatter for large or intermediate surface slope conditions.

  2. Enhancing cavitation with micromachined surfaces

    Science.gov (United States)

    Fernandez Rivas, David; Stricker, Laura; Zijlstra, Aaldert G.; Gardeniers, Han; Lohse, Detlef; Prosperetti, Andrea; Mesoscale Chemical System Group Collaboration; Physics of Fluids Group Collaboration; Department of Mechanical Engineering Collaboration

    2012-11-01

    When a silicon surface with micromachined pits submerged in a liquid is exposed to continuous ultrasound at 200 kHz, bubbles are ejected from the air filled cavities. Depending on the pressure amplitude different scenarios are observed, as the bubbles ejected from the micropits interact in complex ways with each other, and with the silicon surface. We have determined the size distribution of bubbles ejected from one, two and three pits for three different electrical power settings, and correlated them with sonochemical OH* radical production. Numerical simulations of the sonochemical conversion reaction rates were obtained using the empirical bubble size distributions and are compared with experimental results. Experimental evidence of shock wave emission from the microbubble clusters, deformed microbubble shapes, jetting and surface erosion are also presented. Financially supported through the project 07391 of the Technology Foundation STW, The Netherlands.

  3. Surface magnetic enhancement for coal cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, J.Y.

    1992-01-01

    The program consisted of a fundamental study to define the chemistry for the interactions between magnetic reagent and mineral and coal particles, a laboratory study to determine the applicability of this technology on coal cleaning, and a parameter study to evaluate the technical and economical feasibility of this technology for desulfurization and de-ashing under various processing schemes. Surface magnetic enhancement using magnetic reagent is a new technology developed at the Institute. This technology can be applied to separate pyrite and other minerals particles from coal with a magnetic separation after adsorbing magnetic reagent on the surface of pyrite and other minerals particles. Particles which have absorbed magnetic reagent are rendered magnetic. The adsorption can be controlled to yield selectivity. Thus, the separation of traditionally nonmagnetic materials with a magnetic separator can be achieved. Experiments have been performed to demonstrate the theoretical fundamentals and the applications of the technology. Adsorbability, adsorption mechanisms, and adsorption selectivity are included in the fundamental study. The effects of particle size, magnetic reagent dosage, solid contents, magnetic matrix, applied magnetic field strengths, retention times, and feed loading capacities are included in the application studies. Three coals, including Illinois No. 6, Lower Kittanning and Pocahontas seams, have been investigated. More than 90% pyritic sulfur and ash reductions have been achieved. Technical and economic feasibilities of this technology have been demonstrated in this study. Both are competitive to that of the froth flotation approach for coal cleaning.

  4. Complementary surface charge for enhanced capacitive deionization

    NARCIS (Netherlands)

    Gao, X.; Porada, S.; Omosebi, A.; Liu, K.L.; Biesheuvel, P.M.; Landon, J.

    2016-01-01

    Commercially available activated carbon cloth electrodes are treated using nitric acid and ethylenediamine solutions, resulting in chemical surface charge enhanced carbon electrodes for capacitive deionization (CDI) applications. Surface charge enhanced electrodes are then configured in a CDI

  5. Energy conservation potential of surface modification technologies

    Energy Technology Data Exchange (ETDEWEB)

    Le, H.K.; Horne, D.M.; Silberglitt, R.S.

    1985-09-01

    This report assesses the energy conservation impact of surface modification technologies on the metalworking industries. The energy conservation impact of surface modification technologies on the metalworking industries is assessed by estimating their friction and wear tribological sinks and the subsequent reduction in these sinks when surface modified tools are used. Ion implantation, coatings, and laser and electron beam surface modifications are considered.

  6. An Evaluation of Enhanced Geothermal Systems Technology

    Energy Technology Data Exchange (ETDEWEB)

    Jelacic, Allan [U.S. Dept. of Energy, Washington, DC (United States); Fortuna, Raymond [U.S. Dept. of Energy, Washington, DC (United States); LaSala, Raymond [U.S. Dept. of Energy, Washington, DC (United States); Nathwani, Jay [U.S. Dept. of Energy, Washington, DC (United States); Nix, Gerald [U.S. Dept. of Energy, Washington, DC (United States); Visser, Charles [National Renewable Energy Lab. (NREL), Golden, CO (United States); Green, Bruce [National Renewable Energy Lab. (NREL), Golden, CO (United States); Renner, Joel [Idaho National Lab. (INL), Idaho Falls, ID (United States); Blankenship, Douglas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kennedy, Mack [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bruton, Carol [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2008-04-01

    This 2008 document presents the results of an eight-month study by the Department of Energy (DOE) and its support staff at the national laboratories concerning the technological requirements to commercialize a new geothermal technology, Enhanced Geothermal Systems (EGS).

  7. Recommender Systems in Technology Enhanced Learning

    NARCIS (Netherlands)

    Manouselis, Nikos; Drachsler, Hendrik; Verbert, Katrien; Santos, Olga

    2010-01-01

    Manouselis, N., Drachsler, H., Verbert, K., & Santos, C. S. (Eds.) (2010). Recommender System in Technology Enhanced Learning. Elsevier Procedia Computer Science: Volume 1, Issue 2. Proceedings of the 1st Workshop on Recommender Systems for Technology Enhanced Learning (RecSysTEL). September, 29-30,

  8. Nanoparticle Based Surface-Enhanced Raman Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Talley, C E; Huser, T R; Hollars, C W; Jusinski, L; Laurence, T; Lane, S M

    2005-01-03

    Surface-enhanced Raman scattering is a powerful tool for the investigation of biological samples. Following a brief introduction to Raman and surface-enhanced Raman scattering, several examples of biophotonic applications of SERS are discussed. The concept of nanoparticle based sensors using SERS is introduced and the development of these sensors is discussed.

  9. Recommender Systems in Technology Enhanced Learning

    NARCIS (Netherlands)

    Manouselis, Nikos; Drachsler, Hendrik; Vuorikari, Riina; Hummel, Hans; Koper, Rob

    2010-01-01

    Manouselis, N., Drachsler, H., Vuorikari, R., Hummel, H. G. K., & Koper, R. (2011). Recommender Systems in Technology Enhanced Learning. In P. B. Kantor, F. Ricci, L. Rokach, & B. Shapira (Eds.), Recommender Systems Handbook (pp. 387-415). Berlin: Springer.

  10. Learning in a technology enhanced world

    NARCIS (Netherlands)

    Specht, Marcus

    2010-01-01

    Specht, M. (2009). Learning in a technology enhanced world. Invited talk given at the World Conference on E-learning in Corporate, Government, Healthcare & Higher Education. October, 27, 2009, Vancouver, Canada.

  11. Teacher Design Knowledge for Technology Enhanced Learning

    NARCIS (Netherlands)

    McKenney, Susan

    2014-01-01

    This presentation shares a framework for investigating the knowledge teachers need to be able to design technology-enhanced learning. Specific activities are undertaken to consider elements within the framework

  12. Technology Enhanced Learning: Best Practices

    Science.gov (United States)

    Lytras, Miltiadis D., Ed.; Gasevic, Dragan, Ed.; Ordonez de Pablos, Patricia, Ed.; Huang, Weihong, Ed.

    2008-01-01

    With the shift towards the knowledge society, the change of working conditions, and the high-speed evolution of information and communication technologies, peoples' knowledge and skills need continuous updating. Learning based on collaborative working, creativity, multidisciplinarity, adaptiveness, intercultural communication, and problem solving…

  13. Surface mount technology terms and concepts

    CERN Document Server

    Zarrow, Phil

    1997-01-01

    In today's fast-paced world of technology, keeping up with new terms and concepts can be quite a challenge. Surface Mount Technology Terms and Concepts is an invaluable reference containing over 1000 terms and definitions used in the SMT field. Each term is followed by a paragraph or two explaining the meaning and how it fits into the surface mount industry. The easy lookup and concise explanations make it ideal for those starting out in the field as well as professionals already involved in surface mount design and assembly.Glossary of over 1000 surface mount technology terms

  14. Enhanced living environments from models to technologies

    CERN Document Server

    Dobre, Ciprian; Ganchev, Ivan; Garcia, Nuno; Goleva, Rossitza Ivanova

    2017-01-01

    Enhanced living environments employ information and communications technologies to support true ambient assisted living for people with disabilities. This book provides an overview of today's architectures, techniques, protocols, components, and cloud-based solutions related to ambient assisted living and enhanced living environments.

  15. Enhancing Fieldwork Learning with Technology: Practitioner's Perspectives

    Science.gov (United States)

    Welsh, Katharine E.; Mauchline, Alice L.; Park, Julian R.; Whalley, W. Brian; France, Derek

    2013-01-01

    This research paper reports the findings from an international survey of fieldwork practitioners on their use of technology to enhance fieldwork teaching and learning. It was found that there was high information technology usage before and after time in the field, but some were also using portable devices such as smartphones and global…

  16. Chiral Surface Waves for Enhanced Circular Dichroism

    CERN Document Server

    Pellegrini, Giovanni; Celebrano, Michele; Duò, Lamberto; Biagioni, Paolo

    2016-01-01

    We present a novel chiral sensing platform that combines a one-dimensional photonic crystal design with a birefringent surface defect. The platform sustains simultaneous transverse electric and transverse magnetic surface modes, which are exploited to generate chiral surface waves. The present design provides homogeneous and superchiral fields of both handednesses over arbitrarily large areas in a wide spectral range, resulting in the enhancement of the circular dichroism signal by two orders of magnitude, thus paving the road toward the successful combination of surface-enhanced spectroscopies and electromagnetic superchirality.

  17. Microscale surface modifications for heat transfer enhancement.

    Science.gov (United States)

    Bostanci, Huseyin; Singh, Virendra; Kizito, John P; Rini, Daniel P; Seal, Sudipta; Chow, Louis C

    2013-10-09

    In this experimental study, two surface modification techniques were investigated for their effect on heat transfer enhancement. One of the methods employed the particle (grit) blasting to create microscale indentations, while the other used plasma spray coating to create microscale protrusions on Al 6061 (aluminum alloy 6061) samples. The test surfaces were characterized using scanning electron microscopy (SEM) and confocal scanning laser microscopy. Because of the surface modifications, the actual surface area was increased up to 2.8× compared to the projected base area, and the arithmetic mean roughness value (Ra) was determined to vary from 0.3 μm for the reference smooth surface to 19.5 μm for the modified surfaces. Selected samples with modified surfaces along with the reference smooth surface were then evaluated for their heat transfer performance in spray cooling tests. The cooling system had vapor-atomizing nozzles and used anhydrous ammonia as the coolant in order to achieve heat fluxes up to 500 W/cm(2) representing a thermal management setting for high power systems. Experimental results showed that the microscale surface modifications enhanced heat transfer coefficients up to 76% at 500 W/cm(2) compared to the smooth surface and demonstrated the benefits of these practical surface modification techniques to enhance two-phase heat transfer process.

  18. Surface-enhanced Raman spectroscopy: nonlocal limitations

    DEFF Research Database (Denmark)

    Toscano, Giuseppe; Raza, Søren; Xiao, Sanshui

    2012-01-01

    for our understanding of surface-enhanced Raman spectroscopy (SERS). The intrinsic length scale of the electron gas serves to smear out assumed field singularities, leaving the SERS enhancement factor finite, even for geometries with infinitely sharp features. For silver nanogroove structures, mimicked...

  19. Fission Surface Power Technology Development Status

    Science.gov (United States)

    Palac, Donald T.; Mason, Lee S.; Houts, Michael G.; Harlow, Scott

    2010-01-01

    Power is a critical consideration in planning exploration of the surfaces of the Moon, Mars, and beyond. Nuclear power is an important option, especially for locations in the solar system where sunlight is limited in availability or intensity. NASA is maintaining the option for fission surface power for the Moon and Mars by developing and demonstrating technology for an affordable fission surface power system. Because affordability drove the determination of the system concept that this technology will make possible, low development and recurring costs result, while required safety standards are maintained. However, an affordable approach to fission surface power also provides the benefits of simplicity, robustness, and conservatism in design. This paper will illuminate the multiplicity of benefits to an affordable approach to fission surface power, and will describe how the foundation for these benefits is being developed and demonstrated in the Exploration Technology Development Program s Fission Surface Power Project.

  20. Technology-enhanced human interaction in psychotherapy.

    Science.gov (United States)

    Imel, Zac E; Caperton, Derek D; Tanana, Michael; Atkins, David C

    2017-07-01

    Psychotherapy is on the verge of a technology-inspired revolution. The concurrent maturation of communication, signal processing, and machine learning technologies begs an earnest look at how these technologies may be used to improve the quality of psychotherapy. Here, we discuss 3 research domains where technology is likely to have a significant impact: (1) mechanism and process, (2) training and feedback, and (3) technology-mediated treatment modalities. For each domain, we describe current and forthcoming examples of how new technologies may change established applications. Moreover, for each domain we present research questions that touch on theoretical, systemic, and implementation issues. Ultimately, psychotherapy is a decidedly human endeavor, and thus the application of modern technology to therapy must capitalize on-and enhance-our human capacities as counselors, students, and supervisors. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  1. Policy implications of technologies for cognitive enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Sarewitz, Daniel R. (Arizona State University, Tempe, AZ); Karas, Thomas H.

    2007-02-01

    The Advanced Concepts Group at Sandia National Laboratory and the Consortium for Science, Policy and Outcomes at Arizona State University convened a workshop in May 2006 to explore the potential policy implications of technologies that might enhance human cognitive abilities. The group's deliberations sought to identify core values and concerns raised by the prospect of cognitive enhancement. The workshop focused on the policy implications of various prospective cognitive enhancements and on the technologies/nanotechnology, biotechnology, information technology, and cognitive science--that enable them. The prospect of rapidly emerging technological capabilities to enhance human cognition makes urgent a daunting array of questions, tensions, ambitions, and concerns. The workshop elicited dilemmas and concerns in ten overlapping areas: science and democracy; equity and justice; freedom and control; intergenerational issues; ethics and competition; individual and community rights; speed and deliberations; ethical uncertainty; humanness; and sociocultural risk. We identified four different perspectives to encompass the diverse issues related to emergence of cognitive enhancement technologies: (1) Laissez-faire--emphasizes freedom of individuals to seek and employ enhancement technologies based on their own judgment; (2) Managed technological optimism--believes that while these technologies promise great benefits, such benefits cannot emerge without an active government role; (3) Managed technological skepticism--views that the quality of life arises more out of society's institutions than its technologies; and (4) Human Essentialism--starts with the notion of a human essence (whether God-given or evolutionary in origin) that should not be modified. While the perspectives differ significantly about both human nature and the role of government, each encompasses a belief in the value of transparency and reliable information that can allow public discussion and

  2. Technologies and countermeasures for gas recovery enhancement

    Directory of Open Access Journals (Sweden)

    Guo Ping

    2014-10-01

    Full Text Available Since 2000, China has been ranked as one of the top countries in gas production. Nevertheless, the domestic gas production can hardly satisfy the need of national economic development. Besides, an increasing number of gas fields have come to the middle or late development stages, and most gas reservoirs have low recovery efficiency due to the low permeability and water drive nature. Therefore, gas recovery enhancement has become an urgent issue. At present, the oil recovery enhancement is well defined, and there are methods describing the remaining oil and a complete set of mature EOR (enhanced oil recovery technologies. However, the definition and description of EGR (enhanced gas recovery are still undermined, and the description method for the distribution of residual gas and EGR technologies are almost unavailable. In view of this, by reviewing a wealth of related literatures, we defined EGR and also described the remaining gas distribution based on the remaining gas abundance. In addition, collecting three typical types (low-permeability, condensate and edge/bottom water of major gas reservoirs developed both at home and abroad, we summarized the geological and development characteristics, and found out the obstructions in the development. In response, we concluded and analyzed the relevant technologies and methods for enhancing the gas recovery of such reservoirs, and proposed the suggestions about EGR technology development, which provides a significant reference and popularization basis for EGR measures in fields.

  3. Computational intelligence for technology enhanced learning

    Energy Technology Data Exchange (ETDEWEB)

    Xhafa, Fatos [Polytechnic Univ. of Catalonia, Barcelona (Spain). Dept. of Languages and Informatics Systems; Caballe, Santi; Daradoumis, Thanasis [Open Univ. of Catalonia, Barcelona (Spain). Dept. of Computer Sciences Multimedia and Telecommunications; Abraham, Ajith [Machine Intelligence Research Labs (MIR Labs), Auburn, WA (United States). Scientific Network for Innovation and Research Excellence; Juan Perez, Angel Alejandro (eds.) [Open Univ. of Catalonia, Barcelona (Spain). Dept. of Information Sciences

    2010-07-01

    E-Learning has become one of the most wide spread ways of distance teaching and learning. Technologies such as Web, Grid, and Mobile and Wireless networks are pushing teaching and learning communities to find new and intelligent ways of using these technologies to enhance teaching and learning activities. Indeed, these new technologies can play an important role in increasing the support to teachers and learners, to shorten the time to learning and teaching; yet, it is necessary to use intelligent techniques to take advantage of these new technologies to achieve the desired support to teachers and learners and enhance learners' performance in distributed learning environments. The chapters of this volume bring advances in using intelligent techniques for technology enhanced learning as well as development of e-Learning applications based on such techniques and supported by technology. Such intelligent techniques include clustering and classification for personalization of learning, intelligent context-aware techniques, adaptive learning, data mining techniques and ontologies in e-Learning systems, among others. Academics, scientists, software developers, teachers and tutors and students interested in e-Learning will find this book useful for their academic, research and practice activity. (orig.)

  4. Teachers as designers of technology enhanced learning

    NARCIS (Netherlands)

    Kali, Yael; McKenney, Susan; Sagy, Ornit; Voogt, Joke

    2015-01-01

    Design of (technology-enhanced) learning activities and materials is one fruitful process through which teachers learn and become professionals. To facilitate this process, research is needed to understand how teachers learn through design, how this process may be supported, and how teacher

  5. Surface enhanced raman spectroscopy on chip

    DEFF Research Database (Denmark)

    Hübner, Jörg; Anhøj, Thomas Aarøe; Zauner, Dan

    2007-01-01

    In this paper we report low resolution surface enhanced Raman spectra (SERS) conducted with a chip based spectrometer. The flat field spectrometer presented here is fabricated in SU-8 on silicon, showing a resolution of around 3 nm and a free spectral range of around 100 nm. The output facet...... fiber. The obtained spectra show that chip based spectrometer together with the SERS active surface can be used as Raman sensor....

  6. Lunar Surface Systems Supportability Technology Development Roadmap

    Science.gov (United States)

    Oeftering, Richard C.; Struk, Peter M.; Green, Jennifer L.; Chau, Savio N.; Curell, Philip C.; Dempsey, Cathy A.; Patterson, Linda P.; Robbins, William; Steele, Michael A.; DAnnunzio, Anthony; hide

    2011-01-01

    The Lunar Surface Systems Supportability Technology Development Roadmap is a guide for developing the technologies needed to enable the supportable, sustainable, and affordable exploration of the Moon and other destinations beyond Earth. Supportability is defined in terms of space maintenance, repair, and related logistics. This report considers the supportability lessons learned from NASA and the Department of Defense. Lunar Outpost supportability needs are summarized, and a supportability technology strategy is established to make the transition from high logistics dependence to logistics independence. This strategy will enable flight crews to act effectively to respond to problems and exploit opportunities in an environment of extreme resource scarcity and isolation. The supportability roadmap defines the general technology selection criteria. Technologies are organized into three categories: diagnostics, test, and verification; maintenance and repair; and scavenge and recycle. Furthermore, "embedded technologies" and "process technologies" are used to designate distinct technology types with different development cycles. The roadmap examines the current technology readiness level and lays out a four-phase incremental development schedule with selection decision gates. The supportability technology roadmap is intended to develop technologies with the widest possible capability and utility while minimizing the impact on crew time and training and remaining within the time and cost constraints of the program.

  7. Fission Surface Power Technology Development Update

    Science.gov (United States)

    Palac, Donald T.; Mason, Lee S.; Houts, Michael G.; Harlow, Scott

    2011-01-01

    Power is a critical consideration in planning exploration of the surfaces of the Moon, Mars, and places beyond. Nuclear power is an important option, especially for locations in the solar system where sunlight is limited or environmental conditions are challenging (e.g., extreme cold, dust storms). NASA and the Department of Energy are maintaining the option for fission surface power for the Moon and Mars by developing and demonstrating technology for a fission surface power system. The Fission Surface Power Systems project has focused on subscale component and subsystem demonstrations to address the feasibility of a low-risk, low-cost approach to space nuclear power for surface missions. Laboratory demonstrations of the liquid metal pump, reactor control drum drive, power conversion, heat rejection, and power management and distribution technologies have validated that the fundamental characteristics and performance of these components and subsystems are consistent with a Fission Surface Power preliminary reference concept. In addition, subscale versions of a non-nuclear reactor simulator, using electric resistance heating in place of the reactor fuel, have been built and operated with liquid metal sodium-potassium and helium/xenon gas heat transfer loops, demonstrating the viability of establishing system-level performance and characteristics of fission surface power technologies without requiring a nuclear reactor. While some component and subsystem testing will continue through 2011 and beyond, the results to date provide sufficient confidence to proceed with system level technology readiness demonstration. To demonstrate the system level readiness of fission surface power in an operationally relevant environment (the primary goal of the Fission Surface Power Systems project), a full scale, 1/4 power Technology Demonstration Unit (TDU) is under development. The TDU will consist of a non-nuclear reactor simulator, a sodium-potassium heat transfer loop, a power

  8. Intuitive information technology: enhancing clinician efficiency.

    Science.gov (United States)

    Procuniar, Molly; Murphy, Sue

    2008-11-06

    Although medical technology is making great strides in improved diagnosis and treatment, the technologies used to document, communicate, and manage those activities are limiting its progress by converting clinicians into computer operators. In an environment of nurse and doctor shortages, reducing their efficiency is counter productive. Technology in healthcare that does not serve patients by improving cost, quality, or care delivery is technology that serves no purpose. Requiring clinicians to chart away from the bedside using technologies that do not feel intuitive, such as keyboarding and mouse use reduces efficiency of workflow, impedes direct care, and increases the cost of training. Intuitive forms of technology such as surface technology, voice activated charting, or digital pens, if embraced, could cause significant changes in healthcare workflows. Clinicians could be more focused on direct care and less utilized in clerical activity. The time it takes to access information could be decreased exponentially--and the opportunities to interact with that information would present a nearly endless horizon. This impact would be especially crucial in high acuity areas and emergency patient care situations. In short, technology should embrace familiar, natural movements and develop intuitive interfaces to improve effectiveness in the healthcare market of the future.

  9. The Technology Enhanced Conference - A Board Game!

    DEFF Research Database (Denmark)

    Pedersen, Annette

    aid: turning it into a board game simply called The Conference Game. By making a children's board game, we let organizers play around with the options, get an overview – and the game element makes it just a little bit less dangerous, and more fun to play around with new technologies. Reception has...... been great, and maybe the board game can be used for other areas, where one needs to communicate complicated options for technology enhanced events or teaching and support organizers in making good choices....

  10. Surface Plasmon-Coupled Enhanced Transmission

    CERN Document Server

    Djalalian-Assl, Amir

    2016-01-01

    Investigations show a strong coupling between a dipole and the surface wave occurs when a dipole is positioned within 10 nm from a metallic surface. This is in contrast to what was thought previously with surface plasmon-coupled emission where the emission of a dipole was claimed to be quenched when positioned within 10 nm from a metallic surface. In fact, the quenching distance is related to the energy transfer between the dipole that acts as a donor and the metallic surface acting as an acceptor. For distances less 10 nm away from a flat metallic surface a total energy transfer occurs, producing evanescent surface waves that are plasmonic in nature. When investigating a metallic nanohole on an optically dense substrate (such as diamond with NV-), the scattering occured preferentially from the diamond substrate towards the air for dipole distances less 10 nm from the aperture. In addition, an enhancement to the dipole's radiative decay rate was observed. The relationship between an emitter and a nearby reson...

  11. Surface Structure Enhanced Microchannel Flow Boiling

    OpenAIRE

    Zhu, Yangying; Antao, Dion Savio; Chu, Kuang-Han; Chen, Siyu; Hendricks, Terry J.; Zhang, Tiejun; Wang, Evelyn N.

    2016-01-01

    We investigated the role of surface microstructures in two-phase microchannels on suppressing flow instabilities and enhancing heat transfer. We designed and fabricated microchannels with well-defined silicon micropillar arrays on the bottom heated microchannel wall to promote capillary flow for thin film evaporation while facilitating nucleation only from the sidewalls. Our experimental results show significantly reduced temperature and pressure drop fluctuation especially at high heat fluxe...

  12. Enhanced Propagating Surface Plasmon Signal Detection

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Yu; Joly, Alan G.; El-Khoury, Patrick Z.; Hess, Wayne P.

    2016-12-21

    Overcoming the dissipative nature of propagating surface plasmons (PSPs) is pre-requisite to realizing functional plasmonic circuitry, in which large bandwidth signals can be manipulated over length scales far-below the diffraction limit of light. To this end, we report on a novel PSP enhanced signal detection technique achieved in an all-metallic substrate. We take advantage of two strategically spatio-temporally separated phase-locked femtosecond laser pulses, incident onto lithographically patterned PSP coupling structures. We follow PSP propagation with joint femtosecond temporal and nanometer spatial resolution in a time-resolved non-linear photoemission electron microscopy scheme. Initially, a PSP signal wave packet is launched from a hole etched into the silver surface from where it propagates through an open trench structure and is decoded through the use of a timed probe pulse. FDTD calculations demonstrate that PSP signal waves may traverse open trenches in excess of 10 microns in diameter, thereby allowing remote detection even through vacuum regions. This arrangement results in a 10X enhancement in photoemission relative to readout from the bare metal surface. The enhancement is attributed to an all-optical homodyne detection technique that mixes signal and reference PSP waves in a non-linear scheme. Larger readout trenches achieve higher readout levels, however reduced transmission through the trench limits the trench size to 6 microns for maximum readout levels. However, the use of an array of trenches increases the maximum enhancement to near 30X. The attainable enhancement factor may be harnessed to achieve extended coherent PSP propagation in ultrafast plasmonic circuitry.

  13. AFCI Safeguards Enhancement Study: Technology Development Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Leon E.; Dougan, A.; Tobin, Stephen; Cipiti, B.; Ehinger, Michael H.; Bakel, A. J.; Bean, Robert; Grate, Jay W.; Santi, P.; Bryan, Steven; Kinlaw, M. T.; Schwantes, Jon M.; Burr, Tom; Lehn, Scott A.; Tolk, K.; Chichester, David; Menlove, H.; Vo, D.; Duckworth, Douglas C.; Merkle, P.; Wang, T. F.; Duran, F.; Nakae, L.; Warren, Glen A.; Friedrich, S.; Rabin, M.

    2008-12-31

    The Advanced Fuel Cycle Initiative (AFCI) Safeguards Campaign aims to develop safeguards technologies and processes that will significantly reduce the risk of proliferation in the U.S. nuclear fuel cycle of tomorrow. The Safeguards Enhancement Study was chartered with identifying promising research and development (R&D) directions over timescales both near-term and long-term, and under safeguards oversight both domestic and international. This technology development roadmap documents recognized gaps and needs in the safeguarding of nuclear fuel cycles, and outlines corresponding performance targets for each of those needs. Drawing on the collective expertise of technologists and user-representatives, a list of over 30 technologies that have the potential to meet those needs was developed, along with brief summaries of each candidate technology. Each summary describes the potential impact of that technology, key research questions to be addressed, and prospective development milestones that could lead to a definitive viability or performance assessment. Important programmatic linkages between U.S. agencies and offices are also described, reflecting the emergence of several safeguards R&D programs in the U.S. and the reinvigoration of nuclear fuel cycles across the globe.

  14. Surface magnetic enhancement for coal cleaning. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, J.Y.

    1992-10-01

    The program consisted of a fundamental study to define the chemistry for the interactions between magnetic reagent and mineral and coal particles, a laboratory study to determine the applicability of this technology on coal cleaning, and a parameter study to evaluate the technical and economical feasibility of this technology for desulfurization and de-ashing under various processing schemes. Surface magnetic enhancement using magnetic reagent is a new technology developed at the Institute. This technology can be applied to separate pyrite and other minerals particles from coal with a magnetic separation after adsorbing magnetic reagent on the surface of pyrite and other minerals particles. Particles which have absorbed magnetic reagent are rendered magnetic. The adsorption can be controlled to yield selectivity. Thus, the separation of traditionally nonmagnetic materials with a magnetic separator can be achieved. Experiments have been performed to demonstrate the theoretical fundamentals and the applications of the technology. Adsorbability, adsorption mechanisms, and adsorption selectivity are included in the fundamental study. The effects of particle size, magnetic reagent dosage, solid contents, magnetic matrix, applied magnetic field strengths, retention times, and feed loading capacities are included in the application studies. Three coals, including Illinois No. 6, Lower Kittanning and Pocahontas seams, have been investigated. More than 90% pyritic sulfur and ash reductions have been achieved. Technical and economic feasibilities of this technology have been demonstrated in this study. Both are competitive to that of the froth flotation approach for coal cleaning.

  15. Enhanced Attenuation Technologies: Passive Soil Vapor Extraction

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K.; Looney, B.; Kamath, R.; Adamson, D.; Newell, C.

    2010-03-15

    Passive soil vapor extraction (PSVE) is an enhanced attenuation (EA) approach that removes volatile contaminants from soil. The extraction is driven by natural pressure gradients between the subsurface and atmosphere (Barometric Pumping), or by renewable sources of energy such as wind or solar power (Assisted PSVE). The technology is applicable for remediating sites with low levels of contamination and for transitioning sites from active source technologies such as active soil vapor extraction (ASVE) to natural attenuation. PSVE systems are simple to design and operate and are more cost effective than active systems in many scenarios. Thus, PSVE is often appropriate as an interim-remedial or polishing strategy. Over the past decade, PSVE has been demonstrated in the U.S. and in Europe. These demonstrations provide practical information to assist in selecting, designing and implementing the technology. These demonstrations indicate that the technology can be effective in achieving remedial objectives in a timely fashion. The keys to success include: (1) Application at sites where the residual source quantities, and associated fluxes to groundwater, are relatively low; (2) Selection of the appropriate passive energy source - barometric pumping in cases with a deep vadose zone and barrier (e.g., clay) layers that separate the subsurface from the atmosphere and renewable energy assisted PSVE in other settings and where higher flow rates are required. (3) Provision of sufficient access to the contaminated vadose zones through the spacing and number of extraction wells. This PSVE technology report provides a summary of the relevant technical background, real-world case study performance, key design and cost considerations, and a scenario-based cost evaluation. The key design and cost considerations are organized into a flowchart that dovetails with the Enhanced Attenuation: Chlorinated Organics Guidance of the Interstate Technology and Regulatory Council (ITRC). The PSVE

  16. PRODUCTION WELL PERFORMANCE ENHANCEMENT USING SONICATION TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Michael A. Adewumi; M. Thaddeus Ityokumbul; Robert W. Watson; Mario Farias; Glenn Heckman; Johnson Olanrewaju; Eltohami Eltohami; Bruce G. Miller; W. Jack Hughes; Thomas C. Montgomery

    2003-12-17

    The objective of this project is to develop a sonic well performance enhancement technology that focuses on near wellbore formations. In order to successfully achieve this objective, a three-year project has been defined with each year consisting of four tasks. The first task is the laboratory-scale study whose goal is to determine the underlying principles of the technology. The second task will develop a scale-up mathematical model to serve as the design guide for tool development. The third task is to develop effective transducers that can operate with variable frequency so that the most effective frequencies can be applied in any given situation. The system, assembled as part of the production string, ensures delivery of sufficient sonic energy to penetrate the near-wellbore formation. The last task is the actual field testing of the tool. The first year of the project has been completed.

  17. Solar technology application to enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    de Leon, P.; Brown, K.C.; Margolis, J.W.; Nasr, L.H.

    1979-12-01

    One proposed near-term commercial application for solar energy technology is the use of solar energy systems to generate steam for thermal enhanced oil recovery (EOR). This report examines four aspects of solar energy employed for steam EOR. First, six solar technologies are evaluated and two - parabolic troughs and central receivers - are selected for closer study; typical systems that would meet current production requirements are proposed and costed. Second, the legal and environmental issues attending solar EOR are analyzed. Third, the petroleum producing companies' preferences and requirements are discussed. Finally, alternative means of financing solar EOR are addressed. The study concludes that within the next four to five years, conventional (fossil-fueled) thermal EOR means are much less expensive and more available than solar EOR systems, even given environmental requirements. Within 10 to 15 years, assuming specified advances in solar technologies, central receiver EOR systems will be significantly more cost-effective than parabolic trough EOR systems and will be price competitive with conventional thermal EOR systems. Important uncertainties remain (both in solar energy technologies and in how they affect the operating characteristics of petroleum reservoirs) that need resolution before definitive projections can be made.

  18. Anisotropic impedance surfaces for enhanced antenna isolation

    Science.gov (United States)

    Miragliotta, Joseph A.; Shrekenhamer, David; Sievenpiper, Daniel F.

    2015-09-01

    Anisotropic impedance surfaces, which include metasurfaces and high impedance surfaces (HIS), can be designed to control the amplitude and propagation direction of surface electromagnetic waves and are an effective means to enhance the isolation between antennas that share a common ground plane. To date, the majority of metastructures that have been designed for antenna isolation have relied on an isotropic distribution of unit cells that possess a stop band that inhibits the propagation of surface waves between neighboring antennas. A less common approach to isolation has been through the design of a metasurface that enables the re-direction of surface waves away from the location of the antenna structure, which effectively limits the coupling. In this paper, we discuss results from our computational investigation associated with improving antenna isolation through the use of an anisotropic metastructure. Simulated results associated with the isolation performance of two simple, but similar, anisotropic structures are compared to the corresponding results from a broadband magnetic radar absorbing materials (magRAM).

  19. Imaging of surfaces by concurrent surface plasmon resonance and surface plasmon resonance-enhanced fluorescence.

    Directory of Open Access Journals (Sweden)

    Rahber Thariani

    Full Text Available Surface plasmon resonance imaging and surface plasmon induced fluorescent are sensitive tools for surface analysis. However, existing instruments in this area have provided limited capability for concurrent detection, and may be large and expensive. We demonstrate a highly cost-effective system capable of concurrent surface plasmon resonance microscopy (SPRM and surface plasmon resonance-enhanced fluorescence (SPRF imaging, allowing for simultaneous monitoring of reflectivity and fluorescence from discrete spatial regions. The instrument allows for high performance imaging and quantitative measurements with surface plasmon resonance, and surface plasmon induced fluorescence, with inexpensive off-the-shelf components.

  20. Volume and Surface-Enhanced Volume Negative Ion Sources

    CERN Document Server

    Stockli, M.P.

    2013-12-16

    H- volume sources and, especially, caesiated H- volume sources are important ion sources for generating high-intensity proton beams, which then in turn generate large quantities of other particles. This chapter discusses the physics and technology of the volume production and the caesium-enhanced (surface) production of H- ions. Starting with Bacal's discovery of the H- volume production, the chapter briefly recounts the development of some H- sources, which capitalized on this process to significantly increase the production of H- beams. Another significant increase was achieved in the 1990s by adding caesiated surfaces to supplement the volume-produced ions with surface-produced ions, as illustrated with other H- sources. Finally, the focus turns to some of the experience gained when such a source was successfully ramped up in H- output and in duty factor to support the generation of 1 MW proton beams for the Spallation Neutron Source.

  1. Electric field enhanced dropwise condensation on hydrophobic surfaces

    Science.gov (United States)

    Baratian, Davood; Hoek, Harmen; van den Ende, Dirk; Mugele, Frieder; Physics of Complex Fluids Team

    2016-11-01

    Dropwise condensation occurs when vapor condenses on a low surface energy surface, and the substrate is just partially wetted by the condensate. Dropwise condensation has attracted significant attention due to its reported superior heat transfer performance compared to filmwise condensation. Extensive research efforts are focused on how to promote, and enhance dropwise condensation by considering both physical and chemical factors. We have studied electrowetting-actuated condensation on hydrophobic surfaces, aiming for enhancement of heat transfer in dropwise condensation. The idea is to use suitably structured patterns of micro-electrodes that generate a heterogeneous electric field at the interface and thereby promote both the condensation itself and the shedding of condensed drops. Comforting the shedding of droplets on electrowetting-functionalized surfaces allows more condensing surface area for re-nucleation of small droplets, leading to higher condensation rates. Possible applications of this innovative concept include heat pipes for (micro) coolers in electronics as well as in more efficient heat exchangers. We acknowledge financial support by the Dutch Technology Foundation STW, which is part of the Netherlands Organization for Scientific Research (NWO), within the VICI program.

  2. Nanopillars array for surface enhanced Raman scattering

    Energy Technology Data Exchange (ETDEWEB)

    S.P. Chang, A; Bora, M; Nguyen, H T; Behymer, E M; Larson, C C; Britten, J A; Carter, J C; Bond, T C

    2011-04-14

    The authors present a new class of surface-enhanced Raman scattering (SERS) substrates based on lithographically-defined two-dimensional rectangular array of nanopillars. Two types of nanopillars within this class are discussed: vertical pillars and tapered pillars. For the vertical pillars, the gap between each pair of nanopillars is small enough (< 50 nm) such that highly confined plasmonic cavity resonances are supported between the pillars when light is incident upon them, and the anti-nodes of these resonances act as three-dimensional hotspots for SERS. For the tapered pillars, SERS enhancement arises from the nanofocusing effect due to the sharp tip on top. SERS experiments were carried out on these substrates using various concentrations of 1,2 bis-(4-pyridyl)-ethylene (BPE), benzenethiol (BT) monolayer and toluene vapor. The results show that SERS enhancement factor of over 0.5 x 10{sup 9} can be achieved, and BPE can be detected down to femto-molar concentration level. The results also show promising potential for the use of these substrates in environmental monitoring of gases and vapors such as volatile organic compounds.

  3. Using UVC technology to enhance IAQ

    Energy Technology Data Exchange (ETDEWEB)

    Scheir, R.; Fencl, F.B. [Steril-Aire USA, Inc., Cerritos, CA (United States)

    1996-02-01

    There are several categories of organisms that can grow and/or spread in modern air handling systems: pathogens--viruses, bacteria, and fungi that cause a range of infectious diseases; allergens--bacteria and mold that cause allergic rhinitis, asthma, humidifier fever, and hypersensitivity pneumonitis; toxins--endotoxins and mycotoxins that cause a variety of toxic effects, irritation, and odors. As HVAC systems move large amounts of outdoor and recirculated air through occupied buildings, they become the conduits by which these unhealthful organisms are spread throughout the spaces they serve. A new UVC technology overcomes previous limitations to enhance IAQ control, effectively and efficiently killing microorganisms that grow, disseminate, and circulate in air handling systems.

  4. Endoscopic Optical Enhancement Technologies in IBD

    Directory of Open Access Journals (Sweden)

    Gian Eugenio Tontini

    2013-11-01

    Full Text Available Optical enhancement technologies are emerging as promising tools to improve diagnosis and clinical management of patients with inflammatory bowel diseases (IBD. The use of dye-based and dye-less chromoendoscopy may improve either characterisation of mucosal inflammation or detection of dysplastic and early neoplastic lesions. Confocal laser endomicroscopy and endocytoscopy both allow for in vivo and real-time microscopic analysis of the tissue. Moreover, the newly introduced molecular imaging has now also become feasible for in vivo diagnosis in IBD. This review focuses on the more recent progresses of advanced endoscopic imaging techniques in the setting of IBD and provides the reader with an updated overview on accepted clinical evidence and ongoing fields of research.

  5. Technology enhanced peer learning and peer assessment

    DEFF Research Database (Denmark)

    Henriksen, Christian Bugge; Bregnhøj, Henrik; Rosthøj, Susanne

    2016-01-01

    This paper explores the application of learning designs featuring formalised and structured technology enhanced peer learning. These include student produced learning elements, peer review discussions and peer assessment in the BSc/MSc level summer course Restoration of European Ecosystems...... and Freshwaters (REEF), the Master thesis preparation seminars for the Master of Public Health (MPH) and the MOOC course Global Environmental Management (GEM). The application of student produced learning elements and peer review discussions is investigated by analyzing quotes from course evaluations...... and performing focus group interviews. The application of peer assessment is investigated by analyzing the agreement of peer assessment between students assessing the same assignment. Our analyses confirm previous research on the value of peer learning and peer assessment and we argue that there could also...

  6. New developments in surface technology and prototyping

    Science.gov (United States)

    Himmer, Thomas; Beyer, Eckhard

    2003-03-01

    Novel lightweight applications in the automotive and aircraft industries require advanced materials and techniques for surface protection as well as direct and rapid manufacturing of the related components and tools. The manufacturing processes presented in this paper are based on multiple additive and subtractive technologies such as laser cutting, laser welding, direct laser metal deposition, laser/plasma hybrid spraying technique or CNC milling. The process chain is similar to layer-based Rapid Prototyping Techniques. In the first step, the 3D CAD geometry is sliced into layers by a specially developed software. These slices are cut by high speed laser cutting and then joined together. In this way laminated tools or parts are built. To improve surface quality and to increase wear resistance a CNC machining center is used. The system consists of a CNC milling machine, in which a 3 kW Nd:YAG laser, a coaxial powder nozzle and a digitizing system are integrated. Using a new laser/plasma hybrid spraying technique, coatings can be deposited onto parts for surface protection. The layers show a low porosity and high adhesion strength, the thickness is up to 0.3 mm, and the lower effort for preliminary surface preparation reduces time and costs of the whole process.

  7. Fluid Mechanics of Biological Surfaces and their Technological Application

    Science.gov (United States)

    Bechert, D. W.; Bruse, M.; Hage, W.; Meyer, R.

    A survey is given on fluid-dynamic effects caused by the structure and properties of biological surfaces. It is demonstrated that the results of investigations aiming at technological applications can also provide insights into biophysical phenomena. Techniques are described both for reducing wall shear stresses and for controlling boundary-layer separation. (a) Wall shear stress reduction was investigated experimentally for various riblet surfaces including a shark skin replica. The latter consists of 800 plastic model scales with compliant anchoring. Hairy surfaces are also considered, and surfaces in which the no-slip condition is modified. Self-cleaning surfaces such as that of lotus leaves represent an interesting option to avoid fluid-dynamic deterioration by the agglomeration of dirt. An example of technological implementation is discussed for riblets in long-range commercial aircraft. (b) Separation control is also an important issue in biology. After a few brief comments on vortex generators, the mechanism of separation control by bird feathers is described in detail. Self-activated movable flaps (=artificial bird feathers) represent a high-lift system enhancing the maximum lift of airfoils by about 20%. This is achieved without perceivable deleterious effects under cruise conditions. Finally, flight experiments on an aircraft with laminar wing and movable flaps are presented.

  8. Surface-enhanced Raman spectroscopy of pterins

    Science.gov (United States)

    Smyth, Ciarán A.; Mirza, Inam; Lunney, James G.; McCabe, Eithne M.

    2012-03-01

    Raman spectroscopy is a useful technique in the identification and characterisation of compounds, but in terms of sensitivity its application is limited. With respect to this the discovery of the surface-enhanced Raman scattering (SERS) phenomenon has proved monumental, and much research has been carried out over the past 30 years developing the technique. Pterins are biological compounds that are found in nature in colour pigmentation and in mammalian metabolic pathways. Moreover, they have been identified in abnormal concentrations in cancer patients, suggesting potential applications in cancer diagnostics. SERS is an ideal technique to identify these compounds, and both nanoparticle suspensions and pulsed laser deposited nanoparticle substrates have been used to examine the spectra of xanthopterin, both in aqueous solution and in different pH environments.

  9. Flight Deck Display Technologies for 4DT and Surface Equivalent Visual Operations

    Science.gov (United States)

    Prinzel, Lawrence J., III; Jones, Denis R.; Shelton, Kevin J.; Arthur, Jarvis J., III; Bailey, Randall E.; Allamandola, Angela S.; Foyle, David C.; Hooey, Becky L.

    2009-01-01

    NASA research is focused on flight deck display technologies that may significantly enhance situation awareness, enable new operating concepts, and reduce the potential for incidents/accidents for terminal area and surface operations. The display technologies include surface map, head-up, and head-worn displays; 4DT guidance algorithms; synthetic and enhanced vision technologies; and terminal maneuvering area traffic conflict detection and alerting systems. This work is critical to ensure that the flight deck interface technologies and the role of the human participants can support the full realization of the Next Generation Air Transportation System (NextGen) and its novel operating concepts.

  10. Exploring design principles for technology-enhanced workplace learning

    NARCIS (Netherlands)

    Esther van der Stappen; Dr. Ilya Zitter

    2016-01-01

    From the article: "Abstract, technology-enhanced learning can be used to replicate existing teaching practices, supplement existing teaching or transform teaching and/or learning process and outcomes. Enhancing workplace learning, which is integrated into higher professional education, with

  11. A Taxonomy of Information Technology-Enhanced Pricing Strategies

    NARCIS (Netherlands)

    Dixit, A.; Whipple, T.W.; Zinkhan, G.M.; Gailey, E.

    2008-01-01

    As a result of evolving technology, opportunities for innovative pricing strategies continuously emerge. The authors provide an updated taxonomy to show how such emerging strategies relate to recent technological advances. Specifically, they cite increased availability of information, enhanced

  12. Enhanced situational technologies applied to ship channels

    Science.gov (United States)

    Helgeson, Michael A.; Wacker, Roger A.

    1997-06-01

    The Houston Ship Channel ranks as America's number one port in foreign tonnage by welcoming more than 50,000 cargo ships and barges annually. Locally 196,000 jobs, 5.5 billion dollars in business revenue and 213 million dollars in taxes are generated. Unfortunately, 32 days of each year vessel traffic stops for hours due to fog causing an estimated 40- 100 million dollars loss as ships idly wait in the channel for weather to clear. In addition, poor visibility has contributed to past vessel collisions which have resulted in channel closure, and associated damage to property and the environment. Today's imaging technology for synthetic vision systems and enhanced situational awareness systems offers a new solution to this problem. Whereas, typically these systems have been targeted at aircraft landing systems the channel navigation application provides a peripheral ground based market. This paper describes two imaging solutions to the problem. One using an active 35 GHz scanning radar and the other using a 94 GHz passive millimeter wave camera.

  13. High Density Periodic Metal Nanopyramids for Surface Enhanced Raman Spectroscopy

    NARCIS (Netherlands)

    Jin, Mingliang

    2012-01-01

    The work presented in this thesis is focused on two areas. First, a new type of nanotextured noble-metal surface has been developed. The new nanotextured surface is demonstrated to enhance inelastic (Raman) scattering, called surface enhanced Raman scattering (SERS), from molecules adsorbed on the

  14. Enhancing the visibility of new technologies

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    After several years of experience and reflection on the subject of technology transfer, CERN has formalised its policy for managing the intellectual property linked to its technology transfer activities.   The new Policy on the Management of Intellectual Property in Technology Transfer activities at CERN was approved in March this year. The aim of the policy is to clarify the basic principles governing technology transfer and the management of the associated intellectual property. The document also lays down the principles governing the redistribution of the income generated by technology transfer and provides for a fund to be set up to give financial support to knowledge and technology transfer projects. "Our main aim is to do everything we can to facilitate the actual transfer of CERN technologies and know-how with potential applications in other research fields or in industrial processes or products," says Bernard Denis, who is a member of the Knowledge and Technology Transfer (...

  15. Using Technology to Enhance an Automotive Program

    Science.gov (United States)

    Ashton, Denis

    2009-01-01

    Denis Ashton uses technology in his automotive technology program at East Valley Institute of Technology (EVIT) to positively impact student outcomes. Ashton, the department chair for the automotive programs at EVIT, in Mesa, Arizona, says that using an interactive PowerPoint curriculum makes learning fun for students and provides immediate…

  16. On the adoption of privacy-enhancing technologies

    OpenAIRE

    Caulfield, T.; Ioannidis, C.; Pym, D.

    2016-01-01

    We propose a model, based on the work of Brock and Durlauf, which looks at how agents make choices between competing technologies, as a framework for exploring aspects of the economics of the adoption of privacy-enhancing technologies. In order to formulate a model of decision-making among choices of technologies by these agents, we consider the following: context, the setting in which and the purpose for which a given technology is used; requirement, the level of privacy that the technology ...

  17. Do we need teachers as designers of technology enhanced learning?

    NARCIS (Netherlands)

    Kirschner, Paul A.

    2016-01-01

    In this special issue, five teams of researchers discuss different aspects of the teacher as designer of technology enhanced learning situations. This final contribution critically discusses if and how teachers as designers of technology enhanced learning might (not) be feasible or even desirable.

  18. Long Term 1 Enhanced Surface Water Treatment Rule Documents

    Science.gov (United States)

    The Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) builds on the requirements of the Surface Water Treatment Rule and specifies treatment requirements to address Cryptosporidium m and other microbial contaminants in public water systems.

  19. Surface- and tip-enhanced raman spectroscopy in catalysis

    NARCIS (Netherlands)

    Hartman, Thomas; Wondergem, Caterina S.; Kumar, Naresh; van den Berg, Albert; Weckhuysen, Bert M.

    2016-01-01

    Surface- and tip-enhanced Raman spectroscopy (SERS and TERS) techniques exhibit highly localized chemical sensitivity, making them ideal for studying chemical reactions, including processes at catalytic surfaces. Catalyst structures, adsorbates, and reaction intermediates can be observed in low

  20. Surface- and Tip-Enhanced Raman Spectroscopy in Catalysis

    NARCIS (Netherlands)

    Hartman, Thomas|info:eu-repo/dai/nl/412640635; Wondergem, Caterina S.; Kumar, Naresh; van den Berg, Albert; Weckhuysen, Bert M.|info:eu-repo/dai/nl/285484397

    2016-01-01

    Surface- and tip-enhanced Raman spectroscopy (SERS and TERS) techniques exhibit highly localized chemical sensitivity, making them ideal for studying chemical reactions, including processes at catalytic surfaces. Catalyst structures, adsorbates, and reaction intermediates can be observed in low

  1. Production Well Performance Enhancement using Sonication Technology

    Energy Technology Data Exchange (ETDEWEB)

    Adewumi, Michael A; Ityokumbul, M Thaddeus; Watson, Robert W; Eltohami, Eltohami; Farias, Mario; Heckman, Glenn; Houlihan, Brendan; Karoor, Samata Prakash; Miller, Bruce G; Mohammed, Nazia; Olanrewaju, Johnson; Ozdemir, Mine; Rejepov, Dautmamed; Sadegh, Abdallah A; Quammie, Kevin E; Zaghloul, Jose; Hughes, W Jack; Montgomery, Thomas C

    2005-12-31

    The objective of this project was to develop a sonic well performance enhancement technology that focused on near wellbore formation damage. In order to successfully achieve this objective, a three-year project was defined. The entire project was broken into four tasks. The overall objective of all this was to foster a better understanding of the mechanisms involved in sonic energy interactions with fluid flow in porous media and adapt such knowledge for field applications. The fours tasks are: • Laboratory studies • Mathematical modeling • Sonic tool design and development • Field demonstration The project was designed to be completed in three years; however, due to budget cuts, support was only provided for the first year, and hence the full objective of the project could not be accomplished. This report summarizes what was accomplished with the support provided by the US Department of Energy. Experiments performed focused on determining the inception of cavitation, studying thermal dissipation under cavitation conditions, investigating sonic energy interactions with glass beads and oil, and studying the effects of sonication on crude oil properties. Our findings show that the voltage threshold for onset of cavitation is independent of transducer-hydrophone separation distance. In addition, thermal dissipation under cavitation conditions contributed to the mobilization of deposited paraffins and waxes. Our preliminary laboratory experiments suggest that waxes are mobilized when the fluid temperature approaches 40°C. Experiments were conducted that provided insights into the interactions between sonic wave and the fluid contained in the porous media. Most of these studies were carried out in a slim-tube apparatus. A numerical model was developed for simulating the effect of sonication in the nearwellbore region. The numerical model developed was validated using a number of standard testbed problems. However, actual application of the model for scale

  2. A New Role for Music Technology: Enhancing Literacy

    Science.gov (United States)

    Nardo, Rachel

    2009-01-01

    General music teachers have a technology tool that not only helps students sing better, it helps them read better! Carry-a-Tune or Singing Coach--the technology that received a rave review from former "General Music Today" technology columnist Kirk Kassner in 2005--is now being offered in an enhanced version called TUNEin[TM] to READING.…

  3. Enhanced Geothermal Systems (EGS) Well Construction Technology Evaluation Report

    Energy Technology Data Exchange (ETDEWEB)

    Polsky, Yarom [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Capuano, Louis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Finger, John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Huh, Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Knudsen, Steve [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Chip, A.J. Mansure [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Raymond, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Swanson, Robert [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2008-12-01

    This report provides an assessment of well construction technology for EGS with two primary objectives: 1. Determining the ability of existing technologies to develop EGS wells. 2. Identifying critical well construction research lines and development technologies that are likely to enhance prospects for EGS viability and improve overall economics.

  4. Prototyping Feedback for Technology Enhanced Learning

    DEFF Research Database (Denmark)

    Cojocaru, Dorian; Spikol, Daniel; Friesel, Anna

    2016-01-01

    The development of new educational technologies, in the area of practical activities is the main aim of the FP7 PELARS project. As part of the constructivist learning scenarios, according to the project proposal, the development and evaluation of technology designs are envisaged, for analytic data...

  5. Computer Technology-Infused Learning Enhancement

    Science.gov (United States)

    Keengwe, Jared; Anyanwu, Longy O.

    2007-01-01

    The purpose of the study was to determine students' perception of instructional integration of computer technology to improve learning. Two key questions were investigated in this study: (a) What is the students' perception of faculty integration of computer technology into classroom instruction? (b) To what extent does the students' perception of…

  6. Surface-enhanced Raman spectroscopy: nonlocal limitations

    DEFF Research Database (Denmark)

    Toscano, Giuseppe; Raza, S.; Xiao, Sanshui

    2012-01-01

    Giant field enhancement and field singularities are a natural consequence of the commonly employed local-response framework. We show that a more general nonlocal treatment of the plasmonic response leads to new and possibly fundamental limitations on field enhancement with important consequences...

  7. A combination of concave/convex surfaces for field-enhancement optimization: the indented nanocone.

    Science.gov (United States)

    García-Etxarri, Aitzol; Apell, Peter; Käll, Mikael; Aizpurua, Javier

    2012-11-05

    We introduce a design strategy to maximize the Near Field (NF) enhancement near plasmonic antennas. We start by identifying and studying the basic electromagnetic effects that contribute to the electric near field enhancement. Next, we show how the concatenation of a convex and a concave surface allows merging all the effects on a single, continuous nanoantenna. As an example of this NF maximization strategy, we engineer a nanostructure, the indented nanocone. This structure, combines all the studied NF maximization effects with a synergistic boost provided by a Fano-like interference effect activated by the presence of the concave surface. As a result, the antenna exhibits a NF amplitude enhancement of ~ 800, which transforms into ~1600 when coupled to a perfect metallic surface. This strong enhancement makes the proposed structure a robust candidate to be used in field enhancement based technologies. Further elaborations of the concept may produce even larger and more effective enhancements.

  8. Surface engineering for enhanced performance against wear

    CERN Document Server

    2013-01-01

    Surface Engineering constitutes a variety of processes and sub processes. Each chapter of this work covers specific processes by experts working in the area. Included for each topic are tribological performances for each process as well as results of recent research. The reader also will benefit from in-depth studies of diffusion coatings, nanocomposite films for wear resistance, surfaces for biotribological applications, thin-film wear, tribology of thermal sprayed coatings, hardfacing, plating for tribology and high energy beam surface modifications. Material scientists as well as engineers working with surface engineering for tribology will be particularly interested in this work.

  9. Making human enamel and dentin surfaces superwetting for enhanced adhesion

    Science.gov (United States)

    Vorobyev, A. Y.; Guo, Chunlei

    2011-11-01

    Good wettability of enamel and dentin surfaces is an important factor in enhancing adhesion of restorative materials in dentistry. In this study, we developed a femtosecond laser surface texturing approach that makes both the enamel and dentine surfaces superwetting. In contrast to the traditional chemical etching that yields random surface structures, this approach produces engineered surface structures. The surface structure engineered and tested here is an array of parallel microgrooves that generates a strong capillary force. Due to the powerful capillary action, water is rapidly sucked into this engineered surface structure and spreads even on a vertical surface.

  10. Surface Plasmon Enhanced Phosphorescent Organic Light Emitting Diodes

    Energy Technology Data Exchange (ETDEWEB)

    Guillermo Bazan; Alexander Mikhailovsky

    2008-08-01

    The objective of the proposed work was to develop the fundamental understanding and practical techniques for enhancement of Phosphorescent Organic Light Emitting Diodes (PhOLEDs) performance by utilizing radiative decay control technology. Briefly, the main technical goal is the acceleration of radiative recombination rate in organometallic triplet emitters by using the interaction with surface plasmon resonances in noble metal nanostructures. Increased photonic output will enable one to eliminate constraints imposed on PhOLED efficiency by triplet-triplet annihilation, triplet-polaron annihilation, and saturation of chromophores with long radiative decay times. Surface plasmon enhanced (SPE) PhOLEDs will operate more efficiently at high injection current densities and will be less prone to degradation mechanisms. Additionally, introduction of metal nanostructures into PhOLEDs may improve their performance due to the improvement of the charge transport through organic layers via multiple possible mechanisms ('electrical bridging' effects, doping-like phenomena, etc.). SPE PhOLED technology is particularly beneficial for solution-fabricated electrophosphorescent devices. Small transition moment of triplet emitters allows achieving a significant enhancement of the emission rate while keeping undesirable quenching processes introduced by the metal nanostructures at a reasonably low level. Plasmonic structures can be introduced easily into solution-fabricated PhOLEDs by blending and spin coating techniques and can be used for enhancement of performance in existing device architectures. This constitutes a significant benefit for a large scale fabrication of PhOLEDs, e.g. by roll-to-roll fabrication techniques. Besides multieexciton annihilation, the power efficacy of PhOLEDs is often limited by high operational bias voltages required for overcoming built-in potential barriers to injection and transport of electrical charges through a device. This problem is

  11. Prototyping Feedback for Technology Enhanced Learning

    DEFF Research Database (Denmark)

    Cojocaru, Dorian; Spikol, Daniel; Friesel, Anna

    2016-01-01

    The development of new educational technologies, in the area of practical activities is the main aim of the FP7 PELARS project. As part of the constructivist learning scenarios, according to the project proposal, the development and evaluation of technology designs are envisaged, for analytic data...... generation for Science, Technology, Engineering and Mathematics (STEM) subjects, such as: technology solutions, infrastructure, activities, assessment, curricula, and classroom furniture and environment designs. Inside four EU national settings, three separate learning contexts are being dealt with – from...... secondary-level high school STEM learning environments to post-secondary level engineering classes and design studios. Given this experience and framework, the present paper provides a perspective on the importance of using such research experience and iterative prototyping in real learning environments...

  12. Prototyping Feedback for Technology Enhanced Learning

    DEFF Research Database (Denmark)

    Cojocaru, Dorian; Spikol, Daniel; Friesel, Anna

    2016-01-01

    generation for Science, Technology, Engineering and Mathematics (STEM) subjects, such as: technology solutions, infrastructure, activities, assessment, curricula, and classroom furniture and environment designs. Inside four EU national settings, three separate learning contexts are being dealt with – from...... secondary-level high school STEM learning environments to post-secondary level engineering classes and design studios. Given this experience and framework, the present paper provides a perspective on the importance of using such research experience and iterative prototyping in real learning environments......The development of new educational technologies, in the area of practical activities is the main aim of the FP7 PELARS project. As part of the constructivist learning scenarios, according to the project proposal, the development and evaluation of technology designs are envisaged, for analytic data...

  13. Technologies and countermeasures for gas recovery enhancement

    OpenAIRE

    Ping, Guo; Shasha, Jing; Caizhen, Peng

    2014-01-01

    Since 2000, China has been ranked as one of the top countries in gas production. Nevertheless, the domestic gas production can hardly satisfy the need of national economic development. Besides, an increasing number of gas fields have come to the middle or late development stages, and most gas reservoirs have low recovery efficiency due to the low permeability and water drive nature. Therefore, gas recovery enhancement has become an urgent issue. At present, the oil recovery enhancement is wel...

  14. Signal enhancement of surface enhanced Raman scattering and surface enhanced resonance Raman scattering using in situ colloidal synthesis in microfluidics.

    Science.gov (United States)

    Wilson, Rab; Bowden, Stephen A; Parnell, John; Cooper, Jonathan M

    2010-03-01

    We demonstrate the enhanced analytical sensitivity of both surface enhanced Raman scattering (SERS) and surface enhanced resonance Raman scattering (SERRS) responses, resulting from the in situ synthesis of silver colloid in a microfluidic flow structure, where both mixing and optical interrogation were integrated on-chip. The chip-based sensor was characterized with a model Raman active label, rhodamine-6G (R6G), and had a limit of detection (LOD) of ca. 50 fM (equivalent to single molecule detection). The device was also used for the determination of the natural pigment, scytonemin, from cyanobacteria (as an analogue for extraterrestrial life existing in extreme environments). The observed LOD of approximately 10 pM (ca. <400 molecules) demonstrated the analytical advantages of working with freshly synthesized colloid in such a flow system. In both cases, sensitivities were between 1 and 2 orders of magnitude greater in the microfluidic system than those measured using the same experimental parameters, with colloid synthesized off-chip, under quiescent conditions.

  15. JTEL Winter School for Advanced Technologically Enhanced Learning

    NARCIS (Netherlands)

    Glahn, Christian; Gruber, Marion

    2010-01-01

    Glahn, C., & Gruber, M. (2010). JTEL Winter School for Advanced Technologically Enhanced Learning. In ~mail. Das Magazin des Tiroler Bildungsinstituts, 01/10, März (p. 3-4). Innsbruck: Grillhof, Medienzentrum.

  16. Enhancement of information and communications technologies (ICTs)

    African Journals Online (AJOL)

    ... therefore examines one of these possibilities by the development of Instruction Delivery Expert System for Teachers and also the need and benefits of the proposed expert system. KEYWORDS: Information and Communications Technologies (ICTs), Expert System, Artificial Intelligence, Knowledge Base, Inference Engine, ...

  17. Carbon nanostructured surfaces for enhanced heat transport

    NARCIS (Netherlands)

    Taha, T.J.

    2015-01-01

    The advancement of high performance thermal systems has stimulated interest in methods to improve heat transfer rates. Considerable efforts have been made to increase heat transfer rates by implementing passive convective heat transfer enhancement methods that require no direct consumption of

  18. Heat transfer research on enhanced heating surfaces in pool boiling

    Science.gov (United States)

    Kalawa, Wojciech; Wójcik, Tadeusz M.; Piasecka, Magdalena

    The paper focuses on the analysis of the enhanced surfaces in such applications as boiling heat transfer. The testing measurement module with enhanced heating surfaces was used for pool boiling research. Pool boiling experiments were conducted with distilled water at atmospheric pressure in the vessel using an enhanced sample as the bottom heating surface. The samples are soldered to a copper heating block of the round cross-section .They were placed: in the fluid (saturation temperature measurement), under the sample for temperature determination. A vessel made of four flat glass panes was used for visualization. The heated surfaces in contact with the fluid differed in roughness were smooth or enhanced. This paper analyzes the effects of the microstructured heated surface on the heat transfer coefficient. The results are presented as relationships between the heat transfer coefficient and the heat flux and as boiling curves. The experimental data obtained for the two types of enhanced heated surfaces was compared with the results recorded for the smooth heated surface. The highest local values of the heat transfer coefficient were reported for the enhanced surfaces.

  19. Nanoparticles and intracellular applications of surface-enhanced Raman spectroscopy.

    Science.gov (United States)

    Taylor, Jack; Huefner, Anna; Li, Li; Wingfield, Jonathan; Mahajan, Sumeet

    2016-08-15

    Surface-enhanced Raman spectrocopy (SERS) offers ultrasensitive vibrational fingerprinting at the nanoscale. Its non-destructive nature affords an ideal tool for interrogation of the intracellular environment, detecting the localisation of biomolecules, delivery and monitoring of therapeutics and for characterisation of complex cellular processes at the molecular level. Innovations in nanotechnology have produced a wide selection of novel, purpose-built plasmonic nanostructures capable of high SERS enhancement for intracellular probing while microfluidic technologies are being utilised to reproducibly synthesise nanoparticle (NP) probes at large scale and in high throughput. Sophisticated multivariate analysis techniques unlock the wealth of previously unattainable biomolecular information contained within large and multidimensional SERS datasets. Thus, with suitable combination of experimental techniques and analytics, SERS boasts enormous potential for cell based assays and to expand our understanding of the intracellular environment. In this review we trace the pathway to utilisation of nanomaterials for intracellular SERS. Thus we review and assess nanoparticle synthesis methods, their toxicity and cell interactions before presenting significant developments in intracellular SERS methodologies and how identified challenges can be addressed.

  20. Recommender systems for technology enhanced learning research trends and applications

    CERN Document Server

    Manouselis, Nikos; Verbert, Katrien

    2014-01-01

    Presents cutting edge research from leading experts in the growing field of Recommender Systems for Technology Enhanced Learning (RecSys TEL) International contributions are included to demonstrate the merging of various efforts and communities Topics include: Linked Data and the Social Web as Facilitators for TEL Recommender Systems in Research and Practice, Personalised Learning-Plan Recommendations in Game-Based Learning and Recommendations from Heterogeneous Sources in a Technology Enhanced Learning Ecosystem

  1. Test and Evaluation Enhancements for Cognitive Radio Technologies

    Science.gov (United States)

    2015-05-13

    Final Report: Test and Evaluation Enhancements for Cognitive Radio Technologies Report Title This document serves as the final report for the...Instrumentation Grant (W911NF-14-1-0042) TEST & EVALUATION ENHANCEMENTS FOR COGNITIVE RADIO TECHNOLOGIES Final Report Dr. Willie L. Thompson, II...software-defined radios , cognitive radios , and other embedded systems. o 8-GHz, 40-GSa/s Digital Signal Analyzer o 136-Channel, 1.4-GHz State High

  2. Enhancement of focused jets by using surface microbubbles

    Science.gov (United States)

    Yukisada, Ryosuke; Kiyama, Akihito; Zhang, Xuehua; Tagawa, Yoshiyuki

    2017-11-01

    Focused liquid jets are important for various key technologies, such as material deposition and automated pipetting. It has been challenging to create high speed jets of viscous liquids. Our latest work showed that it is possible to generate viscous jets by applying sudden acceleration to the liquid (Onuki et al., J. J. Multi. Flow, 2015). It was observed that under certain conditions cavitation bubbles form in the liquid, making important contribution to the increment of jet velocity (Kiyama et al., JFM, 2016). The increased velocity depends on the maximum size of expanding bubbles. Thus, for controlling the velocity of focused jets, it is crucial to control the bubble expansion. In this study, we investigate the effects of surface microbubbles on the focused jets. Before the impact is performed, the microbubbles are produced on an inner wall of the liquid container by using water-ethanol exchange technique. We experimentally measure the jet velocity and bubble motion utilizing a high-speed camera. It is found that surface microbubbles expand upon the impact, enhancing the increment of jet velocity under the conditions that do not trigger cavitation inception in the bulk liquid. JSPS KAKENHI Grant Numbers 26709007 and 17H01246.

  3. Speech Enhancement Based on Compressed Sensing Technology

    Directory of Open Access Journals (Sweden)

    Huiyan Xu

    2014-10-01

    Full Text Available Compressed sensing (CS is a sampled approach on signal sparsity-base, and it can effectively extract the information which is contained in the signal. This paper presents a noisy speech enhancement new method based on CS process. Algorithm uses a voice sparsity in the discrete fast Fourier transform (Fast Fourier transform, FFT, and complex domain observation matrix is designed, and the noisy speech compression measurement and de-noising are made by soft threshold, and the speech signal is sparsely reconstructed by separable approximation (Sparse Reconstruction by Separable Approximation, SpaRSA algorithm to restore, speech enhancement is improved. Experimental results show that the denoising compression reconstruction of the noisy signal is done in the algorithm, SNR margin is improved greatly, and the background noise can been more effectively suppressed.

  4. New technologies of enhanced oil recovery

    Directory of Open Access Journals (Sweden)

    Paweł Wojnarowski

    2006-10-01

    Full Text Available It is known from the literature that up to 27 % of oil in oilfields can be produced using primary and hydration methods. The efficiency of production can be increased by employing more advanced methods, i.e. EOR. The Polish Oil and Gas Company iwork with Polish oilfields, where currently primary methods are applied, but the Polish experiences with EOR date back to the years 1932-1987. In view of high oil prices, reconsidering EOR as a production method is economically justifiable. Therefore, it is purposeful to implement new pilot technologies, aimed at implementing new technologies, understanding accompanying phenomena, and calibrating of simulation models, including economical models for an optimal control of the oilfield exploitation. World’s new exploitation methods worked out in the last few years and suggestions for their implementation in Polish conditions are presented in the paper

  5. Enhancing e-Learning Content by Using Semantic Web Technologies

    Science.gov (United States)

    García-González, Herminio; Gayo, José Emilio Labra; del Puerto Paule-Ruiz, María

    2017-01-01

    We describe a new educational tool that relies on Semantic Web technologies to enhance lessons content. We conducted an experiment with 32 students whose results demonstrate better performance when exposed to our tool in comparison with a plain native tool. Consequently, this prototype opens new possibilities in lessons content enhancement.

  6. Recommender Systems for Technology Enhanced Learning: Research Trends & Applications

    NARCIS (Netherlands)

    Manouselis, Nikos; Verbert, Katrien; Drachsler, Hendrik; Santos, Olga

    2014-01-01

    As an area, Technology Enhanced Learning (TEL) aims to design, develop and test socio-technical innovations that will support and enhance learning practices of individuals and organizations. Information retrieval is a pivotal activity in TEL and the deployment of recommender systems has attracted

  7. The potential use of mobile technology: enhancing accessibility and ...

    African Journals Online (AJOL)

    The potential use of mobile technology: enhancing accessibility and communication in a blended learning course. Tabisa Mayisela. Centre for Learning and Teaching Development, Walter Sisulu University, South Africa tmayisela@wsu.ac.za. Mobile technology is increasingly being used to support blended learning ...

  8. Competence Models in Technology-enhanced Competence-based Learning

    NARCIS (Netherlands)

    Sampson, Demetrios; Fytros, Demetrios

    2008-01-01

    Please cite as: Sampson, D., & Fytros, D. (2008). Competence Models in Technology-enhanced Competence-based Learning. In H. H. Adelsberger, Kinshuk, J. M. Pawlowski & D. Sampson (Eds.), International Handbook on Information Technologies for Education and Training, 2nd Edition, Springer, June 2008

  9. Organisational Culture and Technology-Enhanced Innovation in Higher Education

    Science.gov (United States)

    Zhu, Chang

    2015-01-01

    Higher education institutions are evolving and technology often plays a central role in their transformations. Educational changes benefit from a supportive environment. The study examines the relationship between organisational culture and teachers' perceptions of and responses to technology-enhanced innovation among Chinese universities. A…

  10. Condensation Enhancement by Surface Porosity: Three-Stage Mechanism.

    Science.gov (United States)

    Yarom, Michal; Marmur, Abraham

    2015-08-18

    Surface defects, such as pores, cracks, and scratches, are naturally occurring and commonly found on solid surfaces. However, the mechanism by which such imperfections promote condensation has not been fully explored. In the current paper we thermodynamically analyze the ability of surface porosity to enhance condensation on a hydrophilic solid. We show that the presence of a surface-embedded pore brings about three distinct stages of condensation. The first is capillary condensation inside the pore until it is full. This provides an ideal hydrophilic surface for continuing the condensation. As a result, spontaneous condensation and wetting can be achieved at lower vapor pressure than on a smooth surface.

  11. Raman and Surface Enhanced Raman of Biological Material

    National Research Council Canada - National Science Library

    Guicheteau, Jason A; Gonser, Kristina; Christesen, Steven Dale

    2004-01-01

    .... Vibrational spectroscopic methods such as Raman and surface enhanced Raman scattering (SERS) provide rapid detailed fingerprint information about the molecular composition of biomaterial in a non-destructive manner...

  12. Enhanced Prediction of Gear Tooth Surface Fatigue Life Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Sentient will develop an enhanced prediction of gear tooth surface fatigue life with rigorous analysis of the tribological phenomena that contribute to pitting...

  13. In situ surface-enhanced raman spectroelectrochemical analysis system with a hemin modified nanostructured gold surface

    NARCIS (Netherlands)

    Yuan, Tao; Le Thi Ngoc, Loan; van Nieuwkasteele, Jan William; Odijk, Mathieu; van den Berg, Albert; Permentier, Hjalmar; Bischoff, Rainer; Carlen, Edwin

    2015-01-01

    An integrated surface-enhanced Raman scattering (SERS) spectroelectrochemical (SEC) analysis system is presented that combines a small volume microfluidic sample chamber (<100 mu L) with a compact three-electrode configuration for in situ surface-enhanced Raman spectroelectrochemistry. The SEC

  14. In situ surface-enhanced Raman spectroelectrochemical analysis system with a hemin modified nanostructured gold surface

    NARCIS (Netherlands)

    Yuan, Tao; Le Thi Ngoc, Loan; van Nieuwkasteele, Jan; Odijk, Mathieu; van den Berg, Albert; Permentier, Hjalmar; Bischoff, Rainer; Carlen, Edwin T

    2015-01-01

    An integrated surface-enhanced Raman scattering (SERS) spectroelectrochemical (SEC) analysis system is presented that combines a small volume microfluidic sample chamber (<100 μL) with a compact three-electrode configuration for in situ surface-enhanced Raman spectroelectrochemistry. The SEC system

  15. Metal-coated magnetic nanoparticles for surface enhanced Raman ...

    Indian Academy of Sciences (India)

    We report the optimization and usage of surfactantless, water dispersible Ag and Au-coated –Fe2O3 nanoparticles for applications in surface-enhanced Raman scattering (SERS). These nanoparticles, with plasmonic as well as super paramagnetic properties exhibit Raman enhancement factors of the order of 106 (105) ...

  16. Nanostructured surface enhanced Raman scattering substrates for explosives detection

    DEFF Research Database (Denmark)

    Schmidt, Michael Stenbaek; Olsen, Jesper Kenneth; Boisen, Anja

    2010-01-01

    Here we present a method for trace detection of explosives in the gas phase using novel surface enhanced Raman scattering (SERS) spectroscopy substrates. Novel substrates that produce an exceptionally large enhancement of the Raman effect were used to amplify the Raman signal of explosives molecu...

  17. Moral Enhancement by Technological Means: Possible, Permissible, a Duty?

    Directory of Open Access Journals (Sweden)

    Toni Pustovrh

    2016-10-01

    Full Text Available Attempts to enhance individual and communal morality are as old as human communal living itself. But only recently have philosophers, bioethicists and scientists begun to seriously consider the possibilities and implications of employing technological interventions into the human body, especially the brain, in order to enhance traits and capabilities that underlie what we might term as moral reasoning, action and behavior. Some illicit drugs, prescription pharmaceuticals and non-invasive brain stimulation techniques have been shown to have effects on diminishing or enhancing certain of our mental traits that constitute moral thinking, action and behavior in healthy adults. This hints at the possibility of targeted interventions that might predictably improve individual and communal morality and through it societal cooperation. The first part of the paper will delve into some of the conceptual issues connected with moral enhancement as part of the broader trend of cognitive enhancement and human enhancement in general. The second part will look at some experiments and interventions that support the plausibility of technologically enhancing moral reasoning and moral behavior. The third part will present some of the arguments that have been written both for and against moral enhancement, including whether we might in certain situations have a duty to morally enhance ourselves. The final part looks at some further dilemmas of whether we might already be enhancing ourselves morally through some commonly prescribed pharmaceutical drugs, and what a (further "medicalization" of moral deficits might mean.

  18. Reliability Analysis of Surface Mount Technology (SMT)

    Science.gov (United States)

    1993-03-01

    380, 1981. 7. J. DeVore; "The Mechanisms of Solderability and Solderability Related Failures," General Electric, WCIII-43, Printed Circuit World Convention...34Thermal Cycles and Surface Mounting Attachment Reliability," Circuit World , Vol. Il, 1985 76. J. Collett; "SMT Solder Joint Reliability," IPC-TP-708

  19. Surface potential and morphology mapping to investigate analyte adsorption effects on surface enhanced Raman scattering (SERS).

    Science.gov (United States)

    Chatterjee, Abhijit; Gale, David J G; Grebennikov, Dmytro; Whelan, Liam D; Merschrod S, Erika F

    2017-11-02

    We demonstrate the power of Kelvin probe force microscopy (KPFM) in enabling a comprehensive study of enhancement mechanisms of surface enhanced Raman scattering (SERS) through the correlation of surface electrical and topographical effects. Local electric fields generated on Au/ZnO nanohybrid films impact analyte adsorption, while roughness is linked to hotspot generation. Optimizing the interplay between these two effects yields SERS enhancement factors (EFs) of 106, enabling ppb detection of polycyclic aromatic hydrocarbons (PAHs) in water.

  20. Surface-Enhanced Raman Scattering Physics and Applications

    CERN Document Server

    Kneipp, Katrin; Kneipp, Harald

    2006-01-01

    Almost 30 years after the first reports on surface-enhanced Raman signals, the phenomenon of surface-enhanced Raman scattering (SERS) is now well established. Yet, explaining the enhancement of a spectroscopic signal by fouteen orders of magnitude continues to attract the attention of physicists and chemists alike. And, at the same time and rapidly growing, SERS is becoming a very useful spectroscopic tool with exciting applications in many fields. SERS gained particular interest after single-molecule Raman spectroscopy had been demonstrated. This bookl summarizes and discusses present theoretical approaches that explain the phenomenon of SERS and reports on new and exciting experiments and applications of the fascinating spectroscopic effect.

  1. Functionalising surfaces at the nanoscale using plasma technology.

    Science.gov (United States)

    Moore, R

    2009-01-01

    Plasma technology offers a highly effective toolbox for nanoscale surface engineering of materials. The potential variety of nanoscale features and new properties that can be achieved are reviewed here.

  2. Liquid cell with plasmon lenses for surface enhanced raman spectroscopy.

    Energy Technology Data Exchange (ETDEWEB)

    Vlasko-Vlasov, V.; Joshi-Imre, A.; Bahns, J. T.; Chen, L.; Ocola, L.; Welp, U.

    2010-05-17

    High-fidelity surface enhanced Raman spectra (SERS) of Rhodamine 6G and 2-mercaptopyrimidine liquid solutions are measured using a microfluidic delivery system constructed on a flat silver substrate. Microscopic plasmon lenses patterned in the silver film focus surface plasmons into a subwavelength spot which yields the light amplification required for SERS. The system provides an efficiency similar to traditional colloidal substrates, and allows multiple sample loading. We find that the main contribution to the spectra comes from the molecules directly attached to the silver surface, which gives strong evidence for the chemical enhancement of SERS.

  3. Liquid cell with plasmon lenses for surface enhanced Raman spectroscopy

    Science.gov (United States)

    Vlasko-Vlasov, V.; Joshi-Imre, A.; Bahns, J. T.; Chen, L.; Ocola, L.; Welp, U.

    2010-05-01

    High-fidelity surface enhanced Raman spectra (SERS) of Rhodamine 6G and 2-mercaptopyrimidine liquid solutions are measured using a microfluidic delivery system constructed on a flat silver substrate. Microscopic plasmon lenses patterned in the silver film focus surface plasmons into a subwavelength spot which yields the light amplification required for SERS. The system provides an efficiency similar to traditional colloidal substrates, and allows multiple sample loading. We find that the main contribution to the spectra comes from the molecules directly attached to the silver surface, which gives strong evidence for the chemical enhancement of SERS.

  4. Surface Plasmon-Enhanced Nanoantenna for Localized Fluorescence

    Directory of Open Access Journals (Sweden)

    Isa Kocakarin

    2012-01-01

    Full Text Available Surface plasmon-enhanced gold nanoantenna structures on glass substrate are studied for increased localized electric field and fluorescence at the feed gap locations of the antennas. Dipole, Archimedean balanced spiral, and bowtie and double bowtie geometries are studied for surface plasmon effect. Different flare angles for bowtie geometries are compared to each other. Double bowtie geometry with dual polarization capability exhibited superior performance with almost 56 dB field enhancement factor. We also studied the effect of substrate thickness on electric field enhancement and we found that glass thickness plays a critical role for coherent addition of surface plasmons at the feed gap location. The surface plasmon effect is proven by considering perfect electric conductor model of gold instead of its modified Drude model.

  5. Free-surface modelling technology for compressible and violent flows

    CSIR Research Space (South Africa)

    Heyns, Johan A

    2011-06-01

    Full Text Available This study presents the development of novel modelling technology for compressible and violent free-surface flows, where the new technology aims to extend the capabilities of existing FSM formulations. For the purpose of this study the volume-of-fluid...

  6. ENHANCING STAKEHOLDER ACCEPTANCE OF BIOREMEDIATION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Focht, Will; Albright, Matt; Anex, Robert P., Jr., ed.

    2009-04-21

    This project inquired into the judgments and beliefs of people living near DOE reservations and facilities at Oak Ridge, Tennessee; Hanford, Washington; and Los Alamos, Tennessee about bioremediation of subsurface contamination. The purpose of the investigation was to identify strategies based on these judgments and beliefs for enhancing public support of bioremediation. Several methods were used to collect and analyze data including content analysis of transcripts of face-to-face personal interviews, factor analysis of subjective perspectives using Q methodology, and statistical analysis of results from a large-sample randomized telephone survey. Content analysis of interview transcripts identified themes about public perceptions and constructions of contamination risk, risk management, and risk managers. This analysis revealed that those who have no employment relationship at the sites and are not engaged in technical professions are most concerned about contamination risks. We also found that most interviewees are unfamiliar with subsurface contamination risks and how they can be reduced, believe they have little control over exposure, are frustrated with the lack of progress in remediation, are concerned about a lack of commitment of DOE to full remediation, and distrust site managers to act in the public interest. Concern is also expressed over frequent site management turnover, excessive secrecy, ineffective and biased communication, perceived attempts to talk the public into accepting risk, and apparent lack of concern about community welfare. In the telephone survey, we asked respondents who were aware of site contamination about their perceptions of risk from exposure to subsurface contamination. Response analysis revealed that most people believe that they are at significant risk from subsurface contamination but they acknowledge that more education is needed to calibrate risk perceptions against scientific risk assessments. Most rate their personal

  7. Optical electric-field enhancement at a metal surface arising from surface-plasmon excitation.

    Science.gov (United States)

    Weber, W H; Ford, G W

    1981-03-01

    Surface plasmons can be excited on a metal by an external plane-wave beam through the use of prism or grating couplers or by introducing roughness. This can enhance the electric field at the surface compared with that in the incident beam, and it has been suggested that this effect is an important aspect of surface-enhanced Raman scattering. A general upper limit for this field enhancement is derived on the basis of energy conservation. Numerical results are given for Ag, Au, and Cu. With a perfect coupler on a Ag surface, the maximum increase of the square of the electric field in the 2-3-eV range is congruent with300. On randomly roughened surfaces, the estimated enhancements are of the order of unity.

  8. Proportional control valves integrated in silicon nitride surface channel technology

    NARCIS (Netherlands)

    Groen, Maarten; Groenesteijn, Jarno; Meutstege, Esken; Brookhuis, Robert Anton; Brouwer, Dannis Michel; Lötters, Joost Conrad; Wiegerink, Remco J.

    2015-01-01

    We have designed and realized two types of proportional microcontrol valves in a silicon nitride surface channel technology process. This enables on-die integration of flow controllers with other surface channel devices, such as pressure sensors or thermal or Coriolis-based (mass) flow sensors, to

  9. Development of Polymer Surface Modification Technology for Antistatic

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Hyung; Lee, J.; Kim, B. Y.; Kil, J.; Lee, C.; Kim, Y.; Jeon, Y

    2005-07-15

    It is usually adoptive to mix a surface active agent or coat it on the surface of the film for antistatic of polymer sheets. But It is unable to make antistatic on the low humidity, especially not for packing electric materials such as IC, LSI, and industrial purpose. That's why deposition and coating metal or carbon on the surface of the film are adopted except the problems of the cost and transparency. On the area of styrene resin, the products that have functions of antistatic have been developing with ABS resin. Synthesised a great deal of electro-conductive elements on polymer, not only does the cost rise, but the properties of basic resin diminishes drastically. To stop these problems, it is possibly prospected to adopt the technology, which is able to produce antistatic polymer and use for industrial films, packing materials, and UV protection, to make motorcycle helmets and caps. Compared with functional Polymer, this Polymer is more environmentally friendly and has optical uniformity. Also, it has the properties on visibility. Therefore, it is expected to produce high value-added production. As the surface modification technology such as coating and ion implantation is improved, it will play an important role to make value-added products. As a result, the purpose of the study, applying the surface modification technology for industrial components and functioning product development, is to add surface conductivity on the products which limited for insulation properties among the existing products, develop the mass production technology for slashed costs and the valuation technology for surface modification technology, localize the production equipment to put to practical ion implantation for the low priced products, and develop the polymer surface modification technology for antistatic.

  10. Methodologies and Intelligent Systems for Technology Enhanced Learning

    CERN Document Server

    Gennari, Rosella; Vittorini, Pierpaolo; Prieta, Fernando

    2015-01-01

    This volume presents recent research on Methodologies and Intelligent Systems for Technology Enhanced Learning. It contains the contributions of MIS4TEL 2015, which took place in Salamanca, Spain,. On June 3rd to 5th 2015. Like the previous edition, this proceedings and the conference is an open forum for discussing intelligent systems for Technology Enhanced Learning and empirical methodologies for their design or evaluation MIS4TEL’15 conference has been organized by University of L’aquila, Free University of Bozen-Bolzano and the University of Salamanca.  .

  11. Novel Zirconia Surface Treatments for Enhanced Osseointegration: Laboratory Characterization

    Directory of Open Access Journals (Sweden)

    Ola H. Ewais

    2014-01-01

    Full Text Available Purpose. The aim of this study was to evaluate three novel surface treatments intended to improve osseointegration of zirconia implants: selective infiltration etching treatment (SIE, fusion sputtering (FS, and low pressure particle abrasion (LPPA. The effects of surface treatments on roughness, topography, hardness, and porosity of implants were also assessed. Materials and Methods. 45 zirconia discs (19 mm in diameter × 3 mm in thickness received 3 different surface treatments: selective infiltration etching, low pressure particle abrasion with 30 µm alumina, and fusion sputtering while nontreated surface served as control. Surface roughness was evaluated quantitatively using profilometery, porosity was evaluated using mercury prosimetry, and Vickers microhardness was used to assess surface hardness. Surface topography was analyzed using scanning and atomic force microscopy (α=0.05. Results. There were significant differences between all groups regarding surface roughness (F=1678, P<0.001, porosity (F=3278, P<0.001, and hardness (F=1106.158, P<0.001. Scanning and atomic force microscopy revealed a nanoporous surface characteristic of SIE, and FS resulted in the creation of surface microbeads, while LPPA resulted in limited abrasion of the surface. Conclusion. Within the limitations of the study, changes in surface characteristics and topography of zirconia implants have been observed after different surface treatment approaches. Thus possibilities for enhanced osseointegration could be additionally offered.

  12. Integrated microfluidics system using surface acoustic wave and electrowetting on dielectrics technology.

    Science.gov (United States)

    Li, Y; Fu, Y Q; Brodie, S D; Alghane, M; Walton, A J

    2012-03-01

    This paper presents integrated microfluidic lab-on-a-chip technology combining surface acoustic wave (SAW) and electro-wetting on dielectric (EWOD). This combination has been designed to provide enhanced microfluidic functionality and the integrated devices have been fabricated using a single mask lithographic process. The integrated technology uses EWOD to guide and precisely position microdroplets which can then be actuated by SAW devices for particle concentration, acoustic streaming, mixing and ejection, as well as for sensing using a shear-horizontal wave SAW device. A SAW induced force has also been employed to enhance the EWOD droplet splitting function.

  13. Surface plasmon-enhanced transverse magnetic second-harmonic generation.

    Science.gov (United States)

    Zheng, Wei; Hanbicki, Aubrey T; Jonker, Berry T; Lüpke, Gunter

    2013-11-18

    We present experimental studies on surface plasmon (SP) enhanced transverse magnetic second-harmonic generation (T-MSHG) in single-crystal iron films grown by molecular beam epitaxy at room temperature on MgO (001) substrates. We show that it is possible to achieve both strongly enhanced T-MSHG intensity and high magnetic contrast ratio under attenuated total reflection configuration without using complex heterostructures because MSHG is generated directly at the iron surface where SPs are present. The T-MSHG has a much larger contrast ratio than transverse magneto-optical Kerr effect (T-MOKE) and shows great potential for a new generation of bio-chemical sensors due to its very high surface sensitivity. In addition, by analyzing the experimental results and the simulations based on SP field-enhancement theory, we demonstrate that the second-order susceptibility of MSHG shows great anisotropy and the tensor χ(xzz)(odd) is dominant in our sample.

  14. A Technology Roadmap for Strategic Development of Enhanced Geothermal Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ziagos, John [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Phillips, Benjamin R. [SRA International, Inc. and Geothermal Technologies Office, Washington, DC (United States); Boyd, Lauren [Geothermal Technologies Office, Washington, DC (United States); Jelacic, Allan [SRA International, Inc., Washington, DC (United States); Stillman, Greg [Geothermal Technologies Office, Washington, DC (United States); Hass, Eric [U.S. DOE, Golden, CO (United States)

    2013-02-13

    Realization of EGS development would make geothermal a significant contender in the renewable energy portfolio, on the order of 100+ GWe in the United States alone. While up to 90% of the geothermal power resource in the United States is thought to reside in Enhanced Geothermal Systems (EGS), hurdles to commercial development still remain. The Geothermal Technologies Office, U.S. Department of Energy (DOE), began in 2011 to outline opportunities for advancing EGS technologies on five- to 20-year timescales, with community input on the underlying technology needs that will guide research and ultimately determine commercial success for EGS. This report traces DOE's research investments, past and present, and ties them to these technology needs, forming the basis for an EGS Technology Roadmap to help guide future DOE research. This roadmap is currently open for public comment. Send your comments to geothermal@ee.doe.gov.

  15. Raman and surface enhanced Raman spectroscopic investigation on Lamiaceae plants

    Science.gov (United States)

    Rösch, P.; Popp, J.; Kiefer, W.

    1999-05-01

    The essential oils of Thymus vulgaris and Origanum vulgaris are studied by means of micro-Raman spectroscopy. The containing monoterpenes can be identified by their Raman spectra. Further the essential oils are investigated in their natural environment, the so-called oil cells of these Lamiaceae plants, with surface enhanced Raman spectroscopy (SERS). This method has the advantage to enhance Raman signals and furthermore the SERS effect leads to fluorescence quenching.

  16. dataTEL - Datasets for Technology Enhanced Learning

    NARCIS (Netherlands)

    Drachsler, Hendrik; Verbert, Katrien; Sicilia, Miguel-Angel; Wolpers, Martin; Manouselis, Nikos; Vuorikari, Riina; Lindstaedt, Stefanie; Fischer, Frank

    2011-01-01

    Drachsler, H., Verbert, K., Sicilia, M. A., Wolpers, M., Manouselis, N., Vuorikari, R., Lindstaedt, S., & Fischer, F. (2011). dataTEL - Datasets for Technology Enhanced Learning. STELLAR Alpine Rendez-Vous White Paper. Alpine Rendez-Vous 2011 White paper collection, Nr. 13., France (2011)

  17. Information And Communication Technology: A Tool For Enhancing ...

    African Journals Online (AJOL)

    This paper examined the relevance of Information and Communication Technology (ICT) as a tool for enhancing supervisory effectiveness in Nigerian educational institutions. The paper highlighted various tools of ICT that could be used in educational supervision such as Closed Circuit Television (CCTV) Cameras, e-mails ...

  18. Evaluating Recommender Systems for Technology Enhanced Learning: A Quantitative Survey

    Science.gov (United States)

    Erdt, Mojisola; Fernandez, Alejandro; Rensing, Christoph

    2015-01-01

    The increasing number of publications on recommender systems for Technology Enhanced Learning (TEL) evidence a growing interest in their development and deployment. In order to support learning, recommender systems for TEL need to consider specific requirements, which differ from the requirements for recommender systems in other domains like…

  19. Utilizing Technology to Enhance Learning Environments: The Net Gen Student

    Science.gov (United States)

    Muhammad, Amanda J.; Mitova, Mariana A.; Wooldridge, Deborah G.

    2016-01-01

    It is essential for instructors to understand the importance of classroom technology so they can prepare to use it to personalize students' learning. Strategies for choosing effective electronic tools are presented, followed by specific suggestions for designing enhanced personalized learning using electronic tools.

  20. Mobile Technologies Enhance the E-Learning Opportunity

    Science.gov (United States)

    Chuang, Keh-Wen

    2009-01-01

    The objective of this paper is to identify the mobile technologies that enhance the E-Learning opportunity, examine the educational benefits and implementation issues in mobile learning, discuss the guidelines for implementing effective mobile learning, identify the current application and operation of mobile learning, and discuss the future of…

  1. Technology Enhanced Learning in Programming Courses--International Perspective

    Science.gov (United States)

    Ivanovic, Mirjana; Xinogalos, Stelios; Pitner, Tomáš; Savic, Miloš

    2017-01-01

    Technology enhanced learning (TEL) is increasingly influencing university education, mainly in overcoming disadvantages of direct instruction teaching approaches, and encouraging creativity, problem solving and critical thinking in student-centered, interactive learning environments. In this paper, experiences from object-oriented programming…

  2. Development of effective drying technology for quality enhancement ...

    African Journals Online (AJOL)

    Development of effective drying technology for quality enhancement of whitings fish ( Merlangius merlangius ) ... spent on importation of stockfish, and more job and wealth will be created for the teeming populace while the lovers of stockfish now have access to freshly processed products that would not endanger their life.

  3. Detection of bacterial metabolites through dynamic acquisition from surface enhanced raman spectroscopy substrates integtrated in a centrifugal microfluidic platform

    DEFF Research Database (Denmark)

    Durucan, Onur; Morelli, Lidia; Schmidt, Michael Stenbæk

    2015-01-01

    In this work we present a novel technology that combines the advantages of centrifugal microfluidics with dynamic in-situ Surface Enhanced Raman Spectroscopy (SERS) sensing. Our technology is based on an automated readout system that allows on-line SERS acquisition on a rotating centrifugal...

  4. Surface X-ray studies of catalytic clean technologies.

    Science.gov (United States)

    Lee, Adam F; Prabhakaran, Vinod; Wilson, Karen

    2010-06-14

    The rational design of new heterogeneous catalysts for clean chemical technologies can be accelerated by molecular level insight into surface chemical processes. In situ methodologies, able to provide time-resolved and/or pressure dependent information on the evolution of reacting adsorbed layers over catalytically relevant surfaces, are therefore of especial interest. Here we discuss recent applications of surface X-ray techniques to surface-catalysed oxidations, (de)hydrogenations, C-C coupling, dehalogenation and associated catalyst restructuring, and explore how these may help to shape future sustainable chemistry.

  5. Hacktivism 1-2-3: how privacy enhancing technologies change the face of anonymous hacktivism

    NARCIS (Netherlands)

    Bodó, B.

    2014-01-01

    This short essay explores how the notion of hacktivism changes due to easily accessible, military grade Privacy Enhancing Technologies (PETs). Privacy Enhancing Technologies, technological tools which provide anonymous communications and protect users from online surveillance enable new forms of

  6. Surface-enhanced Raman scattering of suspended monolayer graphene

    Science.gov (United States)

    Huang, Cheng-Wen; Lin, Bing-Jie; Lin, Hsing-Ying; Huang, Chen-Han; Shih, Fu-Yu; Wang, Wei-Hua; Liu, Chih-Yi; Chui, Hsiang-Chen

    2013-11-01

    The interactions between phonons and electrons induced by the dopants or the substrate of graphene in spectroscopic investigation reveal a rich source of interesting physics. Raman spectra and surface-enhanced Raman spectra of supported and suspended monolayer graphenes were measured and analyzed systemically with different approaches. The weak Raman signals are greatly enhanced by the ability of surface-enhanced Raman spectroscopy which has attracted considerable interests. The technique is regarded as wonderful and useful tool, but the dopants that are produced by depositing metallic nanoparticles may affect the electron scattering processes of graphene. Therefore, the doping and substrate influences on graphene are also important issues to be investigated. In this work, the peak positions of G peak and 2D peak, the I 2D/ I G ratios, and enhancements of G and 2D bands with suspended and supported graphene flakes were measured and analyzed. The peak shifts of G and 2D bands between the Raman and SERS signals demonstrate the doping effect induced by silver nanoparticles by n-doping. The I 2D/ I G ratio can provide a more sensitive method to carry out the doping effect on the graphene surface than the peak shifts of G and 2D bands. The enhancements of 2D band of suspended and supported graphenes reached 138, and those of G band reached at least 169. Their good enhancements are helpful to measure the optical properties of graphene. The different substrates that covered the graphene surface with doping effect are more sensitive to the enhancements of G band with respect to 2D band. It provides us a new method to distinguish the substrate and doping effect on graphene.

  7. Automated inspection of solder joints for surface mount technology

    Science.gov (United States)

    Savage, Robert M.; Park, Hyun Soo; Fan, Mark S.

    1993-01-01

    Researchers at NASA/GSFC evaluated various automated inspection systems (AIS) technologies using test boards with known defects in surface mount solder joints. These boards were complex and included almost every type of surface mount device typical of critical assemblies used for space flight applications: X-ray radiography; X-ray laminography; Ultrasonic Imaging; Optical Imaging; Laser Imaging; and Infrared Inspection. Vendors, representative of the different technologies, inspected the test boards with their particular machine. The results of the evaluation showed limitations of AIS. Furthermore, none of the AIS technologies evaluated proved to meet all of the inspection criteria for use in high-reliability applications. It was found that certain inspection systems could supplement but not replace manual inspection for low-volume, high-reliability, surface mount solder joints.

  8. Resonance surface enhanced Raman optical activity of myoglobin as a result of optimized resonance surface enhanced Raman scattering conditions

    DEFF Research Database (Denmark)

    Abdali, Salim; Johannessen, Christian; Nygaard, Jesper

    2007-01-01

    Using Surface enhanced ROA (SEROA), novel results are achieved by combining Raman Optical Activity (ROA) and resonance Surface Enhanced Raman Scattering (SERRS), applied on myoglobin. The novelty of this work is ascribed the first time reporting on chiral results of a study performed on a protein...... has shown that the SERS effect behaves consequently, depending on the concentration ratio of each component, i.e., myoglobin, Ag colloids and NaCl. Accordingly, it is shown here that SERS intensity has its maximum at certain concentration of these components, whereas below or above this value...

  9. Near-Ir surface-enhanced Raman spectrum of lignin

    Science.gov (United States)

    Umesh P. Agarwal; Richard S. Reiner

    2009-01-01

    Compacted powders of commercially available nano- and microparticles of silver were used to successfully induce the surface enhanced Raman scattering (SERS) effect in spruce milled-wood lignin (MWL). For the two silver particle sizes used in this investigation, the spectra were mostly similar. Some general characteristics of the lignin SERS spectrum are described. The...

  10. Surface Reconstruction and Image Enhancement via $L^1$-Minimization

    KAUST Repository

    Dobrev, Veselin

    2010-01-01

    A surface reconstruction technique based on minimization of the total variation of the gradient is introduced. Convergence of the method is established, and an interior-point algorithm solving the associated linear programming problem is introduced. The reconstruction algorithm is illustrated on various test cases including natural and urban terrain data, and enhancement oflow-resolution or aliased images. Copyright © by SIAM.

  11. Ultrasound enhanced plasma surface modification at atmospheric pressure

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Singh, Shailendra Vikram; Norrman, Kion

    irradiation, the water contact angle dropped markedly, and tended to decrease furthermore at higher power. The ultrasonic irradiation during the plasma treatment consistently improved the wettability. Oxygen containing polar functional groups were introduced at the surface by the plasma treatment......, and the oxidation was enhanced by the ultrasonic irradiation, indicating that the adhesive property would be improved....

  12. Ultrasound enhanced plasma surface modification at atmospheric pressure

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Singh, Shailendra Vikram; Norrman, Kion

    2012-01-01

    Efficiency of atmospheric pressure plasma treatment can be highly enhanced by simultaneous high power ultrasonic irradiation onto the treating surface. It is because ultrasonic waves with a sound pressure level (SPL) above ∼140 dB can reduce the thickness of a boundary gas layer between the plasm...

  13. Reactor surface contamination stabilization. Innovative technology summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-11-01

    Contaminated surfaces, such as the face of a nuclear reactor, need to be stabilized (fixed) to avoid airborne contamination during decontamination and decommissioning activities, and to prepare for interim safe storage. The traditional (baseline) method of fixing the contamination has been to spray a coating on the surfaces, but ensuring complete coverage over complex shapes, such as nozzles and hoses, is difficult. The Hanford Site C Reactor Technology Demonstration Group demonstrated innovative technologies to assess stabilization properties of various coatings and to achieve complete coverage of complex surfaces on the reactor face. This demonstration was conducted in two phases: the first phase consisted of a series of laboratory assessments of various stabilization coatings on metal coupons. For the second phase, coatings that passed the laboratory tests were applied to the front face of the C Reactor and evaluated. The baseline coating (Rust-Oleum No. 769) and one of the innovative technologies did not completely cover nozzle assemblies on the reactor face, the most critical of the second-phase evaluation criteria. However, one of the innovative coating systems, consisting of a base layer of foam covered by an outer layer of a polymeric film, was successful. The baseline technology would cost approximately 33% as much as the innovative technology cost of $64,000 to stabilize an entire reactor face (196 m{sup 2} or 2116 ft{sup 2}) with 2,004 nozzle assemblies, but the baseline system failed to provide complete surface coverage.

  14. Principal Leadership for Technology-enhanced Learning in Science

    Science.gov (United States)

    Gerard, Libby F.; Bowyer, Jane B.; Linn, Marcia C.

    2008-02-01

    Reforms such as technology-enhanced instruction require principal leadership. Yet, many principals report that they need help to guide implementation of science and technology reforms. We identify strategies for helping principals provide this leadership. A two-phase design is employed. In the first phase we elicit principals' varied ideas about the Technology-enhanced Learning in Science (TELS) curriculum materials being implemented by teachers in their schools, and in the second phase we engage principals in a leadership workshop designed based on the ideas they generated. Analysis uses an emergent coding scheme to categorize principals' ideas, and a knowledge integration framework to capture the development of these ideas. The analysis suggests that principals frame their thinking about the implementation of TELS in terms of: principal leadership, curriculum, educational policy, teacher learning, student outcomes and financial resources. They seek to improve their own knowledge to support this reform. The principals organize their ideas around individual school goals and current political issues. Principals prefer professional development activities that engage them in reviewing curricula and student work with other principals. Based on the analysis, this study offers guidelines for creating learning opportunities that enhance principals' leadership abilities in technology and science reform.

  15. PECVD silicon carbide surface micromachining technology and selected MEMS applications

    NARCIS (Netherlands)

    Rajaraman, V.; Pakula, L.S.; Yang, H.; French, P.J.; Sarro, P.M.

    2011-01-01

    Attractive material properties of plasma enhanced chemical vapour deposited (PECVD) silicon carbide (SiC) when combined with CMOS-compatible low thermal budget processing provides an ideal technology platform for developing various microelectromechanical systems (MEMS) devices and merging them with

  16. Enhanced Bioactivity and Bacteriostasis of Surface Fluorinated Polyetheretherketone.

    Science.gov (United States)

    Chen, Meiling; Ouyang, Liping; Lu, Tao; Wang, Heying; Meng, Fanhao; Yang, Yan; Ning, Congqin; Ma, Jingzhi; Liu, Xuanyong

    2017-05-24

    Although polyetheretherketone (PEEK) has been considered as a potential orthopedic and dental application material due to its similar elastic modulus as bones, inferior osseointegration and bacteriostasis of PEEK hampers its clinical application. In this work, fluorinated PEEK was constructed via plasma immersion ion implantation (PIII) followed by hydrofluoric acid treatment to ameliorate the osseointegration and antibacterial properties of PEEK. The surface microstructure, composition, and hydrophilicity of all samples were investigated. Rat bone mesenchymal stem cells (rBMSCs) were cultured on their surfaces to estimate bioactivity. The fluorinated PEEK can enhance the cell adhesion, cell spreading, proliferation, and alkaline phosphatase (ALP) activity compared to pristine PEEK. Furthermore, the fluorinated PEEK surface exhibits good bacteriostatic effect against Porphyromonas gingivalis, which is one of the major periodontal pathogens. In summary, we provide an effective route to introduce fluorine and the results reveal that the fluorinated PEEK can enhance the osseointegration and bacteriostasis, which provides a potential candidate for dental implants.

  17. A Lunar Surface System Supportability Technology Development Roadmap

    Science.gov (United States)

    Oeftering, Richard C.; Struk, Peter M.; Taleghani, barmac K.

    2011-01-01

    This paper discusses the establishment of a Supportability Technology Development Roadmap as a guide for developing capabilities intended to allow NASA s Constellation program to enable a supportable, sustainable and affordable exploration of the Moon and Mars. Presented is a discussion of supportability, in terms of space facility maintenance, repair and related logistics and a comparison of how lunar outpost supportability differs from the International Space Station. Supportability lessons learned from NASA and Department of Defense experience and their impact on a future lunar outpost is discussed. A supportability concept for future missions to the Moon and Mars that involves a transition from a highly logistics dependent to a logistically independent operation is discussed. Lunar outpost supportability capability needs are summarized and a supportability technology development strategy is established. The resulting Lunar Surface Systems Supportability Strategy defines general criteria that will be used to select technologies that will enable future flight crews to act effectively to respond to problems and exploit opportunities in an environment of extreme resource scarcity and isolation. This strategy also introduces the concept of exploiting flight hardware as a supportability resource. The technology roadmap involves development of three mutually supporting technology categories, Diagnostics Test and Verification, Maintenance and Repair, and Scavenging and Recycling. The technology roadmap establishes two distinct technology types, "Embedded" and "Process" technologies, with different implementation and thus different criteria and development approaches. The supportability technology roadmap addresses the technology readiness level, and estimated development schedule for technology groups that includes down-selection decision gates that correlate with the lunar program milestones. The resulting supportability technology roadmap is intended to develop a set

  18. International Workshop on Evidence-Based Technology Enhanced Learning

    CERN Document Server

    Gennari, Rosella; Marenzi, Ivana; Prieta, Fernando; Rodríguez, Juan

    2012-01-01

    Research on Technology Enhanced Learning (TEL) investigates how information and communication technologies can be designed in order to support pedagogical activities. The workshop proceedings collects contributions concerning evidence based TEL systems, like their design following EBD principles as well as studies or best practices that educators, education stakeholders or psychologists used to diagnose or improve their students' learning skills, including students with specific difficulties. The international ebTEL’12 workshop wants to be a forum in which TEL researchers and practitioners alike can discuss ideas, projects, and lessons related to ebTEL. The workshop takes place in Salamanca, Spain, on March 28th-30th 2012.  

  19. Enhanced Electromagnetic Chirality by Locally Excited Surface Plasmon Polaritons

    CERN Document Server

    Alizadeh, M H

    2015-01-01

    The possibility to enhance chiral light-matter interactions through plasmonic nanostructures provides entirely new opportunities for greatly improving the detection limits of chiroptical spectroscopies down to the single molecule level. The most pronounced of these chiral interactions occur in the ultraviolet (UV) range of the electromagnetic spectrum, which is difficult to access with conventional localized plasmon resonance based sensors. Although Surface Plasmon Polaritons (SPPs) on noble metal films can sustain resonances in the desired spectral range, their transverse magnetic nature has been an obstacle for enhancing chiroptical effects. Here we demonstrate, both analytically and numerically, that SPPs excited by near-field sources can exhibit rich and non-trivial chiral characteristics. In particular, we show that the excitation of SPPs by a chiral source not only results in a locally enhanced optical chirality but also achieves manifold enhancement of net optical chirality. Our finding that SPPs facil...

  20. Surface-enhanced Raman scattering on gold nanotrenches and nanoholes

    KAUST Repository

    Yue, Weisheng

    2012-04-01

    Dependent effects on edge-to-edge distance and incidence polarization in surface-enhanced Raman Scattering (SERS) were studied in detection of 4-mercaptopyridine (4-MPy) molecules absorbed on gold nanotrenches and nanoholes. The gold nanostructures with controllable size and period were fabricated using electron-beam lithography. Large SERS enhancement in detection of 4-MPy molecules on both nanostructred substrates was observed. The SERS enhancement increased exponentially with decrease of edge to-edge distance for both the nanotrenches and nanoholes while keeping the sizes of the nanotrenches and nanoholes unchanged. Investigation of polarization dependence showed that the SERS enhancement of nanotrenches was much more sensitive to the incidence polarizations than that of nanoholes. © 2012 American Scientific Publishers.

  1. Frontiers of surface-enhanced Raman scattering single nanoparticles and single cells

    CERN Document Server

    Ozaki, Yukihiro; Aroca, Ricardo

    2014-01-01

    A comprehensive presentation of Surface-Enhanced Raman Scattering (SERS) theory, substrate fabrication, applications of SERS to biosystems, chemical analysis, sensing and fundamental innovation through experimentation. Written by internationally recognized editors and contributors. Relevant to all those within the scientific community dealing with Raman Spectroscopy, i.e. physicists, chemists, biologists, material scientists, physicians and biomedical scientists. SERS applications are widely expanding and the technology is now used in the field of nanotechnologies, applications to biosystems, nonosensors, nanoimaging and nanoscience.

  2. New and Emerging Technologies for Real-Time Air and Surface Beryllium Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Phifer, B.E. Jr.; Churnetski, E.L.; Cooke, L.E.; Reed, J.J.; Howell, M.L.; Smith, V.D.

    2001-09-01

    In this study, five emerging technologies were identified for real-time monitoring of airborne beryllium: Microwave-Induced Plasma Spectroscopy (MIPS), Aerosol Beam-Focused Laser-Induced Plasma Spectroscopy (ABFLIPS), Laser-Induced Breakdown Spectroscopy (LIBS), Surfaced-Enhanced Raman Scattering (SERS) Spectroscopy, and Micro-Calorimetric Spectroscopy (CalSpec). Desired features of real-time air beryllium monitoring instrumentation were developed from the Y-12 CBDPP. These features were used as guidelines for the identification of potential technologies as well as their unique demonstrated capability to provide real-time monitoring of similar materials. However, best available technologies were considered, regardless of their ability to comply with the desired features. None of the five technologies have the capability to measure the particle size of airborne beryllium. Although reducing the total concentration of airborne beryllium is important, current literature suggests that reducing or eliminating the concentration of respirable beryllium is critical for worker health protection. Eight emerging technologies were identified for surface monitoring of beryllium. CalSpec, MIPS, SERS, LIBS, Laser Ablation, Absorptive Stripping Voltametry (ASV), Modified Inductively Coupled Plasma (ICP) Spectroscopy, and Gamma BeAST. Desired features of real-time surface beryllium monitoring were developed from the Y-12 CBDPP. These features were used as guidelines for the identification of potential technologies. However, the best available technologies were considered regardless of their ability to comply with the desired features.

  3. The application of optical resolution enhancement technology and e-beam direct writing technology in microfabrication

    Science.gov (United States)

    Qiu, Yulin; Chen, Baoqin; Liu, Ming; Xu, Qiuxia; Xue, Lijun; Ren, Liming; Hu, Yong; Long, Shibing; Lu, Jing; Kang, Xiaohui; Li, Ling; Li, Jinru; Tang, Yueke

    2005-01-01

    The Micro-processing & Nano-technology Laboratory at the Institute of Microelectronics, Chinese Academy of Sciences (CAS), is equipped with a GCA 3600F PG&3696, a JBX 6AII & JBX 5000LS EB, and an ETEC MEBES 4700S EB. For a long time we have been engaged in the research and manufacture on Optical Resolution Enhancement Technology (RET) and E-Beam Direct Writing Technology. In this paper the following technologies will be described: PSM, OPC EBDW,EPC,Match & Mixed Lithography technology. Through the application of RET in optical lithography system, we completed the 0.2 um pattern with the g line and I line light source, which is the necessary preparation for 100nm node with 193nm light source. By means of match & mixed lithography and nanofabrication technology, 20nm-50nm gate CMOS transistor and 100nm gate HEMT are successfully developed.

  4. Environmental policies to enhance technological change in the electricity sector

    Science.gov (United States)

    Sunol Del Rio, Eric

    International agreements on climate change mitigation set quantitative carbon emission reduction targets in a country for a given year with respect to a given base year. A central question is then on what time do the new clean and costly technologies need to start functioning to comply with the agreed targets, and under what incentive does the market implement them. The planner's economic problem is to design an incentive that makes the new clean technology less costly than the vintage polluting facility, at the precise time in order to comply with the agreements at minimum cost. Chapter 1 reviews the literature on efficient allocation of pollution, discussing its validity to explain induced technological change. It then presents a simple model of technological change showing that market power determes the optimal adoption time of a new technology. Chapter 2 analyzes the effectiveness of carbon costs in accelerating technological change under different paths of technological progress. Furthermore, the paper examines the influence of market conditions. It shows that emission charges do reduce the firm's optimal adoption time when investment cost paths for the new technology are convex. On the contrary, emission charges may delay the optimal the switching time of a technology when the investment cost path is concave. Chapter 3 explores the results of Chapter 2 in an agent-based model. Simulations of firms adjusting their output a la Cournot show that the effectiveness of carbon costs in accelerating technological change is highly dependant on the number of firms in the market. Moreover, the shape of the technological progress curve is determinant: the effects of carbon charges are not linear on carbon price, and become more uncertain the more concave the investment cost path is. These results show that policies aiming at internalizing pollution costs enhance technological change at very different rates, depending on the actual market conditions in the industry and

  5. Surface chemistry: Key to control and advance myriad technologies

    Science.gov (United States)

    Yates, John T.; Campbell, Charles T.

    2011-01-01

    This special issue on surface chemistry is introduced with a brief history of the field, a summary of the importance of surface chemistry in technological applications, a brief overview of some of the most important recent developments in this field, and a look forward to some of its most exciting future directions. This collection of invited articles is intended to provide a snapshot of current developments in the field, exemplify the state of the art in fundamental research in surface chemistry, and highlight some possibilities in the future. Here, we show how those articles fit together in the bigger picture of this field. PMID:21245359

  6. A Technology Enhanced Learning Model for Quality Education

    Science.gov (United States)

    Sherly, Elizabeth; Uddin, Md. Meraj

    Technology Enhanced Learning and Teaching (TELT) Model provides learning through collaborations and interactions with a framework for content development and collaborative knowledge sharing system as a supplementary for learning to improve the quality of education system. TELT deals with a unique pedagogy model for Technology Enhanced Learning System which includes course management system, digital library, multimedia enriched contents and video lectures, open content management system and collaboration and knowledge sharing systems. Open sources like Moodle and Wiki for content development, video on demand solution with a low cost mid range system, an exhaustive digital library are provided in a portal system. The paper depicts a case study of e-learning initiatives with TELT model at IIITM-K and how effectively implemented.

  7. Technology-enhanced learning in transnational higher education.

    Science.gov (United States)

    Arunasalam, Nirmala

    2016-11-24

    Some university schools of nursing in Australia and the UK have developed collaborative links with Malaysia to deliver part-time Transnational Higher Education (TNHE) post-registration top-up nursing degree courses. It enables nurses trained to diploma level to upgrade to a degree qualification. The views of 18 Malaysian nurses who had studied with one Australian and two UK TNHE universities were explored using a hermeneutic phenomenological approach. Participants recruited via convenience and snowball sampling methods were interviewed in English and Bahasa Malaysia (Malaysian language). Thematic analysis were used to analyse data. Findings indicated nurses' frustration with technology-enhanced teaching and learning and a lack of support throughout the programme. Although nurses developed confidence in using computer technology, they remained disappointed with the level of academic support. The data and some useful strategies outlined provide important insights for TNHE providers, the Malaysian Nursing Board and private hospital employers to consider for enhancing nurses learning and experiences.

  8. Using Technology to Enhance Patient-Physician Interactions.

    Science.gov (United States)

    Voran, David

    2017-05-01

    The computer is an integral part of a clinical office examination room. How a physician simultaneously uses the computer and interacts with patients will either enhance or deter patient engagement in areas of health maintenance and rehabilitation. With the growing emphasis on patient-centered care and management of chronic health conditions, patient engagement plays an ever-increasing role in U.S. health care. This paper reviews and discusses the 4 broad factors that influence the traditional physician-patient examination room interaction: physician computer/technology skills and dexterity, verbal and nonverbal communication, design and spatial arrangement, and hardware considerations. If used effectively, in-room technology will both enhance patient care and engender a greater degree of patient trust in their provider. Copyright © 2017 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  9. Surface-enhanced Raman scattering activity of niobium surface after irradiation with femtosecond laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Victor G. [Faculty of Physics, Sofia University, 5 James Bourchier Blvd., 1164 Sofia (Bulgaria); Georgi Nadjakov Institute of Solid State Physics, BAS, 72 Tzarigradsko Chaussee, 1784 Sofia (Bulgaria); Vlakhov, Emil S. [Georgi Nadjakov Institute of Solid State Physics, BAS, 72 Tzarigradsko Chaussee, 1784 Sofia (Bulgaria); Stan, George E.; Socol, Marcela [National Institute of Material Physics, 105 bis Atomistilor Street, 077125 Magurele-Ilfov (Romania); Zamfirescu, Marian; Albu, Catalina; Mihailescu, Natalia; Negut, Irina; Luculescu, Catalin; Ristoscu, Carmen; Mihailescu, Ion N., E-mail: ion.mihailescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, 077125 Magurele-Ilfov (Romania)

    2015-11-28

    The chemical modification of the niobium (Nb) surface after irradiation with femtosecond laser pulses was investigated by scanning electron microscopy coupled with energy dispersive spectroscopy, atomic force microscopy, grazing incidence X-ray diffraction, and micro-Raman spectroscopy. The physical-chemical analyses indicated that the laser treatment results in oxidation of the Nb surface, as well as in the formation of Nb hydrides. Remarkably, after the samples' washing in ethanol, a strong Surface-Enhanced Raman Scattering (SERS) signal originating from the toluene residual traces was evidenced. Further, it was observed that the laser irradiated Nb surface is able to provide a SERS enhancement of ∼1.3 × 10{sup 3} times for rhodamine 6G solutions. Thus, for the first time it was shown that Nb/Nb oxide surfaces could exhibit SERS functionality, and so one can expect applications in biological/biochemical screening or for sensing of dangerous environmental substances.

  10. Surface-enhanced Raman scattering activity of niobium surface after irradiation with femtosecond laser pulses

    Science.gov (United States)

    Ivanov, Victor G.; Vlakhov, Emil S.; Stan, George E.; Zamfirescu, Marian; Albu, Catalina; Mihailescu, Natalia; Negut, Irina; Luculescu, Catalin; Socol, Marcela; Ristoscu, Carmen; Mihailescu, Ion N.

    2015-11-01

    The chemical modification of the niobium (Nb) surface after irradiation with femtosecond laser pulses was investigated by scanning electron microscopy coupled with energy dispersive spectroscopy, atomic force microscopy, grazing incidence X-ray diffraction, and micro-Raman spectroscopy. The physical-chemical analyses indicated that the laser treatment results in oxidation of the Nb surface, as well as in the formation of Nb hydrides. Remarkably, after the samples' washing in ethanol, a strong Surface-Enhanced Raman Scattering (SERS) signal originating from the toluene residual traces was evidenced. Further, it was observed that the laser irradiated Nb surface is able to provide a SERS enhancement of ˜1.3 × 103 times for rhodamine 6G solutions. Thus, for the first time it was shown that Nb/Nb oxide surfaces could exhibit SERS functionality, and so one can expect applications in biological/biochemical screening or for sensing of dangerous environmental substances.

  11. Ionic enhancement of silica surface nanowear in electrolyte solutions

    KAUST Repository

    Vakarelski, Ivan Uriev

    2012-11-20

    The nanoscale wear and friction of silica and silicon nitride surfaces in aqueous electrolyte solutions were investigated by using sharp atomic force microscope (AFM) cantilever tips coated with silicon nitride. Measurements were carried out in aqueous solutions of varying pH and in monovalent and divalent cation chloride and nitrate solutions. The silica surface was shown to wear strongly in solutions of high pH (≈11.0), as expected, but the presence of simple cations, such as Cs+ and Ca2+, was shown to dramatically effect the wear depth and friction force for the silica surface. In the case of monovalent cations, their hydration enthalpies correlated well with the wear and friction. The weakest hydrated cation of Cs+ showed the most significant enhancement of wear and friction. In the case of divalent cations, a complex dependence on the type of cation was found, where the type of anion was also seen to play an important role. The CaCl2 solution showed the anomalous enhancement of wear depth and friction force, although the solution of Ca(NO3)2 did not. The present results obtained with an AFM tip were also compared with previous nanotribology studies of silica surfaces in electrolyte solutions, and possible molecular mechanisms as to why cations enhance the wear and friction were also discussed. © 2012 American Chemical Society.

  12. Evaluation of metrology technologies for free form surfaces

    DEFF Research Database (Denmark)

    Arámbula, K.; Siller, H.R.; De Chiffre, Leonardo

    2012-01-01

    This research work describes a novel approach for comparing different technologies for free form surface metrology: computerized tomography (CT), photogrammetry and coordinate measuring machines (CMM). The comparison has the aim of providing relevant information for the selection of metrology...... also deals with costs issues, required standards, and necessary additional information when selecting inspection equipment....

  13. Enhanced surrogate models for statistical design exploiting space mapping technology

    DEFF Research Database (Denmark)

    Koziel, Slawek; Bandler, John W.; Mohamed, Achmed S.

    2005-01-01

    We present advances in microwave and RF device modeling exploiting Space Mapping (SM) technology. We propose new SM modeling formulations utilizing input mappings, output mappings, frequency scaling and quadratic approximations. Our aim is to enhance circuit models for statistical analysis...... and yield-driven design. We illustrate our results using a capacitively-loaded two-section impedance transformer, a single-resonator waveguide filter and a six-section H-plane waveguide filter....

  14. Machine Teaching -- A Machine Learning Approach to Technology Enhanced Learning

    OpenAIRE

    Weimer, Markus

    2010-01-01

    Many applications of Technology Enhanced Learning are based on strong assumptions: Knowledge needs to be standardized, structured and most of all externalized into learning material that preferably is annotated with meta-data for efficient re-use. A vast body of valuable knowledge does not meet these assumptions, including informal knowledge such as experience and intuition that is key to many complex activities. We notice that knowledge, even if not standardized, structured and externalized,...

  15. Enhanced Passive Cooling for Waterless-Power Production Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Salvador B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-06-14

    Recent advances in the literature and at SNL indicate the strong potential for passive, specialized surfaces to significantly enhance power production output. Our exploratory computational and experimental research indicates that fractal and swirl surfaces can help enable waterless-power production by increasing the amount of heat transfer and turbulence, when compared with conventional surfaces. Small modular reactors, advanced reactors, and non-nuclear plants (e.g., solar and coal) are ideally suited for sCO2 coolant loops. The sCO2 loop converts the thermal heat into electricity, while the specialized surfaces passively and securely reject the waste process heat in an environmentally benign manner. The resultant, integrated energy systems are highly suitable for small grids, rural areas, and arid regions.

  16. Coal surface control for advanced physical fine coal cleaning technologies

    Energy Technology Data Exchange (ETDEWEB)

    Morsi, B.I.; Chiang, S.H.; Sharkey, A.; Blachere, J.; Klinzing, G.; Araujo, G.; Cheng, Y.S.; Gray, R.; Streeter, R.; Bi, H.; Campbell, P.; Chiarlli, P.; Ciocco, M.; Hittle, L.; Kim, S.; Kim, Y.; Perez, L.; Venkatadri, R.

    1992-01-01

    This final report presents the research work carried out on the Coal Surface Control for Advanced Physical Fine Coal Cleaning Technologies project, sponsored by the US Department of Energy, Pittsburgh Energy Technology Center (DOE/PETC). The project was to support the engineering development of the selective agglomeration technology in order to reduce the sulfur content of US coals for controlling SO[sub 2] emissions (i.e., acid rain precursors). The overall effort was a part of the DOE/PETCs Acid Rain Control Initiative (ARCI). The overall objective of the project is to develop techniques for coal surface control prior to the advanced physical fine coal cleaning process of selective agglomeration in order to achieve 85% pyrite sulfur rejection at an energy recovery greater than 85% based on run-of-mine coal. The surface control is meant to encompass surface modification during grinding and laboratory beneficiation testing. The project includes the following tasks: Project planning; methods for analysis of samples; development of standard beneficiation test; grinding studies; modification of particle surface; and exploratory R D and support. The coal samples used in this project include three base coals, Upper Freeport - Indiana County, PA, Pittsburgh NO. 8 - Belmont County, OH, and Illinois No. 6 - Randolph County, IL, and three additional coals, Upper Freeport - Grant County- WV, Kentucky No. 9 Hopkins County, KY, and Wyodak - Campbell County, WY. A total of 149 drums of coal were received.

  17. Hierarchical surface rough ordered Au particle arrays and their surface enhanced Raman scattering

    Science.gov (United States)

    Duan, Guotao; Cai, Weiping; Luo, Yuanyuan; Li, Yue; Lei, Yong

    2006-10-01

    A simple, effective, and low-cost method is presented to fabricate an ordered Au particle array with hierarchical surface roughness on an indium tin oxide substrate based on an ordered alumina through-pore template, induced by solution dipping on colloidal monolayer, using an electrochemical deposition strategy. The array consists of periodically arranged and isolated Au microparticles, which show nanoscaled surface roughness. Importantly, this hierarchically rough particle array exhibits strong surface-enhanced Raman scattering effect using rhodamine 6G as probe molecules, associated with its surface geometry. Such structure could be useful, e.g., in sensors, biotechnology, and nanodevices.

  18. Nanoparticle Properties and Synthesis Effects on Surface-Enhanced Raman Scattering Enhancement Factor: An Introduction

    Directory of Open Access Journals (Sweden)

    Nathan D. Israelsen

    2015-01-01

    Full Text Available Raman spectroscopy has enabled researchers to map the specific chemical makeup of surfaces, solutions, and even cells. However, the inherent insensitivity of the technique makes it difficult to use and statistically complicated. When Raman active molecules are near gold or silver nanoparticles, the Raman intensity is significantly amplified. This phenomenon is referred to as surface-enhanced Raman spectroscopy (SERS. The extent of SERS enhancement is due to a variety of factors such as nanoparticle size, shape, material, and configuration. The choice of Raman reporters and protective coatings will also influence SERS enhancement. This review provides an introduction to how these factors influence signal enhancement and how to optimize them during synthesis of SERS nanoparticles.

  19. A Process-Oriented Model for Technology-Enhanced Learning

    Science.gov (United States)

    Bonanno, Philip

    A process-oriented model is developed to underpin the initiatives in technology-enhanced learning currently introduced in the Faculty of Education, University of Malta. The need for such initiatives is highlighted considering the educational, economical and social needs of the country. These needs demand a technology-intensive, flexible, learner-oriented approach to education and training. More important they need to be based on an innovative methodology that focuses on learning processes and interactions rather than subject content only. Based on recommendations from different fields of research a process-oriented approach is proposed that considers dimensions and levels of interactions. Interactions are categorized along the domain, technology and community dimensions and across three pedagogical levels - novice, competent and expert learners each having characteristic learning needs. The model is used to develop a programme in TEL integrating epistemology, pedagogy, design principles with use of digital tools.

  20. Enhancing technological innovation in small firms: Role of collaboration

    Science.gov (United States)

    Singh, D.; Khamba, J. S.; Nanda, T.

    2014-07-01

    Contribution of Micro-Small and Medium Enterprises (MSMEs) is highly remarkable in the overall industrial economy of the country. In recent years, the MSME sector has consistently registered higher growth rate compared to the overall industrial sector. With its agility and dynamism, the sector has shown admirable innovativeness and adaptability to survive the recent economic downturn and recession. However, MSMEs growth rate is still at low level. Therefore, it becomes essential for organizations to adopt new technologies or upgrade existing setup to meet continuously changing global market and fulfill customer needs. This paper explores the relationships between different collaboration networks and technological innovation of small firms through an extensive review of literature. The study finds that collaboration with larger enterprises, R&D institutions, universities and government agencies play a significant role in enhancing technological innovation in small firms.

  1. Updated Heliostorm Warning Mission: Enhancements Based on New Technology

    Science.gov (United States)

    Young, Roy M.

    2010-01-01

    The Heliostorm (also referred to as Geostorm) mission has been regarded as the best choice for the first application of solar sail technology. The objective of Heliostorm is to obtain data from an orbit station slightly displaced from the ecliptic at or nearer to the Sun than 0.98 AU, which places it twice as close to the sun as Earth's natural L1 point at 0.993 AU. Heliostorm has been the subject of several mission studies over the past decade, with the most complete study conducted in 1999 in conjunction with a proposed New Millennium Program (NMP) Space Technology 5 (ST-5) flight opportunity. Recently, over a two and one-half year period dating from 2002 through 2005, NASA s In-Space Propulsion Technology Program (ISTP) matured solar sail technology from laboratory components to fully integrated systems, demonstrated in as relevant a space environment as could feasibly be simulated on the ground. Work under this program has yielded promising results for enhanced Heliostorm mission performance. This paper will present the preliminary results of an updated Heliostorm mission design study including the enhancements incorporated during the design, development, analysis and testing of the system ground demonstrator.

  2. Bone surface enhancement in ultrasound images using a new Doppler-based acquisition/processing method

    Science.gov (United States)

    Yang, Xu; Tang, Songyuan; Tasciotti, Ennio; Righetti, Raffaella

    2018-01-01

    Ultrasound (US) imaging has long been considered as a potential aid in orthopedic surgeries. US technologies are safe, portable and do not use radiations. This would make them a desirable tool for real-time assessment of fractures and to monitor fracture healing. However, image quality of US imaging methods in bone applications is limited by speckle, attenuation, shadow, multiple reflections and other imaging artifacts. While bone surfaces typically appear in US images as somewhat ‘brighter’ than soft tissue, they are often not easily distinguishable from the surrounding tissue. Therefore, US imaging methods aimed at segmenting bone surfaces need enhancement in image contrast prior to segmentation to improve the quality of the detected bone surface. In this paper, we present a novel acquisition/processing technique for bone surface enhancement in US images. Inspired by elastography and Doppler imaging methods, this technique takes advantage of the difference between the mechanical and acoustic properties of bones and those of soft tissues to make the bone surface more easily distinguishable in US images. The objective of this technique is to facilitate US-based bone segmentation methods and improve the accuracy of their outcomes. The newly proposed technique is tested both in in vitro and in vivo experiments. The results of these preliminary experiments suggest that the use of the proposed technique has the potential to significantly enhance the detectability of bone surfaces in noisy ultrasound images.

  3. Surface enhanced raman spectroscopy analytical, biophysical and life science applications

    CERN Document Server

    Schlücker, Sebastian

    2013-01-01

    Covering everything from the basic theoretical and practical knowledge to new exciting developments in the field with a focus on analytical and life science applications, this monograph shows how to apply surface-enhanced Raman scattering (SERS) for solving real world problems. From the contents: * Theory and practice of SERS * Analytical applications * SERS combined with other analytical techniques * Biophysical applications * Life science applications including various microscopies Aimed at analytical, surface and medicinal chemists, spectroscopists, biophysicists and materials scientists. Includes a Foreword by the renowned Raman spectroscopist Professor Wolfgang Kiefer, the former Editor-in-Chief of the Journal of Raman Spectroscopy.

  4. [Current views on surface enhanced Raman spectroscopy in microbiology].

    Science.gov (United States)

    Jia, Xiaoxiao; Li, Jing; Qin, Tian; Deng, Aihua; Liu, Wenjun

    2015-05-01

    Raman spectroscopy has generated many branches during the development for more than 90 years. Surface enhanced Raman spectroscopy (SERS) improves SNR by using the interaction between tested materials and the surface of rough metal, as to quickly get higher sensitivity and precision spectroscopy without sample pretreatment. This article describes the characteristic and classification of SERS, and updates the theory and clinical application of SERS. It also summarizes the present status and progress of SERS in various disciplines and illustrates the necessity and urgency of its research, which provides rationale for the application for SERS in microbiology.

  5. Heat Transfer Enhancement in Turbulent Flows by Blocked Surfaces

    Directory of Open Access Journals (Sweden)

    Onur YEMENİCİ

    2013-04-01

    Full Text Available In this study, the heat transfer analyses over flat and blocked surfaces were carried out in turbulent flow under the influence of the block height. A constant-temperature hot wire anemometer was used to the velocity and turbulent intensity measurements, while temperature values were measured by copper-constantan thermocouples. The average Stanton numbers for block heights of 15 and 25 mm were higher than those of flat surface by %38 and %84, respectively. The results showed that the presence of the blocks increased the heat transfer and the enhancement rose with block heights

  6. Surface-enhanced Raman spectroscopy bioanalytical, biomolecular and medical applications

    CERN Document Server

    Procházka, Marek

    2016-01-01

    This book gives an overview of recent developments in RS and SERS for sensing and biosensing considering also limitations, possibilities and prospects of this technique. Raman scattering (RS) is a widely used vibrational technique providing highly specific molecular spectral patterns. A severe limitation for the application of this spectroscopic technique lies in the low cross section of RS. Surface-enhanced Raman scattering (SERS) spectroscopy overcomes this problem by 6-11 orders of magnitude enhancement compared with the standard RS for molecules in the close vicinity of certain rough metal surfaces. Thus, SERS combines molecular fingerprint specificity with potential single-molecule sensitivity. Due to the recent development of new SERS-active substrates, labeling and derivatization chemistry as well as new instrumentations, SERS became a very promising tool for many varied applications, including bioanalytical studies and sensing. Both intrinsic and extrinsic SERS biosensing schemes have been employed to...

  7. From assistive to enhancing technology: should the treatment-enhancement distinction apply to future assistive and augmenting technologies?

    Science.gov (United States)

    Minerva, Francesca; Giubilini, Alberto

    2017-10-14

    The treatment-enhancement distinction is often used to delineate acceptable and unacceptable medical interventions. It is likely that future assistive and augmenting technologies will also soon develop to a level that they might be considered to provide users, in particular those with disabilities, with abilities that go beyond natural human limits, and become in effect an enhancing technology. In this paper, we describe how this process might take place, and discuss the moral implications of such developments. We argue that such developments are morally acceptable and indeed desirable. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  8. Nanoparticles and intracellular applications of surface-enhanced Raman spectroscopy

    OpenAIRE

    Taylor, Jack; Huefner, Anna; Li, Li; Wingfield, Jonathan; Mahajan, Sumeet

    2016-01-01

    Surface-enhanced Raman spectrocopy (SERS) offers ultrasensitive vibrational fingerprinting at the nanoscale. Its non-destructive nature affords an ideal tool for interrogation of the intracellular environment, detecting the localisation of biomolecules, delivery and monitoring of therapeutics and for characterisation of complex cellular processes at the molecular level. Innovations in nanotechnology have produced a wide selection of novel, purpose-built plasmonic nanostructures capable of hig...

  9. Surface Conductive Graphene-Wrapped Micromotors Exhibiting Enhanced Motion.

    Science.gov (United States)

    Ma, Xing; Katuri, Jaideep; Zeng, Yongfei; Zhao, Yanli; Sanchez, Samuel

    2015-10-01

    Surface-conductive Janus spherical motors are fabricated by wrapping silica particles with reduced graphene oxide capped with a thin Pt layer. These motors exhibit a 100% enhanced velocity as compared to standard SiO2 -Pt motors. Furthermore, the versatility of graphene may open up possibilities for a diverse range of applications from active drug delivery systems to water remediation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. CHF Enhancement by Surface Patterning based on Hydrodynamic Instability Model

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Han; Bang, In Cheol [UNIST, Ulsan (Korea, Republic of)

    2015-05-15

    If the power density of a device exceeds the CHF point, bubbles and vapor films will be covered on the whole heater surface. Because vapor films have much lower heat transfer capabilities compared to the liquid layer, the temperature of the heater surface will increase rapidly, and the device could be damaged due to the heater burnout. Therefore, the prediction and the enhancement of the CHF are essential to maximizing the efficient heat removal region. Numerous studies have been conducted to describe the CHF phenomenon, such as hydrodynamic instability theory, macrolayer dryout theory, hot/dry spot theory, and bubble interaction theory. The hydrodynamic instability model, proposed by Zuber, is the predominant CHF model that Helmholtz instability attributed to the CHF. Zuber assumed that the Rayleigh-Taylor (RT) instability wavelength is related to the Helmholtz wavelength. Lienhard and Dhir proposed a CHF model that Helmholtz instability wavelength is equal to the most dangerous RT wavelength. In addition, they showed the heater size effect using various heater surfaces. Lu et al. proposed a modified hydrodynamic theory that the Helmholtz instability was assumed to be the heater size and the area of the vapor column was used as a fitting factor. The modified hydrodynamic theories were based on the change of Helmholtz wavelength related to the RT instability wavelength. In the present study, the change of the RT instability wavelength, based on the heater surface modification, was conducted to show the CHF enhancement based on the heater surface patterning in a plate pool boiling. Sapphire glass was used as a base heater substrate, and the Pt film was used as a heating source. The patterning surface was based on the change of RT instability wavelength. In the present work the study of the CHF was conducted using bare Pt and patterned heating surfaces.

  11. Reactive surface organometallic complexes observed using dynamic nuclear polarization surface enhanced NMR spectroscopy

    KAUST Repository

    Pump, Eva

    2016-08-15

    Dynamic Nuclear Polarization Surface Enhanced NMR Spectroscopy (DNP SENS) is an emerging technique that allows access to high-sensitivity NMR spectra from surfaces. However, DNP SENS usually requires the use of radicals as an exogenous source of polarization, which has so far limited applications for organometallic surface species to those that do not react with the radicals. Here we show that reactive surface species can be studied if they are immobilized inside porous materials with suitably small windows, and if bulky nitroxide bi-radicals (here TEKPol) are used as the polarization source and which cannot enter the pores. The method is demonstrated by obtaining significant DNP enhancements from highly reactive complelxes [(equivalent to Si-O-)W(Me)(5)] supported on MCM-41, and effects of pore size (6.0, 3.0 and 2.5 nm) on the performance are discussed.

  12. Technology Survey for Enhancement of Chemical Biological Radiological and Nuclear Respiratory Protection

    National Research Council Canada - National Science Library

    Richardson, Aaron W; Hofacre, Kent C; Gardner, Paul D

    2008-01-01

    A technology survey was conducted to identify enhancement technologies that offer the most promise for significant advancements in chemical, biological, radiological, and nuclear individual respiratory protection...

  13. Development of exosome surface display technology in living human cells.

    Science.gov (United States)

    Stickney, Zachary; Losacco, Joseph; McDevitt, Sophie; Zhang, Zhiwen; Lu, Biao

    2016-03-25

    Surface display technology is an emerging key player in presenting functional proteins for targeted drug delivery and therapy. Although a number of technologies exist, a desirable mammalian surface display system is lacking. Exosomes are extracellular vesicles that facilitate cell-cell communication and can be engineered as nano-shuttles for cell-specific delivery. In this study, we report the development of a novel exosome surface display technology by exploiting mammalian cell secreted nano-vesicles and their trans-membrane protein tetraspanins. By constructing a set of fluorescent reporters for both the inner and outer surface display on exosomes at two selected sites of tetraspanins, we demonstrated the successful exosomal display via gene transfection and monitoring fluorescence in vivo. We subsequently validated our system by demonstrating the expected intracellular partitioning of reporter protein into sub-cellular compartments and secretion of exosomes from human HEK293 cells. Lastly, we established the stable engineered cells to harness the ability of this robust system for continuous production, secretion, and uptake of displayed exosomes with minimal impact on human cell biology. In sum, our work paved the way for potential applications of exosome, including exosome tracking and imaging, targeted drug delivery, as well as exosome-mediated vaccine and therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Development of exosome surface display technology in living human cells

    Energy Technology Data Exchange (ETDEWEB)

    Stickney, Zachary, E-mail: zstickney@scu.edu; Losacco, Joseph, E-mail: jlosacco@scu.edu; McDevitt, Sophie, E-mail: smmcdevitt@scu.edu; Zhang, Zhiwen, E-mail: zzhang@scu.edu; Lu, Biao, E-mail: blu2@scu.edu

    2016-03-25

    Surface display technology is an emerging key player in presenting functional proteins for targeted drug delivery and therapy. Although a number of technologies exist, a desirable mammalian surface display system is lacking. Exosomes are extracellular vesicles that facilitate cell–cell communication and can be engineered as nano-shuttles for cell-specific delivery. In this study, we report the development of a novel exosome surface display technology by exploiting mammalian cell secreted nano-vesicles and their trans-membrane protein tetraspanins. By constructing a set of fluorescent reporters for both the inner and outer surface display on exosomes at two selected sites of tetraspanins, we demonstrated the successful exosomal display via gene transfection and monitoring fluorescence in vivo. We subsequently validated our system by demonstrating the expected intracellular partitioning of reporter protein into sub-cellular compartments and secretion of exosomes from human HEK293 cells. Lastly, we established the stable engineered cells to harness the ability of this robust system for continuous production, secretion, and uptake of displayed exosomes with minimal impact on human cell biology. In sum, our work paved the way for potential applications of exosome, including exosome tracking and imaging, targeted drug delivery, as well as exosome-mediated vaccine and therapy.

  15. Enhanced vibrations at surfaces with back-bonds nearly parallel to the surface

    Energy Technology Data Exchange (ETDEWEB)

    Van Hove, M.A.

    2004-03-16

    It has been discovered that several very different surfaces exhibit a common property: unusually large vibration amplitudes of the outermost atoms, well beyond the enhancement normally expected at typical clean surfaces. These special surfaces are: ice H2O(0001), alpha-Al2O3(0001), alpha-Ga(010) and Si(111)-(2x1). The root-mean-square vibration amplitudes in these surfaces are at least double the bulk values. The common cause that may explain these vibration amplitudes is that the surface atoms (or molecules in the case of ice) only have back-bonds that are nearly parallel to the surface. In this geometry, vibrations, especially perpendicular to the surface, involve primarily bond bending rather than bond stretching/compression: since bond bending is relatively soft, the corresponding vibration modes can have larger amplitudes. It is suggested that theory examine and confirm this cause of enhanced surface vibration amplitudes, and explore its implication for other phenomena such as adsorption and catalysis.

  16. Surface plasmon enhanced interfacial electron transfer and resonance Raman, surface-enhanced resonance Raman studies of cytochrome C mutants

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Junwei [Iowa State Univ., Ames, IA (United States)

    1999-11-08

    Surface plasmon resonance was utilized to enhance the electron transfer at silver/solution interfaces. Photoelectrochemical reductions of nitrite, nitrate, and CO2 were studied on electrochemically roughened silver electrode surfaces. The dependence of the photocurrent on photon energy, applied potential and concentration of nitrite demonstrates that the photoelectrochemical reduction proceeds via photoemission process followed by the capture of hydrated electrons. The excitation of plasmon resonances in nanosized metal structures resulted in the enhancement of the photoemission process. In the case of photoelectrocatalytic reduction of CO2, large photoelectrocatalytic effect for the reduction of CO2 was observed in the presence of surface adsorbed methylviologen, which functions as a mediator for the photoexcited electron transfer from silver metal to CO2 in solution. Photoinduced reduction of microperoxidase-11 adsorbed on roughened silver electrode was also observed and attributed to the direct photoejection of free electrons of silver metal. Surface plasmon assisted electron transfer at nanostructured silver particle surfaces was further determined by EPR method.

  17. Enhancing Surface Plasmon Resonance Detection Using Nanostructured Au Chips

    Science.gov (United States)

    Indutnyi, Ivan; Ushenin, Yuriy; Hegemann, Dirk; Vandenbossche, Marianne; Myn'ko, Victor; Lukaniuk, Mariia; Shepeliavyi, Petro; Korchovyi, Andrii; Khrystosenko, Roman

    2016-12-01

    The increase of the sensitivity of surface plasmon resonance (SPR) refractometers was studied experimentally by forming a periodic relief in the form of a grating with submicron period on the surface of the Au-coated chip. Periodic reliefs of different depths and spatial frequency were formed on the Au film surface using interference lithography and vacuum chalcogenide photoresists. Spatial frequencies of the grating were selected close to the conditions of Bragg reflection of plasmons for the working wavelength of the SPR refractometer and the used environment (solution of glycerol in water). It was found that the degree of refractometer sensitivity enhancement and the value of the interval of environment refractive index variation, Δ n, in which this enhancement is observed, depend on the depth of the grating relief. By increasing the depth of relief from 13.5 ± 2 nm to 21.0 ± 2 nm, Δ n decreased from 0.009 to 0.0031, whereas sensitivity increased from 110 deg./RIU (refractive index unit) for a standard chip up to 264 and 484 deg./RIU for the nanostructured chips, respectively. Finally, it was shown that the working range of the sensor can be adjusted to the refractive index of the studied environment by changing the spatial frequency of the grating, by modification of the chip surface or by rotation of the chip.

  18. Enhanced water repellency of surfaces coated with multiscale carbon structures

    Science.gov (United States)

    Marchalot, Julien; Ramos, Stella. M. M.; Pirat, Christophe; Journet, Catherine

    2018-01-01

    Low cost and well characterized superhydrophobic surfaces are frequently required for industrial applications. Materials are commonly structured at the micro or nano scale. Surfaces decorated with nanotube derivatives synthesized by plasma enhanced chemical vapor deposition (PECVD) are of particular interest, since suitable modifications in the growth parameters can lead to numerous designs. In this article, we present surfaces that are selected for their specific wetting features with patterns ranging from dense forests to jungles with concave (re-entrant) surface such as flake-like multiscale roughness. Once these surfaces are functionalized adequately, their wetting properties are investigated. Their ability to sustain a superhydrophobic state for sessile water drops is examined. Finally, we propose a design to achieve a robust so-called ;Fakir; state, even for micrometer-sized drops, whereas with classic nanotubes forests it is not achievable. Thus, the drop remains on the apex of the protrusions with a high contact angle and a low contact angle hysteresis, while the surface features demonstrate good mechanical resistance against capillary forces.

  19. Surface Modification on Acoustic Wave Biosensors for Enhanced Specificity

    Directory of Open Access Journals (Sweden)

    Nathan D. Gallant

    2012-09-01

    Full Text Available Changes in mass loading on the surface of acoustic biosensors result in output frequency shifts which provide precise measurements of analytes. Therefore, to detect a particular biomarker, the sensor delay path must be judiciously designed to maximize sensitivity and specificity. B-cell lymphoma 2 protein (Bcl-2 found in urine is under investigation as a biomarker for non-invasive early detection of ovarian cancer. In this study, surface chemistry and biofunctionalization approaches were evaluated for their effectiveness in presenting antibodies for Bcl-2 capture while minimizing non-specific protein adsorption. The optimal combination of sequentially adsorbing protein A/G, anti-Bcl-2 IgG and Pluronic F127 onto a hydrophobic surface provided the greatest signal-to-noise ratio and enabled the reliable detection of Bcl-2 concentrations below that previously identified for early stage ovarian cancer as characterized by a modified ELISA method. Finally, the optimal surface modification was applied to a prototype acoustic device and the frequency shift for a range of Bcl-2 concentration was quantified to demonstrate the effectiveness in surface acoustic wave (SAW-based detection applications. The surface functionalization approaches demonstrated here to specifically and sensitively detect Bcl-2 in a working ultrasonic MEMS biosensor prototype can easily be modified to detect additional biomarkers and enhance other acoustic biosensors.

  20. Surface-Enhanced Raman Scattering in Molecular Junctions.

    Science.gov (United States)

    Iwane, Madoka; Fujii, Shintaro; Kiguchi, Manabu

    2017-08-18

    Surface-enhanced Raman scattering (SERS) is a surface-sensitive vibrational spectroscopy that allows Raman spectroscopy on a single molecular scale. Here, we present a review of SERS from molecular junctions, in which a single molecule or molecules are made to have contact from the top to the bottom of metal surfaces. The molecular junctions are nice platforms for SERS as well as transport measurement. Electronic characterization based on the transport measurements of molecular junctions has been extensively studied for the development of miniaturized electronic devices. Simultaneous SERS and transport measurement of the molecular junctions allow both structural (geometrical) and electronic information on the single molecule scale. The improvement of SERS measurement on molecular junctions open the door toward new nanoscience and nanotechnology in molecular electronics.

  1. Technology strategy for enhanced recovery; Technology Target Areas; TTA3 - enhanced recovery

    Energy Technology Data Exchange (ETDEWEB)

    2007-07-01

    The Norwegian Continental Shelf (NCS) is facing new challenges in reserve replacement and improved recovery in order to maintain the overall oil production rate from the area. A new target for an increase in oil reserves of 800 million Sm3 of oil (5 billion barrels) by year 2015 has been set by NPD. This is an ambitious goal considering several of the large fields are on a steep decline, and most of the recent discoveries are relatively small. A significant part of these increased reserves will have to come from fields currently on production, from reservoir areas that have been partly or fully swept, and it is therefore evident that Enhanced Oil Recovery (EOR) methods have to play a key role in achieving this target. EOR methods can be divided into gas based EOR methods and water based EOR methods. Thermal methods are not considered applicable on the NCS due to the relatively light oils present, and the depth of the reservoirs. Gas Based EOR; Water Based EOR; CO{sub 2} injection; Surfactants; Air injection; Polymer; Nitrogen injection; Alkaline; Flue gas injection; Polymer gels; WAG; MEOR; FAWAG. The former OG21 strategy document gave high priority to Water Alternating Gas (WAG) methods and CO{sub 2} injection for enhanced recovery. A lot of research and development and evaluation projects on CO{sub 2} injection were launched and are on-going, most of these are being CO{sub 2} WAG studies. The main challenge now in order to realize CO{sub 2} injection on the NCS is on CO{sub 2} availability and transport. It is also believed that increasing gas prices will limit the availability of hydrocarbon gas for injection purposes in the future. There is, however, a clear need for developing alternative cost efficient EOR methods that can improve the sweep efficiency significantly. Since a majority of the fields on the NCS are being produced under water flooding (or WAG), methods that can improve the water flooding efficiency by chemical additives are of special interest and

  2. Surface Acoustic Wave (SAW-Enhanced Chemical Functionalization of Gold Films

    Directory of Open Access Journals (Sweden)

    Gina Greco

    2017-10-01

    Full Text Available Surface chemical and biochemical functionalization is a fundamental process that is widely applied in many fields to add new functions, features, or capabilities to a material’s surface. Here, we demonstrate that surface acoustic waves (SAWs can enhance the chemical functionalization of gold films. This is shown by using an integrated biochip composed by a microfluidic channel coupled to a surface plasmon resonance (SPR readout system and by monitoring the adhesion of biotin-thiol on the gold SPR areas in different conditions. In the case of SAW-induced streaming, the functionalization efficiency is improved ≈ 5 times with respect to the case without SAWs. The technology here proposed can be easily applied to a wide variety of biological systems (e.g., proteins, nucleic acids and devices (e.g., sensors, devices for cell cultures.

  3. Surface-enhanced gallium arsenide photonic resonator with a quality factor of six million

    CERN Document Server

    Guha, Biswarup; Cadiz, Fabian; Morgenroth, Laurence; Ulin, Vladimir; Berkovitz, Vladimir; Lemaître, Aristide; Gomez, Carmen; Amo, Alberto; Combrié, Sylvian; Gérard, Bruno; Leo, Giuseppe; Favero, Ivan

    2016-01-01

    Gallium Arsenide and related compound semiconductors lie at the heart of optoelectronics and integrated laser technologies. Shaped at the micro and nano-scale, they allow strong interaction with quantum dots and quantum wells, and promise to result in stunning devices. However gallium arsenide optical structures presently exhibit lower performances than their silicon-based counterparts, notably in nanophotonics where the surface plays a chief role. Here we report on advanced surface control of miniature gallium arsenide optical resonators, using two distinct techniques that produce permanent results. One leads to extend the lifetime of free-carriers and enhance luminescence, while the other strongly reduces surface absorption originating from mid-gap states and enables ultra-low optical dissipation devices. With such surface control, the quality factor of wavelength-sized optical disk resonators is observed to rise up to six million at telecom wavelength, greatly surpassing previous realizations and opening n...

  4. Comparison of the effectiveness of different antimicrobial surface technologies

    Directory of Open Access Journals (Sweden)

    Buhl Sebastian

    2017-09-01

    Full Text Available The risk of infection via microbiologically contaminated surfaces has already been demonstrated by other publications. In this work two different antibacterial surface technologies transition metalloacids (AMiSTec and TiO2/AgNO3 (Health Complete were compared regarding feasibility as well as their advantages and disadvantages. The examination of the antimicrobial activity was assessed according to the JIS Z 2801. We could demonstrate that all of our tested samples showed a strong antimicrobial activity (>log 3 germ reduction in the JIS experiments. Furthermore this strong antibacterial effect could be shown already after <30min incubation and at low light intensity (approx. 300 Lux for the TiO2/AgNO3 samples. Both technologies provide a high potential for an improved infection control for example in a high risk environment like operation rooms or intensive care units.

  5. International Symposium on Interfacial Joining and Surface Technology (IJST2013)

    Science.gov (United States)

    Takahashi, Yasuo

    2014-08-01

    Interfacial joining (bonding) is a widely accepted welding process and one of the environmentally benign technologies used in industrial production. As the bonding temperature is lower than the melting point of the parent materials, melting of the latter is kept to a minimum. The process can be based on diffusion bonding, pressure welding, friction welding, ultrasonic bonding, or brazing-soldering, all of which offer many advantages over fusion welding. In addition, surface technologies such as surface modification, spraying, coating, plating, and thin-film formation are necessary for advanced manufacturing, fabrication, and electronics packaging. Together, interfacial joining and surface technology (IJST) will continue to be used in various industrial fields because IJST is a very significant form of environmentally conscious materials processing. The international symposium of IJST 2013 was held at Icho Kaikan, Osaka University, Japan from 27-29 November, 2013. A total of 138 participants came from around the world to attend 56 oral presentations and 36 posters presented at the symposium, and to discuss the latest research and developments on interfacial joining and surface technologies. This symposium was also held to commemorate the 30th anniversary of the Technical Commission on Interfacial Joining of the Japan Welding Society. On behalf of the chair of the symposium, it is my great pleasure to present this volume of IOP Conference Series: Materials Science and Engineering (MSE). Among the presentations, 43 papers are published here, and I believe all of the papers have provided the welding community with much useful information. I would like to thank the authors for their enthusiastic and excellent contributions. Finally, I would like to thank all members of the committees, secretariats, participants, and everyone who contributed to this symposium through their support and invaluable effort for the success of IJST 2013. Yasuo Takahashi Chair of IJST 2013

  6. Performance Enhancement of the Patch Antennas Applying Micromachining Technology

    Directory of Open Access Journals (Sweden)

    Mohamed N. Azermanesh

    2007-09-01

    Full Text Available This paper reports on the application of micromachining technology for performance enhancement of two types of compact antennas which are becoming a common practice in microsystems. Shorted patch antennas (SPA and folded shorted patch antennas operating in the 5-6 GHz ISM band, with intended application in short-range wireless communications, are considered. The electrical length of antennas are modified by etching the substrate of the antennas, thus providing a new degree of freedom to control the antenna operating properties, which is the main novelty of our work. The gain and bandwidth of the antennas are increased by increasing the etching depth. However, etching the substrate affects the operating frequency as well. To keep the operating frequency at a pre-specified value, the dimension of the antennas must be increased by deepening the etching depth. Therefore, a trade off between the performance enhancement of the antennas and the dimensional enlargement is required.

  7. Surface Plasmons and Surface Enhanced Raman Spectra of Aggregated and Alloyed Gold-Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Y. Fleger

    2009-01-01

    Full Text Available Effects of size, morphology, and composition of gold and silver nanoparticles on surface plasmon resonance (SPR and surface enhanced Raman spectroscopy (SERS are studied with the purpose of optimizing SERS substrates. Various gold and silver films made by evaporation and subsequent annealing give different morphologies and compositions of nanoparticles and thus different position of the SPR peak. SERS measurements of 4-mercaptobenzoic acid obtained from these films reveal that the proximity of the SPR peak to the exciting laser wavelength is not the only factor leading to the highest Raman enhancement. Silver nanoparticles evaporated on top of larger gold nanoparticles show higher SERS than gold-silver alloyed nanoparticles, in spite of the fact that the SPR peak of alloyed nanoparticles is narrower and closer to the excitation wavelength. The highest Raman enhancement was obtained for substrates with a two-peak particle size distribution for excitation wavelengths close to the SPR.

  8. Smooth Surfaces: A review of current and planned smooth surface technologies for fouling resistance in boiler

    Energy Technology Data Exchange (ETDEWEB)

    Corkery, Robert; Baefver, Linda; Davidsson, Kent; Feiler, Adam

    2012-02-15

    Here we have described the basics of boilers, fuels, combustion, flue gas composition and mechanisms of deposition. We have reviewed coating technologies for boiler tubes, including their materials compositions, nano structures and performances. The surface forces in boilers, in particular those relevant to formation of unwanted deposits in boilers have also been reviewed, and some comparative calculations have been included to indicate the procedures needed for further study. Finally practical recommendations on the important considerations in minimizing deposition on boiler surfaces are made

  9. The surface chemistry of rutile in technologically relevant environments

    Science.gov (United States)

    Song, Anqi

    The surface science of titanium dioxide, TiO2, has attracted great amount of attention due to its high profile applications. This dissertation shows the development of well-controlled rutile (110) surfaces that provide a platform for studying the chemical and photochemical reactivity of rutile in technologically relevant environments, including air and solutions. Near-perfect rutile (110) surfaces characterized by atomically flat terraces and straight steps were produced using basic peroxide solutions. The reaction produced straight steps with a different orientation, different structure, and different reactivity from those prepared in ultrahigh vacuum. The morphology was explained by a site-specific model of rutile (110) etching based on metal oxo coordination chemistry. This work shows that one of the important roles of peroxo ligands in etching and growth reactions is to destabilize neighboring bonds and increase their lability. The peroxo ligands add a degree of reversibility to the growth reaction, leading to the formation of well-ordered crystals. In addition, this near-perfect rutile (110) surface is an ideal starting point for studying surface chemistry of rutile in technologically relevant environments. Under ambient conditions atmospheric CO2 reacted with adsorbed H2O and produced a self-assembled monolayer of HCO 3 on rutile (110) surfaces. The monolayer was formed on the near-perfect rutile surfaces prepared by basic peroxide etching, indicating that surface defects, such as Ti interstitials and O vacancies, were not required. DFT calculations suggested that the nanoscale water film adsorbed on the surface solvated the adsorbates and changed the reaction energetics. The HCO 3 monolayer was very stable, even in vacuum, which was a result of the strong bidentate bonding of HCO3. The formation of the strongly bound bicarbonate monolayer suggests that HCO3, instead of CO 2, plays a key role in the photoreduction of CO2. A high-quality, self

  10. Enhancement of Light via Surface Plasmon Coupling in the Visible

    Science.gov (United States)

    Ray, Emily A.

    The incidence of light with momentum components outside the light cone on the surface of a negative permittivity material results in the excitation of a surface plasmon polariton and the enhancement of the incident signal when there is momentum and energy conservation. This process has an impact across many fields including imaging, optical computing, signaling, and photovoltaic devices, among others. I examine the role and tunability of light-surface plasmon interactions in several applications. I demonstrate a tuned metamaterial grating system that allows the signal from evanescent waves to be detected in the far field in the visible regime. I fabricate a metamaterial that is tuned to support surface plasmons that couple to visible light across a wide range of wavelengths. I characterize the plasmonic response through a simple technique wherein a the reflection from a subwavelength grating on a metamaterial indicates surface plasmon coupling when its intensity dips. With this I demonstrate that the reflection trends match well with simulation, indicating that coupling of light to surface plasmons occurs at the expected crossing points. The strength of coupling (denoted by the drop in reflection) however, is less than expected. Transmission measurements reveal a depolarizing effect that accounts for the decrease in evanescent light enhancement by the surface plasmons and is due to the surface roughness at the interfaces between the metal and dielectric. I also use a tuned metamaterial perforated with a subwavelength array of circular apertures to exhibit extraordinary transmission in the visible. I compare the transmission of the metamaterial to that of a thin film of Ag with equivalent thickness that has fewer plasmon modes and a resonance position in the UV to find that for 400 nm, both thin films exhibit a transmission minimum at 650 nm. Both film spectra have plasmon-aided extraordinary transmission peaks where there is momentum and energy conservation between

  11. Enhanced perfume surface delivery to interfaces using surfactant surface multilayer structures.

    Science.gov (United States)

    Bradbury, Robert; Penfold, Jeffrey; Thomas, Robert K; Tucker, Ian M; Petkov, Jordan T; Jones, Craig

    2016-01-01

    Enhanced surface delivery and retention of perfumes at interfaces are the keys to their more effective and efficient deployment in a wide range of home and personal care related formulations. It has been previously demonstrated that the addition of multivalent counterions, notably Ca(2+), induces multilayer adsorption at the air-water interface for the anionic surfactant, sodium dodecyl-6-benzenesulfonate, LAS-6. Neutron reflectivity, NR, measurements are reported here which demonstrate that such surfactant surface multilayer structures are a potentially promising vehicle for enhanced delivery of perfumes to interfaces. The data show that the incorporation of the model perfumes, phenylethanol, PE, and linalool, LL, into the surface multilayer structure formed by LAS-6/Ca(2+) results in the surface structures being retained up to relatively high perfume mole fractions. Furthermore the amount of perfume at the surface is enhanced by at least an order of magnitude, compared to that co-adsorbed with a surfactant monolayer. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Surface-enhanced Raman spectroscopy of bacteria coated by silver

    Science.gov (United States)

    Efrima, Schlomo; Bronk, Burt V.; Czege, Jozsef

    1999-05-01

    We present a novel method to measure Raman spectra from whole bacteria cells by using Surface Enhanced Raman Scattering (SERS). We deposit a silver coat on Escherichia coli and Bacillus megaterium bacteria and measure strongly enhanced (greater than 400,000 fold) and highly reproducible Raman spectra. The spectra are rich but not overly congested, as the surface enhancement is selective to the precise chemical nature of the biochemical molecules, and their proximity to the silver particulate matter. The main bands we observe can be associated with peptides and polysaccharides in the cell- wall and its membrane. The spectra from E. coli (a Gram- negative bacterium) and B. megaterium (a Gram-positive bacterium) are similar in their general form, but differ in detail. The spectrum from a commercial yeast extract is vastly different. This approach can be extended to probe the internal chemical environment within bacteria and applied to the identification of micro-organisms also applied to studying other biochemical problems and phenomena, such as biomineralization, heavy metal toxicity, cell-wall structure and others.

  13. Enhanced microcontact printing of proteins on nanoporous silica surface

    Energy Technology Data Exchange (ETDEWEB)

    Blinka, Ellen; Hu Ye; Gopal, Ashwini; Hoshino, Kazunori; Lin, Kevin; Zhang, John X J [Department of Biomedical Engineering, University of Texas at Austin, Austin, TX 78758 (United States); Loeffler, Kathryn; Liu Xuewu; Ferrari, Mauro, E-mail: John.Zhang@engr.utexas.edu [Department of Nanomedicine and Biomedical Engineering, University of Texas Health Science Service, Houston, TX 77031 (United States)

    2010-10-15

    We demonstrate porous silica surface modification, combined with microcontact printing, as an effective method for enhanced protein patterning and adsorption on arbitrary surfaces. Compared to conventional chemical treatments, this approach offers scalability and long-term device stability without requiring complex chemical activation. Two chemical surface treatments using functionalization with the commonly used 3-aminopropyltriethoxysilane (APTES) and glutaraldehyde (GA) were compared with the nanoporous silica surface on the basis of protein adsorption. The deposited thickness and uniformity of porous silica films were evaluated for fluorescein isothiocyanate (FITC)-labeled rabbit immunoglobulin G (R-IgG) protein printed onto the substrates via patterned polydimethlysiloxane (PDMS) stamps. A more complete transfer of proteins was observed on porous silica substrates compared to chemically functionalized substrates. A comparison of different pore sizes (4-6 nm) and porous silica thicknesses (96-200 nm) indicates that porous silica with 4 nm diameter, 57% porosity and a thickness of 96 nm provided a suitable environment for complete transfer of R-IgG proteins. Both fluorescence microscopy and atomic force microscopy (AFM) were used for protein layer characterizations. A porous silica layer is biocompatible, providing a favorable transfer medium with minimal damage to the proteins. A patterned immunoassay microchip was developed to demonstrate the retained protein function after printing on nanoporous surfaces, which enables printable and robust immunoassay detection for point-of-care applications.

  14. Surface-Enhanced Raman Optical Data Storage system

    Science.gov (United States)

    Vo-Dinh, T.

    1994-06-28

    An improved Surface-Enhanced Raman Optical Data Storage System (SERODS) is disclosed. In the improved system, entities capable of existing in multiple reversible states are present on the storage device. Such entities result in changed Surface-Enhanced Raman Scattering (SERS) when localized state changes are effected in less than all of the entities. Therefore, by changing the state of entities in localized regions of a storage device, the SERS emissions in such regions will be changed. When a write-on device is controlled by a data signal, such a localized regions of changed SERS emissions will correspond to the data written on the device. The data may be read by illuminating the surface of the storage device with electromagnetic radiation of an appropriate frequency and detecting the corresponding SERS emissions. Data may be deleted by reversing the state changes of entities in regions where the data was initially written. In application, entities may be individual molecules which allows for the writing of data at the molecular level. A read/write/delete head utilizing near-field quantum techniques can provide for a write/read/delete device capable of effecting state changes in individual molecules, thus providing for the effective storage of data at the molecular level. 18 figures.

  15. Periodic array-based substrates for surface-enhanced infrared spectroscopy

    Science.gov (United States)

    Mayerhöfer, Thomas G.; Popp, Jürgen

    2018-01-01

    At the beginning of the 1980s, the first reports of surface-enhanced infrared spectroscopy (SEIRS) surfaced. Probably due to signal-enhancement factors of only 101 to 103, which are modest compared to those of surface-enhanced Raman spectroscopy (SERS), SEIRS did not reach the same significance up to date. However, taking the compared to Raman scattering much larger cross-sections of infrared absorptions and the enhancement factors together, SEIRS reaches about the same sensitivity for molecular species on a surface in terms of the cross-sections as SERS and, due to the complementary nature of both techniques, can valuably augment information gained by SERS. For the first 20 years since its discovery, SEIRS relied completely on metal island films, fabricated by either vapor or electrochemical deposition. The resulting films showed a strong variance concerning their structure, which was essentially random. Therefore, the increase in the corresponding signal-enhancement factors of these structures stagnated in the last years. In the very same years, however, the development of periodic array-based substrates helped SEIRS to gather momentum. This development was supported by technological progress concerning electromagnetic field solvers, which help to understand plasmonic properties and allow targeted design. In addition, the strong progress concerning modern fabrication methods allowed to implement these designs into practice. The aim of this contribution is to critically review the development of these engineered surfaces for SEIRS, to compare the different approaches with regard to their performance where possible, and report further gain of knowledge around and in relation to these structures.

  16. Periodic array-based substrates for surface-enhanced infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Mayerhöfer Thomas G.

    2018-01-01

    Full Text Available At the beginning of the 1980s, the first reports of surface-enhanced infrared spectroscopy (SEIRS surfaced. Probably due to signal-enhancement factors of only 101 to 103, which are modest compared to those of surface-enhanced Raman spectroscopy (SERS, SEIRS did not reach the same significance up to date. However, taking the compared to Raman scattering much larger cross-sections of infrared absorptions and the enhancement factors together, SEIRS reaches about the same sensitivity for molecular species on a surface in terms of the cross-sections as SERS and, due to the complementary nature of both techniques, can valuably augment information gained by SERS. For the first 20 years since its discovery, SEIRS relied completely on metal island films, fabricated by either vapor or electrochemical deposition. The resulting films showed a strong variance concerning their structure, which was essentially random. Therefore, the increase in the corresponding signal-enhancement factors of these structures stagnated in the last years. In the very same years, however, the development of periodic array-based substrates helped SEIRS to gather momentum. This development was supported by technological progress concerning electromagnetic field solvers, which help to understand plasmonic properties and allow targeted design. In addition, the strong progress concerning modern fabrication methods allowed to implement these designs into practice. The aim of this contribution is to critically review the development of these engineered surfaces for SEIRS, to compare the different approaches with regard to their performance where possible, and report further gain of knowledge around and in relation to these structures.

  17. Detection of volatile organic compounds using surface enhanced Raman scattering

    Energy Technology Data Exchange (ETDEWEB)

    Chang, A S; Maiti, A; Ileri, N; Bora, M; Larson, C C; Britten, J A; Bond, T C

    2012-03-22

    The authors present the detection of volatile organic compounds directly in their vapor phase by surface-enhanced Raman scattering (SERS) substrates based on lithographically-defined two-dimensional rectangular array of nanopillars. The type of nanopillars is known as the tapered pillars. For the tapered pillars, SERS enhancement arises from the nanofocusing effect due to the sharp tip on top. SERS experiments were carried out on these substrates using various concentrations of toluene vapor. The results show that SERS signal from a toluene vapor concentration of ppm level can be achieved, and the toluene vapor can be detected within minutes of exposing the SERS substrate to the vapor. A simple adsorption model is developed which gives results matching the experimental data. The results also show promising potential for the use of these substrates in environmental monitoring of gases and vapors.

  18. Novel routes to electromagnetic enhancement and its characterisation in surface- and tip-enhanced Raman scattering.

    Science.gov (United States)

    Dawson, P; Frey, D; Kalathingal, V; Mehfuz, R; Mitra, J

    2017-09-08

    Quantitative understanding of the electromagnetic component in enhanced Raman spectroscopy is often difficult to achieve on account of the complex substrate structures utilised. We therefore turn to two structurally simple systems amenable to detailed modelling. The first is tip-enhanced Raman scattering under electron scanning tunnelling microscopy control (STM-TERS) where, appealing to understanding developed in the context of photon emission from STM, it is argued that the localised surface plasmon modes driving the Raman enhancement exist in the visible and near-infrared regime only by virtue of significant modification to the optical properties of the tip and sample metals (gold here). This is due to the strong dc field-induced (∼10(9) V m(-1)) non-linear corrections to the dielectric function of gold via the third order susceptibility term in the polarisation. Also, sub-5 nm spatial resolution is shown in the modelling. Secondly, we suggest a novel deployment of hybrid plasmonic waveguide modes in surface enhanced Raman scattering (HPWG-SERS). This delivers strong confinement of electromagnetic energy in a ∼10 nm oxide 'gap' between a high-index dielectric material of nanoscale width (a GaAs nanorod and a 100 nm Si slab are considered here) and a metal, yielding a monotonic variation in the Raman enhancement factor as a function of wavelength with no long-wavelength cut-off, both features that contrast with STM-TERS.

  19. Single Molecule Detection Using Surface-Enhanced Raman Scattering (SERS)

    Science.gov (United States)

    Kneipp, Katrin; Wang, Yang; Kneipp, Harald; Perelman, Lev T.; Itzkan, Irving; Dasari, Ramachandra R.; Feld, Michael S.

    1997-03-01

    By exploiting the extremely large effective cross sections ( 10-17-10-16 cm2/molecule) available from surface-enhanced Raman scattering (SERS), we achieved the first observation of single molecule Raman scattering. Measured spectra of a single crystal violet molecule in aqueous colloidal silver solution using one second collection time and about 2×105 W/cm2 nonresonant near-infrared excitation show a clear ``fingerprint'' of its Raman features between 700 and 1700 cm-1. Spectra observed in a time sequence for an average of 0.6 dye molecule in the probed volume exhibited the expected Poisson distribution for actually measuring 0, 1, 2, or 3 molecules.

  20. Membranes with Surface-Enhanced Antifouling Properties for Water Purification

    Directory of Open Access Journals (Sweden)

    Nima Shahkaramipour

    2017-03-01

    Full Text Available Membrane technology has emerged as an attractive approach for water purification, while mitigation of fouling is key to lower membrane operating costs. This article reviews various materials with antifouling properties that can be coated or grafted onto the membrane surface to improve the antifouling properties of the membranes and thus, retain high water permeance. These materials can be separated into three categories, hydrophilic materials, such as poly(ethylene glycol, polydopamine and zwitterions, hydrophobic materials, such as fluoropolymers, and amphiphilic materials. The states of water in these materials and the mechanisms for the antifouling properties are discussed. The corresponding approaches to coat or graft these materials on the membrane surface are reviewed, and the materials with promising performance are highlighted.

  1. Membranes with Surface-Enhanced Antifouling Properties for Water Purification

    Science.gov (United States)

    Shahkaramipour, Nima; Tran, Thien N.; Ramanan, Sankara; Lin, Haiqing

    2017-01-01

    Membrane technology has emerged as an attractive approach for water purification, while mitigation of fouling is key to lower membrane operating costs. This article reviews various materials with antifouling properties that can be coated or grafted onto the membrane surface to improve the antifouling properties of the membranes and thus, retain high water permeance. These materials can be separated into three categories, hydrophilic materials, such as poly(ethylene glycol), polydopamine and zwitterions, hydrophobic materials, such as fluoropolymers, and amphiphilic materials. The states of water in these materials and the mechanisms for the antifouling properties are discussed. The corresponding approaches to coat or graft these materials on the membrane surface are reviewed, and the materials with promising performance are highlighted. PMID:28273869

  2. Nanoscale patterning, macroscopic reconstruction, and enhanced surface stress by organic adsorption on vicinal surfaces

    Science.gov (United States)

    Pollinger, Florian; Schmitt, Stefan; Sander, Dirk; Tian, Zhen; Kirschner, Jürgen; Vrdoljak, Pavo; Stadler, Christoph; Maier, Florian; Marchetto, Helder; Schmidt, Thomas; Schöll, Achim; Umbach, Eberhard

    2017-01-01

    Self-organization is a promising method within the framework of bottom-up architectures to generate nanostructures in an efficient way. The present work demonstrates that self-organization on the length scale of a few to several tens of nanometers can be achieved by a proper combination of a large (organic) molecule and a vicinal metal surface if the local bonding of the molecule on steps is significantly stronger than that on low-index surfaces. In this case thermal annealing may lead to large mass transport of the subjacent substrate atoms such that nanometer-wide and micrometer-long molecular stripes or other patterns are being formed on high-index planes. The formation of these patterns can be controlled by the initial surface orientation and adsorbate coverage. The patterns arrange self-organized in regular arrays by repulsive mechanical interactions over long distances accompanied by a significant enhancement of surface stress. We demonstrate this effect using the planar organic molecule PTCDA as adsorbate and Ag(10 8 7) and Ag(775) surfaces as substrate. The patterns are directly observed by STM, the formation of vicinal surfaces is monitored by high-resolution electron diffraction, the microscopic surface morphology changes are followed by spectro-microscopy, and the macroscopic changes of surface stress are measured by a cantilever bending method. The in situ combination of these complementary techniques provides compelling evidence for elastic interaction and a significant stress contribution to long-range order and nanopattern formation.

  3. Spectrally enhanced image resolution of tooth enamel surfaces

    Science.gov (United States)

    Zhang, Liang; Nelson, Leonard Y.; Berg, Joel H.; Seibel, Eric J.

    2012-01-01

    Short-wavelength 405 nm laser illumination of surface dental enamel using an ultrathin scanning fiber endoscope (SFE) produced enhanced detail of dental topography. The surfaces of human extracted teeth and artificial erosions were imaged with 405 nm, 444 nm, 532 nm, or 635 nm illumination lasers. The obtained images were then processed offline to compensate for any differences in the illumination beam diameters between the different lasers. Scattering and absorption coefficients for a Monte Carlo model of light propagation in dental enamel for 405 nm were scaled from published data at 532 nm and 633 nm. The value of the scattering coefficient used in the model was scaled from the coefficients at 532 nm and 633 nm by the inverse third power of wavelength. Simulations showed that the penetration depth of short-wavelength illumination is localized close to the enamel surface, while long-wavelength illumination travels much further and is backscattered from greater depths. Therefore, images obtained using short wavelength laser are not contaminated by the superposition of light reflected from enamel tissue at greater depths. Hence, the SFE with short-wavelength illumination may make it possible to visualize surface manifestations of phenomena such as demineralization, thus better aiding the clinician in the detection of early caries.

  4. Detection of explosive vapour using surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Fang, X.; Ahmad, S. R.

    2009-11-01

    A commercially available nano-structured gold substrate was used for activating surface-enhanced Raman scattering (SERS). Raman spectra of the vapour of explosive material, triacetonetriperoxide (TATP), at trace concentrations produced from adsorbed molecules on such surfaces have been studied. Prominent Raman lines of the explosive molecular species were recorded at a sample temperature of ˜35°C, which is near to human body temperature. For this study, the concentration of the adsorbed TATP molecules on the nano-structured surface was varied by heating the sample to different temperatures and exposing the substrate to the sample vapour for different lengths of time. The intensities of the Raman lines have been found to increase with the increase in temperature and also with the increase in the duration of exposure for a fixed temperature. However, as expected, the Raman intensities have been found to saturate at higher temperatures and longer exposures. These saturation effects of the strengths of the Raman lines in the SERS of TATP vapour have been investigated in this paper. The results indicate that the optimisation for vapour deposition on the surface could be a crucial factor for any quantitative estimate of the concentration of the molecular species adsorbed on the nano-structured substrates.

  5. Enhanced Geothermal Systems (EGS) well construction technology evaluation report.

    Energy Technology Data Exchange (ETDEWEB)

    Capuano, Louis, Jr. (Thermasource Inc.); Huh, Michael; Swanson, Robert (Thermasource Inc.); Raymond, David Wayne; Finger, John Travis; Mansure, Arthur James; Polsky, Yarom; Knudsen, Steven Dell

    2008-12-01

    Electricity production from geothermal resources is currently based on the exploitation of hydrothermal reservoirs. Hydrothermal reservoirs possess three ingredients critical to present day commercial extraction of subsurface heat: high temperature, in-situ fluid and high permeability. Relative to the total subsurface heat resource available, hydrothermal resources are geographically and quantitatively limited. A 2006 DOE sponsored study led by MIT entitled 'The Future of Geothermal Energy' estimates the thermal resource underlying the United States at depths between 3 km and 10 km to be on the order of 14 million EJ. For comparison purposes, total U.S. energy consumption in 2005 was 100 EJ. The overwhelming majority of this resource is present in geological formations which lack either in-situ fluid, permeability or both. Economical extraction of the heat in non-hydrothermal situations is termed Enhanced or Engineered Geothermal Systems (EGS). The technologies and processes required for EGS are currently in a developmental stage. Accessing the vast thermal resource between 3 km and 10 km in particular requires a significant extension of current hydrothermal practice, where wells rarely reach 3 km in depth. This report provides an assessment of well construction technology for EGS with two primary objectives: (1) Determining the ability of existing technologies to develop EGS wells. (2) Identifying critical well construction research lines and development technologies that are likely to enhance prospects for EGS viability and improve overall economics. Towards these ends, a methodology is followed in which a case study is developed to systematically and quantitatively evaluate EGS well construction technology needs. A baseline EGS well specification is first formulated. The steps, tasks and tools involved in the construction of this prospective baseline EGS well are then explicitly defined by a geothermal drilling contractor in terms of sequence, time and

  6. TELMA: Technology-enhanced learning environment for minimally invasive surgery.

    Science.gov (United States)

    Sánchez-González, Patricia; Burgos, Daniel; Oropesa, Ignacio; Romero, Vicente; Albacete, Antonio; Sánchez-Peralta, Luisa F; Noguera, José F; Sánchez-Margallo, Francisco M; Gómez, Enrique J

    2013-06-01

    Cognitive skills training for minimally invasive surgery has traditionally relied upon diverse tools, such as seminars or lectures. Web technologies for e-learning have been adopted to provide ubiquitous training and serve as structured repositories for the vast amount of laparoscopic video sources available. However, these technologies fail to offer such features as formative and summative evaluation, guided learning, or collaborative interaction between users. The "TELMA" environment is presented as a new technology-enhanced learning platform that increases the user's experience using a four-pillared architecture: (1) an authoring tool for the creation of didactic contents; (2) a learning content and knowledge management system that incorporates a modular and scalable system to capture, catalogue, search, and retrieve multimedia content; (3) an evaluation module that provides learning feedback to users; and (4) a professional network for collaborative learning between users. Face validation of the environment and the authoring tool are presented. Face validation of TELMA reveals the positive perception of surgeons regarding the implementation of TELMA and their willingness to use it as a cognitive skills training tool. Preliminary validation data also reflect the importance of providing an easy-to-use, functional authoring tool to create didactic content. The TELMA environment is currently installed and used at the Jesús Usón Minimally Invasive Surgery Centre and several other Spanish hospitals. Face validation results ascertain the acceptance and usefulness of this new minimally invasive surgery training environment. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Assessing the Applicability of 3D Holographic Technology as an Enhanced Technology for Distance Learning

    Directory of Open Access Journals (Sweden)

    Pradeep Kalansooriya

    2015-08-01

    Full Text Available Distance learning has provided an excellent platform for students in geographically remote locations while enabling them to learn at their own pace and convenience. A number of technologies are currently being utilized to conceptualize, design, enhance and foster distance learning. Teleconferences, electronic field trips, podcasts, webinars, video conferencing and online courses are among such technologies used in providing distance learning opportunities. However limitations in those existing technologies have affected to the increase of distance learners dropout rates. As an attempt to overcome the limitations in the currently adopted distance learning practices, the study aims to utilize 3D Hologram Technology (3DHT in the Engineering discipline. 3D hologram facilitates live and life size 3D telepresence that can interact with remote audiences. A survey had been conducted, using Delphi Technique to gather data from the experts in the field to evaluate the potential of 3DHT over existing technologies. Results of the survey suggested that 3DHT as a good distance learning technology and have the potential of overcoming existing limitations. Lack of infrastructure, High initial cost of infrastructure and Lack of technical know how are the main encounters identified by the experts in the sample. It is expected to develop a classroom environment with 3DHT and to evaluate its effectiveness for the distance learning in the next stage of the study.

  8. Surface enhanced Raman scattering (SERS) fabrics for trace analysis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jun [National Engineering Laboratory for Advanced Yarn and Fabric Formation and Clean Production, Wuhan Textile University, Wuhan 430073 (China); Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education & College of Chemistry & Chemical Engineering, Hubei University, Wuhan 430062 (China); Zhou, Ji [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education & College of Chemistry & Chemical Engineering, Hubei University, Wuhan 430062 (China); Tang, Bin, E-mail: bin.tang@deakin.edu.au [National Engineering Laboratory for Advanced Yarn and Fabric Formation and Clean Production, Wuhan Textile University, Wuhan 430073 (China); Institute for Frontier Materials, Deakin University, Geelong, Victoria 3216 (Australia); Zeng, Tian; Li, Yaling [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education & College of Chemistry & Chemical Engineering, Hubei University, Wuhan 430062 (China); Li, Jingliang [Institute for Frontier Materials, Deakin University, Geelong, Victoria 3216 (Australia); Ye, Yong, E-mail: yeyong@hubu.edu.cn [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Ministry of Education & College of Chemistry & Chemical Engineering, Hubei University, Wuhan 430062 (China); Wang, Xungai [National Engineering Laboratory for Advanced Yarn and Fabric Formation and Clean Production, Wuhan Textile University, Wuhan 430073 (China); Institute for Frontier Materials, Deakin University, Geelong, Victoria 3216 (Australia)

    2016-11-15

    Highlights: • Gold nanoparticles are in-situ synthesized on silk fabrics by heating. • Flexible silk fabrics with gold nanoparticles are used for surface-enhanced Raman scattering (SERS). • SERS activities of silk fabrics with different gold contents are investigated. - Abstract: Flexible SERS active substrates were prepared by modification of silk fabrics with gold nanoparticles. Gold nanoparticles were in-situ synthesized after heating the silk fabrics immersed in gold ion solution. Localized surface plasmon resonance (LSPR) properties of the treated silk fabrics varied as the concentration of gold ions changed, in relation to the morphologies of gold nanoparticles on silk. In addition, X-ray diffraction (XRD) was used to observe the structure of the gold nanoparticle treated silk fabrics. The SERS enhancement effect of the silk fabrics treated with gold nanoparticles was evaluated by collecting Raman signals of different concentrations of p-aminothiophenol (PATP), 4-mercaptopyridine (4-MPy) and crystal violet (CV) solutions. The results demonstrate that the silk fabrics corresponding to 0.3 and 0.4 mM of gold ions possess high SERS activity compared to the other treated fabrics. It is suggested that both the gold content and morphologies of gold nanoparticles dominate the SERS effect of the treated silk fabrics.

  9. Towards Enhanced Performance Thin-film Composite Membranes via Surface Plasma Modification.

    Science.gov (United States)

    Reis, Rackel; Dumée, Ludovic F; Tardy, Blaise L; Dagastine, Raymond; Orbell, John D; Schutz, Jürg A; Duke, Mikel C

    2016-07-01

    Advancing the design of thin-film composite membrane surfaces is one of the most promising pathways to deal with treating varying water qualities and increase their long-term stability and permeability. Although plasma technologies have been explored for surface modification of bulk micro and ultrafiltration membrane materials, the modification of thin film composite membranes is yet to be systematically investigated. Here, the performance of commercial thin-film composite desalination membranes has been significantly enhanced by rapid and facile, low pressure, argon plasma activation. Pressure driven water desalination tests showed that at low power density, flux was improved by 22% without compromising salt rejection. Various plasma durations and excitation powers have been systematically evaluated to assess the impact of plasma glow reactions on the physico-chemical properties of these materials associated with permeability. With increasing power density, plasma treatment enhanced the hydrophilicity of the surfaces, where water contact angles decreasing by 70% were strongly correlated with increased negative charge and smooth uniform surface morphology. These results highlight a versatile chemical modification technique for post-treatment of commercial membrane products that provides uniform morphology and chemically altered surface properties.

  10. Rapid thyroid dysfunction screening based on serum surface-enhanced Raman scattering and multivariate statistical analysis

    Science.gov (United States)

    Tian, Dayong; Lü, Guodong; Zhai, Zhengang; Du, Guoli; Mo, Jiaqing; Lü, Xiaoyi

    2018-01-01

    In this paper, serum surface-enhanced Raman scattering and multivariate statistical analysis are used to investigate a rapid screening technique for thyroid function diseases. At present, the detection of thyroid function has become increasingly important, and it is urgently necessary to develop a rapid and portable method for the detection of thyroid function. Our experimental results show that, by using the Silmeco-based enhanced Raman signal, the signal strength greatly increases and the characteristic peak appears obviously. It is also observed that the Raman spectra of normal and anomalous thyroid function human serum are significantly different. Principal component analysis (PCA) combined with linear discriminant analysis (LDA) was used to diagnose thyroid dysfunction, and the diagnostic accuracy was 87.4%. The use of serum surface-enhanced Raman scattering technology combined with PCA–LDA shows good diagnostic performance for the rapid detection of thyroid function. By means of Raman technology, it is expected that a portable device for the rapid detection of thyroid function will be developed.

  11. Evaluation of FLIR/IR camera technology for airport surface surveillance

    Science.gov (United States)

    Castaldo, Rick; Franck, Charmaine C.; Smith, Alexander B.

    1996-05-01

    The Federal Aviation Administration (FAA) is evaluating Forward Looking Infrared (FLIR) and IR focal plane array technology as part of the Airport Surface Traffic Automation program. Under this program a new application for these technologies in aviation will be developed. The goal of the program is to evaluate FLIR and IR cameras for enhanced Air Traffic Control surface surveillance in all weather conditions for some major airports. Initially, FLIR cameras will be installed at airports with varying traffic densities to analyze and compare their capabilities along with other IR camera systems, displays and security/surveillance software. These cameras will be evaluated for both technical and operational performance. This paper discusses the initial studies that demonstrated the usefulness of FLIR technology for search and rescue situations and multiple coverage for integration with automatic surveillance systems. The general operation of the three IR camera systems to be evaluated in this study is presented. Finally, a concept for the possible integration of FLIR and IR technology with current automatic surface surveillance systems under development such as the Airport Movement Area Safety System and the Airport Traffic Identification System programs is proposed. This paper will conclude with a review of the FAA's future plans for evaluating a microbolometer based, uncooled IR camera system.

  12. An overview of technologies for immobilization of enzymes and surface analysis techniques for immobilized enzymes

    Science.gov (United States)

    Mohamad, Nur Royhaila; Marzuki, Nur Haziqah Che; Buang, Nor Aziah; Huyop, Fahrul; Wahab, Roswanira Abdul

    2015-01-01

    The current demands of sustainable green methodologies have increased the use of enzymatic technology in industrial processes. Employment of enzyme as biocatalysts offers the benefits of mild reaction conditions, biodegradability and catalytic efficiency. The harsh conditions of industrial processes, however, increase propensity of enzyme destabilization, shortening their industrial lifespan. Consequently, the technology of enzyme immobilization provides an effective means to circumvent these concerns by enhancing enzyme catalytic properties and also simplify downstream processing and improve operational stability. There are several techniques used to immobilize the enzymes onto supports which range from reversible physical adsorption and ionic linkages, to the irreversible stable covalent bonds. Such techniques produce immobilized enzymes of varying stability due to changes in the surface microenvironment and degree of multipoint attachment. Hence, it is mandatory to obtain information about the structure of the enzyme protein following interaction with the support surface as well as interactions of the enzymes with other proteins. Characterization technologies at the nanoscale level to study enzymes immobilized on surfaces are crucial to obtain valuable qualitative and quantitative information, including morphological visualization of the immobilized enzymes. These technologies are pertinent to assess efficacy of an immobilization technique and development of future enzyme immobilization strategies. PMID:26019635

  13. Electromagnetic theories of surface-enhanced Raman spectroscopy.

    Science.gov (United States)

    Ding, Song-Yuan; You, En-Ming; Tian, Zhong-Qun; Moskovits, Martin

    2017-07-07

    Surface-enhanced Raman spectroscopy (SERS) and related spectroscopies are powered primarily by the concentration of the electromagnetic (EM) fields associated with light in or near appropriately nanostructured electrically-conducting materials, most prominently, but not exclusively high-conductivity metals such as silver and gold. This field concentration takes place on account of the excitation of surface-plasmon (SP) resonances in the nanostructured conductor. Optimizing nanostructures for SERS, therefore, implies optimizing the ability of plasmonic nanostructures to concentrate EM optical fields at locations where molecules of interest reside, and to enhance the radiation efficiency of the oscillating dipoles associated with these molecules and nanostructures. This review summarizes the development of theories over the past four decades pertinent to SERS, especially those contributing to our current understanding of SP-related SERS. Special emphasis is given to the salient strategies and theoretical approaches for optimizing nanostructures with hotspots as efficient EM near-field concentrating and far-field radiating substrates for SERS. A simple model is described in terms of which the upper limit of the SERS enhancement can be estimated. Several experimental strategies that may allow one to approach, or possibly exceed this limit, such as cascading the enhancement of the local and radiated EM field by the multiscale EM coupling of hierarchical structures, and generating hotspots by hybridizing an antenna mode with a plasmonic waveguide cavity mode, which would result in an increased local field enhancement, are discussed. Aiming to significantly broaden the application of SERS to other fields, and especially to material science, we consider hybrid structures of plasmonic nanostructures and other material phases and strategies for producing strong local EM fields at desired locations in such hybrid structures. In this vein, we consider some of the numerical

  14. In situ surface-enhanced Raman spectroelectrochemical analysis system with a hemin modified nanostructured gold surface.

    Science.gov (United States)

    Yuan, Tao; Le Thi Ngoc, Loan; van Nieuwkasteele, Jan; Odijk, Mathieu; van den Berg, Albert; Permentier, Hjalmar; Bischoff, Rainer; Carlen, Edwin T

    2015-03-03

    An integrated surface-enhanced Raman scattering (SERS) spectroelectrochemical (SEC) analysis system is presented that combines a small volume microfluidic sample chamber (Raman spectroelectrochemistry. The SEC system includes a nanostructured Au surface that serves dual roles as the electrochemical working electrode (WE) and SERS substrate, a microfabricated Pt counter electrode (CE), and an external Ag/AgCl reference electrode (RE). The nanostructured Au WE enables highly sensitive in situ SERS spectroscopy through large and reproducible SERS enhancements, which eliminates the need for resonant wavelength matching of the laser excitation source with the electronic absorption of the target molecule. The new SEC analysis system has the merits of wide applicability to target molecules, small sample volume, and a low detection limit. We demonstrate in situ SERS spectroelectrochemistry measurements of the metalloporphyrin hemin showing shifts of the iron oxidation marker band ν4 with the nanostructured Au working electrode under precise potential control.

  15. Oxygen-depleted surfaces: a new antifouling technology.

    Science.gov (United States)

    Lindgren, J Fredrik; Haeffner, Mikael; Ericsson, Claes T; Jonsson, Per R

    2009-01-01

    A novel, non-toxic strategy to combat marine biofouling is presented. The technology is paint with additions of up to 43% of industrial protein. Through microbial degradation of the protein component, an oxygen-depleted layer rapidly forms in a 0.2 mm layer close to the paint surface. With the present paint formulations, a stable, O(2)-depleted layer can persist for 16 weeks. Barnacle larvae (cyprids) did not settle on panels where oxygen saturation was paint with protein reduced fouling by barnacles and bryozoans by 80% and close to 100%, respectively. The results suggest that this novel technology may be developed into a non-toxic alternative to copper-based antifouling paints, especially for pleasure boats in sensitive environments. There is clearly potential for further development of the paint formulation, and a full-scale test on a boat-hull suggested that service-life under realistic operations needs to be improved.

  16. Magnetic nanoparticles with surface modification enhanced gene delivery of HVJ-E vector.

    Science.gov (United States)

    Morishita, Norio; Nakagami, Hironori; Morishita, Ryuichi; Takeda, Shin-ichi; Mishima, Fumihito; Terazono, Bungo; Nishijima, Shigehiro; Kaneda, Yasufumi; Tanaka, Noriaki

    2005-09-09

    To enter the realm of human gene therapy, a novel drug delivery system is required for efficient delivery of small molecules with high safety for clinical usage. We have developed a unique vector "HVJ-E (hemagglutinating virus of Japan-envelope)" that can rapidly transfer plasmid DNA, oligonucleotide, and protein into cells by cell-fusion. In this study, we associated HVJ-E with magnetic nanoparticles, which can potentially enhance its transfection efficiency in the presence of a magnetic force. Magnetic nanoparticles, such as maghemite, with an average size of 29 nm, can be regulated by a magnetic force and basically consist of oxidized Fe which is commonly used as a supplement for the treatment of anemia. A mixture of magnetite particles with protamine sulfate, which gives a cationic surface charge on the maghemite particles, significantly enhanced the transfection efficiency in an in vitro cell culture system based on HVJ-E technology, resulting in a reduction in the required titer of HVJ. Addition of magnetic nanoparticles would enhance the association of HVJ-E with the cell membrane with a magnetic force. However, maghemite particles surface-coated with heparin, but not protamine sulfate, enhanced the transfection efficiency in the analysis of direct injection into the mouse liver in an in vivo model. The size and surface chemistry of magnetic particles could be tailored accordingly to meet specific demands of physical and biological characteristics. Overall, magnetic nanoparticles with different surface modifications can enhance HVJ-E-based gene transfer by modification of the size or charge, which could potentially help to overcome fundamental limitations to gene therapy in vivo.

  17. Liquid Metal Pump Technologies for Nuclear Surface Power

    Science.gov (United States)

    Polzin, Kurt A.

    2007-01-01

    Multiple liquid metal pump options are reviewed for the purpose of determining the technologies that are best suited for inclusion in a nuclear reactor thermal simulator intended to rest prototypical space nuclear surface power system components. Conduction, induction and thermoelectric electromagnetic pumps are evaluated based on their performance characteristics and the technical issues associated with incorporation into a reactor system. A thermoelectric electromagnetic pump is selected as the best option for use in NASA-MSFC's Fission Surface Power-Primary Test Circuit reactor simulator based on its relative simplicity, low power supply mass penalty, flight heritage, and the promise of increased pump efficiency over those earlier pump designs through the use of skutterudite thermoelectric elements.

  18. Status of reusable surface insulation thermal protection system technology programs

    Science.gov (United States)

    Greenshields, D. H.; Meyer, A. J.; Tillian, D. J.

    1972-01-01

    The development of three low-density rigidized insulation materials for the shuttle TPS application is reported. These materials consist of one high purity silica system and two systems based on mullite, an aluminum silicate. Both systems consist of fibers joined together with appropriate binders to obtain a rigidized insulation composite. Both material systems require the application of a glassy coating to provide a wear resistant, high emittance surface and to prevent the absorption of water by the fiber matrix. The technology program has addressed the development of water impervious coatings, methods of assembling the materials in design concepts while minimizing the thermal stress in the insulation, achieving compatibility between the RSI material and the structural system, and test evaluations to demonstrate the feasibility of the surface insulation concept.

  19. Gas detection by means of surface plasmon resonance enhanced ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Nooke, Alida

    2012-11-01

    This thesis investigated gas sensing by means of surface plasmon resonance enhanced ellipsometry. Surface plasmons were excited in a 40 - 50 nm gold layer by a He-Ne-laser using the Kretschmann configuration, which was arranged on a self-made copper measuring cell. A fixed angle of incidence and the ellipsometric parameter {Delta} as the measured value were used to monitor changes in the gas phase. Different types of gases were investigated: flammable (hydrocarbons and hydrogen), oxidising (oxygen and ozone), toxic (carbon monoxide) and inert (helium and nitrogen). The gas types can be distinguished by their refractive indices, whereas the sensor responds instantly relative to the reference gas with an increase or a decrease in {Delta}. Diluting the analyte gas with a reference gas (nitrogen or air) allowed the detection limits to be determined, these lay in the low % range. The sensor stability was also enhanced as well as the sensitivity by modifying the gold layers with a 3-10 nm additional layer. These additional layers consisted of the inorganic materials TiO{sub 2}, ZrO{sub 2}, MgF{sub 2} and Fe: SnO{sub 2} which were deposited by different coating processes. Surface investigations were made of every utilised layer: scanning electron microscope and atomic force microscope measurements for surface topology and spectroscopic ellipsometry mapping to determine the optical constants and the layer thicknesses. All applied materials protected the gold layer from contaminations and thus prolonged the life span of the sensor. Furthermore, the detection limits were reduced significantly, to the low ppm range. The material Fe: SnO{sub 2} demonstrates a special behaviour in reaction with the toxic gas carbon monoxide: Due to the iron doping, the response to carbon monoxide is extraordinary and concentrations below 1 ppm were detected. In order to approach a future application in industry, the sensor system was adapted to a stainless steel tube. With this measuring

  20. Nanostructure-enhanced surface plasmon resonance imaging (Conference Presentation)

    Science.gov (United States)

    Špašková, Barbora; Lynn, Nicholas S.; Slabý, Jiří Bocková, Markéta; Homola, Jiří

    2017-06-01

    There remains a need for the multiplexed detection of biomolecules at extremely low concentrations in fields of medical diagnostics, food safety, and security. Surface plasmon resonance imaging is an established biosensing approach in which the measurement of the intensity of light across a sensor chip is correlated with the amount of target biomolecules captured by the respective areas on the chip. In this work, we present a new approach for this method allowing for enhanced bioanalytical performance via the introduction of nanostructured sensing chip and polarization contrast measurement, which enable the exploitation of both amplitude and phase properties of plasmonic resonances on the nanostructures. Here we will discuss a complex theoretical analysis of the sensor performance, whereby we investigate aspects related to both the optical performance as well as the transport of the analyte molecules to the functionalized surfaces. This analysis accounts for the geometrical parameters of the nanostructured sensing surface, the properties of functional coatings, and parameters related to the detection assay. Based on the results of the theoretical analysis, we fabricated sensing chips comprised of arrays of gold nanoparticles (by electron-beam lithography), which were modified by a biofunctional coating to allow for the selective capturing of the target biomolecules in the regions with high sensitivity. In addition, we developed a compact optical reader with an integrated microfluidic cell, allowing for the measurement from 50 independent sensing channels. The performance of this biosensor is demonstrated through the sensitive detection of short oligonucleotides down to the low picomolar level.

  1. An AES Study of the Room Temperature Surface Conditioning of Technological Metal Surfaces by Electron Irradiation

    CERN Document Server

    Scheuerlein, C; Taborelli, M; Brown, A; Baker, M A

    2002-01-01

    The modifications to technological copper and niobium surfaces induced by 2.5 keV electron irradiation have been investigated in the context of the conditioning process occurring in particle accelerator ultra high vacuum systems. Changes in the elemental surface composition have been found using Scanning Auger Microscopy (SAM) by monitoring the carbon, oxygen and metal Auger peak intensities as a function of electron irradiation in the dose range 10-6 to 10-2 C mm-2. The surface analysis results are compared with electron dose dependent secondary electron and electron stimulated desorption yield measurements. Initially the electron irradiation causes a surface cleaning through electron stimulated desorption, in particular of hydrogen. During this period both the electron stimulated desorption and secondary electron yield decrease as a function of electron dose. When the electron dose exceeds 10-4 C mm-2 electron stimulated desorption yields are reduced by several orders of magnitude and the electron beam indu...

  2. Aircrew Performance Cutting-Edge Technology: Emerging Human Performance Enhancement Technology Vision in Support of Operational Military Aviation Strategy

    National Research Council Canada - National Science Library

    Belland, Kris M

    2003-01-01

    Using cutting-edge technology to create a human factors advantage in military operations will contribute to success on the battlefield of the future whether below the surface, on the surface, in the air, or in space...

  3. Digital innovations and emerging technologies for enhanced recovery programmes

    DEFF Research Database (Denmark)

    Michard, F; Gan, T J; Kehlet, H

    2017-01-01

    .Preoperative physical condition, a major determinant of postoperative outcome, could be optimized with the use of text messages (SMS) or digital applications (Apps) designed to facilitate smoking cessation, modify physical activity, and better manage hypertension and diabetes. Several non-invasive haemodynamic......Enhanced recovery programmes (ERPs) are increasingly used to improve post-surgical recovery. However, compliance to various components of ERPs-a key determinant of success-remains sub-optimal. Emerging technologies have the potential to help patients and caregivers to improve compliance with ERPs......-respiratory function may help in the early detection of clinical deterioration during the postoperative recovery and to address 'failure to rescue'. Activity trackers may be useful to monitor early mobilization, another major element of ERPs. Finally, electronic checklists have been developed to ensure that none...

  4. Knowledge Generation in Technology-Enhanced Health Exhibitions

    DEFF Research Database (Denmark)

    Magnussen, Rikke; Kharlamov, Nikita; Zachariasssen, Maria

    2016-01-01

    This paper presents results from eye-tracking studies of audience interaction and knowledge generation in the technology-enhanced health promotion exhibition PULSE at a science centre in Copenhagen, Denmark. The main purpose of the study was to understand what types of knowledge audiences build...... in health promotion exhibitions designed to include direct physical interaction. The current study is part of the larger PULSE project, which aims to develop innovative health promotion activities that include a science museum exhibition as a key setting. The primary target group is families with children...... the science centre. Eye-tracking glasses and qualitative interviews were used to collect data. Before entering the PULSE exhibition, one adult in each family group and one child in each school group were asked to wear eye-tracking equipment while interacting with various installations. Primarily adult test...

  5. Human Enhancement Technologies. Verso nuovi modelli antropologici Parte I

    Directory of Open Access Journals (Sweden)

    Luca Lo Sapio

    2013-01-01

    Full Text Available This paper deals with the important topic of human enhancement and tries to focus the question under a new perspective. The international debate is focused around two main theoretical positions: bio-conservatorism and techno-enthusiasm. We seem to be forced to choose one or another conception in order to understand the relationship between human beings and technology. The first part of the paper analyzes different authors trying to circumscribe the principal features of each one. We can notice two main paradigms which are incapable to rightly understand the phenomenon we are considering. The relieves emerging in the first part will be suitable to prosecute the analysis in the second part of the work.

  6. Analysis of polymer surfaces and thin-film coatings with Raman and surface enhanced Raman scattering

    CERN Document Server

    McAnally, G D

    2001-01-01

    This thesis investigates the potential of surface-enhanced Raman scattering (SERS) for the analysis and characterisation of polymer surfaces. The Raman and SERS spectra from a PET film are presented. The SERS spectra from the related polyester PBT and from the monomer DMT are identical to PET, showing that only the aromatic signals are enhanced. Evidence from other compounds is presented to show that loss of the carbonyl stretch (1725 cm sup - sup 1) from the spectra is due to a chemical interaction between the silver and surface carbonyl groups. The interaction of other polymer functional groups with silver is discussed. A comparison of Raman and SERS spectra collected from three faces of a single crystal shows the SERS spectra are depolarised. AFM images of the silver films used to obtain SERS are presented. They consist of regular islands of silver, fused together to form a complete film. The stability and reproducibility and of these surfaces is assessed. Band assignments for the SERS spectrum of PET are ...

  7. Recovery rates, enhanced oil recovery and technological limits.

    Science.gov (United States)

    Muggeridge, Ann; Cockin, Andrew; Webb, Kevin; Frampton, Harry; Collins, Ian; Moulds, Tim; Salino, Peter

    2014-01-13

    Enhanced oil recovery (EOR) techniques can significantly extend global oil reserves once oil prices are high enough to make these techniques economic. Given a broad consensus that we have entered a period of supply constraints, operators can at last plan on the assumption that the oil price is likely to remain relatively high. This, coupled with the realization that new giant fields are becoming increasingly difficult to find, is creating the conditions for extensive deployment of EOR. This paper provides a comprehensive overview of the nature, status and prospects for EOR technologies. It explains why the average oil recovery factor worldwide is only between 20% and 40%, describes the factors that contribute to these low recoveries and indicates which of those factors EOR techniques can affect. The paper then summarizes the breadth of EOR processes, the history of their application and their current status. It introduces two new EOR technologies that are beginning to be deployed and which look set to enter mainstream application. Examples of existing EOR projects in the mature oil province of the North Sea are discussed. It concludes by summarizing the future opportunities for the development and deployment of EOR.

  8. S. Johannes in Jerusalem Church: enhancement through technological analysis

    Directory of Open Access Journals (Sweden)

    Andrea Sichi

    2014-10-01

    Full Text Available The research aims to exhaust the store of knowledge on a nearly one thousand years monument through the study and the interpretation of ancient technological devices that have generated unique formal characteristics. The analysis on the church of the Castello della Magione in Poggibonsi, monumental complex near the ancient Via Francigena, face the evolutionary history in an attempt to fill the lack of documentation. Critical observation of the monument, direct survey of technological and structural devices, punctual measurements aimed at verifying the hypothesis, reconstruction carried out in the field and reworking of data in post-production are the distinctive characteristics of the search method. In particular, we have achieved the following results: hypothesis of self-supporting during construction of a brick vault not coeval with the church; formal interpretation of the unique denticular single-lancet window of the church’s main front, that has so far left scholars' curiosity unsatisfied; detection of the method for tracking the monument and the proportional relationships used to its location in relation to the existing context; he explanation of the peculiar and irregular orientation of the church; assumptions about the dating of the monument, still uncertain because of the lack of documents; in general, the complete knowledge of the monument aimed to provide useful tools for the enhancement and for a correct approach in case of any restoration.

  9. Heating Unsaturated Sediments Using Solar Energy to Enhance Passive Sediment Remediation Technologies

    Science.gov (United States)

    Rossman, A.

    2002-12-01

    Sediment heating has been shown to enhance passive sediment remediation technologies such as bioremediation and barometric pumping (passive soil venting). Sediment heating raises the slow remediation rates that often limit the widespread use of these technologies. In bioremediation applications, a 10 degree C increase in subsurface temperature is expected to double the microbial activity, and thus the remediation rate. The removal rate of tetracholorethylene (PCE - a common subsurface contaminant) by passive soil vapor extraction is expected to nearly double in low-permeable sediments when the subsurface is heated 10 degree C from ambient temperatures due to an increased vapor pressure in the PCE. When the sediment is heated using renewable energy sources, these thermally enhanced remediation technologies can be environmentally benign alternatives to conventional remediation techniques that rely on large external energy inputs. The thermally enhanced passive technologies may be particularly useful for remediating unsaturated, low-permeable lenses that are troublesome to most conventional remediation technologies such as conventional soil vapor extraction and co-solvent flushes. The main objective of this work was to quantify subsurface sediment heating using a solar powered heat injection well. To do this, a pilot sediment heating system was installed in Vermont and high resolution meteorological and sediment temperature data were collected using a stand-alone data acquisition system. Unsaturated, silty sediments were heated in-situ by converting the direct and indirect solar energy available at the surface to heat energy in the subsurface using stand-alone renewable energy sources and a resistive element heat injection well. The heat injection well was powered by a 600-W passively tracking photovoltaic (PV) array and a small 1.2-m swept area wind turbine. It is envisioned that the heat injection well would be placed directly into an area of high subsurface

  10. Efficiency Enhancement of Silicon Solar Cells by Porous Silicon Technology

    Directory of Open Access Journals (Sweden)

    Eugenijus SHATKOVSKIS

    2012-09-01

    Full Text Available Silicon solar cells produced by a usual technology in p-type, crystalline silicon wafer were investigated. The manufactured solar cells were of total thickness 450 mm, the junction depth was of 0.5 mm – 0.7 mm. Porous silicon technologies were adapted to enhance cell efficiency. The production of porous silicon layer was carried out in HF: ethanol = 1 : 2 volume ratio electrolytes, illuminating by 50 W halogen lamps at the time of processing. The etching current was computer-controlled in the limits of (6 ÷ 14 mA/cm2, etching time was set in the interval of (10 ÷ 20 s. The characteristics and performance of the solar cells samples was carried out illuminating by Xenon 5000 K lamp light. Current-voltage characteristic studies have shown that porous silicon structures produced affect the extent of dark and lighting parameters of the samples. Exactly it affects current-voltage characteristic and serial resistance of the cells. It has shown, the formation of porous silicon structure causes an increase in the electric power created of solar cell. Conversion efficiency increases also respectively to the initial efficiency of cell. Increase of solar cell maximum power in 15 or even more percent is found. The highest increase in power have been observed in the spectral range of Dl @ (450 ÷ 850 nm, where ~ 60 % of the A1.5 spectra solar energy is located. It has been demonstrated that porous silicon technology is effective tool to improve the silicon solar cells performance.DOI: http://dx.doi.org/10.5755/j01.ms.18.3.2428

  11. Plasmonic nanopillar structures for surface-enhanced raman scattering applications

    DEFF Research Database (Denmark)

    Rindzevicius, Tomas; Schmidt, Michael Stenbæk; Wu, Kaiyu

    2016-01-01

    experimentally and theoretically. Simulations show that that a single Agcoated NP supports two LSPR modes, i.e. the particle mode and the Ag cap resonant cavity mode. The Ag cap resonant cavity mode contributes most to the enhancement of the Raman scattering signal. The electric field distribution calculations...... have been utilized in surfaceenhanced Raman spectroscopy (SERS) for biological and chemical sensing. We present Au nanopillar (NP) SERS structures that are excellent for molecular detection. The NP structures can be fabricated using a simple two-step process. We analyze NP optical properties...... show that the EM hot spots are located at the bottom of the Ag cap which is important observation for practical SERS sensing. Reproducible and repeatable SERS signal intensities can be obtained across large surface areas (>mm2). Application examples include detection of TAMRA-labeled vasopressin...

  12. Single Molecule Detection Using Surface-Enhanced Raman Scattering (SERS)

    Energy Technology Data Exchange (ETDEWEB)

    Kneipp, K.; Wang, Y.; Kneipp, H.; Perelman, L.T.; Itzkan, I.; Dasari, R.R.; Feld, M.S. [George R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)]|[Department of Physics, Technical University of Berlin, D 10623 Berlin (Germany)

    1997-03-01

    By exploiting the extremely large effective cross sections (10{sup -17}{endash}10{sup -16}cm{sup 2}/molecule) available from surface-enhanced Raman scattering (SERS), we achieved the first observation of single molecule Raman scattering. Measured spectra of a single crystal violet molecule in aqueous colloidal silver solution using one second collection time and about 2{times}10{sup 5}W/cm{sup 2} nonresonant near-infrared excitation show a clear {open_quotes}fingerprint{close_quotes} of its Raman features between 700 and 1700cm{sup -1}. Spectra observed in a time sequence for an average of 0.6 dye molecule in the probed volume exhibited the expected Poisson distribution for actually measuring 0, 1, 2, or 3 molecules. {copyright} {ital 1997} {ital The American Physical Society}

  13. Reproducible surface-enhanced Raman spectroscopy of small molecular anions

    Science.gov (United States)

    Owens, F. J.

    2011-03-01

    A gold-coated silicon substrate having an array of pyramidal shaped holes is shown to provide a reproducible surface-enhanced Raman spectra (SERS) in a number of inorganic ions such as ? , ? , ? , and ? deposited on the substrate as 10-3 to10-4 molar aqueous solutions of their salts. Of particular interest is the observation of a SERS effect in ? , the anion of ammonium nitrate, a commonly used terrorist explosive, suggesting the potential for sensitive detection of this material. An unusual increase in the frequency of the ? bending mode frequency is observed in the SERS spectra of KNO2. Density Functional Theory calculations of the frequencies of the normal modes of vibration of ? bonded to gold predict an upward shift of the frequencies compared with the calculated results for a free ? , suggesting a possible explanation for the shifts.

  14. Light-emitting diodes enhanced by localized surface plasmon resonance.

    Science.gov (United States)

    Gu, Xuefeng; Qiu, Teng; Zhang, Wenjun; Chu, Paul K

    2011-03-08

    Light-emitting diodes [LEDs] are of particular interest recently as their performance is approaching fluorescent/incandescent tubes. Moreover, their energy-saving property is attracting many researchers because of the huge energy crisis we are facing. Among all methods intending to enhance the efficiency and intensity of a conventional LED, localized surface plasmon resonance is a promising way. The mechanism is based on the energy coupling effect between the emitted photons from the semiconductor and metallic nanoparticles fabricated by nanotechnology. In this review, we describe the mechanism of this coupling effect and summarize the common fabrication techniques. The prospect, including the potential to replace fluorescent/incandescent lighting devices as well as applications to flat panel displays and optoelectronics, and future challenges with regard to the design of metallic nanostructures and fabrication techniques are discussed.

  15. Light-emitting diodes enhanced by localized surface plasmon resonance

    Directory of Open Access Journals (Sweden)

    Zhang Wenjun

    2011-01-01

    Full Text Available Abstract Light-emitting diodes [LEDs] are of particular interest recently as their performance is approaching fluorescent/incandescent tubes. Moreover, their energy-saving property is attracting many researchers because of the huge energy crisis we are facing. Among all methods intending to enhance the efficiency and intensity of a conventional LED, localized surface plasmon resonance is a promising way. The mechanism is based on the energy coupling effect between the emitted photons from the semiconductor and metallic nanoparticles fabricated by nanotechnology. In this review, we describe the mechanism of this coupling effect and summarize the common fabrication techniques. The prospect, including the potential to replace fluorescent/incandescent lighting devices as well as applications to flat panel displays and optoelectronics, and future challenges with regard to the design of metallic nanostructures and fabrication techniques are discussed.

  16. Light-emitting diodes enhanced by localized surface plasmon resonance

    Science.gov (United States)

    Gu, Xuefeng; Qiu, Teng; Zhang, Wenjun; Chu, Paul K.

    2011-12-01

    Light-emitting diodes [LEDs] are of particular interest recently as their performance is approaching fluorescent/incandescent tubes. Moreover, their energy-saving property is attracting many researchers because of the huge energy crisis we are facing. Among all methods intending to enhance the efficiency and intensity of a conventional LED, localized surface plasmon resonance is a promising way. The mechanism is based on the energy coupling effect between the emitted photons from the semiconductor and metallic nanoparticles fabricated by nanotechnology. In this review, we describe the mechanism of this coupling effect and summarize the common fabrication techniques. The prospect, including the potential to replace fluorescent/incandescent lighting devices as well as applications to flat panel displays and optoelectronics, and future challenges with regard to the design of metallic nanostructures and fabrication techniques are discussed.

  17. Detection of explosives based on surface-enhanced Raman spectroscopy.

    Science.gov (United States)

    Wackerbarth, Hainer; Salb, Christian; Gundrum, Lars; Niederkrüger, Matthias; Christou, Konstantin; Beushausen, Volker; Viöl, Wolfgang

    2010-08-10

    In this study we present a device based on surface-enhanced Raman scattering (SERS) for the detection of airborne explosives. The explosives are resublimated on a cooled nanostructured gold substrate. The explosives trinitrotoluene (TNT) and triacetone triperoxide (TATP) are used. The SERS spectrum of the explosives is analyzed. Thus, TNT is deposited from an acetonitrile solution on the gold substrate. In the case of TATP, first the bulk TATP Raman spectrum was recorded and compared with the SERS spectrum, generated by deposition out of the gas phase. The frequencies of the SERS spectrum are hardly shifted compared to the spectrum of bulk TATP. The influence of the nanostructured gold substrate temperature on the signals of TATP was studied. A decrease in temperature up to 200 K increased the intensities of the TATP bands in the SERS spectrum; below 200 K, the TATP fingerprint disappeared.

  18. New Material Development for Surface Layer and Surface Technology in Tribology Science to Improve Energy Efficiency

    Science.gov (United States)

    Ismail, R.; Tauviqirrahman, M.; Jamari, Jamari; Schipper, D. J.

    2009-09-01

    This paper reviews the development of new material and surface technology in tribology and its contribution to energy efficiency. Two examples of the economic benefits, resulted from the optimum tribology in the transportation sector and the manufacturing industry are discussed. The new materials are proposed to modify the surface property by laminating the bulk material with thin layer/coating. Under a suitable condition, the thin layer on a surface can provide a combination of good wear, a low friction and corrosion resistance for the mechanical components. The innovation in layer technology results molybdenum disulfide (MoS2), diamond like carbon (DLC), cubic boron nitride (CBN) and diamond which perform satisfactory outcome. The application of the metallic coatings to carbon fibre reinforced polymer matrix composites (CFRP) has the capacity to provide considerable weight and power savings for many engineering components. The green material for lubricant and additives such as the use of sunflower oil which possesses good oxidation resistance and the use of mallee leaves as bio-degradable solvent are used to answer the demand of the environmentally friendly material with good performance. The tribology research implementation for energy efficiency also touches the simple things around us such as: erasing the laser-print in a paper with different abrasion techniques. For the technology in the engineering surface, the consideration for generating the suitable surface of the components in running-in period has been discussed in order to prolong the components life and reduce the machine downtime. The conclusion, tribology can result in reducing manufacturing time, reducing the maintenance requirements, prolonging the service interval, improving durability, reliability and mechanical components life, and reducing harmful exhaust emission and waste. All of these advantages will increase the energy efficiency and the economic benefits.

  19. New Material Development for Surface Layer and Surface Technology in Tribology Science to Improve Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, R., E-mail: rifky-mec@yahoo.com; Tauviqirrahman, M., E-mail: rifky-mec@yahoo.com [Laboratory for Engineering Design and Tribology, Department of Mechanical Engineering, University of Diponegoro, Semarang, Indonesia and Jl. Prof. Sudharto, Kampus UNDIP Tembalang, Semarang (Indonesia); Laboratory for Surface Technology and Tribology, Faculty of Engineering Technology, University of Twente, Enschede (Netherlands); Jamari, E-mail: rifky-mec@yahoo.com [Laboratory for Engineering Design and Tribology, Department of Mechanical Engineering, University of Diponegoro, Semarang, Indonesia and Jl. Prof. Sudharto, Kampus UNDIP Tembalang, Semarang (Indonesia); Schipper, D. J., E-mail: rifky-mec@yahoo.com [Laboratory for Surface Technology and Tribology, Faculty of Engineering Technology, University of Twente, Enschede (Netherlands)

    2009-09-14

    This paper reviews the development of new material and surface technology in tribology and its contribution to energy efficiency. Two examples of the economic benefits, resulted from the optimum tribology in the transportation sector and the manufacturing industry are discussed. The new materials are proposed to modify the surface property by laminating the bulk material with thin layer/coating. Under a suitable condition, the thin layer on a surface can provide a combination of good wear, a low friction and corrosion resistance for the mechanical components. The innovation in layer technology results molybdenum disulfide (MoS2), diamond like carbon (DLC), cubic boron nitride (CBN) and diamond which perform satisfactory outcome. The application of the metallic coatings to carbon fibre reinforced polymer matrix composites (CFRP) has the capacity to provide considerable weight and power savings for many engineering components. The green material for lubricant and additives such as the use of sunflower oil which possesses good oxidation resistance and the use of mallee leaves as bio‐degradable solvent are used to answer the demand of the environmentally friendly material with good performance. The tribology research implementation for energy efficiency also touches the simple things around us such as: erasing the laser‐print in a paper with different abrasion techniques. For the technology in the engineering surface, the consideration for generating the suitable surface of the components in running‐in period has been discussed in order to prolong the components life and reduce the machine downtime. The conclusion, tribology can result in reducing manufacturing time, reducing the maintenance requirements, prolonging the service interval, improving durability, reliability and mechanical components life, and reducing harmful exhaust emission and waste. All of these advantages will increase the energy efficiency and the economic benefits.

  20. Cancer imaging using surface-enhanced resonance Raman scattering nanoparticles.

    Science.gov (United States)

    Harmsen, Stefan; Wall, Matthew A; Huang, Ruimin; Kircher, Moritz F

    2017-07-01

    The unique spectral signatures and biologically inert compositions of surface-enhanced resonance Raman scattering (SERRS) nanoparticles make them promising contrast agents for in vivo cancer imaging. Our SERRS nanoparticles consist of a 60-nm gold nanoparticle core that is encapsulated in a 15-nm-thick silica shell wherein the resonant Raman reporter is embedded. Subtle aspects of their preparation can shift their limit of detection by orders of magnitude. In this protocol, we present the optimized, step-by-step procedure for generating reproducible SERRS nanoparticles with femtomolar (10-15 M) limits of detection. We provide ways of characterizing the optical properties of SERRS nanoparticles using UV/VIS and Raman spectroscopy, and their physicochemical properties using transmission electron microscopy and nanoparticle tracking analysis. We introduce several applications of these nanoprobes for biomedical research, with a focus on intraoperative cancer imaging via Raman imaging. A detailed account is provided for successful i.v. administration of SERRS nanoparticles such that delineation of cancerous lesions can be achieved in vivo and ex vivo on resected tissues without the need for specific biomarker targeting. This straightforward, yet comprehensive, protocol-from initial de novo gold nanoparticle synthesis to SERRS nanoparticle contrast-enhanced preclinical Raman imaging in animal models-takes ∼96 h.

  1. Toward surface-enhanced Raman imaging of latent fingerprints.

    Science.gov (United States)

    Connatser, R Maggie; Prokes, Sharka M; Glembocki, Orest J; Schuler, Rebecca L; Gardner, Charles W; Lewis, Samuel A; Lewis, Linda A

    2010-11-01

    Exposure to light or heat, or simply a dearth of fingerprint material, renders some latent fingerprints undetectable using conventional methods. We begin to address such elusive fingerprints using detection targeting photo- and thermally stable fingerprint constituents: surface-enhanced Raman spectroscopy (SERS). SERS can give descriptive vibrational spectra of amino acids, among other robust fingerprint constituents, and good sensitivity can be attained by improving metal-dielectric nanoparticle substrates. With SERS chemical imaging, vibrational bands' intensities recreate a visual of fingerprint topography. The impact of nanoparticle synthesis route, dispersal methodology-deposition solvent, and laser wavelength are discussed, as are data from enhanced vibrational spectra of fingerprint components. SERS and Raman chemical images of fingerprints and realistic contaminants are shown. To our knowledge, this represents the first SERS imaging of fingerprints. In conclusion, this work progresses toward the ultimate goal of vibrationally detecting latent prints that would otherwise remain undetected using traditional development methods. 2010 American Academy of Forensic Sciences. Published 2010. This article is a U.S. Government work and is in the public domain in the U.S.A.

  2. Silicon nanohybrid-based surface-enhanced Raman scattering sensors.

    Science.gov (United States)

    Wang, Houyu; Jiang, Xiangxu; Lee, Shuit-Tong; He, Yao

    2014-11-01

    Nanomaterial-based surface-enhanced Raman scattering (SERS) sensors are highly promising analytical tools, capable of ultrasensitive, multiplex, and nondestructive detection of chemical and biological species. Extensive efforts have been made to design various silicon nanohybrid-based SERS substrates such as gold/silver nanoparticle (NP)-decorated silicon nanowires, Au/Ag NP-decorated silicon wafers (AuNP@Si), and so forth. In comparison to free AuNP- and AgNP-based SERS sensors, the silicon nanohybrid-based SERS sensors feature higher enhancement factors (EFs) and excellent reproducibility, since SERS hot spots are efficiently coupled and stabilized through interconnection to the semiconducting silicon substrates. Consequently, in the past decade, giant advancements in the development of silicon nanohybrid-based SERS sensors have been witnessed for myriad sensing applications. In this review, the representative achievements related to the design of high-performance silicon nanohybrid-based SERS sensors and their use for chemical and biological analysis are reviewed in a detailed way. Furthermore, the major opportunities and challenges in this field are discussed from a broad perspective and possible future directions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Land surface changes enhanced drought over the Loess Plateau

    Science.gov (United States)

    Xu, Xianli; Liu, Meixian

    2017-04-01

    In order to prevent the severe soil-water erosion over the Loess Plateau (LP), the Chinese Government initiated large scale ecological restoration (ER) in the past half century. The ER had successfully reduced soil erosion however also changed the land surface and altered the regional water-energy balance and consequently the dryness/wetness conditions, which in turn affects the vegetation. Knowledge of the impacts of the ER on dryness/wetness conditions is essential for developing future effective ER measures. For this purpose, a new drought index, the standardized wetness index (SWI), was proposed. The SWI can represent the dryness/wetness brought by solely climate change (denoted as SWIf in this case), and the dryness/wetness brought by the joint effects of climate change and land surface change (SWI_m). A total of 13 main catchments were selected to investigate the effects of ER on dryness/wetness conditions during 1961-2009 over LP. Results showed that the overall increasing parameter n (a parameter of the Budyko formulae) could be well explained by the ER measures (R^2=1) in these catchments. The SWIf and SWIm had similar fluctuating features and exhibited downward trends. However, the SWIm had larger negative trends than the SWI_f, implying that ER actions enhanced the drought conditions over the drying LP in the past decades. Therefore, we suggest that the government should manage and maintain the existing achievements but not further expand revegetation because of unintended consequences on drought vulnerability.

  4. Experimental Design on Laminated Veneer Lumber Fiber Composite: Surface Enhancement

    Science.gov (United States)

    Meekum, U.; Mingmongkol, Y.

    2010-06-01

    Thick laminate veneer lumber(LVL) fibre reinforced composites were constructed from the alternated perpendicularly arrayed of peeled rubber woods. Glass woven was laid in between the layers. Native golden teak veneers were used as faces. In house formulae epoxy was employed as wood adhesive. The hand lay-up laminate was cured at 150° C for 45 mins. The cut specimen was post cured at 80° C for at least 5 hours. The 2k factorial design of experimental(DOE) was used to verify the parameters. Three parameters by mean of silane content in epoxy formulation(A), smoke treatment of rubber wood surface(B) and anti-termite application(C) on the wood surface were analysed. Both low and high levels were further subcategorised into 2 sub-levels. Flexural properties were the main respond obtained. ANOVA analysis of the Pareto chart was engaged. The main effect plot was also testified. The results showed that the interaction between silane quantity and termite treatment is negative effect at high level(AC+). Vice versa, the interaction between silane and smoke treatment was positive significant effect at high level(AB+). According to this research work, the optimal setting to improve the surface adhesion and hence flexural properties enhancement were high level of silane quantity, 15% by weight, high level of smoked wood layers, 8 out of 14 layers, and low anti termite applied wood. The further testes also revealed that the LVL composite had superior properties that the solid woods but slightly inferior in flexibility. The screw withdrawn strength of LVL showed the higher figure than solid wood. It is also better resistance to moisture and termite attack than the rubber wood.

  5. Enhanced bioactivity and osseointegration of PEEK with accelerated neutral atom beam technology.

    Science.gov (United States)

    Khoury, Joseph; Maxwell, Melissa; Cherian, Raymond E; Bachand, James; Kurz, Arthur C; Walsh, Michael; Assad, Michel; Svrluga, Richard C

    2017-04-01

    Polyetheretherketone (PEEK) is growing in popularity for orthopedic, spinal, and trauma applications but has potential significant limitations in use. PEEK is biocompatible, similar in elasticity to bone, and radiolucent, but is inert and therefore does not integrate well with bone. Current efforts are focusing on increasing the bioactivity of PEEK with surface modifications to improve the bone-implant interface. We used a novel Accelerated Neutral Atom Beam (ANAB) technology to enhance the bioactivity of PEEK. Human osteoblast-like cells seeded on ANAB-treated PEEK result in significantly enhanced proliferation compared with control PEEK. Cells grown on ANAB-treated PEEK increase osteogenic expression of ALPL (1.98-fold, p PEEK implants resulted in enhanced bone-in-contact by 3.09-fold (p PEEK has the potential to enhance its bioactivity, leading to bone formation and significantly decreasing osseointegration time of orthopedic and spinal implants. ANAB treatment, therefore, may significantly enhance the performance of PEEK medical implants and lead to improved clinical outcomes. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 531-543, 2017. © 2015 Wiley Periodicals, Inc.

  6. Sensitivity improved surface plasmon resonance biosensor for cancer biomarker detection based on plasmonic enhancement.

    Science.gov (United States)

    Law, Wing-Cheung; Yong, Ken-Tye; Baev, Alexander; Prasad, Paras N

    2011-06-28

    In this study, we report the development of a nanoparticle-enhanced biosensor by integrating both the nanoparticles and immunoassay sensing technologies into a phase interrogation surface plasmon resonance (SPR) system for detecting antigen at a concentration as low as the femtomolar range. Our work has demonstrated that the plasmonic field extension generated from the gold film to gold nanorod (GNR) has led to a drastic sensitivity enhancement. Antibody-functionalized sensing film, together with antibody-conjugated GNRs, was readily served as a plasmonic coupling partner that can be used as a powerful ultrasensitive sandwich immunoassay for cancer-related disease detection. Experimentally, it was found that the bioconjugated GNR labels enhance the tumor necrosis factor alpha (TNF-α) antigen signal with more than 40-fold increase compared to the traditional SPR biosensing technique. The underlying principle was analyzed by simulating the near-field coupling between the sensing film and the GNR. The results have shown that GNRs were readily served as promising amplification labels in SPR sensing technology.

  7. Fiber Surface Modification Technology for Fiber-Optic Localized Surface Plasmon Resonance Biosensors

    Directory of Open Access Journals (Sweden)

    Jijun Xiong

    2012-02-01

    Full Text Available Considerable studies have been performed on the development of optical fiber sensors modified by gold nanoparticles based on the localized surface plasmon resonance (LSPR technique. The current paper presents a new approach in fiber surface modification technology for biosensors. Star-shaped gold nanoparticles obtained through the seed-mediated solution growth method were found to self-assemble on the surface of tapered optical fibers via amino- and mercapto-silane coupling agents. Transmitted power spectra of 3-aminopropyltrimethoxy silane (APTMS-modified fiber were obtained, which can verify that the silane coupling agent surface modification method is successful. Transmission spectra are characterized in different concentrations of ethanol and gentian violet solutions to validate the sensitivity of the modified fiber. Assembly using star-shaped gold nanoparticles and amino/mercapto silane coupling agent are analyzed and compared. The transmission spectra of the gold nanoparticles show that the nanoparticles are sensitive to the dielectric properties of the surrounding medium. After the fibers are treated in t-dodecylmercaptan to obtain their transmission spectra, APTMS-modified fiber becomes less sensitive to different media, except that modified by 3-mercaptopropyltrimethoxy silane (MPTMS. Experimental results of the transmission spectra show that the surface modified by the gold nanoparticles using MPTMS is firmer compared to that obtained using APTMS.

  8. Pipeline coating inspection in Mexico applying surface electromagnetic technology

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, O.; Mousatov, A.; Nakamura, E.; Villarreal, J.M. [Instituto Mexicano del Petroleo (IMP), Mexico City (Mexico); Shevnin, V. [Moscow State University (Russian Federation); Cano, B. [Petroleos Mexicanos (PEMEX), Mexico City (Mexico)

    2009-07-01

    The main problems in the pipeline systems in Mexico include: extremely aggressive soil characterized by a high clay content and low resistivity, interconnection between several pipes, including electrical contacts of active pipelines with out of service pipes, and short distances between pipes in comparison with their depths which reduce the resolution of coating inspection. The results presented in this work show the efficiency of the Surface Electromagnetic Pipeline Inspection (SEMPI) technology to determine the technical condition of pipelines in situations before mentioned. The SEMPI technology includes two stages: regional and detailed measurements. The regional stage consists of magnetic field measurements along the pipeline using large distances (10 - 100 m) between observation points to delimit zones with damaged coating. For quantitative assessing the leakage and coating resistances along pipeline, additional measurements of voltage and soil resistivity measurements are performed. The second stage includes detailed measurements of the electric field on the pipe intervals with anomalous technical conditions identified in the regional stage. Based on the distribution of the coating electric resistance and the subsoil resistivity values, the delimitation of the zones with different grade of coating quality and soil aggressiveness are performed. (author)

  9. Label-Enhanced Surface Plasmon Resonance: A New Concept for Improved Performance in Optical Biosensor Analysis

    Directory of Open Access Journals (Sweden)

    Niko Granqvist

    2013-11-01

    Full Text Available Surface plasmon resonance (SPR is a well-established optical biosensor technology with many proven applications in the study of molecular interactions as well as in surface and material science. SPR is usually applied in the label-free mode which may be advantageous in cases where the presence of a label may potentially interfere with the studied interactions per se. However, the fundamental challenges of label-free SPR in terms of limited sensitivity and specificity are well known. Here we present a new concept called label-enhanced SPR, which is based on utilizing strongly absorbing dye molecules in combination with the evaluation of the full shape of the SPR curve, whereby the sensitivity as well as the specificity of SPR is significantly improved. The performance of the new label-enhanced SPR method was demonstrated by two simple model assays: a small molecule assay and a DNA hybridization assay. The small molecule assay was used to demonstrate the sensitivity enhancement of the method, and how competitive assays can be used for relative affinity determination. The DNA assay was used to demonstrate the selectivity of the assay, and the capabilities in eliminating noise from bulk liquid composition variations.

  10. Label-Enhanced Surface Plasmon Resonance: A New Concept for Improved Performance in Optical Biosensor Analysis

    Science.gov (United States)

    Granqvist, Niko; Hanning, Anders; Eng, Lars; Tuppurainen, Jussi; Viitala, Tapani

    2013-01-01

    Surface plasmon resonance (SPR) is a well-established optical biosensor technology with many proven applications in the study of molecular interactions as well as in surface and material science. SPR is usually applied in the label-free mode which may be advantageous in cases where the presence of a label may potentially interfere with the studied interactions per se. However, the fundamental challenges of label-free SPR in terms of limited sensitivity and specificity are well known. Here we present a new concept called label-enhanced SPR, which is based on utilizing strongly absorbing dye molecules in combination with the evaluation of the full shape of the SPR curve, whereby the sensitivity as well as the specificity of SPR is significantly improved. The performance of the new label-enhanced SPR method was demonstrated by two simple model assays: a small molecule assay and a DNA hybridization assay. The small molecule assay was used to demonstrate the sensitivity enhancement of the method, and how competitive assays can be used for relative affinity determination. The DNA assay was used to demonstrate the selectivity of the assay, and the capabilities in eliminating noise from bulk liquid composition variations. PMID:24217357

  11. Per un dizionario della ricerca sul Technology Enhanced Learning

    Directory of Open Access Journals (Sweden)

    Nicolas Balacheff

    2012-12-01

    Full Text Available Questo articolo presenta le principali linee di azione di un meta-progetto iniziato nell’ambito della Rete di Eccellenza STELLAR con l’obiettivo di creare e dare struttura a un Thesaurus e a un Dizionario dei termini e delle espressioni in uso nell’ambito della ricerca sul Technology Enhanced Learning (TEL. Questo meta-progetto intende fornire gli strumenti per superare le difficoltà dovute alla ricchezza e alla rapida evoluzione di quest’area di ricerca multidisciplinare, allo scopo di facilitare il coinvolgimento dei ricercatori giovani e di quelli che si accostano per la prima volta a questo settore, nonché di tutti coloro che a vario titolo si interessano al TEL. Il meta-progetto in questione ha anche l’ambizione di facilitare la comunicazione tra individui appartenenti a diverse culture scientifiche e tra le lingue nazionali. Dopo una presentazione delle motivazioni, vengono discussi gli attuali sviluppi del lavoro e presentati i criteri seguiti per le principali scelte effettuate in merito ai metodi e alle tecnologie utilizzate.

  12. Enhancement of chromate reduction in soils by surface modified biochar.

    Science.gov (United States)

    Mandal, Sanchita; Sarkar, Binoy; Bolan, Nanthi; Ok, Yong Sik; Naidu, Ravi

    2017-01-15

    Chromium (Cr) is one of the common metals present in the soils and may have an extremely deleterious environmental impact depending on its redox state. Among two common forms, trivalent Cr(III) is less toxic than hexavalent Cr(VI) in soils. Carbon (C) based materials including biochar could be used to alleviate Cr toxicity through converting Cr(VI) to Cr(III). Incubation experiments were conducted to examine Cr(VI) reduction in different soils (Soil 1: pH 7.5 and Soil 2: pH 5.5) with three manures from poultry (PM), cow (CM) and sheep (SM), three respective manure-derived biochars (PM biochar (PM-BC), CM biochar (CM-BC) and SM biochar (SM-BC)) and two modified biochars (modified PM-BC (PM-BC-M) and modified SM-BC (SM-BC-M)). Modified biochar was synthesized by incorporating chitosan and zerovalent iron (ZVI) during pyrolysis. Among biochars, highest Cr(VI) reduction was observed with PM-BC application (5%; w/w) (up to 88.12 mg kg(-1); 45% reduction) in Soil 2 (pH 5.5). The modified biochars enhanced Cr(VI) reduction by 55% (SM-BC-M) compared to manure (29%, SM) and manure-derived biochars (40% reduction, SM-BC). Among the modified biochars, SM-BC-M showed a higher Cr(VI) reduction rate (55%) than PM-BC-M (48%) in Soil 2. Various oxygen-containing surface functional groups such as phenolic, carboxyl, carbonyl, etc. on biochar surface might act as a proton donor for Cr(VI) reduction and subsequent Cr(III) adsorption. This study underpins the immense potential of modified biochar in remediation of Cr(VI) contaminated soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. High Sensitivity Surface Enhanced Raman Scattering Detection of Tryptophan

    Science.gov (United States)

    Kandakkathara, Archana

    Raman spectroscopy has the capability of providing detailed information about molecular structure, but the extremely small cross section of Raman scattering prevents this technique from applications requiring high sensitivity. Surface enhanced Raman scattering (SERS) on the other hand provides strongly increased Raman signal from molecules attached to metallic nanostructures. SERS is thus a promising technique for high sensitivity analytical applications. One particular area of interest is the application of such techniques for the analysis of the composition of biological cells. However, there are issues which have to be addressed in order to make SERS a reliable technique such as the optimization of conditions for any given analyte, understanding the kinetic processes of binding of the target molecules to the nanostructures and understanding the evolution and coagulation of the nanostructures, in the case of colloidal solutions. The latter processes introduce a delay time for the observation of maximum enhancement factors which must be taken into account for any given implementation of SERS. In the present thesis the goal was to develop very sensitive SERS techniques for the measurement of biomolecules of interest for analysis of the contents of cells. The techniques explored could be eventually be applicable to microfluidic systems with the ultimate goal of analyzing the molecular constituents of single cells. SERS study of different amino acids and organic dyes were performed during the course of this thesis. A high sensitivity detection system based on SERS has been developed and spectrum from tryptophan (Trp) amino acid at very low concentration (10-8 M) has been detected. The concentration at which good quality SERS spectra could be detected from Trp is 4 orders of magnitude smaller than that previously reported in literature. It has shown that at such low concentrations the SERS spectra of Trp are qualitatively distinct from the spectra commonly reported in

  14. Surface physics of materials materials science and technology

    CERN Document Server

    Blakely, J M

    2013-01-01

    Surface Physics of Materials presents accounts of the physical properties of solid surfaces. The book contains selected articles that deal with research emphasizing surface properties rather than experimental techniques in the field of surface physics. Topics discussed include transport of matter at surfaces; interaction of atoms and molecules with surfaces; chemical analysis of surfaces; and adhesion and friction. Research workers, teachers and graduate students in surface physics, and materials scientist will find the book highly useful.

  15. Surface-enhanced Raman scattering (SERS) study of anthocyanidins

    Science.gov (United States)

    Zaffino, Chiara; Russo, Bianca; Bruni, Silvia

    2015-10-01

    Anthocyanins are an important class of natural compounds responsible for the red, purple and blue colors in a large number of flowers, fruits and cereal grains. They are polyhydroxy- and polymethoxy-derivatives of 2-phenylbenzopyrylium (flavylium) salts, which are present in nature as glycosylated molecules. The aim of the present study is to assess the identification of anthocyanidins, i.e. anthocyanins without the glycosidic moiety, by means of surface-enhanced Raman spectroscopy (SERS), a very chemically-specific technique which is moreover sensitive to subtle changes in molecular structures. These features can lead to elect SERS, among the spectroscopic tools currently at disposal of scientists, as a technique of choice for the identification of anthocyanidins, since: (1) anthocyanidins structurally present the same benzopyrylium moiety and differentiate only for the substitution pattern on their phenyl ring, (2) different species are present in aqueous solution depending on the pH. It will be demonstrated that, while resonance Raman spectra of anthocyanidins are very similar to one another, SER spectra show greater differences, leading to a further step in the identification of such important compounds in diluted solutions by means of vibrational spectroscopy. Moreover, the dependence on the pH of the six most common anthocyanidins, i.e. cyanidin, delphinidin, pelargonidin, peonidin, malvidin and petunidin, is studied. To the best of the authors' knowledge, a complete SERS study of such important molecules is reported in the present work for the first time.

  16. Surface stabilized efavirenz nanoparticles for oral bioavailability enhancement.

    Science.gov (United States)

    Jain, Sanyog; Sharma, Jagadish M; Agrawal, Ashish K; Mahajan, Rahul R

    2013-11-01

    The aim of the present study was to prepare surface stabilized nanoparticles for oral bioavailability enhancement of efavirenz (EFZ). EFZ nanoparticles (EFZ-NPs) were prepared by combination of anti-solvent precipitation and high pressure homogenization technique, using hydroxy propyl methyl cellulose as stabilizer which resulted in formation of EFZ-NPs of average particle size -350 nm with excellent particles size distribution (distribution and drug content. EFZ-NPs demonstrated an increase in saturation solubility by 5.16 folds in comparison with free EFZ. In vitro dissolution studies established advantage of EFZ-NPs over free EFZ as more than 75% drug was dissolved within 5 min in case of EFZ-NPs while it was approx 20% in case of free EFZ. In vivo pharmacokinetic studies further confirmed the potential of EFZ-NPs as 2.02 folds increase in peak plasma concentration and 2.29 folds increase in AUC(0-infinity) were observed in comparison to free EFZ. The In vitro-In vivo relationship of the formulations further suggested higher correlation coefficient of 0.9995 for EFZ-NPs in Levys plot as compared to 0.8726 for free EFZ.

  17. Surface plasmon resonance prism coupler for enhanced circular dichroism sensing.

    Science.gov (United States)

    Phan, Quoc-Hung; Lo, Yu-Lung; Huang, Chih-Ling

    2016-06-13

    A novel method for enhanced circular dichroism (CD) detection is proposed based on a surface plasmon resonance (SPR) prism coupler and a polarization scanning ellipsometry technique. An analytical model is derived to extract the CD and degree of polarization (DOP) properties of optical samples with and without scattering effects, respectively. The validity of the analytical model is confirmed by means of numerical simulations. The simulation results show that the proposed detection method has a sensitivity of 10-5~10-6 RIU (refractive index unit) for refractive indices in the range of 1.32~1.36 and 1.3100~1.3118. The practical feasibility of the proposed method is demonstrated by the experimental results for the sensitivity of the CD with the chlorophyllin samples with/without scattering effect. It is shown that for both types of sample, the extracted CD value increases linearly with the chlorophyll concentration over the considered range. In general, the results obtained in this study show that the measured CD response is highly sensitive to the polarization scanning angle. Consequently, the potential of polarization scanning ellipsometry for high-resolution CD detection is confirmed.

  18. Spectroscopic fingerprint of tea varieties by surface enhanced Raman spectroscopy.

    Science.gov (United States)

    Buyukgoz, Guluzar Gorkem; Soforoglu, Mehmet; Basaran Akgul, Nese; Boyaci, Ismail Hakki

    2016-03-01

    The fingerprinting method is generally performed to determine specific molecules or the behavior of specific molecular bonds in the desired sample content. A novel, robust and simple method based on surface enhanced Raman spectroscopy (SERS) was developed to obtain the full spectrum of tea varieties for detection of the purity of the samples based on the type of processing and cultivation. For this purpose, the fingerprint of seven different varieties of tea samples (herbal tea (rose hip, chamomile, linden, green and sage tea), black tea and earl grey tea) combined with silver colloids was obtained by SERS in the range of 200-2000 cm(-1) with an analysis time of 20 s. Each of the thirty-nine tea samples tested showed its own specific SERS spectra. Principal Component Analysis (PCA) was also applied to separate of each tea variety and different models developed for tea samples including three different models for the herbal teas and two different models for black and earl grey tea samples. Herbal tea samples were separated using mean centering, smoothing and median centering pre-processing steps while baselining and derivatisation pre-processing steps were applied to SERS data of black and earl grey tea. The novel spectroscopic fingerprinting technique combined with PCA is an accurate, rapid and simple methodology for the assessment of tea types based on the type of processing and cultivation differences. This method is proposed as an alternative tool in order to determine the characteristics of tea varieties.

  19. Digital innovations and emerging technologies for enhanced recovery programmes.

    Science.gov (United States)

    Michard, F; Gan, T J; Kehlet, H

    2017-07-01

    Enhanced recovery programmes (ERPs) are increasingly used to improve post-surgical recovery. However, compliance to various components of ERPs-a key determinant of success-remains sub-optimal. Emerging technologies have the potential to help patients and caregivers to improve compliance with ERPs.Preoperative physical condition, a major determinant of postoperative outcome, could be optimized with the use of text messages (SMS) or digital applications (Apps) designed to facilitate smoking cessation, modify physical activity, and better manage hypertension and diabetes. Several non-invasive haemodynamic monitoring techniques and decision support tools are now available to individualize perioperative fluid management, a key component of ERPs. Objective nociceptive assessment may help to rationalize the use of pain medications, including opioids. Wearable sensors designed to monitor cardio-respiratory function may help in the early detection of clinical deterioration during the postoperative recovery and to address 'failure to rescue'. Activity trackers may be useful to monitor early mobilization, another major element of ERPs. Finally, electronic checklists have been developed to ensure that none of the above-mentioned ERP elements is omitted during the surgical journey.By optimizing compliance to the multiple components of ERPs, digital innovations, non-invasive techniques and wearable sensors have the potential to magnify the clinical and economic benefits of ERPs. Among the growing number of technical innovations, studies are needed to clarify which tools and solutions have real clinical value and are cost-effective. © The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Progress in Bacillus subtilis Spore Surface Display Technology towards Environment, Vaccine Development, and Biocatalysis.

    Science.gov (United States)

    Chen, Huayou; Ullah, Jawad; Jia, Jinru

    2017-01-01

    Spore surface display is the most desirable with enhanced effects, low cost, less time consuming and the most promising technology for environmental, medical, and industrial development. Spores have various applications in industry due to their ability to survive in harsh industrial processes including heat resistance, alkaline tolerance, chemical tolerance, easy recovery, and reusability. Yeast and bacteria, including gram-positive and -negative, are the most frequently used organisms for the display of various proteins (eukaryotic and prokaryotic), but unlike spores, they can rupture easily due to nutritive properties, susceptibility to heat, pH, and chemicals. Hence, spores are the best choice to avoid these problems, and they have various applications over nonspore formers due to amenability for laboratory purposes. Various strains of Clostridium and Bacillus are spore formers, but the most suitable choice for display is Bacillus subtilis because, according to the WHO, it is safe to humans and considered as "GRAS" (generally recognized as safe). This review focuses on the application of spore surface display towards industries, vaccine development, the environment, and peptide library construction, with cell surface display for enhanced protein expression and high enzymatic activity. Different vectors, coat proteins, and statistical analyses can be used for linker selection to obtain greater expression and high activity of the displayed protein. © 2017 S. Karger AG, Basel.

  1. Using Technology-Nested Instructional Strategies to Enhance Student Learning

    Science.gov (United States)

    Lumpkin, Angela; Achen, Rebecca M.; Dodd, Regan K.

    2015-01-01

    Students today expect the use of technology in their classes, rather than have to listen to less-than-engaging lectures. College students are connected electronically and incessant technology consumers. As a result, they may prefer the infusion of technologies to help them learn and enjoy the process of learning, rather than having to listen…

  2. Patterning of Biomolecules on Plasma-Enhanced Chemical Vapor Deposited Generated Surfaces

    National Research Council Canada - National Science Library

    Slocik, Joseph M; Beckel, Eric R; Jiang, Hao; Enlow, Jesse O; Zabinsky, Jr., Jeffrey S; Bunning, Timothy J; Naika, Rajesh R

    2006-01-01

    Micropatterned surfaces have received extensive attention for possible applications in advanced technologies including microelectronics, microfluidics, cell growth confinement and biosensor fabrication...

  3. Proceedings of the 2nd Workshop on Awareness and Reflection in Technology-Enhanced Learning

    NARCIS (Netherlands)

    Moore, Adam; Pammer, Viktoria; Pannese, Lucia; Prilla, Michael; Rajagopal, Kamakshi; Reinhardt, Wolfgang; Ullman, Thomas; Voigt, Christian

    2013-01-01

    Moore, A., Pammer, V., Pannese, L., Prilla, M., Rajagopal, K., Reinhardt, W., Ullman, Th. D., & Voigt, Ch. (Eds.) (2012). Proceedings of the 2nd Workshop on Awareness and Reflection in Technology Enhanced Learning. In conjunction with the 7th European Conference on Technology Enhanced Learning: 21st

  4. Social network analysis for technology-enhanced learning: review and future directions

    NARCIS (Netherlands)

    Sie, Rory; Ullmann, Thomas; Rajagopal, Kamakshi; Cela, Karina; Bitter-Rijpkema, Marlies; Sloep, Peter

    2013-01-01

    Sie, R. L. L., Ullmann, T. D., Rajagopal, K., Cela, K., Bitter-Rijpkema, M., & Sloep, P. B. (2012). Social network analysis for technology-enhanced learning: review and future directions. International Journal of Technology Enhanced Learning, 4(3/4), 172-190.

  5. Theoretical and practical aspects of self-regulated learning in technology enhanced preschools and primary classrooms

    NARCIS (Netherlands)

    Mooij, Ton

    2012-01-01

    Mooij, T. (2012, 20 September). Theoretical and practical aspects of self-regulated learning in technology enhanced preschools and primary classrooms. Invited presentation for the symposion Self-regulated learning in technology enhanced learning environments at the ‘European Conference on

  6. A microfluidic surface enhanced Raman spectroscopic biosensor using aptamer functionalized nanopillars

    DEFF Research Database (Denmark)

    Yang, J.; Palla, M.; Bosco, F. G.

    2013-01-01

    This paper presents a microchip incorporating an aptamer-functionalized nanopillar substrate, enabling the specific detection of low-abundance biomolecules using surface enhanced Raman spectroscopy (SERS). In a temperature controlled microchamber, aptamers immobilized on the nanostructure surface...

  7. Determination of antimony by surface-enhanced Raman spectroscopy.

    Science.gov (United States)

    Panarin, Andrei Yu; Khodasevich, Inna A; Gladkova, Olga L; Terekhov, Sergei N

    2014-01-01

    A highly sensitive method for the detection and quantitative evaluation of antimony(III) using the surface-enhanced Raman scattering (SERS) technique is demonstrated. The method is based on the analysis of SERS spectra intensity of antimony bound to phenylfluorone (Sb-PhF). Phenylfluorone is widely used as an organic reagent for the spectrophotometric determination of some heavy metals. For the SERS experiment a Sb-PhF complex was adsorbed onto the silvered porous silicon substrate. The significant degradation of the SERS signal was observed during measurements in the air. The time evolution of SERS spectra at ambient and degassed conditions was investigated to find an optimal regime for SERS measurements. The limit of Sb detection in degassed samples was determined to be near 1 ng/mL, which is one order of magnitude less than that attainable by the photometric approach. The linear range of the method to Sb(III) was found to a mass concentration range of 1-10 ng/mL. This approach permits an absolute quantity of Sb(III) to be detected at the picogram level (∼50 pg). It is remarkable that a very small sample volume (50 μL) is required for SERS analysis. Moreover this technique offers high selectivity owing to the distinctive vibrational features for the metallorganic complex and to the resonance character of Raman spectra. The proposed SERS-based detection of Sb is a fast and highly sensitive method for use in environmental and industrial waste monitoring as well as for forensic science to determine gunshot residue. We expect that the approach reported herein can be further extended to develop new detection techniques for other heavy metals.

  8. Enhanced Modeling of Remotely Sensed Annual Land Surface Temperature Cycle

    Science.gov (United States)

    Zou, Z.; Zhan, W.; Jiang, L.

    2017-09-01

    Satellite thermal remote sensing provides access to acquire large-scale Land surface temperature (LST) data, but also generates missing and abnormal values resulting from non-clear-sky conditions. Given this limitation, Annual Temperature Cycle (ATC) model was employed to reconstruct the continuous daily LST data over a year. The original model ATCO used harmonic functions, but the dramatic changes of the real LST caused by the weather changes remained unclear due to the smooth sine curve. Using Aqua/MODIS LST products, NDVI and meteorological data, we proposed enhanced model ATCE based on ATCO to describe the fluctuation and compared their performances for the Yangtze River Delta region of China. The results demonstrated that, the overall root mean square errors (RMSEs) of the ATCE was lower than ATCO, and the improved accuracy of daytime was better than that of night, with the errors decreased by 0.64 K and 0.36 K, respectively. The improvements of accuracies varied with different land cover types: the forest, grassland and built-up areas improved larger than water. And the spatial heterogeneity was observed for performance of ATC model: the RMSEs of built-up area, forest and grassland were around 3.0 K in the daytime, while the water attained 2.27 K; at night, the accuracies of all types significantly increased to similar RMSEs level about 2 K. By comparing the differences between LSTs simulated by two models in different seasons, it was found that the differences were smaller in the spring and autumn, while larger in the summer and winter.

  9. Localized surface plasmon enhanced cellular imaging using random metallic structures

    Science.gov (United States)

    Son, Taehwang; Lee, Wonju; Kim, Donghyun

    2017-02-01

    We have studied fluorescence cellular imaging with randomly distributed localized near-field induced by silver nano-islands. For the fabrication of nano-islands, a 10-nm silver thin film evaporated on a BK7 glass substrate with an adhesion layer of 2-nm thick chromium. Micrometer sized silver square pattern was defined using e-beam lithography and then the film was annealed at 200°C. Raw images were restored using electric field distribution produced on the surface of random nano-islands. Nano-islands were modeled from SEM images. 488-nm p-polarized light source was set to be incident at 60°. Simulation results show that localized electric fields were created among nano-islands and that their average size was found to be 135 nm. The feasibility was tested using conventional total internal reflection fluorescence microscopy while the angle of incidence was adjusted to maximize field enhancement. Mouse microphage cells were cultured on nano-islands, and actin filaments were selectively stained with FITC-conjugated phalloidin. Acquired images were deconvolved based on linear imaging theory, in which molecular distribution was sampled by randomly distributed localized near-field and blurred by point spread function of far-field optics. The optimum fluorophore distribution was probabilistically estimated by repetitively matching a raw image. The deconvolved images are estimated to have a resolution in the range of 100-150 nm largely determined by the size of localized near-fields. We also discuss and compare the results with images acquired with periodic nano-aperture arrays in various optical configurations to excite localized plasmonic fields and to produce super-resolved molecular images.

  10. G-Protein Coupled Receptors: Surface Display and Biosensor Technology

    Science.gov (United States)

    McMurchie, Edward; Leifert, Wayne

    Signal transduction by G-protein coupled receptors (GPCRs) underpins a multitude of physiological processes. Ligand recognition by the receptor leads to the activation of a generic molecular switch involving heterotrimeric G-proteins and guanine nucleotides. With growing interest and commercial investment in GPCRs in areas such as drug targets, orphan receptors, high-throughput screening of drugs and biosensors, greater attention will focus on assay development to allow for miniaturization, ultrahigh-throughput and, eventually, microarray/biochip assay formats that will require nanotechnology-based approaches. Stable, robust, cell-free signaling assemblies comprising receptor and appropriate molecular switching components will form the basis of future GPCR/G-protein platforms, which should be able to be adapted to such applications as microarrays and biosensors. This chapter focuses on cell-free GPCR assay nanotechnologies and describes some molecular biological approaches for the construction of more sophisticated, surface-immobilized, homogeneous, functional GPCR sensors. The latter points should greatly extend the range of applications to which technologies based on GPCRs could be applied.

  11. Enhanced Thermal Transport of Surfaces with Superhydrophobic Coatings

    Science.gov (United States)

    2015-07-01

    water droplets placed on the surface of the lotus leaf is 160°.1 Superhydrophobic surfaces have potential applications in self-cleaning surfaces,2...modified from a hydrophilic chemistry (oxide) to a hydrophobic surface using a fluorinated (or protonated) self-assembled monolayer (SAM). Chemical...to be less than 170°. In a separate experiment, a polished Cu pipe was treated with hydrochloric acid, silver nitrate, and fluorinated SAM as above

  12. Technology-Enhanced Mathematics Education for Creative Engineering Studies

    DEFF Research Database (Denmark)

    Triantafyllou, Eva; Timcenko, Olga

    2014-01-01

    This project explores the opportunities and challenges of integrating digital technologies in mathematics education in creative engineering studies. Students in such studies lack motivation and do not perceive the mathematics the same way as mathematics students do. Digital technologies offer new...... are conceptualized. Then, we are going to apply this field data in designing learning technologies, which will be introduced in university classrooms. The effect of this introduction will be evaluated through educational design experiments....

  13. Amplification of Surface-Enhanced Raman Scattering Due to Substrate-Mediated Localized Surface Plasmons in Gold Nanodimers

    KAUST Repository

    Yue, Weisheng

    2017-03-28

    Surface-enhanced Raman scattering (SERS) is ubiquitous in chemical and biochemical sensing, imaging and identification. Maximizing SERS enhancement is a continuous effort focused on the design of appropriate SERS substrates. Here we show that significant improvement in a SERS signal can be achieved with substrates combining localized surface plasmon resonances and a nonresonant plasmonic substrate. By introducing a continuous gold (Au) film underneath Au nanodimers antenna arrays, an over 10-fold increase in SERS enhancement is demonstrated. Triangular, rectangle and disc dimers were studied, with bowtie antenna providing highest SERS enhancement. Simulations of electromagnetic field distributions of the Au nanodimers on the Au film support the observed enhancement dependences. The hybridization of localized plasmonic modes with the image modes in a metal film provides a straightforward way to improve SERS enhancement in designer SERS substrate.

  14. What Do Students Want? Making Sense of Student Preferences in Technology-Enhanced Learning

    Science.gov (United States)

    Pechenkina, Ekaterina; Aeschliman, Carol

    2017-01-01

    This article, with its focus on university students as intended recipients and users of technological innovations in education, explores student preferences across three dimensions of technology-enhanced learning: mode of instruction; communication; and educational technology tools embedded in learning and teaching activities. The article draws on…

  15. Control technology for surface treatment of materials using induction hardening

    Energy Technology Data Exchange (ETDEWEB)

    Kelley, J.B.; Skocypec, R.D. [Sandia National Labs., NM (United States)

    1997-04-01

    In the industrial and automotive industries, induction case hardening is widely used to provide enhanced strength, wear resistance, and toughness in components made from medium and high carbon steels. The process uses significantly less energy than competing batch process, is environmentally benign, and is a very flexible in-line manufacturing process. As such, it can directly contribute to improved component reliability, and the manufacture of high-performance lightweight parts. However, induction hardening is not as widely used as it could be. Input material and unexplained process variations produce significant variation in product case depth and quality. This necessitates frequent inspection of product quality by destructive examination, creates higher than desired scrap rates, and causes de-rating of load stress sensitive components. In addition, process and tooling development are experience-based activities, accomplished by trial and error. This inhibits the use of induction hardening for new applications, and the resultant increase in energy efficiency in the industrial sectors. In FY96, a Cooperative Research and Development Agreement under the auspices of the Technology Transfer Initiative and the Partnership for a New Generation of Vehicles was completed. A multidisciplinary team from Sandia National Labs and Delphi Saginaw Steering Systems investigated the induction hardening by conducting research in the areas of process characterization, computational modeling, materials characterization, and high speed data acquisition and controller development. The goal was to demonstrate the feasibility of closed-loop control for a specific material, geometry, and process. Delphi Steering estimated annual savings of $2-3 million per year due to reduced scrap losses, inspection costs, and machine down time if reliable closed-loop control could be achieved. A factor of five improvement in process precision was demonstrated and is now operational on the factory floor.

  16. Fission Surface Power Technology Demonstration Unit Test Results

    Science.gov (United States)

    Briggs, Maxwell H.; Gibson, Marc A.; Geng, Steven M.; Sanzi, James L.

    2016-01-01

    The Fission Surface Power (FSP) Technology Demonstration Unit (TDU) is a system-level demonstration of fission power technology intended for use on manned missions to Mars. The Baseline FSP systems consists of a 190 kWt UO2 fast-spectrum reactor cooled by a primary pumped liquid metal loop. This liquid metal loop transfers heat to two intermediate liquid metal loops designed to isolate fission products in the primary loop from the balance of plant. The intermediate liquid metal loops transfer heat to four Stirling Power Conversion Units (PCU), each of which produce 12 kWe (48 kW total) and reject waste heat to two pumped water loops, which transfer the waste heat to titanium-water heat pipe radiators. The FSP TDU simulates a single leg of the baseline FSP system using an electrically heater core simulator, a single liquid metal loop, a single PCU, and a pumped water loop which rejects the waste heat to a Facility Cooling System (FCS). When operated at the nominal operating conditions (modified for low liquid metal flow) during TDU testing the PCU produced 8.9 kW of power at an efficiency of 21.7 percent resulting in a net system power of 8.1 kW and a system level efficiency of 17.2 percent. The reduction in PCU power from levels seen during electrically heated testing is the result of insufficient heat transfer from the NaK heater head to the Stirling acceptor, which could not be tested at Sunpower prior to delivery to the NASA Glenn Research Center (GRC). The maximum PCU power of 10.4 kW was achieved at the maximum liquid metal temperature of 875 K, minimum water temperature of 350 K, 1.1 kg/s liquid metal flow, 0.39 kg/s water flow, and 15.0 mm amplitude at an efficiency of 23.3 percent. This resulted in a system net power of 9.7 kW and a system efficiency of 18.7 percent.

  17. Study on nasopharyngeal cancer tissue using surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Ge, Xiaosong; Lin, Xueliang; Xu, Zhihong; Wei, Guoqiang; Huang, Wei; Lin, Duo

    2016-10-01

    Surface-enhanced Raman spectroscopy (SERS) can provide detailed molecular structure and composition information, and has demonstrated great potential in biomedical filed. This spectroscopy technology has become one of the most important optical techniques in the early diagnosis of cancer. Nasopharyngeal cancer (NPC) is a malignant neoplasm arising in the nasopharyngeal epithelial lining, which has relatively high incidence and death rate in Southeast Asia and southern China. This paper reviews the current progress of SERS in the field of cancer diagnostics, including gastric cancer, colorectal cancer, cervical cancer and nasopharyngeal cancer. In addition to above researches, we recently develop a novel NPC detection method based on tissue section using SERS, and obtain primary results. The proposed method has promising potential for the detection of nasopharyngeal carcinoma.

  18. Is Increasing Our Reliance on Technology Enhancing Education?

    Science.gov (United States)

    Sorensen, Andrew A.; Snider, John C.

    2001-01-01

    Analyzes the relationship between megatrends (technology, demographics, globalization, branding, consolidation, outsourcing) and use of technology in higher education. Considers how the university's historic mission is eroding and suggests possibilities for both a commitment to that mission and use of high-tech distance learning in the global…

  19. A Case Study of Technology-Enhanced Historical Inquiry

    Science.gov (United States)

    Yang, Shu Ching

    2009-01-01

    The paper describes the integration of web resources and technology as instructional and learning tools in oral history projects. The computer-mediated oral history project centred around interviews with community elders combined with new technologies to engage students in authentic historical inquiry. The study examined learners' affective…

  20. Uniting Legislation with RFID Privacy-Enhancing Technologies

    NARCIS (Netherlands)

    Rieback, M.R.; Crispo, B.; Tanenbaum, A.S.

    2005-01-01

    RFID is a popular identification and automation technology with serious security and privacy threats. Legislation expounds upon the actual security and privacy needs of people in RFID-enabled environments, while technology helps to ensure legal compliance. This paper examines the main aims of RFID

  1. Technology for enhancing statistical reasoning at the school level

    NARCIS (Netherlands)

    Biehler, R.; Ben-Zvi, D.; Bakker, A.; Makar, K.

    2013-01-01

    The purpose of this chapter is to provide an updated overview of digital technologies relevant to statistics education, and to summarize what is currently known about how these new technologies can support the development of students’ statistical reasoning at the school level. A brief literature

  2. LEVERAGING TECHNOLOGY TO ENHANCE ADDICTION TREATMENT AND RECOVERY

    Science.gov (United States)

    Marsch, Lisa A.

    2012-01-01

    Technology such as the Internet and mobile phones offers considerable promise for affecting the assessment, prevention, and treatment of and recovery from substance use disorders. Technology may enable entirely new models of behavioral health care within and outside of formal systems of care. This article reviews the promise of technology-based therapeutic tools for affecting the quality and reach of addiction treatment and recovery support systems, as well as the empirical support to date for this approach. Potential models for implementing technology-based interventions targeting substance use disorders are described. Opportunities to optimize the effectiveness and impact of technology-based interventions targeting addiction and recovery, along with outstanding research needs, are discussed. PMID:22873192

  3. Leveraging technology to enhance addiction treatment and recovery.

    Science.gov (United States)

    Marsch, Lisa A

    2012-01-01

    Technology such as the Internet and mobile phones offers considerable promise for affecting the assessment, prevention, and treatment of and recovery from substance use disorders. Technology may enable entirely new models of behavioral health care within and outside of formal systems of care. This article reviews the promise of technology-based therapeutic tools for affecting the quality and reach of addiction treatment and recovery support systems, as well as the empirical support to date for this approach. Potential models for implementing technology-based interventions targeting substance use disorders are described. Opportunities to optimize the effectiveness and impact of technology-based interventions targeting addiction and recovery, along with outstanding research needs, are discussed.

  4. Using Technology-Nested Instructional Strategies to Enhance Student Learning

    Directory of Open Access Journals (Sweden)

    Angela Lumpkin, PhD

    2015-08-01

    Full Text Available Students today expect the use of technology in their classes, rather than have to listen to less-than-engaging lectures. College students are connected electronically and incessant technology consumers. As a result, they may prefer the infusion of technologies to help them learn and enjoy the process of learning, rather than having to listen exclusively to lectures. To investigate this, the authors solicited student perceptions to assess the importance of learning through technology-nested instructional strategies. Student perceptions give direction to and affirm the benefits of instructional strategies that increase student motivation to engage more actively in their learning. Based on quantitative and qualitative responses through action research in multiple courses, students perceive their learning as more engaging and enjoyable when technology-nested instructional strategies are infused into their classes.

  5. Development of New Materials and Technologies for Welding and Surfacing at Research and Production Center "Welding Processes and Technologies"

    Science.gov (United States)

    Kozyrev, N. A.; Kryukov, R. E.; Galevsky, G. V.; Titov, D. A.; Shurupov, V. M.

    2015-09-01

    The paper provides description of research into the influence of new materials and technologies on quality parameters of welds and added metal carried out at research and production center «Welding processes and technologies». New welding technologies of tanks for northern conditions are considered, as well as technologies of submerged arc welding involving fluxing agents AN - 348, AN - 60, AN - 67, OK. 10.71 and carbon-fluorine containing additives, new flux cored wires and surfacing technologies, teaching programs and a trainer for welders are designed.

  6. 77 FR 12227 - Long Term 2 Enhanced Surface Water Treatment Rule: Uncovered Finished Water Reservoirs; Public...

    Science.gov (United States)

    2012-02-29

    ... AGENCY 40 CFR Parts 141 and 142 Long Term 2 Enhanced Surface Water Treatment Rule: Uncovered Finished Water Reservoirs; Public Meeting AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of public... requirement in the Long Term 2 Enhanced Surface Water Treatment Rule (LT2 rule). At this meeting, EPA will...

  7. Enhancement of spontaneous recombination rate in a quantum well by resonant surface plasmon coupling

    Science.gov (United States)

    Neogi, Arup; Lee, Chang-Won; Everitt, Henry O.; Kuroda, Takamasa; Tackeuchi, Atsushi; Yablonovitch, Eli

    2002-10-01

    Using time-resolved photoluminescence measurements, the recombination rate in an In0.18Ga0.82N/GaN quantum well (QW) is shown to be greatly enhanced when spontaneous emission is resonantly coupled to a silver surface plasmon. The rate of enhanced spontaneous emission into the surface plasmon was as much as 92 times faster than QW spontaneous emission into free space. A calculation, based on Fermi's golden rule, reveals that the enhancement is very sensitive to silver thickness and indicates even greater enhancements are possible for QW's placed closer to the surface metal coating.

  8. Design of Ag nanorods for sensitivity and thermal stability of surface-enhanced Raman scattering

    Science.gov (United States)

    Ma, Lingwei; Zhang, Zhengjun; Huang, Hanchen

    2017-10-01

    The technology of surface-enhanced Raman scattering (SERS) has found many applications and may find more if it can possess both sensitivity and thermal stability. This paper reports a rational design of Ag nanorods to simultaneously achieve two competing goals: the sensitivity and the thermal stability of SERS substrates. The Ag nanorods are designed and synthesized using physical vapor deposition under the condition of glancing angle incidence. The working pressure of the vacuum chamber is controlled so the mean free path of depositing atoms is comparable to the dimension of the chamber, so as to grow Ag nanorods with small diameter, and small but clear separation for optimal SERS sensitivity. Such Ag nanorods are further capped with Al2O3 on their top surfaces to reduce the diffusion-induced coarsening at high temperatures, and thereby to improve the thermal stability for SERS detections. Meanwhile, since the side surfaces of Ag nanorods are not coated with oxides in this approach, the SERS sensitivity is largely preserved while good thermal stability is achieved.

  9. Laser microtexturing of implant surfaces for enhanced tissue integration

    Energy Technology Data Exchange (ETDEWEB)

    Ricci, J.L. [Univ. of Medicine and Dentistry of New Jersey, Newark, NJ (United States). Dept. of Orthodontics; Alexander, H. [Orthogen Corp., Springfield, NJ (United States)

    2001-07-01

    The success or failure of bone and soft tissue-fixed medical devices, such as dental and orthopaedic implants, depends on a complex combination of biological and mechanical factors. These factors are intimately associated with the interface between the implant surface and the surrounding tissue, and are largely determined by the composition, surface chemistry, and surface microgeometry of the implant. The relative contributions of these factors are difficult to assess. This study addresses the contribution of surface microtexture, on a controlled level, to tissue integration. (orig.)

  10. Understanding enhanced tourist experiences through technology: a brief approach to the Vilnius case

    Directory of Open Access Journals (Sweden)

    Ilona Beliatskaya

    2017-11-01

    Full Text Available The present research investigates the notion of enhanced tourist experiences through technology shedding light on co-creation practices and empowerment of customers. Neuhofer and Buhalis (2013 introduced a novel concept of technology-enhanced tourist experiences by generating a joint comprehension of new era of experiences which conjoin the elements of experiences, co-creation and technology. Being one of rather promoting cities in online environment Vilnius represents an interesting case of successive adoption of smart technologies in order to enhance tourist experiences and facilitate customer empowerment in Vilnius tourism domain. This study aims to determine technology-enhanced tourist experiences in order to measure factors of customer empowerment on the example of international incoming tourists to Vilnius (Lithuania. The mix-methods approach (qualitative online content and functionality analysis and quantitative survey was justified as being the most appropriate for the purpose of this research with intention to find a basis for applying of technology-enhanced tourist experiences in Vilnius tourism marketplace. The paper concludes with the definition of current level of ICTs application to enhance tourist experience co-creation and a discussion of practical implications of technology-enhanced tourist experiences development.

  11. Human Enhancement Technologies. Verso nuovi modelli antropologici Parte II

    Directory of Open Access Journals (Sweden)

    Luca Lo Sapio

    2013-06-01

    Full Text Available This paper tries to furnish some arguments against the dichotomical approach to human enhancement debate. In particular we flash out the major shortcomings of bioconservative perspective together with the principle criticalities of transhumanist point of view. We aim at delineating a different way of theorizing human enhancement topic pointing out the main results associated with the findings of current scientific research. Our thesis is that we ought to look at human enhancement within a conceptual framework which includes hybridization, openness to alterity, overcoming of nature/culture dichotomy.

  12. Using Social Media Technologies to Enhance Online Learning

    Directory of Open Access Journals (Sweden)

    Hershey H. Friedman

    2013-01-01

    Full Text Available Models of distance education have evolved over decades, just in time to collide with modern pedagogies in which communication, interaction, student engagement, and active learning are of critical importance. The number of college students taking online classes continues to grow. Today, nearly 30% of college students are taking at least one online class. The social media technologies encompass a wide variety of Web-based technologies such as blogs, wikis, online social networking, and virtual worlds. This paper examines the relevant published literature, looking at online learning activities through the prism of the defining characteristics of today’s new communication technologies.

  13. Surface enhanced Raman spectroscopic substrate utilizing gold nanoparticles on carbon nanotubes

    Science.gov (United States)

    Basu, Srismrita; Maulik, Subhodip; Hou, Hsuan-Chao; Daniels-Race, Theda; Feldman, Martin

    2017-11-01

    This paper reports a new low cost technique for fabricating Surface Enhanced Raman Spectroscopy substrates. A Gold (Au) nano-metallic structure for surface enhancement is created by depositing Au nanoparticles on a Multi-wall Carbon Nanotube layer previously deposited on the etched Aluminum foil. A low cost, simple method is used to deposit the nanotubes. Huge enhancements have been observed in both in vitro and in vivo measurements.

  14. Safety Enhancement Technologies for Airport Ramp Area Operations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has been involved in developing advanced automation systems for improving the efficiency of air-traffic operations, reducing controller workload and enhancing...

  15. Surface wettability of silicon substrates enhanced by laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Shih-Feng [National Applied Research Laboratories, Instrument Technology Research Center, Hsinchu (China); National Chiao Tung University, Department of Mechanical Engineering, Hsinchu (China); Hsiao, Wen-Tse; Huang, Kuo-Cheng; Hsiao, Sheng-Yi [National Applied Research Laboratories, Instrument Technology Research Center, Hsinchu (China); Chen, Ming-Fei [National Changhua University of Education, Department of Mechatronics Engineering, Changhua (China); Lin, Yung-Sheng [Hungkuang University, Department of Applied Cosmetology and Graduate Institute of Cosmetic Science, Taichung (China); Chou, Chang-Pin [National Chiao Tung University, Department of Mechanical Engineering, Hsinchu (China)

    2010-11-15

    Laser-ablation techniques have been widely applied for removing material from a solid surface using a laser-beam irradiating apparatus. This paper presents a surface-texturing technique to create rough patterns on a silicon substrate using a pulsed Nd:YAG laser system. The different degrees of microstructure and surface roughness were adjusted by the laser fluence and laser pulse duration. A scanning electron microscope (SEM) and a 3D confocal laser-scanning microscope are used to measure the surface micrograph and roughness of the patterns, respectively. The contact angle variations between droplets on the textured surface were measured using an FTA 188 video contact angle analyzer. The results indicate that increasing the values of laser fluence and laser pulse duration pushes more molten slag piled around these patterns to create micro-sized craters and leads to an increase in the crater height and surface roughness. A typical example of a droplet on a laser-textured surface shows that the droplet spreads very quickly and almost disappears within 0.5167 s, compared to a contact angle of 47.9 on an untextured surface. This processing technique can also be applied to fabricating Si solar panels to increase the absorption efficiency of light. (orig.)

  16. Technology Advancements Enhance Aircraft Support of Experiment Campaigns

    Science.gov (United States)

    Vachon, Jacques J.

    2009-01-01

    For over 30 years, the NASA Airborne Science Program has provided airborne platforms for space bound instrument development, for calibrating new and existing satellite systems, and for making in situ and remote sensing measurements that can only be made from aircraft. New technologies have expanded the capabilities of aircraft that are operated for these missions. Over the last several years a new technology investment portfolio has yielded improvements that produce better measurements for the airborne science communities. These new technologies include unmanned vehicles, precision trajectory control and advanced telecommunications capabilities. We will discuss some of the benefits of these new technologies and systems which aim to provide users with more precision, lower operational costs, quicker access to data, and better management of multi aircraft and multi sensor campaigns.

  17. Enhanced Performance of Recycled Aggregate Concrete with Atomic Polymer Technology

    Science.gov (United States)

    2012-06-01

    The atomic polymer technology in form of mesoporous inorganic polymer (MIP) can effectively improve material durability and performance of concrete by dramatically increase inter/intragranular bond strength of concrete at nano-scale. The strategy of ...

  18. Utilizing technological innovations to enhance psychotherapy supervision, training, and outcomes.

    Science.gov (United States)

    Barnett, Jeffrey E

    2011-06-01

    Recent technological advances in the use of the Internet and video technologies has greatly impacted the provision of psychotherapy and other clinical services as well as how the training of psychotherapists may be conducted. When utilized appropriately these technologies may provide greater access to needed services to include treatment, consultation, supervision, and training. Specific ethical challenges and pitfalls are discussed and recommendations are made for the ethical use of these technologies. Additionally, innovative practices from the seven articles in the special section that follows are highlighted and reviewed. These articles present a number of innovations that can take psychotherapy training, research, supervision, and treatment forward toward increased effectiveness. Recommendations for integrating these innovations into ongoing practices are provided and for additional research to build on the important work of the authors in this special section are provided.

  19. The Nanofabrication and Application of Substrates for Surface-Enhanced Raman Scattering

    Directory of Open Access Journals (Sweden)

    Xian Zhang

    2012-01-01

    Full Text Available Surface-enhanced Raman scattering (SERS was discovered in 1974 and impacted Raman spectroscopy and surface science. Although SERS has not been developed to be an applicable detection tool so far, nanotechnology has promoted its development in recent decades. The traditional SERS substrates, such as silver electrode, metal island film, and silver colloid, cannot be applied because of their enhancement factor or stability, but newly developed substrates, such as electrochemical deposition surface, Ag porous film, and surface-confined colloids, have better sensitivity and stability. Surface enhanced Raman scattering is applied in other fields such as detection of chemical pollutant, biomolecules, DNA, bacteria, and so forth. In this paper, the development of nanofabrication and application of surface-enhanced Ramans scattering substrate are discussed.

  20. 3D medical collaboration technology to enhance emergency healthcare

    DEFF Research Database (Denmark)

    Welch, Gregory F; Sonnenwald, Diane H.; Fuchs, Henry

    2009-01-01

    of the dynamic reconstructions. We call this idea remote 3D medical collaboration. In this article we motivate and explain the vision for 3D medical collaboration technology; we describe the relevant computer vision, computer graphics, display, and networking research; we present a proof-of-concept prototype...... system; and we present evaluation results supporting the general hypothesis that 3D remote medical collaboration technology could offer benefits over conventional 2D videoconferencing in emergency healthcare....

  1. Biomimetic surface modification of polypropylene by surface chain transfer reaction based on mussel-inspired adhesion technology and thiol chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Zhijun; Zhao, Yang; Sun, Wei; Shi, Suqing, E-mail: shisq@nwu.edu.cn; Gong, Yongkuan

    2016-11-15

    Highlights: • Biomimetic surface modification of PP was successfully conducted by integrating mussel-inspired technology, thiol chemistry and cell outer membranes-like structures. • The resultant biomimetic surface exhibits good interface and surface stability. • The obvious suppression of protein adsorption and platelet adhesion is also achieved. • The residue thoil groups on the surface could be further functionalized. - Abstract: Biomimetic surface modification of polypropylene (PP) is conducted by surface chain transfer reaction based on the mussel-inspired versatile adhesion technology and thiol chemistry, using 2-methacryloyloxyethylphosphorylcholine (MPC) as a hydrophilic monomer mimicking the cell outer membrane structure and 2,2-azobisisobutyronitrile (AIBN) as initiator in ethanol. A layer of polydopamine (PDA) is firstly deposited onto PP surface, which not only offers good interfacial adhesion with PP, but also supplies secondary reaction sites (-NH{sub 2}) to covalently anchor thiol groups onto PP surface. Then the radical chain transfer to surface-bonded thiol groups and surface re-initiated polymerization of MPC lead to the formation of a thin layer of polymer brush (PMPC) with cell outer membrane mimetic structure on PP surface. X-ray photoelectron spectrophotometer (XPS), atomic force microscopy (AFM) and water contact angle measurements are used to characterize the PP surfaces before and after modification. The protein adsorption and platelet adhesion experiments are also employed to evaluate the interactions of PP surface with biomolecules. The results show that PMPC is successfully grafted onto PP surface. In comparison with bare PP, the resultant PP-PMPC surface exhibits greatly improved protein and platelet resistance performance, which is the contribution of both increased surface hydrophilicity and zwitterionic structure. More importantly, the residue thiol groups on PP-PMPC surface create a new pathway to further functionalize such

  2. Enhancing mHealth Technology in the PCMH Environment to Activate Chronic Care Patients

    Science.gov (United States)

    2017-09-01

    Award Number: W81XWH-15-C-0070 TITLE: Enhancing mHealth Technology in the PCMH Environment to Activate Chronic Care Patients PRINCIPAL...Enhancing mHealth Technology in the PCMH Environment to Activate Chronic Care Patients 5a. CONTRACT NUMBER W81XWH-15-C-0070 5b. GRANT NUMBER 5c...Continuing Education Meeting - Poster #2 – presented 11/29/16, National Harbor, Maryland – “Enhancing mHealth Technology in the DoD’s PCMH Environment to

  3. Wide-field surface-enhanced CARS microscopy of cells (Conference Presentation)

    Science.gov (United States)

    Fast, Alexander; Kenison, John T.; Potma, Eric O.

    2017-02-01

    We have previously demonstrated a total internal reflection, wide-field CARS microscope, where the signal is enhanced with the aid of a thin gold layer that supports surface plasmon polariton resonances. This surface-enhanced CARS microscope is capable of generating images of lipid structures in close proximity (visualizing lipids in aqueous media, including imaging of cells, with a unique surface-sensitive contrast that cannot be obtained with conventional CARS microscopy.

  4. Climate regulation enhances the value of second generation biofuel technology

    Science.gov (United States)

    Hertel, T. W.; Steinbuks, J.; Tyner, W.

    2014-12-01

    Commercial scale implementation of second generation (2G) biofuels has long been 'just over the horizon - perhaps a decade away'. However, with recent innovations, and higher oil prices, we appear to be on the verge of finally seeing commercial scale implementations of cellulosic to liquid fuel conversion technologies. Interest in this technology derives from many quarters. Environmentalists see this as a way of reducing our carbon footprint, however, absent a global market for carbon emissions, private firms will not factor this into their investment decisions. Those interested in poverty and nutrition see this as a channel for lessening the biofuels' impact on food prices. But what is 2G technology worth to society? How valuable are prospective improvements in this technology? And how are these valuations affected by future uncertainties, including climate regulation, climate change impacts, and energy prices? This paper addresses all of these questions. We employ FABLE, a dynamic optimization model for the world's land resources which characterizes the optimal long run path for protected natural lands, managed forests, crop and livestock land use, energy extraction and biofuels over the period 2005-2105. By running this model twice for each future state of the world - once with 2G biofuels technology available and once without - we measure the contribution of the technology to global welfare. Given the uncertainty in how these technologies are likely to evolve, we consider a range cost estimates - from optimistic to pessimistic. In addition to technological uncertainty, there is great uncertainty in the conditions characterizing our baseline for the 21st century. For each of the 2G technology scenarios, we therefore also consider a range of outcomes for key drivers of global land use, including: population, income, oil prices, climate change impacts and climate regulation. We find that the social valuation of 2G technologies depends critically on climate change

  5. Technology-Enhanced Problem-Based Learning Methodology in Geographically Dispersed Learners of Tshwane University of Technology

    Directory of Open Access Journals (Sweden)

    Sibitse M. Tlhapane

    2010-03-01

    Full Text Available Improving teaching and learning methodologies is not just a wish but rather strife for most educational institutions globally. To attain this, the Adelaide Tambo School of Nursing Science implemented a Technology-enhanced Problem-Based Learning methodology in the programme B Tech Occupational Nursing, in 2006. This is a two-year post-basic nursing program. The students are geographically dispersed and the curriculum design is the typically student-centred outcomes-based education. The research question posed by this paper is: How does technology-enhanced problem-based learning enhance student-centred learning, thinking skills, social skills and social space for learners? To answer the above question, a case study with both qualitative and quantitative data was utilised. The participants consisted of all students registered for the subject Occupational Health level 4. The sample group was chosen from willing participants from the Pretoria, eMalahleni and Polokwane learning sites, using the snowball method. This method was seen as appropriate due to the timing of the study. Data was collected using a questionnaire with both open and closed-ended questions. An analyses of the students‟ end of year examination was also done, including a comparison of performances by students on technology enhanced problem-based learning and those on problem-based learning only. The findings revealed that with Technology-enhanced Problem Based Learning (PBL, students‟ critical thinking, problem solving, and social skills improved and that social space was enhanced. This was supported by improved grades in students‟ on Technology-enhanced PBL as compared to those on PBL only.

  6. Surface-Enhanced Raman Scattering (SERS) for Detection in Immunoassays. Applications, fundamentals, and optimization

    Energy Technology Data Exchange (ETDEWEB)

    Driskell, Jeremy Daniel [Iowa State Univ., Ames, IA (United States)

    2006-08-09

    Immunoassays have been utilized for the detection of biological analytes for several decades. Many formats and detection strategies have been explored, each having unique advantages and disadvantages. More recently, surface-enhanced Raman scattering (SERS) has been introduced as a readout method for immunoassays, and has shown great potential to meet many key analytical figures of merit. This technology is in its infancy and this dissertation explores the diversity of this method as well as the mechanism responsible for surface enhancement. Approaches to reduce assay times are also investigated. Implementing the knowledge gained from these studies will lead to a more sensitive immunoassay requiring less time than its predecessors. This dissertation is organized into six sections. The first section includes a literature review of the previous work that led to this dissertation. A general overview of the different approaches to immunoassays is given, outlining the strengths and weaknesses of each. Included is a detailed review of binding kinetics, which is central for decreasing assay times. Next, the theoretical underpinnings of SERS is reviewed at its current level of understanding. Past work has argued that surface plasmon resonance (SPR) of the enhancing substrate influences the SERS signal; therefore, the SPR of the extrinsic Raman labels (ERLs) utilized in our SERS-based immunoassay is discussed. Four original research chapters follow the Introduction, each presented as separate manuscripts. Chapter 2 modifies a SERS-based immunoassay previously developed in our group, extending it to the low-level detection of viral pathogens and demonstrating its versatility in terms of analyte type, Chapter 3 investigates the influence of ERL size, material composition, and separation distance between the ERLs and capture substrate on the SERS signal. This chapter links SPR with SERS enhancement factors and is consistent with many of the results from theoretical treatments

  7. Enhancing public involvement in assistive technology design research.

    Science.gov (United States)

    Williamson, Tracey; Kenney, Laurence; Barker, Anthony T; Cooper, Glen; Good, Tim; Healey, Jamie; Heller, Ben; Howard, David; Matthews, Martin; Prenton, Sarah; Ryan, Julia; Smith, Christine

    2015-05-01

    To appraise the application of accepted good practice guidance on public involvement in assistive technology research and to identify its impact on the research team, the public, device and trial design. Critical reflection and within-project evaluation were undertaken in a case study of the development of a functional electrical stimulation device. Individual and group interviews were undertaken with lay members of a 10 strong study user advisory group and also research team members. Public involvement was seen positively by research team members, who reported a positive impact on device and study designs. The public identified positive impact on confidence, skills, self-esteem, enjoyment, contribution to improving the care of others and opportunities for further involvement in research. A negative impact concerned the challenge of engaging the public in dissemination after the study end. The public were able to impact significantly on the design of an assistive technology device which was made more fit for purpose. Research team attitudes to public involvement were more positive after having witnessed its potential first hand. Within-project evaluation underpins this case study which presents a much needed detailed account of public involvement in assistive technology design research to add to the existing weak evidence base. The evidence base for impact of public involvement in rehabilitation technology design is in need of development. Public involvement in co-design of rehabilitation devices can lead to technologies that are fit for purpose. Rehabilitation researchers need to consider the merits of active public involvement in research.

  8. Investigation of Surface Preparations to Enhance Photon Doppler Velocimetry Measurements

    Science.gov (United States)

    2015-08-01

    of Angle, Surface Profilometery, and Optical Photography at 10-, 20-, and 40-Times Magnifications 53 Appendix J. Kevlar Reflected Power...those recognized by Christian Doppler in 1842.3 Recently, academics studying within the field of shock physics recognized that the invent of fiber ...1.55-μm light that was generated from an IPG ytterbium fiber laser (model ELR- 2-1550-LP-SF). The light was projected to the surfaces through open

  9. Aspects regarding the surface roughness on a steel part cutted using AWJ technology

    Directory of Open Access Journals (Sweden)

    Basarman Adrian-Paul

    2017-01-01

    Full Text Available The abrasive water jet cutting technology is a new and modern technology which uses an abrasive material carried by water at high pressure to pierce and cut a desired material. It is a technology used to cut a high variety of materials, from rocks to glass, metal or even human tissue. Regarding the metal cutting using AWJ technology, the surface roughness is a very important aspect when it comes to surface quality and precision. This paper presents a series of aspects regarding the surface roughness on a C45 steel part cutted using AWJ technology, presenting the variation of the surface roughness and the aspect resulted after cutting, on the surface of the cut.

  10. Understanding and enhancing user acceptance of computer technology

    Science.gov (United States)

    Rouse, William B.; Morris, Nancy M.

    1986-01-01

    Technology-driven efforts to implement computer technology often encounter problems due to lack of acceptance or begrudging acceptance of the personnel involved. It is argued that individuals' acceptance of automation, in terms of either computerization or computer aiding, is heavily influenced by their perceptions of the impact of the automation on their discretion in performing their jobs. It is suggested that desired levels of discretion reflect needs to feel in control and achieve self-satisfaction in task performance, as well as perceptions of inadequacies of computer technology. Discussion of these factors leads to a structured set of considerations for performing front-end analysis, deciding what to automate, and implementing the resulting changes.

  11. Application of polymer flooding technology for enhanced oil recovery

    Directory of Open Access Journals (Sweden)

    Sarkyt Kudaivergenov

    2015-12-01

    Full Text Available Application of brine-initiated gelation of gellan for conformance control and water shutoff operations in field conditions was demonstrated. The developed technology was tested in Kumkol oilfield (Kyzylorda region, Kazakhstan on five injection wells. According to the results of the first oilfield test, the amount of additionally recovered oil during 11 months (from October 1, 2013 till September 1, 2014 was equal to 5890 tons. In 2014, the JSC “NIPIneftegas” (Aktau city, Kazakhstan carried out the second pilot test of polymer flooding technology on the same oilfield. The amount of additionally recovered oil during eight months (from October 2014 till May 2015 was equal to 8695 tons. The technology was tested for water shut-off purposes in producing well of Karabulak oilfield. After one-month treatment of production well the amount of water decreased 16 times in comparison with previous results.

  12. Investigation on the micromilled surface characterization through replica technology

    DEFF Research Database (Denmark)

    Baruffi, Federico; Parenti, P.; Cacciatore, F.

    2016-01-01

    with quality control and tolerances to meet the parts functionality. However, in many cases, the reduced accessibility caused by the part complex features (e.g. microcavities, micro-holes, deep-cores) prevents from performing a direct measurement of the surface, using both contactand non-contact techniques...... for the indirect measurement of micromilled surfaces, characterized by submicrometer roughness levels. The study assesses the performance of the replication method by measuring the surface roughness (in terms of Sa) of specifically designed micromilled flat surfaces. A 3D confocal optical microscope is employed...

  13. Aspects to Be Considered when Implementing Technology-Enhanced Learning Approaches: A Literature Review

    Directory of Open Access Journals (Sweden)

    Patrick Schweighofer

    2015-02-01

    Full Text Available The significance of approaches to technology-enhanced learning (TEL has increased rapidly during the last few years. Nowadays in education different approaches such as game-based learning, web-based learning, video-based online courses, and many others are used on a daily basis. However, what defines the success of technology-enhanced learning approaches and how can such approaches be developed in a structured way? Furthermore, what different aspects have to be considered while doing so? To answer these questions, 4567 publications were analyzed in this present literature review in order to recognize the different aspects of implementing technology-enhanced learning approaches. Finally, 20 categories are defined in four main areas that summarize all the aspects in the field of technology-enhanced learning. Moreover, the study also reveals research areas that are important but hardly investigated in the observed journals of this study.

  14. Proceedings of the First European Workshop on Latent Semantic Analysis in Technology Enhanced Learning

    NARCIS (Netherlands)

    Wild, Fridolin; Kalz, Marco; Van Bruggen, Jan; Koper, Rob

    2007-01-01

    Wild, F., Kalz, M., Van Bruggen, J., & Koper, R. (Eds.) (2007). Proceedings of the First European Workshop on Latent Semantic Analysis in Technology Enhanced Learning. Heerlen, the Netherlands:Open University of the Netherlands.

  15. Technology-enhanced storytelling stimulating parent-child interaction and preschool children's vocabulary knowledge

    NARCIS (Netherlands)

    Teepe, R.C.; Molenaar, I.; Verhoeven, L.T.W.

    2017-01-01

    Preschool children's vocabulary mainly develops verbal through interaction. Therefore, the technology-enhanced storytelling (TES) activity Jeffy's Journey is developed to support parent-child interaction and vocabulary in preschool children. TES entails shared verbal storytelling supported by a

  16. Technology-enhanced storytelling stimulating parent–child interaction and preschool children's vocabulary knowledge

    NARCIS (Netherlands)

    Teepe, R.C.; Molenaar, I.; Verhoeven, L.

    2016-01-01

    Preschool children's vocabulary mainly develops verbal through interaction. Therefore, the technology-enhanced storytelling (TES) activity Jeffy's Journey is developed to support parent–child interaction and vocabulary in preschool children. TES entails shared verbal storytelling supported by a

  17. Biomimetic surface modification of polypropylene by surface chain transfer reaction based on mussel-inspired adhesion technology and thiol chemistry

    Science.gov (United States)

    Niu, Zhijun; Zhao, Yang; Sun, Wei; Shi, Suqing; Gong, Yongkuan

    2016-11-01

    Biomimetic surface modification of polypropylene (PP) is conducted by surface chain transfer reaction based on the mussel-inspired versatile adhesion technology and thiol chemistry, using 2-methacryloyloxyethylphosphorylcholine (MPC) as a hydrophilic monomer mimicking the cell outer membrane structure and 2,2-azobisisobutyronitrile (AIBN) as initiator in ethanol. A layer of polydopamine (PDA) is firstly deposited onto PP surface, which not only offers good interfacial adhesion with PP, but also supplies secondary reaction sites (-NH2) to covalently anchor thiol groups onto PP surface. Then the radical chain transfer to surface-bonded thiol groups and surface re-initiated polymerization of MPC lead to the formation of a thin layer of polymer brush (PMPC) with cell outer membrane mimetic structure on PP surface. X-ray photoelectron spectrophotometer (XPS), atomic force microscopy (AFM) and water contact angle measurements are used to characterize the PP surfaces before and after modification. The protein adsorption and platelet adhesion experiments are also employed to evaluate the interactions of PP surface with biomolecules. The results show that PMPC is successfully grafted onto PP surface. In comparison with bare PP, the resultant PP-PMPC surface exhibits greatly improved protein and platelet resistance performance, which is the contribution of both increased surface hydrophilicity and zwitterionic structure. More importantly, the residue thiol groups on PP-PMPC surface create a new pathway to further functionalize such zwitterion modified PP surface.

  18. Universal Design for Learning: Application for Technology-Enhanced Learning

    Science.gov (United States)

    Morra, Thom; Reynolds, Jim

    2010-01-01

    The construct of Universal Design (UD) has been used in a number of fields such as engineering and architecture to design and produce products and services that are usable by people with a wide variety of characteristics. The field of UD supports a framework that can also be used to enhance the field of education. A number of constructs have been…

  19. Enhancing Field Research Methods with Mobile Survey Technology

    Science.gov (United States)

    Glass, Michael R.

    2015-01-01

    This paper assesses the experience of undergraduate students using mobile devices and a commercial application, iSurvey, to conduct a neighborhood survey. Mobile devices offer benefits for enhancing student learning and engagement. This field exercise created the opportunity for classroom discussions on the practicalities of urban research, the…

  20. Technology-Enhanced EFL Syllabus Design and Materials Development

    Science.gov (United States)

    Nguyen, Long V.

    2008-01-01

    In this paper, I am going to look at the issues of TESOL from one major critical point of view: How the use of the Internet technology might influence TESOL syllabus design and materials development. The article attempts to investigate some possibilities and opportunities provided by the Internet, focusing on the World Wide Web (WWW) as credible…

  1. The Effectiveness of a Technology-Enhanced Flipped Science Classroom

    Science.gov (United States)

    Sezer, Baris

    2017-01-01

    This study examined the effect on the learning and motivation of students of a flipped classroom environment enriched with technology. A mixed research design using a pretest or posttest experimental model, combined with qualitative data, was conducted in a public middle school in Turkey for 2 weeks (three class hours) within a science course.…

  2. Edutainment: Using Technology to Enhance the Management Learner Experience

    Science.gov (United States)

    Makarius, Erin E.

    2017-01-01

    Edutainment, while seemingly a new and trending idea, is quite simply the combination of education and entertainment, or improving learning by making it more engaging. What began as a way to teach children concepts in a fun way (e.g., School House Rock) has evolved into an integration of technology, design, and academics (e.g., TED talks).…

  3. Enhancing Health and Social Care Placement Learning through Mobile Technology

    Science.gov (United States)

    Lea, Susan; Callaghan, Lynne

    2011-01-01

    Health and social care students spend up to 50% of their course in practice. Placements are distributed across a wide geographical area and have varying degrees of IT access and support. Consequently, students may feel isolated from peers, academic staff, and resources required for effective learning. Mobile technology has considerable potential…

  4. Enhancement of Teaching-Learning Process through Multimedia Technology

    Science.gov (United States)

    Charles, R.

    2011-01-01

    The Indian educational system has to meet the challenges of knowledge explosion and its requirement of increased enrolment in higher education. Computer and technology plays a pre-dominant role to meet out its challenges. Recent innovative Educational approach recommends self and sensory oriented instruction. Computer based multimedia is a tool…

  5. Removal of arsenic by enhanced coagulation and membrane technology

    Energy Technology Data Exchange (ETDEWEB)

    Chang, S.D.; Ruiz, H. [CH2M Hill, Santa Ana, CA (United States); Bellamy, W.D. [CH2M Hill, Englewood, CO (United States); Spangenberg, C.W.; Clark, D.L. [Irvine Ranch Water District, Irvine, CA (United States)

    1994-12-31

    The US EPA is promulgating a new MCL for arsenic based on epidemiology studies. The concern from the water industry is that the new MCL will be significantly lower than the current MCL of 50 {micro}g/L. The new MCL, some speculate may be as low as 2 {micro}g/L or less, is expected to have a significant impact on water utilities that depend on groundwater supply or use aquifer storage and recovery technology for potable water resources. A questionnaire sent to the participants at the Arsenic Workshop (May, 1993) sponsored by Association of California Water Agencies and the Metropolitan Water District of Southern California indicated that 66% of the 50 water agencies responded will not be in compliance if the new MCL is set at 5 AGIL. The issues concern most of the water utilities are compliance cost and treatment technologies. There are very few, if any, water utilities that are treating water with the objective of removing arsenic to levels less than 2 {micro}g/L. Some technologies such as reverse osmosis are capable of removing arsenic to a very low level, however, there is no data available due to the analytical limitation. All these information are critical to the development of treatment technologies and compliance cost.

  6. Enhancing knowledge sharing management using BIM technology in construction.

    Science.gov (United States)

    Ho, Shih-Ping; Tserng, Hui-Ping; Jan, Shu-Hui

    2013-01-01

    Construction knowledge can be communicated and reused among project managers and jobsite engineers to alleviate problems on a construction jobsite and reduce the time and cost of solving problems related to constructability. This paper proposes a new methodology for the sharing of construction knowledge by using Building Information Modeling (BIM) technology. The main characteristics of BIM include illustrating 3D CAD-based presentations and keeping information in a digital format and facilitation of easy updating and transfer of information in the BIM environment. Using the BIM technology, project managers and engineers can gain knowledge related to BIM and obtain feedback provided by jobsite engineers for future reference. This study addresses the application of knowledge sharing management using BIM technology and proposes a BIM-based Knowledge Sharing Management (BIMKSM) system for project managers and engineers. The BIMKSM system is then applied in a selected case study of a construction project in Taiwan to demonstrate the effectiveness of sharing knowledge in the BIM environment. The results demonstrate that the BIMKSM system can be used as a visual BIM-based knowledge sharing management platform by utilizing the BIM technology.

  7. The role of information technology in enhancing the administrative ...

    African Journals Online (AJOL)

    The major objective of this paper is to demonstrate that the administrative capacity of a public organisation is a function of both high-level human resource capacity and the effective utilisation of Information Technology. In order to substantiate this, the paper elicited data from civil service employees in Ethiopia and USA, ...

  8. Treatability of South African surface waters by enhanced coagulation

    African Journals Online (AJOL)

    2013-06-05

    Jun 5, 2013 ... standard, many South African water treatment managers may need to consider adoption of enhanced coagulation (EC) in the near future to achieve both turbidity and NOM removal. From the study of 4 South African inland waters, this paper demonstrates that UV254 absorbance provides a more accessible ...

  9. Parametric Surfaces Competition: Using Technology to Foster Creativity

    Science.gov (United States)

    Kaur, Manmohan; Wangler, Thomas

    2014-01-01

    Although most calculus students are comfortable with the Cartesian equations of curves and surfaces, they struggle with the concept of parameters. A multivariable calculus course is really the time to nail this concept down, once and for all, since it provides an easy way to represent many beautiful and useful surfaces, and graph them using a…

  10. Pipette-surface interaction: current enhancement and intrinsic force.

    Science.gov (United States)

    Clarke, Richard W; Zhukov, Alexander; Richards, Owen; Johnson, Nicholas; Ostanin, Victor; Klenerman, David

    2013-01-09

    There is an intrinsic repulsion between glass and cell surfaces that allows noninvasive scanning ion conductance microscopy (SICM) of cells and which must be overcome in order to form the gigaseals used for patch clamping investigations of ion channels. However, the interactions of surfaces in physiological solutions of electrolytes, including the presence of this repulsion, for example, do not obviously agree with the standard Derjaguin-Landau-Verwey-Overbeek (DLVO) colloid theory accurate at much lower salt concentrations. In this paper we investigate the interactions of glass nanopipettes in this high-salt regime with a variety of surfaces and propose a way to resolve DLVO theory with the results. We demonstrate the utility of this understanding to SICM by topographically mapping a live cell's cytoskeleton. We also report an interesting effect whereby the ion current though a nanopipette can increase under certain conditions upon approaching an insulating surface, rather than decreasing as would be expected. We propose that this is due to electroosmotic flow separation, a high-salt electrokinetic effect. Overall these experiments yield key insights into the fundamental interactions that take place between surfaces in strong solutions of electrolytes.

  11. The Innovative Directions In Development And Implementations Of Hybrid Technologies In Surface Engineering

    Directory of Open Access Journals (Sweden)

    Mazurkiewicz A.

    2015-09-01

    Full Text Available The dynamics of the development of modern technology depends, to a great extent, on the possibilities of producing the innovative materials with high functionality parameters, which could be used in modern, highly advanced technological processes. Surface engineering plays a very important role in this area. This is mainly due to the fact that, for many structural materials, the possibilities of classical formation of their properties (e.g., by heat treatment or the selection of the microstructure, chemical and phase composition have been practically used up. The material and technological achievements in the surface engineering area allow the modification of the properties of the surface layer of tool and machine components. As a result, they may be better suited to work in increasingly difficult and more demanding conditions. The hybrid technologies, combining several different methods of surface treatment in one complex technological process, are the most advanced solutions compared to already known surface engineering methods. In the article, the authors present the possibilities of shaping the functional properties of the surface layer. The authors describe problems associated with the development of the hybrid technology and provide the examples of physical modelling, design, technological development, and the practical application of a hybrid technology. In this work, the authors also identify the areas whose development is needed for more effective transfer of surface engineering innovations to business applications.

  12. Resonant-enhanced full-color emission of quantum-dot-based micro LED display technology.

    Science.gov (United States)

    Han, Hau-Vei; Lin, Huang-Yu; Lin, Chien-Chung; Chong, Wing-Cheung; Li, Jie-Ru; Chen, Kuo-Ju; Yu, Peichen; Chen, Teng-Ming; Chen, Huang-Ming; Lau, Kei-May; Kuo, Hao-Chung

    2015-12-14

    Colloidal quantum dots which can emit red, green, and blue colors are incorporated with a micro-LED array to demonstrate a feasible choice for future display technology. The pitch of the micro-LED array is 40 μm, which is sufficient for high-resolution screen applications. The method that was used to spray the quantum dots in such tight space is called Aerosol Jet technology which uses atomizer and gas flow control to obtain uniform and controlled narrow spots. The ultra-violet LEDs are used in the array to excite the red, green and blue quantum dots on the top surface. To increase the utilization of the UV photons, a layer of distributed Bragg reflector was laid down on the device to reflect most of the leaked UV photons back to the quantum dot layers. With this mechanism, the enhanced luminous flux is 194% (blue), 173% (green) and 183% (red) more than that of the samples without the reflector. The luminous efficacy of radiation (LER) was measured under various currents and a value of 165 lm/Watt was recorded.

  13. Enhancing biodegradation and energy generation via roughened surface graphite electrode in microbial desalination cell.

    Science.gov (United States)

    Ebrahimi, Atieh; Yousefi Kebria, Daryoush; Najafpour Darzi, Ghasem

    2017-09-01

    The microbial desalination cell (MDC) is known as a newly developed technology for water and wastewater treatment. In this study, desalination rate, organic matter removal and energy production in the reactors with and without desalination function were compared. Herein, a new design of plain graphite called roughened surface graphite (RSG) was used as the anode electrode in both microbial fuel cell (MFC) and MDC reactors for the first time. Among the three type of anode electrodes investigated in this study, RSG electrode produced the highest power density and salt removal rate of 10.81 W/m3 and 77.6%, respectively. Such a power density was 2.33 times higher than the MFC reactor due to the junction potential effect. In addition, adding the desalination function to the MFC reactor enhanced columbic efficiency from 21.8 to 31.4%. These results provided a proof-of-concept that the use of MDC instead of MFC would improve wastewater treatment efficiency and power generation, with an added benefit of water desalination. Furthermore, RSG can successfully be employed in an MDC or MFC, enhancing the bio-electricity generation and salt removal.

  14. Cross-Polarized Surface-Enhanced Infrared Spectroscopy by Fano-Resonant Asymmetric Metamaterials.

    Science.gov (United States)

    Ishikawa, Atsushi; Hara, Shuhei; Tanaka, Takuo; Hayashi, Yasuhiko; Tsuruta, Kenji

    2017-06-09

    Plasmonic metamaterials have overcome fundamental limitations in conventional optics by their capability to engineer material resonances and dispersions at will, holding great promise for sensing applications. Recent demonstrations of metamaterial sensors, however, have mainly relied on their resonant nature for strong optical interactions with molecules, but few examples fully exploit their functionality to manipulate the polarization of light. Here, we present cross-polarized surface-enhanced infrared absorption (SEIRA) by the Fano-resonant asymmetric metamaterial allowing for strong background suppression as well as significant field enhancement. The metamaterial is designed to exhibit the controlled Fano resonance with the cross-polarization conversion property at 1730 cm-1, which spectrally overlaps with the C=O vibrational mode. In the cross-polarized SEIRA measurement, the C=O mode of poly(methyl methacrylate) molecules is clearly observed as a distinct dip within a Fano-resonant transmission peak of the metamaterial. The vibrational signal contrast is then improved based on the cross-polarized detection scheme where only the light interacting with the metamaterial-molecular coupled system is detected by totally eliminating the unwanted background light. Our metamaterial approach achieves the zeptomole sensitivity with a large signal-to-noise ratio in the far-field measurement, paving the way toward the realization of ultrasensitive IR inspection technologies.

  15. Surface properties of sulphur based surface modified n-Cu2O thin films for enhanced liquefied petroleum gas sensing

    Science.gov (United States)

    Bandara, K. N. D.; Jayathilaka, K. M. D. C.; Gunewardene, M. S.; Dissanayake, D. P.; Jayanetti, J. K. D. S.

    2017-12-01

    The surface of electrodeposited n-Cu2O thin films were modified by sulphidation using aqueous Na2S followed by (NH4)2S vapor treatment. Compared to untreated thin films, the resultant films showed an enhanced response to liquefied petroleum (LP) gas at a relatively low operating temperature (~45 °C), one of the lowest reported for a cuprous oxide based material. X-ray diffraction spectra confirmed that the films were of single phase. Observed by contact angle measurements and energy dispersive x-ray spectroscopy, (NH4)2S vapor treatment converted the highly wetting sulphided films containing both Na and S to a partially wetting surface by forming sulphur on the film surface. This modification on the film surface, enabled the sensor response to recover to an ambient level after stoppage of LP gas flow, which sulphidation alone was inapt. Scanning electron micrographs complemented roughness measurements made by atomic force microscopy and showed a transformation of polycrystalline morphology of bare n-Cu2O film to one having highly porous structures, which thereby increased the surface area of the surface modified films. Therefore, this work demonstrates that the surface of the n-type Cu2O thin films modified by (NH4)2S vapor treatment and sulphidation can alter the surface wetting nature and increase the surface area to enhance LP gas sensing at a relatively low temperature.

  16. Biomolecular modification of zirconia surfaces for enhanced biocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Shih-Kuang; Hsu, Hsueh-Chuan [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan, ROC (China); Ho, Wen-Fu [Department of Chemical and Materials Engineering, National University of Kaohsiung, Taiwan, ROC (China); Yao, Chun-Hsu [Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung 40402, Taiwan, ROC (China); Chang, Pai-Ling [Taoyuan General Hospital, Taoyuan 33004, Taiwan, ROC (China); Wu, Shih-Ching, E-mail: scwu@ctust.edu.tw [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan, ROC (China)

    2014-12-01

    Yttria-tetragonal zirconia polycrystal (Y-TZP) is a preferred biomaterial due to its good mechanical properties. In order to improve the biocompatibility of zirconia, RGD-peptide derived from extracellular matrix proteins was employed to modify the surface of Y-TZP to promote cell adhesion in this study. The surface of Y-TZP specimens was first modified using a hydrothermal method for different lengths of time. The topographies of modified Y-TZP specimens were analyzed by contact angle, XRD, FTIR, AFM, and FE-SEM. The mechanical properties were evaluated using Vickers hardness and three point bending strength. Then, the RGD-peptide was immobilized on the surface of the Y-TZP by chemical treatment. These RGD-peptide immobilized Y-TZP specimens were characterized by FTIR and AFM, and then were cocultured with MG-63 osteoblast cells for biocompatibility assay. The cell morphology and proliferation were evaluated by SEM, WST-1, and ALP activity assay. The XRD results indicated that the phase transition, from tetragonal phase to monoclinic phase, was increased with a longer incubation time of hydrothermal treatment. However, there were no significant differences in mechanical strengths after RGD-peptide was successfully grafted onto the Y-TZP surface. The SEM images showed that the MG-63 cells appeared polygonal, spindle-shaped, and attached on the RGD-peptide immobilized Y-TZP. The proliferation and cellular activities of MG-63 cells on the RGD-peptide immobilized Y-TZP were better than that on the unmodified Y-TZP. From the above results, the RGD-peptide can be successfully grafted onto the hydrothermal modified Y-TZP surface. The RGD-peptide immobilized Y-TZP can increase cell adhesion, and thus, improve the biocompatibility of Y-TZP. - Highlights: • Covalent bonding between peptide and Y-TZP was proposed. • Stable biomimetic structures produced on the surface of zirconia. • The biocompatibility was improved.

  17. Dynamic placement of plasmonic hotspots for super-resolution surface-enhanced Raman scattering.

    Science.gov (United States)

    Ertsgaard, Christopher T; McKoskey, Rachel M; Rich, Isabel S; Lindquist, Nathan C

    2014-10-28

    In this paper, we demonstrate dynamic placement of locally enhanced plasmonic fields using holographic laser illumination of a silver nanohole array. To visualize these focused "hotspots", the silver surface was coated with various biological samples for surface-enhanced Raman spectroscopy (SERS) imaging. Due to the large field enhancements, blinking behavior of the SERS hotspots was observed and processed using a stochastic optical reconstruction microscopy algorithm enabling super-resolution localization of the hotspots to within 10 nm. These hotspots were then shifted across the surface in subwavelength (super-resolution chemical imaging.

  18. Technology-enhanced focus groups as a component of instrument development.

    Science.gov (United States)

    Strout, Tania D; DiFazio, Rachel L; Vessey, Judith A

    2017-06-22

    Background Bullying is a critical public health problem and a screening tool for use in healthcare is needed. Focus groups are a common tool for generating qualitative data when developing an instrument and evidence suggests that technology-enhanced focus groups can be effective in simultaneously engaging participants from diverse settings. Aim To examine the use of technology-enhanced focus groups in generating an item pool to develop a youth-bullying screening tool. Discussion The authors explore methodological and ethical issues related to conducting technology-enhanced focus groups, drawing on their experience in developing a youth-bullying measure. They conducted qualitative focus groups with professionals from the front lines of bullying response and intervention. They describe the experience of conducting technology-enhanced focus group sessions, focusing on the methodological and ethical issues that researchers engaging in similar work may encounter. Challenges associated with this methodology include establishing rapport among participants, privacy concerns and limited non-verbal communication. Conclusion The use of technology-enhanced focus groups can be valuable in obtaining rich data from a wide variety of disciplines and contexts. Organising these focus groups was inexpensive and preferred by the study's participants. Implications for practice Researchers should consider using technology-enhanced focus groups to generate data to develop health-related measurement tools.

  19. Enhanced extraction efficiency of fluorescent SiC by surface nanostructuring

    DEFF Research Database (Denmark)

    Ou, Yiyu; Jokubavicius, Valdas; Yakimova, Rositza

    2012-01-01

    Antireflective structures were fabricated on fluorescent 6H-SiC for white LEDs to enhance the extraction efficiency. Average surface reflectance decreased from 22.1% to 5.1% over a broad range, and luminescence intensity was enhanced by 41%.......Antireflective structures were fabricated on fluorescent 6H-SiC for white LEDs to enhance the extraction efficiency. Average surface reflectance decreased from 22.1% to 5.1% over a broad range, and luminescence intensity was enhanced by 41%....

  20. Enhancing the interaction strength and capacities of hydrogen storage via surface adsorption

    Science.gov (United States)

    Brown, Craig

    2008-03-01

    Storing Hydrogen molecules in porous media based on a physisorption mechanism is one possible approach to reach the US Department of Energy targets for on-board hydrogen storage. Although the storage capacities of metal-organic frameworks (MOFs) have progressed significantly over recent years, some technological obstacles pose challenges for their future improvement. These include the generally low H2 adsorption enthalpy limiting room temperature applications and the lack of understanding of surface packing density hindering the efficient improvement of H2 adsorption uptake. To improve the H2 affinity in MOFs, our previous work has shown that the coordinatively unsaturated metal centers (CUMCs) can greatly enhance the H2 binding strength. Our current study of MOF-74 will be presented, showing that its open Zn^2+ ions bind H2 strongly and are identified as being responsible for the large initial H2 adsorption enthalpy of 8.4 kJ/mol. In all, there are four H2 adsorption sites in MOF-74 identified by neutron powder diffraction. These four hydrogen adsorption sites are closely packed in MOF-74 and form a one dimensional nanoscale tube structure. We also demonstrate an interesting correlation that MOFs with CUMCs generally show larger surface packing densities than that of other MOFs without CUMCs. The implications of this will be addressed.

  1. Enhanced/Synthetic Vision and Head-Worn Display Technologies for Terminal Maneuvering Area NextGen Operations

    Science.gov (United States)

    Arthur, Jarvis J., III; Prinzell, Lawrence J.; Williams, Steven P.; Bailey, Randall E.; Shelton, Kevin J.; Norman, R. Mike

    2011-01-01

    NASA is researching innovative technologies for the Next Generation Air Transportation System (NextGen) to provide a "Better-Than-Visual" (BTV) capability as adjunct to "Equivalent Visual Operations" (EVO); that is, airport throughputs equivalent to that normally achieved during Visual Flight Rules (VFR) operations rates with equivalent and better safety in all weather and visibility conditions including Instrument Meteorological Conditions (IMC). These new technologies build on proven flight deck systems and leverage synthetic and enhanced vision systems. Two piloted simulation studies were conducted to access the use of a Head-Worn Display (HWD) with head tracking for synthetic and enhanced vision systems concepts. The first experiment evaluated the use a HWD for equivalent visual operations to San Francisco International Airport (airport identifier: KSFO) compared to a visual concept and a head-down display concept. A second experiment evaluated symbology variations under different visibility conditions using a HWD during taxi operations at Chicago O'Hare airport (airport identifier: KORD). Two experiments were conducted, one in a simulated San Francisco airport (KSFO) approach operation and the other, in simulated Chicago O'Hare surface operations, evaluating enhanced/synthetic vision and head-worn display technologies for NextGen operations. While flying a closely-spaced parallel approach to KSFO, pilots rated the HWD, under low-visibility conditions, equivalent to the out-the-window condition, under unlimited visibility, in terms of situational awareness (SA) and mental workload compared to a head-down enhanced vision system. There were no differences between the 3 display concepts in terms of traffic spacing and distance and the pilot decision-making to land or go-around. For the KORD experiment, the visibility condition was not a factor in pilot's rating of clutter effects from symbology. Several concepts for enhanced implementations of an unlimited field

  2. Plasma technologies application for building materials surface modification

    Science.gov (United States)

    Volokitin, G. G.; Skripnikova, N. K.; Volokitin, O. G.; Shehovtzov, V. V.; Luchkin, A. G.; Kashapov, N. F.

    2016-01-01

    Low temperature arc plasma was used to process building surface materials, such as silicate brick, sand lime brick, concrete and wood. It was shown that building surface materials modification with low temperature plasma positively affects frost resistance, water permeability and chemical resistance with high adhesion strength. Short time plasma processing is rather economical than traditional processing thermic methods. Plasma processing makes wood surface uniquely waterproof and gives high operational properties, dimensional and geometrical stability. It also increases compression resistance and decreases inner tensions level in material.

  3. Engineering Plasmonic Nanopillar Arrays for Surface-enhanced Raman Spectroscopy

    DEFF Research Database (Denmark)

    Wu, Kaiyu

    deviation of ~14% (660 data points) across a 5 x 5 mm2 surface area. Lastly, a further improved process shows that high-density NPs exhibit unrivalled macroscale SERS uniformities (RSD: ∼2.5% in mm scale, ∼7% in inch scale) and SERS reproducibilities (RSD: ∼1.5% across three wafers), while at the same time...

  4. Treatability of South African surface waters by enhanced coagulation

    African Journals Online (AJOL)

    The majority of South African inland surface water sources are compromised due to a long-standing national policy of mandatory return flows. With renewed emphasis on the removal of organic carbon in the latest SANS 241 water quality standard, many South African water treatment managers may need to consider ...

  5. Design methodology to enhance high impedance surfaces performances

    Directory of Open Access Journals (Sweden)

    M. Grelier

    2014-04-01

    Full Text Available A methodology is introduced for designing wideband, compact and ultra-thin high impedance surfaces (HIS. A parametric study is carried out to examine the effect of the periodicity on the electromagnetic properties of an HIS. This approach allows designers to reach the best trade-off for HIS performances.

  6. Irradiation induced grain growth and surface emission enhancement ...

    Indian Academy of Sciences (India)

    The photoluminescence (PL) study was carried out by band to band excitation ( λ e x = 220 nm) upon ZnS : Mn, which results into two emission peaks corresponding to surface states and Mn+2 emission, respectively. The ion fluence for irradiation experiment so chosen were 1 × 1011, 5 × 1011, 5 × 1012 and 1013 Cl/cm2.

  7. Surface enhanced Raman spectra of the organic nonlinear optic ...

    Indian Academy of Sciences (India)

    Wintec

    sorbed in a flat on orientation to the surface. The SERS spectral studies predict a tilted orientation of ethylenic bridge with respect to the phenyl ring. Keywords. Adsorption behaviour; SERS; methyl 3-(4-methoxy phenyl)prop-2-enoate; silver nanoparti- cles; DFT. 1. Introduction. The elucidation of the adsorption mechanism of ...

  8. Enhancing the chroma of pigmented polymers using antireflective surface structures

    DEFF Research Database (Denmark)

    Clausen, Jeppe Sandvik; Christiansen, Alexander Bruun; Kristensen, Anders

    2013-01-01

    In this paper we investigate how the color of a pigmented polymer is affected by reduction of the reflectance at the air-polymer interface. Both theoretical and experimental investigations show modified diffuse-direct reflectance spectra when the reflectance of the surface is lowered. Specifically...

  9. A reflexive evaluation of technology-enhanced learning

    Directory of Open Access Journals (Sweden)

    Suzanne Young

    2017-11-01

    Full Text Available This article explores the lived experiences of two academics in a UK Higher Education Institution who have embedded digital learning approaches within their curriculum delivery. Achieving student excellence can be impeded by a lack of engagement and sense of identity on large courses. Digital learning strategies can offer opportunities to overcome these challenges by empowering students to engage self-confidently. Through an evaluation of the authors’ own experiences of using social media, polling and web-conferencing software, the article shows how interacting with students via a range of learning technologies can create more inclusive and engaging learning environments. Including feedback from students within this article provides evidence that diversification of communication within teaching and learning practice gives students more choice and opportunity to interact with both their peers and teaching staff. The article concludes with recommendations for embedding technology, whilst acknowledging the well-established value of face-to-face interaction.

  10. Enhancing e-health information systems with agent technology.

    Science.gov (United States)

    Nguyen, Minh Tuan; Fuhrer, Patrik; Pasquier-Rocha, Jacques

    2009-01-01

    Agent Technology is an emerging and promising research area in software technology, which increasingly contributes to the development of value-added information systems for large healthcare organizations. Through the MediMAS prototype, resulting from a case study conducted at a local Swiss hospital, this paper aims at presenting the advantages of reinforcing such a complex E-health man-machine information organization with software agents. The latter will work on behalf of human agents, taking care of routine tasks, and thus increasing the speed, the systematic, and ultimately the reliability of the information exchanges. We further claim that the modeling of the software agent layer can be methodically derived from the actual "classical" laboratory organization and practices, as well as seamlessly integrated with the existing information system.

  11. Enhanced Antifungal Bioactivity of Coptis Rhizome Prepared by Ultrafining Technology

    Directory of Open Access Journals (Sweden)

    Ping-Chung Kuo

    2014-01-01

    Full Text Available The aim of this study was to identify and quantify the bioactive constituents in the methanol extracts of Coptis Rhizome prepared by ultrafining technology. The indicator compound was identified by spectroscopic method and its purity was determined by HPLC. Moreover, the crude extracts and indicator compound were examined for their ability to inhibit the growth of Rhizoctonia solani Kühn AG-4 on potato dextrose agar plates. The indicator compound is a potential candidate as a new plant derived pesticide to control Rhizoctonia damping-off in vegetable seedlings. In addition, the extracts of Coptis Rhizome prepared by ultrafining technology displayed higher contents of indicator compound; they not only improve their bioactivity but also reduce the amount of the pharmaceuticals required and, thereby, decrease the environmental degradation associated with the harvesting of the raw products.

  12. Enhanced E-bed bottoms upgrading using latest catalytic technology

    Energy Technology Data Exchange (ETDEWEB)

    Toshima, H.; Mayo, S.; Sedlacek, Z.; Hughes, T.; De Wind, M. [Albermarle Corp., Amsterdam (Netherlands)

    2009-07-01

    The profitability of refineries depends on heavy oil upgrading in terms of price, conversion, yields and quality of the product. The Ebullated-bed process represents a solution for the effective primary upgrading of heavy oils. Since the 1970s, Albemarle has commercialized several E-bed catalysts to upgrade the bottoms in low sediment and high hydrogenation operations. Although an E-bed is used to maximize the conversion of vacuum residuum (VR), it is often limited by fouling caused by sediment in the product. In order to reduce sedimentation in the product, Albemarle developed an improved E-bed catalytic technology by characterizing the asphaltenes and sediments in order to better understand the oil chemistry and compatibility. The most recent development involves the patented catalyst-staging technology and the improved single catalyst application. Both achieve very low sediment or higher hydrodesulphurization (HDS) and Conradson carbon (CCR) removal for improved bottom upgrading. tabs., figs.

  13. Plasma enhanced C1 chemistry for green technology

    Science.gov (United States)

    Nozaki, Tomohiro

    2013-09-01

    Plasma catalysis is one of the innovative next generation green technologies that meet the needs for energy and materials conservation as well as environmental protection. Non-thermal plasma uniquely generates reactive species independently of reaction temperature, and these species are used to initiate chemical reactions at unexpectedly lower temperatures than normal thermochemical reactions. Non-thermal plasma thus broadens the operation window of existing chemical conversion processes, and ultimately allows modification of the process parameters to minimize energy and material consumption. We have been specifically focusing on dielectric barrier discharge (DBD) as one of the viable non-thermal plasma sources for practical fuel reforming. In the presentation, room temperature one-step conversion of methane to methanol and hydrogen using a miniaturized DBD reactor (microplasma reactor) is highlighted. The practical impact of plasma technology on existing C1-chemistry is introduced, and then unique characteristics of plasma fuel reforming such as non-equilibrium product distribution is discussed.

  14. Supporting technology for enhanced oil recovery - EOR thermal processes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    This report contains the results of efforts under the six tasks of the Eighth Amendment and Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section.

  15. From STEM to STEAM: Strategies for Enhancing Engineering & Technology Education

    OpenAIRE

    Andy M. Connor; Sangeeta Karmokar; Chris Whittington

    2015-01-01

    This paper sets out to challenge the common pedagogies found in STEM (Science, Technology, Engineering and Mathematics) education with a particular focus on engineering. The dominant engineering pedagogy remains “chalk and talk”; despite research evidence that demonstrates its ineffectiveness. Such pedagogical approaches do not embrace the possibilities provided by more student-centric approaches and more active learning. The paper argues that there is a potential confusion in engineering edu...

  16. Materials and Mechanics of Metamaterial Enhanced MEMS for Terahertz Technology

    Science.gov (United States)

    2013-12-23

    for electrical excitation in comparison to magnetic excitation in terms of hybridization arising from inductive and capacitive coupling...the capacitive and inductive coupling. However, for ABC-SRRs, in-plane shifting between the two resonators by more than 0.375 Lo (Lo=SRR sidelength...Field by Radar Cross Section Measurements," Presented at the International Workshop on Optical Terahertz Science and Technology, Santa Barbara, CA

  17. Mars rover rock abrasion tool performance enhanced by ultrasonic technology.

    Science.gov (United States)

    Macartney, A.; Li, X.; Harkness, P.

    2016-12-01

    The Mars exploration Athena science goal is to explore areas where water may have been present on the early surface of Mars, and investigate the palaeo-environmental conditions of these areas in relation to the existence of life. The Rock Abrasion Tool (RAT) designed by Honeybee Robotics has been one of four key Athena science payload instruments mounted on the mechanical arm of the Spirit, Opportunity and Curiosity Mars Exploration Rovers. Exposed rock surfaces weather and chemically alter over time. Although such weathered rock can present geological interest in itself, there is a limit to what can be learned. If the geological history of a landing site is to be constructed, then it is important to analyse the unweathered rock interior as clearly as possible. The rock abrasion tool's role is to substitute for a geologist's hammer, removing the weathered and chemically altered outer surface of rocks in order to view the pristine interior. The RAT uses a diamond resin standard common grinding technique, producing a 5mm depth grind with a relatively high surface roughness, achieved over a number of hours per grind and consumes approximately 11 watts of energy. This study assesses the benefits of using ultrasonic assisted grinding to improve surface smoothness. A prototype Micro-Optic UltraSonic Exfoliator (MOUSE) is tested on a range of rock types and demonstrates a number of advantages over the RAT. In addition to a smoother grind finish, these advantages include a lower rate of tool tip wear when using a tungsten carbide tip as opposed to diamond resin, less moving parts, a grind speed of minutes instead of hours, and a power consumption of only 1-5 Watts.

  18. Surface structure enhanced second harmonic generation in organic nanofibers

    DEFF Research Database (Denmark)

    Fiutowski, Jacek; Maibohm, Christian; Kostiucenko, Oksana

    Second-harmonic generation upon femto-second laser irradiation of nonlinearly optically active nanofibers grown from nonsymmetrically functionalized para-quarterphenylene (CNHP4) molecules is investigated. Following growth on mica templates, the nanofibers have been transferred onto lithography......-defined regular arrays of gold square nanostructures. These nanostructure arrays induce local field enhancement, which significantly lowers the threshold for second harmonic generation in the nanofibers....

  19. Teachers as Designers of Technology-Enhanced Outdoor Inquiry

    Directory of Open Access Journals (Sweden)

    Keren Sarah Levy

    2015-12-01

    Full Text Available Implementing inquiry in the outdoors introduces many challenges for teachers, some of which can be dealt with using mobile technologies. For productive use of these technologies, teachers should be provided with the opportunity to develop relevant knowledge and practices. In a professional development (PD program in this design-based research, 24 teachers were involved in adaptation of a learning environment supporting inquiry in the outdoors that included the use of mobile technologies. They first experienced the learning environment as learners, then adapted it for their own use, and finally, enacted the adapted environment with peers. We examined the scope and character of teacher involvement in adaptation, and the consequent professional growth, by analyzing observations, questionnaires, interviews and the adapted learning-environments. Findings indicate that all teachers demonstrated change processes, including changes in knowledge and practice, but the coherence of the learning environments decreased when substantial adaptations were made. Some teachers demonstrated professional growth, as reflected by their implementation of ideas learned in the PD program in their daily practice, long after the PD program had ended. This study demonstrates how the Teachers as Designers approach can support teacher learning and illustrates productive use of scaffolds for teacher growth and professional development.

  20. Cholesterol enhances surface water diffusion of phospholipid bilayers

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Chi-Yuan; Kausik, Ravinath; Han, Songi, E-mail: songi@chem.ucsb.edu [Department of Chemistry and Biochemistry and Materials Research Laboratory, University of California, Santa Barbara, California 93106 (United States); Olijve, Luuk L. C. [Laboratory of Macromolecular and Organic Chemistry and Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven (Netherlands)

    2014-12-14

    Elucidating the physical effect of cholesterol (Chol) on biological membranes is necessary towards rationalizing their structural and functional role in cell membranes. One of the debated questions is the role of hydration water in Chol-embedding lipid membranes, for which only little direct experimental data are available. Here, we study the hydration dynamics in a series of Chol-rich and depleted bilayer systems using an approach termed {sup 1}H Overhauser dynamic nuclear polarization (ODNP) NMR relaxometry that enables the sensitive and selective determination of water diffusion within 5–10 Å of a nitroxide-based spin label, positioned off the surface of the polar headgroups or within the nonpolar core of lipid membranes. The Chol-rich membrane systems were prepared from mixtures of Chol, dipalmitoyl phosphatidylcholine and/or dioctadecyl phosphatidylcholine lipid that are known to form liquid-ordered, raft-like, domains. Our data reveal that the translational diffusion of local water on the surface and within the hydrocarbon volume of the bilayer is significantly altered, but in opposite directions: accelerated on the membrane surface and dramatically slowed in the bilayer interior with increasing Chol content. Electron paramagnetic resonance (EPR) lineshape analysis shows looser packing of lipid headgroups and concurrently tighter packing in the bilayer core with increasing Chol content, with the effects peaking at lipid compositions reported to form lipid rafts. The complementary capability of ODNP and EPR to site-specifically probe the hydration dynamics and lipid ordering in lipid membrane systems extends the current understanding of how Chol may regulate biological processes. One possible role of Chol is the facilitation of interactions between biological constituents and the lipid membrane through the weakening or disruption of strong hydrogen-bond networks of the surface hydration layers that otherwise exert stronger repulsive forces, as reflected in

  1. IEngage: Using Technology to Enhance Students' Engagement in a Large Classroom

    Science.gov (United States)

    Sawang, Sukanlaya; O'Connor, Peter; Ali, Muhammad

    2017-01-01

    This paper aims to answer how we can increase students' engagement in a large class. We hypothesised that the use of KeyPad, an interactive student response system, can lead to enhanced student engagement in a large classroom. We tested a model of classroom technology integration enhancing the students' engagement among first year undergraduate…

  2. Applying Questioning or Reading Strategy to Review Technology Enhanced Coedited Notes of Elementary School Students

    Science.gov (United States)

    Chiu, Chiung-Hui; Cheng, Hsiao-Wei; Wu, Chiu-Yi

    2016-01-01

    The authors examined whether applying questioning review better enhances elementary level students' learning from technology-enhanced coediting-based note taking than does traditional reading review. A nonequivalent comparison group quasi-experimental design was implemented and replicated on four independent units. Two sixth grade elementary…

  3. Can Digital Technology Enhance Social Connectedness Among Older Adults? A Feasibility Study.

    Science.gov (United States)

    Barbosa Neves, Barbara; Franz, Rachel; Judges, Rebecca; Beermann, Christian; Baecker, Ron

    2017-11-01

    This study examined the feasibility of a novel communication technology to enhance social connectedness among older adults in residential care. Research suggests that technology can create opportunities for social connectedness, helping alleviate social isolation and loneliness. Studies on implementation and feasibility of such technological interventions, particularly among frail and institutionalized older adults, are scant. Data were gathered in a 3-month deployment with 12 older adults, including semistructured interviews with participants and relatives/friends, psychometric scales, field observations, and usability tests. Data were analyzed with qualitative profiling, thematic analysis, and Friedman tests. The technology was a feasible communication tool, although requiring an adaptation period. Use increased perceived social interaction with ties, but increased social connectedness (meaningful social interaction) was only reported by participants with geographically distant relatives. Sense of well-being and confidence with technology was enhanced, but negative effects were also observed. Findings are useful for researchers and practitioners interested in technological interventions.

  4. Enhancement of science and technology infrastructure, faculty development, and curriculum at Shaw University. Final performance report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    The two primary objectives of the proposal were (1) to enhance science and technology infrastructure, faculty development, and curriculum by integrating technology throughout science education programs of study, and (2) to increase faculty and students` knowledge of and skills in modern technologies that are designed to enhance the effectiveness of teaching and learning through education, research and communications. These two primary objectives have been accomplished through: Installation and operation of a technology-ready classroom; Upgrading CIS 200 Introduction to Computers; Upgrading all science laboratory courses to include integration of science and technology through installation of computers; Faculty development through attendance at workshops, seminars, or conferences related to technology applicable to sciences; and Undergraduate research internships at the Oak Ridge National Laboratory. The paper briefly discusses the outcome of implementing this proposal.

  5. Review of Speech-to-Text Recognition Technology for Enhancing Learning

    National Research Council Canada - National Science Library

    Rustam Shadiev; Wu-Yuin Hwang; Nian-Shing Chen; Yueh-Min Huang

    2014-01-01

    ...) technology has been applied to enhance learning. The first aim of this review is to understand how STR technology has been used to support learning over the past fifteen years, and the second is to analyze all research evidence to understand...

  6. Leveraging Computer-Mediated Communication Technologies to Enhance Interactions in Online Learning

    Science.gov (United States)

    Wright, Linda J.

    2011-01-01

    Computer-mediated communication (CMC) technologies have been an integral part of distance education for many years. They are found in both synchronous and asynchronous platforms and are intended to enhance the learning experience for students. CMC technologies add an interactive element to the online learning environment. The findings from this…

  7. Collaborative Professional Development in Higher Education: Developing Knowledge of Technology Enhanced Teaching

    Science.gov (United States)

    Jaipal-Jamani, Kamini; Figg, Candace; Gallagher, Tiffany; Scott, Ruth McQuirter; Ciampa, Katia

    2015-01-01

    This paper describes a professional development initiative for teacher educators, called the "Digital Pedagogies Collaboration," in which the goal was to build faculty knowledge about technology enhanced teaching (TPACK knowledge), develop a collaborative learning and research community of faculty members around technology enhanced…

  8. Enhancing the Students' Positive Attitude in Learning Business English by Using Technology

    Science.gov (United States)

    Agustina, Lia

    2017-01-01

    Many research findings have stated that the use of technology in EFL classroom results invaluable achievements and develops positive attitudes. Technology may integrate sounds, pictures, motions, and colors that fi ure out a natural picture of real life. The aim of the study was to enhance the students' attitude toward learning English by using…

  9. Teachers as Participatory Designers: Two Case Studies with Technology-Enhanced Learning Environments

    Science.gov (United States)

    Cober, Rebecca; Tan, Esther; Slotta, Jim; So, Hyo-Jeong; Könings, Karen D.

    2015-01-01

    Teachers are not typically involved as participatory designers in the design of technology-enhanced learning environments. As they have unique and valuable perspectives on the role of technology in education, it is of utmost importance to engage them in a participatory design process. Adopting a case study methodology, we aim to reveal in what…

  10. Museum Learning via Social and Mobile Technologies: (How) Can Online Interactions Enhance the Visitor Experience?

    Science.gov (United States)

    Charitonos, Koula; Blake, Canan; Scanlon, Eileen; Jones, Ann

    2012-01-01

    Key to introducing information and communication technologies in museums is to support meaning-making activity in encounters with artefacts. The study presented in this paper is exploratory in nature and investigates the use of social and mobile technologies in school field trips as a means of enhancing the visitor experience. It is anchored in…

  11. A Delphi Study on Technology Enhanced Learning (TEL) Applied on Computer Science (CS) Skills

    Science.gov (United States)

    Porta, Marcela; Mas-Machuca, Marta; Martinez-Costa, Carme; Maillet, Katherine

    2012-01-01

    Technology Enhanced Learning (TEL) is a new pedagogical domain aiming to study the usage of information and communication technologies to support teaching and learning. The following study investigated how this domain is used to increase technical skills in Computer Science (CS). A Delphi method was applied, using three-rounds of online survey…

  12. Transmission-type plasmonic sensor for surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Yanagisawa, Masahiro; Saito, Mikiko; Kunimoto, Masahiro; Homma, Takayuki

    2016-12-01

    We present a novel optical device for the analysis of chemical surface properties utilizing surface-enhanced Raman scattering. The device, a transmission-type plasmonic sensor (TPS), offers the advantages of high sensitivity, nondestructive sample characterization, simple setup, and low-cost fabrication. The TPS is composed of Ag nanoparticles (NPs) deposited on a convex quartz glass substrate. The enhanced Raman spectrum is acquired by focusing a laser beam perpendicular to the sample surface through the substrate. The laser beam generates plasmon polarization in droplet-shaped Ag NPs at the sensor/sample interface. Our results indicate the potential of the device as a versatile surface-analytical tool.

  13. Political Minimalism and Social Debates: The Case of Human-Enhancement Technologies.

    Science.gov (United States)

    Rodríguez-Alcázar, Javier

    2017-09-01

    A faulty understanding of the relationship between morality and politics encumbers many contemporary debates on human enhancement. As a result, some ethical reflections on enhancement undervalue its social dimensions, while some social approaches to the topic lack normative import. In this essay, I use my own conception of the relationship between ethics and politics, which I call "political minimalism," in order to support and strengthen the existing social perspectives on human-enhancement technologies.

  14. HealthCall for the smartphone: technology enhancement of brief intervention in HIV alcohol dependent patients

    OpenAIRE

    Hasin, Deborah S; Aharonovich, Efrat; Greenstein, Eliana

    2014-01-01

    Background Heavy drinking jeopardizes the health of patients in HIV primary care. In alcohol dependent patients in HIV primary care, a technological enhancement of brief intervention, HealthCall administered via interactive voice response (HealthCall-IVR) was effective at reducing heavy drinking. The smartphone offered a technology platform to improve HealthCall. Methods Working with input from patients, technology experts, and HIV clinic personnel, we further developed HealthCall, harnessing...

  15. Super-virtual Interferometric Separation and Enhancement of Back-scattered Surface Waves

    KAUST Repository

    Guo, Bowen

    2015-08-19

    Back-scattered surface waves can be migrated to detect near-surface reflectors with steep dips. A robust surface-wave migration requires the prior separation of the back-scattered surface-wave events from the data. This separation is often difficult to implement because the back-scattered surface waves are masked by the incident surface waves. We mitigate this problem by using a super-virtual interferometric method to enhance and separate the back-scattered surface waves. The key idea is to calculate the virtual back-scattered surface waves by stacking the resulting virtual correlated and convolved traces associated with the incident and back-scattered waves. Stacking the virtual back-scattered surface waves improves their signal-to-noise ratio and separates the back-scattered surface-waves from the incident field. Both synthetic and field data results validate the robustness of this method.

  16. Application of Anodization Process for Cast Aluminium Surface Properties Enhancement

    Directory of Open Access Journals (Sweden)

    Włodarczyk-Fligier A.

    2016-09-01

    Full Text Available An huge interest is observed in last years in metal matrix composite, mostly light metal based, which have found their applications in many industry branches, among others in the aircraft industry, automotive-, and armaments ones, as well as in electrical engineering and electronics, where one of the most important issue is related to the corrosion resistance, especially on the surface layer of the used aluminium alloys. This elaboration presents the influence of ceramic phase on the corrosion resistance, quality of the surface layer its thickness and structure of an anodic layer formed on aluminium alloys. As test materials it was applied the aluminium alloys Al-Si-Cu and Al-Cu-Mg, for which heat treatment processes and corrosion tests were carried out. It was presented herein grindability test results and metallographic examination, as well. Hardness of the treated alloys with those ones subjected to corrosion process were compared.

  17. Modification of polymer surfaces to enhance enzyme activity and stability

    DEFF Research Database (Denmark)

    Hoffmann, Christian

    already been developed, combining the same goal to improve enzyme activity, stability and selectivity. Polymer materials have shown, due to their easy processibility and versatile properties, high potential as enzyme support. However, in order to achieve improved enzyme performance, the combination...... of different factors, such as the nature of the enzyme, the properties of the support, the type of immobilization and the interaction between enzyme and support, has to be taken into consideration. In this thesis, these factors are pursued and addressed by exploiting various types of polymers with focus...... of immobilized enzymes. Micro-environmental changes were generated through the introduction of tailored surface functionalities via thiol-ene chemistry (TEC) and surface chain transfer free radical polymerization (SCT-FRP), which demonstrated a significant influence on the activity of immobilized horseradish...

  18. Enhanced Electron-Phonon Coupling at Metal Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Plummer, Ward E.

    2010-08-04

    The Born-Oppenheimer approximation (BOA) decouples electronic from nuclear motion, providing a focal point for most quantum mechanics textbooks. However, a multitude of important chemical, physical and biological phenomena are driven by violations of this approximation. Vibronic interactions are a necessary ingredient in any process that makes or breaks a covalent bond, for example, conventional catalysis or enzymatically delivered biological reactions. Metastable phenomena associated with defects and dopants in semiconductors, oxides, and glasses entail violation of the BOA. Charge exchange in inorganic polymers, organic slats and biological systems involves charge- induced distortions of the local structure. A classic example is conventional superconductivity, which is driven by the electron-lattice interaction. High-resolution angle-resolved photoemission experiments are yielding new insight into the microscopic origin of electron-phonon coupling (EPC) in anisotropic two-dimensional systems. Our recent surface phonon measurement on the surface of a high-Tc material clearly indicates an important momentum dependent EPC in these materials. In the last few years we have shifted our research focus from solely looking at electron phonon coupling to examining the structure/functionality relationship at the surface of complex transition metal compounds. The investigation on electron phonon coupling has allowed us to move to systems where there is coupling between the lattice, the electrons and the spin.

  19. Yield enhancement methodologies for 90-nm technology and beyond

    Science.gov (United States)

    Allgair, John; Carey, Todd; Dougan, James; Etnyre, Tony; Langdon, Nate; Murray, Brooke

    2006-03-01

    In order to stay competitive in the rapidly advancing international semiconductor industry, a manufacturing company needs to continually focus on several areas including rapid yield learning, manufacturing cost, statistical process control limits, process yield, equipment availability, cycle time, turns per direct labor hour, customer on time delivery and zero customer defects. To hold a competitive position in the semiconductor market, performance to these measurable factors mut be maintained regardless of the technology generation. In this presentation, the methodology applied by Freescale Semiconductor to achieve the fastest yield learning curve in the industry, as cited by Dr. Robert Leachman of UC Berkley in 2003, will be discussed.

  20. Enhancing the formation and shear resistance of nitrifying biofilms on membranes by surface modification

    DEFF Research Database (Denmark)

    Lackner, Susanne; Holmberg, Maria; Terada, Akihiko

    2009-01-01

    Polypropylene (PP) membranes and polyethylene (PE) surfaces were modified to enhance formation and shear resistance of nitrifying biofilms for wastewater treatment applications. A combination of plasma polymerization and wet chemistry was employed to ultimately introduce poly(ethyleneglycol) (PEG...

  1. Interfacing capillary electrophoresis and surface-enhanced resonance Raman spectroscopy for the determination of dye compounds

    NARCIS (Netherlands)

    Arraez Roman, D.; Efremov, E.V.; Ariese, F.; Segura Carretero, A.; Gooijer, C.

    2005-01-01

    The at-line coupling of capillary electrophoresis (CE) and surface-enhanced resonance Raman spectroscopy (SERRS) was optimized for the separation and subsequent spectroscopic identification of charged analytes (dye compounds). Raman spectra were recorded following deposition of the electropherogram

  2. Surface enhanced SHG from macrocycle, catenane and rotaxane thin films : experiments and theory.

    NARCIS (Netherlands)

    Arfaoui, I.; Bermudez, V.; De Nadai, C.; Jalkanen, J.-P.; Kajzar, F.; Leigh, D.A.; Lubomska, M.; Mendoza, S.M.; Niziol, J.; Rudolf, Petra; Zerbetto, F.; Grote, JG; Kaino, T; Kajzar, F

    2005-01-01

    Surface enhanced second harmonic generation experiments on supramolecules: macrocycles, catenanes and rotaxanes, monolayers and multilayers deposited by vacuum evaporation on silver layers are reported and described. The measurements show that the molecules are ordered in thin films. The highest

  3. From STEM to STEAM: Strategies for Enhancing Engineering & Technology Education

    Directory of Open Access Journals (Sweden)

    Andy M. Connor

    2015-05-01

    Full Text Available This paper sets out to challenge the common pedagogies found in STEM (Science, Technology, Engineering and Mathematics education with a particular focus on engineering. The dominant engineering pedagogy remains “chalk and talk”; despite research evidence that demonstrates its ineffectiveness. Such pedagogical approaches do not embrace the possibilities provided by more student-centric approaches and more active learning. The paper argues that there is a potential confusion in engineering education around the role of active learning approaches, and that the adoption of these approaches may be limited as a result of this confusion, combined with a degree of disciplinary egocentrism. The paper presents examples of design, engineering and technology projects that demonstrate the effectiveness of adopting pedagogies and delivery methods more usually attributed to the liberal arts such as studio based learning. The paper concludes with some suggestions about how best to create a fertile environment from which inquiry based learning can emerge as well as a reflection on whether the only real limitation on cultivating such approaches is the disciplinary egocentrism of traditional engineering educators.

  4. STORIES OF TECHNOLOGY-ENHANCEMENT IN HIGHER EDUCATION – A CRITICAL APPROACH

    Directory of Open Access Journals (Sweden)

    Trine Fossland

    2016-11-01

    Full Text Available There is a large body of research on technology-enhanced learning, but questions related to the educational effectiveness of technology use still needs to be questioned. In this paper, I argue that digital innovators’ stories about technology enhancement may constitute a rich source for understanding this complex educational phenomenon both in relation to teachers’ daily practices and the implementation of ICT in higher education at large. Based on biographical interviews with “digital innovators”, the aim of this paper is to investigate how [their] digital competence is used to enhance teaching and learning in higher education. This paper asks; how do digital innovators approach the use of ICT to enhance students’ learning and what are the organisational conditions for this approach? The findings suggests that technology-enhancement is linked to nine key characteristics: different educational models, authenticity, pedagogical added values, meaningful student activities, changing approaches to feedback, assessment and connection with the outside world, as well as holistic planning, supportive leaders and strong micro-cultures. This paper proposes a more nuanced understanding of the term technology enhanced learning and suggests strategies for educational development and further investigations related to this phenomenon in higher education.

  5. Enhanced surface photochemistry in chloride-nitrate ion mixtures.

    Science.gov (United States)

    Wingen, Lisa M; Moskun, Amy C; Johnson, Stanley N; Thomas, Jennie L; Roeselová, Martina; Tobias, Douglas J; Kleinman, Michael T; Finlayson-Pitts, Barbara J

    2008-10-01

    Heterogeneous reactions of sea salt aerosol with various oxides of nitrogen lead to replacement of chloride ion by nitrate ion. Studies of the photochemistry of a model system were carried out using deliquesced mixtures of NaCl and NaNO3 on a Teflon substrate. Varying molar ratios of NaCl to NaNO3 (1 : 9 Cl- : NO3-, 1 : 1 Cl- : NO3-, 3 : 1 Cl- : NO3-, 9 : 1 Cl- : NO3-) and NaNO3 at the same total concentration were irradiated in air at 299 +/- 3 K and at a relative humidity of 75 +/- 8% using broadband UVB light (270-380 nm). Gaseous NO2 production was measured as a function of time using a chemiluminescence NO(y) detector. Surprisingly, an enhanced yield of NO2 was observed as the chloride to nitrate ratio increased. Molecular dynamics (MD) simulations show that as the Cl- : NO3- ratio increases, the nitrate ions are drawn closer to the interface due to the existence of a double layer of interfacial Cl- and subsurface Na+. This leads to a decreased solvent cage effect when the nitrate ion photodissociates to NO2+O*-, increasing the effective quantum yield and hence the production of gaseous NO2. The implications of enhanced NO2 and likely OH production as sea salt aerosols become processed in the atmosphere are discussed.

  6. Multiobjective evolutionary optimisation for surface-enhanced Raman scattering.

    Science.gov (United States)

    Jarvis, Roger M; Rowe, William; Yaffe, Nicola R; O'Connor, Richard; Knowles, Joshua D; Blanch, Ewan W; Goodacre, Royston

    2010-07-01

    In most optimisation experiments, a single parameter is first optimised before a second and then third one are subsequently modified to give the best result. By contrast, we believe that simultaneous multiobjective optimisation is more powerful; therefore, an optimisation of the experimental conditions for the colloidal SERS detection of L-cysteine was carried out. Six aggregating agents and three different colloids (citrate, borohydride and hydroxylamine reduced silver) were tested over a wide range of concentrations for the enhancement and the reproducibility of the spectra produced. The optimisation was carried out using two methods, a full factorial design (FF, a standard method from the experimental design literature) and, for the first time, a multiobjective evolutionary algorithm (MOEA), a method more usually applied to optimisation problems in computer science. Simulation results suggest that the evolutionary approach significantly out-performs random sampling. Real experiments applying the evolutionary method to the SERS optimisation problem led to a 32% improvement in enhancement and reproducibility compared with the FF method, using far fewer evaluations.

  7. Image enhancement and understanding for remote visual inspection of aircraft surface

    Science.gov (United States)

    Gunatilake, Priyan; Siegel, Mel; Jordan, Angel G.; Podnar, Gregg W.

    1996-11-01

    We describe a library of image enhancement and understanding algorithms developed to enhance and recognize surface defects from remote live imagery of an aircraft surface. Also described are the supporting mobile robot platform that generates the remote stereoscopic imagery and the inspection console containing a graphical user interface, through which the inspector accesses the live imagery for remote inspection. We will discuss initial results of the remote imaging process and the image processing library, and speculate on their future application in aircraft inspection.

  8. Grander system: a new technology to reduce surface tension of adhesive systems in dentistry.

    Science.gov (United States)

    Gonçalves, Sérgio Eduardo de Paiva; Cruz, Nilson; Brayner, Ricardo; Huhtala, Maria Filomena Rocha Lima; Borges, Alessandra Bühler; Barcellos, Daphne Câmara

    2014-01-01

    Reduced surface tension of liquids results in higher surface wetting ability and diffusivity by the substrate. The objective of this study was to evaluate the influence of the Grander Technology in reducing the surface tension of adhesive systems. Two adhesive systems (self-etch and total-etch) were modified by physical contact with the Grander system Flexible unit to revitalize water, for 48 h. Surface tension of adhesive systems and water in normal and grander-modified conditions was measured with a goniometer. The results showed a reduction of surface tension for all conditions grander-modified between 3-15%. Grander Technology was effective in reducing the surface tension of the Single Bond and Clearfil SE Bond adhesive systems. Clinical significance. Grander technology was employed to restructure the molecular structure of water-based adhesive systems, which can increase their wetness capacity and therefore ensure a greater diffusibility.

  9. Disruptive Technology Enhanced Learning: The Use and Misuse of Digital Technologies in Higher Education

    Science.gov (United States)

    Flavin, Michael

    2017-01-01

    This book is about how technologies are used in practice to support learning and teaching in higher education. Despite digitization and e-learning becoming ever-increasingly popular in university teaching settings, this book convincingly argues instead in favour of simple and convenient technologies, thus disrupting traditional patterns of…

  10. Surface-enhanced Raman spectroscopy on novel black silicon-based nanostructured surfaces

    DEFF Research Database (Denmark)

    Talian, Ivan; Mogensen, Klaus Bo; Orinak, A.

    2009-01-01

    , effects of Ti and Ti/Pt adhesion layers underneath the gold layers on the analytical signal enhancement were tested. An enhancement factor of 7.6 x 10(7) with the excitation laser 785 nm was achieved for the tested analyte, Rhodamine 6G, and non-resonance SER spectra were recorded in a 5 s acquisition...

  11. Plasma Surface Modification of Glass-Fibre-Reinforced Polyester Enhanced by Ultrasonic Irradiation

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Singh, Shailendra Vikram; Bardenshtein, Alexander

    2010-01-01

    .295, 0.385 and 0.447, respectively. This indicated that the plasma treatment oxidized and roughened the GFRP surface, and the ultrasonic irradiation further enhanced the oxidation. It is concluded that plasma treatment efficiency for adhesion improvement of GFRPs is enhanced by the ultrasonic irradiation.......During atmospheric pressure plasma treatment, reactive species generated in the plasma diffuse through a boundary gas layer which is adsorbed at the material surface. Many of the reactive species become inactivated before reaching the surface due to their short lifetime. The efficiency of plasma...... treatment can be highly enhanced by simultaneous high-power ultrasonic irradiation of the treating surface, because the delivered acoustic energy can reduce the thickness of the boundary gas layer. Here surfaces of glass-fibre-reinforced polyester (GFRP) plates were treated using an atmospheric pressure...

  12. Self-referenced directional enhanced Raman scattering using plasmon waveguide resonance for surface and bulk sensing

    Science.gov (United States)

    Wan, Xiu-mei; Gao, Ran; Lu, Dan-feng; Qi, Zhi-mei

    2018-01-01

    Surface plasmon-coupled emission has been widely used in fluorescence imaging, biochemical sensing, and enhanced Raman spectroscopy. A self-referenced directional enhanced Raman scattering for simultaneous detection of surface and bulk effects by using plasmon waveguide resonance (PWR) based surface plasmon-coupled emission has been proposed and experimentally demonstrated. Raman scattering was captured on the prism side in Kretschmann-surface plasmon-coupled emission. The distinct penetration depths (δ) of the evanescent field for the transverse electric (TE) and transverse magnetic (TM) modes result in different detected distances of the Raman signal. The experimental results demonstrate that the self-referenced directional enhanced Raman scattering of the TE and TM modes based on the PWR can detect and distinguish the surface and bulk effects simultaneously, which appears to have potential applications in researches of chemistry, medicine, and biology.

  13. Development of Surface Modification Techniques for Enhanced Safety of Light Water Reactors: Recent Progress and Future Direction at THLAB

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Gwang Hyeok; Jeong, Ui Ju; Son, Hong Hyun; Jeun, Gyoo Dong; Kim, Sung Joong [Hanyang University, Daejeon (Korea, Republic of)

    2016-05-15

    They concluded that the CHF enhancement in nanofluid boiling was mainly affected by the surface characteristics of the developed layer. Furthermore, an introduction of surface modification can be utilized to secure the safety of nuclear reactor systems. At many components of the reactor systems, energetic boiling heat transfer occurs, and potential thermal attack to the systems is expected under normal or accident environments. In particular, during a reactor operation, fission energy is deposited in the fuel assemblies in a core. Also, under severe conditions, failure of a reactor vessel may occur by high temperature molten materials. In this article, we introduce the surface modification techniques and recent achievements. After a brief description of each deposition mechanism, an assessment of thermal margin for both the technologies is discussed based on pool boiling experiments conducted at THLAB. Moreover, in the latter part of each chapter, experimental facilities for applied heat transfer tests to consider reactor environments are presented.

  14. Flexible and Adhesive Surface Enhance Raman Scattering Active Tape for Rapid Detection of Pesticide Residues in Fruits and Vegetables.

    Science.gov (United States)

    Chen, Jiaming; Huang, Youju; Kannan, Palanisamy; Zhang, Lei; Lin, Zhenyu; Zhang, Jiawei; Chen, Tao; Guo, Longhua

    2016-02-16

    The efficient extraction of targets from complex surfaces is vital for technological applications ranging from environmental pollutant monitoring to analysis of explosive traces and pesticide residues. In our present study, we proposed a proof-of-concept surface enhance Raman scattering (SERS) active substrate serving directly to the rapid extraction and detection of target molecules. The novel substrate was constructed by decorating the commercial tape with colloidal gold nanoparticles (Au NPs), which simultaneously provides SERS activity and "sticky" of adhesive. The utility of SERS tape was demonstrated by directly extracting pesticide residues in fruits and vegetables via a simple and viable "paste and peel off" approach. The obtained strong and easily distinguishable SERS signals allow us to detect various pesticide residues such as parathion-methyl, thiram, and chlorpyrifos in the real samples with complex surfaces including green vegetable, cucumber, orange, and apple.

  15. Enhanced propellant performance via environmentally friendly curable surface coating

    Directory of Open Access Journals (Sweden)

    Thelma Manning

    2017-06-01

    Full Text Available Surface coating of granular propellants is widely used in a multiplicity of propellants for small, medium and large caliber ammunition. All small caliber ball propellants exhibit burning progressivity due to application of effective deterrent coatings. Large perforated propellant grains have also begun utilizing plasticizing and impregnated deterrent coatings with the purpose of increasing charge weights for greater energy and velocity for the projectile. The deterrent coating and impregnation process utilizes volatile organic compounds (VOCs and hazardous air pollutants (HAPs which results in propellants that need to be forced air dried which impacts air quality. Propellants undergo temperature fluctuations during their life. Diffusion coefficients vary exponentially with variations in temperature. A small temperature increase can induce a faster migration, even over a short period of time, which can lead to large deviations in the concentration. This large concentration change in the ammunition becomes a safety or performance liability. The presence of both polymeric deterrents and nitroglycerin(NG in the nitrocellulose matrix and organic solvents leads to higher diffusion rates. This results in continued emissions of VOCs and HAPs. Conventional polymers tend to partition within the propellant matrix. In other words, localized mixing can occur between the polymer and underlying propellant. This is due to solvent induced softening of the polymer vehicle over the propellant grain. In effect this creates a path where migration can occur. Since nitrate esters, like NG, are relatively small, it can exude to the surface and create a highly unstable and dangerous situation for the warfighter. Curable polymers do not suffer from this partitioning due to “melting” because no VOC solvents are present. They remain surface coated. The small scale characterization testing, such as closed bomb testing, small scale sensitivity, thermal stability, and

  16. Surface- and Tip-Enhanced Raman Spectroscopy as Operando Probes for Monitoring and Understanding Heterogeneous Catalysis

    NARCIS (Netherlands)

    Harvey, Clare E.; Weckhuysen, Bert M.

    Surface-enhanced Raman spectroscopy (SERS) and tip-enhanced Raman spectroscopy (TERS) were until recently limited in their applicability to the majority of heterogeneous catalytic reactions. Recent developments begin to resolve the conflicting experimental requirements for SERS and TERS on the one

  17. Nanostructure design for surface-enhanced Raman spectroscopy - prospects and limits

    DEFF Research Database (Denmark)

    Xiao, Sanshui; Mortensen, Niels Asger; Jauho, Antti-Pekka

    2008-01-01

    Surface-enhanced Raman spectroscopy (SERS) allows single-molecule detection due to the strong field localization occurring at sharp bends or kinks of the metal-vacuum interface. An important question concerns the limits of the signal enhancement that can be achieved via a judicious design...

  18. Enhanced bio-manufacturing through advanced multivariate statistical technologies.

    Science.gov (United States)

    Martin, E B; Morris, A J

    2002-11-13

    The paper describes the interrogation of data, from a reaction vessel producing an active pharmaceutical ingredient (API), using advanced multivariate statistical techniques. Due to the limited number of batches available, data augmentation was used to increase the number of batches thereby enabling the extraction of more subtle process behaviour from the data. A second methodology investigated was that of multi-group modelling. This allowed between cluster variability to be removed, thus allowing attention to focus on within process variability. The paper describes how the different approaches enabled the realisation of a better understanding of the factors causing the onset of an impurity formation to be obtained as well demonstrating the power of multivariate statistical data analysis techniques to provide an enhanced understanding of the process.

  19. Responsivity Enhanced NMOSFET Photodetector Fabricated by Standard CMOS Technology

    Directory of Open Access Journals (Sweden)

    Fuwei Wu

    2015-01-01

    Full Text Available Increasing the responsivity is one of the important issues for a photodetector. In this paper, we demonstrate an improved NMOSFET photodetector by using deep-n-well (DNW structure which can improve the responsivity of the photodetector significantly. The experimental results show that the responsivity can be enhanced greatly by the DNW structure and is much larger than the previous work when DNW is biased with 0.5 V, while the dark current exhibits almost no increase. Further characterization indicates that the diode formed by the bulk and DNW can efficiently absorb photons and has a large gain factor of the photocurrent especially under low light condition, which gives a more promising application for the detector to detect the weak light.

  20. Enhancing performance and reducing stress in sports technological advances

    CERN Document Server

    Ivancevic, Tijana; Greenberg, Ronald

    2015-01-01

    This book is designed to help athletes and individuals interested in high sports performance in their journey towards the perfection of human sports abilities and achievements. It has two main goals: accelerating the acquisition of motor skills and preparing and vigilantly reducing the recovery time after training and competition. The Diamond Sports Protocol (DSP) presents state-of-the-art techniques for current sport and health technologies, particularly neuromuscular electrical stimulation (Sports Wave), oxygen infusion (Oxy Sports), infrared (Sports Infrared Dome) and lactic acid cleaning (Turbo Sports). The book suggest DSP as an essential part of every future athlete's training, competition and health maintenance. The book is for everyone interested in superior sports performance, fast and effective rehabilitation from training and competition and sports injury prevention.

  1. Using Communication Technology to Enhance Interprofessional Education Simulations.

    Science.gov (United States)

    Shrader, Sarah; Kostoff, Matthew; Shin, Tiffany; Heble, Annie; Kempin, Brian; Miller, Astyn; Patykiewicz, Nick

    2016-02-25

    To determine the impact of simulations using an alternative method of communication on students' satisfaction, attitudes, confidence, and performance related to interprofessional communication. One hundred sixty-three pharmacy students participated in a required applications-based capstone course. Students were randomly assigned to one of three interprofessional education (IPE) simulations with other health professions students using communication methods such as telephone, e-mail, and video conferencing. Pharmacy students completed a validated survey instrument, Attitude Toward Healthcare Teams Scale (ATHCTS) prior to and after course participation. Significant positive changes occurred for 5 out of 20 items. Written reflection papers and student satisfaction surveys completed after participation showed positive themes and satisfaction. Course instructors evaluated student performance using rubrics for formative feedback. Implementation of IPE simulations using various methods of communication technology is an effective way for pharmacy schools to incorporate IPE into their curriculum.

  2. Technology Development for Nickel X-Ray Optics Enhancement

    Science.gov (United States)

    Bubarev, Mikhail; Ramsey, Brian; Engelhaupt, Darell

    2008-01-01

    We are developing grazing-incidence x-ray optics for high-energy astrophysics using the electroform-nickel replication process. In this process, mirror shells are fabricated by replication off super-polished cylindrical mandrels. The mirrors fabricated using this process have a demonstrated optical performance at the level of 11-12 arc seconds resolution (HPD) for 30 keV x rays. Future missions demand ever higher angular resolutions and this places stringent requirements on the quality of the mandrels, the precision of the metrology, and the mounting and alignment of the mirror shells in their housings. A progress report on recent technology developments in all these areas will be presented along with a discussion on possible post fabrication, in-situ improvement of the x-ray mirrors quality.

  3. From computer images to video presentation: Enhancing technology transfer

    Science.gov (United States)

    Beam, Sherilee F.

    1994-01-01

    With NASA placing increased emphasis on transferring technology to outside industry, NASA researchers need to evaluate many aspects of their efforts in this regard. Often it may seem like too much self-promotion to many researchers. However, industry's use of video presentations in sales, advertising, public relations and training should be considered. Today, the most typical presentation at NASA is through the use of vu-graphs (overhead transparencies) which can be effective for text or static presentations. For full blown color and sound presentations, however, the best method is videotape. In fact, it is frequently more convenient due to its portability and the availability of viewing equipment. This talk describes techniques for creating a video presentation through the use of a combined researcher and video professional team.

  4. Applying WEPP technologies to western alkaline surface coal mines

    Science.gov (United States)

    J. Q. Wu; S. Dun; H. Rhee; X. Liu; W. J. Elliot; T. Golnar; J. R. Frankenberger; D. C. Flanagan; P. W. Conrad; R. L. McNearny

    2011-01-01

    One aspect of planning surface mining operations, regulated by the National Pollutant Discharge Elimination System (NPDES), is estimating potential environmental impacts during mining operations and the reclamation period that follows. Practical computer simulation tools are effective for evaluating site-specific sediment control and reclamation plans for the NPDES....

  5. Tunable gold nanostars for surface enhanced Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Giorgetti, Emilia; Trigari, Silvana; Margheri, Giancarlo; Sottini, Stefano [Institute of Complex Systems CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze (Italy); Rindi, Alessio; Dellepiane, Giovanna [Department of Chemistry and Industrial Chemistry, University of Genova, Genova (Italy); Brusatin, Giovanna; Brigo, Laura [Department of Mechanical Engineering, University of Padova, Padova (Italy); Muniz-Miranda, Maurizio [Department of Chemistry ' ' Ugo Schiff' ' , University of Firenze, Sesto Fiorentino, Firenze (Italy); Timtcheva, Iljiana [Institute of Organic Chemistry with Centre of Phytochemistry Bulgarian Academy of Sciences, Sofia (Bulgaria)

    2012-06-15

    We fabricated stable gold nanostars (AuNSs) with tunable extinction properties from the visible spectral region up to 1800 nm, depending on the average values of core size and branch length. The results of their UV-Vis and transmission electron microscopy characterization are compared with computational data from finite elements method, which makes use of an approximated model of the branched structures. The theoretical computations put in evidence the existence of hot spots located on the tips of the nanostars even up to 1800 nm wavelength, which opens the way to the improvement of diagnostics in the IR region. Preliminary Fourier transform Raman experiments performed after functionalization with a fluorescent dye bearing end thiol groups seem to confirm the field enhancing capability of the nanostructures at 1064 nm. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Effects of voice enhancement technology and relaxing music on the frequency of imagery among break dancers.

    Science.gov (United States)

    Karageorghis, Costas I; Smith, Danielle L; Priest, David-Lee

    2012-03-01

    A device was developed in 2008 by Hypnoke International Ltd. for use by performance consultants and hypnotherapists. It enhances a practitioner's voice and blocks out auditory distractions while delivering imagery inductions, thereby increasing their effectiveness. This study examined the impact of voice-enhancement technology and relaxing music on the frequency of imagery experienced by a sample of elite British break dancers (N = 20; mean age = 26.5 years, SD = 1.5 years). An imagery script was administered to participants under four conditions: voice enhancement with music, voice enhancement only, a music-only control, and a no-voice-enhancement-and-no-music control. Frequency of imagery was assessed using the Sport Imagery Questionnaire. There was a higher incidence of imagery in the voice enhancement with music, voice enhancement only, and music-only conditions when compared to the no-voice-enhancement-and-no-music control. The key finding was that imagery was most frequent when voice enhancement was combined with music in a complementary manner. Thus, it is concluded that the use of voice enhancement technology can improve the efficacy of relaxation and imagery training for break dancers, and potentially, dancers in general.

  7. Using Web 2.0 Technology to Enhance, Scaffold and Assess Problem-Based Learning

    Directory of Open Access Journals (Sweden)

    Catherine Hack

    2013-08-01

    Full Text Available Web 2.0 technologies, such as social networks, wikis, blogs, and virtual worlds provide a platform for collaborative working, facilitating sharing of resources and joint document production. They can act as a stimulus to promote active learning and provide an engaging and interactive environment for students, and as such align with the philosophy of Problem-based Learning. Furthermore, Web 2.0 technologies can provide the tutor or facilitator with an opportunity to scaffold and asses the PBL process. However, whilst it is recognised that technology has an important role in enhancing each step of a PBL exercise, academic staff can be reluctant to use it. This paper provides some illustrative examples of the technologies that have been used to enhance, scaffold and assess PBL and their evaluation by distance learning and on-campus students at the University of Ulster. The benefits and limitations of using technology for both staff and students to support PBL are discussed.

  8. Surface-enhanced Raman spectroscopy of bipyridines and phenylpyridines

    Energy Technology Data Exchange (ETDEWEB)

    Strekas, T.C.; Diamandopoulos, P.S. (City Univ. of New York, Flushing (USA))

    1990-03-08

    Raman and SERS spectra in the region 700-3150 cm{sup {minus}1} are reported for 2,2{prime}-, 3,3{prime}-, 4,4{prime}-, 2,3{prime}-, and 2,4{prime}-bipyridines and for 2-, 3-, and 4-phenylpyridines. Spectra for 4,4{prime}-dimethyl-2,2{prime}-bipyridine, 1,10-phenanthroline, and N-methyl-4,4{prime}-bipyridinium are also reported. Comparison of the Raman and SERS spectra, and, in particular, analysis of the C-H stretching frequencies and intensities, indicates that in all cases except 2-phenylpyridine the molecules sit perpendicular to the sol surface consistent with {sigma} donation from the less sterically hindered nitrogen donor atom and an all-planar structure.

  9. Enhancements to surface drifters enabled by AtlantOS

    Science.gov (United States)

    Poli, Paul; Reverdin, Gilles; Bourlès, Bernard; Carval, Thierry; David, Arnaud

    2017-04-01

    This paper reviews the improvements enabled by the H2020 project AtlantOS on the drifter network observing capacity and data integration. A first improvement is the recurrent deployment of drifters since 2015 in the Tropical Atlantic. The work presented will show the value of the additional surface pressure observations collected by these drifters, for numerical weather prediction and climate reanalysis. A second improvement is the development of a cost-effective temperature and conductivity sensor for drifters. A new sensor has been developed and implemented on a prototype drifter. A third improvement is the definition of a Global Data Assembly Center in the framework of the Marine Climate Data System. The GDAC will serve as global integrator of drifter data and metadata, and consolidate both near-real-time and delayed mode (improved or reprocessed) data feeds. The architecture proposed for this GDAC will be presented to collect feed-back.

  10. Porous surface modified bioactive bone cement for enhanced bone bonding.

    Directory of Open Access Journals (Sweden)

    Qiang He

    Full Text Available Polymethylmethacrylate bone cement cannot provide an adhesive chemical bonding to form a stable cement-bone interface. Bioactive bone cements show bone bonding ability, but their clinical application is limited because bone resorption is observed after implantation. Porous polymethylmethacrylate can be achieved with the addition of carboxymethylcellulose, alginate and gelatin microparticles to promote bone ingrowth, but the mechanical properties are too low to be used in orthopedic applications. Bone ingrowth into cement could decrease the possibility of bone resorption and promote the formation of a stable interface. However, scarce literature is reported on bioactive bone cements that allow bone ingrowth. In this paper, we reported a porous surface modified bioactive bone cement with desired mechanical properties, which could allow for bone ingrowth.The porous surface modified bioactive bone cement was evaluated to determine its handling characteristics, mechanical properties and behavior in a simulated body fluid. The in vitro cellular responses of the samples were also investigated in terms of cell attachment, proliferation, and osteoblastic differentiation. Furthermore, bone ingrowth was examined in a rabbit femoral condyle defect model by using micro-CT imaging and histological analysis. The strength of the implant-bone interface was also investigated by push-out tests.The modified bone cement with a low content of bioactive fillers resulted in proper handling characteristics and adequate mechanical properties, but slightly affected its bioactivity. Moreover, the degree of attachment, proliferation and osteogenic differentiation of preosteoblast cells was also increased. The results of the push-out test revealed that higher interfacial bonding strength was achieved with the modified bone cement because of the formation of the apatite layer and the osseointegration after implantation in the bony defect.Our findings suggested a new bioactive

  11. FDTD/TDSE study of surface-enhanced infrared absorption by metal nanoparticles.

    Energy Technology Data Exchange (ETDEWEB)

    Chang, S.-H.; Schatz, G. C.; Gray, S. K.; Chemistry; Northwestern Univ.; National Cheng-Kung Univ.

    2006-01-01

    We study surface-enhanced infrared absorption, including multiphoton processes, due to the excitation of surface plasmons on metal nanoparticles. The time-dependent Schroedinger equation and finite-difference time-domain method are self-consistently coupled to treat the problem.

  12. Surface-Enhanced Raman Scattering of the Complexes of Silver with Adenine and dAMP

    NARCIS (Netherlands)

    Otto, Cornelis; Hoeben, F.P.; Hoeben, F.P.; Greve, Jan

    1991-01-01

    The behaviour of adenine and 2'-deoxyadenosine-5'-monophosphate (dAMP) at positive surface potentials of a silver working electrode was investigated using surface-enhanced Raman scattering (SERS). The use of positive potentials in the presence of adenine or dAMP leads to a rapid accumulation of an

  13. Enhanced Display of Lipase on the Escherichia coli Cell Surface, Based on Transcriptome Analysis▿ †

    Science.gov (United States)

    Baek, Jong Hwan; Han, Mee-Jung; Lee, Seung Hwan; Lee, Sang Yup

    2010-01-01

    A cell surface display system was developed using Escherichia coli OmpC as an anchoring motif. The fused Pseudomonas fluorescens SIK W1 lipase was successfully displayed on the surface of E. coli cells, and the lipase activity could be enhanced by the coexpression of the gadBC genes identified by transcriptome analysis. PMID:19948866

  14. Polymer membrane with a mineral coating for enhanced curling resistance and surface wettability.

    Science.gov (United States)

    Yang, Hao-Cheng; Chen, Yi-Fu; Ye, Chen; Jin, Yi-Ning; Li, Hanying; Xu, Zhi-Kang

    2015-08-18

    Zirconia-wrapped membranes were fabricated via a mineralization process on polydopamine/polyethyleneimine-deposited surfaces. The rigid and hydrophilic mineral coating simultaneously endows the membranes with enhanced curling resistance and surface wettability, enabling the membranes to separate oil-in-water emulsions.

  15. Plasma Treatment Maintains Surface Energy of the Implant Surface and Enhances Osseointegration

    Directory of Open Access Journals (Sweden)

    Fernando P. S. Guastaldi

    2013-01-01

    Full Text Available The surface energy of the implant surface has an impact on osseointegration. In this study, 2 surfaces: nonwashed resorbable blasting media (NWRBM; control and Ar-based nonthermal plasma 30 days (Plasma 30 days; experimental, were investigated with a focus on the surface energy. The surface energy was characterized by the Owens-Wendt-Rabel-Kaelble method and the chemistry by X-ray photoelectron spectroscopy (XPS. Five adult beagle dogs received 8 implants (n=2 per surface, per tibia. After 2 weeks, the animals were euthanized, and half of the implants (n=20 were removal torqued and the other half were histologically processed (n=20. The bone-to-implant contact (BIC and bone area fraction occupancy (BAFO were evaluated on the histologic sections. The XPS analysis showed peaks of C, Ca, O, and P for the control and experimental surfaces. While no significant difference was observed for BIC parameter (P>0.75, a higher level for torque (P<0.02 and BAFO parameter (P<0.01 was observed for the experimental group. The surface elemental chemistry was modified by the plasma and lasted for 30 days after treatment resulting in improved biomechanical fixation and bone formation at 2 weeks compared to the control group.

  16. Immersion Condensation on Oil-Infused Heterogeneous Surfaces for Enhanced Heat Transfer

    Science.gov (United States)

    Xiao, Rong; Miljkovic, Nenad; Enright, Ryan; Wang, Evelyn N.

    2013-01-01

    Enhancing condensation heat transfer is important for broad applications from power generation to water harvesting systems. Significant efforts have focused on easy removal of the condensate, yet the other desired properties of low contact angles and high nucleation densities for high heat transfer performance have been typically neglected. In this work, we demonstrate immersion condensation on oil-infused micro and nanostructured surfaces with heterogeneous coatings, where water droplets nucleate immersed within the oil. The combination of surface energy heterogeneity, reduced oil-water interfacial energy, and surface structuring enabled drastically increased nucleation densities while maintaining easy condensate removal and low contact angles. Accordingly, on oil-infused heterogeneous nanostructured copper oxide surfaces, we demonstrated approximately 100% increase in heat transfer coefficient compared to state-of-the-art dropwise condensation surfaces in the presence of non-condensable gases. This work offers a distinct approach utilizing surface chemistry and structuring together with liquid-infusion for enhanced condensation heat transfer. PMID:23759735

  17. Structural Origin of Enhanced Dynamics at the Surface of a Glassy Alloy

    Science.gov (United States)

    Sun, Gang; Saw, Shibu; Douglass, Ian; Harrowell, Peter

    2017-12-01

    The enhancement of mobility at the surface of an amorphous alloy is studied using a combination of molecular dynamic simulations and normal mode analysis of the nonuniform distribution of Debye-Waller factors. The increased mobility at the surface is found to be associated with the appearance of Arrhenius temperature dependence. We show that the transverse Debye-Waller factor exhibits a peak at the surface. Over the accessible temperature range, we find that the bulk and surface diffusion coefficients obey the same empirical relationship with the respective Debye-Waller factors. Extrapolating this relationship to lower T , we argue that the observed decrease in the constraint at the surface is sufficient to account for the experimentally observed surface enhancement of mobility.

  18. Supporting technology for enhanced oil recovery for thermal processes

    Energy Technology Data Exchange (ETDEWEB)

    Reid, T.B.; Bolivar, J.

    1997-12-01

    This report contains the results of efforts under the six tasks of the Ninth Amendment and Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Agreement. The report is presented in sections (for each of the 6 tasks) and each section contains one or more reports prepared by various individuals or groups describing the results of efforts under each of the tasks. A statement of each task, taken from the agreement, is presented on the first page of each section. The tasks are numbered 62 through 67. The first, second, third, fourth fifth, sixth, seventh, eighth, and ninth reports on Annex IV, [Venezuela MEM/USA-DOE Fossil Energy Report IV-1, IV-2, IV-3, IV-4, IV-5, IV-6, IV-7, and IV-8 (DOE/BETC/SP-83/15, DOE/BC-84/6/SP, DOE/BC-86/2/SP, DOE/BC-87/2/SP, DOE/BC-90/1/SP, DOE/BC-90/1/SP) (DOE/BC-92/1/SP, DOE/BC-93/3/SP, and DOE/BC-95/3/SP)] contain the results from the first 61 tasks. Those reports are dated April 1983, August 1984, March 1986, July 1987, November 1988, October 1991, February 1993, and March 1995 respectively.

  19. Enhancing Assisted Living Technology with Extended Visual Memory

    Directory of Open Access Journals (Sweden)

    Joo-Hwee Lim

    2011-05-01

    Full Text Available Human vision and memory are powerful cognitive faculties by which we understand the world. However, they are imperfect and further, subject to deterioration with age. We propose a cognitive-inspired computational model, Extended Visual Memory (EVM, within the Computer-Aided Vision (CAV framework, to assist human in vision-related tasks. We exploit wearable sensors such as cameras, GPS and ambient computing facilities to complement a user's vision and memory functions by answering four types of queries central to visual activities, namely, Retrieval, Understanding, Navigation and Search. Learning of EVM relies on both frequency-based and attention-driven mechanisms to store view-based visual fragments (VF, which are abstracted into high-level visual schemas (VS, both in the visual long-term memory. During inference, the visual short-term memory plays a key role in visual similarity computation between input (or its schematic representation and VF, exemplified from VS when necessary. We present an assisted living scenario, termed EViMAL (Extended Visual Memory for Assisted Living, targeted at mild dementia patients to provide novel functions such as hazard-warning, visual reminder, object look-up and event review. We envisage EVM having the potential benefits in alleviating memory loss, improving recall precision and enhancing memory capacity through external support.

  20. Supercritical fluid technology for enhanced drug delivery and heterogeneous catalysis

    Science.gov (United States)

    Pathak, Pankaj

    In recent years there has been great interest in the properties of supercritical fluids (SCFs) and applications of supercritical fluid technology in chemistry, material sciences and many other areas. In our laboratory, we have applied supercritical fluid namely CO2, as a medium for pharmaceutical processing and also for heterogeneous catalysis. The method used for pharmaceutical processing is based on the Rapid Expansion of supercritical solutions into a liquid SOLVent (RESOLV). We have used this method for the preparation of nanoparticles from various anti-inflammatory (Ibuprofen and Naproxen), anti-fungal (Amphotericin B) and anti-cancer (Paclitaxel) drugs. The anticancer drug nanoparticle formulations were further used for in vitro biological evaluation. In this dissertation, results from the preparation, characterization and biological evaluation of nanoscale drug particles are reported. The effect of experimental conditions on the properties of the nanoparticles prepared via our RESOLV method is discussed. In addition we have used supercritical CO2 as a medium for photoreduction of CO2 using dispersed TiO 2 or metal coated-TiO2 nanoparticles encapsulated in nanoscale cavities of perfluorinated ionomer membranes. These catalytic films are also stable chemically and photochemically, reusable in repeated reactions. The results from the characterization of the nanoparticles and the use of films using different catalysts are presented and discussed.

  1. Enhanced Sampling and Analysis, Selection of Technology for Testing

    Energy Technology Data Exchange (ETDEWEB)

    Svoboda, John; Meikrantz, David

    2010-02-01

    The focus of this study includes the investigation of sampling technologies used in industry and their potential application to nuclear fuel processing. The goal is to identify innovative sampling methods using state of the art techniques that could evolve into the next generation sampling and analysis system for metallic elements. This report details the progress made in the first half of FY 2010 and includes a further consideration of the research focus and goals for this year. Our sampling options and focus for the next generation sampling method are presented along with the criteria used for choosing our path forward. We have decided to pursue the option of evaluating the feasibility of microcapillary based chips to remotely collect, transfer, track and supply microliters of sample solutions to analytical equipment in support of aqueous processes for used nuclear fuel cycles. Microchip vendors have been screened and a choice made for the development of a suitable microchip design followed by production of samples for evaluation by ANL, LANL, and INL on an independent basis.

  2. Enhancement technology improves palatability of normal and callipyge lambs.

    Science.gov (United States)

    Everts, A K R; Wulf, D M; Wheeler, T L; Everts, A J; Weaver, A D; Daniel, J A

    2010-12-01

    The objective of this research was to determine if BPI Processing Technology (BPT) improved palatability of normal (NN) and callipyge (CN) lamb meat and to determine the mechanism by which palatability was improved. Ten ewe and 10 wether lambs of each phenotype were slaughtered, and carcass traits were assessed by a trained evaluator. The LM was removed at 2 d postmortem. Alternating sides served as controls (CON) or were treated with BPT. Muscles designated BPT were injected to a target 120% by weight with a patented solution containing water, ammonium hydroxide, carbon monoxide, and salt. Muscle pH, cooking loss, Warner-Bratzler shear force (WBS), sarcomere length, cooked moisture retention, and desmin degradation were measured. A trained sensory panel and a take-home consumer panel evaluated LM chops. Callipyge had a heavier BW and HCW, less adjusted fat thickness, reduced yield grades, and greater conformation scores than NN (P retention, smaller WBS values, greater juiciness ratings, less off-flavors, and greater consumer ratings for raw characteristics (like of portion size, like of color, overall like of appearance) and eating characteristics (like of juiciness, like of flavor) than CON (P retention, improving consumer acceptability of CN to near-normal levels.

  3. Genetic technologies to enhance the Sterile Insect Technique (SIT)

    Energy Technology Data Exchange (ETDEWEB)

    Alphey, Luke; Baker, Pam; Condon, George C.; Condon, Kirsty C.; Dafa' alla, Tarig H.; Fu, Guoliang; Jin, Li; Labbe, Genevieve; Morrison, Neil M.; Nimmo, Derric D.; O' Connell, Sinead; Phillips, Caroline E.; Plackett, Andrew; Scaife, Sarah; Woods, Alexander, E-mail: luke.alphey@zoo.ox.ac.u [Oxitec Ltd., Oxford (United Kingdom); Burton, Rosemary S.; Epton, Matthew J.; Gong, Peng [University of Oxford (United Kingdom). Dept. of Zoology

    2006-07-01

    The Sterile Insect Technique (SIT) has been used very successfully against range of pest insects, including various tephritid fruit flies, several moths and a small number of livestock pests. However, modern genetics could potentially provide several improvements that would increase the cost-effectiveness of SIT, and extend the range of suitable species. These include improved identification of released individuals by incorporation of a stable, heritable, genetic marker; built-in sex separation (genetic sexing); reduction of the hazard posed by non-irradiated accidental releases from mass-rearing facility (fail-safe); elimination of the need for sterilization by irradiation (genetic sterilization). We discuss applications of these methods and the state of the art, at the time of this meeting, in developing suitable strains. We have demonstrated, in several key pest species, that the required strains can be constructed by introducing a repressible dominant lethal genetic system, a method known as RIDL(trade mark). Based on field experience with Medfly, incorporation of a genetic sexing system into SIT programs for other tephritids could potentially provide a very significant improvement in cost-effectiveness. We have now been able to make efficient female-lethal strains for Medfly. One advantage of our approach is that it should be possible rapidly to extend this technology to other fruit fly species; indeed we have recently been able also to make genetic sexing strains of Medfly (Anastrepha ludens). (author)

  4. Liquid-Metal Pump Technologies for Nuclear Surface Power

    Science.gov (United States)

    Polzin, K. A.

    2007-01-01

    Multiple liquid-metal pump options are reviewed for the purpose of determining the technologies that are best suited for inclusion in a nuclear reactor thermal simulator intended to test prototypical space nuclear system components. Conduction, induction, and thermoelectric electromagnetic pumps are evaluated based on their performance characteristics and the technical issues associated with incorporation into a reactor system. The thermoelectric pump is recommended for inclusion in the planned system at NASA MSFC based on its relative simplicity, low power supply mass penalty, flight heritage, and the promise of increased pump efficiency over earlier flight pump designs through the use of skutterudite thermoelectric elements.

  5. Enhancing osseointegration of orthopedic implants with titania nanotube surfaces

    Science.gov (United States)

    Baker, Erin A.

    Introduction: As joint arthroplasty surgical procedures increase annually, the development of new strategies, including novel materials and surface modifications, to attain solid bone-implant fixation are needed to increase implant terms of service. In this study, we evaluate two morphologies of titania nanotubes in both in vitro and in vivo experiments to quantify osseointegrative potential and material-level biocompatibility. Materials and Methods: Samples were prepared via an electrochemical etching process. Two different titania nanotube (TiNT) morphologies were produced, Aligned and Trabecular. For the in vitro experiment, Sprague Dawley (SD) rat marrow-derived bone marrow cells (BMC) were seeded on samples. Alkaline phosphatase (ALP) activity, osteocalcin (OC) expression, expression of relevant genes as well as cell attachment and morphology were assessed. In the first in vivo experiment, Kirschner wires were implanted unilaterally into SD rat femora with a TiNT-etched or unmodified (Control) implant. General health assessments and weekly body weights were recorded. At a 12-week endpoint, hematologic, systemic metal ion, and histologic analyses were performed. For the second in vivo experiment, Kirschner wires were implanted bilaterally into SD rat femora, with a TiNT-etched implant in one femora and unmodified (Control) implant as an internal control. At 4- and 12-week endpoints, femora were assessed via biomechanics, undecalcified histology, micro-computed tomography (muCT), and backscattered electron imaging (BEI) to characterize de novo bone formation. Results: In vitro experiments demonstrated BMC attachment and differentiation into osteoblasts as well as greater ALP activity, OC expression, total cell counts, and gene expression (of Col1a1, IGF-1, and osteonectin) on TiNT surfaces versus Controls. Cells on TiNT-etched substrates were smaller in diameter and more eccentric than Controls. In the first in vivo experiment, there were significant differences

  6. A mixed methods study of foreign language teachers implementing technology-enhanced multimedia instructio

    Directory of Open Access Journals (Sweden)

    Olha Ketsman

    2014-08-01

    Full Text Available Technology-enhanced multimedia instruction offers benefits for foreign language learners. Despite having much potential, technology itself is neither effective or nor effective, but teachers play a key role in determining its effectiveness because they are in charge of making instructional decisions and choose whether and how to use technology. This article fills a gap in the literature by reporting findings of a mixed methods study of technology- enhanced multimedia instruction in middle and high school foreign language classrooms. Convergent parallel mixed methods design was applied in this study and data was collected through quantitative survey and qualitative semi-structured interviews with teachers. Results from the study indicated a significant positive correlation between variables that contribute to the use of technology-enhanced multimedia instruction in foreign language classrooms and described effective technology-enhanced multimedia practices. The findings of the study have implications for teachers, administrators and faculty of teacher preparation programs as well as state teacher education policy makers.

  7. Critical thinking instruction and technology enhanced learning from the student perspective: A mixed methods research study.

    Science.gov (United States)

    Swart, Ruth

    2017-03-01

    Critical thinking is acclaimed as a valuable asset for graduates from higher education programs. Technology has advanced in quantity and quality; recognized as a requirement of 21st century learners. A mixed methods research study was undertaken, examining undergraduate nursing student engagement with critical thinking instruction, platformed on two technology-enhanced learning environments: a classroom response system face-to-face in-class and an online discussion forum out-of-class. The Community of Inquiry framed the study capturing constructivist collaborative inquiry to support learning, and facilitate critical thinking capability. Inclusion of quantitative and qualitative data sources aimed to gather a comprehensive understanding of students' development of critical thinking and engagement with technology-enhanced learning. The findings from the students' perspectives were positive toward the inclusion of technology-enhanced learning, and use in supporting their development of critical thinking. Students considered the use of two forms of technology beneficial in meeting different needs and preferences, offering varied means to actively participate in learning. They valued critical thinking instruction being intentionally aligned with subject-specific content facilitating understanding, application, and relevance of course material. While the findings are limited to student participants, the instructional strategies and technology-enhanced learning identified as beneficial can inform course design for the development of critical thinking. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. In vitro selection technologies to enhance biomaterial functionality.

    Science.gov (United States)

    Rosch, Jonah C; Hollmann, Emma K; Lippmann, Ethan S

    2016-05-01

    Cells make decisions and fate choices based in part on cues they receive from their external environment. Factors that affect the interpretation of these cues include the soluble proteins that are present at any given time, the cell surface receptors that are available to bind these proteins, and the relative affinities of the soluble proteins for their cognate receptors. Researchers have identified many of the biological motifs responsible for the high-affinity interactions between proteins and their receptors, and subsequently incorporated these motifs into biomaterials to elicit control over cell behavior. Common modes of control include localized sequestration of proteins to improve bioavailability and direct inhibition or activation of a receptor by an immobilized peptide or protein. However, naturally occurring biological motifs often possess promiscuous affinity for multiple proteins and receptors or lack programmable actuation in response to dynamic stimuli, thereby limiting the amount of control they can exert over cellular decisions. These natural motifs only represent a small fraction of the biological diversity that can be assayed by in vitro selection strategies, and the discovery of "artificial" motifs with varying affinity, specificity, and functionality could greatly expand the repertoire of engineered biomaterial properties. This minireview provides a brief summary of classical and emerging techniques in peptide phage display and nucleic acid aptamer selections and discusses prospective applications in the areas of cell adhesion, angiogenesis, neural regeneration, and immune modulation. © 2016 by the Society for Experimental Biology and Medicine.

  9. Cell Surface and Membrane Engineering: Emerging Technologies and Applications.

    Science.gov (United States)

    Saeui, Christopher T; Mathew, Mohit P; Liu, Lingshui; Urias, Esteban; Yarema, Kevin J

    2015-06-18

    Membranes constitute the interface between the basic unit of life-a single cell-and the outside environment and thus in many ways comprise the ultimate "functional biomaterial". To perform the many and often conflicting functions required in this role, for example to partition intracellular contents from the outside environment while maintaining rapid intake of nutrients and efflux of waste products, biological membranes have evolved tremendous complexity and versatility. This article describes how membranes, mainly in the context of living cells, are increasingly being manipulated for practical purposes with drug discovery, biofuels, and biosensors providing specific, illustrative examples. Attention is also given to biology-inspired, but completely synthetic, membrane-based technologies that are being enabled by emerging methods such as bio-3D printers. The diverse set of applications covered in this article are intended to illustrate how these versatile technologies-as they rapidly mature-hold tremendous promise to benefit human health in numerous ways ranging from the development of new medicines to sensitive and cost-effective environmental monitoring for pathogens and pollutants to replacing hydrocarbon-based fossil fuels.

  10. Enhancement of the Laser Transmission Weldability between Polyethylene and Polyoxymethylene by Plasma Surface Treatment.

    Science.gov (United States)

    Liu, Huixia; Jiang, Yingjie; Tan, Wensheng; Wang, Xiao

    2017-12-26

    Due to their large compatibility difference, polyethylene (PE) and polyoxymethylene (POM) cannot be welded together by laser transmission welding. In this study, PE and POM are pretreated using plasma that significantly enhances their laser transmission welding strength. To understand the mechanism underlying the laser welding strength enhancement, surface modification is analyzed using contact angle measurements, atomic force microscopy (AFM), optical microscopy, and X-ray photoelectron spectroscopy (XPS). Characterization results show that the plasma surface treatment improves the surface free energy, significantly enhancing the wettability of the materials. The increase in surface roughness and the generation of homogeneous bubbles contribute to the formation of mechanical micro-interlocking. The oxygen-containing groups introduced by the oxygen plasma treatment improve the compatibility of PE and POM, and facilitate the diffusion and entanglement of molecular chains and the formation of van der Waals force.

  11. Enhancement of the Laser Transmission Weldability between Polyethylene and Polyoxymethylene by Plasma Surface Treatment

    Directory of Open Access Journals (Sweden)

    Huixia Liu

    2017-12-01

    Full Text Available Due to their large compatibility difference, polyethylene (PE and polyoxymethylene (POM cannot be welded together by laser transmission welding. In this study, PE and POM are pretreated using plasma that significantly enhances their laser transmission welding strength. To understand the mechanism underlying the laser welding strength enhancement, surface modification is analyzed using contact angle measurements, atomic force microscopy (AFM, optical microscopy, and X-ray photoelectron spectroscopy (XPS. Characterization results show that the plasma surface treatment improves the surface free energy, significantly enhancing the wettability of the materials. The increase in surface roughness and the generation of homogeneous bubbles contribute to the formation of mechanical micro-interlocking. The oxygen-containing groups introduced by the oxygen plasma treatment improve the compatibility of PE and POM, and facilitate the diffusion and entanglement of molecular chains and the formation of van der Waals force.

  12. Enhancement of Visible-Luminescence Saturation Intensity by Surface Plasmons in Ag /ZnO Films

    Science.gov (United States)

    Nakamura, Toshihiro

    2016-10-01

    We systematically investigate visible defect-related photoluminescence (PL) properties of ZnO films with Ag nanostructures by changing the size of Ag and the power densities of excitation-laser light. We find that the PL intensity and the recombination rate are enhanced and peak at a particular size of a Ag nanostructure where its surface-plasmon resonance corresponds to the defect-emission band. The enhancements are due to the excitation of surface plasmons in Ag nanostructures and resultant local-field enhancement in the recombination energy of the defect-emission band. Furthermore, the saturation intensity of the defect-related emission in the higher-excitation power-density regime (>approximately 10 MW /cm2 ) is found to be strongly enhanced in the presence of Ag nanostructures, and the enhancement degree depends on the size of the nanostructures. The enhanced saturation behavior in the excitation power dependence of the emission intensity is well reproduced by the theoretical calculation based on a simple rate-equation model considering the surface-plasmon-induced enhancement of the radiative recombination rate. This result indicates that the saturation-intensity enhancement originates from the inhibition of the filling effect of defect states with excited carriers via plasmon-induced modification of their radiative processes.

  13. Feasibility of Single Molecule DNA Sequencing using Surface-Enhanced Raman Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Talley, C E; Reboredo, F; Chan, J; Lane, S M

    2006-02-03

    We have used a combined theoretical and experimental approach in order to assess the feasibility of using surface-enhanced Raman scattering (SERS) for DNA sequencing at the single molecule level. We have developed a numerical tool capable of calculating the E-field and resulting SERS enhancement factors for metallic structures of arbitrary size and shape. Measurements of the additional SERS enhancement by combining SERS with coherent antistokes Raman scattering (CARS) show that only modest increases in the signal are achievable due to thermal damage at higher laser powers. Finally, measurements of the SERS enhancement from nanoparticles coated with an insulating layer show that the SERS enhancement is decreased by as much as two orders of magnitude when the molecule is not in contact with the metal surface.

  14. Immunoassay using probe-labelling immunogold nanoparticles with silver staining enhancement via surface-enhanced Raman scattering.

    Science.gov (United States)

    Xu, Shuping; Ji, Xiaohui; Xu, Weiqing; Li, Xiaoling; Wang, Lianying; Bai, Yubai; Zhao, Bing; Ozaki, Yukihiro

    2004-01-01

    This paper reports a novel immunoassay based on surface-enhanced Raman scattering (SERS) and immunogold labelling with silver staining enhancement. Immunoreactions between immunogold colloids modified by a Raman-active probe molecule (e.g., 4-mercaptobenzoic acid) and antigens, which were captured by antibody-assembled chips such as silicon or quartz, were detected via SERS signals of Raman-active probe molecule. All the self-assembled steps were subjected to the measurements of ultraviolet-visible (UV-vis) spectra to monitor the formation of a sandwich structure onto a substrate. The immunoassay was performed by a sandwich structure consisting of three layers. The first layer was composed of immobilized antibody molecules of mouse polyclonal antibody against Hepatitis B virus surface antigen (PAb) on a silicon or quartz substrate. The second layer was the complementary Hepatitis B virus surface antigen (Antigen) molecules captured by PAb on the substrate. The third layer was composed of the probe-labelling immunogold nanoparticles, which were modified by mouse monoclonal antibody against Hepatitis B virus surface antigen (MAb) and 4-mercaptobenzoic acid (MBA) as the Raman-active probe on the surface of gold colloids. After silver staining enhancement, the antigen is identified by a SERS spectrum of MBA. A working curve of the intensity of a SERS signal at 1585 cm(-1) due to the [small nu](8a) aromatic ring vibration of MBA versus the concentration of analyte (Antigen) was obtained and the non-optimized detection limit for the Hepatitis B virus surface antigen was found to be as low as 0.5 [micro sign]g mL(-1).

  15. Enhanced AFCI Sampling, Analysis, and Safeguards Technology Review

    Energy Technology Data Exchange (ETDEWEB)

    John Svoboda

    2009-09-01

    The focus of this study includes the investigation of sampling technologies used in industry and their potential application to nuclear fuel processing. The goal is to identify innovative sampling methods using state of the art techniques that could evolve into the next generation sampling and analysis system for metallic elements. Sampling and analysis of nuclear fuel recycling plant processes is required both to monitor the operations and ensure Safeguards and Security goals are met. In addition, environmental regulations lead to additional samples and analysis to meet licensing requirements. The volume of samples taken by conventional means, can restrain productivity while results samples are analyzed, require process holding tanks that are sized to meet analytical issues rather than process issues (and that create a larger facility footprint), or, in some cases, simply overwhelm analytical laboratory capabilities. These issues only grow when process flowsheets propose new separations systems and new byproduct material for transmutation purposes. Novel means of streamlining both sampling and analysis are being evaluated to increase the efficiency while meeting all requirements for information. This report addresses just a part of the effort to develop and study novel methods by focusing on the sampling and analysis of aqueous samples for metallic elements. It presents an overview of the sampling requirements, including frequency, sensitivity, accuracy, and programmatic drivers, to demonstrate the magnitude of the task. The sampling and analysis system needed for metallic element measurements is then discussed, and novel options being applied to other industrial analytical needs are presented. Inductively coupled mass spectrometry instruments are the most versatile for metallic element analyses and are thus chosen as the focus for the study. Candidate novel means of process sampling, as well as modifications that are necessary to couple such instruments to

  16. Surface Functionalization for Enhanced Fluorescence Detection, Surface Plasmon Resonance Imaging and Microscopy

    OpenAIRE

    Fasoli, Jennifer Betsy

    2015-01-01

    This work presents several high throughput imaging and analysis techniques performed by fluorescence detection and surface plasmon resonance biosensing. The microarray fabrication methods introduced in this thesis, as well as the DNA functionalization on planar and nanoparticle surfaces, enable and facilitate the real-time study of adsorption events via DNA- DNA hybridization and protein-DNA interaction. Silica deposited on polyolefin film serves as the base for the development of DNA mic...

  17. Development of surface enhanced Raman scattering (SERS) spectroscopy monitoring of fuel markers to prevent fraud

    Science.gov (United States)

    Wilkinson, Timothy; Clarkson, John; White, Peter C.; Meakin, Nicholas; McDonald, Ken

    2013-05-01

    Governments often tax fuel products to generate revenues to support and stimulate their economies. They also subsidize the cost of essential fuel products. Fuel taxation and subsidization practices are both subject to fraud. Oil marketing companies also suffer from fuel fraud with loss of legitimate sales and additional quality and liability issues. The use of an advanced marking system to identify and control fraud has been shown to be effective in controlling illegal activity. DeCipher has developed surface enhanced Raman scattering (SERS) spectroscopy as its lead technology for measuring markers in fuel to identify and control malpractice. SERS has many advantages that make it highly suitable for this purpose. The SERS instruments are portable and can be used to monitor fuel at any point in the supply chain. SERS shows high specificity for the marker, with no false positives. Multiple markers can also be detected in a single SERS analysis allowing, for example, specific regional monitoring of fuel. The SERS analysis from fuel is also quick, clear and decisive, with a measurement time of less than 5 minutes. We will present results highlighting our development of the use of a highly stable silver colloid as a SERS substrate to measure the markers at ppb levels. Preliminary results from the use of a solid state SERS substrate to measure fuel markers will also be presented.

  18. Fast quantitative detection of thiram using surface-enhanced Raman scattering and support vector machine regression

    Science.gov (United States)

    Weng, Shizhuang; Yuan, Baohong; Zhu, Zede; Huang, Linsheng; Zhang, Dongyan; Zheng, Ling

    2016-03-01

    As a novel and ultrasensitive detection technology that had advantages of fingerprint effect, high speed and low cost, surface-enhanced Raman scattering (SERS) was used to develop the regression models for the fast quantitative detection of thiram by support vector machine regression (SVR) in the paper. Meanwhile, three parameter optimization methods, which were grid search (GS), genetic algorithm (GA) and particle swarm optimization (PSO), were employed to optimize the internal parameters of SVR. Furthermore, the influence of the spectral number, spectral wavenumber range and principal component analysis (PCA) on the quantitative detection was also discussed. Firstly, the experiments demonstrate the proposed method can realize the fast and quantitative detection of thiram, and the best result is obtained by GS-SVR with the spectra of the range of characteristic peak which are processed by PCA. And the effect of GS, GA, PSO on the parameter optimization is similar, but the analysis time has a great difference in which GS is the fastest. Considering the analysis accuracy and time simultaneously, the spectral number of samples over each concentration should be set to 50. Then, developing the quantitative model with the spectra of range of characteristic peak can reduce analysis time on the promise of ensuring the detection accuracy. Additionally, PCA can further reduce the detection error through reserving the main information of the spectra data and eliminating the noise.

  19. Functional properties of bio-inspired surfaces: characterization and technological applications

    National Research Council Canada - National Science Library

    Favret, Eduardo A; Fuentes, Néstor O

    2009-01-01

    ... to functional technological materials. It analyses how such surfaces can be described and characterized using microscopic techniques and thus reproduced, encompassing the important areas of current surface replication techniques and the associated acquisition of good master structures. It is well known that biological systems have the ability to sense, ...

  20. Frictional and bone ingrowth properties of engineered surface topographies produced by electron beam technology

    NARCIS (Netherlands)

    Biemond, J. Elizabeth; Aquarius, Rene; Verdonschot, Nicolaas Jacobus Joseph; Buma, Pieter

    2011-01-01

    Background Electron beam melting (E-beam) is a new technology to produce 3-dimensional surface topographies for cementless orthopedic implants. Methods The friction coefficients of two newly developed E-beam produced surface topographies were in vitro compared with sandblasted E-beam and titanium

  1. Functional properties of bio-inspired surfaces: characterization and technological applications

    National Research Council Canada - National Science Library

    Favret, Eduardo A; Fuentes, Néstor O

    2009-01-01

    ... technological materials. It analyses how such surfaces can be described and characterized using microscopic techniques and thus reproduced, encompassing the important areas of current surface replication techniques and the associated acquisition of good master structures. It is well known that biological systems have the ability to sense, ...

  2. Science Teaching Orientations and Technology-Enhanced Tools for Student Learning

    Science.gov (United States)

    Campbell, Todd; Longhurst, Max; Duffy, Aaron M.; Wolf, Paul G.; Shelton, Brett E.

    2013-01-01

    This qualitative study examines teacher orientations and technology-enhanced tools for student learning within a science literacy framework. Data for this study came from a group of 10 eighth grade science teachers. Each of these teachers was a participant in a professional development (PD) project focused on reformed and technology-enhanced science instruction shaped by national standards documents. The research is focused on identifying teacher orientations and use of technology-enhanced tools prior to or unaffected by PD. The primary data sources for this study are drawn from learning journals and classroom observations. Qualitative methods were used to analyze learning journals, while descriptive statistics were used from classroom observations to further explore and triangulate the emergent qualitative findings. Two teacher orientation teacher profiles were developed to reveal the emergent teacher orientation dimensions and technology-enhanced tool categories found: "more traditional teacher orientation profile" and "toward a reformed-based teacher orientation profile." Both profiles were founded on "knowledge of" beliefs about the goals and purposes for science education, while neither profile revealed sophisticated beliefs about the nature of science. The "traditional" profile revealed more teacher-centered beliefs about science teaching and learning, and the "towards reformed-based" profile revealed student-centered beliefs. Finally, only technology-enhanced tools supportive of collaborative construction of science knowledge were found connected to the "towards reformed-based" profile. This research is concluded with a proposed "reformed-based teacher orientation profile" as a future target for science teaching and learning with technology-enhanced tools in a science literacy framework.

  3. The use of surface-enhanced Raman scattering for detecting molecular evidence of life in rocks, sediments, and sedimentary deposits.

    Science.gov (United States)

    Bowden, Stephen A; Wilson, Rab; Cooper, Jonathan M; Parnell, John

    2010-01-01

    Raman spectroscopy is a versatile analytical technique capable of characterizing the composition of both inorganic and organic materials. Consequently, it is frequently suggested as a payload on many planetary landers. Only approximately 1 in every 10(6) photons are Raman scattered; therefore, the detection of trace quantities of an analyte dispersed in a sample matrix can be much harder to achieve. To overcome this, surface-enhanced Raman scattering (SERS) and surface-enhanced resonance Raman scattering (SERRS) both provide greatly enhanced signals (enhancements between 10(5) and 10(9)) through the analyte's interaction with the locally generated surface plasmons, which occur at a "roughened" or nanostructured metallic surface (e.g., Cu, Au, and Ag). Both SERS and SERRS may therefore provide a viable technique for trace analysis of samples. In this paper, we describe the development of SERS assays for analyzing trace amounts of compounds present in the solvent extracts of sedimentary deposits. These assays were used to detect biological pigments present in an Arctic microoasis (a small locale of elevated biological productivity) and its detrital regolith, characterize the pigmentation of microbial mats around hydrothermal springs, and detect fossil organic matter in hydrothermal deposits. These field study examples demonstrate that SERS technology is sufficiently mature to be applied to many astrobiological analog studies on Earth. Many current and proposed imaging systems intended for remote deployment already posses the instrumental components needed for SERS. The addition of wet chemistry sample processing facilities to these instruments could yield field-deployable analytical instruments with a broadened analytical window for detecting organic compounds with a biological or geological origin.

  4. Surface tailored organobentonite enhances bacterial proliferation and phenanthrene biodegradation under cadmium co-contamination

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Asit [Future Industries Institute (formerly Centre for Environmental Risk Assessment and Remediation), University of South Australia, Mawson Lakes, SA 5095 (Australia); Indian Council of Agricultural Research (ICAR), Indian Institute of Soil Science, Bhopal (India); Biswas, Bhabananda [Future Industries Institute (formerly Centre for Environmental Risk Assessment and Remediation), University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), ACT Building, University of Newcastle, Callaghan, NSW 2308 (Australia); Sarkar, Binoy, E-mail: binoy.sarkar@unisa.edu.au [Future Industries Institute (formerly Centre for Environmental Risk Assessment and Remediation), University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), ACT Building, University of Newcastle, Callaghan, NSW 2308 (Australia); Patra, Ashok K. [Indian Council of Agricultural Research (ICAR), Indian Institute of Soil Science, Bhopal (India); Naidu, Ravi, E-mail: ravi.naidu@newcastle.edu.au [Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), ACT Building, University of Newcastle, Callaghan, NSW 2308 (Australia); Global Centre for Environmental Remediation (GCER), Faculty of Science and Information Technology, University of Newcastle, Callaghan, NSW 2308 (Australia)

    2016-04-15

    Co-contamination of soil and water with polycyclic aromatic hydrocarbon (PAH) and heavy metals makes biodegradation of the former extremely challenging. Modified clay-modulated microbial degradation provides a novel insight in addressing this issue. This study was conducted to evaluate the growth and phenanthrene degradation performance of Mycobacterium gilvum VF1 in the presence of a palmitic acid (PA)-grafted Arquad® 2HT-75-based organobentonite in cadmium (Cd)-phenanthrene co-contaminated water. The PA-grafted organobentonite (ABP) adsorbed a slightly greater quantity of Cd than bentonite at up to 30 mg L{sup −1} metal concentration, but its highly negative surface charge imparted by carboxylic groups indicated the potential of being a significantly superior adsorbent of Cd at higher metal concentrations. In systems co-contained with Cd (5 and 10 mg L{sup −1}), the Arquad® 2HT-75-modified bentonite (AB) and PA-grafted organobentonite (ABP) resulted in a significantly higher (72–78%) degradation of phenanthrene than bentonite (62%) by the bacterium. The growth and proliferation of bacteria were supported by ABP which not only eliminated Cd toxicity through adsorption but also created a congenial microenvironment for bacterial survival. The macromolecules produced during ABP–bacteria interaction could form a stable clay-bacterial cluster by overcoming the electrostatic repulsion among individual components. Findings of this study provide new insights for designing clay modulated PAH bioremediation technologies in mixed-contaminated water and soil. - Highlights: • Surface tailored organobentonite synthesised and characterised • Modified clay adsorbs Cd and reduces toxicity to Mycobacterium gilvum. • It creates congenial microenvironment for bacterial survival. • It enhances phenanthrene biodegradation in metal co-contaminated condition.

  5. Technology-Enhanced Formative Assessment: A Research-Based Pedagogy for Teaching Science with Classroom Response Technology

    Science.gov (United States)

    Beatty, Ian D.; Gerace, William J.

    2009-04-01

    Classroom response systems (CRSs) are a promising instructional technology, but most literature on CRS use fails to distinguish between technology and pedagogy, to define and justify a pedagogical perspective, or to discriminate between pedagogies. Technology-enhanced formative assessment (TEFA) is our pedagogy for CRS-based science instruction, informed by experience and by several traditions of educational research. In TEFA, four principles enjoin the practice of question-driven instruction, dialogical discourse, formative assessment, and meta-level communication. These are enacted via the question cycle, an iterative pattern of CRS-based questioning that can serve multiple instructional needs. TEFA should improve CRS use and help teachers "bridge the gap" between educational research findings and practical, flexible classroom strategies for science instruction.

  6. Evaluation Of Electrochemical Machining Technology For Surface Improvements In Additive Manufactured Components

    Energy Technology Data Exchange (ETDEWEB)

    Dehoff, Ryan R [ORNL; List III, Frederick Alyious [ORNL; Carver, Keith [ORNL

    2015-09-23

    ORNL Manufacturing Demonstration Facility worked with ECM Technologies LLC to investigate the use of precision electro-chemical machining technology to polish the surface of parts created by Arcam electron beam melting. The goals for phase one of this project have been met. The project goal was to determine whether electro-chemical machining is a viable method to improve the surface finish of Inconel 718 parts fabricated using the Arcam EBM method. The project partner (ECM) demonstrated viability for parts of both simple and complex geometry. During the course of the project, detailed process knowledge was generated. This project has resulted in the expansion of United States operations for ECM Technologies.

  7. Surface plasmon-enhanced and quenched two-photon excited fluorescence

    Science.gov (United States)

    Lin, C.-Y.; Lien, C.-H.; Chiu, K.-C.; Chang, C.-Y.; Chang, S.-H.; Guo, T.-F.; Chen, S.-J.

    2010-08-01

    This study investigated theoretically and experimentally that two-photon excited fluorescence is enhanced and quenched via surface plasmons (SPs) excited by total internal reflection with a silver film. The fluorescence intensity is fundamentally affected by the local electromagnetic field enhancement and the quantum yield change according to the surrounding structure and materials. By utilizing the Fresnel equation and classical dipole radiation modeling, local electric field enhancement, fluorescence quantum yield, and fluorescence emission coupling yield via SPs were theoretically analyzed at different dielectric spacer thicknesses between the fluorescence dye and the metal film. The fluorescence lifetime was also decreased substantially via the quenching effect. A two-photon excited total internal reflection fluorescence (TIRF) microscopy with a time-correlated single photon counting device has been developed to measure the fluorescence lifetimes, photostabilities, and enhancements. The experimental results demonstrate that the fluorescence lifetimes and the trend of the enhancements are consistent with the theoretical analysis. The maximum fluorescence enhancement factor in the surface plasmon-total internal reflection fluorescence (SP-TIRF) configuration can be increased up to 30 fold with a suitable thickness SiO2 spacer. Also, to compromise for the fluorescence enhancement and the fluorophore photostability, we find that the SP-TIRF configuration with a 10 nm SiO2 spacer can provide an enhanced and less photobleached fluorescent signal via the assistance of enhanced local electromagnetic field and quenched fluorescence lifetime, respectively.

  8. Surface-enhanced Raman scattering from AgNP-graphene-AgNP sandwiched nanostructures

    Science.gov (United States)

    Wu, Jian; Xu, Yijun; Xu, Pengyu; Pan, Zhenghui; Chen, Sheng; Shen, Qishen; Zhan, Li; Zhang, Yuegang; Ni, Weihai

    2015-10-01

    We developed a facile approach toward hybrid AgNP-graphene-AgNP sandwiched structures using self-organized monolayered AgNPs from wet chemical synthesis for the optimized enhancement of the Raman response of monolayer graphene. We demonstrate that the Raman scattering of graphene can be enhanced 530 fold in the hybrid structure. The Raman enhancement is sensitively dependent on the hybrid structure, incident angle, and excitation wavelength. A systematic simulation is performed, which well explains the enhancement mechanism. Our study indicates that the enhancement resulted from the plasmonic coupling between the AgNPs on the opposite sides of graphene. Our approach towards ideal substrates offers great potential to produce a ``hot surface'' for enhancing the Raman response of two-dimensional materials.We developed a facile approach toward hybrid AgNP-graphene-AgNP sandwiched structures using self-organized monolayered AgNPs from wet chemical synthesis for the optimized enhancement of the Raman response of monolayer graphene. We demonstrate that the Raman scattering of graphene can be enhanced 530 fold in the hybrid structure. The Raman enhancement is sensitively dependent on the hybrid structure, incident angle, and excitation wavelength. A systematic simulation is performed, which well explains the enhancement mechanism. Our study indicates that the enhancement resulted from the plasmonic coupling between the AgNPs on the opposite sides of graphene. Our approach towards ideal substrates offers great potential to produce a ``hot surface'' for enhancing the Raman response of two-dimensional materials. Electronic supplementary information (ESI) available: Additional SEM images, electric field enhancement profiles, Raman scattering spectra, and structure-dependent peak ratios. See DOI: 10.1039/c5nr04500b

  9. Enhancing the antibacterial performance of orthopaedic implant materials by fibre laser surface engineering

    DEFF Research Database (Denmark)

    Chan, Chi-Wai; Carson, Louise; Smith, Graham C.

    2017-01-01

    to the effort on enhancing osseointegration, wear and corrosion resistance of implant materials. In this study, the effects of laser surface treatment on enhancing the antibacterial properties of commercially pure (CP) Ti (Grade 2), Ti6Al4V (Grade 5) and CoCrMo alloy implant materials were studied and compared...... for the first time. Laser surface treatment was performed by a continuous wave (CW) fibre laser with a near-infrared wavelength of 1064 nm in a nitrogen-containing environment. Staphylococcus aureus, commonly implicated in infection associated with orthopaedic implants, was used to investigate the antibacterial...... properties of the laser-treated surfaces. The surface roughness and topography of the laser-treated materials were analysed by a 2D roughness testing and by AFM. The surface morphologies before and after 24 h of bacterial cell culture were captured by SEM, and bacterial viability was determined using live...

  10. Inquiry-Based Science and Technology Enrichment Program: Green Earth Enhanced with Inquiry and Technology

    Science.gov (United States)

    Kim, Hanna

    2011-01-01

    This study investigated the effectiveness of a guided inquiry integrated with technology, in terms of female middle-school students' attitudes toward science/scientists and content knowledge regarding selective science concepts (e.g., Greenhouse Effect, Air/Water Quality, Alternative Energy, and Human Health). Thirty-five female students who were…

  11. Spray Cooling Trajectory Angle Impact Upon Heat Flux Using a Straight Finned Enhanced Surface

    Science.gov (United States)

    Silk, Eric A.; Kim, Jungho; Kiger, Ken

    2005-01-01

    Experiments were conducted to study the effects of spray trajectory angles upon heat flux for flat and enhanced surface spray cooling. The surface enhancement consisted of straight fins machined on the top surface of a copper heater block. Spray cooling curves were obtained with the straight fin surface aligned both parallel (axial) and perpendicular (transverse) to the spray axis. Measurements were also obtained on a flat surface heater block for comparison purposes. Each copper block had a cross-sectional area of 2.0 sq cm. A 2x2 nozzle array was used with PF-5060 as the working fluid. Thermal performance data was obtained under nominally degassed (chamber pressure of 41.4 kPa) conditions. Results show that the maximum CHF in all cases was attained for a trajectory angle of 30' from the surface normal. Furthermore, trajectory angles applied to straight finned surfaces can have a critical heat flux (CHF) enhancement as much as 75% (heat flux value of 140 W/sq cm) relative to the vertical spray orientation for the analogous flat surface case under nominally degassed conditions.

  12. [The new technology of enhanced radiofrequency ablation is safe and effective for treating giant hepatic hemangioma].

    Science.gov (United States)

    Zou, Hua; Yan, Jun; Wu, Yan-xia; Ou, Xia; Li, Xiao-wu; Xia, Feng; Ma, Kuan-sheng; Bie, Ping

    2012-04-01

    To determine the safety and efficacy of the enhanced radiofrequency ablation (RFA) new technology for treatment of giant hepatic hemangiomas. From August 2010 to September 2011, 30 patients with giant hepatic hemangiomas (average diameter: 7.7+/-1.9 cm, range: 5.0 to 12.8 cm) were treated with enhanced RFA. The original lesion diameter, enhanced radiofrequency duration, and cases of RFA-induced burning were recorded. Cases requiring a second RFA treatment were also recorded. Correlation analysis was carried out to determine the association of enhanced RFA with adverse events and change in lesion diameter. The rate of completely destroyed lesions by enhanced RFA was 70.96%, and the total rate of reduced lesions was 87.1%. No severe adverse events occurred. The duration of enhanced radiofrequency correlated positively with the original lesion diameter (r=0.687, P less than 0.01). The enhanced RFA treatment significantly reduced the average lesion diameter (follow-up: 6.2+/-1.8 cm; t=6.417, P less than 0.01). The new minimally-invasive technology of enhanced radiofrequency ablation is effective and safe for treating giant hepatic hemangiomas and produces an obvious, short-term curative effect.

  13. Surface enhanced Raman scattering optimization of gold nanocylinder arrays: Influence of the localized surface plasmon resonance and excitation wavelength

    Directory of Open Access Journals (Sweden)

    N. Guillot

    2011-09-01

    Full Text Available We here emphasize that the Surface Enhanced Raman Scattering (SERS intensity has to be optimized by choosing the appropriate gold nanoparticles size for two excitation wavelengths: 632.8 and 785 nm. We discuss the role of the position and of the order of the Localized Surface Plasmon Resonance (LSPR in such optimization for both wavelengths. At 632.8 nm, the best SERS intensity is reached for a LSPR located between the excitation and Raman wavelengths whereas at 785 nm, the LSPR should be placed outside this range. The third order of LSPR is shown to have no influence on the SERS intensity.

  14. Nocturnal surface ozone enhancement over Portugal during winter: Influence of different atmospheric conditions

    KAUST Repository

    Kulkarni, Pavan S.

    2016-09-24

    Four distinct nocturnal surface ozone (NSO) enhancement events were observed, with NSO concentration exceeding 80μg/m3, at multiple ozone (O3) monitoring stations (32 sites) in January, November and December between year 2000–2010, in Portugal. The reasonable explanation for the observed bimodal pattern of surface ozone with enhanced NSO concentration during nighttime has to be transport processes, as the surface ozone production ceases at nighttime. Simultaneous measurements of O3 at multiple stations during the study period in Portugal suggest that horizontal advection alone cannot explain the observed NSO enhancement. Thus, detailed analysis of the atmospheric conditions, simulated with the Weather Research and Forecasting (WRF) model, were performed to evaluate the atmospheric mechanisms responsible for NSO enhancement in the region. Simulations revealed that each event occurred as a result of one or the combination of different atmospheric processes such as, passage of a cold front followed by a subsidence zone; passage of a moving surface trough, with associated strong horizontal wind speed and vertical shear; combination of vertical and horizontal transport at the synoptic scale; formation of a low level jet with associated vertical mixing below the jet stream. The study confirmed that large-scale flow pattern resulting in enhanced vertical mixing in the nocturnal boundary layer, plays a key role in the NSO enhancement events, which frequently occur over Portugal during winter months. © 2016 Elsevier Ltd

  15. Surface-Passivated AlGaN Nanowires for Enhanced Luminescence of Ultraviolet Light Emitting Diodes

    KAUST Repository

    Sun, Haiding

    2017-12-19

    Spontaneously-grown, self-aligned AlGaN nanowire ultraviolet light emitting diodes still suffer from low efficiency partially because of the strong surface recombination caused by surface states, i.e., oxidized surface and high density surface states. Several surface passivation methods have been introduced to reduce surface non-radiative recombination by using complex and toxic chemicals. Here, we present an effective method to suppress such undesirable surface recombination of the AlGaN nanowires via diluted potassium hydroxide (KOH) solution; a commonly used chemical process in semiconductor fabrication which is barely used as surface passivation solution in self-assembled nitride-based nanowires. The transmission electron microscopy investigation on the samples reveals almost intact nanowire structures after the passivation process. We demonstrated an approximately 49.7% enhancement in the ultraviolet light output power after 30-s KOH treatment on AlGaN nanowires grown on titanium-coated silicon substrates. We attribute such a remarkable enhancement to the removal of the surface dangling bonds and oxidized nitrides (Ga-O or Al-O bonds) at the surface as we observe the change of the carrier lifetime before and after the passivation. Thus, our results highlight the possibility of employing this process for the realization of high performance nanowire UV emitters.

  16. INFORMATION TECHNOLOGY FOR ENHANCING NGOS’ PERFORMANCE IN THE KINGDOM OF BAHRAIN

    OpenAIRE

    Jaflah Al-Ammary; Sharifa Hamad

    2012-01-01

    The current research aims to investigate the situation of the NGOs in the Kingdom of Bahrain from many aspects: types of IT adopted, reasons behind adopting IT, obstacles to adopting IT, perception of the impact of adopting IT to enhance organizational performance, and perception of the importance of using the Internet and web-based technology in enhancing NGOs’ organization services. Based on the investigation, a framework for adopting IT by NGOs in the Kingdom of Bahrain was developed. The ...

  17. TECHNOLOGIES TO ENHANCE OPERATION OF THE EXISTING NATURAL GAS COMPRESSION INFRASTRUCTURE

    Energy Technology Data Exchange (ETDEWEB)

    Anthony J. Smalley; Ralph E. Harris; Gary D. Bourn

    2003-10-01

    This report documents work performed in the fourth quarter of the project entitled: ''Technologies to Enhance Operation of the Existing Natural Gas Compression Infrastructure''. The project objective is to develop and substantiate methods for operating integral engine/compressors in gas pipeline service, which reduce fuel consumption, increase capacity, and enhance mechanical integrity. The report describes the following work: second field test; test data analysis for the first field test; operational optimization plans.

  18. TECHNOLOGIES TO ENHANCE OPERATION OF THE EXISTING NATURAL GAS COMPRESSION INFRASTRUCTURE

    Energy Technology Data Exchange (ETDEWEB)

    Anthony J. Smalley; Ralph E. Harris; Gary D. Bourn

    2004-01-01

    This report documents work performed in the fifth quarter of the project entitled: ''Technologies to Enhance Operation of the Existing Natural Gas Compression Infrastructure''. The project objective is to develop and substantiate methods for operating integral engine/compressors in gas pipeline service, which reduce fuel consumption, increase capacity, and enhance mechanical integrity. The report describes the following work: completion of analysis of data from first visit to second site; preparation for follow-up testing.

  19. Developing a Mobile Application via Bluetooth Wireless Technology for Enhancing Communication

    OpenAIRE

    Sahar A. Idwan

    2009-01-01

    This paper presents Mobile application via Bluetooth wireless technology (MAvBT) that enhance the student portal in universities by connecting students' mobile phone devices to a server application that benefit from the devices Bluetooth technology and the storage abilities. MAvBT enables students to retrieve their information with minimum time and anywhere ranging from 100m up to 1Km and it facilitate the communication with instructors outside the office hours. This system consists of comput...

  20. Surface nanotopography of an anodized Ti–6Al–7Nb alloy enhances cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Her-Hsiung [Department of Dentistry, National Yang-Ming University, Taipei 112, Taiwan (China); Graduate Institute of Basic Medical Science, China Medical University, Taichung 404, Taiwan (China); Department of Biomedical Informatics, Asia University, Taichung 413, Taiwan (China); Department of Stomatology, Taipei Veterans General Hospital, Taipei 112, Taiwan (China); Wu, Chia-Ping [Institute of Oral Biology, National Yang-Ming University, Taipei 112, Taiwan (China); Sun, Ying-Sui [Department of Dentistry, National Yang-Ming University, Taipei 112, Taiwan (China); Yang, Wei-En [Institute of Oral Biology, National Yang-Ming University, Taipei 112, Taiwan (China); Lee, Tzu-Hsin, E-mail: biomaterials@hotmail.com [School of Dentistry, Chung Shan Medical University, Taichung 402, Taiwan (China); Oral Medicine Center, Chung Shan Medical University Hospital, Taichung 402, Taiwan (China)

    2014-12-05

    Highlights: • An electrochemical anodization was applied to α/β-type Ti–6Al–7Nb alloy surface. • Anodized surface had a nontoxic nanoporous topography. • Anodized surface increased proteins adsorption due to nanotopography. • Anodized surface enhanced cell growth due to nanotopography. • Electrochemical anodization has potential as implant surface treatment. - Abstract: The α/β-type Ti–6Al–7Nb alloy is a potential replacement for α/β-type Ti–6Al–4V alloy, which is widely used in biomedical implant applications. The biological response to implant material is dependent on the surface characteristics of the material. In the present study, a simple and fast process was developed to perform an electrochemical anodization treatment on Ti–6Al–7Nb alloy. The proposed process yielded a thin surface nanotopography, which enhanced cell growth on the Ti–6Al–7Nb alloy. The surface characteristics, including the morphology, wettability, and protein adsorption, were investigated, and the cytotoxicity was evaluated according to International Organization for Standardization 10993-5 specifications. Cell adhesion of human bone marrow mesenchymal stem cells on the test specimens was observed via fluorescence microscopy and scanning electron microscopy. The anodization process produced a surface nanotopography (pore size <100 nm) on anodized Ti–6Al–7Nb alloy, which enhanced the wettability, protein adsorption, cell adhesion, cell migration, and cell mineralization. The results showed that the surface nanotopography produced using the proposed electrochemical anodization process enhanced cell growth on anodized Ti–6Al–7Nb alloy for implant applications.

  1. Cell Surface and Membrane Engineering: Emerging Technologies and Applications

    Directory of Open Access Journals (Sweden)

    Christopher T. Saeui

    2015-06-01

    Full Text Available Membranes constitute the interface between the basic unit of life—a single cell—and the outside environment and thus in many ways comprise the ultimate “functional biomaterial”. To perform the many and often conflicting functions required in this role, for example to partition intracellular contents from the outside environment while maintaining rapid intake of nutrients and efflux of waste products, biological membranes have evolved tremendous complexity and versatility. This article describes how membranes, mainly in the context of living cells, are increasingly being manipulated for practical purposes with drug discovery, biofuels, and biosensors providing specific, illustrative examples. Attention is also given to biology-inspired, but completely synthetic, membrane-based technologies that are being enabled by emerging methods such as bio-3D printers. The diverse set of applications covered in this article are intended to illustrate how these versatile technologies—as they rapidly mature—hold tremendous promise to benefit human health in numerous ways ranging from the development of new medicines to sensitive and cost-effective environmental monitoring for pathogens and pollutants to replacing hydrocarbon-based fossil fuels.

  2. Photocurrent enhancement by surface plasmon resonance of gold nanoparticles in spray deposited large area dye sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Chander, Nikhil; Singh, Puneet [Photovoltaic Laboratory, Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi 110016 (India); Khan, A.F. [Department of Electronics and Information Technology, Ministry of Communications and Information Technology, Government of India, New Delhi 110003 (India); Dutta, Viresh [Photovoltaic Laboratory, Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi 110016 (India); Komarala, Vamsi K., E-mail: vamsi@ces.iitd.ac.in [Photovoltaic Laboratory, Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi 110016 (India)

    2014-10-01

    A facile method for fabricating large area TiO{sub 2} and TiO{sub 2}–Au nanocomposite films for dye sensitized solar cells (DSSCs) is presented using a spray technique. Pre-synthesized gold nanoparticles (Au NPs) were sprayed together with the TiO{sub 2} NPs and composite films with brilliant coloration due to surface plasmon resonances of Au NPs were prepared. Composite films containing ∼ 15 nm sized Au NPs exhibited enhanced absorption in the visible region of the electromagnetic spectrum. DSSCs with a large area of ∼ 4.5 cm{sup 2} were fabricated and a photocurrent enhancement of ∼ 10% was obtained for plasmonic DSSC containing 0.3 wt.% of ∼ 15 nm Au NPs. Incident photon to current conversion efficiency data conclusively showed enhanced currents in the visible region of the polychromatic spectrum arising due to plasmon enhanced near-field effects of Au NPs around the absorbing dye molecules. - Highlights: • Preparation of TiO{sub 2} and TiO{sub 2}–Au films with a large area of ∼ 7.5 cm{sup 2} by a spray technique • An efficiency of ∼ 4.5% achieved by the large area plasmonic DSSC • Photocurrent enhancement due to SPR effects of gold NPs observed • Comparison of the spray and conventional doctor blade methods in DSSC performance • Demonstration of technological feasibility and versatility of a simple spray process.

  3. Robotics Scoping Study to Evaluate Advances in Robotics Technologies that Support Enhanced Efficiencies for Yucca Mountain Repository Operations

    Energy Technology Data Exchange (ETDEWEB)

    T. Burgess; M. Noakes; P. Spampinato

    2005-03-17

    This paper presents an evaluation of robotics and remote handling technologies that have the potential to increase the efficiency of handling waste packages at the proposed Yucca Mountain High-Level Nuclear Waste Repository. It is expected that increased efficiency will reduce the cost of operations. The goal of this work was to identify technologies for consideration as potential projects that the U.S. Department of Energy Office of Civilian Radioactive Waste Management, Office of Science and Technology International Programs, could support in the near future, and to assess their ''payback'' value. The evaluation took into account the robotics and remote handling capabilities planned for incorporation into the current baseline design for the repository, for both surface and subsurface operations. The evaluation, completed at the end of fiscal year 2004, identified where significant advantages in operating efficiencies could accrue by implementing any given robotics technology or approach, and included a road map for a multiyear R&D program for improvements to remote handling technology that support operating enhancements.

  4. A surface acoustic wave (SAW)-enhanced grating-coupling phase-interrogation surface plasmon resonance (SPR) microfluidic biosensor.

    Science.gov (United States)

    Sonato, A; Agostini, M; Ruffato, G; Gazzola, E; Liuni, D; Greco, G; Travagliati, M; Cecchini, M; Romanato, F

    2016-04-07

    A surface acoustic wave (SAW)-enhanced, surface plasmon resonance (SPR) microfluidic biosensor in which SAW-induced mixing and phase-interrogation grating-coupling SPR are combined in a single lithium niobate lab-on-a-chip is demonstrated. Thiol-polyethylene glycol adsorption and avidin/biotin binding kinetics were monitored by exploiting the high sensitivity of grating-coupling SPR under azimuthal control. A time saturation binding kinetics reduction of 82% and 24% for polyethylene and avidin adsorption was obtained, respectively, due to the fluid mixing enhancement by means of the SAW-generated chaotic advection. These results represent the first implementation of a nanostructured SAW-SPR microfluidic biochip capable of significantly improving the molecule binding kinetics on a single, portable device. In addition, the biochip here proposed is suitable for a great variety of biosensing applications.

  5. Surface modification of Cobalt ferrite nano-hollowspheres for inherent multiple photoluminescence and enhanced photocatalytic activities

    Science.gov (United States)

    Talukdar, Souvanik; Mandal, Dipika; Mandal, Kalyan

    2017-03-01

    Nano-hollow spheres (NHSs) are the new drift in magnetic nanostructures as they provide more surface area at nano length scale with enhanced magnetic properties compared to their nanoparticle counterpart. Here we reported the synthesis of biocompatible CoFe2O4 NHSs of diameter around 250 nm and emergence of intrinsic multiple photoluminescence from blue, green to red on modifying their surface with small organic ligands like tartrate. The surface modified NHSs also showed notable photocatalytic activity towards the degradation of environmentally malefic dyes like Methylene Blue and Rhodamine B. The surface modified NHSs are found to exhibit superior magnetic properties.

  6. Gold cluster coatings enhancing Raman scattering from surfaces: Ink analysis and document identification

    Science.gov (United States)

    Luo, Zhixun; Smith, Jordan C.; Goff, Trevor M.; Adair, James H.; Castleman, A. W.

    2013-09-01

    Based on the method of laser-ablation in liquids (LAL) with a strategy of bubbling nitrogen through a custom-made chamber, we prepared chemically-pure gold clusters which were found to be metastable for an extensive period of time beyond months. A practical use of discrimination among different surfaces is demonstrated here by applying the gold clusters as surface coatings which result in surface-enhanced Raman scattering (SERS) due to the surface plasmon resonance (SPR). This technique identifies various documents from different printers/copiers and written with different pen-inks. The stable and additive-free gold clusters enable repetitive examinations without impurity interference.

  7. Surface-enhanced raman spectroscopy substrate for arsenic sensing in groundwater

    Science.gov (United States)

    Yang, Peidong; Mulvihill, Martin; Tao, Andrea R.; Sinsermsuksakul, Prasert; Arnold, John

    2015-06-16

    A surface-enhanced Raman spectroscopy (SERS) substrate formed from a plurality of monolayers of polyhedral silver nanocrystals, wherein at least one of the monolayers has polyvinypyrrolidone (PVP) on its surface, and thereby configured for sensing arsenic is described. Highly active SERS substrates are formed by assembling high density monolayers of differently shaped silver nanocrystals onto a solid support. SERS detection is performed directly on this substrate by placing a droplet of the analyte solution onto the nanocrystal monolayer. Adsorbed polymer, polyvinypyrrolidone (PVP), on the surface of the nanoparticles facilitates the binding of both arsenate and arsenite near the silver surface, allowing for highly accurate and sensitive detection capabilities.

  8. Research on identification and determination of mixed pesticides in apples using surface enhanced Raman spectroscopy

    Science.gov (United States)

    Zhai, Chen; Li, Yongyu; Peng, Yankun; Xu, Tianfeng; Dhakal, Sagar; Chao, Kuanglin; Qin, Jianwei

    2015-05-01

    Residual pesticides in fruits and vegetables have become one of the major food safety concerns around the world. At present, routine analytical methods used for the determination of pesticide residue on the surface of fruits and vegetables are destructive, complex, time-consuming, high cost and not environmentally friendly. In this study, a novel Surface Enhanced Raman Spectroscopy (SERS) method with silver colloid was developed for fast and sensitive nondestructive detection of residual pesticides in fruits and vegetables by using a self-developed Raman system. SERS technology is a combination of Raman spectroscopy and nanotechnology. SERS can greatly enhance the Raman signal intensity, achieve single-molecule detection, and has a simple sample pre-treatment characteristic of high sensitivity and no damage; in recent years it has begun to be used in food safety testing research. In this study a rapid and sensitive method was developed to identify and analyze mixed pesticides of chlorpyrifos, deltamethrin and acetamiprid in apple samples by SERS. Silver colloid was used for SERS measurement by hydroxylamine hydrochloride reduced. The advantages of this method are seen in its fast preparation at room temperature, good reproducibility and immediate applicability. Raman spectrum is highly interfered by noise signals and fluorescence background, which make it too complex to get good result. In this study the noise signals and fluorescence background were removed by Savitzky-Golay filter and min-max signal adaptive zooming method. Under optimal conditions, pesticide residues in apple samples can be detected by SERS at 0.005 μg/cm2 and 0.002 μg/cm2 for individual acetamiprid and thiram, respectively. When mixing the two pesticides at low concentrations, their characteristic peaks can still be identified from the SERS spectrum of the mixture. Based on the synthesized material and its application in SERS operation, the method represents an ultrasensitive SERS performance

  9. Surface-enhanced Raman scattering of dipolar molecules by the graphene Fermi surface modulation with different dipole moments

    Science.gov (United States)

    Zhang, Mingjia; Leng, Yandan; Huang, Jing; Yu, JiaoJiao; Lan, Zhenggang; Huang, Changshui

    2017-12-01

    We report the modulation of Raman scattering spectrum of chromophore/graphene hybrids by tunning the molecular polarization with different terminal groups (methyl, methoxy, nitrile, and two nitros). Based on the density functional theory, the specific dipole moment values of the chromophore molecules are calculated. An obvious surface-enhanced Raman scattering (SERS) was observed and the scattering intensity of molecule increases with enlarged dipole moment. According to the analysis of G band Raman shifts of graphene, the enhancement of the Raman signal can be attributed to strong electronic coupling between graphene and chromophore, which is closely related with the modulation of graphene Fermi surface by changing the dipole moment of the molecule. Besides, the optimization of the ground state geometry and the binding energy of the hybrids were also calculated with the Density Functional Based Tight Bonding (DFTB) method, which confirms that the enhanced Raman scattering of molecules on graphene arises from the improved energy level matching between graphene Fermi surface and molecular band, further providing a new way to design novel SERS devices.

  10. Normal and surface-enhanced Raman spectroscopy of nitroazobenzene submonolayers and multilayers on carbon and silver surfaces.

    Science.gov (United States)

    Liang, Haihe; Tian, Hong; McCreery, Richard L

    2007-06-01

    Raman and ultraviolet-visible (UV-Vis) absorption spectra were obtained for nitroazobenzene (NAB) chemisorbed on smooth and rough silver, and they were compared to published spectra for NAB on sp(2) hybridized pyrolyzed photoresist film (PPF) surfaces. High signal-to-noise ratio Raman spectra were obtained for 4.5 nm thick NAB films on PPF and smooth Ag due to significant enhancement of the NAB scattering relative to that observed in solution. The UV-Vis spectra of chemisorbed NAB exhibited a significant shift toward longer wavelength, thus bringing the NAB absorption closer to the 514.5 nm laser wavelength. The red shift was larger for PPF than for smooth Ag, consistent with the approximately 5x stronger Raman signal obtained on PPF. Deposition of Ag onto quartz without a chromium adhesion layer produced a rough Ag surface that enhanced the Raman spectrum of chemisorbed NAB by a factor of approximately 1000, as expected for roughened Ag due to electromagnetic field enhancement. The strong Raman signal permitted observation of NAB at low coverage and revealed changes in the NAB spectrum as the film progressed from submonolayer to multilayer thicknesses. Finally, deposition of Ag onto PPF/NAB samples through a metal grid produced Ag squares on top of the NAB, which enhanced the Raman scattering of the NAB layer by a factor of approximately 100. Deposition of a final conducting film on the Ag squares should permit in situ observation of a wide range of molecules in operating molecular electronic junctions.

  11. The exploration technology and application of sea surface wave

    Science.gov (United States)

    Wang, Y.

    2016-12-01

    In order to investigate the seismic velocity structure of the shallow sediments in the Bohai Sea of China, we conduct a shear-wave velocity inversion of the surface wave dispersion data from a survey of 12 ocean bottom seismometers (OBS) and 377 shots of a 9000 inch3 air gun. With OBS station spacing of 5 km and air gun shot spacing of 190 m, high-quality Rayleigh wave data were recorded by the OBSs within 0.4 5 km offset. Rayleigh wave phase velocity dispersion for the fundamental mode and first overtone in the frequency band of 0.9 3.0 Hz were retrieved with the phase-shift method and inverted for the shear-wave velocity structure of the shallow sediments with a damped iterative least-square algorithm. Pseudo 2-D shear-wave velocity profiles with depth to 400 m show coherent features of relatively weak lateral velocity variation. The uncertainty in shear-wave velocity structure was also estimated based on the pseudo 2-D profiles from 6 trial inversions with different initial models, which suggest a velocity uncertainty < 30 m/s for most parts of the 2-D profiles. The layered structure with little lateral variation may be attributable to the continuous sedimentary environment in the Cenozoic sedimentary basin of the Bohai Bay basin. The shear-wave velocity of 200 300 m/s in the top 100 m of the Bohai Sea floor may provide important information for offshore site response studies in earthquake engineering. Furthermore, the very low shear-wave velocity structure (200 700 m/s) down to 400 m depth could produce a significant travel time delay of 1 s in the S wave arrivals, which needs to be considered to avoid serious bias in S wave traveltime tomographic models.

  12. TECHNOLOGIES TO ENHANCE OPERATION OF THE EXISTING NATURAL GAS COMPRESSION INFRASTRUCTURE

    Energy Technology Data Exchange (ETDEWEB)

    Anthony J. Smalley; Ralph E. Harris; Gary D. Bourn

    2004-08-01

    This report documents work performed in Phase I of the project entitled: ''Technologies to Enhance Operation of the Existing Natural Gas Compression Infracture''. The project objective is to develop and substantiate methods for operating integral engine/compressors in gas pipeline service, which reduce fuel consumption, increase capacity, and enhance mechanical integrity. The report describes a number of potential enhancements to the existing natural gas compression infrastructure that have been identified and tested on four different integral engine/compressors in natural gas transmission service.

  13. Technology Applied to ELT: Reviewing Practical Uses to Enhance English Teaching Programs

    Directory of Open Access Journals (Sweden)

    Javier Rojas Serrano

    2007-12-01

    Full Text Available In this paper, the author reports on some of the areas of technology currently used in the teaching and learning of languages, and reviews some of the uses of technological tools that are present in the English Adult Program and activities carried out at The Centro Colombo Americano (CCA in Bogota, Colombia. After briefly describing what is being applied worldwide in terms of what is being done at the CCA, some suggestions are offered in order to enhance the English teaching and learning processes through the use of new technologies.

  14. Technology and Research Requirements for Combating Human Trafficking: Enhancing Communication, Analysis, Reporting, and Information Sharing

    Energy Technology Data Exchange (ETDEWEB)

    Kreyling, Sean J.; West, Curtis L.; Olson, Jarrod

    2011-03-17

    DHS’ Science & Technology Directorate directed PNNL to conduct an exploratory study on the domain of human trafficking in the Pacific Northwest in order to examine and identify technology and research requirements for enhancing communication, analysis, reporting, and information sharing – activities that directly support efforts to track, identify, deter, and prosecute human trafficking – including identification of potential national threats from smuggling and trafficking networks. This effort was conducted under the Knowledge Management Technologies Portfolio as part of the Integrated Federal, State, and Local/Regional Information Sharing (RISC) and Collaboration Program.

  15. Identification of surface hydrogen enhancements within the Moon’s Shackleton crater

    Science.gov (United States)

    Miller, Richard S.; Lawrence, David J.; Hurley, Dana M.

    2014-05-01

    Bulk surface hydrogen enhancements have been identified within the Moon’s Shackleton crater. Using an analysis of fast and epithermal neutron data from the Lunar Prospector mission, the permanently shadowed region (PSR) within this crater has a surface concentration of 0.72 ± 0.13 wt.% water equivalent hydrogen (WEH). In contrast, hydrogen enhancements within other polar PSRs such as Cabeus are likely buried under more than 10 cm of hydrogen-poor regolith. Subsurface hydrogen absent a surficial counterpart implies an episodic delivery mechanism. The burial depth suggests the epoch of hydrogen deposition was at least 100 myr ago if impact gardening is the dominant mechanism for volatile transport to depth. Shackleton crater’s surface enhancement may be related to its thermal environment, ∼30 K warmer than other south pole PSRs, in which thermal processes control the vertical migration of hydrogen within Shackleton but inhibit migration in colder regions.

  16. Theory of hyperbolic stratified nanostructures for surface-enhanced Raman scattering

    Science.gov (United States)

    Wong, Herman M. K.; Dezfouli, Mohsen Kamandar; Axelrod, Simon; Hughes, Stephen; Helmy, Amr S.

    2017-11-01

    We theoretically investigate the enhancement of surface enhanced Raman spectroscopy (SERS) using hyperbolic stratified nanostructures and compare to metal nanoresonators. The photon Green function of each nanostructure within its environment is first obtained from a semianalytical modal theory, which is used in a quantum optics formalism of the molecule-nanostructure interaction to model the SERS spectrum. An intuitive methodology is presented for calculating the single-molecule enhancement factor (SMEF), which is also able to predict known experimental SERS enhancement factors of a gold nanodimer. We elucidate the important figures-of-merit of the enhancement and explore these for different designs. We find that the use of hyperbolic stratified materials can enhance the photonic local density of states (LDOS) by close to two times in comparison to pure metal nanostructures, when both designed to work at the same operating wavelengths. However, the increased LDOS is accompanied by higher electric field concentration within the lossy hyperbolic material, which leads to increased quenching that serves to reduce the overall detected SERS enhancement in the far field. For nanoresonators with resonant localized surface plasmon wavelengths in the near-infrared, the SMEF for the hyperbolic stratified nanostructure is approximately one order of magnitude lower than the pure metal counterpart. Conversely, we show that by detecting the Raman signal using a near-field probe, hyperbolic materials can provide an improvement in SERS enhancement compared to using pure metal nanostructures when the probe is sufficiently close (<50 nm ) to the Raman active molecule at the plasmonic hotspot.

  17. Enhanced oxygen reduction activity on surface-decorated perovskite thin films for solid oxide fuel cells

    KAUST Repository

    Mutoro, Eva

    2011-01-01

    Surface-decoration of perovskites can strongly affect the oxygen reduction activity, and therefore is a new and promising approach to improve SOFC cathode materials. In this study, we demonstrate that a small amount of secondary phase on a (001) La 0.8Sr 0.2CoO 3-δ (LSC) surface can either significantly activate or passivate the electrode. LSC (001) microelectrodes prepared by pulsed laser deposition on a (001)-oriented yttria-stabilized zirconia (YSZ) substrate were decorated with La-, Co-, and Sr-(hydr)oxides/carbonates. "Sr"-decoration with nanoparticle coverage in the range from 50% to 80% of the LSC surface enhanced the surface exchange coefficient, k q, by an order of magnitude while "La"- decoration and "Co"-decoration led to no change and reduction in k q, respectively. Although the physical origin for the enhancement is not fully understood, results from atomic force microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy suggest that the observed k q enhancement for "Sr"-decorated surfaces can be attributed largely to catalytically active interface regions between surface Sr-enriched particles and the LSC surface. © 2011 The Royal Society of Chemistry.

  18. Enhancement of nitric oxide release and hemocompatibility by surface chirality of D-tartaric acid grafting

    Science.gov (United States)

    Han, Honghong; Wang, Ke; Fan, Yonghong; Pan, Xiaxin; Huang, Nan; Weng, Yajun

    2017-12-01

    Nitric Oxide (NO) generation from endogenous NO-donors catalyzed by diselenide modified biomaterials has been reported. Here we reported surface chirality by L-tartaric acid and D-tartaric acid grafting on the outermost showed a significant impact on diselenide modified biomaterials, which modulated protein adsorption, NO release and anti-platelet adhesion properties. D-tartaric acid grafted surface showed more blood protein adsorption than that of L-surfaces by QCM analysis, however, ELISA analysis disclosed less fibrinogen denatured on the D surfaces. Due to the surface ratio of selenium decreasing, NO release catalyzed by L-tartaric acid grafting on the outermost significantly decreased in comparison to that of only selenocystamine immobilized surfaces. While NO release catalyzed by D-tartaric acid grafting on the outermost didn't decrease and was similar with that of selenocystamine immobilized surfaces. Surface chirality combined with NO release had synergetic effects on platelet adhesion, and it showed the lowest number of platelets adhered on the D-tartaric acid grafted surfaces. Thus surface chirality from D-tartaric acid grafting enhanced hemocompatibility of the surface in this study. Our work provides new insights into engineering novel blood contacting biomaterials by taking into account surface chirality.

  19. Surface-enhanced fluorescence in metal nanoparticle-doped polymer nanofibers via waveguiding excitation

    Science.gov (United States)

    Yu, Jiaxin; Liao, Feng; Liu, Fang; Gu, Fuxing; Zeng, Heping

    2017-04-01

    We report a waveguiding excitation-based approach for surface-enhanced fluorescence. As high as 17-fold enhanced fluorescence intensity of Rhodamine 6G molecules is realized by gold nanoparticles embedded in polymer nanofibers. The enhancement results not only from the spatial confinement of light by the nanofibers but also from the wavelength match among the excitation laser, the localized surface plasmon resonance of nanoparticles, and the absorption band of dyes. On the basis of the enhancement and high-efficient waveguiding regime, the required excitation power for detectable fluorescence is decreased to the 20 nW level, which is about 50 times lower than that by free-space excitation. These fluorophore/nanoparticle-doped nanofibers may find applications in compact and energy-efficient optical devices of chemical analysis and biosensing.

  20. Plasmonic photoluminescence for recovering native chemical information from surface-enhanced Raman scattering

    Science.gov (United States)

    Lin, Kai-Qiang; Yi, Jun; Zhong, Jin-Hui; Hu, Shu; Liu, Bi-Ju; Liu, Jun-Yang; Zong, Cheng; Lei, Zhi-Chao; Wang, Xiang; Aizpurua, Javier; Esteban, Rubén; Ren, Bin

    2017-03-01

    Surface-enhanced Raman scattering (SERS) spectroscopy has attracted tremendous interests as a highly sensitive label-free tool. The local field produced by the excitation of localized surface plasmon resonances (LSPRs) dominates the overall enhancement of SERS. Such an electromagnetic enhancement is unfortunately accompanied by a strong modification in the relative intensity of the original Raman spectra, which highly distorts spectral features providing chemical information. Here we propose a robust method to retrieve the fingerprint of intrinsic chemical information from the SERS spectra. The method is established based on the finding that the SERS background originates from the LSPR-modulated photoluminescence, which contains the local field information shared also by SERS. We validate this concept of retrieval of intrinsic fingerprint information in well controlled single metallic nanoantennas of varying aspect ratios. We further demonstrate its unambiguity and generality in more complicated systems of tip-enhanced Raman spectroscopy (TERS) and SERS of silver nanoaggregates.