WorldWideScience

Sample records for hybrid performance electronic

  1. Hybrid printed electronics

    NARCIS (Netherlands)

    Koetse, M.; Smits, E.; Rubingh, E.; Teunissen, P.; Kusters, R.; Abbel, R.; Brand, J. van den

    2016-01-01

    Although many electronic functionalities can be realized by printed or organic electronics, short-term marketable products often require robust, reproducible, and nondisturbing technologies. In this chapter we show how hybrid electronics, a combination of printed circuitry, thin-film electronics,

  2. Cross-Linkable and Dual Functional Hybrid Polymeric Electron Transporting Layer for High-Performance Inverted Polymer Solar Cells.

    Science.gov (United States)

    Dong, Sheng; Hu, Zhicheng; Zhang, Kai; Yin, Qingwu; Jiang, Xiaofang; Huang, Fei; Cao, Yong

    2017-06-20

    A cross-linkable dual functional polymer hybrid electron transport layer (ETL) is developed by simply adding an amino-functionalized polymer dopant (PN4N) and a light crosslinker into a commercialized n-type semiconductor (N2200) matrix. It is found that the resulting hybrid ETL not only has a good solvent resistance, facilitating multilayers device fabrication but also exhibits much improved electron transporting/extraction properties due to the doping between PN4N and N2200. As a result, by using PTB7-Th:PC71 BM blend as an active layer, the inverted device based on the hybrid ETL can yield a prominent power conversion efficiency of around 10.07%. More interestingly, photovoltaic property studies of bilayer devices suggest that the absorption of the hybrid ETL contributes to photocurrent and hence the hybrid ETL simultaneously acts as both cathode interlayer material and an electron acceptor. The resulting inverted polymer solar cells function like a novel device architectures with a combination of a bulk heterojunction device and miniature bilayer devices. This work provides new insights on function of ETLs and may be open up a new direction for the design of new ETL materials and novel device architectures to further improve device performance. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Electron-transporting small molecule/ o-xylene hybrid additives to boost the performance of simplified inverted polymer solar cells

    Science.gov (United States)

    Qin, Dashan; Cao, Huan; Zhang, Jidong

    2017-05-01

    Electron-transporting small molecule bathophenanthroline (Bphen) together with o-xylene has been used as hybrid additives to improve the performance of simplified inverted polymer solar cells employing ITO alone as cathode and photoactive layer based on polymer [[2,6'-4,8-di(5-ethylhexylthienyl)benzo[1,2-b;3,3-b] dithiophene] [3-fluoro-2[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl

  4. Photon counting performance measurements of transfer electron InGaAsP photocathode hybrid photomultiplier tubes at 1064 nm wavelength

    Science.gov (United States)

    Sun, Xiaoli; Krainak, Michael A.; Hasselbrack, William B.; La Rue, Ross A.

    2007-05-01

    We report the test results of a hybrid photomultiplier tube (HPMT) with a transfer electron (TE) InGaAsP photocathode and GaAs Schottky avalanche photodiode (APD) anode. Unlike Geiger mode InGaAsP APDs, these HPMTs (also known as intensified photodiode (IPD), vacuum APD, or hybrid photodetector) operate in linear mode without the need for quenching and gating. Their greatest advantages are wide dynamic range, high speed, large photosensitive area, and potential for photon counting and analog detection dual mode operation. The photon detection efficiency we measured was 25% at 1064 nm wavelength with a dark count rate of 60,000/s at -22 degrees Celsius. The output pulse width in response to a single photon detection is about 0.9 ns. The maximum count rate was 90 Mcts/s and was limited solely by the speed of the discriminator used in the measurement (10 ns dead time). The spectral response of these devices extended from 900 to 1300 nm. We also measured the HPMT response to 60 ps laser pulses. The average output pulse amplitude increased monotonically with the input pulse energy, which suggested that we can resolve photon number in an incident pulse. The jitter of the HPMT output was found to be about 0.5 ns standard deviation and depended on bias voltage applied to the TE photocathode. To our knowledge, these HPMTs are the most sensitive non gating photon detectors at 1064 nm wavelength, and they will have many applications in laser altimeters, atmospheric lidars, and free space laser communication systems.

  5. 3D-hybrid material design with electron/lithium-ion dual-conductivity for high-performance Li-sulfur batteries

    Science.gov (United States)

    Zhao, Yan; Tan, Rui; Yang, Jie; Wang, Kai; Gao, Rongtan; Liu, Dong; Liu, Yidong; Yang, Jinlong; Pan, Feng

    2017-02-01

    We report a novel 3D-hybrid cathode material with three-dimensional (3D) N-GO/CNT framework to load sulfur (77.6 wt %), and sulfonated polyaniline (SPANI) of coating layer. Used as a cathode material, it possesses a high capacity (1196 mAh g-1@0.3 A g-1@1.6 mg cm-2), excellent charging-discharging rate (680 mAh g-1@7.5 A g-1) and long-life performance (maintaining 71.1% capacity over 450 cycles), which is mainly attributed to the benefits of excellent electronic/Li-ionic dual-conductivity and confinement effect of the 3D-hybrid N-GO/CNT framework coated by self-doping conducting polymer SPANI. Thus, a 3D sulfur cathode modified with electronic/Li-ionic dual-conduction network can significantly enhance the electrochemical performance and stability, and this novel type of material is very promising for commercial applications that require high energy and power density, long life, and excellent abuse tolerance.

  6. NextFlex Flexible Hybrid Electronics Manufacturing

    Science.gov (United States)

    2016-10-01

    and innovators, along with a robust U.S. network of manufacturing nodes, to advance a national flexible hybrid electronics (FHE) manufacturing...methods to scale up today’s FHE laboratory experiments into smart , affordable products. FHE manufacturing en- compasses innovative electronic...The software design tools will encompass multiphysics simulation (e.g., electrical , thermal, mechanical, etc., interactions based on first principles

  7. Performance of hybrid photovoltaic collector

    OpenAIRE

    Garbisu Eugui, Josu

    2010-01-01

    The aim of the present project is the study of the performance of a combined photovoltaic-thermal plant, called also hybrid system, located in south Italy, evaluating the efficiency of the photovoltaic and thermal systems and the advantage respect to the two single plants (photovoltaic and thermal ). This research project has two objectives fundamentals of efficiency improvement energy from solar photovoltaic panels. On one hand, increase photovoltaic efficiency, at the same time an...

  8. Enhanced performance hybrid-arq

    KAUST Repository

    Fareed, Muhammad Mehboob

    2016-06-16

    Apparatuses, computer readable media, and methods are provided for enhancing hybrid automatic repeat request (ARQ) performance. In an example method, a communication device transmits a first element of a vector, where the vector is selected using the information bits to be transmitted as an index in a code book. In some embodiments, this code book is constructed using Linear Constellation Precoding (LCP). If a NACK is received, the communication device transmits a second element of the vector. The process of transmitting elements of the vector continues until an ACK is received or the maximum number of transmission attempts is reached. If an ACK is received, the communication device transmits a first element of another vector of the code book that encodes a second set of information bits. This procedure may continue until all information bits have been transmitted successfully.

  9. Triple Hybrid Energy Harvesting Interface Electronics

    Science.gov (United States)

    Uluşan, H.; Chamanian, S.; Pathirana, W. M. P. R.; Zorlu, Ö.; Muhtaroğlu, A.; Külah, H.

    2016-11-01

    This study presents a novel triple hybrid system that combines simultaneously generated power from thermoelectric (TE), vibration-based electromagnetic (EM) and piezoelectric (PZT) harvesters for a relatively high power supply capability. In the proposed solution each harvesting source utilizes a distinct power management circuit that generates a DC voltage suitable for combining the three parallel supplies. The circuits are designed and implemented in 180 nm standard CMOS technology, and are terminated with a schottky diode to avoid reverse current flow. The harvested AC signal from the EM harvester is rectified with a self-powered AC-DC doubler, which utilizes active diode structures to minimize the forward- bias voltage drop. The PZT interface electronics utilizes a negative voltage converter as the first stage, followed by synchronous power extraction and DC-to-DC conversion through internal switches, and an external inductor. The ultra-low voltage DC power harvested by the TE generator is stepped up through a charge-pump driven by an LC oscillator with fully- integrated center-tapped differential inductors. Test results indicate that hybrid energy harvesting circuit provides more than 1 V output for load resistances higher than 100 kΩ (10 μW) where the stand-alone harvesting circuits are not able to reach 1 V output. This is the first hybrid harvester circuit that simultaneously extracts energy from three independent sources, and delivers a single DC output.

  10. Genomic Prediction of Barley Hybrid Performance

    Directory of Open Access Journals (Sweden)

    Norman Philipp

    2016-07-01

    Full Text Available Hybrid breeding in barley ( L. offers great opportunities to accelerate the rate of genetic improvement and to boost yield stability. A crucial requirement consists of the efficient selection of superior hybrid combinations. We used comprehensive phenotypic and genomic data from a commercial breeding program with the goal of examining the potential to predict the hybrid performances. The phenotypic data were comprised of replicated grain yield trials for 385 two-way and 408 three-way hybrids evaluated in up to 47 environments. The parental lines were genotyped using a 3k single nucleotide polymorphism (SNP array based on an Illumina Infinium assay. We implemented ridge regression best linear unbiased prediction modeling for additive and dominance effects and evaluated the prediction ability using five-fold cross validations. The prediction ability of hybrid performances based on general combining ability (GCA effects was moderate, amounting to 0.56 and 0.48 for two- and three-way hybrids, respectively. The potential of GCA-based hybrid prediction requires that both parental components have been evaluated in a hybrid background. This is not necessary for genomic prediction for which we also observed moderate cross-validated prediction abilities of 0.51 and 0.58 for two- and three-way hybrids, respectively. This exemplifies the potential of genomic prediction in hybrid barley. Interestingly, prediction ability using the two-way hybrids as training population and the three-way hybrids as test population or vice versa was low, presumably, because of the different genetic makeup of the parental source populations. Consequently, further research is needed to optimize genomic prediction approaches combining different source populations in barley.

  11. Flexural performance of woven hybrid composites

    Science.gov (United States)

    Maslinda, A. B.; Majid, M. S. Abdul; Dan-mallam, Y.; Mazawati, M.

    2016-07-01

    This paper describes the experimental investigation of the flexural performance of natural fiber reinforced polymer composites. Hybrid composites consist of interwoven kenaf/jute and kenaf/hemp fibers was prepared by infusion process using epoxy as polymer matrix. Woven kenaf, jute and hemp composites were also prepared for comparison. Both woven and hybrid composites were subjected to three point flexural test. From the result, bending resistance of hybrid kenaf/jute and kenaf/hemp composites was higher compared to their individual fiber. Hybridization with high strength fiber such as kenaf enhanced the capability of jute and hemp fibers to withstand bending load. Interlocking between yarns in woven fabric make pull out fibers nearly impossible and increase the flexural performance of the hybrid composites.

  12. Ductility Performance of Hybrid Fibre Reinforced Concrete

    OpenAIRE

    S. Eswari; P.N. Raghunath; Suguna, K

    2008-01-01

    This study presents a study on the ductility performance of hybrid fibre reinforced concrete. The influence of fibre content on the ductility performance of hybrid fibre reinforced concrete specimens having different fibre volume fractions was investigated. The parameters of investigation included modulus of rupture, ultimate load, service load, ultimate and service load deflection, crack width, energy ductility and deflection ductility. A total of 27 specimens, 100×100×500 mm, were tested to...

  13. High performance carbon nanotube - polymer nanofiber hybrid fabrics

    Science.gov (United States)

    Yildiz, Ozkan; Stano, Kelly; Faraji, Shaghayegh; Stone, Corinne; Willis, Colin; Zhang, Xiangwu; Jur, Jesse S.; Bradford, Philip D.

    2015-10-01

    conductivity. In order to further examine the hybrid fabric properties, they were consolidated under pressure, and also calendered at 70 °C. After calendering, the fabric's strength increased by an order of magnitude due to increased interactions and intermingling with the CNTs. The hybrids are highly efficient as aerosol filters; consolidated hybrid fabrics with a thickness of 20 microns and areal density of only 8 g m-2 exhibited ultra low particulate (ULPA) filter performance. The flexibility of this nanofabrication method allows for the use of many different polymer systems which provides the opportunity for engineering a wide range of nanoscale hybrid materials with desired functionalities. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr02732b

  14. Improvement of electronic circuit and performance of electronic dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Chang, S. Y.; Lee, B. J.; Kim, B. H.; Kim, J. S.; Lee, K. C. [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2001-03-01

    An electronic personnal dosimeter(EPD) adopting a PIN type Silicon semiconductor as a radiation detector has been designed and manufactured. A hybrid type design of electronic circuit for processing a radiation signal has been adopted not only to improve the EPD response to radiation detection but also to reduce a size as well as a weight. The EPD can be independently used as an individual personal dosimeter for exposure monitoring if necessary after setting some variables by operator. The performance of this EPD has been tested and finally accredited by Korea Testing Laboratory(KTL) through a series of performance test under international criteria given in IEC61526 standard on the mechanical, electronical and radiation performance. The EPD reader which can interface an EPD with entrance door for proper access control has been designed and manufactured. A hangul is supported in this EPD reader in operational display menu for the user convenience. 10 refs., 30 figs., 5 tabs. (Author)

  15. SECURED ELECTRONIC VOTING PROTOCOL USING HYBRID CRYPTOSYSTEM

    Directory of Open Access Journals (Sweden)

    KALAICHELVI V

    2013-04-01

    Full Text Available Electronic Voting play a really vital role in the democracy of our life. In this paper, we propose an electronic voting protocol. Our scheme does not require a special voting channel and communication can occur entirely over the current Internet. This method integrates the Internet convenience and cryptology. In the existing protocol the Tallier has to wait until the decryption key is received from the voter. So it will consume lot of time. But, the proposed protocol is based on the hybrid cryptosystem. In this, the ballot is encrypted using faster secret key algorithm and the digital envelope is encrypted using Tallier’s public key. So, the Tallier will decrypt the digital envelope using his own private key to get the secret key and then the encrypted ballot is decrypted using that secret key. So, comparatively the proposed protocol consumes less time. This paper also analyzes the various security issues involved in an electronic voting like security, privacy, authentication, anonymous, uniqueness, accuracy, fairness, efficiency and uncoercibility.

  16. The electronics hybrid of the ATLAS-SCT endcap detector modules

    CERN Document Server

    Ketterer, C

    2004-01-01

    An electronics hybrid has been developed for the ATLAS silicon microstrip tracker endcaps. The high-density interconnect board carries 12 readout ASICs, as well as ASICs for the optical data transmission. Special requirements are that this hybrid has to be double sided, radiation hard, and low mass. A six-layer flexible circuit in copper-polyimide technology has been chosen for this purpose. It is folded around a highly heat conducting carbon-carbon composite substrate to form the rigid double-sided hybrid. Adequate thermal, mechanical, and electrical performance of the hybrid has been demonstrated. The production of the hybrids started in May 2003. (12 refs).

  17. Fast electron dynamics in lower hybrid current drive experiment on HT-7 tokamak

    Institute of Scientific and Technical Information of China (English)

    Shi Yue-Jiang; Kuang Gang-Li; Li Jian-Gang; HT-7 Team; Wan Bao-Nian; Chen Zhong-Yong; Hu Li-Qun; Lin Shi-Yao; Ruan Huai-Lin; Qian Jin-Ping; Zhen Xiang-Jun; Ding Bo-Jiang

    2005-01-01

    The dynamic behaviour of fast electron in lower hybrid current drive (LHCD) experiments is a crucial issue in the sense of enhancing plasma performance. A new hard x-ray diagnostic system on HT-7 allows the investigation of the lower hybrid wave dynamics. The behaviour of fast electron is studied in several kinds of LHCD experiments, including long pulse discharges, high performance discharges and counter-LHCD experiments.

  18. Development of high performance hybrid rocket fuels

    Science.gov (United States)

    Zaseck, Christopher R.

    . In order to examine paraffin/additive combustion in a motor environment, I conducted experiments on well characterized aluminum based additives. In particular, I investigate the influence of aluminum, unpassivated aluminum, milled aluminum/polytetrafluoroethylene (PTFE), and aluminum hydride on the performance of paraffin fuels for hybrid rocket propulsion. I use an optically accessible combustor to examine the performance of the fuel mixtures in terms of characteristic velocity efficiency and regression rate. Each combustor test consumes a 12.7 cm long, 1.9 cm diameter fuel strand under 160 kg/m 2s of oxygen at up to 1.4 MPa. The experimental results indicate that the addition of 5 wt.% 30 mum or 80 nm aluminum to paraffin increases the regression rate by approximately 15% compared to neat paraffin grains. At higher aluminum concentrations and nano-scale particles sizes, the increased melt layer viscosity causes slower regression. Alane and Al/PTFE at 12.5 wt.% increase the regression of paraffin by 21% and 32% respectively. Finally, an aging study indicates that paraffin can protect air and moisture sensitive particles from oxidation. The opposed burner and aluminum/paraffin hybrid rocket experiments show that additives can alter bulk fuel properties, such as viscosity, that regulate entrainment. The general effect of melt layer properties on the entrainment and regression rate of paraffin is not well understood. Improved understanding of how solid additives affect the properties and regression of paraffin is essential to maximize performance. In this document I investigate the effect of melt layer properties on paraffin regression using inert additives. Tests are performed in the optical cylindrical combustor at ˜1 MPa under a gaseous oxygen mass flux of ˜160 kg/m2s. The experiments indicate that the regression rate is proportional to mu0.08rho 0.38kappa0.82. In addition, I explore how to predict fuel viscosity, thermal conductivity, and density prior to testing

  19. Ductility Performance of Hybrid Fibre Reinforced Concrete

    Directory of Open Access Journals (Sweden)

    S. Eswari

    2008-01-01

    Full Text Available This study presents a study on the ductility performance of hybrid fibre reinforced concrete. The influence of fibre content on the ductility performance of hybrid fibre reinforced concrete specimens having different fibre volume fractions was investigated. The parameters of investigation included modulus of rupture, ultimate load, service load, ultimate and service load deflection, crack width, energy ductility and deflection ductility. A total of 27 specimens, 100×100×500 mm, were tested to study the above parameters. The specimens incorporated 0.0 to 2.0% volume fraction of polyolefin and steel fibres in different proportions. The ductility performance of hybrid fibre reinforced concrete specimens was compared with that of plain concrete. The test results show that addition of 2.0% by volume of hybrid fibres improves the ductility performance appreciably. An adaptive Neuro-Fuzzy based model has been proposed to predict the ductility performance characteristics. A reasonably close agreement has been obtained between the experimental and predicted results.

  20. Electron imaging with Medipix2 hybrid pixel detector

    CERN Document Server

    McMullan, G; Chen, S; Henderson, R; Llopart, X; Summerfield, C; Tlustos, L; Faruqi, A R

    2007-01-01

    The electron imaging performance of Medipix2 is described. Medipix2 is a hybrid pixel detector composed of two layers. It has a sensor layer and a layer of readout electronics, in which each 55 μm×55 μm pixel has upper and lower energy discrimination and MHz rate counting. The sensor layer consists of a 300 μm slab of pixellated monolithic silicon and this is bonded to the readout chip. Experimental measurement of the detective quantum efficiency, DQE(0) at 120 keV shows that it can reach 85% independent of electron exposure, since the detector has zero noise, and the DQE(Nyquist) can reach 35% of that expected for a perfect detector (4/π2). Experimental measurement of the modulation transfer function (MTF) at Nyquist resolution for 120 keV electrons using a 60 keV lower energy threshold, yields a value that is 50% of that expected for a perfect detector (2/π). Finally, Monte Carlo simulations of electron tracks and energy deposited in adjacent pixels have been performed and used to calculate expected v...

  1. Electronic heat current rectification in hybrid superconducting devices

    Energy Technology Data Exchange (ETDEWEB)

    Fornieri, Antonio, E-mail: antonio.fornieri@sns.it; Giazotto, Francesco, E-mail: francesco.giazotto@sns.it [NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, I-56127 Pisa (Italy); Martínez-Pérez, María José [Physikalisches Institut - Experimentalphysik II Universität Tübingen, D-72076 Tübingen (Germany)

    2015-05-15

    In this work, we review and expand recent theoretical proposals for the realization of electronic thermal diodes based on tunnel-junctions of normal metal and superconducting thin films. Starting from the basic rectifying properties of a single hybrid tunnel junction, we will show how the rectification efficiency can be largely increased by combining multiple junctions in an asymmetric chain of tunnel-coupled islands. We propose three different designs, analyzing their performance and their potential advantages. Besides being relevant from a fundamental physics point of view, this kind of devices might find important technological application as fundamental building blocks in solid-state thermal nanocircuits and in general-purpose cryogenic electronic applications requiring energy management.

  2. Hybrid gate dielectric materials for unconventional electronic circuitry.

    Science.gov (United States)

    Ha, Young-Geun; Everaerts, Ken; Hersam, Mark C; Marks, Tobin J

    2014-04-15

    Recent advances in semiconductor performance made possible by organic π-electron molecules, carbon-based nanomaterials, and metal oxides have been a central scientific and technological research focus over the past decade in the quest for flexible and transparent electronic products. However, advances in semiconductor materials require corresponding advances in compatible gate dielectric materials, which must exhibit excellent electrical properties such as large capacitance, high breakdown strength, low leakage current density, and mechanical flexibility on arbitrary substrates. Historically, conventional silicon dioxide (SiO2) has dominated electronics as the preferred gate dielectric material in complementary metal oxide semiconductor (CMOS) integrated transistor circuitry. However, it does not satisfy many of the performance requirements for the aforementioned semiconductors due to its relatively low dielectric constant and intransigent processability. High-k inorganics such as hafnium dioxide (HfO2) or zirconium dioxide (ZrO2) offer some increases in performance, but scientists have great difficulty depositing these materials as smooth films at temperatures compatible with flexible plastic substrates. While various organic polymers are accessible via chemical synthesis and readily form films from solution, they typically exhibit low capacitances, and the corresponding transistors operate at unacceptably high voltages. More recently, researchers have combined the favorable properties of high-k metal oxides and π-electron organics to form processable, structurally well-defined, and robust self-assembled multilayer nanodielectrics, which enable high-performance transistors with a wide variety of unconventional semiconductors. In this Account, we review recent advances in organic-inorganic hybrid gate dielectrics, fabricated by multilayer self-assembly, and their remarkable synergy with unconventional semiconductors. We first discuss the principals and functional

  3. Mixed protonic and electronic conductors hybrid oxide synaptic transistors

    Science.gov (United States)

    Fu, Yang Ming; Zhu, Li Qiang; Wen, Juan; Xiao, Hui; Liu, Rui

    2017-05-01

    Mixed ionic and electronic conductor hybrid devices have attracted widespread attention in the field of brain-inspired neuromorphic systems. Here, mixed protonic and electronic conductor (MPEC) hybrid indium-tungsten-oxide (IWO) synaptic transistors gated by nanogranular phosphorosilicate glass (PSG) based electrolytes were obtained. Unique field-configurable proton self-modulation behaviors were observed on the MPEC hybrid transistor with extremely strong interfacial electric-double-layer effects. Temporally coupled synaptic plasticities were demonstrated on the MPEC hybrid IWO synaptic transistor, including depolarization/hyperpolarization, synaptic facilitation and depression, facilitation-stead/depression-stead behaviors, spiking rate dependent plasticity, and high-pass/low-pass synaptic filtering behaviors. MPEC hybrid synaptic transistors may find potential applications in neuron-inspired platforms.

  4. Hybrid ventilation systems and high performance buildings

    Energy Technology Data Exchange (ETDEWEB)

    Utzinger, D.M. [Wisconsin Univ., Milwaukee, WI (United States). School of Architecture and Urban Planning

    2009-07-01

    This paper described hybrid ventilation design strategies and their impact on 3 high performance buildings located in southern Wisconsin. The Hybrid ventilation systems combined occupant controlled natural ventilation with mechanical ventilation systems. Natural ventilation was shown to provide adequate ventilation when appropriately designed. Proper control integration of natural ventilation into hybrid systems was shown to reduce energy consumption in high performance buildings. This paper also described the lessons learned from the 3 buildings. The author served as energy consultant on all three projects and had the responsibility of designing and integrating the natural ventilation systems into the HVAC control strategy. A post occupancy evaluation of building energy performance has provided learning material for architecture students. The 3 buildings included the Schlitz Audubon Nature Center completed in 2003; the Urban Ecology Center completed in 2004; and the Aldo Leopold Legacy Center completed in 2007. This paper included the size, measured energy utilization intensity and percentage of energy supplied by renewable solar power and bio-fuels on site for each building. 6 refs., 2 tabs., 6 figs.

  5. Hybrid nanostructured materials for high-performance electrochemical capacitors

    KAUST Repository

    Yu, Guihua

    2013-03-01

    The exciting development of advanced nanostructured materials has driven the rapid growth of research in the field of electrochemical energy storage (EES) systems which are critical to a variety of applications ranging from portable consumer electronics, hybrid electric vehicles, to large industrial scale power and energy management. Owing to their capability to deliver high power performance and extremely long cycle life, electrochemical capacitors (ECs), one of the key EES systems, have attracted increasing attention in the recent years since they can complement or even replace batteries in the energy storage field, especially when high power delivery or uptake is needed. This review article describes the most recent progress in the development of nanostructured electrode materials for EC technology, with a particular focus on hybrid nanostructured materials that combine carbon based materials with pseudocapacitive metal oxides or conducting polymers for achieving high-performance ECs. This review starts with an overview of EES technologies and the comparison between various EES systems, followed by a brief description of energy storage mechanisms for different types of EC materials. This review emphasizes the exciting development of both hybrid nanomaterials and novel support structures for effective electrochemical utilization and high mass loading of active electrode materials, both of which have brought the energy density of ECs closer to that of batteries while still maintaining their characteristic high power density. Last, future research directions and the remaining challenges toward the rational design and synthesis of hybrid nanostructured electrode materials for next-generation ECs are discussed. © 2012 Elsevier Ltd.

  6. Electron transport in a mesoscopic superconducting ferromagnetic hybrid conductor

    Energy Technology Data Exchange (ETDEWEB)

    Giroud, M.; Hasselbach, K.; Courtois, H.; Pannetier, B. [Centre de Recherche sur les Tres Basses Temperatures, CNRS, 38 - Grenoble (France); Mailly, D. [Laboratoire de Photonique et de Nanostructures, 91 - Marcoussis (France)

    2003-01-01

    We present electrical transport experiments performed on submicron hybrid devices made of a ferromagnetic conductor (Co) and a superconducting (Al) electrode. The sample was patterned in order to separate the contributions of the Co conductor and of the Co-Al interface. We observed a strong influence of the Al electrode superconductivity on the resistance of the Co conductor. This effect is large only when the interface is highly transparent. We characterized the dependence of the observed resistance decrease on temperature, bias current and magnetic field. As the differential resistance of the ferromagnet exhibits a non-trivial asymmetry, we claim that the magnetic domain structure plays an important role in the electron transport properties of superconducting / ferromagnetic conductors. (authors)

  7. Hybrid simulation of electron cyclotron resonance heating

    CERN Document Server

    Ropponen, T; Suominen, P; Koponen, T K; Kalvas, T; Koivisto, H

    2008-01-01

    Electron Cyclotron Resonance (ECR) heating is a fundamentally important aspect in understanding the physics of Electron Cyclotron Resonance Ion Sources (ECRIS). Absorption of the radio frequency (RF) microwave power by electron heating in the resonance zone depends on many parameters including frequency and electric field strength of the microwave, magnetic field structure and electron and ion density profiles. ECR absorption has been studied in the past by e.g. modelling electric field behaviour in the resonance zone and its near proximity. This paper introduces a new ECR heating code that implements damping of the microwave power in the vicinity of the resonance zone, utilizes electron density profiles and uses right hand circularly polarized (RHCP) electromagnetic waves to simulate electron heating in ECRIS plasma.

  8. Hybrid simulation of electron cyclotron resonance heating

    Energy Technology Data Exchange (ETDEWEB)

    Ropponen, T. [Department of Physics, University of Jyvaeskylae, P.O. Box 35, FI-40014 (Finland)], E-mail: tommi.ropponen@phys.jyu.fi; Tarvainen, O. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Suominen, P. [CERN Geneve 23, CH-1211 (Switzerland); Koponen, T.K. [Department of Physics, University of Jyvaeskylae, Nanoscience Center, P.O. Box 35, FI-40014 (Finland); Kalvas, T.; Koivisto, H. [Department of Physics, University of Jyvaeskylae, P.O. Box 35, FI-40014 (Finland)

    2008-03-11

    Electron Cyclotron Resonance (ECR) heating is a fundamentally important aspect in understanding the physics of Electron Cyclotron Resonance Ion Sources (ECRIS). Absorption of the radio frequency (RF) microwave power by electron heating in the resonance zone depends on many parameters including frequency and electric field strength of the microwave, magnetic field structure and electron and ion density profiles. ECR absorption has been studied in the past by e.g. modelling electric field behaviour in the resonance zone and its near proximity. This paper introduces a new ECR heating code that implements damping of the microwave power in the vicinity of the resonance zone, utilizes electron density profiles and uses right hand circularly polarized (RHCP) electromagnetic waves to simulate electron heating in ECRIS plasma.

  9. Rechargeable Mg battery cathode TiS3 with d-p orbital hybridized electronic structures

    Science.gov (United States)

    Taniguchi, Kouji; Gu, Yunpeng; Katsura, Yukari; Yoshino, Takafumi; Takagi, Hidenori

    2016-01-01

    Rechargeable performance is realized in Mg batteries using a TiS3 cathode without the nanometer-scale downsizing of electrode particles. The specific capacity is about 80 mAh/g for the first 50 cycles at room temperature. This observed specific capacity is comparable to that of the prototype cathode for Mg batteries. First-principles calculation indicates that TiS3 is a semiconductor with d-p orbital hybridized electronic structures around the Fermi level. The reversible electrode performance is likely assisted by the delocalized electronic distribution over metal-ligand units through d-p orbital hybridization.

  10. Technique for Measuring Hybrid Electronic Component Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Green, C.C.; Hernandez, C.L.; Hosking, F.M.; Robinson, D.; Rutherford, B.; Uribe, F.

    1999-01-01

    Materials compatibility studies of aged, engineered materials and hardware are critical to understanding and predicting component reliability, particularly for systems with extended stockpile life requirements. Nondestructive testing capabilities for component reliability would significantly enhance lifetime predictions. For example, if the detection of crack propagation through a solder joint can be demonstrated, this technique could be used to develop baseline information to statistically determine solder joint lifelengths. This report will investigate high frequency signal response techniques for nondestructively evaluating the electrical behavior of thick film hybrid transmission lines.

  11. Mechanical performance of oil palm empty fruit bunches/jute fibres reinforced epoxy hybrid composites

    Energy Technology Data Exchange (ETDEWEB)

    Jawaid, M. [School of Industrial Technology, Universiti Sains Malaysia, 11800 Penang (Malaysia); Abdul Khalil, H.P.S., E-mail: akhalilhps@gmail.com [School of Industrial Technology, Universiti Sains Malaysia, 11800 Penang (Malaysia); Abu Bakar, A. [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia)

    2010-11-15

    Research highlights: {yields} Hybrid composites constituents of natural fibres show good mechanical performances. {yields} Hybridization with 20% jute fibre gives rise to sufficient modulus to composites. {yields} Outer or core material affect mechanical performance of hybrid composites. {yields} Impact strength of pure EFB composite is higher than hybrid composites. - Abstract: Oil palm empty fruit bunches (EFB)/jute fibre reinforced epoxy hybrid composites with different sequence of fibre mat arrangement such as EFB/jute/EFB and jute/EFB/jute were fabricated by hand lay-up method. The effect of layering patterns on the mechanical performance of the composites was studied. The hybrid composites are intended for engineering applications as an alternative to synthetic fibre composites. Mechanical performance of hybrid composites were evaluated and compared with the pure EFB, pure jute composites and neat epoxy using flexural and impact testing. The flexural properties of hybrid composite is higher than that of pure EFB composite with respect to the weight fraction of fibre, where as the impact strength of pure EFB composite is much higher than those of hybrid composites. The flexural results were interpreted using sandwich theory. The fracture surface morphology of the impact testing samples of the hybrid composites was performed by scanning electron microscopy (SEM).

  12. Hybrid electronics and electrochemistry with conjugated polymers.

    Science.gov (United States)

    Inganäs, Olle

    2010-07-01

    In this critical review, we discuss the history and development of polymer devices wherein manipulation of the electronic conductivity by electrochemical redox processes in a conjugated polymer is used to form new functions. The devices employed are an electrochemical transistor, an electrolyte-gated field-effect transistor and light-emitting electrochemical cells, all of which combine doping/undoping of a conjugated polymer with modification of electronic transport (130 references).

  13. Hybrid Modeling Improves Health and Performance Monitoring

    Science.gov (United States)

    2007-01-01

    Scientific Monitoring Inc. was awarded a Phase I Small Business Innovation Research (SBIR) project by NASA's Dryden Flight Research Center to create a new, simplified health-monitoring approach for flight vehicles and flight equipment. The project developed a hybrid physical model concept that provided a structured approach to simplifying complex design models for use in health monitoring, allowing the output or performance of the equipment to be compared to what the design models predicted, so that deterioration or impending failure could be detected before there would be an impact on the equipment's operational capability. Based on the original modeling technology, Scientific Monitoring released I-Trend, a commercial health- and performance-monitoring software product named for its intelligent trending, diagnostics, and prognostics capabilities, as part of the company's complete ICEMS (Intelligent Condition-based Equipment Management System) suite of monitoring and advanced alerting software. I-Trend uses the hybrid physical model to better characterize the nature of health or performance alarms that result in "no fault found" false alarms. Additionally, the use of physical principles helps I-Trend identify problems sooner. I-Trend technology is currently in use in several commercial aviation programs, and the U.S. Air Force recently tapped Scientific Monitoring to develop next-generation engine health-management software for monitoring its fleet of jet engines. Scientific Monitoring has continued the original NASA work, this time under a Phase III SBIR contract with a joint NASA-Pratt & Whitney aviation security program on propulsion-controlled aircraft under missile-damaged aircraft conditions.

  14. Photoinduced Reductive Electron Transfer in LNA:DNA Hybrids

    DEFF Research Database (Denmark)

    Wenge, Ulrike; Wengel, Jesper; Wagenknecht, Hans-Achim

    2012-01-01

    Lock it, but not too much: LNA units (locked or bridging nucleic acids) in LNA:DNA hybrids lead to a negative effect on electron transfer (ET), but they also force the nucleic acid structure in the A-type double helix, which allows a better base stacking than the normal B-type and thus positively...... influences the ET. This result is significant for the design of nucleic acids of molecular electronics....

  15. Hybrid LC filter for power electronic drives. Theory and implementation

    Energy Technology Data Exchange (ETDEWEB)

    Dzhankhotov, V.

    2009-07-01

    Power electronic converter drives use, for the sake of high efficiency, pulse-width modulation that results in sequences of high-voltage high-frequency steep-edged pulses. Such a signal contains a set of high harmonics not required for control purposes. Harmonics cause reflections in the cable between the motor and the inverter leading to faster winding insulation ageing. Bearing failures and problems with electromagnetic compatibility may also result. Electrical du/dt filters provide an effective solution to problems caused by pulse-width modulation, thereby increasing the performance and service life of the electrical machines. It is shown that RLC filters effectively decrease the reflection phenomena in the cable. Improved (simple, but effective) solutions are found for both differential- and common-mode signals; these solutions use a galvanic connection between the RLC filter star point and the converter DC link. Foil chokes and film capacitors are among the most widely used components in high-power applications. In actual applications they can be placed in different parts of the cabinet. This fact complicates the arrangement of the cabinet and decreases the reliability of the system. In addition, the inductances of connection wires may prevent filtration at high frequencies. This thesis introduces a new hybrid LC filter that uses a natural capacitance between the turns of the foil choke based on integration of an auxiliary layer into it. The main idea of the hybrid LC filter results from the fact that both the foil choke and the film capacitors have the same roll structure. Moreover, the capacitance between the turns ('intra capacitance') of the foil inductors is the reason for the deterioration of their properties at high frequencies. It is shown that the proposed filter has a natural cancellation of the intra capacitance. A hybrid LC filter may contain two or more foil layers isolated from each other and coiled on a core. The core material can be

  16. Electrostatic electron cyclotron instabilities near the upper hybrid layer due to electron ring distributions

    Science.gov (United States)

    Eliasson, B.; Speirs, D. C.; Daldorff, L. K. S.

    2016-09-01

    A theoretical study is presented of the electrostatic electron cyclotron instability involving Bernstein modes in a magnetized plasma. The presence of a tenuous thermal ring distribution in a Maxwellian plasma decreases the frequency of the upper hybrid branch of the electron Bernstein mode until it merges with the nearest lower branch with a resulting instability. The instability occurs when the upper hybrid frequency is somewhat above the third, fourth, and higher electron cyclotron harmonics, and gives rise to a narrow spectrum of waves around the electron cyclotron harmonic nearest to the upper hybrid frequency. For a tenuous cold ring distribution together with a Maxwellian distribution an instability can take place also near the second electron cyclotron harmonic. Noise-free Vlasov simulations are used to assess the theoretical linear growth-rates and frequency spectra, and to study the nonlinear evolution of the instability. The relevance of the results to laboratory and ionospheric heating experiments is discussed.

  17. Electronic properties of hybrid metal-discotic liquid crystal nanostructures

    Science.gov (United States)

    Kelsall, R. W.; Pecchia, A.; Bourlange, A.; Movaghar, B.; Evans, S. D.; Hickey, B. J.; Boden, N.

    2003-04-01

    A new class of hybrid organic/inorganic nanostructures, comprising self-organised discotic liquid crystal layers deposited on ultrathin metal films, has been investigated both experimentally and theoretically. Calculations show that the periodic self-organised molecular layer gives rise to a new, hybrid electronic bandstructure, resulting in modulation of the metal film conductivity. In situ conductivity measurements during deposition of such self-organised layers confirm that the metal film conductivity is altered. Theoretical modeling also shows that the AC conductivity should show structure related to the carrier trapping and one-dimensional transport features of the self-organised layer.

  18. Agronomic Performance of Two Tetraploid Hybrid Plantains in Ghana

    OpenAIRE

    Beloved Mensah Dzomeku; Asieduwa Agnes Ankomah; Solomon Kodjo Darkey

    2009-01-01

    Field performance of two IITA plantain hybrids (‘PITA-1’, ‘PITA-4’) were assessed at two locations in Ghana alongside two local landraces (False Horn ‘Brodeyuo’, Intermediate French ‘Oniaba’) and a hybrid cultivar ‘Apem Hemaa’ (‘FHIA-21’). The objective of the study was to identify high yielding and disease resistant hybrids for growers in Ghana. The hybrids were evaluated for their agronomic performance and yield, tolerance to Black Sigatoka disease, number of functional leaves at flowering ...

  19. Design and Ballistic Performance of Hybrid Composite Laminates

    Science.gov (United States)

    Ćwik, Tomasz K.; Iannucci, Lorenzo; Curtis, Paul; Pope, Dan

    2016-10-01

    This paper presents an initial design assessment of a series of novel, cost-effective, and hybrid composite materials for applications involving high velocity impacts. The proposed hybrid panels were designed in order to investigate various physical phenomenon occurring during high velocity impact on compliant laminates from a previous study on Dyneema® and Spectra®. In the first, screening phase of the study twenty different hybrid composite laminates were impacted with 20 mm Fragment Simulating Projectiles at 1 km/s striking velocity. The best performing concepts were put forward to phase II with other hybrid concepts involving shear thickening fluids, commonly used in low velocity impacts. The results indicated that it is possible to design hybrid laminates of similar ballistic performance as the reference Dyneema® laminate, but with lower material costs. The optimal hybrid concept involves a fibre reinforced Polypropylene front and a Dyneema® backing.

  20. Hybridized electromagnetic-triboelectric nanogenerator for scavenging biomechanical energy for sustainably powering wearable electronics.

    Science.gov (United States)

    Zhang, Kewei; Wang, Xue; Yang, Ya; Wang, Zhong Lin

    2015-01-01

    We report a hybridized electromagnetic-triboelectric nanogenerator for highly efficient scavenging of biomechanical energy to sustainably power wearable electronics by human walking. Based on the effective conjunction of triboelectrification and electromagnetic induction, the hybridized nanogenerator, with dimensions of 5 cm × 5 cm × 2.5 cm and a light weight of 60 g, integrates a triboelectric nanogenerator (TENG) that can deliver a peak output power of 4.9 mW under a loading resistance of 6 MΩ and an electromagnetic generator (EMG) that can deliver a peak output power of 3.5 mW under a loading resistance of 2 kΩ. The hybridized nanogenerator exhibits a good stability for the output performance and a much better charging performance than that of an individual energy-harvesting unit (TENG or EMG). Furthermore, the hybridized nanogenerator integrated in a commercial shoe has been utilized to harvest biomechanical energy induced by human walking to directly light up tens of light-emitting diodes in the shoe and sustainably power a smart pedometer for reading the data of a walking step, distance, and energy consumption. A wireless pedometer driven by the hybrid nanogenerator can work well to send the walking data to an iPhone under the distance of 25 m. This work pushes forward a significant step toward energy harvesting from human walking and its potential applications in sustainably powering wearable electronics.

  1. Hybrid planar free-electron maser in the magnetoresonance regime

    Directory of Open Access Journals (Sweden)

    Vitaliy A. Goryashko

    2009-10-01

    Full Text Available We study the operation regime of a hybrid planar free-electron maser (FEM amplifier near the magnetoresonant value of the uniform longitudinal (guide magnetic field. Using analytical expressions for individual test electron trajectories and normal frequencies of their three-dimensional oscillations in the magnetostatic field of the hybrid planar FEM, an analytical condition of chaotization of motion is established and shown to be given by the Chirikov resonance-overlap criterion applied to the normal undulator and cyclotron frequencies with respect to the coupling induced by the undulator magnetic field. It is also shown analytically that, in spite of the well-known drop for the exact magnetoresonance, the gain attains its maximal value in the zone of regular dynamics slightly above the magnetoresonant value of the guide magnetic field. Under the condition of undulator resonance, it is practically independent of the amplitude of the undulator magnetic field and the wavelength of amplified signal. To account for space-charge effects, we propose a theoretical model of a weakly relativistic FEM, which accommodates not only potential but also rotational parts of the nonradiated electromagnetic field of a moving charged particle. It turns out that the rotational part of nonradiated field diminishes the defocusing influence of the potential part on the beam bunching. Numeric simulation of the nonlinear stage of amplification is fulfilled, taking into consideration adiabatic entrance of the electron beam to the interaction region and initial electron velocity spread. We find that nonradiated field and initial electron velocity spread do not influence essentially the efficiency of hybrid planar FEM amplification if parameters of the beam-microwave interaction correspond to the operational regime in the zone of regular dynamics near the magnetoresonance.

  2. Electronic structure of hybrid interfaces for polymer-based electronics.

    Science.gov (United States)

    Fahlman, M; Crispin, A; Crispin, X; Henze, S K M; de Jong, M P; Osikowicz, W; Tengstedt, C; Salaneck, W R

    2007-05-08

    The fundamentals of the energy level alignment at anode and cathode electrodes in organic electronics are described. We focus on two different models that treat weakly interacting organic/metal (and organic/organic) interfaces: the induced density of interfacial states model and the so-called integer charge transfer model. The two models are compared and evaluated, mainly using photoelectron spectroscopy data of the energy level alignment of conjugated polymers and molecules at various organic/metal and organic/organic interfaces. We show that two different alignment regimes are generally observed: (i) vacuum level alignment, which corresponds to the lack of vacuum level offsets (Schottky-Mott limit) and hence the lack of charge transfer across the interface, and (ii) Fermi level pinning where the resulting work function of an organic/metal and organic/organic bilayer is independent of the substrate work function and an interface dipole is formed due to charge transfer across the interface. We argue that the experimental results are best described by the integer charge transfer model which predicts the vacuum level alignment when the substrate work function is above the positive charge transfer level and below the negative charge transfer level of the conjugated material. The model further predicts Fermi level pinning to the positive (negative) charge transfer level when the substrate work function is below (above) the positive (negative) charge transfer level. The nature of the integer charge transfer levels depend on the materials system: for conjugated large molecules and polymers, the integer charge transfer states are polarons or bipolarons; for small molecules' highest occupied and lowest unoccupied molecular orbitals and for crystalline systems, the relevant levels are the valence and conduction band edges. Finally, limits and further improvements to the integer charge transfer model are discussed as well as the impact on device design.

  3. Agronomic Performance of Two Tetraploid Hybrid Plantains in Ghana

    Directory of Open Access Journals (Sweden)

    Beloved Mensah Dzomeku

    2009-12-01

    Full Text Available Field performance of two IITA plantain hybrids (‘PITA-1’, ‘PITA-4’ were assessed at two locations in Ghana alongside two local landraces (False Horn ‘Brodeyuo’, Intermediate French ‘Oniaba’ and a hybrid cultivar ‘Apem Hemaa’ (‘FHIA-21’. The objective of the study was to identify high yielding and disease resistant hybrids for growers in Ghana. The hybrids were evaluated for their agronomic performance and yield, tolerance to Black Sigatoka disease, number of functional leaves at flowering and at harvest, crop cycle, plant height and pseudostem girth. The results showed that the hybrids were tolerant/resistant to the Black Sigatoka (Mycosphaerella fi jiensis disease with high number of functional leaves at flowering and at harvest. This characteristic of the hybrids was an important feature that could fit well into the smallholder cropping system. The crop cycles were comparable to that of ‘False Horn’ plantains. The yield performance of the hybrids was better compared to the landraces. The number of hands per bunch produced by the hybrids was also higher than those of the landraces except the intermediate French plantain (‘Oniaba’. The finger lengths of the IITA hybrids were however shorter compared to the landraces and this could hinder their acceptance by consumers.

  4. Performance of pearl millet hybrids under arid conditions

    Directory of Open Access Journals (Sweden)

    V.K. Manga, and Arun Kumar

    2011-09-01

    Full Text Available Sixteen male-sterile lines of pearl millet (Pennisetum glaucum (L. R. Br. found promising at CAZRI, Jodhpur were crossed with nine diverse restorers from different sources in this region, in a line x tester fashion to develop 144 hybrid combinations, with the objective to identify suitable A lines, R lines and hybrid combinations for arid Rajasthan. These hybrids were evaluated at three different locations in western Rajasthan (Tinwari, Pali and Jodhpur during the rainy season of 2003. Eighteen promising hybrids based upon their performance over locations during 2003, were again evaluated in larger plots during the rainy season of 2004. Considering grain yield over all the five locations during the two seasons 2003 and 2004, ten high yielding hybrids were identified. Among these hybrids grain yield ranged from 1932 kg/ha to 2293 kg/ha, and flowering time from 43 to 48 days. The highest yielding hybrid was ICMA 96111 x RIB-3135-18 followed by ICMA 98333 x RIB-3135-18, ICMA 98222 x CZI 9621, ICMA 98004 x RIB-3135-18, ICMA 97555 x RIB-3135-18 and ICMA 95555 x H 77/833-2. It was observed that the restorer lines RIB-3135-18, CZI 9621, H77/833-2, CZI 1676-2, MIR 97171 and ICMR 356 gave high yielding hybrids. Similarly male sterile lines, ICMA 98222, ICMA 97555 and ICMA 98004 were involved in promising hybrid combinations. The hybrid ICMA 98222 x CZI 9621, which was one of the top five high yielding hybrids, ranked first in a multilocation trial conducted during the rainy season of 2005, at Jodhpur, Bawal, Durgapura and Bikaner, representing extreme arid conditions. This hybrid again recorded 12.8% and 6.6% higher grain yield over national checks GHB 538 and ICMH 356 respectively in Initial hybrid trial 2007, and was promoted to the Advance Hybrid and Population Trial for Kharif 2008.

  5. Ablation Performance of a Novel Super-hybrid Composite

    Institute of Scientific and Technical Information of China (English)

    Jun QIU; Xiaoming CAO; Chong TIAN; Jinsong ZHANG

    2005-01-01

    A novel super-hybrid composite (NSHC) was boron-modified phenolic resin (BPR) with three-dimensional reticulated SiC ceramic (3DRC) and high silica fibers. Ablation performance of the NSHC was studied. The results show that the linear ablation rate of NSHC was lower than that of pure BPR and the high silica/BPR composite. Its linear ablation rate is 1/17 of the high silica/BPR. Mass ablation rate of the NSHC is very close to that of the pure BPR and the high silica/BPR composite. Scanning electron microscope (SEM) analysis indicates that 3DRC has scarcely changed its shape at the ablation temperature. Its special reticulated structure can restrict the materials deformation and prevent high velocity heat flow from eroding the surface of the materials largely and thus increase ablation resistance of the NSHC.

  6. High performance hybrid magnetic structure for biotechnology applications

    Science.gov (United States)

    Humphries, David E [El Cerrito, CA; Pollard, Martin J [El Cerrito, CA; Elkin, Christopher J [San Ramon, CA

    2009-02-03

    The present disclosure provides a high performance hybrid magnetic structure made from a combination of permanent magnets and ferromagnetic pole materials which are assembled in a predetermined array. The hybrid magnetic structure provides means for separation and other biotechnology applications involving holding, manipulation, or separation of magnetic or magnetizable molecular structures and targets. Also disclosed are further improvements to aspects of the hybrid magnetic structure, including additional elements and for adapting the use of the hybrid magnetic structure for use in biotechnology and high throughput processes.

  7. Role of Microstructure in the Electron-Hole Interaction of Hybrid Lead-Halide Perovskites

    OpenAIRE

    Grancini, Giulia; Srimath Kandada, Ajay Ram; Frost, Jarvist M.; Barker, Alex J; Bastiani, Michele; Gandini, Marina; Marras, Sergio; Lanzani, Guglielmo; Walsh, Aron; Petrozza, Annamaria

    2015-01-01

    Solar cells based on hybrid inorganic-organic halide perovskites have demonstrated high power conversion efficiencies in a range of architectures. The existence and stability of bound electron-hole pairs in these materials, and their role in the exceptional performance of optoelectronic devices, remains a controversial issue. Here we demonstrate, through a combination of optical spectroscopy and multiscale modeling as a function of the degree of polycrystallinity and temperature, that the ele...

  8. Hybrid [5]Radialenes with Bispyrroloheteroles: New Electron-Donating Units.

    Science.gov (United States)

    Higashino, Tomohiro; Imahori, Hiroshi

    2015-09-14

    Bispyrroloheteroles have been synthesized to address their intrinsic structural, optical, and electrochemical properties. The X-ray crystal structures and calculated natural bond orbital (NBO) bond orders unambiguously demonstrated the existence of a two pyrrole-fused five-membered ring with short exocyclic C-C double bonds and long endocyclic C-C single bonds, supporting that the bispyrroloheteroles are rare examples of structurally characterized hybrid [5]radialenes. The bispyrroloheteroles were found to act as an electron-donating unit, which would be fascinating for the rational design of new charge-transporting and donor-acceptor photovoltaic materials as well as versatile charge-transfer complexes.

  9. Transmission electron microscopy of unstained hybrid Au nanoparticles capped with PPAA (plasma-poly-allylamine)

    DEFF Research Database (Denmark)

    Gontard, Lionel C.; Fernández, Asunción; Dunin-Borkowski, Rafal E.;

    2014-01-01

    Hybrid (organic shell-inorganic core) nanoparticles have important applications in nanomedicine. Although the inorganic components of hybrid nanoparticles can be characterized readily using conventional transmission electron microscopy (TEM) techniques, the structural and chemical arrangement of ...

  10. Structural and electronic properties of hybrid silicon-germanium nanosheets

    Directory of Open Access Journals (Sweden)

    F. L. Pérez Sánchez

    2014-12-01

    Full Text Available Using first principles molecular calculations, based on the Density Functional Theory (DFT, structural and electronic properties of hybrid graphene—like silicon—germanium circular nanosheets of hexagonal symmetry are investigated. The exchange—correlation functional of Perdew—Wang (PW in the local spin density approximation (LSDA based on the pseudopotentials of Dolg—Bergnre is applied. The finite extension nanosheets are represented by the CnHm—like cluster model with mono—hydrogenated armchair edges. Changes of the physicochemical properties were analyzed to learn on the chemical composition. We have obtained that the corrugation of the hybrid nanosheets is maintained (with respect to the pristine nanosheets of Ge and Si and is more pronounced when there is a high percentage of germanium. Moreover, hybrid nanosheets have ionic bonds (polarity in the interval from 0.18 to 0.77 D and exhibit a semimetal behavior. Three types of chemical compositions are considered: 1 the one—one relationship, 2 formation of Ge dimers and 3 formation of Ge hexagons. In each case it is observed an increase in the chemical reactivity. Finally, analyzing the work function we conclude that in cases 1 and 2 the chemical compositions improve the efficiency of the field emission and thereby they could expand the scope of nanotechnology applications.

  11. Photoionization of few electron systems with a hybrid Coupled Channels approach

    CERN Document Server

    Majety, Vinay Pramod; Scrinzi, Armin

    2014-01-01

    We present the hybrid anti-symmetrized coupled channels method for the calculation of fully differential photo-electron spectra of multi-electron atoms and small molecules interacting with strong laser fields. The method unites quantum chemical few-body electronic structure with strong-field dynamics by solving the time dependent Schr\\"odinger equation in a fully anti-symmetrized basis composed of multi-electron states from quantum chemistry and a one-electron numerical basis. Photoelectron spectra are obtained via the time dependent surface flux (tSURFF) method. Performance and accuracy of the approach are demonstrated for spectra from the helium and berryllium atoms and the hydrogen molecule in linearly polarized laser fields at wavelength from 21 nm to 400 nm. At long wavelengths, helium and the hydrogen molecule at equilibrium inter-nuclear distance can be approximated as single channel systems whereas beryllium needs a multi-channel description.

  12. Electron-phonon coupling in hybrid lead halide perovskites

    Science.gov (United States)

    Wright, Adam D.; Verdi, Carla; Milot, Rebecca L.; Eperon, Giles E.; Pérez-Osorio, Miguel A.; Snaith, Henry J.; Giustino, Feliciano; Johnston, Michael B.; Herz, Laura M.

    2016-05-01

    Phonon scattering limits charge-carrier mobilities and governs emission line broadening in hybrid metal halide perovskites. Establishing how charge carriers interact with phonons in these materials is therefore essential for the development of high-efficiency perovskite photovoltaics and low-cost lasers. Here we investigate the temperature dependence of emission line broadening in the four commonly studied formamidinium and methylammonium perovskites, HC(NH2)2PbI3, HC(NH2)2PbBr3, CH3NH3PbI3 and CH3NH3PbBr3, and discover that scattering from longitudinal optical phonons via the Fröhlich interaction is the dominant source of electron-phonon coupling near room temperature, with scattering off acoustic phonons negligible. We determine energies for the interacting longitudinal optical phonon modes to be 11.5 and 15.3 meV, and Fröhlich coupling constants of ~40 and 60 meV for the lead iodide and bromide perovskites, respectively. Our findings correlate well with first-principles calculations based on many-body perturbation theory, which underlines the suitability of an electronic band-structure picture for describing charge carriers in hybrid perovskites.

  13. Electron-phonon coupling in hybrid lead halide perovskites.

    Science.gov (United States)

    Wright, Adam D; Verdi, Carla; Milot, Rebecca L; Eperon, Giles E; Pérez-Osorio, Miguel A; Snaith, Henry J; Giustino, Feliciano; Johnston, Michael B; Herz, Laura M

    2016-05-26

    Phonon scattering limits charge-carrier mobilities and governs emission line broadening in hybrid metal halide perovskites. Establishing how charge carriers interact with phonons in these materials is therefore essential for the development of high-efficiency perovskite photovoltaics and low-cost lasers. Here we investigate the temperature dependence of emission line broadening in the four commonly studied formamidinium and methylammonium perovskites, HC(NH2)2PbI3, HC(NH2)2PbBr3, CH3NH3PbI3 and CH3NH3PbBr3, and discover that scattering from longitudinal optical phonons via the Fröhlich interaction is the dominant source of electron-phonon coupling near room temperature, with scattering off acoustic phonons negligible. We determine energies for the interacting longitudinal optical phonon modes to be 11.5 and 15.3 meV, and Fröhlich coupling constants of ∼40 and 60 meV for the lead iodide and bromide perovskites, respectively. Our findings correlate well with first-principles calculations based on many-body perturbation theory, which underlines the suitability of an electronic band-structure picture for describing charge carriers in hybrid perovskites.

  14. High performance carbon nanotube--polymer nanofiber hybrid fabrics.

    Science.gov (United States)

    Yildiz, Ozkan; Stano, Kelly; Faraji, Shaghayegh; Stone, Corinne; Willis, Colin; Zhang, Xiangwu; Jur, Jesse S; Bradford, Philip D

    2015-10-28

    Stable nanoscale hybrid fabrics containing both polymer nanofibers and separate and distinct carbon nanotubes (CNTs) are highly desirable but very challenging to produce. Here, we report the first instance of such a hybrid fabric, which can be easily tailored to contain 0-100% millimeter long CNTs. The novel CNT - polymer hybrid nonwoven fabrics were created by simultaneously electrospinning nanofibers onto aligned CNT sheets which were drawn and collected on a grounded, rotating mandrel. Due to the unique properties of the CNTs, the hybrids show very high tensile strength, very small pore size, high specific surface area and electrical conductivity. In order to further examine the hybrid fabric properties, they were consolidated under pressure, and also calendered at 70 °C. After calendering, the fabric's strength increased by an order of magnitude due to increased interactions and intermingling with the CNTs. The hybrids are highly efficient as aerosol filters; consolidated hybrid fabrics with a thickness of 20 microns and areal density of only 8 g m(-2) exhibited ultra low particulate (ULPA) filter performance. The flexibility of this nanofabrication method allows for the use of many different polymer systems which provides the opportunity for engineering a wide range of nanoscale hybrid materials with desired functionalities.

  15. Research Update: The electronic structure of hybrid perovskite layers and their energetic alignment in devices

    Directory of Open Access Journals (Sweden)

    Selina Olthof

    2016-09-01

    Full Text Available In recent years, the interest in hybrid organic–inorganic perovskites has increased at a rapid pace due to their tremendous success in the field of thin film solar cells. This area closely ties together fundamental solid state research and device application, as it is necessary to understand the basic material properties to optimize the performances and open up new areas of application. In this regard, the energy levels and their respective alignment with adjacent charge transport layers play a crucial role. Currently, we are lacking a detailed understanding about the electronic structure and are struggling to understand what influences the alignment, how it varies, or how it can be intentionally modified. This research update aims at giving an overview over recent results regarding measurements of the electronic structure of hybrid perovskites using photoelectron spectroscopy to summarize the present status.

  16. Performance analysis of switching based hybrid FSO/RF transmission

    KAUST Repository

    Usman, Muneer

    2014-09-01

    Hybrid free space optical (FSO)/ radio frequency (RF) systems have emerged as a promising solution for high data rate wireless back haul.We present and analyze a switching based transmission scheme for hybrid FSO/RF system. Specifically, either FSO or RF link will be active at a certain time instance, with FSO link enjoying a higher priority. Analytical expressions have been obtained for the outage probability, average bit error rate and ergodic capacity for the resulting system. Numerical examples are presented to compare the performance of the hybrid scheme with FSO only scenario.

  17. Enhanced performance of microbial fuel cell with a bacteria/multi-walled carbon nanotube hybrid biofilm

    Science.gov (United States)

    Zhang, Peng; Liu, Jia; Qu, Youpeng; Zhang, Jian; Zhong, Yingjuan; Feng, Yujie

    2017-09-01

    The biofilm on the anode of a microbial fuel cell (MFC) is a vital component in system, and its formation and characteristic determines the performance of the system. In this study, a bacteria/Multi-Walled Carbon Nanotube (MWCNT) hybrid biofilm is fabricated by effectively inserting the MWCNTs into the anode biofilm via an adsorption-filtration method. This hybrid biofilm has been demonstrated to be an efficient structure for improving an anode biofilm performance. Electrochemical impedance spectroscopy (EIS) results show that the hybrid biofilm takes advantage of the conductivity and structure of MWCNT to enhance the electron transfer and substrate diffusion of the biofilm. With this hybrid biofilm, the current density, power density and coulombic efficiency are increased by 46.2%, 58.8% and 84.6%, respectively, relative to naturally grown biofilm. Furthermore, the start-up time is reduced by 53.8% compared with naturally grown biofilm. The perturbation test demonstrates that this type of hybrid biofilm exhibits strong adsorption ability and enhances the biofilm's resistance to a sudden change of substrate concentration. The superior performance of the hybrid biofilm with MWCNT ;nanowire; matrix compared with naturally grown biofilm demonstrates its great potential for boosting the performance of MFCs.

  18. Comparison performance of split plug-in hybrid electric vehicle and hybrid electric vehicle using ADVISOR

    Directory of Open Access Journals (Sweden)

    Mohd Rashid Muhammad Ikram

    2017-01-01

    Full Text Available Electric vehicle suffers from relatively short range and long charging times and consequently has not become an acceptable solution to the automotive consumer. The addition of an internal combustion engine to extend the range of the electric vehicle is one method of exploiting the high efficiency and lack of emissions of the electric vehicle while retaining the range and convenient refuelling times of a conventional gasoline powered vehicle. The term that describes this type of vehicle is a hybrid electric vehicle. Many configurations of hybrid electric vehicles have been designed and implemented, namely the series, parallel and power-split configurations. This paper discusses the comparison between Split Plug-in Hybrid Electric Vehicle(SPHEV and Hybrid Electric Vehicle(HEV. Modelling methods such as physics-based Resistive Companion Form technique and Bond Graph method are presented with powertrain component and system modelling examples. The modelling and simulation capability of existing tools such as ADvanced VehIcle SimulatOR (ADVISOR is demonstrated through application examples. Since power electronics is indispensable in hybrid vehicles, the issue of numerical oscillations in dynamic simulations involving power electronics is briefly addressed.

  19. The hybrid performance of the Pierre Auger Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Mostafa, Miguel, A.; /New Mexico U.

    2005-08-01

    The Pierre Auger Observatory detects ultra-high energy cosmic rays by implementing two complementary air-shower techniques. The combination of a large ground array and fluorescence detectors, known as the hybrid concept, means that a rich variety of measurements can be made on a single shower, providing much improved information over what is possible with either detector alone. In this paper the hybrid reconstruction approach and its performance are described.

  20. Electronic Commerce: A National Performance Review Initiative.

    Science.gov (United States)

    1995-09-01

    Copy 33 of 38 copies i f i I 1 3 IDA DOCUMENT D-1729 ELECTRONIC COMMERCE : A NATIONAL PERFORMANCE REVIEW INITIATIVE ID^I ^ BIPs...as reflecting the official position of any Government Agency. IDA DOCUMENT D-1729 ELECTRONIC COMMERCE : A NATIONAL PERFORMANCE REVIEW INITIATIVE...implementation of electronic commerce , as part of the Nil, so that IDA will be well prepared to support the work of the Defense Information Systems Agency

  1. Information Architecture and Electronic Market Performance

    NARCIS (Netherlands)

    O.R. Koppius (Otto)

    2002-01-01

    textabstractElectronic markets are one of the most prominent business applications of the Internet, so determining the factors that drive their performance is of great value. This thesis shows that an important driver of electronic market performance is the information architecture of the market, wh

  2. Vehicle height and posture control of the electronic air suspension system using the hybrid system approach

    Science.gov (United States)

    Sun, Xiaoqiang; Cai, Yingfeng; Chen, Long; Liu, Yanling; Wang, Shaohua

    2016-03-01

    The electronic air suspension (EAS) system can improve ride comfort, fuel economy and handling safety of vehicles by adjusting vehicle height. This paper describes the development of a novel controller using the hybrid system approach to adjust the vehicle height (height control) and to regulate the roll and pitch angles of the vehicle body during the height adjustment process (posture control). The vehicle height adjustment system of EAS poses challenging hybrid control problems, since it features different discrete modes of operation, where each mode has an associated linear continuous-time dynamic. In this paper, we propose a novel approach to the modelling and controller design problem for the vehicle height adjustment system of EAS. The system model is described firstly in the hybrid system description language (HYSDEL) to obtain a mixed logical dynamical (MLD) hybrid model. For the resulting model, a hybrid model predictive controller is tuned to improve the vehicle height and posture tracking accuracy and to achieve the on-off statuses direct control of solenoid valves. The effectiveness and performance of the proposed approach are demonstrated by simulations and actual vehicle tests.

  3. Electrochromic performance of hybrid tungsten oxide films with multiwalled-CNT additions

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chung-Kwei, E-mail: cklin@fcu.edu.tw [Department of Materials Science and Engineering, Feng Chia University, Taichung, Taiwan (China); Tseng, Sheng-Chung; Cheng, Chin-Hua; Chen, Chin-Yi [Department of Materials Science and Engineering, Feng Chia University, Taichung, Taiwan (China); Chen, Chien-Chon [Department of Energy and Resources, National United University, Miaoli, Taiwan (China)

    2011-12-30

    In this study, tungsten oxide films were prepared by sol-gel technique. Various amounts of multiwalled carbon nanotubes (MWCNTs) were added during sol-gel process to obtain hybrid WO{sub 3}/MWCNT films. The original and hybrid films were characterized by thermogravimetric analysis, X-ray diffraction analysis, and scanning electron microscopy analysis, whereas the electrochromic performance was evaluated by measuring changes in the optical transmittance caused by potentiostatic charge-discharge intercalation. The influence on the structure and properties of tungsten oxide film due to MWCNT addition was also investigated. The results showed that all of the films were amorphous and exhibited porous microstructure. The electrochromic performance of pristine WO{sub 3} film was improved by adding MWCNTs that served as a template for the growth of WO{sub 3} and resulted in more porous microstructure. The hybrid tungsten oxide films with 0.1 wt.% MWCNT addition exhibited the best electrochromic performance.

  4. Universal logic gates via liquid-electronic hybrid divider

    KAUST Repository

    Zhou, Bingpu

    2012-01-01

    We demonstrated two-input microdroplet-based universal logic gates using a liquid-electronic hybrid divider. All 16 Boolean logic functions have been realized by manipulating the applied voltages. The novel platform consists of a microfluidic chip with integrated microdroplet detectors and external electronic components. The microdroplet detectors act as the communication media for fluidic and electronic information exchange. The presence or absence of microdroplets at the detector translates into the binary signal 1 or 0. The embedded micro-mechanical pneumatically actuated valve (PAV), fabricated using the well-developed multilayer soft lithography technique, offers biocompatibility, flexibility and accuracy for the on-chip realization of different logic functions. The microfluidic chip can be scaled up to construct large-scale microfluidic logic computation. On the other hand, the microfluidic chip with a specific logic function can be applied to droplet-based chemical reactions for on-demand bio or chemical analysis. Our experimental results have presented an autonomously driven, precision-controlled microfluidic chip for chemical reactions based on the IF logic function. © 2012 The Royal Society of Chemistry.

  5. Investigation of the hybrid electron linac with negative group velocity

    Science.gov (United States)

    Savin, E. A.; Alekhanov, R. Yu.; Bulanov, A. V.; Kaminskiy, V. I.; Matsievskiy, S. V.; Sobenin, N. P.

    2016-09-01

    Hybrid accelerator, incorporating travelling wave (TW) and standing wave (SW) structures is proposed and discussed. Accelerator can sum up an RF focusing in the SW buncher and lower losses in the TW accelerating structure walls. Moreover, the structure without dumping load is proposed. Input power and beam loading are chosen to minimize power reflection from buncher maintain travelling wave regime in the accelerating structure while beam loading is on. In this case SW buncher operates as a dumping load, so all input power either goes to beam or dissipates in the wall losses, it increases structure efficiency. RF characteristics and beam dynamics simulations have been performed.

  6. Improved performance of students instructed in a hybrid PBL format.

    Science.gov (United States)

    Lian, Jiqin; He, Fengtian

    2013-01-01

    As a result of enrollment expansion, increasing numbers of students are entering into medical school in China. This combined with a shortage of teachers, means that the learning environment typically consists of a large classroom setting with traditional lecture-based learning (LBL) as the major mode to teaching and learning. In this article, we investigate the preferences for hybrid problem-based learning (hybrid-PBL) or LBL in a large classroom setting. Two hundred five second-year undergraduate students in Third Military Medical University were randomly divided to two groups. The hybrid-PBL group contained 101 students and was taught by hybrid LBL (60%) and tutor-less PBL(40%) in a large classroom. The LBL group consisted of 104 students and was taught by LBL in a large classroom too. Post-teaching performance was assessed by multiple choice questions, short-essay questions, and case-analysis questions, while the students' teaching preferences and satisfaction were assessed by questionnaires. Analysis of the results of both groups in the examination of biochemistry revealed significantly higher scores on short-essay questions and case-analysis questions in the hybrid-PBL group. Students considered hybrid-PBL to be an effective learning method and favored it over the lecture format. Furthermore, students reported positive effects of hybrid-PBL in terms of additional learning resources, critical thinking, and fun learning experiences. These results suggest that hybrid-PBL is better than the traditional LBL method at improving students' basic knowledge and problem-solving skills. Students preferred hybrid-PBL and were satisfied with it. The tutor-less PBL pattern in a large classroom setting may be feasible in Chinese medical schools. Copyright © 2012 International Union of Biochemistry and Molecular Biology, Inc.

  7. Performance evaluation of stand alone hybrid PV-wind generator

    Science.gov (United States)

    Nasir, M. N. M.; Saharuddin, N. Z.; Sulaima, M. F.; Jali, Mohd Hafiz; Bukhari, W. M.; Bohari, Z. H.; Yahaya, M. S.

    2015-05-01

    This paper presents the performance evaluation of standalone hybrid system on Photovoltaic (PV)-Wind generator at Faculty of Electrical Engineering (FKE), UTeM. The hybrid PV-Wind in UTeM system is combining wind turbine system with the solar system and the energy capacity of this hybrid system can generate up to charge the battery and supply the LED street lighting load. The purpose of this project is to evaluate the performance of PV-Wind hybrid generator. Solar radiation meter has been used to measure the solar radiation and anemometer has been used to measure the wind speed. The effectiveness of the PV-Wind system is based on the various data that has been collected and compared between them. The result shows that hybrid system has greater reliability. Based on the solar result, the correlation coefficient shows strong relationship between the two variables of radiation and current. The reading output current followed by fluctuate of solar radiation. However, the correlation coefficient is shows moderate relationship between the two variables of wind speed and voltage. Hence, the wind turbine system in FKE show does not operate consistently to produce energy source for this hybrid system compare to PV system. When the wind system does not fully operate due to inconsistent energy source, the other system which is PV will operate and supply the load for equilibrate the extra load demand.

  8. Performance evaluation of stand alone hybrid PV-wind generator

    Energy Technology Data Exchange (ETDEWEB)

    Nasir, M. N. M.; Saharuddin, N. Z.; Sulaima, M. F.; Jali, Mohd Hafiz; Bukhari, W. M.; Bohari, Z. H. [Faculty of Electrical Engineering, Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya, 76100 Melaka (Malaysia); Yahaya, M. S. [Faculty of Engineering Technology, Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya, 76100 Melaka (Malaysia)

    2015-05-15

    This paper presents the performance evaluation of standalone hybrid system on Photovoltaic (PV)-Wind generator at Faculty of Electrical Engineering (FKE), UTeM. The hybrid PV-Wind in UTeM system is combining wind turbine system with the solar system and the energy capacity of this hybrid system can generate up to charge the battery and supply the LED street lighting load. The purpose of this project is to evaluate the performance of PV-Wind hybrid generator. Solar radiation meter has been used to measure the solar radiation and anemometer has been used to measure the wind speed. The effectiveness of the PV-Wind system is based on the various data that has been collected and compared between them. The result shows that hybrid system has greater reliability. Based on the solar result, the correlation coefficient shows strong relationship between the two variables of radiation and current. The reading output current followed by fluctuate of solar radiation. However, the correlation coefficient is shows moderate relationship between the two variables of wind speed and voltage. Hence, the wind turbine system in FKE show does not operate consistently to produce energy source for this hybrid system compare to PV system. When the wind system does not fully operate due to inconsistent energy source, the other system which is PV will operate and supply the load for equilibrate the extra load demand.

  9. Domain-dependent electronic structure and optical absorption property in hybrid organic-inorganic perovskite.

    Science.gov (United States)

    Meng, Xiang; Zhang, Ruifeng; Fu, Zhongheng; Zhang, Qianfan

    2016-10-05

    Hybrid organic-inorganic perovskites, represented by materials in the CH3NH3PbI3 series, have become one of the most promising materials for solar cells with a high power conversion efficiency and low cost. The ordered Pb-I cage in such hybrid perovskites can induce the polarized cations to form a variety of polarization domains with long-range order, which will lead to the formation of specific atomic conformations or metastable crystalline phases, unique electronic band structures and optical absorption properties. Such domain-dependent characteristics play a critical role in the phase transition and service stability of such solar cells, and also open up the opportunity of tuning their electronic structure. In the present study, we systematically investigate the band structures and optical absorption properties of different electronically ordered domains in CH3NH3PbI3. By comparing different perovskites containing various cations, we have clarified the important influence of cation polarization on domain-dependent properties. Our results provide not only a possible pathway for the manipulation of band structure by applying an external field, but also a novel scheme for improving the performance and stability of hybrid perovskites.

  10. One-chip electronic detection of DNA hybridization using precision impedance-based CMOS array sensor.

    Science.gov (United States)

    Lee, Kang-Ho; Lee, Jeong-Oen; Sohn, Mi-Jin; Lee, Byunghun; Choi, Suk-Hwan; Kim, Sang Kyu; Yoon, Jun-Bo; Cho, Gyu-Hyeong

    2010-12-15

    This paper describes a label-free and fully electronic detection method of DNA hybridization, which is achieved through the use of a 16×8 microarray sensor in conjunction with a new type of impedance spectroscopy constructed with standard complementary metal-oxide-semiconductor (CMOS) technology. The impedance-based method is based on changes in the reactive capacitance and the charge-transfer resistance after hybridization with complementary DNA targets. In previously published label-free techniques, the measured capacitance presented unstable capacitive properties due to the parallel resistance that is not infinite and can cause a leakage by discharging the charge on the capacitor. This paper presents an impedance extraction method that uses excitation by triangular wave voltage, which enables a reliable measurement of both C and R producing a highly sensitive sensor with a stable operation independent of external variables. The system was fabricated in an industrial 0.35-μm 4-metal 2-poly CMOS process, integrating working electrodes and readout electronics into one chip. The integrated readout, which uses a parasitic insensitive integrator, achieves an enlarged detection range and improved noise performance. The maximum average relative variations of C and R are 31.5% and 68.6%, respectively, after hybridization with a 1 μM target DNA. The proposed sensor allows quantitative evaluation of the molecule densities on the chip with distinguishable variation in the impedance. This fully electronic microsystem has great potential for use with bioanalytical tools and point-of-care diagnosis.

  11. Pure versus hybrid: performance implications of Porter's generic strategies.

    Science.gov (United States)

    Kumar, K; Subramanian, R; Yauger, C

    1997-01-01

    This article identifies the strategic types in the hospital industry based on the hospital's use of Porter's generic strategies in their pure and hybrid forms. The article also examines differences in performance of hospitals across strategic types. Results indicate that hospitals that follow a focussed cost leadership strategy, in general, have superior performance on a variety of performance measures, while hospitals that use a combination of cost leadership and differentiation perform the poorest. Implications of findings for hospital administrators are also discussed.

  12. TiS2-MWCNT hybrid as high performance anode in lithium-ion battery

    Science.gov (United States)

    Kartick, B.; Srivastava, Suneel Kumar; Mahanty, Sourindra

    2013-09-01

    The present work reports the preparation of hybrids by simple dry grinding of titanium sulfide (TiS2) and multi-walled carbon nanotubes (MWCNTs) in different weight ratio and their characterization. X-ray diffraction and Raman studies indicated the presence of interaction between the TiS2 and MWCNT. Field emission scanning electron microscopy and high resolution transmission electron microscopy showed the formation of three-dimensional architecture and co-dispersion in TiS2-MWCNT (1:1) hybrid. X-ray photoelectron spectroscopy also confirmed the presence of TiS2 and MWCNT in the prepared hybrid. Thermogravimetric analysis indicated an increase in thermal stability with higher MWCNT content. The results of the electrochemical analyses indicated that TiS2-MWCNT (1:1) hybrid exhibited an enhanced performance as lithium-ion battery anode. The initial specific capacity was found to be ≈450 mAh g-1 with 80 % retention in capacity after 50 discharge-charge cycles. These values are significantly higher compared to those for TiS2, MWCNT or other TiS2-MWCNT hybrids. Such improved performance is attributed to the presence of a synergistic effect between TiS2 and MWCNT.

  13. High Performance Electrolyzers for Hybrid Thermochemical Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Dr. John W. Weidner

    2009-05-10

    Extensive electrolyzer testing was performed at the University of South Carolina (USC). Emphasis was given to understanding water transport under various operating (i.e., temperature, membrane pressure differential and current density) and design (i.e., membrane thickness) conditions when it became apparent that water transport plays a deciding role in cell voltage. A mathematical model was developed to further understand the mechanisms of water and SO2 transport, and to predict the effect of operating and design parameters on electrolyzer performance.

  14. Optics of high-performance electron microscopes*

    OpenAIRE

    H H Rose

    2016-01-01

    During recent years, the theory of charged particle optics together with advances in fabrication tolerances and experimental techniques has lead to very significant advances in high-performance electron microscopes. Here, we will describe which theoretical tools, inventions and designs have driven this development. We cover the basic theory of higher-order electron optics and of image formation in electron microscopes. This leads to a description of different methods to correct aberrations by...

  15. Performance Training Carrel for Electronics Principles Course.

    Science.gov (United States)

    Kargo, Donald W.; Steffen, Dale A.

    This manual provides documentation for the design, construction, and operation of an interactive electronics training panel developed for a computer assisted performance training carrel. The panel is a plug-in module designed to simulate electronic circuitry and a PMS-6 multimeter as required for a troubleshooting fundamentals lesson in an Air…

  16. Electronics Technology. Performance Objectives. Basic Course.

    Science.gov (United States)

    Campbell, Guy

    Several intermediate performance objectives and corresponding criterion measures are listed for each of 20 terminal objectives for a basic electronics technology course. The materials were developed for a two-semester course (2 hours daily) designed to include instruction in basic electricity and electronic fundamentals, and to develop skills and…

  17. Reduced density matrix hybrid approach: application to electronic energy transfer.

    Science.gov (United States)

    Berkelbach, Timothy C; Markland, Thomas E; Reichman, David R

    2012-02-28

    Electronic energy transfer in the condensed phase, such as that occurring in photosynthetic complexes, frequently occurs in regimes where the energy scales of the system and environment are similar. This situation provides a challenge to theoretical investigation since most approaches are accurate only when a certain energetic parameter is small compared to others in the problem. Here we show that in these difficult regimes, the Ehrenfest approach provides a good starting point for a dynamical description of the energy transfer process due to its ability to accurately treat coupling to slow environmental modes. To further improve on the accuracy of the Ehrenfest approach, we use our reduced density matrix hybrid framework to treat the faster environmental modes quantum mechanically, at the level of a perturbative master equation. This combined approach is shown to provide an efficient and quantitative description of electronic energy transfer in a model dimer and the Fenna-Matthews-Olson complex and is used to investigate the effect of environmental preparation on the resulting dynamics.

  18. 3D electronics for hybrid pixel detectors – TWEPP-09

    CERN Document Server

    Godiot, S; Chantepie, B; Clémens, J C; Fei, R; Fleury, J; Fougeron, D; Garcia-Sciveres, M; Hemperek, T; Karagounis, M; Krueger, H; Mekkaoui, A; Pangaud, P; Rozanov, A; Wermes, N

    2009-01-01

    Future hybrid pixel detectors are asking for smaller pixels in order to improve spatial resolution and to deal with an increasing counting rate. Facing these requirements is foreseen to be done by microelectronics technology shrinking. However, this straightforward approach presents some disadvantages in term of performances and cost. New 3D technologies offer an alternative way with the advantage of technology mixing. For the upgrade of ATLAS pixel detector, a 3D conception of the read-out chip appeared as an interesting solution. Splitting the pixel functionalities into two separate levels will reduce pixel size and open the opportunity to take benefit of technology's mixing. Based on a previous prototype of the read-out chip FE-I4 (IBM 130nm), this paper presents the design of a hybrid pixel read-out chip using threedimensional Tezzaron-Chartered technology. In order to disentangle effects due to Chartered 130nm technology from effects involved by 3D architecture, a first translation of FEI4 prototype had ...

  19. High performance radiation curable hybrid coatings

    Science.gov (United States)

    Nik Salleh, Nik Ghazali; Sofian Alias, Mohd; Gläsel, H.-J.; Mehnert, R.

    2013-03-01

    Radiation curing is one of the most effective processes to produce rapidly composite materials at ambient temperature. Silica nanoparticles can be introduced into radiation curable resins to produce scratch and abrasion resistant materials, which can be used as sealants or clear coatings. In preparation of radiation cured polymeric composites for wood based products such as medium density fiberboard etc., we synthesized radiation curable silico-organic nanoparticles from silica/acrylates system. These nano-sized silica particles were used as fillers. Epoxy acrylates was used as prepolymer while pentaerythritol triacrylate and tetraacrylate (PETIA) was used as monomer. The acrylated epoxy resin synthesized from palm oil based product (EPOLA) i.e. bio-renewable raw materials was also used in the system. The surface of the silica was chemically modified to improve the embedding of the filler within the acrylate matrix. Modification of the silica surface using silane was done to overcome the problem of incompatibility with acrylates at high silica contents. The nature of the nanoparticles is now changed from hydrophilic to organophilic. In these investigations, we use low energy electron beam accelerator to initiate polymerization and interaction at the interface between the nanoparticles and the monomeric materials. These polymerization active nanoparticles were obtained by heterogeneous hydrolytic condensation of the silane to the silanol groups of the silica particles. Formulations useful for technical coating processes could be prepared and these composite materials showed highly improved mechanical properties. They also provided a high network density whilst the coatings remain transparent. These polymeric nanocomposites show excellent resistances toward abrasion properties including scratch property as compared to pure acrylates.

  20. Three-year randomised clinical trial to evaluate the clinical performance, quantitative and qualitative wear patterns of hybrid composite restorations.

    Science.gov (United States)

    Palaniappan, Senthamaraiselvi; Elsen, Liesbeth; Lijnen, Inge; Peumans, Marleen; Van Meerbeek, Bart; Lambrechts, Paul

    2010-08-01

    The aim of the study was to compare the clinical performance, quantitative and qualitative wear patterns of conventional hybrid (Tetric Ceram), micro-filled hybrid (Gradia Direct Posterior) and nano-hybrid (Tetric EvoCeram, TEC) posterior composite restorations in a 3-year randomised clinical trial. Sixteen Tetric Ceram, 17 TEC and 16 Gradia Direct Posterior restorations were placed in human molars and evaluated at baseline, 6, 12, 24 and 36 months of clinical service according to US Public Health Service criteria. The gypsum replicas at each recall were used for 3D laser scanning to quantify wear, and the epoxy resin replicas were observed under scanning electron microscope to study the qualitative wear patterns. After 3 years of clinical service, the three hybrid restorative materials performed clinically well in posterior cavities. Within the observation period, the nano-hybrid and micro-hybrid restorations evolved better in polishability with improved surface gloss retention than the conventional hybrid counterpart. The three hybrid composites showed enamel-like vertical wear and cavity-size dependant volume loss magnitude. Qualitatively, while the micro-filled and nano-hybrid composite restorations exhibited signs of fatigue similar to the conventional hybrid composite restorations at heavy occlusal contact area, their light occlusal contact areas showed less surface pitting after 3 years of clinical service.

  1. High-performance perovskite-graphene hybrid photodetector.

    Science.gov (United States)

    Lee, Youngbin; Kwon, Jeong; Hwang, Euyheon; Ra, Chang-Ho; Yoo, Won Jong; Ahn, Jong-Hyun; Park, Jong Hyeok; Cho, Jeong Ho

    2015-01-01

    A high-performance novel photodetector is demonstrated, which consists of graphene and CH3 NH3 PbI3 perovskite layers. The resulting hybrid photodetector exhibits a dramatically enhanced photo responsivity (180 A/W) and effective quantum efficiency (5× 10(4) %) over a broad bandwidth within the UV and visible ranges.

  2. Performance Assessment of Hybrid Data Fusion and Tracking Algorithms

    DEFF Research Database (Denmark)

    Sand, Stephan; Mensing, Christian; Laaraiedh, Mohamed

    2009-01-01

    This paper presents an overview on the performance of hybrid data fusion and tracking algorithms evaluated in the WHERE consortium. The focus is on three scenarios. For the small scale indoor scenario with ultra wideband (UWB) complementing cellular communication systems, the accuracy can vary in...

  3. Combining Performance and Flexibility for RMS with a Hybrid Architecture

    NARCIS (Netherlands)

    Arjan van Zanten; Dick van der Steen; Dennis Koole; Ing. Erik Puik; Patrick Wit; Pascal Muller; Leo van Moergestel; Arjan Groenewegen; John-Jules Meyer; Daniël Telgen

    2013-01-01

    Author supplied Combining Performance and Flexibility for RMS with a Hybrid Architecture Dani¨el Telgen 12? , Leo van Moergestel 1 , Erik Puik 1 , Pascal Muller 1 , Arjan Groenewegen 1 , Dick van der Steen 1 , Dennis Koole 1 , Patrick de Wit 1 , Arjen van Zanten 1 , and John-Jules

  4. Combining Performance and Flexibility for RMS with a Hybrid Architecture

    NARCIS (Netherlands)

    Telgen, Daniël; Moergestel, Leo van; Puik, Erik; Muller, Pascal; Groenewegen, Arjan; Steen, Dick van der; Koole, Dennis; Wit, Patrick; Zanten, Arjan van; Meyer, John-Jules

    2013-01-01

    Author supplied Combining Performance and Flexibility for RMS with a Hybrid Architecture Dani¨el Telgen 12? , Leo van Moergestel 1 , Erik Puik 1 , Pascal Muller 1 , Arjan Groenewegen 1 , Dick van der Steen 1 , Dennis Koole 1 , Patrick de Wit 1 , Arjen van Zanten 1 , and John-Jules Meyer 2 1 Departm

  5. Game Performance and Understanding within a Hybrid Sport Education Season

    Science.gov (United States)

    Farias, Cláudio Filipe; Mesquita, Isabel Ribeiro; Hastie, Peter A.

    2015-01-01

    The impact of a hybrid Sport Education-Invasion Games Competence Model (IGCM) unit of instruction on students' game performance and game understanding in soccer was examined in this study. Pre- and posttest measures were collected from one fifth grade class of students (n = 24, mean age 10.3) residing in Portugal during a 17-lesson unit of…

  6. Improved performance of silicon nanowire/cadmium telluride quantum dots/organic hybrid solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Zhaoyun [National Laboratory of Solid State Microstructures and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Jiangsu University of Science and Technology, Zhenjiang 212003, Jiangsu Province (China); Xu, Ling, E-mail: xuling@nju.edu.cn [National Laboratory of Solid State Microstructures and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Zhang, Renqi; Xue, Zhaoguo; Wang, Hongyu; Xu, Jun; Yu, Yao; Su, Weining; Ma, Zhongyuan; Chen, Kunji [National Laboratory of Solid State Microstructures and School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China)

    2015-04-15

    Highlights: • We introduce an intermediate cadmium telluride quantum dots (CdTe QDs) layer between the organic with silicon nanowires of hybrid solar cells as a down-shifting layer. • The hybrid solar cell got the maximum short circuit current density of 33.5 mA/cm{sup 2}, getting an increase of 15.1% comparing to solar cell without CdTe QDs. • The PCE of the hybrid solar cells with CdTe QDs layer increases 28.8%. - Abstract: We fabricated silicon nanowire/cadmium telluride quantum dots (CdTe QDs)/organic hybrid solar cells and investigated their structure and electrical properties. Transmission electron microscope revealed that CdTe QDs were uniformly distributed on the surface of the silicon nanowires, which made PEDOT:PSS easily filled the space between SiNWs. The current density–voltage (J–V) characteristics of hybrid solar cells were investigated both in dark and under illumination. The result shows that the performance of the hybrid solar cells with CdTe QDs layer has an obvious improvement. The optimal short-circuit current density (J{sub sc}) of solar cells with CdTe QDs layer can reach 33.5 mA/cm{sup 2}. Compared with the solar cells without CdTe QDs, J{sub sc} has an increase of 15.1%. Power conversion efficiency of solar cells also increases by 28.8%. The enhanced performance of the hybrid solar cells with CdTe QDs layers are ascribed to down-shifting effect of CdTe QDs and the modification of the silicon nanowires surface with CdTe QDs. The result of our experiments suggests that hybrid solar cells with CdTe QDs modified are promising candidates for solar cell application.

  7. FHSS DSSS And Hybrid DSFH Performance Evaluation For VSAT

    Directory of Open Access Journals (Sweden)

    Lina E. Alatabani

    2015-08-01

    Full Text Available Abstract The performance of any radio communication system is affected by several factors such as interference and jamming caused by some other parallel networks for the purpose of decreasing the performance of a given system. Direct Sequence Spread Spectrum DSSS Frequency Hopping Spread Spectrum FHSS and a hybrid approach of both techniques DSFH are proposed to solve the problem. Whereas DSSS generates a sequence of bit and sends them over a fixed data rate and spread the spectrum with a spreading sequence FHSS send the data into different channels with variable data rates and the hybrid DSFH approach takes advantage of DSSS and uses it in multiple channels. Various modulation techniques which are suitable for Very small aperture terminal VSAT were simulated with each of the mentioned approaches such as Phase Ship Keying PSK Frequency Shift Keying FSK and Quadrature Amplitude Modulation QAM to in order to work properly with each technique. The performance of each approach was evaluated in terms of Signal to Noise Ratio vs Bit Error Rate throughput delay and datarate. The results are very close to each other in terms of BER but the best approach was the DSSS. The Hybrid DSFH needs more power to operate so it best fits the applications with high frequencies. The Hybrid DSFH approach was the best of the three tested approaches in terms of throughput delay and datarate. The FHSS technique was average in all the parameters and had greater delay time due to the delay gap in the hopping process.

  8. Lower hybrid current drive favoured by electron cyclotron radiofrequency heating

    Energy Technology Data Exchange (ETDEWEB)

    Cesario, R.; Cardinali, A.; Castaldo, C.; Marinucci, M.; Tuccillo, A. A. [Associazione EURATOM/ENEA sulla Fusione, Centro Ricerche Frascati, 00044, Frascati (Italy); Amicucci, L.; Galli, A. [Università di Roma Sapienza, Dipartimento Ingegneria Elettronica, Rome (Italy); Giruzzi, G. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Napoli, F.; Schettini, G. [Università di Roma Tre, Dipartimento Ingegneria Elettronica, Rome (Italy)

    2014-02-12

    The important goal of adding to the bootstrap a fraction of non-inductive plasma current, which would be controlled for obtaining and optimizing steady-state profiles, can be reached by using the Current Drive produced by Lower Hybrid waves (LHCD). FTU (Frascati Tokamak Upgrade) experiments demonstrated, indeed, that LHCD is effective at reactor-graded high plasma density, and the LH spectral broadening is reduced, operating with higher electron temperature in the outer region of plasma column (T{sub e-periphery}). This method was obtained following the guidelines of theoretical predictions indicating that the broadening of launched spectrum produced by parametric instability (PI) should be reduced, and the LHCD effect at high density consequently enabled, under higher (T{sub e-periphery}). In FTU, the temperature increase in the outer plasma region was obtained by operating with reduced particle recycling, lithized walls and deep gas fuelling by means of fast pellet. Heating plasma periphery with electron cyclotron resonant waves (ECRH) will provide a further tool for achieving steady-state operations. New FTU experimental results are presented here, demonstrating that temperature effect at the plasma periphery, affecting LH penetration, occurs in a range of plasma parameters broader than in previous work. New information is also shown on the modelling assessing frequencies and growth rates of the PI coupled modes responsible of spectral broadening. Finally, we present the design of an experiment scheduled on FTU next campaign, where ECRH power is used to slightly increase the electron temperature in the outer plasma region of a high-density discharge aiming at restoring LHCD. Consequent to model results, by operating with a toroidal magnetic field of 6.3 T, useful for locating the electron cyclotron resonant layer at the periphery of the plasma column (r/a∼0.8, f{sub 0}=144 GHz), an increase of T{sub e} in the outer plasma (from 40 eV to 80 eV at r/a∼0.8) is

  9. Hybrid additive manufacturing of 3D electronic systems

    Science.gov (United States)

    Li, J.; Wasley, T.; Nguyen, T. T.; Ta, V. D.; Shephard, J. D.; Stringer, J.; Smith, P.; Esenturk, E.; Connaughton, C.; Kay, R.

    2016-10-01

    A novel hybrid additive manufacturing (AM) technology combining digital light projection (DLP) stereolithography (SL) with 3D micro-dispensing alongside conventional surface mount packaging is presented in this work. This technology overcomes the inherent limitations of individual AM processes and integrates seamlessly with conventional packaging processes to enable the deposition of multiple materials. This facilitates the creation of bespoke end-use products with complex 3D geometry and multi-layer embedded electronic systems. Through a combination of four-point probe measurement and non-contact focus variation microscopy, it was identified that there was no obvious adverse effect of DLP SL embedding process on the electrical conductivity of printed conductors. The resistivity maintained to be less than 4  ×  10-4 Ω · cm before and after DLP SL embedding when cured at 100 °C for 1 h. The mechanical strength of SL specimens with thick polymerized layers was also identified through tensile testing. It was found that the polymerization thickness should be minimised (less than 2 mm) to maximise the bonding strength. As a demonstrator a polymer pyramid with embedded triple-layer 555 LED blinking circuitry was successfully fabricated to prove the technical viability.

  10. Stability of hybrid modes of a single-component electron plasma containing an admixture of background gas ions

    Science.gov (United States)

    Yeliseyev, Yu. N.

    2014-05-01

    The spectrum of eigenmodes of a waveguide completely filled with a cold electron plasma containing a small admixture of ions produced due to electron-impact ionization of background gas atoms is calculated numerically. The calculations were performed within the entire range of allowable values of the radial electric and longitudinal magnetic fields for both magnetized and unmagnetized ions by using the earlier derived nonlocal dispersion relation [Plasma Phys. Rep. 36, 563 (2010)]. The spectrum consists of three families of electron modes with frequencies equal to the Doppler-shifted upper and lower hybrid frequencies and modified ion cyclotron (MIC) modes. When the Doppler shift caused by electron rotation in the crossed electric and magnetic fields compensates for the hybrid frequency, the electron modes become low-frequency modes and interact with the ion modes. For m = 1, only the lower hybrid modes can be low-frequency ones, whereas at m ≥ 2, both lower and upper hybrid modes can be low-frequency ones. The spectrum of modes having the azimuthal number m = 2 is thoroughly analyzed. It is shown that, in this case, the lower hybrid modes behave similar to the m = 1 modes. The dispersion curves of the upper hybrid modes intersect with all harmonics of the MIC frequency (positive, negative, and zero) and are unstable in the vicinities of the intersections. The maximum value of the instability growth rate is several times higher than the ion plasma frequency. The MIC modes are unstable within a wide range of the field strengths, and their growth rates are two orders of magnitude slower. Instabilities are caused by the relative motion of electrons and ions (the transverse current) and the anisotropy of the ion distribution function.

  11. One- and many-electron self-interaction error in local and global hybrid functionals

    Science.gov (United States)

    Schmidt, Tobias; Kümmel, Stephan

    2016-04-01

    Electronic self-interaction poses a fundamental challenge in density-functional theory. It greatly limits, e.g., the physical interpretation of eigenvalues as electron removal energies. We here investigate whether local hybrid functionals that are designed to be free from one-electron self-interaction lead to occupied Kohn-Sham eigenvalues and orbitals that approximate photoemission observables well. We compare the local hybrid results to the ones from global hybrid functionals that only partially counteract the self-interaction, and to the results that are obtained with a Perdew-Zunger-type self-interaction correction. Furthermore, we check whether being nominally free from one-electron self-interaction translates into a reduced many-electron self-interaction error. Our findings show that this is not the case for the local hybrid functionals that we studied: In practice they are similar to global hybrids in many respects, despite being formally superior. This finding indicates that there is a conceptual difference between the Perdew-Zunger way and the local hybrid way of translating the one-electron condition to a many-electron system. We also point out and solve some difficulties that occur when using local hybrid functionals in combination with pseudopotentials.

  12. High performance flexible electronics for biomedical devices.

    Science.gov (United States)

    Salvatore, Giovanni A; Munzenrieder, Niko; Zysset, Christoph; Kinkeldei, Thomas; Petti, Luisa; Troster, Gerhard

    2014-01-01

    Plastic electronics is soft, deformable and lightweight and it is suitable for the realization of devices which can form an intimate interface with the body, be implanted or integrated into textile for wearable and biomedical applications. Here, we present flexible electronics based on amorphous oxide semiconductors (a-IGZO) whose performance can achieve MHz frequency even when bent around hair. We developed an assembly technique to integrate complex electronic functionalities into textile while preserving the softness of the garment. All this and further developments can open up new opportunities in health monitoring, biotechnology and telemedicine.

  13. Different proportions of C/KCu7S4 hybrid structure for high-performance supercapacitors

    Science.gov (United States)

    Dai, Shuge; Xi, Yi; Hu, Chenguo; Yue, Xule; Cheng, Lu; Wang, Guo

    2014-10-01

    KCu7S4 has the channel structure and minor resistance. Its double larger channels ensure that the ions can well exchange with other's, at the same time, can shorten the ionic diffusion path and improve the ionic and electronic transport. So KCu7S4 shows good electrochemical property. The paper reports a novel and high performance supercapacitor based on hybrid carbon particles and KCu7S4 (C/KCu7S4) electrode. For the hybrid structure with different proportions of C and KCu7S4, the C/KCu7S4 (1:10) hybrid supercapacitor shows preferable electrochemical performance and large specific capacitance (469 mF cm-2) at high charge-discharge rate (2 mA), still retaining ∼95% of the capacitance over 5000 cycles by charge-discharge process at a fixed current of 10 mA. Three supercapacitor units in series can light 50 light-emitting diodes (LEDs) for 2.5 min, 10 LEDs for 4 min, one LED for 5.5 min. The much-increased capacity, rate capability, and cycling stability may be attributed to the superionic conductive KCu7S4 nanowires and C/KCu7S4 hybrid structure, which improve ionic and electronic transport, enhance the kinetics of redox reactions through the electrode system.

  14. Study of MEH–PPV/PCBM active layer morphology and its application for hybrid solar cell performance

    Indian Academy of Sciences (India)

    Quynh Nhu Nguyen Truong; Nguyen Tam Nguyen Truong; Chinho Park; Jae Hak Jung

    2012-04-01

    Surface morphologies of MEH–PPV:PCBM active layers were optimized by investigating ITO substrate treated with oxygen and nitrogen plasma. This treatment effectively improved smoothness, transmittance, and contact angle of ITO’s, resulting in good anode contacts for hybrid device structures. The consistently improved performance of hybrid solar cells was also achieved. The surface properties of treated and untreated ITO substrates were compared by contact angle, four point probe, scanning electron microscopy, and atomic force microscopy.

  15. The performance of organic electronic ratchets

    Directory of Open Access Journals (Sweden)

    Erik M. Roeling

    2012-03-01

    Full Text Available Organic electronic ratchets rectify time-correlated external driving forces, giving output powers that can drive electronic circuitry. In this work their performance characteristics are investigated using numerical modeling and measurements. It is shown how the characteristic parameters of the time–varying asymmetric potential like length scales and amplitude, as well as the density and mobility of the charge carriers in the device influence the performance characteristics. Various ratchet efficiencies and their relations are discussed. With all settings close to optimum, a ratchet with charge displacement and power efficiencies close to 50% and 7% respectively is obtained.

  16. Performance Studies of Pixel Hybrid Photon Detectors for the LHCb RICH Counters

    CERN Document Server

    Aglieri Rinella, G; Piedigrossi, D; Van Lysebetten, A

    2004-01-01

    The Pixel Hybrid Photon Detector is a vacuum tube with a multi-alkali photo cathode, high voltage cross-focused electron optics and an anode consisting of a silicon pixel detector bump-bonded to a readout CMOS electronic chip fully encapsulated in the device. The Pixel HPD fulfils the requirements of the Ring Imaging Cherenkov counters of the LHCb experiment at LHC. The performances of the Pixel HPD will be discussed with reference to laboratory measurements, Cherenkov light imaging in recent beam tests, image distortions due to a magnetic field.

  17. Performance studies of pixel hybrid photon detectors for the LHCb RICH counters

    CERN Document Server

    Aglieri-Rinella, G; Piedigrossi, D; Van Lysebetten, A

    2006-01-01

    The Pixel Hybrid Photon Detector is a vacuum tube with a multi-alkali photo cathode, high voltage cross-focused electron optics and an anode consisting of a silicon pixel detector bump-bonded to a readout CMOS electronic chip fully encapsulated in the device. The Pixel HPD fulfils the requirements of the Ring Imaging Cherenkov counters of the LHCb experiment at LHC. The performances of the Pixel HPD will be discussed with reference to laboratory measurements, Cherenkov light imaging in recent beam tests, image distortions due to a magnetic field.

  18. Hybrid fluorescence and electron cryo-microscopy for simultaneous electron and photon imaging.

    Science.gov (United States)

    Iijima, Hirofumi; Fukuda, Yoshiyuki; Arai, Yoshihiro; Terakawa, Susumu; Yamamoto, Naoki; Nagayama, Kuniaki

    2014-01-01

    Integration of fluorescence light and transmission electron microscopy into the same device would represent an important advance in correlative microscopy, which traditionally involves two separate microscopes for imaging. To achieve such integration, the primary technical challenge that must be solved regards how to arrange two objective lenses used for light and electron microscopy in such a manner that they can properly focus on a single specimen. To address this issue, both lateral displacement of the specimen between two lenses and specimen rotation have been proposed. Such movement of the specimen allows sequential collection of two kinds of microscopic images of a single target, but prevents simultaneous imaging. This shortcoming has been made up by using a simple optical device, a reflection mirror. Here, we present an approach toward the versatile integration of fluorescence and electron microscopy for simultaneous imaging. The potential of simultaneous hybrid microscopy was demonstrated by fluorescence and electron sequential imaging of a fluorescent protein expressed in cells and cathodoluminescence imaging of fluorescent beads. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. New materials strategies for creating hybrid electronic circuitry (Presentation Video)

    Science.gov (United States)

    Marks, Tobin J.

    2013-09-01

    This lecture focuses on the challenging design and realization of new materials for creating unconventional electronic circuitry. Fabrication methodologies to achieve these goals include high-throughput, large-area printing techniques. Materials design topics to be discussed include: 1. Rationally designed high-mobility p- and n-type organic semiconductors for printed organic CMOS, 2. Polycrystalline and amorphous oxide semiconductors for transparent and mechanically flexible electronics, 3) Self-assembled and printable high-k nanodielectrics enabling ultra-large capacitance, low leakage, high breakdown fields, minimal trapped interfacial charge, and device radiation hardness. 4) Combining these materials sets to fabricate a variety of high-performance thin-film transistor-based devices.

  20. Electronic Structure Rearrangements in Hybrid Ribozyme/Protein Catalysis

    Science.gov (United States)

    Kang, Jiyoung; Kino, Hiori; Field, Martin J.; Tateno, Masaru

    2017-04-01

    We analyzed the electronic structural changes that occur in the reaction cycle of a biological catalyst composed of RNA and protein, and elucidated the dynamical rearrangements of the electronic structure that was obtained from our previous study in which ab initio quantum mechanics/molecular mechanics molecular dynamics simulations were performed. Notable results that we obtained include the generation of a reactive HOMO that is responsible for bond formation in the initial stages of the reaction, and the appearance of a reactive LUMO that is involved in the bond rupture that leads to products. We denote these changes as dynamical induction of the reactive HOMO (DIRH) and LUMO (DIRL), respectively. Interestingly, we also find that the induction of the reactive HOMO is enhanced by the formation of a low-barrier hydrogen bond (LBHB), which, to the best of our knowledge, represents a novel role for LBHBs in enzymatic systems.

  1. Polymer brush and inorganic oxide hybrid nanodielectrics for high performance organic transistors.

    Science.gov (United States)

    Li, Liqiang; Hu, Wenping; Chi, Lifeng; Fuchs, Harald

    2010-04-29

    A novel covalence-linked PMMA-SiO(2) hybrid nanodielectrics was prepared by grafting approximately 10 nm PMMA brush onto the SiO(2) (approximately 9 nm) surface, which effectively combines the respective merits of PMMA and SiO(2). As a result, the hybrid nanodielectrics exhibit excellent dielectric performance (e.g., low leakage density (<10(-7) A/cm(2) at 6 MV/cm), high breakdown voltage (7 MV/cm), high capacitance (142 nF/cm(2)), good operational stability, and good compatibility with organic semiconductors), and enable organic field-effect transistors (OFETs) to work with high performance and low voltage. These results may open a way to build ultrathin dielectrics for high performance transistor and circuit, as well as for microelectronics, nanoelectronics, and organic electronics.

  2. Optics of high-performance electron microscopes.

    Science.gov (United States)

    Rose, H H

    2008-01-01

    During recent years, the theory of charged particle optics together with advances in fabrication tolerances and experimental techniques has lead to very significant advances in high-performance electron microscopes. Here, we will describe which theoretical tools, inventions and designs have driven this development. We cover the basic theory of higher-order electron optics and of image formation in electron microscopes. This leads to a description of different methods to correct aberrations by multipole fields and to a discussion of the most advanced design that take advantage of these techniques. The theory of electron mirrors is developed and it is shown how this can be used to correct aberrations and to design energy filters. Finally, different types of energy filters are described.

  3. Project Startup: Evaluating the Performance of Hydraulic Hybrid Refuse Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    2015-09-01

    The Fleet Test and Evaluation Team at the National Renewable Energy Laboratory (NREL) is evaluating the in-service performance of 10 next-generation hydraulic hybrid refuse vehicles (HHVs), 8 previous-generation HHVs, and 8 comparable conventional diesel vehicles operated by Miami-Dade County's Public Works and Waste Management Department in southern Florida. The HHVs under study - Autocar E3 refuse trucks equipped with Parker Hannifin's RunWise Advanced Series Hybrid Drive systems - can recover as much as 70 percent of the energy typically lost during braking and reuse it to power the vehicle. NREL's evaluation will assess the performance of this technology in commercial operation and help Miami-Dade County determine the ideal routes for maximizing the fuel-saving potential of its HHVs.

  4. Performance Characteristics of Absorption Hybrid Cycle Introduced Compressor

    Science.gov (United States)

    Iyoki, Shigeki; Kotani, Yuji; Uemura, Tadashi

    In this paper, four kinds of absorption hybrid cycle which introduced the compressor in the absorption cycle were proposed. As basic cycle of absorption refrigerating machine, the following were chosen: two kinds of single-stage absorption refrigerating machine and two kinds of double effect absorption refrigerating machine. As a working medium-absorbent system, NH3-H2O system, C2H5NH2-H2O system and C2H5NH2-H2O-LiBr system were adopted. Using these three kinds of working medium-absorbent system, the performance characteristics of four kinds of absorption hybrid cycle were simulated. And the performance characteristics of these cycles were compared.

  5. Role of Microstructure in the Electron-Hole Interaction of Hybrid Lead-Halide Perovskites

    Science.gov (United States)

    Frost, Jarvist M.; Barker, Alex J.; De Bastiani, Michele; Gandini, Marina; Marras, Sergio; Lanzani, Guglielmo; Walsh, Aron; Petrozza, Annamaria

    2015-01-01

    Solar cells based on hybrid inorganic-organic halide perovskites have demonstrated high power conversion efficiencies in a range of architectures. The existence and stability of bound electron-hole pairs in these materials, and their role in the exceptional performance of optoelectronic devices, remains a controversial issue. Here we demonstrate, through a combination of optical spectroscopy and multiscale modeling as a function of the degree of polycrystallinity and temperature, that the electron-hole interaction is sensitive to the microstructure of the material. The long-range order is disrupted by polycrystalline disorder and the variations in electrostatic potential found for smaller crystals suppress exciton formation, while larger crystals of the same composition demonstrate an unambiguous excitonic state. We conclude that fabrication procedures and morphology strongly influence perovskite behaviour, with both free carrier and excitonic regimes possible, with strong implications for optoelectronic devices. PMID:26442125

  6. Hybrid bio-organic interfaces with matchable nanoscale topography for durable high extracellular electron transfer activity.

    Science.gov (United States)

    Ding, Chunmei; Liu, Huan; Lv, Meiling; Zhao, Tianyi; Zhu, Ying; Jiang, Lei

    2014-07-21

    Here, we developed a novel hybrid bio-organic interface with matchable nano-scale topography between a polypyrrole nanowire array (PPy-NA) and the bacterium Shewanella, which enabled a remarkably increased extracellular electron transfer (EET) current from genus Shewanella over a rather long period. PPy-NA thus exhibited outstanding performance in mediating bacterial EET, which was superior to normal electrodes such as carbon plates, Au and tin-doped In₂O₃. It was proposed that the combined effect of the inherent electrochemical nature of PPy and the porous structured bacterial network that was generated on the PPy-NA enabled long-term stability, while the high efficiency was attributed to the enhanced electron transfer rate between PPy-NA and microbes caused by the enhanced local topological interactions.

  7. Role of Microstructure in the Electron-Hole Interaction of Hybrid Lead-Halide Perovskites.

    Science.gov (United States)

    Grancini, Giulia; Srimath Kandada, Ajay Ram; Frost, Jarvist M; Barker, Alex J; De Bastiani, Michele; Gandini, Marina; Marras, Sergio; Lanzani, Guglielmo; Walsh, Aron; Petrozza, Annamaria

    2015-10-01

    Solar cells based on hybrid inorganic-organic halide perovskites have demonstrated high power conversion efficiencies in a range of architectures. The existence and stability of bound electron-hole pairs in these materials, and their role in the exceptional performance of optoelectronic devices, remains a controversial issue. Here we demonstrate, through a combination of optical spectroscopy and multiscale modeling as a function of the degree of polycrystallinity and temperature, that the electron-hole interaction is sensitive to the microstructure of the material. The long-range order is disrupted by polycrystalline disorder and the variations in electrostatic potential found for smaller crystals suppress exciton formation, while larger crystals of the same composition demonstrate an unambiguous excitonic state. We conclude that fabrication procedures and morphology strongly influence perovskite behaviour, with both free carrier and excitonic regimes possible, with strong implications for optoelectronic devices.

  8. Performance Analysis of a Hybrid Power Cutting System for Roadheader

    Directory of Open Access Journals (Sweden)

    Yang Yang

    2017-01-01

    Full Text Available An electrohydraulic hybrid power cutting transmission system for roadheader under specific working condition was proposed in this paper. The overall model for the new system composed of an electric motor model, a hydraulic pump-motor model, a torsional planetary set model, and a hybrid power train model was established. The working mode characteristics were simulated under the conditions of taking the effect of cutting picks into account. The advantages of new hybrid power cutting system about the dynamic response under shock load were investigated compared with the traditional cutting system. The results illustrated that the hybrid power system had an obvious cushioning in terms of the dynamic load of cutting electric motor and planetary gear set. Besides, the hydraulic motor could provide an auxiliary power to improve the performance of the electric motor. With further analysis, a dynamic load was found to have a high relation to the stiffness and damping of coupling in the transmission train. The results could be a useful guide for the design of cutting transmission of roadheader.

  9. Hybrid competitive strategies, organizational structure, and firm performance

    OpenAIRE

    Pertusa Ortega, Eva María

    2008-01-01

    Comunicación presentada en SMS 28th Annual International Conference, Cologne, Germany, October 12-15, 2008. This paper analyzes the internal characteristics of organizational structure which have an influence on the development of hybrid competitive strategies and their link to firm performance. The study examines a sample of large Spanish firms belonging to different sectors by means of the Partial Least Squares (PLS) technique, using formative dimensions for competitive strategy and orga...

  10. Run 1 Legacy Performance : electrons/photons

    CERN Document Server

    Damazio, D O; The ATLAS collaboration

    2014-01-01

    In this talk, the run 1 legacy performance of the electron and photon reconstruction and identification in the ATLAS and CMS experiments will be described, as well as the associated systematic uncertainties. The two speakers should try to enlight the differences of performances between the two experiments, and explain what worked better/worse than planned, as well as the lessons for the run 2.

  11. High Performance Electronics on Flexible Silicon

    KAUST Repository

    Sevilla, Galo T.

    2016-09-01

    Over the last few years, flexible electronic systems have gained increased attention from researchers around the world because of their potential to create new applications such as flexible displays, flexible energy harvesters, artificial skin, and health monitoring systems that cannot be integrated with conventional wafer based complementary metal oxide semiconductor processes. Most of the current efforts to create flexible high performance devices are based on the use of organic semiconductors. However, inherent material\\'s limitations make them unsuitable for big data processing and high speed communications. The objective of my doctoral dissertation is to develop integration processes that allow the transformation of rigid high performance electronics into flexible ones while maintaining their performance and cost. In this work, two different techniques to transform inorganic complementary metal-oxide-semiconductor electronics into flexible ones have been developed using industry compatible processes. Furthermore, these techniques were used to realize flexible discrete devices and circuits which include metal-oxide-semiconductor field-effect-transistors, the first demonstration of flexible Fin-field-effect-transistors, and metal-oxide-semiconductors-based circuits. Finally, this thesis presents a new technique to package, integrate, and interconnect flexible high performance electronics using low cost additive manufacturing techniques such as 3D printing and inkjet printing. This thesis contains in depth studies on electrical, mechanical, and thermal properties of the fabricated devices.

  12. Fluorescent Nanodiamond-Gold Hybrid Particles for Multimodal Optical and Electron Microscopy Cellular Imaging.

    Science.gov (United States)

    Liu, Weina; Naydenov, Boris; Chakrabortty, Sabyasachi; Wuensch, Bettina; Hübner, Kristina; Ritz, Sandra; Cölfen, Helmut; Barth, Holger; Koynov, Kaloian; Qi, Haoyuan; Leiter, Robert; Reuter, Rolf; Wrachtrup, Jörg; Boldt, Felix; Scheuer, Jonas; Kaiser, Ute; Sison, Miguel; Lasser, Theo; Tinnefeld, Philip; Jelezko, Fedor; Walther, Paul; Wu, Yuzhou; Weil, Tanja

    2016-10-12

    There is a continuous demand for imaging probes offering excellent performance in various microscopy techniques for comprehensive investigations of cellular processes by more than one technique. Fluorescent nanodiamond-gold nanoparticles (FND-Au) constitute a new class of "all-in-one" hybrid particles providing unique features for multimodal cellular imaging including optical imaging, electron microscopy, and, and potentially even quantum sensing. Confocal and optical coherence microscopy of the FND-Au allow fast investigations inside living cells via emission, scattering, and photothermal imaging techniques because the FND emission is not quenched by AuNPs. In electron microscopy, transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) analysis of FND-Au reveals greatly enhanced contrast due to the gold particles as well as an extraordinary flickering behavior in three-dimensional cellular environments originating from the nanodiamonds. The unique multimodal imaging characteristics of FND-Au enable detailed studies inside cells ranging from statistical distributions at the entire cellular level (micrometers) down to the tracking of individual particles in subcellular organelles (nanometers). Herein, the processes of endosomal membrane uptake and release of FNDs were elucidated for the first time by the imaging of individual FND-Au hybrid nanoparticles with single-particle resolution. Their convenient preparation, the availability of various surface groups, their flexible detection modalities, and their single-particle contrast in combination with the capability for endosomal penetration and low cytotoxicity make FND-Au unique candidates for multimodal optical-electronic imaging applications with great potential for emerging techniques, such as quantum sensing inside living cells.

  13. Effects of Hybrid Fibre Reinforcement on Fire Resistance Performance and Char Morphology of Intumescent Coating

    Directory of Open Access Journals (Sweden)

    Amir N.

    2016-01-01

    Full Text Available Recent researches of fire retardant intumescent coatings reinforced by single Rockwool and single glass wool fibre at various weight percentages and lengths showed some improvements to the mechanical properties of the coatings and the char produced. Therefore, in this research the fibres were combined together in intumescent coating formulation at several weight percentages and fibre lengths to study their effects towards fire resistance performance and char morphology. The hybrid fibre reinforced intumescent coatings were subjected to two types of fire tests; Bunsen burner at 1000°C and the electric furnace at 800°C for 1 hour, respectively. Steel temperature of the coated samples during Bunsen burner test was recorded to determine the fire resistance performance. Thermal stability of the intumescent coatings and chars was determined by Thermogravimetric Analysis (TGA. The morphology of the coatings and char was then examined by using Scanning Electron Microscopy (SEM and Energy Dispersive Spectrometry (EDS was conducted to obtain elemental composition of the samples. This research concluded that long-hybrid fibre at 12-mm length and 0.6% fibre-weight produced the top performing hybrid fibre intumescent formulation. The hybrid fibres form survived at elevated temperature, hence helped to provide structure and strengthen the char with the highest fire resistance was recorded at steel temperature of 197°C.

  14. Performance Comparison of Hybrid Signed Digit Arithmetic in Efficient Computing

    Directory of Open Access Journals (Sweden)

    VISHAL AWASTHI

    2011-10-01

    Full Text Available In redundant representations, addition can be carried out in a constant time independent of the word length of the operands. Adder forms a fundamental building block in almost majority of VLSI designs. A hybrid adder can add an unsigned number to a signed-digit number and hence their efficient performance greatly determinesthe quality of the final output of the concerned circuit. In this paper we designed and compared the speed of adders by reducing the carry propagation time with the help of combined effect of improved architectures of adders and signed digit representation of number systems. The key idea is to draw out a compromise between execution time of fast adding process and area available which is often very limited. In this paper we also tried to verify the various algorithms of signed digit and hybrid signed digit adders.

  15. OPTIMIZATION OF HYBRID FINAL ADDER FOR THE HIGH PERFORMANCE MULTIPLIER

    Directory of Open Access Journals (Sweden)

    RAMKUMAR B.

    2013-04-01

    Full Text Available In this work we evaluated arrival profile of the HPM based multiplier partial products reduction tree in two ways: 1.manual delay, area calculation through logical effort, 2.ASIC implementation. Based on the arrival profile, we worked with some recently proposed optimal adders and finally we proposed an optimal hybrid adder for the final addition in HPM based parallel multiplier. This work derives some mathematical expressions to find the size of different regions in the partial product arrival profile which helps to design optimal adder for each region. This work evaluates the performance of proposed hybrid adder in terms of area, power and delay using 90nm technology. This work deals with manual calculation for 8-b and ASIC simulation of different adder designs for 8-b, 16-b, 32-b and 64-b multiplier bit sizes.

  16. The Cycle Performance of a Hybrid Carbon Battery.

    Science.gov (United States)

    Ahn, Sang-Yong; Kim, Sang-Chai; Jung, Ho-Young

    2016-02-01

    The behavior of a hybrid carbon battery is studied by using the Hg/Hg2SO4 reference electrode. The performance is confirmed in the discharge mode and a short-term cycle test. The capacities of the cell were 76.1, 60.3, 40.5, and 31.7 mAh at discharge currents of 150, 300, 600, and 900 mA, respectively. In the short-term cycle test, the capacity of the cell, 52.3 mAh at the first cycle, continuously increased to 66.7 mAh upon the fifth cycle (cut-off voltage 0.5 V in the deep cycle mode), indicating high feasibility of the hybrid carbon battery as a large-capacity energy storage system.

  17. Dynamic Performance Comparison for MPPT-PV Systems using Hybrid Pspice/Matlab Simulation

    Science.gov (United States)

    Aouchiche, N.; Becherif, M.; HadjArab, A.; Aitcheikh, M. S.; Ramadan, H. S.; Cheknane, A.

    2016-10-01

    The power generated by solar photovoltaic (PV) module depends on the surrounding irradiance and temperature. This paper presents a hybrid Matlab™/Pspice™ simulation model of PV system, combined with Cadence software SLPS. The hybridization is performed in order to gain the advantages of both simulation tools such as accuracy and efficiency in both Pspice electronic circuit and Matlab™ mathematical modelling respectively. For this purpose, the PV panel and the boost converter are developed using Pspice™ and hybridized with the mathematical Matlab™ model of maximum power point method controller (MPPT) through SLPS. The main objective is verify the significance of using the proposed hybrid simulation techniques in comparing the different MPPT algorithms such as the perturbation and observation (P&O), incremental of conductance (Inc-Cond) and counter reaction voltage using pilot cell (Pilot-Cell). Various simulations are performed under different atmospheric conditions in order to evaluate the dynamic behaviour for the system under study in terms of stability, efficiency and rapidity.

  18. Fibrous hybrid of graphene and sulfur nanocrystals for high-performance lithium-sulfur batteries.

    Science.gov (United States)

    Zhou, Guangmin; Yin, Li-Chang; Wang, Da-Wei; Li, Lu; Pei, Songfeng; Gentle, Ian Ross; Li, Feng; Cheng, Hui-Ming

    2013-06-25

    Graphene-sulfur (G-S) hybrid materials with sulfur nanocrystals anchored on interconnected fibrous graphene are obtained by a facile one-pot strategy using a sulfur/carbon disulfide/alcohol mixed solution. The reduction of graphene oxide and the formation/binding of sulfur nanocrystals were integrated. The G-S hybrids exhibit a highly porous network structure constructed by fibrous graphene, many electrically conducting pathways, and easily tunable sulfur content, which can be cut and pressed into pellets to be directly used as lithium-sulfur battery cathodes without using a metal current-collector, binder, and conductive additive. The porous network and sulfur nanocrystals enable rapid ion transport and short Li(+) diffusion distance, the interconnected fibrous graphene provides highly conductive electron transport pathways, and the oxygen-containing (mainly hydroxyl/epoxide) groups show strong binding with polysulfides, preventing their dissolution into the electrolyte based on first-principles calculations. As a result, the G-S hybrids show a high capacity, an excellent high-rate performance, and a long life over 100 cycles. These results demonstrate the great potential of this unique hybrid structure as cathodes for high-performance lithium-sulfur batteries.

  19. On Electronic Structure Engineering and Thermoelectric Performance

    OpenAIRE

    Jeong, Changwook; Lundstrom, Mark S.

    2011-01-01

    In this paper, we address the question of how to engineer the electronic structure to enhance the performance of a thermoelectric material. We examine several different materials and show that all of them, even those for which giant Seebeck coefficients have been predicted, display a value that is expected from conventional thermoelectric theory. For molecular thermoelectrics, we show that the detailed lineshape plays an important role. Finally, using III-V alloy semiconductors as a model sys...

  20. Efficient Hybrid Optimal Design Method for Power Electronics Converters

    CERN Document Server

    AUTHOR|(SzGeCERN)697719; Aguglia, Davide; Viarouge, Philippe; Cros, Jérôme

    2015-01-01

    This paper presents a novel design methodology for dimensioning optimal power-electronic converters, which is able to achieve the precision of numerical simulation-based optimization procedures, however minimizing the overall computation time. The approach is based on the utilization of analytical and frequency-domain design models for a numerical optimization process, a validation with numerical simulations of the intermediate optimal solutions, and the correction of the analytical design models precision from the numerical simulation results. This method allows using the numerical simulation in an efficient way, where typically less than ten correction iterations are required. In order to demonstrate the performances of the proposed methodology, the calculation of the control parameters for an H-bridge DC-DC converter and the optimal dimensioning of a damped output filter for a buck converter using the proposed approach is presented.

  1. Analysis of Network Parameters Influencing Performance of Hybrid Multimedia Networks

    Directory of Open Access Journals (Sweden)

    Dominik Kovac

    2013-10-01

    Full Text Available Multimedia networks is an emerging subject that currently attracts the attention of research and industrial communities. This environment provides new entertainment services and business opportunities merged with all well-known network services like VoIP calls or file transfers. Such a heterogeneous system has to be able satisfy all network and end-user requirements which are increasing constantly. Therefore the simulation tools enabling deep analysis in order to find the key performance indicators and factors which influence the overall quality for specific network service the most are highly needed. This paper provides a study on the network parameters like communication technology, routing protocol, QoS mechanism, etc. and their effect on the performance of hybrid multimedia network. The analysis was performed in OPNET Modeler environment and the most interesting results are discussed at the end of this paper

  2. Simulating Strongly Correlated Electron Systems with Hybrid Monte Carlo

    Institute of Scientific and Technical Information of China (English)

    LIU Chuan

    2000-01-01

    Using the path integral representation, the Hubbard and the periodic Anderson model on D-dimensional cubic lattice are transformed into field theories of fermions in D + 1 dimensions. These theories at half-filling possess a positive definite real symmetry fermion matrix and can be simulated using the hybrid Monte Carlo method.

  3. From hybridization theory to microarray data analysis: performance evaluation

    Directory of Open Access Journals (Sweden)

    Berger Fabrice

    2011-12-01

    Full Text Available Abstract Background Several preprocessing methods are available for the analysis of Affymetrix Genechips arrays. The most popular algorithms analyze the measured fluorescence intensities with statistical methods. Here we focus on a novel algorithm, AffyILM, available from Bioconductor, which relies on inputs from hybridization thermodynamics and uses an extended Langmuir isotherm model to compute transcript concentrations. These concentrations are then employed in the statistical analysis. We compared the performance of AffyILM and other traditional methods both in the old and in the newest generation of GeneChips. Results Tissue mixture and Latin Square datasets (provided by Affymetrix were used to assess the performances of the differential expression analysis depending on the preprocessing strategy. A correlation analysis conducted on the tissue mixture data reveals that the median-polish algorithm allows to best summarize AffyILM concentrations computed at the probe-level. Those correlation results are equivalent to the best correlations observed using popular preprocessing methods relying on intensity values. The performances of each tested preprocessing algorithm were quantified using the Latin Square HG-U133A dataset, thanks to the comparison of differential analysis results with the list of spiked genes. The figures of merit generated illustrates that the performances associated to AffyILM(medianpolish, inferred from the present statistical analysis, are comparable to the best performing strategies previously reported. Conclusions Converting probe intensities to estimates of target concentrations prior to the statistical analysis, AffyILM(medianpolish is one of the best performing strategy currently available. Using hybridization theory, probe-level estimates of target concentrations should be identically distributed. In the future, a probe-level multivariate analysis of the concentrations should be compared to the univariate analysis of

  4. Performance analysis of a hybrid fingerprint extracted from optical coherence tomography fingertip scans

    CSIR Research Space (South Africa)

    Darlow, Luke N

    2016-06-01

    Full Text Available International Conference on Biometrics (ICB), 13-16 June 2016, Halmstad, Sweden Performance analysis of a hybrid fingerprint extracted from optical coherence tomography fingertip scans Darlow LN Connan J Singh A ABSTRACT: The Hybrid fingerprint is a...

  5. More stable hybrid organic solar cells deposited on amorphous Si electron transfer layer

    Energy Technology Data Exchange (ETDEWEB)

    Samiee, Mehran; Modtland, Brian; Dalal, Vikram L., E-mail: vdalal@iastate.edu [Iowa State University, Dept. of Electrical and Computer Engineering, Ames, Iowa 50011 (United States); Aidarkhanov, Damir [Nazarbayev University, Astana (Kazakhstan)

    2014-05-26

    We report on defect densities, performance, and stability of organic/inorganic hybrid solar cells produced using n-doped inorganic amorphous silicon-carbide layers as the electron transport layer (ETL). The organic material was poly-3-hexyl-thiophene (P3HT) and heterojunction was formed using phenyl-C{sub 71}-Butyric-Acid-Methyl Ester (PCBM). For comparison, inverted solar cells fabricated using Cs{sub 2}CO{sub 3} as ETL were fabricated. Defect densities and subgap quantum efficiency curves were found to be nearly identical for both types of cells. The cells were subjected to 2xsun illumination and it was found that the cells produced using doped a-Si as ETL were much more stable than the cells produced using Cs{sub 2}CO{sub 3}.

  6. The Detection of Defects in Optical Fibers Using a Hybrid Opto-electronic Correlator

    Institute of Scientific and Technical Information of China (English)

    LIU Yange; LIU Wei; ZHANG Yimo; ZHOU Ge

    2000-01-01

    A hybrid opto-electronic correlator for detecting defects in optical fibers is proposed. After the light from a He-Ne laser being expanded and filtered it is not collimated but directly passes a Fourier transform lens and illuminates a reference fiber and a test fiber at the same input plane. The Fourier transform spectrum of the two fibers is therefore obtained at the rear focal plane of the lens, where it is sampled via a CCD array connected with a computer through a frame grabber. The computer performs filter, inverse Fourier transform and setting threshold operation on classification. The system is an equivalent of joint transform correlator with a Fourier lens of long focal length. The experiment results for optical fibers having incoordinate defects are presented. The results indicate that the system can be used for fiber defect detection, and has the advantages of high identification, compact configuration, easy adjustment and flexible manipulation.

  7. Slow electron energy balance for hybrid models of direct-current glow discharges

    Science.gov (United States)

    Eliseev, S. I.; Bogdanov, E. A.; Kudryavtsev, A. A.

    2017-09-01

    In this paper, we present the formulation of slow electron energy balance for hybrid models of direct current (DC) glow discharge. Electrons originating from non-local ionization (secondary) contribute significantly to the energy balance of slow electrons. An approach towards calculating effective energy brought by a secondary electron to the group of slow electrons by means of Coulomb collisions is suggested. The value of effective energy shows a considerable dependence on external parameters of a discharge, such as gas pressure, type, and geometric parameters. The slow electron energy balance was implemented into a simple hybrid model that uses analytical formulation for the description of non-local ionization by fast electrons. Simulations of short (without positive column) DC glow discharge in argon are carried out for a range of gas pressures. Comparison with experimental data showed generally good agreement in terms of current-voltage characteristics, electron density, and electron temperature. Simulations also capture the trend of increasing electron density with decreasing pressure observed in the experiment. Analysis shows that for considered conditions, the product of maximum electron density ne and electron temperature Te in negative glow is independent of gas pressure and depends on the gas type, cathode material, and discharge current. Decreasing gas pressure reduces the heating rate of slow electrons during Coulomb collisions with secondary electrons, which leads to lower values of Te and, in turn, higher maximum ne.

  8. High Performance Hybrid Energy Storage with Potassium Ferricyanide Redox Electrolyte.

    Science.gov (United States)

    Lee, Juhan; Choudhury, Soumyadip; Weingarth, Daniel; Kim, Daekyu; Presser, Volker

    2016-09-14

    We demonstrate stable hybrid electrochemical energy storage performance of a redox-active electrolyte, namely potassium ferricyanide in aqueous media in a supercapacitor-like setup. Challenging issues associated with such a system are a large leakage current and high self-discharge, both stemming from ion redox shuttling through the separator. The latter is effectively eliminated when using an ion exchange membrane instead of a porous separator. Other critical factors toward the optimization of a redox-active electrolyte system, especially electrolyte concentration and volume of electrolyte, have been studied by electrochemical methods. Finally, excellent long-term stability is demonstrated up to 10 000 charge/discharge cycles at 1.2 and 1.8 V, with a broad maximum stability window of up to 1.8 V cell voltage as determined via cyclic voltammetry. An energy capacity of 28.3 Wh/kg or 11.4 Wh/L has been obtained from such cells, taking the nonlinearity of the charge-discharge profile into account. The power performance of our cell has been determined to be 7.1 kW/kg (ca. 2.9 kW/L or 1.2 kW/m(2)). These ratings are higher compared to the same cell operated in aqueous sodium sulfate. This hybrid electrochemical energy storage system is believed to find a strong foothold in future advanced energy storage applications.

  9. Decal Electronics: Printable Packaged with 3D Printing High-Performance Flexible CMOS Electronic Systems

    KAUST Repository

    Sevilla, Galo T.

    2016-10-14

    High-performance complementary metal oxide semiconductor electronics are flexed, packaged using 3D printing as decal electronics, and then printed in roll-to-roll fashion for highly manufacturable printed flexible high-performance electronic systems.

  10. Tunable hybridization of electronic states of graphene and a metal surface

    OpenAIRE

    Gruneis, Alexander; Vyalikh, Denis

    2008-01-01

    We present an approach to monitor and control the strength of the hybridization between electronic states of graphene and metal surfaces. Inspecting the distribution of the $\\pi$ band in a high-quality graphene layer synthesized on Ni(111) by angle-resolved photoemission, we observe a new "kink" feature which indicates a strong hybridization between $\\pi$ and \\textit{d} states of graphene and nickel, respectively. Upon deposition and gradual intercalation of potassium atoms into the graphene/...

  11. Electron field emission characteristics of graphene/carbon nanotubes hybrid field emitter

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Leifeng, E-mail: chlf@hdu.edu.cn [College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); He, Hong; Yu, Hua; Cao, Yiqi [College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); Lei, Da, E-mail: leida126@126.com [Ordos College of Inner Mongolia University, Inner Mongolia University, Ordos 017000 (China); Menggen, QiQiGe [Ordos College of Inner Mongolia University, Inner Mongolia University, Ordos 017000 (China); Wu, Chaoxing; Hu, Liqin [College of Physics and Information Engineering, Fuzhou University, Fuzhou 350002 (China)

    2014-10-15

    The graphene (GP) and multi-walled carbon nanotubes (MCNTs) hybrid nanostructure emitter was constructed by a larger scale electrophoretic deposition (EPD) method. The field emission (FE) performance of the hybrid emitter is greatly improved compared with that of only GP or MCNTs emitter. The low turn-on electric field (EF), the low threshold EF and the reliability FE properties are obtained from the hybrid emitter. The better FE properties result from the improved electrical properties. For further enhancement FE of hybrids, Ag Nanoparticles (NPs) were decorated on the hybrids and FE characteristics were also studied. These studies indicate that we can use the hybrid nanostructure to improve conductivity and contact resistance, which results in enhancement of the FE properties.

  12. Electron beam energy stabilization using a neural network hybrid controller at the Australian Synchrotron Linac.

    Energy Technology Data Exchange (ETDEWEB)

    Meier, E.; Morgan, M. J.; Biedron, S. G.; LeBlanc, G.; Wu, J. (OTD-ESE); (Monash Univ.); (Australian Synchrotron Project); (SLAC National Accelerator Lab.)

    2009-01-01

    This paper describes the implementation of a neural network hybrid controller for energy stabilization at the Australian Synchrotron Linac. The structure of the controller consists of a neural network (NNET) feed forward control, augmented by a conventional Proportional-Integral (PI) feedback controller to ensure stability of the system. The system is provided with past states of the machine in order to predict its future state, and therefore apply appropriate feed forward control. The NNET is able to cancel multiple frequency jitter in real-time. When it is not performing optimally due to jitter changes, the system can successfully be augmented by the PI controller to attenuate the remaining perturbations. With a view to control the energy and bunch length at the FERMI{at}Elettra Free Electron Laser (FEL), the present study considers a neural network hybrid feed forward-feedback type of control to rectify limitations related to feedback systems, such as poor response for high jitter frequencies or limited bandwidth, while ensuring robustness of control. The Australian Synchrotron Linac is equipped with a beam position monitor (BPM), that was provided by Sincrotrone Trieste from a former transport line thus allowing energy measurements and energy control experiments. The present study will consequently focus on correcting energy jitter induced by variations in klystron phase and voltage.

  13. Polymer-metal hybrid transparent electrodes for flexible electronics

    National Research Council Canada - National Science Library

    Kang, Hongkyu; Jung, Suhyun; Jeong, Soyeong; Kim, Geunjin; Lee, Kwanghee

    2015-01-01

    Despite nearly two decades of research, the absence of ideal flexible and transparent electrodes has been the largest obstacle in realizing flexible and printable electronics for future technologies...

  14. Preparation and property of a novel soluble electron transport POSS-based hybrid material

    Institute of Scientific and Technical Information of China (English)

    Xin Wang; Juan Shen; Jin Cui Wu; Min Fang; Hong Yao Xu

    2008-01-01

    A novel POSS-based organic/inorganic hybrid covalently attached at molecular level, 2-(4-(allyloxy)phenyl)-5-(4-(octyloxy)phenyl)-1,3,4-oxadiazole-POSS (6) (abbreviated as oxadiazole-POSS) was synthesized by Pt (dcp) catalyst. The hybrid was soluble in common organic solvents such as CHCl3, toluene, C2H4Cl2, and THF. Its structures and properties were characterized and evaluated with FTIR, 1H NMR, 13C NMR, 29Si NMR, EA, TGA, DSC, GPC, and CV, respectively. The results show that the novel hybrid possesses high thermal stability and good electron injection ability.

  15. Hybrid nanowire ion-to-electron transducers for integrated bioelectronic circuitry (Conference Presentation)

    Science.gov (United States)

    Carrad, Damon J.; Mostert, Bernard; Meredith, Paul; Micolich, Adam P.

    2016-09-01

    A key task in bioelectronics is the transduction between ionic/protonic signals and electronic signals at high fidelity. This is a considerable challenge since the two carrier types exhibit intrinsically different physics. We present our work on a new class of organic-inorganic transducing interface utilising semiconducting InAs and GaAs nanowires directly gated with a proton transporting hygroscopic polymer consisting of undoped polyethylene oxide (PEO) patterned to nanoscale dimensions by a newly developed electron-beam lithography process [1]. Remarkably, we find our undoped PEO polymer electrolyte gate dielectric [2] gives equivalent electrical performance to the more traditionally used LiClO4-doped PEO [3], with an ionic conductivity three orders of magnitude higher than previously reported for undoped PEO [4]. The observed behaviour is consistent with proton conduction in PEO. We attribute our undoped PEO-based devices' performance to the small external surface and high surface-to-volume ratio of both the nanowire conducting channel and patterned PEO dielectric in our devices, as well as the enhanced hydration afforded by device processing and atmospheric conditions. In addition to studying the basic transducing mechanisms, we also demonstrate high-fidelity ionic to electronic conversion of a.c. signals at frequencies up to 50 Hz. Moreover, by combining complementary n- and p-type transducers we demonstrate functional hybrid ionic-electronic circuits can achieve logic (NOT operation), and with some further engineering of the nanowire contacts, potentially also amplification. Our device structures have significant potential to be scaled towards realising integrated bioelectronic circuitry. [1] D.J. Carrad et al., Nano Letters 14, 94 (2014). [2] D.J. Carrad et al., Manuscript in preparation (2016). [3] S.H. Kim et al., Advanced Materials 25, 1822 (2013). [4] S.K. Fullerton-Shirey et al., Macromolecules 42, 2142 (2009).

  16. Interaction of runaway electrons with lower hybrid waves via anomalous Doppler broadening

    Science.gov (United States)

    Martín-Solís, J. R.; Sánchez, R.; Esposito, B.

    2002-05-01

    Due to the relativistic decrease of the electron cyclotron frequency, a cyclotron resonance may appear between runaway electrons and lower hybrid waves. A single particle description of the runaway dynamics [J. R. Martín-Solís et al., Phys. Plasmas 5, 2370 (1998)] is extended to analyze the effect of the interaction of runaway electrons with lower hybrid waves via anomalous Doppler broadening. The conditions under which the resonant interaction can play a role in limiting the runaway energy are established and it is shown that, under typical lower hybrid current drive operation parameters, an efficient wave-particle coupling may occur. Observations of a fast pitch angle scattering event during the current decay phase of Ohmic discharges in the Toroidal Experiment for Technically Oriented Research (TEXTOR) [R. J. E. Jaspers, Ph.D. thesis, Technical University Eindhoven (1995)] are interpreted in terms of such interaction.

  17. A "Hybrid" Bacteriology Course: The Professor's Design and Expectations; The Students' Performance and Assessment

    Directory of Open Access Journals (Sweden)

    Steven Krawiec

    2009-12-01

    Full Text Available A basic bacteriology course was offered in two successive academic years, first in a conventional format and subsequently as a "hybrid" course. The latter combined (i online presentation of content, (ii an emphasis on online resources, (iii thrice-weekly, face-to-face conversations to advance understanding, and (iv frequent student postings on an electronic discussion board. We compared the two courses through statistical analysis of student performances on the final examinations and the course overall and student assessment of teaching. The data indicated that there was no statistical difference in performance on the final examinations or the course overall. Responses on an instrument of evaluation revealed that students less strongly affirmed the following measures in the hybrid course: (i The amount of work was appropriate for the credit received, (ii Interactions between students and instructor were positive, (iii I learned a great deal in this course, and (iv I would recommend this course to other students. We recommend clear direction about active learning tasks and relevant feedback to enhance learning in a hybrid course.

  18. Paired-pulse facilitation achieved in protonic/electronic hybrid indium gallium zinc oxide synaptic transistors

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Li Qiang, E-mail: guoliqiang@ujs.edu.cn; Ding, Jian Ning; Huang, Yu Kai [Micro/Nano Science & Technology Center, Jiangsu University, Zhenjiang, 212013 (China); Zhu, Li Qiang, E-mail: lqzhu@nimte.ac.cn [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

    2015-08-15

    Neuromorphic devices with paired pulse facilitation emulating that of biological synapses are the key to develop artificial neural networks. Here, phosphorus-doped nanogranular SiO{sub 2} electrolyte is used as gate dielectric for protonic/electronic hybrid indium gallium zinc oxide (IGZO) synaptic transistor. In such synaptic transistors, protons within the SiO{sub 2} electrolyte are deemed as neurotransmitters of biological synapses. Paired-pulse facilitation (PPF) behaviors for the analogous information were mimicked. The temperature dependent PPF behaviors were also investigated systematically. The results indicate that the protonic/electronic hybrid IGZO synaptic transistors would be promising candidates for inorganic synapses in artificial neural network applications.

  19. Performance Analysis of a Hybrid District Heating System

    DEFF Research Database (Denmark)

    Mikulandric, Robert; Krajačić, Goran; Duic, Neven

    2015-01-01

    Hybridisation of district heating systems can contribute to more efficient heat generation through cogeneration power plants or through the share increase of renewable energy sources in total energy consumption while reducing negative aspects of particular energy source utilisation. In this work......, the performance of a hybrid district energy system for a small town in Croatia has been analysed. Mathematical model for process analysis and optimisation algorithm for optimal system configuration has been developed and described. The main goal of the system optimisation is to reduce heat production costs....... Several energy sources for heat production have been considered in 8 different simulation cases. Simulation results show that the heat production costs could be reduced with introduction of different energy systems into an existing district heating system. Renewable energy based district heating systems...

  20. Effects of optical backscattering on silicon photonic hybrid laser performance

    Science.gov (United States)

    Pacradouni, V.; Klein, J.; Pond, J.

    2016-04-01

    We present numerical results on the effect of backscattering at the junctions of double bus ring resonators in a Vernier ring hybrid laser design. The structure is comprised off a pair of III-V gain media evanescently coupled to a silicon on insulator racetrack comprised of a pair of double bus ring resonators coupled together through straight and flared waveguide sections. We show how the small backscattering at the ring resonator junctions has the effect of splitting and shifting the resonances off the clockwise and counter clockwise propagating modes thereby modifying the feedback spectrum from the ideal case. We then simulate results such as light current (LI) curves, relative intensity noise (RIN) and laser spectrum, and compare the laser performance including backscattering effects with the ideal case.

  1. Platinum nanoparticle interlayer promoted improvement in photovoltaic performance of silicon/PEDOT:PSS hybrid solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Xiao-Qing; Liu, L.F., E-mail: lifeng.liu@inl.int

    2015-01-15

    Inorganic–organic hybrid solar cells have attracted considerable interest in recent years for their low production cost, good mechanical flexibility and ease of processing of polymer films over a large area. Particularly, silicon/conducting polymer hybrid solar cells are extensively investigated and widely believed to be a low-cost alternative to the crystalline silicon solar cells. However, the power conversion efficiency of silicon/conducting polymer solar cells remains low in case hydrogen-terminated silicon is used. In this paper, we report that by introducing a platinum nanoparticle interlayer between the hydrogen-terminated silicon and the conducting polymer poly(3,4-ethylenedioxy thiophene):poly(styrene sulfonate), namely PEDOT:PSS, the power conversion efficiency of the resulting Si/PEDOT:PSS hybrid solar cells can be improved by a factor of 2–3. The possible mechanism responsible for the improvement has been investigated using different techniques including impedance spectroscopy, Mott–Schottky analysis and intensity modulated photocurrent/photovoltage spectroscopy (IMPS/IMVS). The results show that with a platinum nanoparticle interlayer, both the series resistance and charge transport/transfer resistance of the Si/PEDOT:PSS hybrid solar cells are reduced leading to an increased short circuit current density, and the built-in voltage at the space charge region is raised facilitating electron-hole separation. Moreover, the lifetime of charge carriers in the Si/PEDOT:PSS solar cells is extended, namely, the recombination is effectively suppressed which also contributes to the improvement of photovoltaic performance. - Graphical abstract: A platinum nanoparticle interlayer electrolessly deposited between the n-Si:H and PEDOT:PSS can markedly improve the photovoltaic performance of the resulting Si/PEDOT:PSS hybrid solar cells. - Highlights: • A Pt nanoparticle layer is introduced between the Si and PEDOT:PSS in hybrid cells. • The Pt interlayer

  2. Nickel cobalt oxide/carbon nanotubes hybrid as a high-performance electrocatalyst for metal/air battery

    Science.gov (United States)

    Zhang, Hui; Qiao, Hang; Wang, Haiyan; Zhou, Nan; Chen, Jiajie; Tang, Yougen; Li, Jingsha; Huang, Chenghuan

    2014-08-01

    High-performance, low cost catalyst for oxygen reduction reaction (ORR) remains a big challenge. Herein, nanostructured NiCo2O4/CNTs hybrid was proposed as a high-performance catalyst for metal/air battery for the first time. The well-formed NiCo2O4/CNTs hybrid was studied by steady-state linear polarization curves and galvanostatic discharge curves in comparison with CNTs-free NiCo2O4 and commercial carbon-supported Pt. Because of the synergistic effect, NiCo2O4/CNTs hybrid exhibited significant improvement of catalytic performance in comparison with NiCo2O4 or CNTs alone, even outperforming Pt/C hybrid in ORR process. In addition, the benefits of Ni incorporation were demonstrated by the improved catalytic performance of NiCo2O4/CNTs compared to Co3O4/CNTs, which should be attributed to improved electrical conductivity and new, highly efficient, active sites created by Ni cation incorporation into the spinel structure. NiCo2O4/CNTs hybrid could be used as a promising catalyst for high power metal/air battery.High-performance, low cost catalyst for oxygen reduction reaction (ORR) remains a big challenge. Herein, nanostructured NiCo2O4/CNTs hybrid was proposed as a high-performance catalyst for metal/air battery for the first time. The well-formed NiCo2O4/CNTs hybrid was studied by steady-state linear polarization curves and galvanostatic discharge curves in comparison with CNTs-free NiCo2O4 and commercial carbon-supported Pt. Because of the synergistic effect, NiCo2O4/CNTs hybrid exhibited significant improvement of catalytic performance in comparison with NiCo2O4 or CNTs alone, even outperforming Pt/C hybrid in ORR process. In addition, the benefits of Ni incorporation were demonstrated by the improved catalytic performance of NiCo2O4/CNTs compared to Co3O4/CNTs, which should be attributed to improved electrical conductivity and new, highly efficient, active sites created by Ni cation incorporation into the spinel structure. NiCo2O4/CNTs hybrid could be used as a

  3. Nanoscale Structure of Self-Assembling Hybrid Materials of Inorganic and Electronically Active Organic Phases

    Energy Technology Data Exchange (ETDEWEB)

    Sofos, M.; Goswami, D.A. Stone D.K.; Okasinski, J.S.; Jin, H.; Bedzyk, M.J.; Stupp, S.I. (NWU)

    2008-10-06

    Hybrid materials with nanoscale structure that incorporates inorganic and organic phases with electronic properties offer potential in an extensive functional space that includes photovoltaics, light emission, and sensing. This work describes the nanoscale structure of model hybrid materials with phases of silica and electronically active bola-amphiphile assemblies containing either oligo(p-phenylene vinylene) or oligo(thiophene) segments. The hybrid materials studied here were synthesized by evaporation-induced self-assembly and characterized by X-ray scattering techniques. Grazing-incidence X-ray scattering studies of these materials revealed the formation of two-dimensional hexagonally packed cylindrical micelles of the organic molecules with diameters between 3.1 and 3.6 nm and cylindrical axes parallel to the surface. During the self-assembly process at low pH, the cylindrical aggregates of conjugated molecules become surrounded by silica giving rise to a hybrid structure with long-range order. Specular X-ray reflectivity confirmed the long-range periodicity of the hybrid films within a specific range of molar ratios of tetraethyl orthosilicate to cationic amphiphile. We did not observe any long-range ordering in fully organic analogues unless quaternary ammonium groups were replaced by tertiary amines. These observations suggest that charge screening in these biscationic conjugated molecules by the mineral phase is a key factor in the evolution of long range order in the self-assembling hybrids.

  4. A Hybrid Fuzzy Model for Lean Product Development Performance Measurement

    Science.gov (United States)

    Osezua Aikhuele, Daniel; Mohd Turan, Faiz

    2016-02-01

    In the effort for manufacturing companies to meet up with the emerging consumer demands for mass customized products, many are turning to the application of lean in their product development process, and this is gradually moving from being a competitive advantage to a necessity. However, due to lack of clear understanding of the lean performance measurements, many of these companies are unable to implement and fully integrated the lean principle into their product development process. Extensive literature shows that only few studies have focus systematically on the lean product development performance (LPDP) evaluation. In order to fill this gap, the study therefore proposed a novel hybrid model based on Fuzzy Reasoning Approach (FRA), and the extension of Fuzzy-AHP and Fuzzy-TOPSIS methods for the assessment of the LPDP. Unlike the existing methods, the model considers the importance weight of each of the decision makers (Experts) since the performance criteria/attributes are required to be rated, and these experts have different level of expertise. The rating is done using a new fuzzy Likert rating scale (membership-scale) which is designed such that it can address problems resulting from information lost/distortion due to closed-form scaling and the ordinal nature of the existing Likert scale.

  5. Performance of a hybrid chemical/mechanical heat pump

    Science.gov (United States)

    Silvestri, John J.; Scaringe, Robert P.; Grzyll, Lawrence R.

    1990-01-01

    The authors present the design and preliminary results of the performance of a hybrid chemical/mechanical, low-lift (20 C) heat pump. Studies have indicated that this heat pump has several advantages over the traditional single fluid vapor compression (reverse Rankine) heat pump. Included in these benefits are: 1) increased COPc due to the approximation of the cycle to the Lorenz cycle and due to the availability of the heat of solution, along with the heat of vaporization, to provide cooling; and 2) ease of variation in system cooling capacity by changing the fluid composition. The system performance is predicted for a variety of refrigerant-absorbent pairs. Cooling capacity is determined for systems operating with ammonia as the refrigerant and lithium nitrate and sodium thiocyanate as the absorbents and also with water as the refrigerant and magnesium chloride, potassium hydroxide, lithium bromide, sodium hydroxide, and sulfuric acid as the absorbents. Early indications have shown that the systems operating with water as the refrigerant operate at 2-4 times the capacity of the ammonia-refrigerant-based systems. Using existing working fluids in the proposed innovative design, a coefficient-of-performance improvement of 21 percent is possible when compared to the best vapor compression systems analyzed.

  6. Performance of a hybrid chemical/mechanical heat pump

    Science.gov (United States)

    Silvestri, John J.; Scaringe, Robert P.; Grzyll, Lawrence R.

    1990-01-01

    The authors present the design and preliminary results of the performance of a hybrid chemical/mechanical, low-lift (20 C) heat pump. Studies have indicated that this heat pump has several advantages over the traditional single fluid vapor compression (reverse Rankine) heat pump. Included in these benefits are: 1) increased COPc due to the approximation of the cycle to the Lorenz cycle and due to the availability of the heat of solution, along with the heat of vaporization, to provide cooling; and 2) ease of variation in system cooling capacity by changing the fluid composition. The system performance is predicted for a variety of refrigerant-absorbent pairs. Cooling capacity is determined for systems operating with ammonia as the refrigerant and lithium nitrate and sodium thiocyanate as the absorbents and also with water as the refrigerant and magnesium chloride, potassium hydroxide, lithium bromide, sodium hydroxide, and sulfuric acid as the absorbents. Early indications have shown that the systems operating with water as the refrigerant operate at 2-4 times the capacity of the ammonia-refrigerant-based systems. Using existing working fluids in the proposed innovative design, a coefficient-of-performance improvement of 21 percent is possible when compared to the best vapor compression systems analyzed.

  7. The electronic transport characteristics of hybridized hexagon beryllium sulfide and graphene nanoribbons

    Science.gov (United States)

    Wang, Lihua; Ding, Bingjun; Guo, Yong

    2017-01-01

    Hybridized Z-BexSyCz (x + y + z = 16) systems connected by zigzag beryllium-sulfide (BeS) and graphene nanoribbons are theoretically designed, and their electronic transport characteristics are explored by first-principles approach. For the hybridized systems with unequal number of x and y, i.e. z is an odd number, an exceptional negative differential resistance (NDR) property occurs. However, for the hybridized systems including an even number of zigzag carbon chains, namely x equal to y, an interesting current-limited behavior happens. Meanwhile, the NDR phenomenon disappears. The spin transport properties of these hybridized Z-BexSyCz systems with parallel magnetism configuration also reveal the above odd-even dependence conductance behavior.

  8. Using k-alpha emission to determine fast electron spectra using the Hybrid code ZEPHYROS

    CERN Document Server

    White, Thomas; Gregori, Gianluca

    2014-01-01

    A high intensity laser-solid interaction invariably drives a non-thermal fast electron current through the target, however characterizing these fast electron distributions can prove difficult. An understanding of how these electrons propagate through dense materials is of fundamental interest and has applications relevant to fast ignition schemes and ion acceleration. Here, we utilize an upgraded version of the Hybrid code ZEPHYROS to demonstrate how the resulting k-alpha emission from such an interaction can be used as a diagnostic to obtain the characteristic temperature, divergence and total energy of the fast electron population.

  9. My ENG 102 Class Has Gone to HEC: Creating the Hybrid Electronic Course.

    Science.gov (United States)

    Ross, Jeffrey

    In this paper, a college English professor shares his teaching experiences in a Hybrid Electronic Course (HEC), which combined traditional classroom meetings with e-mail-based workshops. The paper includes a general description of the course, the instructor's daily journals throughout the course, and his reflections following the course. Many of…

  10. Oxide nanomembrane hybrids with enhanced mechano- and thermo-sensitivity for semitransparent epidermal electronics.

    Science.gov (United States)

    Park, Minjoon; Do, Kyungsik; Kim, Jaemin; Son, Donghee; Koo, Ja Hoon; Park, Jinkyung; Song, Jun-Kyul; Kim, Ji Hoon; Lee, Minbaek; Hyeon, Taeghwan; Kim, Dae-Hyeong

    2015-05-01

    Oxide nanomembrane hybrids with enhanced mechano- and thermo-sensitivity for semitransparent epidermal electronics are developed. The use of nanomaterials (single wall nanotubes and silver nanoparticles) embedded in the oxide nanomembranes significantly enhances mechanical and thermal sensitivities. These mechanical and thermal sensors are utilized in wheelchair control and hypothermia detection, which are useful for patients with strokes.

  11. Bosch automotive electrics and automotive electronics systems and components, networking and hybrid drive

    CERN Document Server

    2014-01-01

    The significance of electrical and electronic systems has increased considerably in the last few years and this trend is set to continue. The characteristics feature of innovative systems is the fact that they can work together in a network. This requires powerful bus systems that the electronic control units can use to exchange information. Networking and the various bus systems used in motor vehicles are the prominent new topic in the 5th edition of the "Automotive Electric, Automotive Electronics" technical manual. The existing chapters have also been updated, so that this new edition brings the reader up to date on the subjects of electrical and electronic systems in the motor vehicle. Content Electrical and electronical systems – Basic principles of networking - Examples of networked vehicles – Bus systems – Architecture of electronic systems – Mechatronics – Elektronics – Electronic control Units – Software – Sensors – Actuators – Hybrid drives – Vehicle electrical system – Start...

  12. Demand Response Performance of GE Hybrid Heat Pump Water Heater

    Energy Technology Data Exchange (ETDEWEB)

    Widder, Sarah H.; Parker, Graham B.; Petersen, Joseph M.; Baechler, Michael C.

    2013-07-01

    This report describes a project to evaluate and document the DR performance of HPWH as compared to ERWH for two primary types of DR events: peak curtailments and balancing reserves. The experiments were conducted with GE second-generation “Brillion”-enabled GeoSpring hybrid water heaters in the PNNL Lab Homes, with one GE GeoSpring water heater operating in “Standard” electric resistance mode to represent the baseline and one GE GeoSpring water heater operating in “Heat Pump” mode to provide the comparison to heat pump-only demand response. It is expected that “Hybrid” DR performance, which would engage both the heat pump and electric elements, could be interpolated from these two experimental extremes. Signals were sent simultaneously to the two water heaters in the side-by-side PNNL Lab Homes under highly controlled, simulated occupancy conditions. This report presents the results of the evaluation, which documents the demand-response capability of the GE GeoSpring HPWH for peak load reduction and regulation services. The sections describe the experimental protocol and test apparatus used to collect data, present the baselining procedure, discuss the results of the simulated DR events for the HPWH and ERWH, and synthesize key conclusions based on the collected data.

  13. Surfactant-activated lipase hybrid nanoflowers with enhanced enzymatic performance

    Science.gov (United States)

    Cui, Jiandong; Zhao, Yamin; Liu, Ronglin; Zhong, Cheng; Jia, Shiru

    2016-01-01

    Increasing numbers of materials have been extensively used as platforms for enzyme immobilization to improve catalytic performance. However, activity of the most of the enzymes was declined after immobilization. Here, we develop a surfactant-activated lipase-inorganic flowerlike hybrid nanomaterials with rational design based on interfacial activation and self-assembly. The resulting surfactant-activated lipase-inorganic hybird nanoflower (activated hNF-lipase) exhibited 460% and 200% higher activity than native lipase and conventional lipase-inorganic hybird nanoflower (hNF-lipase). Furthermore, the activated hNF-lipase displayed good reusability due to its monodispersity and mechanical properties, and had excellent long-time stability. The superior catalytic performances were attributed to both the conformational modulation of surfactants and hierarchical structure of nanoflowers, which not only anchored lipases in an active form, but also decreased the enzyme-support negative interaction and mass-transfer limitations. This new biocatalytic system is promising to find widespread use in applications related to biomedicine, biosensor, and biodiesel. PMID:27297609

  14. A logistical model for performance evaluations of hybrid generation systems

    Energy Technology Data Exchange (ETDEWEB)

    Bonanno, F.; Consoli, A.; Raciti, A. [Univ. of Catania (Italy). Dept. of Electrical, Electronic, and Systems Engineering; Lombardo, S. [Schneider Electric SpA, Torino (Italy)

    1998-11-01

    In order to evaluate the fuel and energy savings, and to focus on the problems related to the exploitation of combined renewable and conventional energies, a logistical model for hybrid generation systems (HGS`s) has been prepared. A software package written in ACSL, allowing easy handling of the models and data of the HGS components, is presented. A special feature of the proposed model is that an auxiliary fictitious source is introduced in order to obtain the power electric balance at the busbars during the simulation state and, also, in the case of ill-sized components. The observed imbalance powers are then used to update the system design. As a case study, the simulation program is applied to evaluate the energetic performance of a power plant relative to a small isolated community, and island in the Mediterranean Sea, in order to establish the potential improvement achievable via an optimal integration of renewable energy sources in conventional plants. Evaluations and comparisons among different-sized wind, photovoltaic, and diesel groups, as well as of different management strategies have been performed using the simulation package and are reported and discussed in order to present the track followed to select the final design.

  15. Hybrid optical and electronic laser locking using spectral hole burning

    CERN Document Server

    Farr, Warrick G; Ledingham, Patrick M; Korystov, Dmitry; Longdell, Jevon J

    2010-01-01

    We report on a narrow linewidth laser diode system that is stabilized using both optical and electronic feedback to a spectral hole in cryogenic Tm:YAG. The laser system exhibits very low phase noise. The spectrum of the beat signal between two lasers, over millisecond timescales, is either Fourier limited or limited by the -111dBc/Hz noise floor. The resulting laser is well suited to quantum optics and sensing applications involving rare earth ion dopants.

  16. Real-world environmental performance of hybrid vehicles

    NARCIS (Netherlands)

    Winkel, R.G.; Hendriksen, P.; Vermeulen, R.J.; Foster, D.L.

    2001-01-01

    With the further development and market introduction of hybrid vehicle technologies in recent years we are now at a stage where we can test whether the proclaimed advantages of hybrid propulsion in terms of fuel efficiency and emission reduction are actually realised. An important issue is that

  17. Real-world environmental performance of hybrid vehicles

    NARCIS (Netherlands)

    Winkel, R.G.; Hendriksen, P.; Vermeulen, R.J.; Foster, D.L.

    2001-01-01

    With the further development and market introduction of hybrid vehicle technologies in recent years we are now at a stage where we can test whether the proclaimed advantages of hybrid propulsion in terms of fuel efficiency and emission reduction are actually realised. An important issue is that sign

  18. Transmission electron microscopy of unstained hybrid Au nanoparticles capped with PPAA (plasma-poly-allylamine): structure and electron irradiation effects.

    Science.gov (United States)

    Gontard, Lionel C; Fernández, Asunción; Dunin-Borkowski, Rafal E; Kasama, Takeshi; Lozano-Pérez, Sergio; Lucas, Stéphane

    2014-12-01

    Hybrid (organic shell-inorganic core) nanoparticles have important applications in nanomedicine. Although the inorganic components of hybrid nanoparticles can be characterized readily using conventional transmission electron microscopy (TEM) techniques, the structural and chemical arrangement of the organic molecular components remains largely unknown. Here, we apply TEM to the physico-chemical characterization of Au nanoparticles that are coated with plasma-polymerized-allylamine, an organic compound with the formula C3H5NH2. We discuss the use of energy-filtered TEM in the low-energy-loss range as a contrast enhancement mechanism for imaging the organic shells of such particles. We also study electron-beam-induced crystallization and amorphization of the shells and the formation of graphitic-like layers that contain both C and N. The resistance of the samples to irradiation by high-energy electrons, which is relevant for optical tuning and for understanding the degree to which such hybrid nanostructures are stable in the presence of biomedical radiation, is also discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Imaging performance of the hybrid pixel detectors XPAD3-S.

    Science.gov (United States)

    Brunner, F Cassol; Clemens, J C; Hemmer, C; Morel, C

    2009-03-21

    Hybrid pixel detectors, originally developed for tracking particles in high-energy physics experiments, have recently been used in material sciences and macromolecular crystallography. Their capability to count single photons and to apply a threshold on the photon energy suggests that they could be optimal digital x-ray detectors in low energy beams such as for small animal computed tomography (CT). To investigate this issue, we have studied the imaging performance of photon counting hybrid pixel detectors based on the XPAD3-S chip. Two detectors are considered, connected either to a Si or to a CdTe sensor, the latter being of interest for its higher efficiency. Both a standard 'International Electrotechnical Commission' (IEC) mammography beam and a beam used for mouse CT results published in the literature are employed. The detector stability, linearity and noise are investigated as a function of the dose for several imaging exposures ( approximately 0.1-400 microGy). The perfect linearity of both detectors is confirmed, but an increase in internal noise for counting statistics higher than approximately 5000 photons has been found, corresponding to exposures above approximately 110 microGy and approximately 50 microGy for the Si and CdTe sensors, respectively. The noise power spectrum (NPS), the modulation transfer function (MTF) and the detective quantum efficiency (DQE) are then measured for two energy threshold configurations (5 keV and 18 keV) and three doses ( approximately 3, 30 and 300 microGy), in order to obtain a complete estimation of the detector performances. In general, the CdTe sensor shows a clear superiority with a maximal DQE(0) of approximately 1, thanks to its high efficiency ( approximately 100%). The DQE of the Si sensor is more dependent on the radiation quality, due to the energy dependence of its efficiency its maximum is approximately 0.4 with respect to the softer radiation. Finally, we compare the XPAD3-S DQE with published curves of

  20. First-Principles Study of Electronic Structure of Type I Hybrid Carbon-Silicon Clathrates

    Science.gov (United States)

    Chan, Kwai S.; Peng, Xihong

    2016-08-01

    A new class of type I hybrid carbon-silicon clathrates has been designed using computational methods by substituting some of the Si atoms in the silicon clathrate framework with carbon atoms. In this work, the electronic structure of hybrid carbon-silicon clathrates with and without alkaline or alkaline-earth metal guest atoms has been computed within the density functional theory framework. The theoretical calculations indicate that a small number of carbon substitutions in the Si46 framework slightly reduces the density of states (DOS) near the band edge and narrows the bandgap of carbon-silicon clathrates. Weak hybridization of the conduction band occurs when alkaline metal (Li, Na, K) atoms are inserted into the structure, while strong hybridization of the conduction band occurs when alkaline-earth metal (Mg, Ca, Ba) atoms are inserted into the hybrid structure. Empty C y Si46- y clathrates within the composition range of 2 ≤ y ≤ 15 can be tuned to exhibit indirect bandgaps of 1.5 eV or less, and may be considered as potential electronic materials.

  1. Hybrid Corporate Performance Prediction Model Considering Technical Capability

    Directory of Open Access Journals (Sweden)

    Joonhyuck Lee

    2016-07-01

    Full Text Available Many studies have tried to predict corporate performance and stock prices to enhance investment profitability using qualitative approaches such as the Delphi method. However, developments in data processing technology and machine-learning algorithms have resulted in efforts to develop quantitative prediction models in various managerial subject areas. We propose a quantitative corporate performance prediction model that applies the support vector regression (SVR algorithm to solve the problem of the overfitting of training data and can be applied to regression problems. The proposed model optimizes the SVR training parameters based on the training data, using the genetic algorithm to achieve sustainable predictability in changeable markets and managerial environments. Technology-intensive companies represent an increasing share of the total economy. The performance and stock prices of these companies are affected by their financial standing and their technological capabilities. Therefore, we apply both financial indicators and technical indicators to establish the proposed prediction model. Here, we use time series data, including financial, patent, and corporate performance information of 44 electronic and IT companies. Then, we predict the performance of these companies as an empirical verification of the prediction performance of the proposed model.

  2. Mechanical and electrical performance of Roystonea regia/glass fibre reinforced epoxy hybrid composites

    Indian Academy of Sciences (India)

    Govardhan Goud; R N Rao

    2012-08-01

    The present paper investigates mechanical and electrical properties of Roystonea regia/glass fibre reinforced epoxy hybrid composites. Five varieties of hybrid composites have been prepared by varying the glass fibre loading. Roystonea regia (royal palm), a natural fibre was collected from the foliage of locally available royal palm tree through the process of water retting and mechanical extraction. Roystonea regia, -glass short fibres were used together as reinforcement in epoxy matrix to form hybrid composites. It has been observed that tensile, flexural, impact and hardness properties of hybrid composites considerably increased with increase in glass fibre loading. But electrical conductivity and dielectric constant values decreased with increase in glass fibre content in the hybrid composites at all frequencies. Scanning electron microscopy of fractured hybrid composites has been carried out to study the fibre matrix adhesion.

  3. Protonic/electronic hybrid oxide transistor gated by chitosan and its full-swing low voltage inverter applications

    Energy Technology Data Exchange (ETDEWEB)

    Chao, Jin Yu [Shanxi Province Key Laboratory High Gravity Chemical Engineering, North University of China, Taiyuan 030051 (China); Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Zhu, Li Qiang, E-mail: lqzhu@nimte.ac.cn; Xiao, Hui [Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Yuan, Zhi Guo, E-mail: ncityzg@163.com [Shanxi Province Key Laboratory High Gravity Chemical Engineering, North University of China, Taiyuan 030051 (China)

    2015-12-21

    Modulation of charge carrier density in condensed materials based on ionic/electronic interaction has attracted much attention. Here, protonic/electronic hybrid indium-zinc-oxide (IZO) transistors gated by chitosan based electrolyte were obtained. The chitosan-based electrolyte illustrates a high proton conductivity and an extremely strong proton gating behavior. The transistor illustrates good electrical performances at a low operating voltage of ∼1.0 V such as on/off ratio of ∼3 × 10{sup 7}, subthreshold swing of ∼65 mV/dec, threshold voltage of ∼0.3 V, and mobility of ∼7 cm{sup 2}/V s. Good positive gate bias stress stabilities are obtained. Furthermore, a low voltage driven resistor-loaded inverter was built by using an IZO transistor in series with a load resistor, exhibiting a linear relationship between the voltage gain and the supplied voltage. The inverter is also used for decreasing noises of input signals. The protonic/electronic hybrid IZO transistors have potential applications in biochemical sensors and portable electronics.

  4. Mode conversion and electron heating near the upper hybrid resonance frequency

    Energy Technology Data Exchange (ETDEWEB)

    Smith, B.L.; Okuda, H.; Abe, H.

    1983-11-01

    Mode conversion near the upper hybrid resonance frequency and electron heating are studied using a one-dimensional electromagnetic relativistic particle code. It is found that for a sufficiently small pump field E/sub 0/, E/sub 0//sup 2//4..pi..nT/sub e/ less than or equal to 0.01, electron heating is localized in a region near the electron cyclotron layer where the pump frequency is equal to the local electron gyrofrequency. For stronger pump fields, electron heating takes place more or less uniformly across a region between the upper hybrid resonance layer and the cyclotron layer. In addition, a significant fraction of electromagnetic energy associated with the pump is found to be reflected back into the vacuum from a region in the plasma near the upper hybrid resonance layer for both strong (E/sub 0//sup 2//4..pi..nT/sub e/ approx. = 1) and weak pumps (E/sub 0//sup 2//4..pi..nT/sub e/ << 1).

  5. Microwave exfoliated graphene oxide/TiO2 nanowire hybrid for high performance lithium ion battery

    Science.gov (United States)

    Ishtiaque Shuvo, Mohammad Arif; Rodriguez, Gerardo; Islam, Md Tariqul; Karim, Hasanul; Ramabadran, Navaneet; Noveron, Juan C.; Lin, Yirong

    2015-09-01

    Lithium ion battery (LIB) is a key solution to the demand of ever-improving, high energy density, clean-alternative energy systems. In LIB, graphite is the most commonly used anode material; however, lithium-ion intercalation in graphite is limited, hindering the battery charge rate and capacity. To date, one of the approaches in LIB performance improvement is by using porous carbon (PC) to replace graphite as anode material. PC's pore structure facilitates ion transport and has been proven to be an excellent anode material candidate in high power density LIBs. In addition, to overcome the limited lithium-ion intercalation obstacle, nanostructured anode assembly has been extensively studied to increase the lithium-ion diffusion rate. Among these approaches, high specific surface area metal oxide nanowires connecting nanostructured carbon materials accumulation have shown promising results for enhanced lithium-ion intercalation. Herein, we demonstrate a hydrothermal approach of growing TiO2 nanowires (TON) on microwave exfoliated graphene oxide (MEGO) to further improve LIB performance over PC. This MEGO-TON hybrid not only uses the high surface area of MEGO but also increases the specific surface area for electrode-electrolyte interaction. Therefore, this new nanowire/MEGO hybrid anode material enhances both the specific capacity and charge-discharge rate. Scanning electron microscopy and X-ray diffraction were used for materials characterization. Battery analyzer was used for measuring the electrical performance of the battery. The testing results have shown that MEGO-TON hybrid provides up to 80% increment of specific capacity compared to PC anode.

  6. Power electronics and electric machinery challenges and opportunities in electric and hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Adams, D.J.; Hsu, J.S.; Young, R.W. [Oak Ridge National Lab., TN (United States); Peng, F.Z. [Univ. of Tennessee, Knoxville, TN (United States)

    1997-06-01

    The development of power electronics and electric machinery presents significant challenges to the advancement of electric and hybrid vehicles. Electronic components and systems development for vehicle applications have progressed from the replacement of mechanical systems to the availability of features that can only be realized through interacting electronic controls and devices. Near-term applications of power electronics in vehicles will enable integrated powertrain controls, integrated chassis system controls, and navigation and communications systems. Future applications of optimized electric machinery will enable highly efficient and lightweight systems. This paper will explore the areas where research and development is required to ensure the continued development of power electronics and electric machines to meet the rigorous demands of automotive applications. Additionally, recent advances in automotive related power electronics and electric machinery at Oak Ridge National Laboratory will be explained. 3 refs., 5 figs.

  7. Hybrid aqueous capacitors with improved energy/power performance

    Directory of Open Access Journals (Sweden)

    Jakub Menzel

    2015-12-01

    Full Text Available This work reports on a high-voltage, hybrid capacitor involving two separate redox reactions. Aqueous solutions of Mg(NO32 and KI have been used for negative and positive electrode, respectively. Adjusting pH=2 for electrode (+ with KI solution and modifying Mg(NO32 solution to pH=9 for negative side play a crucial role for a stable long-term operation of capacitor at enhanced voltage. A benefit from such a construction is a pseudocapacitive contribution from hydrogen sorption reaction on the negative electrode and high iodine/iodide activity on the positive electrode, enhancing the energy with no remarkable impact on the power profile. Proposed solution allows a high voltage (1.8 V to be reached and thereby high power and energy performance (~20 W h/kg at 1 kW/kg to be obtained. High long-term stability has been confirmed by floating and galvanostatic tests.

  8. A review and design of power electronics converters for fuel cell hybrid system applications

    DEFF Research Database (Denmark)

    Zhang, Zhe; Pittini, Riccardo; Andersen, Michael A. E.

    2012-01-01

    This paper presents an overview of most promising power electronics topologies for a fuel cell hybrid power conversion system which can be utilized in many applications such as hybrid electrical vehicles (HEV), distributed generations (DG) and uninterruptible-power-supply (UPS) systems. Then......, a multiple-input power conversion system including a decoupled dual-input converter and a three-phase neutral-point-clamped (NPC) inverter is proposed. The system can operate in both stand-alone and grid-connected modes. Simulation and experimental results are provided to show the feasibility of the proposed...

  9. A camera for imaging hard x-rays from suprathermal electrons during lower hybrid current drive on PBX-M

    Energy Technology Data Exchange (ETDEWEB)

    von Goeler, S.; Kaita, R.; Bernabei, S.; Davis, W.; Fishman, H.; Gettelfinger, G.; Ignat, D.; Roney, P.; Stevens, J.; Stodiek, W. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Jones, S.; Paoletti, F. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center); Petravich, G. (Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics); Rimini,

    1993-05-01

    During lower hybrid current drive (LHCD), suprathermal electrons are generated that emit hard X-ray bremsstrahlung. A pinhole camera has been installed on the PBX-M tokamak that records 128 [times] 128 pixel images of the bremsstrahlung with a 3 ms time resolution. This camera has identified hollow radiation profiles on PBX-M, indicating off-axis current drive. The detector is a 9in. dia. intensifier. A detailed account of the construction of the Hard X-ray Camera, its operation, and its performance is given.

  10. Improving the photocatalytic performance of TiO2 via hybridizing with graphene

    Science.gov (United States)

    Divya, K. S.; Madhu, Athulya K.; Umadevi, T. U.; Suprabha, T.; Radhakrishnan Nair, P.; Suresh, Mathew

    2017-06-01

    In this paper an improvement in the photocatalytic performance of TiO{}2 was carried out via hybridizing with graphene. Graphene-TiO{}2 (GR-TiO{}2) nanocomposites with different weight addition ratios of graphene oxide (GO) have been prepared via a facile microwave irradiation of GO and tetrabutyl titanate in isopropyl alcohol. Raman spectroscopy (RS), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible spectroscopy (UV-vis), Fourier transform infrared spectra (FTIR), energy dispersive X-ray spectroscopy (EDX) and photoluminescence spectra (PL) are employed to determine the properties of the samples. Microwave irradiation can heat the reactant to a higher temperature in a short time, simultaneously GO is reduced to graphene and TiO{}2 nanoparticles grown on the surface of GR. GR-TiO{}2 nanocomposites synthesized via this approach have efficient electron conductivity in GR, resulting in a reduced electron-hole recombination rate. Among the synthesized nanocomposites, GT-8wt% exhibited the best photocatalytic activity toward photocatalytic degradation of MB. Our current work provides a new insight for the fabrication of GR-TiO{}2 nanocomposites within a short reaction time and also explains the mechanism of photocatalysis employing radical and hole scavengers.

  11. Flexible Organic/Inorganic Hybrid Field-Effect Transistors with High Performance and Operational Stability.

    Science.gov (United States)

    Dahiya, Abhishek S; Opoku, Charles; Poulin-Vittrant, Guylaine; Camara, Nicolas; Daumont, Christophe; Barbagiovanni, Eric G; Franzò, Giorgia; Mirabella, Salvo; Alquier, Daniel

    2017-01-11

    The production of high-quality semiconducting nanostructures with optimized electrical, optical, and electromechanical properties is important for the advancement of next-generation technologies. In this context, we herein report on highly obliquely aligned single-crystalline zinc oxide nanosheets (ZnO NSs) grown via the vapor-liquid-solid approach using r-plane (01-12) sapphire as the template surface. The high structural and optical quality of as-grown ZnO NSs has been confirmed using high-resolution transmission electron microscopy and temperature-dependent photoluminescence, respectively. To assess the potential of our NSs as effective building materials in high-performance flexible electronics, we fabricate organic (parylene C)/inorganic (ZnO NS) hybrid field-effect transistor (FET) devices on flexible substrates using room-temperature assembly processes. Extraction of key FET performance parameters suggests that as-grown ZnO NSs can successfully function as excellent n-type semiconducting modules. Such devices are found to consistently show very high on-state currents (Ion) > 40 μA, high field-effect mobility (μeff) > 200 cm(2)/(V s), exceptionally high on/off current modulation ratio (Ion/off) of around 10(9), steep subthreshold swing (s-s) low hysteresis, and negligible threshold voltage shifts with prolonged electrical stressing (up to 340 min). The present study delivers a concept of integrating high-quality ZnO NS as active semiconducting elements in flexible electronic circuits.

  12. Ternary Hybrid Material for High-Performance Lithium-Sulfur Battery.

    Science.gov (United States)

    Fan, Qi; Liu, Wen; Weng, Zhe; Sun, Yueming; Wang, Hailiang

    2015-10-14

    The rechargeable lithium-sulfur battery is a promising option for energy storage applications because of its low cost and high energy density. The electrochemical performance of the sulfur cathode, however, is substantially compromised because of fast capacity decay caused by polysulfide dissolution/shuttling and low specific capacity caused by the poor electrical conductivities of the active materials. Herein we demonstrate a novel strategy to address these two problems by designing and synthesizing a carbon nanotube (CNT)/NiFe2O4-S ternary hybrid material structure. In this unique material architecture, each component synergistically serves a specific purpose: The porous CNT network provides fast electron conduction paths and structural stability. The NiFe2O4 nanosheets afford strong binding sites for trapping polysulfide intermediates. The fine S nanoparticles well-distributed on the CNT/NiFe2O4 scaffold facilitate fast Li(+) storage and release for energy delivery. The hybrid material exhibits balanced high performance with respect to specific capacity, rate capability, and cycling stability with outstandingly high Coulombic efficiency. Reversible specific capacities of 1350 and 900 mAh g(-1) are achieved at rates of 0.1 and 1 C respectively, together with an unprecedented cycling stability of ∼0.009% capacity decay per cycle over more than 500 cycles.

  13. Investigation of the photovoltaic cell/ thermoelectric element hybrid system performance

    Science.gov (United States)

    Cotfas, D. T.; Cotfas, P. A.; Machidon, O. M.; Ciobanu, D.

    2016-06-01

    The PV/TEG hybrid system, consisting of the photovoltaic cells and thermoelectric element, is presented in the paper. The dependence of the PV/TEG hybrid system parameters on the illumination levels and the temperature is analysed. The maxim power values of the photovoltaic cell, of the thermoelectric element and of the PV/TEG system are calculated and a comparison between them is presented and analysed. An economic analysis is also presented.

  14. Systematic Design of High-performance Hybrid Feedback Algorithms

    Science.gov (United States)

    2015-06-24

    C8. A. Subbaraman and A.R. Teel, “A Krasovskii- LaSalle function based recurrence principle for a class of stochastic hybrid systems”, Proceedings...variety of results on this topic. Our results on stochastic discrete-time (difference) inclusions include an invariance principle [J1], converse...public release. 12 and an ensuing invariance /recurrence principle [C10], [C8]. We considered hybrid systems with both stochastic flows and stochastic

  15. Electronic and magnetic properties of modified silicene/graphene hybrid: Ab initio study

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, Suman; Jana, Debnarayan, E-mail: cujanad@yahoo.com

    2016-11-01

    Among other two-dimensional (2D) novel materials, graphene and silicene both have drawn intense research interest among the researchers because they possess some unique intriguing properties which can change the scenario of the current electronic industry. In this work we have studied the electronic and the magnetic properties of a new kind of materials which is the hybrid of these two materials. Density functional theory (DFT) has been employed to calculate the relevant electronic and magnetic properties of this hybrid material. The pristine structure is modified by substitutional doping or by creating vacancy (Y-X, where one Y atom (Si or C) has been replaced by one X atom (B, N, Al, P or void)). The calculations have revealed that void systems are unstable while Si-B and Si-N are most stable ones. It has been noticed that some of these doped structures are magnetic in nature having induced mid-gap states in the system. In particular, Si-void structure is unstable yet it possess the highest magnetic moment of the order of 4 μ{sub B} (μ{sub B} being the Bohr magneton). The estimated band gaps of modified silicene/graphene hybrid from spin polarized partial density of states (PDOS) vary between 1.43–2.38 eV and 1.58–2.50 eV for spin-up and spin-down channel respectively. The implication of midgap states has been critically analysed in the light of magnetic nature. This study may be useful to build hybrid spintronic devices with controllable gap for spin up and spin down states. - Graphical abstract: We have studied the electronic and magnetic properties of silicene/graphene hybrid by employing density functional theory (DFT). - Highlights: • Electronic and magnetic properties of two dimensional graphene/silicene hybrid have been explored. • There is no magnetism in the system for a single carbon atom vacancy. • A net magnetic moment of 4.0 Bohr magneton is observed for a single silicon atom vacancy. • Unpaired electrons introduce mid-gap states which

  16. Electron Cooling Performance at IMP Facility

    CERN Document Server

    Xiaodong, Yang

    2011-01-01

    The ion beam of 58Ni19+ with the energy of 6.39MeV/u was accumulated in the main ring of HIRFL-CSR with the help of electron cooling. The related angle between ion and electron beams in the horizontal and vertical planes was intentionally created by the steering coils in the cooling section after maximized the accumulated ion beam in the ring. The radial electron intensity distribution was changed by the ratio of potentials of grid electrode and anode of the electron gun, the different electron beam profiles were formed from solid to hollow in the experiments. In these conditions, the maximum accumulated ion beam intensity in the 10 seconds was measured, the lifetime of ion beam was measured, simultaneously the momentum spread of the ion beam varying with particle number was measured during the ion beam decay, furthermore, and the power coefficient was derived from these data. In additional, the momentum spread in the case of constant particle number was plotted with the angle and electron beam profile. The o...

  17. Hybridized Electromagnetic-Triboelectric Nanogenerator for a Self-Powered Electronic Watch.

    Science.gov (United States)

    Quan, Ting; Wang, Xue; Wang, Zhong Lin; Yang, Ya

    2015-12-22

    We report a hybridized nanogenerator including a triboelectric nanogenerator (TENG) and six electromagnetic generators (EMGs) that can effectively scavenge biomechanical energy for sustainably powering an electronic watch. Triggered by the natural motions of the wearer's wrist, a magnetic ball at the center in an acrylic box with coils on each side will collide with the walls, resulting in outputs from both the EMGs and the TENG. By using the hybridized nanogenerator to harvest the biomechanical energy, the electronic watch can be continuously powered under different motion types of the wearer's wrist, where the best approach is to charge a 100 μF capacitor in 39 s to maintain the continuous operation of the watch for 456 s. To increase the working time of the watch further, a homemade Li-ion battery has been utilized as the energy storage unit for realizing the continuous working of the watch for about 218 min by using the hybridized nanogenerator to charge the battery within 32 min. This work will provide the opportunities for developing a nanogenerator-based built-in power source for self-powered wearable electronics such as an electronic watch.

  18. Design and synthesis of MWNTs-TiO2 nanotube hybrid electrode and its supercapacitance performance

    Science.gov (United States)

    Gao, Zhonghui; Cui, Zhenduo; Zhu, Shengli; Liang, Yanqin; Li, Zhaoyang; Yang, Xianjin

    2015-06-01

    A new two-step method is successfully developed for the synthesis of MWNTs-TiO2 nanotube hybrid electrodes. The resulting (3-aminopropyl)triethoxysilane (APS) film was chemisorbed on the surface of TiO2 nanotubes. TiO2 nanotubes surface modified by 5, 10, and 20 mg ml-1 APS ethanol solution can determine the morphology of MWNTs-TiO2 nanotube electrodes. The morphology and surface composition were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) techniques. The zeta potential results confirm that MWNTs were deposited on APS-TiO2 nanotubes by the electrical attractive force. The electrochemical performances were evaluated by using cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge-discharge measurements. The MWNTs-TiO2 nanotube hybrid electrodes (5, 10, and 20 mg ml-1 APS) exhibited a high specific capacitance of 3.5, 4.4, and 3.4 mF cm-2 in 1 M H2SO4 aqueous solution at a charge-discharge current density of 0.1 mA cm-2, respectively. Cyclic voltammetric studies indicated that the electrode has excellent stability even after 1000 consecutive CV cycles. Moreover, the galvanostatic charge-discharge experiments conducted on the MWNTs-TiO2 nanotube hybrid electrodes (10 mg ml-1 APS) exhibited long-term cycle stability, retaining about 75% specific capacitance after 1000 cycles, which suggests that it has potential as an electrode material for high-performance electrochemical supercapacitors.

  19. Performance of Hybrid Corn in Different Environmental Conditions in the Region Of Sinop-MT

    Directory of Open Access Journals (Sweden)

    D. C. T. Souza

    2013-07-01

    Full Text Available Abstract: The aim of this study was to evaluate the agronomic performance of corn hybrids in environmental conditions favorable and unfavorable. For this, two experiments were conducted at Sinop / MT, being considered as favorable environmental conditions the use of fertilizer recommended for the crop at planting and coverage, and unfavorable conditions only recommended fertilization at planting. The experimental design was a randomized block with three replicates, with plots of 2 rows of 3 meters. The treatments were: double hybrid (Balu 761, single hybrids (AG 7088 and 30F90Y and triple hybrid (2B688. The characteristics evaluated were number of spikes, husked spikes weight, plant height and height of first spike. Regarding the number of ears, under favorable conditions, the hybrid double (Balu 761 and the triple hybrid (2B688 stood out against the simple hybrid. For the character number of spikes per plant, the husked spike weight in kg the triple hybrid 2B688 stood in relation to other unfavorable conditions. Considering the character plant height and first spike insertion, single hibrid 30F90Y, showed higher estimate in unfavorable conditions. In conclusion, the agronomic performance of types of hybrids varies in relation to environmental conditions and genotypes composition, and in this study the triple hybrid stood out in relation to others. Keywords: Zea mays, fertilization and breeding.

  20. A tapered undulator experiment at the ELBE far infrared hybrid-resonator oscillator free electron laser.

    Science.gov (United States)

    Asgekar, V; Lehnert, U; Michel, P

    2012-01-01

    A tapered undulator experiment was carried out at the ELBE far-infrared free electron laser (FEL). The oscillator FEL makes use of a hybrid optical resonator. The main motivation was to see whether the presence of a dispersive medium in the form of a waveguide in the resonator has any effect on the outcome. The FEL saturated power and the wavelength shifts have been measured as a function of both positive as well as negative undulator field amplitude tapering. In contrast to the typical high-gain FELs where positive tapering proves beneficial for the output power we observed an improvement of performance at negative taper. During the same experiments we studied the characteristics of the detuning curves. The width of the curves indicates a maximum small signal gain for zero taper while the output peak power increases with negative taper. The saturated power output, the detuning curve characteristics, and the wavelength shifts agrees with the theoretical predictions. Details of the experiment are presented.

  1. Modeling and design of a high-performance hybrid actuator

    Science.gov (United States)

    Aloufi, Badr; Behdinan, Kamran; Zu, Jean

    2016-12-01

    This paper presents the model and design of a novel hybrid piezoelectric actuator which provides high active and passive performances for smart structural systems. The actuator is composed of a pair of curved pre-stressed piezoelectric actuators, so-called commercially THUNDER actuators, installed opposite each other using two clamping mechanisms constructed of in-plane fixable hinges, grippers and solid links. A fully mathematical model is developed to describe the active and passive dynamics of the actuator and investigate the effects of its geometrical parameters on the dynamic stiffness, free displacement and blocked force properties. Among the literature that deals with piezoelectric actuators in which THUNDER elements are used as a source of electromechanical power, the proposed study is unique in that it presents a mathematical model that has the ability to predict the actuator characteristics and achieve other phenomena, such as resonances, mode shapes, phase shifts, dips, etc. For model validation, the measurements of the free dynamic response per unit voltage and passive acceleration transmissibility of a particular actuator design are used to check the accuracy of the results predicted by the model. The results reveal that there is a good agreement between the model and experiment. Another experiment is performed to teste the linearity of the actuator system by examining the variation of the output dynamic responses with varying forces and voltages at different frequencies. From the results, it can be concluded that the actuator acts approximately as a linear system at frequencies up to 1000 Hz. A parametric study is achieved here by applying the developed model to analyze the influence of the geometrical parameters of the fixable hinges on the active and passive actuator properties. The model predictions in the frequency range of 0-1000 Hz show that the hinge thickness, radius, and opening angle parameters have great effects on the frequency dynamic

  2. Enhanced electrochemical performance of carbon quantum dots-polyaniline hybrid

    Science.gov (United States)

    Zhao, Zhichao; Xie, Yibing

    2017-01-01

    Carbon quantum dots-polyaniline (CQDs-PANI) hybrid was developed as supercapacitor electorde material by incorporating CQDs into PANI. PANI nanowires were grown vertically on carbon fiber substrate to form an interconnected network structure. Meanwhile, CQDs were uniformly distributed in the interior and on the surface of well-established net-like PANI nanowires. High specific capacitance of 738.3 F g-1 at 1.0 A g-1 was obtained for CQDs-PANI compared to that of 432.5 F g-1 for pure PANI. The capacitance retention after 1000 cycles of CQDs-PANI and PANI is 78.0% and 68.0% at 5.0 A g-1, respectively. The high capacitance and reasonable cycle stability were ascribed to the incorporation of CQDs into PANI, which improved the conductivity and alleviated the volume change of the CQDs-PANI electrode during the charge/discharge process. In addition, a flexible solid-state CQDs-PANI supercapacitor was constructed using carbon paper as current collector and polyvinyl alcohol gel electrolyte, exhibiting the stable capacitive performance at planar and bending state. The specific capacitance, energy and power density were determined to be 169.2 mF cm-2, 33.8 μWh cm-2 and 0.3 mW cm-2 at a potential window of 1.2 V and a current density of 1.0 mA cm-2. CQDs-PANI presented the promising application in flexible energy-related device.

  3. Development of Capacitors for Power Electronics in Hybrid Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Balachandran, U. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-16

    The purpose of this CRADA is to develop a fabrication process to reduce the manufacturing cost for a very compact, high temperature, film-on-foil high energy-density PLZT (Pb-La-Zr- Ti-O) capacitor. Motivation for this CRADA is derived from the DOE’s Office of Vehicle Technologies (OVT) program, which seeks to advance technologies to improve vehicle fuel efficiency in the mid-term and facilitate the transition to electric drive vehicles over the longterm. The objective of Argonne’s work is to develop and characterize high-performance capacitors on base-metal foils. The PLZT film-on-foil prepared using a spin-coating technique

  4. Toward High-Performance Organic-Inorganic Hybrid Solar Cells: Bringing Conjugated Polymers and Inorganic Nanocrystals in Close Contact.

    Science.gov (United States)

    He, Ming; Qiu, Feng; Lin, Zhiqun

    2013-06-06

    Organic-inorganic hybrid solar cells composed of conjugated polymers (CPs) and inorganic nanocrystal (NC) semiconductors have garnered considerable attention as a potential alternative to traditional silicon solar cells due to the capacity of producing high-efficiency solar energy in a cost-effective manner. The combination of advantageous characteristics of CPs and NCs enables the construction of nanostructured high-performance, lightweight, flexible, large-area, and low-cost hybrid solar cells. However, it remains a grand challenge to control the film morphology and interfacial structure of such organic/inorganic semiconductor blends on the nanoscale. In this Perspective, we highlight the strategies of implementing close contact between CPs and NCs by tailoring the colloidal synthesis, the coordination reaction, and the chemical modification of CPs. As such, they offer promising opportunities for rationally controlling the phase separation between electron-donating CPs and electron-accepting NCs, increasing the interfacial areas between them, enhancing their electronic interaction, and thus substantially promoting the photovoltaic performance of the resulting organic-inorganic hybrid solar cells.

  5. Fabrication of alumina filled hybrid buckypaper composites and their enhancement of microwave absorbing performance

    Science.gov (United States)

    Miao, Hsin-Yuan; Liu, Jih-Hsin; Saravanan, L.

    2015-06-01

    Alumina (Al2O3)-filled multiwalled carbon nanotube buckypapers (BPs) with different Al2O3 loadings (5-50 wt%) were successfully synthesised. Structural and morphological analysis performed with x-ray diffraction and field-emission scanning electron microscopy, respectively, confirmed the presence of stable α-phase Al2O3 particles in the Al2O3-BP composites. The formation of flexible Al2O3-BP hybrid nanocomposites (5-15 wt%) was attributed to the strong interfacial polarisation and high conductivity; compared with pure Al2O3 and BP. The nanocomposites with optimised alumina loadings demonstrated enhanced microwave absorption (>90%) and a broader absorption bandwidth in the investigated high-frequency region.

  6. Tomography of the fast electron Bremsstrahlung emission during lower hybrid current drive on Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Peysson, Y.; Imbeaux, F. [Association Euratom-CEA, CEA/Cadarache, Dept. de Recherches sur la Fusion Controlee (DRFC), 13 - Saint-Paul-lez-Durance (France)

    1999-04-01

    A new tomography dedicated to detailed studies of the fast electron Bremsstrahlung emission in the hard X-ray (HXR) energy range between 20 and 200 keV during lower hybrid (LH) current drive experiments on the TORE SUPRA tokamak [Equipe TORE SUPRA, in Proceedings of the 15. Conference on Plasma Physics and Controlled Nuclear Fusion Research, Seville (International Atomic Energy Agency, Vienna, 1995), 1, AIEA-CN-60 / A1-5, p. 105] is presented. Radiation detection is performed by cadmium telluride(CdTe) semiconductors, which have most of the desirable features for a powerful diagnosing of magnetically confined hot plasmas - compact size, high X-ray stopping efficiency, fast timing characteristics, good energy resolution, no sensitivity to magnetic field, reasonable susceptibility to performance degradation from neutron/{gamma}-induced damages. This instrument is made of two independent cameras viewing a poloidal cross-section of the plasma, with respectively 21 and 38 detectors. A coarse spectrometry - 8 energy channels - is carried out for each chord, with an energy resolution of 20 keV. The spatial resolution in the core of the plasma is 4-5 cm, while the time sampling may be lowered down to of 2-4 ms. Powerful inversion techniques based on maximum entropy or regularization algorithms take fully advantage of the large number of line-integrated measurements for very robust estimates of the local HXR profiles as a function of time and photon energy. A detailed account of main characteristics and performances of the diagnostic is reported as well as preliminary results on LH current drive experiments. (authors)

  7. Hybrid quantum circuit with a superconducting qubit coupled to an electron spin ensemble

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, Yuimaru; Grezes, Cecile; Vion, Denis; Esteve, Daniel; Bertet, Patrice [Quantronics Group, SPEC (CNRS URA 2464), CEA-Saclay, 91191 Gif-sur-Yvette (France); Diniz, Igor; Auffeves, Alexia [Institut Neel, CNRS, BP 166, 38042 Grenoble (France); Isoya, Jun-ichi [Research Center for Knowledge Communities, University of Tsukuba, 305-8550 Tsukuba (Japan); Jacques, Vincent; Dreau, Anais; Roch, Jean-Francois [LPQM (CNRS, UMR 8537), Ecole Normale Superieure de Cachan, 94235 Cachan (France)

    2013-07-01

    We report the experimental realization of a hybrid quantum circuit combining a superconducting qubit and an ensemble of electronic spins. The qubit, of the transmon type, is coherently coupled to the spin ensemble consisting of nitrogen-vacancy (NV) centers in a diamond crystal via a frequency-tunable superconducting resonator acting as a quantum bus. Using this circuit, we prepare arbitrary superpositions of the qubit states that we store into collective excitations of the spin ensemble and retrieve back into the qubit. We also report a new method for detecting the magnetic resonance of electronic spins at low temperature with a qubit using the hybrid quantum circuit, as well as our recent progress on spin echo experiments.

  8. Theoretical investigation of the electronic structures and carrier transport of hybrid graphene and boron nitride nanostructure

    Directory of Open Access Journals (Sweden)

    Jia-Tao Sun

    2012-09-01

    graphene and hexagonal boron nitride (C-BN nanostructures receive much research interest due to the complementary electronic properties. Graphene is a zero-gap semiconductor, while hexagonal boron nitride (h-BN is a wide gap semiconductor. Here we studied the electronic structures and carrier transport of hybrid C-BN nanostructures by using first principles calculations and deformation potential theory. We have found that the physical quantities in these systems under study, band gap, effective mass, deformation potential, and carrier mobility, can be categorised into three different families depending on the width of graphene nanoribbon. This family behavior is similar to pristine armchair graphene nanoribbon, but with slight difference from the individual component. New opportunities of designing nanoelectric devices are discussed by utilizing the quantum confinement effect based on such kind of hybrid nanostructures.

  9. Student Performance in an Electronic Text Environment.

    Science.gov (United States)

    Friedman, Edward A.; And Others

    1989-01-01

    Describes a project conducted at Stevens Institute of Technology to develop and test the applicability of full-text electronic databases and full-text retrieval technology for use in undergraduate humanities education. The creation of a machine-readable database on Galileo is described, student reactions are discussed, and further work is…

  10. Hybrid simulation of whistler excitation by electron beams in two-dimensional non-periodic domains

    Energy Technology Data Exchange (ETDEWEB)

    Woodroffe, J.R., E-mail: woodrofj@erau.edu; Streltsov, A.V., E-mail: streltsa@erau.edu

    2014-11-01

    We present a two-dimensional hybrid fluid-PIC scheme for the simulation of whistler wave excitation by relativistic electron beams. This scheme includes a number of features which are novel to simulations of this type, including non-periodic boundary conditions and fresh particle injection. Results from our model suggest that non-periodicity of the simulation domain results in the development of fundamentally different wave characteristics than are observed in periodic domains.

  11. The superatom states of fullerenes and their hybridization into the nearly free electron bands of fullerites.

    Science.gov (United States)

    Zhao, Jin; Feng, Min; Yang, Jinlong; Petek, Hrvoje

    2009-04-28

    Motivated by the discovery of the superatom states of C60 molecules, we investigate the factors that influence their energy and wave function hybridization into nearly free electron bands in molecular solids. As the n = 3 solutions of the radial Schrodinger equation of the central attractive potential consisting of the short-range C atom core and the long-range collective screening potentials, respectively, located on the icosahedral C60 molecule shell and within its hollow core, superatom states are distinguished by their atom-like orbitals corresponding to different orbital angular momentum states (l = 0, 1, 2,...). Because they are less tightly bound than the pi orbitals, that is, the n = 2 states, which are often exploited in the intermolecular electron transport in aromatic organic molecule semiconductors, superatom orbitals hybridize more extensively among aggregated molecules to form bands with nearly free electron dispersion. The prospect of exploiting the strong intermolecular coupling to achieve metal-like conduction in applications such as molecular electronics may be attained by lowering the energy of superatom states from 3.5 eV for single chemisorbed C60 molecules to below the Fermi level; therefore, we study how the superatom state energies depend on factors such as their aggregation into 1D-3D solids, cage size, and exo- and endohedral doping by metal atoms. We find, indeed, that if the ionization potential of endohedral atom, such as copper, is sufficiently large, superatom states can form the conduction band in the middle of the gap between the HOMO and LUMO of the parent C60 molecule. Through a plane-wave density functional theory study, we provide insights for a new paradigm for intermolecular electronic interaction beyond the conventional one among the sp(n) hybridized orbitals of the organic molecular solids that could lead to design of novel molecular materials and quantum structures with extraordinary optical and electronic properties.

  12. Experimental Investigation for Tensile Performance of GFRP-Steel Hybridized Rebar

    Directory of Open Access Journals (Sweden)

    Dong-Woo Seo

    2016-01-01

    Full Text Available Tensile performance of the recently developed “FRP Hybrid Bar” at Korea Institute of Civil Engineering and Building Technology (KICT is experimentally evaluated by the authors. FRP Hybrid Bar is introduced to overcome the low elastic modulus of the existing GFRP bars to be used as a structural member in reinforced concrete structures. The concept of material hybridization is applied to increase elastic modulus of GFRP bars by using steel. This hybridized GFRP bar can be used in concrete structures as a flexural reinforcement with a sufficient level of elastic modulus. In order to verify the effect of material hybridization on tensile properties, tensile tests are conducted. The test results for both FRP Hybrid Bar and the existing GFRP bars are compared. The results indicate that the elastic modulus of FRP Hybrid Bar can be enhanced by up to approximately 250 percent by the material hybridization with a sufficient tensile strength. To ensure the long-term durability of FRP Hybrid Bar to corrosion resistance, the individual and combined effects of environmental conditions on FRP Hybrid Bar itself as well as on the interface between rebar and concrete are currently under investigation.

  13. Hybrid Adsorption-Membrane Biological Reactors for Improved Performance and Reliability of Perchlorate Removal Processes

    Science.gov (United States)

    2008-12-01

    carbon supply for the autotrophic perchlorate reducing bacteria. The membrane used in the reactor is a hollow-fiber microfiltration membrane made from...1 HYBRID ADSORPTION- MEMBRANE BIOLOGICAL REACTORS FOR IMPROVED PERFORMANCE AND RELIABILITY OF PERCHLORATE REMOVAL PROCESSES L.C. Schideman...Center Champaign, IL 61826, USA ABSTRACT This study introduces the novel HAMBgR process (Hybrid Adsorption Membrane Biological Reactor) and

  14. Photoemission study of ferrocenes: insights into the electronic structure of Si-based hybrid materials

    Energy Technology Data Exchange (ETDEWEB)

    Boccia, A; Marrani, A G; Stranges, S; Zanoni, R [Dipartimento di Chimica, Universita degli Studi di Roma ' La Sapienza' , piazzale Aldo Moro 5, I-00185 Rome (Italy); Alagia, M [ISMN-CNR, Sezione Romal, Piazzale Aldo Moro 5, I-00185 Roma, Italy and Laboratorio Nazionale TASC-CNR SS-14, Km 163.5, Basovizza, I-34012 Trieste (Italy); Iozzi, M F; Cossi, M [Dipartimento di Scienze dell' Ambiente e della Vita, Universita del Piemonte Orientale, via V. Bellini 25/G, I-15100 Alessandria (Italy)], E-mail: Andrea.Marrani@uniromal.it

    2008-03-15

    We present here the results of synchrotron radiation-excited UV-photoemission investigation and DFT calculations on vinylferrocene (VFC), a redox molecule suitable for applications in molecular electronics. A detailed assignment is discussed of the valence photoelectron spectra (UPS), which provides new data on the electronic structure and offers a partial re-interpretation of previous assignments on VFC based on theoretical and experimental evidences. Furthermore, the present results can allow for a meaningful comparison of photoemission results from the corresponding hybrid obtained by covalently attaching VFC to Si oriented surfaces.

  15. Quantum teleportation and entanglement swapping of electron spins in superconducting hybrid structures

    Energy Technology Data Exchange (ETDEWEB)

    Bubanja, Vladimir, E-mail: vladimir.bubanja@callaghaninnovation.govt.nz

    2015-06-15

    We present schemes for quantum teleportation and entanglement swapping of electronic spin states in hybrid superconductor–normal-metal systems. The proposed schemes employ subgap transport whereby the lowest order processes involve Cooper pair-electron and double Cooper-pair cotunneling in quantum teleportation and entanglement swapping protocols, respectively. The competition between elastic cotunneling and Cooper-pair splitting results in the success probability of 25% in both cases. Described implementations of these protocols are within reach of present-day experimental techniques.

  16. Mechanical performance of hybrid polyester composites reinforced Cloisite 30B and kenaf fibre

    Science.gov (United States)

    Bonnia, N. N.; Surip, S. N.; Ratim, S.; Mahat, M. M.

    2012-06-01

    Hybridization of rubber toughened polyester-kenaf nanocomposite was prepared by adding various percentage of kenaf fiber with 4% Cloisite 30B in unsaturated polyester resin. Composite were prepared by adding filler to modified polyester resin subsequently cross-linked using methyl ethyl ketone peroxide and the accelerator cobalt octanoate 1%. Three per hundred rubbers (phr) of liquid natural rubber (LNR) were added in producing this composite. This composite expected to be applied in the interior of passenger cars and truck cabins. This is a quality local product from a combination of good properties polyester and high performance natural fiber, kenaf that is suitable for many applications such as in automotive sector and construction sector. The mechanical and thermal properties of composite were characterized using Durometer Shore-D hardness test, Izod impact test, Scanning electron microscopy, thermogravimetry (TGA) and differential scanning calorimetry (DSC). Result shows that addition of LNR give good properties on impact, flexural and hardness compare to without LNR composite. DSC curve shows that all composition of composites is fully cured and good in thermal properties. Addition of higher percentage of kenaf will lead the composite to elastic behavior and decrease the toughened properties of the composite. Hybrid system composite showed the flexural properties within the flexural properties of kenaf - polyester and Cloisite 30B.

  17. Electrically engineered polymer-carbon hybrid heterojunction for high-performance printed transistors

    Science.gov (United States)

    Kim, Do Hwan; Kang, Gyu Won; Shin, Hyeon-Jin; Kim, Woo-Jae

    2014-10-01

    Molecularly hybridized materials composed of polymer semiconductors (PSCs) and single-walled carbon nanotubes (SWNTs) may provide a new platform to exploit an advantageous combination of semiconductors, which yields electrical properties that are not available in a single component system. In this talk, we demonstrate high-performance ink-jet printed hybrid transistors with an electrically engineered heterostructure by using specially designed PSCs and semiconducting SWNTs (sc-SWNTs) whose system achieved a high mobility of 0.23 cm2V-1s-1, no Von shift, a low off-current, and good bias-stability. We also revealed that binding energy between PSCs and sc-SWNT was strongly affected by side-chain length of PSCs, leading to the formation of homogeneous nanohybrid film. Eventually, understanding of electrostatic interactions in the heterostructure and experimental results suggest criteria for the design of nanohybrid heterostructures. Acknowledgement. This work was supported by a grant (Code No. 2011-0031628) from the Center for Advanced Soft Electronics under the Global Frontier Research Program of the Ministry of Science, ICT and Future Planning, Korea. The authors acknowledge Prof. Kilwon Cho for collaboration on the analysis of x-ray diffraction.

  18. Enhanced photovoltaic performance of polymer-filled nanoporous Si hybrid structures.

    Science.gov (United States)

    Gang, Minjae; Lee, Joo-Hyoung

    2017-02-15

    We propose a novel hybrid structure for improving the efficiency of crystalline silicon solar cells. By employing first-principles calculations, we demonstrate that ordered, nanoporous silicon (np-Si), when filled with polythiophene (PT) inside the pores, exhibits a substantially enhanced absorption coefficient compared to both np-Si and the bulk, which makes the np-Si/PT heterojunction a superior light absorbing material. In addition, the PT-filled porous structure forms a staggered gap, or type II, heterojunction at the interfaces, where the valence band maximum and conduction band minimum of the composite reside on PT and np-Si, respectively. Moreover, the pore-filling polymer brings about a highly dispersive valence band, which provides a major pathway for hole transport. These results suggest that such a hybrid structure, which may be easier to scale up than nanowire-based approaches, will efficiently dissociate photo-induced electron-hole pairs and reduce the amount of material for light absorption, thus leading to a cost-effective and high-performance solar cell.

  19. Graphene/MnO{sub 2} hybrid nanosheets as high performance electrode materials for supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Mondal, Anjon Kumar, E-mail: Anjon.K.Mondal@student.uts.edu.au [Centre for Clean Energy Technology, School of Chemistry and Forensic Science, University of Technology, Sydney, Broadway, Sydney, NSW 2007 (Australia); Wang, Bei; Su, Dawei; Wang, Ying; Chen, Shuangqiang [Centre for Clean Energy Technology, School of Chemistry and Forensic Science, University of Technology, Sydney, Broadway, Sydney, NSW 2007 (Australia); Zhang, Xiaogang [College of Materials Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing (China); Wang, Guoxiu, E-mail: Guoxiu.wang@uts.edu.au [Centre for Clean Energy Technology, School of Chemistry and Forensic Science, University of Technology, Sydney, Broadway, Sydney, NSW 2007 (Australia)

    2014-01-15

    Graphene/MnO{sub 2} hybrid nanosheets were prepared by incorporating graphene and MnO{sub 2} nanosheets in ethylene glycol. Scanning electron microscopy and transmission electron microscopy analyses confirmed nanosheet morphology of the hybrid materials. Graphene/MnO{sub 2} hybrid nanosheets with different ratios were investigated as electrode materials for supercapacitors by cyclic voltammetry (CV) and galvanostatic charge–discharge in 1 M Na{sub 2}SO{sub 4} electrolyte. We found that the graphene/MnO{sub 2} hybrid nanosheets with a weight ratio of 1:4 (graphene:MnO{sub 2}) delivered the highest specific capacitance of 320 F g{sup −1}. Graphene/MnO{sub 2} hybrid nanosheets also exhibited good capacitance retention on 2000 cycles. - Highlights: • Graphene/MnO{sub 2} hybrid nanosheets with different ratios were fabricated. • The specific capacitance is strongly dependent on graphene/MnO{sub 2} ratios. • The graphene/MnO{sub 2} hybrid electrode (1:4) exhibited high specific capacitance. • The electrode retained 84% of the initial specific capacitance after 2000 cycles.

  20. Screened Hybrid and DFT + U Studies of the Structural, Electronic, and Optical Properties of U3O8

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Xiaodong; Martin, Richard L.; Scuseria, Gustavo E.; Rudin, Sven P.; Batista, Enrique R.; Burrell, Anthony K.

    2012-11-26

    A systematic comparison of the structures and electronic and optical properties of U3O8 in the c2mm, P¯62m, and P21/m structures (the α, β, and γ phases, respectively) is performed using density functional theory + U (PBE + U) and the Heyd–Scuseria–Ernzerhof screened hybrid functional (HSE). The relationship between the semiconducting C2mm phase of U3O8 and the high temperature, metallic P¯62m phase is explored in more detail. Our calculated results show that the HSE functional gives a better description of the electronic and optical properties when compared with available experimental data for the α and β phases, but neither approach does particularly well for the high pressure γ phase.

  1. Screened hybrid and DFT + U studies of the structural, electronic, and optical properties of U3O8

    Science.gov (United States)

    Wen, Xiao-Dong; Martin, Richard L.; Scuseria, Gustavo E.; Rudin, Sven P.; Batista, Enrique R.; Burrell, Anthony K.

    2013-01-01

    A systematic comparison of the structures and electronic and optical properties of U3O8 in the c2mm, P\\bar {6}2 m, and P21/m structures (the α, β, and γ phases, respectively) is performed using density functional theory + U (PBE + U) and the Heyd-Scuseria-Ernzerhof screened hybrid functional (HSE). The relationship between the semiconducting C2mm phase of U3O8 and the high temperature, metallic P\\bar {6}2 m phase is explored in more detail. Our calculated results show that the HSE functional gives a better description of the electronic and optical properties when compared with available experimental data for the α and β phases, but neither approach does particularly well for the high pressure γ phase.

  2. A hybrid density functional study on the electron and hole trap states in anatase titanium dioxide.

    Science.gov (United States)

    Yamamoto, Takenori; Ohno, Takahisa

    2012-01-14

    We present a theoretical study on electron and hole trap states in the bulk and (001) surface of anatase titanium dioxide using screened hybrid density functional calculations. In both the bulk and surface, calculations suggest that the neutral and ionized oxygen vacancies are possible electron traps. The doubly ionized oxygen vacancy is the most stable in the bulk, and is a candidate for a shallow donor in colorless anatase crystals. The hole trap states are localized at oxygen anions in both the bulk and surface. The self-trapped electron centered at a titanium cation cannot be produced in the bulk, but can be formed at the surface. The electron trap level at the surface oxygen vacancy is consistent with observations by photoelectron spectroscopy. The optical absorptions and luminescence in UV-irradiated anatase nanoparticles are found to come from the surface self-trapped hole and the surface oxygen vacancy.

  3. High Performance Builder Spotlight: Wathen Castanos Hybrid Homes

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-01-01

    Wathen Castanos Hybrid Homes of Fresno, CA, has worked with Building America team member IBACOS to apply building science to production homes. Even without solar panels, the company’s Jordan model exceeds California’s building efficiency standard by 36%.

  4. The nature of excess electrons in anatase and rutile from hybrid DFT and RPA.

    Science.gov (United States)

    Spreafico, Clelia; VandeVondele, Joost

    2014-12-21

    The behavior of excess electrons in undoped and defect free bulk anatase and rutile TiO2 has been investigated by state-of-the-art electronic structure methods including hybrid density functional theory (DFT) and the random phase approximation (RPA). Consistent with experiment, charge trapping and polaron formation is observed in both anatase and rutile. The difference in the anisotropic shape of the polarons is characterized, confirming for anatase the large polaron picture. For anatase, where polaron formation energies are small, charge trapping is observed also with standard hybrid functionals, provided the simulation cell is sufficiently large (864 atoms) to accommodate the lattice relaxation. Even though hybrid orbitals are required as a starting point for RPA in this system, the obtained polaron formation energies are relatively insensitive to the amount of Hartree-Fock exchange employed. The difference in trapping energy between rutile and anatase can be obtained accurately with both hybrid functionals and RPA. Computed activation energies for polaron hopping and delocalization clearly show that anatase and rutile might have different charge transport mechanisms. In rutile, only hopping is likely, whereas in anatase hopping and delocalization are competing. Delocalization will result in conduction-band-like and thus enhanced transport. Anisotropic conduction, in agreement with experimental data, is observed, and results from the tendency to delocalize in the [001] direction in rutile and the (001) plane in anatase. For future work, our calculations serve as a benchmark and suggest RPA on top on hybrid orbitals (PBE0 with 30% Hartree-Fock exchange), as a suitable method to study the rich chemistry and physics of TiO2.

  5. Lifecycle performance. Special issue on management and maintenance, hybrid ventilation concepts, installation-low buildings; Lifecycle performance. Themanummer over beheer en onderhoud, hybride ventilatieconcepten, installatie-arme gebouwen

    Energy Technology Data Exchange (ETDEWEB)

    Thierauf, I. [Universiteit Utrecht, Utrecht (Netherlands); Kurvers, S.R.; Van den Ham, E.R.; Leijten, J.L. [Sectie Climate Design and Sustainability, Afdeling Architectural Engineering and Technology, Faculteit Bouwkunde, Technische Universiteit Delft TUD, Delft (Netherlands); Juricic, S. [Ecole National des Travaux Publics de l' Etat, Lyon (France); Jacobs, P. [Afdeling Energy and Comfort Systems, TNO, Delft (Netherlands); Versteeg, H. [LBP Sight, Nieuwegein (Netherlands); Van Loon, P.P.M. [Stichting Scholen van Morgen, Rotterdam (Netherlands); Hoek, H.C.; Van Eeden, H.; Nibbelink, J. [Collectief C-on, Haarlem (Netherlands); Veerman, J.; Maassen, W.H. [Royal Haskoning DHV, Nijmegen (Netherlands); Derksen, A.H.P. [ISSO, Rotterdam (Netherlands); Morren, K. [Universiteit Twente, Enschede (Netherlands)

    2012-12-15

    In 9 articles various aspects regarding the title topic are discussed: energy efficiency and user comfort, ventilation in new houses with balanced ventilation, the revised assessment for ventilation performance, air quality in school buildings, buildings with only a few installations, hybrid ventilation, the management and maintenance process, and future performance requirements [Dutch] In 9 artikelen wordt aandacht besteed aan diverse aspecten m.b.t. het titelonderwerp: energie-efficientie en gebruikerscomfort, ventilatie in nieuwbouwwoningen met balansventilatie, de herziene beoordelingsrichtlijn ventilatie prestatie, luchtkwaliteit in schoolgebouwen, installatie-arme gebouwen, hybride ventilatie, het beheer- en onderhoudsproces, en de toekomstige prestatie-eisen.

  6. Heat transfer performance characteristics of hybrid nanofluids as coolant in louvered fin automotive radiator

    Science.gov (United States)

    Sahoo, Rashmi R.; Sarkar, Jahar

    2016-12-01

    Present study deals with the enhancement of convective heat transfer performance of EG brine based various hybrid nanofluids i.e. Ag, Cu, SiC, CuO and TiO2 in 0-1% volume fraction of Al2O3 nanofluid, as coolants for louvered fin automobile radiator. The effects of nanoparticles combination and operating parameters on thermo physical properties, heat transfer, effectiveness, pumping power and performance index of hybrid nanofluids have been evaluated. Comparison of studied hybrid nanofluids based on radiator size and pumping power has been made as well. Among all studied hybrid nanofluids, 1% Ag hybrid nanofluid (0.5% Ag and 0.5% Al2O3) yields highest effectiveness and heat transfer rate as well as pumping power. However, SiC + Al2O3 dispersed hybrid nanofluid yields maximum performance index and hence this can be recommended for best coolant. For the same radiator size and heat transfer rate, pumping power increases by using Ag hybrid nanofluids leading to increase in engine thermal efficiency and hence reduction in engine fuel consumption. For same coolant flow rate and heat transfer rate, the radiator size reduces and pumping power increases by using Ag hybrid nanofluids leading to reduction in radiator size, weight and cost.

  7. Heat transfer performance characteristics of hybrid nanofluids as coolant in louvered fin automotive radiator

    Science.gov (United States)

    Sahoo, Rashmi R.; Sarkar, Jahar

    2017-06-01

    Present study deals with the enhancement of convective heat transfer performance of EG brine based various hybrid nanofluids i.e. Ag, Cu, SiC, CuO and TiO2 in 0-1% volume fraction of Al2O3 nanofluid, as coolants for louvered fin automobile radiator. The effects of nanoparticles combination and operating parameters on thermo physical properties, heat transfer, effectiveness, pumping power and performance index of hybrid nanofluids have been evaluated. Comparison of studied hybrid nanofluids based on radiator size and pumping power has been made as well. Among all studied hybrid nanofluids, 1% Ag hybrid nanofluid (0.5% Ag and 0.5% Al2O3) yields highest effectiveness and heat transfer rate as well as pumping power. However, SiC + Al2O3 dispersed hybrid nanofluid yields maximum performance index and hence this can be recommended for best coolant. For the same radiator size and heat transfer rate, pumping power increases by using Ag hybrid nanofluids leading to increase in engine thermal efficiency and hence reduction in engine fuel consumption. For same coolant flow rate and heat transfer rate, the radiator size reduces and pumping power increases by using Ag hybrid nanofluids leading to reduction in radiator size, weight and cost.

  8. Improving the performance of a hybrid electric vehicle by utilization regenerative braking energy of vehicle

    Directory of Open Access Journals (Sweden)

    Mohamed Mourad

    2011-01-01

    Full Text Available Environmentally friendly vehicles with range and performance capabilities surpassing those of conventional ones require a careful balance among competing goals for fuel efficiency, performance and emissions. It can be recuperated the energy of deceleration case of the vehicle to reuse it to recharge the storage energy of hybrid electric vehicle and increase the state of charge of batteries under the new conditions of vehicle operating in braking phase. Hybrid electric vehicle has energy storage which allows decreasing required peak value of power from prime mover, which is the internal combustion engine. The paper investigates the relationships between the driving cycle phases and the recuperation energy to the batteries system of hybrid electric vehicle. This work describes also a methodology for integrating this type of hybrid electric vehicle in a simulation program. A design optimization framework is then used to find the best position that we can utilize the recuperation energy to recharge the storage batteries of hybrid electric vehicle.

  9. The analysis of single-electron orbits in a free electron laser based upon a rectangular hybrid wiggler

    Science.gov (United States)

    Kordbacheh, A.; Ghahremaninezhad, Roghayeh; Maraghechi, B.

    2012-09-01

    A three-dimensional analysis of a novel free-electron laser (FEL) based upon a rectangular hybrid wiggler (RHW) is presented. This RHW is designed in a configuration composed of rectangular rings with alternating ferrite and dielectric spacers immersed in a solenoidal magnetic field. An analytic model of RHW is introduced by solution of Laplace's equation for the magnetostatic fields under the appropriate boundary conditions. The single-electron orbits in combined RHW and axial guide magnetic fields are studied when only the first and the third spatial harmonic components of the RHW field are taken into account and the higher order terms are ignored. The results indicate that the third spatial harmonic leads to group III orbits with a strong negative mass regime particularly in large solenoidal magnetic fields. RHW is found to be a promising candidate with favorable characteristics to be used in microwave FEL.

  10. Performance of the ELBE BPM Electronics

    CERN Document Server

    Evtushenko, P

    2003-01-01

    The ELBE radiation source is based on a superconducting linac. Initially it was designed to be used in CW mode with repetition rates either 13 MHz either 260 MHz. Later it was decided to operate the accelerator with reduced repetition rates for diagnostic reasons and for certain users. Now it is possible to operate at repetition rate 13/n MHz, where n can be 2, 4, 8, 16, 32, 64, and 128. It is required that the BPM system supports any of these operation modes. A core element of the BPM electronics is a logarithmic amplifier AD8313 made by Analog Devices Inc. The logarithmic amplifier is a direct RF to DC converter rated up to 2.5 GHz. Initial design of the BPM electronic was sophisticated only for CW operation with repetition rate more than 10 MHz, since bandwidth of the AD8313 is about of 10 MHz. Additionally a sample and hold amplifier is built in to provide enough time for an ADC to make measurements. The sample and hold amplifier is synchronized with a micropulse frequency. In the paper we present results...

  11. Direct switching control of DC-DC power electronic converters using hybrid system theory

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, J.; Lin, F. [Wayne State Univ., Detroit, MI (United States). Dept. of Electrical and Computer Engineering; Wang, C. [Wayne State Univ., Detroit, MI (United States). Dept. of Electrical and Computer Engineering; Wayne State Univ., Detroit, MI (United States). Div. of Engineering Technology

    2010-07-01

    A direct switching control (DSC) scheme for power electronics converters was described. The system was designed for use in both traditional and renewable energy applications as well as in electric drive vehicles. The proposed control scheme was based on a detailed hybrid system converter model that used model predictive control (MPC), piecewise affine (PWA) approximations and constrained optimal control methods. A DC-DC converter was modelled as a hybrid machine. Switching among different modes of the DC-DC converter were modelled as discrete events controlled by the hybrid controller. The modelling scheme was applied to a Buck converter. The DSC was used to control the switch of the power converter based on a hybrid machine model. Results of the study showed that the method can be used to regulate output voltage and inductor currents. The method also provides fast transient responses and effectively regulates both currents and voltage. The controller can be used to provide immediate responses to dynamic disturbances and output voltage fluctuations. 23 refs., 7 figs.

  12. Evaluation of Performance and Opportunities for Improvements in Automotive Power Electronics Systems: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Gilberto; Bennion, Kevin; King, Charles; Narumanchi, Sreekant

    2016-06-14

    Thermal management strategies for automotive power electronic systems have evolved over time to reduce system cost and to improve reliability and thermal performance. In this study, we characterized the power electronic thermal management systems of two electric-drive vehicles--the 2012 Nissan LEAF and 2014 Honda Accord Hybrid. Tests were conducted to measure the insulated-gate bipolar transistor-to-coolant thermal resistances for both steady-state and transient conditions at various coolant flow rates. Water-ethylene glycol at a temperature of 65 degrees C was used as the coolant for these experiments. Computational fluid dynamics and finite element analysis models of the vehicle's power electronics thermal management system were then created and validated using experimentally obtained results. Results indicate that the Accord module provides lower steady-state thermal resistance as compared with the LEAF module. However, the LEAF design may provide improved performance in transient conditions and may have cost benefits.

  13. Fuel Economy and Performance of Mild Hybrids with Ultracapacitors: Simulations and Vehicle Test Results (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Gonder, J.; Pesaran, A.; Lustbader, J.; Tataria, H.

    2009-06-01

    NREL worked with GM and demonstrated equivalent performance in the Saturn Vue Belt Alternator Starter (BAS) hybrid vehicle whether running with its stock batteries or a retrofit ultracapacitor system.

  14. Hybrid Scenario Based Performance Analysis of DSDV and DSSR

    CERN Document Server

    Majumder, Koushik; 10.5121/ijcsit.2010.2305

    2010-01-01

    The area of mobile ad hoc networking has received considerable attention of the research community in recent years. These networks have gained immense popularity primarily due to their infrastructure-less mode of operation which makes them a suitable candidate for deployment in emergency scenarios like relief operation, battlefield etc., where either the pre-existing infrastructure is totally damaged or it is not possible to establish a new infrastructure quickly. However, MANETs are constrained due to the limited transmission range of the mobile nodes which reduces the total coverage area. Sometimes the infrastructure-less ad hoc network may be combined with a fixed network to form a hybrid network which can cover a wider area with the advantage of having less fixed infrastructure. In such a combined network, for transferring data, we need base stations which act as gateways between the wired and wireless domains. Due to the hybrid nature of these networks, routing is considered a challenging task. Several r...

  15. A Novel Homogenous Hybridization Scheme for Performance Improvement of Support Vector Machines Regression in Reservoir Characterization

    Directory of Open Access Journals (Sweden)

    Kabiru O. Akande

    2016-01-01

    Full Text Available Hybrid computational intelligence is defined as a combination of multiple intelligent algorithms such that the resulting model has superior performance to the individual algorithms. Therefore, the importance of fusing two or more intelligent algorithms to achieve better performance cannot be overemphasized. In this work, a novel homogenous hybridization scheme is proposed for the improvement of the generalization and predictive ability of support vector machines regression (SVR. The proposed and developed hybrid SVR (HSVR works by considering the initial SVR prediction as a feature extraction process and then employs the SVR output, which is the extracted feature, as its sole descriptor. The developed hybrid model is applied to the prediction of reservoir permeability and the predicted permeability is compared to core permeability which is regarded as standard in petroleum industry. The results show that the proposed hybrid scheme (HSVR performed better than the existing SVR in both generalization and prediction ability. The outcome of this research will assist petroleum engineers to effectively predict permeability of carbonate reservoirs with higher degree of accuracy and will invariably lead to better reservoir. Furthermore, the encouraging performance of this hybrid will serve as impetus for further exploring homogenous hybrid system.

  16. Hybrid density functional study of the structural, bonding, and electronic properties of bismuth vanadate

    Science.gov (United States)

    Kweon, Kyoung E.; Hwang, Gyeong S.

    2012-10-01

    The structure and property prediction of metal oxides can significantly be improved by incorporating exact Hartree-Fock (HF) exchange into density functional theory (DFT), which is the so-called hybrid DFT. We explored the impact of HF exchange inclusion on the predicted structural, bonding, and electronic properties of bismuth vanadate (BiVO4), with particular attention to the difference between its monoclinic and tetragonal scheelite phases. The applied exchange-correlation (xc) functionals include the gradient corrected Perdew-Burke-Ernzerhof (PBE) and the PBE-HF hybrid functionals with HF exchange amounts of 10%, 25%, and 50%. We find that the PBE-HF25% yields a monoclinic structure in very close agreement with the experimentally determined structure, while the PBE-HF50% tends to overestimate the monoclinic distortion and the PBE/PBE-HF10% can hardly identify a distinct monoclinic configuration at ambient conditions. Electronic structure analysis reveals that the increasing monoclinic distortion with the amount of HF exchange is related to the enhancement of hybridization between Bi 6s-O 2p antibonding states and unoccupied Bi 6p states. The bonding mechanisms and band structures of the monoclinic and tetragonal phases of BiVO4 were also investigated, and we discuss how the predictions are sensitive to the xc functional choice.

  17. THE CONCEPT OF HYBRID MANUFACTURING FOR HIGH PERFORMANCE PARTS#

    Directory of Open Access Journals (Sweden)

    K. Boivie

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The development of additive manufacturing technology (AMT for metallic materials has reached a level where the processes are capable of producing complex geometries with industrial grade material properties. However, AMT is still hardly competitive with conventional (subtractive machining with regard to production speed, accuracy, and surface quality. To address these limitations, AMT can be combined with subtractive manufacturing technology into a hybrid manufacturing system. This paper introduces the concept of hybrid manufacturing with examples from ongoing industrial case studies, and describes the requirements for the future development of an integrated hybrid manufacturing system.

    AFRIKAANSE OPSOMMING: Die ontwikkeling van byvoegende vervaardigingstegnologie vir metaal het die peil bereik waar prosesse in staat is om komplekse meetkundes te vervaardig met nywerheidsgraad materiale. Die tegnologie ondervind egter strawwe mededinging vanaf konvensionele masjinering ten opsigte van produksienetheid, akkuraatheid en oppervlakte-afwerking. Die twee mededingende metodes kan egter tesame gebruik word as ’n bastersisteem soos getoon deur voortgaande industriële gevallestudies.

  18. Performance of hybrid ball bearings in oil and jet fuel

    Science.gov (United States)

    Schrader, Stephen M.; Pfaffenberger, Eugene E.

    1992-07-01

    A 308-size hybrid ball bearing, with ceramic balls and steel rings, was tested using a diester oil and gas turbine fuel as lubricants at several speeds and loads. Heat generation data from this test work was then correlated with the heat generation model from a widely used computer code. The ability of this hybrid split inner ring bearing design to endure thrust reversals, which are expected in many turbine applications, was demonstrated. Finally, the bearing was successfully endurance tested in JP-10 fuel for 25 hours at 7560 N axial load and 36,000 rpm. This work has successfully demonstrated the technology necessary to use fuel-lubricated hybrid bearings in limited-life gas turbine engine applications such as missiles, drones, and other unmanned air vehicles (UAVs). In addition, it has provided guidance for use in designing such bearing systems. As a result, the benefits of removing the conventional oil lubricant system, i.e., design simplification and reduced maintenance, can be realized.

  19. Ensilage performance of sorghum hybrids varying in extractable sugars

    Energy Technology Data Exchange (ETDEWEB)

    Philipp, Dirk; Moore, Kenneth J. [Iowa State University, Ames (United States); Pedersen, Jeffrey F.; Mitchell, Robert B. [University of Nebraska, Lincoln, NE (United States). USDA-ARS, Department of Agronomy; Grant, Richard J. [William H. Miner Agricultural Research Institute, Chazy, NY (United States); Redfearn, Daren D. [Oklahoma State University, Stillwater, OK (United States). Department of Plant and Soil Sciences

    2007-07-15

    Renewable feedstock resources require novel storage technologies to optimize industrial use. Solid state fermentation of biomass feedstock may provide organic chemicals and fibers while reducing the risk of current dry-storage procedures. Here, we compare the chemical composition and fermentation of six sorghum hybrids (Sorghum bicolor L. Moench) following 1, 7, and 21 days of storage. Ensilage of 7 days resulted in a pH of 3.8 and declined further to 3.75 at day 21. Lactate increased during ensilage from 2.0 to 3.9 g 100 g{sup -1}. Acetic acid increased between 1 and 7 days of ensiling but did not change until the end of the ensiling period. Total organic acids averaged 2.5 g 100 g{sup -1} after day 1 and increased to 4.2 and 4.7 g '100 g{sup -1} after days 7 and 21, respectively. Neutral detergent fiber ranged from 38 to 50 g 100 g{sup -1} among hybrids and total non-structural carbohydrates varied from 18 to 32 g 100 g{sup -1}. Hemicellulose and cellulose ranged from 13 to 19 g 100 g{sup -1} and 20 and 28 g 100 g{sup -1}, respectively. Genotypic variation in sorghum may offer designing dual-purpose hybrids for production of biomass and economically valuable byproducts. (author)

  20. Optimum Performance-Based Seismic Design Using a Hybrid Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    S. Talatahari

    2014-01-01

    Full Text Available A hybrid optimization method is presented to optimum seismic design of steel frames considering four performance levels. These performance levels are considered to determine the optimum design of structures to reduce the structural cost. A pushover analysis of steel building frameworks subject to equivalent-static earthquake loading is utilized. The algorithm is based on the concepts of the charged system search in which each agent is affected by local and global best positions stored in the charged memory considering the governing laws of electrical physics. Comparison of the results of the hybrid algorithm with those of other metaheuristic algorithms shows the efficiency of the hybrid algorithm.

  1. A theoretical prediction of super high-performance thermoelectric materials based on MoS2/WS2 hybrid nanoribbons.

    Science.gov (United States)

    Zhang, Zhongwei; Xie, Yuee; Peng, Qing; Chen, Yuanping

    2016-02-17

    Modern society is hungry for electrical power. To improve the efficiency of energy harvesting from heat, extensive efforts seek high-performance thermoelectric materials that possess large differences between electronic and thermal conductance. Here we report a super high-performance material of consisting of MoS2/WS2 hybrid nanoribbons discovered from a theoretical investigation using nonequilibrium Green's function methods combined with first-principles calculations and molecular dynamics simulations. The hybrid nanoribbons show higher efficiency of energy conversion than the MoS2 and WS2 nanoribbons due to the fact that the MoS2/WS2 interface reduces lattice thermal conductivity more than the electron transport. By tuning the number of the MoS2/WS2 interfaces, a figure of merit ZT as high as 5.5 is achieved at a temperature of 600 K. Our results imply that the MoS2/WS2 hybrid nanoribbons have promising applications in thermal energy harvesting.

  2. Electronic structures of one-dimensional metal-molecule hybrid chains studied using scanning tunneling microscopy and density functional theory.

    Science.gov (United States)

    Chung, Kyung-Hoon; Koo, Bon-Gil; Kim, Howon; Yoon, Jong Keon; Kim, Ji-Hoon; Kwon, Young-Kyun; Kahng, Se-Jong

    2012-05-28

    The electronic structures of self-assembled hybrid chains comprising Ag atoms and organic molecules were studied using scanning tunneling microscopy (STM) and spectroscopy (STS) in parallel with density functional theory (DFT). Hybrid chains were prepared by catalytic breaking of Br-C bonds in 4,4″-dibromo-p-terphenyl molecules, followed by spontaneous formation of Ag-C bonds on Ag(111). An atomic model was proposed for the observed hybrid chain structures. Four electronic states were resolved using STS measurements, and strong energy dependence was observed in STM images. These results were explained using first-principles calculations based on DFT.

  3. Femtosecond spectroscopic studies of photoinduced electron transfer in MDMO-PPV:ZnO hybrid bulk heterojunctions

    Energy Technology Data Exchange (ETDEWEB)

    Cecchetto, E.; De Cola, L. [Institute of Physics, University of Muenster, Mendelstrasse 7, 48149 Muenster (Germany); Slooff, H. [ECN Solar Energy, P.O. Box 1, 1755 ZG Petten (Netherlands); Zhang, H. [Van ' t Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 129, 1018 WS Amsterdam (Netherlands)

    2007-01-15

    The photophysics of charge carriers (polaron) in MDMO-PPV:ZnO hybrid bulk heterojunction is studied at 80 K by femtosecond transient absorption spectroscopy. A short-lived positive polaron is observed in the blend phase in MDMO-PPV:ZnO blend films with a weight ratio of 1:1 and 1:2. Further increase of ZnO weight ratio results in a significant quenching of the polaron absorption. The results are discussed in the concept that both pristine polymer and MDMO-PPV:ZnO blend phases coexist in the blend films. It is concluded that a polaron is photogenerated within the excitation laser pulse (<100 fs) and electron transfer efficiency is highest in blend films 1:1 and 1:2. Lack of the interfacial area and faster back electron transfer process are discussed to be responsible for the quenching of the electron transfer efficiency in blend film 1:3.

  4. A linear dispersion relation for the hybrid kinetic-ion/fluid-electron model of plasma physics

    CERN Document Server

    Told, Daniel; Astfalk, Patrick; Jenko, Frank

    2016-01-01

    A dispersion relation for a commonly used hybrid model of plasma physics is developed, which combines fully kinetic ions and a massless-electron fluid description. Although this model and variations of it have been used to describe plasma phenomena for about 40 years, to date there exists no general dispersion relation to describe the linear wave physics contained in the model. Previous efforts along these lines are extended here to retain arbitrary wave propagation angles, temperature anisotropy effects, as well as additional terms in the generalized Ohm's law which determines the electric field. A numerical solver for the dispersion relation is developed, and linear wave physics is benchmarked against solutions of a full Vlasov-Maxwell dispersion relation solver. This work opens the door to a more accurate interpretation of existing and future wave and turbulence simulations using this type of hybrid model.

  5. Improved Thermoelectric Performance in Flexible Tellurium Nanowires/Reduced Graphene Oxide Sandwich Structure Hybrid Films

    Science.gov (United States)

    Gao, Jie; Liu, Chengyan; Miao, Lei; Wang, Xiaoyang; Peng, Ying; Chen, Yu

    2016-11-01

    With a high flexibility and an adjustable electronic structure, reduced graphene oxide (RGO) is a potential candidate for flexible thermoelectric materials. Here, we report that flexible RGO/tellurium nanowires (Te NWs)/RGO sandwich structure hybrid films are prepared on glass fabrics through the drop-cast method. The addition of 20 wt.% Te NWs into a RGO matrix remarkably improves the Seebeck coefficient from 15.2 μV/K to 89.7 μV/K while maintaining relatively high electrical conductivity, thus resulting in a one order of magnitude higher power factor value compared with the Te NWs. According to the values of carrier mobility and concentration of hybrid films, the improved thermoelectric properties are presented because of the energy filtering effect on the interfaces in hybrid films. This article suggests that RGO/Te NWs/RGO hybrid films would be promising for fabricating flexible energy sources.

  6. Improved Thermoelectric Performance in Flexible Tellurium Nanowires/Reduced Graphene Oxide Sandwich Structure Hybrid Films

    Science.gov (United States)

    Gao, Jie; Liu, Chengyan; Miao, Lei; Wang, Xiaoyang; Peng, Ying; Chen, Yu

    2017-05-01

    With a high flexibility and an adjustable electronic structure, reduced graphene oxide (RGO) is a potential candidate for flexible thermoelectric materials. Here, we report that flexible RGO/tellurium nanowires (Te NWs)/RGO sandwich structure hybrid films are prepared on glass fabrics through the drop-cast method. The addition of 20 wt.% Te NWs into a RGO matrix remarkably improves the Seebeck coefficient from 15.2 μV/K to 89.7 μV/K while maintaining relatively high electrical conductivity, thus resulting in a one order of magnitude higher power factor value compared with the Te NWs. According to the values of carrier mobility and concentration of hybrid films, the improved thermoelectric properties are presented because of the energy filtering effect on the interfaces in hybrid films. This article suggests that RGO/Te NWs/RGO hybrid films would be promising for fabricating flexible energy sources.

  7. Outage Performance of Hybrid FSO/RF System with Low-Complexity Power Adaptation

    KAUST Repository

    Rakia, Tamer

    2016-02-26

    Hybrid free-space optical (FSO) / radio-frequency (RF) systems have emerged as a promising solution for high data- rate wireless communication systems. We consider truncated channel inversion based power adaptation strategy for coherent and non- coherent hybrid FSO/RF systems, employing an adaptive combining scheme. Specifically, we activate the RF link along with the FSO link when FSO link quality is unacceptable, and adaptively set RF transmission power to ensure constant combined signal-to-noise ratio at receiver terminal. Analytical expressions for the outage probability of the hybrid system with and without power adaptation are derived. Numerical examples show that, the hybrid FSO/RF systems with power adaptation achieve considerable outage performance improvement over conventional hybrid FSO/RF systems without power adaptation. © 2015 IEEE.

  8. Atomistic Origins of High-Performance in Hybrid Halide Perovskite Solar Cells

    Science.gov (United States)

    2014-01-01

    The performance of organometallic perovskite solar cells has rapidly surpassed that of both conventional dye-sensitized and organic photovoltaics. High-power conversion efficiency can be realized in both mesoporous and thin-film device architectures. We address the origin of this success in the context of the materials chemistry and physics of the bulk perovskite as described by electronic structure calculations. In addition to the basic optoelectronic properties essential for an efficient photovoltaic device (spectrally suitable band gap, high optical absorption, low carrier effective masses), the materials are structurally and compositionally flexible. As we show, hybrid perovskites exhibit spontaneous electric polarization; we also suggest ways in which this can be tuned through judicious choice of the organic cation. The presence of ferroelectric domains will result in internal junctions that may aid separation of photoexcited electron and hole pairs, and reduction of recombination through segregation of charge carriers. The combination of high dielectric constant and low effective mass promotes both Wannier-Mott exciton separation and effective ionization of donor and acceptor defects. The photoferroic effect could be exploited in nanostructured films to generate a higher open circuit voltage and may contribute to the current–voltage hysteresis observed in perovskite solar cells. PMID:24684284

  9. Performance of hybrid photon detector prototypes with 80% active area for the RICH counters of LHCb

    CERN Document Server

    Albrecht, E; Barber, G J; Bibby, J H; Campbell, M; Duane, A; Gys, Thierry; Montenegro, J; Piedigrossi, D; Schomaker, R; Snoeys, W; Wotton, S A; Wyllie, Ken H

    2000-01-01

    We report on the ongoing work towards a hybrid photon detector with integrated Si pixel readout for the ring imaging Cherenkov detectors of the LHCb experiment at the Large Hadron Collider at CERN. The photon detector is based on an electrostatically focussed image intensifier tube geometry where the image is de-magnified by a factor of ~5. The anode consists of a silicon pixel array, bump-bonded to a binary readout chip with matching pixel electronics. The performance of full-scale prototypes equipped with 61-pixel anodes and external analogue readout is presented. The average signal-to-noise ratio is ~11 with a peaking time of 1.2 mu s. The tube active-to-total surface ratio is 81.7%, which meets the LHCb requirements. The spatial precision is measured to be better than 90 mu m. A cluster of three such tubes has been installed in the LHCb RICH 1 prototype where Cherenkov gas rings have been successfully detected. Progress towards the encapsulation of new pixel electronics into a tube is also reported. In pa...

  10. A mild route to mesoporous Mo2C-C hybrid nanospheres for high performance lithium-ion batteries

    Science.gov (United States)

    Gao, Qing; Zhao, Xinyu; Xiao, Ying; Zhao, Di; Cao, Minhua

    2014-05-01

    the nanohybridization, effectively relieving the volume change during the repeated lithium insertion-extraction reactions and maintaining the integrity of the electrical connections. It is expected that the present synthesis strategy for the Mo2C-C hybrid can be extended to other nanostructured carbides with good energy storage performance. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr06678a

  11. Fuel cell-gas turbine hybrid system design part I: Steady state performance

    Science.gov (United States)

    McLarty, Dustin; Brouwer, Jack; Samuelsen, Scott

    2014-07-01

    The hybridization of gas turbine technology with high temperature fuel cells represents an ultra-high efficiency, ultra-low emission, fuel flexible power generation platform. The performance of past prototypes has been limited by marginal compatibility of the two primary sub-systems. This paper addresses the challenge of selecting compatible hardware by presenting a simple and robust method for bespoke hybrid system design and off-the-shelf component integration. This is the first application of detailed, spatially resolved, physical models capable of resolving off-design performance to the integration analysis of FC-GT hybrids. Static maps are produced for both turbine and fuel cell sub-systems that readily evaluate the compatibility and hybrid performance. Molten carbonate and solid oxide fuel cells are considered for hybridization with recuperated micro-turbines and larger axial flow gas turbine systems. Current state-of-the-art molten carbonate technology is shown to pair well with present micro-turbine technology in an FC bottoming cycle design achieving 74.4% LHV efficiency. Solid oxide technology demonstrates remarkable potential for integration with larger scale axial turbo-machinery to achieve greater than 75% LHV efficiency. This performance map technique closely matches results from detailed integrated hybrid system analyses, and enables quick determination of performance requirements for balance of plant design and optimization.

  12. Hybrid two-dimensional electronic systems and other applications of sp-2 bonded light elements

    Science.gov (United States)

    Kessler, Brian Maxwell

    The field-effect is a cornerstone of modern technology lying at the heart of transistors in consumer electronics. Experimentally, it allows one to continuously vary the carrier concentration in a material while studying its properties. The recent isolation of graphene, the first truly two-dimensional crystal, allows application of the field effect to a much wider range of physical situations. In the first part of the thesis, we investigate hybrid materials formed by coupling metals to the two-dimensional electron gas (2DEG) in graphene. We couple superconducting materials to the graphene sheet by cluster deposition. This material displays a superconducting phase whose properties are tuned by the carrier density via the field effect. The transition temperature is well-described by Berezinskii-Kosterlitz-Thouless vortex unbinding. The ground state properties show interesting effects due to the distribution of cluster spacings. Observations related to other hybrid electronic systems including ferromagnets and normal metals are presented. The second part of this thesis involves energy applications of light element materials. The mechanisms affecting coating of carbon nanotubes using atomic layer deposition is developed and applied to photovoltaic systems. The gas adsorption properties of activated boron nitride are investigated and the relative influence of surface area and hydrogen binding affinity is elaborated. The third part of this thesis explores electromechanical properties of suspended graphene membranes. We investigate buckling and strain in exfoliated graphene membranes as well as their deformation under an applied gate potential.

  13. Bionano donor-acceptor hybrids of porphyrin, ssDNA, and semiconductive single-wall carbon nanotubes for electron transfer via porphyrin excitation.

    Science.gov (United States)

    D'Souza, Francis; Das, Sushanta K; Zandler, Melvin E; Sandanayaka, Atula S D; Ito, Osamu

    2011-12-14

    Photoinduced electron transfer in self-assemblies of porphyrins ion-paired with ssDNA wrapped around single-wall carbon nanotubes (SWCNTs) has been reported. To accomplish the three-component hybrids, two kinds of diameter-sorted semiconducting SWCNT(n,m)s of different diameter ((n,m) = (6,5) and (7,6)) and free-base or zinc porphyrin bearing peripheral positive charges ((TMPyP(+))M (tetrakis(4-N-methylpyridyl)porphyrin); M = Zn and H(2)) serving as light-absorbing photoactive materials are utilized. The donor-acceptor hybrids are held by ion-pairing between the negatively charged phosphate groups of ssDNA on the surface of the SWCNT and the positively charged at the ring periphery porphyrin macrocycle. The newly assembled bionano donor-acceptor hybrids have been characterized by transmission electron microscopy (TEM) and spectroscopic methods. Photoinduced electron transfer from the excited singlet porphyrin to the SWCNTs directly and/or via ssDNA as an electron mediator has been established by performing systematic studies involving the steady-state and time-resolved emission as well as the transient absorption studies. Higher charge-separation efficiency has been successfully demonstrated by the selection of the appropriate semiconductive SWCNTs with the right band gap, in addition to the aid of ssDNA as the electron mediator. © 2011 American Chemical Society

  14. Perylenes as sensitizers in hybrid solar cells : how molecular size influences performance

    NARCIS (Netherlands)

    Li, Chen; Liu, Zhihong; Schoneboom, Jan; Eickemeyer, Felix; Pschirer, Neil G.; Erk, Peter; Herrmann, Andreas; Mullen, Klaus; Schöneboom, Jan; Grätzel, Michael; Janssen, René

    2009-01-01

    Dye-sensitized solar cells (DSCs), one kind of hybrid solar cells, are being intensively developed due to their high efficiency and low cost. One of the main factors to improve the efficiency is the minimization of the recombination of holes and electrons at the TiO(2)/dye/electrolyte interface. To

  15. TOPICAL REVIEW: Optics of high-performance electron microscopes

    OpenAIRE

    H H Rose

    2008-01-01

    During recent years, the theory of charged particle optics together with advances in fabrication tolerances and experimental techniques has lead to very significant advances in high-performance electron microscopes. Here, we will describe which theoretical tools, inventions and designs have driven this development. We cover the basic theory of higher-order electron optics and of image formation in electron microscopes. This leads to a description of different methods to correct aberrations by...

  16. Composite Strain Hardening Properties of High Performance Hybrid Fibre Reinforced Concrete

    Directory of Open Access Journals (Sweden)

    Vikram Jothi Jayakumar

    2014-01-01

    Full Text Available Hybrid fibres addition in concrete proved to be a promising method to improve the composite mechanical properties of the cementitious system. Fibre combinations involving different fibre lengths and moduli were added in high strength slag based concrete to evaluate the strain hardening properties. Influence of hybrid fibres consisting of steel and polypropylene fibres added in slag based cementitious system (50% CRL was explored. Effects of hybrid fibre addition at optimum volume fraction of 2% of steel fibres and 0.5% of PP fibres (long and short steel fibre combinations were observed in improving the postcrack strength properties of concrete. Test results also indicated that the hybrid steel fibre additions in slag based concrete consisting of short steel and polypropylene (PP fibres exhibited a the highest compressive strength of 48.56 MPa. Comparative analysis on the performance of monofibre concrete consisting of steel and PP fibres had shown lower residual strength compared to hybrid fibre combinations. Hybrid fibres consisting of long steel-PP fibres potentially improved the absolute and residual toughness properties of concrete composite up to a maximum of 94.38% compared to monofibre concrete. In addition, the relative performance levels of different hybrid fibres in improving the matrix strain hardening, postcrack toughness, and residual strength capacity of slag based concretes were evaluated systematically.

  17. Performance modeling of hybrid MPI/OpenMP scientific applications on large-scale multicore supercomputers

    KAUST Repository

    Wu, Xingfu

    2013-12-01

    In this paper, we present a performance modeling framework based on memory bandwidth contention time and a parameterized communication model to predict the performance of OpenMP, MPI and hybrid applications with weak scaling on three large-scale multicore supercomputers: IBM POWER4, POWER5+ and BlueGene/P, and analyze the performance of these MPI, OpenMP and hybrid applications. We use STREAM memory benchmarks and Intel\\'s MPI benchmarks to provide initial performance analysis and model validation of MPI and OpenMP applications on these multicore supercomputers because the measured sustained memory bandwidth can provide insight into the memory bandwidth that a system should sustain on scientific applications with the same amount of workload per core. In addition to using these benchmarks, we also use a weak-scaling hybrid MPI/OpenMP large-scale scientific application: Gyrokinetic Toroidal Code (GTC) in magnetic fusion to validate our performance model of the hybrid application on these multicore supercomputers. The validation results for our performance modeling method show less than 7.77% error rate in predicting the performance of hybrid MPI/OpenMP GTC on up to 512 cores on these multicore supercomputers. © 2013 Elsevier Inc.

  18. Analysis of Performance and Designing of Bi-Quad Filter using Hybrid Signed digit Number System

    Directory of Open Access Journals (Sweden)

    Sugandha Agarwal

    2012-03-01

    Full Text Available Speed of digital arithmetic processor depends mainly on the speed of adders. This paper provides a technique so that we can increase the speed of addition. Hybrid signed digit number representation perform addition in such a way that the carry propagation chain is limited to single digit position and hence are used to speed up arithmetic operation. Also hybrid signed digit reduces the critical path delay by parallelizing. Hybrid signed digit can be appropriate to use, when output is redundant representation.

  19. Graphene–Selenium Hybrid Microballs as Cathode Materials for High-performance Lithium–Selenium Secondary Battery Applications

    Science.gov (United States)

    Youn, Hee-Chang; Jeong, Jun Hui; Roh, Kwang Chul; Kim, Kwang-Bum

    2016-08-01

    In this study, graphene–selenium hybrid microballs (G–SeHMs) are prepared in one step by aerosol microdroplet drying using a commercial spray dryer, which represents a simple, scalable continuous process, and the potential of the G–SeHMs thus prepared is investigated for use as cathode material in applications of lithium–selenium secondary batteries. These morphologically unique graphene microballs filled with Se particles exhibited good electrochemical properties, such as high initial specific capacity (642 mA h g‑1 at 0.1 C, corresponding to Se electrochemical utilisation as high as 95.1%), good cycling stability (544 mA h g‑1 after 100 cycles at 0.1 C 84.5% retention) and high rate capability (specific capacity of 301 mA h g‑1 at 5 C). These electrochemical properties are attributed to the fact that the G–SeHM structure acts as a confinement matrix for suppressing the dissolution of polyselenides in the organic electrolyte, as well as an electron conduction path for increasing the transport rate of electrons for electrochemical reactions. Notably, based on the weight of hybrid materials, electrochemical performance is considerably better than that of previously reported Se-based cathode materials, attributed to the high Se loading content (80 wt%) in hybrid materials.

  20. Brake Performance Analysis of ABS for Eddy Current and Electrohydraulic Hybrid Brake System

    Directory of Open Access Journals (Sweden)

    Ren He

    2013-01-01

    Full Text Available This paper introduces an eddy current and electro-hydraulic hybrid brake system to solve problems such as wear, thermal failure, and slow response of traditional vehicle brake system. Mathematical model was built to calculate the torque of the eddy current brake system and hydraulic brake system and analyze the braking force distribution between two types of brake systems. A fuzzy controller on personal computer based on LabVIEW and Matlab was designed and a set of hardware in the loop system was constructed to validate and analyze the performance of the hybrid brake system. Through lots of experiments on dry and wet asphalt roads, the hybrid brake system achieves perfect performance on the experimental bench, the hybrid system reduces abrasion and temperature of the brake disk, response speed is enhanced obviously, fuzzy controller keeps high utilization coefficient due to the optimal slip ratio regulation, and the total brake time has a smaller decrease than traditional hydraulic brake system.

  1. Effects of electronic outlining on students’ argumentative writing performance

    NARCIS (Netherlands)

    De Smet, Milou; Broekkamp, Hein; Brand-Gruwel, Saskia; Kirschner, Paul A.

    2011-01-01

    De Smet, M. J. R., Broekkamp, H., Brand-Gruwel, S., & Kirschner, P. A. (2011, August). Effects of electronic outlining on students’ argumentative writing performance. Presentation at EARLI, Exeter, UK.

  2. Donor-acceptor graphene-based hybrid materials facilitating photo-induced electron-transfer reactions.

    Science.gov (United States)

    Stergiou, Anastasios; Pagona, Georgia; Tagmatarchis, Nikos

    2014-01-01

    Graphene research and in particular the topic of chemical functionalization of graphene has exploded in the last decade. The main aim is to increase the solubility and thereby enhance the processability of the material, which is otherwise insoluble and inapplicable for technological applications when stacked in the form of graphite. To this end, initially, graphite was oxidized under harsh conditions to yield exfoliated graphene oxide sheets that are soluble in aqueous media and amenable to chemical modifications due to the presence of carboxylic acid groups at the edges of the lattice. However, it was obvious that the high-defect framework of graphene oxide cannot be readily utilized in applications that are governed by charge-transfer processes, for example, in solar cells. Alternatively, exfoliated graphene has been applied toward the realization of some donor-acceptor hybrid materials with photo- and/or electro-active components. The main body of research regarding obtaining donor-acceptor hybrid materials based on graphene to facilitate charge-transfer phenomena, which is reviewed here, concerns the incorporation of porphyrins and phthalocyanines onto graphene sheets. Through illustrative schemes, the preparation and most importantly the photophysical properties of such graphene-based ensembles will be described. Important parameters, such as the generation of the charge-separated state upon photoexcitation of the organic electron donor, the lifetimes of the charge-separation and charge-recombination as well as the incident-photon-to-current efficiency value for some donor-acceptor graphene-based hybrids, will be discussed.

  3. Hybrid Numerical Solvers for Massively Parallel Eigenvalue Computation and Their Benchmark with Electronic Structure Calculations

    CERN Document Server

    Imachi, Hiroto

    2015-01-01

    Optimally hybrid numerical solvers were constructed for massively parallel generalized eigenvalue problem (GEP).The strong scaling benchmark was carried out on the K computer and other supercomputers for electronic structure calculation problems in the matrix sizes of M = 10^4-10^6 with upto 105 cores. The procedure of GEP is decomposed into the two subprocedures of the reducer to the standard eigenvalue problem (SEP) and the solver of SEP. A hybrid solver is constructed, when a routine is chosen for each subprocedure from the three parallel solver libraries of ScaLAPACK, ELPA and EigenExa. The hybrid solvers with the two newer libraries, ELPA and EigenExa, give better benchmark results than the conventional ScaLAPACK library. The detailed analysis on the results implies that the reducer can be a bottleneck in next-generation (exa-scale) supercomputers, which indicates the guidance for future research. The code was developed as a middleware and a mini-application and will appear online.

  4. Highly transparent, low-haze, hybrid cellulose nanopaper as electrodes for flexible electronics.

    Science.gov (United States)

    Xu, Xuezhu; Zhou, Jian; Jiang, Long; Lubineau, Gilles; Ng, Tienkhee; Ooi, Boon S; Liao, Hsien-Yu; Shen, Chao; Chen, Long; Zhu, J Y

    2016-06-16

    Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are still characterized by high diffuse transmittance and small direct transmittance, resulting in high optical haze of the substrates. In this study, we proposed a simple methodology for large-scale production of high-transparency, low-haze CNP comprising both long cellulose nanofibrils (CNFs) and short cellulose nanocrystals (CNCs). By varying the CNC/CNF ratio in the hybrid CNP, we could tailor its total transmittance, direct transmittance and diffuse transmittance. By increasing the CNC content, the optical haze of the hybrid CNP could be decreased and its transparency could be increased. The direct transmittance and optical haze of the CNP were 75.1% and 10.0%, respectively, greatly improved from the values of previously reported CNP (31.1% and 62.0%, respectively). Transparent, flexible electrodes were fabricated by coating the hybrid CNP with silver nanowires (AgNWs). The electrodes showed a low sheet resistance (minimum 1.2 Ω sq(-1)) and a high total transmittance (maximum of 82.5%). The electrodes were used to make a light emitting diode (LED) assembly to demonstrate their potential use in flexible displays.

  5. Functional Carbon Nanotube/Mesoporous Carbon/MnO2 Hybrid Network for High-Performance Supercapacitors

    Directory of Open Access Journals (Sweden)

    Tao Tao

    2014-01-01

    Full Text Available A functional carbon nanotube/mesoporous carbon/MnO2 hybrid network has been developed successfully through a facile route. The resulting composites exhibited a high specific capacitance of 351 F/g at 1 A g−1, with intriguing charge/discharge rate performance and cycling stability due to a synergistic combination of large surface area and excellent electron-transport capabilities of MnO2 with the good conductivity of the carbon nanotube/mesoporous carbon networks. Such composite shows great potential to be used as electrodes for supercapacitors.

  6. Hybrid carbon nanostructure assemblage for high performance pseudo-capacitors

    Directory of Open Access Journals (Sweden)

    A. K. Mishra

    2012-06-01

    Full Text Available Investigation of novel nanocomposites for pseudo-capacitors with high capacitance and energy density is the spotlight of current energy research. In the present work, hybrid carbon nanostructure assemblage of graphene and multiwalled carbon nanotubes has been used as carbon support to nanostructured RuO2 and polyaniline for high energy supercapacitors. Maximum specific capacitances of 110, 235 and 440 F g−1 at the voltage sweep rate of 10 mV s−1 and maximum energy densities of 7, 12.5 and 20.5 Wh kg−1 were observed for carbon assemblage and its RuO2 and polyanilne decorated nanocomposites, respectively, with 1M H2SO4 as electrolyte.

  7. Performance Analysis of Hybrid Electric Vehicle over Different Driving Cycles

    Science.gov (United States)

    Panday, Aishwarya; Bansal, Hari Om

    2017-02-01

    Article aims to find the nature and response of a hybrid vehicle on various standard driving cycles. Road profile parameters play an important role in determining the fuel efficiency. Typical parameters of road profile can be reduced to a useful smaller set using principal component analysis and independent component analysis. Resultant data set obtained after size reduction may result in more appropriate and important parameter cluster. With reduced parameter set fuel economies over various driving cycles, are ranked using TOPSIS and VIKOR multi-criteria decision making methods. The ranking trend is then compared with the fuel economies achieved after driving the vehicle over respective roads. Control strategy responsible for power split is optimized using genetic algorithm. 1RC battery model and modified SOC estimation method are considered for the simulation and improved results compared with the default are obtained.

  8. Two-step synthesis of Ag@GQD hybrid with enhanced photothermal effect and catalytic performance

    Science.gov (United States)

    Wu, Cong; Yuan, Yali; He, Qian; Song, Rui

    2016-12-01

    A novel Ag@GQD (graphene quantum dot) hybrid fabricated by a facile two-step strategy is presented: the GQDs are prepared by citrate acid and AgNO3 is reduced. Catalytic studies showed that the Ag@GQD hybrid exhibited excellent photothermal effect and catalytic performance for 4-nitrophenol (4-NP) reduction, suggesting that the GQDs enhanced the catalytic activity via a synergistic effect and the Ag NPs boosted the catalytic efficiency through SPR-mediated photothermal local heating.

  9. ?HY-CHANGE?: AN HYBRID METHODOLOGY FOR CONTINUOUS PERFORMANCE IMPROVEMENT OF MANUFACTURING PROCESSES

    OpenAIRE

    Dassisti, Michele

    2010-01-01

    Abstract An hybrid methodology based on the joint recourse of Business Process An hybrid methodology for Continuous Performance Improvement (CPI) is presented, basically funded on the joint recourse of Business Process Reengineering (BPR) and Continuous Quality Improvement (CQI) principles and tools. The methodology (called HY-CHANGE) is conceived as a logical and technical support to the decision maker. It results in a number of recursive phases, where the rational and synchronous...

  10. Optical Thermal Characterization Enables High-Performance Electronics Applications

    Energy Technology Data Exchange (ETDEWEB)

    2016-02-01

    NREL developed a modeling and experimental strategy to characterize thermal performance of materials. The technique provides critical data on thermal properties with relevance for electronics packaging applications. Thermal contact resistance and bulk thermal conductivity were characterized for new high-performance materials such as thermoplastics, boron-nitride nanosheets, copper nanowires, and atomically bonded layers. The technique is an important tool for developing designs and materials that enable power electronics packaging with small footprint, high power density, and low cost for numerous applications.

  11. A hybrid electron donor comprising cyclopentadithiophene and dithiafulvenyl for dye-sensitized solar cells

    Directory of Open Access Journals (Sweden)

    Gleb Sorohhov

    2015-06-01

    Full Text Available Two new photosensitizers featured with a cyanoacrylic acid electron acceptor (A and a hybrid electron donor (D of cyclopentadithiophene and dithiafulvenyl, either directly linked or separated by a phenyl ring, were synthesized and characterized. Both of them undergo two reversible oxidations and strongly absorb in the visible spectral region due to a photo-induced intramolecular charge-transfer (ICT transition. To a great extent, the electronic interaction between the D and A units is affected by the presence of a phenyl spacer. Without a phenyl ring, the D unit appears more difficult to oxidize due to a strong electron-withdrawing effect of the A moiety. In sharp contrast, the insertion of the phenyl ring between the D and A units leads to a broken π-conjugation and therefore, the oxidation potentials remain almost unchanged compared to those of an analogue without the A group, suggesting that the electronic coupling between D and A units is relatively weak. As a consequence, the lowest-energy absorption band shows a slight hypsochromic shift upon the addition of the phenyl spacer, indicative of an increased HOMO–LUMO gap. In turn, the direct linkage of D and A units leads to an effective π-conjugation, thus substantially lowering the HOMO–LUMO gap. Moreover, the application in dye-sensitized solar cells was investigated, showing that the power conversion efficiency increases by the insertion of the phenyl unit.

  12. A hybrid electron donor comprising cyclopentadithiophene and dithiafulvenyl for dye-sensitized solar cells.

    Science.gov (United States)

    Sorohhov, Gleb; Yi, Chenyi; Grätzel, Michael; Decurtins, Silvio; Liu, Shi-Xia

    2015-01-01

    Two new photosensitizers featured with a cyanoacrylic acid electron acceptor (A) and a hybrid electron donor (D) of cyclopentadithiophene and dithiafulvenyl, either directly linked or separated by a phenyl ring, were synthesized and characterized. Both of them undergo two reversible oxidations and strongly absorb in the visible spectral region due to a photo-induced intramolecular charge-transfer (ICT) transition. To a great extent, the electronic interaction between the D and A units is affected by the presence of a phenyl spacer. Without a phenyl ring, the D unit appears more difficult to oxidize due to a strong electron-withdrawing effect of the A moiety. In sharp contrast, the insertion of the phenyl ring between the D and A units leads to a broken π-conjugation and therefore, the oxidation potentials remain almost unchanged compared to those of an analogue without the A group, suggesting that the electronic coupling between D and A units is relatively weak. As a consequence, the lowest-energy absorption band shows a slight hypsochromic shift upon the addition of the phenyl spacer, indicative of an increased HOMO-LUMO gap. In turn, the direct linkage of D and A units leads to an effective π-conjugation, thus substantially lowering the HOMO-LUMO gap. Moreover, the application in dye-sensitized solar cells was investigated, showing that the power conversion efficiency increases by the insertion of the phenyl unit.

  13. Tunable Radiation Response in Hybrid Organic-Inorganic Gate Dielectrics for Low-Voltage Graphene Electronics.

    Science.gov (United States)

    Arnold, Heather N; Cress, Cory D; McMorrow, Julian J; Schmucker, Scott W; Sangwan, Vinod K; Jaber-Ansari, Laila; Kumar, Rajan; Puntambekar, Kanan P; Luck, Kyle A; Marks, Tobin J; Hersam, Mark C

    2016-03-01

    Solution-processed semiconductor and dielectric materials are attractive for future lightweight, low-voltage, flexible electronics, but their response to ionizing radiation environments is not well understood. Here, we investigate the radiation response of graphene field-effect transistors employing multilayer, solution-processed zirconia self-assembled nanodielectrics (Zr-SANDs) with ZrOx as a control. Total ionizing dose (TID) testing is carried out in situ using a vacuum ultraviolet source to a total radiant exposure (RE) of 23.1 μJ/cm(2). The data reveal competing charge density accumulation within and between the individual dielectric layers. Additional measurements of a modified Zr-SAND show that varying individual layer thicknesses within the gate dielectric tuned the TID response. This study thus establishes that the radiation response of graphene electronics can be tailored to achieve a desired radiation sensitivity by incorporating hybrid organic-inorganic gate dielectrics.

  14. Detection of secondary electrons with pixelated hybrid semiconductor detectors; Sekundaerelektronennachweis mit pixelierten hybriden Halbleiterdetektoren

    Energy Technology Data Exchange (ETDEWEB)

    Gebert, Ulrike Sonja

    2011-09-14

    Within the scope of this thesis, secondary electrons were detected with a pixelated semiconductor detector named Timepix. The Timepix detector consists of electronics and a sensor made from a semiconductor material. The connection of sensor and electronics is done for each pixel individually using bump bonds. Electrons with energies above 3 keV can be detected with the sensor. One electron produces a certain amount of electron-hole pairs according to its energy. The charge then drifts along an electric field to the pixel electronics, where it induces an electric signal. Even without a sensor it is possible to detect an electric signal from approximately 1000 electrons directly in the pixel electronics. Two different detector systems to detect secondary electrons using the Timepix detector were investigated during this thesis. First of all, a hybrid photon detector (HPD) was used to detect single photoelectrons. The HPD consists of a vacuum vessel with an entrance window and a cesium iodine photocathode at the inner surface of the window. Photoelectrons are released from the photocathode by incident light and are accelerated in an electric field towards the Timepix detector, where the point of interaction and the arrival time of the electron is determined. With a proximity focusing setup, a time resolution of 12 ns (with an acceleration voltage of 20 kV between photocathode and Timepix detector) was obtained. The HPD examined in this thesis showed a strong dependence of the dark rate form the acceleration voltage and the pressure in the vacuum vessel. At a pressure of few 10{sup -5} mbar and an acceleration voltage of 20 kV, the dark rate was about 800 Hz per mm{sup 2} area of the read out photocathode. One possibility to reduce the dark rate is to identify ion feedback events. With a slightly modified setup it was possible to reduce the dark rate to 0.5 Hz/mm{sup 2}. To achieve this, a new photocathode was mounted in a shorter distance to the detector. The

  15. Femtosecond timing-jitter between photo-cathode laser and ultra-short electron bunches by means of hybrid compression

    Science.gov (United States)

    Pompili, R.; Anania, M. P.; Bellaveglia, M.; Biagioni, A.; Castorina, G.; Chiadroni, E.; Cianchi, A.; Croia, M.; Di Giovenale, D.; Ferrario, M.; Filippi, F.; Gallo, A.; Gatti, G.; Giorgianni, F.; Giribono, A.; Li, W.; Lupi, S.; Mostacci, A.; Petrarca, M.; Piersanti, L.; Di Pirro, G.; Romeo, S.; Scifo, J.; Shpakov, V.; Vaccarezza, C.; Villa, F.

    2016-08-01

    The generation of ultra-short electron bunches with ultra-low timing-jitter relative to the photo-cathode (PC) laser has been experimentally proved for the first time at the SPARC_LAB test-facility (INFN-LNF, Frascati) exploiting a two-stage hybrid compression scheme. The first stage employs RF-based compression (velocity-bunching), which shortens the bunch and imprints an energy chirp on it. The second stage is performed in a non-isochronous dogleg line, where the compression is completed resulting in a final bunch duration below 90 fs (rms). At the same time, the beam arrival timing-jitter with respect to the PC laser has been measured to be lower than 20 fs (rms). The reported results have been validated with numerical simulations.

  16. Femtosecond timing-jitter between photo-cathode laser and ultra-short electron bunches by means of hybrid compression

    CERN Document Server

    Pompili, Riccardo; Bellaveglia, M; Biagioni, A; Castorina, G; Chiadroni, E; Cianchi, A; Croia, M; Di Giovenale, D; Ferrario, M; Filippi, F; Gallo, A; Gatti, G; Giorgianni, F; Giribono, A; Li, W; Lupi, S; Mostacci, A; Petrarca, M; Piersanti, L; Di Pirro, G; Romeo, S; Scifo, J; Shpakov, V; Vaccarezza, C; Villa, F

    2017-01-01

    The generation of ultra-short electron bunches with ultra-low timing-jitter relative to the photo-cathode (PC) laser has been experimentally proved for the first time at the SPARC_LAB test-facility (INFN-LNF, Frascati) exploiting a two-stage hybrid compression scheme. The first stage employs RF-based compression (velocity-bunching), which shortens the bunch and imprints an energy chirp on it. The second stage is performed in a non-isochronous dogleg line, where the compression is completed resulting in a final bunch duration below 90 fs (rms). At the same time, the beam arrival timing-jitter with respect to the PC laser has been measured to be lower than 20 fs (rms). The reported results have been validated with numerical simulations.

  17. Design of hybrid sol gel films for direct x-ray and electron beam nanopatterning

    Science.gov (United States)

    Brusatin, Giovanna; Della Giustina, Gioia; Romanato, Filippo; Guglielmi, Massimo

    2008-04-01

    New epoxy based sol-gel organic inorganic materials, showing lithographic resist-like properties without the addition of any photocatalysts, are presented. To obtain a material sensitive to radiation, specific sol-gel syntheses based on an organically modified alkoxide containing an epoxy ring, 3-glycidoxypropyltrimethoxysilane (GPTMS), have been developed. The synthesis and the patternability of hybrid materials have been obtained controlling the inorganic crosslinking degree and with an almost total absence of organic polymerization. Two examples of directly patternable hybrid films, called GB and GGe, have been synthesized using acidic (GGe) and basic (GB) conditions and obtaining different compositions. After electron beam lithography (EBL) or x-ray synchrotron radiation lithography (XRL) the polymerization of the organic component of the sol-gel film occurs, generating a hardening of the structure after post-exposure baking. The exposed polymerized material becomes insoluble, determining a negative resist-like behaviour of the film: the lithographic process of nanopatterning results from the dissolution of the unexposed areas in proper solvents (developers). Spatial resolution of the order of 200 nm is reported and a contrast of 2.2 is achieved. The novelty of this work is that epoxy based materials, which have enhanced thermomechanical stability with respect to the more usual acrylic based resins, are directly nanopatterned for the first time by electron beam (EB) and/or x-ray beam radiation exposure without the aid of catalysts for polymerization. In contrast to common resists that are sacrificial layers of the fabrication process, direct patternable sol-gel hybrids constitute the final material of the devices. In fact, an example of doping with a light emitting dye is reported together with the achievement of directly patterned structures by EBL and XRL.

  18. Hybrid CIS-DFT method to study electric field effects on electronic excited states of ethylene

    Institute of Scientific and Technical Information of China (English)

    Ma Mei-Zhong; Zhu Zheng-He; Chen Xiao-Jun; Xu Guo-Liang; Zhang Yong-Bin; Mao Hua-Ping; Shen Xiao-Hong

    2005-01-01

    The present work is devoted to the study of the effects of external dipole electric field on the molecular structure of ethylene using a hybrid method which combines the single-excitation configuration interactions (CIS) with density functional theory (DFT), i.e. CIS-DFT(B3LYP). It is found that the effects of electric dipole field on the molecular geometry (D2h, D2d and C2v), dipole moment, transition dipole moment, polarizability and, particularly, excitation energy of ethylene are remarkable. The advantages of the hybrid CIS-DFT method are that it can determine the symmetry of molecule and the correct order of excitation as well as the Molecular Orbital (MO) electron configuration;thereby the electronic excitation states of ethylene are easily derived, and most of them are in agreement with those obtained in experiments or references. It may be the first time the effects of external electric field on ethylene molecule have been considered. Compared with other ab initio methods, the CIS-DFT method is relatively accurate and low cost in computation. We expect that it can be used to study other closed-shell molecules.

  19. High Energy Density Additives for Hybrid Fuel Rockets to Improve Performance and Enhance Safety

    Science.gov (United States)

    Jaffe, Richard L.

    2014-01-01

    We propose a conceptual study of prototype strained hydrocarbon molecules as high energy density additives for hybrid rocket fuels to boost the performance of these rockets without compromising safety and reliability. Use of these additives could extend the range of applications for which hybrid rockets become an attractive alternative to conventional solid or liquid fuel rockets. The objectives of the study were to confirm and quantify the high enthalpy of these strained molecules and to assess improvement in rocket performance that would be expected if these additives were blended with conventional fuels. We confirmed the chemical properties (including enthalpy) of these additives. However, the predicted improvement in rocket performance was too small to make this a useful strategy for boosting hybrid rocket performance.

  20. Gas-Transport-Property Performance of Hybrid Carbon Molecular Sieve−Polymer Materials

    KAUST Repository

    Das, Mita

    2010-10-06

    High-performance hybrid materials using carbon molecular sieve materials and 6FDA-6FpDA were produced. A detailed analysis of the effects of casting processes and the annealing temperature is reported. Two existing major obstacles, sieve agglomeration and residual stress, were addressed in this work, and subsequently a new membrane formation technique was developed to produce high-performing membranes. The successfully improved interfacial region of the hybrid membranes allows the sieves to increase the selectivity of the membranes above the neat polymer properties. Furthermore, an additional performance enhancement was seen with increased sieve loading in the hybrid membranes, leading to an actual performance above the upper bound for pure polymer membranes. The membranes were also tested under a mixed-gas environment, which further demonstrated promising results. © 2010 American Chemical Society.

  1. Development of eggplant hybrid cultivar ‘BATEM FILIZI’ and determination of yield performance

    Directory of Open Access Journals (Sweden)

    Hatice Filiz BOYACI

    2014-12-01

    Full Text Available Eggplant (Solanum melongena L. cultivation is an important part of vegetable production in Turkey. It is highly affected by abiotic stress factors such as low temperatures during growth and development. The present study was aimed to improve new hybrid varieties with high quality and fruit setting under undesirable environmental conditions in eggplant. The 39 inbred lines were developed from eggplant genepool by using pedigree breeding method at the Bati Akdeniz Agricultural Research Institute. They were characterized morphologically and evaluated for phylogenetic relationship among them. Selected seven lines were crossed each other to obtain F1 hybrids. Thirteen hybrids from these crosses were examined for their rate of heterosis and heterobeltiosis. These hybrids were not suitable for market demands although F1 hybrids including P350 as parental line had high heterosis rate. Oval fruit shaped P350 inbred line as female parent showed good performance and crossed with long fruit shaped P599 inbred line. The resultant F1 hybrid cultivar higher yielding, suitable for production under greenhouse and highly adaptable was registered with the name of BATEM FILIZI. It is recommended that this hybrid can be used in greenhouse production especially in single crop season.

  2. Performance Investigation of a Full-Scale Hybrid Composite Bull Gear

    Science.gov (United States)

    LaBerge, Kelsen; Handschuh, Robert; Roberts, Gary; Thorp, Scott

    2016-01-01

    Hybrid composite gears have been investigated as a weight saving technology for rotorcraft transmissions. These gears differ from conventional steel gears in that the structural material between the shaft interface and the gear rim is replaced with a lightweight carbon fiber composite. The work discussed here is an extension of previous coupon level hybrid gear tests to a full-scale bull gear. The NASA Glenn Research Center High-Speed Helical Gear Rig was modified for this program allowing several hybrid gear web configurations to be tested while utilizing the same gear rim. Testing was performed on both a baseline (steel) web configuration and a hybrid (steel-composite)configuration. Vibration, orbit and temperature data were recorded and compared between configurations. Vibration levels did not differ greatly between the hybrid and steel configurations, nor did temperature differential between inlet and outlet. While orbit shape displayed differences between the hybrid and baseline configurations, the general overall amplitude was comparable. The hybrid configuration discussed here successfully ran at 3300 hp(2,460 kW), however, progressive growth of the orbit while running at this test condition discontinued the test. Researchers continue to search for the cause of this orbit shift.

  3. Performance Investigation of a Full-Scale Hybrid Composite Bull Gear

    Science.gov (United States)

    Laberge, Kelsen E.; Handschuh, Robert F.; Roberts, Gary; Thorp, Scott

    2016-01-01

    Hybrid composite gears have been investigated as a weight saving technology for rotorcraft transmissions. These gears differ from conventional steel gears in that the structural material between the shaft interface and the gear rim is replaced with a lightweight carbon fiber composite. The work discussed here is an extension of previous coupon level hybrid gear tests to a full-scale bull gear. The NASA Glenn Research Center High-Speed Helical Gear Rig was modified for this program, allowing several hybrid gear web configurations to be tested while utilizing the same gear rim. Testing was performed on both a baseline (steel) web configuration and a hybrid (steel-composite) configuration. Vibration, orbit and temperature data were recorded and compared between configurations. Vibration levels did not differ greatly between the hybrid and steel configurations, nor did temperature differential between inlet and outlet. While orbit shape displayed differences between the hybrid and baseline configurations, the general overall amplitude was comparable. The hybrid configuration discussed here successfully ran at 3300 hp (2,460 kW), however, progressive growth of the orbit while running at this test condition discontinued the test. Further studies are planned to determine the cause of this behavior.

  4. Performance Study on ST/JT Hybrid Cryocoolers Working at Liquid Helium Temperature

    Science.gov (United States)

    Dongli, Liu; Xuan, Tao; Xiao, Sun; Zhihua, Gan

    The ST/JT hybridcryocooler consists of a Stirling-typecryocooler and a J-T loop. The common process of steady-state operation is given. Pressure-Enthalpy map analysis and thermodynamic calculation showhow the precooling temperature, high pressure and recuperator effectiveness affect thecooling powerat liquid helium temperature. Applying the current performance level of the Stirling cooler,the overall COP of the hybrid cryocooleris roughly optimized. This performance study shows that the hybrid cryocooler can develop its performance potential with improved J-T compressors with larger pressure ratio and aprecooler working at lower temperature.

  5. An experimental performance evaluation of the hybrid FSO/RF

    Science.gov (United States)

    Touati, Abir; Touati, Farid; Abdaoui, Abderrazak; Khandakar, Amith; Hussain, Syed Jawad; Bouallegue, Ammar

    2017-02-01

    This paper is a first attempt to study the effects of atmospheric turbulences on hybrid free space optics/ radio frequency (FSO/RF) transmission system in Doha, Qatar. The state of Qatar is characterized by a Mediterranean climate with hot and dry summers with modest cloud coverage highly affected by airborne dust. Due to its sensitivity to atmospheric turbulences, throughout this study, we try to demonstrate the working capabilities of FSO technology as well as to promote an understanding of this technology amongst the countries of the gulf cooperation council (GCC). Moreover, we studied the behavior of RF link during the same period. In order to analyze the transport media, two transmitting subsystems are employed and installed at Qatar University (QU) at two different buildings separated by a distance of 600 m. Each system is composed of a FSO and RF terminal. We have ported an Embedded Linux kernel on Micro-blaze processor build in Field Programmable Gate Array (FPGA). Then, we have designed a network sniffer application that can run on the FPGA board. The measurements from the network sniffer applications were carried out during summer season from June up to September 2015. The relation between the measurements and the atmospheric factors, taken from a weather station installed at QU, were also found.

  6. High-performance cryogenic fractal 180° hybrid power divider with integrated directional coupler

    Science.gov (United States)

    Ladu, Adelaide; Montisci, Giorgio; Valente, Giuseppe; Navarrini, Alessandro; Marongiu, Pasqualino; Pisanu, Tonino; Mazzarella, Giuseppe

    2017-06-01

    A 180° hybrid and a directional coupler to be employed in the P-band cryogenic receiver of the Sardinia Radio Telescope are proposed in this work. An in-depth study of the issues related to the use of microwave components for cryogenic radio astronomy receivers is carried out to select the best suited technology and configuration. As a result, a planar fractal 180° hybrid configuration available in the literature has been optimized aiming to increase the operating bandwidth in order to comply with the design specifications of the application at hand. A coupled line directional coupler with weak coupling and high isolation, used to calibrate the receiver chain, is cascaded to the 180° hybrid and realized in the same layout. The final device, consisting of the 180° hybrid and the directional coupler, has been manufactured and tested at the cryogenic temperature of 20 K, showing a good agreement between experimental results and predicted performance.

  7. Preparation, characterisation, engine performance and emission characteristics of coconut oil based hybrid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Pranil J.; Singh, Anirudh [Division of Physics, School of Engineering and Physics, Faculty of Science, Technology and Environment, University of the South Pacific, 325 Fletcher Road, Suva (Fiji); Khurma, Jagjit [Division of Chemistry, School of Biological, Chemical and Environmental Sciences, Faculty of Science, Technology and Environment, University of the South Pacific, Suva (Fiji)

    2010-09-15

    In this study, hybrid fuels consisting of coconut oil, aqueous ethanol and a surfactant (butan-1-ol) were prepared and tested as a fuel in a direct injection diesel engine. After determining fuel properties such as the density, viscosity and gross calorific values of these fuels, they were used to run a diesel engine. The engine performance and exhaust emissions were investigated and compared with that of diesel. The experimental results show that the efficiency of the hybrid fuels is comparable to that of diesel. As the viscosity of the hybrid fuels decreased and approached that of diesel, the efficiency increased progressively towards that of diesel. The exhaust emissions were lower than those for diesel, except carbon monoxide emissions, which increased. Hence, it is concluded that these hybrid fuels can be used successfully as an alternative fuel in diesel engines without any modifications. Their completely renewable nature ensures that they are environmentally friendly with regard to their emissions characteristics. (author)

  8. Highly transparent, low-haze, hybrid cellulose nanopaper as electrodes for flexible electronics

    Science.gov (United States)

    Xu, Xuezhu; Zhou, Jian; Jiang, Long; Lubineau, Gilles; Ng, Tienkhee; Ooi, Boon S.; Liao, Hsien-Yu; Shen, Chao; Chen, Long; Zhu, J. Y.

    2016-06-01

    Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are still characterized by high diffuse transmittance and small direct transmittance, resulting in high optical haze of the substrates. In this study, we proposed a simple methodology for large-scale production of high-transparency, low-haze CNP comprising both long cellulose nanofibrils (CNFs) and short cellulose nanocrystals (CNCs). By varying the CNC/CNF ratio in the hybrid CNP, we could tailor its total transmittance, direct transmittance and diffuse transmittance. By increasing the CNC content, the optical haze of the hybrid CNP could be decreased and its transparency could be increased. The direct transmittance and optical haze of the CNP were 75.1% and 10.0%, respectively, greatly improved from the values of previously reported CNP (31.1% and 62.0%, respectively). Transparent, flexible electrodes were fabricated by coating the hybrid CNP with silver nanowires (AgNWs). The electrodes showed a low sheet resistance (minimum 1.2 Ω sq-1) and a high total transmittance (maximum of 82.5%). The electrodes were used to make a light emitting diode (LED) assembly to demonstrate their potential use in flexible displays.Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are

  9. Design and performance criteria for medical electron accelerators

    Science.gov (United States)

    Nunan, Craig S.

    1985-05-01

    A brief comparison is made of the design and performance of early and modern isocentric microwave linear accelerators for radiotherapy. Generally accepted criteria for the design of current machines are presented, along with a rationale for their selection. The current development of international standards for safety and performance of medical electron accelerators is reviewed.

  10. A Comprehensive Performance Analysis of Proactive, Reactive and Hybrid MANETs Routing Protocols

    CERN Document Server

    Pandey, Kavita

    2011-01-01

    A mobile Ad-hoc network (MANET) is a dynamic multi hop wireless network established by a group of nodes in which there is no central administration. Due to mobility of nodes and dynamic network topology, the routing is one of the most important challenges in ad-hoc networks. Several routing algorithms for MANETs have been proposed by the researchers which have been classified into various categories, however, the most prominent categories are proactive, reactive and hybrid. The performance comparison of routing protocols for MANETs has been presented by other researcher also, however, none of these works considers proactive, reactive and hybrid protocols together. In this paper, the performance of proactive (DSDV), reactive (DSR and AODV) and hybrid (ZRP) routing protocols has been compared. The performance differentials are analyzed on the basis of throughput, average delay, routing overhead and number of packets dropped with a variation of number of nodes, pause time and mobility.

  11. Single electron tunneling in large scale nanojunction arrays with bisferrocene-nanoparticle hybrids

    Science.gov (United States)

    Karmakar, Shilpi; Kumar, Susmit; Marzo, Pasquale; Primiceri, Elisabetta; di Corato, Riccardo; Rinaldi, Ross; Cozzi, Pier Giorgio; Bramanti, Alessandro Paolo; Maruccio, Giuseppe

    2012-03-01

    We report on the fabrication and single electron tunneling behaviour of large scale arrays of nanogap electrodes bridged by bisferrocene-gold nanoparticle hybrids (BFc-AuNP). Coulomb staircase was observed in the low temperature current-voltage curves measured on the junctions with asymmetric tunnel barriers. On the other hand, junctions with symmetric tunneling barrier exhibited mere nonlinear current voltage characteristics without discrete staircase. The experimental results agreed well with simulations based on the orthodox theory. The junction resistance showed thermally activated conduction behaviour at higher temperature. The overall voltage and temperature dependent results show that the transport behaviour of the large arrays of single particle devices obtained by a facile optical lithography and chemical etching process corresponds with the behaviour of single particle devices fabricated by other techniques like e-beam lithography and mechanical breaking methods.We report on the fabrication and single electron tunneling behaviour of large scale arrays of nanogap electrodes bridged by bisferrocene-gold nanoparticle hybrids (BFc-AuNP). Coulomb staircase was observed in the low temperature current-voltage curves measured on the junctions with asymmetric tunnel barriers. On the other hand, junctions with symmetric tunneling barrier exhibited mere nonlinear current voltage characteristics without discrete staircase. The experimental results agreed well with simulations based on the orthodox theory. The junction resistance showed thermally activated conduction behaviour at higher temperature. The overall voltage and temperature dependent results show that the transport behaviour of the large arrays of single particle devices obtained by a facile optical lithography and chemical etching process corresponds with the behaviour of single particle devices fabricated by other techniques like e-beam lithography and mechanical breaking methods. Electronic supplementary

  12. Contribution of interlayer hybridization to the electronic structure in iron pnictides: a study of EELS and first-principles calculations.

    Science.gov (United States)

    Ma, Chao; Yang, Huaixin; Tian, Huanfang; Shi, Honglong; Wang, Zhiwei; Li, Jianqi

    2013-03-20

    Using electron energy loss spectroscopy (EELS) measurements and first-principles electronic structure calculations, the significant interlayer hybridization between the insulating layers (ReO or Ba) and the conducting FeAs layers was investigated in the layered iron pnictides, which is quite different from the case in the cuprate superconductors. This interlayer hybridization would result in an increase in the bandwidth near the Fermi level and interorbital charge transfer in the Fe 3d orbitals, which subsequently leads to a decrease in the Fe local moment and the modification of the Fermi surface topology. Therefore, a three-dimensional character of the electronic structure due to the interlayer hybridization is expected, as observed in previous experiments. These findings indicate that reduced dimensionality is no longer a necessary condition in the search for high-T(c) superconductors in iron pnictides.

  13. Single-Particle Cryo-EM and 3D Reconstruction of Hybrid Nanoparticles with Electron-Dense Components.

    Science.gov (United States)

    Yu, Guimei; Yan, Rui; Zhang, Chuan; Mao, Chengde; Jiang, Wen

    2015-10-01

    Single-particle cryo-electron microscopy (cryo-EM), accompanied with 3D reconstruction, is a broadly applicable tool for the structural characterization of macromolecules and nanoparticles. Recently, the cryo-EM field has pushed the limits of this technique to higher resolutions and samples of smaller molecular mass, however, some samples still present hurdles to this technique. Hybrid particles with electron-dense components, which have been studied using single-particle cryo-EM yet with limited success in 3D reconstruction due to the interference caused by electron-dense elements, constitute one group of such challenging samples. To process such hybrid particles, a masking method is developed in this work to adaptively remove pixels arising from electron-dense portions in individual projection images while maintaining maximal biomass signals for subsequent 2D alignment, 3D reconstruction, and iterative refinements. As demonstrated by the success in 3D reconstruction of an octahedron DNA/gold hybrid particle, which has been previously published without a 3D reconstruction, the devised strategy that combines adaptive masking and standard single-particle 3D reconstruction approach has overcome the hurdle of electron-dense elements interference, and is generally applicable to cryo-EM structural characterization of most, if not all, hybrid nanomaterials with electron-dense components.

  14. Electronic band structure effects in monolayer, bilayer, and hybrid graphene structures

    Science.gov (United States)

    Puls, Conor

    Since its discovery in 2005, graphene has been the focus of intense theoretical and experimental study owing to its unique two-dimensional band structure and related electronic properties. In this thesis, we explore the electronic properties of graphene structures from several perspectives including the magnetoelectrical transport properties of monolayer graphene, gap engineering and measurements in bilayer graphene, and anomalous quantum oscillation in the monolayer-bilayer graphene hybrids. We also explored the device implications of our findings, and the application of some experimental techniques developed for the graphene work to the study of a complex oxide, Ca3Ru2O7, exhibiting properties of strongly correlated electrons. Graphene's high mobility and ballistic transport over device length scales, make it suitable for numerous applications. However, two big challenges remain in the way: maintaining high mobility in fabricated devices, and engineering a band gap to make graphene compatible with logical electronics and various optical devices. We address the first challenge by experimentally evaluating mobilities in scalable monolayer graphene-based field effect transistors (FETs) and dielectric-covered Hall bars. We find that the mobility is limited in these devices, and is roughly inversely proportional to doping. By considering interaction of graphene's Dirac fermions with local charged impurities at the interface between graphene and the top-gate dielectric, we find that Coulomb scattering is responsible for degraded mobility. Even in the cleanest devices, a band gap is still desirable for electronic applications of graphene. We address this challenge by probing the band structure of bilayer graphene, in which a field-tunable energy band gap has been theoretically proposed. We use planar tunneling spectroscopy of exfoliated bilayer graphene flakes demonstrate both measurement and control of the energy band gap. We find that both the Fermi level and

  15. Electron Identification Performance and First Measurement of $W \\to e + \

    CERN Document Server

    Ueno, Rynichi

    2010-01-01

    The identification of electrons is important for the ATLAS experiment because electrons are present in many interactions of interest produced at the Large Hadron Collider. A deep knowledge of the detector, the electron identification algorithms, and the calibration techniques are crucial in order to accomplish this task. This thesis work presents a Monte Carlo study using electrons from the W —> e + v process to evaluate the performance of the ATLAS electromagnetic calorimeter. A significant number of electrons was produced in the early ATLAS collision runs at centre-of-mass energies of 900 GeV and 7 TeV between November 2009 and April 2010, and their properties are presented. Finally, a first measurement of W —> e + v process with the ATLAS experiment was successfully accomplished with the first C = 1.0 nb_ 1 of data at the 7 TeV collision energy, and the properties of the W candidates are also detailed.

  16. Predicting Hybrid Performances for Quality Traits through Genomic-Assisted Approaches in Central European Wheat

    KAUST Repository

    Liu, Guozheng

    2016-07-06

    Bread-making quality traits are central targets for wheat breeding. The objectives of our study were to (1) examine the presence of major effect QTLs for quality traits in a Central European elite wheat population, (2) explore the optimal strategy for predicting the hybrid performance for wheat quality traits, and (3) investigate the effects of marker density and the composition and size of the training population on the accuracy of prediction of hybrid performance. In total 135 inbred lines of Central European bread wheat (Triticum aestivum L.) and 1,604 hybrids derived from them were evaluated for seven quality traits in up to six environments. The 135 parental lines were genotyped using a 90k single-nucleotide polymorphism array. Genome-wide association mapping initially suggested presence of several quantitative trait loci (QTLs), but cross-validation rather indicated the absence of major effect QTLs for all quality traits except of 1000-kernel weight. Genomic selection substantially outperformed marker-assisted selection in predicting hybrid performance. A resampling study revealed that increasing the effective population size in the estimation set of hybrids is relevant to boost the accuracy of prediction for an unrelated test population.

  17. Predicting Hybrid Performances for Quality Traits through Genomic-Assisted Approaches in Central European Wheat.

    Directory of Open Access Journals (Sweden)

    Guozheng Liu

    Full Text Available Bread-making quality traits are central targets for wheat breeding. The objectives of our study were to (1 examine the presence of major effect QTLs for quality traits in a Central European elite wheat population, (2 explore the optimal strategy for predicting the hybrid performance for wheat quality traits, and (3 investigate the effects of marker density and the composition and size of the training population on the accuracy of prediction of hybrid performance. In total 135 inbred lines of Central European bread wheat (Triticum aestivum L. and 1,604 hybrids derived from them were evaluated for seven quality traits in up to six environments. The 135 parental lines were genotyped using a 90k single-nucleotide polymorphism array. Genome-wide association mapping initially suggested presence of several quantitative trait loci (QTLs, but cross-validation rather indicated the absence of major effect QTLs for all quality traits except of 1000-kernel weight. Genomic selection substantially outperformed marker-assisted selection in predicting hybrid performance. A resampling study revealed that increasing the effective population size in the estimation set of hybrids is relevant to boost the accuracy of prediction for an unrelated test population.

  18. Petascale computation performance of lightweight multiscale cardiac models using hybrid programming models.

    Science.gov (United States)

    Pope, Bernard J; Fitch, Blake G; Pitman, Michael C; Rice, John J; Reumann, Matthias

    2011-01-01

    Future multiscale and multiphysics models must use the power of high performance computing (HPC) systems to enable research into human disease, translational medical science, and treatment. Previously we showed that computationally efficient multiscale models will require the use of sophisticated hybrid programming models, mixing distributed message passing processes (e.g. the message passing interface (MPI)) with multithreading (e.g. OpenMP, POSIX pthreads). The objective of this work is to compare the performance of such hybrid programming models when applied to the simulation of a lightweight multiscale cardiac model. Our results show that the hybrid models do not perform favourably when compared to an implementation using only MPI which is in contrast to our results using complex physiological models. Thus, with regards to lightweight multiscale cardiac models, the user may not need to increase programming complexity by using a hybrid programming approach. However, considering that model complexity will increase as well as the HPC system size in both node count and number of cores per node, it is still foreseeable that we will achieve faster than real time multiscale cardiac simulations on these systems using hybrid programming models.

  19. Subtask 2.13 - Advanced Hybrid Particulate Collector-Fundamental Performance

    Energy Technology Data Exchange (ETDEWEB)

    Stanley Miller

    2007-07-01

    Under the Power Plant Improvement Initiative Program funded by the U.S. Department of Energy, a full-scale Advanced Hybrid{trademark} filter was installed at the Big Stone Plant, with start-up in October 2002. The Advanced Hybrid{trademark} filter was retrofitted into Fields 2-4 of the old Big Stone electrostatic precipitator (ESP). While many aspects of the operation were satisfactory, pressure drop was higher than expected. To achieve acceptable pressure drop and successfully demonstrate the Advanced Hybrid{trademark} filter technology, the first fields of the ESP were also converted into an Advanced Hybrid{trademark} filter in 2005. However, since start-up in June 2005, the first fields have been inoperable for multiple reasons. The fundamental cause of the dysfunctional performance of the first fields was attributed to spacing and alignment problems, which led to excessive sparking and shutdown of the high-voltage power. In spite of attempts to correct the problems, satisfactory performance of the first fields was never achieved. Because of the uncertainties of how to achieve acceptable performance with a new technology, the Big Stone Plant made the decision to convert the entire Advanced Hybrid{trademark} filter housing into a pulse-jet fabric filter.

  20. Performance study of macro-bending EDFA/Raman hybrid optical fiber amplifiers

    Science.gov (United States)

    Mahran, O.

    2015-10-01

    In this paper, we present an analytical study of a (macro-bending EDFA)/Raman hybrid optical amplifier. The bending radius is 4 mm with EDFA length 10 m with forward pump power in the range (100-500 mW) and Raman amplifier length (12-55 km) with backward pump power variations (80-200 mW) is considered in our model. Due to bending loss in EDFA, the gain of hybrid amplifier is increased to ~7 dB more than the normal EDFA/Raman hybrid amplifier and the noise figure is decreased by ~2 dB rather than without macro-bending EDFA/Raman hybrid amplifier. The signal to noise ratio (OSNR) calculations shows a better performance of macro-bending EDFA/Raman hybrid amplifier than without macro-bending one. A flat gain is obtained in the signal wavelength region (1560-1600 nm), which is the L-band. The calculated results for macro-bending case are compared with experimental results of normal case by Lee et al., in the L-band showing an increase in the gain, reduction in the noise figure and more gain flatness at the input signal -20 dBm for macro-bending EDFA/Raman hybrid amplifier.

  1. Donor–acceptor graphene-based hybrid materials facilitating photo-induced electron-transfer reactions

    Directory of Open Access Journals (Sweden)

    Anastasios Stergiou

    2014-09-01

    Full Text Available Graphene research and in particular the topic of chemical functionalization of graphene has exploded in the last decade. The main aim is to increase the solubility and thereby enhance the processability of the material, which is otherwise insoluble and inapplicable for technological applications when stacked in the form of graphite. To this end, initially, graphite was oxidized under harsh conditions to yield exfoliated graphene oxide sheets that are soluble in aqueous media and amenable to chemical modifications due to the presence of carboxylic acid groups at the edges of the lattice. However, it was obvious that the high-defect framework of graphene oxide cannot be readily utilized in applications that are governed by charge-transfer processes, for example, in solar cells. Alternatively, exfoliated graphene has been applied toward the realization of some donor–acceptor hybrid materials with photo- and/or electro-active components. The main body of research regarding obtaining donor–acceptor hybrid materials based on graphene to facilitate charge-transfer phenomena, which is reviewed here, concerns the incorporation of porphyrins and phthalocyanines onto graphene sheets. Through illustrative schemes, the preparation and most importantly the photophysical properties of such graphene-based ensembles will be described. Important parameters, such as the generation of the charge-separated state upon photoexcitation of the organic electron donor, the lifetimes of the charge-separation and charge-recombination as well as the incident-photon-to-current efficiency value for some donor–acceptor graphene-based hybrids, will be discussed.

  2. Highly transparent, low-haze, hybrid cellulose nanopaper as electrodes for flexible electronics

    KAUST Repository

    Xu, Xuezhu

    2016-06-01

    Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are still characterized by high diffuse transmittance and small direct transmittance, resulting in high optical haze of the substrates. In this study, we proposed a simple methodology for large-scale production of high-transparency, low-haze CNP comprising both long cellulose nanofibrils (CNFs) and short cellulose nanocrystals (CNCs). By varying the CNC/CNF ratio in the hybrid CNP, we could tailor its total transmittance, direct transmittance and diffuse transmittance. By increasing the CNC content, the optical haze of the hybrid CNP could be decreased and its transparency could be increased. The direct transmittance and optical haze of the CNP were 75.1% and 10.0%, respectively, greatly improved from the values of previously reported CNP (31.1% and 62.0%, respectively). Transparent, flexible electrodes were fabricated by coating the hybrid CNP with silver nanowires (AgNWs). The electrodes showed a low sheet resistance (minimum 1.2 Ω sq-1) and a high total transmittance (maximum of 82.5%). The electrodes were used to make a light emitting diode (LED) assembly to demonstrate their potential use in flexible displays. © 2016 The Royal Society of Chemistry.

  3. Photodetector performance enhancement using an electron accelerator controlled by light.

    Science.gov (United States)

    Srithanachai, Itsara; Dilla Zainol, Farrah; Ueamanapong, Surada; Niemcharoen, Surasak; Ali, Jalil; Yupapin, Preecha P

    2012-07-20

    A new method of photodetector performance enhancement using an embedded optical accelerator circuit within the photodetector is proposed. The principle of optical tweezer generation using a light pulse within a PANDA ring is also reviewed. By using a modified add-drop optical filter known as a PANDA microring resonator, which is embedded within the photodetector circuit, the device performance can be improved by using an electron injection technique, in which electrons can be trapped by optical tweezers generated by a PANDA ring resonator. Finally, electrons can move faster within the device via the optical waveguide without trapping center in the silicon bulk to the contact, in which the increase in photodetector current is seen. Simulation results obtained have shown that the device's light currents are increased by the order of four, and the switching time is increased by the order of five. This technique can be used for better photodetector performance and other semiconductor applications in the future.

  4. PERFORMANCE EVALUATION OF DSDV IN HYBRID WIRELESS MESH NETWORK

    Directory of Open Access Journals (Sweden)

    V. Lakshmi Praba

    2011-09-01

    Full Text Available Wireless Mesh Network (WMN is a new wireless technology and it has the features of large area network coverage, Internet broadband access, self-healing, self-configuring and self-organizing. Routing is an important research issue in WMN. Many routing protocols are available in WMN. These protocols are divided into two categories proactive (Table Driven and reactive (On-demand protocols. This paper discusses the performance of proactive routing protocol Destination Sequenced Distance Vector (DSDV in WMN by considering the various performance metrics (packet delivery ratio, routing overhead and dropped packets by varying transmission rate and mesh client speed.

  5. Simulation of the performance of a hybrid ventilation system in different climates

    Energy Technology Data Exchange (ETDEWEB)

    Charvat, P.; Jicha, M. [Brno Univ. of Technology, Brno (Czech Republic). Faculty of Mechanical Engineering; Niachou, A.; Santamouris, M. [National and Kapodistrian Univ. of Athens, Athens (Greece)

    2005-07-01

    Four different concepts of hybrid ventilation systems for 4 climates in Europe have been developed within the Framework of the European Union project called Residential Hybrid Ventilation (RESHYVENT). This study involved computational simulations to examine the performance of the hybrid ventilation system for a moderate climate in an urban environment under various climatic conditions. A hybrid ventilation system refers to a ventilation system that uses natural driving forces as long as possible and which switches to mechanical forces when needed. It therefore minimizes energy consumption while maintaining good indoor air quality and thermal comfort for occupants. The RESHYVENT hybrid ventilation system consists of a self-regulating air inlet, DC fan, motorized damper, flow meter, central control unit, carbon dioxide sensors and ductwork. If natural driving forces are not sufficient, the fan engages and its speed adjusts to match the demanded flow rate. This paper presents a case study in which the TRNSYS type 15 software package was used with the TRNFlow air flow network module to simulate natural driving forces such as wind and buoyancy in an apartment building situated in an urban canyon. Results were obtained for a specific geometry, occupancy scheme and other factors. The study showed that the hybrid ventilation system was able to maintain required indoor air quality regardless of weather conditions. As such, it was better than the natural ventilation system and holds promise for use in office and residential buildings. The complexity of hybrid and natural ventilation systems is due to the fact that air flow rates depend greatly on climatic conditions. Therefore, simulations must consider thermal and air flow models. Experiments conducted at a demonstration house in Brno, Czech Republic show that the RESHYVENT hybrid ventilation system could maintain the level of carbon dioxide concentration in rooms below 1200 ppm. refs., 7 tabs., 3 figs.

  6. DESIGN AND THERMAL PERFORMANCE OF THE SOLAR BIOMASS HYBRID DRYER FOR CASHEW DRYING

    Directory of Open Access Journals (Sweden)

    Saravanan Dhanuskodi

    2014-12-01

    Full Text Available Drying of Cashew nut to remove testa is one of the most energy-intensive processes of cashew nut process industry. For this reason a hybrid dryer consisting of a solar flat plate collector, a biomass heater and a drying chamber is designed and fabricated. 40 kg of Cashew nut with initial moisture of 9 % is used in the experiment. The performance test of the dryer is carried out in two modes of operation: hybrid-forced convection and hybrid-natural convection. Drying time and drying efficiency during these two modes of operation are estimated and compared with the sun drying. The system is capable of attaining drying temperature between 50º and 70ºC. In the hybrid forced drying, the required moisture content of 3% is achieved within 7 hours and the average system efficiency is estimated as 5.08%. In the hybrid natural drying, the required moisture content is obtained in 9 hours and the average system efficiency is 3.17%. The fuel consumption during the drying process is 0.5 kg/hr and 0.75 kg/hr for forced mode and natural mode, respectively. The drying process in the hybrid forced mode of operation is twice faster than the sun drying. The dryer can be operated in any climatic conditions: as a solar dryer on normal sunny days, as a biomass dryer at night time and as a hybrid dryer on cloudy days. Based on the experimental study, it is concluded that the developed hybrid dryer is suitable for small scale cashew nut farmers in rural areas of developing countries.

  7. Making hybrid [n]-rotaxanes as supramolecular arrays of molecular electron spin qubits

    Science.gov (United States)

    Fernandez, Antonio; Ferrando-Soria, Jesus; Pineda, Eufemio Moreno; Tuna, Floriana; Vitorica-Yrezabal, Iñigo J.; Knappke, Christiane; Ujma, Jakub; Muryn, Christopher A.; Timco, Grigore A.; Barran, Perdita E.; Ardavan, Arzhang; Winpenny, Richard E. P.

    2016-01-01

    Quantum information processing (QIP) would require that the individual units involved--qubits--communicate to other qubits while retaining their identity. In many ways this resembles the way supramolecular chemistry brings together individual molecules into interlocked structures, where the assembly has one identity but where the individual components are still recognizable. Here a fully modular supramolecular strategy has been to link hybrid organic-inorganic [2]- and [3]-rotaxanes into still larger [4]-, [5]- and [7]-rotaxanes. The ring components are heterometallic octanuclear [Cr7NiF8(O2CtBu)16]- coordination cages and the thread components template the formation of the ring about the organic axle, and are further functionalized to act as a ligand, which leads to large supramolecular arrays of these heterometallic rings. As the rings have been proposed as qubits for QIP, the strategy provides a possible route towards scalable molecular electron spin devices for QIP. Double electron-electron resonance experiments demonstrate inter-qubit interactions suitable for mediating two-qubit quantum logic gates.

  8. Enhancing Intrinsic Stability of Hybrid Perovskite Solar Cell by Strong, yet Balanced, Electronic Coupling

    Science.gov (United States)

    El-Mellouhi, Fedwa; Bentria, El Tayeb; Rashkeev, Sergey N.; Kais, Sabre; Alharbi, Fahhad H.

    2016-07-01

    In the past few years, the meteoric development of hybrid organic–inorganic perovskite solar cells (PSC) astonished the community. The efficiency has already reached the level needed for commercialization; however, the instability hinders its deployment on the market. Here, we report a mechanism to chemically stabilize PSC absorbers. We propose to replace the widely used methylammonium cation (CH3NH3+) by alternative molecular cations allowing an enhanced electronic coupling between the cation and the PbI6 octahedra while maintaining the band gap energy within the suitable range for solar cells. The mechanism exploits establishing a balance between the electronegativity of the materials’ constituents and the resulting ionic electrostatic interactions. The calculations demonstrate the concept of enhancing the electronic coupling, and hence the stability, by exploring the stabilizing features of CH3PH3+, CH3SH2+, and SH3+ cations, among several other possible candidates. Chemical stability enhancement hence results from a strong, yet balanced, electronic coupling between the cation and the halides in the octahedron. This shall unlock the hindering instability problem for PSCs and allow them to hit the market as a serious low-cost competitor to silicon based solar cell technologies.

  9. Enhancing Intrinsic Stability of Hybrid Perovskite Solar Cell by Strong, yet Balanced, Electronic Coupling

    Science.gov (United States)

    El-Mellouhi, Fedwa; Bentria, El Tayeb; Rashkeev, Sergey N.; Kais, Sabre; Alharbi, Fahhad H.

    2016-01-01

    In the past few years, the meteoric development of hybrid organic–inorganic perovskite solar cells (PSC) astonished the community. The efficiency has already reached the level needed for commercialization; however, the instability hinders its deployment on the market. Here, we report a mechanism to chemically stabilize PSC absorbers. We propose to replace the widely used methylammonium cation (CH3NH3+) by alternative molecular cations allowing an enhanced electronic coupling between the cation and the PbI6 octahedra while maintaining the band gap energy within the suitable range for solar cells. The mechanism exploits establishing a balance between the electronegativity of the materials’ constituents and the resulting ionic electrostatic interactions. The calculations demonstrate the concept of enhancing the electronic coupling, and hence the stability, by exploring the stabilizing features of CH3PH3+, CH3SH2+, and SH3+ cations, among several other possible candidates. Chemical stability enhancement hence results from a strong, yet balanced, electronic coupling between the cation and the halides in the octahedron. This shall unlock the hindering instability problem for PSCs and allow them to hit the market as a serious low-cost competitor to silicon based solar cell technologies. PMID:27457130

  10. Design guidelines for use of adhesives in hybrid microcircuits. [for electronic equipment in space applications

    Science.gov (United States)

    Caruso, S. V.; Perkins, K. L.; Licari, J. J.

    1973-01-01

    Although it is generally accepted that the use of adhesives in the assembly of hybrid microcircuits offers advantages over other bonding methods, there currently does not exist a set of guidelines for the selection of adhesives which will insure that hybrid microcircuits assembled with them will meet the long use-life, high-reliability requirements of electronic equipment for space applications. This study was directed to the identification of the properties of electrically insulative adhesives that potentially could cause problems in such an application, and to the development of evaluation tests to quantify these properties and thus form the basis for establishing suitable guidelines and, ultimately, specifications. Bond strength, outgassing after cure, and corrosivity were selected for detailed attention since they are considered to be especially critical. Introductory discussion includes enumeration and brief comments on the properties of adhesives considered to be important for the proposed application, a general review of polymeric types of adhesives, and identification of the major types of adhesives commercially available and specifically designed for microelectronic use. The specific tests developed to evaluate bond strength, outgassing after cure, and corrosivity are discussed in detail, and comparative results obtained for selected adhesives representative of the major types are given.

  11. Power sources for portable electronics and hybrid cars: lithium batteries and fuel cells.

    Science.gov (United States)

    Scrosati, Bruno

    2005-01-01

    The activities in progress in our laboratory for the development of batteries and fuel cells for portable electronics and hybrid car applications are reviewed and discussed. In the case of lithium batteries, the research has been mainly focused on the characterization of new electrode and electrolyte materials. Results related to disordered carbon anodes and improved, solvent-free, as well as gel-type, polymer electrolytes are particularly stressed. It is shown that the use of proper gel electrolytes, in combination with suitable electrode couples, allows the development of new types of safe, reliable, and low-cost lithium ion batteries which appear to be very promising power sources for hybrid vehicles. Some of the technologies proven to be successful in the lithium battery area are readapted for use in fuel cells. In particular, this approach has been followed for the preparation of low-cost and stable protonic membranes to be proposed as an alternative to the expensive, perfluorosulfonic membranes presently used in polymer electrolyte membrane fuel cells (PEMFCs). Copyright 2005 The Japan Chemical Journal Forum and Wiley Periodicals, Inc

  12. High-performance solid-state supercapacitors based on graphene-ZnO hybrid nanocomposites

    Science.gov (United States)

    2013-01-01

    In this paper, we report a facile low-cost synthesis of the graphene-ZnO hybrid nanocomposites for solid-state supercapacitors. Structural analysis revealed a homogeneous distribution of ZnO nanorods that are inserted in graphene nanosheets, forming a sandwiched architecture. The material exhibited a high specific capacitance of 156 F g−1 at a scan rate of 5 mV.s−1. The fabricated solid-state supercapacitor device using these graphene-ZnO hybrid nanocomposites exhibits good supercapacitive performance and long-term cycle stability. The improved supercapacitance property of these materials could be ascribed to the increased conductivity of ZnO and better utilization of graphene. These results demonstrate the potential of the graphene-ZnO hybrid nanocomposites as an electrode in high-performance supercapacitors. PMID:24215772

  13. Performance of a carbon nanotube field emission electron gun

    Science.gov (United States)

    Getty, Stephanie A.; King, Todd T.; Bis, Rachael A.; Jones, Hollis H.; Herrero, Federico; Lynch, Bernard A.; Roman, Patrick; Mahaffy, Paul

    2007-04-01

    A cold cathode field emission electron gun (e-gun) based on a patterned carbon nanotube (CNT) film has been fabricated for use in a miniaturized reflectron time-of-flight mass spectrometer (RTOF MS), with future applications in other charged particle spectrometers, and performance of the CNT e-gun has been evaluated. A thermionic electron gun has also been fabricated and evaluated in parallel and its performance is used as a benchmark in the evaluation of our CNT e-gun. Implications for future improvements and integration into the RTOF MS are discussed.

  14. Performance Evaluation of Hybrid ARQ with Code Combining in Packet-Oriented CDMA System

    Institute of Scientific and Technical Information of China (English)

    CHENQingchun; FANPingzhi

    2004-01-01

    In this paper, an extended SNR (signal to noise ratio) concept is proposed to explicate the contribution of code combining to the performance improvement of hybrid ARQ (Automatic repeat request) over the additive white Gaussian noise channel. By extending the Pursley's SNR analysis to hybrid ARQ with code combining in packet-oriented CDMA (Code division multiple access)system, the extended SNR formula is derived, which describes explicitly the SNR variation of the code symbol involved in code combining. It is revealed that the extended SNR formula includes Pursley's SNR formula as a specialcase. Moreover, it is shown that the effective SNR of the combined symbol is increased by a coefficient, which is proportional to the number of repeated replicas involved in the code combining. Based on the extended SNR formula and the resultant SNR variation, a quasi-analytical approximation method is proposed for the performance evaluation of hybrid ARQ with code combining. The residual error rates, average transmission number together with throughput performance are presented by means of numerical analysis and through simulations. It is validated that the extended SNR formula and the resultant quasi-analytical approximations offer a simplified routine to estimate the performance of hybrid ARQ with code combining, particularly for the applications whose reliability performance with respect to the FEC counterpart system could be numerically calculated or evaluated through simulations.

  15. 3D hybrid simulations with gyrokinetic particle ions and fluid electrons

    Energy Technology Data Exchange (ETDEWEB)

    Belova, E.V.; Park, W.; Fu, G.Y. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Strauss, H.R. [New York Univ., NY (United States); Sugiyama, L.E. [Massachusetts Inst. of Tech., Cambridge, MA (United States)

    1998-12-31

    The previous hybrid MHD/particle model (MH3D-K code) represented energetic ions as gyrokinetic (or drift-kinetic) particles coupled to MHD equations using the pressure or current coupling scheme. A small energetic to bulk ion density ratio was assumed, n{sub h}/n{sub b} {much_lt} 1, allowing the neglect of the energetic ion perpendicular inertia in the momentum equation and the use of MHD Ohm`s law E = {minus}v{sub b} {times} B. A generalization of this model in which all ions are treated as gyrokinetic/drift-kinetic particles and fluid description is used for the electron dynamics is considered in this paper.

  16. Hybrid performance in taro (Colocasia esculenta) in relation to genetic dissimilarity of parents.

    Science.gov (United States)

    Quero-García, José; Letourmy, P; Ivancic, A; Feldmann, P; Courtois, B; Noyer, J L; Lebot, V

    2009-07-01

    Taro (Colocasia esculenta) breeding, as other root crop breeding, is based on the production and evaluation of large numbers of hybrids. The selection of parents is based on their phenotypic value in the absence of information concerning general combining ability (GCA), specific combining ability (SCA), or genetic distances between varieties. By combining data from heritability trials and from genetic diversity studies conducted with AFLP and SSR markers, we aimed at studying the relationship between hybrid vigour and genetic dissimilarity between parents. The traits studied included number of suckers, corm weight, corm dimensions, and dry matter content. Correlation coefficients between hybrid gain and dissimilarity values were calculated. The prediction of hybrid performance based on the mid-parent value was compared to the prediction based on a modified expression that takes into account the genetic relationships between parents. Correlations were all but one positive but not statistically significant for all traits, with the exception of the number of suckers, when using SSR markers for dissimilarity calculations. Accordingly, the genetic dissimilarities in the prediction of hybrid performances did not increase the correlation between predicted and observed hybrid vigour values. However, large differences were observed among the residual means from the regression between predicted and observed values when using AFLP or SSR markers, mainly due to the much higher polymorphism revealed by the latter. Models need to be further adapted to the type of molecular marker used, since their ability to reveal different rates of polymorphism will have a direct incidence on the calculation of genetic dissimilarities between genotypes. Nevertheless, since SSR markers are more polymorphic and more informative than AFLP markers, they should be preferentially used for these studies. Low genetic dissimilarity of parents yielded weak heterosis effects and future studies need to be

  17. Oxidation-resistant hybrid metal oxides/metal nanodots/silver nanowires for high performance flexible transparent heaters

    Science.gov (United States)

    Kim, A.-Young; Kim, Min Kyu; Hudaya, Chairul; Park, Ji Hun; Byun, Dongjin; Lim, Jong Choo; Lee, Joong Kee

    2016-02-01

    Despite its excellent optical, electrical, mechanical, and thermal performances, a silver nanowire (AgNW)-based transparent conducting heater (TCH) still demonstrates several drawbacks such as facile nanowire breakdown on application of a high DC voltage, easy oxidation when exposed to harsh environments, leading to increased surface resistivity, and high resistance among wire junctions causing nonhomogeneous temperature profiles. To overcome these issues, the AgNW was hybridized with other transparent heating materials made of fluorine-doped tin oxide (FTO) thin films and NiCr nanodots (FTO/NiCr/AgNW). The dispersed NiCr nanodots (~50 nm) and FTO thin films (~20 nm) electrically bridge the nanowire junctions leading to a decreased sheet resistance and uniform temperature profiles. The hybrid transparent heater shows excellent optical transmittance (>90%) and high saturation temperature (162 °C) at low applied DC voltage (6 V). Moreover, the FTO/NiCr/AgNW heater exhibits a stable sheet resistance in a hostile environment, hence highlighting the excellent oxidation-resistance of the heating materials. These results indicate that the proposed hybrid transparent heaters could be a promising approach to combat the inherent problems associated with AgNW-based transparent heaters for various functional applications.Despite its excellent optical, electrical, mechanical, and thermal performances, a silver nanowire (AgNW)-based transparent conducting heater (TCH) still demonstrates several drawbacks such as facile nanowire breakdown on application of a high DC voltage, easy oxidation when exposed to harsh environments, leading to increased surface resistivity, and high resistance among wire junctions causing nonhomogeneous temperature profiles. To overcome these issues, the AgNW was hybridized with other transparent heating materials made of fluorine-doped tin oxide (FTO) thin films and NiCr nanodots (FTO/NiCr/AgNW). The dispersed NiCr nanodots (~50 nm) and FTO thin films

  18. COCO 3: hybrid power plant surpasses performance target

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-12-01

    Cogeneration company's third power plant at the Map Ta Phut industrial estate in Thailand is a coal fired circulating fluidized bed boiler linked in a unique steam cycle with the heat recovery units of two gas turbines. These HRUs function as both economiser and reheater. With nearly one year of operation behind it, performance has surpassed expectation for output, efficiency, and emission levels. 4 figs.

  19. Electrical Double-Layer Capacitors in Hybrid Topologies —Assessment and Evaluation of Their Performance

    Directory of Open Access Journals (Sweden)

    Joeri Van Mierlo

    2012-11-01

    Full Text Available PHEVs and BEVs make use of battery cells optimized for high energy rather than for high power. This means that the power abilities of these batteries are limited. In order to enhance their performance, a hybrid Rechargeable Energy Storage System (RESS architecture can be used combining batteries with electrical-double layer capacitors (EDLCs. Such a hybridized architecture can be accomplished using passive or active systems. In this paper, the characteristics of these topologies have been analyzed and compared based on a newly developed hybridization simulation tool for association of lithium-ion batteries and EDLCs. The analysis shows that the beneficial impact of the EDLCs brings about enhanced battery performances in terms of energy efficiency and voltage drops, rather than extension of vehicle range. These issues have been particularly studied for the passive and active hybrid topologies. The classical passive and active topologies being expensive and less beneficial in term of cost, volume and weight, a new hybrid configuration based on the parallel combination of lithium-ion and EDLCs on cell level has been proposed in this article. This topology allows reducing cost, volume, and weight and system complexity in a significant way. Furthermore, a number of experimental setups have illustrated the power of the novel topology in terms of battery capacity increase and power capabilities during charging and discharging. Finally, a unique cycle life test campaign demonstrated that the lifetime of highly optimized lithium-ion batteries can be extended up to 30%–40%.

  20. Shape-controlled fabrication of magnetite silver hybrid nanoparticles with high performance magnetic hyperthermia.

    Science.gov (United States)

    Ding, Qi; Liu, Dongfang; Guo, Dawei; Yang, Fang; Pang, Xingyun; Che, Renchao; Zhou, Naizhen; Xie, Jun; Sun, Jianfei; Huang, Zhihai; Gu, Ning

    2017-04-01

    Superparamagnetic Fe3O4 nanoparticles (NPs)-based hyperthermia is a promising non-invasive approach for cancer therapy. However, the heat transfer efficiency of Fe3O4 NPs is relative low, which hinders their practical clinical applications. Therefore, it is promising to improve the magnetic hyperthermia efficiency by exploring the higher performance magnetic NPs-based hybrid nanostructures. In the current study, it presents a straightforward in situ reduction method for the shape-controlled preparation of magnetite (Fe3O4) silver (Ag) hybrid NPs designed as magnetic hyperthermia heat mediators. The magnetite silver hybrid NPs with core-shell (Fe3O4@Ag) or heteromer (Fe3O4-Ag) structures exhibited a higher biocompatibility with SMMC-7721 cells and L02 cells than the individual Ag NPs. Importantly, in the magnetic hyperthermia, with the exposure to alternating current magnetic field, the Fe3O4@Ag and Fe3O4-Ag hybrid NPs indicated much better tumor suppression effect against SMMC-7721 cells than the individual Fe3O4 NPs in vitro and in vivo. These results demonstrate that the hybridisation of Fe3O4 and Ag NPs could greatly enhance the magnetic hyperthermia efficiency of Fe3O4 NPs. Therefore, the Fe3O4@Ag and Fe3O4-Ag hybrid NPs can be used to be as high performance magnetic hyperthermia mediators based on a simple and effective preparation approach.

  1. Novel lithium titanate-graphene hybrid containing two graphene conductive frameworks for lithium-ion battery with excellent electrochemical performance

    Energy Technology Data Exchange (ETDEWEB)

    Ruiyi, Li; Tengyuan, Chen; Beibei, Sun [School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122 (China); Zaijun, Li [School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122 (China); Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, Wuxi 214122 (China); Zhiquo, Gu; Guangli, Wang; Junkang, Liu [School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122 (China)

    2015-10-15

    Graphical abstract: We developed a new Novel lithium titanate-graphene nanohybrid containing two graphene conductive frameworks. The unique architecture creates fast electron transfer and rapid mass transport of electrolyte. The hybrid electrode provides excellent electrochemical performances for lithium-ion batteries, including high specific capacity, outstanding rate capability and intriguing cycling stability. - Highlights: • We reported a new LTO-graphene nanohybrid containing two graphene conductive frameworks. • One graphene framework greatly improves the electrical conductivity of LTO crystal. • Another graphene framework enhances electrical conductivity of between LTO crystals and electrolyte transport. • The unique architecture creates big tap density, ultrafast electron transfer and rapid mass transport. • The hybrid electrode provides excellent electrochemical performance for lithium-ion batteries. - ABSTRACT: The paper reported the synthesis of lithium titanate(LTO)-graphene hybrid containing two graphene conductive frameworks (G@LTO@G). Tetrabutyl titanate and graphene were dispersed in tertbutanol and heated to reflux state by microwave irradiation. Followed by adding lithium acetate to produce LTO precursor/graphene (p-LTO/G). The resulting p-LTO/G offers homogeneous morphology and ultra small size. All graphene sheets were buried in the spherical agglomerates composed of primitive particles through the second agglomeration. The p-LTO/G was calcined to LTO@graphene (LTO@G). To obtain G@LTO@G, the LTO@G was further hybridized with graphene. The as-prepared G@LTO@G shows well-defined three-dimensional structure and hierarchical porous distribution. Its unique architecture creates big tap density, fast electron transfer and rapid electrolyte transport. As a result, the G@LTO@G provides high specific capacity (175.2 mA h g{sup −1} and 293.5 mA cm{sup −3}), outstanding rate capability (155.7 mAh g{sup −1} at 10C) and intriguing cycling

  2. One-pot preparation of Ni-graphene hybrids with enhanced catalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Guiqiang, E-mail: chengphnu@126.com [College of Information Science and Engineering, Hebei North University, Zhangjiakou 075000, Hebei (China); Wang, Fengli [College of Information Science and Engineering, Hebei North University, Zhangjiakou 075000, Hebei (China); Liu, Fei [Department of Electrical Engineering, Zhangjiakou Vocational College of Technology, Zhangjiakou 075000, Hebei (China); Zhang, Xiao, E-mail: Zhangxiao83690@163.com [College of Information Science and Engineering, Hebei North University, Zhangjiakou 075000, Hebei (China)

    2014-10-15

    Highlights: • Ni-rGO hybrids were synthesized by a microwave-assisted method. • NaBH4 was used as a reducing agent to fabricate Ni-rGO hybrids. • Ni-rGO was used as catalyst for the reduction of p-nitrophenol. • Ni-rGO showed higher catalytic ability than pure Ni nanoparticles. • Ni-rGO showed good recyclability and stability. - Abstract: A facile one-pot method was developed to synthesize magnetic nickel nanoparticles (Ni NPs) decorated on reduced graphene oxide (rGO) with NaHB{sub 4} as a reductant under microwave irradiation. The morphologies and structures of the Ni-rGO hybrids were investigated by electron microscopy, thermal gravimetric analysis, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy and magnetic measurements. The results showed that Ni-rGO hybrids composed of the well-dispersed Ni NPs with an average diameter of 12 nm were successfully prepared. To demonstrate one potential application, the catalytic ability of Ni-rGO was evaluated and it was found that Ni-rGO showed much enhanced catalytic ability, good recyclability and stability toward the catalytic reduction of p-nitrophenol to p-aminophenol. The excellent catalytic activity of Ni-rGO hybrids was due possibly to the synergistic effect of Ni NPs and rGO, including the uniform distribution of Ni NPs onto rGO, enhanced electrons separation and transport, as well as the fast adsorption of p-nitrophenol by rGO.

  3. TOPICAL REVIEW: Optics of high-performance electron microscopes

    Directory of Open Access Journals (Sweden)

    H H Rose

    2008-01-01

    Full Text Available During recent years, the theory of charged particle optics together with advances in fabrication tolerances and experimental techniques has lead to very significant advances in high-performance electron microscopes. Here, we will describe which theoretical tools, inventions and designs have driven this development. We cover the basic theory of higher-order electron optics and of image formation in electron microscopes. This leads to a description of different methods to correct aberrations by multipole fields and to a discussion of the most advanced design that take advantage of these techniques. The theory of electron mirrors is developed and it is shown how this can be used to correct aberrations and to design energy filters. Finally, different types of energy filters are described

  4. Effect of CeO2 Addition on Hybrid Direct Carbon Fuel Cell Performance

    DEFF Research Database (Denmark)

    Ippolito, Davide; Deleebeeck, Lisa; Kammer Hansen, Kent

    2017-01-01

    The effect of CeO2 infiltration into the anode or CeO2 mixed with the carbon-fuel on the performance of a Hybrid Direct Carbon Fuel Cell (HDCFC) was studied through the use of polarization curves and electrochemical impedance spectroscopy. The use CeO2 in both ways helped to increase the cell...

  5. Effect of CeO2 Infiltration on Hybrid Direct Carbon Fuel Cell Performance

    DEFF Research Database (Denmark)

    Ippolito, Davide; Deleebeeck, Lisa; Kammer Hansen, Kent

    2014-01-01

    The effect of CeO2 infiltration into the anode or CeO2 mixed with the carbon-fuel on the performance of a Hybrid Direct Carbon Fuel Cell (HDCFC) was studied through the use of polarization curves and electrochemical impedance spectroscopy. The use CeO2 in both ways helped to increase the cell...

  6. Can Ferroelectric Polarization Explain the High Performance of Hybrid Halide Perovskite Solar Cells?

    NARCIS (Netherlands)

    Sherkar, Tejas; Koster, L. Jan Anton

    2016-01-01

    The power conversion efficiency of photovoltaic cells based on the use of hybrid halide perovskites, CH3NH3PbX3 (X = Cl, Br, I), now exceeds 20%. Recently, it was suggested that this high performance originates from the presence of ferroelectricity in the perovskite, which is hypothesized to lower c

  7. Students' Game Performance Improvements during a Hybrid Sport Education-Step-Game-Approach Volleyball Unit

    Science.gov (United States)

    Araújo, Rui; Mesquita, Isabel; Hastie, Peter; Pereira, Cristiana

    2016-01-01

    The purpose of this study was to examine a hybrid combination of sport education and the step-game-approach (SGA) on students' gameplay performance in volleyball, taking into account their sex and skill-level. Seventeen seventh-grade students (seven girls, 10 boys, average age 11.8) participated in a 25-lesson volleyball season, in which the…

  8. High-performance hybrid pervaporation membranes with superior hydrothermal and acid stability

    NARCIS (Netherlands)

    H.L. Castricum; R. Kreiter; H.M. van Veen; D.H.A. Blank; J.F. Vente; J.E. ten Elshof

    2008-01-01

    A new organic-inorganic hybrid membrane has been prepared with exceptional performance in dewatering applications. The only precursor used in the sol-gel synthesis of the selective layer was organically linked 1,2-bis(triethoxysilyl)ethane (BTESE). The microporous structure of this layer enables sel

  9. Students' Game Performance Improvements during a Hybrid Sport Education-Step-Game-Approach Volleyball Unit

    Science.gov (United States)

    Araújo, Rui; Mesquita, Isabel; Hastie, Peter; Pereira, Cristiana

    2016-01-01

    The purpose of this study was to examine a hybrid combination of sport education and the step-game-approach (SGA) on students' gameplay performance in volleyball, taking into account their sex and skill-level. Seventeen seventh-grade students (seven girls, 10 boys, average age 11.8) participated in a 25-lesson volleyball season, in which the…

  10. Energy performance analysis for a photovoltaic, diesel, battery hybrid power supply system

    CSIR Research Space (South Africa)

    Tazvinga, Henerica

    2010-03-01

    Full Text Available This paper looks at an energy performance analysis for a photovoltaic, diesel, and battery hybrid power supply system. The procedure starts by the identification of the hourly load requirements for a typical target consumer and the concept of load...

  11. Can Ferroelectric Polarization Explain the High Performance of Hybrid Halide Perovskite Solar Cells?

    NARCIS (Netherlands)

    Sherkar, Tejas; Koster, L. Jan Anton

    2016-01-01

    The power conversion efficiency of photovoltaic cells based on the use of hybrid halide perovskites, CH3NH3PbX3 (X = Cl, Br, I), now exceeds 20%. Recently, it was suggested that this high performance originates from the presence of ferroelectricity in the perovskite, which is hypothesized to lower c

  12. Hybrid optical-electrochemical electronic nose system based on Zn-porphyrin and multi-walled carbon nanotube composite.

    Science.gov (United States)

    Kladsomboon, Sumana; Lutz, Mario; Pogfay, Tawee; Puntheeranurak, Theeraporn; Kerdcharoen, Teerakiat

    2012-07-01

    In this work, we have enhanced the capability of an e-nose system based on combined optical and electrochemical transduction within a single gas sensor array. The optical part of this e-nose is based on detection of the absorption changes of light emitted from eight light emitting diodes (LEDs) as measured by a CMOS photo-detector. The electrochemical part works by measuring the change in electrical resistivity of the sensing materials upon contact with the sample vapor. Zinc-5,10,15,20-tetra-phenyl-21H,23H-porphyrin (ZnTPP) and multi-walled carbon nanotube (MWCNT) composite was used as the sensing materials based on its good optoelectronic properties. This sensing layer was characterized by UV-Vis spectroscopy and atomic force microscope and tested with various VOC vapors. Density functional theory (DFT) calculations were performed to investigate the electronic properties and interaction energies between ZnTPP and analyte molecules. It can be clearly seen that this hybrid optical-electrochemical electronic nose system can classify the vapor of different volatile organic compounds.

  13. Analysis of Upper Hybrid Wave Growth Rates From Measured Electron Distributions; An Encounter With the Source of Auroral Roar

    Science.gov (United States)

    Bounds, S. R.; Kletzing, C. A.; Labelle, J. W.; Samara, M.; Yoon, P. H.

    2005-12-01

    In January of 2003, the High Bandwidth Auroral Rocket (HIBAR) passed through two regions of strong upper hybrid wave emission associated with the approximate matching of the upper hybrid frequency to twice the electron cyclotron frequency (fuh = 2 fce) (Samara 2004) These types of emission are believed to be the source of the HF auroral roar often observed by ground based receivers. The current model theorizes that the free space 0-mode waves observed on the ground are produced through mode conversion of strong emission of Z-mode, or upper hybrid waves. The relativistic electron cyclotron maser exhibits significant growth rates for the Z-mode when the local upper hybrid frequency is just below (~1%) twice the electron cyclotron frequency and with the appropriately unstable electron distribution (Yoon 1996, Yoon 1998, Yoon 2000). Though auroral roar is frequently observed from the ground, the source region has rarely been identified in-situ and even more rarely with sufficient bandwidth to analyze the underlying physical processes. Analysis of the electron distributions from HIBAR show good agreement with the theoretical distributions used by Yoon:98. HIBAR encountered three separate regions where fuh ≍ 2 fce, two of these regions include strong upper hybrid emission, while the third is void of upper hybrid wave activity. The measured particle distributions demonstrate that, in the two regions with wave emission, the relativistic electron cyclotron maser instability produces Z mode wave growth rates at least an order of magnitude greater than the electron collision frequency. In the third region without wave emission, the growth rates are much smaller in both amplitude and the extent of occurance. Samara, M., J. LaBelle, C. A. Kletzing, and S. R. Bounds, Rocket observations of structured upper hybrid wave at fuh=2fce, Geophys. Res. Lett., 31, L22804, doi:10.1029/2004GL021043. Yoon, P. H., A. T. Weatherwax, and T. J. Rosenberg, Lower ionospheric cyclotron maser

  14. Electronic and vibrational properties of transition metal-oxides: Comparison of GGA, GGA + U, and hybrid approaches

    Science.gov (United States)

    Pandey, Sumeet C.; Xu, Xu; Williamson, Izaak; Nelson, Eric B.; Li, Lan

    2017-02-01

    We estimate the Hubbard parameters for density-functional-theory (DFT) + U calculations of ZrO2, HfO2, TiO2, and NiO based on calibrating the electronic structure obtained from hybrid functional methods. The electronic density of states is used to assess the parameters and the values thus derived are employed for the full electron and phonon dispersion comparisons. The resulting values account for experimental band gaps and electron correlations that are computationally much less demanding to treat within the simpler DFT + U framework than with the typically more accurate yet expensive hybrid functional methods. Limitations of +U scheme is indicated towards describing TiO2 and HfO2 phase-stability.

  15. Engineering of high performance supercapacitor electrode based on Fe-Ni/Fe{sub 2}O{sub 3}-NiO core/shell hybrid nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Ashutosh K., E-mail: ashuvishen@gmail.com, E-mail: aksingh@bose.res.in; Mandal, Kalyan [Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake City, Kolkata 700098 (India)

    2015-03-14

    The present work reports on fabrication and supercapacitor applications of a core/shell Fe-Ni/Fe{sub 2}O{sub 3}-NiO hybrid nanostructures (HNs) electrode. The core/shell Fe-Ni/Fe{sub 2}O{sub 3}-NiO hybrid nanostructures have been fabricated through a two step method (nanowire fabrication and their controlled oxidation). The 1D hybrid nanostructure consists of highly porous shell layer (redox active materials NiO and Fe{sub 2}O{sub 3}) and the conductive core (FeNi nanowire). Thus, the highly porous shell layer allows facile electrolyte diffusion as well as faster redox reaction kinetics; whereas the conductive FeNi nanowire core provides the proficient express way for electrons to travel to the current collector, which helps in the superior electrochemical performance. The core/shell Fe-Ni/Fe{sub 2}O{sub 3}-NiO hybrid nanostructures electrode based supercapacitor shows very good electrochemical performances in terms of high specific capacitance nearly 1415 F g{sup −1} at a current density of 2.5 A g{sup −1}, excellent cycling stability and rate capability. The high quality electrochemical performance of core/shell hybrid nanostructures electrode shows its potential as an alternative electrode for forthcoming supercapacitor devices.

  16. DISTRIBUTION OF VEGF mRNA IN BREAST CANCER WITH NONRADIOACTIVE IN SITU HYBRIDIZATION AT ELECTRON MICROSCOPIC LEVELS

    Institute of Scientific and Technical Information of China (English)

    王医术; 林; 王心蕊; 李一雷; 吴珊; 张丽红

    2002-01-01

    Object: To localize the mRNA coding for VEGF at Ultrastractural level in human breast cancer by using digoxigenin-labeled cDNA probes. Methods: Nonradio- active in situ hybridization at electron microscopic level was employed to detected VEGF mRNA in breast cancer. Result: Cancer cells and endothelial cell of angiogensis show dark color in experiment sections. No dark color can be found in control sections. Positive hybridization signals showed dark dot and were locatedin various compartments of the breast cancer cell and endothelial cell in experiment section. No labeling was observed in control sections. In experiment sections, the staining appeared concentrated in cytoplasm and nucleus of the breast cancer cell and endothelial cell. Conclusion: Nonradioactive in situ hybridization at electron microscopic level is efficient for direct observation of the target site mRNA of VEGF in the cytoplasm and nucleus.

  17. Envelope Soliton in Multi-ion Plasma and Ion-Ion Hybrid Wave Excited by Energetic Electron Beam

    Institute of Scientific and Technical Information of China (English)

    WANG De-Yu; HUANG Guang-Li

    2001-01-01

    Another envelope soliton event below the H+ gyrofrequency and localized density depletion has been discoveredin the low auroral region (~1760 kin) by the Freja satellite. This envelope soliton has a characteristic frequencyat ~190 Hz, which is also close to the resonance frequency of hydrogen ion-oxygen ion hybrid wave. This event iscorrelated in time with the observations of the sharp increase of the ratio of oxygen ion density to hydrogen andwith the electron energization along the magnetic field. A theoretical model on the ion-ion hybrid wave excitedby an energetic electron beam has also been presented. It is found that the ion-ion hybrid wave is mainly excitedby the Cherenkov instability in the auroral region.

  18. Medipix3 Demonstration and understanding of near ideal detector performance for 60 & 80 keV electrons

    CERN Document Server

    Mir, J A; MacInnes, R; Gough, C; Plackett, R; Shipsey, I; Sawada, H; MacLaren, I; Ballabriga, R; Maneuski, D; O'Shea, V; McGrouther, D; Kirkland, A I

    2016-01-01

    In our article we report first quantitative measurements of imaging performance for the current generation of hybrid pixel detector, Medipix3, as direct electron detector. Utilising beam energies of 60 & 80 keV, measurements of modulation transfer function (MTF) and detective quantum efficiency (DQE) have revealed that, in single pixel mode (SPM), energy threshold values can be chosen to maximize either the MTF or DQE, obtaining values near to, or even exceeding, those for an ideal detector. We have demonstrated that the Medipix3 charge summing mode (CSM) can deliver simultaneous, near ideal values of both MTF and DQE. To understand direct detection performance further we have characterized the detector response to single electron events, building an empirical model which can predict detector MTF and DQE performance based on energy threshold. Exemplifying our findings we demonstrate the Medipix3 imaging performance, recording a fully exposed electron diffraction pattern at 24-bit depth and images in SPM a...

  19. Level-1 Electron and Photon trigger performance in 2016 data

    CERN Document Server

    CMS Collaboration

    2016-01-01

    For the 2016 data-taking, the CMS Level-1 trigger has been significantly upgraded to deal with the higher instantaneous luminosity and average number of pile-up events. The performance of the new Level-1 Electron and Photon trigger achieved in 2016 data are presented here.

  20. Effects of electronic outlining on students’ argumentative writing performance

    NARCIS (Netherlands)

    De Smet, Milou; Broekkamp, Hein; Brand-Gruwel, Saskia; Kirschner, Paul A.

    2011-01-01

    De Smet, M. J. R., Broekkamp, H., Brand-Gruwel, S., & Kirschner, P. A. (2011). Effects of electronic outlining on students’ argumentative writing performance. Journal of Computer Assisted Learning, 27(6), 557-574. doi: 0.1111/j.1365-2729.2011.00418.x

  1. High performance 3D printed electronics using electroless plated copper

    OpenAIRE

    Jin Rong Jian; Taeil Kim; Jae Sung Park; Jiacheng Wang; Woo Soo Kim

    2017-01-01

    This paper presents design and performance validation of 3D printed electronic components, 3D toroidal air-core inductors, fabricated by multi-material based Fused Deposition Modelling (FDM) 3D printing technology and electroless copper plating. Designs of toroidal inductor is investigated with different core shapes and winding numbers; circular and half-circular cores with 10 and 13 turns of windings...

  2. Nitrogen doped TiO2-Cu(x)O core-shell mesoporous spherical hybrids for high-performance dye-sensitized solar cells.

    Science.gov (United States)

    Guo, Enyan; Yin, Longwei

    2015-01-07

    We report on high-performance dye-sensitized solar cells (DSSCs) based on nitrogen doped anatase TiO2-CuxO core-shell mesoporous hybrids synthesized through a facile and controlled combined sol-gel and hydrothermal process in the presence of hexadecylamine as the structure-directing agent. The matching of band edges between CuxO and TiO2 to form a semiconductor heterojunction plays an important role in effective separation of light induced electrons and holes, providing a promising photoanode for DSSCs because of its wide absorption spectrum, high electron injection efficiency, and fast electron transference. DSSCs based on the mesoporous TiO2-CuxO core-shell hybrids show a high short-circuit current density of 9.60 mA cm(-2) and a conversion efficiency of 3.86% under one sun illumination. While DSSCs based on the N-doped mesoporous TiO2-CuxO hybrids exhibit the higher short-circuit current density of 13.24 mA cm(-2) and a conversion efficiency of 4.57% under one sun illumination. In comparison with un-doped TiO2-CuxO hybrids, the doping of nitrogen into the lattice of TiO2 can extend the light absorption in the ultraviolet range to the visible light region and effectively decrease the recombination rate of photo-generated electrons and holes. The presented N-doped mesoporous TiO2-CuxO hybrids as photoanodes could find potential applications for high performance DSSCs.

  3. Hybrid exchange-correlation functional for accurate prediction of the electronic and structural properties of ferroelectric oxides

    OpenAIRE

    D., I. Bilc; R., Orlando; R., Shaltaf; G., M. Rignanese; J., Íñiguez; Ph., Ghosez

    2008-01-01

    Using a linear combination of atomic orbitals approach, we report a systematic comparison of various Density Functional Theory (DFT) and hybrid exchange-correlation functionals for the prediction of the electronic and structural properties of prototypical ferroelectric oxides. It is found that none of the available functionals is able to provide, at the same time, accurate electronic and structural properties of the cubic and tetragonal phases of BaTiO$_3$ and PbTiO$_3$. Some, although not al...

  4. A segmented Hybrid Photon Detector with integrated auto-triggering front-end electronics for a PET scanner

    CERN Document Server

    Chesi, Enrico Guido; Joram, C; Mathot, S; Séguinot, Jacques; Weilhammer, P; Ciocia, F; De Leo, R; Nappi, E; Vilardi, I; Argentieri, A; Corsi, F; Dragone, A; Pasqua, D

    2006-01-01

    We describe the design, fabrication and test results of a segmented Hybrid Photon Detector with integrated auto-triggering front-end electronics. Both the photodetector and its VLSI readout electronics are custom designed and have been tailored to the requirements of a recently proposed novel geometrical concept of a Positron Emission Tomograph. Emphasis is put on the PET specific features of the device. The detector has been fabricated in the photocathode facility at CERN.

  5. Environmental assessment for the electric and hybrid vehicle demonstration project, performance standards and financial incentives

    Energy Technology Data Exchange (ETDEWEB)

    LaBelle, S. J.

    1978-10-01

    The assessment is concerned with the impacts of the demonstration of electric and hybrid vehicles acquired to fulfill certain requirements of the Electric and Hybrid Vehicle Research, Development, and Demonstration Act, PL 94-413 as amended. The financial incentives programs and vehicle performance standards associated with the demonstration are also covered. Not included is an assessment of the long term effects of EHV commercialization and of the research and development program being carried out simultaneously with the demonstration, also in response to PL 94-413. These federal actions will be included in a programmatic environmental assessment scheduled for completion in FY 79.

  6. On the Performance of RF-FSO Links with and without Hybrid ARQ

    KAUST Repository

    Makki, Behrooz

    2016-04-01

    This paper studies the performance of hybrid radiofrequency (RF) and free-space optical (FSO) links assuming perfect channel state information (CSI) at the receiver. Considering the cases with and without hybrid automatic repeat request (HARQ), we derive closed-form expressions for the message decoding probabilities as well as the throughput and the outage probability of the RF-FSO setups. We also evaluate the effect of adaptive power allocation and different channel conditions on the throughput and the outage probability. The results show the efficiency of the RF-FSO links in different conditions.

  7. Research on performance of hybrid organic dyes-sensitized solar cell

    Institute of Scientific and Technical Information of China (English)

    Lei Sun; Weizheng Yuan; Dayong Qiao

    2006-01-01

    The hybrid sensitizer rhodamine B and coumarin or eosin and coumarin is used to sensitize nanocrystalline porous films. Absorption of the nanocrystalline photovoltaic cell (NPC) is improved in visible light. The performance of these cells is more effective than that of cells sensitized only by sensitizer rhodamine B or eosin. In the simulative solar light, cell sensitized by hybrid sensitizer rhodamine B and coumarin can get open circuit voltage (Voc) of 550 mV and short circuit current (Isc) of 0.1375 mA/cm2.

  8. A high performance hybrid battery based on aluminum anode and LiFePO4 cathode.

    Science.gov (United States)

    Sun, Xiao-Guang; Bi, Zhonghe; Liu, Hansan; Fang, Youxing; Bridges, Craig A; Paranthaman, M Parans; Dai, Sheng; Brown, Gilbert M

    2016-01-28

    A novel hybrid battery utilizing an aluminum anode, a LiFePO4 cathode and an acidic ionic liquid electrolyte based on 1-ethyl-3-methylimidazolium chloride (EMImCl) and aluminum trichloride (AlCl3) (EMImCl-AlCl3, 1-1.1 in molar ratio) with or without LiAlCl4 is proposed. The hybrid ion battery delivers an initial high capacity of 160 mA h g(-1) at a current rate of C/5. It also shows good rate capability and cycling performance.

  9. Performance Analysis of Hybrid PV/Diesel Energy System in Western Region of Saudi Arabia

    OpenAIRE

    Makbul A. M. Ramli; Ayong Hiendro; H. R. E. H. Bouchekara

    2014-01-01

    The potential implementation of hybrid photovoltaic (PV)/diesel energy system in western region of Saudi Arabia is analyzed in this paper. The solar radiation intensity considered in this study is in the range of 4.15–7.17 kWh/m2/day. The HOMER software is used to perform the technical and economical analysis of the system. Three different system configurations, namely, stand-alone diesel system, and hybrid PV/diesel system with and without battery storage element, will be evaluated and discu...

  10. High performance flexible ultraviolet photodetectors based on TiO2/graphene hybrid for irradiation monitoring applications

    Science.gov (United States)

    Zhou, Chen; Wang, Xiaohong; Kuang, Xuanlin; Xu, Sixing

    2016-07-01

    This paper reports a novel ultraviolet (UV) photodetector based on a TiO2/graphene hybrid, with high responsivity (0.482 A W-1) at 3 V bias and 330 nm irradiation, which is ~100 times higher than that based on pure TiO2. The collaboration of TiO2 and graphene in the hybrid material contributes to the high performance of the device. To be more specific, graphene provides a large surface area to load sufficient TiO2 nanoparticles, and the generated electrons are instantly collected due to the prominent electrical properties of graphene which can overcome the low quantum efficiency of pristine TiO2 caused by recombination of photo-induced electron-hole pairs. The device was fabricated on a flexible substrate using a facile spraying method that shows the possibility of broadening the future of photodetectors in wearable devices. An on-board interface circuit based on commercial IC components is implemented to collaborate with the photodetector to demonstrate a UV sensing application.

  11. Integrated Solid/Nanoporous Copper/Oxide Hybrid Bulk Electrodes for High-performance Lithium-Ion Batteries

    Science.gov (United States)

    Hou, Chao; Lang, Xing-You; Han, Gao-Feng; Li, Ying-Qi; Zhao, Lei; Wen, Zi; Zhu, Yong-Fu; Zhao, Ming; Li, Jian-Chen; Lian, Jian-She; Jiang, Qing

    2013-01-01

    Nanoarchitectured electroactive materials can boost rates of Li insertion/extraction, showing genuine potential to increase power output of Li-ion batteries. However, electrodes assembled with low-dimensional nanostructured transition metal oxides by conventional approach suffer from dramatic reductions in energy capacities owing to sluggish ion and electron transport kinetics. Here we report that flexible bulk electrodes, made of three-dimensional bicontinuous nanoporous Cu/MnO2 hybrid and seamlessly integrated with Cu solid current collector, substantially optimizes Li storage behavior of the constituent MnO2. As a result of the unique integration of solid/nanoporous hybrid architecture that simultaneously enhances the electron transport of MnO2, facilitates fast ion diffusion and accommodates large volume changes on Li insertion/extraction of MnO2, the supported MnO2 exhibits a stable capacity of as high as ~1100 mA h g−1 for 1000 cycles, and ultrahigh charge/discharge rates. It makes the environmentally friendly and low-cost electrode as a promising anode for high-performance Li-ion battery applications. PMID:24096928

  12. Magnon, phonon, and electron temperature profiles and the spin Seebeck effect in magnetic insulator/normal metal hybrid structures

    NARCIS (Netherlands)

    Schreier, M.; Kamra, A.; Weiler, M.; Xiao, J.; Bauer, G.E.W.; Gross, R.; Goennenwein, S.T.B.

    2013-01-01

    We calculate the phonon, electron, and magnon temperature profiles in yttrium iron garnet/platinum bilayers by diffusive theory with appropriate boundary conditions, in particular taking into account interfacial thermal resistances. Our calculations show that in thin film hybrids, the interface magn

  13. N-type polymers as electron extraction layers in hybrid perovskite solar cells with improved ambient stability

    NARCIS (Netherlands)

    Shao, S.; Chen, Z.; Fang, H. -H.; ten Brink, G. H.; Bartesaghi, D.; Adjokatse, S.; Koster, L. J. A.; Kooi, B. J.; Facchetti, A.; Loi, M. A.

    2016-01-01

    We studied three n-type polymers of the naphthalenediimide-bithiophene family as electron extraction layers (EELs) in hybrid perovskite solar cells. The recombination mechanism in these devices is found to be heavily influenced by the EEL transport properties. The maximum efficiency of the devices u

  14. Scanning electron microscopy and fluorescent in situ hybridization of experimental Brachyspira (Serpulina) pilosicoli infection in growing pigs

    DEFF Research Database (Denmark)

    Jensen, Tim Kåre; Møller, Kristian; Boye, Mette

    2000-01-01

    Two groups of six 8-week-old pigs were challenged with 1X10(9) cfu Brachyspira (Serpulina) pilosicoli or Serpulina intermedia daily for 3 consecutive days to study the pathology of porcine colonic spirochetosis by scanning electron microscopy (SEM) and fluorescent in situ hybridization (FISH...

  15. Hybrid Simulation of Laser-Plasma Interactions and Fast Electron Transport in Inhomogeneous Plasma

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, B I; Kemp, A; Divol, L

    2009-05-27

    A new framework is introduced for kinetic simulation of laser-plasma interactions in an inhomogenous plasma motivated by the goal of performing integrated kinetic simulations of fast-ignition laser fusion. The algorithm addresses the propagation and absorption of an intense electromagnetic wave in an ionized plasma leading to the generation and transport of an energetic electron component. The energetic electrons propagate farther into the plasma to much higher densities where Coulomb collisions become important. The high-density plasma supports an energetic electron current, return currents, self-consistent electric fields associated with maintaining quasi-neutrality, and self-consistent magnetic fields due to the currents. Collisions of the electrons and ions are calculated accurately to track the energetic electrons and model their interactions with the background plasma. Up to a density well above critical density, where the laser electromagnetic field is evanescent, Maxwell's equations are solved with a conventional particle-based, finite-difference scheme. In the higher-density plasma, Maxwell's equations are solved using an Ohm's law neglecting the inertia of the background electrons with the option of omitting the displacement current in Ampere's law. Particle equations of motion with binary collisions are solved for all electrons and ions throughout the system using weighted particles to resolve the density gradient efficiently. The algorithm is analyzed and demonstrated in simulation examples. The simulation scheme introduced here achieves significantly improved efficiencies.

  16. Thermal performances of vertical hybrid PV/T air collector

    Science.gov (United States)

    Tabet, I.; Touafek, K.; Bellel, N.; Khelifa, A.

    2016-11-01

    In this work, numerical analyses and the experimental validation of the thermal behavior of a vertical photovoltaic thermal air collector are investigated. The thermal model is developed using the energy balance equations of the PV/T air collector. Experimental tests are conducted to validate our mathematical model. The tests are performed in the southern Algerian region (Ghardaïa) under clear sky conditions. The prototype of the PV/T air collector is vertically erected and south oriented. The absorber upper plate temperature, glass cover temperature, air temperature in the inlet and outlet of the collector, ambient temperature, wind speed, and solar radiation are measured. The efficiency of the collector increases with increase in mass flow of air, but the increase in mass flow of air reduces the temperature of the system. The increase in efficiency of the PV/T air collector is due to the increase in the number of fins added. In the experiments, the air temperature difference between the inlet and the outlet of the PV/T air collector reaches 10 ° C on November 21, 2014, the interval time is between 10:00 and 14:00, and the temperature of the upper plate reaches 45 ° C at noon. The mathematical model describing the dynamic behavior of the typical PV/T air collector is evaluated by calculating the root mean square error and mean absolute percentage error. A good agreement between the experiment and the simulation results is obtained.

  17. PERFORMANCE EVALUATION METHOD FOR BUSINESS PROCESS OF MACHINERY MANUFACTURER BASED ON DEA/AHP HYBRID MODEL

    Institute of Scientific and Technical Information of China (English)

    WANG Ting; YI Shuping; YANG Yuanzhao

    2007-01-01

    A set of indices for performance evaluation for business processes with multiple inputs and multiple outputs is proposed, which are found in machinery manufacturers. Based on the traditional methods of data envelopment analysis (DEA) and analytical hierarchical process (AHP), a hybrid model called DEA/AHP model is proposed to deal with the evaluation of business process performance. With the proposed method, the DEA is firstly used to develop a pairwise comparison matrix, and then the AHP is applied to evaluate the performance of business process using the pairwise comparison matrix. The significant advantage of this hybrid model is the use of objective data instead of subjective human judgment for performance evaluation. In the case study, a project of business process reengineering (BPR) with a hydraulic machinery manufacturer is used to demonstrate the effectiveness of the DEA/AHP model.

  18. Effect of Different Structural Materials on Neutronic Performance of a Hybrid Reactor

    Science.gov (United States)

    Übeyli, Mustafa; Tel, Eyyüp

    2003-06-01

    Selection of structural material for a fusion-fission (hybrid) reactor is very important by taking into account of neutronic performance of the blanket. Refractory metals and alloys have much higher operating temperatures and neutron wall load (NWL) capabilities than low activation materials (ferritic/martensitic steels, vanadium alloys and SiC/SiC composites) and austenitic stainless steels. In this study, effect of primary candidate refractory alloys, namely, W-5Re, T111, TZM and Nb-1Zr on neutronic performance of the hybrid reactor was investigated. Neutron transport calculations were conducted with the help of SCALE 4.3 System by solving the Boltzmann transport equation with code XSDRNPM. Among the investigated structural materials, tantalum had the worst performance due to the fact that it has higher neutron absorption cross section than others. And W-5Re and TZM having similar results showed the best performance.

  19. Electromagnetic and microwave absorbing performance of ultra-thin Fe attached carbon nanotube hybrid buckypaper

    Science.gov (United States)

    Lu, Shaowei; Zeng, Xianjun; Nie, Peng; Feng, Chunlin; Xiong, Xuhai; Ma, Keming

    2014-03-01

    The ultra-thin Fe attached multi-walled carbon nanotube hybrid buckypaper (Fe/MWCNT hybrid buckypaper) was fabricated by vacuum filtration method with monodispersion solutions of MWCNTs and Fe nanoparticles. The morphology, element composition and magnetic properties of buckypapers were characterized by field-emission scanning electron microscope, X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometer. The complex permittivity and permeability, the reflection loss (RL) properties of buckypapers attached composite were investigated in the frequency range of 12.4-18 GHz. The Fe/MWCNTs hybrid buckypaper attached composite posses much broader absorbing bandwidth and larger reflectivity than those of pure MWCNTs buckypaper attached composite with the same absorbing thickness (dm = 0.1 mm). The best reflectivity below -5 dB is at 14.0-18 GHz, and the minimum value is -14.4 dB at 16.8 GHz. The experimental result indicates that Fe/MWCNTs hybrid buckypaper has potential application in thin thickness and light-weight microwave absorbers.

  20. Spatial noise limited NETD performance of a HgCdTe hybrid focal plane array

    Science.gov (United States)

    Gopal, Vishnu

    1996-04-01

    This paper presents a model for theoretically estimating the residual spatial noise in a direct injection readout hybrid focal plane array (FPA) consisting of photovoltaic detectors. The procedure consists of computing the response of the pixels after taking into account the nonlinearity induced by the transfer function in the hybrid configuration and the estimated r.m.s. response nonuniformity from the known input parameters of the detector and readout arrays. A linear two point nonuniformity compensation algorithm is applied to the computed pixel responses to calculate the residual spatial noise. Signal-to-spatial noise ratio is then used to estimate the spatial noise limited NETD performance of MWIR and LWIR Hg 1- x Cd x Te hybrid FPAs.

  1. Performance of PbO2/activated carbon hybrid supercapacitor with carbon foam substrate

    Institute of Scientific and Technical Information of China (English)

    Wu Zhang; Yao Hui Qu; Li Jun Gao

    2012-01-01

    PbO2/activated carbon (AC) hybrid supercapacitor in H2SO4 with a carbon foam current collector is studied.The PbO2/AC hybrid is designed with electrodeposited PbO2 thin film as positive electrode to match with AC negative electrode.The discharge curve shows capacitive characteristics between 1.88 V and 0.65 V.The hybrid system exhibits excellent energy and powe performance,with specific energy of 43.6 Wh/kg at a power density of 654.2 W/kg.The use of carbon foam current collecto ensures stability of the PbO2 electrode in H2SO4 environment.After 2600 deep cycles at 15 C high rate of charge/discharge,the capacity remains nearly unchanged from its initial value.

  2. A Hybrid Neural Network-Genetic Algorithm Technique for Aircraft Engine Performance Diagnostics

    Science.gov (United States)

    Kobayashi, Takahisa; Simon, Donald L.

    2001-01-01

    In this paper, a model-based diagnostic method, which utilizes Neural Networks and Genetic Algorithms, is investigated. Neural networks are applied to estimate the engine internal health, and Genetic Algorithms are applied for sensor bias detection and estimation. This hybrid approach takes advantage of the nonlinear estimation capability provided by neural networks while improving the robustness to measurement uncertainty through the application of Genetic Algorithms. The hybrid diagnostic technique also has the ability to rank multiple potential solutions for a given set of anomalous sensor measurements in order to reduce false alarms and missed detections. The performance of the hybrid diagnostic technique is evaluated through some case studies derived from a turbofan engine simulation. The results show this approach is promising for reliable diagnostics of aircraft engines.

  3. Practical Switching-Based Hybrid FSO/RF Transmission and Its Performance Analysis

    KAUST Repository

    Usman, Muneer

    2014-10-01

    Hybrid free-space optical (FSO)/radio-frequency (RF) systems have emerged as a promising solution for high-data-rate wireless backhaul. We present and analyze a switching-based transmission scheme for the hybrid FSO/RF system. Specifically, either the FSO or RF link will be active at a certain time instance, with the FSO link enjoying a higher priority. We considered both a single-threshold case and a dual-threshold case for FSO link operation. Analytical expressions have been obtained for the outage probability, average bit error rate, and ergodic capacity for the resulting system. Numerical examples are presented to compare the performance of the hybrid scheme with the FSO-only scenario.

  4. Enhanced photocatalytic performance of TiO2-ZnO hybrid nanostructures

    Science.gov (United States)

    Cheng, Chun; Amini, Abbas; Zhu, Chao; Xu, Zuli; Song, Haisheng; Wang, Ning

    2014-02-01

    We studied the photocatalytic properties of rational designed TiO2-ZnO hybrid nanostructures, which were fabricated by the site-specific deposition of amorphous TiO2 on the tips of ZnO nanorods. Compared with the pure components of ZnO nanorods and amorphous TiO2 nanoparticles, these TiO2-ZnO hybrid nanostructures demonstrated a higher catalytic activity. The strong green emission quenching observed from photoluminescence of TiO2-ZnO hybrid nanostructures implied an enhanced charge transfer/separation process resulting from the novel type II heterostructures with fine interfaces. The catalytic performance of annealing products with different TiO2 phase varied with the annealing temperatures. This is attributed to the combinational changes in Eg of the TiO2 phase, the specific surface area and the quantity of surface hydroxyl groups.

  5. Computationally Probing the Performance of Hybrid, Heterogeneous, and Homogeneous Iridium-Based Catalysts for Water Oxidation

    Energy Technology Data Exchange (ETDEWEB)

    García-Melchor, Max [SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering, Stanford University, Stanford CA (United States); Vilella, Laia [Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST),Tarragona (Spain); Departament de Quimica, Universitat Autonoma de Barcelona, Barcelona (Spain); López, Núria [Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Tarragona (Spain); Vojvodic, Aleksandra [SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, Menlo Park CA (United States)

    2016-04-29

    An attractive strategy to improve the performance of water oxidation catalysts would be to anchor a homogeneous molecular catalyst on a heterogeneous solid surface to create a hybrid catalyst. The idea of this combined system is to take advantage of the individual properties of each of the two catalyst components. We use Density Functional Theory to determine the stability and activity of a model hybrid water oxidation catalyst consisting of a dimeric Ir complex attached on the IrO2(110) surface through two oxygen atoms. We find that homogeneous catalysts can be bound to its matrix oxide without losing significant activity. Hence, designing hybrid systems that benefit from both the high tunability of activity of homogeneous catalysts and the stability of heterogeneous systems seems feasible.

  6. High-performance controllable ambipolar infrared phototransistors based on graphene-quantum dot hybrid

    CERN Document Server

    Wang, Ran; Wang, Haiyang; Song, Xiaoxian; Jin, Lufan; Dai, Haitao; Wu, Sen; Yao, Jianquan

    2014-01-01

    The field effect transistors (FETs) exhibited ultrahigh responsivity (107 A/W) to infrared light with great improvement of mobility in graphene / PbS quantum dot (QD) hybrid. These reported transistors are either unipolar or depletion mode devices. In this paper, we presented and fabricated conveniently-controlled grapheme / PbS QD hybrid FETs. Through the investigation on electric and optoelectronic properties, the ambipolar FETs (normally OFF) can be switched ON by raising gate voltage (VG) up to 3.7 V and -0.8 V in the first and third quadrants. Near these thresholds (VT) each carrier species shows comparable mobility (~ 300 cm2V-1s-1). Photo-responsivity reach ~ 107 A/W near each threshold and it will linearly increases with (VG-VT). These hybrid FETs become strongly competitive candidates for devices in flexible integrated circuits with low cost, large area, low-energy consumption and high performances.

  7. Comparison of the treatment performance of hybrid constructed wetlands treating stormwater runoff.

    Science.gov (United States)

    Choi, J Y; Maniquiz-Redillas, M C; Hong, J S; Lee, S Y; Kim, L H

    2015-01-01

    This study was conducted to compare the treatment performance of two hybrid constructed wetlands (CWs) in treating stormwater runoff. The hybrid CWs were composed of a combination of free water surface (FWS) and horizontal subsurface flow (HSSF) CWs. Based on the results, strong correlation exists between potential runoff impacts and stormwater characteristics; however, the low correlations also suggest that not only the monitored parameters contribute to stormwater event mean concentrations (EMC) of pollutants, but other factors should also be considered as well. In the hydraulic and treatment performance of the hybrid CWs, a small surface area to catchment area (SA/CA) ratio, receiving a high concentration of influent EMC, will find it hard to achieve great removal efficiency; also a large SA/CA ratio, receiving low concentration of influent EMC, will find it hard to achieve great removal efficiency. With this, SA/CA ratio and influent characteristics such as EMC or load should be considered among the design factors of CWs. The performance data of the two CWs were used to consider the most cost-effective design of a hybrid CW. The optimum facility capacity (ratio of total runoff volume to storage volume) that is applicable for a target volume reduction and removal efficiency was provided in this study.

  8. Performance of super hybrid rice cultivars grown under no-tillage and direct seeding

    Directory of Open Access Journals (Sweden)

    Min Huang

    2012-04-01

    Full Text Available Good progress has been made in the super hybrid rice (Oryza sativa L. breeding in China. However, rice yield not only depends on the genetic characteristics but also on the agronomic practices. No-tillage and direct seeding (NTDS is a simplified cultivation technology that greatly simplifies both land preparation and crop establishment. Aiming to determine the grain yield performance of super hybrid rice under NTDS and to identify critical factors that determine grain yield, field experiments were conducted in Nanxian, Hunan Province, China in 2009 and 2010. Two super hybrid cultivars, Liangyoupeijiu and Y-liangyou 1, were grown under conventional tillage and transplanting (CTTP and NTDS. Grain yield, yield components, biomass production, crop growth rate and biomass accumulation during sowing to heading (HD and HD to maturity were measured for each cultivar. There was no difference in grain yield under NTDS and CTTP. However, grain yield differed with cultivar and year. Y-liangyou 1 produced 4 % higher grain yield than Liangyoupeijiu in 2009, whereas in 2010 both cultivars yielded similarly. Grain yields of both cultivars were higher in 2009 than in 2010. Higher grain yield of Y-liangyou 1 in 2009 was associated with higher spikelet filling (spikelet filling percentage and grain weight, which resulted from higher biomass production. Crop growth rate after HD was critical for biomass production by the super hybrid rice. We suggest that increasing the crop growth rate after HD is an effective approach to increase grain yield of super hybrid rice under NTDS.

  9. PV-wind hybrid system performance. A new approach and a case study

    Energy Technology Data Exchange (ETDEWEB)

    Arribas, Luis; Cano, Luis; Cruz, Ignacio [Departamento de Energias Renovables, CIEMAT, Avda. Complutense 22, 28040 Madrid (Spain); Mata, Montserrat; Llobet, Ermen [Ecotecnia, Roc Boronat 78, 08005 Barcelona (Spain)

    2010-01-15

    Until now, there is no internationally accepted guideline for the measurement, data exchange and analysis of PV-Wind Hybrid Systems. As there is a need for such a tool, so as to overcome the barrier that the lack of confidence due to the absence of reliability means for the development of the market of Hybrid Systems, an effort has been made to suggest one tool for PV-Wind Hybrid Systems. The suggested guidelines presented in this work are based on the existing guidelines for PV Systems, as a PV-Wind Hybrid system can be roughly thought of as a PV System to which wind generation has been added. So, the guidelines for PV Systems are valid for the PV-Wind System, and only the part referred to wind generation should be included. This has been the process followed in this work. The proposed method is applied to a case study, the CICLOPS Project, a 5 kW PV, 7.5 kW Wind Hybrid system installed at the Isolated Wind Systems Test Site that CIEMAT owns in CEDER (Soria, Spain). This system has been fully monitored through a year and the results of the monitoring activity, characterizing the long-term performance of the system are shown in this work. (author)

  10. Cooling Performance Characteristics on Mobile Air-Conditioning System for Hybrid Electric Vehicles

    OpenAIRE

    Ho-Seong Lee; Moo-Yeon Lee

    2013-01-01

    This study investigates the cooling performance characteristics of the mobile air-conditioning system using R744 (CO2) for the hybrid electric vehicle as an alternative to both the R-134a and the conventional air-conditioning system. The developed air-conditioning system is operated with an electric driven compressor in the battery driving mode and a belt driven compressor in the engine driving mode. The cooling performance characteristics of the developed system have been analyzed by experim...

  11. Microwave exfoliated graphene oxide/TiO{sub 2} nanowire hybrid for high performance lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Ishtiaque Shuvo, Mohammad Arif; Rodriguez, Gerardo; Karim, Hasanul; Lin, Yirong [Department of Mechanical Engineering, University of Texas at El Paso, El Paso, Texas 79968 (United States); Islam, Md Tariqul; Noveron, Juan C. [Department of Chemistry, University of Texas at El Paso, El Paso, Texas 79968 (United States); Ramabadran, Navaneet [Department of Chemical Engineering, University of California at Santa Barbara, California 93106 (United States)

    2015-09-28

    Lithium ion battery (LIB) is a key solution to the demand of ever-improving, high energy density, clean-alternative energy systems. In LIB, graphite is the most commonly used anode material; however, lithium-ion intercalation in graphite is limited, hindering the battery charge rate and capacity. To date, one of the approaches in LIB performance improvement is by using porous carbon (PC) to replace graphite as anode material. PC's pore structure facilitates ion transport and has been proven to be an excellent anode material candidate in high power density LIBs. In addition, to overcome the limited lithium-ion intercalation obstacle, nanostructured anode assembly has been extensively studied to increase the lithium-ion diffusion rate. Among these approaches, high specific surface area metal oxide nanowires connecting nanostructured carbon materials accumulation have shown promising results for enhanced lithium-ion intercalation. Herein, we demonstrate a hydrothermal approach of growing TiO{sub 2} nanowires (TON) on microwave exfoliated graphene oxide (MEGO) to further improve LIB performance over PC. This MEGO-TON hybrid not only uses the high surface area of MEGO but also increases the specific surface area for electrode–electrolyte interaction. Therefore, this new nanowire/MEGO hybrid anode material enhances both the specific capacity and charge–discharge rate. Scanning electron microscopy and X-ray diffraction were used for materials characterization. Battery analyzer was used for measuring the electrical performance of the battery. The testing results have shown that MEGO-TON hybrid provides up to 80% increment of specific capacity compared to PC anode.

  12. Preparation of a Novel Coal Gangue-Polyacrylamide Hybrid Flocculant and Its Flocculation Performance

    Institute of Scientific and Technical Information of China (English)

    Xiangao Quan; Huiyun Wang

    2014-01-01

    A novel flocculant based on hybrid coal gangue-polyacrylamide (HCGPAM) has been prepared by using modified coal gangue and polyacrylamide. Factors related to the preparation such as reaction time, temperature, concentration of the polymer monomer and ratio of initiators are investigated. The product is characterized by infrared spectra (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), aswell as viscometry. The flocculating tests on oilfield drilling wastewater show that the removal efficiency is 85.5% and the light transmittance is 53.6%. The results indicate that the coal gangue could be used for the preparation of inorganic-organic hybrid flocculant and the removal efficiency is much higher than that of commercial polyacrylamide (PAM) or PAM/ coal gangue blend.

  13. Effect of buoyancy and power design parameters on hybrid airship performance

    Science.gov (United States)

    Talbot, P. D.; Gelhausen, P. A.

    1983-01-01

    The effects of several design parameters on the performance of hybrid airships having rotors and propellers were examined with a simple mathematical model. The parameters included buoyancy ratio, Froude number, ratio of rotor power to total power, and rotor shaft tilt. Performance variations resulting from changes in these parameters were calculated, and are presented and discussed. Performance quantities included best climb rate, equivalent vehicle L/D, and maximum speed. Performance at all speeds between hover and maximum speed was found to be sensitive to power distribution between rotors and propellers, and to rotor shaft tilt.

  14. High performance technique for database applicationsusing a hybrid GPU/CPU platform

    KAUST Repository

    Zidan, Mohammed A.

    2012-07-28

    Many database applications, such as sequence comparing, sequence searching, and sequence matching, etc, process large database sequences. we introduce a novel and efficient technique to improve the performance of database applica- tions by using a Hybrid GPU/CPU platform. In particular, our technique solves the problem of the low efficiency result- ing from running short-length sequences in a database on a GPU. To verify our technique, we applied it to the widely used Smith-Waterman algorithm. The experimental results show that our Hybrid GPU/CPU technique improves the average performance by a factor of 2.2, and improves the peak performance by a factor of 2.8 when compared to earlier implementations. Copyright © 2011 by ASME.

  15. Performance analysis and code recognition for dual N-ary orthogonal hybrid modulation systems

    Institute of Scientific and Technical Information of China (English)

    Qiao Xiaoqiang; Zhao Hangsheng; Cai Yueming

    2008-01-01

    A dual N-ary orthogonal hybrid modulation system is introduced in this paper, which can increase the data rate greatly compared with conventional N-ary orthogonal spread spectrum system, so it can be used for high rate data communication. Then, three code recognition algorithms are presented for dual N-ary orthogonal hybrid modulation system and the analytic bit error rate (BER) performance of the system in additive white Gaussian noise (AWGN) and flat Rayleigh fading channel is derived. Finally, the computer simulation of the system with three code recognition algorithms is performed, which shows that the simplified maximum a posteriori (MAP) algorithm is the best for the system with a compromise between the performance and the complexity.

  16. Performance Comparison of different hybrid amplifiers for different numbers of channels

    Directory of Open Access Journals (Sweden)

    Sameksha Bhaskar

    2011-08-01

    Full Text Available We have investigated the performance comparison of different hybrid optical amplifiers (RAMAN-EDFA,RAMAN-SOA,SOA-EDFA,EDFA-RAMAN-EDFA.The proposed configuration consists of 16, 32 and 64 Gbps channels at speed of 10 Gbps. We have realized the different hybrid amplifiers and their parameters like quality factor, ber, eye opening and jitter at different number of channels. The different combinations can provide a better result and better feasibility for long distance transmission. It is observed that SOA-EDFA showed good performance as it can travel max distance of 220,240,260 km at 16, 32 and 64 channels respectively. Also, RAMAN-EDFA showed a good performance as it has a high QUALITY FACTOR (24.27 and BER (1 X 10-40 at 16 channels.

  17. Performance Analysis of Hybrid Distribution in Human-Centric Multimedia Networking

    Institute of Scientific and Technical Information of China (English)

    HU Yuxiang; DONG Fang; LAN Julong

    2016-01-01

    With the booming of Human-centric mul-timedia networking (HMN), there are rising amount of human-made multimedia that needs to distribute to con-sumers with higher speed and efficiency. Hybrid distribu-tion of Client/Server (C/S) and Peer-to-Peer (P2P) have been successfully deployed on the Internet and the practi-cal benefits have been widely reported, while its theoretical performance remains unknown for mass data delivery un-fortunately. This paper presents an analytical and experi-mental study on the performance of accelerating large-scale hybrid distribution over the Internet. In particular, this pa-per focuses on the user behavior in HMN and establishes a user behavior model based on the Kermack-McKendrick model in epidemiology. Analytical expressions of average delay in HMN are then derived based on C/S, P2P and hy-brid distribution, respectively. Our simulation shows how to design and deploy a hybrid distribution system of HMN that helps to bridge the gap between system ultilization and quality of service, which provides direct guidance for practical system design.

  18. Relationship Between Hybrid Performance and Genetic Diversity Based on SSRs and ISSRs in Brassica napus L.

    Institute of Scientific and Technical Information of China (English)

    SHEN Jin-xiong; FU Ting-dong; YANG Guang-sheng

    2003-01-01

    To investigate the relationship between genetic distance (GD) and hybrid performance, twotypes of molecular markers, microsatellites (simple sequence repeats, SSRs) and intro-simple sequence repeats(ISSRs), were employed to detect the genetic diversity of 3 double low self-incompatible lines and 22 male pa-rental varieties of Brassica napus from different geographical origins. Hybrids were produced in a NC Ⅱ mat-ing design by hand-pollination. The result indicated that 25 parental varieties (lines) could be divided into sixgroups by Un-weighted Pair Group Mathematics Average (UPGMA) clustering based on GDs. SI-1300 and SI-1320 could be singly clustered into one group, respectively. Varieties from China could be separated into an-other group, SI-1310 and varieties from foreign countries could be separated into other three groups. Thegrouping was generally consistent with parental pedigrees and geographical origins. Significant differences inyield, quality and phenological period traits were observed among these parent groups. Although hybrid yield/plant showed significantly positive correlation with genetic distance based on SSR and ISSR markers, but thedetermination coefficient was iow. It appeared to be unsuitable for using the genetic distance based on SSR andISSR markers to predict heterosis and hybrid performance in Brassica napus.

  19. Enhanced dielectric performance in polymer composite films with carbon nanotube-reduced graphene oxide hybrid filler.

    Science.gov (United States)

    Kim, Jin-Young; Kim, TaeYoung; Suk, Ji Won; Chou, Harry; Jang, Ji-Hoon; Lee, Jong Ho; Kholmanov, Iskandar N; Akinwande, Deji; Ruoff, Rodney S

    2014-08-27

    The electrical conductivity and the specific surface area of conductive fillers in conductor-insulator composite films can drastically improve the dielectric performance of those films through changing their polarization density by interfacial polarization. We have made a polymer composite film with a hybrid conductive filler material made of carbon nanotubes grown onto reduced graphene oxide platelets (rG-O/CNT). We report the effect of the rG-O/CNT hybrid filler on the dielectric performance of the composite film. The composite film had a dielectric constant of 32 with a dielectric loss of 0.051 at 0.062 wt% rG-O/CNT filler and 100 Hz, while the neat polymer film gave a dielectric constant of 15 with a dielectric loss of 0.036. This is attributed to the increased electrical conductivity and specific surface area of the rG-O/CNT hybrid filler, which results in an increase in interfacial polarization density between the hybrid filler and the polymer.

  20. Performance analysis on a hybrid air-conditioning system of a green building

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Q.; Wang, R.Z.; Dai, Y.J.; Zhai, X.Q. [Shanghai Jiao Tong University (China). School of Mechanical Engineering

    2006-05-15

    This paper presents the performance analysis on a hybrid air-conditioning system according to the hybrid building energy system of the green building demonstration project in Shanghai, in which a 150 m{sup 2} solar collector is used to power two 10 kW adsorption chillers, a vapor compression heat pump is used to cool air in the evaporating end while the condensing heating at about 80{sup o}C is fully used to regenerate a liquid desiccant dehumidification system. In the hybrid system, the sensible cooling to the air is treated mainly by solar adsorption cooling and vapor compression cooling, whereas the latent heat is treated by the liquid desiccant dehumidification system with regeneration from the condensing heat of the heat pump. The results show that the performance of this system is 44.5% higher than conventional vapor compression system at a latent load of 30% and this improving can be achieved by 73.8% at a 42% latent load. The optimal ratio of adsorption refrigerating power to total cooling load for this kind of hybrid systems is also studied in this paper. (author)

  1. Au-embedded ZnO/NiO hybrid with excellent electrochemical performance as advanced electrode materials for supercapacitor.

    Science.gov (United States)

    Zheng, Xin; Yan, Xiaoqin; Sun, Yihui; Bai, Zhiming; Zhang, Guangjie; Shen, Yanwei; Liang, Qijie; Zhang, Yue

    2015-02-04

    Here we design a nanostructure by embedding Au nanoparticles into ZnO/NiO core-shell composites as supercapacitors electrodes materials. This optimized hybrid electrodes exhibited an excellent electrochemical performance including a long-term cycling stability and a maximum specific areal capacitance of 4.1 F/cm(2) at a current density of 5 mA/cm(2), which is much higher than that of ZnO/NiO hierarchical materials (0.5 F/cm(2)). Such an enhanced property is attributed to the increased electro-electrolyte interfaces, short electron diffusion pathways and good electrical conductivity. Apart from this, electrons can be temporarily trapped and accumulated at the Fermi level (EF') because of the localized schottky barrier at Au/NiO interface in charge process until fill the gap between ZnO and NiO, so that additional electrons can be released during discharge. These results demonstrate that suitable interface engineering may open up new opportunities in the development of high-performance supercapacitors.

  2. Self-powered textile for wearable electronics by hybridizing fiber-shaped nanogenerators, solar cells, and supercapacitors.

    Science.gov (United States)

    Wen, Zhen; Yeh, Min-Hsin; Guo, Hengyu; Wang, Jie; Zi, Yunlong; Xu, Weidong; Deng, Jianan; Zhu, Lei; Wang, Xin; Hu, Chenguo; Zhu, Liping; Sun, Xuhui; Wang, Zhong Lin

    2016-10-01

    Wearable electronics fabricated on lightweight and flexible substrate are believed to have great potential for portable devices, but their applications are limited by the life span of their batteries. We propose a hybridized self-charging power textile system with the aim of simultaneously collecting outdoor sunshine and random body motion energies and then storing them in an energy storage unit. Both of the harvested energies can be easily converted into electricity by using fiber-shaped dye-sensitized solar cells (for solar energy) and fiber-shaped triboelectric nanogenerators (for random body motion energy) and then further stored as chemical energy in fiber-shaped supercapacitors. Because of the all-fiber-shaped structure of the entire system, our proposed hybridized self-charging textile system can be easily woven into electronic textiles to fabricate smart clothes to sustainably operate mobile or wearable electronics.

  3. Performance evaluation of hybrid VLC using device cost and power over data throughput criteria

    Science.gov (United States)

    Lee, C. C.; Tan, C. S.; Wong, H. Y.; Yahya, M. B.

    2013-09-01

    Visible light communication (VLC) technology has attained its attention in both academic and industry lately. It is determined by the development of light emitting diode (LED) technology for solid-state lighting (SSL).It has great potential to gradually replace radio frequency (RF) wireless technology because it offers unregulated and unlicensed bandwidth to withstand future demand of indoor wireless access to real-time bandwidth-demanding applications. However, it was found to provide intrusive uplink channel that give rise to unpleasant irradiance from the user device which could interfere with the downlink channel of VLC and hence limit mobility to users as a result of small coverage (field of view of VLC).To address this potential problem, a Hybrid VLC system which integrates VLC (for downlink) and RF (for uplink) technology is proposed. It offers a non-intrusive RF back channel that provides high throughput VLC and maintains durability with conventional RF devices. To deploy Hybrid VLC system in the market, it must be energy and cost saving to attain its equivalent economical advantage by comparing to existing architecture that employs fluorescent or LED lights with RF technology. In this paper, performance evaluation on the proposed hybrid system was carried out in terms of device cost and power consumption against data throughput. Based on our simulation, Hybrid VLC system was found to reduce device cost by 3% and power consumption by 68% when compares to fluorescent lights with RF technology. Nevertheless, when it is compared to LED lights with RF technology, our proposed hybrid system is found to achieve device cost saving as high as 47% and reduced power consumption by 49%. Such promising results have demonstrated that Hybrid VLC system is a feasible solution and has paved the way for greater cost saving and energy efficient compares with the current RF architecture even with the increasing requirement of indoor area coverage.

  4. Performance optimization of RoF systems using 120° hybrid coupler for OSSB signal against third order intermodulation

    Science.gov (United States)

    Kumar, Parvin; Sharma, Sanjay Kumar; Singla, Shelly

    2016-10-01

    The performance of radio over fiber (RoF) system with dual drive Mach Zehender modulator has been optimized against third order intermodulation distortion by using 120° hybrid coupler in transmission system. Signal to Noise Distortion ratio (SNDR) has been evaluated and a performance comparison is also drawn for the systems based on 90° and 120° hybrid coupler in both noise and intermodulation distortion dominant environment. The SNDR is efficiently improved by employing 120° hybrid coupler in noise dominant and intermodulation distortion dominant environment. An improvement of 4.86 dB is obtained in the maximum SNDR with 120° hybrid coupler is obtained over at 20 km optical fiber length compared with a 90° hybrid coupler based system. A significant reduction of third order intermodulation power at receiver has also been observed with 120° hybrid coupler.

  5. Organic-inorganic semiconductor hybrid systems. Structure, morphology, and electronic properties

    Energy Technology Data Exchange (ETDEWEB)

    El Helou, Mira

    2012-08-22

    This dissertation addresses the preparation and characterization of hybrid semiconducting systems combining organic with inorganic materials. Characterization methods used included to determine the structure, morphology, and thermal stability comprised X-ray diffraction (XRD), atomic force microscopy (AFM), thermal desorption spectroscopy (TDS), and X-ray photoelectron spectroscopy (XPS). One organic-inorganic semiconducting system was pentacene (C{sub 22}H{sub 14}) and zinc oxide. This interface was investigated in detail for pentacene on an oxygen-terminated zinc oxide surface, i.e. ZnO(000 anti 1). An extended study on the promising p-n junction was carried out for pentacene on ZnO with different orientations which exhibit different chemical and structural characteristics: ZnO(000 anti 1), ZnO(0001), and ZnO(10 anti 10). Moreover, the organic crystal structure of pentacene was selectively tuned by carefully choosing the substrate temperature. This defined interface with a physisorbed pentacene layer on ZnO was characterized by optical absorption which depends on the temperature of the measured system, the pentacene film thickness, and the molecular orientation and packing. The high quality of the pentacene films allowed in one case to characterize the Davydov splitting by linear polarized light focused on a single crystallite. Another subject in the field of organic-inorganic hybrid materials comprised conjugated dithiols used as self-assembled monolayers (SAMs) for immobilizing semiconducting CdS nanoparticles (NPs) on Au substrates. It was demonstrated that an appropriate selection and preparation of the conjugated SAMs is crucial for building up a light-addressable potentiometric sensor with a sufficient efficiency. An optimized electron transfer was achieved with SAMs of long range ordering, high stability, and adequate conductivity. This was examined for different linkers and was best for stilbenedithiol immobilized in solution at higher temperatures. Due

  6. Photovoltaic performance of dye-sensitized solar cells fabricated with polyvinylidene fluoride–polyacrylonitrile–silicondioxide hybrid composite membrane

    Energy Technology Data Exchange (ETDEWEB)

    Sethupathy, Malaisamy; Pandey, Priyanka; Manisankar, Paramasivam, E-mail: pms11@rediffmail.com

    2014-02-14

    Electrospun fibrous membranes of hybrid composites of polyvinylidene fluoride (PVdF), polyacrylonitrile (PAN) and silicon dioxide (SiO{sub 2}) (PVdF–PAN–SiO{sub 2}) are prepared with different proportions of SiO{sub 2} (3, 5 and 7% w/w). The field emission scanning electron microscopy (FE-SEM) reveals that these membranes have three-dimensional, fully interconnected network structures, which are combined with micropores of fine SiO{sub 2} distribution. The surface roughness of the membranes increases with increasing the SiO{sub 2} content. It is found that 7 wt% SiO{sub 2}/PVdF–PAN electrolyte membrane has the highest ionic conductivity (6.96 × 10{sup −2} S cm{sup −1}) due to the large liquid electrolyte uptake (about 570%). As the concentration of SiO{sub 2} nanoparticles increase, the contact angle value also increases, ranging from 135.70° to 140.60° which indicates that the membrane has higher hydrophobicity. The dye sensitized solar cells (DSSCs) are fabricated using the hybrid composite membrane with PVdF–PAN with 7 wt % SiO{sub 2}. Its photovoltaic performance exhibits an open circuit voltage (V{sub oc}) of 0.79 V and a short circuit current 11.6 mA cm{sup −2} at an incident light intensity of 100 mW cm{sup −2}, producing an efficiency of 5.61%. DSSC, using the hybrid composite electrospun membrane which shows more stable photovoltaic performance than other assembled DSSCs. - Highlights: • Electrospun poly (vinylidine–acrylonitrile) silicon dioxide membrane was prepared. • This membrane has good conductivity, porosity and electrolyte uptake. • It has higher hydrophobicity and interconnected network with plenty of cavities. • DSSCs fabricated with polymer electrolyte exhibited good photovoltaic efficiency.

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

    Science.gov (United States)

    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

  8. Hybrid Effect Evaluation of Steel Fiber and Carbon Fiber on the Performance of the Fiber Reinforced Concrete

    OpenAIRE

    Weimin Song; Jian Yin

    2016-01-01

    Fiber reinforcement is an important method to enhance the performance of concrete. In this study, the compressive test and impact test were conducted, and then the hybrid effect between steel fiber (SF) and carbon fiber (CF) was evaluated by employing the hybrid effect index. Compressive toughness and impact toughness of steel fiber reinforced concrete (SFRC), carbon fiber reinforced concrete (CFRC) and hybrid fiber reinforced concrete (HFRC) were explored at steel fiber volume fraction 0.5%,...

  9. Performance of a Y-Ba-Cu-O superconducting filter/GaAs low noise amplifier hybrid circuit

    Science.gov (United States)

    Bhasin, Kul B.; Toncich, S. S.; Chorey, C. M.; Bonetti, R. R.; Williams, A. E.

    1992-01-01

    A superconducting 7.3 GHz two-pole microstrip bandpass filter and a GaAs low noise amplifier (LNA) were combined into a hybrid circuit and characterized at liquid nitrogen temperatures. This superconducting/seismology circuit's performance was compared to a gold filter/GaAs LNA hybrid circuit. The superconducting filter/GaAs LNA hybrid circuit showed higher gain and lower noise figure than its gold counterpart.

  10. Performance of hybrid programming models for multiscale cardiac simulations: preparing for petascale computation.

    Science.gov (United States)

    Pope, Bernard J; Fitch, Blake G; Pitman, Michael C; Rice, John J; Reumann, Matthias

    2011-10-01

    Future multiscale and multiphysics models that support research into human disease, translational medical science, and treatment can utilize the power of high-performance computing (HPC) systems. We anticipate that computationally efficient multiscale models will require the use of sophisticated hybrid programming models, mixing distributed message-passing processes [e.g., the message-passing interface (MPI)] with multithreading (e.g., OpenMP, Pthreads). The objective of this study is to compare the performance of such hybrid programming models when applied to the simulation of a realistic physiological multiscale model of the heart. Our results show that the hybrid models perform favorably when compared to an implementation using only the MPI and, furthermore, that OpenMP in combination with the MPI provides a satisfactory compromise between performance and code complexity. Having the ability to use threads within MPI processes enables the sophisticated use of all processor cores for both computation and communication phases. Considering that HPC systems in 2012 will have two orders of magnitude more cores than what was used in this study, we believe that faster than real-time multiscale cardiac simulations can be achieved on these systems.

  11. Performance Analysis of a Hybrid Overset Multi-Block Application on Multiple Architectures

    Science.gov (United States)

    Djomehri, M. Jahed; Biswas, Rupak

    2003-01-01

    This paper presents a detailed performance analysis of a multi-block overset grid compu- tational fluid dynamics app!ication on multiple state-of-the-art computer architectures. The application is implemented using a hybrid MPI+OpenMP programming paradigm that exploits both coarse and fine-grain parallelism; the former via MPI message passing and the latter via OpenMP directives. The hybrid model also extends the applicability of multi-block programs to large clusters of SNIP nodes by overcoming the restriction that the number of processors be less than the number of grid blocks. A key kernel of the application, namely the LU-SGS linear solver, had to be modified to enhance the performance of the hybrid approach on the target machines. Investigations were conducted on cacheless Cray SX6 vector processors, cache-based IBM Power3 and Power4 architectures, and single system image SGI Origin3000 platforms. Overall results for complex vortex dynamics simulations demonstrate that the SX6 achieves the highest performance and outperforms the RISC-based architectures; however, the best scaling performance was achieved on the Power3.

  12. Solving Human Performance Problems with Computers. A Case Study: Building an Electronic Performance Support System.

    Science.gov (United States)

    Raybould, Barry

    1990-01-01

    Describes the design of an electronic performance support system (PSS) that was developed to help sales and support personnel access relevant information needed for good job performance. Highlights include expert systems, databases, interactive video discs, formatting information online, information retrieval techniques, HyperCard, computer-based…

  13. Graphene/MoS2 hybrid technology for large-scale two-dimensional electronics.

    Science.gov (United States)

    Yu, Lili; Lee, Yi-Hsien; Ling, Xi; Santos, Elton J G; Shin, Yong Cheol; Lin, Yuxuan; Dubey, Madan; Kaxiras, Efthimios; Kong, Jing; Wang, Han; Palacios, Tomás

    2014-06-11

    Two-dimensional (2D) materials have generated great interest in the past few years as a new toolbox for electronics. This family of materials includes, among others, metallic graphene, semiconducting transition metal dichalcogenides (such as MoS2), and insulating boron nitride. These materials and their heterostructures offer excellent mechanical flexibility, optical transparency, and favorable transport properties for realizing electronic, sensing, and optical systems on arbitrary surfaces. In this paper, we demonstrate a novel technology for constructing large-scale electronic systems based on graphene/molybdenum disulfide (MoS2) heterostructures grown by chemical vapor deposition. We have fabricated high-performance devices and circuits based on this heterostructure, where MoS2 is used as the transistor channel and graphene as contact electrodes and circuit interconnects. We provide a systematic comparison of the graphene/MoS2 heterojunction contact to more traditional MoS2-metal junctions, as well as a theoretical investigation, using density functional theory, of the origin of the Schottky barrier height. The tunability of the graphene work function with electrostatic doping significantly improves the ohmic contact to MoS2. These high-performance large-scale devices and circuits based on this 2D heterostructure pave the way for practical flexible transparent electronics.

  14. Hybrid Direct Carbon Fuel Cell Performance with Anode Current Collector Material

    DEFF Research Database (Denmark)

    Deleebeeck, Lisa; Kammer Hansen, Kent

    2015-01-01

    The influence of the current collector on the performance of a hybrid direct carbon fuel cell (HDCFC), consisting of solid oxide fuel cell (SOFC) with a molten carbonate-carbon slurry in contact with the anode, has been investigated using current-voltage curves. Four different anode current...... collectors were studied: Au, Ni, Ag, and Pt. It was shown that the performance of the direct carbon fuel cell (DCFC) is dependent on the current collector materials, Ni and Pt giving the best performance, due to their catalytic activity. Gold is suggested to be the best material as an inert current collector...

  15. Error rate performance of Hybrid QAM-FSK in OFDM systems exhibiting low PAPR

    Institute of Scientific and Technical Information of China (English)

    LATIF Asma; GOHAR Nasir D.

    2009-01-01

    Multicarrier transmission systems like orthogonal frequency division multiplexing (OFDM) support high data rate and generally require no equalization at the receiver, making them simple and efficient. This paper studies the design and performance analysis of a hybrid modulation system derived from multi-frequency and MQAM signals, employed in OFDM. This modulation scheme has better bit error rate (BER) performance and exhibits low PAPR. The proposed hybrid modulator reduces PAPR while keep-ing the OFDM transceiver design simple, as it does not require any side information or a little side Information (only one bit) to be sent and is efficient for arbitrary number of subcarriers. The results of the implementations are compared with those of conventional OFDM system.

  16. Performance and Stability of Supercapacitor Modules based on Porous Carbon Electrodes in Hybrid Powertrain

    Institute of Scientific and Technical Information of China (English)

    GONG Xuan; XIE Changjun; ZOU Yaohui; QUAN Shuhai; PIOTR Bujlo; SHEN Di

    2014-01-01

    Hybrid power sources have attracted much attention in the electric vehicle area. Particularly, electric-electric hybrid powertrain system consisting of supercapacitor modules and lithium-ion batteries has been widely applied because of the high power density of supercapacitors. In this study, we design a hybrid powertrain system containing two porous carbon electrode-based supercapacitor modules in parallel and one lithium ion battery pack. With the construction of the testing station, the performance and stability of the used supercapacitor modules are investigated in correlation with the structure of the supercapacitor and the nature of the electrode materials applied. It has been shown that the responding time for voltage vibration from 20 V to 48.5 V during charging or discharging process decreases from about 490 s to 94 s with the increase in applied current from 20 A to 100 A. The capacitance of the capacitor modules is nearly independent on the applied current. With the designed setup, the energy efficiency can reach as high as 0.99. The results described here provide a guidance for material selection of supercapacitors and optimized controlling strategy for hybrid power system applied in electric vehicles.

  17. Characterization by fluorescence and electron microscopy in situ hybridization of a double Y isochromosome

    Energy Technology Data Exchange (ETDEWEB)

    Fetni, R.; Lemieux, N.; Richer, C.L. [Universite de Montreal, Quebec (Canada)] [and others

    1996-06-14

    A patient with mixed gonadal dysgenesis and Y isochromosomes I(Y) is described. Lymphocyte cultures from peripheral blood contained a high proportion of 45,X cells and several other cell lines with two different marker chromosomes (mars). These markers had either a monocentric (mar1) or a dicentric appearance (mar2). Following high-resolution GTG, RBG, QFQ, and CBG bandings, five cell lines were identified; 45,X/46,X, + mar1/46,X, + mar2/47,X, + mar1x2/47,X + mar2x2. The percentages were 66/6/26/1/1%, respectively. Chromosome banding analyses were insufficient for characterization of the markers. In situ hybridization of specific probes for the Y centromere and its short arm showed, both in fluorescence and electron microscopy (ENT), two different Y rearrangements. Mar1 is an isochromosome for the short arm i(Yp) and mar2 is a dicentric which was shown by EM to be a double isochromosome Yp, inv dup i(Yp). The breakpoint producing mar1 is within the centromere and the one producing mar2 is within one of the short arms of the Y isochromosome. The findings of different cell populations in peripheral blood lymphocytes indicate the postzygotic instability of this i(Yp). 24 refs., 3 figs., 1 tab.

  18. CFD Predictions for Transonic Performance of the ERA Hybrid Wing-Body Configuration

    Science.gov (United States)

    Deere, Karen A.; Luckring, James M.; McMillin, S. Naomi; Flamm, Jeffrey D.; Roman, Dino

    2016-01-01

    A computational study was performed for a Hybrid Wing Body configuration that was focused at transonic cruise performance conditions. In the absence of experimental data, two fully independent computational fluid dynamics analyses were conducted to add confidence to the estimated transonic performance predictions. The primary analysis was performed by Boeing with the structured overset-mesh code OVERFLOW. The secondary analysis was performed by NASA Langley Research Center with the unstructured-mesh code USM3D. Both analyses were performed at full-scale flight conditions and included three configurations customary to drag buildup and interference analysis: a powered complete configuration, the configuration with the nacelle/pylon removed, and the powered nacelle in isolation. The results in this paper are focused primarily on transonic performance up to cruise and through drag rise. Comparisons between the CFD results were very good despite some minor geometric differences in the two analyses.

  19. Localizing Hybridity: The Politics of Place in Contemporary Cuban Rumba Performance

    OpenAIRE

    2010-01-01

    This study examines a range of innovations that have emerged in the performance of the Afro-Cuban music and dance genre rumba during the last three decades. Rumba, which emerged in the mid-nineteenth century within black and racially mixed communities in western Cuba, is a hybrid musical practice that integrates Central- and West African-derived percussion instruments and rhythmic patterns with European melody and Spanish poetic forms. Recent innovations include the creation of fusions with a...

  20. Solving Problems in Various Domains by Hybrid Models of High Performance Computations

    Directory of Open Access Journals (Sweden)

    Yurii Rogozhin

    2014-03-01

    Full Text Available This work presents a hybrid model of high performance computations. The model is based on membrane system (P~system where some membranes may contain quantum device that is triggered by the data entering the membrane. This model is supposed to take advantages of both biomolecular and quantum paradigms and to overcome some of their inherent limitations. The proposed approach is demonstrated through two selected problems: SAT, and image retrieving.

  1. High-Performance, Radiation-Hardened Electronics for Space Environments

    Science.gov (United States)

    Keys, Andrew S.; Watson, Michael D.; Frazier, Donald O.; Adams, James H.; Johnson, Michael A.; Kolawa, Elizabeth A.

    2007-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project endeavors to advance the current state-of-the-art in high-performance, radiation-hardened electronics and processors, ensuring successful performance of space systems required to operate within extreme radiation and temperature environments. Because RHESE is a project within the Exploration Technology Development Program (ETDP), RHESE's primary customers will be the human and robotic missions being developed by NASA's Exploration Systems Mission Directorate (ESMD) in partial fulfillment of the Vision for Space Exploration. Benefits are also anticipated for NASA's science missions to planetary and deep-space destinations. As a technology development effort, RHESE provides a broad-scoped, full spectrum of approaches to environmentally harden space electronics, including new materials, advanced design processes, reconfigurable hardware techniques, and software modeling of the radiation environment. The RHESE sub-project tasks are: SelfReconfigurable Electronics for Extreme Environments, Radiation Effects Predictive Modeling, Radiation Hardened Memory, Single Event Effects (SEE) Immune Reconfigurable Field Programmable Gate Array (FPGA) (SIRF), Radiation Hardening by Software, Radiation Hardened High Performance Processors (HPP), Reconfigurable Computing, Low Temperature Tolerant MEMS by Design, and Silicon-Germanium (SiGe) Integrated Electronics for Extreme Environments. These nine sub-project tasks are managed by technical leads as located across five different NASA field centers, including Ames Research Center, Goddard Space Flight Center, the Jet Propulsion Laboratory, Langley Research Center, and Marshall Space Flight Center. The overall RHESE integrated project management responsibility resides with NASA's Marshall Space Flight Center (MSFC). Initial technology development emphasis within RHESE focuses on the hardening of Field Programmable Gate Arrays (FPGA)s and Field Programmable Analog

  2. High performance hybrid supercapacitors by using para-Benzoquinone ionic liquid redox electrolyte

    Science.gov (United States)

    Navalpotro, Paula; Palma, Jesús; Anderson, Marc; Marcilla, Rebeca

    2016-02-01

    A solution of 0.4M para-Benzoquinone (p-BQ) in the ionic liquid N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (PYR14TFSI) was used as a redox electrolyte in hybrid supercapacitors. Two carbons with very different textural properties, Pica carbon and Vulcan carbon, were used as electrode material. Electrochemical performance of these energy storage systems was investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge (CD). Unlike SCs with pure IL electrolyte, new battery-like features appeared in the CV curves and CD profiles. This electrochemical performance, associated with the faradaic contribution of the redox electrolyte, results in a significant improvement of the electrochemical performance of the hybrid system. For Vulcan carbon with low specific surface area (SBET = 240 m2 g-1), specific capacitance (Cs) and specific real energy (Ereal) values as high as 70 Fg-1 and 10.3 WhKg-1 were obtained at 5 mAcm-2 with hybrid SC operating at 3 V. This represents an increment of 300% in Cs and Ereal with respect to the SC based on pure PYR14TFSI. For high surface area carbon such as Pica (SBET = 2410 m2g-1), the addition of the redox quinone molecule resulted in a moderate enhancement reaching values of 156 Fg-1 and 30 WhKg-1 under the same experimental conditions (36% and 10% increment, respectively).

  3. Technical performance of the Villas Carrousel PV-Wind hybrid systems

    Energy Technology Data Exchange (ETDEWEB)

    Agredano, J.; Munguia, G.; Flores, J. R. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    Fifteen PV-Wind mini Hybrid Systems were installed at the Villas Carrousel Hotel. The first twelve were installed in December 1995. The remainder were installed during January 1997. The energy produced by the systems is used to provide the hotel illumination. Monitoring of the system`s performance has been carried out since 1996. Each system is integrated by a wind generator (Avispa) rated at 500 W, a PV array ranging from 150 to 320 Wp, an electronic control and a battery bank with capacities from 585 up to 780 Ah. The systems operate at 12 VDC and the energy produced is used through 12 V, 13 Watt high efficiency fluorescent lamps. The systems were designed to produce 140-180 Ah/day. During the first months of operation. Some problems arised with the battery voltage measurement. This parameter was formerly measured at the DC bus car of the control board. Some corrosion problems were detected there. This problem caused the undercharging of the battery banks, and in several cases abnormal operation of the wind generators were observed. In general the systems produce the energy demanded by the load. This first experience is helping to promote the Mini Hybrid technology in other applications. This paper presents some results from the system monitoring for the first year of operation that gives a general idea of the system performance. [Espanol] En el Hotel Villas Carrousel se instalaron 15 sistemas hibridos fotovoltaicos-viento. Los primeros doce se instalaron en diciembre de 1995. Los restantes se instalaron durante el mes de enero de 1997. La energia producida por los sistemas se usa para proporcionar la iluminacion del hotel. El monitoreo del rendimiento del sistema se ha llevado a cabo desde 1966. Cada sistema esta integrado por un aerogenerador (Avispa) con capacidad nominal de 500 W, en un arreglo fotovoltaico que varia de 150 a 320 Wp, un control electronico y un banco de baterias con capacidades desde 585 hasta 780 Ampere-horas. Los sistemas operan a 12 VCD y

  4. Improved cider fermentation performance and quality with newly generated Saccharomyces cerevisiae × Saccharomyces eubayanus hybrids.

    Science.gov (United States)

    Magalhães, Frederico; Krogerus, Kristoffer; Vidgren, Virve; Sandell, Mari; Gibson, Brian

    2017-08-01

    Yeast cryotolerance may be advantageous for cider making, where low temperatures are usually employed. Here, we crossed the cryotolerant S. eubayanus with a S. cerevisiae wine strain and assessed the suitability of the hybrids for low-temperature cider fermentation. All strains fermented the juice to 5% ABV, but at different rates; hybrid strains outperformed S. cerevisiae, which was sensitive to low temperatures. The best hybrid fermented similarly to S. eubayanus. S. eubayanus produced sulphurous off flavours which masked a high concentration of fruity ester notes. This phenotype was absent in the hybrid strains, resulting in distinctly fruitier ciders. Aroma was assessed by an independent consumer panel, which rated the hybrid ciders as identical to the wine strain cider. Both were significantly more pleasant than the S. eubayanus cider. Interspecific hybridization can apparently be used effectively to improve low-temperature fermentation performance without compromising product quality.

  5. First Principles Study on the Electronic Structure and Interface Stability of Hybrid Silicene/Fluorosilicene Nanoribbons

    National Research Council Canada - National Science Library

    Jiang, Q G; Zhang, J F; Ao, Z M; Wu, Y P

    2015-01-01

    The interface stability of hybrid silicene/fluorosilicene nanoribbons (SFNRs) has been investigated by using density functional theory calculations, where fluorosilicene is the fully fluorinated silicene...

  6. Formation of porous SnS nanoplate networks from solution and their application in hybrid solar cells† †Electronic supplementary information (ESI) available: Details to performed experiments and characterisation methods, additional XRD data, absorption spectra, TAS data and SEM images. See DOI: 10.1039/c5cc03125g Click here for additional data file.

    Science.gov (United States)

    Gury, L.; Sánchez-Molina, I.; Martínez, L.

    2015-01-01

    Herein, we present a facile solution-based route towards nanostructured, hybrid absorber layers based on tin mono-sulfide (SnS), an emerging, non-toxic absorber material for low-cost and large-scale PV applications. Charge photogeneration properties in the hybrid system are studied using transient absorption spectroscopy and fabricated solar cells show efficient photocurrent generation over a broad spectral range. PMID:26016404

  7. Facile Preparation of Phosphotungstic Acid-Impregnated Yeast Hybrid Microspheres and Their Photocatalytic Performance for Decolorization of Azo Dye

    Directory of Open Access Journals (Sweden)

    Lan Chen

    2013-01-01

    Full Text Available Phosphotungstic acid (HPW-impregnated yeast hybrid microspheres were prepared by impregnation-adsorption technique through tuning pH of the aqueous yeast suspensions. The obtained products were characterized by field emission scanning electron microscopy (FE-SEM, energy dispersive spectrometry (EDS, X-ray diffraction (XRD, thermogravimetry-differential scanning calorimetry (TG-DSC, and ultraviolet-visible spectrophotometry (UV-Vis, respectively. FE-SEM and EDS ascertain that the HPW has been effectively introduced onto the surface of yeast, and the resulting samples retain ellipsoid shape, with the uniform size (length 4.5 ± 0.2 μm, width 3.0 ± 0.3 μm and good monodispersion. XRD pattern indicates that the main crystal structure of as-synthesized HPW@yeast microsphere is Keggin structure. TG-DTA states that the HPW in composites has better thermal stability than pure HPW. Fourier transform infrared spectroscopy (FT-IR elucidates that the functional groups or chemical bonds inherited from the pristine yeast cell were critical to the assembling of the composites. UV-Vis shows that the obtained samples have a good responding to UV light. The settling ability indicates that the hybrid microspheres possess an excellent suspension performance. In the test of catalytic activity, the HPW@yeast microsphere exhibits a high photocatalytic activity for the decoloration of Methylene blue and Congo red dye aqueous solutions, and there are a few activity losses after four cycles of uses.

  8. A Facile Bottom-Up Approach to Construct Hybrid Flexible Cathode Scaffold for High-Performance Lithium-Sulfur Batteries.

    Science.gov (United States)

    Ghosh, Arnab; Manjunatha, Revanasiddappa; Kumar, Rajat; Mitra, Sagar

    2016-12-14

    Lithium-sulfur batteries mostly suffer from the low utilization of sulfur, poor cycle life, and low rate performances. The prime factors that affect the performance are enormous volume change of the electrode, soluble intermediate product formation, poor electronic and ionic conductivity of S, and end discharge products (i.e., Li2S2 and Li2S). The attractive way to mitigate these challenges underlying in the fabrication of a sulfur nanocomposite electrode consisting of different nanoparticles with distinct properties of lithium storage capability, mechanical reinforcement, and ionic as well as electronic conductivity leading to a mechanically robust and mixed conductive (ionic and electronic conductive) sulfur electrode. Herein, we report a novel bottom-up approach to synthesize a unique freestanding, flexible cathode scaffold made of porous reduced graphene oxide, nanosized sulfur, and Mn3O4 nanoparticles, and all are three-dimensionally interconnected to each other by hybrid polyaniline/sodium alginate (PANI-SA) matrix to serve individual purposes. A capacity of 1098 mAh g(-1) is achieved against lithium after 200 cycles at a current rate of 2 A g(-1) with 97.6% of initial capacity at a same current rate, suggesting the extreme stability and cycling performance of such electrode. Interestingly, with the higher current density of 5 A g(-1), the composite electrode exhibited an initial capacity of 1015 mA h g(-1) and retained 71% of the original capacity after 500 cycles. The in situ Raman study confirms the polysulfide absorption capability of Mn3O4. This work provides a new strategy to design a mechanically robust, mixed conductive nanocomposite electrode for high-performance lithium-sulfur batteries and a strategy that can be used to develop flexible large power storage devices.

  9. Layer-by-layer assembled multilayer TiO(x) for efficient electron acceptor in polymer hybrid solar cells.

    Science.gov (United States)

    Kang, Hyunbum; Lee, Chanwoo; Yoon, Sung Cheol; Cho, Chul-Hee; Cho, Jinhan; Kim, Bumjoon J

    2010-11-16

    We demonstrate that TiO(x) nanocomposite films fabricated using electrostatic layer-by-layer (LbL) assembly improve the power conversion efficiency of photovoltaic cells compared to conventional TiO(x) films fabricated via the sol-gel process. For this study, titanium precursor/poly(allylamine hydrochloride) (PAH) multilayer films were first deposited onto indium tin oxide-coated glass to produce TiO(x) nanocomposites (TiO(x)NC). The specific effect of the LbL processed TiO(x) on photovoltaic performance was investigated using the planar bilayer TiO(x)NC and highly regioregular poly(3-hexylthiophene) (P3HT) solar cells, and the P3HT/LbL TiO(x)NC solar cells showed a dramatic increase in power efficiency, particularly in terms of the short current density and fill factor. The improved efficiency of this device is mainly due to the difference in the chemical composition of the LbL TiO(x)NC films, including the much higher Ti(3+)/Ti(4+) ratio and the highly reactive facets of crystals as demonstrated by XPS and XRD measurement, thus enhancing the electron transfer between electron donors and acceptors. In addition, the grazing incidence wide-angle X-ray scattering (GIWAXS) study revealed the presence of more highly oriented P3HT stacks parallel to the substrate on the LbL TiO(x)NC film compared to those on the sol-gel TiO(x) films, possibly influencing the hole mobility of P3HT and the energy transfer near and at the interface between the P3HT and TiO(x) layers. The results of this study demonstrate that this approach is a promising one for the design of hybrid solar cells with improved efficiency.

  10. Electron-Muon Ranger: performance in the MICE Muon Beam

    CERN Document Server

    Adams, D; Vankova-Kirilova, G.; Bertoni, R.; Bonesini, M.; Chignoli, F.; Mazza, R.; Palladino, V.; de Bari, A.; Cecchet, G.; Capponi, M.; Iaciofano, A.; Orestano, D.; Pastore, F.; Tortora, L.; Kuno, Y.; Sakamoto, H.; Ishimoto, S.; Filthaut, F.; Hansen, O.M.; Ramberger, S.; Vretenar, M.; Asfandiyarov, R.; Bene, P.; Blondel, A.; Cadoux, F.; Debieux, S.; Drielsma, F.; Graulich, J.S.; Husi, C.; Karadzhov, Y.; Masciocchi, F.; Nicola, L.; Messomo, E.Noah; Rothenfusser, K.; Sandstrom, R.; Wisting, H.; Charnley, G.; Collomb, N.; Gallagher, A.; Grant, A.; Griffiths, S.; Hartnett, T.; Martlew, B.; Moss, A.; Muir, A.; Mullacrane, I.; Oates, A.; Owens, P.; Stokes, G.; Warburton, P.; White, C.; Adams, D.; Barclay, P.; Bayliss, V.; Bradshaw, T.W.; Courthold, M.; Francis, V.; Fry, L.; Hayler, T.; Hills, M.; Lintern, A.; Macwaters, C.; Nichols, A.; Preece, R.; Ricciardi, S.; Rogers, C.; Stanley, T.; Tarrant, J.; Watson, S.; Wilson, A.; Bayes, R.; Nugent, J.C.; Soler, F.J.P.; Cooke, P.; Gamet, R.; Alekou, A.; Apollonio, M.; Barber, G.; Colling, D.; Dobbs, A.; Dornan, P.; Hunt, C.; Lagrange, J-B.; Long, K.; Martyniak, J.; Middleton, S.; Pasternak, J.; Santos, E.; Savidge, T.; Uchida, M.A.; Blackmore, V.J.; Carlisle, T.; Cobb, J.H.; Lau, W.; Rayner, M.A.; Tunnell, C.D.; Booth, C.N.; Hodgson, P.; Langlands, J.; Nicholson, R.; Overton, E.; Robinson, M.; Smith, P.J.; Dick, A.; Ronald, K.; Speirs, D.; Whyte, C.G.; Young, A.; Boyd, S.; Franchini, P.; Greis, J.; Pidcott, C.; Taylor, I.; Gardener, R.; Kyberd, P.; Littlefield, M.; Nebrensky, J.J.; Bross, A.D.; Fitzpatrick, T.; Leonova, M.; Moretti, A.; Neuffer, D.; Popovic, M.; Rubinov, P.; Rucinski, R.; Roberts, T.J.; Bowring, D.; DeMello, A.; Gourlay, S.; Li, D.; Prestemon, S.; Virostek, S.; Zisman, M.; Hanlet, P.; Kafka, G.; Kaplan, D.M.; Rajaram, D.; Snopok, P.; Torun, Y.; Blot, S.; Kim, Y.K.; Bravar, U.; Onel, Y.; Cremaldi, L.M.; Hart, T.L.; Luo, T.; Sanders, D.A.; Summers, D.J.; Cline, D.; Yang, X.; Coney, L.; Hanson, G.G.; Heidt, C.

    2015-01-01

    The Muon Ionization Cooling Experiment (MICE) will perform a detailed study of ionization cooling to evaluate the feasibility of the technique. To carry out this program, MICE requires an efficient particle-identification (PID) system to identify muons. The Electron-Muon Ranger (EMR) is a fully-active tracking-calorimeter that forms part of the PID system and tags muons that traverse the cooling channel without decaying. The detector is capable of identifying electrons with an efficiency of 98.6%, providing a purity for the MICE beam that exceeds 99.8%. The EMR also proved to be a powerful tool for the reconstruction of muon momenta in the range 100-280 MeV/$c$.

  11. Design Optimization and Performance of a Novel 6-Slot 5-Pole PMFSM with Hybrid Excitation for Hybrid Electric Vehicle

    Science.gov (United States)

    Sulaiman, Erwan; Kosaka, Takashi; Matsui, Nobuyuki

    With growing concerns over our environment, more and more people in automakers, governments and customers think that the electric drive becomes more attractive research. Since electric motors play an important role in both EVs and HEVs, it is a pressing need for researchers to develop advanced electric machines. As one of the candidates, permanent magnet flux switching machine (PMFSM) with additional coil excitation has several attractive features compared to interior permanent magnet synchronous machines (IPMSM) conventionally employed in HEV. The variable flux control capability and robust rotor structure make this machine becoming more attractive to apply for high speed motor drive system coupled with reduction gear. This paper presents an investigation into design possibility of 6-slot 5-pole PMFSM with hybrid excitation for traction drives in HEVs. An improved design is examined to gain a better performance in its maximum torque and power production. The final designed machine enables to keep much power density compared to existing IPMSM installed on the commercial SUV-HEV.

  12. Cu–Li{sub 2}MnSiO{sub 4}-polyaniline composite hybrids as high performance cathode for lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sol-Nip; Baek, Seulgi; Amaresh, Samuthirapandian [Faculty of Applied Chemical Engineering, Chonnam National University, Gwang-ju 500-757 (Korea, Republic of); Aravindan, Vanchiappan [Faculty of Applied Chemical Engineering, Chonnam National University, Gwang-ju 500-757 (Korea, Republic of); Energy Research Institute @ NTU (ERI-N), Nanyang Technological University, Research Techno Plaza, 50 Nanyang Drive, Singapore 637553 (Singapore); Chung, Kyung Yoon; Cho, Byung Won [Center for Energy Convergence, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Yoon, Won-Sub, E-mail: wsyoon@skku.edu [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Lee, Yun-Sung, E-mail: leeys@chonnam.ac.kr [Faculty of Applied Chemical Engineering, Chonnam National University, Gwang-ju 500-757 (Korea, Republic of)

    2015-05-05

    Highlights: • High performance Cu–Li{sub 2}MnSiO{sub 4}-PANI composites hybrids are prepared by Sol–gel. • Beyond one electron reaction is realized for the mentioned composite in half-cell assembly. • Stable cycling profiles are noted upon cycling with ∼63% retention after 50 cycles. - Abstract: We reported the dramatic improvement in electrochemical properties of high capacity orthosilicate, Li{sub 2}MnSiO{sub 4} by conventional sol–gel route. Simple inclusion of metallic Cu and subsequent hybridization with polyaniline (PANI) nanofibers certainly promotes superior electrochemical activity in terms of high reversibility i.e. beyond one electron reaction and cycling stability. First, the Li{sub 2}MnSiO{sub 4} nanoparticles are prepared by adipic acid assisted sol–gel technique at 700 °C under Ar flow by fine tuning the sintering duration. Then, optimization of adipic acid and Cu concentrations are performed based on the mentioned sintering conditions to yield high performance cathode active material. The Cu–Li{sub 2}MnSiO{sub 4}-PANI hybrid exhibits the reversible insertion of ∼1.15 and 0.73 mol of Li for first and 50th cycles, respectively. This corresponds to the ∼63% of retention.

  13. Highly efficient hybrid photovoltaics based on hyperbranched three-dimensional TiO2 electron transporting materials

    KAUST Repository

    Mahmood, Khalid

    2015-03-23

    A 3D hyperbranched TiO2 electron transporting material is demonstrated, which exhibits superior carrier transport and lifetime, as well as excellent infiltration, leading to highly efficient mesostructured hybrid solar cells, such as lead-halide perovskites (15.5%) and dye-sensitized solar cells (11.2%). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. PERFORMANCE ANALYSIS OF AZIMUTH ELECTRONIC BEAM STEERING MODE SPACEBORNE SAR

    Institute of Scientific and Technical Information of China (English)

    Han Xiaodong; Xu Wei; Han Xiaolei

    2013-01-01

    Pointing angle and pattern of the antenna can be changed swiftly to actualize the azimuth beam scanning by using electronic beam steering,which makes the Synthetic Aperture Radar (SAR)system more flexible and achieve a high resolution or cover a long strip within short time span.When the pointing angle is steered away from boresight,some aberrations may appear on the antenna pattern,e.g.,the grating lobe appears,the main lobe gain decrease,and antenna pattern broadens,e.g.,the aberrations result in the worsening of system performance,and complicate the corresponding performance analysis method.Conventional computation methods of performance parameters do not account for the rapid change of the antenna pattern.It introduces remarkable errors when the scanning angle is large.In this paper,a method of calculating performance parameters is proposed for the beam steering mode,which achieves the parameters by the energy accumulation in time domain.Actually,the proposed method simulates the working process of SAR and obtains accurate performance parameters.Furthermore,we analyze the effects of the grating lobe on the Azimuth Ambiguity to Signal Ratio (AASR),and present the generic Pulse Repetition Frequency (PRF) choosing principle which can also prevent the ambiguous area from weighting by the grating lobe.Finally,the effect of the antenna configuration on the performance parameters is analyzed by a system example.

  15. Improved performance of colloidal CdSe quantum dot-sensitized solar cells by hybrid passivation.

    Science.gov (United States)

    Huang, Jing; Xu, Bo; Yuan, Chunze; Chen, Hong; Sun, Junliang; Sun, Licheng; Agren, Hans

    2014-11-12

    A hybrid passivation strategy is employed to modify the surface of colloidal CdSe quantum dots (QDs) for quantum dot-sensitized solar cells (QDSCs), by using mercaptopropionic acid (MPA) and iodide anions through a ligand exchange reaction in solution. This is found to be an effective way to improve the performance of QDSCs based on colloidal QDs. The results show that MPA can increase the coverage of the QDs on TiO2 electrodes and facilitate the hole extraction from the photoxidized QDs, and simultaneously, that the iodide anions can remedy the surface defects of the CdSe QDs and thus reduce the recombination loss in the device. This hybrid passivation treatment leads to a significant enhancement of the power conversion efficiency of the QDSCs by 41%. Furthermore, an optimal ratio of iodide ions to MPA was determined for favorable hybrid passivation; results show that excessive iodine anions are detrimental to the loading of the QDs. This study demonstrates that the improvement in QDSC performance can be realized by using a combination of different functional ligands to passivate the QDs, and that ligand exchange in solution can be an effective approach to introduce different ligands.

  16. Tribological performance of Graphene/Carbon nanotube hybrid reinforced Al2O3 composites

    Science.gov (United States)

    Yazdani, Bahareh; Xu, Fang; Ahmad, Iftikhar; Hou, Xianghui; Xia, Yongde; Zhu, Yanqiu

    2015-06-01

    Tribological performance of the hot-pressed pure Al2O3 and its composites containing various hybrid contents of graphene nanoplatelets (GNPs) and carbon nanotubes (CNTs) were investigated under different loading conditions using the ball-on-disc method. Benchmarked against the pure Al2O3, the composite reinforced with a 0.5 wt% GNP exhibited a 23% reduction in the friction coefficient along with a promising 70% wear rate reduction, and a hybrid reinforcement consisting of 0.3 wt.% GNPs + 1 wt.% CNTs resulted in even better performance, with a 86% reduction in the wear rate. The extent of damage to the reinforcement phases caused during wear was studied using Raman spectroscopy. The wear mechanisms for the composites were analysed based on the mechanical properties, brittleness index and microstructural characterizations. The excellent coordination between GNPs and CNTs contributed to the excellent wear resistance property in the hybrid GNT-reinforced composites. GNPs played the important role in the formation of a tribofilm on the worn surface by exfoliation; whereas CNTs contributed to the improvement in fracture toughness and prevented the grains from being pulled out during the tribological test.

  17. Optimizing performance of hybrid FSO/RF networks in realistic dynamic scenarios

    Science.gov (United States)

    Llorca, Jaime; Desai, Aniket; Baskaran, Eswaran; Milner, Stuart; Davis, Christopher

    2005-08-01

    Hybrid Free Space Optical (FSO) and Radio Frequency (RF) networks promise highly available wireless broadband connectivity and quality of service (QoS), particularly suitable for emerging network applications involving extremely high data rate transmissions such as high quality video-on-demand and real-time surveillance. FSO links are prone to atmospheric obscuration (fog, clouds, snow, etc) and are difficult to align over long distances due the use of narrow laser beams and the effect of atmospheric turbulence. These problems can be mitigated by using adjunct directional RF links, which provide backup connectivity. In this paper, methodologies for modeling and simulation of hybrid FSO/RF networks are described. Individual link propagation models are derived using scattering theory, as well as experimental measurements. MATLAB is used to generate realistic atmospheric obscuration scenarios, including moving cloud layers at different altitudes. These scenarios are then imported into a network simulator (OPNET) to emulate mobile hybrid FSO/RF networks. This framework allows accurate analysis of the effects of node mobility, atmospheric obscuration and traffic demands on network performance, and precise evaluation of topology reconfiguration algorithms as they react to dynamic changes in the network. Results show how topology reconfiguration algorithms, together with enhancements to TCP/IP protocols which reduce the network response time, enable the network to rapidly detect and act upon link state changes in highly dynamic environments, ensuring optimized network performance and availability.

  18. Larval and juvenile growth performance of Manila clam hybrids of two full-sib families

    Science.gov (United States)

    Huo, Zhongming; Yan, Xiwu; Zhao, Liqiang; Liang, Jian; Yang, Feng; Zhang, Guofan

    2015-06-01

    In order to determine whether growth performance could be improved by hybridizing full-sib families of Manila clam ( Ruditapes philippinarum), crosses between two full-sib families including self and reciprocal crosses were carried out. The effects of heterosis, combining ability and interaction on the growth of shell length were estimated. The results showed that the growth of hybrid larvae was intermediate between parents on days 6 and 9. Heterosis on shell length was observed, which varied at juvenile stage. The cross of ♂A × ♀B ( Hp varied between 10.41% and 68.27%) displayed larger heterosis than ♂B × ♀A ( Hp varied between 1.89% and 32.33%) did, suggesting that ♂A × ♀B was an ideal hatchery method of improving the growth performance of Manila clam. The variances of general combining ability (GCA), special combining ability (SCA) and interaction (I) were significant in shell length (P larvae and juveniles. The GCA for shell length of ♂A × ♀B was higher than that of ♂B × ♀A at both larval and juvenile stages. This confirmed that the cross between ♂A and ♀B showed great growth in shell length. In summary, the growth of Manila clam seeds could be improved by hybridizing selected parents from large numbers of full-sib families.

  19. Performance Characteristics of Hybrid Cycle Combined Absorption Heat Transformer and Absorption Refrigerating Machine

    Science.gov (United States)

    Iyoki, Shigeki; Otsuka, Shin-Ichi; Uemura, Tadashi

    In this paper, four kinds of hybrid cycles which combined the single-stage absorption refrigerating machine and four kinds of absorption heat transformers were proposed. It is possible that each of these hybrid cycles gets high temperature and low temperature from one cycle, simultaneously. As basic cycle of absorption heat transformer, the following were chosen: two kinds of single-stage absorption heat transformer and two kinds of two-stage absorption heat transformer. As a working medium-absorbent system, H2O-LiBr system, H2O-LiBr-LiNO3 system, H2O-LiBr-LiNO3-LiCl system, H2O-LiBr-C2H6O2 system and H2O-LiNO3-LiCl system were adopted. Using these five kinds of working medium-absorbent system, the performance characteristics of four kinds of hybrid cycle were simulated. And the performance characteristics of these cycles were compared.

  20. Nanocellulose Derivative/Silica Hybrid Core-Shell Chiral Stationary Phase: Preparation and Enantioseparation Performance

    Directory of Open Access Journals (Sweden)

    Xiaoli Zhang

    2016-05-01

    Full Text Available Core-shell silica microspheres with a nanocellulose derivative in the hybrid shell were successfully prepared as a chiral stationary phase by a layer-by-layer self-assembly method. The hybrid shell assembled on the silica core was formed using a surfactant as template by the copolymerization reaction of tetraethyl orthosilicate and the nanocellulose derivative bearing triethoxysilyl and 3,5-dimethylphenyl groups. The resulting nanocellulose hybrid core-shell chiral packing materials (CPMs were characterized and packed into columns, and their enantioseparation performance was evaluated by high performance liquid chromatography. The results showed that CPMs exhibited uniform surface morphology and core-shell structures. Various types of chiral compounds were efficiently separated under normal and reversed phase mode. Moreover, chloroform and tetrahydrofuran as mobile phase additives could obviously improve the resolution during the chiral separation processes. CPMs still have good chiral separation property when eluted with solvent systems with a high content of tetrahydrofuran and chloroform, which proved the high solvent resistance of this new material.

  1. Fabrication and Characterization of Polyimide-CNTs hybrid membrane to enhance high performance CO2 separation

    Directory of Open Access Journals (Sweden)

    Tutuk Djoko Kusworo

    2015-03-01

    Full Text Available This study investigates the CO2 separation performance of a hybrid membranes flat sheet based on polyimide incorporated with carbon nanotubes (CNTs particles. CNTs was selected and its loading were a 1 wt% in total solid. The hybrid composite membranes were fabricated in order to increase their separation performance for the gaseous mixture of CO2 and CH4. Hybrid Composite  membrane incorporated carbon nanotubes were mannufactured  by the dry-wet phase inversion technique using flat sheet membrane casting machine system,  in which the CNTs were embedded into the polyimide membrane and the resulting membranes were characterized. The results from the FESEM, DSC and FTIR analysis confirmed that chemical modification on carbon nanotubes surface had taken place. Sieve-in-a-cage’ morphology observed shows the poor adhesion between polymer and unmodified CNT. The results revealed that the good multi-wall carbon nanotubes dispersion leads to enhanced gas permeation properties. It is also concluded that addition of carbon nanotubes particles into the matrix of Polyimide polymer has significant effect on the membrane structure and properties.

  2. An Ultrahigh-Performance Photodetector based on a Perovskite-Transition-Metal-Dichalcogenide Hybrid Structure.

    Science.gov (United States)

    Kang, Dong-Ho; Pae, Seong Ryul; Shim, Jaewoo; Yoo, Gwangwe; Jeon, Jaeho; Leem, Jung Woo; Yu, Jae Su; Lee, Sungjoo; Shin, Byungha; Park, Jin-Hong

    2016-09-01

    An ultrahigh performance MoS2 photodetector with high photoresponsivity (1.94 × 10(6) A W(-1) ) and detectivity (1.29 × 10(12) Jones) under 520 nm and 4.63 pW laser exposure is demonstrated. This photodetector is based on a methyl-ammonium lead halide perovskite/MoS2 hybrid structure with (3-aminopropyl)triethoxysilane doping. The performance degradation caused by moisture is also minimized down to 20% by adopting a new encapsulation bilayer of octadecyltrichlorosilane/polymethyl methacrylate.

  3. Performance Analysis for Regional Satellite Positioning System Based upon GEO/HEO Hybrid Constellation

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Scheme of positioning constellation would greatly influence the positioning performance. In this paper, a GEO/HEO hybrid constellation with 3 HEO satellites deployed in 3 orbits and 3 GEO satellites for regional positioning is presented. Firstly, elements for 3 GEO and 3 HEO are optimized from regional visibility for the selected region of interest. Secondly, positioning performance is provided through GDOP(geometric dilution of precision) and PDOP(positional dilution of precision). Simulation results show that similar accuracy with GPS can be gained by this constellation.

  4. Enhanced photovoltaic performance of organic/silicon nanowire hybrid solar cells by solution-evacuated method.

    Science.gov (United States)

    Wang, Wei-Li; Zou, Xian-Shao; Zhang, Bin; Dong, Jun; Niu, Qiao-Li; Yin, Yi-An; Zhang, Yong

    2014-06-01

    A method has been developed to fabricate organic-inorganic hybrid heterojunction solar cells based on n-type silicon nanowire (SiNW) and poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) hybrid structures by evacuating the PEDOT:PSS solution with dip-dropping on the top of SiNWs before spin-coating (solution-evacuating). The coverage and contact interface between PEDOT:PSS and SiNW arrays can be dramatically enhanced by optimizing the solution-evacuated time. The maximum power conversion efficiency (PCE) reaches 9.22% for a solution-evacuated time of 2 min compared with 5.17% for the untreated pristine device. The improvement photovoltaic performance is mainly attributed to better organic coverage and contact with an n-type SiNW surface.

  5. CRES` wind-diesel hybrid system: system identification and performance testing

    Energy Technology Data Exchange (ETDEWEB)

    Vionis, P.S.; Fragoulis, A.N.; Ladakakos, P.D. [Center for Renewable Energy Sources (C.R.E.S.), Pikermi (Greece)

    1996-12-31

    A Wind-Diesel hybrid system has been developed at CRES for investigating the parallel operation of Wind Turbines and Diesel Generators into Autonomous Weak Grids. The system`s architecture is flexible enough so that it can be effectively used for optimising the integration of renewable energy sources in such autonomous power systems, while ensuring the successful implementation of innovative control strategies and testing of new design concepts. In this paper, the design of the wind-diesel simulator and its basic operation modes are described. Results of the components identification procedure are presented. The relevant analysis reveals the components` characteristics under various modes of operation along with the subsystem`s operation limits. The methodology set up for system testing and evaluation has been verified. Results of the first performance tests of the Wind-Diesel hybrid system showing its capabilities are presented and discussed. (Author)

  6. Performance simulation and analysis of a fuel cell/battery hybrid forklift truck

    DEFF Research Database (Denmark)

    Hosseinzadeh, Elham; Rokni, Masoud; Advani, Suresh G.

    2013-01-01

    The performance of a forklift truck powered by a hybrid system consisting of a PEM fuel cell and a lead acid battery is modeled and investigated by conducting a parametric study. Various combinations of fuel cell size and battery capacity are employed in conjunction with two distinct control...... strategies to study their effect on hydrogen consumption and battery state-of-charge for two drive cycles characterized by different operating speeds and forklift loads. The results show that for all case studies, the combination of a 110 cell stack with two strings of 55 Ah batteries is the most economical...... choice for the hybrid system based on system size and hydrogen consumption. In addition, it is observed that hydrogen consumption decreases by about 24% when the maximum speed of the drive cycle is decreased from 4.5 to 3 m/s. Similarly, by decreasing the forklift load from 2.5 to 1.5 ton, the hydrogen...

  7. Performance studies on mechanical + adsorption hybrid compression refrigeration cycles with HFC 134a

    Energy Technology Data Exchange (ETDEWEB)

    Banker, N.D.; Dutta, P.; Srinivasan, K. [Department of Mechanical Engineering, Indian Institute of Science, Bangalore 560 012 (India); Prasad, M. [Thermal Systems Division, ISRO Satellite Centre, Bangalore 560 017 (India)

    2008-12-15

    This paper presents the results of an investigation on the efficacy of hybrid compression process for refrigerant HFC 134a in cooling applications. The conventional mechanical compression is supplemented by thermal compression using a string of adsorption compressors. Activated carbon is the adsorbent for the thermal compression segment. The alternatives of bottoming either mechanical or thermal compression stages are investigated. It is shown that almost 40% energy saving is realizable by carrying out a part of the compression in a thermal compressor compared to the case when the entire compression is carried out in a single-stage mechanical compressor. The hybrid compression is feasible even when low grade heat is available. Some performance indictors are defined and evaluated for various configurations. (author)

  8. Improved performance of cylindrical hybrid supercapacitor using activated carbon/ niobium doped hydrogen titanate

    Science.gov (United States)

    Lee, Jeong Hyun; Kim, Hong-Ki; Baek, Esther; Pecht, Michael; Lee, Seung-Hwan; Lee, Young-Hie

    2016-01-01

    A cylindrical hybrid supercapacitor is fabricated using activated carbon positive electrode and H2Ti12-xNbxO25 (0 ≤ x ≤ 0.6) negative electrode materials. The hybrid supercapacitor using H2Ti11.85Nb0.15O25 exhibits the best electrochemical performance. It has a capacitance of 78.4 F g-1, charge transfer resistance (Rct) of 0.03 Ω, capacitance retention of 91.4% after 1000 cycles at 3.0 A g-1 and energy density of 24.3 W h kg-1 at a power density of 1794.6 W kg-1. Therefore, the Nb doped HTO negative electrode material is a promising candidate as an energy storage system for electric vehicles (EVs).

  9. In-service performance and behavior characterization of the hybrid composite bridge system - a case study

    CERN Document Server

    Civitillo, John M; Gheitasi, Amir; Saliba, Mark; Kassner, Bernard L

    2014-01-01

    The Hybrid Composite Beam (HCB) system is an innovative structural technology that has been recently used in bridge construction within the U.S. transportation network. In this system, the superstructure consists of a conventional reinforced concrete deck supported by Hybrid Composite Beams. Each beam is comprised of a glassfiber reinforced polymer (FRP) box shell containing a tied parabolic concrete arch. Inclined stirrups provide shear integrity and enforce composite action between the HCBs and the concrete deck. This paper focuses on evaluating the in-service performance of a newly constructed HCB bridge superstructure located on Route 205 in Colonial Beach, Virginia. A live load test was conducted using tandem axle dump trucks under both quasi-static and dynamic conditions. Results obtained from the experimental investigation were used to determine three key behavior characteristics. Dynamic amplification and lateral load distribution were found to be reasonable in comparison to the assumed design values....

  10. High Performance Ultraviolet Photodetector Fabricated with ZnO Nanoparticles-graphene Hybrid Structures

    Institute of Scientific and Technical Information of China (English)

    Jin-yang Liu; Xin-xin Yu; Guang-hui Zhang; Yu-kun Wu; Kun Zhang; Nan Pan; Xiao-ping Wang

    2013-01-01

    Ultraviolet (UV) photodetector constructed by ZnO material has attracted intense research and commercial interest.However,its photoresistivity and photoresonse are still unsatisfied.Herein,we report a novel method to assemble ZnO nanoparticles (NPs) onto the reduced graphite oxide (RGO) sheet by simple hydrothermal process without any surfactant.It is found that the high-quality crystallized ZnO NPs with the average diameter of 5 nm are well dispersed on the RGO surface,and the density of ZnO NPs can be readily controlled by the concentration of the precursor.The photodetector fabricated with this ZnO NPs-RGO hybrid structure demonstrates an excellent photoresponse for the UV irradiation.The results make this hybrid especially suitable as a novel material for the design and fabrication of high performance UV photodector.

  11. Performance of astronomical beam combiner prototypes fabricated by hybrid sol-gel technology.

    Science.gov (United States)

    Ghasempour, Askari; Leite, A M P; Alexandre, D; Reynaud, F; Marques, P V S; Garcia, P J V; Moreira, P J

    2010-04-26

    Integrated optics coaxial two, three and four telescope beam combiners have been fabricated by hybrid sol-gel technology for astronomical applications. Temporal and spectral analyses of the output interferometric signal have been performed, and their results are in mutual good agreement. The results of the characterization method employed are cross-checked using contrast measurements obtained independently, demonstrating that the chromatic differential dispersion is the main contributer to contrast reduction. The mean visibility of the fabricated devices is always higher than 95 %, obtained using a source with spectral bandwidth of 50 nm. These results show the capability of hybrid sol-gel technology for fast prototyping of complex chip designs used in astronomical applications.

  12. High performance protection circuit for power electronics applications

    Science.gov (United States)

    Tudoran, Cristian D.; Dǎdârlat, Dorin N.; Toşa, Nicoleta; Mişan, Ioan

    2015-12-01

    In this paper we present a high performance protection circuit designed for the power electronics applications where the load currents can increase rapidly and exceed the maximum allowed values, like in the case of high frequency induction heating inverters or high frequency plasma generators. The protection circuit is based on a microcontroller and can be adapted for use on single-phase or three-phase power systems. Its versatility comes from the fact that the circuit can communicate with the protected system, having the role of a "sensor" or it can interrupt the power supply for protection, in this case functioning as an external, independent protection circuit.

  13. High performance protection circuit for power electronics applications

    Energy Technology Data Exchange (ETDEWEB)

    Tudoran, Cristian D., E-mail: cristian.tudoran@itim-cj.ro; Dădârlat, Dorin N.; Toşa, Nicoleta; Mişan, Ioan [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, PO 5 Box 700, 400293 Cluj-Napoca (Romania)

    2015-12-23

    In this paper we present a high performance protection circuit designed for the power electronics applications where the load currents can increase rapidly and exceed the maximum allowed values, like in the case of high frequency induction heating inverters or high frequency plasma generators. The protection circuit is based on a microcontroller and can be adapted for use on single-phase or three-phase power systems. Its versatility comes from the fact that the circuit can communicate with the protected system, having the role of a “sensor” or it can interrupt the power supply for protection, in this case functioning as an external, independent protection circuit.

  14. Long-Range Interfacial Electrochemical Electron Transfer of Pseudomonas aeruginosa Azurin-Gold Nanoparticle Hybrid Systems

    DEFF Research Database (Denmark)

    Jensen, Palle Skovhus; Chi, Qijin; Zhang, Jingdong

    2009-01-01

    We have prepared a "hybrid" of the blue copper protein azurin (Pseudomonas aeruginosa) and a 3 nm gold nanoparticle (AuNP). The AuNP/azurin hybrid was assembled on a Au(111)-electrode surface in a two-step process. The AuNP was first attached to the Au(111) electrode via Au-S chemisorption of a 4...

  15. Role of microstructure in the electron-hole interaction of hybrid lead halide perovskites

    Science.gov (United States)

    Grancini, Giulia; Srimath Kandada, Ajay Ram; Frost, Jarvist M.; Barker, Alex J.; de Bastiani, Michele; Gandini, Marina; Marras, Sergio; Lanzani, Guglielmo; Walsh, Aron; Petrozza, Annamaria

    2015-10-01

    Organic-inorganic metal halide perovskites have demonstrated high power conversion efficiencies in solar cells and promising performance in a wide range of optoelectronic devices. The existence and stability of bound electron-hole pairs in these materials and their role in the operation of devices with different architectures remains a controversial issue. Here we demonstrate, through a combination of optical spectroscopy and multiscale modelling as a function of the degree of polycrystallinity and temperature, that the electron-hole interaction is sensitive to the microstructure of the material. The long-range order is disrupted by polycrystalline disorder and the variations in electrostatic potential found for smaller crystals suppress exciton formation, while larger crystals of the same composition demonstrate an unambiguous excitonic state. We conclude that fabrication procedures and morphology strongly influence perovskite behaviour, with both free carrier and excitonic regimes possible, with strong implications for optoelectronic devices.

  16. Hybrid (particle in cell-fluid) simulation of ion-acoustic soliton generation including super-thermal and trapped electrons

    Energy Technology Data Exchange (ETDEWEB)

    Nopoush, M.; Abbasi, H. [Faculty of Physics, Amirkabir University of Technology, P. O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

    2011-08-15

    The present paper is devoted to the simulation of the nonlinear disintegration of a localized perturbation into an ion-acoustic soliton in a plasma. Recently, this problem was studied by a simple model [H. Abbasi et al., Plasma Phys. Controlled Fusion 50, 095007 (2008)]. The main assumptions were (i) in the electron velocity distribution function (DF), the ion-acoustic soliton velocity was neglected in comparison to the electron thermal velocity, (ii) on the ion-acoustic evolution time-scale, the electron velocity DF was assumed to be stationary, and (iii) the calculation was restricted to the small amplitude case. In order to generalize the model, one has to consider the evolution of the electron velocity DF for finite amplitudes. For this purpose, a one dimensional electrostatic hybrid code, particle in cell (PIC)-fluid, was designed. It simulates the electrons dynamics by the PIC method and the cold ions dynamics by the fluid equations. The plasma contains a population of super-thermal electrons and, therefore, a Lorentzian (kappa) velocity DF is used to model the high energy tail in the electron velocity DF. Electron trapping is included in the simulation in view of their nonlinear resonant interaction with the localized perturbation. A Gaussian initial perturbation is used to model the localized perturbation. The influence of both the trapped and the super-thermal electrons on this process is studied and compared with the previous model.

  17. PERFORMANCE EVALUATION OF HYBRID FUZZY LOGIC CONTROLLER FOR BRUSHLESS DC MOTOR DRIVE

    Directory of Open Access Journals (Sweden)

    C. SUBBA RAMI REDDY

    2011-06-01

    Full Text Available This paper presents Hybrid fuzzy logic controller (HFLC for the well developed and sophisticated simulation model of Brush less DC (BLDC motor drive using MATLAB. The developed simulation model has been examined by the PID controller and HFLC. The performance of the controllers is evaluated more precisely from various simulation studies for variations in the load torque and speed of BLDC motor drive. A performance comparison of two controllers is also carried out by taking various performance measures such as settling time, steady state error, peak overshoot, the integral of the absolute value of the error (IAE and the integral of the time-weighted squared error (ITSE. The results confirm that the developed simulation model is very convenient for the precise evaluation of performance and the HFLC shows improved performance over the PID controller in terms of disturbance rejection or parameter variation.

  18. PEMFC performance of MEAS based on Nafion{sup R} and sPSEBS hybrid membranes

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Carretero, F.J.; Compan, V. [Univ, Politecnica de Valencia, Valencia (Spain). Dept. Termodinamica Aplicada; Suarez, K.; Solorza, O. [Inst. Politecnico Nacional, Centro de Investigacion y de Estudios Avanzados, Mexico City (Mexico). Dept. de Quimica; Riande, E. [Inst. de Ciencia y Tecnologia de Polimeros, Madrid (Spain)

    2010-07-15

    Important scientific, technical and economic problems must be solved before widespread commercialization of polymer electrolyte membrane fuel cells (PEMFC). The main issues facing the development of commercial low temperature fuel cells are the synthesis of efficient solid electrolytes separating the anode from the cathode as well as the development of cheaper catalysts for fuel oxidation. This study involved the preparation of hybrid membranes based on Nafion 117 and sulfonated Calprene H6120 containing partially sulfonated inorganic fillers such as silica, SBA-15 and sepiolite. The feasibility of using the membranes as polyelectrolytes for low temperature fuel cells was then evaluated. The water uptake of Nafion hybrid membranes is 1/3 to 1/4 of that in composite membranes based on sulfonated Calprene H6120. The proton conductivity of Nafion 117 hybrid membranes-electrode assemblies is nearly 1/5 of the pristine Nafion membrane assembly. Sulfonated Calprene H6120 hybrid membranes typically have better proton conductivity than the Nafion 117 composites. The performance of fuel cells containing different MEAs was examined by measuring their polarization curves in different operating conditions. The kinetic parameters governing the voltage dependence on current density were also estimated. It was concluded that the superior performance of the fuel cells with MEAs of NAF-SEP, sPSEBS-SIL and sPSEBS-SBA is not due to the membranes themselves, but to the kinetic processes that occur at the electrodes, which in this study were less efficient for fuel cells with the Nafion MEA. 34 refs., 3 tabs., 9 figs.

  19. Preparation of hybrid monolithic columns via "one-pot" photoinitiated thiol-acrylate polymerization for retention-independent performance in capillary liquid chromatography.

    Science.gov (United States)

    Zhang, Haiyang; Ou, Junjie; Liu, Zhongshan; Wang, Hongwei; Wei, Yinmao; Zou, Hanfa

    2015-09-01

    A novel "one-pot" approach was developed for ultrarapid preparation of various hybrid monolithic columns in UV-transparent fused-silica capillaries via photoinitiated thiol-acrylate polymerization of an acrylopropyl polyhedral oligomertic silsesquioxane (acryl-POSS) and a monothiol monomer (1-octadecanethiol or sodium 3-mercapto-1-propanesulfonate) within 5 min, in which the acrylate not only homopolymerizes, but also couples with the thiol. This unique combination of two types of free-radical reaction mechanisms offers a simple way to fabricate various acrylate-based hybrid monoliths. The physical characterization, including scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, and thermal gravimetric analysis was performed. The results indicated that the monothiol monomers were successfully incorporated into acryl-POSS-based hybrid monoliths. The column efficiencies for alkylbenzenes on the C18-functionalized hybrid monolithic column reached to 60 000-73 500 plates/m at the velocity of 0.33 mm/s in capillary liquid chromatography, which was far higher than that of previously reported POSS-based columns prepared via thermal-initiated free-radical polymerization without adding any thiol monomers. By plotting the plate height (H) of the alkylbenzenes versus the linear velocity (u) of the mobile phase, the results revealed a retention-independent efficient performance of small molecules in the isocratic elution. These results indicated that more homogeneous hybrid monoliths formed via photoinitiated thiol-acrylate polymerization; particularly, the use of the multifunctional cross-linker possibly prevented the generation of gel-like micropores, reducing mass transfer resistance (C-term). Another sulfonate-containing hybrid monolithic column also exhibited hydrophobicity and ion-exchange mechanism, and the dynamic binding capacity was calculated as 71.1 ng/cm (75 μm i.d.).

  20. Electron energy distribution functions and negative ion concentrations in tandem and hybrid multicusp negative hydrogen ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, M.B. (Dublin City Univ. (Ireland). Dept. of Physics); Bacal, M. (Ecole Polytechnique, 91 - Palaiseau (France). Lab. de Physique des Milieux Ionises); Graham, W.G. (Queen' s Univ., Belfast, Northern Ireland (UK). School of Mathematics and Physics)

    1991-03-14

    The second derivative of a Langmuir probe characteristic is used to establish the electron energy distribution function (EEDF) in both a tandem and hybrid multicusp H{sup -} ion source. Moveable probes are used to establish the spatial variation of the EEDF. The negative ion density is measured by laser induced photo-detachment. In the case of the hybrid source the EEDF consists of a cold Maxwellian in the central region of the source; the electron temperature increases with increasing discharge current (rising from 0.3 eV at 1 A to 1.2 eV at 50 A when the pressure is 0.4 Pa). A hot electron tail exists in the EEDF of the driver region adjacent to each filament which is shown to consist of a distinct group of primary electrons at low pressure (0.08 Pa) but becomes degraded mainly through inelastic collisions at higher pressures (0.27 Pa). The tandem source, on the other hand, has a single driver region which extends throughout the central region. The primary electron confinement times are much longer so that even at the lowest pressure considered (0.07 Pa) the primaries are degraded. In both cases the measured EEDF at specific locations and values of discharge operating parameters are used to establish the rate coefficients for the processes of importance in H{sup -} production and destruction. (author).

  1. Performance-Driven Hybrid Full-Body Character Control for Navigation and Interaction in Virtual Environments

    Science.gov (United States)

    Mousas, Christos; Anagnostopoulos, Christos-Nikolaos

    2017-06-01

    This paper presents a hybrid character control interface that provides the ability to synthesize in real-time a variety of actions based on the user's performance capture. The proposed methodology enables three different performance interaction modules: the performance animation control that enables the direct mapping of the user's pose to the character, the motion controller that synthesizes the desired motion of the character based on an activity recognition methodology, and the hybrid control that lies within the performance animation and the motion controller. With the methodology presented, the user will have the freedom to interact within the virtual environment, as well as the ability to manipulate the character and to synthesize a variety of actions that cannot be performed directly by him/her, but which the system synthesizes. Therefore, the user is able to interact with the virtual environment in a more sophisticated fashion. This paper presents examples of different scenarios based on the three different full-body character control methodologies.

  2. Simulating Study on Drive System Performance for Hybrid Electric Bus Based on ADVISOR

    Directory of Open Access Journals (Sweden)

    Wang Xingxing

    2017-01-01

    Full Text Available Hybrid electric bus has a number of advantages when compared with ordinary passenger cars, but in the dynamic matching and the vehicle performance are difficult to detect, thus limits its development process. In this paper, combined with the actual models, the hybrid electric bus module parameters were modified in the software of ADVISOR (Advanced Vehicle Simulator, main including: module of the vehicle, the wheel module, motor module, a battery module and engine module, three kinds of bus models for A, B and C were established, and the related performance that need to be analyzed was set up, such as acceleration, gradability, emissions and energy utilization and so on, in order to ensure the vehicle running in the same environment and convenient for comparison, a fixed vehicle driving cycles was chose, then the simulation results was analyzed, and the various performance was compared with the dynamic indicators and economic indicators which determined by referencing of traditional city bus standard and each other, and finally, the performance optimal model of B was chose out which can meet the demand, its related performance parameters of the simulation results are as follows: the best gradability is 26%, maximum speed is 72.7km/h, maximum acceleration is 1.7m/s2, 0~50km/h acceleration time is 9.5s and fuel consumption is 25L/km.

  3. Scalable-Production, Self-Powered TiO2 Nanowell-Organic Hybrid UV Photodetectors with Tunable Performances.

    Science.gov (United States)

    Zheng, Lingxia; Yu, Pingping; Hu, Kai; Teng, Feng; Chen, Hongyu; Fang, Xiaosheng

    2016-12-14

    Hybrid inorganic-organic photoelectric devices draw considerable attention because of their unique features by combining the tunable functionality of organic molecules and the superior intrinsic carrier mobilities of inorganic semiconductors. An ordered thin layer of TiO2 nanowells is formed in situ with shallow nanoconcave patterns without cracking with scalable production by a facile and economic strategy, and these layers are used as building blocks to construct hybrid UV photodetectors (PDs). Organic conducting polymers (polyaniline (PANI) with various morphologies) have been exploited as p-type materials, enabling tunable photodetection performances at zero bias. The thin layer of n-type TiO2 nanowells is favorable for electron transport and light absorption with respect to their conventional nanotubular counterparts, while PANI acts as a hopping state or bridge to largely enhance the transition probability of the valence electrons in TiO2 to its conduction band, resulting in an increase in photocurrent in a self-powered mode. In particular, the lowest polyaniline loading sample (TP1) exhibits the highest responsivity (3.6 mA·W(-1)), largest on-off switching ratio (∼10(3)), excellent wavelength selectivity, fast response speed (3.8/30.7 ms), and good stability under 320 nm light illumination (0.56 mW·cm(-2)) without an external energy supply. This work might be of great value in developing tunable UV photoresponse materials with respect to low cost and a large area for future energy-efficient optoelectronic devices.

  4. Nature of electron correlation and hybridization in NixCu1−xMnSb Heusler alloys

    Directory of Open Access Journals (Sweden)

    I. Sarkar

    2016-08-01

    Full Text Available The electronic structure of Heusler alloys having mixed magnetic phases, comprising of vicinal anti-ferromagnetic and ferromagnetic orders, is of great significance. We present the results of an electronic structure study on NixCu1−xMnSb Heusler alloys, using Mn-2p core-level photoemission spectroscopy. Room temperature data in the paramagnetic phase reveal a non-monotonic variation of both electron correlation strength and conduction-band hybridization such that the former enhances while the latter weakens for compositions showing a mixed phase relative to compositions at the phase boundaries to the ordered phases. The results suggest a possible electronic driving force for settling mixed-magnetic phases.

  5. Dynamics of the electron thermal diffusivity at improved energy confinement during lower hybrid plasma heating in the FT-2 tokamak

    Science.gov (United States)

    Kouprienko, D. V.; Altukhov, A. B.; Gurchenko, A. D.; Gusakov, E. Z.; Kantor, M. Yu.; Lashkul, S. I.; Esipov, L. A.

    2010-05-01

    The dynamics of electron heat transport at improved energy confinement during lower hybrid plasma heating in the FT-2 tokamak was studied experimentally. Evolution of the profiles of the electron temperature and density was thoroughly investigated under conditions of fast variation in the plasma parameters. The energy balance in the electron channel is calculated with the help of the ASTRA code by using the measured plasma parameters. Correlation is revealed between the dynamics of electron heat transport and the behavior of small-scale drift turbulence measured using the enhanced scattering correlation diagnostics. The suppression of heat transfer and turbulence agrees well with the increase in the shear of poloidal plasma rotation calculated from experimental data in the neoclassical approximation.

  6. Photovoltaics: Highly Efficient Hybrid Photovoltaics Based on Hyperbranched Three-Dimensional TiO 2 Electron Transporting Materials (Adv. Mater. 18/2015)

    KAUST Repository

    Mahmood, Khalid

    2015-05-01

    Solution-processed hybrid photovoltaics are a potentially disruptive third-generation solar cell technology. On page 2859, A. Amassian and co-workers demonstrate that an electrospun hyperbranched electron-transporting material is capable of achieving highly efficient hybrid solar cells across different platforms, including lead-halide perovskites (15.5%) and dye-sensitized solar cells (11.2%).

  7. Redox-active organometallics: magnetic and electronic couplings through carbon-silicon hybrid molecular connectors.

    Science.gov (United States)

    Hamon, Paul; Justaud, Frederic; Cador, Olivier; Hapiot, Philippe; Rigaut, Stéphane; Toupet, Loïc; Ouahab, Lahcène; Stueger, Harald; Hamon, Jean-René; Lapinte, Claude

    2008-12-24

    Treatment of the triflate complex Cp*(dppe)FeOTf [12; Cp* = eta(5)-C(5)(CH(3))(5), dppe = 1,2-bis(diphenylphosphino)ethane, OTf = CF(3)SO(3)] with an excess of HC[triple bond]C-(Si(CH(3))(2))(x)-C[triple bond]CH (x = 2-4) in diethyl ether provides the binuclear bis(vinylidene) derivatives [Cp*(dppe)Fe=C=CH(Si(CH(3))(2))(x)CH=C=Fe(dppe)Cp*][OTf](2) (x = 2, 13; x = 3, 14; x = 4, 15), which were isolated as ochre solids and rapidly characterized by FT-IR, (1)H, (31)P, and (13)C NMR spectroscopies. The complexes 13-15 were reacted with potassium tert-butoxide to afford the bis(alkynediyl) complexes [Cp*(dppe)Fe-C[triple bond]C(Si(CH(3))(2))(x)C[triple bond]C-Fe(dppe)Cp*] (x = 2, 1; x = 3, 2; x = 4, 3), which were isolated as orange powders in yields ranging from 76 to 91%. The IR, cyclic voltammetry, and UV-vis data obtained for 1-3 and the X-ray crystal structures determined for 1 and 3 reveal the importance of the sigma-pi conjugation (hyperconjugation) between the Si-Si sigma bond and the adjacent C[triple bond]C pi-symmetric orbitals in the description of the electronic structure of the ground state of these complexes. When reacted at low temperature with 2 equiv of [(C(5)H(5))(2)Fe]X or AgX [X = BPh(4), B(3,5-(CF(3))(2)C(6)H(3))(4))], compounds 1-3 provide 1[X](2), 2[X](2), and 3[X](2), which can be isolated and stored below -20 degrees C. EPR spectroscopy and magnetization measurements established that the superexchange interaction propagates through the Si-Si bonds (J = -0.97(2) cm(-1) for 3[X](2)). UV-vis-near-IR spectra were obtained with an optically transparent thin-layer electrosynthetic (OTTLE) cell for 1-3[OTf](n) (n = 0-2). A band with a maximum that increases from 6400 cm(-1) (1[OTf]) to 8500 cm(-1) (3[OTf]) observed for the mixed-valence species was ascribed to intervalence charge transfer evidencing photodriven electron transfer through the carbon-silicon hybrid connectors with H(ab) parameters ranging from 64 to 285 cm(-1).

  8. Hybrid utilization of solar energy. Part 2. Performance analyses of heating system with air hybrid collector; Taiyo energy no hybrid riyo ni kansuru kenkyu. 2. Kuki shunetsu hybrid collector wo mochiita danbo system no seino hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Yoshinaga, M.; Okumiya, M. [Nagoya University, Nagoya (Japan)

    1996-10-27

    For the effective utilization of solar energy at houses, a heating system using an air hybrid collector (capable of simultaneously performing heat collection and photovoltaic power generation). As the specimen house, a wooden house of a total floor area of 120m{sup 2} was simulated. Collected air is fanned into a crushed stone heat accumulator (capable of storing one day`s collection) or into a living room. The output of solar cell arrays is put into a heat pump (capable of handling a maximum hourly load of 36,327kJ/h) via an inverter so as to drive the fan (corresponding to average insolation on the heat collecting plate of 10.7MJ/hm{sup 2} and heat collecting efficiency of 40%), and shortage in power if any is supplied from the system interconnection. A hybrid collector, as compared with the conventional air collector, is lower in thermal efficiency but the merit that it exhibits with respect to power generation is far greater than what is needed to counterbalance the demerit. When the hybrid system is in heating operation, there is an ideal heat cycle of collection, accumulation, and radiation when the load is light, but the balance between accumulation and radiation is disturbed when the load is heavy. 4 refs., 8 figs., 3 tabs.

  9. Fabrication and interfacial electronic structure studies on polypyrrole/TiO2 nano hybrid systems for photovoltaic aspects.

    Science.gov (United States)

    Kumar, Ganesan Mohan; Kawakita, Jin; Jayavel, Ramasamy

    2011-05-01

    The progress in studying the interfacial electronic structures of the developing new class of hybrid organic/inorganic material systems have envisaged a new dimension into the field of photovoltaics, which could be of great help in understanding the nature of charge transfer in them. In this regard, electropolymerization of pyrrole monomers have been carried out at room temperature on the surface of TiO2 working electrodes (assisted by UV radiations) and their interfacial electronic structure has been studied as a function of the applied photo anodic potentials. The formation of polypyrrole deposits has been ensured using FT-IR and Raman spectroscopy. Surface analysis of the hybrid matrix revealed the tendency of polymer molecules to cover up the spherical surface of TiO2 nanoparticles that could help in improving the light absorption rate. Signals (bands) corresponding to pyrrole molecules observed in the ultraviolet photoelectron spectroscopy measurements have been correlated with the polaronic states formed and identified to shift as a function of the applied photo anodic potentials, revealing the decrease in work function of the hybrid system to take place (confirmed using cyclic voltammetry measurements). The decreasing trend in the work function elucidates the adjustment in electronic structure of the system (hybrid materials possessing smaller work functions are generally preferred for photovoltaic studies). The aforementioned behavioural aspects have been reasoned with the increase in overpotential values for polarization, from the decrease in up-take rate of the anionic dopant, which increases the current density values, thereby modifying the conductivity of the systems.

  10. Cooling Performance Characteristics on Mobile Air-Conditioning System for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Ho-Seong Lee

    2013-01-01

    Full Text Available This study investigates the cooling performance characteristics of the mobile air-conditioning system using R744 (CO2 for the hybrid electric vehicle as an alternative to both the R-134a and the conventional air-conditioning system. The developed air-conditioning system is operated with an electric driven compressor in the battery driving mode and a belt driven compressor in the engine driving mode. The cooling performance characteristics of the developed system have been analyzed by experiments under various operating conditions of inlet air temperature, air flow rates for the gas cooler side and evaporator side, and electric compressor revolution respectively. As a result, cooling performances of the tested air-conditioning system for the EDC driving mode (electricity driven compressor were better than those for the BDC driving mode (belt driven compressor. The cooling capacity and cooling COP of the tested air-conditioning system for both driving modes were over 5.0 kW and 2.0, respectively. The observed cooling performance of the tested air-conditioning system may be sufficient for the cabin cooling of hybrid electric vehicles.

  11. Hybrid Microscopy: Enabling Inexpensive High-Performance Imaging through Combined Physical and Optical Magnifications

    Science.gov (United States)

    Zhang, Yu Shrike; Chang, Jae-Byum; Alvarez, Mario Moisés; Trujillo-de Santiago, Grissel; Aleman, Julio; Batzaya, Byambaa; Krishnadoss, Vaishali; Ramanujam, Aishwarya Aravamudhan; Kazemzadeh-Narbat, Mehdi; Chen, Fei; Tillberg, Paul W.; Dokmeci, Mehmet Remzi; Boyden, Edward S.; Khademhosseini, Ali

    2016-03-01

    To date, much effort has been expended on making high-performance microscopes through better instrumentation. Recently, it was discovered that physical magnification of specimens was possible, through a technique called expansion microscopy (ExM), raising the question of whether physical magnification, coupled to inexpensive optics, could together match the performance of high-end optical equipment, at a tiny fraction of the price. Here we show that such “hybrid microscopy” methods—combining physical and optical magnifications—can indeed achieve high performance at low cost. By physically magnifying objects, then imaging them on cheap miniature fluorescence microscopes (“mini-microscopes”), it is possible to image at a resolution comparable to that previously attainable only with benchtop microscopes that present costs orders of magnitude higher. We believe that this unprecedented hybrid technology that combines expansion microscopy, based on physical magnification, and mini-microscopy, relying on conventional optics—a process we refer to as Expansion Mini-Microscopy (ExMM)—is a highly promising alternative method for performing cost-effective, high-resolution imaging of biological samples. With further advancement of the technology, we believe that ExMM will find widespread applications for high-resolution imaging particularly in research and healthcare scenarios in undeveloped countries or remote places.

  12. Design and verification of a hybrid nonlinear MRE vibration absorber for controllable broadband performance

    Science.gov (United States)

    Sun, S. S.; Yildirim, T.; Wu, Jichu; Yang, J.; Du, H.; Zhang, S. W.; Li, W. H.

    2017-09-01

    In this work, a hybrid nonlinear magnetorheological elastomer (MRE) vibration absorber has been designed, theoretically investigated and experimentally verified. The proposed nonlinear MRE absorber has the dual advantages of a nonlinear force-displacement relationship and variable stiffness technology; the purpose for coupling these two technologies is to achieve a large broadband vibration absorber with controllable capability. To achieve a nonlinear stiffness in the device, two pairs of magnets move at a rotary angle against each other, and the theoretical nonlinear force-displacement relationship has been theoretically calculated. For the experimental investigation, the effects of base excitation, variable currents applied to the device (i.e. variable stiffness of the MRE) and semi-active control have been conducted to determine the enhanced broadband performance of the designed device. It was observed the device was able to change resonance frequency with the applied current; moreover, the hybrid nonlinear MRE absorber displayed a softening-type nonlinear response with clear discontinuous bifurcations observed. Furthermore, the performance of the device under a semi-active control algorithm displayed the optimal performance in attenuating the vibration from a primary system to the absorber over a large frequency bandwidth from 4 to 12 Hz. By coupling nonlinear stiffness attributes with variable stiffness MRE technology, the performance of a vibration absorber is substantially improved.

  13. Hybrid Microscopy: Enabling Inexpensive High-Performance Imaging through Combined Physical and Optical Magnifications.

    Science.gov (United States)

    Zhang, Yu Shrike; Chang, Jae-Byum; Alvarez, Mario Moisés; Trujillo-de Santiago, Grissel; Aleman, Julio; Batzaya, Byambaa; Krishnadoss, Vaishali; Ramanujam, Aishwarya Aravamudhan; Kazemzadeh-Narbat, Mehdi; Chen, Fei; Tillberg, Paul W; Dokmeci, Mehmet Remzi; Boyden, Edward S; Khademhosseini, Ali

    2016-03-15

    To date, much effort has been expended on making high-performance microscopes through better instrumentation. Recently, it was discovered that physical magnification of specimens was possible, through a technique called expansion microscopy (ExM), raising the question of whether physical magnification, coupled to inexpensive optics, could together match the performance of high-end optical equipment, at a tiny fraction of the price. Here we show that such "hybrid microscopy" methods--combining physical and optical magnifications--can indeed achieve high performance at low cost. By physically magnifying objects, then imaging them on cheap miniature fluorescence microscopes ("mini-microscopes"), it is possible to image at a resolution comparable to that previously attainable only with benchtop microscopes that present costs orders of magnitude higher. We believe that this unprecedented hybrid technology that combines expansion microscopy, based on physical magnification, and mini-microscopy, relying on conventional optics--a process we refer to as Expansion Mini-Microscopy (ExMM)--is a highly promising alternative method for performing cost-effective, high-resolution imaging of biological samples. With further advancement of the technology, we believe that ExMM will find widespread applications for high-resolution imaging particularly in research and healthcare scenarios in undeveloped countries or remote places.

  14. High Performance Hybrid Two Layer Router Architecture for FPGAs Using Network On Chip

    CERN Document Server

    Ezhumalai, P; Arun, C; Sakthivel, P; Sridharan, D

    2010-01-01

    Networks on Chip is a recent solution paradigm adopted to increase the performance of Multicore designs. The key idea is to interconnect various computation modules (IP cores) in a network fashion and transport packets simultaneously across them, thereby gaining performance. In addition to improving performance by having multiple packets in flight, NoCs also present a host of other advantages including scalability, power efficiency, and component reuse through modular design. This work focuses on design and development of high performance communication architectures for FPGAs using NoCs Once completely developed, the above methodology could be used to augment the current FPGA design flow for implementing multicore SoC applications. We design and implement an NoC framework for FPGAs, MultiClock OnChip Network for Reconfigurable Systems (MoCReS). We propose a novel microarchitecture for a hybrid two layer router that supports both packetswitched communications, across its local and directional ports, as well as...

  15. Effect of Hybridized Fiber Wrapped Around the Aluminum Tubes on the Crushing Performances

    Science.gov (United States)

    Ismail, A. E.; Noranai, Z.; Mohd Nor, N. H.; Mohd Tobi, A. L.; Ahmad, M. H.

    2016-11-01

    Nowadays, synthetic fibres for an example glass fibres is frequently used to wrap the metallic tubes in order to increase their load-bearing capacity. Due to environmental considerations and non-biodegradable behaviour, natural fibres or materials are increasingly used to replace synthetic fibres. The use of synthetic fibres can be minimized by combining them with natural fibres. Based on the literature survey, combining both fibres (synthetic and natural) for crushing applications are relatively new and therefore the main work of this paper is to present the crushing performances of hybridized fibres wrapped around the aluminium tubes when subjected to quasi-static crushing forces. Glass fibres are then combined with yarn kenaf fibres according to these volume fractions: 0, 25, 50, 75 and 100%. The hybridized fibres are wrapped around the tubes twice using different orientations [0o/0o], [15°/-15°], [30o/-30o] and [45o/-45o] included empty tubes before they are immersed into polyester resin bath. The composite tubes are then quasi-statically compressed using a constant cross-head displacement of 10mm/min. The force-displacement curves for each tube conditions are recorded automatically and analysed. The relation between hybridized fibbers and fibre orientations with crashworthiness parameters are investigated and discussed associating with their crushing mechanisms.

  16. Performance Analysis of Hybrid PV/Diesel Energy System in Western Region of Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Makbul A. M. Ramli

    2014-01-01

    Full Text Available The potential implementation of hybrid photovoltaic (PV/diesel energy system in western region of Saudi Arabia is analyzed in this paper. The solar radiation intensity considered in this study is in the range of 4.15–7.17 kWh/m2/day. The HOMER software is used to perform the technical and economical analysis of the system. Three different system configurations, namely, stand-alone diesel system, and hybrid PV/diesel system with and without battery storage element, will be evaluated and discussed. The analysis will be addressed to the impact of PV penetration and battery storage on energy production, cost of energy, number of operational hours of diesel generators, fuel savings, and reduction of carbon emission for the given configurations. The simulation results indicate that the energy cost of the hybrid PV/diesel/battery system with 15% PV penetration, battery storage of 186.96 MWh, and energy demand of 32,962 MWh/day is $0.117/kWh.

  17. Energy performance of an integrated bio-and-thermal hybrid system for lignocellulosic biomass waste treatment.

    Science.gov (United States)

    Kan, Xiang; Yao, Zhiyi; Zhang, Jingxin; Tong, Yen Wah; Yang, Wenming; Dai, Yanjun; Wang, Chi-Hwa

    2017-03-01

    Lignocellulosic biomass waste, a heterogeneous complex of biodegradables and non-biodegradables, accounts for large proportion of municipal solid waste. Due to limitation of single-stage treatment, a two-stage hybrid AD-gasification system was proposed in this work, in which AD acted as pre-treatment to convert biodegradables into biogas followed by gasification converting solid residue into syngas. Energy performance of single and two-stage systems treating 3 typical lignocellulosic wastes was studied using both experimental and numerical methods. In comparison with conventional single-stage gasification treatment, this hybrid system could significantly improve the quality of produced gas for all selected biomass wastes and show its potential in enhancing total gas energy production by a maximum value of 27% for brewer's spent grain treatment at an organic loading rate (OLR) of 3gVS/L/day. The maximum overall efficiency of the hybrid system for horticultural waste treatment was 75.2% at OLR of 11.3gVS/L/day, 5.5% higher than conventional single-stage system. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Brain inspired high performance electronics on flexible silicon

    KAUST Repository

    Sevilla, Galo T.

    2014-06-01

    Brain\\'s stunning speed, energy efficiency and massive parallelism makes it the role model for upcoming high performance computation systems. Although human brain components are a million times slower than state of the art silicon industry components [1], they can perform 1016 operations per second while consuming less power than an electrical light bulb. In order to perform the same amount of computation with today\\'s most advanced computers, the output of an entire power station would be needed. In that sense, to obtain brain like computation, ultra-fast devices with ultra-low power consumption will have to be integrated in extremely reduced areas, achievable only if brain folded structure is mimicked. Therefore, to allow brain-inspired computation, flexible and transparent platform will be needed to achieve foldable structures and their integration on asymmetric surfaces. In this work, we show a new method to fabricate 3D and planar FET architectures in flexible and semitransparent silicon fabric without comprising performance and maintaining cost/yield advantage offered by silicon-based electronics.

  19. The Genomic Impacts of Drift and Selection for Hybrid Performance in Maize.

    Science.gov (United States)

    Gerke, Justin P; Edwards, Jode W; Guill, Katherine E; Ross-Ibarra, Jeffrey; McMullen, Michael D

    2015-11-01

    Although maize is naturally an outcrossing organism, modern breeding utilizes highly inbred lines in controlled crosses to produce hybrids. The U.S. Department of Agriculture's reciprocal recurrent selection experiment between the Iowa Stiff Stalk Synthetic (BSSS) and the Iowa Corn Borer Synthetic No. 1 (BSCB1) populations represents one of the longest running experiments to understand the response to selection for hybrid performance. To investigate the genomic impact of this selection program, we genotyped the progenitor lines and >600 individuals across multiple cycles of selection using a genome-wide panel of ∼40,000 SNPs. We confirmed previous results showing a steady temporal decrease in genetic diversity within populations and a corresponding increase in differentiation between populations. Thanks to detailed historical information on experimental design, we were able to perform extensive simulations using founder haplotypes to replicate the experiment in the absence of selection. These simulations demonstrate that while most of the observed reduction in genetic diversity can be attributed to genetic drift, heterozygosity in each population has fallen more than expected. We then took advantage of our high-density genotype data to identify extensive regions of haplotype fixation and trace haplotype ancestry to single founder inbred lines. The vast majority of regions showing such evidence of selection differ between the two populations, providing evidence for the dominance model of heterosis. We discuss how this pattern is likely to occur during selection for hybrid performance and how it poses challenges for dissecting the impacts of modern breeding and selection on the maize genome.

  20. Heat Removal Performance of Hybrid Control Rod for Passive In-Core Cooling System

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyung Mo; Jeong, Yeong Shin; Kim, In Guk; Bang, In Cheol [UNIST, Ulsan (Korea, Republic of)

    2015-10-15

    The two-phase closed heat transfer device can be divided by thermosyphon heat pipe and capillary wicked heat pipe which uses gravitational force or capillary pumping pressure as a driving force of the convection of working fluid. If there is a temperature difference between reactor core and ultimate heat sink, the decay heat removal and reactor shutdown is possible at any accident conditions without external power sources. To apply the hybrid control rod to the commercial nuclear power plants, its modelling about various parameters is the most important work. Also, its unique geometry is coexistence of neutron absorber material and working fluid in a cladding material having annular vapor path. Although thermosyphon heat pipe (THP) or wicked heat pipe (WHP) shows high heat transfer coefficients for limited space, the maximum heat removal capacity is restricted by several phenomena due to their unique heat transfer mechanism. Validation of the existing correlations on the annular vapor path thermosyphon (ATHP) which has different wetted perimeter and heated diameter must be conducted. The effect of inner structure, and fill ratio of the working fluid on the thermal performance of heat pipe has not been investigated. As a first step of the development of hybrid heat pipe, the ATHP which contains neutron absorber in the concentric thermosyphon (CTHP) was prepared and the thermal performance of the annular thermosyphon was experimentally studied. The heat transfer characteristics and flooding limit of the annular vapor path thermosyphon was studied experimentally to model the performance of hybrid control rod. The following results were obtained: (1) The annular vapor path thermosyphon showed better evaporation heat transfer due to the enhanced convection between adiabatic and condenser section. (2) Effect of fill ratio on the heat transfer characteristics was negligible. (3) Existing correlations about flooding limit of thermosyphon could not reflect the annular vapor

  1. Medium-energy electrons and heavy ions in Jupiter's magnetosphere - Effects of lower hybrid wave-particle interactions

    Science.gov (United States)

    Barbosa, D. D.

    1986-01-01

    A theory of medium-energy (about keV) electrons and heavy ions in Jupiter's magnetosphere is presented. Lower hybrid waves are generated by the combined effects of a ring instability of neutral wind pickup ions and the modified two-stream instability associated with transport of cool Iogenic plasma. The quasi-linear energy diffusion coefficient for lower hybrid wave-particle interactions is evaluated, and several solutions to the diffusion equation are given. Calculations based on measured wave properties show that the noise substantially modifies the particle distribution functions. The effects are to accelerate superthermal ions and electrons to keV energies and to thermalize the pickup ions on time scales comparable to the particle residence time. The S(2+)/S(+) ratio at medium energies is a measure of the relative contribution from Iogenic thermal plasma and neutral wind ions, and this important quantity should be determined from future measurements. The theory also predicts a preferential acceleration of heavy ions with an accleration time that scales inversely with the root of the ion mass. Electrons accelerated by the process contribute to further reionization of the neutral wind by electron impact, thus providing a possible confirmation of Alfven's critical velocity effect in the Jovian magnetosphere.

  2. Performance evaluation and parametric optimization of a proton exchange membrane fuel cell/heat-driven heat pump hybrid system

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X.; Chen, J. [Department of Physics, Xiamen University, Xiamen 361005 (China)

    2012-06-15

    With the help of the current models of proton exchange membrane (PEM) fuel cells and three-heat-source heat pumps, a generic model of a PEM fuel cell/heat-driven heat pump hybrid system is established, so that the waste heat produced in the PEM fuel cell may be availably utilized. Based on the theory of electrochemistry and non-equilibrium thermodynamics, expressions for the efficiency and power output of the PEM fuel cell, the coefficient of performance and rate of pumping heat of the heat-driven heat pump, and the equivalent efficiency and power output of the hybrid system are derived. The curves of the equivalent efficiency and power output of the hybrid system varying with the electric current density and the equivalent power output versus efficiency curves are represented through numerical calculation. The general performance characteristics of the hybrid system are analyzed. The optimally operating regions of some important parameters of the hybrid system are determined. The influence of some main irreversible losses on the performance of the hybrid system is discussed in detail. The advantages of the hybrid system are revealed. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Performance of Hybrids between Weedy Rice and Insect-resistant Transgenic Rice under Field Experiments: Implication for Environmental Biosafety Assessment

    Institute of Scientific and Technical Information of China (English)

    Qian-Jin Cao; Hui Xia; Xiao Yang; Bao-Rong Lu

    2009-01-01

    Transgene escape from genetically modified (GM) rice Into weedy rice via gene flow may cause undesired environmental consequences. Estimating the field performance of crop-weed hybrids will facilitate our understanding of potential introgression of crop genes (including transgenes) into weedy rice populations, allowing for effective biosafety assessment. Comparative studies of three weedy rice strains and their hybrids with two GM rice lines containing different insect-resistance transgenes (CpTl or BtlCpTI) indicated an enhanced relative performance of the crop-weed hybrids, with taller plants, more tillers, panicles, and spikelets per plant, as well as higher 1000-seed weight, compared with the weedy rice parents, although the hybrids produced less filled seeds per plant than their weedy parents. Seeds from the F1 hybrids had higher germination rates and produced more seedlings than the weedy parents, which correlated positively with 1000-seed weight. The crop-weed hybrids demonstrated a generally enhanced relative performance than their weedy rice parents in our field experiments. These findings indicate that transgenes from GM rice can persist to and introgress into weedy rice populations through recurrent crop-to-weed gene flow with the aid of slightly increased relative fitness in F1 hybrids.

  4. Performance of the hybrid wireless mesh protocol for wireless mesh networks

    DEFF Research Database (Denmark)

    Boye, Magnus; Staalhagen, Lars

    2010-01-01

    . These challenges must first be overcome before satisfactory network stability and throughput can be achieved. This paper studies the performance of the Hybrid Wireless Mesh Protocol, the proposed routing protocol for the upcoming IEEE 802.11s standard. HWMP supports two modes of path selection: reactive...... and proactive. Two scenarios of different node density are considered for both path selection modes. The results presented in this paper are based on a simulation model of the HWMP specification in the IEEE 802.11s draft 4.0 implemented in OPNET Modeler....

  5. Enhanced performance of hybrid solar cells using longer arms of quantum cadmium selenide tetrapods

    KAUST Repository

    Lee, Kyu-Sung

    2011-12-01

    We demonstrate that enhanced device performance of hybrid solar cells based on tetrapod (TP)-shaped cadmium selenide (CdSe) nanoparticles and conjugated polymer of poly (3-hexylthiophene) (P3HT) can be obtained by using longer armed tetrapods which aids in better spatial connectivity, thus decreasing charge hopping events which lead to better charge transport. Longer tetrapods with 10 nm arm length lead to improved power conversion efficiency of 1.12% compared to 0.80% of device having 5 nm short-armed tetrapods:P3HT photoactive blends.

  6. Performance of a prototype RICH detector using hybrid photo-diodes

    CERN Document Server

    Albrecht, E; Bibby, J H; Brook, N H; Duane, A; French, M; Gibson, V; Giles, R; Halley, A W; Harnew, N; John, M; Miller, D G; O'Shea, V; Teixeira-Dias, P; Smale, N J; Websdale, David M; Wilkinson, G R; Wotton, S A

    2001-01-01

    A prototype Ring-Imaging Cherenkov detector has been operated in a charged particle test beam, Cherenkov photons are imaged onto a plane of hybrid photo-diode detectors. The geometrical arrangement of the prototype and data-taking conditions are described. An analysis of the detector performance, using silica aerogel, air and C/sub 4/F/sub 10/ gas radiators, is presented. The photon yields and observed Cherenkov angle resolutions are found to be in good agreement with Monte Carlo simulation and satisfy the requirements of the RICH 1 detector in the LHCb experiment. (14 refs).

  7. Performance of a prototype RICH detector using hybrid photo-diodes

    CERN Document Server

    Albrecht, E; Billy, J H; Brook, N H; Duane, A; French, M; Gibson, V; Giles, R; Halley, A W; Harnew, N; John, M; Miller, D G; O'Shea, V; Teixeira-Dias, P; Smale, N J; Websdale, D M; Wilkinson, G; Wotton, S A

    2001-01-01

    A prototype Ring-Imaging Cherenkov detector has been operated in a charged particle test beam. Cherenkov photons are imaged onto a plane of hybrid photo-diode detectors. The geometrical arrangement of the prototype and data-taking conditions are described. An analysis of the detector performance, using silica aerogel, air and C4F10 gas radiators, is presented. The photon yields and observed angle resolutions are found to be in good agreement with Monte Carlo simulation and satisfy the requirements of the RICH-1 detector in the LHCb experiment.

  8. Parametric study and performance analysis of hybrid rocket motors with double-tube configuration

    Science.gov (United States)

    Yu, Nanjia; Zhao, Bo; Lorente, Arnau Pons; Wang, Jue

    2017-03-01

    The practical implementation of hybrid rocket motors has historically been hampered by the slow regression rate of the solid fuel. In recent years, the research on advanced injector designs has achieved notable results in the enhancement of the regression rate and combustion efficiency of hybrid rockets. Following this path, this work studies a new configuration called double-tube characterized by injecting the gaseous oxidizer through a head end injector and an inner tube with injector holes distributed along the motor longitudinal axis. This design has demonstrated a significant potential for improving the performance of hybrid rockets by means of a better mixing of the species achieved through a customized injection of the oxidizer. Indeed, the CFD analysis of the double-tube configuration has revealed that this design may increase the regression rate over 50% with respect to the same motor with a conventional axial showerhead injector. However, in order to fully exploit the advantages of the double-tube concept, it is necessary to acquire a deeper understanding of the influence of the different design parameters in the overall performance. In this way, a parametric study is carried out taking into account the variation of the oxidizer mass flux rate, the ratio of oxidizer mass flow rate injected through the inner tube to the total oxidizer mass flow rate, and injection angle. The data for the analysis have been gathered from a large series of three-dimensional numerical simulations that considered the changes in the design parameters. The propellant combination adopted consists of gaseous oxygen as oxidizer and high-density polyethylene as solid fuel. Furthermore, the numerical model comprises Navier-Stokes equations, k-ε turbulence model, eddy-dissipation combustion model and solid-fuel pyrolysis, which is computed through user-defined functions. This numerical model was previously validated by analyzing the computational and experimental results obtained for

  9. Performance Characteristics of a New Hybrid Triple Quadrupole Time-of-Flight Tandem Mass Spectrometer

    Science.gov (United States)

    Andrews, Genna L.; Simons, Brigitte L.; Young, J. Bryce; Hawkridge, Adam M.; Muddiman, David C.

    2011-01-01

    The TripleTOF 5600 System, a hybrid triple quadrupole time-of-flight mass spectrometer, was evaluated to explore the key figures of merit in generating peptide and protein identifications which included spectral acquisition rates, data quality, proteome coverage, and biological depth. Employing a Saccharomyces cerevisiae tryptic digest, careful consideration of several performance features demonstrated that the speed of the TripleTOF contributed most to the resultant data. The TripleTOF system was operated with 8, 20, and 50 MS/MS events in an effort to compare to other MS technologies and to demonstrate the abilities of the instrument platform. PMID:21619048

  10. Hybrid scheduling model and analysis of performance for switched industrial Ethernet

    Institute of Scientific and Technical Information of China (English)

    HU Chun-hua; WU Min; LIU Guo-ping; WANG Si-chun

    2007-01-01

    The fact that outburst traffic in industrial Ethernet was focused on that would bring self-similar phenomenon leading to the delay increase of the cyclical data, and a hybrid priority queue schedule model was proposed in which the outburst data was given the highest priority. Some properties of the self-similar outburst data were proved by network calculus, and its service curve scheduled by the switch was gained. And then the performance of the scheduling algorithm was obtained. The simulation results are close to those calculated by using network calculus model. Some results are of actual significance to the construction of switched industrial Ethernet.

  11. Agronomic Performance of Flue-Cured Tobacco F1 Hybrids Obtained with Different Sources of Male Sterile Cytoplasm

    Directory of Open Access Journals (Sweden)

    Berbec A

    2014-12-01

    Full Text Available Four cytoplasmic male sterile (cms F1flue-cured hybrids cv. Wiaelica × cv. Virginia Golta (VG, the male fertile analogue and the parental varieties were tested at two locations in Poland in a replicated field trial. The cms sources in the hybrids wereN. suaveolens,N. amplexicaulis,N. bigeloviiand aN. tabacumcms mutant. Under the slight to moderate pressure from black root rot present at the trial sites the hybrids showed a moderate tolerance of the disease characteristic of VG as opposed to medium strong susceptibility of Wislica. Apart from the effect of black root rot tolerance the vegetative vigor of the hybrids (plant height, leaf size, earliness was affected by cytoplasm source. The F1hybrid withN. suaveolens cytoplasm flowered approximately three days later than the remaining hybrids. Of the cms hybrids tested cmsN. bigelovii produced the tallest plants with largest mid-position leaves. Yields of cured leaves were largely influenced by black root rot and were generally higher in VG and in the hybrids than in Wislica. Leaf yields and curability were generally little affected by cms source under low pressure from black root rot. At the site with a relatively high level of black root rot infestation the yields of cmsN. suaveolens were slightly lower but the percentage of light grades slightly higher compared to those of other cms hybrids. CmsN. suaveolens was the best hybrid in terms of money returns at the low black root rot field but it was the poorest hybrid performer under high pressure from the disease. Contents of nitrogen, sugars, nicotine and ash was little affected by source of cms. There was an increased incidence of potato virus Y (PVY and white spots in cmsN. suaveolens and, to a lesser extent, in cmsN. bigelovii as compared to the remaining disease-free entries.

  12. Performance analysis of four-partition desiccant wheel and hybrid dehumidification air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jongsoo; Yamaguchi, Seiichi; Saito, Kiyoshi; Kawai, Sunao [Department of Applied Mechanics and Aerospace Engineering, School of Fundamental Science and Engineering, Waseda University, 3-4-1-58-210 Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan)

    2010-05-15

    A desiccant dehumidification system with air can decrease energy consumption because it can be driven by low-grade waste heat below 80 C. If this system can be driven by low-temperature heat sources whose temperature is below 50 C, exhausted heat from fuel cells or air conditioners that exist everywhere can be used as heat sources. This could lead to considerable energy saving. This study provides a detailed evaluation of the performance of a four-partition desiccant wheel to make a low-temperature driving heat source possible and achieve considerable energy saving by the simulation and experiment. Further, the study investigates the in-depth performance of a hybrid air-conditioning system with a four-partition desiccant wheel by simulation. As a result, it was clear that there exists an optimum rotational speed to maximize the dehumidification performance and that the hybrid air-conditioning system improves COP by approximately 94% as compared to the conventional vapour compression-type refrigerator. (author)

  13. Improved performance of hybrid error control techniques for real-time digital communications over noisy channels

    Science.gov (United States)

    Yang, Charlie Qing

    1993-06-01

    Delay-related performance characteristics are investigated for asynchronous time division multiplexing links. Two methods based on an imbedded Markov chain model are developed and applied to the system with a noisy feedback channel yielding analytical expressions for the buffer occupancy and the block delay. A recursive expression for packet loss probability for systems with a finite transmitter buffer is obtained. The concept of delay limited error control coding is introduced for real-time communications. Performance improvement by truncation of a type-2 hybrid automatic repeat-request (ARQ) protocol with one retransmission is examined showing that the truncated protocol has a bounded delay and bounded queue length under typical conditions. The error performance of the truncated protocol is further analyzed for various mobile fading channels. Matched rate hybrid error control coding for both adaptive and non-adaptive cases is also studied. A new adaptive error control protocol using Reed-Solomon codes is proposed using novel feedback transmissions to achieve faster estimation of channel states. Numerical optimization is carried out by introducing overall and modified throughput as efficiency criteria. Based on channel bit error rate measurement, optimum overall throughput is obtained with minimum implementation complexity.

  14. Interfacial electronic structure and charge transfer of hybrid graphene quantum dot and graphitic carbon nitride nanocomposites: insights into high efficiency for photocatalytic solar water splitting.

    Science.gov (United States)

    Ma, Zuju; Sa, Rongjian; Li, Qiaohong; Wu, Kechen

    2016-01-14

    New metal-free carbon nanodot/carbon nitride (C3N4) nanocomposites have shown to exhibit high efficiency for photocatalytic solar water splitting. (J. Liu, et al., Science, 2015, 347, 970) However, the mechanism underlying the ultrahigh performance of these nanocomposites and consequently the possibilities for further improvements are not at present clear. In this work, we performed hybrid functional calculations and included long-range dispersion corrections to accurately characterize the interfacial electron coupling of the graphene quantum dot-graphitic carbon nitride composites (Gdot/g-C3N4). The results revealed that the band gap of Gdot/g-C3N4 could be engineered by changing the lateral size of Gdots. In particular, the C24H12/g-C3N4 composites present an ideal band gap of 1.92 eV to harvest a large part of solar light. More interestingly, a type-II heterojunction is formed at the interface of the Gdot/g-C3N4 composites, a desirable feature for enhanced photocatalytic activity. The charge redistribution at the interface leads to strong electron depletion above the Gdot sheet and electron accumulation below the g-C3N4 monolayer, potentially facilitating the separation of H2O oxidation and reduction reactions. Furthermore, we suggested that the photocatalytic performance of the Gdot/g-C3N4 nanocomposites can be further improved by decreasing the thickness of Gdots and tuning the size of Gdots.

  15. Electron Transport Materials: Synthesis, Properties and Device Performance

    Energy Technology Data Exchange (ETDEWEB)

    Cosimbescu, Lelia; Wang, Liang; Helm, Monte L.; Polikarpov, Evgueni; Swensen, James S.; Padmaperuma, Asanga B.

    2012-06-01

    We report the design, synthesis and characterization, thermal and photophysical properties of two silane based electron transport materials, dibenzo[b,d]thiophen-2-yltriphenylsilane (Si{phi}87) and (dibenzo[b,d]thiophen-2-yl)diphenylsilane (Si{phi}88) and their performance in blue organic light emitting devices (OLEDs). The utility of these materials in blue OLEDs with iridium (III) bis[(4,6-difluorophenyl)-pyridinato-N,C']picolinate (Firpic) as the phosphorescent emitter was demonstrated. Using the silane Si{phi}87 as the electron transport material (ETm) an EQE of 18.2% was obtained, with a power efficiency of 24.3 lm/W (5.8V at 1mA/cm{sup 2}), in a heterostructure. When Si{phi}88 is used, the EQE is 18.5% with a power efficiency of 26.0 lm/W (5.5V at 1mA/cm{sup 2}).

  16. Hybrid Neural-Network: Genetic Algorithm Technique for Aircraft Engine Performance Diagnostics Developed and Demonstrated

    Science.gov (United States)

    Kobayashi, Takahisa; Simon, Donald L.

    2002-01-01

    As part of the NASA Aviation Safety Program, a unique model-based diagnostics method that employs neural networks and genetic algorithms for aircraft engine performance diagnostics has been developed and demonstrated at the NASA Glenn Research Center against a nonlinear gas turbine engine model. Neural networks are applied to estimate the internal health condition of the engine, and genetic algorithms are used for sensor fault detection, isolation, and quantification. This hybrid architecture combines the excellent nonlinear estimation capabilities of neural networks with the capability to rank the likelihood of various faults given a specific sensor suite signature. The method requires a significantly smaller data training set than a neural network approach alone does, and it performs the combined engine health monitoring objectives of performance diagnostics and sensor fault detection and isolation in the presence of nominal and degraded engine health conditions.

  17. High performance 3D printed electronics using electroless plated copper

    Science.gov (United States)

    Jian, Jin Rong; Kim, Taeil; Park, Jae Sung; Wang, Jiacheng; Kim, Woo Soo

    2017-03-01

    This paper presents design and performance validation of 3D printed electronic components, 3D toroidal air-core inductors, fabricated by multi-material based Fused Deposition Modelling (FDM) 3D printing technology and electroless copper plating. Designs of toroidal inductor is investigated with different core shapes and winding numbers; circular and half-circular cores with 10 and 13 turns of windings. Electroless plated copper thin film ensures 3D printed toroidal plastic structures to possess inductive behaviors. The inductance is demonstrated reliably with an applied source frequency from 100 kHz to 2 MHz as designs vary. An RL circuit is utilized to test the fabricated inductors' phase-leading characteristics with corresponding phase angle changes.

  18. High performance 3D printed electronics using electroless plated copper

    Directory of Open Access Journals (Sweden)

    Jin Rong Jian

    2017-03-01

    Full Text Available This paper presents design and performance validation of 3D printed electronic components, 3D toroidal air-core inductors, fabricated by multi-material based Fused Deposition Modelling (FDM 3D printing technology and electroless copper plating. Designs of toroidal inductor is investigated with different core shapes and winding numbers; circular and half-circular cores with 10 and 13 turns of windings. Electroless plated copper thin film ensures 3D printed toroidal plastic structures to possess inductive behaviors. The inductance is demonstrated reliably with an applied source frequency from 100 kHz to 2 MHz as designs vary. An RL circuit is utilized to test the fabricated inductors’ phase-leading characteristics with corresponding phase angle changes.

  19. Effect of primary electron drift on the negative ion efficiency of a volume hybrid multicusp H[sup [minus

    Energy Technology Data Exchange (ETDEWEB)

    Courteille, C.; Bruneteau, J.; Valckx, F.P.G.; Sledziewski, Z.; Bacal, M. (Laboratoire de Physique des Milieux Ionises, Laboratoire du CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France))

    1992-10-05

    A new, large, hybrid volume negative ion source is described. Observations of curvature and [ital grad] [ital B] primary electron drift in the multicusp magnetic field are reported. The direction of the electron drift changes from one filament to the neighboring one, because of the change in the direction of the magnetic field. For a given discharge current the extracted negative ion current and the plasma density at the center of the extraction region are affected by the direction of the primary electron drift of the active filaments. It was shown, however, that the negative ion current is controlled by the plasma density at the center of the extraction region. A trajectory calculation, effected in the guiding center approximation, allows to estimate the average drift velocity.

  20. Ti/Au Cathode for Electronic transport material-free organic-inorganic hybrid perovskite solar cells

    Science.gov (United States)

    Shi, Tongfei; Chen, Jian; Zheng, Jianqiang; Li, Xinhua; Zhou, Bukang; Cao, Huaxiang; Wang, Yuqi

    2016-12-01

    We have fabricated organic-inorganic hybrid perovskite solar cell that uses a Ti/Au multilayer as cathode and does not use electron transport materials, and achieved the highest power conversion efficiency close to 13% with high reproducibility and hysteresis-free photocurrent curves. Our cell has a Schottky planar heterojunction structure (ITO/PEDOT:PSS/perovskite/Ti/Au), in which the Ti insertion layer isolate the perovskite and Au layers, thus proving good contact between the Au and perovskite and increasing the cells’ shunt resistance greatly. Moreover, the Ti/Au cathode in direct contact with hybrid perovskite showed no reaction for a long-term exposure to the air, and can provide sufficient protection and avoid the perovskite and PEDOT:PSS layers contact with moisture. Hence, the Ti/Au based devices retain about 70% of their original efficiency after 300 h storage in the ambient environment.

  1. A HYBRID METHOD FOR AUTOMATIC SPEECH RECOGNITION PERFORMANCE IMPROVEMENT IN REAL WORLD NOISY ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Urmila Shrawankar

    2013-01-01

    Full Text Available It is a well known fact that, speech recognition systems perform well when the system is used in conditions similar to the one used to train the acoustic models. However, mismatches degrade the performance. In adverse environment, it is very difficult to predict the category of noise in advance in case of real world environmental noise and difficult to achieve environmental robustness. After doing rigorous experimental study it is observed that, a unique method is not available that will clean the noisy speech as well as preserve the quality which have been corrupted by real natural environmental (mixed noise. It is also observed that only back-end techniques are not sufficient to improve the performance of a speech recognition system. It is necessary to implement performance improvement techniques at every step of back-end as well as front-end of the Automatic Speech Recognition (ASR model. Current recognition systems solve this problem using a technique called adaptation. This study presents an experimental study that aims two points, first is to implement the hybrid method that will take care of clarifying the speech signal as much as possible with all combinations of filters and enhancement techniques. The second point is to develop a method for training all categories of noise that can adapt the acoustic models for a new environment that will help to improve the performance of the speech recognizer under real world environmental mismatched conditions. This experiment confirms that hybrid adaptation methods improve the ASR performance on both levels, (Signal-to-Noise Ratio SNR improvement as well as word recognition accuracy in real world noisy environment.

  2. Effect of the preparation procedure on the morphology of thin TiO₂ films and their device performance in small-molecule bilayer hybrid solar cells.

    Science.gov (United States)

    Unger, Eva L; Spadavecchia, Francesca; Nonomura, Kazuteru; Palmgren, Pål; Cappelletti, Giuseppe; Hagfeldt, Anders; Johansson, Erik M J; Boschloo, Gerrit

    2012-11-01

    Flat titanium dioxide films, to be used as the acceptor layer in bilayer hybrid solar cell devices, were prepared by spray-pyrolysis and by spin-casting. Both preparation methods resulted in anatase titania films with similar optical and electronic properties but considerably different film morphologies. Spray pyrolysis resulted in dense TiO₂ films grown onto and affected by the surface roughness of the underlying conducting glass substrates. The spin-casting preparation procedure resulted in nanoporous titania films. Hybrid solar cell devices with varying layer thickness of the small-molecule semiconducting dye TDCV-TPA were investigated. Devices built with spray-pyrolyzed titania substrates yielded conversion efficiencies up to 0.47%. Spin-cast titania substrates exhibited short circuits for thin dye layer thickness. For thicker dye layers the performance of these devices was up to 0.6% due to the higher interfacial area for charge separation of these nanoporous TiO₂ substrates.

  3. Solid amine-boranes as high performance hypergolic hybrid rocket fuels

    Science.gov (United States)

    Pfeil, Mark A.

    Hypergolic hybrid rockets have the potential of providing systems that are simple, reliable, have high performance, and allow for energy management. Such a propulsion system can be applied to fields that need a single tactical motor with flexible mission requirements of either high speed to target or extended loitering. They also provide the possibility for alternative fast response dynamic altitude control systems if ignition delays are sufficiently short. Amines are the traditional fuel of choice when selecting a hypergolic combination as these tend to react readily with both nitric acid and dinitrogen tertroxide based oxidizers. It has been found that the addition of a borane adduct to an amine fuel tends to reduce the ignition delay by up to an order of magnitude with white fuming nitric acid (WFNA). The borane addition has resulted in fuels with very short ignition delays between 2-10 ms - the fastest times for an amine based fuel reacting with nitric acid based oxidizers. The incorporation of these amine-boranes, specifically ethylenediamine bisborane (EDBB), into various fuel binders has also been found to result in ignition delays between 3-10 ms - the fastest times again for amine based fuels. It was found that the addition of a borane to an amine increased theoretical performance of the amine resulting in high performance fuels. The amine-borane/fuel binder combinations also produced higher theoretical performance values than previously used hypergolic hybrid rockets. Some of the theoretical values are on par or higher than the current toxic liquid hypergolic fuels, making amine boranes an attractive replacement. The higher performing amine-borane/fuel binder combinations also have higher performance values than the traditional rocket fuels, excluding liquid hydrogen. Thus, amine-borane based fuels have the potential to influence various area in the rocket field. An EDBB/ferrocene/epoxy fuel was tested in a hypergolic hybrid with pure nitric acid as the

  4. Performance Modeling of Hybrid MPI/OpenMP Scientific Applications on Large-scale Multicore Cluster Systems

    KAUST Repository

    Wu, Xingfu

    2011-08-01

    In this paper, we present a performance modeling framework based on memory bandwidth contention time and a parameterized communication model to predict the performance of OpenMP, MPI and hybrid applications with weak scaling on three large-scale multicore clusters: IBM POWER4, POWER5+ and Blue Gene/P, and analyze the performance of these MPI, OpenMP and hybrid applications. We use STREAM memory benchmarks to provide initial performance analysis and model validation of MPI and OpenMP applications on these multicore clusters because the measured sustained memory bandwidth can provide insight into the memory bandwidth that a system should sustain on scientific applications with the same amount of workload per core. In addition to using these benchmarks, we also use a weak-scaling hybrid MPI/OpenMP large-scale scientific application: Gyro kinetic Toroidal Code in magnetic fusion to validate our performance model of the hybrid application on these multicore clusters. The validation results for our performance modeling method show less than 7.77% error rate in predicting the performance of hybrid MPI/OpenMP GTC on up to 512 cores on these multicore clusters. © 2011 IEEE.

  5. Organic-inorganic hybrid lead halide perovskites for optoelectronic and electronic applications.

    Science.gov (United States)

    Zhao, Yixin; Zhu, Kai

    2016-02-07

    Organic and inorganic hybrid perovskites (e.g., CH(3)NH(3)PbI(3)), with advantages of facile processing, tunable bandgaps, and superior charge-transfer properties, have emerged as a new class of revolutionary optoelectronic semiconductors promising for various applications. Perovskite solar cells constructed with a variety of configurations have demonstrated unprecedented progress in efficiency, reaching about 20% from multiple groups after only several years of active research. A key to this success is the development of various solution-synthesis and film-deposition techniques for controlling the morphology and composition of hybrid perovskites. The rapid progress in material synthesis and device fabrication has also promoted the development of other optoelectronic applications including light-emitting diodes, photodetectors, and transistors. Both experimental and theoretical investigations on organic-inorganic hybrid perovskites have enabled some critical fundamental understandings of this material system. Recent studies have also demonstrated progress in addressing the potential stability issue, which has been identified as a main challenge for future research on halide perovskites. Here, we review recent progress on hybrid perovskites including basic chemical and crystal structures, chemical synthesis of bulk/nanocrystals and thin films with their chemical and physical properties, device configurations, operation principles for various optoelectronic applications (with a focus on solar cells), and photophysics of charge-carrier dynamics. We also discuss the importance of further understanding of the fundamental properties of hybrid perovskites, especially those related to chemical and structural stabilities.

  6. Performance Analysis of High-Speed Deep/Shallow Recessed Hybrid Bearing

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2013-01-01

    Full Text Available The present paper proposes a theoretical analysis of the performance of deep/shallow recessed hybrid bearing. It is intended that, on the basis of the numerical results drawn from this study, appropriate shallow recess depth and width can be determined for use in the bearing design process. By adopting bulk flow theory, the turbulent Reynolds equation and energy equation are modified and solved numerically including concentrated inertia effects at the recess edge with different depth and width of shallow recess. The results indicate that the load capacity, drag torque increases as the depth of shallow recess is shallower and the width ratio (half angle of deep recess versus half angle of shallow recess is smaller. In contrast, the flow rate decreases as the depth of shallow recess is shallower and the width ratio is smaller. Nevertheless, the appropriate design of the depth and width of shallow recess might well induce the performance of high-speed deep/shallow recessed hybrid bearing.

  7. Performance analysis of a liquid desiccant and membrane contactor hybrid air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Bergero, Stefano; Chiari, Anna [DIPARC, Faculty of Architecture, University of Genoa, Stradone S. Agostino 37, 16123 Genova (Italy)

    2010-11-15

    The present study examines the performances of a hybrid air-conditioning system in which a vapour-compression inverse cycle is integrated with an air dehumidification system working with hygroscopic solution and hydrophobic membrane. This model may be a valid alternative to traditional summertime air-conditioning system, in which the air is cooled to below its dew-point temperature and subsequently reheated. The proposed hybrid system involves simultaneously cooling and dehumidifying the air conveyed to the conditioned ambient in an air-solution membrane contactor. An LiCl solution is cooled by means of a vapour-compression inverse cycle using the refrigerant KLEA 407C. The solution is regenerated in another membrane contactor by exploiting the heat rejected by the condenser. A SIMULINK calculation programme was designed in order to simulate the system under examination in steady-state conditions. The performances of the system were analysed on varying a few significant operating parameters, and were compared with those of a traditional direct-expansion air-conditioning plant in typical summertime conditions. The results of the simulations revealed significant energy savings, which, in particular operating conditions, may exceed 50%. (author)

  8. Study on Absorption and Regeneration Performance of Novel Hybrid Solutions for CO2 Capture

    Institute of Scientific and Technical Information of China (English)

    Gao Jie; Yin Jun; Zhu Feifei; Chen Xin; Tong Ming; Kang Wanzhong; Zhou Yanbo; Lu Jun

    2016-01-01

    Recently, a kind of hybrid solution MEA-methanol shows a better CO2 capture performance over aqueous MEA solution. However, the vaporization of methanol is the biggest disadvantage that hinders its application, so it is necessary to minimize the vaporization of methanol during both the absorption and regeneration processes. In this work, two kinds of hybrid solutions were studied and compared with aqueous MEA solution and MEA-methanol solution, including MEA/TEA/methanol solution and MEA/glycerol/methanol solution. The absorption property of MEA/glycerol/methanol solution is better than aqueous MEA solution within a certain period of time and the absorption property of MEA/TEA/methanol solution is too poor to be used in CO2 capture. By increasing the concentration of TEA and decreasing the concentration of MEA, the absorption rate, CO2 capture efifciency and absorption capacity all decreased. Upon adding glycerol, the cyclic capacity decreased and the generation temperature increased, and moreover, the density and viscosity also increased considerably. So after adding TEA and glycerol, the CO2 capture performance of MEA-methanol solvent cannot be improved.

  9. Power Management Strategy of Hybrid Electric Vehicles Based on Quadratic Performance Index

    Directory of Open Access Journals (Sweden)

    Chaoying Xia

    2015-11-01

    Full Text Available An energy management strategy (EMS considering both optimality and real-time performance has become a challenge for the development of hybrid electric vehicles (HEVs in recent years. Previous EMSes based on the optimal control theory minimize the fuel consumption, but cannot be directly implemented in real-time because of the requirement for a prior knowledge of the entire driving cycle. This paper presents an innovative design concept and method to obtain a power management strategy for HEVs, which is independent of future driving conditions. A quadratic performance index is designed to ensure the vehicle drivability, maintain the battery energy sustainability and average and smooth the engine power and motor power to indirectly reduce fuel consumption. To further improve the fuel economy, two rules are adopted to avoid the inefficient engine operation by switching control modes between the electric and hybrid modes according to the required driving power. The derived power of the engine and motor are related to current vehicle velocity and battery residual energy, as well as their desired values. The simulation results over different driving cycles in Advanced Vehicle Simulator (ADVISOR show that the proposed strategy can significantly improve the fuel economy, which is very close to the optimal strategy based on Pontryagin’s minimum principle.

  10. Effect of grain port length-diameter ratio on combustion performance in hybrid rocket motors

    Science.gov (United States)

    Cai, Guobiao; Zhang, Yuanjun; Tian, Hui; Wang, Pengfei; Yu, Nanjia

    2016-11-01

    The objectives of this study are to develop a more accurate regression rate considering the oxidizer mass flow and the fuel grain geometry configuration with numerical and experimental investigations in polyethylene (PE)/90% hydrogen peroxide (HP) hybrid rocket. Firstly, a 2-D axisymmetric CFD model with turbulence, chemistry reaction, solid-gas coupling is built to investigate the combustion chamber internal flow structure. Then a more accurate regression formula is proposed and the combustion efficiency changing with the length-diameter ratio is studied. A series experiments are conducted in various oxidizer mass flow to analyze combustion performance including the regression rate and combustion efficiency. The regression rates are measured by the fuel mass reducing and diameter changing. A new regression rate formula considering the fuel grain configuration is proposed in this paper. The combustion efficiency increases with the length-diameter ratio changing. To improve the performance of a hybrid rocket motor, the port length-diameter ratio is suggested 10-12 in the paper.

  11. Performance Assessment of a Hybrid Solar-Geothermal Air Conditioning System for Residential Application: Energy, Exergy, and Sustainability Analysis

    Directory of Open Access Journals (Sweden)

    Yasser Abbasi

    2016-01-01

    Full Text Available This paper investigates the performance of a ground source heat pump that is coupled with a photovoltaic system to provide cooling and heating demands of a zero-energy residential building. Exergy and sustainability analyses have been conducted to evaluate the exergy destruction rate and SI of different compartments of the hybrid system. The effects of monthly thermal load variations on the performance of the hybrid system are investigated. The hybrid system consists of a vertical ground source heat exchanger, rooftop photovoltaic panels, and a heat pump cycle. Exergetic efficiency of the solar-geothermal heat pump system does not exceed 10 percent, and most exergy destruction takes place in photovoltaic panel, condenser, and evaporator. Although SI of PV system remains constant during a year, SI of GSHP varies depending on cooling and heating mode. The results also show that utilization of this hybrid system can reduce CO2 emissions by almost 70 tons per year.

  12. Driving electrocatalytic activity by interface electronic structure control in a metalloprotein hybrid catalyst for efficient hydrogen evolution.

    Science.gov (United States)

    Behera, Sushant Kumar; Deb, Pritam; Ghosh, Arghya

    2016-08-17

    The rational design of metalloprotein hybrid structures and precise calculations for understanding the role of the interfacial electronic structure in regulating the HER activity of water splitting sites and their microscopic effect for obtaining robust hydrogen evolution possess great promise for developing highly efficient nano-bio hybrid HER catalysts. Here, we employ high-accuracy linear-scaling density functional theory calculations using a near-complete basis set and a minimal parameter implicit solvent model within the self-consistent calculations, on silver (Ag) ions assimilated on bacteriorhodopsin (bR) at specific binding sites. Geometry optimization indicates the formation of active sites at the interface of the metalloprotein complex and the density of states reflects the metallic nature of the active sites. The reduced value of the canonical orbital gap indicates the state of dynamic nature after Ag ion assimilation on active sites and smooth electron transfer. These incorporated active protein sites are more efficient in electrolytic splitting of water than pristine sites due to their low value of Gibbs free energy for the HER in terms of hydrogen coverages. Volcano plot analysis and the free energy diagram are compared for understanding the hydrogen evolution efficiency. Moreover, the essential role of the interfacial electronic properties in regulating the HER catalytic activity of water splitting sites and enhancing the efficiency is elucidated.

  13. Applications of the Hybrid Theory to the Scattering of Electrons from HE+ and Li++ and Resonances in these Systems

    Science.gov (United States)

    Bhatia, Anand K.

    2008-01-01

    Applications of the hybrid theory to the scattering of electrons from Ile+ and Li++ and resonances in these systems, A. K. Bhatia, NASA/Goddard Space Flight Center- The Hybrid theory of electron-hydrogen elastic scattering [I] is applied to the S-wave scattering of electrons from He+ and Li++. In this method, both short-range and long-range correlations are included in the Schrodinger equation at the same time. Phase shifts obtained in this calculation have rigorous lower bounds to the exact phase shifts and they are compared with those obtained using the Feshbach projection operator formalism [2], the close-coupling approach [3], and Harris-Nesbet method [4]. The agreement among all the calculations is very good. These systems have doubly-excited or Feshbach resonances embedded in the continuum. The resonance parameters for the lowest ' S resonances in He and Li+ are calculated and they are compared with the results obtained using the Feshbach projection operator formalism [5,6]. It is concluded that accurate resonance parameters can be obtained by the present method, which has the advantage of including corrections due to neighboring resonances and the continuum in which these resonances are embedded.

  14. ORNL TNS program: microwave start-up of tokamak plasmas near electron cyclotron and upper hybrid resonances

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Y. K.M.; Borowski, S. K.

    1977-12-01

    The scenario of toroidal plasma start-up with microwave initiation and heating near the electron cyclotron frequency is suggested and examined here. We assume microwave irradiation from the high field side and an anomalously large absorption of the extraordinary waves near the upper hybrid resonance. The dominant electron energy losses are assumed to be due to magnetic field curvature and parallel drifts, ionization of neutrals, cooling by ions, and radiation by low Z impurities. It is shown by particle and energy balance considerations that electron temperatures around 250 eV and densities of 10/sup 12/ to 10/sup 13/ cm/sup -3/ can be maintained, at least in a narrow region near the upper hybrid resonance, with modest microwave powers in the Impurity Study Experiment (ISX) (120 kW at 28 GHz) and The Next Step (TNS) (0.57 MW at 120 GHz). The loop voltages required for start-up from these initial plasmas are also estimated. It is shown that the loop voltage can be reduced by a factor of five to ten from that for unassisted start-up without an increase in the resistive loss in volt-seconds. If this reduction in loop voltage is verified in the ISX experiments, substantial savings in the cost of power supplies for the ohmic heating (OH) and equilibrium field (EF) coils can be realized in future large tokamaks.

  15. Controlled growth of carbon nanotube-graphene hybrid materials for flexible and transparent conductors and electron field emitters.

    Science.gov (United States)

    Nguyen, Duc Dung; Tai, Nyan-Hwa; Chen, Szu-Ying; Chueh, Yu-Lun

    2012-01-21

    We report a versatile synthetic process based on rapid heating and cooling chemical vapor deposition for the growth of carbon nanotube (CNT)-graphene hybrid materials where the thickness of graphene and density of CNTs are properly controlled. Graphene films are demonstrated as an efficient barrier layer for preventing poisoning of iron nanoparticles, which catalyze the growth of CNTs on copper substrates. Based on this method, the opto-electronic and field emission properties of graphene integrated with CNTs can be remarkably tailored. A graphene film exhibits a sheet resistance of 2.15 kΩ sq(-1) with a transmittance of 85.6% (at 550 nm), while a CNT-graphene hybrid film shows an improved sheet resistance of 420 Ω sq(-1) with an optical transmittance of 72.9%. Moreover, CNT-graphene films are demonstrated as effective electron field emitters with low turn-on and threshold electric fields of 2.9 and 3.3 V μm(-1), respectively. The development of CNT-graphene films with a wide range of tunable properties presented in this study shows promising applications in flexible opto-electronic, energy, and sensor devices.

  16. 3D electrostatic gyrokinetic electron and fully kinetic ion simulation of lower-hybrid drift instability of Harris current sheet

    Science.gov (United States)

    Wang, Zhenyu; Lin, Yu; Wang, Xueyi; Tummel, Kurt; Chen, Liu

    2016-07-01

    The eigenmode stability properties of three-dimensional lower-hybrid-drift-instabilities (LHDI) in a Harris current sheet with a small but finite guide magnetic field have been systematically studied by employing the gyrokinetic electron and fully kinetic ion (GeFi) particle-in-cell (PIC) simulation model with a realistic ion-to-electron mass ratio mi/me . In contrast to the fully kinetic PIC simulation scheme, the fast electron cyclotron motion and plasma oscillations are systematically removed in the GeFi model, and hence one can employ the realistic mi/me . The GeFi simulations are benchmarked against and show excellent agreement with both the fully kinetic PIC simulation and the analytical eigenmode theory. Our studies indicate that, for small wavenumbers, ky, along the current direction, the most unstable eigenmodes are peaked at the location where k →.B → =0 , consistent with previous analytical and simulation studies. Here, B → is the equilibrium magnetic field and k → is the wavevector perpendicular to the nonuniformity direction. As ky increases, however, the most unstable eigenmodes are found to be peaked at k →.B → ≠0 . In addition, the simulation results indicate that varying mi/me , the current sheet width, and the guide magnetic field can affect the stability of LHDI. Simulations with the varying mass ratio confirm the lower hybrid frequency and wave number scalings.

  17. Cooling Performance Evaluation of the Hybrid Heat Pipe for Spent Nuclear Fuel Dry Storage Cask

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Yeong Shin; Bang, In Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    To evaluate the concept of the cooling device, 2-step CFD analysis was conducted for the cooling performance of hybrid heat pipe, which consists of single fuel assembly model and full scope dry cask model. As a passive cooling device of the metal cask for dry storage of spent nuclear fuel, hybrid heat pipe was applied to DPC developed in Korea. Hybrid heat pipe is the heat pipe containing neutron absorber can be used as a passive cooling in nuclear application with both decay heat removal and control the reactivity. In this study, 2-step CFD analysis was performed to find to evaluate the heat pipe-based passive cooling system for the application to the dry cask. Only spent fuel pool cannot satisfy the demands for high burnup fuel and large amount of spent fuel. Therefore, it is necessary to prepare supplement of the storage facilities. As one of the candidate of another type of storage, dry storage method have been preferred due to its good expansibility of storage capacity and easy long-term management. Dry storage uses the gas or air as coolant with passive cooling and neutron shielding materials was used instead of water in wet storage system. It is relatively safe and emits little radioactive waste for the storage. As short term actions for the limited storage capacity of spent fuel pool, it is considered to use dry interim/long term storage method to increase the capacity of spent nuclear fuel storage facilities. For 10-year cooled down spent fuel in the pool storage, fuel rod temperature inside metal cask is expected over 250 .deg. C in simulation. Although it satisfied the criteria that cladding temperature of the spent fuel should keep under 400 .deg. C during storage period, high temperature inside cask can accelerate the thermal degradation of the structural materials consisting metal cask and fuel assembly as well as limitation of the storage capacity of metal cask. In this paper, heat pipe-based cooling device for the dry storage cask was suggested for

  18. Extending the Performance of Hybrid NoCs beyond the Limitations of Network Heterogeneity

    Directory of Open Access Journals (Sweden)

    Michael Opoku Agyeman

    2017-04-01

    Full Text Available To meet the performance and scalability demands of the fast-paced technological growth towards exascale and big data processing with the performance bottleneck of conventional metal-based interconnects (wireline, alternative interconnect fabrics, such as inhomogeneous three-dimensional integrated network-on-chip (3D NoC and hybrid wired-wireless network-on-chip (WiNoC, have emanated as a cost-effective solution for emerging system-on-chip (SoC design. However, these interconnects trade off optimized performance for cost by restricting the number of area and power hungry 3D routers and wireless nodes. Moreover, the non-uniform distributed traffic in a chip multiprocessor (CMP demands an on-chip communication infrastructure that can avoid congestion under high traffic conditions while possessing minimal pipeline delay at low-load conditions. To this end, in this paper, we propose a low-latency adaptive router with a low-complexity single-cycle bypassing mechanism to alleviate the performance degradation due to the slow 2D routers in such emerging hybrid NoCs. The proposed router transmits a flit using dimension-ordered routing (DoR in the bypass datapath at low-loads. When the output port required for intra-dimension bypassing is not available, the packet is routed adaptively to avoid congestion. The router also has a simplified virtual channel allocation (VA scheme that yields a non-speculative low-latency pipeline. By combining the low-complexity bypassing technique with adaptive routing, the proposed router is able to balance the traffic in hybrid NoCs to achieve low-latency communication under various traffic loads. Simulation shows that the proposed router can reduce applications’ execution time by an average of 16.9% compared to low-latency routers, such as SWIFT. By reducing the latency between 2D routers (or wired nodes and 3D routers (or wireless nodes, the proposed router can improve the performance efficiency in terms of average

  19. Low-temperature electronic transport in one-dimensional hybrid systems: Metal cluster embedded carbon nanotubes

    Science.gov (United States)

    Soldano, Caterina

    The investigation of the electronic and magnetotransport properties at low temperature in individual MWNT with embedded clusters are here presented. The majority of studies of transport in MWNT reported in literature has been carried out on arc-discharge grown tubes, generally considered "clean" and defect-free. In this project, individual MWNT grown in alumina template are used; these tubes are highly disordered compared for example to arc-discharge ones, conditions that dramatically will impact the charge transport. As-fabricated devices are in general highly resistive. A large decrease in the value of the device resistance can be achieved through a controlled and fast high-bias sweep method (HBT) across the sample. Scanning electron microscopy analysis shows that this method induces a metal (platinum) decoration of the MWNT surface as a consequence of the large amount of Joule heating developed during the sweep. Temperature dependence study (5wires. DFT calculations show that the enhancement in conductance can be explained in term of enhanced density of states around the Fermi energy due to presence of platinum on the wall. Magneto-transport measurements carried out up to a value of magnetic field up to |5|T show a clear dependence from the energy (i.e. applied bias). A nearly symmetric and monotonically increasing positive magneto-conductance is observed in the range of the applied field, confirming the presence of weak localization in the system. A small but distinct Rashba spin-orbit scattering effect in the magneto-conductance in the low-field regime (|B|<.5T) is found and attributed to the surface decoration. Electronic and magnetotransport measurements independently confirm the 1D nature of the transport in the system. "Zero-field" measurements were performed on magnetic cluster-embedded MWNT-based devices (FM-MWNT). Temperature dependence of the conductance reveals a Luttinger liquid type of behavior in the range of investigated temperatures but no

  20. Overview of initial research into the effects of strong vortex flow on hybrid rocket combustion and performance

    Science.gov (United States)

    Gloyer, P.; Knuth, William H.; Goodman, J.

    1993-01-01

    An examination of the effect of vortex flow on hybrid rocket combustion and performance is underway. Emphasis is on response of the fuel regression rate when subjected to vortex flow. Initial results show that there is a definite effect of the vortex on fuel regression rate. Future work will focus on quantitatively measuring this regression rate. This work is part of an overall program to develop an ultra low cost fuel system for hybrid rocket engines.

  1. Graphene oxide-polythiophene derivative hybrid nanosheet for enhancing performance of supercapacitor

    Science.gov (United States)

    Alabadi, Akram; Razzaque, Shumaila; Dong, Zehua; Wang, Weixing; Tan, Bien

    2016-02-01

    S-doped graphene oxide hybrid nanosheets are prepared by a facile in situ-polymerization method. The electrochemical performance is evaluated using cyclic voltammetry, galvanostatic charge/discharge techniques and impedance spectroscopy in 2 M KOH. As an electroactive material, it exhibits good capacitive performance in alkali aqueous electrolyte, high specific capacitance (up to 296 F g-1) at a current density of 0.3 A g-1, which is calculated via charge/discharge curve in three electrode systems. The electrical conductivity is also measured. More importantly, over 91.86% of the long-term stability is retained after repeating the galvanostatic charge/discharge over 4000 cycles. Furthermore, larger energy density (up to 148 W h kg-1 at a power density of 41.6 W kg-1) of the GO-TB-based three-electrode device is obtained with alkali aqueous electrolytes.

  2. Performance study of new pixel hybrid photon detector prototypes for the LHCb RICH counters

    CERN Document Server

    Moritz, M; Allebone, L; Campbell, M; Gys, Thierry; Newby, C; Pickford, A; Piedigrossi, D; Wyllie, K

    2004-01-01

    A pixel Hybrid Photon Detector was developed according to the specific requirements of the LHCb ring imaging Cerenkov counters. This detector comprises a silicon pixel detector bump-bonded to a binary readout chip to achieve a 25 ns fast readout and a high signal-to-noise ratio. The detector performance was characterized by varying the pixel threshold, the tube high voltage, the silicon bias voltage and by the determination of the photoelectron detection efficiency. Furthermore accelerated aging and high pixel occupancy tests were performed to verify the long term stability. The results were obtained using Cerenkov light and a fast pulsed light emitting diode. All measurements results are within the expectations and fulfill the design goals. (8 refs).

  3. Unified performance analysis of hybrid-ARQ with incremental redundancy over free-space optical channels

    KAUST Repository

    Zedini, Emna

    2014-09-01

    In this paper, we carry out a unified performance analysis of hybrid automatic repeat request (HARQ) with incremental redundancy (IR) from an information theoretic perspective over a point-to-point free-space optical (FSO) system. First, we introduce a novel unified expression for the distribution of a single FSO link modeled by the Gamma fading that accounts for pointing errors subject to both types of detection techniques at the receiver side (i.e. heterodyne detection and intensity modulation with direct detection (IM/DD)). Then, we provide analytical expressions for the outage probability, the average number of transmissions, and the average transmission rate for HARQ with IR, assuming a maximum number of rounds for the HARQ protocol. In our study, the communication rate per HARQ round is constant. Our analysis demonstrates the importance of HARQ in improving the performance and reliability of FSO communication systems. All the given results are verified via computer-based Monte-Carlo simulations.

  4. Performance Evaluation of Conventional and Hybrid Feature Extractions Using Multivariate HMM Classifier

    Directory of Open Access Journals (Sweden)

    Veton Z. Këpuska

    2015-04-01

    Full Text Available Speech feature extraction and likelihood evaluation are considered the main issues in speech recognition system. Although both techniques were developed and improved, but they remain the most active area of research. This paper investigates the performance of conventional and hybrid speech feature extraction algorithm of Mel Frequency Cepstrum Coefficient (MFCC, Linear Prediction Cepstrum Coefficient (LPCC, perceptual linear production (PLP and RASTA-PLP through using multivariate Hidden Markov Model (HMM classifier. The performance of the speech recognition system is evaluated based on word error rate (WER, which is given for different data set of human voice using isolated speech TIDIGIT corpora sampled by 8 Khz. This data includes the pronunciation of eleven words (zero to nine plus oh are recorded from 208 different adult speakers (men & women each person uttered each word 2 times.

  5. Performing Hybrid Recommendation in Intermodal Transportation-the FTMarket System's Recommendation Module

    CERN Document Server

    Lazanas, Alexis

    2009-01-01

    Diverse recommendation techniques have been already proposed and encapsulated into several e-business applications, aiming to perform a more accurate evaluation of the existing information and accordingly augment the assistance provided to the users involved. This paper reports on the development and integration of a recommendation module in an agent-based transportation transactions management system. The module is built according to a novel hybrid recommendation technique, which combines the advantages of collaborative filtering and knowledge-based approaches. The proposed technique and supporting module assist customers in considering in detail alternative transportation transactions that satisfy their requests, as well as in evaluating completed transactions. The related services are invoked through a software agent that constructs the appropriate knowledge rules and performs a synthesis of the recommendation policy.

  6. Comparisons of yield performance and nitrogen response between hybrid and inbred rice under different ecological conditions in southern China

    Institute of Scientific and Technical Information of China (English)

    JIANG Peng; XIONG Hong; ZOU Ying-bin; XIE Xiao-bing; HUANG Min; ZHOU Xue-feng; ZHANG Rui-chun; CHEN Jia-na; WU Dan-dan; XIA Bing; XU Fu-xian

    2015-01-01

    In order to understand the yield performance and nitrogen (N) response of hybrid rice under different ecological conditions in southern China, ifeld experiments were conducted in Huaiji County of Guangdong Province, Binyang of Guangxi Zhuang Autonomous Region and Changsha City of Hunan Province, southern China in 2011 and 2012. Two hybrid (Liangyoupeijiu and Y-liangyou 1) and two inbred rice cultivars (Yuxiangyouzhan and Huanghuazhan) were grown under three N treatments (N1, 225 kg ha–1;N2, 112.5–176 kg ha–1;N3, 0 kg ha–1) in each location. Results showed that grain yield was higher in Changsha than in Huaiji and Binyang for both hybrid and inbred cultivars. The higher grain yield in Changsha was attribut-ed to larger panicle size (spikelets per panicle) and higher biomass production. Consistently higher grain yield in hybrid than in inbred cultivars was observed in Changsha but not in Huaiji and Binyang. Higher grain weight and higher biomass production were responsible for the higher grain yield in hybrid than in inbred cultivars in Changsha. The better crop perfor-mance of rice (especial y hybrid cultivars) in Changsha was associated with its temperature conditions and indigenous soil N. N2 had higher internal N use efifciency, recovery efifciency of applied N, agronomic N use efifciency, and partial factor productivity of applied N than N1 for both hybrid and inbred cultivars, while the difference in grain yield between N1 and N2 was relatively smal . Our study suggests that whether hybrid rice can outyield inbred rice to some extent depends on the ecological conditions, and N use efifciency can be increased by using improved nitrogen management such as site-speciifc N management in both hybrid and inbred rice production.

  7. Study of the hybrid controller electronics for the nano-stabilization of mechanical vibrations of CLIC quadrupoles

    CERN Document Server

    Fernandez Carmona, P; Collette, C; Esposito, M; Guinchard, M; Janssens, S; Kuzmin, A; Moron Ballester, R

    2011-01-01

    In order to achieve the required levels of luminosity in the CLIC linear collider, mechanical stabilization of quadrupoles to the nanometre level is required. The paper describes a design of hybrid electronics combining an analogue controller and digital communication with the main machine controller. The choice of local analogue control ensures the required low latency while still keeping sufficiently low noise level. Furthermore, it reduces the power consumption, rack space and cost. Sensitivity to radiation single events upsets is reduced compared to a digital controller. The digital part is required for fine tuning and real time monitoring via digitization of critical parameters.

  8. Presentation and Performance Evaluation of a Novel Stator-Permanent-Magnet Hybrid Stepping Motor

    Directory of Open Access Journals (Sweden)

    Binglin Lu

    2017-05-01

    Full Text Available In this paper, a new type of hybrid stepping motor (HSM with permanent magnets (PMs embedded in the stator, namely the stator-permanent-magnet hybrid stepping motor (SHSM, is presented. It has the same operation principles as the traditional HSM, with a 2-D distributed magnetic field nature and superiorities such as simpler rotor structure, easier PM cooling, higher torque and power density, and higher power grade. Its structural topology and operation principles are initially presented. Then an investigation on the performance comparison between the HSM and the SHSM, in terms of PM flux density, PM torque, detent torque, positional holding accuracy, stator core saturation issue, PM flux leakage, and PM utilization rate is carried out theoretically to make an assessment of the performance superiorities of the SHSM. A prototype of a 2-phase 8-pole 50-rotor-tooth SHSM is fabricated and experimentally compared with the HSM by using finite element analysis (FEA to verify the motor’s operational feasibility and the theoretical analysis. The FEA and experimental results show that the proposed SHSM has performance advantages such as higher torque density, higher power grade, and higher pull-out torque, holding torque, and torque-speed property, although it has performance defects such as higher torque ripple and relatively lower positional holding accuracy in the open-loop operation than the conventional HSM. Consequently, this novel SHSM is more suitable for electromechanical energy conversion applications rather than positioning mechanisms, especially taking into account the open-loop control advantage.

  9. Performance Analysis of Hybrid WDM-FSO System under Various Weather Conditions

    Science.gov (United States)

    Robinson, S.; Jasmine, S.

    2016-09-01

    Free Space Optical (FSO) communication is being realized as an effective solution for future accessing networks, offering light passed through air. The performance of FSO system can be primarily degraded by various atmospheric attenuations such as rain, fog, haze and snow. At present, hybridization of Dense Wavelength Division Multiplexing (DWDM) with Coarse Wavelength Division Multiplexing (CWDM) becomes necessary to scale the speed and high bandwidth of the services. In this paper, primarily the attenuation values for different weather conditions are calculated. Then the hybrid WDM-FSO system is proposed, designed and the network parameters such as Bit Error Rate (BER), Quality factor (Q factor) and receiver sensitivity are analyzed with respect to link distance for various weather conditions. For investigation, four CWDM (1,510 nm, 1,530 nm, 1,570 nm and 1,570 nm) channel and eight DWDM channels (1,537.4 nm, 1,538.2 nm, 1,539 nm, 1,539.8 nm, 1,540.6 nm, 1,541.4 nm, 1,542.2 nm and 1,543 nm) are considered whose corresponding channel spacing is 20 nm and 0.8 nm, respectively. In addition, the Erbium Doped Fiber Amplifier (EDFA) is inserted at the receiver end in order to enhance the link distance. The proposed hybrid WDM-FSO system is designed to handle the quality of transmission for 12 users, each at a data rate of 2.5 Gbps along an FSO link distance of about 960 km.

  10. A Hybrid MCDM Model for Improving the Electronic Health Record to Better Serve Client Needs

    Directory of Open Access Journals (Sweden)

    James J. H. Liou

    2017-10-01

    Full Text Available Although the electronic health record (EHR is a promising innovation in the healthcare industry, the implementation of EHR has been relatively slow. A theoretical structure for the exploration and improvement of this usage of EHR is proposed. Incorporating the theoretical structure of TOE (technology-organization-environment, we apply the DEMATEL (decision-making trial and evaluation laboratory technique to illustrate the influence-matrix and to construct the INRM (influential network relationship map. Based on this DEMATEL influence matrix and the fundamental concepts of ANP (Analytic Hierarchy Process, we derive influential weights for the criteria. These influential weights are then combined with the modified VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje method to find ways to understand and enhance the usage of EHR technology. The outcome demonstrates that our model can not only be used for implementation of EHR technology, but can also be applied to analyze the gaps in performance between the aspiration level and present performance values in individual criterion/dimension.

  11. The Digital electronic Guideline Library (DeGeL): a hybrid framework for representation and use of clinical guidelines.

    Science.gov (United States)

    Shahar, Yuval; Young, Ohad; Shalom, Erez; Mayaffit, Alon; Moskovitch, Robert; Hessing, Alon; Galperin, Maya

    2004-01-01

    We propose to present a poster (and potentially also a demonstration of the implemented system) summarizing the current state of our work on a hybrid, multiple-format representation of clinical guidelines that facilitates conversion of guidelines from free text to a formal representation. We describe a distributed Web-based architecture (DeGeL) and a set of tools using the hybrid representation. The tools enable performing tasks such as guideline specification, semantic markup, search, retrieval, visualization, eligibility determination, runtime application and retrospective quality assessment. The representation includes four parallel formats: Free text (one or more original sources); semistructured text (labeled by the target guideline-ontology semantic labels); semiformal text (which includes some control specification); and a formal, machine-executable representation. The specification, indexing, search, retrieval, and browsing tools are essentially independent of the ontology chosen for guideline representation, but editing the semi-formal and formal formats requires ontology-specific tools, which we have developed in the case of the Asbru guideline-specification language. The four formats support increasingly sophisticated computational tasks. The hybrid guidelines are stored in a Web-based library. All tools, such as for runtime guideline application or retrospective quality assessment, are designed to operate on all representations. We demonstrate the hybrid framework by providing examples from the semantic markup and search tools.

  12. Ultrafast electron transfer from low band gap conjugated polymer to quantum dots in hybrid photovoltaic materials

    Science.gov (United States)

    Couderc, Elsa; Greaney, Matthew J.; Thornbury, William; Brutchey, Richard L.; Bradforth, Stephen E.

    2014-09-01

    Ultrafast transient absorption spectroscopy is used in conjunction with chemical doping experiments to study the photo-generation of charges in hybrid thin films composed of PCPDTBT and CdSe quantum dots. We show how we use chemical doping experiments to de-convolute the spectral signatures of the transient states in the near infrared.

  13. Understanding the electronic structure of CdSe quantum dot-fullerene (C60) hybrid nanostructure for photovoltaic applications

    Science.gov (United States)

    Sarkar, Sunandan; Rajbanshi, Biplab; Sarkar, Pranab

    2014-09-01

    By using the density-functional tight binding method, we studied the electronic structure of CdSe quantum dot(QD)-buckminsterfullerene (C60) hybrid systems as a function of both the size of the QD and concentration of the fullerene molecule. Our calculation reveals that the lowest unoccupied molecular orbital energy level of the hybrid CdSeQD-C60 systems lies on the fullerene moiety, whereas the highest occupied molecular orbital (HOMO) energy level lies either on the QD or the fullerene depending on size of the CdSe QD. We explored the possibility of engineering the energy level alignment by varying the size of the CdSe QD. With increase in size of the QD, the HOMO level is shifted upward and crosses the HOMO level of the C60-thiol molecule resulting transition from the type-I to type-II band energy alignment. The density of states and charge density plot support these types of band gap engineering of the CdSe-C60 hybrid systems. This type II band alignment indicates the possibility of application of this nanohybrid for photovoltaic purpose.

  14. Tillage and planting density affect the performance of maize hybrids in Chitwan, Nepal

    Directory of Open Access Journals (Sweden)

    Tika Baladur Karki

    2015-12-01

    Full Text Available To find out whether the different tillage methods at different planting densities affect the performance of maize hybrids, an experiment was carried out at National Maize Research Program, Rampur during spring season of 2013 and 2014. The experiment was laid out in strip plot design with three replications having 12 treatments. The vertical factor was tillage with conservation tillage (No Tillage + residue=NT and conventional tillage (CT and the horizontal factor were genotypes (Rampur Hybrid-2 and RML-32/RML-17 and in split planting geometries (75cm × 25cm =53333 plants/ha, 70cm × 25cm=57142 plant/ha and 60cm ×25cm= 66666 plants/ha. In both the years, the highest number of cobs (73,177 and 67638/ha was recorded at planting density of 66666/ha. NT had the highest no of kernel rows/cob (14.01 as against 12.12 in CT in 2014. The highest number of kernels (27.3 and 29.29 per row was recorded in NT during 2013 and 2014 respectively. Similarly, in 2014, the highest number of kernels were found in RML-32/RMl-17 (29.17/row and planting density of 53333/ha (28.46/row. In 2013, RML-32/RML-17 produced the highest test weight of 363.94g over the Rampur hybrid-2 with 362.17g. Significantly the highest grain yield of 9240.00 kg/ha in 2013 and 7459.80 kg/ha in 2014 at planting geometry of 65cm ×25cm were recorded. No effects was found by tillage methods for grain yields of maize in 2013, but was found in 2014 (7012.18 kg in NT compared to 6037.59 kg/ha in CT. NT and wider spaced crop matured earlier in both the years; however Rampur hybrid-2 matured earlier to RML-32/RML-17 in 2013. In 2014, harvest index of 47.85 % was recorded in planting geometry of 66666/ha, the highest benefit cost ratio of 1.36 was worked out in NT and 1.46 at the density of 66666/ha. The highest value of 2.46% of soil organic matter was recorded in NT as compared to 2.43% in CT.

  15. Enhancement of hybrid rocket combustion performance using nano-sized energetic particles

    Science.gov (United States)

    Risha, Grant Alexander

    Until now, the regression rate of classical hybrid rocket engines have typically been an order of magnitude lower than solid propellant motors; thus, hybrids require a relatively large fuel surface area for a given thrust level. In addition to low linear regression rates, relatively low combustion efficiency (87 to 92%), low mass burning rates, varying oxidizer-to-fuel ratio during operation, and lack of scaling laws have been reported. These disadvantages can be ameliorated by introducing nano-sized energetic powder additives into the solid fuel. The addition of nano-sized energetic particles into the solid fuel enhances performance as measured by parameters such as: density specific impulse, mass and linear burning rates, and thrust. Thermophysical properties of the solid fuel such as density, heat of combustion, thermal diffusivity, and thermal conductivity are also enhanced. The types of nano-sized energetic particles used in this study include aluminum, boron, boron carbide, and some Viton-A coated particles. Since the combustion process of solid fuels in a hybrid rocket engine is governed by the mass flux of the oxidizer entering the combustion chamber, the rate-limiting process is the mixing and reacting of the pyrolysis products of the fuel grain with the incoming oxidizer. The overall goal of this research was to determine the relative propulsive and combustion behavior for a family of newly-developed HTPB-based solid-fuel formulations containing various nano-sized energetic particles. Seventeen formulations contained 13% additive by weight, one formulation (SF4) contained 6.5% additive by weight, and one formulation (SF19) contained 5.65% boron by weight. The two hybrid rocket engines which were used in this investigation were the Long Grain Center-Perforated (LGCP) rocket engine and the X-Ray Transparent Casing (XTC) rocket engine. The smaller scale LGCP rocket engine was used to evaluate all of the formulations because conducting experiments using the

  16. Simulation of storage performance on hydropneumatic driveline in dual hybrid hydraulic passenger car

    Directory of Open Access Journals (Sweden)

    Wasbari Faizil

    2017-01-01

    Full Text Available The charging process is one of the critical processes in the hydro-pneumatic driveline storage system. It converts the kinetic energy of the vehicle braking and coasting to the compression energy. This energy is stored in the storage device called the accumulator. The system is planned to be used on the dual hydro-pneumatic hybrid driveline and applied to a hydraulic hybrid passenger car. The aim of this paper is to find the effect of charging parameters on the storage performance through simulation. Through the storage behaviour, the desirable and optimal sizing of the accumulator can be selected. The paper emphasized on the effect of pressure elevation, pre-charge pressure, effective volume, thermal reaction and required time of the accumulator’s charging process. The circuit of charging process has been designed and simulated by using the hydraulic tool in the Automation Studio software. The simulation results were corroborated through the component specification for data rationality. Through the simulation, it was found that pre-charge pressure had a significant effect on the charging process. It determined the efficiency of the effective volume. The higher the pressure elevation, the higher the effective volume. Nevertheless, the more energy required to compress the nitrogen gas in the bladder. Besides, in term of volume displacement, higher volume displacement reduced charging time and lower the fluid temperature. The simulation had been positively highlighted the critical point in charging process which later on, benefited the sizing process in the component selection specification.

  17. Chemically bonded phosphorus/graphene hybrid as a high performance anode for sodium-ion batteries.

    Science.gov (United States)

    Song, Jiangxuan; Yu, Zhaoxin; Gordin, Mikhail L; Hu, Shi; Yi, Ran; Tang, Duihai; Walter, Timothy; Regula, Michael; Choi, Daiwon; Li, Xiaolin; Manivannan, Ayyakkannu; Wang, Donghai

    2014-11-12

    Room temperature sodium-ion batteries are of great interest for high-energy-density energy storage systems because of low-cost and natural abundance of sodium. Here, we report a novel phosphorus/graphene nanosheet hybrid as a high performance anode for sodium-ion batteries through facile ball milling of red phosphorus and graphene stacks. The graphene stacks are mechanically exfoliated to nanosheets that chemically bond with the surfaces of phosphorus particles. This chemical bonding can facilitate robust and intimate contact between phosphorus and graphene nanosheets, and the graphene at the particle surfaces can help maintain electrical contact and stabilize the solid electrolyte interphase upon the large volume change of phosphorus during cycling. As a result, the phosphorus/graphene nanosheet hybrid nanostructured anode delivers a high reversible capacity of 2077 mAh/g with excellent cycling stability (1700 mAh/g after 60 cycles) and high Coulombic efficiency (>98%). This simple synthesis approach and unique nanostructure can potentially be applied to other phosphorus-based alloy anode materials for sodium-ion batteries.

  18. High performance hybrid functional Petri net simulations of biological pathway models on CUDA.

    Science.gov (United States)

    Chalkidis, Georgios; Nagasaki, Masao; Miyano, Satoru

    2011-01-01

    Hybrid functional Petri nets are a wide-spread tool for representing and simulating biological models. Due to their potential of providing virtual drug testing environments, biological simulations have a growing impact on pharmaceutical research. Continuous research advancements in biology and medicine lead to exponentially increasing simulation times, thus raising the demand for performance accelerations by efficient and inexpensive parallel computation solutions. Recent developments in the field of general-purpose computation on graphics processing units (GPGPU) enabled the scientific community to port a variety of compute intensive algorithms onto the graphics processing unit (GPU). This work presents the first scheme for mapping biological hybrid functional Petri net models, which can handle both discrete and continuous entities, onto compute unified device architecture (CUDA) enabled GPUs. GPU accelerated simulations are observed to run up to 18 times faster than sequential implementations. Simulating the cell boundary formation by Delta-Notch signaling on a CUDA enabled GPU results in a speedup of approximately 7x for a model containing 1,600 cells.

  19. Efficient Electron Collection in Hybrid Polymer Solar Cells: In-Situ-Generated ZnO/Poly(3-hexylthiophene) Scaffolded by a TiO2 Nanorod Array.

    Science.gov (United States)

    Liao, Wen-Pin; Wu, Jih-Jen

    2013-06-06

    A nanoarchitectural hybrid polymer solar cell, integrating the ordered and the bulk heterojunction hybrid polymer solar cells, is fabricated by infiltrating the diethylzinc/poly(3-hexylthiophene) (P3HT) solution into the interstices of the TiO2 nanorod (NR) array. An inorganic network composed of tiny ZnO nanocrystals is constructed in the in-situ-generated hybrid within the interstice of the single-crystalline TiO2 NRs. The TiO2 NR array, which possesses a longer electron lifetime and an appropriate electron-transport rate, serves not only as an electron transporter/collector extended from fluorine-doped tin oxide (FTO) electrode to sustain the efficient electron collection but also as a scaffold to hold the sufficient amount of ZnO/P3HT hybrid. The in-situ-generated ZnO/P3HT hybrid layer with superior charge separation efficiency can therefore be thickened in the presence of a TiO2 NR array for increasing the light-harvesting efficiency. A notable efficiency of 2.46% is therefore attained in the TiO2 NR-ZnO/P3HT hybrid solar cell.

  20. Performance study of sugar-yeast-ethanol bio-hybrid fuel cells

    Science.gov (United States)

    Jahnke, Justin P.; Mackie, David M.; Benyamin, Marcus; Ganguli, Rahul; Sumner, James J.

    2015-05-01

    Renewable alternatives to fossil hydrocarbons for energy generation are of general interest for a variety of political, economic, environmental, and practical reasons. In particular, energy from biomass has many advantages, including safety, sustainability, and the ability to be scavenged from native ecosystems or from waste streams. Microbial fuel cells (MFCs) can take advantage of microorganism metabolism to efficiently use sugar and other biomolecules as fuel, but are limited by low power densities. In contrast, direct alcohol fuel cells (DAFCs) take advantage of proton exchange membranes (PEMs) to generate electricity from alcohols at much higher power densities. Here, we investigate a novel bio-hybrid fuel cell design prepared using commercial off-the-shelf DAFCs. In the bio-hybrid fuel cells, biomass such as sugar is fermented by yeast to ethanol, which can be used to fuel a DAFC. A separation membrane between the fermentation and the DAFC is used to purify the fermentate while avoiding any parasitic power losses. However, shifting the DAFCs from pure alcohol-water solutions to filtered fermented media introduces complications related to how the starting materials, fermentation byproducts, and DAFC waste products affect both the fermentation and the long-term DAFC performance. This study examines the impact of separation membrane pore size, fermentation/fuel cell byproducts, alcohol and salt concentrations, and load resistance on fuel cell performance. Under optimized conditions, the performance obtained is comparable to that of a similar DAFC run with a pure alcohol-water mixture. Additionally, the modified DAFC can provide useable amounts of power for weeks.