Sample records for electron demand darinv

  1. A cyclic-RGD-BioShuttle functionalized with TMZ by DARinv “Click Chemistry” targeted to αvβ3 integrin for therapy

    PubMed Central

    Braun, Klaus; Wiessler, Manfred; Pipkorn, Rüdiger; Ehemann, Volker; Bäuerle, Tobias; Fleischhacker, Heinz; Müller, Gabriele; Lorenz, Peter; Waldeck, Waldemar

    2010-01-01

    Clinical experiences often document, that a successful tumor control requires high doses of drug applications. It is widely believed that unavoidable adverse reactions could be minimized by using gene-therapeutic strategies protecting the tumor-surrounding healthy tissue as well as the bone-marrow. One new approach in this direction is the use of “Targeted Therapies” realizing a selective drug targeting to gain effectual amounts at the target site, even with drastically reduced application doses. MCF-7 breast cancer cells expressing the αvβ3 [alpha(v)beta(3)] integrin receptor are considered as appropriate candidates for such a targeted therapy. The modularly composed BioShuttle carrier consisting of different units designed to facilitate the passage across the cell membranes and for subcellular addressing of diagnostic and/or therapeutic molecules could be considered as an eligible delivery platform. Here we used the cyclic RGD-BioShuttle as a carrier for temozolomide (TMZ) at the αvβ3 integrin receptor realizing local TMZ concentrations sufficient for cell killing. The IC50 values are 12 µMol/L in the case of cRGD-BioShuttle-TMZ and 100 µMol/L for underivatized TMZ, which confirms the advantage of TMZ reformulation to realize local concentrations sufficient for cell killing. Our paper focuses on the design, synthesis and application of the cRGD-BioShuttle conjugate composed of the cyclic RGD, a αvβ3 integrin-ligand, ligated to the cytotoxic drug TMZ. The ligation was carried out by the Diels Alder Reaction with inverse electron demand (DARinv). PMID:20922134

  2. 12 CFR 1215.8 - Timing and form of demands and requests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... section. (g) Every demand or request must include the legal proceeding's caption and docket number, the forum; the name, address, phone number, State Bar number, and, if available, electronic mail address of..., address, phone number, and electronic mail address of the pro-se party); and a statement of the demanding...

  3. Synthesis of 3,4-dihydro-1,8-naphthyridin-2(1H)-ones via microwave-activated inverse electron-demand Diels–Alder reactions

    PubMed Central

    Fadel, Salah; Hajbi, Youssef; Khouili, Mostafa; Lazar, Said

    2014-01-01

    Summary Substituted 3,4-dihydro-1,8-naphthyridin-2(1H)-ones have been synthesized with the inverse electron-demand Diels–Alder reaction from 1,2,4-triazines bearing an acylamino group with a terminal alkyne side chain. Alkynes were first subjected to the Sonogashira cross-coupling reaction with aryl halides, the product of which then underwent an intramolecular inverse electron-demand Diels–Alder reaction to yield 5-aryl-3,4-dihydro-1,8-naphthyridin-2(1H)-ones by an efficient synthetic route. PMID:24605148

  4. Synthesis of 3,4-dihydro-1,8-naphthyridin-2(1H)-ones via microwave-activated inverse electron-demand Diels-Alder reactions.

    PubMed

    Fadel, Salah; Hajbi, Youssef; Khouili, Mostafa; Lazar, Said; Suzenet, Franck; Guillaumet, Gérald

    2014-01-01

    Substituted 3,4-dihydro-1,8-naphthyridin-2(1H)-ones have been synthesized with the inverse electron-demand Diels-Alder reaction from 1,2,4-triazines bearing an acylamino group with a terminal alkyne side chain. Alkynes were first subjected to the Sonogashira cross-coupling reaction with aryl halides, the product of which then underwent an intramolecular inverse electron-demand Diels-Alder reaction to yield 5-aryl-3,4-dihydro-1,8-naphthyridin-2(1H)-ones by an efficient synthetic route.

  5. Vacuum and the electron tube industry

    NASA Astrophysics Data System (ADS)

    Redhead, P. A.

    2005-07-01

    The electron tube industry started with the patenting of the thermionic diode by John Ambrose Fleming in 1904. The vacuum technology used by the infant tube industry was copied from the existing incandescent lamp industry. The growing demands for electron tubes for the military in the first world war led to major improvements in pumps and processing methods. By the 1920s, mass production methods were developing to satisfy the demands for receiving tubes by the burgeoning radio industry. Further expansion in the 1930s and 1940s resulted in improvements in automatic equipment for pumping vacuum tubes leading to the massive production rates of electron tubes in the second world war and the following two decades. The demand for radar during the war resulted in the development of techniques for large-scale production of microwave tubes and CRTs, the latter technology being put to good use later in TV picture tube production. The commercial introduction of the transistor ended the massive demand for receiving tubes. This review concentrates on the vacuum technology developed for receiving tube production.

  6. Non-electronic communication aids for people with complex communication needs.

    PubMed

    Iacono, Teresa; Lyon, Katie; West, Denise

    2011-10-01

    Non-electronic communication aids provide one form of augmentative and alternative communication (AAC) for people with complex communication needs. The aim here was to explore non-electronic communication aids as one AAC option and research challenges. This aim was addressed by reviewing funding for the provision of AAC systems, data from an Australian pilot project providing non-electronic communication aids, an audit of aided AAC published studies (2000-2009), and discussion of the review literature. Combined, these sources indicate that although there is great demand for non-electronic communication aids, funding schemes, both in Australia and internationally, have focused on electronic communication aids. Such funding has usually failed to meet the total device costs and has not provided for adequate speech-language pathology support. Data from the pilot indicated the demand for non-electronic communication aids, and patterns suggest potential factors that govern the types selected. Despite the high demand for non-electronic aids, the research literature has tended to focus on electronic communication aids, including within intervention studies and addressing design features and long-term outcomes. Concerns about ensuring that AAC systems are chosen according to the assessed needs of individuals are discussed within the context of limitations in outcomes research and appropriate outcome measures.

  7. Oxide nanoelectronics on demand.

    PubMed

    Cen, Cheng; Thiel, Stefan; Mannhart, Jochen; Levy, Jeremy

    2009-02-20

    Electronic confinement at nanoscale dimensions remains a central means of science and technology. We demonstrate nanoscale lateral confinement of a quasi-two-dimensional electron gas at a lanthanum aluminate-strontium titanate interface. Control of this confinement using an atomic force microscope lithography technique enabled us to create tunnel junctions and field-effect transistors with characteristic dimensions as small as 2 nanometers. These electronic devices can be modified or erased without the need for complex lithographic procedures. Our on-demand nanoelectronics fabrication platform has the potential for widespread technological application.

  8. Scenarios for Demand Growth of Metals in Electricity Generation Technologies, Cars, and Electronic Appliances

    PubMed Central

    2018-01-01

    This study provides scenarios toward 2050 for the demand of five metals in electricity production, cars, and electronic appliances. The metals considered are copper, tantalum, neodymium, cobalt, and lithium. The study shows how highly technology-specific data on products and material flows can be used in integrated assessment models to assess global resource and metal demand. We use the Shared Socio-economic Pathways as implemented by the IMAGE integrated assessment model as a starting point. This allows us to translate information on the use of electronic appliances, cars, and renewable energy technologies into quantitative data on metal flows, through application of metal content estimates in combination with a dynamic stock model. Results show that total demand for copper, neodymium, and tantalum might increase by a factor of roughly 2 to 3.2, mostly as a result of population and GDP growth. The demand for lithium and cobalt is expected to increase much more, by a factor 10 to more than 20, as a result of future (hybrid) electric car purchases. This means that not just demographics, but also climate policies can strongly increase metal demand. This shows the importance of studying the issues of climate change and resource depletion together, in one modeling framework. PMID:29533657

  9. Scenarios for Demand Growth of Metals in Electricity Generation Technologies, Cars, and Electronic Appliances.

    PubMed

    Deetman, Sebastiaan; Pauliuk, Stefan; van Vuuren, Detlef P; van der Voet, Ester; Tukker, Arnold

    2018-04-17

    This study provides scenarios toward 2050 for the demand of five metals in electricity production, cars, and electronic appliances. The metals considered are copper, tantalum, neodymium, cobalt, and lithium. The study shows how highly technology-specific data on products and material flows can be used in integrated assessment models to assess global resource and metal demand. We use the Shared Socio-economic Pathways as implemented by the IMAGE integrated assessment model as a starting point. This allows us to translate information on the use of electronic appliances, cars, and renewable energy technologies into quantitative data on metal flows, through application of metal content estimates in combination with a dynamic stock model. Results show that total demand for copper, neodymium, and tantalum might increase by a factor of roughly 2 to 3.2, mostly as a result of population and GDP growth. The demand for lithium and cobalt is expected to increase much more, by a factor 10 to more than 20, as a result of future (hybrid) electric car purchases. This means that not just demographics, but also climate policies can strongly increase metal demand. This shows the importance of studying the issues of climate change and resource depletion together, in one modeling framework.

  10. Association between Emotional Symptoms and Job Demands in an Asian Electronics Factory.

    PubMed

    Huang, Wei-Lieh; Guo, Yue Leon; Chen, Pau-Chung; Wang, Jui; Chu, Po-Ching

    2017-09-19

    Various work-related issues including mental health have been described for the electronic industry. Although East Asian countries play important roles in the electronics industry, the association between job demands and emotional symptoms has been rarely examined. The present study recruited 603 workers from either office or clean room environments in an electronics factory in Taiwan. Their personal factors, work-related factors, and emotional symptoms were assessed by a self-administered questionnaire. The symptoms of depression and hostility were reported in 24.88% and 24.38% of the subjects, respectively, while 14.93% reported both. A multivariate analysis showed that, overall, women workers were more likely to have emotional symptoms than male workers (odds ration (OR) = 1.50, 95% CI = 1.02-2.18). Among clean room workers, working under high pressure (OR = 1.84, 95% CI = 1.05-3.21), conflicting demands (OR = 2.15, 95% CI = 1.30-3.57), and social isolation at work (OR = 2.99, 95% CI = 1.23-7.30) were associated with emotional symptoms. The findings suggest that in the Asian electronics industry, for women, working under high pressure, conflicting demands, and social isolation at work are risk factors for emotional symptoms, especially for clean room workers. Further large-scale, longitudinal studies are necessary to confirm and prevent the mental health problems in this fast-evolving, highly competitive industry.

  11. Association between Emotional Symptoms and Job Demands in an Asian Electronics Factory

    PubMed Central

    Huang, Wei-Lieh; Guo, Yue Leon; Chen, Pau-Chung; Wang, Jui; Chu, Po-Ching

    2017-01-01

    Various work-related issues including mental health have been described for the electronic industry. Although East Asian countries play important roles in the electronics industry, the association between job demands and emotional symptoms has been rarely examined. The present study recruited 603 workers from either office or clean room environments in an electronics factory in Taiwan. Their personal factors, work-related factors, and emotional symptoms were assessed by a self-administered questionnaire. The symptoms of depression and hostility were reported in 24.88% and 24.38% of the subjects, respectively, while 14.93% reported both. A multivariate analysis showed that, overall, women workers were more likely to have emotional symptoms than male workers (odds ration (OR) = 1.50, 95% CI = 1.02–2.18). Among clean room workers, working under high pressure (OR = 1.84, 95% CI = 1.05–3.21), conflicting demands (OR = 2.15, 95% CI = 1.30–3.57), and social isolation at work (OR = 2.99, 95% CI = 1.23–7.30) were associated with emotional symptoms. The findings suggest that in the Asian electronics industry, for women, working under high pressure, conflicting demands, and social isolation at work are risk factors for emotional symptoms, especially for clean room workers. Further large-scale, longitudinal studies are necessary to confirm and prevent the mental health problems in this fast-evolving, highly competitive industry. PMID:28925986

  12. The Use of the Academic Electronic Medical Record (EMR) to Develop Critical Thinking Skills in an Associate Degree Nursing Mobility Program

    ERIC Educational Resources Information Center

    Wlodyga, Linda J.

    2010-01-01

    In an attempt to prepare new graduate nurses to meet the demands of health care delivery systems, the use of computer-based clinical information systems that combine hands-on experience with computer based information systems was explored. Since the introduction of Electronic Medical Records (EMR) nearly two decades ago, the demand for nurses to…

  13. Micro-Structural Study of Fretting Contact Caused by the Difference of the Tin Plating Thickness

    NASA Astrophysics Data System (ADS)

    Ito, Tetsuya; Sawada, Shigeru; Hattori, Yasuhiro; Saitoh, Yasushi; Tamai, Terutaka; Iida, Kazuo

    In recent years, there has been increasing demand to miniaturize wiring harness connectors in automobiles due to the increasing volume of electronic equipment and the reduction of the installation space allocated for the electronic equipment in automobiles for the comfort of the passengers. With this demand, contact failure caused by the fretting corrosion is expected to become a serious problem. In this report, we examined micro-structural observations of fretting contacts of two different tin plating thicknesses using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) and so on. Based on the results, we compared the microstructure difference of fretting contact caused by the difference of the tin plating thickness.

  14. NASA STI Program Seminar: Electronic documents

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The theme of this NASA Scientific and Technical Information Program Seminar was electronic documents. Topics covered included Electronic Documents Management at the CASI, the Impact of Electronic Publishing on User Expectations and Searching Image Record Management, Secondary Publisher Considerations for Electronic Journal Literature, and the Technical Manual Publishing On Demand System (TMPODS).

  15. Future Data Communication Architectures for Safety Critical Aircraft Cabin Systems

    NASA Astrophysics Data System (ADS)

    Berkhahn, Sven-Olaf

    2012-05-01

    The cabin of modern aircraft is subject to increasing demands for fast reconfiguration and hence flexibility. These demands require studies for new network architectures and technologies of the electronic cabin systems, which consider also weight and cost reductions as well as safety constraints. Two major approaches are in consideration to reduce the complex and heavy wiring harness: the usage of a so called hybrid data bus technology, which enables the common usage of the same data bus for several electronic cabin systems with different safety and security requirements and the application of wireless data transfer technologies for electronic cabin systems.

  16. Bioelectronic Learning: The Effects of Electronic Media on a Developing Brain.

    ERIC Educational Resources Information Center

    Sylwester, Robert

    1997-01-01

    Considers the effects of electronic media on the developing brains of children. Topics include the attentional demands of electronic media; commercial sponsorship; brain development, including memory systems and response systems; and what a developing mind can bring to the electronic media. (LRW)

  17. Better service, greater efficiency : transit management for demand response systems

    DOT National Transportation Integrated Search

    1999-01-01

    This brochure briefly describes different technologies which can enhance demand response transit systems. It covers automated scheduling and dispatching, mobile data terminals, electronic identification cards, automatic vehicle location, and geograph...

  18. The response of cyclic electron flow around photosystem I to changes in photorespiration and nitrate assimilation.

    PubMed

    Walker, Berkley J; Strand, Deserah D; Kramer, David M; Cousins, Asaph B

    2014-05-01

    Photosynthesis captures light energy to produce ATP and NADPH. These molecules are consumed in the conversion of CO2 to sugar, photorespiration, and NO3(-) assimilation. The production and consumption of ATP and NADPH must be balanced to prevent photoinhibition or photodamage. This balancing may occur via cyclic electron flow around photosystem I (CEF), which increases ATP/NADPH production during photosynthetic electron transport; however, it is not clear under what conditions CEF changes with ATP/NADPH demand. Measurements of chlorophyll fluorescence and dark interval relaxation kinetics were used to determine the contribution of CEF in balancing ATP/NADPH in hydroponically grown Arabidopsis (Arabidopsis thaliana) supplied different forms of nitrogen (nitrate versus ammonium) under changes in atmospheric CO2 and oxygen. Measurements of CEF were made under low and high light and compared with ATP/NADPH demand estimated from CO2 gas exchange. Under low light, contributions of CEF did not shift despite an up to 17% change in modeled ATP/NADPH demand. Under high light, CEF increased under photorespiratory conditions (high oxygen and low CO2), consistent with a primary role in energy balancing. However, nitrogen form had little impact on rates of CEF under high or low light. We conclude that, according to modeled ATP/NADPH demand, CEF responded to energy demand under high light but not low light. These findings suggest that other mechanisms, such as the malate valve and the Mehler reaction, were able to maintain energy balance when electron flow was low but that CEF was required under higher flow.

  19. The health literacy demands of electronic personal health records (e-PHRs): An integrative review to inform future inclusive research.

    PubMed

    Hemsley, Bronwyn; Rollo, Megan; Georgiou, Andrew; Balandin, Susan; Hill, Sophie

    2018-01-01

    To integrate the findings of research on electronic personal health records (e-PHRs) for an understanding of their health literacy demands on both patients and providers. We sought peer-reviewed primary research in English addressing the health literacy demands of e-PHRs that are online and allow patients any degree of control or input to the record. A synthesis of three theoretical models was used to frame the analysis of 24 studies. e-PHRs pose a wide range of health literacy demands on both patients and health service providers. Patient participation in e-PHRs relies not only on their level of education and computer literacy, and attitudes to sharing health information, but also upon their executive function, verbal expression, and understanding of spoken and written language. The multiple health literacy demands of e-PHRs must be considered when implementing population-wide initiatives for storing and sharing health information using these systems. The health literacy demands of e-PHRs are high and could potentially exclude many patients unless strategies are adopted to support their use of these systems. Developing strategies for all patients to meet or reduce the high health literacy demands of e-PHRs will be important in population-wide implementation. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. 19 CFR 163.6 - Production and examination of entry and other records and witnesses; penalties.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... entry records were required at the time of entry. Any oral demand for entry records shall be followed by a written or electronic demand. The entry records shall be produced within 30 calendar days of receipt of the demand or within any shorter period as Customs may prescribe when the entry records are...

  1. Next-generation materials for future synchrotron and free-electron laser sources

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Assoufid, Lahsen; Graafsma, Heinz

    We show that the development of new materials and improvements of existing ones are at the root of the spectacular recent developments of new technologies for synchrotron storage rings and free-electron laser sources. This holds true for all relevant application areas, from electron guns to undulators, x-ray optics, and detectors. As demand grows for more powerful and efficient light sources, efficient optics, and high-speed detectors, an overview of ongoing materials research for these applications is timely. In this article, we focus on the most exciting and demanding areas of materials research and development for synchrotron radiation optics and detectors. Materialsmore » issues of components for synchrotron and free-electron laser accelerators are briefly discussed. Lastly, the articles in this issue expand on these topics.« less

  2. Next-generation materials for future synchrotron and free-electron laser sources

    DOE PAGES

    Assoufid, Lahsen; Graafsma, Heinz

    2017-06-09

    We show that the development of new materials and improvements of existing ones are at the root of the spectacular recent developments of new technologies for synchrotron storage rings and free-electron laser sources. This holds true for all relevant application areas, from electron guns to undulators, x-ray optics, and detectors. As demand grows for more powerful and efficient light sources, efficient optics, and high-speed detectors, an overview of ongoing materials research for these applications is timely. In this article, we focus on the most exciting and demanding areas of materials research and development for synchrotron radiation optics and detectors. Materialsmore » issues of components for synchrotron and free-electron laser accelerators are briefly discussed. Lastly, the articles in this issue expand on these topics.« less

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Duan, H. Diessel; Lubner, Carolyn E.; Tokmina-Lukaszewska, Monika

    A newly-recognized third fundamental mechanism of energy conservation in biology, electron bifurcation, uses free energy from exergonic redox reactions to drive endergonic redox reactions. Flavin-based electron bifurcation furnishes low potential electrons to demanding chemical reactions such as reduction of dinitrogen to ammonia. We employed the heterodimeric flavoenzyme FixAB from the diazotrophic bacterium Rhodopseudomonas palustris to elucidate unique properties that underpin flavin-based electron bifurcation.

  4. Characterization of Quantum Efficiency and Robustness of Cesium-Based Photocathodes

    DTIC Science & Technology

    2010-01-01

    photocathodes produce picosecond-pulsed, high- current electron beams for photoinjection applications like free electron lasers . In photoinjectors, a...pulsed drive laser incident on the photocathode causes photoemission of short, dense bunches of electrons, which are then accelerated into a...relativistic, high quality beam. Future free electron lasers demand reliable photocathodes with long-lived quantum efficiency at suitable drive laser

  5. Investigating a Drop-on-Demand Microdispenser for Standardized Sample Preparation

    DTIC Science & Technology

    2012-09-01

    Demand Microdispenser for Standardized Sample Preparation Ellen L. Holthoff, Mikella E. Farrell, and Paul M. Pellegrino Sensors and Electron Devices...instrument. The use of a gravimetric method, such as a quartz crystal microbalance4 ( QCM ) or a sensitive microbalance as discussed in this report, is

  6. Cross-Diels-Alder reactions of 6-oxo-1-sulfonyl-1,6-dihydropyridine-3-carboxylates.

    PubMed

    Teyssot, Marie-Laure; Lormier, Anh-Tuan; Chataigner, Isabelle; Piettre, Serge R

    2007-03-30

    Electron-poor 6-oxo-1-sulfonyl-1,6-dihydropyridine-3-carboxylates 1b-d undergo cross-Diels-Alder reactions with electron-rich dienes 4a-f under hyperbaric conditions, reacting either as dienophiles to yield normal-electron-demand (NED) cycloadducts 10 and/or 11 or as dienes to give inverse-electron-demand (IED) cycloadducts 12 and/or 13. The latter are converted into 14 and/or 15 through an NED cycloaddition with a second equivalent of electron-rich diene. Acyclic dienes display a propensity to yield NED products, whereas cyclic dienes tend to favor IED cycloadducts. High-pressure activation compares favorably with thermal or microwave activation in terms of both yields and suppression of the transformation of 1 into unreactive pyridines 3. Whereas the Cope rearrangement from IED to NED occurs under thermal conditions, no evidence of its involvement under high pressure could be detected. These and other data point to similar activation energies for the NED and IED processes under these conditions.

  7. Distinct properties underlie flavin-based electron bifurcation in a novel electron transfer flavoprotein FixAB from Rhodopseudomonas palustris

    DOE PAGES

    Duan, H. Diessel; Lubner, Carolyn E.; Tokmina-Lukaszewska, Monika; ...

    2018-02-09

    A newly-recognized third fundamental mechanism of energy conservation in biology, electron bifurcation, uses free energy from exergonic redox reactions to drive endergonic redox reactions. Flavin-based electron bifurcation furnishes low potential electrons to demanding chemical reactions such as reduction of dinitrogen to ammonia. We employed the heterodimeric flavoenzyme FixAB from the diazotrophic bacterium Rhodopseudomonas palustris to elucidate unique properties that underpin flavin-based electron bifurcation.

  8. Electronic Publishing and Library Technical Services.

    ERIC Educational Resources Information Center

    Aveney, Brian

    1984-01-01

    Trends in electronic editions, on-demand publishing, and online publishing are reviewed and their potential effects on library services and organization are discussed, including library material selection, acquisitions, cataloging, serials, circulation, and home printers. Thirteen references are provided. (EJS)

  9. Engineered hybrid cardiac patches with multifunctional electronics for online monitoring and regulation of tissue function

    PubMed Central

    Feiner, Ron; Engel, Leeya; Fleischer, Sharon; Malki, Maayan; Gal, Idan; Shapira, Assaf; Shacham-Diamand, Yosi; Dvir, Tal

    2016-01-01

    In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells are seeded within three-dimensional porous scaffolds to create functional cardiac patches. However, current cardiac patches do not allow for online monitoring and reporting of engineered-tissue performance, and do not interfere to deliver signals for patch activation or to enable its integration with the host. Here, we report an engineered cardiac patch that integrates cardiac cells with flexible, free-standing electronics and a 3D nanocomposite scaffold. The patch exhibited robust electronic properties, enabling the recording of cellular electrical activities and the on-demand provision of electrical stimulation for synchronizing cell contraction. We also show that electroactive polymers containing biological factors can be deposited on designated electrodes to release drugs in the patch microenvironment on-demand. We expect that the integration of complex electronics within cardiac patches will eventually provide therapeutic control and regulation of cardiac function. PMID:26974408

  10. An electron microscope for the aberration-corrected era.

    PubMed

    Krivanek, O L; Corbin, G J; Dellby, N; Elston, B F; Keyse, R J; Murfitt, M F; Own, C S; Szilagyi, Z S; Woodruff, J W

    2008-02-01

    Improved resolution made possible by aberration correction has greatly increased the demands on the performance of all parts of high-end electron microscopes. In order to meet these demands, we have designed and built an entirely new scanning transmission electron microscope (STEM). The microscope includes a flexible illumination system that allows the properties of its probe to be changed on-the-fly, a third-generation aberration corrector which corrects all geometric aberrations up to fifth order, an ultra-responsive yet stable five-axis sample stage, and a flexible configuration of optimized detectors. The microscope features many innovations, such as a modular column assembled from building blocks that can be stacked in almost any order, in situ storage and cleaning facilities for up to five samples, computer-controlled loading of samples into the column, and self-diagnosing electronics. The microscope construction is described, and examples of its capabilities are shown.

  11. Engineered hybrid cardiac patches with multifunctional electronics for online monitoring and regulation of tissue function.

    PubMed

    Feiner, Ron; Engel, Leeya; Fleischer, Sharon; Malki, Maayan; Gal, Idan; Shapira, Assaf; Shacham-Diamand, Yosi; Dvir, Tal

    2016-06-01

    In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells are seeded within three-dimensional porous scaffolds to create functional cardiac patches. However, current cardiac patches do not allow for online monitoring and reporting of engineered-tissue performance, and do not interfere to deliver signals for patch activation or to enable its integration with the host. Here, we report an engineered cardiac patch that integrates cardiac cells with flexible, freestanding electronics and a 3D nanocomposite scaffold. The patch exhibited robust electronic properties, enabling the recording of cellular electrical activities and the on-demand provision of electrical stimulation for synchronizing cell contraction. We also show that electroactive polymers containing biological factors can be deposited on designated electrodes to release drugs in the patch microenvironment on demand. We expect that the integration of complex electronics within cardiac patches will eventually provide therapeutic control and regulation of cardiac function.

  12. The Impact of Electronic Communication on Writing. ERIC Digest.

    ERIC Educational Resources Information Center

    Abdullah, Mardziah Hayati

    Noting that electronic communication places new demands on language that leads to interesting variations in written language use, this Digest summarizes insights gained from research on writing behavior and performance in the electronic age. It concludes that both the process and the content of writing are evolving in response to the increased use…

  13. Towards Real Information on Demand.

    ERIC Educational Resources Information Center

    Barker, Philip

    The phrase "information on demand" is often used to describe situations in which digital electronic information can be delivered to particular points of need at times and in ways that are determined by the specific requirements of individual consumers or client groups. The advent of "mobile" computing equipment now makes the…

  14. 77 FR 4574 - Notice of Proposed Information Collection: Comment Request; Production of Material or Provision...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-30

    ... to Demands in Legal Proceedings Among Private Litigants AGENCY: Office of the General Counsel, HUD... forms of information technology, e.g., permitting electronic submission of responses. This Notice also... Response to Demands in Legal Proceedings Among Private Litigants. OMB Control Number, if applicable: 2501...

  15. News of the Year.

    ERIC Educational Resources Information Center

    Albanese, Andrew R.; Oder, Norman; Rogers, Michael; St. Lifer, Evan; Jay, M. Ellen; Milliot, Jim

    2001-01-01

    Includes three articles that discuss the top stories from "Library Journal", including the demand for librarians, the Digital Millennium Copyright Act, library education, database publishers, electronic research services, the Uniform Computer Information Transactions Act (UCITA), Internet filtering, and electronic reference; the school…

  16. BIOREMEDIATION AT WOOD-PRESERVING SITES

    EPA Science Inventory

    The removal of organic compounds from ground water during bioremediation at wood-preserving sites is a function of the stoichiometric demand for electron acceptors (oxygen, nitrate, and sulfate) to metabolize the organic contaminants and the supply of the electron acceptors in th...

  17. Institutional Challenges to Increased Library Provision of Electronic Materials

    ERIC Educational Resources Information Center

    Johnson, Gareth J.

    2007-01-01

    The University of York is among the top universities in the United Kingdom, yet has not adopted all manner of electronic media. The University Library attempts to meet the demands placed upon it by its academic and student users for electronic media of all kinds, while working within a sometimes frame work that does not encourage exploitation of…

  18. A Electronic Map Data Model Based on PDF

    NASA Astrophysics Data System (ADS)

    Zhou, Xiaodong; Yang, Chuncheng; Meng, Nina; Peng, Peng

    2018-05-01

    In this paper, we proposed the PDFEMAP (PDF electronic map) that is a kind of new electronic map products aiming at the current situation and demand of the use of electronic map products. Firstly gives the definition and characteristics of PDFEMAP, followed by a detailed description of the data model and method for generating PDFEMAP, and finally expounds application modes of the PDFEMAP which feasibility and effectiveness are verified.

  19. Virtual Seminars and Their Impact on the Role of the Teaching Staff.

    ERIC Educational Resources Information Center

    Jelfs, Anne; Colbourn, Chris

    2002-01-01

    Discusses current demands on teaching staff in United Kingdom higher education and the impact these demands have when teaching through electronic resources. Topics include collaborative small-group learning; transferable skills; nontraditional students; the role of the tutor; social theories of education; and a case study of virtual seminars for…

  20. How Do We Afflict the Comfortable--When They Own Us?

    ERIC Educational Resources Information Center

    Bugeja, Michel

    2005-01-01

    Media and news companies strive to keep costs down while maximizing profit through electronic news and information dissemination and engaging in unethical personnel managing practices. The author argues that journalism teachers and schools have catered to the demands of media companies by concentrating only on skills demanded by the industry. It…

  1. 78 FR 12792 - Agency Information Collection Activities; Proposed Collection; Comments Requested: Report of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-25

    ... Transactions--Demand 2 ACTION: 30-Day Notice. The Department of Justice (DOJ), Bureau of Alcohol, Tobacco... forms of information technology, e.g., permitting electronic submission of responses. Summary of...) Title of the Form/Collection: Report of Firearms Transactions-- Demand 2. (3) Form Number: ATF F 5300.5...

  2. Biochemical Oxygen Demand and Dissolved Oxygen. Training Module 5.105.2.77.

    ERIC Educational Resources Information Center

    Kirkwood Community Coll., Cedar Rapids, IA.

    This document is an instructional module package prepared in objective form for use by an instructor familiar with the azide modification of the Winkler dissolved oxygen test and the electronic dissolved oxygen meter test procedures for determining the dissolved oxygen and the biochemical oxygen demand of a wastewater sample. Included are…

  3. Substitutability of nicotine alone and an electronic cigarette liquid using a concurrent choice assay in rats: A behavioral economic analysis.

    PubMed

    Smethells, John R; Harris, Andrew C; Burroughs, Danielle; Hursh, Steven R; LeSage, Mark G

    2018-04-01

    For the Food and Drug Administration to effectively regulate tobacco products, the contribution of non-nicotine tobacco constituents to the abuse liability of tobacco must be well understood. Our previous work compared the abuse liability of electronic cigarette refill liquids (EC liquids) and nicotine (Nic) alone when each was available in isolation and found no difference in abuse liability (i.e., demand elasticity). Another, and potentially more sensitive measure, would be to examine abuse liability in a choice context, which also provides a better model of the tobacco marketplace. Demand elasticity for Nic alone and an EC liquid were measured when only one formulation was available (alone-price demand) and when both formulations were concurrently available (own-price demand), allowing an assessment of the degree to which each formulation served as a substitute (cross-price demand) when available at a low fixed-price. Own-price demand for both formulations were more elastic compared to alone-price demand, indicating that availability of a substitute increased demand elasticity. During concurrent access, consumption of the fixed-price formulation increased as the unit-price of the other formulation increased. The rate of increase was similar between formulations, indicating that they served as symmetrical substitutes. The cross-price model reliably quantified the substitutability of both nicotine formulations and indicated that the direct CNS effects of non-nicotine constituents in EC liquid did not alter its abuse liability compared to Nic. These data highlight the sensitivity of this model and its potential utility for examining the relative abuse liability and substitutability of tobacco products. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Recent advancements towards green optical networks

    NASA Astrophysics Data System (ADS)

    Davidson, Alan; Glesk, Ivan; Buis, Adrianus; Wang, Junjia; Chen, Lawrence

    2014-12-01

    Recent years have seen a rapid growth in demand for ultra high speed data transmission with end users expecting fast, high bandwidth network access. With this rapid growth in demand, data centres are under pressure to provide ever increasing data rates through their networks and at the same time improve the quality of data handling in terms of reduced latency, increased scalability and improved channel speed for users. However as data rates increase, present technology based on well-established CMOS technology is becoming increasingly difficult to scale and consequently data networks are struggling to satisfy current network demand. In this paper the interrelated issues of electronic scalability, power consumption, limited copper interconnect bandwidth and the limited speed of CMOS electronics will be explored alongside the tremendous bandwidth potential of optical fibre based photonic networks. Some applications of photonics to help alleviate the speed and latency in data networks will be discussed.

  5. "Emmerce" Immersion: The Emerging World of Electronic Commerce.

    ERIC Educational Resources Information Center

    Chuck, Lysbeth

    1997-01-01

    Discusses the effects of Web-based electronic commerce, or "emmerce," on online user. Defines "cookies" and Persistent Client State HTTP Cookies or "magic cookies" on Macintosh computers. Examines underlying technologies that make up "cashless" transactions; growing demand for micropayments; CyberCash,…

  6. Remodelling Marketing Communications in an Internet Environment.

    ERIC Educational Resources Information Center

    Rowley, Jennifer

    2001-01-01

    Argues that the Internet demands a significant review of approaches to marketing communications, or promotion, as both the strategic and tactical levels. Highlights include electronic business and electronic commerce; comparing organizational and consumer markets; service development; objectives of marketing communications; and questions for…

  7. The Development of Electronic Educational Environment of the Contemporary Higher Educational Institution within the Context of Teaching Innovations

    ERIC Educational Resources Information Center

    Khairova, Irina V.; Toktarova, Vera I.

    2016-01-01

    The problem under study is acute due to rampant development of electronic education putting forward new demands to the arrangement of professional education of HEI students. The article makes a review of innovative means and technologies contributing to the perfection of instructional design of new-generation electronic educational environment.…

  8. School Superintendents' Use of Electronic Communication Technology and Its Impact on Their Efficacy as a School District Leader

    ERIC Educational Resources Information Center

    Brock, Cecilia

    2017-01-01

    As apex leaders, school superintendents are impacted by the continuous demand to be effective while utilizing electronic communication technology. The purpose of this study is to investigate how the use of electronic communication technology impacts a school superintendent's efficacy. Public education, in the twenty-first century, finds itself in…

  9. Electronic switches and control circuits: A compilation

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The innovations in this updated series of compilations dealing with electronic technology represents a carefully selected collection of items on electronic switches and control circuits. Most of the items are based on well-known circuit design concepts that have been simplified or refined to meet NASA's demanding requirement for reliability, simplicity, fail-safe characteristics, and the capability of withstanding environmental extremes.

  10. Microcontact Printing Patterning of an HOPG Surface by an Inverse Electron Demand Diels-Alder Reaction.

    PubMed

    Zhu, Jun; Hiltz, Jonathan; Tefashe, Ushula M; Mauzeroll, Janine; Lennox, R Bruce

    2018-06-21

    The chemical modification of an sp 2 hybridized carbon surface in a controllable manner is very challenging but also crucial for many applications. An inverse electron demand Diels-Alder (IEDDA) reaction using microcontact printing technique is introduced to spatially control the modification of a highly ordered pyrolytic graphite (HOPG) surface under ambient conditions. The covalent modification was characterized by Raman spectroscopy, XPS, and SECM. Tetrazine derivatives can effectively react with an HOPG surface and with microcontact printing methods resulting in spatially patterned surfaces being produced with micrometer-scale resolution. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Response surface modeling for optimization heterocatalytic Fenton oxidation of persistence organic pollution in high total dissolved solid containing wastewater.

    PubMed

    Sekaran, G; Karthikeyan, S; Boopathy, R; Maharaja, P; Gupta, V K; Anandan, C

    2014-01-01

    The rice-husk-based mesoporous activated carbon (MAC) used in this study was precarbonized and activated using phosphoric acid. N2 adsorption/desorption isotherm, X-ray powder diffraction, electron spin resonance, X-ray photoelectron spectroscopy and scanning electron microscopy, transmission electron microscopy, (29)Si-NMR spectroscopy, and diffuse reflectance spectroscopy were used to characterize the MAC. The tannery wastewater carrying high total dissolved solids (TDS) discharged from leather industry lacks biodegradability despite the presence of dissolved protein. This paper demonstrates the application of free electron-rich MAC as heterogeneous catalyst along with Fenton reagent for the oxidation of persistence organic compounds in high TDS wastewater. The heterogeneous Fenton oxidation of the pretreated wastewater at optimum pH (3.5), H2O2 (4 mmol/L), FeSO4[Symbol: see text]7H2O (0.2 mmol/L), and time (4 h) removed chemical oxygen demand, biochemical oxygen demand, total organic carbon and dissolved protein by 86, 91, 83, and 90%, respectively.

  12. Building Self-Discipline to Promote Learning: Students' Volitional Strategies to Navigate the Demands of Schooling

    ERIC Educational Resources Information Center

    Elstad, Eyvind

    2008-01-01

    Volitional issues are important in today's classrooms where autonomous students are expected to manage school demands on their own. A new kind of challenge has appeared with the advent of free Internet access in the classroom. Motivational conflicts may therefore arise between (1) immediate rewards of electronic chatting, surfing, and games and…

  13. Global demand for rare earth resources and strategies for green mining

    USDA-ARS?s Scientific Manuscript database

    Rare earths elements (REEs) are essential raw materials for the emerging green (low-carbon) energy technologies and ‘smart’ electronic devices. Global REE demand is slated to grow at a compound annual rate of 5% by 2020. Such high growth rate would require a steady supply base of REEs in the long ru...

  14. 77 FR 22798 - Submission of Proposed Information Collection to OMB: Production of Material or Provisions of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ... Information Collection to OMB: Production of Material or Provisions of Testimony by HUD in Response to Demands....203 of HUD's regulations in 24 CFR specify the manner in which demands for documents and testimony... forms of information technology, e.g., permitting electronic submission of responses. This notice also...

  15. 77 FR 20647 - Notice of Submission of Proposed Information Collection to OMB; Public Access to HUD Records...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-05

    .... Section 15.203 of HUD's regulations in 24 CFR specify the manner in which demands for documents and... forms of information technology, e.g., permitting electronic submission of responses. This notice also...: Section 15.203 of HUD's regulations in 24 CFR specify the manner in which demands for documents and...

  16. Developing Health Information Technology (HIT) Programs and HIT Curriculum: The Southern Polytechnic State University Experience

    ERIC Educational Resources Information Center

    Zhang, Chi; Reichgelt, Han; Rutherfoord, Rebecca H.; Wang, Andy Ju An

    2014-01-01

    Health Information Technology (HIT) professionals are in increasing demand as healthcare providers need help in the adoption and meaningful use of Electronic Health Record (EHR) systems while the HIT industry needs workforce skilled in HIT and EHR development. To respond to this increasing demand, the School of Computing and Software Engineering…

  17. Information Transfer in 1990.

    ERIC Educational Resources Information Center

    Hough, Roger W.

    Results of a recent study of potential demand for electronic information transfer services in 1970-1990 are presented. Projections are made for new services such as electronic mail, remote library browsing, checkless society transactions, video telephone and others, as well as conventional services such as telephone, telegraph and network program…

  18. Principled Libraries: Finding Stability in Changing Times.

    ERIC Educational Resources Information Center

    Crawford, Walt

    2000-01-01

    Discusses the transition that libraries are currently experiencing between physical resources and electronic access. Topics include technology as tools rather than solutions; media and technology; desktop publishing; electronic books; Web commerce; instant books, or books printed on demand; new types of media; and serving the users. (LRW)

  19. Electronic Books: Towards a Theoretical Framework for Research.

    ERIC Educational Resources Information Center

    Yeaman, Andrew R. J.

    In an increasingly technological society, there is a social need for designing communication technology around the perceptual abilities and cognitive strategies of people. A growing demand for information has created additional pressure on emerging communication technologies to provide electronic alternatives to the printed page. Design depends…

  20. Heuristic for Learning Common Emitter Amplification with Bipolar Transistors

    ERIC Educational Resources Information Center

    Staffas, Kjell

    2017-01-01

    Mathematics in engineering education causes many thresholds in the courses because of the demand of abstract conceptualisation. Electronics depend heavily on more or less complex mathematics. Therefore the concepts of analogue electronics are hard to learn since a great deal of students struggle with the calculations and procedures needed. A…

  1. Electronic Books: A Major Publishing Revolution. Part 1: General Considerations and Issues.

    ERIC Educational Resources Information Center

    Hawkins, Donald T.

    2000-01-01

    Discusses electronic books and their impact on the publishing industry. Topics include a history of the book industry; downloadable ebooks; dedicated ebook readers; Web-accessible ebooks; print-on-demand books; advantages and disadvantages; copyright; ebook concerns in libraries, including licensing, lack of standards, bibliographic control, and…

  2. Electronic ferroelectricity in carbon-based systems: from reality of organic conductors to promises of polymers and graphene nano-ribbons

    NASA Astrophysics Data System (ADS)

    Kirova, Natasha; Brazovskii, Serguei

    2014-03-01

    Ferroelectricity is a rising demand in fundamental and applied solid state physics. Ferroelectrics are used in microelectronics as active gate materials, in capacitors, electro-optical-acoustic modulators, etc. There is a particular demand for plastic ferroelectrics, e.g. as a sensor for acoustic imaging in medicine and beyond, in shapeable capacitors, etc. Microscopic mechanisms of ferroelectric polarization in traditional materials are typically ionic. In this talk we discuss the electronic ferroelectrics - carbon-based materials: organic crystals, conducting polymers and graphene nano-ribbons. The motion of walls, separating domains with opposite electric polarisation, can be influenced and manipulated by terahertz and infra-red range optics.

  3. Cognitive task demands, self-control demands and the mental well-being of office workers.

    PubMed

    Bridger, Robert S; Brasher, Kate

    2011-09-01

    The cognitive task demands of office workers and the self-control demands of their work roles were measured in a sample of 196 employees in two different office layouts using a self-report questionnaire, which was circulated electronically. Multiple linear regression analysis revealed that both factors were associated with mental well-being, but not with physical well-being, while controlling for exposure to psychosocial stressors. The interaction between cognitive task demands and self-control demands had the strongest association with mental well-being, suggesting that the deleterious effect of one was greater when the other was present. An exploratory analysis revealed that the association was stronger for employees working in a large open-plan office than for those working in smaller offices with more privacy. Frustration of work goals was the cognitive task demand having the strongest negative impact on mental well-being. Methodological limitations and scale psychometrics (particularly the use of the NASA Task Load Index) are discussed. STATEMENT OF RELEVANCE: Modern office work has high mental demands and low physical demands and there is a need to design offices to prevent adverse psychological reactions. It is shown that cognitive task demands interact with self-control demands to degrade mental well-being. The association was stronger in an open-plan office.

  4. Industry Driven Electronic Communication Competencies for an Associate Electronics Degree: A Phenomenological Study

    ERIC Educational Resources Information Center

    McNeill, Dennis G.

    2013-01-01

    Scholars and professionals alike contend our nation's competitive position and economic growth depends considerably on the acumen of its science, technology, engineering, and math (STEM) talent pool. In spite of current economic conditions and high national unemployment, there is an increasing demand for those skilled in technology and…

  5. Understanding Clinician Information Demands and Synthesis of Clinical Documents in Electronic Health Record Systems

    ERIC Educational Resources Information Center

    Farri, Oladimeji Feyisetan

    2012-01-01

    Large quantities of redundant clinical data are usually transferred from one clinical document to another, making the review of such documents cognitively burdensome and potentially error-prone. Inadequate designs of electronic health record (EHR) clinical document user interfaces probably contribute to the difficulties clinicians experience while…

  6. E-Learning System for Experiments Involving Construction of Practical Electronic Circuits

    ERIC Educational Resources Information Center

    Takemura, Atsushi

    2013-01-01

    This paper proposes a novel e-learning system for technical experiments involving the construction of practical electronic circuits; this system would meet the various demands of individual experimenters. This mixed mode is beneficial for practical use in that an experimenter who does not have sufficient circuit components for circuit making can…

  7. The Interplay of Surface Mount Solder Joint Quality and Reliability of Low Volume SMAs

    NASA Technical Reports Server (NTRS)

    Ghaffarian, R.

    1997-01-01

    Spacecraft electronics including those used at the Jet Propulsion Laboratory (JPL), demand production of highly reliable assemblies. JPL has recently completed an extensive study, funded by NASA's code Q, of the interplay between manufacturing defects and reliability of ball grid array (BGA) and surface mount electronic components.

  8. Supply and demand of some critical metals and present status of their recycling in WEEE.

    PubMed

    Zhang, Shengen; Ding, Yunji; Liu, Bo; Chang, Chein-Chi

    2017-07-01

    New development and technological innovations make electrical and electronic equipment (EEE) more functional by using an increasing number of metals, particularly the critical metals (e.g. rare and precious metals) with specialized properties. As millions of people in emerging economies adopt a modern lifestyle, the demand for critical metals is soaring. However, the increasing demand causes the crisis of their supply because of their simple deficiency in the Earth's crust or geopolitical constraints which might create political issues for their supply. This paper focuses on the sustainable supply of typical critical metals (indium, rare earth elements (REEs), lithium, cobalt and precious metals) through recycling waste electrical and electronic equipment (WEEE). To illuminate this issue, the production, consumption, expected future demand, current recycling situation of critical metals, WEEE management and their recycling have been reviewed. We find that the demand of indium, REEs, lithium and cobalt in EEE will continuously increasing, while precious metals are decreasing because of new substitutions with less or even without precious metals. Although the generation of WEEE in 2014 was about 41.9 million tons (Mt), just about 15% (6.5 Mt) was treated environmentally. The inefficient collection of WEEE is the main obstacle to relieving the supply risk of critical metals. Furthermore, due to the widespread use in low concentrations, such as indium, their recycling is not just technological problem, but economic feasibility is. Finally, relevant recommendations are point out to address these issues. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Energy storage apparatus

    NASA Technical Reports Server (NTRS)

    Studer, P. A.; Evans, H. E. (Inventor)

    1978-01-01

    A high efficiency, flywheel type energy storage device which comprises an electronically commutated d.c. motor/generator unit having a massive flywheel rotor magnetically suspended around a ring shaped stator is presented. During periods of low energy demand, the storage devices were operated as a motor, and the flywheel motor was brought up to operating speed. Energy was drawn from the device functioning as a generator as the flywheel rotor rotated during high energy demand periods.

  10. Towards green high capacity optical networks

    NASA Astrophysics Data System (ADS)

    Glesk, I.; Mohd Warip, M. N.; Idris, S. K.; Osadola, T. B.; Andonovic, I.

    2011-09-01

    The demand for fast, secure, energy efficient high capacity networks is growing. It is fuelled by transmission bandwidth needs which will support among other things the rapid penetration of multimedia applications empowering smart consumer electronics and E-businesses. All the above trigger unparallel needs for networking solutions which must offer not only high-speed low-cost "on demand" mobile connectivity but should be ecologically friendly and have low carbon footprint. The first answer to address the bandwidth needs was deployment of fibre optic technologies into transport networks. After this it became quickly obvious that the inferior electronic bandwidth (if compared to optical fiber) will further keep its upper hand on maximum implementable serial data rates. A new solution was found by introducing parallelism into data transport in the form of Wavelength Division Multiplexing (WDM) which has helped dramatically to improve aggregate throughput of optical networks. However with these advancements a new bottleneck has emerged at fibre endpoints where data routers must process the incoming and outgoing traffic. Here, even with the massive and power hungry electronic parallelism routers today (still relying upon bandwidth limiting electronics) do not offer needed processing speeds networks demands. In this paper we will discuss some novel unconventional approaches to address network scalability leading to energy savings via advance optical signal processing. We will also investigate energy savings based on advanced network management through nodes hibernation proposed for Optical IP networks. The hibernation reduces the network overall power consumption by forming virtual network reconfigurations through selective nodes groupings and by links segmentations and partitionings.

  11. The Scoring of Matching Questions Tests: A Closer Look

    ERIC Educational Resources Information Center

    Jancarík, Antonín; Kostelecká, Yvona

    2015-01-01

    Electronic testing has become a regular part of online courses. Most learning management systems offer a wide range of tools that can be used in electronic tests. With respect to time demands, the most efficient tools are those that allow automatic assessment. The presented paper focuses on one of these tools: matching questions in which one…

  12. Investigation of Electronic Generation of Visual Images for Air Force Technical Training. Interim Report for Period May 1974-October 1975.

    ERIC Educational Resources Information Center

    Filinger, Ronald H.; Hall, Paul W.

    Because large scale individualized learning systems place excessive demands on conventional means of producing audiovisual software, electronic image generation has been investigated as an alternative. A prototype, experimental device, Scanimate-500, was designed and built by the Computer Image Corporation. It uses photographic, television, and…

  13. Air Force Manufacturing Technology. Year 2000 Project Book

    DTIC Science & Technology

    2000-01-01

    Electronic Warfare Component Manufacturing 13 National Center for Manufacturing Science 14 Product Research Market Analysis System 15 Electronics Acoustic...other agile organizations that can respond to rapidly changing market demands. Approach This program demonstrated and evaluated the advanced design...production worker contact with customers and suppliers; shopfloor identification of new technologies, markets , and products; and strategic planning to assure

  14. A comprehensive examination of own- and cross-price elasticities of tobacco and nicotine replacement products in the U.S.

    PubMed

    Huang, Jidong; Gwarnicki, Cezary; Xu, Xin; Caraballo, Ralph S; Wada, Roy; Chaloupka, Frank J

    2018-04-21

    While much is known about the demand for cigarettes, research on the demand for non-cigarette tobacco products and the cross-price impacts among those products is limited. This study aims to comprehensively examine the own- and cross-price elasticities of demand for tobacco and nicotine replacement products (NRPs) in the U.S. We analyzed market-level quarterly data on sales and prices of 15 different types of tobacco products and NRPs from 2007 to 2014, compiled from retail store scanner data. Fixed effects models with controls were used to estimate their own-price elasticities and cross-price elasticities between cigarettes and the other 14 products. Our results show that, except for cigars, the demand for combustible tobacco products was generally elastic, with the estimated own-price elasticity >1 (10% increase in prices reduces sales by >10%). The own-price elasticities for smokeless tobacco products were smaller than those for combustible tobacco, although not always significant. The demand for electronic cigarettes and NRPs was found to be elastic. The cross-price elasticities with respect to cigarettes were positive for cigarillos, little cigars, loose tobacco, pipe tobacco, electronic cigarettes and NRPs, but only results for little cigars, loose tobacco, pipe tobacco, and dissolvable lozenges were consistently significant. Our findings suggest demand for tobacco products and NRPs was responsive to changes in their own prices. Substitutions or positive cross-price impacts between cigarettes and certain other products exist. It is important that tobacco control policies take into account both own- and cross-price impacts among tobacco products and NRTs. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Demand management: an audit of chemical pathology test rejections by an electronic gate-keeping system at an academic hospital in Cape Town.

    PubMed

    Smit, Ida; Zemlin, Annalise E; Erasmus, Rajiv T

    2015-07-01

    Demand management is an area of laboratory activity, which is becoming increasingly important. Within the health-care system, demand management can be defined as the use of health resources to maximise its utility. Tygerberg Hospital has introduced an electronic gate-keeping system. Chemistry tests which generate the highest cost are subjected to this system and may be automatically rejected according to a set of rules. This study aimed: (1) to identify the number of chemistry tests rejected by the eGK; (2) to identify which of these rejected tests were subsequently restored and (3) to assess the impact of rejections on clinical outcome and cost-saving. A retrospective audit was conducted to determine the number of chemistry tests rejected and subsequently restored over a 6-month period. The case-notes of patients for whom requested tests previously rejected had been restored were randomly selected and investigated to assess clinical impact. Any cost-saving was calculated. A total of 68,480 tests were subjected to gate-keeping, and 4605 tests (6.7%) were rejected while 679 (14.7%) of these were restored by the requestor phoning the laboratory after obtaining authorisation. After examining a subset of clinical notes it was found that in most cases (80%), patient care was unaffected. The total cost saved was £ 25,387. The majority of the rejected tests were unnecessary and following rejection, real savings were made. Electronic gate-keeping is a simple, effective and sustainable method of demand management. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  16. 75 FR 70031 - Antitrust Division

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ...) operate a branding program based upon distinctive trademarks to create high customer awareness of, demand... or subcontract a branding program; (vii) create printed and/or electronic materials for distribution...

  17. ISLE: Intelligent Selection of Loop Electronics. A CLIPS/C++/INGRES integrated application

    NASA Technical Reports Server (NTRS)

    Fischer, Lynn; Cary, Judson; Currie, Andrew

    1990-01-01

    The Intelligent Selection of Loop Electronics (ISLE) system is an integrated knowledge-based system that is used to configure, evaluate, and rank possible network carrier equipment known as Digital Loop Carrier (DLC), which will be used to meet the demands of forecasted telephone services. Determining the best carrier systems and carrier architectures, while minimizing the cost, meeting corporate policies and addressing area service demands, has become a formidable task. Network planners and engineers use the ISLE system to assist them in this task of selecting and configuring the appropriate loop electronics equipment for future telephone services. The ISLE application is an integrated system consisting of a knowledge base, implemented in CLIPS (a planner application), C++, and an object database created from existing INGRES database information. The embedibility, performance, and portability of CLIPS provided us with a tool with which to capture, clarify, and refine corporate knowledge and distribute this knowledge within a larger functional system to network planners and engineers throughout U S WEST.

  18. {open_quotes}Media-On-Demand{close_quotes} multimedia electronic mail: A tool for collaboration on the web

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsoi, Kei Nam; Rahman, S.M.

    1996-12-31

    Undoubtedly, multimedia electronic mail has many advantages in exchanging information electronically in a collaborative work. The existing design of e-mail systems architecture is inefficient in exchanging multimedia message which has much larger volume, and requires more bandwidth and storage space than the text-only messages. This paper presents an innovative method for exchanging multimedia mail messages in a heterogeneous environment to support collaborative work over YAW on the Internet. We propose a {open_quotes}Parcel Collection{close_quotes} approach for exchanging multimedia electronic mail messages. This approach for exchanging multimedia electronic mail messages integrates the current WWW technologies with the existing electronic mail systems.

  19. ent-Kaurane-Based Regio- and Stereoselective Inverse Electron Demand Hetero-Diels-Alder Reactions: Synthesis of Dihydropyran-Fused Diterpenoids†

    PubMed Central

    Ding, Chunyong; Wang, Lili; Chen, Haijun; Wild, Christopher; Ye, Na; Ding, Ye; Wang, Tianzhi; White, Mark A.; Shen, Qiang; Zhou, Jia

    2014-01-01

    A mild and concise approach for the construction of 3,4-dihydro-2H-pyran ring integrated into the A-ring of the natural product oridonin using an optimized inverse electron demand hetero-Diels-Alder (IED HDA) reaction is reported herein. A self-dimerization of the exocyclic enone installed in the A-ring through a homo-HDA reaction was identified to exclusively give a dimeric ent-kaurane diterpenoid with the spirochroman core. Moreover, the efficient cross-HDA cycloadditions of this enone with various vinyl ethers or vinyl sulfides, instead of its own homo-HDA dimerization, were achieved in regio- and stereoselective manners, thus providing the access to novel dihydropyran-fused diterpenoids as potential anticancer agents to overcome chemoresistance. PMID:25225052

  20. Intramolecular inverse-electron-demand Diels-Alder reactions of imidazoles with 1,2,4-triazines: a new route to 1,2,3,4-tetrahydro-1,5-naphthyridines and related heterocycles.

    PubMed

    Lahue, Brian R; Lo, Sie-Mun; Wan, Zhao-Kui; Woo, Grace H C; Snyder, John K

    2004-10-15

    The intramolecular inverse-electron-demand Diels-Alder reaction between imidazoles and 1,2,4-triazines linked by a trimethylene tether from the imidazole N1 position to the triazine C3 proceed in excellent yields to produce 1,2,3,4-tetrahydro-1,5-naphthyridines. The reaction proceeds by a cycloaddition with subsequent loss of nitrogen, followed by a presumed stepwise loss of a nitrile. The analogous intramolecular cycloadditions employing a tetramethylene tether also proceeded to give 2,3,4,5-tetrahydro-1H-pyrido[3,2-b]azepines in acceptable yields. The reaction to produce the tetrahydro-1,5-naphthyridines can also be promoted with microwave irradiation.

  1. E-Communications 101: Here Is Your Guide to Efficient Communication in an Electronic Age

    ERIC Educational Resources Information Center

    Solomon, Gwen

    2004-01-01

    More tasks than ever are heading online these days--from student projects and field trips to virtual schools and electronic professional development. The big idea is that technology saves time and effort, focuses people quickly and easily, and commands attention in a world of too many demands, distractions, and delivery systems. So what are the…

  2. The journey from forensic to predictive materials science using density functional theory

    DOE PAGES

    Schultz, Peter A.

    2017-09-12

    Approximate methods for electronic structure, implemented in sophisticated computer codes and married to ever-more powerful computing platforms, have become invaluable in chemistry and materials science. The maturing and consolidation of quantum chemistry codes since the 1980s, based upon explicitly correlated electronic wave functions, has made them a staple of modern molecular chemistry. Here, the impact of first principles electronic structure in physics and materials science had lagged owing to the extra formal and computational demands of bulk calculations.

  3. The journey from forensic to predictive materials science using density functional theory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schultz, Peter A.

    Approximate methods for electronic structure, implemented in sophisticated computer codes and married to ever-more powerful computing platforms, have become invaluable in chemistry and materials science. The maturing and consolidation of quantum chemistry codes since the 1980s, based upon explicitly correlated electronic wave functions, has made them a staple of modern molecular chemistry. Here, the impact of first principles electronic structure in physics and materials science had lagged owing to the extra formal and computational demands of bulk calculations.

  4. A voltammetric electronic tongue as tool for water quality monitoring in wastewater treatment plants.

    PubMed

    Campos, Inmaculada; Alcañiz, Miguel; Aguado, Daniel; Barat, Ramón; Ferrer, José; Gil, Luis; Marrakchi, Mouna; Martínez-Mañez, Ramón; Soto, Juan; Vivancos, José-Luis

    2012-05-15

    The use of a voltammetric electronic tongue as tool for the prediction of concentration levels of certain water quality parameters from influent and effluent wastewater from a Submerged Anaerobic Membrane Bioreactor pilot plant applied to domestic wastewater treatment is proposed here. The electronic tongue consists of a set of noble (Au, Pt, Rh, Ir, and Ag) and non-noble (Ni, Co and Cu) electrodes that were housed inside a stainless steel cylinder which was used as the body of the electronic tongue system. As a previous step an electrochemical study of the response of the ions sulphate, orthophosphate, acetate, bicarbonate and ammonium was carried out in water using the electrodes contained in the electronic tongue. The second part of the work was devoted to the application of the electronic tongue to the characterization of the influent and effluent waters from the wastewater treatment plant. Partial Least Squares analysis was used to obtain a correlation between the data from the tongue and the pollution parameters measured in the laboratory such as soluble chemical oxygen demand (CODs), soluble biological oxygen demand (BODs), ammonia (NH(4)-N), orthophosphate (PO(4)-P), Sulphate (SO(4)-S), acetic acid (HAC) and alkalinity (Alk). A total of 28 and 11 samples were used in the training and the validation steps, respectively, for both influent and effluent water samples. The electronic tongue showed relatively good predictive power for the determination of BOD, COD, NH(4)-N, PO(4)-P, SO(4)-S, and Alk. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Practical 3D Printing of Antennas and RF Electronics

    DTIC Science & Technology

    2017-03-01

    Passive RF; Combiners Introduction Additive manufacturing can reduce the time and material costs in a design cycle and enable the on-demand printing of...performance, and create Computer Assisted Manufacturing (CAM) files. By intelligently leveraging this process, the design can be readily updated or...advances in 3D printing technology now enable antennas and RF electronics to be designed and prototyped significantly faster than conventional

  6. Electron Waiting Times of a Cooper Pair Splitter

    NASA Astrophysics Data System (ADS)

    Walldorf, Nicklas; Padurariu, Ciprian; Jauho, Antti-Pekka; Flindt, Christian

    2018-02-01

    Electron waiting times are an important concept in the analysis of quantum transport in nanoscale conductors. Here we show that the statistics of electron waiting times can be used to characterize Cooper pair splitters that create spatially separated spin-entangled electrons. A short waiting time between electrons tunneling into different leads is associated with the fast emission of a split Cooper pair, while long waiting times are governed by the slow injection of Cooper pairs from a superconductor. Experimentally, the waiting time distributions can be measured using real-time single-electron detectors in the regime of slow tunneling, where conventional current measurements are demanding. Our work is important for understanding the fundamental transport processes in Cooper pair splitters and the predictions may be verified using current technology.

  7. U.S. Demand for Tobacco Products in a System Framework.

    PubMed

    Zheng, Yuqing; Zhen, Chen; Dench, Daniel; Nonnemaker, James M

    2017-08-01

    This study estimated a system of demand for cigarettes, little cigars/cigarillos, large cigars, e-cigarettes, smokeless tobacco, and loose smoking tobacco using market-level scanner data for convenience stores. We found that the unconditional own-price elasticities for the six categories are -1.188, -1.428, -1.501, -2.054, -0.532, and -1.678, respectively. Several price substitute (e.g., cigarettes and e-cigarettes) and complement (e.g., cigarettes and smokeless tobacco) relationships were identified. Magazine and television advertising increased demand for e-cigarettes, and magazine advertising increased demand for smokeless tobacco and had spillover effects on demand for other tobacco products. We also reported the elasticities by U.S. census regions and market size. These results may have important policy implications, especially viewed in the context of the rise of electronic cigarettes and the potential for harm reduction if combustible tobacco users switch to non-combustible tobacco products. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. 77 FR 50243 - Electronic Fund Transfers (Regulation E)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-20

    ... transfers. DATES: This rule is effective February 7, 2013. FOR FURTHER INFORMATION CONTACT: Eric Goldberg... variation in the demand for remittance transfers, the Bureau believes that an annual figure is the most...

  9. Job Prospects for E/E Engineers.

    ERIC Educational Resources Information Center

    Basta, Nicholas

    1985-01-01

    Despite slack in some computer companies, overall demand for new electrical and electronic graduates continues to be strong. Employment potential also exists in such areas as government, manufacturing, utilities, and defense (especially aerospace industries). (DH)

  10. Optical Computers and Space Technology

    NASA Technical Reports Server (NTRS)

    Abdeldayem, Hossin A.; Frazier, Donald O.; Penn, Benjamin; Paley, Mark S.; Witherow, William K.; Banks, Curtis; Hicks, Rosilen; Shields, Angela

    1995-01-01

    The rapidly increasing demand for greater speed and efficiency on the information superhighway requires significant improvements over conventional electronic logic circuits. Optical interconnections and optical integrated circuits are strong candidates to provide the way out of the extreme limitations imposed on the growth of speed and complexity of nowadays computations by the conventional electronic logic circuits. The new optical technology has increased the demand for high quality optical materials. NASA's recent involvement in processing optical materials in space has demonstrated that a new and unique class of high quality optical materials are processible in a microgravity environment. Microgravity processing can induce improved orders in these materials and could have a significant impact on the development of optical computers. We will discuss NASA's role in processing these materials and report on some of the associated nonlinear optical properties which are quite useful for optical computers technology.

  11. (125)I-Tetrazines and Inverse-Electron-Demand Diels-Alder Chemistry: A Convenient Radioiodination Strategy for Biomolecule Labeling, Screening, and Biodistribution Studies.

    PubMed

    Albu, Silvia A; Al-Karmi, Salma A; Vito, Alyssa; Dzandzi, James P K; Zlitni, Aimen; Beckford-Vera, Denis; Blacker, Megan; Janzen, Nancy; Patel, Ramesh M; Capretta, Alfredo; Valliant, John F

    2016-01-20

    A convenient method to prepare radioiodinated tetrazines was developed, such that a bioorthogonal inverse electron demand Diels-Alder reaction can be used to label biomolecules with iodine-125 for in vitro screening and in vivo biodistribution studies. The tetrazine was prepared by employing a high-yielding oxidative halo destannylation reaction that concomitantly oxidized the dihydrotetrazine precursor. The product reacts quickly and efficiently with trans-cyclooctene derivatives. Utility was demonstrated through antibody and hormone labeling experiments and by evaluating products using standard analytical methods, in vitro assays, and quantitative biodistribution studies where the latter was performed in direct comparison to Bolton-Hunter and direct iodination methods. The approach described provides a convenient and advantageous alternative to conventional protein iodination methods that can expedite preclinical development and evaluation of biotherapeutics.

  12. The Rare Earth Collision: A Hit and Run on the Third Offset Strategy

    DTIC Science & Technology

    2017-03-29

    Department of the Interior, Mineral Commodity Summaries 2016, 135 3 demand for REE. Each megawatt of capacity for a wind turbine requires about 450 lbs...commercial electronics, as well as a 700% projected growth in the wind turbine industry in the next 25 years and the increase of other renewable energy...of REE, which means the U.S.’s smallest wind farm by power output requires over 13,000 lbs of REE.11 With the increased demand for personal and

  13. Micro-flow photosynthesis of new dienophiles for inverse-electron-demand Diels–Alder reactions. Potential applications for pretargeted in vivo PET imaging† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6sc02933g Click here for additional data file.

    PubMed Central

    Billaud, Emilie M. F.; Shahbazali, Elnaz; Ahamed, Muneer; Cleeren, Frederik; Noël, Timothy; Koole, Michel; Verbruggen, Alfons; Hessel, Volker

    2017-01-01

    Pretargeted PET imaging has emerged as an effective two-step in vivo approach that combines the superior affinity and selectivity of antibodies with the rapid pharmacokinetics and favorable dosimetry of smaller molecules radiolabeled with short-lived radionuclides. This approach can be based on the bioorthogonal inverse-electron-demand Diels–Alder (IEDDA) reaction between tetrazines and trans-cyclooctene (TCO) derivatives. We aimed to develop new [18F]TCO–dienophiles with high reactivity for IEDDA reactions, and favorable in vivo stability and pharmacokinetics. New dienophiles were synthesized using an innovative micro-flow photochemistry process, and their reaction kinetics with a tetrazine were determined. In vivo stability and biodistribution of the most promising 18F-radiolabeled-TCO-derivative ([18F]3) was investigated, and its potential for in vivo pretargeted PET imaging was assessed in tumor-bearing mice. We demonstrated that [18F]3 is a suitable dienophile for IEDDA reactions and for pretargeting applications. PMID:28451267

  14. Writing an Electronic Astronomy Book with Interactive Curricular Material

    NASA Astrophysics Data System (ADS)

    Thompson, Kristen L.; Belloni, Mario; Christian, Wolfgang

    2015-01-01

    With the rise of tablets, the past few years have seen an increase in the demand for quality electronic textbooks. Unfortunately, most of the current offerings do not exploit the accessibility and interactivity that electronic books can deliver. In this poster, we discuss how we are merging our curriculum development projects (Physlets, Easy Java/JavaScript Simulations, and Open Source Physics) with the EPUB electronic book format to develop an interactive textbook for use in a one-semester introductory astronomy course. The book, Astronomy: An Interactive Introduction, combines the narrative, equations, and images of a traditional astronomy text with new JavaScript simulations.

  15. Longitudinal bunch shaping of picosecond high-charge MeV electron beams

    DOE PAGES

    Beaudoin, B. L.; Thangaraj, J. C. T.; Edstrom, Jr., D.; ...

    2016-10-20

    With ever increasing demands for intensities in modern accelerators, the understanding of space-charge effects becomes crucial. Herein are presented measurements of optically shaped picosecond-long electron beams in a superconducting L-band linac over a wide range of charges, from 0.2 nC to 3.4 nC. At low charges, the shape of the electron beam is preserved, while at higher charge densities, modulations on the beam convert to energy modulations. Here, energy profile measurements using a spectrometer and time profile measurements using a streak camera reveal the dynamics of longitudinal space-charge on MeV-scale electron beams.

  16. The impact of price and tobacco control policies on the demand for electronic nicotine delivery systems

    PubMed Central

    Huang, Jidong; Tauras, John; Chaloupka, Frank J

    2014-01-01

    Background While much is known about the demand for conventional cigarettes, little is known about the determinants of demand for electronic nicotine delivery systems (ENDS or e-cigarettes). The goal of this study is to estimate the own and cross-price elasticity of demand for e-cigarettes and to examine the impact of cigarette prices and smoke-free policies on e-cigarette sales. Methods Quarterly e-cigarette prices and sales and conventional cigarette prices from 2009 to 2012 were constructed from commercial retail store scanner data from 52 US markets, for food, drug and mass stores, and from 25 markets, for convenience stores. Fixed-effects models were used to estimate the own and cross-price elasticity of demand for e-cigarettes and associations between e-cigarette sales and cigarette prices and smoke-free policies. Results Estimated own price elasticities for disposable e-cigarettes centred around −1.2, while those for reusable e-cigarettes were approximately −1.9. Disposable e-cigarette sales were higher in markets where reusable e-cigarette prices were higher and where less of the population was covered by a comprehensive smoke-free policy. There were no consistent and statistically significant relationships between cigarette prices and e-cigarette sales. Conclusions E-cigarette sales are very responsive to own price changes. Disposable e-cigarettes appear to be substitutes for reusable e-cigarettes. Policies increasing e-cigarette retail prices, such as limiting rebates, discounts and coupons and imposing a tax on e-cigarettes, could potentially lead to significant reductions in e-cigarette sales. Differential tax policies based on product type could lead to substitution between different types of e-cigarettes. PMID:24935898

  17. A Modular and Configurable Instrument Electronics Architecture for "MiniSAR"- An Advanced Smallsat SAR Instrument

    NASA Astrophysics Data System (ADS)

    Gomez, Jaime; Pastena, Max; Bierens, Laurens

    2013-08-01

    MiniSAR is a Dutch program focused on the development of a commercial smallsat featuring a SAR instrument, led by SSBV as prime contractor. In this paper an Instrument Electronics (IEL) system concept to meet the MiniSAR demands is presented. This system has several specificities wrt similar initiatives in the European space industry, driven by our main requirement: keep it small.

  18. E-Procurement Success

    DTIC Science & Technology

    2003-03-01

    markets demands that it be given far greater attention than it has received in the past. The new competitive landscape of the twenty-first century...1990’s, the ability for companies to network their electronic systems became cheaper and more reliable which truly brought for the age of e -Business...several business processes into the electronic environment of cyberspace, commonly referred to as e -Business. While e -Business includes all aspects of

  19. Price percolation model

    NASA Astrophysics Data System (ADS)

    Kanai, Yasuhiro; Abe, Keiji; Seki, Yoichi

    2015-06-01

    We propose a price percolation model to reproduce the price distribution of components used in industrial finished goods. The intent is to show, using the price percolation model and a component category as an example, that percolation behaviors, which exist in the matter system, the ecosystem, and human society, also exist in abstract, random phenomena satisfying the power law. First, we discretize the total potential demand for a component category, considering it a random field. Second, we assume that the discretized potential demand corresponding to a function of a finished good turns into actual demand if the difficulty of function realization is less than the maximum difficulty of the realization. The simulations using this model suggest that changes in a component category's price distribution are due to changes in the total potential demand corresponding to the lattice size and the maximum difficulty of realization, which is an occupation probability. The results are verified using electronic components' sales data.

  20. Digital contract approach for consistent and predictable multimedia information delivery in electronic commerce

    NASA Astrophysics Data System (ADS)

    Konana, Prabhudev; Gupta, Alok; Whinston, Andrew B.

    1997-01-01

    A pure 'technological' solution to network quality problems is incomplete since any benefits from new technologies are offset by the demand from exponentially growing electronic commerce ad data-intensive applications. SInce an economic paradigm is implicit in electronic commerce, we propose a 'market-system' approach to improve quality of service. Quality of service for digital products takes on a different meaning since users view quality of service differently and value information differently. We propose a framework for electronic commerce that is based on an economic paradigm and mass-customization, and works as a wide-area distributed management system. In our framework, surrogate-servers act as intermediaries between information provides and end- users, and arrange for consistent and predictable information delivery through 'digital contracts.' These contracts are negotiated and priced based on economic principles. Surrogate servers pre-fetched, through replication, information from many different servers and consolidate based on demand expectations. In order to recognize users' requirements and process requests accordingly, real-time databases are central to our framework. We also propose that multimedia information be separated into slowly changing and rapidly changing data streams to improve response time requirements. Surrogate- servers perform the tasks of integration of these data streams that is transparent to end-users.

  1. Propulsion controls

    NASA Technical Reports Server (NTRS)

    Harkney, R. D.

    1980-01-01

    Increased system requirements and functional integration with the aircraft have placed an increased demand on control system capability and reliability. To provide these at an affordable cost and weight and because of the rapid advances in electronic technology, hydromechanical systems are being phased out in favor of digital electronic systems. The transition is expected to be orderly from electronic trimming of hydromechanical controls to full authority digital electronic control. Future propulsion system controls will be highly reliable full authority digital electronic with selected component and circuit redundancy to provide the required safety and reliability. Redundancy may include a complete backup control of a different technology for single engine applications. The propulsion control will be required to communicate rapidly with the various flight and fire control avionics as part of an integrated control concept.

  2. Community health centers tackle rising demands and expectations.

    PubMed

    Hurley, Robert; Felland, Laurie; Lauer, Johanna

    2007-12-01

    As key providers of preventive and primary care for underserved people, including the uninsured, community health centers (CHCs) are the backbone of the U.S. health care safety net. Despite significant federal funding increases, community health centers are struggling to meet rising demand for care, particularly for specialty medical, dental and mental health services, according to findings from the Center for Studying Health System Change's (HSC) 2007 site visits to 12 nationally representative metropolitan communities. Health centers are responding to these pressures by expanding capacity and adding services but confront staffing, resource and other constraints. At the same time, CHCs are facing other demands, including increased quality reporting expectations, addressing racial and ethnic disparities, developing electronic medical records, and preparing for public health emergencies.

  3. Multigigabit optical transceivers for high-data rate military applications

    NASA Astrophysics Data System (ADS)

    Catanzaro, Brian E.; Kuznia, Charlie

    2012-01-01

    Avionics has experienced an ever increasing demand for processing power and communication bandwidth. Currently deployed avionics systems require gigabit communication using opto-electronic transceivers connected with parallel optical fiber. Ultra Communications has developed a series of transceiver solutions combining ASIC technology with flip-chip bonding and advanced opto-mechanical molded optics. Ultra Communications custom high speed ASIC chips are developed using an SoS (silicon on sapphire) process. These circuits are flip chip bonded with sources (VCSEL arrays) and detectors (PIN diodes) to create an Opto-Electronic Integrated Circuit (OEIC). These have been combined with micro-optics assemblies to create transceivers with interfaces to standard fiber array (MT) cabling technology. We present an overview of the demands for transceivers in military applications and how new generation transceivers leverage both previous generation military optical transceivers as well as commercial high performance computing optical transceivers.

  4. Bio-orthogonal Fluorescent Labelling of Biopolymers through Inverse-Electron-Demand Diels-Alder Reactions.

    PubMed

    Kozma, Eszter; Demeter, Orsolya; Kele, Péter

    2017-03-16

    Bio-orthogonal labelling schemes based on inverse-electron-demand Diels-Alder (IEDDA) cycloaddition have attracted much attention in chemical biology recently. The appealing features of this reaction, such as the fast reaction kinetics, fully bio-orthogonal nature and high selectivity, have helped chemical biologists gain deeper understanding of biochemical processes at the molecular level. Listing the components and discussing the possibilities and limitations of these reagents, we provide a recent snapshot of the field of IEDDA-based biomolecular manipulation with special focus on fluorescent modulation approaches through the use of bio-orthogonalized building blocks. At the end, we discuss challenges that need to be addressed for further developments in order to overcome recent limitations and to enable researchers to answer biomolecular questions in more detail. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  5. Insinuating electronics in the brain.

    PubMed

    Hughes, Mark A

    2016-08-01

    There is an expanding interface between electronic engineering and neurosurgery. Rapid advances in microelectronics and materials science, driven largely by consumer demand, are inspiring and accelerating development of a new generation of diagnostic, therapeutic, and prosthetic devices for implantation in the nervous system. This paper reviews some of the basic science underpinning their development and outlines some opportunities and challenges for their use in neurosurgery. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.

  6. Divergent chemo-, regio-, and diastereoselective normal electron-demand Povarov-type reactions with α-oxo-ketene dienophiles.

    PubMed

    Galvez, Jaime; Castillo, Juan-Carlos; Quiroga, Jairo; Rajzmann, Michel; Rodriguez, Jean; Coquerel, Yoann

    2014-08-15

    The reactions between electron-rich 2-aza-dienes and α-oxo-ketenes derived from the Wolff rearrangement of 2-diazocycloalkane-1,3-diones chemo- and regioselectively produced spiro hydropyrid-4-ones with good to excellent diastereoselectivities. These reactions are likely to proceed via a domino Wolff/Friedel-Crafts/intramolecular Mannich process. Prolonged domino sequences also allowed the expeditious preparation of a series of pyrazolopyridine and pyridopyrimidine heterocycles.

  7. Ultrafast Processes in Atoms and Molecules: Integrated treatment of electronic and nuclear motion in ultrashort XUV pulses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McCurdy, C. William

    This project made use of Multiconfiguration Time-Dependent Hartree-Fock method developed earlier in the McCurdy group in a series of novel applications of the method to ultrafast spectroscopic processes. MCTDHF treats the dynamics of a molecule or atom under the influence of an external field in manner that has all electrons active. That property distinguishes this method from the more popular (and much less computationally demanding) approaches for treating the electron dynamics of atoms and molecules in fields, such as the time-dependent “Configuration Interaction Singles” approximation or approaches that limit the treatment to either one or two-electron models.

  8. High resolution X-ray CT for advanced electronics packaging

    NASA Astrophysics Data System (ADS)

    Oppermann, M.; Zerna, T.

    2017-02-01

    Advanced electronics packaging is a challenge for non-destructive Testing (NDT). More, smaller and mostly hidden interconnects dominate modern electronics components and systems. To solve the demands of customers to get products with a high functionality by low volume, weight and price (e.g. mobile phones, personal medical monitoring systems) often the designers use System-in-Package solutions (SiP). The non-destructive testing of such devices is a big challenge. So our paper will impart fundamentals and applications for non-destructive evaluation of inner structures of electronics packaging for quality assurance and reliability investigations with a focus on X-ray methods, especially on high resolution X-ray computed tomography (CT).

  9. New Rage on Campus: E-Commerce Degrees.

    ERIC Educational Resources Information Center

    Dobbs, Kevin

    1999-01-01

    As electronic commerce expands, higher education attempts to keep up with the demand for instruction. Some universities have added a concentration in e-commerce to their master of business administration program and others are adding majors, certifications, or degrees. (JOW)

  10. The Internet: Trends and Directions.

    ERIC Educational Resources Information Center

    Anderson, Byron

    1996-01-01

    Examines current trends and directions in information technology and telecommunications. Discusses legislation; mergers and acquisitions; Internet service providers; fiscal control in libraries and the pooling of electronic information access through consortiums; demand for more bandwidth; technology selection; Internet usage patterns; the…

  11. Advanced educational program in optoelectronics for undergraduates and graduates in electronics

    NASA Astrophysics Data System (ADS)

    Vladescu, Marian; Schiopu, Paul

    2015-02-01

    The optoelectronics education included in electronics curricula at Faculty of Electronics, Telecommunications and Information Technology of "Politehnica" University of Bucharest started in early '90s, and evolved constantly since then, trying to address the growing demand of engineers with a complex optoelectronics profile and to meet the increased requirements of microelectronics, optoelectronics, and lately nanotechnologies. Our goal is to provide a high level of theoretical background combined with advanced experimental tools in laboratories, and also with simulation platforms. That's why we propose an advanced educational program in optoelectronics for both grades of our study program, bachelor and master.

  12. A conservative, relativistic Fokker-Planck solver for runaway electrons

    NASA Astrophysics Data System (ADS)

    Chacon, Luis; Taitano, W.; Tang, X.; Guo, Z.; McDevitt, C.

    2017-10-01

    Relativistic runaway electrons develop when electric fields surpass a critical electric field, Ec =EDvth/c 2 , with ED the Dreicer field (which is the electric field at which the whole thermal electron population runs away). Above this critical field, electron tails accelerate relativistically until they are arrested by radiative processes. In regimes above this critical electric field (but below the Dreicer field), correctly capturing the interplay between the electron thermal population and the runaway tail is key, and demands a full nonlinear relativistic Fokker-Planck treatment. In this presentation, we report on progress towards a fully conservative, implicit, adaptive implementation of the relativistic electron Fokker-Planck equation. Strict conservation properties, as well as positivity preservation, are a must to avoid spurious numerical effects, and to be able to capture tenuous electron runaway tails for fields just above Ec.

  13. A radiation-tolerant electronic readout system for portal imaging

    NASA Astrophysics Data System (ADS)

    Östling, J.; Brahme, A.; Danielsson, M.; Iacobaeus, C.; Peskov, V.

    2004-06-01

    A new electronic portal imaging device, EPID, is under development at the Karolinska Institutet and the Royal Institute of Technology. Due to considerable demands on radiation tolerance in the radiotherapy environment, a dedicated electronic readout system has been designed. The most interesting aspect of the readout system is that it allows to read out ˜1000 pixels in parallel, with all electronics placed outside the radiation beam—making the detector more radiation resistant. In this work we are presenting the function of a small prototype (6×100 pixels) of the electronic readout board that has been tested. Tests were made with continuous X-rays (10-60 keV) and with α particles. The results show that, without using an optimised gas mixture and with an early prototype only, the electronic readout system still works very well.

  14. Electron dynamics in Hall thruster

    NASA Astrophysics Data System (ADS)

    Marini, Samuel; Pakter, Renato

    2015-11-01

    Hall thrusters are plasma engines those use an electromagnetic fields combination to confine electrons, generate and accelerate ions. Widely used by aerospace industries those thrusters stand out for its simple geometry, high specific impulse and low demand for electric power. Propulsion generated by those systems is due to acceleration of ions produced in an acceleration channel. The ions are generated by collision of electrons with propellant gas atoms. In this context, we can realize how important is characterizing the electronic dynamics. Using Hamiltonian formalism, we derive the electron motion equation in a simplified electromagnetic fields configuration observed in hall thrusters. We found conditions those must be satisfied by electromagnetic fields to have electronic confinement in acceleration channel. We present configurations of electromagnetic fields those maximize propellant gas ionization and thus make propulsion more efficient. This work was supported by CNPq.

  15. Direction of CRT waste glass processing: Electronics recycling industry communication

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mueller, Julia R., E-mail: mueller.143@osu.edu; Boehm, Michael W.; Drummond, Charles

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer Given a large flow rate of CRT glass {approx}10% of the panel glass stream will be leaded. Black-Right-Pointing-Pointer The supply of CRT waste glass exceeded demand in 2009. Black-Right-Pointing-Pointer Recyclers should use UV-light to detect lead oxide during the separation process. Black-Right-Pointing-Pointer Recycling market analysis techniques and results are given for CRT glass. Black-Right-Pointing-Pointer Academic initiatives and the necessary expansion of novel product markets are discussed. - Abstract: Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, andmore » the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased.« less

  16. GAGG:ce single crystalline films: New perspective scintillators for electron detection in SEM.

    PubMed

    Bok, Jan; Lalinský, Ondřej; Hanuš, Martin; Onderišinová, Zuzana; Kelar, Jakub; Kučera, Miroslav

    2016-04-01

    Single crystal scintillators are frequently used for electron detection in scanning electron microscopy (SEM). We report gadolinium aluminum gallium garnet (GAGG:Ce) single crystalline films as a new perspective scintillators for the SEM. For the first time, the epitaxial garnet films were used in a practical application: the GAGG:Ce scintillator was incorporated into a SEM scintillation electron detector and it showed improved image quality. In order to prove the GAGG:Ce quality accurately, the scintillation properties were examined using electron beam excitation and compared with frequently used scintillators in the SEM. The results demonstrate excellent emission efficiency of the GAGG:Ce single crystalline films together with their very fast scintillation decay useful for demanding SEM applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Technology-based strategies for promoting clinical reasoning skills in nursing education.

    PubMed

    Shellenbarger, Teresa; Robb, Meigan

    2015-01-01

    Faculty face the demand of preparing nursing students for the constantly changing health care environment. Effective use of online, classroom, and clinical conferencing opportunities helps to enhance nursing students' clinical reasoning capabilities needed for practice. The growth of technology creates an avenue for faculty to develop engaging learning opportunities. This article presents technology-based strategies such as electronic concept mapping, electronic case histories, and digital storytelling that can be used to facilitate clinical reasoning skills.

  18. Sales forecasting newspaper with ARIMA: A case study

    NASA Astrophysics Data System (ADS)

    Permatasari, Carina Intan; Sutopo, Wahyudi; Hisjam, Muh.

    2018-02-01

    People are beginning to switch to using digital media for their daily activities, including changes in newspaper reading patterns to electronic news. In uncertainty trend, the customers of printed newspaper also have switched to electronic news. It has some negative effects on the printed newspaper demand, where there is often an inaccuracy of supply with demand which means that many newspapers are returned. The aim of this paper is to predict printed newspaper demand as accurately as possible to minimize the number of returns, to keep off the missed sales and to restrain the oversupply. The autoregressive integrated moving average (ARIMA) models were adopted to predict the right number of newspapers for a real case study of a newspaper company in Surakarta. The model parameters were found using maximum likelihood method. Then, the software Eviews 9 were utilized to forecasting any particular variables in the newspaper industry. This paper finally presents the appropriate of modeling and sales forecasting newspaper based on the output of the ARIMA models. In particular, it can be recommended to use ARIMA (1, 1, 0) model in predicting the number of newspapers. ARIMA (1, 1, 0) model was chosen from three different models that it provides the smallest value of the mean absolute percentage error (MAPE).

  19. China's Rare Earth Supply Chain: Illegal Production, and Response to new Cerium Demand

    NASA Astrophysics Data System (ADS)

    Nguyen, Ruby Thuy; Imholte, D. Devin

    2016-07-01

    As the demand for personal electronic devices, wind turbines, and electric vehicles increases, the world becomes more dependent on rare earth elements. Given the volatile, Chinese-concentrated supply chain, global attempts have been made to diversify supply of these materials. However, the overall effect of supply diversification on the entire supply chain, including increasing low-value rare earth demand, is not fully understood. This paper is the first attempt to shed some light on China's supply chain from both demand and supply perspectives, taking into account different Chinese policies such as mining quotas, separation quotas, export quotas, and resource taxes. We constructed a simulation model using Powersim Studio that analyzes production (both legal and illegal), production costs, Chinese and rest-of-world demand, and market dynamics. We also simulated new demand of an automotive aluminum-cerium alloy in the US market starting from 2018. Results showed that market share of the illegal sector has grown since 2007-2015, ranging between 22% and 25% of China's rare earth supply, translating into 59-65% illegal heavy rare earths and 14-16% illegal light rare earths. There will be a shortage in certain light and heavy rare earths given three production quota scenarios and constant demand growth rate from 2015 to 2030. The new simulated Ce demand would require supply beyond that produced in China. Finally, we illustrate revenue streams for different ore compositions in China in 2015.

  20. China’s rare earth supply chain: Illegal production, and response to new cerium demand

    DOE PAGES

    Nguyen, Ruby Thuy; Imholte, D. Devin

    2016-03-29

    As the demand for personal electronic devices, wind turbines, and electric vehicles increases, the world becomes more dependent on rare earth elements. Given the volatile, Chinese-concentrated supply chain, global attempts have been made to diversify supply of these materials. However, the overall effect of supply diversification on the entire supply chain, including increasing low-value rare earth demand, is not fully understood. This paper is the first attempt to shed some light on China’s supply chain from both demand and supply perspectives, taking into account different Chinese policies such as mining quotas, separation quotas, export quotas, and resource taxes. We constructedmore » a simulation model using Powersim Studio that analyzes production (both legal and illegal), production costs, Chinese and rest-of-world demand, and market dynamics. We also simulated new demand of an automotive aluminum-cerium alloy in the U.S. market starting from 2018. Results showed that market share of the illegal sector has grown since 2007 to 2015, ranging between 22% and 25% of China’s rare earth supply, translating into 59–65% illegal heavy rare earths and 14–16% illegal light rare earths. There would be a shortage in certain light and heavy rare earths given three production quota scenarios and constant demand growth rate from 2015 to 2030. The new simulated Ce demand would require supply beyond that produced in China. Lastly, we illustrated revenue streams for different ore compositions in China in 2015.« less

  1. China’s rare earth supply chain: Illegal production, and response to new cerium demand

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, Ruby Thuy; Imholte, D. Devin

    As the demand for personal electronic devices, wind turbines, and electric vehicles increases, the world becomes more dependent on rare earth elements. Given the volatile, Chinese-concentrated supply chain, global attempts have been made to diversify supply of these materials. However, the overall effect of supply diversification on the entire supply chain, including increasing low-value rare earth demand, is not fully understood. This paper is the first attempt to shed some light on China’s supply chain from both demand and supply perspectives, taking into account different Chinese policies such as mining quotas, separation quotas, export quotas, and resource taxes. We constructedmore » a simulation model using Powersim Studio that analyzes production (both legal and illegal), production costs, Chinese and rest-of-world demand, and market dynamics. We also simulated new demand of an automotive aluminum-cerium alloy in the U.S. market starting from 2018. Results showed that market share of the illegal sector has grown since 2007 to 2015, ranging between 22% and 25% of China’s rare earth supply, translating into 59–65% illegal heavy rare earths and 14–16% illegal light rare earths. There would be a shortage in certain light and heavy rare earths given three production quota scenarios and constant demand growth rate from 2015 to 2030. The new simulated Ce demand would require supply beyond that produced in China. Lastly, we illustrated revenue streams for different ore compositions in China in 2015.« less

  2. Material Selection for Microchannel Heatsink: Conjugate Heat Transfer Simulation

    NASA Astrophysics Data System (ADS)

    Uday Kumar, A.; Javed, Arshad; Dubey, Satish K.

    2018-04-01

    Heat dissipation during the operation of electronic devices causes rise in temperature, which demands an effective thermal management for their performance, life and reliability. Single phase liquid cooling in microchannels is an effective and proven technology for electronics cooling. However, due to the ongoing trends of miniaturization and developments in the microelectronics technology, the future needs of heat flux dissipation rate are expected to rise to 1 kW/cm2. Air cooled systems are unable to meet this demand. Hence, liquid cooled heatsinks are preferred. This paper presents conjugate heat transfer simulation of single phase flow in microchannels with application to electronic cooling. The numerical model is simulated for different materials: copper, aluminium and silicon as solid and water as liquid coolant. The performances of microchannel heatsink are analysed for mass flow rate range of 20-40 ml/min. The investigation has been carried out on same size of electronic chip and heat flux in order to have comparative study of different materials. This paper is divided into two sections: fabrication techniques and numerical simulation for different materials. In the first part, a brief discussion of fabrication techniques of microchannel heatsink have been presented. The second section presents conjugate heat transfer simulation and parametric investigation for different material microchannel heatsink. The presented study and findings are useful for selection of materials for microchannel heatsink.

  3. Effect of temperature on photosynthesis and growth in marine Synechococcus spp.

    PubMed

    Mackey, Katherine R M; Paytan, Adina; Caldeira, Ken; Grossman, Arthur R; Moran, Dawn; McIlvin, Matthew; Saito, Mak A

    2013-10-01

    In this study, we develop a mechanistic understanding of how temperature affects growth and photosynthesis in 10 geographically and physiologically diverse strains of Synechococcus spp. We found that Synechococcus spp. are able to regulate photochemistry over a range of temperatures by using state transitions and altering the abundance of photosynthetic proteins. These strategies minimize photosystem II (PSII) photodamage by keeping the photosynthetic electron transport chain (ETC), and hence PSII reaction centers, more oxidized. At temperatures that approach the optimal growth temperature of each strain when cellular demand for reduced nicotinamide adenine dinucleotide phosphate (NADPH) is greatest, the phycobilisome (PBS) antenna associates with PSII, increasing the flux of electrons into the ETC. By contrast, under low temperature, when slow growth lowers the demand for NADPH and linear ETC declines, the PBS associates with photosystem I. This favors oxidation of PSII and potential increase in cyclic electron flow. For Synechococcus sp. WH8102, growth at higher temperatures led to an increase in the abundance of PBS pigment proteins, as well as higher abundance of subunits of the PSII, photosystem I, and cytochrome b6f complexes. This would allow cells to increase photosynthetic electron flux to meet the metabolic requirement for NADPH during rapid growth. These PBS-based temperature acclimation strategies may underlie the larger geographic range of this group relative to Prochlorococcus spp., which lack a PBS.

  4. PHOTOCROSSLINKED IMMOBILIZATION OF POLYELECTROLYTES FOR TEMPLATE ASSISTED ENZYMATIC POLYMERIZATION OF CONJUGATED POLYMERS

    EPA Science Inventory

    Growing demand in consumer electronics raises need for efficient, affordable, environmentally benign and biodegradable substitutes for current technologies. Printed circuit boards contain heavy metals such as antimony, silver, chromium, zinc, lead, tin and copper. According t...

  5. Tabletop Imaging of Structural Evolutions in Chemical Reactions

    NASA Astrophysics Data System (ADS)

    Ibrahim, Heide; Wales, Benji; Beaulieu, Samuel; Schmidt, Bruno E.; Thiré, Nicolas; Fowe, Emmanuel P.; Bisson, Éric; Hebeisen, Christoph T.; Wanie, Vincent; Giguére, Mathieu; Kieffer, Jean-Claude; Spanner, Michael; Bandrauk, André D.; Sanderson, Joseph; Schuurman, Michael S.; Légaré, François

    The first high-resolution molecular movie of proton migration in the acetylene cation is obtained using a tabletop multiphoton pump-probe approach—an alternative to demanding free-electron-lasers and other VUV light sources when ionizing from the HOMO-1.

  6. Toward a better understanding of task demands, workload, and performance during physician-computer interactions.

    PubMed

    Mazur, Lukasz M; Mosaly, Prithima R; Moore, Carlton; Comitz, Elizabeth; Yu, Fei; Falchook, Aaron D; Eblan, Michael J; Hoyle, Lesley M; Tracton, Gregg; Chera, Bhishamjit S; Marks, Lawrence B

    2016-11-01

    To assess the relationship between (1) task demands and workload, (2) task demands and performance, and (3) workload and performance, all during physician-computer interactions in a simulated environment. Two experiments were performed in 2 different electronic medical record (EMR) environments: WebCIS (n = 12) and Epic (n = 17). Each participant was instructed to complete a set of prespecified tasks on 3 routine clinical EMR-based scenarios: urinary tract infection (UTI), pneumonia (PN), and heart failure (HF). Task demands were quantified using behavioral responses (click and time analysis). At the end of each scenario, subjective workload was measured using the NASA-Task-Load Index (NASA-TLX). Physiological workload was measured using pupillary dilation and electroencephalography (EEG) data collected throughout the scenarios. Performance was quantified based on the maximum severity of omission errors. Data analysis indicated that the PN and HF scenarios were significantly more demanding than the UTI scenario for participants using WebCIS (P < .01), and that the PN scenario was significantly more demanding than the UTI and HF scenarios for participants using Epic (P < .01). In both experiments, the regression analysis indicated a significant relationship only between task demands and performance (P < .01). Results suggest that task demands as experienced by participants are related to participants' performance. Future work may support the notion that task demands could be used as a quality metric that is likely representative of performance, and perhaps patient outcomes. The present study is a reasonable next step in a systematic assessment of how task demands and workload are related to performance in EMR-evolving environments. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Electron Impact Ionization: A New Parameterization for 100 eV to 1 MeV Electrons

    NASA Technical Reports Server (NTRS)

    Fang, Xiaohua; Randall, Cora E.; Lummerzheim, Dirk; Solomon, Stanley C.; Mills, Michael J.; Marsh, Daniel; Jackman, Charles H.; Wang, Wenbin; Lu, Gang

    2008-01-01

    Low, medium and high energy electrons can penetrate to the thermosphere (90-400 km; 55-240 miles) and mesosphere (50-90 km; 30-55 miles). These precipitating electrons ionize that region of the atmosphere, creating positively charged atoms and molecules and knocking off other negatively charged electrons. The precipitating electrons also create nitrogen-containing compounds along with other constituents. Since the electron precipitation amounts change within minutes, it is necessary to have a rapid method of computing the ionization and production of nitrogen-containing compounds for inclusion in computationally-demanding global models. A new methodology has been developed, which has parameterized a more detailed model computation of the ionizing impact of precipitating electrons over the very large range of 100 eV up to 1,000,000 eV. This new parameterization method is more accurate than a previous parameterization scheme, when compared with the more detailed model computation. Global models at the National Center for Atmospheric Research will use this new parameterization method in the near future.

  8. Networked Multimedia: Are We There Yet?

    ERIC Educational Resources Information Center

    Wyman, Bill

    1997-01-01

    Discusses the technological advances in electronic communication over the last 30 years. Touches on various real-time interactive multimedia communications, including video on demand, videocassettes, laser discs, CD-ROM, a history of networking, terminal/host and client/server networking, intraoperability and interoperability and multimedia…

  9. Development of a short course in transportation planning for electronic delivery to DOTD.

    DOT National Transportation Integrated Search

    2000-12-01

    This report describes the preparation, delivery, and evaluation of a short course developed for delivery through compressed video to remote sites. The course covered basics of travel demand models and involved approximately 28 hours of classroom cont...

  10. Redundant electronic circuit provides fail-safe control

    NASA Technical Reports Server (NTRS)

    Archer, J. W.

    1970-01-01

    Circuit using dual control amplifiers and dual position demand potentiometers powered from separate sources is used for reliable hydraulic valve controller that prevents closure of valve when control circuits fail, and maintains valve control to close tolerance for more common modes of controller failure.

  11. Platinum replica electron microscopy: Imaging the cytoskeleton globally and locally.

    PubMed

    Svitkina, Tatyana M

    2017-05-01

    Structural studies reveal how smaller components of a system work together as a whole. However, combining high resolution of details with full coverage of the whole is challenging. In cell biology, light microscopy can image many cells in their entirety, but at a lower resolution, whereas electron microscopy affords very high resolution, but usually at the expense of the sample size and coverage. Structural analyses of the cytoskeleton are especially demanding, because cytoskeletal networks are unresolvable by light microscopy due to their density and intricacy, whereas their proper preservation is a challenge for electron microscopy. Platinum replica electron microscopy can uniquely bridge the gap between the "comfort zones" of light and electron microscopy by allowing high resolution imaging of the cytoskeleton throughout the entire cell and in many cells in the population. This review describes the principles and applications of platinum replica electron microscopy for studies of the cytoskeleton. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Platinum Replica Electron Microscopy: Imaging the Cytoskeleton Globally and Locally

    PubMed Central

    SVITKINA, Tatyana M.

    2017-01-01

    Structural studies reveal how smaller components of a system work together as a whole. However, combining high resolution of details with full coverage of the whole is challenging. In cell biology, light microscopy can image many cells in their entirety, but at a lower resolution, whereas electron microscopy affords very high resolution, but usually at the expense of the sample size and coverage. Structural analyses of the cytoskeleton are especially demanding, because cytoskeletal networks are unresolvable by light microscopy due to their density and intricacy, whereas their proper preservation is a challenge for electron microscopy. Platinum replica electron microscopy can uniquely bridge the gap between the “comfort zones” of light and electron microscopy by allowing high resolution imaging of the cytoskeleton throughout the entire cell and in many cells in the population. This review describes the principles and applications of platinum replica electron microscopy for studies of the cytoskeleton. PMID:28323208

  13. Solar X-Ray Processes

    NASA Astrophysics Data System (ADS)

    Mallik, P. C. V.; Brown, J. C.; MacKinnon, A. L.

    Past analyses of solar flares have ignored nonthermal recombination (NTR) emission as a means of producing Hard X-rays (HXRs) in the corona and chromosphere. However, Brown and Mallik (2008, A&A, 481, 507) have shown that NTR can be significant and even exceed nonthermal bremsstrahlung (NTB) emission for certain flare conditions that are quite common. For hot enough plasma (T > 10 MK), HXR emission of a few deka-keV has a large contribution from NTR onto highly ionized heavy elements, especially Fe. Consequently, including NTR has implications for the magnitude and the form of the inferred electron spectrum, F(E), and hence for fast-electron density and energy budgets and for the acceleration mechanisms. We show under what circumstances NTR dominates in deka-keV HXR emission. It is important to note that at high temperatures, HXR emission from thermal electrons (recombination and bremsstrahlung) becomes important. However, NTR dominates over NTB without being swamped by thermal emission in the photon energy (ɛ) regime of 20-30 keV and temperature range of 10-25MK (Fig. 1, left). By integrating the flux for all ɛ > 20keV, i.e., looking at the source luminosity function above 20 keV, we were able to show that by including NTR, the acceleration requirements are less demanding for every event, but to varying degrees based on temperature (T), spectral index (δ) and electron low-energy cut-off (Ec). Our key result is that, for T > 10MK and δ ≈ 5, including NTR reduces the demand for nonthermal electrons by up to 85%. Our paper with these results will be submitted to ApJ Letters.

  14. STTR Phase I: Low-Cost, High-Accuracy, Whole-Building Carbon Dioxide Monitoring for Demand Control Ventilation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hallstrom, Jason O.; Ni, Zheng Richard

    This STTR Phase I project assessed the feasibility of a new CO 2 sensing system optimized for low-cost, high-accuracy, whole-building monitoring for use in demand control ventilation. The focus was on the development of a wireless networking platform and associated firmware to provide signal conditioning and conversion, fault- and disruptiontolerant networking, and multi-hop routing at building scales to avoid wiring costs. Early exploration of a bridge (or “gateway”) to direct digital control services was also explored. Results of the project contributed to an improved understanding of a new electrochemical sensor for monitoring indoor CO 2 concentrations, as well as themore » electronics and networking infrastructure required to deploy those sensors at building scales. New knowledge was acquired concerning the sensor’s accuracy, environmental response, and failure modes, and the acquisition electronics required to achieve accuracy over a wide range of CO 2 concentrations. The project demonstrated that the new sensor offers repeatable correspondence with commercial optical sensors, with supporting electronics that offer gain accuracy within 0.5%, and acquisition accuracy within 1.5% across three orders of magnitude variation in generated current. Considering production, installation, and maintenance costs, the technology presents a foundation for achieving whole-building CO 2 sensing at a price point below $0.066 / sq-ft – meeting economic feasibility criteria established by the Department of Energy. The technology developed under this award addresses obstacles on the critical path to enabling whole-building CO 2 sensing and demand control ventilation in commercial retrofits, small commercial buildings, residential complexes, and other highpotential structures that have been slow to adopt these technologies. It presents an opportunity to significantly reduce energy use throughout the United States.« less

  15. Case study: a health check-up for the corporate IT department.

    PubMed

    Clark, Frank; Kimmerly, William

    2004-01-01

    As advances such as the electronic charting, closed-loop medication safety, physician order entry, consumer portals, electronic collaboration, and wireless access become the norm, central IS organizations are finding it difficult to keep pace. This challenge is exacerbated by declining margins, severe cost pressures, increased regulation, and added public scrutiny. Is your centralized IS organization healthy enough to meet the challenges presented by today's complex, demanding, dynamic healthcare delivery environments? How do you know? What factors do you consider?

  16. Electron Microscopy of Living Cells During in Situ Fluorescence Microscopy

    PubMed Central

    Liv, Nalan; van Oosten Slingeland, Daan S. B.; Baudoin, Jean-Pierre; Kruit, Pieter; Piston, David W.; Hoogenboom, Jacob P.

    2016-01-01

    We present an approach toward dynamic nanoimaging: live fluorescence of cells encapsulated in a bionanoreactor is complemented with in situ scanning electron microscopy (SEM) on an integrated microscope. This allows us to take SEM snapshots on-demand, that is, at a specific location in time, at a desired region of interest, guided by the dynamic fluorescence imaging. We show that this approach enables direct visualization, with EM resolution, of the distribution of bioconjugated quantum dots on cellular extensions during uptake and internalization. PMID:26580231

  17. Molecular diodes based on conjugated diblock co-oligomers.

    PubMed

    Ng, Man-Kit; Lee, Dong-Chan; Yu, Luping

    2002-10-09

    This report describes synthesis and characterization of a molecular diode based upon a diblock conjugated oligomer system. This system consists of two conjugated blocks with opposite electronic demand. The molecular structure exhibits a built-in electronic asymmetry, much like a semiconductor p-n junction. Electrical measurements by scanning tunneling spectroscopy (STS) clearly revealed a pronounced rectifying effect. Definitive proof for the molecular nature of the rectifying effect in this conjugated diblock molecule is provided by control experiments with a structurally similar reference compound.

  18. Printed Electronic Devices in Human Spaceflight

    NASA Technical Reports Server (NTRS)

    Bacon, John B.

    2004-01-01

    The space environment requires robust sensing, control, and automation, whether in support of human spaceflight or of robotic exploration. Spaceflight embodies the known extremes of temperature, radiation, shock, vibration, and static loads, and demands high reliability at the lowest possible mass. Because printed electronic circuits fulfill all these requirements, printed circuit technology and the exploration of space have been closely coupled throughout their short histories. In this presentation, we will explore the space (and space launch) environments as drivers of printed circuit design, a brief history of NASA's use of printed electronic circuits, and we will examine future requirements for such circuits in our continued exploration of space.

  19. High-Performance, Radiation-Hardened Electronics for Space and Lunar Environments

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Adams, James H.; Cressler, John D.; Darty, Ronald C.; Johnson, Michael A.; Patrick, Marshall C.

    2008-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project develops advanced technologies needed for high performance electronic devices that will be capable of operating within the demanding radiation and thermal extremes of the space, lunar, and Martian environment. The technologies developed under this project enhance and enable avionics within multiple mission elements of NASA's Vision for Space Exploration. including the Constellation program's Orion Crew Exploration Vehicle. the Lunar Lander project, Lunar Outpost elements, and Extra Vehicular Activity (EVA) elements. This paper provides an overview of the RHESE project and its multiple task tasks, their technical approaches, and their targeted benefits as applied to NASA missions.

  20. In Search of the Reason for the Breathing Effect of MIL53 Metal-Organic Framework: An ab Initio Multiconfigurational Study.

    PubMed

    Weser, Oskar; Veryazov, Valera

    2017-01-01

    Multiconfigurational methods are applied to study electronic properties and structural changes in the highly flexible metal-organic framework MIL53(Cr). Via calculated bending potentials of angles, that change the most during phase transition, it is verified that the high flexibility of this material is not a question about special electronic properties in the coordination chemistry, but about overall linking of the framework. The complex posseses a demanding electronic structure with delocalized spin density, antifferomagnetic coupling and high multi-state character requiring multiconfigurational methods. Calculated properties are in good agreement with known experimental values confirming our chosen methods.

  1. The impact of price and tobacco control policies on the demand for electronic nicotine delivery systems.

    PubMed

    Huang, Jidong; Tauras, John; Chaloupka, Frank J

    2014-07-01

    While much is known about the demand for conventional cigarettes, little is known about the determinants of demand for electronic nicotine delivery systems (ENDS or e-cigarettes). The goal of this study is to estimate the own and cross-price elasticity of demand for e-cigarettes and to examine the impact of cigarette prices and smoke-free policies on e-cigarette sales. Quarterly e-cigarette prices and sales and conventional cigarette prices from 2009 to 2012 were constructed from commercial retail store scanner data from 52 U.S. markets, for food, drug and mass stores, and from 25 markets, for convenience stores. Fixed-effects models were used to estimate the own and cross-price elasticity of demand for e-cigarettes and associations between e-cigarette sales and cigarette prices and smoke-free policies. Estimated own price elasticities for disposable e-cigarettes centred around -1.2, while those for reusable e-cigarettes were approximately -1.9. Disposable e-cigarette sales were higher in markets where reusable e-cigarette prices were higher and where less of the population was covered by a comprehensive smoke-free policy. There were no consistent and statistically significant relationships between cigarette prices and e-cigarette sales. E-cigarette sales are very responsive to own price changes. Disposable e-cigarettes appear to be substitutes for reusable e-cigarettes. Policies increasing e-cigarette retail prices, such as limiting rebates, discounts and coupons and imposing a tax on e-cigarettes, could potentially lead to significant reductions in e-cigarette sales. Differential tax policies based on product type could lead to substitution between different types of e-cigarettes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  2. The low-lying electronic excitations in long polyenes: A PPP-MRD-CI study

    NASA Astrophysics Data System (ADS)

    Tavan, Paul; Schulten, Klaus

    1986-12-01

    A correct description of the electronic excitations in polyenes demands that electron correlation is accounted for correctly. Very large expansions are necessary including many-electron configurations with at least one, two, three, and four electrons promoted from the Hartree-Fock ground state. The enormous size of such expansions had prohibited accurate computations of the spectra for polyenes with more than ten π electrons. We present a multireference double excitation configuration interaction method (MRD-CI) which allows such computations for polyenes with up to 16 π electrons. We employ a Pariser-Parr-Pople (PPP) model Hamiltonian. For short polyenes with up to ten π electrons our calculations reproduce the excitation energies resulting from full-CI calculations. We extend our calculations to study the low-lying electronic excitations of the longer polyenes, in particular, the gap between the first optically forbidden and the first optically allowed excited singlet state. The size of this gap is shown to depend strongly on the degree of bond alternation and on the dielectric shielding of the Coulomb repulsion between the π electrons.

  3. Test Results for Caustic Demand Measurements on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doll, Stephanie R.; Bolling, Stacie D.

    Caustic demand testing is used to determine the necessary amount of caustic required to neutralize species present in the Hanford tank waste and obtain a target molarity of free hydroxide for tank corrosion control. The presence and quantity of hydroxide-consuming analytes are just as important in determining the caustic demand as is the amount of free hydroxide present. No single data point can accurately predict whether a satisfactory hydroxide level is being met, as it is dependent on multiple factors (e.g., free hydroxide, buffers, amphoteric metal hydroxides, bicarbonate, etc.). This enclosure contains the caustic demand, scanning electron microscopy (SEM), polarizedmore » light microscopy (PLM), and X-ray diffraction (XRD) analysis for the tank 241-AX-101 (AX-101) and 241-AX-103 (AX-103) samples. The work was completed to fulfill a customer request outlined in the test plan, WRPS-1505529, “Test Plan and Procedure for Caustic Demand Testing on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples.” The work results will provide a baseline to support planned retrieval of AX-101 and AX-103.« less

  4. Quiet, Computer at Work.

    ERIC Educational Resources Information Center

    Black, Claudia

    Libraries are becoming information access points, not just book repositories. With greater distribution of printed materials, increased use of optical disks and other compact storage techniques, the emergence of publication on demand, and the proliferation of electronic databases, libraries without large collections will be able to provide prompt…

  5. A Course on Reconfigurable Processors

    ERIC Educational Resources Information Center

    Shoufan, Abdulhadi; Huss, Sorin A.

    2010-01-01

    Reconfigurable computing is an established field in computer science. Teaching this field to computer science students demands special attention due to limited student experience in electronics and digital system design. This article presents a compact course on reconfigurable processors, which was offered at the Technische Universitat Darmstadt,…

  6. Data Destruction

    ERIC Educational Resources Information Center

    Bergren, Martha Dewey

    2005-01-01

    School nurses are caretakers of a vast amount of sensitive student and family health information. In schools, older computer hardware that previously stored education records is recycled for less demanding student and employee functions. Sensitive data must be adequately erased before electronic storage devices are reassigned or are discarded.…

  7. Nanoarchitectured graphene-based supercapacitors for next-generation energy-storage applications.

    PubMed

    Salunkhe, Rahul R; Lee, Ying-Hui; Chang, Kuo-Hsin; Li, Jing-Mei; Simon, Patrice; Tang, Jing; Torad, Nagy L; Hu, Chi-Chang; Yamauchi, Yusuke

    2014-10-20

    Tremendous development in the field of portable electronics and hybrid electric vehicles has led to urgent and increasing demand in the field of high-energy storage devices. In recent years, many research efforts have been made for the development of more efficient energy-storage devices such as supercapacitors, batteries, and fuel cells. In particular, supercapacitors have great potential to meet the demands of both high energy density and power density in many advanced technologies. For the last half decade, graphene has attracted intense research interest for electrical double-layer capacitor (EDLC) applications. The unique electronic, thermal, mechanical, and chemical characteristics of graphene, along with the intrinsic benefits of a carbon material, make it a promising candidate for supercapacitor applications. This Review focuses on recent research developments in graphene-based supercapacitors, including doped graphene, activated graphene, graphene/metal oxide composites, graphene/polymer composites, and graphene-based asymmetric supercapacitors. The challenges and prospects of graphene-based supercapacitors are also discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Drop-on-demand sample delivery for studying biocatalysts in action at X-ray free-electron lasers.

    PubMed

    Fuller, Franklin D; Gul, Sheraz; Chatterjee, Ruchira; Burgie, E Sethe; Young, Iris D; Lebrette, Hugo; Srinivas, Vivek; Brewster, Aaron S; Michels-Clark, Tara; Clinger, Jonathan A; Andi, Babak; Ibrahim, Mohamed; Pastor, Ernest; de Lichtenberg, Casper; Hussein, Rana; Pollock, Christopher J; Zhang, Miao; Stan, Claudiu A; Kroll, Thomas; Fransson, Thomas; Weninger, Clemens; Kubin, Markus; Aller, Pierre; Lassalle, Louise; Bräuer, Philipp; Miller, Mitchell D; Amin, Muhamed; Koroidov, Sergey; Roessler, Christian G; Allaire, Marc; Sierra, Raymond G; Docker, Peter T; Glownia, James M; Nelson, Silke; Koglin, Jason E; Zhu, Diling; Chollet, Matthieu; Song, Sanghoon; Lemke, Henrik; Liang, Mengning; Sokaras, Dimosthenis; Alonso-Mori, Roberto; Zouni, Athina; Messinger, Johannes; Bergmann, Uwe; Boal, Amie K; Bollinger, J Martin; Krebs, Carsten; Högbom, Martin; Phillips, George N; Vierstra, Richard D; Sauter, Nicholas K; Orville, Allen M; Kern, Jan; Yachandra, Vittal K; Yano, Junko

    2017-04-01

    X-ray crystallography at X-ray free-electron laser sources is a powerful method for studying macromolecules at biologically relevant temperatures. Moreover, when combined with complementary techniques like X-ray emission spectroscopy, both global structures and chemical properties of metalloenzymes can be obtained concurrently, providing insights into the interplay between the protein structure and dynamics and the chemistry at an active site. The implementation of such a multimodal approach can be compromised by conflicting requirements to optimize each individual method. In particular, the method used for sample delivery greatly affects the data quality. We present here a robust way of delivering controlled sample amounts on demand using acoustic droplet ejection coupled with a conveyor belt drive that is optimized for crystallography and spectroscopy measurements of photochemical and chemical reactions over a wide range of time scales. Studies with photosystem II, the phytochrome photoreceptor, and ribonucleotide reductase R2 illustrate the power and versatility of this method.

  9. Drop-on-demand sample delivery for studying biocatalysts in action at X-ray free-electron lasers

    DOE PAGES

    Fuller, Franklin D.; Gul, Sheraz; Chatterjee, Ruchira; ...

    2017-02-27

    X-ray crystallography at X-ray free-electron laser (XFEL) sources is a powerful method for studying macromolecules at biologically relevant temperatures. Moreover, when combined with complementary techniques like X-ray emission spectroscopy (XES), both global structures and chemical properties of metalloenzymes can be obtained concurrently, providing new insights into the interplay between the protein structure/dynamics and chemistry at an active site. However, implementing such a multimodal approach can be compromised by conflicting requirements to optimize each individual method. In particular, the method used for sample delivery greatly impacts the data quality. We present here a new, robust way of delivering controlled sample amountsmore » on demand using acoustic droplet ejection coupled with a conveyor belt drive that is optimized for crystallography and spectroscopy measurements of photochemical and chemical reactions over a wide range of time scales. Studies with photosystem II, the phytochrome photoreceptor, and ribonucleotide reductase R2 illustrate the power and versatility of this method.« less

  10. Drop-on-demand sample delivery for studying biocatalysts in action at X-ray free-electron lasers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fuller, Franklin D.; Gul, Sheraz; Chatterjee, Ruchira

    X-ray crystallography at X-ray free-electron laser (XFEL) sources is a powerful method for studying macromolecules at biologically relevant temperatures. Moreover, when combined with complementary techniques like X-ray emission spectroscopy (XES), both global structures and chemical properties of metalloenzymes can be obtained concurrently, providing new insights into the interplay between the protein structure/dynamics and chemistry at an active site. However, implementing such a multimodal approach can be compromised by conflicting requirements to optimize each individual method. In particular, the method used for sample delivery greatly impacts the data quality. We present here a new, robust way of delivering controlled sample amountsmore » on demand using acoustic droplet ejection coupled with a conveyor belt drive that is optimized for crystallography and spectroscopy measurements of photochemical and chemical reactions over a wide range of time scales. Studies with photosystem II, the phytochrome photoreceptor, and ribonucleotide reductase R2 illustrate the power and versatility of this method.« less

  11. Survey Of High Speed Test Techniques

    NASA Astrophysics Data System (ADS)

    Gheewala, Tushar

    1988-02-01

    The emerging technologies for the characterization and production testing of high-speed devices and integrated circuits are reviewed. The continuing progress in the field of semiconductor technologies will, in the near future, demand test techniques to test 10ps to lOOps gate delays, 10 GHz to 100 GHz analog functions and 10,000 to 100,000 gates on a single chip. Clearly, no single test technique would provide a cost-effective answer to all the above demands. A divide-and-conquer approach based on a judicial selection of parametric, functional and high-speed tests will be required. In addition, design-for-test methods need to be pursued which will include on-chip test electronics as well as circuit techniques that minimize the circuit performance sensitivity to allowable process variations. The electron and laser beam based test technologies look very promising and may provide the much needed solutions to not only the high-speed test problem but also to the need for high levels of fault coverage during functional testing.

  12. Global demand for rare earth resources and strategies for green mining

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dutta, Tanushree

    Rare earth elements (REEs) are essential raw materials for emerging renewable energy resources and ‘smart’ electronic devices. Global REE demand is slated to grow at an annual rate of 5% by 2020. This high growth rate will require a steady supply base of REEs in the long run. At present, China is responsible for 85% of global rare earth oxide (REO) production. To overcome this monopolistic supply situation, new strategies and investments are necessary to satisfy domestic supply demands. Concurrently, environmental, economic, and social problems arising from REE mining must be addressed. There is an urgent need to develop efficientmore » REE recycling techniques from end-of-life products, technologies to minimize the amount of REEs required per unit device, and methods to recover them from fly ash or fossil fuel-burning wastes.« less

  13. Global demand for rare earth resources and strategies for green mining.

    PubMed

    Dutta, Tanushree; Kim, Ki-Hyun; Uchimiya, Minori; Kwon, Eilhann E; Jeon, Byong-Hun; Deep, Akash; Yun, Seong-Taek

    2016-10-01

    Rare earth elements (REEs) are essential raw materials for emerging renewable energy resources and 'smart' electronic devices. Global REE demand is slated to grow at an annual rate of 5% by 2020. This high growth rate will require a steady supply base of REEs in the long run. At present, China is responsible for 85% of global rare earth oxide (REO) production. To overcome this monopolistic supply situation, new strategies and investments are necessary to satisfy domestic supply demands. Concurrently, environmental, economic, and social problems arising from REE mining must be addressed. There is an urgent need to develop efficient REE recycling techniques from end-of-life products, technologies to minimize the amount of REEs required per unit device, and methods to recover them from fly ash or fossil fuel-burning wastes. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Amp: A modular approach to machine learning in atomistic simulations

    NASA Astrophysics Data System (ADS)

    Khorshidi, Alireza; Peterson, Andrew A.

    2016-10-01

    Electronic structure calculations, such as those employing Kohn-Sham density functional theory or ab initio wavefunction theories, have allowed for atomistic-level understandings of a wide variety of phenomena and properties of matter at small scales. However, the computational cost of electronic structure methods drastically increases with length and time scales, which makes these methods difficult for long time-scale molecular dynamics simulations or large-sized systems. Machine-learning techniques can provide accurate potentials that can match the quality of electronic structure calculations, provided sufficient training data. These potentials can then be used to rapidly simulate large and long time-scale phenomena at similar quality to the parent electronic structure approach. Machine-learning potentials usually take a bias-free mathematical form and can be readily developed for a wide variety of systems. Electronic structure calculations have favorable properties-namely that they are noiseless and targeted training data can be produced on-demand-that make them particularly well-suited for machine learning. This paper discusses our modular approach to atomistic machine learning through the development of the open-source Atomistic Machine-learning Package (Amp), which allows for representations of both the total and atom-centered potential energy surface, in both periodic and non-periodic systems. Potentials developed through the atom-centered approach are simultaneously applicable for systems with various sizes. Interpolation can be enhanced by introducing custom descriptors of the local environment. We demonstrate this in the current work for Gaussian-type, bispectrum, and Zernike-type descriptors. Amp has an intuitive and modular structure with an interface through the python scripting language yet has parallelizable fortran components for demanding tasks; it is designed to integrate closely with the widely used Atomic Simulation Environment (ASE), which makes it compatible with a wide variety of commercial and open-source electronic structure codes. We finally demonstrate that the neural network model inside Amp can accurately interpolate electronic structure energies as well as forces of thousands of multi-species atomic systems.

  15. Enhanced reduction of an azo dye using henna plant biomass as a solid-phase electron donor, carbon source, and redox mediator.

    PubMed

    Huang, Jingang; Chu, Shushan; Chen, Jianjun; Chen, Yi; Xie, Zhengmiao

    2014-06-01

    The multiple effects of henna plant biomass as a source of carbon, electron donor, and redox mediator (RM) on the enhanced bio-reduction of Orange II (AO7) were investigated. The results indicated that the maximum AO7 reduction rate in the culture with henna powder was ∼6-fold that in the sludge control culture lacking henna. On the one hand, AO7 reduction can be advantageously enhanced by the release of available electron donors; on the other hand, the associated lawsone can act as a fixed RM and play a potential role in shuttling electrons from the released electron donors to the final electron acceptor, AO7. The soluble chemical oxygen demand (SCOD) during each experiment and the FTIR spectra suggested that the weakened AO7 reduction along with the retention of henna powder might not be attributed to the lack of fixed lawsone but rather to the insufficiency of electron donors. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Electricity-driven metabolic shift through direct electron uptake by electroactive heterotroph Clostridium pasteurianum

    PubMed Central

    Choi, Okkyoung; Kim, Taeyeon; Woo, Han Min; Um, Youngsoon

    2014-01-01

    Although microbes directly accepting electrons from a cathode have been applied for CO2 reduction to produce multicarbon-compounds, a high electron demand and low product concentration are critical limitations. Alternatively, the utilization of electrons as a co-reducing power during fermentation has been attempted, but there must be exogenous mediators due to the lack of an electroactive heterotroph. Here, we show that Clostridium pasteurianum DSM 525 simultaneously utilizes both cathode and substrate as electron donors through direct electron transfer. In a cathode compartment poised at +0.045 V vs. SHE, a metabolic shift in C. pasteurianum occurs toward NADH-consuming metabolite production such as butanol from glucose (20% shift in terms of NADH consumption) and 1,3-propandiol from glycerol (21% shift in terms of NADH consumption). Notably, a small amount of electron uptake significantly induces NADH-consuming pathways over the stoichiometric contribution of the electrons as reducing equivalents. Our results demonstrate a previously unknown electroactivity and metabolic shift in the biochemical-producing heterotroph, opening up the possibility of efficient and enhanced production of electron-dense metabolites using electricity. PMID:25376371

  17. Direction of CRT waste glass processing: electronics recycling industry communication.

    PubMed

    Mueller, Julia R; Boehm, Michael W; Drummond, Charles

    2012-08-01

    Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, and the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Characterization of stormwater discharges from Las Flores Industrial Park, Rio Grande, Puerto Rico, 1998-99

    USGS Publications Warehouse

    Rodriguez, Jose M.

    2000-01-01

    Stormwater discharges from Las Flores Industrial Park, Rio Grande, Puerto Rico, were characterized from June 1998 to July 1999 by measuring the flow rate at two outfalls, delineating the drainage areas for each outfall, and calculating the volume of the stormwater discharges. Stormwater-discharge samples were collected and analyzed to determine the quality of the discharges. Constituent loads and loads per area were estimated for each drainage area. The studied drainage subareas covered approximately 46 percent of the total area of the Las Flores Industrial Park. Industrial groups represented in the study areas include manufacturers of textile, electronics, paper, fabricated metal, plastic, and chemical products. The concentrations of oil and grease (1 to 6 milligrams per liter), biochemical oxygen demand (4.7 to 16 milligrams per liter), total organic carbon (5.8 to 36 milligrams per liter), total suspended solids (28 to 100 milligrams per liter), and total phosphorous (0.11 to 0.78 milligrams per liter) from all the samples collected were less than the U.S. Environmental Protection Agency stormwater benchmark concentrations. Concentrations of chemical oxygen demand (15.8 to 157 milligrams per liter) and nitrate and nitrite (0.06 to 1.75 milligrams per liter) exceeded benchmark concentrations at one of the studied drainage areas. Total Kjeldahl nitrogen concentrations (1.00 to 3.20 milligrams per liter) exceeded the benchmark concentrations at the two studied drainage areas. Maximum concentrations for oil and grease, biochemical oxygen demand, chemical oxygen demand, total organic carbon, total Kjeldahl nitrogen, nitrate plus nitrite, and total phosphorous were detected in an area where electronics, plastics, and chemical products are currently manufactured. The maximum concentration of total suspended solids was detected at an area where textile, paper, plastic, chemical, and fabricated metal products are manufactured.

  19. Tutoring Group Learning at a Distance.

    ERIC Educational Resources Information Center

    Fahraeus, Eva R.

    Experiences from a distance course conducted during 1996-97 for high-school teachers in Sweden and reports from other experiments have yielded the conclusion that collaborating via electronic conferencing systems demands new communication patterns. This paper uses theories about communication, group processes, and shared symbolic order and social…

  20. Public Libraries: Responding to Demand.

    ERIC Educational Resources Information Center

    Annichiarico, Mark; And Others

    1993-01-01

    Discussion of problems library wholesalers/distributors face trying to fulfill public libraries' needs while adjusting to a changing industry is based on responses by librarians to a survey on library jobbers. Increased services to libraries, electronic ordering, timeliness, stock management, and quality control are addressed; and a chart of…

  1. WET sensor performance in organic and inorganic media with heterogeneous moisture distribution

    USDA-ARS?s Scientific Manuscript database

    Interest in electronic monitoring of soil water has grown as increased demand for water creates a greater need for effective water management. Relatively inexpensive commercial soil water sensors that use measured dielectric properties to calculate water content, have been developed to address this...

  2. Out of Print

    ERIC Educational Resources Information Center

    Waters, John K.

    2007-01-01

    When Anita Givens, who serves the Texas Education Agency (TEA) as the senior director for instructional materials and educational technology, first began teaching elementary school students to use computers back in the mid-1980s, there were few digital learning materials available and little demand for electronic textbooks. In fact, parents and…

  3. State-of-the-Art Opportunities. Hispanic Special Report: Careers in Engineering.

    ERIC Educational Resources Information Center

    Heller, Michele

    1992-01-01

    Although the demand for electrical, defense, and computer science engineers has dropped sharply, opportunities exist for Hispanics in computer communication and integration, miniaturization of electronic components, environmental, and genetic and biomedical engineering. Engineers should diversify their skills to adapt to the changing field. (KS)

  4. Metastable Polymers for On Demand Transient Electronic Packaging

    DTIC Science & Technology

    2018-01-17

    a triggerable polymer for engineering applications. 25 Approved for public release; distribution is unlimited. 6 REFERENCES (1) Aso, C.; Tagami, S...R. Advanced Materials 2014, 26, 7637. (4) Ito, H.; Willson, C. G. Polymer Engineering & Science 1983, 23, 1012. (5) Ito, H.; England, W. P.; Ueda, M

  5. M-Learning Systems Design--Technology and Pedagogy Aspects

    ERIC Educational Resources Information Center

    Gourova, Elissaveta; Asenova, Asya; Dulev, Pavlin

    2013-01-01

    Technology developments face universities with many challenges--to integrate technologies in educational processes, design new electronic materials, change teaching styles, and better meet the demands of the technology-savvy generation. The paper considers problems of m-learning adoption in Bulgaria at one Faculty of the Technical…

  6. 21 CFR 1005.23 - Bonds.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... IMPORTATION OF ELECTRONIC PRODUCTS Bonding and Compliance Procedures § 1005.23 Bonds. The bond required under... governing its admission into the commerce of the United States upon demand of the District Director of Customs and containing a provision for the performance of any action necessary to bring the product into...

  7. Tools for the Future of Nuclear Physics

    NASA Astrophysics Data System (ADS)

    Geesaman, Donald

    2014-03-01

    The challenges of Nuclear Physics, especially in understanding strongly interacting matter in all its forms in the history of the universe, place ever higher demands on the tools of the field, including the workhorse, accelerators. These demands are not just higher energy and higher luminosity. To recreate the matter that fleetingly was formed in the origin of the heavy elements, we need higher power heavy-ion accelerators and creative techniques to harvest the isotopes. We also need high-current low-energy accelerators deep underground to detect the very slow rate reactions in stellar burning. To explore the three dimensional distributions of high-momentum quarks in hadrons and to search for gluonic excitations we need high-current CW electron accelerators. Understanding the gluonic structure of nuclei and the three dimensional distributions of partons at lower x, we need high-luminosity electron-ion colliders that also have the capabilities to prepare, preserve and manipulate the polarization of both beams. A search for the critical point in the QCD phase diagram demands high luminosity beams over a broad range of species and energy. With advances in cavity design and construction, beam manipulation and cooling, and ion sources and targets, the Nuclear Physics community, in the U.S. and internationally has a coordinated vision to deliver this exciting science. This work is supported by DOE, Office of Nuclear Physics, under contract DE-AC02-06CH11357.

  8. Semi-Automated Diagnosis, Repair, and Rework of Spacecraft Electronics

    NASA Technical Reports Server (NTRS)

    Struk, Peter M.; Oeftering, Richard C.; Easton, John W.; Anderson, Eric E.

    2008-01-01

    NASA's Constellation Program for Exploration of the Moon and Mars places human crews in extreme isolation in resource scarce environments. Near Earth, the discontinuation of Space Shuttle flights after 2010 will alter the up- and down-mass capacity for the International Space Station (ISS). NASA is considering new options for logistics support strategies for future missions. Aerospace systems are often composed of replaceable modular blocks that minimize the need for complex service operations in the field. Such a strategy however, implies a robust and responsive logistics infrastructure with relatively low transportation costs. The modular Orbital Replacement Units (ORU) used for ISS requires relatively large blocks of replacement hardware even though the actual failed component may really be three orders of magnitude smaller. The ability to perform in-situ repair of electronics circuits at the component level can dramatically reduce the scale of spares and related logistics cost. This ability also reduces mission risk, increases crew independence and improves the overall supportability of the program. The Component-Level Electronics Assembly Repair (CLEAR) task under the NASA Supportability program was established to demonstrate the practicality of repair by first investigating widely used soldering materials and processes (M&P) performed by modest manual means. The work will result in program guidelines for performing manual repairs along with design guidance for circuit reparability. The next phase of CLEAR recognizes that manual repair has its limitations and some highly integrated devices are extremely difficult to handle and demand semi-automated equipment. Further, electronics repairs require a broad range of diagnostic capability to isolate the faulty components. Finally repairs must pass functional tests to determine that the repairs are successful and the circuit can be returned to service. To prevent equipment demands from exceeding spacecraft volume capacity and skill demands from exceeding crew time and training limits, the CLEAR project is examining options provided by non-real time tele-operations, robotics, and a new generation of diagnostic equipment. This paper outlines a strategy to create an effective repair environment where, with the support of ground based engineers, crewmembers can diagnose, repair and test flight electronics in-situ. This paper also discusses the implications of successful tele-robotic repairs when expanded to rework and reconfiguration of used flight assets for building Constellation infrastructure elements.

  9. Substrate Effects for Atomic Chain Electronics

    NASA Technical Reports Server (NTRS)

    Yamada, Toshishige; Saini, Subhash (Technical Monitor)

    1998-01-01

    A substrate for future atomic chain electronics, where adatoms are placed at designated positions and form atomically precise device components, is studied theoretically. The substrate has to serve as a two-dimensional template for adatom mounting with a reasonable confinement barrier and also provide electronic isolation, preventing unwanted coupling between independent adatom structures. For excellent structural stability, we demand chemical bonding between the adatoms and substrate atoms, but then good electronic isolation may not be guaranteed. Conditions are clarified for good isolation. Because of the chemical bonding, fundamental adatom properties are strongly influenced: a chain with group IV adatoms having two chemical bonds, or a chain with group III adatoms having one chemical bond is semiconducting. Charge transfer from or to the substrate atoms brings about unintentional doping, and the electronic properties have to be considered for the entire combination of the adatom and substrate systems even if the adatom modes are well localized at the surface.

  10. Energy-loss return gate via liquid dielectric polarization.

    PubMed

    Kim, Taehun; Yong, Hyungseok; Kim, Banseok; Kim, Dongseob; Choi, Dukhyun; Park, Yong Tae; Lee, Sangmin

    2018-04-12

    There has been much research on renewable energy-harvesting techniques. However, owing to increasing energy demands, significant energy-related issues remain to be solved. Efforts aimed at reducing the amount of energy loss in electric/electronic systems are essential for reducing energy consumption and protecting the environment. Here, we design an energy-loss return gate system that reduces energy loss from electric/electronic systems by utilizing the polarization of liquid dielectrics. The use of a liquid dielectric material in the energy-loss return gate generates electrostatic potential energy while reducing the dielectric loss of the electric/electronic system. Hence, an energy-loss return gate can make breakthrough impacts possible by amplifying energy-harvesting efficiency, lowering the power consumption of electronics, and storing the returned energy. Our study indicates the potential for enhancing energy-harvesting technologies for electric/electronics systems, while increasing the widespread development of these systems.

  11. Lithium-Ion Technology for Aerospace Applications- Advancing Battery Management Electronics

    NASA Astrophysics Data System (ADS)

    Gitzendanner, R.; Jones, E.; Deory, C.; Carmen, D.

    2005-05-01

    Lithium-ion technology offers a unique, weight and volume saving, solution to the power storage needs of space applications. With higher energy and power densities than conventional technologies, such as Nickel-Hydrogen (Ni-H) and Nickel/Cadmium (Ni- Cd), and comparable cycle life and reliability, Lithium-ion technology is gaining interest in many space applications. As the demand for Lithium-ion batteries with high reliability and long life increases, the need for battery management electronics, including individual cell balancing and monitoring, becomes apparent. With onboard electronics, the cells are monitored individually, and are protected from over charge or over discharge by way of integral protection circuitry. State of Charge, State of Health and other useful telemetry can also be calculated by the integrated electronics and reported to the application. Lab-based, and real-life, testing and use of these battery systems has shown the advantages of an integrated electronics package.

  12. Electron temperature diagnostics of aluminium plasma in a z-pinch experiment at the “QiangGuang-1" facility

    NASA Astrophysics Data System (ADS)

    Li, Mo; Wu, Jian; Wang, Liang-Ping; Wu, Gang; Han, Juan-Juan; Guo, Ning; Qiu, Meng-Tong

    2012-12-01

    Two curved crystal spectrometers are set up on the “QiangGuang-1" generator to measure the z-pinch plasma spectra emitted from planar aluminum wire array loads. Kodak Biomax-MS film and an IRD AXUVHS5# array are employed to record time-integrated and time-resolved free-bound radiation, respectively. The photon energy recorded by each detector is ascertained by using the L-shell lines of molybdenum plasma. Based on the exponential relation between the continuum power and photon energies, the aluminum plasma electron temperatures are measured. For the time-integrated diagnosis, several “bright spots" indicate electron temperatures between (450 eV ~ 520 eV) ± 35%. And for the time-resolved ones, the result shows that the electron temperature reaches about 800 eV ± 30% at peak power. The system satisfies the demand of z-pinch plasma electron temperature diagnosis on a ~ 1 MA facility.

  13. Toward all-carbon electronics: fabrication of graphene-based flexible electronic circuits and memory cards using maskless laser direct writing.

    PubMed

    Liang, Jiajie; Chen, Yongsheng; Xu, Yanfei; Liu, Zhibo; Zhang, Long; Zhao, Xin; Zhang, Xiaoliang; Tian, Jianguo; Huang, Yi; Ma, Yanfeng; Li, Feifei

    2010-11-01

    Owing to its extraordinary electronic property, chemical stability, and unique two-dimensional nanostructure, graphene is being considered as an ideal material for the highly expected all-carbon-based micro/nanoscale electronics. Herein, we present a simple yet versatile approach to constructing all-carbon micro/nanoelectronics using solution-processing graphene films directly. From these graphene films, various graphene-based microcosmic patterns and structures have been fabricated using maskless computer-controlled laser cutting. Furthermore, a complete system involving a prototype of a flexible write-once-read-many-times memory card and a fast data-reading system has been demonstrated, with infinite data retention time and high reliability. These results indicate that graphene could be the ideal material for fabricating the highly demanded all-carbon and flexible devices and electronics using the simple and efficient roll-to-roll printing process when combined with maskless direct data writing.

  14. Electrochemical electron beam lithography: Write, read, and erase metallic nanocrystals on demand

    PubMed Central

    Park, Jeung Hun; Steingart, Daniel A.; Kodambaka, Suneel; Ross, Frances M.

    2017-01-01

    We develop a solution-based nanoscale patterning technique for site-specific deposition and dissolution of metallic nanocrystals. Nanocrystals are grown at desired locations by electron beam–induced reduction of metal ions in solution, with the ions supplied by dissolution of a nearby electrode via an applied potential. The nanocrystals can be “erased” by choice of beam conditions and regrown repeatably. We demonstrate these processes via in situ transmission electron microscopy using Au as the model material and extend to other metals. We anticipate that this approach can be used to deposit multicomponent alloys and core-shell nanostructures with nanoscale spatial and compositional resolutions for a variety of possible applications. PMID:28706992

  15. Shape Memory Polymers for Body Motion Energy Harvesting and Self-Powered Mechanosensing.

    PubMed

    Liu, Ruiyuan; Kuang, Xiao; Deng, Jianan; Wang, Yi-Cheng; Wang, Aurelia C; Ding, Wenbo; Lai, Ying-Chih; Chen, Jun; Wang, Peihong; Lin, Zhiqun; Qi, H Jerry; Sun, Baoquan; Wang, Zhong Lin

    2018-02-01

    Growing demand in portable electronics raises a requirement to electronic devices being stretchable, deformable, and durable, for which functional polymers are ideal choices of materials. Here, the first transformable smart energy harvester and self-powered mechanosensation sensor using shape memory polymers is demonstrated. The device is based on the mechanism of a flexible triboelectric nanogenerator using the thermally triggered shape transformation of organic materials for effectively harvesting mechanical energy. This work paves a new direction for functional polymers, especially in the field of mechanosensation for potential applications in areas such as soft robotics, biomedical devices, and wearable electronics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Correlated electron-nuclear dynamics with conditional wave functions.

    PubMed

    Albareda, Guillermo; Appel, Heiko; Franco, Ignacio; Abedi, Ali; Rubio, Angel

    2014-08-22

    The molecular Schrödinger equation is rewritten in terms of nonunitary equations of motion for the nuclei (or electrons) that depend parametrically on the configuration of an ensemble of generally defined electronic (or nuclear) trajectories. This scheme is exact and does not rely on the tracing out of degrees of freedom. Hence, the use of trajectory-based statistical techniques can be exploited to circumvent the calculation of the computationally demanding Born-Oppenheimer potential-energy surfaces and nonadiabatic coupling elements. The concept of the potential-energy surface is restored by establishing a formal connection with the exact factorization of the full wave function. This connection is used to gain insight from a simplified form of the exact propagation scheme.

  17. Control technology for future aircraft propulsion systems

    NASA Technical Reports Server (NTRS)

    Zeller, J. R.; Szuch, J. R.; Merrill, W. C.; Lehtinen, B.; Soeder, J. F.

    1984-01-01

    The need for a more sophisticated engine control system is discussed. The improvements in better thrust-to-weight ratios demand the manipulation of more control inputs. New technological solutions to the engine control problem are practiced. The digital electronic engine control (DEEC) system is a step in the evolution to digital electronic engine control. Technology issues are addressed to ensure a growth in confidence in sophisticated electronic controls for aircraft turbine engines. The need of a control system architecture which permits propulsion controls to be functionally integrated with other aircraft systems is established. Areas of technology studied include: (1) control design methodology; (2) improved modeling and simulation methods; and (3) implementation technologies. Objectives, results and future thrusts are summarized.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ianakiev, Kiril Dimitrov; Iliev, Metodi; Swinhoe, Martyn Thomas

    The KM200 device is a versatile, configurable front-end electronics boards that can be used as a functional replacement for Canberra’s JAB-01 boards based on the Amptek A-111 hybrid chip, which continues to be the preferred choice of electronics for large number of the boards in junction boxes of multiplicity counters that process the signal from an array of 3He detectors. Unlike the A-111 chip’s fixed time constants and sensitivity range, the shaping time and sensitivity of the new KM200 can be optimized for demanding applications such as spent fuel, and thus could improve the safeguards measurements of existing systems wheremore » the A-111 or PDT electronics does not perform well.« less

  19. National Tree Climbing Guide [2015 Electronic Edition

    Treesearch

    Jerry Berdeen; Burnham Chamberlain; Teryl Grubb; Art Henderson; Brock Mayo; Manfred Mielke; Kathryn Purcell; Dennis Ringnes; Marc Roberts; Donna Stubbs; Micah Thorning

    2015-01-01

    The Forest Service Tree Climbing Program provides direction that protects Forest Service employees while ascending, descending, and working aloft in trees by establishing national direction based on recognized industry standards, procedures and practices. Climbing and working in trees demands specialized equipment and skills. The potential for a serious injury or fatal...

  20. A Proposed Design for the Business Capstone Course with Emphasis on Improving Students' Information Competency

    ERIC Educational Resources Information Center

    Gilinsky, Armand, Jr.; Robison, Richard

    2008-01-01

    Business school accrediting agencies and employers increasingly demand evidence that students are mastering information competency (IC) skills. The authors present an innovative approach to inculcate IC skills in the strategic management "capstone" class, integrating cross-departmental student training in using electronic information sources,…

  1. ENGINEERING TRADE-OFFS (ETO) INITIATIVE FOR REDUCTION IN MERCURY USE (SYSTEMS ANALYSIS BRANCH, SUSTAINABLE TECHNOLOGY DIVISION,NRMRL)

    EPA Science Inventory

    The demand for mercury in the United States is still growing or declining only slightly in a number of industrial sectors. These include electric lighting, electronic equipment, wiring devices and switches, measurement and control instruments, dental equipment and supplies, labor...

  2. Finding Possibility and Probability Lessons in Sports

    ERIC Educational Resources Information Center

    Busadee, Nutjira; Laosinchai, Parames; Panijpan, Bhinyo

    2011-01-01

    Today's students demand that their lessons be real, interesting, relevant, and manageable. Mathematics is one subject that eludes many students partly because its traditional presentation lacks those elements that encourage students to learn. Easy accessibility through electronic media has exposed people all over the world to a variety of sports…

  3. Librarianship: The Challenge of the Information and Electronic Revolution.

    ERIC Educational Resources Information Center

    Dunstan, Peter

    Librarians need to take the initiative and seize the opportunities presented by a changing environment and society's demands for greater access to information. New technologies such as laser disks, machine indexing, telefacsimile, microcomputer applications, and fiber optics are having an immense impact on the practice of librarianship, and the…

  4. Perspiration Thresholds and Secure Suspension for Lower Limb Amputees in Demanding Environments

    DTIC Science & Technology

    2015-10-01

    VAPSHCS) site, fabricating custom, moisture-wicking textile sock with a proximal elastomeric seal, fabricating prosthetic sockets, fabricating electronic...Aims: This research has two specific aims: (1) determine if lower limb amputees are willing to use smart activity monitors as part of their daily life

  5. Activity Theory Framework and Cognitive Perspectives in Designing Technology-Based Support Systems.

    ERIC Educational Resources Information Center

    Sheu, Feng-Ru

    With the increased demand and interest in electronic performance support systems (EPSS), particularly for supporting knowledge-based problems solving expertise in the information age (Gustafson, 2000; Dickelman, 2000; Kasvi & Vartiainen, 2000), instructional designers are facing a new challenge designing a system that could deliver (or…

  6. Industrial Ceramics: Secondary Schools.

    ERIC Educational Resources Information Center

    New York City Board of Education, Brooklyn, NY. Bureau of Curriculum Development.

    The expanding use of ceramic products in today's world can be seen in the areas of communications, construction, aerospace, textiles, metallurgy, atomic energy, and electronics. The demands of science have brought ceramics from an art to an industry using mass production and automated processes which requires the services of great numbers as the…

  7. The frequency spectrum crisis - Issues and answers

    NASA Astrophysics Data System (ADS)

    Armes, G. L.

    The frequency spectrum represents a unique resource which can be overtaxed. In the present investigation, it is attempted to evalute the demand for satellite and microwave services. Dimensions of increased demand are discussed, taking into account developments related to the introduction of the personal computer, the activities of the computer and communications industries in preparation for the office of the future, and electronic publishing. Attention is given to common carrier spectrum congestion, common carrier microwave, satellite communications, teleports, international implications, satellite frequency bands, satellite spectrum implications, alternatives regarding the utilization of microwave frequency bands, U.S. Government spectrum utilization, and the impact at C-band.

  8. Multi-time scale dynamics in power electronics-dominated power systems

    NASA Astrophysics Data System (ADS)

    Yuan, Xiaoming; Hu, Jiabing; Cheng, Shijie

    2017-09-01

    Electric power infrastructure has recently undergone a comprehensive transformation from electromagnetics to semiconductors. Such a development is attributed to the rapid growth of power electronic converter applications in the load side to realize energy conservation and on the supply side for renewable generations and power transmissions using high voltage direct current transmission. This transformation has altered the fundamental mechanism of power system dynamics, which demands the establishment of a new theory for power system control and protection. This paper presents thoughts on a theoretical framework for the coming semiconducting power systems.

  9. AGARD Flight Test Techniques Series. Volume 17. Electronic Warfare Test and Evaluation. (Les Essais et l’Evaluation du Materiel de Guerre Electronique)

    DTIC Science & Technology

    2000-03-01

    FRIENDLY DR ENEMY PLOY OFOR DEGSRADING, ENEUTALY IG DEGRA E,’ EUTRALIE, OR DESTR Y concepts, procedures, and techniques that apply generically to CMA...Association of Old Crows, September 1984 Price, Alfred, "The History of Electronic Warfare," Volume 2, Association of Old Crows, October 1989 Claxton, John...Canada Les demandes de documents RTO ou AGARD doivent comporter la denomination "RTO" ou "AGARD" selon le cas, suivie du numdro de s~rie (par exemple

  10. Electron storage in single wall carbon nanotubes. Fermi level equilibration in semiconductor-SWCNT suspensions.

    PubMed

    Kongkanand, Anusorn; Kamat, Prashant V

    2007-08-01

    The use of single wall carbon nanotubes (SWCNTs) as conduits for transporting electrons in a photoelectrochemical solar cell and electronic devices requires better understanding of their electron-accepting properties. When in contact with photoirradiated TiO(2) nanoparticles, SWCNTs accept and store electrons. The Fermi level equilibration with photoirradiated TiO(2) particles indicates storage of up to 1 electron per 32 carbon atoms in the SWCNT. The stored electrons are readily discharged on demand upon addition of electron acceptors such as thiazine and oxazine dyes (reduction potential less negative than that of the SWCNT conduction band) to the TiO(2)-SWCNT suspension. The stepwise electron transfer from photoirradiated TiO(2) nanoparticles --> SWCNT --> redox couple has enabled us to probe the electron equilibration process and determine the apparent Fermi level of the TiO(2)-SWCNT system. A positive shift in apparent Fermi level (20-30 mV) indicates the ability of SWCNTs to undergo charge equilibration with photoirradiated TiO(2) particles. The dependence of discharge capacity on the reduction potential of the dye redox couple is compared for TiO(2) and TiO(2)-SWCNT systems under equilibration conditions.

  11. Strong confinement-induced engineering of the g factor and lifetime of conduction electron spins in Ge quantum wells

    PubMed Central

    Giorgioni, Anna; Paleari, Stefano; Cecchi, Stefano; Vitiello, Elisa; Grilli, Emanuele; Isella, Giovanni; Jantsch, Wolfgang; Fanciulli, Marco; Pezzoli, Fabio

    2016-01-01

    Control of electron spin coherence via external fields is fundamental in spintronics. Its implementation demands a host material that accommodates the desirable but contrasting requirements of spin robustness against relaxation mechanisms and sizeable coupling between spin and orbital motion of the carriers. Here, we focus on Ge, which is a prominent candidate for shuttling spin quantum bits into the mainstream Si electronics. So far, however, the intrinsic spin-dependent phenomena of free electrons in conventional Ge/Si heterojunctions have proved to be elusive because of epitaxy constraints and an unfavourable band alignment. We overcome these fundamental limitations by investigating a two-dimensional electron gas in quantum wells of pure Ge grown on Si. These epitaxial systems demonstrate exceptionally long spin lifetimes. In particular, by fine-tuning quantum confinement we demonstrate that the electron Landé g factor can be engineered in our CMOS-compatible architecture over a range previously inaccessible for Si spintronics. PMID:28000670

  12. A BSc level option in biomedical electronics.

    PubMed

    Gergely, S

    1979-01-01

    1. The application of electronic instruments in medical diagnosis and therapy is well established. 2. There is a demand for electronic engineers both in industry and in the Health Service at all ranges of educational attainment. 3. It is possible to identify a set of objectives for a first degree course in Biomedical Electronics. An important element of this course should be the provision of practical experience in industry and in hospitals. 4. Such courses are available both in Europe and in the United States. Although the postgraduate course provision was satisfactory in the UK in the early seventies, only one full time undergraduate course was in operation. 5. A sandwich course can be designed in Biomedical Electronics as a major option of an existing BSc course in Electrical and Electronic Engineering. Provision can be made for entering and leaving the option. The option can be arranged to follow the guidelines laid down by the IEE for exemption from its educational requirements. 6. The option described started at the Lanchester Polytechnic in Coventry in September 1977.

  13. Precision determination of electron scattering angle by differential nuclear recoil energy method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liyanage, N.; Saenboonruang, K.

    2015-12-01

    The accurate determination of the scattered electron angle is crucial to electron scattering experiments, both with open-geometry large-acceptance spectrometers and ones with dipole-type magnetic spectrometers for electron detection. In particular, for small central-angle experiments using dipole-type magnetic spectrometers, in which surveys are used to measure the spectrometer angle with respect to the primary electron beam, the importance of the scattering angle determination is emphasized. However, given the complexities of large experiments and spectrometers, the accuracy of such surveys is limited and insufficient to meet demands of some experiments. In this article, we present a new technique for determination of themore » electron scattering angle based on an accurate measurement of the primary beam energy and the principle of differential nuclear recoil. This technique was used to determine the scattering angle for several experiments carried out at the Experimental Hall A, Jefferson Lab. Results have shown that the new technique greatly improved the accuracy of the angle determination compared to surveys.« less

  14. Precision Determination of Electron Scattering Angle by Differential Nuclear Recoil Energy Method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liyanage, Nilanga; Saenboonruang, Kiadtisak

    2015-09-01

    The accurate determination of the scattered electron angle is crucial to electron scattering experiments, both with open-geometry large-acceptance spectrometers and ones with dipole-type magnetic spectrometers for electron detection. In particular, for small central-angle experiments using dipole-type magnetic spectrometers, in which surveys are used to measure the spectrometer angle with respect to the primary electron beam, the importance of the scattering angle determination is emphasized. However, given the complexities of large experiments and spectrometers, the accuracy of such surveys is limited and insufficient to meet demands of some experiments. In this article, we present a new technique for determination of themore » electron scattering angle based on an accurate measurement of the primary beam energy and the principle of differential nuclear recoil. This technique was used to determine the scattering angle for several experiments carried out at the Experimental Hall A, Jefferson Lab. Results have shown that the new technique greatly improved the accuracy of the angle determination compared to surveys.« less

  15. The impact of health information technology and e-health on the future demand for physician services.

    PubMed

    Weiner, Jonathan P; Yeh, Susan; Blumenthal, David

    2013-11-01

    Arguably, few factors will change the future face of the American health care workforce as widely and dramatically as health information technology (IT) and electronic health (e-health) applications. We explore how such applications designed for providers and patients will affect the future demand for physicians. We performed what we believe to be the most comprehensive review of the literature to date, including previously published systematic reviews and relevant individual studies. We estimate that if health IT were fully implemented in 30 percent of community-based physicians' offices, the demand for physicians would be reduced by about 4-9 percent. Delegation of care to nurse practitioners and physician assistants supported by health IT could reduce the future demand for physicians by 4-7 percent. Similarly, IT-supported delegation from specialist physicians to generalists could reduce the demand for specialists by 2-5 percent. The use of health IT could also help address regional shortages of physicians by potentially enabling 12 percent of care to be delivered remotely or asynchronously. These estimated impacts could more than double if comprehensive health IT systems were adopted by 70 percent of US ambulatory care delivery settings. Future predictions of physician supply adequacy should take these likely changes into account.

  16. Response of Bean (Vicia faba L.) Plants to Low Sink Demand by Measuring the Gas Exchange Rates and Chlorophyll a Fluorescence Kinetics

    PubMed Central

    Liu, Guo-Tian; Xu, Hong-Guo; Wang, Li-Jun; Li, Shao-Hua

    2013-01-01

    Background The decline of photosynthesis in plants under low sink demand is well known. Previous studies focused on the relationship between stomatal conductance (g s) and net photosynthetic rate (P n). These studies investigated the effect of changes in Photosystem II (PSII) function on the P n decline under low sink demand. However, little is known about its effects on different limiting steps of electron transport chain in PSII under this condition. Methodology/Principal Finding Two-month-old bean plants were processed by removing pods and flowers (low sink demand). On the 1st day after low sink demand treatment, a decline of P n was accompanied by a decrease in g s and internal-to-ambient CO2 concentration ratio (C i/C a). From the 3rd to 9th day, P n and g s declined continuously while C i/C a ratio remained stable in the treatment. Moreover, these values were lower than that of control. Wk (a parameter reflecting the damage to oxygen evolving complex of the donor side of PSII) values in the treatment were significantly higher than their corresponding control values. However, RCQA (a parameter reflecting the number of active RCs per excited cross-section of PSII) values in the treatment were significantly lower than control from the 5th day. From the 11th to 21st day, P n and g s of the treatment continued to decline and were lower than control. This was accompanied by a decrease of RCQA, and an increase of Wk. Furthermore, the quantum yield parameters φ Po, φ Eo and ψ Eo in the treatment were lower than in control; however, C i/C a values in the treatment gradually increased and were significantly higher than control on the 21st day. Conclusions Stomatal limitation during the early stage, whereas a combination of stomatal and non-stomatal limitation during the middle stage might be responsible for the reduction of P n under low sink demand. Non-stomatal limitation during the late stages after the removal of the sink of roots and pods may also cause P n reduction. The non-stomatal limitation was associated with the inhibition of PSII electron transport chain. Our data suggests that the donor side of PSII was the most sensitive to low sink demand followed by the reaction center of PSII. The acceptor side of PSII may be the least sensitive. PMID:24324626

  17. Managing demand for laboratory tests: a laboratory toolkit.

    PubMed

    Fryer, Anthony A; Smellie, W Stuart A

    2013-01-01

    Healthcare budgets worldwide are facing increasing pressure to reduce costs and improve efficiency, while maintaining quality. Laboratory testing has not escaped this pressure, particularly since pathology investigations cost the National Health Service £2.5 billion per year. Indeed, the Carter Review, a UK Department of Health-commissioned review of pathology services in England, estimated that 20% of this could be saved by improving pathology services, despite an average annual increase of 8%-10% in workload. One area of increasing importance is managing the demands for pathology tests and reducing inappropriate requesting. The Carter Review estimated that 25% of pathology tests were unnecessary, representing a huge potential waste. Certainly, the large variability in levels of requesting between general practitioners suggests that inappropriate requesting is widespread. Unlocking the key to this variation and implementing measures to reduce inappropriate requesting would have major implications for patients and healthcare resources alike. This article reviews the approaches to demand management. Specifically, it aims to (a) define demand management and inappropriate requesting, (b) assess the drivers for demand management, (c) examine the various approaches used, illustrating the potential of electronic requesting and (d) provide a wider context. It will cover issues, such as educational approaches, information technology opportunities and challenges, vetting, duplicate request identification and management, the role of key performance indicators, profile composition and assessment of downstream impact of inappropriate requesting. Currently, many laboratories are exploring demand management using a plethora of disparate approaches. Hence, this review seeks to provide a 'toolkit' with the view to allowing laboratories to develop a standardised demand management strategy.

  18. Charge transport, interfacial interactions and synergistic mechanisms in BiNbO4/MWO4 (M = Zn and Cd) heterostructures for hydrogen production: insights from a DFT+U study.

    PubMed

    Opoku, Francis; Kuben Govender, Krishna; van Sittert, Cornelia Gertina Catharina Elizabeth; Poomani Govender, Penny

    2017-10-25

    In the 21st century, the growing demand of global energy is one of the key challenges. The photocatalytic generation of hydrogen has attracted extensive attention to discuss the increasing global demand for sustainable and clean energy. However, hydrogen evolution reactions normally use the economically expensive rare noble metals and the processes remain a challenge. Herein, low-cost BiNbO 4 /MWO 4 (010) heterostructures are studied for the first time to check their suitability towards photocatalytic hydrogen production. A theoretical study with the aid of density functional theory (DFT) is used to investigate the synergistic effect, ionisation energy, electron affinities, charge transfer, electronic properties and the underlying mechanism for hydrogen generation of BiNbO 4 /MWO 4 (010) heterostructures. The experimental band gaps of bulk ZnWO 4 , CdWO 4 and BiNbO 4 are well reproduced using the DFT+U method. The calculated band edge position shows a type-II staggered band alignment and the charge transfer between BiNbO 4 and MWO 4 monolayers results in a large interfacial built-in potential, which will favour the separation of charge carriers in the heterostructures. The effective mass of the photoinduced holes is higher compared to the electrons, making the heterostructures useful in hydrogen production. The relatively low ionisation energy and electron affinity for the heterostructures compared to the monolayers make them ideal for photocatalysis applications due to their small energy barrier for the injection of electrons and creation of holes. The BiNbO 4 /MWO 4 (010) heterostructures are more suitable for photocatalytic hydrogen production due to their strong reducing power relative to the H + /H 2 O potential. This study sheds light on the less known BiNbO 4 /ZnWO 4 (010) heterostructures and the fully explored electronic and optical properties will pave way for future photocatalytic water splitting applications.

  19. Predicting reactivity of model DOM compounds towards chlorine with mediated electrochemical oxidation.

    PubMed

    de Vera, Glen Andrew; Gernjak, Wolfgang; Radjenovic, Jelena

    2017-05-01

    Chlorine demand of a water sample depends on the characteristics of dissolved organic matter (DOM). It is an important parameter for water utilities used to assess oxidant and/or disinfectant consumption of source waters during treatment and distribution. In this study, model compounds namely resorcinol, tannic acid, vanillin, cysteine, tyrosine, and tryptophan were used to represent the reactive moieties of complex DOM mixtures. The reactivity of these compounds was evaluated in terms of Cl 2 demand and electron donating capacity (EDC). The EDC was determined by mediated electrochemical oxidation (MEO) which involves the use of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) as an electron shuttle. The Cl 2 demand of readily oxidizable compounds (resorcinol, tannic acid, vanillin, and cysteine) was found to correlate well with EDC (R 2  = 0.98). The EDC values (mol e - /mol C) of the model compounds are as follows: 1.18 (cysteine) > 0.77 (resorcinol) > 0.59 (vanillin) > 0.52 (tannic acid) > 0.36 (tryptophan) > 0.19 (tyrosine). To determine the effect of pre-oxidation on EDC, ozone was added (0.1 mol O 3 /mol C) into each model compound solution. Ozonation caused a general decrease in EDC (10-40%), chlorine demand (10-30%), and UV absorbance (10-40%), except for tyrosine which showed both increased UV 275 and EDC. Before and after ozonation, 24 h disinfection byproduct (DBP) formation potential tests (Cl 2 residual = 1.5 mg/L) were conducted to evaluate the use of EDC for DBP formation prediction. The results indicate that there was no significant correlation between the EDC of the model compounds and the formation potentials of adsorbable organic chlorine, trichloromethane, and trichloroacetic acid. This suggests that while EDC correlates with Cl 2 demand, chlorine consumption may not directly translate to DBP formation because oxidation reactions may dominate over substitution reactions. Overall, this study provides useful insights on the reactions of ABTS + and HOCl with model DOM compounds, and highlights the potential application of MEO for rapid determination of Cl 2 demand of a water sample. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Induced superconductivity in high-mobility two-dimensional electron gas in gallium arsenide heterostructures.

    PubMed

    Wan, Zhong; Kazakov, Aleksandr; Manfra, Michael J; Pfeiffer, Loren N; West, Ken W; Rokhinson, Leonid P

    2015-06-11

    Search for Majorana fermions renewed interest in semiconductor-superconductor interfaces, while a quest for higher-order non-Abelian excitations demands formation of superconducting contacts to materials with fractionalized excitations, such as a two-dimensional electron gas in a fractional quantum Hall regime. Here we report induced superconductivity in high-mobility two-dimensional electron gas in gallium arsenide heterostructures and development of highly transparent semiconductor-superconductor ohmic contacts. Supercurrent with characteristic temperature dependence of a ballistic junction has been observed across 0.6 μm, a regime previously achieved only in point contacts but essential to the formation of well separated non-Abelian states. High critical fields (>16 T) in NbN contacts enables investigation of an interplay between superconductivity and strongly correlated states in a two-dimensional electron gas at high magnetic fields.

  1. Induced superconductivity in high-mobility two-dimensional electron gas in gallium arsenide heterostructures

    PubMed Central

    Wan, Zhong; Kazakov, Aleksandr; Manfra, Michael J.; Pfeiffer, Loren N.; West, Ken W.; Rokhinson, Leonid P.

    2015-01-01

    Search for Majorana fermions renewed interest in semiconductor–superconductor interfaces, while a quest for higher-order non-Abelian excitations demands formation of superconducting contacts to materials with fractionalized excitations, such as a two-dimensional electron gas in a fractional quantum Hall regime. Here we report induced superconductivity in high-mobility two-dimensional electron gas in gallium arsenide heterostructures and development of highly transparent semiconductor–superconductor ohmic contacts. Supercurrent with characteristic temperature dependence of a ballistic junction has been observed across 0.6 μm, a regime previously achieved only in point contacts but essential to the formation of well separated non-Abelian states. High critical fields (>16 T) in NbN contacts enables investigation of an interplay between superconductivity and strongly correlated states in a two-dimensional electron gas at high magnetic fields. PMID:26067452

  2. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Joshua, E-mail: joshuk7@uci.edu; Park, Sun-Jun; Nguyen, Thao

    With the growing prominence of wearable electronic technology, there is a need to improve the mechanical reliability of electronics for more demanding applications. Conductive wires represent a vital component present in all electronics. Unlike traditional planar and rigid electronics, these new wearable electrical components must conform to curvilinear surfaces, stretch with the body, and remain unobtrusive and low profile. In this paper, the piezoresistive response of shrink induced wrinkled gold thin films under strain demonstrates robust conductive performance in excess of 200% strain. Importantly, the wrinkled metallic thin films displayed negligible change in resistance of up to 100% strain. Themore » wrinkled metallic wires exhibited consistent performance after repetitive strain. Importantly, these wrinkled thin films are inexpensive to fabricate and are compatible with roll to roll manufacturing processes. We propose that these wrinkled metal thin film wires are an attractive alternative to conventional wires for wearable applications.« less

  3. 80 A/cm2 electron beams from metal targets irradiated by KrCl and XeCl excimer lasers

    NASA Astrophysics Data System (ADS)

    Beloglazov, A.; Martino, M.; Nassisi, V.

    1996-05-01

    Due to the growing demand for high-current and long-duration electron-beam devices, laser electron sources were investigated in our laboratory. Experiments on electron-beam generation and propagation from aluminium and copper targets illuminated by XeCl (308 nm) and KrCl (222 nm) excimer lasers, were carried out under plasma ignition due to laser irradiation. This plasma supplied a spontaneous accelerating electric field of about 370 kV/m without an external accelerating voltage. By applying the modified one-dimensional Poisson equation, we computed the expected current and we also estimated the plasma concentration during the accelerating process. At 40 kV of accelerating voltage, an output current pulse of about 80 A/cm2 was detected from an Al target irradiated by the shorter wavelength laser.

  4. Use of Electronic Resources for Psychiatry Clerkship Learning: A Medical Student Survey.

    PubMed

    Snow, Caitlin E; Torous, John; Gordon-Elliott, Janna S; Penzner, Julie B; Meyer, Fermonta; Boland, Robert

    2017-10-01

    The primary aim of this study is to examine medical students' use patterns, preferences, and perceptions of electronic educational resources available for psychiatry clerkship learning. Eligible participants included medical students who had completed the psychiatry clerkship during a 24-month period. An internet-based questionnaire was used to collect information regarding the outcomes described above. A total of 68 medical students responded to the survey. Most respondents reported high utilization of electronic resources on an array of devices for psychiatry clerkship learning and indicated a preference for electronic over print resources. The most commonly endorsed barriers to the use of electronic resources were that the source contained irrelevant and non-specific content, access was associated with a financial cost, and faculty guidance on recommended resources was insufficient. Respondents indicated a wish for more psychiatry-specific electronic learning resources. The authors' results suggest that a demand exists for high-quality electronic and portable learning tools that are relevant to medical student education in psychiatry. Psychiatry educators are usefully positioned to be involved in the development of such resources.

  5. Electron Matter Optics and the Quantum Electron Stern-Gerlach Magnet

    NASA Astrophysics Data System (ADS)

    McGregor, Scot; Bach, Roger; Yin, Xiaolu; Liou, Sy-Hwang; Batelaan, Herman; Gronniger, Glen

    2011-05-01

    We explore electron interferometry for the purpose of performing fundamental quantum mechanical experiments and sensing applications. To this end electron matter optics elements, in particular, a diffraction limited single slit, a double slit, and a nano-fabricated grating diffraction apparatus as well as a Mach-Zehnder IFM were previously developed. The double slit diffraction pattern has been recorded one electron at a time. Furthermore, the capability of closing each slit on demand has been developed, in that way realizing the thought experiment that Feynman explains in his lectures. The capability of the Mach-Zehnder interferometer to sense DC and AC electromagnetic fields for industrial applications is currently under investigation. Also, the construction of a new type of interferometer that has the potential to significantly increase the enclosed area and thus its sensitivity is in progress. Finally an idea to separate an electron beam fully into its two spin component using an electron interferometer is presented. We gratefully acknowledge funding by NSF Grant No. 0969506 and R. B. and S. M. acknowledge DOE-GAANN fellowships.

  6. Reflective small angle electron scattering to characterize nanostructures on opaque substrates

    NASA Astrophysics Data System (ADS)

    Friedman, Lawrence H.; Wu, Wen-Li; Fu, Wei-En; Chien, Yunsan

    2017-09-01

    Feature sizes in integrated circuits (ICs) are often at the scale of 10 nm and are ever shrinking. ICs appearing in today's computers and hand held devices are perhaps the most prominent examples. These smaller feature sizes demand equivalent advances in fast and accurate dimensional metrology for both development and manufacturing. Techniques in use and continuing to be developed include X-ray based techniques, optical scattering, and of course the electron and scanning probe microscopy techniques. Each of these techniques has their advantages and limitations. Here, the use of small angle electron beam scattering measurements in a reflection mode (RSAES) to characterize the dimensions and the shape of nanostructures on flat and opaque substrates is demonstrated using both experimental and theoretical evidence. In RSAES, focused electrons are scattered at angles smaller than 1 ° with the assistance of electron optics typically used in transmission electron microscopy. A proof-of-concept experiment is combined with rigorous electron reflection simulations to demonstrate the efficiency and accuracy of RSAES as a method of non-destructive measurement of shapes of features less than 10 nm in size on flat and opaque substrates.

  7. Reflective Small Angle Electron Scattering to Characterize Nanostructures on Opaque Substrates.

    PubMed

    Friedman, Lawrence H; Wu, Wen-Li; Fu, Wei-En; Chien, Yunsan

    2017-09-01

    Features sizes in integrated circuits (ICs) are often at the scale of 10 nm and are ever shrinking. ICs appearing in today's computers and hand held devices are perhaps the most prominent examples. These smaller feature sizes demand equivalent advances in fast and accurate dimensional metrology for both development and manufacturing. Techniques in use and continuing to be developed include X-ray based techniques, optical scattering and of course the electron and scanning probe microscopy techniques. Each of these techniques have their advantages and limitations. Here the use of small angle electron beam scattering measurements in a reflection mode (RSAES) to characterize the dimensions and the shape of nanostructures on flat and opaque substrates is demonstrated using both experimental and theoretical evidence. In RSAES, focused electrons are scattered at angles smaller than 1° with the assistance of electron optics typically used in transmission electron microscopy. A proof-of-concept experiment is combined with rigorous electron reflection simulations to demonstrate the efficiency and accuracy of RSAES as a method of non-destructive measurement of shapes of features less than 10 nm in size on flat and opaque substrates.

  8. More than Just a Pretty (Inter) Face: The Role of the Graphical User Interface in Engaging Elearners.

    ERIC Educational Resources Information Center

    Metros, Susan E.; Hedberg, John G.

    2002-01-01

    Examines the relationship between the graphical user interface (GUI) and the cognitive demands placed on the learner in eLearning (electronic learning) environments. Describes ways educators can design appropriate interfaces to facilitate meaningful interactions with educational content; and examines learner engagement and engagement theory using…

  9. Turning a dream into reality: the evolution of a seamless electronic health record.

    PubMed

    Dalander, G; Willner, S; Brasch, S

    1997-10-01

    Growing competition in the healthcare industry has created a strong-demand for improvement in all areas. Learn how integrated delivery systems have been created and effectively utilized in order to change how the business side of healthcare is conducted and how provider organizations measure and achieve success.

  10. Getting in Touch

    ERIC Educational Resources Information Center

    Dyrli, Kurt O.

    2008-01-01

    This article discusses the growing demand of using touchscreen interface. Consumers are now seeing touchscreens in a wide variety of electronics, not only in competitors to the iPhone from Sony, Samsung, Motorola, LG and T-Mobile, but also in desktop PCs, printers and copiers, televisions, and MP3 players. Teens, if they don't have a touch-enabled…

  11. Intelligent Performance Assessment of Students' Laboratory Work in a Virtual Electronic Laboratory Environment

    ERIC Educational Resources Information Center

    Achumba, I. E.; Azzi, D.; Dunn, V. L.; Chukwudebe, G. A.

    2013-01-01

    Laboratory work is critical in undergraduate engineering courses. It is used to integrate theory and practice. This demands that laboratory activities are synchronized with lectures to maximize their derivable learning outcomes, which are measurable through assessment. The typical high costs of the traditional engineering laboratory, which often…

  12. A Study of Trends in the Demand for Information Transfer. Final Report.

    ERIC Educational Resources Information Center

    Hough, R. W.; And Others

    The scope of the research reported here is summarized as follows: (1) consider items of information that could conceivably be transmitted electrically or electronically, (2) concentrate on domestic U.S. rather than international traffic, (3) concentrate on point-to-point service, (4) consider data collection and broadcasting services only as they…

  13. Developing a Web-Based Mechanism for Assessing Teacher Science Content Knowledge

    ERIC Educational Resources Information Center

    Byers, Al; Koba, Susan; Sherman, Greg; Scheppke, Joan; Bolus, Roger

    2011-01-01

    The National Science Teachers Association (NSTA) recently launched a comprehensive electronic professional development (e-PD) online portal, the NSTA Learning Center. This support site for educators currently includes over 6,000 e-PD resources and opportunities available on-demand, as well as various tools designed to help educators maximize the…

  14. Creating New Learning Communities: Towards Effective E-Learning Production.

    ERIC Educational Resources Information Center

    Russell, David; Calvey, David; Banks, Mark

    2003-01-01

    Case study research and a literature review suggest that formation of new learning communities is a strategy being used to meet demand for electronic learning products such as CD-ROMs and web-based learning tools. Companies, external experts, clients, and learners are the constituents of the learning community that must converge to create…

  15. Electronic Scientific Data & Literature Aggregation: A Review for Librarians

    ERIC Educational Resources Information Center

    Losoff, Barbara

    2009-01-01

    The advent of large-scale digital repositories, along with the need for sharing useful data world-wide, demands change to the current information structure. The merging of digital scientific data with scholarly literature has the potential to fulfill the Semantic Web design principles. This paper will identify factors leading to integration of…

  16. The Virtual Campus: Technology and Reform in Higher Education. ASHE-ERIC Higher Education Report, Volume 25, No. 5.

    ERIC Educational Resources Information Center

    Van Dusen, Gerald C.

    The "virtual campus" is a metaphor for the electronic teaching, learning, and research environment created by the convergence of several relatively new technologies including, but not restricted to, the Internet, World Wide Web, computer-mediated communication, video conferencing, multi-media, groupware, video-on-demand, desktop…

  17. Posttraumatic stress disorder, depression, and alcohol and tobacco use in public health workers after the 2004 Florida hurricanes.

    PubMed

    Fullerton, Carol S; McKibben, Jodi B A; Reissman, Dori B; Scharf, Ted; Kowalski-Trakofler, Kathleen M; Shultz, James M; Ursano, Robert J

    2013-02-01

    We examined the relationship of probable posttraumatic stress disorder (PTSD), probable depression, and increased alcohol and/or tobacco use to disaster exposure and work demand in Florida Department of Health workers after the 2004 hurricanes. Participants (N = 2249) completed electronic questionnaires assessing PTSD, depression, alcohol and tobacco use, hurricane exposure, and work demand. Total mental and behavioral health burden (probable PTSD, probable depression, increased alcohol and/or tobacco use) was 11%. More than 4% had probable PTSD, and 3.8% had probable depression. Among those with probable PTSD, 29.2% had increased alcohol use, and 50% had increased tobacco use. Among those with probable depression, 34% indicated increased alcohol use and 55.6% increased tobacco use. Workers with greater exposure were more likely to have probable PTSD and probable depression (ORs = 3.3 and 3.06, respectively). After adjusting for demographics and work demand, those with high exposure were more likely to have probable PTSD and probable depression (ORs = 3.21 and 3.13). Those with high exposure had increased alcohol and tobacco use (ORs = 3.01 and 3.40), and those with high work demand indicated increased alcohol and tobacco use (ORs = 1.98 and 2.10). High exposure and work demand predicted increased alcohol and tobacco use, after adjusting for demographics, work demand, and exposure. Work-related disaster mental and behavioral health burden indicate the need for additional mental health interventions in the public health disaster workforce.

  18. Posttraumatic Stress Disorder, Depression, and Alcohol and Tobacco Use in Public Health Workers After the 2004 Florida Hurricanes

    PubMed Central

    Fullerton, Carol S.; McKibben, Jodi B.A.; Reissman, Dori B.; Scharf, Ted; Kowalski-Trakofler, Kathleen M.; Shultz, James M.; Ursano, Robert J.

    2015-01-01

    Objective We examined the relationship of probable posttraumatic stress disorder (PTSD), probable depression, and increased alcohol and/or tobacco use to disaster exposure and work demand in Florida Department of Health workers after the 2004 hurricanes. Methods Participants (N = 2249) completed electronic questionnaires assessing PTSD, depression, alcohol and tobacco use, hurricane exposure, and work demand. Results Total mental and behavioral health burden (probable PTSD, probable depression, increased alcohol and/or tobacco use) was 11%. More than 4% had probable PTSD, and 3.8% had probable depression. Among those with probable PTSD, 29.2% had increased alcohol use, and 50% had increased tobacco use. Among those with probable depression, 34% indicated increased alcohol use and 55.6% increased tobacco use. Workers with greater exposure were more likely to have probable PTSD and probable depression (ORs = 3.3 and 3.06, respectively). After adjusting for demographics and work demand, those with high exposure were more likely to have probable PTSD and probable depression (ORs = 3.21 and 3.13). Those with high exposure had increased alcohol and tobacco use (ORs = 3.01 and 3.40), and those with high work demand indicated increased alcohol and tobacco use (ORs = 1.98 and 2.10). High exposure and work demand predicted increased alcohol and tobacco use, after adjusting for demographics, work demand, and exposure. Conclusions Work-related disaster mental and behavioral health burden indicate the need for additional mental health interventions in the public health disaster workforce. PMID:24618140

  19. Estimating the impact of the home appliances trade-in policy on WEEE management in China.

    PubMed

    Zhu, Shuguang; He, Wenzhi; Li, Guangming; Zhuang, Xuning; Huang, Juwen; Liang, Honggen; Han, Yuebin

    2012-11-01

    The ever-increasing amount of waste electric and electronic equipment (WEEE) has become a global problem. In view of the deleterious effects of WEEE on the environment and the valuable materials that can be reused in them, many countries have focused their attention on the management of WEEE and the recovery technologies of WEEE. The Chinese government has been active in creating a legislative and institutional framework to realize WEEE recycling. In June 2009, Chinese government launched home appliances and electronics trade-in implementation solution. This paper elaborates the home appliances trade-in policy and its significant impact on the WEEE management. The trade-in policy is not only conducive to expanding the consumption demand and promoting the balance of domestic and overseas demand, but also favorable to improving the energy efficiency and reducing environmental pollution. Under this policy, China has successfully established an effective WEEE recycling system, using the financial means and network design. Experiences gained from the trade-in policy have shown that management systems of WEEE need to be designed and implemented in a multi-stakeholder dialogue.

  20. A compact, low-loss, tunable phase shifter on defect mitigated dielectrics up to 40 GHz

    NASA Astrophysics Data System (ADS)

    Orloff, Nathan; Long, Christian; Lu, Xifeng; Nair, Hari; Dawley, Natalie; Schlom, Darrell; Booth, James

    With the emergence of the internet-of-things and increased connectivity of modern commerce, consumers have driven demand for wireless spectrum beyond current capacity and infrastructure capabilities. One way the telecommunications industry is addressing this problem is by pushing front-end electronics to higher frequencies, introducing carrier aggregation schemes, and developing spectrum-sharing techniques. Some of these solutions require frequency agile components that are vastly different from what is in today's marketplace. Perhaps the most basic and ubiquitous component in front-end electronics is the phase shifter. Phase shifters are particularly important for compact beam-forming antennas that may soon appear in commercial technology. Here, we demonstrate a compact, tunable phase shifter with very low insertion loss up to 40 GHz on a defect mitigated tunable dielectric. We demonstrate performance compared to barium-doped strontium titanate phase shifters. Such phase shifters could potentially meet the stringent size and performance characteristics demanded by telecommunications industry, readily facilitating massive multiple-input multiple-output antennas in the next-generation of mobile handsets.

  1. Analyses of odours from concentrated animal feeding operations: A review

    NASA Astrophysics Data System (ADS)

    Guffanti, P.; Pifferi, V.; Falciola, L.; Ferrante, V.

    2018-02-01

    Concentrated Animal Feeding Operations (CAFOs) are widely present all over the world due to the high population demand for food and products of animal origin. However, they have generated several environmental concerns, including odour nuisance, which affects people health and quality of life. Odours from livestock are a very complex mixtures of molecules and their analytical investigation is highly demanding. Many works have been published regarding the study of odours from CAFOs, using different techniques and technologies to face the issue. Thus, the aim of this review paper is to summarize all the ways to study odours from CAFOs, starting from the sampling methods and then treating in general the principles of Dynamic Olfactometry, Gas Chromatography coupled with Mass Spectrometry and Electronic Noses. Finally, a deep literature summary of Gas Chromatography coupled with Mass Spectrometry and Electronic Noses applied to odours coming from poultry, dairy and swine feeding operations is reported. This work aims to make some order in this field and it wants to help future researchers to deal with this environmental problem, constituting a state-of-the-art in this field.

  2. Improvement of a microbial fuel cell performance as a BOD sensor using respiratory inhibitors.

    PubMed

    Chang, In Seop; Moon, Hyunsoo; Jang, Jae Kyung; Kim, Byung Hong

    2005-03-15

    Studies were made to improve the performance of a microbial fuel cell (MFC) as a biochemical oxygen demand (BOD) sensor. The signal from MFCs decreased in the presence of electron acceptors of higher redox potential such as nitrate and oxygen. The addition of azide and cyanide did not change the signal in the absence of the electron acceptors. The respiratory inhibitors eliminated the inhibitory effects of the electron acceptors on the current generation from MFCs. Similar results were obtained using oligotrophic MFCs fed with an environmental sample that contained nitrate. The use of the respiratory inhibitors is therefore recommended for the accurate BOD measurement of environmental samples containing nitrate and/or oxygen with an MFC-type BOD sensor.

  3. Space shuttle main engine controller

    NASA Technical Reports Server (NTRS)

    Mattox, R. M.; White, J. B.

    1981-01-01

    A technical description of the space shuttle main engine controller, which provides engine checkout prior to launch, engine control and monitoring during launch, and engine safety and monitoring in orbit, is presented. Each of the major controller subassemblies, the central processing unit, the computer interface electronics, the input electronics, the output electronics, and the power supplies are described and discussed in detail along with engine and orbiter interfaces and operational requirements. The controller represents a unique application of digital concepts, techniques, and technology in monitoring, managing, and controlling a high performance rocket engine propulsion system. The operational requirements placed on the controller, the extremely harsh operating environment to which it is exposed, and the reliability demanded, result in the most complex and rugged digital system ever designed, fabricated, and flown.

  4. Mesoporous aluminium organophosphonates: a reusable chemsensor for the detection of explosives

    NASA Astrophysics Data System (ADS)

    Li, Dongdong; Yu, Xiang

    2016-07-01

    Rapid and sensitive detection of explosives is in high demand for homeland security and public safety. In this work, electron-rich of anthracene functionalized mesoporous aluminium organophosphonates (En-AlPs) were synthesized by a one-pot condensation process. The mesoporous structure and strong blue emission of En-AlPs were confirmed by the N2 adsorption-desorption isotherms, transmission electron microscopy images and fluorescence spectra. The materials En-AlPs can serve as sensitive chemosensors for various electron deficient nitroderivatives, with the quenching constant and the detection limit up to 1.5×106 M-1 and 0.3 ppm in water solution. More importantly, the materials can be recycled for many times by simply washed with ethanol, showing potential applications in explosives detection.

  5. 2D lateral heterostructures of group-III monochalcogenide: Potential photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Cheng, Kai; Guo, Yu; Han, Nannan; Jiang, Xue; Zhang, Junfeng; Ahuja, Rajeev; Su, Yan; Zhao, Jijun

    2018-04-01

    Solar photovoltaics provides a practical and sustainable solution to the increasing global energy demand. Using first-principles calculations, we investigate the energetics and electronic properties of two-dimensional lateral heterostructures by group-III monochalcogenides and explore their potential applications in photovoltaics. The band structures and formation energies from supercell calculations demonstrate that these heterostructures retain semiconducting behavior and might be synthesized in laboratory using the chemical vapor deposition technique. According to the computed band offsets, most of the heterojunctions belong to type II band alignment, which can prevent the recombination of electron-hole pairs. Besides, the electronic properties of these lateral heterostructures can be effectively tailored by the number of layers, leading to a high theoretical power conversion efficiency over 20%.

  6. Detection of low frequency external electronic identification devices using commercial panel readers.

    PubMed

    Stewart, S C; Rapnicki, P; Lewis, J R; Perala, M

    2007-09-01

    The ability of a commercially available panel reader system to read International Standards Organization-compliant electronic identification devices under commercial dairy conditions was examined. Full duplex (FDX-B) and half-duplex (HDX) low frequency radio-frequency identification external ear tags were utilized. The study involved 498 Holstein cows in the final 6 wk of gestation. There were 516 total electronic identification devices (n = 334 HDX and n = 182 FDX-B). Eighteen FDX-B were replaced with HDX during the study due to repeated detection failure. There were 6,679 HDX and 3,401 FDX-B device detection attempts. There were 220 (2.2%) unsuccessful and 9,860 (97.8%) successful identification detection attempts. There were 9 unsuccessful detection attempts for HDX (6,670/6,679 = 99.9% successful detection attempts) and 211 unsuccessful detection attempts for FDX-B (3,190/3,401 = 93.8% successful detection attempts). These results demonstrate that this panel system can achieve high detection rates of HDX devices and meet the needs of the most demanding management applications. The FDX-B detection rate was not sufficient for the most demanding applications, requiring a high degree of detection by panel readers. The lower FDX-B rate may not be inherent in the device technology itself, but could be due to other factors, including the particular panel reader utilized or the tuning of the panel reader.

  7. Recent advancements in the cobalt oxides, manganese oxides and their composite as an electrode material for supercapacitor: a review

    NASA Astrophysics Data System (ADS)

    Uke, Santosh J.; Akhare, Vijay P.; Bambole, Devidas R.; Bodade, Anjali B.; Chaudhari, Gajanan N.

    2017-08-01

    In this smart edge, there is an intense demand of portable electronic devices such as mobile phones, laptops, smart watches etc. That demands the use of such components which has light weight, flexible, cheap and environmental friendly. So that needs an evolution in technology. Supercapacitors are energy storage devices emerging as one of the promising energy storage devices in the future energy technology. Electrode material is the important part of supercapacitor. There is much new advancement in types of electrode materials as for supercapacitor. In this review, we focused on the recent advancements in the cobalt oxides, manganese oxides and their composites as an electrodes material for supercapacitor.

  8. Fiber To The Subscriber: Look At Narrowband Services First

    NASA Astrophysics Data System (ADS)

    Mangum, Karen L.

    1990-01-01

    Today, it's not easy to find a telecommunications publication that doesn't have a feature article on fiber to the home. Not only do these articles appear in telecommunications publications but in newspapers like in the Wall Street Journal and USA Today. What concerns me about these articles is the immediate emphasis on CATV and video on demand services. Fiber is indeed a broadband transmission medium. However, from BellSouths point of view, the video services are not necessary to the economic equation for placing fiber to the subscriber. Our objective is to place fiber in the network for POTS like services first and upgrade the electronics based on customer demand.

  9. The economic and social context of special populations.

    PubMed

    Ashford, N A

    1999-01-01

    Changes in both technology and international trade are altering the world economy and hence are affecting the demand and supply of labor and the nature of work and working conditions. New materials, faster and more powerful computers, electronic and mobile communications, alternative energy systems, miniaturization, robotics, and biotechnology pose new opportunities, problems, and challenges. The tremendous expansion in information-based technologies in both manufacturing and services has resulted in impressive increases in productivity and demand for new skills, but they also have brought about the displacement and de-skilling of some labor by capital, the lowering of wages, and the increase of contingent, part-time, and temporary work. Special populations, in particular, may be differentially impacted.

  10. The Need for Optical Means as an Alternative for Electronic Computing

    NASA Technical Reports Server (NTRS)

    Adbeldayem, Hossin; Frazier, Donald; Witherow, William; Paley, Steve; Penn, Benjamin; Bank, Curtis; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    An increasing demand for faster computers is rapidly growing to encounter the fast growing rate of Internet, space communication, and robotic industry. Unfortunately, the Very Large Scale Integration technology is approaching its fundamental limits beyond which the device will be unreliable. Optical interconnections and optical integrated circuits are strongly believed to provide the way out of the extreme limitations imposed on the growth of speed and complexity of nowadays computations by conventional electronics. This paper demonstrates two ultra-fast, all-optical logic gates and a high-density storage medium, which are essential components in building the future optical computer.

  11. Advanced nanomaterials

    NASA Astrophysics Data System (ADS)

    Titus, Elby; Ventura, João; Pedro Araújo, João; Campos Gil, João

    2017-12-01

    Nanomaterials provide a remarkably novel outlook to the design and fabrication of materials. The know-how of designing, modelling and fabrication of nanomaterials demands sophisticated experimental and analytical techniques. The major impact of nanomaterials will be in the fields of electronics, energy and medicine. Nanoelectronics hold the promise of improving the quality of life of electronic devices through superior performance, weight reduction and lower power consumption. New energy production systems based on hydrogen, solar and nuclear sources have also benefited immensely from nanomaterials. In modern medicine, nanomaterials research will have great impact on public health care due to better diagnostic methods and design of novel drugs.

  12. Evidence that pitch angle scattering is an important loss mechanism for energetic electrons in the inner radiation belt of Jupiter

    NASA Technical Reports Server (NTRS)

    Fillius, W.; Mcilwain, C.; Mogro-Campero, A.; Steinberg, G.

    1976-01-01

    Analysis of data from the Pioneer 10 flyby discloses that pitch angle scattering plays an important part in determining the distribution of energetic electrons in the inner magnetosphere of Jupiter. Angular distributions measured by a Cerenkov detector reveal that redistribution takes place in pitch angle. Additionally, the radial profile of phase space density along the equator demands simultaneous particle losses. The loss rates are too high to be accounted for by synchrotron radiation loss, but are reasonably attributed to pitch angle scattering into the planetary loss cone.

  13. Organic n-type materials for charge transport and charge storage applications.

    PubMed

    Stolar, Monika; Baumgartner, Thomas

    2013-06-21

    Conjugated materials have attracted much attention toward applications in organic electronics in recent years. These organic species offer many advantages as potential replacement for conventional materials (i.e., silicon and metals) in terms of cheap fabrication and environmentally benign devices. While p-type (electron-donating or hole-conducting) materials have been extensively reviewed and researched, their counterpart n-type (electron-accepting or electron-conducting) materials have seen much less popularity despite the greater need for improvement. In addition to developing efficient charge transport materials, it is equally important to provide a means of charge storage, where energy can be used on an on-demand basis. This perspective is focused on discussing a selection of representative n-type materials and the efforts toward improving their charge-transport efficiencies. Additionally, this perspective will also highlight recent organic materials for battery components and the efforts that have been made to improve their environmental appeal.

  14. Heuristic for learning common emitter amplification with bipolar transistors

    NASA Astrophysics Data System (ADS)

    Staffas, Kjell

    2017-11-01

    Mathematics in engineering education causes many thresholds in the courses because of the demand of abstract conceptualisation. Electronics depend heavily on more or less complex mathematics. Therefore the concepts of analogue electronics are hard to learn since a great deal of students struggle with the calculations and procedures needed. A survey was done focusing on students' struggle to pass a course in analogue electronics by introducing a top-down perspective and the revised taxonomy of Bloom. From a top-down perspective you can create learning environments from any spot in the taxonomy using a step-by-step approach of the verbs understand and apply. Three textbooks with a top-down perspective on analogue electronics are analysed on the concept of amplifying with a transistor circuit. The study claims issues when losing the top-down perspective to present concepts and procedures of the content to be learned.

  15. Heterogeneous Monolithic Integration of Single-Crystal Organic Materials.

    PubMed

    Park, Kyung Sun; Baek, Jangmi; Park, Yoonkyung; Lee, Lynn; Hyon, Jinho; Koo Lee, Yong-Eun; Shrestha, Nabeen K; Kang, Youngjong; Sung, Myung Mo

    2017-02-01

    Manufacturing high-performance organic electronic circuits requires the effective heterogeneous integration of different nanoscale organic materials with uniform morphology and high crystallinity in a desired arrangement. In particular, the development of high-performance organic electronic and optoelectronic devices relies on high-quality single crystals that show optimal intrinsic charge-transport properties and electrical performance. Moreover, the heterogeneous integration of organic materials on a single substrate in a monolithic way is highly demanded for the production of fundamental organic electronic components as well as complex integrated circuits. Many of the various methods that have been designed to pattern multiple heterogeneous organic materials on a substrate and the heterogeneous integration of organic single crystals with their crystal growth are described here. Critical issues that have been encountered in the development of high-performance organic integrated electronics are also addressed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Design reflowable digital book template

    NASA Astrophysics Data System (ADS)

    Prasetya, Didik Dwi; Widiyaningtyas, Triyanna; Arifin, M. Zainal; Wahyu Sakti G., I.

    2017-09-01

    Electronic books (e-books or digital books) increasingly in demand and continue to grow in the form of future books. One of the standard format electronic books that potential is EPUB (electronic publication) published by the International Digital Publishing Forum (IDPF). This digital book has major advantages are able to provide interactive and reflowable content, which are not found in another book format, such as PDF. Reflowable content allows the book can be accessed through a variety of reader device, like desktop and mobile with a fit and comfort view. However, because the generating process of an EPUB digital book is not as easy a PDF, so this format is less popular. Therefore, in order to help overcome the existing problems, this paper develops digital reflowable text book templates to support electronic learning, especially in Indonesia. This template can be used by anyone to produce a standard digital book quickly and easily without requiring additional specialized knowledge.

  17. Direct measurement of the pulse duration and frequency chirp of seeded XUV free electron laser pulses

    NASA Astrophysics Data System (ADS)

    Azima, Armin; Bödewadt, Jörn; Becker, Oliver; Düsterer, Stefan; Ekanayake, Nagitha; Ivanov, Rosen; Kazemi, Mehdi M.; Lamberto Lazzarino, Leslie; Lechner, Christoph; Maltezopoulos, Theophilos; Manschwetus, Bastian; Miltchev, Velizar; Müller, Jost; Plath, Tim; Przystawik, Andreas; Wieland, Marek; Assmann, Ralph; Hartl, Ingmar; Laarmann, Tim; Rossbach, Jörg; Wurth, Wilfried; Drescher, Markus

    2018-01-01

    We report on a direct time-domain measurement of the temporal properties of a seeded free-electron laser pulse in the extreme ultraviolet spectral range. Utilizing the oscillating electromagnetic field of terahertz radiation, a single-shot THz streak-camera was applied for measuring the duration as well as spectral phase of the generated intense XUV pulses. The experiment was conducted at FLASH, the free electron laser user facility at DESY in Hamburg, Germany. In contrast to indirect methods, this approach directly resolves and visualizes the frequency chirp of a seeded free-electron laser (FEL) pulse. The reported diagnostic capability is a prerequisite to tailor amplitude, phase and frequency distributions of FEL beams on demand. In particular, it opens up a new window of opportunities for advanced coherent spectroscopic studies making use of the high degree of temporal coherence expected from a seeded FEL pulse.

  18. Simple Method to Generate Terawatt-Attosecond X-Ray Free-Electron-Laser Pulses.

    PubMed

    Prat, Eduard; Reiche, Sven

    2015-06-19

    X-ray free-electron lasers (XFELs) are cutting-edge research tools that produce almost fully coherent radiation with high power and short-pulse length with applications in multiple science fields. There is a strong demand to achieve even shorter pulses and higher radiation powers than the ones obtained at state-of-the-art XFEL facilities. In this context we propose a novel method to generate terawatt-attosecond XFEL pulses, where an XFEL pulse is pushed through several short good-beam regions of the electron bunch. In addition to the elements of conventional XFEL facilities, the method uses only a multiple-slotted foil and small electron delays between undulator sections. Our scheme is thus simple, compact, and easy to implement both in already operating as well as future XFEL projects. We present numerical simulations that confirm the feasibility and validity of our proposal.

  19. Measuring the success of electronic medical record implementation using electronic and survey data.

    PubMed Central

    Keshavjee, K.; Troyan, S.; Holbrook, A. M.; VanderMolen, D.

    2001-01-01

    Computerization of physician practices is increasing. Stakeholders are demanding demonstrated value for their Electronic Medical Record (EMR) implementations. We developed survey tools to measure medical office processes, including administrative and physician tasks pre- and post-EMR implementation. We included variables that were expected to improve with EMR implementation and those that were not expected to improve, as controls. We measured the same processes pre-EMR, at six months and 18 months post-EMR. Time required for most administrative tasks decreased within six months of EMR implementation. Staff time spent on charting increased with time, in keeping with our anecdotal observations that nurses were given more responsibility for charting in many offices. Physician time to chart increased initially by 50%, but went down to original levels by 18 months. However, this may be due to the drop-out of those physicians who had a difficult time charting electronically. PMID:11825201

  20. Power SEMICONDUCTORS—STATE of Art and Future Trends

    NASA Astrophysics Data System (ADS)

    Benda, Vitezslav

    2011-06-01

    The importance of effective energy conversion control, including power generation from renewable and environmentally clean energy sources, increases due to rising energy demand. Power electronic systems for controlling and converting electrical energy have become the workhorse of modern society in many applications, both in industry and at home. Power electronics plays a very important role in traction and can be considered as brawns of robotics and automated manufacturing systems. Power semiconductor devices are the key electronic components used in power electronic systems. Advances in power semiconductor technology have improved the efficiency, size, weight and cost of power electronic systems. At present, IGCTs, IGBTs, and MOSFETs represent modern switching devices. Power integrated circuits (PIC) have been developed for the use of power converters for portable, automotive and aerospace applications. For advanced applications, new materials (SiC and GaN) have been introduced. This paper reviews the state of these devices and elaborates on their potentials in terms of higher voltages, higher power density, and better switching performance.

  1. Nurses' perceptions of the impact of electronic health records on work and patient outcomes.

    PubMed

    Kossman, Susan P; Scheidenhelm, Sandra L

    2008-01-01

    This study addresses community hospital nurses' use of electronic health records and views of the impact of such records on job performance and patient outcomes. Questionnaire, interview, and observation data from 46 nurses in medical-surgical and intensive care units at two community hospitals were analyzed. Nurses preferred electronic health records to paper charts and were comfortable with technology. They reported use of electronic health records enhanced nursing work through increased information access, improved organization and efficiency, and helpful alert screens. They thought use of the records hindered nursing work through impaired critical thinking, decreased interdisciplinary communication, and a high demand on work time (73% reported spending at least half their shift using the records). They thought use of electronic health records enabled them to provide safer care but decreased the quality of care. Administrative implications include involving bedside nurses in system choice, streamlining processes, developing guidelines for consistent documentation quality and location, increasing system speed, choosing hardware that encourages bedside use, and improving system information technology support.

  2. Extremely stretchable and conductive water-repellent coatings for low-cost ultra-flexible electronics

    PubMed Central

    Mates, Joseph E.; Bayer, Ilker S.; Palumbo, John M.; Carroll, Patrick J.; Megaridis, Constantine M.

    2015-01-01

    Rapid advances in modern electronics place ever-accelerating demands on innovation towards more robust and versatile functional components. In the flexible electronics domain, novel material solutions often involve creative uses of common materials to reduce cost, while maintaining uncompromised performance. Here we combine a commercially available paraffin wax–polyolefin thermoplastic blend (elastomer matrix binder) with bulk-produced carbon nanofibres (charge percolation network for electron transport, and for imparting nanoscale roughness) to fabricate adherent thin-film composite electrodes. The simple wet-based process produces composite films capable of sustained ultra-high strain (500%) with resilient electrical performance (resistances of the order of 101–102 Ω sq−1). The composites are also designed to be superhydrophobic for long-term corrosion protection, even maintaining extreme liquid repellency at severe strain. Comprised of inexpensive common materials applied in a single step, the present scalable approach eliminates manufacturing obstacles for commercially viable wearable electronics, flexible power storage devices and corrosion-resistant circuits. PMID:26593742

  3. A small electron donor in cobalt complex electrolyte significantly improves efficiency in dye-sensitized solar cells

    PubMed Central

    Hao, Yan; Yang, Wenxing; Zhang, Lei; Jiang, Roger; Mijangos, Edgar; Saygili, Yasemin; Hammarström, Leif; Hagfeldt, Anders; Boschloo, Gerrit

    2016-01-01

    Photoelectrochemical approach to solar energy conversion demands a kinetic optimization of various light-induced electron transfer processes. Of great importance are the redox mediator systems accomplishing the electron transfer processes at the semiconductor/electrolyte interface, therefore affecting profoundly the performance of various photoelectrochemical cells. Here, we develop a strategy—by addition of a small organic electron donor, tris(4-methoxyphenyl)amine, into state-of-art cobalt tris(bipyridine) redox electrolyte—to significantly improve the efficiency of dye-sensitized solar cells. The developed solar cells exhibit efficiency of 11.7 and 10.5%, at 0.46 and one-sun illumination, respectively, corresponding to a 26% efficiency improvement compared with the standard electrolyte. Preliminary stability tests showed the solar cell retained 90% of its initial efficiency after 250 h continuous one-sun light soaking. Detailed mechanistic studies reveal the crucial role of the electron transfer cascade processes within the new redox system. PMID:28000672

  4. Biocompatible and totally disintegrable semiconducting polymer for ultrathin and ultralightweight transient electronics

    PubMed Central

    Lei, Ting; Guan, Ming; Liu, Jia; Lin, Hung-Cheng; Pfattner, Raphael; McGuire, Allister F.; Huang, Tsung-Ching; Shao, Leilai; Cheng, Kwang-Ting; Tok, Jeffrey B.-H.; Bao, Zhenan

    2017-01-01

    Increasing performance demands and shorter use lifetimes of consumer electronics have resulted in the rapid growth of electronic waste. Currently, consumer electronics are typically made with nondecomposable, nonbiocompatible, and sometimes even toxic materials, leading to serious ecological challenges worldwide. Here, we report an example of totally disintegrable and biocompatible semiconducting polymers for thin-film transistors. The polymer consists of reversible imine bonds and building blocks that can be easily decomposed under mild acidic conditions. In addition, an ultrathin (800-nm) biodegradable cellulose substrate with high chemical and thermal stability is developed. Coupled with iron electrodes, we have successfully fabricated fully disintegrable and biocompatible polymer transistors. Furthermore, disintegrable and biocompatible pseudo-complementary metal–oxide–semiconductor (CMOS) flexible circuits are demonstrated. These flexible circuits are ultrathin (<1 μm) and ultralightweight (∼2 g/m2) with low operating voltage (4 V), yielding potential applications of these disintegrable semiconducting polymers in low-cost, biocompatible, and ultralightweight transient electronics. PMID:28461459

  5. Biocompatible and totally disintegrable semiconducting polymer for ultrathin and ultralightweight transient electronics.

    PubMed

    Lei, Ting; Guan, Ming; Liu, Jia; Lin, Hung-Cheng; Pfattner, Raphael; Shaw, Leo; McGuire, Allister F; Huang, Tsung-Ching; Shao, Leilai; Cheng, Kwang-Ting; Tok, Jeffrey B-H; Bao, Zhenan

    2017-05-16

    Increasing performance demands and shorter use lifetimes of consumer electronics have resulted in the rapid growth of electronic waste. Currently, consumer electronics are typically made with nondecomposable, nonbiocompatible, and sometimes even toxic materials, leading to serious ecological challenges worldwide. Here, we report an example of totally disintegrable and biocompatible semiconducting polymers for thin-film transistors. The polymer consists of reversible imine bonds and building blocks that can be easily decomposed under mild acidic conditions. In addition, an ultrathin (800-nm) biodegradable cellulose substrate with high chemical and thermal stability is developed. Coupled with iron electrodes, we have successfully fabricated fully disintegrable and biocompatible polymer transistors. Furthermore, disintegrable and biocompatible pseudo-complementary metal-oxide-semiconductor (CMOS) flexible circuits are demonstrated. These flexible circuits are ultrathin (<1 μm) and ultralightweight (∼2 g/m 2 ) with low operating voltage (4 V), yielding potential applications of these disintegrable semiconducting polymers in low-cost, biocompatible, and ultralightweight transient electronics.

  6. Effectiveness of demand generation interventions on use of modern contraceptives in low- and middle-income countries.

    PubMed

    Belaid, L; Dumont, A; Chaillet, N; Zertal, A; De Brouwere, V; Hounton, S; Ridde, V

    2016-10-01

    To synthesise evidence on the implementation, costs and cost-effectiveness of demand generation interventions and their effectiveness in improving uptake of modern contraception methods. A Cochrane systematic review was conducted. Searches were performed in electronic databases (MEDLINE, EMBASE) and the grey literature. Randomised controlled trials, cluster randomised trials and quasi-experimental studies, including controlled before-after studies (CBAs) and cost and cost-effectiveness studies that aimed to assess demand interventions (including community- and facility-based interventions, financial mechanisms and mass media campaigns) in low- and middle-income countries were considered. Meta-analyses and narrative synthesis were conducted. In total, 20 papers meeting the inclusion criteria were included in this review. Of those, 13 were used for meta-analysis. Few data were available on implementation and on the influence of context on demand interventions. Involving family members during counselling, providing education activities and increasing exposure to those activities could enhance the success of demand interventions. Demand generation interventions were positively associated with increases in current use (pooled OR 1.57; 95% CI: 1.46-1.69, P < 0.01). Financial mechanism interventions (vouchers) appeared effective to increase use of modern contraceptive methods (pooled OR 2.16; 95% CI: 1.91-2.45, P < 0.01; I 2 = 0%). Demand interventions improved knowledge (pooled OR 1.02; 95% CI 0.63-1.64, P = 0.93) and attitudes towards family planning and improved discussion with partners/husbands around modern contraceptive methods. However, given the limited number of studies included in each category of demand generation interventions, the dates of publication of the studies and their low quality, caution is advised in considering the results. Very limited evidence was available on costs; studies including data on costs were old and inconsistent. Demand generation interventions contribute to increases in modern contraceptive methods use. However, more studies with robust designs are needed to identify the most effective demand generation intervention to increase uptake of modern contraceptive methods. More evidence is also needed about implementation, costs and cost-effectiveness to inform decisions on sustainability and scaling-up. © 2016 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

  7. New Bottles for Old Wine? California State University Initiates an Electronic Core Journals Collection.

    ERIC Educational Resources Information Center

    Healy, Leigh Watson

    1999-01-01

    The Journal Access Core Collection (JACC) initiative of the California State University (CSU) enables libraries to address the demand for print journals collections in a cooperative acquisitions project by offering their most heavily used journals to all CSU users on the Web. Implementation of the JACC, its key requirements and future…

  8. Organization Made Easy! Tools for Today's Teachers

    ERIC Educational Resources Information Center

    Buck, Frank

    2010-01-01

    Meet the ever-growing organizational demands of today's changing world with the variety of tools, digital and otherwise, available to you as a teacher. In this book, organization guru Frank Buck shows you how to take expert advantage of the specific electronic and paper-based resources that will help you manage your time and stay on course as a…

  9. 76 FR 66211 - Enhancement of Electricity Market Surveillance and Analysis Through Ongoing Electronic Delivery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-26

    ... indicating the price at which they are willing to supply various quantities of energy. Load- serving entities submit demand bids indicating the price at which they are willing to buy various quantities of energy... resources can affect the market price and whether the offers should be mitigated. If an energy supply offer...

  10. An Examination of the Impacts of Stress and Coping/Wellness Strategies of Information Technology Workers in the Higher Education Field

    ERIC Educational Resources Information Center

    Mroczko, Jennifer R.

    2017-01-01

    The Information Technology (IT) field infiltrates much of our daily lives. It has changed the way we conduct business, communicate, research, and learn. Individuals demand the latest and greatest - faster and better electronic devices, systems, and Internet. Businesses and organizations constantly require upgrades, improvements, or replacements to…

  11. E-Competent Australia: Report on the Impact of E-Commerce on the National Training Framework.

    ERIC Educational Resources Information Center

    Mitchell, John

    The impact of electronic commerce (e-commerce) on Australia's National Training Framework (NTF) was studied for the purpose of forecasting future demand for training in areas related to e-commerce and identifying appropriate responses by the NTF committee. The following were among the study's main data collection activities: reviews of the…

  12. Competencies Required for Healthcare Information Technology to Be an Effective Strategic Business Change Partner

    ERIC Educational Resources Information Center

    Davalos, Eugenia

    2013-01-01

    One of the core strategies to transform the United States national healthcare system is the implementation of key technologies such as the electronic patient medical record. Such key technologies improve patient care and help the organization gain competitive advantage. With a high demand for strategic and operational change, healthcare providers…

  13. The Device versus the Book

    ERIC Educational Resources Information Center

    Demski, Jennifer

    2010-01-01

    Electronic readers may be ushering in a watershed moment in personal reading, with the Amazon Kindle, Sony Reader, and Barnes & Noble Nook duking it out for market dominance (and with the iPad warming up in the wings). But how do these contenders fare in the academic marketplace? When it comes to meeting the demands of academic reading,…

  14. POLLUTION REDUCTION AND RESOURCES SAVING THROUGH THE USE OF WASTE DERIVED GAS FOR FUELING A HIGH TEMPERATURE FUEL CELL

    EPA Science Inventory

    In the most recent years, the world energy demand rose quickly. Production of millions of new cars every year, development of electronic devices that use hundreds of watts each, replacing human labor with machines in the factories and many others, lead world oil production close...

  15. Information Seeking about the Military by Young Men: Findings from the 1989 Youth Attitude Tracking Study II

    DTIC Science & Technology

    1991-02-01

    its use of high technologies and its high-caliber tram- ing in a very demanding electronic environment. The Navy’s advertising strategy is similar to...element of their advertising strategy is the use of direct mail campaigns. The content of broadcast and direct mail advertising messages often

  16. "Aska" Do's, Don'ts, and How-To's: Lessons Learned in a Library.

    ERIC Educational Resources Information Center

    Tomaiuolo, Nicholas G.; Packer, Joan G.

    2000-01-01

    Examines the growing demand for e-mail reference (Aska) service and how librarians can best manage an electronic help desk. Discusses problems of minimal information and anonymous patrons, followed by views on restricting/not restricting access to the service. Suggests ways to try to screen requests and specify a clientele. Notes the importance of…

  17. E-Portfolios as a Pedagogical Device in Primary Teacher Education: The AUT University Experience

    ERIC Educational Resources Information Center

    Maher, Marguerite; Gerbic, Philippa

    2009-01-01

    Portfolios have a long tradition in teacher education and now these are available in electronic form. At the same time, there are increasing demands for primary teachers to be technologically capable and confident in classrooms. When teacher educators wish to respond through the introduction of new technologies such as e-portfolios, there are…

  18. Making the Case for Formalizing the Lingo and Acronyms of Virtual Environments Communication to Meet Global Demands

    ERIC Educational Resources Information Center

    Malala, John N.

    2006-01-01

    There is overwhelming research and anecdotal evidence suggesting that traditional letter writing has significantly dwindled due to the increase use of email, online chats, telephone, and other electronic communication devices. People who became mainly dependent on internet relay chats in the late 1990s found themselves developing a new phraseology…

  19. Expanding the Media Mix in Statistics Education through Platform-Independent and Interactive Learning Objects

    ERIC Educational Resources Information Center

    Mittag, Hans-Joachim

    2015-01-01

    The ubiquity of mobile devices demands the exploitation of their potentials in distance and face-to-face teaching, as well for complementing textbooks in printed or electronic format. There is a strong need to develop innovative resources that open up new dimensions of learning and teaching through interactive and platform-independent content.…

  20. A Fit-Gap Analysis of E-Business Curricula and Job Demand in Taiwan and the US

    ERIC Educational Resources Information Center

    Li, Eldon Y.; Yen, H. J. Rebecca; Cheng, C. Y. John

    2008-01-01

    During the past decade, many enterprises have been re-directing their resources into critical business areas to keep up with economic and market changes. They have adopted electronic business (EB) systems, such as supply chain management, enterprise resource planning (ERP), and enterprise application integration (EAI), to ensure seamless…

  1. Scalable Sub-micron Patterning of Organic Materials Toward High Density Soft Electronics.

    PubMed

    Kim, Jaekyun; Kim, Myung-Gil; Kim, Jaehyun; Jo, Sangho; Kang, Jingu; Jo, Jeong-Wan; Lee, Woobin; Hwang, Chahwan; Moon, Juhyuk; Yang, Lin; Kim, Yun-Hi; Noh, Yong-Young; Jaung, Jae Yun; Kim, Yong-Hoon; Park, Sung Kyu

    2015-09-28

    The success of silicon based high density integrated circuits ignited explosive expansion of microelectronics. Although the inorganic semiconductors have shown superior carrier mobilities for conventional high speed switching devices, the emergence of unconventional applications, such as flexible electronics, highly sensitive photosensors, large area sensor array, and tailored optoelectronics, brought intensive research on next generation electronic materials. The rationally designed multifunctional soft electronic materials, organic and carbon-based semiconductors, are demonstrated with low-cost solution process, exceptional mechanical stability, and on-demand optoelectronic properties. Unfortunately, the industrial implementation of the soft electronic materials has been hindered due to lack of scalable fine-patterning methods. In this report, we demonstrated facile general route for high throughput sub-micron patterning of soft materials, using spatially selective deep-ultraviolet irradiation. For organic and carbon-based materials, the highly energetic photons (e.g. deep-ultraviolet rays) enable direct photo-conversion from conducting/semiconducting to insulating state through molecular dissociation and disordering with spatial resolution down to a sub-μm-scale. The successful demonstration of organic semiconductor circuitry promise our result proliferate industrial adoption of soft materials for next generation electronics.

  2. Programmable Hydrogel Ionic Circuits for Biologically Matched Electronic Interfaces.

    PubMed

    Zhao, Siwei; Tseng, Peter; Grasman, Jonathan; Wang, Yu; Li, Wenyi; Napier, Bradley; Yavuz, Burcin; Chen, Ying; Howell, Laurel; Rincon, Javier; Omenetto, Fiorenzo G; Kaplan, David L

    2018-06-01

    The increased need for wearable and implantable medical devices has driven the demand for electronics that interface with living systems. Current bioelectronic systems have not fully resolved mismatches between engineered circuits and biological systems, including the resulting pain and damage to biological tissues. Here, salt/poly(ethylene glycol) (PEG) aqueous two-phase systems are utilized to generate programmable hydrogel ionic circuits. High-conductivity salt-solution patterns are stably encapsulated within PEG hydrogel matrices using salt/PEG phase separation, which route ionic current with high resolution and enable localized delivery of electrical stimulation. This strategy allows designer electronics that match biological systems, including transparency, stretchability, complete aqueous-based connective interface, distribution of ionic electrical signals between engineered and biological systems, and avoidance of tissue damage from electrical stimulation. The potential of such systems is demonstrated by generating light-emitting diode (LED)-based displays, skin-mounted electronics, and stimulators that deliver localized current to in vitro neuron cultures and muscles in vivo with reduced adverse effects. Such electronic platforms may form the basis of future biointegrated electronic systems. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Scalable Sub-micron Patterning of Organic Materials Toward High Density Soft Electronics

    NASA Astrophysics Data System (ADS)

    Kim, Jaekyun; Kim, Myung-Gil; Kim, Jaehyun; Jo, Sangho; Kang, Jingu; Jo, Jeong-Wan; Lee, Woobin; Hwang, Chahwan; Moon, Juhyuk; Yang, Lin; Kim, Yun-Hi; Noh, Yong-Young; Yun Jaung, Jae; Kim, Yong-Hoon; Kyu Park, Sung

    2015-09-01

    The success of silicon based high density integrated circuits ignited explosive expansion of microelectronics. Although the inorganic semiconductors have shown superior carrier mobilities for conventional high speed switching devices, the emergence of unconventional applications, such as flexible electronics, highly sensitive photosensors, large area sensor array, and tailored optoelectronics, brought intensive research on next generation electronic materials. The rationally designed multifunctional soft electronic materials, organic and carbon-based semiconductors, are demonstrated with low-cost solution process, exceptional mechanical stability, and on-demand optoelectronic properties. Unfortunately, the industrial implementation of the soft electronic materials has been hindered due to lack of scalable fine-patterning methods. In this report, we demonstrated facile general route for high throughput sub-micron patterning of soft materials, using spatially selective deep-ultraviolet irradiation. For organic and carbon-based materials, the highly energetic photons (e.g. deep-ultraviolet rays) enable direct photo-conversion from conducting/semiconducting to insulating state through molecular dissociation and disordering with spatial resolution down to a sub-μm-scale. The successful demonstration of organic semiconductor circuitry promise our result proliferate industrial adoption of soft materials for next generation electronics.

  4. A correlative optical microscopy and scanning electron microscopy approach to locating nanoparticles in brain tumors.

    PubMed

    Kempen, Paul J; Kircher, Moritz F; de la Zerda, Adam; Zavaleta, Cristina L; Jokerst, Jesse V; Mellinghoff, Ingo K; Gambhir, Sanjiv S; Sinclair, Robert

    2015-01-01

    The growing use of nanoparticles in biomedical applications, including cancer diagnosis and treatment, demands the capability to exactly locate them within complex biological systems. In this work a correlative optical and scanning electron microscopy technique was developed to locate and observe multi-modal gold core nanoparticle accumulation in brain tumor models. Entire brain sections from mice containing orthotopic brain tumors injected intravenously with nanoparticles were imaged using both optical microscopy to identify the brain tumor, and scanning electron microscopy to identify the individual nanoparticles. Gold-based nanoparticles were readily identified in the scanning electron microscope using backscattered electron imaging as bright spots against a darker background. This information was then correlated to determine the exact location of the nanoparticles within the brain tissue. The nanoparticles were located only in areas that contained tumor cells, and not in the surrounding healthy brain tissue. This correlative technique provides a powerful method to relate the macro- and micro-scale features visible in light microscopy with the nanoscale features resolvable in scanning electron microscopy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Probing Chemical Bonding and Electronic Structures in ThO- by Anion Photoelectron Imaging and Theoretical Calculations.

    PubMed

    Li, Yanli; Zou, Jinghan; Xiong, Xiao-Gen; Su, Jing; Xie, Hua; Fei, Zejie; Tang, Zichao; Liu, Hongtao

    2017-03-16

    Because of renewed research on thorium-based molten salt reactors, there is growing demand and interest in enhancing the knowledge of thorium chemistry both experimentally and theoretically. Compared with uranium, thorium has few chemical studies reported up to the present. Here we report the vibrationally resolved photoelectron imaging of the thorium monoxide anion. The electron affinity of ThO is first reported to be 0.707 ± 0.020 eV. Vibrational frequencies of the ThO molecule and its anion are determined from Franck-Condon simulation. Spectroscopic evidence is obtained for the two-electron transition in ThO - , indicating the strong electron correlation among the (7s σ ) 2 (6d δ ) 1 electrons in ThO - and the (7s σ ) 2 electrons in ThO. These findings are explained by using quantum-chemical calculations including spin-orbit coupling, and the chemical bonding of gaseous ThO molecules is analyzed. The present work will enrich our understanding of bonding capacities with the 6d valence shell.

  6. Room Temperature Sulfur Battery Cathode Design and Processing Techniques

    NASA Astrophysics Data System (ADS)

    Carter, Rachel

    As the population grows and energy demand increases, climate change threatens causing energy storage research to focus on fulfilling the requirements of two major energy sectors with next generation batteries: (1) portable energy and (2) stationary storage.1 Where portable energy can decrease transportation-related harmful emissions and enable advanced next-generation technologies,1 and stationary storage can facilitate widespread deployment of renewable energy sources, alleviating the demand on fossil fuels and lowering emissions. Portable energy can enable zero-emission transportation and can deploy portable power in advanced electronics across fields including medical and defense. Currently fully battery powered cars are limited in driving distance, which is dictated by the energy density and weight of the state-of-the-art Li-ion battery, and similarly advancement of portable electronics is significantly hindered by heavy batteries with short charge lives. In attempt to enable advanced portable energy, significant research is aiming to improve the conventional Li-ion batteries and explore beyond Li-ion battery chemistries with the primary goal of demonstrating higher energy density to enable lighter weight cells with longer battery life. Further, with the inherent intermittency challenges of our most prominent renewable energy sources, wind and solar, discovery of batteries capable of cost effectively and reliably balancing the generation of the renewable energy sources with the real-time energy demand is required for grid scale viability. Stationary storage will provide load leveling to renewable resources by storing excess energy at peak generation and delivering stored excess during periods of lower generation. This application demands highly abundant, low-cost active materials and long-term cycle stability, since infrastructure costs (combined with the renewable) must compete with burning natural gas. Development of a battery with these characteristics will require exploration of chemistries beyond the Li-ion battery for a system consisting of low cost active materials and promising device performance. (Abstract shortened by ProQuest.).

  7. Decomposed multidimensional control grid interpolation for common consumer electronic image processing applications

    NASA Astrophysics Data System (ADS)

    Zwart, Christine M.; Venkatesan, Ragav; Frakes, David H.

    2012-10-01

    Interpolation is an essential and broadly employed function of signal processing. Accordingly, considerable development has focused on advancing interpolation algorithms toward optimal accuracy. Such development has motivated a clear shift in the state-of-the art from classical interpolation to more intelligent and resourceful approaches, registration-based interpolation for example. As a natural result, many of the most accurate current algorithms are highly complex, specific, and computationally demanding. However, the diverse hardware destinations for interpolation algorithms present unique constraints that often preclude use of the most accurate available options. For example, while computationally demanding interpolators may be suitable for highly equipped image processing platforms (e.g., computer workstations and clusters), only more efficient interpolators may be practical for less well equipped platforms (e.g., smartphones and tablet computers). The latter examples of consumer electronics present a design tradeoff in this regard: high accuracy interpolation benefits the consumer experience but computing capabilities are limited. It follows that interpolators with favorable combinations of accuracy and efficiency are of great practical value to the consumer electronics industry. We address multidimensional interpolation-based image processing problems that are common to consumer electronic devices through a decomposition approach. The multidimensional problems are first broken down into multiple, independent, one-dimensional (1-D) interpolation steps that are then executed with a newly modified registration-based one-dimensional control grid interpolator. The proposed approach, decomposed multidimensional control grid interpolation (DMCGI), combines the accuracy of registration-based interpolation with the simplicity, flexibility, and computational efficiency of a 1-D interpolation framework. Results demonstrate that DMCGI provides improved interpolation accuracy (and other benefits) in image resizing, color sample demosaicing, and video deinterlacing applications, at a computational cost that is manageable or reduced in comparison to popular alternatives.

  8. High pressure generation by hot electrons driven ablation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Piriz, A. R.; Piriz, S. A.; Tahir, N. A.

    2013-11-15

    A previous model [Piriz et al. Phys. Plasmas 19, 122705 (2012)] for the ablation driven by the hot electrons generated in collisionless laser-plasma interactions in the framework of shock ignition is revisited. The impact of recent results indicating that for a laser wavelength λ = 0.35 μm the hot electron temperature θ{sub H} would be independent of the laser intensity I, on the resulting ablation pressure is considered. In comparison with the case when the scaling law θ{sub H}∼(Iλ{sup 2}){sup 1/3} is assumed, the generation of the high pressures needed for driving the ignitor shock may be more demanding. Intensitiesmore » above 10{sup 17} W/cm{sup 2} would be required for θ{sub H}=25−30 keV.« less

  9. An introduction to electronic learning and its use to address challenges in surgical training.

    PubMed

    Baran, Szczepan W; Johnson, Elizabeth J; Kehler, James

    2009-06-01

    The animal research community faces a shortage of surgical training opportunities along with an increasing demand for expertise in surgical techniques. One possible means of overcoming this challenge is the use of computer-based or electronic learning (e-learning) to disseminate material to a broad range of animal users. E-learning platforms can take many different forms, ranging from simple text documents that are posted online to complex virtual courses that incorporate dynamic video or audio content and in which students and instructors can interact in real time. The authors present an overview of e-learning and discuss its potential benefits as a supplement to hands-on rodent surgical training. They also discuss a few basic considerations in developing and implementing electronic courses.

  10. Development of electron beam ion source for nanoprocess using highly charged ions

    NASA Astrophysics Data System (ADS)

    Sakurai, Makoto; Nakajima, Fumiharu; Fukumoto, Takunori; Nakamura, Nobuyuki; Ohtani, Shunsuke; Mashiko, Shinro; Sakaue, Hiroyuki

    2005-07-01

    Highly charged ion is useful to produce nanostructure on various materials, and is key tool to realize single ion implantation technique. On such demands for the application to nanotechnology, we have designed an electron bean ion source. The design stresses on the volume of drift tubes where highly charged ions are confined and the efficiency of ion extraction from the drift tube through collector electrode in order to obtain intense ion beam as much as possible. The ion source uses a discrete superconducting magnet cooled by a closed-cycle refrigerator in order to reduce the running costs and to simplify the operating procedures. The electrodes of electron gun, drift tubes, and collector are enclosed in ultrahigh vacuum tube that is inserted into the bore of the magnet system.

  11. Laser-driven injector of electrons for IOTA

    NASA Astrophysics Data System (ADS)

    Romanov, Aleksandr

    2017-03-01

    Fermilab is developing the Integrable Optics Test Accelerator (IOTA) ring for experiments on nonlinear integrable optics. The machine will operate with either electron beams of 150 MeV or proton beams of 2.5 MeV energies, respectively. The stability of integrable optics depends critically on the precision of the magnetic lattice, which demands the use of beam-based lattice measurements for optics correction. In the proton mode, the low-energy proton beam does not represent a good probe for this application; hence we consider the use of a low-intensity reverse-injected electron beam of matched momentum (70 MeV). Such an injector could be implemented with the use of laser-driven acceleration techniques. This report presents the consideration for a laser-plasma injector for IOTA and discusses the requirements determined by the ring design.

  12. Computers for Manned Space Applications Base on Commercial Off-the-Shelf Components

    NASA Astrophysics Data System (ADS)

    Vogel, T.; Gronowski, M.

    2009-05-01

    Similar to the consumer markets there has been an ever increasing demand in processing power, signal processing capabilities and memory space also for computers used for science data processing in space. An important driver of this development have been the payload developers for the International Space Station, requesting high-speed data acquisition and fast control loops in increasingly complex systems. Current experiments now even perform video processing and compression with their payload controllers. Nowadays the requirements for a space qualified computer are often far beyond the capabilities of, for example, the classic SPARC architecture that is found in ERC32 or LEON CPUs. An increase in performance usually demands costly and power consuming application specific solutions. Continuous developments over the last few years have now led to an alternative approach that is based on complete electronics modules manufactured for commercial and industrial customers. Computer modules used in industrial environments with a high demand for reliability under harsh environmental conditions like chemical reactors, electrical power plants or on manufacturing lines are entered into a selection procedure. Promising candidates then undergo a detailed characterisation process developed by Astrium Space Transportation. After thorough analysis and some modifications, these modules can replace fully qualified custom built electronics in specific, although not safety critical applications in manned space. This paper focuses on the benefits of COTS1 based electronics modules and the necessary analyses and modifications for their utilisation in manned space applications on the ISS. Some considerations regarding overall systems architecture will also be included. Furthermore this paper will also pinpoint issues that render such modules unsuitable for specific tasks, and justify the reasons. Finally, the conclusion of this paper will advocate the implementation of COTS based electronics for a range of applications within specifically adapted systems. The findings in this paper are extrapolated from two reference computer systems, both having been launched in 2008. One of those was a LEON-2 based computer installed onboard the Columbus Orbital Facility while the other system consisted mainly of a commercial Power-PC module that was modified for a launch mounted on the ICC pallet in the Space Shuttle's cargo bay. Both systems are currently upgraded and extended for future applications.

  13. Molecular-Scale Electronics: From Concept to Function.

    PubMed

    Xiang, Dong; Wang, Xiaolong; Jia, Chuancheng; Lee, Takhee; Guo, Xuefeng

    2016-04-13

    Creating functional electrical circuits using individual or ensemble molecules, often termed as "molecular-scale electronics", not only meets the increasing technical demands of the miniaturization of traditional Si-based electronic devices, but also provides an ideal window of exploring the intrinsic properties of materials at the molecular level. This Review covers the major advances with the most general applicability and emphasizes new insights into the development of efficient platform methodologies for building reliable molecular electronic devices with desired functionalities through the combination of programmed bottom-up self-assembly and sophisticated top-down device fabrication. First, we summarize a number of different approaches of forming molecular-scale junctions and discuss various experimental techniques for examining these nanoscale circuits in details. We then give a full introduction of characterization techniques and theoretical simulations for molecular electronics. Third, we highlight the major contributions and new concepts of integrating molecular functionalities into electrical circuits. Finally, we provide a critical discussion of limitations and main challenges that still exist for the development of molecular electronics. These analyses should be valuable for deeply understanding charge transport through molecular junctions, the device fabrication process, and the roadmap for future practical molecular electronics.

  14. The Future of the Internet in Science

    NASA Technical Reports Server (NTRS)

    Guice, Jon; Duffy, Robert

    2000-01-01

    How are scientists going to make use of the Internet several years from now? This is a case study of a leading-edge experiment in building a 'virtual institute'-- using electronic communication tools to foster collaboration among geographically dispersed scientists. Our experience suggests: Scientists will want to use web-based document management systems. There will be a demand for Internet-enabled meeting support tools. While internet videoconferencing will have limited value for scientists, webcams will be in great demand as a tool for transmitting pictures of objects and settings, rather than "talking heads." and a significant share of scientists who do fieldwork will embrace mobile voice, data and video communication tools. The setting for these findings is a research consortium called the NASA Astrobiology Institute.

  15. Liquid hydrogen production and commercial demand in the United States

    NASA Technical Reports Server (NTRS)

    Heydorn, Barbara

    1990-01-01

    Kennedy Space Center, the single largest purchaser of liquid hydrogen (LH2) in the United States, evaluated current and anticipated hydrogen production and consumption in the government and commercial sectors. Specific objectives of the study are as follows: (1) identify LH2 producers in the United States and Canada during 1980-1989 period; (2) compile information in expected changes in LH2 production capabilities over the 1990-2000 period; (3) describe how hydrogen is used in each consuming industry and estimate U.S. LH2 consumption for the chemicals, metals, electronics, fats and oil, and glass industries, and report data on a regional basis; (4) estimate historical and future consumption; and (5) assess the influence of international demands on U.S. plants.

  16. Component-Level Electronic-Assembly Repair (CLEAR) Synthetic Instrument Capabilities Assessment and Test Report

    NASA Technical Reports Server (NTRS)

    Oeftering, Richard C.; Bradish, Martin A.

    2011-01-01

    The role of synthetic instruments (SIs) for Component-Level Electronic-Assembly Repair (CLEAR) is to provide an external lower-level diagnostic and functional test capability beyond the built-in-test capabilities of spacecraft electronics. Built-in diagnostics can report faults and symptoms, but isolating the root cause and performing corrective action requires specialized instruments. Often a fault can be revealed by emulating the operation of external hardware. This implies complex hardware that is too massive to be accommodated in spacecraft. The SI strategy is aimed at minimizing complexity and mass by employing highly reconfigurable instruments that perform diagnostics and emulate external functions. In effect, SI can synthesize an instrument on demand. The SI architecture section of this document summarizes the result of a recent program diagnostic and test needs assessment based on the International Space Station. The SI architecture addresses operational issues such as minimizing crew time and crew skill level, and the SI data transactions between the crew and supporting ground engineering searching for the root cause and formulating corrective actions. SI technology is described within a teleoperations framework. The remaining sections describe a lab demonstration intended to show that a single SI circuit could synthesize an instrument in hardware and subsequently clear the hardware and synthesize a completely different instrument on demand. An analysis of the capabilities and limitations of commercially available SI hardware and programming tools is included. Future work in SI technology is also described.

  17. Creating Effective Web-Based Learning Environments: Relevant Research and Practice

    ERIC Educational Resources Information Center

    Wijekumar, Kay

    2005-01-01

    Web-based learning environments are a great asset only if they are designed well and used as intended. The urgency to create courses in response to the growing demand for online learning has resulted in a hurried push to drop PowerPoint notes into Web-based course management systems (WBCMSs), devise an electronic quiz, put together a few…

  18. College Students' Use and Understanding of an Electronic Social Network for Academics, Academic Help Seeking, and Academic Advising

    ERIC Educational Resources Information Center

    Amador, Paul Vincent

    2011-01-01

    The arrival of a new generation of students, known as the Net Generation (Junco, 2010), into colleges and universities has demanded changes to the traditional administrative and support services provided on campuses across the nation. In times of ever-changing technological advances, colleges and universities have begun to utilize new and…

  19. Demand illumination control apparatus

    NASA Technical Reports Server (NTRS)

    Warren, Carl (Inventor); Arline, Jimmie (Inventor); LaPalme, Julius (Inventor)

    1981-01-01

    Solar illuminating compensating apparatus is disclosed whereby the interior of a building is illuminated to a substantially constant, predetermined level of light intensity by a combination of natural illumination from the sun and artificial illumination from electricity wherein the intensity of said artificial illumination is controlled by fully electronic means which increases the level of artificial illumination when the natural illumination is inadequate and vice versa.

  20. Sea-Sponge-like Structure of Nano-Fe3O4 on Skeleton-C with Long Cycle Life under High Rate for Li-Ion Batteries.

    PubMed

    Chen, Shipei; Wu, Qingnan; Wen, Ming; Wu, Qingsheng; Li, Jiaqi; Cui, Yi; Pinna, Nicola; Fan, Yafei; Wu, Tong

    2018-06-13

    To meet the demands of long cycle life under high rate for lithium-ion batteries, the advancement of anode materials with stable structural properties is necessarily demanded. Such promotion needs to design reasonable structure to facilitate the transportation of electron and lithium ions (Li + ). Herein, a novel C/Fe 3 O 4 sea-sponge-like structure was synthesized by ultrasonic spray pyrolysis following thermal decomposition process. On the basis of sea-sponge carbon (SSC) excellences in electronic conductivity and short Li + diffusion pathway, nano-Fe 3 O 4 anchored on stable SSC skeleton can deliver high electrochemical performance with long cycle life under high rate. During electrochemical cycling, well-dispersed nano-Fe 3 O 4 in ∼6 nm not only averts excessive pulverization and is enveloped by solid electrolyte interphase film, but also increases Li + diffusion efficiency. The much improved electrochemical properties showed a capacity of around 460 mAh g -1 at a high rate of 1.5C with a retention rate of 93%, which is maintained without degradation up to 1000 cycles (1C = 1000 mA g -1 ).

  1. Contribution of mental workload to job stress in industrial workers.

    PubMed

    González-Muñoz, Elvia Luz; Gutiérrez-Martínez, Rodolfo E

    2007-01-01

    This study's central objective is to determine how several individual, organizational and ergonomic factors influence the relationship between job stress and mental workload for workers in an electronics company. A cross-sectional study was made as a test of hypotheses regarding that relationship. The sample is composed of 95 workers, of both sexes, from the electronics industry in the metropolitan zone of Guadalajara, Jalisco, Mexico. Ergonomic conditions were evaluated with the Ergonomic Evaluation List, stress was evaluated by administering the SWS-Survey to groups of subjects, and mental workload was evaluated with the NASA-TLX Workload Index. Using Cochran's and Mantel-Haenzsel statistics, the odds ratio for each of the independent variables was {e}stimated as a risk factor for job stress, and analysis was later conducted by means of logistic regression for those risks found to be significant. Of the 95 worker participants, 26.3% presented a high level of job stress and 17.9% of the workers were found to present high levels of mental workload. The results show that working hours, mental demand, temporal demand, and frustration when faced with a given task may be considered risk factors for job stress.

  2. Trends in dermatology practices and the implications for the workforce.

    PubMed

    Ehrlich, Alison; Kostecki, James; Olkaba, Helen

    2017-10-01

    The American Academy of Dermatology (AAD) practice profile surveys have been conducted for more than a decade to gauge trends in our workforce supply and demand. To update the trends and current workforce issues for the field of dermatology. The AAD Practice Profile Survey is sent by both e-mail and postal mail to a random sample of practicing dermatologists who are AAD members. Shifts are noted in the primary practice setting; fewer dermatologists are in solo practice and more are in group practices than in previous years. Teledermatology use trended upward from 7% to 11% between 2012 and 2014. The implementation of electronic health records increased from 51% in 2011 to 70% in 2014. There is potential for response bias and inaccurate self-reporting. Survey responses collected may not be representative of all geographic areas. The demand for dermatology services remains strong. Shifts in the practice setting may be related to increases in overhead costs that are partially associated with the implementation of technology-based medical records. Integration of electronic health records and utilization of telemedicine are increasing. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  3. Electron Impact Ionization of Heavier Ions

    NASA Astrophysics Data System (ADS)

    Saha, B. C.

    2006-10-01

    The electron impact ionization (EII) is a dominant ion creation process in various kinds of plasmas. Hydrogenic atoms occurs not only in plasmas but may also be formed due to radiation effects in many organic and inorganic materials. Apart from its fundamental importance in collisional physics the knowledge of the EII cross sections finds its wide applications in modeling astrophysical and fusion plasmas. So the demand of the EIICS is enormous. It is hard to fulfill such a demand either by experimental or ab initio calculations. Thus various analytical and semi-classical models are employed to generate accurate EII cross sections. We report here a modified version [1] of the Bell et. al. equations [2] including both the ionic and relativistic corrections (MBELL). We generalize the MBELL parameters for treating the dependency of the orbital quantum numbers nl; evaluating cross sections for various species at different energies tests the accuracy of the procedure. Detail will be presented at the meeting. [1] A. K. F. Haque, M. A. Uddin, A. K. Basak, K. R. Karim and B. C. Saha, Phys. Rev. A73, 052703 (2006). [2] K. L. Bell, H. B. Gilbody, J. G. Hughes, A. E. Kingston, and F. J. Smith, J. Phys. Chem. Ref. Data 12, 891 (1983).

  4. Patterned low temperature copper-rich deposits using inkjet printing

    NASA Astrophysics Data System (ADS)

    Rozenberg, Gregor G.; Bresler, Eric; Speakman, Stuart P.; Jeynes, Chris; Steinke, Joachim H. G.

    2002-12-01

    A PZT piezoelectric ceramic research drop-on-demand inkjet print head operating in bend mode was used as a means of delivering a copper precursor, vinyltrimethylsilane copper (+1) hexafluoroacetylacetonate, in a controlled and placement accurate fashion. The reagent disproportionates at low temperature (<200 °C), to deposit copper on glass. These deposits are shown to be more than 90% copper by weight by electron probe microanalysis and microbeam Rutherford backscattering spectroscopy. Microscopy shows a deposit diameter and three-dimensional profile that suggests a complex deposition and conversion mechanism. Our findings represent an important step towards the manufacture of electronic devices by entirely nonlithographic means.

  5. Use of aquatic macrophytes in treating electronics manufacturing wastewater in Guadalajara, Mexico

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leslie, C.I.; Jackson, J.D.

    1996-12-31

    This paper discusses an industrial wastewater treatment project performed by Kleinfelder Mexico for an electronics manufacturer located in Guadalajara, Mexico. The industrial wastewater had a moderately high concentration of biochemical oxygen demand (BOD), total suspended solids (TSS), and grease and oil. Metals concentration was low, with only zinc exceeding regulatory standards. The use of aquatic macrophytes (namely Eichhornia crassipes) was considered along with conventional wastewater treatment options. An aquatic macrophyte wastewater treatment system was found to have numerous advantages over a conventional extended aeration package plant. These advantages include less required capital, an appreciation of investment, and lower operations andmore » maintenance costs.« less

  6. Pressure scanning choices - Rotary vs electronic

    NASA Astrophysics Data System (ADS)

    Pemberton, Addison

    The choices available for present-day pressure scanning applications are described. Typical pressure scanning applications include wind tunnels, flight testing, turbine engine testing, process control, and laboratory/bench testing. The Scanivalve concept is discussed and it is noted that their use eliminates the cost of multiple individual pressure transducers and their signal conditioners as well as associated wiring for each pressure to be measured. However, they are limited to a maximum acquisition speed of 20 ports/sec/scanner. The advantages of electronic pressure scanners include in-situ calibration on demand, fast data acquisition speed, and high reliability. On the other hand, they are three times more expensive than rotary Scanivalves.

  7. Accelerators for E-beam and X-ray processing

    NASA Astrophysics Data System (ADS)

    Auslender, V. L.; Bryazgin, A. A.; Faktorovich, B. L.; Gorbunov, V. A.; Kokin, E. N.; Korobeinikov, M. V.; Krainov, G. S.; Lukin, A. N.; Maximov, S. A.; Nekhaev, V. E.; Panfilov, A. D.; Radchenko, V. N.; Tkachenko, V. O.; Tuvik, A. A.; Voronin, L. A.

    2002-03-01

    During last years the demand for pasteurization and desinsection of various food products (meat, chicken, sea products, vegetables, fruits, etc.) had increased. The treatment of these products in industrial scale requires the usage of powerful electron accelerators with energy 5-10 MeV and beam power at least 50 kW or more. The report describes the ILU accelerators with energy range up to 10 MeV and beam power up to 150 kW.The different irradiation schemes in electron beam and X-ray modes for various products are described. The design of the X-ray converter and 90° beam bending system are also given.

  8. Microfluidic electronics.

    PubMed

    Cheng, Shi; Wu, Zhigang

    2012-08-21

    Microfluidics, a field that has been well-established for several decades, has seen extensive applications in the areas of biology, chemistry, and medicine. However, it might be very hard to imagine how such soft microfluidic devices would be used in other areas, such as electronics, in which stiff, solid metals, insulators, and semiconductors have previously dominated. Very recently, things have radically changed. Taking advantage of native properties of microfluidics, advances in microfluidics-based electronics have shown great potential in numerous new appealing applications, e.g. bio-inspired devices, body-worn healthcare and medical sensing systems, and ergonomic units, in which conventional rigid, bulky electronics are facing insurmountable obstacles to fulfil the demand on comfortable user experience. Not only would the birth of microfluidic electronics contribute to both the microfluidics and electronics fields, but it may also shape the future of our daily life. Nevertheless, microfluidic electronics are still at a very early stage, and significant efforts in research and development are needed to advance this emerging field. The intention of this article is to review recent research outcomes in the field of microfluidic electronics, and address current technical challenges and issues. The outlook of future development in microfluidic electronic devices and systems, as well as new fabrication techniques, is also discussed. Moreover, the authors would like to inspire both the microfluidics and electronics communities to further exploit this newly-established field.

  9. Treatment of surfaces with low-energy electrons

    NASA Astrophysics Data System (ADS)

    Frank, L.; Mikmeková, E.; Lejeune, M.

    2017-06-01

    Electron-beam-induced deposition of various materials from suitable precursors has represented an established branch of nanotechnology for more than a decade. A specific alternative is carbon deposition on the basis of hydrocarbons as precursors that has been applied to grow various nanostructures including masks for subsequent technological steps. Our area of study was unintentional electron-beam-induced carbon deposition from spontaneously adsorbed hydrocarbon molecules. This process traditionally constitutes a challenge for scanning electron microscopy practice preventing one from performing any true surface studies outside an ultrahigh vacuum and without in-situ cleaning of samples, and also jeopardising other electron-optical devices such as electron beam lithographs. Here we show that when reducing the energy of irradiating electrons sufficiently, the e-beam-induced deposition can be converted to e-beam-induced release causing desorption of hydrocarbons and ultimate cleaning of surfaces in both an ultrahigh and a standard high vacuum. Using series of experiments with graphene samples, we demonstrate fundamental features of e-beam-induced desorption and present results of checks for possible radiation damage using Raman spectroscopy that led to optimisation of the electron energy for damage-free cleaning. The method of preventing carbon contamination described here paves the way for greatly enhanced surface sensitivity of imaging and substantially reduced demands on vacuum systems for nanotechnological applications.

  10. Research on the EDM Technology for Micro-holes at Complex Spatial Locations

    NASA Astrophysics Data System (ADS)

    Y Liu, J.; Guo, J. M.; Sun, D. J.; Cai, Y. H.; Ding, L. T.; Jiang, H.

    2017-12-01

    For the demands on machining micro-holes at complex spatial location, several key technical problems are conquered such as micro-Electron Discharge Machining (micro-EDM) power supply system’s development, the host structure’s design and machining process technical. Through developing low-voltage power supply circuit, high-voltage circuit, micro and precision machining circuit and clearance detection system, the narrow pulse and high frequency six-axis EDM machining power supply system is developed to meet the demands on micro-hole discharging machining. With the method of combining the CAD structure design, CAE simulation analysis, modal test, ODS (Operational Deflection Shapes) test and theoretical analysis, the host construction and key axes of the machine tool are optimized to meet the position demands of the micro-holes. Through developing the special deionized water filtration system to make sure that the machining process is stable enough. To verify the machining equipment and processing technical developed in this paper through developing the micro-hole’s processing flow and test on the real machine tool. As shown in the final test results: the efficient micro-EDM machining pulse power supply system, machine tool host system, deionized filtration system and processing method developed in this paper meet the demands on machining micro-holes at complex spatial locations.

  11. Two-Electron Transfer Pathways.

    PubMed

    Lin, Jiaxing; Balamurugan, D; Zhang, Peng; Skourtis, Spiros S; Beratan, David N

    2015-06-18

    The frontiers of electron-transfer chemistry demand that we develop theoretical frameworks to describe the delivery of multiple electrons, atoms, and ions in molecular systems. When electrons move over long distances through high barriers, where the probability for thermal population of oxidized or reduced bridge-localized states is very small, the electrons will tunnel from the donor (D) to acceptor (A), facilitated by bridge-mediated superexchange interactions. If the stable donor and acceptor redox states on D and A differ by two electrons, it is possible that the electrons will propagate coherently from D to A. While structure-function relations for single-electron superexchange in molecules are well established, strategies to manipulate the coherent flow of multiple electrons are largely unknown. In contrast to one-electron superexchange, two-electron superexchange involves both one- and two-electron virtual intermediate states, the number of virtual intermediates increases very rapidly with system size, and multiple classes of pathways interfere with one another. In the study described here, we developed simple superexchange models for two-electron transfer. We explored how the bridge structure and energetics influence multielectron superexchange, and we compared two-electron superexchange interactions to single-electron superexchange. Multielectron superexchange introduces interference between singly and doubly oxidized (or reduced) bridge virtual states, so that even simple linear donor-bridge-acceptor systems have pathway topologies that resemble those seen for one-electron superexchange through bridges with multiple parallel pathways. The simple model systems studied here exhibit a richness that is amenable to experimental exploration by manipulating the multiple pathways, pathway crosstalk, and changes in the number of donor and acceptor species. The features that emerge from these studies may assist in developing new strategies to deliver multiple electrons in condensed-phase redox systems, including multiple-electron redox species, multimetallic/multielectron redox catalysts, and multiexciton excited states.

  12. Nonvolatile memory behavior of nanocrystalline cellulose/graphene oxide composite films

    NASA Astrophysics Data System (ADS)

    Valentini, L.; Cardinali, M.; Fortunati, E.; Kenny, J. M.

    2014-10-01

    With the continuous advance of modern electronics, the demand for nonvolatile memory cells rapidly grows. In order to develop post-silicon electronic devices, it is necessary to find innovative solutions to the eco-sustainability problem of materials for nonvolatile memory cells. In this work, we realized a resistive memory device based on graphene oxide (GO) and GO/cellulose nanocrystals (CNC) thin films. Aqueous solutions of GO and GO with CNC have been prepared and drop cast between two metal electrodes. Such thin-film based devices showed a transition between low and high conductivity states upon the forward and backward sweeping of an external electric field. This reversible current density transition behavior demonstrates a typical memory characteristic. The obtained results open an easy route for electronic information storage based on the integration of nanocrystalline cellulose onto graphene based devices.

  13. Strongly Correlated Electron Systems: An Operatorial Perspective

    NASA Astrophysics Data System (ADS)

    Di Ciolo, Andrea; Avella, Adolfo

    2018-05-01

    We discuss the operatorial approach to the study of strongly correlated electron systems and show how the exact solution of target models on small clusters chosen ad-hoc (minimal models) can suggest very efficient bulk approximations. We use the Hubbard model as case study (target model) and we analyze and discuss the crucial role of spin fluctuations in its 2-site realization (minimal model). Accordingly, we devise a novel three-pole approximation for the 2D case, including in the basic field an operator describing the dressing of the electronic one by the nearest-neighbor spin-fluctuations. Such a solution is in very good agreement with the exact one in the minimal model (2-site case) and performs very well once compared to advanced (semi-)numerical methods in the 2D case, being by far less computational-resource demanding.

  14. Advanced electron microscopy characterization of nanomaterials for catalysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Su, Dong

    Transmission electron microscopy (TEM) has become one of the most powerful techniques in the fields of material science, inorganic chemistry and nanotechnology. In terms of resolutions, advanced TEM may reach a high spatial resolution of 0.05 nm, a high energy-resolution of 7 meV. In addition, in situ TEM can help researcher to image the process happened within 1 ms. This paper reviews the recent technical approaches of applying advanced TEM characterization on nanomaterials for catalysis. The text is organized according to the demanded information of nanocrystals from the perspective of application: for example, size, composition, phase, strain, and morphology. Themore » electron beam induced effect and in situ TEM are also introduced. As a result, I hope this review can help the scientists in related fields to take advantage of advanced TEM to their own researches.« less

  15. Advanced electron microscopy characterization of nanomaterials for catalysis

    DOE PAGES

    Su, Dong

    2017-04-01

    Transmission electron microscopy (TEM) has become one of the most powerful techniques in the fields of material science, inorganic chemistry and nanotechnology. In terms of resolutions, advanced TEM may reach a high spatial resolution of 0.05 nm, a high energy-resolution of 7 meV. In addition, in situ TEM can help researcher to image the process happened within 1 ms. This paper reviews the recent technical approaches of applying advanced TEM characterization on nanomaterials for catalysis. The text is organized according to the demanded information of nanocrystals from the perspective of application: for example, size, composition, phase, strain, and morphology. Themore » electron beam induced effect and in situ TEM are also introduced. As a result, I hope this review can help the scientists in related fields to take advantage of advanced TEM to their own researches.« less

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Jaekyun; Kim, Myung -Gil; Kim, Jaehyun

    The success of silicon based high density integrated circuits ignited explosive expansion of microelectronics. Although the inorganic semiconductors have shown superior carrier mobilities for conventional high speed switching devices, the emergence of unconventional applications, such as flexible electronics, highly sensitive photosensors, large area sensor array, and tailored optoelectronics, brought intensive research on next generation electronic materials. The rationally designed multifunctional soft electronic materials, organic and carbon-based semiconductors, are demonstrated with low-cost solution process, exceptional mechanical stability, and on-demand optoelectronic properties. Unfortunately, the industrial implementation of the soft electronic materials has been hindered due to lack of scalable fine-patterning methods. Inmore » this report, we demonstrated facile general route for high throughput sub-micron patterning of soft materials, using spatially selective deep-ultraviolet irradiation. For organic and carbon-based materials, the highly energetic photons (e.g. deep-ultraviolet rays) enable direct photo-conversion from conducting/semiconducting to insulating state through molecular dissociation and disordering with spatial resolution down to a sub-μm-scale. As a result, the successful demonstration of organic semiconductor circuitry promise our result proliferate industrial adoption of soft materials for next generation electronics.« less

  17. A high turndown, ultra low emission low swirl burner for natural gas, on-demand water heaters

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rapp, Vi H.; Cheng, Robert K.; Therkelsen, Peter L.

    Previous research has shown that on-demand water heaters are, on average, approximately 37% more efficient than storage water heaters. However, approximately 98% of water heaters in the U.S. use storage water heaters while the remaining 2% are on-demand. A major market barrier to deployment of on-demand water heaters is their high retail cost, which is due in part to their reliance on multi-stage burner banks that require complex electronic controls. This project aims to research and develop a cost-effective, efficient, ultra-low emission burner for next generation natural gas on-demand water heaters in residential and commercial buildings. To meet these requirements,more » researchers at the Lawrence Berkeley National Laboratory (LBNL) are adapting and testing the low-swirl burner (LSB) technology for commercially available on-demand water heaters. In this report, a low-swirl burner is researched, developed, and evaluated to meet targeted on-demand water heater performance metrics. Performance metrics for a new LSB design are identified by characterizing performance of current on-demand water heaters using published literature and technical specifications, and through experimental evaluations that measure fuel consumption and emissions output over a range of operating conditions. Next, target metrics and design criteria for the LSB are used to create six 3D printed prototypes for preliminary investigations. Prototype designs that proved the most promising were fabricated out of metal and tested further to evaluate the LSB’s full performance potential. After conducting a full performance evaluation on two designs, we found that one LSB design is capable of meeting or exceeding almost all the target performance metrics for on-demand water heaters. Specifically, this LSB demonstrated flame stability when operating from 4.07 kBTU/hr up to 204 kBTU/hr (50:1 turndown), compliance with SCAQMD Rule 1146.2 (14 ng/J or 20 ppm NOX @ 3% O2), and lower CO emissions than state-of-the art water heaters. Overall, the results from this research show that the LSB could provide a simple, low cost burner solution for significantly extending operating range of on-demand water heaters while providing low NOX and CO emissions.« less

  18. The water-water cycle is a major electron sink in Camellia species when CO2 assimilation is restricted.

    PubMed

    Cai, Yan-Fei; Yang, Qiu-Yun; Li, Shu-Fa; Wang, Ji-Hua; Huang, Wei

    2017-03-01

    The water-water cycle (WWC) is thought to dissipate excess excitation energy and balance the ATP/NADPH energy budget under some conditions. However, the importance of the WWC in photosynthetic regulation remains controversy. We observed that three Camellia cultivars exhibited high rates of photosynthetic electron flow under high light when photosynthesis was restricted. We thus tested the hypothesis that the WWC is a major electron sink in the three Camellia cultivars when CO 2 assimilation is restricted. Light response curves indicated that the WWC was strongly increased with photorespiration and was positively correlated with extra ATP supplied from other flexible mechanisms excluding linear electron flow, implying that the WWC is an important alternative electron sink to balance ATP/NADPH energy demand for sustaining photorespiration in Camellia cultivars. Interestingly, when photosynthesis was depressed by the decreases in stomatal and mesophyll conductance, the rates of photosynthetic electron flow through photosystem II declined slightly and the rates of WWC was enhanced. Furthermore, the increased electron flow of WWC was positively correlated with the ratio of Rubisco oxygenation to carboxylation, supporting the involvement of alternative electron flow in balancing the ATP/NADPH energy budget. We propose that the WWC is a crucial electron sink to regulate ATP/NADPH energy budget and dissipate excess energy excitation in Camellia species when CO 2 assimilation is restricted. Copyright © 2017. Published by Elsevier B.V.

  19. Three-Dimensional Printed Poly(vinyl alcohol) Substrate with Controlled On-Demand Degradation for Transient Electronics.

    PubMed

    Yoon, Jinsu; Han, Jungmin; Choi, Bongsik; Lee, Yongwoo; Kim, Yeamin; Park, Jinhee; Lim, Meehyun; Kang, Min-Ho; Kim, Dae Hwan; Kim, Dong Myong; Kim, Sungho; Choi, Sung-Jin

    2018-05-25

    Electronics that degrade after stable operation for a desired operating time, called transient electronics, are of great interest in many fields, including biomedical implants, secure memory devices, and environmental sensors. Thus, the development of transient materials is critical for the advancement of transient electronics and their applications. However, previous reports have mostly relied on achieving transience in aqueous solutions, where the transience time is largely predetermined based on the materials initially selected at the beginning of the fabrication. Therefore, accurate control of the transience time is difficult, thereby limiting their application. In this work, we demonstrate transient electronics based on a water-soluble poly(vinyl alcohol) (PVA) substrate on which carbon nanotube (CNT)-based field-effect transistors were fabricated. We regulated the structural parameters of the PVA substrate using a three-dimensional (3D) printer to accurately control and program the transience time of the PVA substrate in water. The 3D printing technology can produce complex objects directly, thus enabling the efficient fabrication of a transient substrate with a prescribed and controlled transience time. In addition, the 3D printer was used to develop a facile method for the selective and partial destruction of electronics.

  20. Commercial printing and electronic color printing

    NASA Astrophysics Data System (ADS)

    Webb, Joseph W.

    1995-04-01

    Technologies such as Xeikon, Indigo, and the Heidelberg/Presstek GTO-DI can change both the way print buyers may purchase printed material and the way printers and trade services respond to changing demands. Our recent study surveys the graphic arts industry for their current views of these new products and provides forecasts of installations and usage with breakdowns by market segment and size of firm. The acceptance of desktop publishing and electronic prepress have not only paved the way for a totally electronic printing process, but it has broadened the base of people who develop color originals for reproduction. Electronic printing adds the ability to customize jobs on the fly. How print providers will respond to the impact of electronic color printing depends on how each firm perceives the 'threat.' Most printing companies are run by entrepreneurial individuals who have, as their highest priority, their own economic survival. Service bureaus are already looking at electronic color printing as yet another way to differentiate their businesses. The study was based on a mail survey with 682 responses from graphic arts firms, interviews with printers, suppliers, associations and industry executives, and detailed secondary research. Results of a new survey in progress in January 1995 is also presented.

  1. Scalable Sub-micron Patterning of Organic Materials Toward High Density Soft Electronics

    PubMed Central

    Kim, Jaekyun; Kim, Myung-Gil; Kim, Jaehyun; Jo, Sangho; Kang, Jingu; Jo, Jeong-Wan; Lee, Woobin; Hwang, Chahwan; Moon, Juhyuk; Yang, Lin; Kim, Yun-Hi; Noh, Yong-Young; Yun Jaung, Jae; Kim, Yong-Hoon; Kyu Park, Sung

    2015-01-01

    The success of silicon based high density integrated circuits ignited explosive expansion of microelectronics. Although the inorganic semiconductors have shown superior carrier mobilities for conventional high speed switching devices, the emergence of unconventional applications, such as flexible electronics, highly sensitive photosensors, large area sensor array, and tailored optoelectronics, brought intensive research on next generation electronic materials. The rationally designed multifunctional soft electronic materials, organic and carbon-based semiconductors, are demonstrated with low-cost solution process, exceptional mechanical stability, and on-demand optoelectronic properties. Unfortunately, the industrial implementation of the soft electronic materials has been hindered due to lack of scalable fine-patterning methods. In this report, we demonstrated facile general route for high throughput sub-micron patterning of soft materials, using spatially selective deep-ultraviolet irradiation. For organic and carbon-based materials, the highly energetic photons (e.g. deep-ultraviolet rays) enable direct photo-conversion from conducting/semiconducting to insulating state through molecular dissociation and disordering with spatial resolution down to a sub-μm-scale. The successful demonstration of organic semiconductor circuitry promise our result proliferate industrial adoption of soft materials for next generation electronics. PMID:26411932

  2. Electronic signatures for long-lasting storage purposes in electronic archives.

    PubMed

    Pharow, Peter; Blobel, Bernd

    2005-03-01

    Communication and co-operation in healthcare and welfare require a certain set of trusted third party (TTP) services describing both status and relation of communicating principals as well as their corresponding keys and attributes. Additional TTP services are needed to provide trustworthy information about dynamic issues of communication and co-operation such as time and location of processes, workflow relations, and system behaviour. Legal and ethical requirements demand securely stored patient information and well-defined access rights. Among others, electronic signatures based on asymmetric cryptography are important means for securing the integrity of a message or file as well as for accountability purposes including non-repudiation of both origin and receipt. Electronic signatures along with certified time stamps or time signatures are especially important for electronic archives in general, electronic health records (EHR) in particular, and especially for typical purposes of long-lasting storage. Apart from technical storage problems (e.g. lifetime of the storage devices, interoperability of retrieval and presentation software), this paper identifies mechanisms of e.g. re-signing and re-stamping of data items, files, messages, sets of archived items or documents, archive structures, and even whole archives.

  3. A large-area wireless power-transmission sheet using printed organic transistors and plastic MEMS switches.

    PubMed

    Sekitani, Tsuyoshi; Takamiya, Makoto; Noguchi, Yoshiaki; Nakano, Shintaro; Kato, Yusaku; Sakurai, Takayasu; Someya, Takao

    2007-06-01

    The electronics fields face serious problems associated with electric power; these include the development of ecologically friendly power-generation systems and ultralow-power-consuming circuits. Moreover, there is a demand for developing new power-transmission methods in the imminent era of ambient electronics, in which a multitude of electronic devices such as sensor networks will be used in our daily life to enhance security, safety and convenience. We constructed a sheet-type wireless power-transmission system by using state-of-the-art printing technologies using advanced electronic functional inks. This became possible owing to recent progress in organic semiconductor technologies; the diversity of chemical syntheses and processes on organic materials has led to a new class of organic semiconductors, dielectric layers and metals with excellent electronic functionalities. The new system directly drives electronic devices by transmitting power of the order of tens of watts without connectors, thereby providing an easy-to-use and reliable power source. As all of the components are manufactured on plastic films, it is easy to place the wireless power-transmission sheet over desks, floors, walls and any other location imaginable.

  4. Scalable sub-micron patterning of organic materials toward high density soft electronics

    DOE PAGES

    Kim, Jaekyun; Kim, Myung -Gil; Kim, Jaehyun; ...

    2015-09-28

    The success of silicon based high density integrated circuits ignited explosive expansion of microelectronics. Although the inorganic semiconductors have shown superior carrier mobilities for conventional high speed switching devices, the emergence of unconventional applications, such as flexible electronics, highly sensitive photosensors, large area sensor array, and tailored optoelectronics, brought intensive research on next generation electronic materials. The rationally designed multifunctional soft electronic materials, organic and carbon-based semiconductors, are demonstrated with low-cost solution process, exceptional mechanical stability, and on-demand optoelectronic properties. Unfortunately, the industrial implementation of the soft electronic materials has been hindered due to lack of scalable fine-patterning methods. Inmore » this report, we demonstrated facile general route for high throughput sub-micron patterning of soft materials, using spatially selective deep-ultraviolet irradiation. For organic and carbon-based materials, the highly energetic photons (e.g. deep-ultraviolet rays) enable direct photo-conversion from conducting/semiconducting to insulating state through molecular dissociation and disordering with spatial resolution down to a sub-μm-scale. As a result, the successful demonstration of organic semiconductor circuitry promise our result proliferate industrial adoption of soft materials for next generation electronics.« less

  5. Application of Temperature-Controlled Thermal Atomization for Printing Electronics in Space

    NASA Technical Reports Server (NTRS)

    Wu, Chih-Hao; Thompson, Furman V.

    2017-01-01

    Additive Manufacturing (AM) is a technology that builds three dimensional objects by adding material layer-upon-layer throughout the fabrication process. The Electrical, Electronic and Electromechanical (EEE) parts packaging group at Marshall Space Flight Center (MSFC) is investigating how various AM and 3D printing processes can be adapted to the microgravity environment of space to enable on demand manufacturing of electronics. The current state-of-the art processes for accomplishing the task of printing electronics through non-contact, direct-write means rely heavily on the process of atomization of liquid inks into fine aerosols to be delivered ultimately to a machine's print head and through its nozzle. As a result of cumulative International Space Station (ISS) research into the behaviors of fluids in zero-gravity, our experience leads us to conclude that the direct adaptation of conventional atomization processes will likely fall short and alternative approaches will need to be explored. In this report, we investigate the development of an alternative approach to atomizing electronic materials by way of thermal atomization, to be used in place of conventional aerosol generation and delivery processes for printing electronics in space.

  6. Design rules for charge-transport efficient host materials for phosphorescent organic light-emitting diodes.

    PubMed

    May, Falk; Al-Helwi, Mustapha; Baumeier, Björn; Kowalsky, Wolfgang; Fuchs, Evelyn; Lennartz, Christian; Andrienko, Denis

    2012-08-22

    The use of blue phosphorescent emitters in organic light-emitting diodes (OLEDs) imposes demanding requirements on a host material. Among these are large triplet energies, the alignment of levels with respect to the emitter, the ability to form and sustain amorphous order, material processability, and an adequate charge carrier mobility. A possible design strategy is to choose a π-conjugated core with a high triplet level and to fulfill the other requirements by using suitable substituents. Bulky substituents, however, induce large spatial separations between conjugated cores, can substantially reduce intermolecular electronic couplings, and decrease the charge mobility of the host. In this work we analyze charge transport in amorphous 2,8-bis(triphenylsilyl)dibenzofuran, an electron-transporting material synthesized to serve as a host in deep-blue OLEDs. We show that mesomeric effects delocalize the frontier orbitals over the substituents recovering strong electronic couplings and lowering reorganization energies, especially for electrons, while keeping energetic disorder small. Admittance spectroscopy measurements reveal that the material has indeed a high electron mobility and a small Poole-Frenkel slope, supporting our conclusions. By linking electronic structure, molecular packing, and mobility, we provide a pathway to the rational design of hosts with high charge mobilities.

  7. Gaseous 83mKr generator of monoenergetic electrons based on 83Rb deposited in zeolite

    NASA Astrophysics Data System (ADS)

    Sentkerestiová, J.; Vénos, D.; Slezák, M.

    2017-09-01

    The gaseous 83mKr electron source is currently used in neutrino mass experiments KATRIN and Project 8, dark matter experiments XENON, LUX and DarkSide, and ALICE (CERN) experiment. The main attractive features of this radioactive noble gas are its monoenergetic conversion electrons with well known energies and a half-life of 1.8 h, which is short enough to avoid any long-lasting contamination of the system. The long half-life of the mother 83Rb isotope (T1/2 = 86.2 d) enables more time demanding measurement. Particularly, in the neutrino mass experiments with gaseous tritium in which the 83mKr is applied in the same manner as the tritium, the K-32 conversion electrons with energy conveniently close to the beta spectrum endpoint represent an important test and calibration tool. Here, the design and characteristics of the gaseous 83mKr generator, including the 83mKr source itself, for KATRIN (KArlsruhe TRItium Neutrino) experiment are presented.

  8. Measurement of transverse emittance and coherence of double-gate field emitter array cathodes

    PubMed Central

    Tsujino, Soichiro; Das Kanungo, Prat; Monshipouri, Mahta; Lee, Chiwon; Miller, R.J. Dwayne

    2016-01-01

    Achieving small transverse beam emittance is important for high brightness cathodes for free electron lasers and electron diffraction and imaging experiments. Double-gate field emitter arrays with on-chip focussing electrode, operating with electrical switching or near infrared laser excitation, have been studied as cathodes that are competitive with photocathodes excited by ultraviolet lasers, but the experimental demonstration of the low emittance has been elusive. Here we demonstrate this for a field emitter array with an optimized double-gate structure by directly measuring the beam characteristics. Further we show the successful application of the double-gate field emitter array to observe the low-energy electron beam diffraction from suspended graphene in minimal setup. The observed low emittance and long coherence length are in good agreement with theory. These results demonstrate that our all-metal double-gate field emitters are highly promising for applications that demand extremely low-electron bunch-phase space volume and large transverse coherence. PMID:28008918

  9. Measurement of transverse emittance and coherence of double-gate field emitter array cathodes

    NASA Astrophysics Data System (ADS)

    Tsujino, Soichiro; Das Kanungo, Prat; Monshipouri, Mahta; Lee, Chiwon; Miller, R. J. Dwayne

    2016-12-01

    Achieving small transverse beam emittance is important for high brightness cathodes for free electron lasers and electron diffraction and imaging experiments. Double-gate field emitter arrays with on-chip focussing electrode, operating with electrical switching or near infrared laser excitation, have been studied as cathodes that are competitive with photocathodes excited by ultraviolet lasers, but the experimental demonstration of the low emittance has been elusive. Here we demonstrate this for a field emitter array with an optimized double-gate structure by directly measuring the beam characteristics. Further we show the successful application of the double-gate field emitter array to observe the low-energy electron beam diffraction from suspended graphene in minimal setup. The observed low emittance and long coherence length are in good agreement with theory. These results demonstrate that our all-metal double-gate field emitters are highly promising for applications that demand extremely low-electron bunch-phase space volume and large transverse coherence.

  10. Local light-induced magnetization using nanodots and chiral molecules.

    PubMed

    Dor, Oren Ben; Morali, Noam; Yochelis, Shira; Baczewski, Lech Tomasz; Paltiel, Yossi

    2014-11-12

    With the increasing demand for miniaturization, nanostructures are likely to become the primary components of future integrated circuits. Different approaches are being pursued toward achieving efficient electronics, among which are spin electronics devices (spintronics). In principle, the application of spintronics should result in reducing the power consumption of electronic devices. Recently a new, promising, effective approach for spintronics has emerged, using spin selectivity in electron transport through chiral molecules. In this work, using chiral molecules and nanocrystals, we achieve local spin-based magnetization generated optically at ambient temperatures. Through the chiral layer, a spin torque can be transferred without permanent charge transfer from the nanocrystals to a thin ferromagnetic layer, creating local perpendicular magnetization. We used Hall sensor configuration and atomic force microscopy (AFM) to measure the induced local magnetization. At low temperatures, anomalous spin Hall effects were measured using a thin Ni layer. The results may lead to optically controlled spintronics logic devices that will enable low power consumption, high density, and cheap fabrication.

  11. Oxidase catalysis via aerobically generated hypervalent iodine intermediates

    NASA Astrophysics Data System (ADS)

    Maity, Asim; Hyun, Sung-Min; Powers, David C.

    2018-02-01

    The development of sustainable oxidation chemistry demands strategies to harness O2 as a terminal oxidant. Oxidase catalysis, in which O2 serves as a chemical oxidant without necessitating incorporation of oxygen into reaction products, would allow diverse substrate functionalization chemistry to be coupled to O2 reduction. Direct O2 utilization suffers from intrinsic challenges imposed by the triplet ground state of O2 and the disparate electron inventories of four-electron O2 reduction and two-electron substrate oxidation. Here, we generate hypervalent iodine reagents—a broadly useful class of selective two-electron oxidants—from O2. This is achieved by intercepting reactive intermediates of aldehyde autoxidation to aerobically generate hypervalent iodine reagents for a broad array of substrate oxidation reactions. The use of aryl iodides as mediators of aerobic oxidation underpins an oxidase catalysis platform that couples substrate oxidation directly to O2 reduction. We anticipate that aerobically generated hypervalent iodine reagents will expand the scope of aerobic oxidation chemistry in chemical synthesis.

  12. Investigating a Drop-on-Demand Microdispenser for Standardized Sample Preparation

    DTIC Science & Technology

    2011-09-01

    including the printing of photodiodes , polymer and protein arrays , and in electronics manufacturing (4–7). These applications benefit from the wide...photograph of an array of microdroplets demonstrates a more even sample dispersion when sample is dispensed with a DOD microdispenser... threats encountered. A variety of techniques that offer temporary alternatives have been employed, including drop-and-dry (dropcasting) and spray

  13. 76 FR 20892 - Prohibition Against Payment of Interest on Demand Deposits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-14

    ... comments may also be viewed electronically or in paper in Room MP-500 of the Board's Martin Building (20th... Dodd-Frank Act repeals Section 19(i) of the Act in its entirety, effective one year from the date of... typeface with a font size of 10 or 12; this will enable the Board to convert text submitted in paper form...

  14. An Analysis of Unplanned Requirements and Their Impact on the Naval Electronic Systems Command

    DTIC Science & Technology

    1976-06-01

    Evaluation Repair Turnaround Time Ship Alteration Management Information System Shipbuilding and Conversion, Navy Standard Hardware Program Ships Parts...pending assigment of a NSN. Such equipments would have little opportunity to accumulate any demand history. Secondly, the relatively low percentage of...mentioned above. Unfortunately, sufficient historical information was not available to fully accomplish this goal. In the case of assets acquired from

  15. Mobile Technology: Creation and Use of an iBook to Teach the Anatomy of the Brachial Plexus

    ERIC Educational Resources Information Center

    Stewart, Stuart; Choudhury, Bipasha

    2015-01-01

    In an era of digitally connected students, there is a demand for academic material to be delivered through electronic mobile devices and not just through traditional methods such as lectures and tutorials. A digital interactive book--iBook (for use on the Apple iPad)--was created to teach undergraduate anatomical science students (n?=?26) four key…

  16. Cryogenic Cooling of Infrared Electronics

    DTIC Science & Technology

    1986-05-01

    thermally driven, offers the potential of reducing operating and maintenance costs over the entire life cycle because of advan- tages in reduced wear due to...on demand. In addition to conventional mechanical cycles, it is possible to incorporate thermal, thermoelectric, and magnetic processes avoiding wear ...Considerable effort has been expended in improving the components of the Stirling cryocooler, especially in terms of minimizing the wear of the

  17. Mineral resource of the month: cobalt

    USGS Publications Warehouse

    Shedd, Kim B.

    2009-01-01

    Cobalt is a metal used in numerous commercial, industrial and military applications. On a global basis, the leading use of cobalt is in rechargeable lithium-ion, nickel-cadmium and nickel-metal hydride battery electrodes. Cobalt use has grown rapidly since the early 1990s, with the development of new battery technologies and an increase in demand for portable electronics such as cell phones, laptop computers and cordless power tools.

  18. Computers & Composing: How the New Technologies Are Changing Writing. Studies in Writing & Rhetoric Series.

    ERIC Educational Resources Information Center

    Halpern, Jeanne W.; Liggett, Sarah

    Intended to (1) acquaint teachers with the potential of computers, (2) show them what changes writers may have to make in their composing habits, and (3) inform teachers of the changes they may have to make in course syllabi to prepare students for the demands of the electronic world, this book examines the impact of technology on composition…

  19. Cellulose nanocrystal and poly[di(ethylene glycol) adipate] blend for tunable lens

    NASA Astrophysics Data System (ADS)

    Ko, Hyun-U.; Kim, Hyun Chan; Li, Yaguang; Kim, Sang Youn; Kim, Jaehwan

    2016-04-01

    In these days, consumer electronics and medical device for optical diagnosis are minimalized and mobilized. The focusing part is one of crucial parts of optical diagnosis systems to reduce the size and weight. Thus, demand for tunable lens that change the focus itself is increased. To meet the demand, many tunable lens has been studied by utilizing smart materials that responded under mechanical, magnetic, optical, thermal, chemical, electrical or electrochemical stimuli. This paper reports a cellulose nanocrystal (CNC) and poly[di(ethylene glycol) adipate] (PDEGA) blend that is able to respond under electromechanical stimulus. The preparation of CNC/PDEGA and its characterization are illustrated and its actuation behavior is tested . Because the material has high dielectric constant and high reflection index, it is good candidate material for tunable lens.

  20. Spacecraft optical disk recorder memory buffer control

    NASA Technical Reports Server (NTRS)

    Hodson, Robert F.

    1993-01-01

    This paper discusses the research completed under the NASA-ASEE summer faculty fellowship program. The project involves development of an Application Specific Integrated Circuit (ASIC) to be used as a Memory Buffer Controller (MBC) in the Spacecraft Optical Disk System (SODR). The SODR system has demanding capacity and data rate specifications requiring specialized electronics to meet processing demands. The system is being designed to support Gigabit transfer rates with Terabit storage capability. The complete SODR system is designed to exceed the capability of all existing mass storage systems today. The ASIC development for SODR consist of developing a 144 pin CMOS device to perform format conversion and data buffering. The final simulations of the MBC were completed during this summer's NASA-ASEE fellowship along with design preparations for fabrication to be performed by an ASIC manufacturer.

  1. Prioritizing critical success factors for reverse logistics implementation using fuzzy-TOPSIS methodology

    NASA Astrophysics Data System (ADS)

    Agrawal, Saurabh; Singh, Rajesh K.; Murtaza, Qasim

    2016-03-01

    Electronics industry is one of the fastest growing industries in the world. In India also, there are high turnovers and growing demand of electronics product especially after post liberalization in early nineties. These products generate e-waste which has become big environmental issue. Industries can handle these e-waste and product returns efficiently by developing reverse logistics (RL) system. A thorough study of critical success factors (CSFs) and their ordered implementation is essential for successful RL implementation. The aim of the study is to review the CSFs, and to prioritize them for RL implementation in Indian electronics industry. Twelve CSFs were identified through literature review, and discussion with the experts from the Indian electronics industry. Fuzzy-Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) approach is proposed for prioritizing these CSFs. Perusal of literature indicates that fuzzy-TOPSIS has not been applied earlier for prioritization of CSFs in Indian electronics industry. Five Indian electronics companies were selected for evaluation of this methodology. Results indicate that most of the identified factors are crucial for the RL implementation. Top management awareness, resource management, economic factors, and contracts terms and conditions are top four prioritized factor, and process capabilities and skilled workers is the least prioritized factor. The findings will be useful for successful RL implementation in Indian electronics industry.

  2. Are electronic health records ready for genomic medicine?

    PubMed

    Scheuner, Maren T; de Vries, Han; Kim, Benjamin; Meili, Robin C; Olmstead, Sarah H; Teleki, Stephanie

    2009-07-01

    The goal of this project was to assess genetic/genomic content in electronic health records. Semistructured interviews were conducted with key informants. Questions addressed documentation, organization, display, decision support and security of family history and genetic test information, and challenges and opportunities relating to integrating genetic/genomics content in electronic health records. There were 56 participants: 10 electronic health record specialists, 18 primary care clinicians, 16 medical geneticists, and 12 genetic counselors. Few clinicians felt their electronic record met their current genetic/genomic medicine needs. Barriers to integration were mostly related to problems with family history data collection, documentation, and organization. Lack of demand for genetics content and privacy concerns were also mentioned as challenges. Data elements and functionality requirements that clinicians see include: pedigree drawing; clinical decision support for familial risk assessment and genetic testing indications; a patient portal for patient-entered data; and standards for data elements, terminology, structure, interoperability, and clinical decision support rules. Although most said that there is little impact of genetics/genomics on electronic records today, many stated genetics/genomics would be a driver of content in the next 5-10 years. Electronic health records have the potential to enable clinical integration of genetic/genomic medicine and improve delivery of personalized health care; however, structured and standardized data elements and functionality requirements are needed.

  3. Manufacturing of Liquid-Embedded Elastomers for Stretchable Electronics

    NASA Astrophysics Data System (ADS)

    Kramer, Rebecca; Majidi, Carmel; Weaver, James; Wood, Robert

    2013-03-01

    Future generations of robots, electronics, and assistive medical devices will include systems that are soft, elastically deformable, and may adapt their functionality in unstructured environments. This will require soft active materials for power circuits and sensing of deformation and contact pressure. As the demand for increased elasticity of electrical components heightens, the challenges for functionality revert to basic questions of fabrication, materials, and design. Several designs for soft sensory skins (including strain, pressure and curvature sensors) based on a liquid-embedded-elastomer approach have been developed. This talk will highlight new ``soft MEMS'' manufacturing techniques based on wetting behavior between gallium-indium alloys and elastomers with varying microtextured surface topography. Supported by Harvard MRSEC and the Wyss Institute

  4. Multi-bit dark state memory: Double quantum dot as an electronic quantum memory

    NASA Astrophysics Data System (ADS)

    Aharon, Eran; Pozner, Roni; Lifshitz, Efrat; Peskin, Uri

    2016-12-01

    Quantum dot clusters enable the creation of dark states which preserve electrons or holes in a coherent superposition of dot states for a long time. Various quantum logic devices can be envisioned to arise from the possibility of storing such trapped particles for future release on demand. In this work, we consider a double quantum dot memory device, which enables the preservation of a coherent state to be released as multiple classical bits. Our unique device architecture uses an external gating for storing (writing) the coherent state and for retrieving (reading) the classical bits, in addition to exploiting an internal gating effect for the preservation of the coherent state.

  5. Factors influencing equipment selection in electron beam processing

    NASA Astrophysics Data System (ADS)

    Barnard, J. W.

    2003-08-01

    During the eighties and nineties accelerator manufacturers dramatically increased the beam power available for high-energy equipment. This effort was directed primarily at meeting the demands of the sterilization industry. During this era, the perception that bigger (higher power, higher energy) was always better prevailed since the operating and capital costs of accelerators did not increase with power and energy as fast as the throughput. High power was needed to maintain per unit costs low for treatment. This philosophy runs counter to certain present-day realities of the sterilization business as well as conditions influencing accelerator selection in other electron beam applications. Recent experience in machine selection is described and factors affecting choice are presented.

  6. Control of the π plasmon in a single layer graphene by charge doping

    NASA Astrophysics Data System (ADS)

    Shin, S. Y.; Kim, N. D.; Kim, J. G.; Kim, K. S.; Noh, D. Y.; Kim, Kwang S.; Chung, J. W.

    2011-08-01

    We report that the behavior of a low-energy π plasmon excitation in a single layer graphene (SLG) can be modified by doping external potassium (K) atoms, a feature demanded to realize the graphene plasmonics. Using high-resolution electron-energy-loss spectroscopy, we find that upon K-doping the π plasmon energy increases by 1.1 eV due to the K-induced electron density up to n = 7 × 1013 cm-2 in SLG. The four modified dispersions for different K-dopings, however, are found to merge into a single universal curve when plotted in the dimensionless coordinates indicating that the unique plasmonic character of SLG is preserved despite the K-dopings.

  7. Apparel for Cleaner Clean Rooms

    NASA Technical Reports Server (NTRS)

    1983-01-01

    In the 1960s NASA pioneered contamination control technology, providing a base from which aerospace contractors could develop control measures. NASA conducted special courses for clean room technicians and supervisors, and published a series of handbooks with input from various NASA field centers. These handbooks extended aerospace experience to the medical, pharmaceutical, electronics, and other industries where extreme cleanliness is important. American Hospital Supply Company (AHSC) felt that high technology products with increasingly stringent operating requirements in aerospace, electronics, pharmaceuticals and medical equipment manufacturing demanded improvement in contamination control techniques. After studying the NASA handbooks and visiting NASA facilities, the wealth of information gathered resulted in Micro-clean non-woven garments and testing equipment and procedures for evaluating effectiveness.

  8. Using the NASA Task Load Index to Assess Workload in Electronic Medical Records.

    PubMed

    Hudson, Darren; Kushniruk, Andre W; Borycki, Elizabeth M

    2015-01-01

    Electronic medical records (EMRs) has been expected to decrease health professional workload. The NASA Task Load Index has become an important tool for assessing workload in many domains. However, its application in assessing the impact of an EMR on nurse's workload has remained to be explored. In this paper we report the results of a study of workload and we explore the utility of applying the NASA Task Load Index to assess impact of an EMR at the end of its lifecycle on nurses' workload. It was found that mental and temporal demands were the most responsible for the workload. Further work along these lines is recommended.

  9. Electron beam processing of fresh produce - A critical review

    NASA Astrophysics Data System (ADS)

    Pillai, Suresh D.; Shayanfar, Shima

    2018-02-01

    To meet the increasing global demand for fresh produce, robust processing methods that ensures both the safety and quality of fresh produce are needed. Since fresh produce cannot withstand thermal processing conditions, most of common safety interventions used in other foods are ineffective. Electron beam (eBeam) is a non-thermal technology that can be used to extend the shelf life and ensure the microbiological safety of fresh produce. There have been studies documenting the application of eBeam to ensure both safety and quality in fresh produce, however, there are still unexplored areas that still need further research. This is a critical review on the current literature on the application of eBeam technology for fresh produce.

  10. Post-assembly Modification of Tetrazine-Edged Fe(II)4L6 Tetrahedra.

    PubMed

    Roberts, Derrick A; Pilgrim, Ben S; Cooper, Jonathan D; Ronson, Tanya K; Zarra, Salvatore; Nitschke, Jonathan R

    2015-08-19

    Post-assembly modification (PAM) is a powerful tool for the modular functionalization of self-assembled structures. We report a new family of tetrazine-edged Fe(II)4L6 tetrahedral cages, prepared using different aniline subcomponents, which undergo rapid and efficient PAM by inverse electron-demand Diels-Alder (IEDDA) reactions. Remarkably, the electron-donating or -withdrawing ability of the para-substituent on the aniline moiety influences the IEDDA reactivity of the tetrazine ring 11 bonds away. This effect manifests as a linear free energy relationship, quantified using the Hammett equation, between σ(para) and the rate of the IEDDA reaction. The rate of PAM can thus be adjusted by varying the aniline subcomponent.

  11. Development of low-cost high-performance multispectral camera system at Banpil

    NASA Astrophysics Data System (ADS)

    Oduor, Patrick; Mizuno, Genki; Olah, Robert; Dutta, Achyut K.

    2014-05-01

    Banpil Photonics (Banpil) has developed a low-cost high-performance multispectral camera system for Visible to Short- Wave Infrared (VIS-SWIR) imaging for the most demanding high-sensitivity and high-speed military, commercial and industrial applications. The 640x512 pixel InGaAs uncooled camera system is designed to provide a compact, smallform factor to within a cubic inch, high sensitivity needing less than 100 electrons, high dynamic range exceeding 190 dB, high-frame rates greater than 1000 frames per second (FPS) at full resolution, and low power consumption below 1W. This is practically all the feature benefits highly desirable in military imaging applications to expand deployment to every warfighter, while also maintaining a low-cost structure demanded for scaling into commercial markets. This paper describes Banpil's development of the camera system including the features of the image sensor with an innovation integrating advanced digital electronics functionality, which has made the confluence of high-performance capabilities on the same imaging platform practical at low cost. It discusses the strategies employed including innovations of the key components (e.g. focal plane array (FPA) and Read-Out Integrated Circuitry (ROIC)) within our control while maintaining a fabless model, and strategic collaboration with partners to attain additional cost reductions on optics, electronics, and packaging. We highlight the challenges and potential opportunities for further cost reductions to achieve a goal of a sub-$1000 uncooled high-performance camera system. Finally, a brief overview of emerging military, commercial and industrial applications that will benefit from this high performance imaging system and their forecast cost structure is presented.

  12. Dynamic modulation of electronic properties of graphene by localized carbon doping using focused electron beam induced deposition

    NASA Astrophysics Data System (ADS)

    Kim, S.; Russell, M.; Henry, M.; Kim, S. S.; Naik, R. R.; Voevodin, A. A.; Jang, S. S.; Tsukruk, V. V.; Fedorov, A. G.

    2015-09-01

    We report on the first demonstration of controllable carbon doping of graphene to engineer local electronic properties of a graphene conduction channel using focused electron beam induced deposition (FEBID). Electrical measurements indicate that an ``n-p-n'' junction on graphene conduction channel is formed by partial carbon deposition near the source and drain metal contacts by low energy (<50 eV) secondary electrons due to inelastic collisions of long range backscattered primary electrons generated from a low dose of high energy (25 keV) electron beam (1 × 1018 e- per cm2). Detailed AFM imaging provides direct evidence of the new mechanism responsible for dynamic evolution of the locally varying graphene doping. The FEBID carbon atoms, which are physisorbed and weakly bound to graphene, diffuse towards the middle of graphene conduction channel due to their surface chemical potential gradient, resulting in negative shift of Dirac voltage. Increasing a primary electron dose to 1 × 1019 e- per cm2 results in a significant increase of carbon deposition, such that it covers the entire graphene conduction channel at high surface density, leading to n-doping of graphene channel. Collectively, these findings establish a unique capability of FEBID technique to dynamically modulate the doping state of graphene, thus enabling a new route to resist-free, ``direct-write'' functional patterning of graphene-based electronic devices with potential for on-demand re-configurability.We report on the first demonstration of controllable carbon doping of graphene to engineer local electronic properties of a graphene conduction channel using focused electron beam induced deposition (FEBID). Electrical measurements indicate that an ``n-p-n'' junction on graphene conduction channel is formed by partial carbon deposition near the source and drain metal contacts by low energy (<50 eV) secondary electrons due to inelastic collisions of long range backscattered primary electrons generated from a low dose of high energy (25 keV) electron beam (1 × 1018 e- per cm2). Detailed AFM imaging provides direct evidence of the new mechanism responsible for dynamic evolution of the locally varying graphene doping. The FEBID carbon atoms, which are physisorbed and weakly bound to graphene, diffuse towards the middle of graphene conduction channel due to their surface chemical potential gradient, resulting in negative shift of Dirac voltage. Increasing a primary electron dose to 1 × 1019 e- per cm2 results in a significant increase of carbon deposition, such that it covers the entire graphene conduction channel at high surface density, leading to n-doping of graphene channel. Collectively, these findings establish a unique capability of FEBID technique to dynamically modulate the doping state of graphene, thus enabling a new route to resist-free, ``direct-write'' functional patterning of graphene-based electronic devices with potential for on-demand re-configurability. Electronic supplementary information (ESI) available: Optimization of a PMMA-mediated wet transfer method of graphene, transfer characteristics of all the channels, raw data of drain-source current measured by sweeping a backgate voltage and an AFM topography image and cross-sectional profiles of Fig. 4 and the corresponding electrical measurement along with an estimation of carbon diffusion coefficient. See DOI: 10.1039/c5nr04063a

  13. Polyimide-Epoxy Composites with Superior Bendable Properties for Application in Flexible Electronics

    NASA Astrophysics Data System (ADS)

    Lee, Sangyoup; Yoo, Taewon; Han, Youngyu; Kim, Hanglim; Han, Haksoo

    2017-08-01

    The need for flexible electronics with outstanding bending properties is increasing due to the demand for wearable devices and next-generation flexible or rollable smartphones. In addition, the requirements for flexible or rigid-flexible electronics are sharply increasing to achieve the design of space-saving electronic devices. In this regard, coverlay (CL) film is a key material used in the bending area of flexible electronics, albeit infrequently. Because flexible electronics undergo folding and unfolding numerous times, CL films with superior mechanical and bending properties are required so that the bending area can endure such severe stress. However, because current CL films are only used for a designated bending area in the flexible electronics panel, their highly complicated and expensive manufacturing procedure is a disadvantage. In addition, the thickness of CL films must be decreased to satisfy the ongoing requirement for increasingly thin products. However, due to the limitations of the two-layer structure of existing CL films, the manufacturing process cannot be made more cost effective by simply applying more thin film onto the board. To address this problem, we have developed liquid coverlay inks (LCIs) with superior bendable properties, in comparison with CL films, when applied onto flexible electronics using a screen-printing method. The results show that LCIs have the potential to become one of the leading candidates to replace existing CL films because of their lower cost and faster manufacturing process.

  14. A Generalized Electron Heat Flow Relation and its Connection to the Thermal Force and the Solar Wind Parallel Electric Field

    NASA Astrophysics Data System (ADS)

    Scudder, J. D.

    2017-12-01

    Enroute to a new formulation of the heat law for the solar wind plasma the role of the invariably neglected, but omnipresent, thermal force for the multi-fluid physics of the corona and solar wind expansion will be discussed. This force (a) controls the size of the collisional ion electron energy exchange, favoring the thermal vs supra thermal electrons; (b) occurs whenever heat flux occurs; (c) remains after the electron and ion fluids come to a no slip, zero parallel current, equilibrium; (d) enhances the equilibrium parallel electric field; but (e) has a size that is theoretically independent of the electron collision frequency - allowing its importance to persist far up into the corona where collisions are invariably ignored in first approximation. The constituent parts of the thermal force allow the derivation of a new generalized electron heat flow relation that will be presented. It depends on the separate field aligned divergences of electron and ion pressures and the gradients of the ion gravitational potential and parallel flow energies and is based upon a multi-component electron distribution function. The new terms in this heat law explicitly incorporate the astrophysical context of gradients, acceleration and external forces that make demands on the parallel electric field and quasi-neutrality; essentially all of these effects are missing in traditional formulations.

  15. Microtechnology management considering test and cost aspects for stacked 3D ICs with MEMS

    NASA Astrophysics Data System (ADS)

    Hahn, K.; Wahl, M.; Busch, R.; Grünewald, A.; Brück, R.

    2018-01-01

    Innovative automotive systems require complex semiconductor devices currently only available in consumer grade quality. The European project TRACE will develop and demonstrate methods, processes, and tools to facilitate usage of Consumer Electronics (CE) components to be deployable more rapidly in the life-critical automotive domain. Consumer electronics increasingly use heterogeneous system integration methods and "More than Moore" technologies, which are capable to combine different circuit domains (Analog, Digital, RF, MEMS) and which are integrated within SiP or 3D stacks. Making these technologies or at least some of the process steps available under automotive electronics requirements is an important goal to keep pace with the growing demand for information processing within cars. The approach presented in this paper aims at a technology management and recommendation system that covers technology data, functional and non-functional constraints, and application scenarios, and that will comprehend test planning and cost consideration capabilities.

  16. Quantum-circuit refrigerator

    NASA Astrophysics Data System (ADS)

    Tan, Kuan Yen; Partanen, Matti; Lake, Russell E.; Govenius, Joonas; Masuda, Shumpei; Möttönen, Mikko

    2017-05-01

    Quantum technology promises revolutionizing applications in information processing, communications, sensing and modelling. However, efficient on-demand cooling of the functional quantum degrees of freedom remains challenging in many solid-state implementations, such as superconducting circuits. Here we demonstrate direct cooling of a superconducting resonator mode using voltage-controllable electron tunnelling in a nanoscale refrigerator. This result is revealed by a decreased electron temperature at a resonator-coupled probe resistor, even for an elevated electron temperature at the refrigerator. Our conclusions are verified by control experiments and by a good quantitative agreement between theory and experimental observations at various operation voltages and bath temperatures. In the future, we aim to remove spurious dissipation introduced by our refrigerator and to decrease the operational temperature. Such an ideal quantum-circuit refrigerator has potential applications in the initialization of quantum electric devices. In the superconducting quantum computer, for example, fast and accurate reset of the quantum memory is needed.

  17. A Flexible Electronic Commerce Recommendation System

    NASA Astrophysics Data System (ADS)

    Gong, Songjie

    Recommendation systems have become very popular in E-commerce websites. Many of the largest commerce websites are already using recommender technologies to help their customers find products to purchase. An electronic commerce recommendation system learns from a customer and recommends products that the customer will find most valuable from among the available products. But most recommendation methods are hard-wired into the system and they support only fixed recommendations. This paper presented a framework of flexible electronic commerce recommendation system. The framework is composed by user model interface, recommendation engine, recommendation strategy model, recommendation technology group, user interest model and database interface. In the recommender strategy model, the method can be collaborative filtering, content-based filtering, mining associate rules method, knowledge-based filtering method or the mixed method. The system mapped the implementation and demand through strategy model, and the whole system would be design as standard parts to adapt to the change of the recommendation strategy.

  18. Nonvolatile memory behavior of nanocrystalline cellulose/graphene oxide composite films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Valentini, L., E-mail: luca.valentini@unipg.it; Cardinali, M.; Fortunati, E.

    2014-10-13

    With the continuous advance of modern electronics, the demand for nonvolatile memory cells rapidly grows. In order to develop post-silicon electronic devices, it is necessary to find innovative solutions to the eco-sustainability problem of materials for nonvolatile memory cells. In this work, we realized a resistive memory device based on graphene oxide (GO) and GO/cellulose nanocrystals (CNC) thin films. Aqueous solutions of GO and GO with CNC have been prepared and drop cast between two metal electrodes. Such thin-film based devices showed a transition between low and high conductivity states upon the forward and backward sweeping of an external electricmore » field. This reversible current density transition behavior demonstrates a typical memory characteristic. The obtained results open an easy route for electronic information storage based on the integration of nanocrystalline cellulose onto graphene based devices.« less

  19. Control Structures for VSC-based FACTS Devices under Normal and Faulted AC-systems

    NASA Astrophysics Data System (ADS)

    Babaei, Saman

    This thesis is concerned with improving the Flexible AC Transmission Systems (FACTS) devices performance under the normal and fault AC-system conditions by proposing new control structures and also converter topologies. The combination of the increasing electricity demand and restrictions in expanding the power system infrastructures has urged the utility owners to deploy the utility-scaled power electronics in the power system. Basically, FACTS is referred to the application of the power electronics in the power systems. Voltage Source Converter (VSC) is the preferred building block of the FACTS devices and many other utility-scale power electronics applications. Despite of advances in the semiconductor technology and ultra-fast microprocessor based controllers, there are still many issues to address and room to improve[25]. An attempt is made in this thesis to address these important issues of the VSC-based FACTS devices and provide solutions to improve them.

  20. A double layer model for solar X-ray and microwave pulsations

    NASA Technical Reports Server (NTRS)

    Tapping, K. F.

    1986-01-01

    The wide range of wavelengths over which quasi-periodic pulsations have been observed suggests that the mechanism causing them acts upon the supply of high energy electrons driving the emission processes. A model is described which is based upon the radial shrinkage of a magnetic flux tube. The concentration of the current, along with the reduction in the number of available charge carriers, can rise to a condition where the current demand exceeds the capacity of the thermal electrons. Driven by the large inductance of the external current circuit, an instability takes place in the tube throat, resulting in the formation of a potential double layer, which then accelerates electrons and ions to MeV energies. The double layer can be unstable, collapsing and reforming repeatedly. The resulting pulsed particle beams give rise to pulsating emission which are observed at radio and X-ray wavelengths.

  1. Progress Towards High-Sensitivity Arrays of Detectors of Sub-mm Radiation Using Superconducting Tunnel Junctions with Integrated Radio Frequency Single-Electron Transistors

    NASA Technical Reports Server (NTRS)

    Stevenson, T. R.; Hsieh, W.-T.; Li, M. J.; Prober, D. E.; Rhee, K. W.; Schoelkopf, R. J.; Stahle, C. M.; Teufel, J.; Wollack, E. J.

    2004-01-01

    For high resolution imaging and spectroscopy in the FIR and submillimeter, space observatories will demand sensitive, fast, compact, low-power detector arrays with 104 pixels and sensitivity less than 10(exp -20) W/Hz(sup 0.5). Antenna-coupled superconducting tunnel junctions with integrated rf single-electron transistor readout amplifiers have the potential for achieving this high level of sensitivity, and can take advantage of an rf multiplexing technique. The device consists of an antenna to couple radiation into a small superconducting volume and cause quasiparticle excitations, and a single-electron transistor to measure current through junctions contacting the absorber. We describe optimization of device parameters, and results on fabrication techniques for producing devices with high yield for detector arrays. We also present modeling of expected saturation power levels, antenna coupling, and rf multiplexing schemes.

  2. Gate-controlled electromechanical backaction induced by a quantum dot

    NASA Astrophysics Data System (ADS)

    Okazaki, Yuma; Mahboob, Imran; Onomitsu, Koji; Sasaki, Satoshi; Yamaguchi, Hiroshi

    2016-04-01

    Semiconductor-based quantum structures integrated into mechanical resonators have emerged as a unique platform for generating entanglement between macroscopic phononic and mesocopic electronic degrees of freedom. A key challenge to realizing this is the ability to create and control the coupling between two vastly dissimilar systems. Here, such coupling is demonstrated in a hybrid device composed of a gate-defined quantum dot integrated into a piezoelectricity-based mechanical resonator enabling milli-Kelvin phonon states to be detected via charge fluctuations in the quantum dot. Conversely, the single electron transport in the quantum dot can induce a backaction onto the mechanics where appropriate bias of the quantum dot can enable damping and even current-driven amplification of the mechanical motion. Such electron transport induced control of the mechanical resonator dynamics paves the way towards a new class of hybrid semiconductor devices including a current injected phonon laser and an on-demand single phonon emitter.

  3. Sub-micron resolution rf cavity beam position monitor system at the SACLA XFEL facility

    NASA Astrophysics Data System (ADS)

    Maesaka, H.; Ego, H.; Inoue, S.; Matsubara, S.; Ohshima, T.; Shintake, T.; Otake, Y.

    2012-12-01

    We have developed and constructed a C-band (4.760 GHz) rf cavity beam position monitor (RF-BPM) system for the XFEL facility at SPring-8, SACLA. The demanded position resolution of the RF-BPM is less than 1 μm, because an electron beam and x-rays must be overlapped within 4 μm precision in the undulator section for sufficient FEL interaction between the electrons and x-rays. In total, 57 RF-BPMs, including IQ demodulators and high-speed waveform digitizers for signal processing, were produced and installed into SACLA. We evaluated the position resolutions of 20 RF-BPMs in the undulator section by using a 7 GeV electron beam having a 0.1 nC bunch charge. The position resolution was measured to be less than 0.6 μm, which was sufficient for the XFEL lasing in the wavelength region of 0.1 nm, or shorter.

  4. Assessment of Electronic Government Information Products

    DTIC Science & Technology

    1999-03-30

    Center for Environmental Info. & Statistics CM Consumer Handbook for Reducing Solid Waste CM Envirofacts Warehouse CM EPA Online Library System (OLS) CP...Hazardous Waste Site Query (CERCLIS Data) CM Surf Your Watershed CM Test Methods for Evaluating Solid Waste : Physical/Chemical Methods (SW-846) CM...SGML because they consider it "intelligent data" that can automatically generate other formats (e.g., web, BBS, Fax on Demand) through templates and

  5. Some aspects of applying nanostructured materials in air filtration, water filtration and electrical engineering

    NASA Astrophysics Data System (ADS)

    Kimmer, Dusan; Vincent, Ivo; Lovecka, Lenka; Kazda, Tomas; Giurg, Adam; Skorvan, Ondrej

    2017-05-01

    Nanostructures prepared from nanofibres and nanostructured composites prepared from nanofibres and fillers are gradually becoming increasingly demanded materials for applications in various industrial branches connected with catalysis, environment protection (air filtration, waste water treatment, sound absorption), in biological engineering, electronics (battery separators, electrode materials), etc. Selected applications of these materials prepared in the company SPUR a.s. are summed up in the following presentation.

  6. LMS and New Media

    DTIC Science & Technology

    2009-08-19

    Management of Social Media The Caring Personal Agent SUSAN BULL1, JIM GREER2, GORD MCCALLA2 1 Educational Technology Research Group, Electronic...Discussion Forums, Leader Education , On Demand Learning . 24 Cianciolo, A. (2008) Study Report 2008-05. Program Evaluation for U.S. Army Lifelong...AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Advanced Decision Learning (ADL

  7. Development and Applications of Portable Biosensors.

    PubMed

    Srinivasan, Balaji; Tung, Steve

    2015-08-01

    The significance of microfluidics-based and microelectromechanical systems-based biosensors has been widely acknowledged, and many reviews have explored their potential applications in clinical diagnostics, personalized medicine, global health, drug discovery, food safety, and forensics. Because health care costs are increasing, there is an increasing need to remotely monitor the health condition of patients by point-of-care-testing. The demand for biosensors for detection of biological warfare agents has increased, and research is focused on ways of producing small portable devices that would allow fast, accurate, and on-site detection. In the past decade, the demand for rapid and accurate on-site detection of plant disease diagnosis has increased due to emerging pathogens with resistance to pesticides, increased human mobility, and regulations limiting the application of toxic chemicals to prevent spread of diseases. The portability of biosensors for on-site diagnosis is limited due to various issues, including sample preparation techniques, fluid-handling techniques, the limited lifetime of biological reagents, device packaging, integrating electronics for data collection/analysis, and the requirement of external accessories and power. Many microfluidic, electronic, and biological design strategies, such as handling liquids in biosensors without pumps/valves, the application of droplet-based microfluidics, paper-based microfluidic devices, and wireless networking capabilities for data transmission, are being explored. © 2015 Society for Laboratory Automation and Screening.

  8. Spectroscopic detection and analysis of atomic emissions during industrial pulsed laser-drilling of structural aerospace alloys

    NASA Astrophysics Data System (ADS)

    Bright, Robin Michael

    The ability to adequately cool internal gas-turbine engine components in next-generation commercial and military aircraft is of extreme importance to the aerospace industry as the demand for high-efficiency engines continues to push operating temperatures higher. Pulsed laser-drilling is rapidly becoming the preferred method of creating cooling holes in high temperature components due a variety of manufacturing advantages of laser-drilling over conventional hole-drilling techniques. As cooling requirements become more demanding, the impact of drilling conditions on material removal behavior and subsequent effects on hole quality becomes critical. In this work, the development of emission spectroscopy as a method to probe the laser-drilling process is presented and subsequently applied to the study of material behavior of various structural aerospace materials during drilling. Specifically, emitted photons associated with energy level transitions within excited neutral atoms in material ejected during drilling were detected and analyzed. Systematic spectroscopic studies indicated that electron energy level populations and calculated electron temperatures within ejected material are dependent on both laser pulse energy and duration. Local thermal conditions detected by the developed method were related to the characteristics of ejected material during drilling and to final hole quality. Finally, methods of utilizing the observed relationships for spectroscopic process monitoring and control were demonstrated.

  9. Precision glass molding of high-resolution diffractive optical elements

    NASA Astrophysics Data System (ADS)

    Prater, Karin; Dukwen, Julia; Scharf, Toralf; Herzig, Hans P.; Plöger, Sven; Hermerschmidt, Andreas

    2016-04-01

    The demand of high resolution diffractive optical elements (DOE) is growing. Smaller critical dimensions allow higher deflection angles and can fulfill more demanding requirements, which can only be met by using electron-beam lithography. Replication techniques are more economical, since the high cost of the master can be distributed among a larger number of replicas. The lack of a suitable mold material for precision glass molding has so far prevented an industrial use. Glassy Carbon (GC) offers a high mechanical strength and high thermal strength. No anti-adhesion coatings are required in molding processes. This is clearly an advantage for high resolution, high aspect ratio microstructures, where a coating with a thickness between 10 nm and 200 nm would cause a noticeable rounding of the features. Electron-beam lithography was used to fabricate GC molds with highest precision and feature sizes from 250 nm to 2 μm. The master stamps were used for precision glass molding of a low Tg glass L-BAL42 from OHARA. The profile of the replicated glass is compared to the mold with the help of SEM images. This allows discussion of the max. aspect-ratio and min. feature size. To characterize optical performances, beamsplitting elements are fabricated and their characteristics were investigated, which are in excellent agreement to theory.

  10. Optimizing low-light microscopy with back-illuminated electron multiplying charge-coupled device: enhanced sensitivity, speed, and resolution.

    PubMed

    Coates, Colin G; Denvir, Donal J; McHale, Noel G; Thornbury, Keith D; Hollywood, Mark A

    2004-01-01

    The back-illuminated electron multiplying charge-coupled device (EMCCD) camera is having a profound influence on the field of low-light dynamic cellular microscopy, combining highest possible photon collection efficiency with the ability to virtually eliminate the readout noise detection limit. We report here the use of this camera, in 512 x 512 frame-transfer chip format at 10-MHz pixel readout speed, in optimizing a demanding ultra-low-light intracellular calcium flux microscopy setup. The arrangement employed includes a spinning confocal Nipkow disk, which, while facilitating the need to both generate images at very rapid frame rates and minimize background photons, yields very weak signals. The challenge for the camera lies not just in detecting as many of these scarce photons as possible, but also in operating at a frame rate that meets the temporal resolution requirements of many low-light microscopy approaches, a particular demand of smooth muscle calcium flux microscopy. Results presented illustrate both the significant sensitivity improvement offered by this technology over the previous standard in ultra-low-light CCD detection, the GenIII+intensified charge-coupled device (ICCD), and also portray the advanced temporal and spatial resolution capabilities of the EMCCD. Copyright 2004 Society of Photo-Optical Instrumentation Engineers.

  11. Psychophysics of reading. XVII. Low-vision performance with four types of electronically magnified text.

    PubMed

    Harland, S; Legge, G E; Luebker, A

    1998-03-01

    Most people with low vision need magnification to read. Page navigation is the process of moving a magnifier during reading. Modern electronic technology can provide many alternatives for navigating through text. This study compared reading speeds for four methods of displaying text. The four methods varied in their page-navigation demands. The closed-circuit television (CCTV) and MOUSE methods involved manual navigation. The DRIFT method (horizontally drifting text) involved no manual navigation, but did involve both smooth-pursuit and saccadic eye movements. The rapid serial visual presentation (RSVP) method involved no manual navigation, and relatively few eye movements. There were 7 normal subjects and 12 low-vision subjects (7 with central-field loss, CFL group, and 5 with central fields intact, CFI group). The subjects read 70-word passages at speeds that yielded good comprehension. Taking the CCTV reading speed as a benchmark, neither the normal nor low-vision subjects had significantly different speeds with the MOUSE method. As expected from the reduced navigational demands, normal subjects read faster with the DRIFT method (85% faster) and the RSVP method (169%). The CFI group read significantly faster with DRIFT (43%) and RSVP (38%). The CFL group showed no significant differences in reading speed for the four methods.

  12. Onset of action during on-demand treatment with maalox suspension or low-dose ranitidine for heartburn.

    PubMed

    Faaij, R A; Van Gerven, J M; Jolivet-Landreau, I; Masclee, A A; Vendrig, E M; Schoemaker, R C; Jacobs, L D; Cohen, A F

    1999-12-01

    To compare the onset of action of the local antacid Maalox and the systemic H2-antagonist ranitidine, during 'on demand' ambulant treatment of a single heartburn episode, using a randomized, parallel group, double-blind, double-dummy design. Subjects with self-perceived heartburn without known gastrointestinal disease or interfering treatments were selected with questionnaires. The study was performed unsupervised, whenever heartburn required medication. An electronic patient diary gave instructions when to take study medication, and provided visual analogue scales and five-item relief ratings for heartburn, at frequent time intervals activated by an alarm-clock. After a study of the natural history of heartburn and the feasibility of the study procedures in 23 patients, 49 subjects took Maalox and 45 ranitidine. Half of these experienced meaningful heartburn relief within 19 min after Maalox, and within 70 min after ranitidine. One hour after intake, the average heartburn relief score was 3.43 in the Maalox group and 3.04 in the ranitidine group (3 means 'slight improvement' and 4 'strong improvement'). Heartburn was similar in both groups after 3 h. Maalox provides faster relief of heartburn than ranitidine. Heartburn can be assessed frequently and reliably under ambulant conditions using an electronic patient diary.

  13. Carbon nanotube-copper exhibiting metal-like thermal conductivity and silicon-like thermal expansion for efficient cooling of electronics.

    PubMed

    Subramaniam, Chandramouli; Yasuda, Yuzuri; Takeya, Satoshi; Ata, Seisuke; Nishizawa, Ayumi; Futaba, Don; Yamada, Takeo; Hata, Kenji

    2014-03-07

    Increasing functional complexity and dimensional compactness of electronic devices have led to progressively higher power dissipation, mainly in the form of heat. Overheating of semiconductor-based electronics has been the primary reason for their failure. Such failures originate at the interface of the heat sink (commonly Cu and Al) and the substrate (silicon) due to the large mismatch in thermal expansion coefficients (∼300%) of metals and silicon. Therefore, the effective cooling of such electronics demands a material with both high thermal conductivity and a similar coefficient of thermal expansion (CTE) to silicon. Addressing this demand, we have developed a carbon nanotube-copper (CNT-Cu) composite with high metallic thermal conductivity (395 W m(-1) K(-1)) and a low, silicon-like CTE (5.0 ppm K(-1)). The thermal conductivity was identical to that of Cu (400 W m(-1) K(-1)) and higher than those of most metals (Ti, Al, Au). Importantly, the CTE mismatch between CNT-Cu and silicon was only ∼10%, meaning an excellent compatibility. The seamless integration of CNTs and Cu was achieved through a unique two-stage electrodeposition approach to create an extensive and continuous interface between the Cu and CNTs. This allowed for thermal contributions from both Cu and CNTs, resulting in high thermal conductivity. Simultaneously, the high volume fraction of CNTs balanced the thermal expansion of Cu, accounting for the low CTE of the CNT-Cu composite. The experimental observations were in good quantitative concurrence with the theoretically described 'matrix-bubble' model. Further, we demonstrated identical in-situ thermal strain behaviour of the CNT-Cu composite to Si-based dielectrics, thereby generating the least interfacial thermal strain. This unique combination of properties places CNT-Cu as an isolated spot in an Ashby map of thermal conductivity and CTE. Finally, the CNT-Cu composite exhibited the greatest stability to temperature as indicated by its low thermal distortion parameter (TDP). Thus, this material presents a viable and efficient alternative to existing materials for thermal management in electronics.

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ledbetter, Rhesa N.; Garcia Costas, Amaya M.; Lubner, Carolyn E.

    The biological reduction of dinitrogen (N 2) to ammonia (NH 3) by nitrogenase is an energetically demanding reaction that requires low-potential electrons and ATP; however, pathways used to deliver the electrons from central metabolism to the reductants of nitrogenase, ferredoxin or flavodoxin, remain unknown for many diazotrophic microbes. The FixABCX protein complex has been proposed to reduce flavodoxin or ferredoxin using NADH as the electron donor in a process known as electron bifurcation. Herein, the FixABCX complex from Azotobacter vinelandii was purified and demonstrated to catalyze an electron bifurcation reaction: oxidation of NADH (E m = -320 mV) coupled tomore » reduction of flavodoxin semiquinone (E m = -460 mV) and reduction of coenzyme Q (E m = 10 mV). Knocking out fix genes rendered ..delta..rnf A. vinelandii cells unable to fix dinitrogen, confirming that the FixABCX system provides another route for delivery of electrons to nitrogenase. Characterization of the purified FixABCX complex revealed the presence of flavin and iron-sulfur cofactors confirmed by native mass spectrometry, electron paramagnetic resonance spectroscopy, and transient absorption spectroscopy. Transient absorption spectroscopy further established the presence of a short-lived flavin semiquinone radical, suggesting that a thermodynamically unstable flavin semiquinone may participate as an intermediate in the transfer of an electron to flavodoxin. A structural model of FixABCX, generated using chemical cross-linking in conjunction with homology modeling, revealed plausible electron transfer pathways to both high- and low-potential acceptors. Altogether, this study informs a mechanism for electron bifurcation, offering insight into a unique method for delivery of low-potential electrons required for energy-intensive biochemical conversions.« less

  15. Designing Crane Controls with Applied Mechanical and Electrical Safety Features

    NASA Technical Reports Server (NTRS)

    Lytle, Bradford P.; Walczak, Thomas A.

    2002-01-01

    The use of overhead traveling bridge cranes in many varied applications is common practice. In particular, the use of cranes in the nuclear, military, commercial, aerospace, and other industries can involve safety critical situations. Considerations for Human Injury or Casualty, Loss of Assets, Endangering the Environment, or Economic Reduction must be addressed. Traditionally, in order to achieve additional safety in these applications, mechanical systems have been augmented with a variety of devices. These devices assure that a mechanical component failure shall reduce the risk of a catastrophic loss of the correct and/or safe load carrying capability. ASME NOG-1-1998, (Rules for Construction of Overhead and Gantry Cranes, Top Running Bridge, and Multiple Girder), provides design standards for cranes in safety critical areas. Over and above the minimum safety requirements of todays design standards, users struggle with obtaining a higher degree of reliability through more precise functional specifications while attempting to provide "smart" safety systems. Electrical control systems also may be equipped with protective devices similar to the mechanical design features. Demands for improvement of the cranes "control system" is often recognized, but difficult to quantify for this traditionally "mechanically" oriented market. Finite details for each operation must be examined and understood. As an example, load drift (or small motions) at close tolerances can be unacceptable (and considered critical). To meet these high functional demands encoders and other devices are independently added to control systems to provide motion and velocity feedback to the control drive. This paper will examine the implementation of Programmable Electronic Systems (PES). PES is a term this paper will use to describe any control system utilizing any programmable electronic device such as Programmable Logic Controllers (PLC), or an Adjustable Frequency Drive (AID) 'smart' programmable motion controller. Therefore the use of the term Programmable Electronic Systems (PES) is an encompassing description for a large spectrum of programmable electronic control devices.

  16. A combined electrocoagulation-sorption process applied to mixed industrial wastewater.

    PubMed

    Linares-Hernández, Ivonne; Barrera-Díaz, Carlos; Roa-Morales, Gabriela; Bilyeu, Bryan; Ureña-Núñez, Fernando

    2007-06-01

    The removal of organic pollutants from a highly complex industrial wastewater by a aluminium electrocoagulation process coupled with biosorption was evaluated. Under optimal conditions of pH 8 and 45.45 Am(-2) current density, the electrochemical method yields a very effective reduction of all organic pollutants, this reduction was enhanced when the biosorption treatment was applied as a polishing step. Treatment reduced chemical oxygen demand (COD) by 84%, biochemical oxygen demand (BOD(5)) by 78%, color by 97%, turbidity by 98% and fecal coliforms by 99%. The chemical species formed in aqueous solution were determined. The initial and final pollutant levels in the wastewater were monitored using UV-vis spectrometry and cyclic voltammetry. Finally, the morphology and elemental composition of the biosorbent was characterized with scanning electron microscopy (SEM) and energy dispersion spectra (EDS).

  17. Storage Free Smart Energy Management for Frequency Control in a Diesel-PV-Fuel Cell-Based Hybrid AC Microgrid.

    PubMed

    Sekhar, P C; Mishra, S

    2016-08-01

    This paper proposes a novel, smart energy management scheme for a microgrid, consisting of a diesel generator and power electronic converter interfaced renewable energy-based generators, such as photovoltaic (PV) and fuel cell, for frequency regulation without any storage. In the proposed strategy, output of the PV is controlled in coordination with other generators using neurofuzzy controller, either only for transient frequency regulation or for both transient and steady-state frequency regulation, depending on the load demand, thereby eliminating the huge storage requirements. The option of demand response control is also explored along with the generation control. For accurate and quick tracking of maximum power point and its associated reserve power from the PV generator, this paper also proposes a novel adaptive-predictor-corrector-based tracking mechanism.

  18. Upgrade possibilities for continuous wave rf electron guns based on room-temperature very high frequency technology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sannibale, F.; Filippetto, D.; Johnson, M.

    The past decade was characterized by an increasing scientific demand for extending towards higher repetition rates (MHz class and beyond) the performance of already operating lower repetition rate accelerator-based instruments such as x-ray free electron lasers (FELs) and ultrafast electron diffraction (UED) and microscopy (UEM) instruments. Such a need stimulated a worldwide spread of a vibrant R & D activity targeting the development of high-brightness electron sources capable of operating at these challenging rates. Among the different technologies pursued, rf guns based on room-temperature structures resonating in the very high frequency (VHF) range (30-300 MHz) and operating in continuous wavemore » successfully demonstrated in the past few years the targeted brightness and reliability. Nonetheless, recently proposed upgrades for x-ray FELs and the always brightness-frontier applications such as UED and UEM are now requiring a further step forward in terms of beam brightness in electron sources. Here, we present a few possible upgrade paths that would allow one to extend, in a relatively simple and cost-effective way, the performance of the present VHF technology to the required new goals.« less

  19. Upgrade possibilities for continuous wave rf electron guns based on room-temperature very high frequency technology

    DOE PAGES

    Sannibale, F.; Filippetto, D.; Johnson, M.; ...

    2017-11-27

    The past decade was characterized by an increasing scientific demand for extending towards higher repetition rates (MHz class and beyond) the performance of already operating lower repetition rate accelerator-based instruments such as x-ray free electron lasers (FELs) and ultrafast electron diffraction (UED) and microscopy (UEM) instruments. Such a need stimulated a worldwide spread of a vibrant R & D activity targeting the development of high-brightness electron sources capable of operating at these challenging rates. Among the different technologies pursued, rf guns based on room-temperature structures resonating in the very high frequency (VHF) range (30-300 MHz) and operating in continuous wavemore » successfully demonstrated in the past few years the targeted brightness and reliability. Nonetheless, recently proposed upgrades for x-ray FELs and the always brightness-frontier applications such as UED and UEM are now requiring a further step forward in terms of beam brightness in electron sources. Here, we present a few possible upgrade paths that would allow one to extend, in a relatively simple and cost-effective way, the performance of the present VHF technology to the required new goals.« less

  20. Structural and electronic properties of copper-doped chalcogenide glasses

    NASA Astrophysics Data System (ADS)

    Guzman, David M.; Strachan, Alejandro

    2017-10-01

    Using ab initio molecular dynamics based on density functional theory, we study the atomic and electronic structure, and transport properties of copper-doped germanium-based chalcogenide glasses. These mixed ionic-electronic conductor materials exhibit resistance or threshold switching under external electric field depending on slight variations of chemical composition. Understanding the origin of the transport character is essential for the functionalization of glassy chalcogenides for nanoelectronics applications. To this end, we generated atomic structures for GeX3 and GeX6 (X = S, Se, Te) at different copper concentrations and characterized the atomic origin of electronic states responsible for transport and the tendency of copper clustering as a function of metal concentration. Our results show that copper dissolution energies explain the tendency of copper to agglomerate in telluride glasses, consistent with filamentary conduction. In contrast, copper is less prone to cluster in sulfides and selenides leading to hysteresisless threshold switching where the nature of transport is dominated by electronic midgap defects derived from polar chalcogen bonds and copper atoms. Simulated I -V curves show that at least 35% by weight of copper is required to achieve the current demands of threshold-based devices for memory applications.

  1. Differential cross sections for electron-impact excitation of the electronic states of pyrimidine

    NASA Astrophysics Data System (ADS)

    Brunger, Michael; Jones, Darryl; Bellm, Susan

    2012-06-01

    Pyrimidine (C4N2H4) is an important molecule, as it forms the basis of larger biomolecules, such as the DNA bases thymine, cytosine and uracil. There is a pressing demand for low-energy electron scattering data from such biological analogs in order to model radiation induced damage [1]. We therefore present the first measurements for absolute differential cross section data for low-energy electron-impact excitation of the electronic states of pyrimidine. The present measurements were performed using a crossed-beam apparatus [2] for incident electron energies ranging between 15 to 50eV while covering a 10 to 90^o angular range. Here the absolute scale has been determined through a normalisation to the recently measured elastic scattering differential cross section data for pyrimidine [3]. [1] F. Ferreira da Silva, D. Almeida, G. Martins, A. R. Milosavljevic, B. P. Marinkovic, S. V. Hoffmann, N. J. Mason, Y. Nunes, G. Garcia and P. Limao-Vieira, Phys Chem Chem Phys 12, 6717 (2010). [2] M. J. Brunger and P. J. O. Teubner, Phys Rev A 41, 1413 (1990). [3] P. Palihawadana, J. Sullivan, M. Brunger, C. Winstead, V. McKoy, G. Garcia, F. Blanco and S. Buckman, Phys Rev A 84, 062702 (2011).

  2. Simple and cost-effective method of highly conductive and elastic carbon nanotube/polydimethylsiloxane composite for wearable electronics.

    PubMed

    Kim, Jeong Hun; Hwang, Ji-Young; Hwang, Ha Ryeon; Kim, Han Seop; Lee, Joong Hoon; Seo, Jae-Won; Shin, Ueon Sang; Lee, Sang-Hoon

    2018-01-22

    The development of various flexible and stretchable materials has attracted interest for promising applications in biomedical engineering and electronics industries. This interest in wearable electronics, stretchable circuits, and flexible displays has created a demand for stable, easily manufactured, and cheap materials. However, the construction of flexible and elastic electronics, on which commercial electronic components can be mounted through simple and cost-effective processing, remains challenging. We have developed a nanocomposite of carbon nanotubes (CNTs) and polydimethylsiloxane (PDMS) elastomer. To achieve uniform distributions of CNTs within the polymer, an optimized dispersion process was developed using isopropyl alcohol (IPA) and methyl-terminated PDMS in combination with ultrasonication. After vaporizing the IPA, various shapes and sizes can be easily created with the nanocomposite, depending on the mold. The material provides high flexibility, elasticity, and electrical conductivity without requiring a sandwich structure. It is also biocompatible and mechanically stable, as demonstrated by cytotoxicity assays and cyclic strain tests (over 10,000 times). We demonstrate the potential for the healthcare field through strain sensor, flexible electric circuits, and biopotential measurements such as EEG, ECG, and EMG. This simple and cost-effective fabrication method for CNT/PDMS composites provides a promising process and material for various applications of wearable electronics.

  3. Comprehensive process for the recovery of value and critical materials from electronic waste

    DOE PAGES

    Diaz, Luis A.; Lister, Tedd E.; Parkman, Jacob A.; ...

    2016-04-08

    The development of technologies that contribute to the proper disposal and treatment of electronic waste is not just an environmental need, but an opportunity for the recovery and recycle of valuable metals and critical materials. Value elements in electronic waste include gold, palladium, silver, copper, nickel, and rare earth elements (RE). Here, we present the development of a process that enables efficient recycling of metals from scrap mobile electronics. An electro recycling (ER) process, based on the regeneration of Fe 3+ as a weak oxidizer, is studied for the selective recovery of base metals while leaving precious metals for separatemore » extraction at reduced chemical demand. A separate process recovers rare earth oxides from magnets in electronics. Furthermore, recovery and extraction efficiencies ca. 90 % were obtained for the extraction of base metals from the non-ferromagnetic fraction in the two different solution matrices tested (H 2SO 4, and HCl). The effect of the pre-extraction of base metals in the increase of precious metals extraction efficiency was verified. On the other hand, the extraction of rare earths from the ferromagnetic fraction, performed by means of anaerobic extraction in acid media, was assessed for the selective recovery of rare earths. We developed a comprehensive flow sheet to process electronic waste to value products.« less

  4. Managing and Communicating Operational Workflow: Designing and Implementing an Electronic Outpatient Whiteboard.

    PubMed

    Steitz, Bryan D; Weinberg, Stuart T; Danciu, Ioana; Unertl, Kim M

    2016-01-01

    Healthcare team members in emergency department contexts have used electronic whiteboard solutions to help manage operational workflow for many years. Ambulatory clinic settings have highly complex operational workflow, but are still limited in electronic assistance to communicate and coordinate work activities. To describe and discuss the design, implementation, use, and ongoing evolution of a coordination and collaboration tool supporting ambulatory clinic operational workflow at Vanderbilt University Medical Center (VUMC). The outpatient whiteboard tool was initially designed to support healthcare work related to an electronic chemotherapy order-entry application. After a highly successful initial implementation in an oncology context, a high demand emerged across the organization for the outpatient whiteboard implementation. Over the past 10 years, developers have followed an iterative user-centered design process to evolve the tool. The electronic outpatient whiteboard system supports 194 separate whiteboards and is accessed by over 2800 distinct users on a typical day. Clinics can configure their whiteboards to support unique workflow elements. Since initial release, features such as immunization clinical decision support have been integrated into the system, based on requests from end users. The success of the electronic outpatient whiteboard demonstrates the usefulness of an operational workflow tool within the ambulatory clinic setting. Operational workflow tools can play a significant role in supporting coordination, collaboration, and teamwork in ambulatory healthcare settings.

  5. The Electron Bifurcating FixABCX Protein Complex from Azotobacter vinelandii: Generation of Low-Potential Reducing Equivalents for Nitrogenase Catalysis.

    PubMed

    Ledbetter, Rhesa N; Garcia Costas, Amaya M; Lubner, Carolyn E; Mulder, David W; Tokmina-Lukaszewska, Monika; Artz, Jacob H; Patterson, Angela; Magnuson, Timothy S; Jay, Zackary J; Duan, H Diessel; Miller, Jacquelyn; Plunkett, Mary H; Hoben, John P; Barney, Brett M; Carlson, Ross P; Miller, Anne-Frances; Bothner, Brian; King, Paul W; Peters, John W; Seefeldt, Lance C

    2017-08-15

    The biological reduction of dinitrogen (N 2 ) to ammonia (NH 3 ) by nitrogenase is an energetically demanding reaction that requires low-potential electrons and ATP; however, pathways used to deliver the electrons from central metabolism to the reductants of nitrogenase, ferredoxin or flavodoxin, remain unknown for many diazotrophic microbes. The FixABCX protein complex has been proposed to reduce flavodoxin or ferredoxin using NADH as the electron donor in a process known as electron bifurcation. Herein, the FixABCX complex from Azotobacter vinelandii was purified and demonstrated to catalyze an electron bifurcation reaction: oxidation of NADH (E m = -320 mV) coupled to reduction of flavodoxin semiquinone (E m = -460 mV) and reduction of coenzyme Q (E m = 10 mV). Knocking out fix genes rendered Δrnf A. vinelandii cells unable to fix dinitrogen, confirming that the FixABCX system provides another route for delivery of electrons to nitrogenase. Characterization of the purified FixABCX complex revealed the presence of flavin and iron-sulfur cofactors confirmed by native mass spectrometry, electron paramagnetic resonance spectroscopy, and transient absorption spectroscopy. Transient absorption spectroscopy further established the presence of a short-lived flavin semiquinone radical, suggesting that a thermodynamically unstable flavin semiquinone may participate as an intermediate in the transfer of an electron to flavodoxin. A structural model of FixABCX, generated using chemical cross-linking in conjunction with homology modeling, revealed plausible electron transfer pathways to both high- and low-potential acceptors. Overall, this study informs a mechanism for electron bifurcation, offering insight into a unique method for delivery of low-potential electrons required for energy-intensive biochemical conversions.

  6. The Electron Bifurcating FixABCX Protein Complex from Azotobacter vinelandii: Generation of Low-Potential Reducing Equivalents for Nitrogenase Catalysis

    DOE PAGES

    Ledbetter, Rhesa N.; Garcia Costas, Amaya M.; Lubner, Carolyn E.; ...

    2017-07-13

    The biological reduction of dinitrogen (N 2) to ammonia (NH 3) by nitrogenase is an energetically demanding reaction that requires low-potential electrons and ATP; however, pathways used to deliver the electrons from central metabolism to the reductants of nitrogenase, ferredoxin or flavodoxin, remain unknown for many diazotrophic microbes. The FixABCX protein complex has been proposed to reduce flavodoxin or ferredoxin using NADH as the electron donor in a process known as electron bifurcation. Herein, the FixABCX complex from Azotobacter vinelandii was purified and demonstrated to catalyze an electron bifurcation reaction: oxidation of NADH (E m = -320 mV) coupled tomore » reduction of flavodoxin semiquinone (E m = -460 mV) and reduction of coenzyme Q (E m = 10 mV). Knocking out fix genes rendered ..delta..rnf A. vinelandii cells unable to fix dinitrogen, confirming that the FixABCX system provides another route for delivery of electrons to nitrogenase. Characterization of the purified FixABCX complex revealed the presence of flavin and iron-sulfur cofactors confirmed by native mass spectrometry, electron paramagnetic resonance spectroscopy, and transient absorption spectroscopy. Transient absorption spectroscopy further established the presence of a short-lived flavin semiquinone radical, suggesting that a thermodynamically unstable flavin semiquinone may participate as an intermediate in the transfer of an electron to flavodoxin. A structural model of FixABCX, generated using chemical cross-linking in conjunction with homology modeling, revealed plausible electron transfer pathways to both high- and low-potential acceptors. Altogether, this study informs a mechanism for electron bifurcation, offering insight into a unique method for delivery of low-potential electrons required for energy-intensive biochemical conversions.« less

  7. An inverted cylindrical sputter magnetron as metal vapor supply for electron cyclotron resonance ion sources.

    PubMed

    Weichsel, T; Hartung, U; Kopte, T; Zschornack, G; Kreller, M; Silze, A

    2014-05-01

    An inverted cylindrical sputter magnetron device has been developed. The magnetron is acting as a metal vapor supply for an electron cyclotron resonance (ECR) ion source. FEM simulation of magnetic flux density was used to ensure that there is no critical interaction between both magnetic fields of magnetron and ECR ion source. Spatially resolved double Langmuir probe and optical emission spectroscopy measurements show an increase in electron density by one order of magnitude from 1 × 10(10) cm(-3) to 1 × 10(11) cm(-3), when the magnetron plasma is exposed to the magnetic mirror field of the ECR ion source. Electron density enhancement is also indicated by magnetron plasma emission photography with a CCD camera. Furthermore, photographs visualize the formation of a localized loss-cone - area, when the magnetron is operated at magnetic mirror field conditions. The inverted cylindrical magnetron supplies a metal atom load rate of R > 1 × 10(18) atoms/s for aluminum, which meets the demand for the production of a milliampere Al(+) ion beam.

  8. Deformable devices with integrated functional nanomaterials for wearable electronics.

    PubMed

    Kim, Jaemin; Lee, Jongsu; Son, Donghee; Choi, Moon Kee; Kim, Dae-Hyeong

    2016-01-01

    As the market and related industry for wearable electronics dramatically expands, there are continuous and strong demands for flexible and stretchable devices to be seamlessly integrated with soft and curvilinear human skin or clothes. However, the mechanical mismatch between the rigid conventional electronics and the soft human body causes many problems. Therefore, various prospective nanomaterials that possess a much lower flexural rigidity than their bulk counterparts have rapidly established themselves as promising electronic materials replacing rigid silicon and/or compound semiconductors in next-generation wearable devices. Many hybrid structures of multiple nanomaterials have been also developed to pursue both high performance and multifunctionality. Here, we provide an overview of state-of-the-art wearable devices based on one- or two-dimensional nanomaterials (e.g., carbon nanotubes, graphene, single-crystal silicon and oxide nanomembranes, organic nanomaterials and their hybrids) in combination with zero-dimensional functional nanomaterials (e.g., metal/oxide nanoparticles and quantum dots). Starting from an introduction of materials strategies, we describe device designs and the roles of individual ones in integrated systems. Detailed application examples of wearable sensors/actuators, memories, energy devices, and displays are also presented.

  9. Isolated terawatt attosecond hard X-ray pulse generated from single current spike.

    PubMed

    Shim, Chi Hyun; Parc, Yong Woon; Kumar, Sandeep; Ko, In Soo; Kim, Dong Eon

    2018-05-10

    Isolated terawatt (TW) attosecond (as) hard X-ray pulse is greatly desired for four-dimensional investigations of natural phenomena with picometer spatial and attosecond temporal resolutions. Since the demand for such sources is continuously increasing, the possibility of generating such pulse by a single current spike without the use of optical or electron delay units in an undulator line is addressed. The conditions of a current spike (width and height) and a modulation laser pulse (wavelength and power) is also discussed. We demonstrate that an isolated TW-level as a hard X-ray can be produced by a properly chosen single current spike in an electron bunch with simulation results. By using realistic specifications of an electron bunch of the Pohang Accelerator Laboratory X-ray Free-Electron Laser (PAL-XFEL), we show that an isolated, >1.0 TW and ~36 as X-ray pulse at 12.4 keV can be generated in an optimized-tapered undulator line. This result opens a new vista for current XFEL operation: the attosecond XFEL.

  10. A general way for quantitative magnetic measurement by transmitted electrons

    NASA Astrophysics Data System (ADS)

    Song, Dongsheng; Li, Gen; Cai, Jianwang; Zhu, Jing

    2016-01-01

    EMCD (electron magnetic circular dichroism) technique opens a new door to explore magnetic properties by transmitted electrons. The recently developed site-specific EMCD technique makes it possible to obtain rich magnetic information from the Fe atoms sited at nonequivalent crystallographic planes in NiFe2O4, however it is based on a critical demand for the crystallographic structure of the testing sample. Here, we have further improved and tested the method for quantitative site-specific magnetic measurement applicable for more complex crystallographic structure by using the effective dynamical diffraction effects (general routine for selecting proper diffraction conditions, making use of the asymmetry of dynamical diffraction for design of experimental geometry and quantitative measurement, etc), and taken yttrium iron garnet (Y3Fe5O12, YIG) with more complex crystallographic structure as an example to demonstrate its applicability. As a result, the intrinsic magnetic circular dichroism signals, spin and orbital magnetic moment of iron with site-specific are quantitatively determined. The method will further promote the development of quantitative magnetic measurement with high spatial resolution by transmitted electrons.

  11. Universal electronics for miniature and automated chemical assays.

    PubMed

    Urban, Pawel L

    2015-02-21

    This minireview discusses universal electronic modules (generic programmable units) and their use by analytical chemists to construct inexpensive, miniature or automated devices. Recently, open-source platforms have gained considerable popularity among tech-savvy chemists because their implementation often does not require expert knowledge and investment of funds. Thus, chemistry students and researchers can easily start implementing them after a few hours of reading tutorials and trial-and-error. Single-board microcontrollers and micro-computers such as Arduino, Teensy, Raspberry Pi or BeagleBone enable collecting experimental data with high precision as well as efficient control of electric potentials and actuation of mechanical systems. They are readily programmed using high-level languages, such as C, C++, JavaScript or Python. They can also be coupled with mobile consumer electronics, including smartphones as well as teleinformatic networks. More demanding analytical tasks require fast signal processing. Field-programmable gate arrays enable efficient and inexpensive prototyping of high-performance analytical platforms, thus becoming increasingly popular among analytical chemists. This minireview discusses the advantages and drawbacks of universal electronic modules, considering their application in prototyping and manufacture of intelligent analytical instrumentation.

  12. Decoupling electron and ion storage and the path from interfacial storage to artificial electrodes

    NASA Astrophysics Data System (ADS)

    Chen, Chia-Chin; Maier, Joachim

    2018-02-01

    The requirements for rechargeable batteries place high demands on the electrodes. Efficient storage means accommodating both ions and electrons, not only in substantial amounts, but also with substantial velocities. The materials' space could be largely extended by decoupling the roles of ions and electrons such that transport and accommodation of ions take place in one phase of a composite, and transport and accommodation of electrons in the other phase. Here we discuss this synergistic concept being equally applicable for positive and negative electrodes along with examples from the literature for Li-based and Ag-based cells. Not only does the concept have the potential to mitigate the trade-off between power density and energy density, it also enables a generalized view of bulk and interfacial storage as necessary for nanocrystals. It furthermore allows for testable predictions of heterogeneous storage in passivation layers, dependence of transfer resistance on the state of charge, or heterogeneous storage of hydrogen at appropriate contacts. We also present an outlook on constructing artificial mixed-conductor electrodes that have the potential to achieve both high energy density and high power density.

  13. Design of an X -band electron linear accelerator dedicated to decentralized 99Mo/99mTc supply: From beam energy selection to yield estimation

    NASA Astrophysics Data System (ADS)

    Jang, Jaewoong; Yamamoto, Masashi; Uesaka, Mitsuru

    2017-10-01

    The most frequently used radionuclide in diagnostic nuclear medicine, 99mTc, is generally obtained by the decay of its parent radionuclide, 99Mo. Recently, concerns have been raised over shortages of 99Mo/99mTc, owing to aging of the research reactors which have been supplying practically all of the global demand for 99Mo in a centralized fashion. In an effort to prevent such 99Mo/99mTc supply disruption and, furthermore, to ameliorate the underlying instability of the centralized 99Mo/99mTc supply chain, we designed an X -band electron linear accelerator which can be distributed over multiple regions, whereby 99Mo/99mTc can be supplied with improved accessibility. The electron beam energy was designed to be 35 MeV, at which an average beam power of 9.1 kW was calculated by the following beam dynamics analysis. Subsequent radioactivity modeling suggests that 11 of the designed electron linear accelerators can realize self-sufficiency of 99Mo/99mTc in Japan.

  14. Design and Implementation of Improved Electronic Load Controller for Self-Excited Induction Generator for Rural Electrification

    PubMed Central

    Kathirvel, C.; Porkumaran, K.; Jaganathan, S.

    2015-01-01

    This paper offers an alternative technique, namely, Improved Electronic Load Controller (IELC), which is proposal to improve power quality, maintaining voltage at frequency desired level for rural electrification. The design and development of IELC are considered as microhydroenergy system. The proposed work aims to concentrate on the new schemes for rural electrification with the help of different kinds of hybrid energy systems. The objective of the proposed scheme is to maintain the speed of generation against fluctuating rural demand. The Electronic Load Controller (ELC) is used to connect and disconnect the dump load during the operation of the system, and which absorbs the load when consumer are not in active will enhance the lifestyle of the rural population and improve the living standards. Hydroelectricity is a promising option for electrification of remote villages in India. The conventional methods are not suitable to act as standalone system. Hence, the designing of a proper ELC is essential. The improved electronic load control performance tested with simulation at validated through hardware setup. PMID:26783553

  15. Design and Implementation of Improved Electronic Load Controller for Self-Excited Induction Generator for Rural Electrification.

    PubMed

    Kathirvel, C; Porkumaran, K; Jaganathan, S

    2015-01-01

    This paper offers an alternative technique, namely, Improved Electronic Load Controller (IELC), which is proposal to improve power quality, maintaining voltage at frequency desired level for rural electrification. The design and development of IELC are considered as microhydroenergy system. The proposed work aims to concentrate on the new schemes for rural electrification with the help of different kinds of hybrid energy systems. The objective of the proposed scheme is to maintain the speed of generation against fluctuating rural demand. The Electronic Load Controller (ELC) is used to connect and disconnect the dump load during the operation of the system, and which absorbs the load when consumer are not in active will enhance the lifestyle of the rural population and improve the living standards. Hydroelectricity is a promising option for electrification of remote villages in India. The conventional methods are not suitable to act as standalone system. Hence, the designing of a proper ELC is essential. The improved electronic load control performance tested with simulation at validated through hardware setup.

  16. Deformable devices with integrated functional nanomaterials for wearable electronics

    NASA Astrophysics Data System (ADS)

    Kim, Jaemin; Lee, Jongsu; Son, Donghee; Choi, Moon Kee; Kim, Dae-Hyeong

    2016-03-01

    As the market and related industry for wearable electronics dramatically expands, there are continuous and strong demands for flexible and stretchable devices to be seamlessly integrated with soft and curvilinear human skin or clothes. However, the mechanical mismatch between the rigid conventional electronics and the soft human body causes many problems. Therefore, various prospective nanomaterials that possess a much lower flexural rigidity than their bulk counterparts have rapidly established themselves as promising electronic materials replacing rigid silicon and/or compound semiconductors in next-generation wearable devices. Many hybrid structures of multiple nanomaterials have been also developed to pursue both high performance and multifunctionality. Here, we provide an overview of state-of-the-art wearable devices based on one- or two-dimensional nanomaterials (e.g., carbon nanotubes, graphene, single-crystal silicon and oxide nanomembranes, organic nanomaterials and their hybrids) in combination with zero-dimensional functional nanomaterials (e.g., metal/oxide nanoparticles and quantum dots). Starting from an introduction of materials strategies, we describe device designs and the roles of individual ones in integrated systems. Detailed application examples of wearable sensors/actuators, memories, energy devices, and displays are also presented.

  17. Laser-Hybrid welding, an innovative technology to join automotive body parts

    NASA Astrophysics Data System (ADS)

    Sieben, Manuel; Brunnecker, Frank

    The design of Tail lamps has been changed dramatically since cars built. At modern lamps, the lenses are absolutely transparent and allow a direct view onto the weld seam. Conventional welding technologies, such as vibration and hot plate welding cannot compete with this demand. Focused on this targeted application, LPKF Laser & Electronics AG has developed in cooperation with the Bavarian Laser Centre a unique Laser welding technology called hybrid welding.

  18. STAR Performance with SPEAR (Signal Processing Electronic Attack RFIC)

    DTIC Science & Technology

    2017-03-01

    STAR operation in the presence of 1 kW EIRP power , independently of the choice of transmitter in use. The paper reports on the status of the SPEAR...prototype will be presented. To the authors’ knowledge , the measured results from the prototype already demonstrate state-of-the-art STAR performance...self-generated high power interferers. SPEAR is an innovative approach to the full duplex challenge that meets the high demands of military systems

  19. Direct Electricity from Heat: A Solution to Assist Aircraft Power Demands

    NASA Technical Reports Server (NTRS)

    Goldsby, Jon C.

    2010-01-01

    A thermionic device produces an electrical current with the application of a thermal gradient whereby the temperature at one electrode provides enough thermal energy to eject electrons. The system is totally predicated on the thermal gradient and the work function of the electrode collector relative to the emitter electrode. Combined with a standard thermoelectric device high efficiencies may result, capable of providing electrical energy from the waste heat of gas turbine engines.

  20. Innovative research on the group teaching mode based on the LabVIEW virtual environment

    NASA Astrophysics Data System (ADS)

    Liang, Pei; Huang, Jie; Gong, Hua-ping; Dong, Qian-min; Dong, Yan-yan; Sun, Cai-xia

    2017-08-01

    This paper discusses the widely existing problems of increasing demand of professional engineer in electronic science major and the backward of the teaching mode at present. From one specialized course "Virtual Instrument technique and LABVIEW programming", we explore the new group-teaching mode based on the Virtual Instrument technique, and then the Specific measures and implementation procedures and effect of this teaching mode summarized in the end.

  1. The State of 21st Century Learning in the K-12 World of the United States: Online and Blended Learning Opportunities for American Elementary and Secondary Students

    ERIC Educational Resources Information Center

    Greene, Kimberly; Hale, William

    2017-01-01

    This paper is an examination of the current state of blended and online learning throughout the K-12 world in the United States. The analysis is predicated upon the potential of electronically-mediated learning (e-learning) to effectively prepare students for the demands of 21st century citizenship through the affordances of such learning…

  2. Fe(II)/Fe(III)-Catalyzed Intramolecular Didehydro-Diels-Alder Reaction of Styrene-ynes.

    PubMed

    Mun, Hyeon Jin; Seong, Eun Young; Ahn, Kwang-Hyun; Kang, Eun Joo

    2018-02-02

    The intramolecular didehydro-Diels-Alder reaction of styrene-ynes was catalyzed by Fe(II) and Fe(III) to produce various naphthalene derivatives under microwave heating conditions. Mechanistic calculations found that the Fe(II) catalyst activates the styrenyl diene in an inverse-electron-demand Diels-Alder reaction, and the consecutive dehydrogenation reaction can be promoted by either Fe(II)-catalyzed direct dehydrogenation or an Fe(III)-catalyzed rearomatization/dehydrogenation pathway.

  3. Electrochemical Study of Corrosion Phenomena in Zirconium Alloys

    DTIC Science & Technology

    2005-06-01

    required reaction rates [1.1]. Based predominantly on this fact, zirconium alloys were chosen to sheath, or clad, the fuel. With the increasing demand...cathode or anode. As the oxidation and reduction reactions occur, a galvanic cell is developed. The electrons on the anode are released from the metallic...matrix as the ions are released into the aqueous solution in the initial half-cell reaction . The second half-cell reaction , taking place on the

  4. Melding Vapor-Phase Organic Chemistry and Textile Manufacturing To Produce Wearable Electronics.

    PubMed

    Andrew, Trisha L; Zhang, Lushuai; Cheng, Nongyi; Baima, Morgan; Kim, Jae Joon; Allison, Linden; Hoxie, Steven

    2018-04-17

    Body-mountable electronics and electronically active garments are the future of portable, interactive devices. However, wearable devices and electronic garments are demanding technology platforms because of the large, varied mechanical stresses to which they are routinely subjected, which can easily abrade or damage microelectronic components and electronic interconnects. Furthermore, aesthetics and tactile perception (or feel) can make or break a nascent wearable technology, irrespective of device metrics. The breathability and comfort of commercial fabrics is unmatched. There is strong motivation to use something that is already familiar, such as cotton/silk thread, fabrics, and clothes, and imperceptibly adapt it to a new technological application. (24) Especially for smart garments, the intrinsic breathability, comfort, and feel of familiar fabrics cannot be replicated by devices built on metalized synthetic fabrics or cladded, often-heavy designer fibers. We propose that the strongest strategy to create long-lasting and impactful electronic garments is to start with a mass-produced article of clothing, fabric, or thread/yarn and coat it with conjugated polymers to yield various textile circuit components. Commonly available, mass-produced fabrics, yarns/threads, and premade garments can in theory be transformed into a plethora of comfortably wearable electronic devices upon being coated with films of electronically active conjugated polymers. The definitive hurdle is that premade garments, threads, and fabrics have densely textured, three-dimensional surfaces that display roughness over a large range of length scales, from microns to millimeters. Tremendous variation in the surface morphology of conjugated-polymer-coated fibers and fabrics can be observed with different coating or processing conditions. In turn, the morphology of the conjugated polymer active layer determines the electrical performance and, most importantly, the device ruggedness and lifetime. Reactive vapor coating methods allow a conjugated polymer film to be directly formed on the surface of any premade garment, prewoven fabric, or fiber/yarn substrate without the need for specialized processing conditions, surface pretreatments, detergents, or fixing agents. This feature allows electronic coatings to be applied at the end of existing, high-throughput textile and garment manufacturing routines, irrespective of dye content or surface finish of the final textile. Furthermore, reactive vapor coating produces conductive materials without any insulating moieties and yields uniform and conformal films on fiber/fabric surfaces that are notably wash- and wear-stable and can withstand mechanically demanding textile manufacturing routines. These unique features mean that rugged and practical textile electronic devices can be created using sewing, weaving, or knitting procedures without compromising or otherwise affecting the surface electronic coating. In this Account, we highlight selected electronic fabrics and garments created by melding reactive vapor deposition with traditional textile manipulation processes, including electrically heated gloves that are lightweight, breathable, and sweat-resistant; surface-coated cotton, silk, and bast fiber threads capable of carrying large current densities and acting as sewable circuit interconnects; and surface-coated nylon threads woven together to form triboelectric textiles that can convert surface charge created during small body movements into usable and storable power.

  5. Pb-free surface-finishing on electronic components' terminals for Pb-free soldering assembly

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tanaka, Hitoshi; Tanimoto, Morimasa; Matsuda, Akira

    1999-11-01

    Pb-free solderable surface finishing is essential to implement Pb-free solder assembly in order to meet with the growing demand of environmental consciousness to eliminate Pb from electronic products. Two types of widely applicable Pb-free surface finishing technologies are developed. One is the multilayer-system including Pd with Ni undercoat. Heat-resistance of Pd enables whole-surface-plating on to leadframe before IC-assembling process. The other is the double-layer-system with low-melting-point-materials, for example, thicker Sn underlayer and thinner Sn-Bi alloy overlayer, dilutes Sn-Bi alloy's defects of harmful reactivity along with substrate metal and mechanical brittleness with keeping its advantages of solder-wettability and no whisker.

  6. MXene: a potential candidate for yarn supercapacitors.

    PubMed

    Zhang, Jizhen; Seyedin, Shayan; Gu, Zhoujie; Yang, Wenrong; Wang, Xungai; Razal, Joselito M

    2017-12-07

    The increasing developments in wearable electronics demand compatible power sources such as yarn supercapacitors (YSCs) that can effectively perform in a limited footprint. MXene nanosheets, which have been recently shown in the literature to possess ultra-high volumetric capacitance, were used in this study for the fabrication of YSCs in order to identify their potential merit and performance in YSCs. With the aid of a conductive binder (PEDOT-PSS), YSCs with high mass loading of MXene are demonstrated. These MXene-based YSCs exhibit excellent device performance and stability even under bending and twisting. This study demonstrates that MXene is a promising candidate for YSCs and its further development can lead to flexible power sources with sufficient performance for powering miniaturized and/or wearable electronics.

  7. The origin of the ligand-controlled regioselectivity in Rh-catalyzed [(2 + 2) + 2] carbocyclizations: steric vs. stereoelectronic effects.

    PubMed

    Crandell, Douglas W; Mazumder, Shivnath; Evans, P Andrew; Baik, Mu-Hyun

    2015-12-01

    Density functional theory calculations demonstrate that the reversal of regiochemical outcome of the addition for substituted methyl propiolates in the rhodium-catalyzed [(2 + 2) + 2] carbocyclization with PPh 3 and ( S )-xyl-binap as ligands is both electronically and sterically controlled. For example, the ester functionality polarizes the alkyne π* orbital to favor overlap of the methyl-substituted terminus of the alkyne with the p π -orbital of the alkenyl fragment of the rhodacycle during alkyne insertion with PPh 3 as the ligand. In contrast, the sterically demanding xyl-binap ligand cannot accommodate the analogous alkyne orientation, thereby forcing insertion to occur at the sterically preferred ester terminus, overriding the electronically preferred orientation for alkyne insertion.

  8. From the Office of the National Coordinator: the strategy for advancing the exchange of health information.

    PubMed

    Williams, Claudia; Mostashari, Farzad; Mertz, Kory; Hogin, Emily; Atwal, Parmeeth

    2012-03-01

    Electronic health information exchange addresses a critical need in the US health care system to have information follow patients to support patient care. Today little information is shared electronically, leaving doctors without the information they need to provide the best care. With payment reforms providing a strong business driver, the demand for health information exchange is poised to grow. The Office of the National Coordinator for Health Information Technology, Department of Health and Human Services, has led the process of establishing the essential building blocks that will support health information exchange. Over the coming year, this office will develop additional policies and standards that will make information exchange easier and cheaper and facilitate its use on a broader scale.

  9. Water-resources data for the United States: water year 2011

    USGS Publications Warehouse

    ,

    2011-01-01

    Water resources data are published annually for use by engineers, scientists, managers, educators, and the general public. These archival products supplement direct access to current and historical water data provided by NWISWeb. Beginning with Water Year 2006, annual water data reports are available as individual electronic Site Data Sheets for the entire Nation for retrieval, download, and localized printing on demand. National distribution includes tabular and map interfaces for search, query, display and download of data. From 1962 until 2005, reports were published by State as paper documents, although most reports since the mid-1990s are also available in electronic form through this web page. Reports prior to 1962 were published in occasional USGS Water-Supply Papers and other reports.

  10. Water-resources data for the United States: water year 2010

    USGS Publications Warehouse

    ,

    2010-01-01

    Water resources data are published annually for use by engineers, scientists, managers, educators, and the general public. These archival products supplement direct access to current and historical water data provided by NWISWeb. Beginning with Water Year 2006, annual water data reports are available as individual electronic Site Data Sheets for the entire Nation for retrieval, download, and localized printing on demand. National distribution includes tabular and map interfaces for search, query, display and download of data. From 1962 until 2005, reports were published by State as paper documents, although most reports since the mid-1990s are also available in electronic form through this web page. Reports prior to 1962 were published in occasional USGS Water-Supply Papers and other reports.

  11. Water-resources data for the United States: water year 2007

    USGS Publications Warehouse

    ,

    2007-01-01

    Water resources data are published annually for use by engineers, scientists, managers, educators, and the general public. These archival products supplement direct access to current and historical water data provided by NWISWeb. Beginning with Water Year 2006, annual water data reports are available as individual electronic Site Data Sheets for the entire Nation for retrieval, download, and localized printing on demand. National distribution includes tabular and map interfaces for search, query, display and download of data. From 1962 until 2005, reports were published by State as paper documents, although most reports since the mid-1990s are also available in electronic form through this web page. Reports prior to 1962 were published in occasional USGS Water-Supply Papers and other reports.

  12. Water-resources data for the United States: water year 2008

    USGS Publications Warehouse

    ,

    2008-01-01

    Water resources data are published annually for use by engineers, scientists, managers, educators, and the general public. These archival products supplement direct access to current and historical water data provided by NWISWeb. Beginning with Water Year 2006, annual water data reports are available as individual electronic Site Data Sheets for the entire Nation for retrieval, download, and localized printing on demand. National distribution includes tabular and map interfaces for search, query, display and download of data. From 1962 until 2005, reports were published by State as paper documents, although most reports since the mid-1990s are also available in electronic form through this web page. Reports prior to 1962 were published in occasional USGS Water-Supply Papers and other reports.

  13. Europium Silicide – a Prospective Material for Contacts with Silicon

    PubMed Central

    Averyanov, Dmitry V.; Tokmachev, Andrey M.; Karateeva, Christina G.; Karateev, Igor A.; Lobanovich, Eduard F.; Prutskov, Grigory V.; Parfenov, Oleg E.; Taldenkov, Alexander N.; Vasiliev, Alexander L.; Storchak, Vyacheslav G.

    2016-01-01

    Metal-silicon junctions are crucial to the operation of semiconductor devices: aggressive scaling demands low-resistive metallic terminals to replace high-doped silicon in transistors. It suggests an efficient charge injection through a low Schottky barrier between a metal and Si. Tremendous efforts invested into engineering metal-silicon junctions reveal the major role of chemical bonding at the interface: premier contacts entail epitaxial integration of metal silicides with Si. Here we present epitaxially grown EuSi2/Si junction characterized by RHEED, XRD, transmission electron microscopy, magnetization and transport measurements. Structural perfection leads to superb conductivity and a record-low Schottky barrier with n-Si while an antiferromagnetic phase invites spin-related applications. This development opens brand-new opportunities in electronics. PMID:27211700

  14. Europium Silicide - a Prospective Material for Contacts with Silicon.

    PubMed

    Averyanov, Dmitry V; Tokmachev, Andrey M; Karateeva, Christina G; Karateev, Igor A; Lobanovich, Eduard F; Prutskov, Grigory V; Parfenov, Oleg E; Taldenkov, Alexander N; Vasiliev, Alexander L; Storchak, Vyacheslav G

    2016-05-23

    Metal-silicon junctions are crucial to the operation of semiconductor devices: aggressive scaling demands low-resistive metallic terminals to replace high-doped silicon in transistors. It suggests an efficient charge injection through a low Schottky barrier between a metal and Si. Tremendous efforts invested into engineering metal-silicon junctions reveal the major role of chemical bonding at the interface: premier contacts entail epitaxial integration of metal silicides with Si. Here we present epitaxially grown EuSi2/Si junction characterized by RHEED, XRD, transmission electron microscopy, magnetization and transport measurements. Structural perfection leads to superb conductivity and a record-low Schottky barrier with n-Si while an antiferromagnetic phase invites spin-related applications. This development opens brand-new opportunities in electronics.

  15. PROCESS DEVELOPMENT FOR THE RECOVERY OF CRITICAL MATERIALS FROM ELECTRONIC WASTE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lister, T. E.; Diaz, L. A.; Clark, G. G.

    As electronic technology continues to evolve there is a growing need to develop processes which recover valuable material from antiquated technology. This need follows from the environmental challenges associated with the availability of raw materials and fast growing generation of electronic waste. Although just present in small quantities in electronic devices, the availability of raw materials, such as rare earths and precious metals, becomes critical for the production of high tech electronic devices and the development of green technologies (i.e. wind turbines, electric motors, and solar panels). Therefore, the proper recycling and processing of increasing volumes of electronic waste presentmore » an opportunity to stabilize the market of critical materials, reducing the demand of mined products, and providing a proper disposal and treatment of a hazardous waste stream. This paper will describe development and techno-economic assessment of a comprehensive process for the recovery of value and critical materials from electronic waste. This hydrometallurgical scheme aims to selectively recover different value segments in the materials streams (base metals, precious metals, and rare earths). The economic feasibility for the recovery of rare earths from electronic waste is mostly driven by the efficient recovery of precious metals, such as Au and Pd (ca. 80 % of the total recoverable value). Rare earth elements contained in magnets (speakers, vibrators and hard disk storage) can be recovered as a mixture of rare earths oxides which can later be reduced to the production of new magnets.« less

  16. Semiconductors: Still a Wide Open Frontier for Scientists/Engineers

    NASA Astrophysics Data System (ADS)

    Seiler, David G.

    1997-10-01

    A 1995 Business Week article described several features of the explosive use of semiconductor chips today: ``Booming'' personal computer markets are driving high demand for microprocessors and memory chips; (2) New information superhighway markets will `ignite' sales of multimedia and communication chips; and (3) Demand for digital-signal-processing and data-compression chips, which speed up video and graphics, is `red hot.' A Washington Post article by Stan Hinden said that technology is creating an unstoppable demand for electronic elements. This ``digital pervasiveness'' means that a semiconductor chip is going into almost every high-tech product that people buy - cars, televisions, video recorders, telephones, radios, alarm clocks, coffee pots, etc. ``Semiconductors are everywhere.'' Silicon and compound semiconductors are absolutely essential and are pervasive enablers for DoD operations and systems. DoD's Critical Technologies Plan of 1991 says that ``Semiconductor materials and microelectronics are critically important and appropriately lead the list of critical defense technologies.'' These trends continue unabated. This talk describes some of the frontiers of semiconductors today and shows how scientists and engineers can effectively contribute to its advancement. Cooperative, multidisciplinary efforts are increasing. Specific examples will be given for scanning capacitance microscopy and thin-film metrology.

  17. Development of an Agent-based Model to Analyze Contemporary Helium Markets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Riddle, Matthew E.; Uckun, Canan; Conzelmann, Guenter

    Although U.S. helium demand has remained relatively flat since 2009, exports of helium have increased significantly since then, driven primarily by demand for electronic and semiconductor manufacturing in Asia. In the midst of this global demand shift, the Helium Act dictates a new procedure for pricing and distributing the gas through a reserve that historically functioned as a loose “oligarchy.” The new procedure requires prices to be determined by the open market through auctions and a survey of market prices, as opposed to increasing prices according to the consumer price index. Response to these changes has caused temporary shortages, pricemore » increases, and a significant increase in the development of the helium extraction technologies used to produce helium from formerly marginal sources. Technologies are being developed and refined to extract helium from formerly low-yielding natural gas fields containing much lower amounts of helium than the previously considered economic threshold of 0.3%. Combining these transformative policies with the potential for new and significant global supplies from Qatar, Algeria, and Russia could lead to new and unforeseen market behaviors and reactions from global helium markets. The objective of the project is to analyze the global helium markets.« less

  18. Trends in laser micromachining

    NASA Astrophysics Data System (ADS)

    Gaebler, Frank; van Nunen, Joris; Held, Andrew

    2016-03-01

    Laser Micromachining is well established in industry. Depending on the application lasers with pulse length from μseconds to femtoseconds and wavelengths from 1064nm and its harmonics up to 5μm or 10.6μm are used. Ultrafast laser machining using pulses with pico or femtosecond duration pulses is gaining traction, as it offers very precise processing of materials with low thermal impact. Large-scale industrial ultrafast laser applications show that the market can be divided into various sub segments. One set of applications demand low power around 10W, compact footprint and are extremely sensitive to the laser price whilst still demanding 10ps or shorter laser pulses. A second set of applications are very power hungry and only become economically feasible for large scale deployments at power levels in the 100+W class. There is also a growing demand for applications requiring fs-laser pulses. In our presentation we would like to describe these sub segments by using selected applications from the automotive and electronics industry e.g. drilling of gas/diesel injection nozzles, dicing of LED substrates. We close the presentation with an outlook to micromachining applications e.g. glass cutting and foil processing with unique new CO lasers emitting 5μm laser wavelength.

  19. Job crafting among health care professionals: The role of work engagement.

    PubMed

    Bakker, Arnold B

    2018-04-01

    The aim of this study was to examine the impact of job crafting on the quality of the work environment of health care professionals. Job crafting refers to proactive behavior aimed at optimizing the fit between person and job. Using job demands-resources theory, we hypothesized that job crafting would be positively related to job resources and person-organisation fit, and negatively to hindrance demands. Furthermore, we hypothesized that these relationships would be qualified by work engagement. A total of 5,272 health care professionals from one of 35 different organisations filled out an electronic questionnaire (response is 55%). Regression analyses were used to test hypotheses. Consistent with hypotheses, job crafting in the form of increasing job resources was positively related to opportunities for development, performance feedback and P-O fit; and negatively related to hindrance job demands - particularly when work engagement was high. The combination of job crafting and work engagement is important for the realization of a resourceful work environment and fit between person and organisation. Interventions aimed at fostering job crafting should be tailored to the motivation of health care professionals. © 2017 John Wiley & Sons Ltd.

  20. Construction of titanium dioxide nanorod/graphite microfiber hybrid electrodes for a high performance electrochemical glucose biosensor

    NASA Astrophysics Data System (ADS)

    Zhang, Jian; Yu, Xin; Guo, Weibo; Qiu, Jichuan; Mou, Xiaoning; Li, Aixue; Liu, Hong

    2016-04-01

    The demand for a highly sensitive and selective glucose biosensor which can be used for implantable or on-time monitoring is constantly increasing. In this work, TiO2 nanorods were synthesized in situ on the surface of graphite microfibers to yield TiO2 nanorod/graphite microfiber hybrid electrodes. The TiO2 nanorods not only retain the high activity of the immobilized glucose molecule, but also promote the direct electron transfer process on the electrode surface. As a working electrode in an electrochemical glucose biosensor in a flowing system, the microfiber hybrid electrodes exhibit high sensitivity, selectivity and stability. Due to its simplicity, low cost, high stability, and unique morphology, the TiO2 nanorod/graphite microfiber hybrid electrode is expected to be an excellent candidate for an implantable biosensor or for in situ flow monitoring.The demand for a highly sensitive and selective glucose biosensor which can be used for implantable or on-time monitoring is constantly increasing. In this work, TiO2 nanorods were synthesized in situ on the surface of graphite microfibers to yield TiO2 nanorod/graphite microfiber hybrid electrodes. The TiO2 nanorods not only retain the high activity of the immobilized glucose molecule, but also promote the direct electron transfer process on the electrode surface. As a working electrode in an electrochemical glucose biosensor in a flowing system, the microfiber hybrid electrodes exhibit high sensitivity, selectivity and stability. Due to its simplicity, low cost, high stability, and unique morphology, the TiO2 nanorod/graphite microfiber hybrid electrode is expected to be an excellent candidate for an implantable biosensor or for in situ flow monitoring. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01360k

  1. Progress and Prospects in Stretchable Electroluminescent Devices

    NASA Astrophysics Data System (ADS)

    Wang, Jiangxin; Lee, Pooi See

    2017-03-01

    Stretchable electroluminescent (EL) devices are a new form of mechanically deformable electronics that are gaining increasing interests and believed to be one of the essential technologies for next generation lighting and display applications. Apart from the simple bending capability in flexible EL devices, the stretchable EL devices are required to withstand larger mechanical deformations and accommodate stretching strain beyond 10%. The excellent mechanical conformability in these devices enables their applications in rigorous mechanical conditions such as flexing, twisting, stretching, and folding.The stretchable EL devices can be conformably wrapped onto arbitrary curvilinear surface and respond seamlessly to the external or internal forces, leading to unprecedented applications that cannot be addressed with conventional technologies. For example, they are in demand for wide applications in biomedical-related devices or sensors and soft interactive display systems, including activating devices for photosensitive drug, imaging apparatus for internal tissues, electronic skins, interactive input and output devices, robotics, and volumetric displays. With increasingly stringent demand on the mechanical requirements, the fabrication of stretchable EL device is encountering many challenges that are difficult to resolve. In this review, recent progresses in the stretchable EL devices are covered with a focus on the approaches that are adopted to tackle materials and process challenges in stretchable EL devices and delineate the strategies in stretchable electronics. We first introduce the emission mechanisms that have been successfully demonstrated on stretchable EL devices. Limitations and advantages of the different mechanisms for stretchable EL devices are also discussed. Representative reports are reviewed based on different structural and material strategies. Unprecedented applications that have been enabled by the stretchable EL devices are reviewed. Finally, we summarize with our perspectives on the approaches for the stretchable EL devices and our proposals on the future development in these devices.

  2. Behavioral economic substitution between conventional cigarettes and e-cigarettes differs as a function of the frequency of e-cigarette use.

    PubMed

    Snider, Sarah E; Cummings, K Michael; Bickel, Warren K

    2017-08-01

    Models measuring the interactions between consumption of conventional cigarettes and electronic cigarettes (e-cigarettes) in the marketplace are becoming vital forecast tools as the popularity of e-cigarettes increases and policy on tobacco products changes. Behavioral economics, which involves the integration of psychology and consumer demand, can be used to measure individuals' purchase behavior under different marketplace conditions. Our goal was to measure hypothetical conventional cigarette and e-cigarette purchasing among smokers with varying e-cigarette use patterns. Daily cigarette smokers were recruited using Amazon Mechanical Turk, an online crowdsourcing tool. Participants were asked about their frequency of e-cigarette use and to complete hypothetical single and cross-commodity purchase tasks. Frequency of e-cigarette use differentially affected how individuals consumed both conventional and e- cigarettes in different hypothetical marketplace conditions. The present study demonstrates four main findings: 1) the demand for conventional cigarettes was the lowest in those with greater frequency of e-cigarette use, 2) the demand for e-cigarettes was the highest in those with greater frequency of e-cigarette use, 3) when both products were available together, daily e-cigarette users purchased more e-cigarettes, but e-cigarettes served as a substitute for cigarettes in all groups regardless of frequency of use, and 4) the demand for conventional cigarette demand was lower in frequent e-cigarette users when e-cigarettes were concurrently available. Together, these data suggest that price and marketplace conditions will impact purchasing behavior of conventional and e-cigarettes users heterogeneously. Therefore, frequency of use patterns should be considered when implementing novel policies and/or marketplace changes. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. A hybrid optical switch architecture to integrate IP into optical networks to provide flexible and intelligent bandwidth on demand for cloud computing

    NASA Astrophysics Data System (ADS)

    Yang, Wei; Hall, Trevor J.

    2013-12-01

    The Internet is entering an era of cloud computing to provide more cost effective, eco-friendly and reliable services to consumer and business users. As a consequence, the nature of the Internet traffic has been fundamentally transformed from a pure packet-based pattern to today's predominantly flow-based pattern. Cloud computing has also brought about an unprecedented growth in the Internet traffic. In this paper, a hybrid optical switch architecture is presented to deal with the flow-based Internet traffic, aiming to offer flexible and intelligent bandwidth on demand to improve fiber capacity utilization. The hybrid optical switch is capable of integrating IP into optical networks for cloud-based traffic with predictable performance, for which the delay performance of the electronic module in the hybrid optical switch architecture is evaluated through simulation.

  4. Electricity generation from bio-treatment of sewage sludge with microbial fuel cell.

    PubMed

    Jiang, Junqiu; Zhao, Qingliang; Zhang, Jinna; Zhang, Guodong; Lee, Duu-Jong

    2009-12-01

    A two-chambered microbial fuel cell (MFC) with potassium ferricyanide as its electron acceptor was utilized to degrade excess sewage sludge and to generate electricity. Stable electrical power was produced continuously during operation for 250 h. Total chemical oxygen demand (TCOD) of sludge was reduced by 46.4% when an initial TCOD was 10,850 mg/l. The MFC power output did not significantly depend on process parameters such as substrate concentration, cathode catholyte concentration, and anodic pH. However, the MFC produced power was in close correlation with the soluble chemical oxygen demand (SCOD) of sludge. Furthermore, ultrasonic pretreatment of sludge accelerated organic matter dissolution and, hence, TCOD removal rate in the MFC was increased, but power output was insignificantly enhanced. This study demonstrates that this MFC can generate electricity from sewage sludge over a wide range of process parameters.

  5. Silver Recycling in the United States in 2000

    USGS Publications Warehouse

    Hilliard, Henry E.

    2003-01-01

    In 2000, the global silver supply deficit (the difference between mine and scrap supply and silver demand) was more than 3,000 metric tons. U.S. silver demand for photographic applications alone was nearly equal to annual U.S. silver production. Until 1968, the U.S. silver deficit was filled by withdrawals from the U.S. Treasury reserves. In 2000, the deficit was filled by destocking, imports, and recycling. Photographic wastes, spent catalysts, and electronic scrap are the major sources of materials for silver recycling. Nearly 1,800 tons of silver contained in these materials were available for recycling in 2000. Other recyclable silver-bearing materials include dental alloys, jewelry, and silverware. In 2000, an estimated 1,700 tons of silver were recovered from secondary sources in the United States. The U.S. recycling efficiency for old scrap was calculated to have been 97 percent in 2000; the recycling rate was estimated to be 32 percent.

  6. Silver recycling in the United States in 2000

    USGS Publications Warehouse

    Hilliard, Henry E.

    2003-01-01

    In 2000, the global silver supply deficit (the difference between mine and scrap supply and silver demand) was more than 3,000 metric tons. U.S. silver demand for photographic applications alone was nearly equal to annual U.S. silver production. Until 1968, the U.S. silver deficit was filled by withdrawals from the U.S. Treasury reserves. In 2000, the deficit was filled by destocking, imports, and recycling. Photographic wastes, spent catalysts, and electronic scrap are the major sources of materials for silver recycling. Nearly 1,800 metric tons of silver contained in these materials were available for recycling in 2000. Other recyclable silver-bearing materials include dental alloys, jewelry, and silverware. In 2000, an estimated 1,700 tons of silver were recovered from secondary sources in the United States. The U.S. recycling efficiency for old scrap was calculated to have been 97 percent in 2000; the recycling rate was estimated to be 32 percent.

  7. State-of-the-art radiation detectors for medical imaging: Demands and trends

    NASA Astrophysics Data System (ADS)

    Darambara, Dimitra G.

    2006-12-01

    Over the last half-century a variety of significant technical advances in several scientific fields has been pointing to an exploding growth in the field of medical imaging leading to a better interpretation of more specific anatomical, biochemical and molecular pathways. In particular, the development of novel imaging detectors and readout electronics has been critical to the advancement of medical imaging allowing the invention of breakthrough platforms for simultaneous acquisition of multi-modality images at molecular level. The present paper presents a review of the challenges, demands and constraints on radiation imaging detectors imposed by the nature of the modality and the physics of the imaging source. This is followed by a concise review and perspective on various types of state-of-the-art detector technologies that have been developed to meet these requirements. Trends, prospects and new concepts for future imaging detectors are also highlighted.

  8. The State of Client-Centered Public Service Delivery in the Netherlands

    NASA Astrophysics Data System (ADS)

    Jansen, Jurjen; de Vries, Sjoerd; van der Geest, Thea; Arendsen, Rex; van Dijk, Jan

    Businesses and citizens demand a better and more client-centered way of service delivery from public organizations. As society becomes more complex, dynamic and diverse, public organizations need to adapt to this demand. Conversely, our perception is that public organizations might still treat their target groups as one. However, the need for client-centered public service delivery is growing. This is widely debated in literature. Nonetheless, little empirical evidence is available about the state of client-centeredness of public organizations. The objective of the present study is to identify the state of client-centered public service delivery in the Netherlands. In order to research this topic 400 people from 194 Dutch public organizations were invited to complete an electronic questionnaire. 105 people responded. According to the respondents the state of client-centeredness is acceptable. However, only 25% of the public organizations seem to take differentiation as the point of departure for their service delivery.

  9. The IBM PC at NASA Ames

    NASA Technical Reports Server (NTRS)

    Peredo, James P.

    1988-01-01

    Like many large companies, Ames relies very much on its computing power to get work done. And, like many other large companies, finding the IBM PC a reliable tool, Ames uses it for many of the same types of functions as other companies. Presentation and clarification needs demand much of graphics packages. Programming and text editing needs require simpler, more-powerful packages. The storage space needed by NASA's scientists and users for the monumental amounts of data that Ames needs to keep demand the best database packages that are large and easy to use. Availability to the Micom Switching Network combines the powers of the IBM PC with the capabilities of other computers and mainframes and allows users to communicate electronically. These four primary capabilities of the PC are vital to the needs of NASA's users and help to continue and support the vast amounts of work done by the NASA employees.

  10. Hybrid measurement chains for the SAS-C spacecraft. [advantages over analog signal processing circuits

    NASA Technical Reports Server (NTRS)

    Goeke, R. F.

    1975-01-01

    Spacecraft electronic systems usually demand tight packaging. It was this consideration which initially forced us to consider hybrid circuits for the analog signal processing circuits in the Small Astronomy Satellite-C (SAS-C) scientific payload. We gradually discovered that increased reliability, low power consumption, and reduced program costs all followed. This paper will attempt to share our laboratory's first experience with hybrid circuits and indicate those areas which we found to be important.

  11. Electrospinning synthesis and characterization of PLA-PEG-MNPs composite fibrous membranes

    NASA Astrophysics Data System (ADS)

    Kumar, M.; Klimke, S.; Preiss, A.; Unruh, D.; Wengerowsky, D.; Lehmann, R.; Sindelar, R.; Klingelhöfer, G.; Boča, R.; Renz, F.

    2017-11-01

    An electrospinning technique was used to fabricate PLA, PLA-PEG and PLA-PEG-MNPs composite fibrous membranes. The morphology of electrospun composite membranes were characterized by scanning electron microscope. To test the potential availability of MNPs in PLA-PEG composite membranes, TG, Raman, Mössbauer, VSM and ICP-OES analysis were used. The PLA-PEG composite fibrous membranes showed the presence of MNPs, hence offers the possibility for magnetically triggered on-demand drug delivery.

  12. A Tetrazine-Labile Vinyl Ether Benzyloxycarbonyl Protecting Group (VeZ): An Orthogonal Tool for Solid-Phase Peptide Chemistry.

    PubMed

    Staderini, Matteo; Gambardella, Alessia; Lilienkampf, Annamaria; Bradley, Mark

    2018-06-01

    The vinyl ether benzyloxycarbonyl (VeZ) protecting group is selectively cleaved by treatment with tetrazines via an inverse electron-demand Diels-Alder reaction. This represents a new orthogonal protecting group for solid-phase peptide synthesis, with Fmoc-Lys(VeZ)-OH as a versatile alternative to Fmoc-Lys(Alloc)-OH and Fmoc-Lys(Dde)-OH, as demonstrated by the synthesis of two biologically relevant cyclic peptides.

  13. Finalizing the DTAG: Implementation and Testing of Design Improvements for Reliability and Availability

    DTIC Science & Technology

    2015-09-30

    acoustics and fine scale motion. The success of the Dtag has resulted in an increased demand for the instrument from researchers both within the...sensor blocks sound when the animal is close to the surface. The polyethylene shell was eliminated in the Dtag-3 design to improve acoustic ...into 3 main sub-assemblies (Figure 5): 1) foam sub-assembly, 2) sensor sub-assembly, and 3) Electronics sub-assembly. This separation enables rapid

  14. Improved methodologies for the preparation of highly substituted pyridines.

    PubMed

    Fernández Sainz, Yolanda; Raw, Steven A; Taylor, Richard J K

    2005-11-25

    [reaction: see text] Two separate strategies have been developed for the preparation of highly substituted pyridines from 1,2,4-triazines via the inverse-electron-demand Diels-Alder reaction: a microwave-promoted, solvent-free procedure and a tethered imine-enamine (TIE) approach. Both routes avoid the need for a discrete aromatization step and offer significant advantages over the classical methods, giving a wide variety of tri-, tetra-, and penta-substituted pyridines in high, optimized yields.

  15. Graphene-based materials for flexible supercapacitors.

    PubMed

    Shao, Yuanlong; El-Kady, Maher F; Wang, Lisa J; Zhang, Qinghong; Li, Yaogang; Wang, Hongzhi; Mousavi, Mir F; Kaner, Richard B

    2015-06-07

    The demand for flexible/wearable electronic devices that have aesthetic appeal and multi-functionality has stimulated the rapid development of flexible supercapacitors with enhanced electrochemical performance and mechanical flexibility. After a brief introduction to flexible supercapacitors, we summarize current progress made with graphene-based electrodes. Two recently proposed prototypes for flexible supercapacitors, known as micro-supercapacitors and fiber-type supercapacitors, are then discussed. We also present our perspective on the development of graphene-based electrodes for flexible supercapacitors.

  16. Inverse electron demand Diels-Alder reactions in chemical biology.

    PubMed

    Oliveira, B L; Guo, Z; Bernardes, G J L

    2017-08-14

    The emerging inverse electron demand Diels-Alder (IEDDA) reaction stands out from other bioorthogonal reactions by virtue of its unmatchable kinetics, excellent orthogonality and biocompatibility. With the recent discovery of novel dienophiles and optimal tetrazine coupling partners, attention has now been turned to the use of IEDDA approaches in basic biology, imaging and therapeutics. Here we review this bioorthogonal reaction and its promising applications for live cell and animal studies. We first discuss the key factors that contribute to the fast IEDDA kinetics and describe the most recent advances in the synthesis of tetrazine and dienophile coupling partners. Both coupling partners have been incorporated into proteins for tracking and imaging by use of fluorogenic tetrazines that become strongly fluorescent upon reaction. Selected notable examples of such applications are presented. The exceptional fast kinetics of this catalyst-free reaction, even using low concentrations of coupling partners, make it amenable for in vivo radiolabelling using pretargeting methodologies, which are also discussed. Finally, IEDDA reactions have recently found use in bioorthogonal decaging to activate proteins or drugs in gain-of-function strategies. We conclude by showing applications of the IEDDA reaction in the construction of biomaterials that are used for drug delivery and multimodal imaging, among others. The use and utility of the IEDDA reaction is interdisciplinary and promises to revolutionize chemical biology, radiochemistry and materials science.

  17. A potent approach for the development of FPGA based DAQ system for HEP experiments

    NASA Astrophysics Data System (ADS)

    Khan, Shuaib Ahmad; Mitra, Jubin; David, Erno; Kiss, Tivadar; Nayak, Tapan Kumar

    2017-10-01

    With ever increasing particle beam energies and interaction rates in modern High Energy Physics (HEP) experiments in the present and future accelerator facilities, there has always been the demand for robust Data Acquisition (DAQ) schemes which perform in the harsh radiation environment and handle high data volume. The scheme is required to be flexible enough to adapt to the demands of future detector and electronics upgrades, and at the same time keeping the cost factor in mind. To address these challenges, in the present work, we discuss an efficient DAQ scheme for error resilient, high speed data communication on commercially available state-of-the-art FPGA with optical links. The scheme utilises GigaBit Transceiver (GBT) protocol to establish radiation tolerant communication link between on-detector front-end electronics situated in harsh radiation environment to the back-end Data Processing Unit (DPU) placed in a low radiation zone. The acquired data are reconstructed in DPU which reduces the data volume significantly, and then transmitted to the computing farms through high speed optical links using 10 Gigabit Ethernet (10GbE). In this study, we focus on implementation and testing of GBT protocol and 10GbE links on an Intel FPGA. Results of the measurements of resource utilisation, critical path delays, signal integrity, eye diagram and Bit Error Rate (BER) are presented, which are the indicators for efficient system performance.

  18. Analytical applications of microbial fuel cells. Part I: Biochemical oxygen demand.

    PubMed

    Abrevaya, Ximena C; Sacco, Natalia J; Bonetto, Maria C; Hilding-Ohlsson, Astrid; Cortón, Eduardo

    2015-01-15

    Microbial fuel cells (MFCs) are bio-electrochemical devices, where usually the anode (but sometimes the cathode, or both) contains microorganisms able to generate and sustain an electrochemical gradient which is used typically to generate electrical power. In the more studied set-up, the anode contains heterotrophic bacteria in anaerobic conditions, capable to oxidize organic molecules releasing protons and electrons, as well as other by-products. Released protons could reach the cathode (through a membrane or not) whereas electrons travel across an external circuit originating an easily measurable direct current flow. MFCs have been proposed fundamentally as electric power producing devices or more recently as hydrogen producing devices. Here we will review the still incipient development of analytical uses of MFCs or related devices or set-ups, in the light of a non-restrictive MFC definition, as promising tools to asset water quality or other measurable parameters. An introduction to biological based analytical methods, including bioassays and biosensors, as well as MFCs design and operating principles, will also be included. Besides, the use of MFCs as biochemical oxygen demand sensors (perhaps the main analytical application of MFCs) is discussed. In a companion review (Part 2), other new analytical applications are reviewed used for toxicity sensors, metabolic sensors, life detectors, and other proposed applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Laser-powered dielectric-structures for the production of high-brightness electron and x-ray beams

    NASA Astrophysics Data System (ADS)

    Travish, Gil; Yoder, Rodney B.

    2011-05-01

    Laser powered accelerators have been under intensive study for the past decade due to their promise of high gradients and leveraging of rapid technological progress in photonics. Of the various acceleration schemes under examination, those based on dielectric structures may enable the production of relativistic electron beams in breadbox sized systems. When combined with undulators having optical-wavelength periods, these systems could produce high brilliance x-rays which find application in, for instance, medical and industrial imaging. These beams also may open the way for table-top atto-second sciences. Development and testing of these dielectric structures faces a number of challenges including complex beam dynamics, new demands on lasers and optical coupling, beam injection schemes, and fabrication. We describe one approach being pursued at UCLA-the Micro Accelerator Platform (MAP). A structure similar to the MAP has also been designed which produces periodic deflections and acts as an undulator for radiation production, and the prospects for this device will be considered. The lessons learned from the multi-year effort to realize these devices will be presented. Challenges remain with acceleration of sub-relativistic beams, focusing, beam phase stability and extension of these devices to higher beam energies. Our progress in addressing these hurdles will be summarized. Finally, the demands on laser technology and optical coupling will be detailed.

  20. Fully kinetic 3D simulations of the Hermean magnetosphere under realistic conditions: a new approach

    NASA Astrophysics Data System (ADS)

    Amaya, Jorge; Gonzalez-Herrero, Diego; Lembège, Bertrand; Lapenta, Giovanni

    2017-04-01

    Simulations of the magnetosphere of planets are usually performed using the MHD and the hybrid approaches. However, these two methods still rely on approximations for the computation of the pressure tensor, and require the neutrality of the plasma at every point of the domain by construction. These approximations undermine the role of electrons on the emergence of plasma features in the magnetosphere of planets. The high mobility of electrons, their characteristic time and space scales, and the lack of perfect neutrality, are the source of many observed phenomena in the magnetospheres, including the turbulence energy cascade, the magnetic reconnection, the particle acceleration in the shock front and the formation of current systems around the magnetosphere. Fully kinetic codes are extremely demanding of computing time, and have been unable to perform simulations of the full magnetosphere at the real scales of a planet with realistic plasma conditions. This is caused by two main reasons: 1) explicit codes must resolve the electron scales limiting the time and space discretisation, and 2) current versions of semi-implicit codes are unstable for cell sizes larger than a few Debye lengths. In this work we present new simulations performed with ECsim, an Energy Conserving semi-implicit method [1], that can overcome these two barriers. We compare the solutions obtained with ECsim with the solutions obtained by the classic semi-implicit code iPic3D [2]. The new simulations with ECsim demand a larger computational effort, but the time and space discretisations are larger than those in iPic3D allowing for a faster simulation time of the full planetary environment. The new code, ECsim, can reach a resolution allowing the capture of significant large scale physics without loosing kinetic electron information, such as wave-electron interaction and non-Maxwellian electron velocity distributions [3]. The code is able to better capture the thickness of the different boundary layers of the magnetosphere of Mercury. Electron kinetics are consistent with the spatial and temporal scale resolutions. Simulations are compared with measurements from the MESSENGER spacecraft showing a better fit when compared against the classic fully kinetic code iPic3D. These results show that the new generation of Energy Conserving semi-implicit codes can be used for an accurate analysis and interpretation of particle data from magnetospheric missions like BepiColombo and MMS, including electron velocity distributions and electron temperature anisotropies. [1] Lapenta, G. (2016). Exactly Energy Conserving Implicit Moment Particle in Cell Formulation. arXiv preprint arXiv:1602.06326. [2] Markidis, S., & Lapenta, G. (2010). Multi-scale simulations of plasma with iPIC3D. Mathematics and Computers in Simulation, 80(7), 1509-1519. [3] Lapenta, G., Gonzalez-Herrero, D., & Boella, E. (2016). Multiple scale kinetic simulations with the energy conserving semi implicit particle in cell (PIC) method. arXiv preprint arXiv:1612.08289.

  1. MATLAB/Simulink Pulse-Echo Ultrasound System Simulator Based on Experimentally Validated Models.

    PubMed

    Kim, Taehoon; Shin, Sangmin; Lee, Hyongmin; Lee, Hyunsook; Kim, Heewon; Shin, Eunhee; Kim, Suhwan

    2016-02-01

    A flexible clinical ultrasound system must operate with different transducers, which have characteristic impulse responses and widely varying impedances. The impulse response determines the shape of the high-voltage pulse that is transmitted and the specifications of the front-end electronics that receive the echo; the impedance determines the specification of the matching network through which the transducer is connected. System-level optimization of these subsystems requires accurate modeling of pulse-echo (two-way) response, which in turn demands a unified simulation of the ultrasonics and electronics. In this paper, this is realized by combining MATLAB/Simulink models of the high-voltage transmitter, the transmission interface, the acoustic subsystem which includes wave propagation and reflection, the receiving interface, and the front-end receiver. To demonstrate the effectiveness of our simulator, the models are experimentally validated by comparing the simulation results with the measured data from a commercial ultrasound system. This simulator could be used to quickly provide system-level feedback for an optimized tuning of electronic design parameters.

  2. 3D inverse-opal structured Li4Ti5O12 Anode for fast Li-Ion storage capabilities

    NASA Astrophysics Data System (ADS)

    Kim, Dahye; Quang, Nguyen Duc; Hien, Truong Thi; Chinh, Nguyen Duc; Kim, Chunjoong; Kim, Dojin

    2017-11-01

    Since the demand for high power Li-ion batteries (LIBs) is increasing, spinel-structured lithium titanate, Li4Ti5O12 (LTO), as the anode material has attracted great attention because of its excellent cycle retention, good thermal stability, high rate capability, and so on. However, LTO shows relatively low conductivity due to empty 3 d orbital of Ti4+ state. Nanoscale architectures can shorten electron conduction path, thus such low electronic conductivity can be overcome while Li+ can be easily accessed due to large surface area. Herein, three dimensional bicontinuous LTO electrodes were prepared via close-packed self-assembly with polystyrene (PS) spheres followed by removal of them, which leads to no blockage of Li+ ion transportation pathways as well as fast electron conduction. 3D bicontinuous LTO electrodes showed high-rate lithium storage capability (103 mAh/g at 20 C), which is promising as the power sources that require rapid electrochemical response.[Figure not available: see fulltext.

  3. Advanced Graphene-Based Binder-Free Electrodes for High-Performance Energy Storage.

    PubMed

    Ji, Junyi; Li, Yang; Peng, Wenchao; Zhang, Guoliang; Zhang, Fengbao; Fan, Xiaobin

    2015-09-23

    The increasing demand for energy has triggered tremendous research effort for the development of high-performance and durable energy-storage devices. Advanced graphene-based electrodes with high electrical conductivity and ion accessibility can exhibit superior electrochemical performance in energy-storage devices. Among them, binder-free configurations can enhance the electron conductivity of the electrode, which leads to a higher capacity by avoiding the addition of non-conductive and inactive binders. Graphene, a 2D material, can be fabricated into a porous and flexible structure with an interconnected conductive network. Such a conductive structure is favorable for both electron and ion transport to the entire electrode surface. In this review, the main processes used to prepare binder-free graphene-based hybrids with high porosity and well-designed electron conductive networks are summarized. Then, the applications of free-standing binder-free graphene-based electrodes in energy-storage devices are discussed. Future research aspects with regard to overcoming the technological bottlenecks are also proposed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Oxide Heteroepitaxy for Flexible Optoelectronics.

    PubMed

    Bitla, Yugandhar; Chen, Ching; Lee, Hsien-Chang; Do, Thi Hien; Ma, Chun-Hao; Qui, Le Van; Huang, Chun-Wei; Wu, Wen-Wei; Chang, Li; Chiu, Po-Wen; Chu, Ying-Hao

    2016-11-30

    The emerging technological demands for flexible and transparent electronic devices have compelled researchers to look beyond the current silicon-based electronics. However, fabrication of devices on conventional flexible substrates with superior performance are constrained by the trade-off between processing temperature and device performance. Here, we propose an alternative strategy to circumvent this issue via the heteroepitaxial growth of transparent conducting oxides (TCO) on the flexible mica substrate with performance comparable to that of their rigid counterparts. With the examples of ITO and AZO as a case study, a strong emphasis is laid upon the growth of flexible yet epitaxial TCO relying muscovite's superior properties compared to those of conventional flexible substrates and its compatibility with the present fabrication methods. Besides excellent optoelectro-mechanical properties, an additional functionality of high-temperature stability, normally lacking in the current state-of-the-art transparent flexitronics, is provided by these heterostructures. These epitaxial TCO electrodes with good chemical and thermal stabilities as well as mechanical durability can significantly contribute to the field of flexible, light-weight, and portable smart electronics.

  5. Simulations of Coherent Synchrotron Radiation Effects in Electron Machines

    NASA Astrophysics Data System (ADS)

    Migliorati, M.; Schiavi, A.; Dattoli, G.

    2007-09-01

    Coherent synchrotron radiation (CSR) generated by high intensity electron beams can be a source of undesirable effects limiting the performance of storage rings. The complexity of the physical mechanisms underlying the interplay between the electron beam and the CSR demands for reliable simulation codes. In the past, codes based on Lie algebraic techniques have been very efficient to treat transport problems in accelerators. The extension of these methods to the non linear case is ideally suited to treat wakefields - beam interaction. In this paper we report on the development of a numerical code, based on the solution of the Vlasov equation, which includes the non linear contribution due to wakefields. The proposed solution method exploits an algebraic technique that uses the exponential operators. We show that, in the case of CSR wakefields, the integration procedure is capable of reproducing the onset of an instability which leads to microbunching of the beam thus increasing the CSR at short wavelengths. In addition, considerations on the threshold of the instability for Gaussian bunches is also reported.

  6. Simulations of Coherent Synchrotron Radiation Effects in Electron Machines

    NASA Astrophysics Data System (ADS)

    Migliorati, M.; Schiavi, A.; Dattoli, G.

    Coherent synchrotron radiation (CSR) generated by high intensity electron beams can be a source of undesirable effects limiting the performance of storage rings. The complexity of the physical mechanisms underlying the interplay between the electron beam and the CSR demands for reliable simulation codes. In the past, codes based on Lie algebraic techniques have been very efficient to treat transport problems in accelerators. The extension of these methods to the non linear case is ideally suited to treat wakefields - beam interaction. In this paper we report on the development of a numerical code, based on the solution of the Vlasov equation, which includes the non linear contribution due to wakefields. The proposed solution method exploits an algebraic technique that uses the exponential operators. We show that, in the case of CSR wakefields, the integration procedure is capable of reproducing the onset of an instability which leads to microbunching of the beam thus increasing the CSR at short wavelengths. In addition, considerations on the threshold of the instability for Gaussian bunches is also reported.

  7. Hydrotrifluoromethylation and iodotrifluoromethylation of alkenes and alkynes using an inorganic electride as a radical generator.

    PubMed

    Choi, Sungkyu; Kim, Ye Ji; Kim, Sun Min; Yang, Jung Woon; Kim, Sung Wng; Cho, Eun Jin

    2014-09-12

    The trifluoromethyl (CF3) group is a staple synthon that can alter the physical and chemical properties of organic molecules. Despite recent advances in trifluoromethylation methods, the development of a general synthetic methodology for efficient and selective trifluoromethylation remains an ongoing challenge motivated by a steadily increasing demand from the pharmaceutical, agrochemical and materials science industries. In this article, we describe a simple, efficient and environmentally benign strategy for the hydrotrifluoromethylation of unactivated alkenes and alkynes through a radical-mediated reaction using an inorganic electride, [Ca2N](+) · e(-), as the electron source. In the transformation, anionic electrons are transferred from [Ca2N](+) · e(-) electrides to the trifluoromethylating reagent CF3I to initiate radical-mediated trifluoromethylation. The role of ethanol is pivotal in the transformation, acting as the solvent, an electron-releasing promoter and a hydrogen atom source. In addition, iodotrifluoromethylation of alkynes proceeds selectively upon the control of electride amount.

  8. Architecture of a general purpose embedded Slow-Control Adapter ASIC for future high-energy physics experiments

    NASA Astrophysics Data System (ADS)

    Gabrielli, Alessandro; Loddo, Flavio; Ranieri, Antonio; De Robertis, Giuseppe

    2008-10-01

    This work is aimed at defining the architecture of a new digital ASIC, namely Slow-Control Adapter (SCA), which will be designed in a commercial 130-nm CMOS technology. This chip will be embedded within a high-speed data acquisition optical link (GBT) to control and monitor the front-end electronics in future high-energy physics experiments. The GBT link provides a transparent transport layer between the SCA and control electronics in the counting room. The proposed SCA supports a variety of common bus protocols to interface with end-user general-purpose electronics. Between the GBT and the SCA a standard 100 Mb/s IEEE-802.3 compatible protocol will be implemented. This standard protocol allows off-line tests of the prototypes using commercial components that support the same standard. The project is justified because embedded applications in modern large HEP experiments require particular care to assure the lowest possible power consumption, still offering the highest reliability demanded by very large particle detectors.

  9. The origin of the ligand-controlled regioselectivity in Rh-catalyzed [(2 + 2) + 2] carbocyclizations: steric vs. stereoelectronic effects† †Electronic supplementary information (ESI) available: Computational details, Cartesian coordinates and vibrational frequencies of all optimized structures. See DOI: 10.1039/c5sc02307f Click here for additional data file.

    PubMed Central

    Crandell, Douglas W.; Mazumder, Shivnath

    2015-01-01

    Density functional theory calculations demonstrate that the reversal of regiochemical outcome of the addition for substituted methyl propiolates in the rhodium-catalyzed [(2 + 2) + 2] carbocyclization with PPh3 and (S)-xyl-binap as ligands is both electronically and sterically controlled. For example, the ester functionality polarizes the alkyne π* orbital to favor overlap of the methyl-substituted terminus of the alkyne with the pπ-orbital of the alkenyl fragment of the rhodacycle during alkyne insertion with PPh3 as the ligand. In contrast, the sterically demanding xyl-binap ligand cannot accommodate the analogous alkyne orientation, thereby forcing insertion to occur at the sterically preferred ester terminus, overriding the electronically preferred orientation for alkyne insertion. PMID:28757978

  10. Solution-processable ambipolar diketopyrrolopyrrole-selenophene polymer with unprecedentedly high hole and electron mobilities.

    PubMed

    Lee, Junghoon; Han, A-Reum; Kim, Jonggi; Kim, Yiho; Oh, Joon Hak; Yang, Changduk

    2012-12-26

    There is a fast-growing demand for polymer-based ambipolar thin-film transistors (TFTs), in which both n-type and p-type transistor operations are realized in a single layer, while maintaining simplicity in processing. Research progress toward this end is essentially fueled by molecular engineering of the conjugated backbones of the polymers and the development of process architectures for device fabrication, which has recently led to hole and electron mobilities of more than 1.0 cm(2) V(-1) s(-1). However, ambipolar polymers with even higher performance are still required. By taking into account both the conjugated backbone and side chains of the polymer component, we have developed a dithienyl-diketopyrrolopyrrole (TDPP) and selenophene containing polymer with hybrid siloxane-solubilizing groups (PTDPPSe-Si). A synergistic combination of rational polymer backbone design, side-chain dynamics, and solution processing affords an enormous boost in ambipolar TFT performance, resulting in unprecedentedly high hole and electron mobilities of 3.97 and 2.20 cm(2) V(-1) s(-1), respectively.

  11. Validity of Basic Electronic 1 Module Integrated Character Value Based on Conceptual Change Teaching Model to Increase Students Physics Competency in STKIP PGRI West Sumatera

    NASA Astrophysics Data System (ADS)

    Hidayati, A.; Rahmi, A.; Yohandri; Ratnawulan

    2018-04-01

    The importance of teaching materials in accordance with the characteristics of students became the main reason for the development of basic electronics I module integrated character values based on conceptual change teaching model. The module development in this research follows the development procedure of Plomp which includes preliminary research, prototyping phase and assessment phase. In the first year of this research, the module is validated. Content validity is seen from the conformity of the module with the development theory in accordance with the demands of learning model characteristics. The validity of the construct is seen from the linkage and consistency of each module component developed with the characteristic of the integrated learning model of character values obtained through validator assessment. The average validation value assessed by the validator belongs to a very valid category. Based on the validator assessment then revised the basic electronics I module integrated character values based on conceptual change teaching model.

  12. Design of Architectures and Materials in In-Plane Micro-supercapacitors: Current Status and Future Challenges.

    PubMed

    Qi, Dianpeng; Liu, Yan; Liu, Zhiyuan; Zhang, Li; Chen, Xiaodong

    2017-02-01

    The rapid development of integrated electronics and the boom in miniaturized and portable devices have increased the demand for miniaturized and on-chip energy storage units. Currently thin-film batteries or microsized batteries are commercially available for miniaturized devices. However, they still suffer from several limitations, such as short lifetime, low power density, and complex architecture, which limit their integration. Supercapacitors can surmount all these limitations. Particularly for micro-supercapacitors with planar architectures, due to their unique design of the in-plane electrode finger arrays, they possess the merits of easy fabrication and integration into on-chip miniaturized electronics. Here, the focus is on the different strategies to design electrode finger arrays and the material engineering of in-plane micro-supercapacitors. It is expected that the advances in micro-supercapacitors with in-plane architectures will offer new opportunities for the miniaturization and integration of energy-storage units for portable devices and on-chip electronics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Wearable salivary uric acid mouthguard biosensor with integrated wireless electronics.

    PubMed

    Kim, Jayoung; Imani, Somayeh; de Araujo, William R; Warchall, Julian; Valdés-Ramírez, Gabriela; Paixão, Thiago R L C; Mercier, Patrick P; Wang, Joseph

    2015-12-15

    This article demonstrates an instrumented mouthguard capable of non-invasively monitoring salivary uric acid (SUA) levels. The enzyme (uricase)-modified screen printed electrode system has been integrated onto a mouthguard platform along with anatomically-miniaturized instrumentation electronics featuring a potentiostat, microcontroller, and a Bluetooth Low Energy (BLE) transceiver. Unlike RFID-based biosensing systems, which require large proximal power sources, the developed platform enables real-time wireless transmission of the sensed information to standard smartphones, laptops, and other consumer electronics for on-demand processing, diagnostics, or storage. The mouthguard biosensor system offers high sensitivity, selectivity, and stability towards uric acid detection in human saliva, covering the concentration ranges for both healthy people and hyperuricemia patients. The new wireless mouthguard biosensor system is able to monitor SUA level in real-time and continuous fashion, and can be readily expanded to an array of sensors for different analytes to enable an attractive wearable monitoring system for diverse health and fitness applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Networked information: Management issues for the acquisitions librarian

    NASA Technical Reports Server (NTRS)

    Lawrence, Gregory

    1994-01-01

    Historically, libraries have been the depositories and public access points to both domestic and international government information. A change in the information seeking behavior of the public is driving a change in government information publishing and dissemination. Patrons who traditionally used libraries for access to printed government information have become familiar and comfortable with the electronic environment. These data users are showing an increased interest in certain types of government information in electronic format, including indexes, numeric files, statistics, and hypertext documents. Government response to increased demand for electronic information has led to a flurry of special initiatives, with the production of information products on diskette, CD-ROM, and dissemination via the Internet. Libraries, and acquisitions units in particular, are being challenged to provide consistent and timely management of the information. The rapidly developing communications infrastructure, which frequently redesigns access to the information environment, poses significant obstacles to, and the tremendous opportunities for, making large bodies of government information available to a broad base of users.

  15. Wearable salivary uric acid mouthguard biosensor with integrated wireless electronics

    PubMed Central

    Kim, Jayoung; Imani, Somayeh; de Araujo, William R.; Warchall, Julian; Valdés-Ramírez, Gabriela; Paixão, Thiago R.L.C.; Mercier, Patrick P.; Wang, Joseph

    2016-01-01

    This article demonstrates an instrumented mouthguard capable of non-invasively monitoring salivary uric acid (SUA) levels. The enzyme (uricase)-modified screen printed electrode system has been integrated onto a mouthguard platform along with anatomically-miniaturized instrumentation electronics featuring a potentiostat, microcontroller, and a Bluetooth Low Energy (BLE) transceiver. Unlike RFID-based biosensing systems, which require large proximal power sources, the developed platform enables real-time wireless transmission of the sensed information to standard smartphones, laptops, and other consumer electronics for on-demand processing, diagnostics, or storage. The mouthguard biosensor system offers high sensitivity, selectivity, and stability towards uric acid detection in human saliva, covering the concentration ranges for both healthy people and hyperuricemia patients. The new wireless mouthguard biosensor system is able to monitor SUA level in real-time and continuous fashion, and can be readily expanded to an array of sensors for different analytes to enable an attractive wearable monitoring system for diverse health and fitness applications. PMID:26276541

  16. Flexible Sensing Electronics for Wearable/Attachable Health Monitoring.

    PubMed

    Wang, Xuewen; Liu, Zheng; Zhang, Ting

    2017-07-01

    Wearable or attachable health monitoring smart systems are considered to be the next generation of personal portable devices for remote medicine practices. Smart flexible sensing electronics are components crucial in endowing health monitoring systems with the capability of real-time tracking of physiological signals. These signals are closely associated with body conditions, such as heart rate, wrist pulse, body temperature, blood/intraocular pressure and blood/sweat bio-information. Monitoring such physiological signals provides a convenient and non-invasive way for disease diagnoses and health assessments. This Review summarizes the recent progress of flexible sensing electronics for their use in wearable/attachable health monitoring systems. Meanwhile, we present an overview of different materials and configurations for flexible sensors, including piezo-resistive, piezo-electrical, capacitive, and field effect transistor based devices, and analyze the working principles in monitoring physiological signals. In addition, the future perspectives of wearable healthcare systems and the technical demands on their commercialization are briefly discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Architectural Choices and Challenges of Integrating Electronic Patient Questionnaires into the Electronic Medical Record to Support Patient-Centered Care

    PubMed Central

    Moore, Barbara J; Gaehde, Stephan; Curtis, Clayton

    2008-01-01

    Strategies to deliver guideline-concordant, patient-centered care during office visits sometimes impose conflicting demands on clinicians. One way to help relieve time-constrained visits and to improve the patient-centeredness of care may be through patients electronically self-reporting data that flow automatically into an EMR note for clinician confirmation or editing, relieving physicians of some data entry and rote history-gathering tasks, thus freeing up time to allow clinicians to focus on significant issues and patient concerns while also increasing the likelihood that necessary data are gathered and available for decision-making. We developed a prototype to enable such data gathering and integration into the EMR. The lack of consistent provision of interfaces by vendors for sending data into EMRs and the idiosyncrasies of any particular EMR in the context of a particular organization’s IT infrastructure and policies pose architectural choices and challenges that healthcare organizations embarking on such IT projects may need to consider. PMID:18999024

  18. Implications of Electronic Commerce for Fiscal Policy

    NASA Astrophysics Data System (ADS)

    Goolsbee, Austan

    In this chapter, I will consider both sides of the relationship between electronic commerce and fiscal policy. For the impact of electronic commerce on fiscal policy, I will pay particular attention to the potential sales-tax revenue losses. The data suggest that the potential losses are actually modest over the next several years. I will also consider the reverse relationship - how fiscal policy affects Internet commerce. Here the evidence suggests that taxes have a sizable effect. I point out, though, that this only supports special treatment if there is some positive externality. Without one, the tax system will lead to excessive online buying to avoid taxes. I will then deal the neglected issue of taxes and Internet access, which can create large deadweight costs both because demand may be price-sensitive and because taxes can slow the spread of new technologies. Finally, I offer some discussion of the international context of taxes and the Internet and the international temptations to raise rates on E-commerce.

  19. Progress Towards High-Sensitivity Arrays of Detectors of Sub-mm Radiation using Superconducting Tunnel Junctions with Radio-Frequency Single-Electron Transistors

    NASA Technical Reports Server (NTRS)

    Stevenson, T. R.; Hsieh, W.-T.; Li, M. J.; Stahle, C. M.; Wollack, E. J.; Schoelkopf, R. J.; Krebs, Carolyn (Technical Monitor)

    2002-01-01

    The science drivers for the SPIRIT/SPECS missions demand sensitive, fast, compact, low-power, large-format detector arrays for high resolution imaging and spectroscopy in the far infrared and submillimeter. Detector arrays with 10,000 pixels and sensitivity less than 10(exp 20)-20 W/Hz(exp 20)0.5 are needed. Antenna-coupled superconducting tunnel junction detectors with integrated rf single-electron transistor readout amplifiers have the potential for achieving this high level of sensitivity, and can take advantage of an rf multiplexing technique when forming arrays. The device consists of an antenna structure to couple radiation into a small superconducting volume and cause quasiparticle excitations, and a single-electron transistor to measure currents through tunnel junction contacts to the absorber volume. We will describe optimization of device parameters, and recent results on fabrication techniques for producing devices with high yield for detector arrays. We will also present modeling of expected saturation power levels, antenna coupling, and rf multiplexing schemes.

  20. Rational material design for ultrafast rechargeable lithium-ion batteries.

    PubMed

    Tang, Yuxin; Zhang, Yanyan; Li, Wenlong; Ma, Bing; Chen, Xiaodong

    2015-10-07

    Rechargeable lithium-ion batteries (LIBs) are important electrochemical energy storage devices for consumer electronics and emerging electrical/hybrid vehicles. However, one of the formidable challenges is to develop ultrafast charging LIBs with the rate capability at least one order of magnitude (>10 C) higher than that of the currently commercialized LIBs. This tutorial review presents the state-of-the-art developments in ultrafast charging LIBs by the rational design of materials. First of all, fundamental electrochemistry and related ionic/electronic conduction theories identify that the rate capability of LIBs is kinetically limited by the sluggish solid-state diffusion process in electrode materials. Then, several aspects of the intrinsic materials, materials engineering and processing, and electrode materials architecture design towards maximizing both ionic and electronic conductivity in the electrode with a short diffusion length are deliberated. Finally, the future trends and perspectives for the ultrafast rechargeable LIBs are discussed. Continuous rapid progress in this area is essential and urgent to endow LIBs with ultrafast charging capability to meet huge demands in the near future.

  1. Oxide Thermoelectric Materials: A Structure-Property Relationship

    NASA Astrophysics Data System (ADS)

    Nag, Abanti; Shubha, V.

    2014-04-01

    Recent demand for thermoelectric materials for power harvesting from automobile and industrial waste heat requires oxide materials because of their potential advantages over intermetallic alloys in terms of chemical and thermal stability at high temperatures. Achievement of thermoelectric figure of merit equivalent to unity ( ZT ≈ 1) for transition-metal oxides necessitates a second look at the fundamental theory on the basis of the structure-property relationship giving rise to electron correlation accompanied by spin fluctuation. Promising transition-metal oxides based on wide-bandgap semiconductors, perovskite and layered oxides have been studied as potential candidate n- and p-type materials. This paper reviews the correlation between the crystal structure and thermoelectric properties of transition-metal oxides. The crystal-site-dependent electronic configuration and spin degeneracy to control the thermopower and electron-phonon interaction leading to polaron hopping to control electrical conductivity is discussed. Crystal structure tailoring leading to phonon scattering at interfaces and nanograin domains to achieve low thermal conductivity is also highlighted.

  2. Effects of electron beam irradiation and temperature on the treatment of swine wastewater using an ion exchange biological reactor.

    PubMed

    Lim, Seung Joo; Kim, Tak-Hyun; Lee, Sang-hun; Kim, Jun-young; Kim, Sun-kyoung

    2013-06-01

    Swine wastewater was treated using an ion exchange biological reactor (IEBR). Organic matter and nutrient in swine wastewater were pre-treated by electron beam irradiation. The optimal dose for solubilization of organic matter in swine wastewater ranged from 20 kGy to 75 kGy. The carbohydrates, proteins, and lipids were investigated as proteins and lipids mainly contained the solubilized organic matter. The solubilization of organic matter in swine wastewater was affected by the combination effects of temperature and dose. The maximum chemical oxygen demand (COD) and ammonia removal efficiencies were 74.4% and 76.7% at a dose of 0 kGy under room temperatures (23.0°C). The removal of ammonia was significantly affected by low temperature (15.3°C). On the other hand, the removal of phosphorus was not a function of electron beam irradiation or temperature because struvite is one of the main removal mechanisms under anoxic conditions. Published by Elsevier Ltd.

  3. Ultrathin, transferred layers of thermally grown silicon dioxide as biofluid barriers for biointegrated flexible electronic systems.

    PubMed

    Fang, Hui; Zhao, Jianing; Yu, Ki Jun; Song, Enming; Farimani, Amir Barati; Chiang, Chia-Han; Jin, Xin; Xue, Yeguang; Xu, Dong; Du, Wenbo; Seo, Kyung Jin; Zhong, Yiding; Yang, Zijian; Won, Sang Min; Fang, Guanhua; Choi, Seo Woo; Chaudhuri, Santanu; Huang, Yonggang; Alam, Muhammad Ashraful; Viventi, Jonathan; Aluru, N R; Rogers, John A

    2016-10-18

    Materials that can serve as long-lived barriers to biofluids are essential to the development of any type of chronic electronic implant. Devices such as cardiac pacemakers and cochlear implants use bulk metal or ceramic packages as hermetic enclosures for the electronics. Emerging classes of flexible, biointegrated electronic systems demand similar levels of isolation from biofluids but with thin, compliant films that can simultaneously serve as biointerfaces for sensing and/or actuation while in contact with the soft, curved, and moving surfaces of target organs. This paper introduces a solution to this materials challenge that combines (i) ultrathin, pristine layers of silicon dioxide (SiO 2 ) thermally grown on device-grade silicon wafers, and (ii) processing schemes that allow integration of these materials onto flexible electronic platforms. Accelerated lifetime tests suggest robust barrier characteristics on timescales that approach 70 y, in layers that are sufficiently thin (less than 1 μm) to avoid significant compromises in mechanical flexibility or in electrical interface fidelity. Detailed studies of temperature- and thickness-dependent electrical and physical properties reveal the key characteristics. Molecular simulations highlight essential aspects of the chemistry that governs interactions between the SiO 2 and surrounding water. Examples of use with passive and active components in high-performance flexible electronic devices suggest broad utility in advanced chronic implants.

  4. Microbial fuel cell operation using monoazo and diazo dyes as terminal electron acceptor for simultaneous decolourisation and bioelectricity generation.

    PubMed

    Oon, Yoong-Sin; Ong, Soon-An; Ho, Li-Ngee; Wong, Yee-Shian; Oon, Yoong-Ling; Lehl, Harvinder Kaur; Thung, Wei-Eng; Nordin, Noradiba

    2017-03-05

    Monoazo and diazo dyes [New coccine (NC), Acid orange 7 (AO7), Reactive red 120 (RR120) and Reactive green 19 (RG19)] were employed as electron acceptors in the abiotic cathode of microbial fuel cell. The electrons and protons generated from microbial organic oxidation at the anode which were utilized for electrochemical azo dye reduction at the cathodic chamber was successfully demonstrated. When NC was employed as the electron acceptor, the chemical oxygen demand (COD) removal and dye decolourisation efficiencies obtained at the anodic and cathodic chamber were 73±3% and 95.1±1.1%, respectively. This study demonstrated that the decolourisation rates of monoazo dyes were ∼50% higher than diazo dyes. The maximum power density in relation to NC decolourisation was 20.64mW/m 2 , corresponding to current density of 120.24mA/m 2 . The decolourisation rate and power output of different azo dyes were in the order of NC>AO7>RR120>RG19. The findings revealed that the structure of dye influenced the decolourisation and power performance of MFC. Azo dye with electron-withdrawing group at para substituent to azo bond would draw electrons from azo bond; hence the azo dye became more electrophilic and more favourable for dye reduction. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Ultrathin, transferred layers of thermally grown silicon dioxide as biofluid barriers for biointegrated flexible electronic systems

    PubMed Central

    Fang, Hui; Yu, Ki Jun; Song, Enming; Farimani, Amir Barati; Chiang, Chia-Han; Jin, Xin; Xu, Dong; Du, Wenbo; Seo, Kyung Jin; Zhong, Yiding; Yang, Zijian; Won, Sang Min; Fang, Guanhua; Choi, Seo Woo; Chaudhuri, Santanu; Huang, Yonggang; Alam, Muhammad Ashraful; Viventi, Jonathan; Aluru, N. R.; Rogers, John A.

    2016-01-01

    Materials that can serve as long-lived barriers to biofluids are essential to the development of any type of chronic electronic implant. Devices such as cardiac pacemakers and cochlear implants use bulk metal or ceramic packages as hermetic enclosures for the electronics. Emerging classes of flexible, biointegrated electronic systems demand similar levels of isolation from biofluids but with thin, compliant films that can simultaneously serve as biointerfaces for sensing and/or actuation while in contact with the soft, curved, and moving surfaces of target organs. This paper introduces a solution to this materials challenge that combines (i) ultrathin, pristine layers of silicon dioxide (SiO2) thermally grown on device-grade silicon wafers, and (ii) processing schemes that allow integration of these materials onto flexible electronic platforms. Accelerated lifetime tests suggest robust barrier characteristics on timescales that approach 70 y, in layers that are sufficiently thin (less than 1 μm) to avoid significant compromises in mechanical flexibility or in electrical interface fidelity. Detailed studies of temperature- and thickness-dependent electrical and physical properties reveal the key characteristics. Molecular simulations highlight essential aspects of the chemistry that governs interactions between the SiO2 and surrounding water. Examples of use with passive and active components in high-performance flexible electronic devices suggest broad utility in advanced chronic implants. PMID:27791052

  6. MCNP6.1 simulations for low-energy atomic relaxation: Code-to-code comparison with GATEv7.2, PENELOPE2014, and EGSnrc

    NASA Astrophysics Data System (ADS)

    Jung, Seongmoon; Sung, Wonmo; Lee, Jaegi; Ye, Sung-Joon

    2018-01-01

    Emerging radiological applications of gold nanoparticles demand low-energy electron/photon transport calculations including details of an atomic relaxation process. Recently, MCNP® version 6.1 (MCNP6.1) has been released with extended cross-sections for low-energy electron/photon, subshell photoelectric cross-sections, and more detailed atomic relaxation data than the previous versions. With this new feature, the atomic relaxation process of MCNP6.1 has not been fully tested yet with its new physics library (eprdata12) that is based on the Evaluated Atomic Data Library (EADL). In this study, MCNP6.1 was compared with GATEv7.2, PENELOPE2014, and EGSnrc that have been often used to simulate low-energy atomic relaxation processes. The simulations were performed to acquire both photon and electron spectra produced by interactions of 15 keV electrons or photons with a 10-nm-thick gold nano-slab. The photon-induced fluorescence X-rays from MCNP6.1 fairly agreed with those from GATEv7.2 and PENELOPE2014, while the electron-induced fluorescence X-rays of the four codes showed more or less discrepancies. A coincidence was observed in the photon-induced Auger electrons simulated by MCNP6.1 and GATEv7.2. A recent release of MCNP6.1 with eprdata12 can be used to simulate the photon-induced atomic relaxation.

  7. Correction of image drift and distortion in a scanning electron microscopy.

    PubMed

    Jin, P; Li, X

    2015-12-01

    Continuous research on small-scale mechanical structures and systems has attracted strong demand for ultrafine deformation and strain measurements. Conventional optical microscope cannot meet such requirements owing to its lower spatial resolution. Therefore, high-resolution scanning electron microscope has become the preferred system for high spatial resolution imaging and measurements. However, scanning electron microscope usually is contaminated by distortion and drift aberrations which cause serious errors to precise imaging and measurements of tiny structures. This paper develops a new method to correct drift and distortion aberrations of scanning electron microscope images, and evaluates the effect of correction by comparing corrected images with scanning electron microscope image of a standard sample. The drift correction is based on the interpolation scheme, where a series of images are captured at one location of the sample and perform image correlation between the first image and the consequent images to interpolate the drift-time relationship of scanning electron microscope images. The distortion correction employs the axial symmetry model of charged particle imaging theory to two images sharing with the same location of one object under different imaging fields of view. The difference apart from rigid displacement between the mentioned two images will give distortion parameters. Three-order precision is considered in the model and experiment shows that one pixel maximum correction is obtained for the employed high-resolution electron microscopic system. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  8. Beam by design: Laser manipulation of electrons in modern accelerators

    NASA Astrophysics Data System (ADS)

    Hemsing, Erik; Stupakov, Gennady; Xiang, Dao; Zholents, Alexander

    2014-07-01

    Accelerator-based light sources such as storage rings and free-electron lasers use relativistic electron beams to produce intense radiation over a wide spectral range for fundamental research in physics, chemistry, materials science, biology, and medicine. More than a dozen such sources operate worldwide, and new sources are being built to deliver radiation that meets with the ever-increasing sophistication and depth of new research. Even so, conventional accelerator techniques often cannot keep pace with new demands and, thus, new approaches continue to emerge. In this article, a variety of recently developed and promising techniques that rely on lasers to manipulate and rearrange the electron distribution in order to tailor the properties of the radiation are reviewed. Basic theories of electron-laser interactions, techniques to create microstructures and nanostructures in electron beams, and techniques to produce radiation with customizable waveforms are reviewed. An overview of laser-based techniques for the generation of fully coherent x rays, mode-locked x-ray pulse trains, light with orbital angular momentum, and attosecond or even zeptosecond long coherent pulses in free-electron lasers is presented. Several methods to generate femtosecond pulses in storage rings are also discussed. Additionally, various schemes designed to enhance the performance of light sources through precision beam preparation including beam conditioning, laser heating, emittance exchange, and various laser-based diagnostics are described. Together these techniques represent a new emerging concept of "beam by design" in modern accelerators, which is the primary focus of this article.

  9. Real-Time Digital Signal Processing Based on FPGAs for Electronic Skin Implementation †

    PubMed Central

    Ibrahim, Ali; Gastaldo, Paolo; Chible, Hussein; Valle, Maurizio

    2017-01-01

    Enabling touch-sensing capability would help appliances understand interaction behaviors with their surroundings. Many recent studies are focusing on the development of electronic skin because of its necessity in various application domains, namely autonomous artificial intelligence (e.g., robots), biomedical instrumentation, and replacement prosthetic devices. An essential task of the electronic skin system is to locally process the tactile data and send structured information either to mimic human skin or to respond to the application demands. The electronic skin must be fabricated together with an embedded electronic system which has the role of acquiring the tactile data, processing, and extracting structured information. On the other hand, processing tactile data requires efficient methods to extract meaningful information from raw sensor data. Machine learning represents an effective method for data analysis in many domains: it has recently demonstrated its effectiveness in processing tactile sensor data. In this framework, this paper presents the implementation of digital signal processing based on FPGAs for tactile data processing. It provides the implementation of a tensorial kernel function for a machine learning approach. Implementation results are assessed by highlighting the FPGA resource utilization and power consumption. Results demonstrate the feasibility of the proposed implementation when real-time classification of input touch modalities are targeted. PMID:28287448

  10. Real-Time Digital Signal Processing Based on FPGAs for Electronic Skin Implementation.

    PubMed

    Ibrahim, Ali; Gastaldo, Paolo; Chible, Hussein; Valle, Maurizio

    2017-03-10

    Enabling touch-sensing capability would help appliances understand interaction behaviors with their surroundings. Many recent studies are focusing on the development of electronic skin because of its necessity in various application domains, namely autonomous artificial intelligence (e.g., robots), biomedical instrumentation, and replacement prosthetic devices. An essential task of the electronic skin system is to locally process the tactile data and send structured information either to mimic human skin or to respond to the application demands. The electronic skin must be fabricated together with an embedded electronic system which has the role of acquiring the tactile data, processing, and extracting structured information. On the other hand, processing tactile data requires efficient methods to extract meaningful information from raw sensor data. Machine learning represents an effective method for data analysis in many domains: it has recently demonstrated its effectiveness in processing tactile sensor data. In this framework, this paper presents the implementation of digital signal processing based on FPGAs for tactile data processing. It provides the implementation of a tensorial kernel function for a machine learning approach. Implementation results are assessed by highlighting the FPGA resource utilization and power consumption. Results demonstrate the feasibility of the proposed implementation when real-time classification of input touch modalities are targeted.

  11. Social relationships among adolescents as described in an electronic diary: a mixed methods study.

    PubMed

    Anttila, Katriina I; Anttila, Minna J; Kurki, Marjo H; Välimäki, Maritta A

    2017-01-01

    Social relationships among adolescents with mental disorders are demanding. Adolescents with depressive symptoms may have few relationships and have difficulties sharing their problems. Internet may offer reliable and easy to use tool to collect real-time information from adolescents. The aim of this study is to explore how adolescents describe their social relationships with an electronic diary. Mixed methods were used to obtain a broad picture of adolescents' social relationships with the data gathered from network maps and reflective texts written in an electronic diary. Adolescents who visited an outpatient clinic and used an intervention (N=70) designed for adolescents with signs of depression were invited to use the electronic diary; 29 did so. The quantitative data gathered in the electronic diary were summarized with descriptive statistics, and the qualitative data were categorized using a thematic analysis with an inductive approach. We found that social relationships among adolescents with signs of depression can vary greatly in regards to the number of existing relationships (from lacking to 21) and the quality of the relationships (from trustful to difficult). However, the relationships may change, and the adolescents are also willing to build up their social relationships. Professionals need to be aware of the diversity of adolescents' social relationships and their need for personalized support.

  12. [Qualitative analysis among electronic cigarette users: practices, use, representations].

    PubMed

    Fontaine, Astrid; Artigas, Fernanda

    2017-01-01

    Electronic cigarettes are smokeless devices that simulate the act of tobacco smoking by spraying an ?e-liquid? and diffusing an aerosol that is inhaled by the user. Although the initial enthusiasm observed in 2012-2013 has tended to flag, electronic cigarettes are now part of the landscape of smokers seeking an alternative to smoking and abstinence. Smoking cessation professionals need to meet a growing demand from smokers and must adopt a clear position in relation to this device. The results presented here were derived from a qualitative study conducted with the financial support of the French Directorate of Health, part of the Ministry of Social Affairs and Health from September 2014 to January 2016. The study was based on classical field-work ethnology: observations were made during events involving electronic cigarette users and 25 semi-structured interviews with diverse profiles to clarify a poorly known field. This study contributes to the observation and understanding of an emerging phenomenon, likely to induce a lasting change in our relationship to tobacco. The study revealed a wide variety of profiles among smokers interested by electronic cigarettes. Men and women, young and old, or former smokers, adopt various attitudes when trying this device, and their patterns of use often change over the months following initiation.

  13. Social relationships among adolescents as described in an electronic diary: a mixed methods study

    PubMed Central

    Anttila, Katriina I; Anttila, Minna J; Kurki, Marjo H; Välimäki, Maritta A

    2017-01-01

    Social relationships among adolescents with mental disorders are demanding. Adolescents with depressive symptoms may have few relationships and have difficulties sharing their problems. Internet may offer reliable and easy to use tool to collect real-time information from adolescents. The aim of this study is to explore how adolescents describe their social relationships with an electronic diary. Mixed methods were used to obtain a broad picture of adolescents’ social relationships with the data gathered from network maps and reflective texts written in an electronic diary. Adolescents who visited an outpatient clinic and used an intervention (N=70) designed for adolescents with signs of depression were invited to use the electronic diary; 29 did so. The quantitative data gathered in the electronic diary were summarized with descriptive statistics, and the qualitative data were categorized using a thematic analysis with an inductive approach. We found that social relationships among adolescents with signs of depression can vary greatly in regards to the number of existing relationships (from lacking to 21) and the quality of the relationships (from trustful to difficult). However, the relationships may change, and the adolescents are also willing to build up their social relationships. Professionals need to be aware of the diversity of adolescents’ social relationships and their need for personalized support. PMID:28280307

  14. Detection of local chemical states of lithium and their spatial mapping by scanning transmission electron microscopy, electron energy-loss spectroscopy and hyperspectral image analysis.

    PubMed

    Muto, Shunsuke; Tatsumi, Kazuyoshi

    2017-02-08

    Advancements in the field of renewable energy resources have led to a growing demand for the analysis of light elements at the nanometer scale. Detection of lithium is one of the key issues to be resolved for providing guiding principles for the synthesis of cathode active materials, and degradation analysis after repeated use of those materials. We have reviewed the different techniques currently used for the characterization of light elements such as high-resolution transmission electron microscopy, scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS). In the present study, we have introduced a methodology to detect lithium in solid materials, particularly for cathode active materials used in lithium-ion battery. The chemical states of lithium were isolated and analyzed from the overlapping multiple spectral profiles, using a suite of STEM, EELS and hyperspectral image analysis. The method was successfully applied in the chemical state analyses of hetero-phases near the surface and grain boundary regions of the active material particles formed by chemical reactions between the electrolyte and the active materials. © The Author 2016. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Controlling the thermoelectric effect by mechanical manipulation of the electron's quantum phase in atomic junctions.

    PubMed

    Aiba, Akira; Demir, Firuz; Kaneko, Satoshi; Fujii, Shintaro; Nishino, Tomoaki; Tsukagoshi, Kazuhito; Saffarzadeh, Alireza; Kirczenow, George; Kiguchi, Manabu

    2017-08-11

    The thermoelectric voltage developed across an atomic metal junction (i.e., a nanostructure in which one or a few atoms connect two metal electrodes) in response to a temperature difference between the electrodes, results from the quantum interference of electrons that pass through the junction multiple times after being scattered by the surrounding defects. Here we report successfully tuning this quantum interference and thus controlling the magnitude and sign of the thermoelectric voltage by applying a mechanical force that deforms the junction. The observed switching of the thermoelectric voltage is reversible and can be cycled many times. Our ab initio and semi-empirical calculations elucidate the detailed mechanism by which the quantum interference is tuned. We show that the applied strain alters the quantum phases of electrons passing through the narrowest part of the junction and hence modifies the electronic quantum interference in the device. Tuning the quantum interference causes the energies of electronic transport resonances to shift, which affects the thermoelectric voltage. These experimental and theoretical studies reveal that Au atomic junctions can be made to exhibit both positive and negative thermoelectric voltages on demand, and demonstrate the importance and tunability of the quantum interference effect in the atomic-scale metal nanostructures.

  16. Contributed review: Review of integrated correlative light and electron microscopy.

    PubMed

    Timmermans, F J; Otto, C

    2015-01-01

    New developments in the field of microscopy enable to acquire increasing amounts of information from large sample areas and at an increased resolution. Depending on the nature of the technique, the information may reveal morphological, structural, chemical, and still other sample characteristics. In research fields, such as cell biology and materials science, there is an increasing demand to correlate these individual levels of information and in this way to obtain a better understanding of sample preparation and specific sample properties. To address this need, integrated systems were developed that combine nanometer resolution electron microscopes with optical microscopes, which produce chemically or label specific information through spectroscopy. The complementary information from electron microscopy and light microscopy presents an opportunity to investigate a broad range of sample properties in a correlated fashion. An important part of correlating the differences in information lies in bridging the different resolution and image contrast features. The trend to analyse samples using multiple correlated microscopes has resulted in a new research field. Current research is focused, for instance, on (a) the investigation of samples with nanometer scale distribution of inorganic and organic materials, (b) live cell analysis combined with electron microscopy, and (c) in situ spectroscopic and electron microscopy analysis of catalytic materials, but more areas will benefit from integrated correlative microscopy.

  17. Psychophysical workload in the operating room: primary surgeon versus assistant.

    PubMed

    Rieger, Annika; Fenger, Sebastian; Neubert, Sebastian; Weippert, Matthias; Kreuzfeld, Steffi; Stoll, Regina

    2015-07-01

    Working in the operating room is characterized by high demands and overall workload of the surgical team. Surgeons often report that they feel more stressed when operating as a primary surgeon than in the function as an assistant which has been confirmed in recent studies. In this study, intra-individual workload was assessed in both intraoperative functions using a multidimensional approach that combined objective and subjective measures in a realistic work setting. Surgeons' intraoperative psychophysiologic workload was assessed through a mobile health system. 25 surgeons agreed to take part in the 24-hour monitoring by giving their written informed consent. The mobile health system contained a sensor electronic module integrated in a chest belt and measuring physiological parameters such as heart rate (HR), breathing rate (BR), and skin temperature. Subjective workload was assessed pre- and postoperatively using an electronic version of the NASA-TLX on a smartphone. The smartphone served as a communication unit and transferred objective and subjective measures to a communication server where data were stored and analyzed. Working as a primary surgeon did not result in higher workload. Neither NASA-TLX ratings nor physiological workload indicators were related to intraoperative function. In contrast, length of surgeries had a significant impact on intraoperative physical demands (p < 0.05; η(2) = 0.283), temporal demands (p < 0.05; η(2) = 0.260), effort (p < 0.05; η(2) = 0.287), and NASA-TLX sum score (p < 0.01; η(2) = 0.287). Intra-individual workload differences do not relate to intraoperative role of surgeons when length of surgery is considered as covariate. An intelligent operating management that considers the length of surgeries by implementing short breaks could contribute to the optimization of intraoperative workload and the preservation of surgeons' health, respectively. The value of mobile health systems for continuous psychophysiologic workload assessment was shown.

  18. New Class of Hybrid Materials for Detection, Capture, and "On-Demand" Release of Carbon Monoxide.

    PubMed

    Pitto-Barry, Anaïs; Lupan, Alexandru; Ellingford, Christopher; Attia, Amr A A; Barry, Nicolas P E

    2018-04-25

    Carbon monoxide (CO) is both a substance hazardous to health and a side product of a number of industrial processes, such as methanol steam reforming and large-scale oxidation reactions. The separation of CO from nitrogen (N 2 ) in industrial processes is considered to be difficult because of the similarities of their electronic structures, sizes, and physicochemical properties (e.g., boiling points). Carbon monoxide is also a major poison in fuel cells because of its adsorption onto the active sites of the catalysts. It is therefore of the utmost economic importance to discover new materials that enable effective CO capture and release under mild conditions. However, methods to specifically absorb and easily release CO in the presence of contaminants, such as water, nitrogen, carbon dioxide, and oxygen, at ambient temperature are not available. Here, we report the simple and versatile fabrication of a new class of hybrid materials that allows capture and release of carbon monoxide under mild conditions. We found that carborane-containing metal complexes encapsulated in networks made of poly(dimethylsiloxane) react with CO, even when immersed in water, leading to dramatic color and infrared signature changes. Furthermore, we found that the CO can be easily released from the materials by simply dipping the networks into an organic solvent for less than 1 min, at ambient temperature and pressure, which not only offers a straightforward recycling method, but also a new method for the "on-demand" release of carbon monoxide. We illustrated the utilization of the on-demand release of CO from the networks by carrying out a carbonylation reaction on an electron-deficient metal complex that led to the formation of the CO-adduct, with concomitant recycling of the gel. We anticipate that our sponge-like materials and scalable methodology will open up new avenues for the storage, transport, and controlled release of CO, the silent killer and a major industrial poison.

  19. Simple Motor Control Concept Results High Efficiency at High Velocities

    NASA Astrophysics Data System (ADS)

    Starin, Scott; Engel, Chris

    2013-09-01

    The need for high velocity motors in space applications for reaction wheels and detectors has stressed the limits of Brushless Permanent Magnet Motors (BPMM). Due to inherent hysteresis core losses, conventional BPMMs try to balance the need for torque verses hysteresis losses. Cong-less motors have significantly less hysteresis losses but suffer from lower efficiencies. Additionally, the inherent low inductance in cog-less motors result in high ripple currents or high switching frequencies, which lowers overall efficiency and increases performance demands on the control electronics.However, using a somewhat forgotten but fully qualified technology of Isotropic Magnet Motors (IMM), extremely high velocities may be achieved at low power input using conventional drive electronics. This paper will discuss the trade study efforts and empirical test data on a 34,000 RPM IMM.

  20. An Open-Source Storage Solution for Cryo-Electron Microscopy Samples.

    PubMed

    Ultee, Eveline; Schenkel, Fred; Yang, Wen; Brenzinger, Susanne; Depelteau, Jamie S; Briegel, Ariane

    2018-02-01

    Cryo-electron microscopy (cryo-EM) enables the study of biological structures in situ in great detail and to solve protein structures at Ångstrom level resolution. Due to recent advances in instrumentation and data processing, the field of cryo-EM is a rapidly growing. Access to facilities and national centers that house the state-of-the-art microscopes is limited due to the ever-rising demand, resulting in long wait times between sample preparation and data acquisition. To improve sample storage, we have developed a cryo-storage system with an efficient, high storage capacity that enables sample storage in a highly organized manner. This system is simple to use, cost-effective and easily adaptable for any type of grid storage box and dewar and any size cryo-EM laboratory.

  1. Factorization of standard model cross sections at ultrahigh energy

    NASA Astrophysics Data System (ADS)

    Chien, Yang-Ting; Li, Hsiang-nan

    2018-03-01

    The factorization theorem for organizing multiple electroweak boson emissions at future colliders with energy far above the electroweak scale is formulated. Taking the inclusive muon-pair production in electron-positron collisions as an example, we argue that the summation over isospins is demanded for constructing the universal distributions of leptons and gauge bosons in an electron. These parton distributions are shown to have the same infrared structure in the phases of broken and unbroken electroweak symmetry, an observation consistent with the Goldstone equivalence theorem. The electroweak factorization of processes involving protons is sketched, with an emphasis on the subtlety of the scalar distributions. This formalism, in which electroweak shower effects are handled from the viewpoint of factorization theorem for the first time, is an adequate framework for collider physics at ultra high energy.

  2. The third-generation turbocharged engine for the Audi 5000 CS and 5000 CS Quattro

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stock, D.

    In September 1985 the new Audi 5000 CS Quattro was introduced to the American market. This luxurious high performance touring sedan has been equipped with a more advanced turbocharged engine with intercooler and electronic engine management giving improved performance, excellent torque, faster response and better fuel economy. The basic engine is the tried-and-tested Audi 5-cylinder unit. The turbocharged engine's ancillary systems, the electronic ignition control and fuel injection have all been newly developed, carefully optimized and well matched in the special demands of a turbocharged engine. The ignition system controls the engine and fuel injection and delivers analog and digitalmore » signals to the car's instrument panel display. The system also has an integrated self-diagnostic function.« less

  3. Lumped element filters for electronic warfare systems

    NASA Astrophysics Data System (ADS)

    Morgan, D.; Ragland, R.

    1986-02-01

    Increasing demands which future generations of electronic warfare (EW) systems are to satisfy include a reduction in the size of the equipment. The present paper is concerned with lumped element filters which can make a significant contribution to the downsizing of advanced EW systems. Lumped element filter design makes it possible to obtain very small package sizes by utilizing classical low frequency inductive and capacitive components which are small compared to the size of a wavelength. Cost-effective, temperature-stable devices can be obtained on the basis of new design techniques. Attention is given to aspects of design flexibility, an interdigital filter equivalent circuit diagram, conditions for which the use of lumped element filters can be recommended, construction techniques, a design example, and questions regarding the application of lumped element filters to EW processing systems.

  4. Picoliter Drop-On-Demand Dispensing for Multiplex Liquid Cell Transmission Electron Microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patterson, Joseph P.; Parent, Lucas R.; Cantlon, Joshua

    2016-05-03

    Abstract Liquid cell transmission electron microscopy (LCTEM) provides a unique insight into the dynamics of nanomaterials in solution. Controlling the addition of multiple solutions to the liquid cell remains a key hurdle in our ability to increase throughput and to study processes dependent on solution mixing including chemical reactions. Here, we report that a piezo dispensing technique allows for mixing of multiple solutions directly within the viewing area. This technique permits deposition of 50 pL droplets of various aqueous solutions onto the liquid cell window, before assembly of the cell in a fully controlled manner. This proof-of-concept study highlights themore » great potential of picoliter dispensing in combination with LCTEM for observing nanoparticle mixing in the solution phase and the creation of chemical gradients.« less

  5. Particle-in-a-box model of one-dimensional excitons in conjugated polymers

    NASA Astrophysics Data System (ADS)

    Pedersen, Thomas G.; Johansen, Per M.; Pedersen, Henrik C.

    2000-04-01

    A simple two-particle model of excitons in conjugated polymers is proposed as an alternative to usual highly computationally demanding quantum chemical methods. In the two-particle model, the exciton is described as an electron-hole pair interacting via Coulomb forces and confined to the polymer backbone by rigid walls. Furthermore, by integrating out the transverse part, the two-particle equation is reduced to one-dimensional form. It is demonstrated how essentially exact solutions are obtained in the cases of short and long conjugation length, respectively. From a linear combination of these cases an approximate solution for the general case is obtained. As an application of the model the influence of a static electric field on the electron-hole overlap integral and exciton energy is considered.

  6. Cooper pair splitter realized in a two-quantum-dot Y-junction.

    PubMed

    Hofstetter, L; Csonka, S; Nygård, J; Schönenberger, C

    2009-10-15

    Non-locality is a fundamental property of quantum mechanics that manifests itself as correlations between spatially separated parts of a quantum system. A fundamental route for the exploration of such phenomena is the generation of Einstein-Podolsky-Rosen (EPR) pairs of quantum-entangled objects for the test of so-called Bell inequalities. Whereas such experimental tests of non-locality have been successfully conducted with pairwise entangled photons, it has not yet been possible to realize an electronic analogue of it in the solid state, where spin-1/2 mobile electrons are the natural quantum objects. The difficulty stems from the fact that electrons are immersed in a macroscopic ground state-the Fermi sea-which prevents the straightforward generation and splitting of entangled pairs of electrons on demand. A superconductor, however, could act as a source of EPR pairs of electrons, because its ground-state is composed of Cooper pairs in a spin-singlet state. These Cooper pairs can be extracted from a superconductor by tunnelling, but, to obtain an efficient EPR source of entangled electrons, the splitting of the Cooper pairs into separate electrons has to be enforced. This can be achieved by having the electrons 'repel' each other by Coulomb interaction. Controlled Cooper pair splitting can thereby be realized by coupling of the superconductor to two normal metal drain contacts by means of individually tunable quantum dots. Here we demonstrate the first experimental realization of such a tunable Cooper pair splitter, which shows a surprisingly high efficiency. Our findings open a route towards a first test of the EPR paradox and Bell inequalities in the solid state.

  7. Application of evolutionary computation in ECAD problems

    NASA Astrophysics Data System (ADS)

    Lee, Dae-Hyun; Hwang, Seung H.

    1998-10-01

    Design of modern electronic system is a complicated task which demands the use of computer- aided design (CAD) tools. Since a lot of problems in ECAD are combinatorial optimization problems, evolutionary computations such as genetic algorithms and evolutionary programming have been widely employed to solve those problems. We have applied evolutionary computation techniques to solve ECAD problems such as technology mapping, microcode-bit optimization, data path ordering and peak power estimation, where their benefits are well observed. This paper presents experiences and discusses issues in those applications.

  8. Determination of glucose concentrations using photonic crystal LEDs

    NASA Astrophysics Data System (ADS)

    Liao, Yu-Yang; Chen, Yung-Tsan; Chang, Cheng-Yu; Lan, Wen-Yi; Huang, Jian-Jang

    2016-09-01

    As internet of things (IOT) has become a popular topic in current consumer electronics, there is a demand for cost-effective sensors to monitor bio-signals. Traditional optical sensors employ low-dimensional gratings and high-resolution spectrometers to detect the refractive index changes of the solutions. In this work, we develop an alternative approach to correlate the concentration of molecules to the band diagrams of the photonic crystals. A relatively low-resolution spectrum analyzer can be employed, yet achieves higher sensitivity than traditional approaches.

  9. Content Metadata Standards for Marine Science: A Case Study

    USGS Publications Warehouse

    Riall, Rebecca L.; Marincioni, Fausto; Lightsom, Frances L.

    2004-01-01

    The U.S. Geological Survey developed a content metadata standard to meet the demands of organizing electronic resources in the marine sciences for a broad, heterogeneous audience. These metadata standards are used by the Marine Realms Information Bank project, a Web-based public distributed library of marine science from academic institutions and government agencies. The development and deployment of this metadata standard serve as a model, complete with lessons about mistakes, for the creation of similarly specialized metadata standards for digital libraries.

  10. Formal Methods for Life-Critical Software

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.; Johnson, Sally C.

    1993-01-01

    The use of computer software in life-critical applications, such as for civil air transports, demands the use of rigorous formal mathematical verification procedures. This paper demonstrates how to apply formal methods to the development and verification of software by leading the reader step-by-step through requirements analysis, design, implementation, and verification of an electronic phone book application. The current maturity and limitations of formal methods tools and techniques are then discussed, and a number of examples of the successful use of formal methods by industry are cited.

  11. The Physics and Chemistry of carbides, Nitrides and Borides. Volume 185

    DTIC Science & Technology

    1990-01-01

    and C-B-C chains [15,17]. Clearly, the use of boron-rich solids as electronic materials will place new demands on the quality of materials. In this...first heated in a pyrolytic boron nitride (PBN) crucible ( Union Carbide Corp.) under high vacuum (< 50 mTorr) to 1900°C. This removed surface...contamination of the sample. The powders were loaded into a graphite die with a high-purity BN die liner ( Union Carbide Grade HBC) with inner diameter of 3/8

  12. The AMTEX Partnership{trademark}. First quarter report, Fiscal year 1996

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1995-12-01

    The AMTEX Partnership is a collaborative research and development program among the US Integrated Textile Industry, DOE, the National Laboratories, other federal agencies and laboratories, and universities. The goal of AMTEX is to strengthen the competitiveness of this vital industry, thereby preserving and creating US jobs. Topics in this quarters report include: computer-aided fabric evaluation, cotton biotechnology, demand activated manufacturing architecture, electronic embedded fingerprints, on-line process control in flexible fiber manufacturing, rapid cutting, sensors for agile manufacturing, and textile resource conservation.

  13. Extending Interactive Electronic Technical Manuals (IETMs) with Real and Virtual Animated Content for Maintenance Task Training

    DTIC Science & Technology

    2008-12-01

    systems in a compact 2D form. This stylistic decision can give trainees a confusing or incorrect assessment of the actual layout of the corresponding...birth. Replacing these instinctual motions with mappings to a keyboard and a mouse imposes a great cognitive burden on a user; even skilled users often...can cause a situation known as ― cognitive overload,‖ in which a student, overwhelmed by the learning demands being simultaneously placed on him

  14. Diagnostic Molecular Microbiology: A 2018 Snapshot.

    PubMed

    Fairfax, Marilynn Ransom; Bluth, Martin H; Salimnia, Hossein

    2018-06-01

    Molecular biological techniques have evolved expeditiously and in turn have been applied to the detection of infectious disease. Maturation of these technologies and their coupling with related technological advancement in fluorescence, electronics, digitization, nanodynamics, and sensors among others have afforded clinical medicine additional tools toward expedient identification of infectious organisms at concentrations and sensitivities previously unattainable. These advancements have been adapted in select settings toward addressing clinical demands for more timely and effective patient management. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. New and unconventional approaches for advancing resolution in biological transmission electron microscopy by improving macromolecular specimen preparation and preservation.

    PubMed

    Massover, William H

    2011-02-01

    Resolution in transmission electron microscopy (TEM) now is limited by the properties of specimens, rather than by those of instrumentation. The long-standing difficulties in obtaining truly high-resolution structure from biological macromolecules with TEM demand the development, testing, and application of new ideas and unconventional approaches. This review concisely describes some new concepts and innovative methodologies for TEM that deal with unsolved problems in the preparation and preservation of macromolecular specimens. The selected topics include use of better support films, a more protective multi-component matrix surrounding specimens for cryo-TEM and negative staining, and, several quite different changes in microscopy and micrography that should decrease the effects of electron radiation damage; all these practical approaches are non-traditional, but have promise to advance resolution for specimens of biological macromolecules beyond its present level of 3-10 Å (0.3-1.0 nm). The result of achieving truly high resolution will be a fulfillment of the still unrealized potential of transmission electron microscopy for directly revealing the structure of biological macromolecules down to the atomic level. Published by Elsevier Ltd.

  16. Gas Electron Multipler (GEM) detectors for parity-violating electron scattering experiments at Jefferson Lab

    NASA Astrophysics Data System (ADS)

    Matter, John; Gnanvo, Kondo; Liyanage, Nilanga; Solid Collaboration; Moller Collaboration

    2017-09-01

    The JLab Parity Violation In Deep Inelastic Scattering (PVDIS) experiment will use the upgraded 12 GeV beam and proposed Solenoidal Large Intensity Device (SoLID) to measure the parity-violating electroweak asymmetry in DIS of polarized electrons with high precision in order to search for physics beyond the Standard Model. Unlike many prior Parity-Violating Electron Scattering (PVES) experiments, PVDIS is a single-particle tracking experiment. Furthermore the experiment's high luminosity combined with the SoLID spectrometer's open configuration creates high-background conditions. As such, the PVDIS experiment has the most demanding tracking detector needs of any PVES experiment to date, requiring precision detectors capable of operating at high-rate conditions in PVDIS's full production luminosity. Developments in large-area GEM detector R&D and SoLID simulations have demonstrated that GEMs provide a cost-effective solution for PVDIS's tracking needs. The integrating-detector-based JLab Measurement Of Lepton Lepton Electroweak Reaction (MOLLER) experiment requires high-precision tracking for acceptance calibration. Large-area GEMs will be used as tracking detectors for MOLLER as well. The conceptual designs of GEM detectors for the PVDIS and MOLLER experiments will be presented.

  17. Dealing with electronic waste: modeling the costs and environmental benefits of computer monitor disposal.

    PubMed

    Macauley, Molly; Palmer, Karen; Shih, Jhih-Shyang

    2003-05-01

    The importance of information technology to the world economy has brought about a surge in demand for electronic equipment. With rapid technological change, a growing fraction of the increasing stock of many types of electronics becomes obsolete each year. We model the costs and benefits of policies to manage 'e-waste' by focusing on a large component of the electronic waste stream-computer monitors-and the environmental concerns associated with disposal of the lead embodied in cathode ray tubes (CRTs) used in most monitors. We find that the benefits of avoiding health effects associated with CRT disposal appear far outweighed by the costs for a wide range of policies. For the stock of monitors disposed of in the United States in 1998, we find that policies restricting or banning some popular disposal options would increase disposal costs from about US dollar 1 per monitor to between US dollars 3 and US dollars 20 per monitor. Policies to promote a modest amount of recycling of monitor parts, including lead, can be less expensive. In all cases, however, the costs of the policies exceed the value of the avoided health effects of CRT disposal.

  18. An inverted cylindrical sputter magnetron as metal vapor supply for electron cyclotron resonance ion sources

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weichsel, T., E-mail: tim.weichsel@fep.fraunhofer.de; Hartung, U.; Kopte, T.

    2014-05-15

    An inverted cylindrical sputter magnetron device has been developed. The magnetron is acting as a metal vapor supply for an electron cyclotron resonance (ECR) ion source. FEM simulation of magnetic flux density was used to ensure that there is no critical interaction between both magnetic fields of magnetron and ECR ion source. Spatially resolved double Langmuir probe and optical emission spectroscopy measurements show an increase in electron density by one order of magnitude from 1 × 10{sup 10} cm{sup −3} to 1 × 10{sup 11} cm{sup −3}, when the magnetron plasma is exposed to the magnetic mirror field of themore » ECR ion source. Electron density enhancement is also indicated by magnetron plasma emission photography with a CCD camera. Furthermore, photographs visualize the formation of a localized loss-cone - area, when the magnetron is operated at magnetic mirror field conditions. The inverted cylindrical magnetron supplies a metal atom load rate of R > 1 × 10{sup 18} atoms/s for aluminum, which meets the demand for the production of a milliampere Al{sup +} ion beam.« less

  19. How to sustainably feed a microbe: Strategies for biological production of carbon-based commodities with renewable electricity

    DOE PAGES

    Butler, Caitlyn S.; Lovley, Derek R.

    2016-11-28

    As interest and application of renewable energy grows, strategies are needed to align the asynchronous supply and demand. Microbial metabolisms are a potentially sustainable mechanism for transforming renewable electrical energy into biocommodities that are easily stored and transported. Acetogens and methanogens can reduce carbon dioxide to organic products including methane, acetic acid, and ethanol. The library of biocommodities is expanded when engineered metabolisms of acetogens are included. Typically, electrochemical systems are employed to integrate renewable energy sources with biological systems for production of carbon-based commodities. Within these systems, there are three prevailing mechanisms for delivering electrons to microorganisms for themore » conversion of carbon dioxide to reduce organic compounds: (1) electrons can be delivered to microorganisms via H 2 produced separately in a electrolyzer, (2) H 2 produced at a cathode can convey electrons to microorganisms supported on the cathode surface, and (3) a cathode can directly feed electrons to microorganisms. Each of these strategies has advantages and disadvantages that must be considered in designing full-scale processes. Furthermore, this review considers the evolving understanding of each of these approaches and the state of design for advancing these strategies toward viability.« less

  20. Intranet and village community: optimization of public service based on electronic government at the local level

    NASA Astrophysics Data System (ADS)

    Pradana, G. W.; Fanida, E. H.; Niswah, F.

    2018-01-01

    The demand for good governance is directed towards the realization of efficiency, effectiveness, and clean government. The move is demonstrated through national and regional levels to develop and implement electronic government concepts. Through the development of electronic government is done structuring management systems and work processes in the government environment by optimizing the utilization of information technology. One of the real forms of electronic government (e-Gov) implementation at the local level is the Intranet Sub-District program in Sukodono Sub-District, Sidoarjo. Intranet Sub-District is an innovation whose purpose is to realize the availability of information on the utilization of management, distribution, and storage of official scripts, and also the optimal delivery of information and communication in the implementation of guidance and supervision of local administration. The type of this paper is descriptive with a qualitative approach and focus on the implementation of the Intranet District Program in Sukodono District, Sidoarjo. The findings of the study are the limited number of human resources who have mastered ICT, the uneven network, the adequacy of institutional needs and the existence of budget support from the authorized institution and the information system has not accommodated all the service needs.

  1. Ultrasoft pseudopotentials and Hubbard U values for rare-earth elements (Re=La-Lu) guided by HSE06 calculations

    NASA Astrophysics Data System (ADS)

    Topsakal, Mehmet; Umemoto, Koichiro; Wentzcovitch, Renata

    2014-03-01

    The lanthanide series of the periodic table comprises fifteen members ranging from La to Lu - the rare-earth (Re) elements. They exhibit unique (and mostly unexplored) chemical properties depending on the fillings of 4f-orbitals. Due to strong electronic correlation, 4f valence electrons are incorrectly described by standard DFT functionals. In order to cope with these inefficiencies, the DFT+U method is often employed where Hubbard-type U is introduced into the standard DFT. Another approach is to use hybrid functionals. Both improve the treatment of strongly correlated electrons. However, DFT+U suffers from ambiguity of U while hybrid functionals suffer from extremely demanding computational costs. Here we provide Vanderbilt type ultrasoft pseudopotentials for Re elements with suggested U values allowing efficient plane-wave calculations. Hubbard U values are determined according to HSE06 calculations on Re-nitrides (ReN). Generated pseudopotentials were further tested on some Re-cobaltite (Re-CoO3) perovskites. Alternative pseudopotentials with f-electrons kept frozen in the core of pseudopotential are also provided and possible outcomes are addressed. We believe that these new pseudopotentials with suggested U values will allow further studies on rare-earth materials.

  2. Electron beam detection of a Nanotube Scanning Force Microscope.

    PubMed

    Siria, Alessandro; Niguès, Antoine

    2017-09-14

    Atomic Force Microscopy (AFM) allows to probe matter at atomic scale by measuring the perturbation of a nanomechanical oscillator induced by near-field interaction forces. The quest to improve sensitivity and resolution of AFM forced the introduction of a new class of resonators with dimensions at the nanometer scale. In this context, nanotubes are the ultimate mechanical oscillators because of their one dimensional nature, small mass and almost perfect crystallinity. Coupled to the possibility of functionalisation, these properties make them the perfect candidates as ultra sensitive, on-demand force sensors. However their dimensions make the measurement of the mechanical properties a challenging task in particular when working in cavity free geometry at ambient temperature. By using a focused electron beam, we show that the mechanical response of nanotubes can be quantitatively measured while approaching to a surface sample. By coupling electron beam detection of individual nanotubes with a custom AFM we image the surface topography of a sample by continuously measuring the mechanical properties of the nanoresonators. The combination of very small size and mass together with the high resolution of the electron beam detection method offers unprecedented opportunities for the development of a new class of nanotube-based scanning force microscopy.

  3. Inelastic transport theory from first principles: Methodology and application to nanoscale devices

    NASA Astrophysics Data System (ADS)

    Frederiksen, Thomas; Paulsson, Magnus; Brandbyge, Mads; Jauho, Antti-Pekka

    2007-05-01

    We describe a first-principles method for calculating electronic structure, vibrational modes and frequencies, electron-phonon couplings, and inelastic electron transport properties of an atomic-scale device bridging two metallic contacts under nonequilibrium conditions. The method extends the density-functional codes SIESTA and TRANSIESTA that use atomic basis sets. The inelastic conductance characteristics are calculated using the nonequilibrium Green’s function formalism, and the electron-phonon interaction is addressed with perturbation theory up to the level of the self-consistent Born approximation. While these calculations often are computationally demanding, we show how they can be approximated by a simple and efficient lowest order expansion. Our method also addresses effects of energy dissipation and local heating of the junction via detailed calculations of the power flow. We demonstrate the developed procedures by considering inelastic transport through atomic gold wires of various lengths, thereby extending the results presented in Frederiksen [Phys. Rev. Lett. 93, 256601 (2004)]. To illustrate that the method applies more generally to molecular devices, we also calculate the inelastic current through different hydrocarbon molecules between gold electrodes. Both for the wires and the molecules our theory is in quantitative agreement with experiments, and characterizes the system-specific mode selectivity and local heating.

  4. Simulating Lattice Image of Suspended Graphene Taken by Helium Ion Microscopy

    NASA Astrophysics Data System (ADS)

    Miyamoto, Yoshiyuki; Zhang, Hong; Rubio, Angel

    2013-03-01

    Atomic scale image in nano-scale helps us to characterize property of graphene, and performance of high-resolution transmission electron microscopy (HRTEM) is significant, so far. While a tool without pre-treatment of samples is demanded in practice. Helium ion microscopy (HIM), firstly reported by Word et. al. in 2006, was applied for monitoring graphene in device structure (Lumme, et. al., 2009). Motivated by recent HIM explorations, we examined the possibility of taking lattice image of suspended graphene by HIM. The intensity of secondary emitted electron is recorded as a profile of scanned He+-beam in HIM measurement. We mimicked this situation by performing electron-ion dynamics based on the first-principles simulation within the time-dependent density functional theory. He+ ion collision on single graphene sheet at several impact points were simulated and we found that the amount of secondary emitted electron from graphene reflected the valence charge distribution of the graphene sheet. Therefore HIM using atomically thin He-beam should be able to provide the lattice image, and we propose that an experiment generating ultra-thin He+ ion beam (Rezeq et. al., 2006) should be combined with HIM technique. All calculations were performed by using the Earth Simulator.

  5. First principles investigations of vinazene molecule and molecular crystal: a prospective candidate for organic photovoltaic applications.

    PubMed

    Mohamad, Mazmira; Ahmed, Rashid; Shaari, Amirudin; Goumri-Said, Souraya

    2015-02-01

    Escalating demand for sustainable energy resources, because of the rapid exhaustion of conventional energy resources as well as to maintain the environmental level of carbon dioxide (CO2) to avoid its adverse effect on the climate, has led to the exploitation of photovoltaic technology manifold more than ever. In this regard organic materials have attracted great attention on account of demonstrating their potential to harvest solar energy at an affordable rate for photovoltaic technology. 2-vinyl-4,5-dicyanoimidazole (vinazene) is considered as a suitable material over the fullerenes for photovoltaic applications because of its particular chemical and physical nature. In the present study, DFT approaches are employed to provide an exposition of optoelectronic properties of vinazene molecule and molecular crystal. To gain insight into its properties, different forms of exchange correlation energy functional/potential such as LDA, GGA, BLYP, and BL3YP are used. Calculated electronic structure of vinazene molecule has been displayed via HOMO-LUMO isosurfaces, whereas electronic structure of the vinazene molecular crystal, via electronic band structure, is presented. The calculated electronic and optical properties were analyzed and compared as well. Our results endorse vinazene as a suitable material for organic photovoltaic applications.

  6. How to sustainably feed a microbe: Strategies for biological production of carbon-based commodities with renewable electricity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Butler, Caitlyn S.; Lovley, Derek R.

    As interest and application of renewable energy grows, strategies are needed to align the asynchronous supply and demand. Microbial metabolisms are a potentially sustainable mechanism for transforming renewable electrical energy into biocommodities that are easily stored and transported. Acetogens and methanogens can reduce carbon dioxide to organic products including methane, acetic acid, and ethanol. The library of biocommodities is expanded when engineered metabolisms of acetogens are included. Typically, electrochemical systems are employed to integrate renewable energy sources with biological systems for production of carbon-based commodities. Within these systems, there are three prevailing mechanisms for delivering electrons to microorganisms for themore » conversion of carbon dioxide to reduce organic compounds: (1) electrons can be delivered to microorganisms via H 2 produced separately in a electrolyzer, (2) H 2 produced at a cathode can convey electrons to microorganisms supported on the cathode surface, and (3) a cathode can directly feed electrons to microorganisms. Each of these strategies has advantages and disadvantages that must be considered in designing full-scale processes. Furthermore, this review considers the evolving understanding of each of these approaches and the state of design for advancing these strategies toward viability.« less

  7. How to Sustainably Feed a Microbe: Strategies for Biological Production of Carbon-Based Commodities with Renewable Electricity.

    PubMed

    Butler, Caitlyn S; Lovley, Derek R

    2016-01-01

    As interest and application of renewable energy grows, strategies are needed to align the asynchronous supply and demand. Microbial metabolisms are a potentially sustainable mechanism for transforming renewable electrical energy into biocommodities that are easily stored and transported. Acetogens and methanogens can reduce carbon dioxide to organic products including methane, acetic acid, and ethanol. The library of biocommodities is expanded when engineered metabolisms of acetogens are included. Typically, electrochemical systems are employed to integrate renewable energy sources with biological systems for production of carbon-based commodities. Within these systems, there are three prevailing mechanisms for delivering electrons to microorganisms for the conversion of carbon dioxide to reduce organic compounds: (1) electrons can be delivered to microorganisms via H 2 produced separately in a electrolyzer, (2) H 2 produced at a cathode can convey electrons to microorganisms supported on the cathode surface, and (3) a cathode can directly feed electrons to microorganisms. Each of these strategies has advantages and disadvantages that must be considered in designing full-scale processes. This review considers the evolving understanding of each of these approaches and the state of design for advancing these strategies toward viability.

  8. Electrode architectures for efficient electronic and ionic transport pathways in high power lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Faulkner, Ankita Shah

    As the demand for clean energy sources increases, large investments have supported R&D programs aimed at developing high power lithium ion batteries for electric vehicles, military, grid storage and space applications. State of the art lithium ion technology cannot meet power demands for these applications due to high internal resistances in the cell. These resistances are mainly comprised of ionic and electronic resistance in the electrode and electrolyte. Recently, much attention has been focused on the use of nanoscale lithium ion active materials on the premise that these materials shorten the diffusion length of lithium ions and increase the surface area for electrochemical charge transfer. While, nanomaterials have allowed significant improvements in the power density of the cell, they are not a complete solution for commercial batteries. Due to their large surface area, they introduce new challenges such as a poor electrode packing densities, high electrolyte reactivity, and expensive synthesis procedures. Since greater than 70% of the cost of the electric vehicle is due to the cost of the battery, a cost-efficient battery design is most critical. To address the limitations of nanomaterials, efficient transport pathways must be engineered in the bulk electrode. As a part of nanomanufacturing research being conducted the Center for High-rate Nanomanufacturing at Northeastern University, the first aim of the proposed work is to develop electrode architectures that enhance electronic and ionic transport pathways in large and small area lithium ion electrodes. These architectures will utilize the unique electronic and mechanical properties of carbon nanotubes to create robust electrode scaffolding that improves electrochemical charge transfer. Using extensive physical and electrochemical characterization, the second aim is to investigate the effect of electrode parameters on electrochemical performance and evaluate the performance against standard commercial electrodes. These parameters include surface morphology, electrode composition, electrode density, and operating temperature. Finally, the third aim is to investigate commercial viability of the electrode architecture. This will be accomplished by developing pouch cell prototypes using a high-rate and low cost scale-up process. Through this work, we aim to realize a commercially viable high-power electrode technology.

  9. Capacity-oriented curriculum system of optoelectronics in the context of large category cultivation

    NASA Astrophysics Data System (ADS)

    Luo, Yuan; Hu, Zhangfang; Zhang, Yi

    2017-08-01

    In order to cultivate the innovative talents with the comprehensive development to meet the talents demand for development of economic society, Chongqing University of Posts and Telecommunications implements cultivation based on broadening basic education and enrolment in large category of general education. Optoelectronic information science and engineering major belongs to the electronic engineering category. The "2 +2" mode is utilized for personnel training, where students are without major in the first and second year and assigned to a major within the major categories in the end of the second year. In the context of the comprehensive cultivation, for the changes in the demand for professionals in the global competitive environment with the currently rapid development, especially the demand for the professional engineering technology personnel suitable to industry and development of local economic society, the concept of CDIO engineering ability cultivation is used for reference. Thus the curriculum system for the three-node structure optoelectronic information science and engineering major is proposed, which attaches great importance to engineering practice and innovation cultivation under the background of the comprehensive cultivation. The conformity between the curriculum system and the personnel training objectives is guaranteed effectively, and the consistency between the teaching philosophy and the teaching behavior is enhanced. Therefore, the idea of major construction is clear with specific characteristics.

  10. Optimal reduction of chemical oxygen demand and NH3-N from landfill leachate using a strongly resistant novel Bacillus salmalaya strain.

    PubMed

    Dadrasnia, Arezoo; Azirun, Mohd Sofian; Ismail, Salmah Binti

    2017-11-28

    When the unavoidable waste generation is considered as damaging to our environment, it becomes crucial to develop a sustainable technology to remediate the pollutant source towards an environmental protection and safety. The development of a bioengineering technology for highly efficient pollutant removal is this regard. Given the high ammonia nitrogen content and chemical oxygen demand of landfill leachate, Bacillus salmalaya strain 139SI, a novel resident strain microbe that can survive in high ammonia nitrogen concentrations, was investigated for the bioremoval of ammonia nitrogen from landfill leachate. The treatability of landfill leachate was evaluated under different treatment parameters, such as temperature, inoculum dosage, and pH. Results demonstrated that bioaugmentation with the novel strain can potentially improve the biodegradability of landfill leachate. B. salmalaya strain 139SI showed high potential to enhance biological treatment given its maximum NH 3 -N and COD removal efficiencies. The response surface plot pattern indicated that within 11 days and under optimum conditions (10% v/v inoculant, pH 6, and 35 °C), B. salmalaya strain139SI removed 78% of ammonia nitrogen. At the end of the study, biological and chemical oxygen demands remarkably decreased by 88% and 91.4%, respectively. Scanning electron microscopy images revealed that ammonia ions covered the cell surface of B. salmalaya strain139SI. Therefore, novel resistant Bacillus salmalaya strain139SI significantly reduces the chemical oxygen demand and NH 3 -N content of landfill leachate. Leachate treatment by B. salmalaya strain 139SI within 11 days.

  11. To what extent does sociodemographic composition of the neighbourhood explain regional differences in demand of primary out-of-hours care: a multilevel study.

    PubMed

    Jansen, Tessa; Zwaanswijk, Marieke; Hek, Karin; de Bakker, Dinny

    2015-05-06

    In the Netherlands, primary out-of-hours (OOH) care is provided by large scale General Practitioner (GP) cooperatives. GP cooperatives can be contacted by patients living in the area surrounding the GP cooperative (catchment area) at hours when the patient's own general practice is closed. The frequency of primary OOH care use substantially differs between GP cooperative catchment areas. To enable a better match between supply and demand of OOH services, understanding of the factors associated with primary OOH care use is essential. The present study evaluated the contribution of sociodemographic composition of the neighbourhood in explaining differences in primary OOH care use between GP cooperative catchment areas. Data about patients' contacts with primary OOH services (n = 1,668,047) were derived from routine electronic health records of 21 GP cooperatives participating in the NIVEL Primary Care Database in 2012. The study sample is representative for the Dutch population (for age and gender). Data were matched with sociodemographic characteristics (e.g. gender, age, low-income status, degree of urbanisation) on postcode level. Multilevel linear regression models included postcode level (first level), nested within GP cooperative catchment areas (second level). We investigated whether contacts in primary OOH care were associated with neighbourhood sociodemographic characteristics. The demand of primary OOH care was significantly higher in neighbourhoods with more women, low-income households, non-Western immigrants, neighbourhoods with a higher degree of urbanisation, and low neighbourhood socioeconomic status. Conversely, lower demand was associated with neighbourhoods with more 5 to 24 year old inhabitants. Sociodemographic neighbourhood characteristics explained a large part of the variation between GP cooperatives (R-squared ranging from 8% to 52%). Nevertheless, the multilevel models also showed that a considerable amount of variation in demand between GP cooperatives remained unexplained by sociodemographic characteristics, particularly regarding high-urgency contacts. Although part of the variation between GP cooperatives could not be attributed to neighbourhood characteristics, the sociodemographic composition of the neighbourhood is a fair predictor of the demand of primary OOH care. Accordingly, this study provides a useful starting point for an improved planning of the supply of primary OOH care.

  12. Transparent and flexible resistive switching memory devices with a very high ON/OFF ratio using gold nanoparticles embedded in a silk protein matrix

    NASA Astrophysics Data System (ADS)

    Gogurla, Narendar; Mondal, Suvra P.; Sinha, Arun K.; Katiyar, Ajit K.; Banerjee, Writam; Kundu, Subhas C.; Ray, Samit K.

    2013-08-01

    The growing demand for biomaterials for electrical and optical devices is motivated by the need to make building blocks for the next generation of printable bio-electronic devices. In this study, transparent and flexible resistive memory devices with a very high ON/OFF ratio incorporating gold nanoparticles into the Bombyx mori silk protein fibroin biopolymer are demonstrated. The novel electronic memory effect is based on filamentary switching, which leads to the occurrence of bistable states with an ON/OFF ratio larger than six orders of magnitude. The mechanism of this process is attributed to the formation of conductive filaments through silk fibroin and gold nanoparticles in the nanocomposite. The proposed hybrid bio-inorganic devices show promise for use in future flexible and transparent nanoelectronic systems.

  13. Emergent functions of quantum materials

    NASA Astrophysics Data System (ADS)

    Tokura, Yoshinori; Kawasaki, Masashi; Nagaosa, Naoto

    2017-11-01

    Materials can harbour quantum many-body systems, most typically in the form of strongly correlated electrons in solids, that lead to novel and remarkable functions thanks to emergence--collective behaviours that arise from strong interactions among the elements. These include the Mott transition, high-temperature superconductivity, topological superconductivity, colossal magnetoresistance, giant magnetoelectric effect, and topological insulators. These phenomena will probably be crucial for developing the next-generation quantum technologies that will meet the urgent technological demands for achieving a sustainable and safe society. Dissipationless electronics using topological currents and quantum spins, energy harvesting such as photovoltaics and thermoelectrics, and secure quantum computing and communication are the three major fields of applications working towards this goal. Here, we review the basic principles and the current status of the emergent phenomena and functions in materials from the viewpoint of strong correlation and topology.

  14. Recent advances in design and fabrication of on-chip micro-supercapacitors

    NASA Astrophysics Data System (ADS)

    Beidaghi, Majid; Wang, Chunlei

    2012-06-01

    Recent development in miniaturized electronic devices has increased the demand for power sources that are sufficiently compact and can potentially be integrated on a chip with other electronic components. Miniaturized electrochemical capacitors (EC) or micro-supercapacitors have great potential to complement or replace batteries and electrolytic capacitors in a variety of applications. Recently, we have developed several types of micro-supercapacitors with different structural designs and active materials. Carbon-Microelectromechanical Systems (C-MEMS) with three dimensional (3D) interdigital structures are employed both as electrode material for electric double layer capacitor (EDLC) or as three dimensional (3D) current collectors of pseudo-capacitive materials. More recently, we have also developed microsupercapacitor based on hybrid graphene and carbon nanotube interdigital structures. In this paper, the recent advances in design and fabrication of on-chip micro-supercapacitors are reviewed.

  15. Copper vertical micro dendrite fin arrays and their superior boiling heat transfer capability

    NASA Astrophysics Data System (ADS)

    Wang, Ya-Qiao; Lyu, Shu-Shen; Luo, Jia-Li; Luo, Zhi-Yong; Fu, Yuan-Xiang; Heng, Yi; Zhang, Jian-Hui; Mo, Dong-Chuan

    2017-11-01

    Micro pin fin arrays have been widely used in electronic cooling, micro reactors, catalyst support, and wettability modification and so on, and a facile way to produce better micro pin fin arrays is demanded. Herein, a simple electrochemical method has been developed to fabricate copper vertical micro dendrite fin arrays (Cu-VMDFA) with controllable shapes, number density and height. High copper sulphate concentration is one key point to make the dendrite stand vertically. Besides, the applied current should rise at an appropriate rate to ensure the copper dendrite can grow vertically on its own. The Cu-VMDFA can significantly enhance the heat transfer coefficient by approximately twice compared to the plain copper surface. The Cu-VMDFA may be widely used in boiling heat transfer areas such as nuclear power plants, electronic cooling, heat exchangers, and so on.

  16. A web-based rapid prototyping and clinical conversational system that complements electronic patient record system.

    PubMed

    Kim, J H; Ferziger, R; Kawaloff, H B; Sands, D Z; Safran, C; Slack, W V

    2001-01-01

    Even the most extensive hospital information system cannot support all the complex and ever-changing demands associated with a clinical database, such as providing department or personal data forms, and rating scales. Well-designed clinical dialogue programs may facilitate direct interaction of patients with their medical records. Incorporation of extensive and loosely structured clinical data into an existing medical record system is an essential step towards a comprehensive clinical information system, and can best be achieved when the practitioner and the patient directly enter the contents. We have developed a rapid prototyping and clinical conversational system that complements the electronic medical record system, with its generic data structure and standard communication interfaces based on Web technology. We believe our approach can enhance collaboration between consumer-oriented and provider-oriented information systems.

  17. Investigating the edge state of graphene nanoribbons by a chemical approach: Synthesis and magnetic properties of zigzag-edged nanographene molecules

    NASA Astrophysics Data System (ADS)

    Konishi, Akihito; Hirao, Yasukazu; Kurata, Hiroyuki; Kubo, Takashi

    2013-12-01

    The edge state, which is a peculiar magnetic state in zigzag-edged graphene nanoribbons (GNRs) originating from an electron-electron correlation in an edge-localized π-state, has promising applications for magnetic and spintronics devices and has attracted much attention of physicists, chemists, and engineers. For deeper understanding the edge state, precise fabrication of edge structures in GNRs has been highly demanded. We focus on [a.b]periacene, which are polycyclic aromatic hydrocarbons (PAHs) that have zigzag and armchair edges on molecular periphery, as a model compound for the understanding and actually prepare and characterize them. This review summarizes our recent studies on the origin of the edge state by investigating [a.b]periacene in terms of the relationship between the molecular structure and spin-localizing character.

  18. Producing gallium arsenide crystals in space

    NASA Technical Reports Server (NTRS)

    Randolph, R. L.

    1984-01-01

    The production of high quality crystals in space is a promising near-term application of microgravity processing. Gallium arsenide is the selected material for initial commercial production because of its inherent superior electronic properties, wide range of market applications, and broad base of on-going device development effort. Plausible product prices can absorb the high cost of space transportation for the initial flights provided by the Space Transportation System. The next step for bulk crystal growth, beyond the STS, is planned to come later with the use of free flyers or a space station, where real benefits are foreseen. The use of these vehicles, together with refinement and increasing automation of space-based crystal growth factories, will bring down costs and will support growing demands for high quality GaAs and other specialty electronic and electro-optical crystals grown in space.

  19. [Progress in the application of laser ablation ICP-MS to surface microanalysis in material science].

    PubMed

    Zhang, Yong; Jia, Yun-hai; Chen, Ji-wen; Shen, Xue-jing; Liu, Ying; Zhao, Leiz; Li, Dong-ling; Hang, Peng-cheng; Zhao, Zhen; Fan, Wan-lun; Wang, Hai-zhou

    2014-08-01

    In the present paper, apparatus and theory of surface analysis is introduced, and the progress in the application of laser ablation ICP-MS to microanalysis in ferrous, nonferrous and semiconductor field is reviewed in detail. Compared with traditional surface analytical tools, such as SEM/EDS (scanning electron microscopy/energy dispersive spectrum), EPMA (electron probe microanalysis analysis), AES (auger energy spectrum), etc. the advantage is little or no sample preparation, adjustable spatial resolution according to analytical demand, multi-element analysis and high sensitivity. It is now a powerful complementary method to traditional surface analytical tool. With the development of LA-ICP-MS technology maturing, more and more analytical workers will use this powerful tool in the future, and LA-ICP-MS will be a super star in elemental analysis field just like LIBS (Laser-induced breakdown spectroscopy).

  20. Smart signal processing for an evolving electric grid

    NASA Astrophysics Data System (ADS)

    Silva, Leandro Rodrigues Manso; Duque, Calos Augusto; Ribeiro, Paulo F.

    2015-12-01

    Electric grids are interconnected complex systems consisting of generation, transmission, distribution, and active loads, recently called prosumers as they produce and consume electric energy. Additionally, these encompass a vast array of equipment such as machines, power transformers, capacitor banks, power electronic devices, motors, etc. that are continuously evolving in their demand characteristics. Given these conditions, signal processing is becoming an essential assessment tool to enable the engineer and researcher to understand, plan, design, and operate the complex and smart electronic grid of the future. This paper focuses on recent developments associated with signal processing applied to power system analysis in terms of characterization and diagnostics. The following techniques are reviewed and their characteristics and applications discussed: active power system monitoring, sparse representation of power system signal, real-time resampling, and time-frequency (i.e., wavelets) applied to power fluctuations.

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